[From the U.S. Government Printing Office, www.gpo.gov]










                        Ground Water Supply Protection and Management Plan
                                       for the Eastern Shore of Virginiy,

                                                     May 5,1992



                                                      Prepared For:

                                               Eastern Shore of Virginia
                                           Ground Water Study Committee
                                               Accomac, Virginia 23301

         too


                                                       Prepared By:
                                            Horsley Witten Hegemann, Inc.
                                      Consultants in Water Resources and Land Planning
                                                    1680 E. Gude Drive
                                                 Rockville, Maryland 20850
                                                       (301) 294-9895





                              This document was prepared under a United States Environmental
                              Protection Agency 205(j) Water Quality Planning Grant for the
                              Virginia State Water Control Board, and was funded, in part, by the
                              Virginia Council on the Environment' s Coastal Resources Manage-
                              ment Program through grant #NA90AA-H-CZ796 of the National
                 TD           Oceanic and Atmospheric Administration under the Coastal Zone
                 224          Management Act of 1972 as amended.
                 N8
                 G76
                 1992


















               EASTERN SHORE OF VIRGINIA GROUND WATER STUDY COMMITTEE



                 GROUND WATER SUPPLY PROTECTION AND MANAGEMENT P
                          FOR THE EASTERN SHORE OF VIRGINI



                               RESOLUTION OF ADOPTION


              BE IT RESOLVED that the Ground Water Supply Protection
              and Management Plan for the Eastern Shore of Virginia is
              hereby adopted by the Eastern Shore of Virginia Ground
              Water Study Committee.





              Duly  adopted by the Eastern Shore of Virginia Ground
              Water Study Committee on May 5. 1992.

                   certification: X. A a,       I'-- (;V.
                                   C.D. Fleming @-f   Chairman
                                   Eastern Shore of Virginia
                                     Ground Water Study Committee


                                  State of Virginia
                                 County of Accomack

              The foregoing instrument was acknowledged before me on
              this 5th day of May, 1992, by C.D. Fleming, Jr., Chairman
              of the Eastern Shore of Virginia Ground Water Study
              Committee.


                                                Notary@6Pu

              my commission expires:











                                                      ACKNOWLEDGEMENTS







                   This report was prepared by Horsley Witten Hegemann, Inc. under contract with the Eastern Shore
                   of Virginia Ground Water Study Committee. In researching and developing this document, it was
                   necessary to collect information from many agencies and individuals. In particular, the following
                   individuals provided special assistance in the production of the document: Jack Green and Jim
                   McGowan, A-NPDC, Project Managers; Paul Berge, A-NPDC, Director; Virginia Newton, VA State
                   Water Control Board; Robert Jackson, VA State Water Control Board; Gary Speiran, U.S.
                   Geological Survey; Donna Richardson, U.S. Geological Survey; Rodney Lewis, Soil Conservation
                   Service. Many other local, state and federal officials contributed information or conducted reviews
                   of drafts, and their efforts are greatly appreciated. HWH also wishes to recognize our two
                   subcontractors Dr. Lewis Waters who conducted the land use analysis and Dr. Daniel Morrissey who
                   assisted in the hydrogeologic investigation.




































                       Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia








                                 Ground Water Supply Protection and Management Plan
                                                for the Eastern Shore of Virginia

                                                      TABLE OF CONTENTS


                                                                                                               PAGE:
                   1       INTRODUCTION


                           Overview                                                                            1-1
                           Executive Summary                                                                   1-3
                           Purpose of Project                                                                  1-6

                   2.      WATER RESOURCES ON THE EASTERN SHORE OF VIRGINIA


                           Topography and Soils                                                                2-1
                           Surface Water                                                                       2-2
                                    Hydrologic Units                                                           2-4
                                    Farm Ponds                                                                 2-6
                                    Tidal Wetlands                                                             2-6
                           Ground Water                                                                        2-6
                                    Introduction                                                               2-6
                                    Hydrogeology of the Eastern Shore Aquifers                                 2-10
                                    Summary of Existing Technical Reports                                      2-10
                                    Flow and Recharge Patterns on the Eastern Shore                            2-11
                           Water Use                                                                           2-14
                                    Crop Irrigation                                                            2-14
                                    Public and Industrial Water Use                                            2-18
                                    Private Water Use                                                          2-23
                                    Poultry                                                                    2-23

                   3.      CONTAMINATION THREATS


                           Waste water disposal                                                                3-2
                                    Public Sewage Systems                                                      3-2
                                    On-site Septic Systems                                                     3-2
                                    VPDES Permits and Mass Drainfields                                         3-4
                           Agriculture                                                                         3-4
                                    Fertilizers                                                                3-5
                                    Pesticides                                                                 3-10
                                    Animal Waste and Animal Carcasses                                          3-12
                           Industrial /Commercial Land Uses                                                    3-12
                                    Underground Storage Tanks                                                  3-12
                                    Toxic Chemicals                                                            3-13
                           Solid Waste Disposal                                                                3-15
                           Septage Disposal                                                                    3-18

                   4.      EXISTING LAND USE


                           Purpose                                                                             4-1
                           Overall Status of Land Use Controls                                                 4-1
                           Existing Patterns of Land Use                                                       4-2



                      Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia









                            Land Use and Open Space Requirements for Water                                   4-3
                               and Sewer
                            E)dsting Land Use in Accornack County                                            4-4
                                    Agriculture and Agricultural Districts                                   4-4
                                    Housing and Residential Districts                                        4-4
                                    Industry, Business, and Industrial/Commercial                            4-7
                                       Districts
                            Existing,Zoning and Land Use in Northampton County                               4-7
                                    Agriculture and Agricultural Districts                                   4-7
                                    Housing and Residential Districts                                        4-8
                                    Industry, Business, and Industrial/Commercial                            4-8
                                       Districts
                                    Other Uses                                                               4-9
                            Land Use Controls and Effects on Ground Water                                    4-10
                            Subdivision of Land                                                              4-12
                                    Subdivisions in Accomack County                                          4-13
                                    Subdivisions in Northampton County                                       4-14
                            The Chesapeake Bay Program on the Eastern Shore of Virginia                      4-14
                                    Introduction                                                             4-14
                                    Basic Approach                                                           4-14
                                    Implications for Ground Water Protection                                 4-15
                            Summary of Land Use on the Eastern Shore                                         4-17

                   5.       DELINEATION OF GROUND WATER SUPPLY MANAGEMENT AREAS


                            Introduction                                                                     5-1
                            Selection of Aquifer Protection Criteria                                         5-1
                                    Zone 1                                                                   5-1
                                    Zone 2                                                                   5-2
                                    Zone 3                                                                   5-3
                            Physical Description of Each Wellhead Protection Area                            5-6
                                    Wellhead Protection Area A - Chincoteague Area                           5-6
                                    Wellhead Protection Area B - Holly Farms (Tyson Foods) Area              5-6
                                    Wellhead Protection Area C - Perdue Area                                 5-7
                                    Wellhead Protection Area D - Exmore Area                                 5-7
                                    Wellhead Protection Area E - Cape Charles Area                           5-8

                   6.       WATER BUDGET/ BALANCE

                            Recharge to the Columbia Aquifer                                                 6-1
                            Recharge to the Yorktown-Eastover Aquifer                                        6-1
                            Salt Water Intrusion                                                             6-3


                   7.       BUILDOUT/DEVELOPABLE LOT ANALYSIS

                            Developable Lot/Land Use Analysis                                                7-1
                                    Methods                                                                  7-1
                                    Buildout Assumptions                                                     7-2
                            Buildout Analysis Results                                                        7-4
                            Buildout Analysis Summary                                                        7-4





                       Ground Water   Supply Protection and Management Plan for the Eastern Shore of Virginia










                   8.      NITROGEN LOADING

                           Introduction                                                                        8-1
                           Nitrogen as a Contan-dnant                                                          8-1
                           Sources of Nitrogen                                                                 8-3
                                    Sewage                                                                     8-3
                                    Fertilizers                                                                8-4
                                    Animal Waste                                                               8-4
                                    Lawn Fertilizers                                                           8-5
                                    Landfills                                                                  8-6
                                    Septage Lagoons                                                            8-6
                                    Pavement and Roof Runoff                                                   8-6
                                            Estimation of Paved Area/Roof Area                                 8-7
                                    Business/ Industrial/ Institutional                                        8-7
                                    Precipitation                                                              8-7
                           Nitrogen Loading Analysis                                                           8-7
                           Nitrogen Modelling Results                                                          8-8
                           Existing Water Quality Results                                                      8-11
                                    Virginia Department of Health, Public Water                                8-11
                                      System Inventory
                                    State Water Control Board/EPA STORET Database                              8-11
                                    Virginia Department of Health, Eastern Shore District                      8-13
                                    USGS Water Quality Sampling                                                8-13
                           Nitrogen Loading Analysis Under Future Buildout Conditions                          8-15

                   9.      CASE STUDIES AND THEIR APPLICABILITY TO THE
                                    EASTERN SHORE OF VIRGINIA

                           Agricultural Practices                                                              9-1
                                    Lancaster County, Pennsylvania: Fertilizer Effects on                      9-1
                                       Water Quality
                                    Jefferson County, Wisconsin: Controlling Disposal of                       9-3
                                       Livestock Wastes
                                    Delmarva Peninsula: Composting Dead Chickens                               9-4
                           On-site Waste Disposal                                                              9-6
                                    Ontario, Canada: Nitrogen Plumes from Septic Systems                       9-6
                                    Falmouth, Massachusetts: Performance Standards                             9-7
                                      Within Zones of Contribution
                                    Long Island, New York: Restrictions Within Recharge Zones                  9-8
                                    Gloucester, Massachusetts: Siting of Septic Systems                        9-19
                                    Locations Throughout The U.S. Constructed Wetlands,
                                       Alternative to Conventional Wastewater Treatment                        9-10
                           Surface Water Management                                                            9-11
                                    Chesapeake Bay Area, Maryland: Stormwater Pollutant                        9-11
                                      Reduction
                                    Buzzards Bay, Massachusetts: Stormwater Treatment System                   9-13
                                    Chesapeake Bay Area, Maryland: Vegetated Buffer Zones                      9-14
                                    Hazardous Materials Handling and Storage                                   9-15
                                    Portland, Oregon: Land Use Controls Within Wellhead                        9-15
                                      Protection Area
                                    Dayton, Ohio: Overlay District For Aquifer Recharge Area                   9-16




                      Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia








                                    Palm Beach County, Florida: Ground Water Protection                       9-17
                                      Through Zoning Ordinance
                                    Comprehensive Monitoring Programs                                         9-18
                                    State of Rhode Island: Salt-pond Watchers, Watershed Watch                9-18

                   10.     CONCLUSIONS OF THE REPORT


                   11.     RECOMMENDATIONS

                           Recommendations for Water Quality and Quantity Protection                          11-1
                           Recommendations for Water Quantity Management                                      11-3
                           General Recommendations                                                            11-5
                           Continued Research and Investigation                                               11-5



                   APPENDIX A - WATER QUALM                                                                   A-1

                   APPENDIX B - POPULATION                                                                    B-1

                   APPENDIX C - LAWS AND REGULATIONS APPLICABLE TO STUDY                                      C-1


                   APPENDIX D - EASTERN SHORE OF VIRGINIA GROUND WATER
                                      STUDY COMMITTEE                                                         D-1

                   APPENDIX E - HYDROGEOLOGIC CALCULATIONS                                                    E-1

                   APPENDIX F - BUILDOUT NITROGEN LOADING CALCULATIONS                                        F-1

                   APPENDIX G - REFERENCES AND RESOURCES                                                      G-1

























                      Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                    V










                                                              LIST OF TABLES



                                                                                                                     PACE:
                   Table 2-1       Towns and Villages Located by Hydrologic Units                                    2-4
                   Table 2-2       Agricultural Water Use by County                                                  2-16
                   Table 2-3       Irrigation Estimates, 1987-1989                                                   2-17
                   Table 2-4       Accomack-Northampton Planning District Irrigation With                            2-18
                                      Source Detail
                   Table 2-5       Summary of Permitted Public and Industrial Water Use                              2-18
                   Table 2-6       Major Municipal Withdrawals                                                       2-18
                   Table 2-7       Average Annual Water Withdrawals, Eastern Shore, Virginia                         2-19
                                      1985-1990
                   Table 2-8       Permitted Withdrawal Rates for Inactive Facilities                                2-22
                   Table 3-1       Public Sewage Facilities                                                          3-2
                   Table 3-2       Residential Disposal of Septic Wastes                                             3-3
                   Table 3-3       Facilities With Discharge Permits, Eastern Shore, Virginia                        3-6
                   Table 3-4       Facilities Using Mass Drainfields, Eastern Shore, Virginia                        3-8
                   Table 3-5       Nitrogen Fertilizer Requirements, Eastern Shore, Virginia                         3-11
                   Table 3-6       Underground Storage Tanks by Wellhead Protection Area                             3-14
                   Table 3-7       EPA List of Active Generators and Transfer Storage                                3-16
                                      Disposal Facilities, Accomack and Northampton Counties
                   Table 3-8       Virginia Toxic Substances Chemical Inventory, Accomack and                        3-16
                                      Northampton Counties
                   Table 4-1       Existing Land Use - Accomack and Northampton                                      4-3
                   Table 4-2       Land Use Category by Zoning District, Eastern Shore of Virginia                   4-5
                   Table 4-3       Zoning Lot Sizes and Open Space                                                   4-6
                   Table 4-4       Analysis of Land Use Effects on Ground Water Supplies                             4-10
                   Table 4-5       Subdivision Development in Accon-tack County, 1972-1990                           4-13
                   Table 4-6       Subdivision Development in Northampton County, 1974-1990                          4-14
                   Table 6-1       Salt Water Upconing Modelling Results                                             6-6
                   Table 7-1       Minimum Lot Sizes Used in Buildout Analysis                                       7-2
                   Table 7-2       Buildout Summary                                                                  7-4
                   Table 7-3       Calculations for Buildout Within Incorporated Towns,                              7-5
                                      Accomack County
                   Table 7-4       Calculations for Buildout Within Urban Development Areas,                         7-5
                                      Northampton County
                   Table 7-5       Developable Lot Analysis, Accomack and Northampton                                7-7
                                      Counties
                   Table 8-1       Total Nitrogen Concentrations in Septic System Effluent                           8-3
                   Table 8-2       Leaching Rates for Fertilizers Applied to Turf Areas                              8-5
                   Table 8-3       Total Nitrogen Concentrations in Road Runoff                                      8-6
                   Table 8-4       Nitrogen Loading Values                                                           8-8
                   Table 8-5       Nitrogen Loading Calculations: Accomack Existing                                  8-9
                   Table 8-6       Nitrogen Loading Calculations: Northampton Existing                               8-10
                   Table 8-7       Virginia Department of Health Public Water Test Results                           8-11
                   Table 8-8       Nitrate-nitrogen Levels Above 5 mg/I in STORET (EPA)                              8-12
                                      File, Accomack and Northampton Counties
                   Table 8-9       Eastern Shore Health District Shallow Well Monitoring Results                     8-13
                   Table 8-10      USGS Nitrogen Sampling,                                                           8-14
                   Table 8-11      Nitrogen Concentration By Wellhead Protection Area                                8-15
                   Table 8-12      Nitrogen Loading Under Future Buildout Conditions In Spine
                                      of Wellhead Protection Area per Source                                         8-16


                      Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                  v i








                    Table 9-1       Sampling Results in Two Pennsylvania Rivers                                    9-1
                    Table 9-2       Pollutant Reduction Goals by Land Use Categories, State of                     9-12
                                      Maryland
                    Table A-1       Regulated Contaminants                                                         A-1
                    Table B-1       1990 U.S. Census Population Counts, Accomack-Northampton                       B-1
                                    Planning District
                    Table B-2       Historical and Projected Population Figures                                    B-1
                    Table E-1       Water Balance for the Eastern Shore of Virginia                                E-1
                    Table E-2       Thornthwaite Method for Evapotranspiration (ET) Calculations                   E-2
                    Table E-3       Water Balance for the Eastern Shore of Virginia, Recharge to                   E-3
                                      Yorktown-Eastover (Confined) Aquifer
                    Table E-4       Recharge Calculations for the Yorktown-Eastover Aquifer                        E-4
                    Table F-1       WPA (A) Future Nitrogen Loading Calculation                                    F-1
                    Table F-2       WPA (A) Future Nitrogen Loading Calculation -Developable
                                      Soils Only                                                                   F-2
                    Table F-3       WPA (B) Future Nitrogen Loading Calculation                                    F-3
                    Table F-4       WPA (B) Future Nitrogen Loading Calculation -Developable
                                      Soils Only                                                                   F-4
                    Table F-5       WPA (C) Future Nitrogen Loading Calculation                                    F-5
                    Table F-6       WPA (D) Future Nitrogen Loading Calculation                                    F-6
                    Table F-7       WPA (E) Future Nitrogen Loading Calculation                                    F-7






























                       Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                  vi






                                                              LIST OF FIGURES                                PAGE:



                  Figure 1-1       Locus Map of Eastern Shore of Virginia                                    1-2
                  Figure 2-1       Soils Map                                                                 2-3
                  Figure 2-2       Map of Hydrologic Units                                                   2-5
                  Figure 2-3       Locations of Farm Ponds                                                   2-7
                  Figure 2-4       Hydrologic Cycle                                                          2-8
                  Figure 2-5       Generalized East/West Cross-section of Ground Water                       2-9
                                      Flow in the Eastern Shore of Virginia
                  Figure 2-6       Conceptual Hydrogeologic Model of Non-Pumping Ground                      2-12
                                      Water Conditions on the Eastern Shore of Virginia
                  Figure 2-7       Conceptual Hydrogeologic Model of the Eastern Shore With                  2-14
                                      a Pumping Well at the Edge of the Peninsula Screened
                                      in the Yorktown-Eastover Aquifer
                  Figure 2-8       Water Use by Category                                                     2-15
                  Figure 2-9       Yearly Precipitation Amounts, Painter, Virginia, 1985-1990                2-16
                  Figure 2-10      Industrial Water Withdrawals vs. Permitted Amounts                        2-24
                  Figure 2-11      Public Water Withdrawals vs. Permitted Amounts                            2-24
                  Figure 2-12      Public and Industrial Water Withdrawals vs. Pern-dtted                    2-25
                  Figure 2-13      Public and Industrial Water Withdrawals by Month, 1990                    2-25
                  Figure 3-1       Typical Sources of Contan-driation to Ground Water                        3-1
                  Figure 3-2       Septic System and Ground Water Contamination                              3-3
                  Figure 3-4       Underground Storage Tanks Broken Down By Age                              3-13
                  Figure 3-5       Locations of Landfill Sites and Septage Lagoons                           3-17
                  Figure 5-1       Eastern Shore Potentiometric Map: Permitted Pumping                       5-4
                  Figure 5-2       Map of Wellhead Protection Areas                                          5-5
                  Figure 6-1       Salt Water Intrusion                                                      6-4
                  Figure 6-2       Upward Vertical Migration of Salt Water                                   6-5
                  Figure 7-1       Example of Future Land Use Within Spine Recharge Area                     7-3
                  Figure 8-1       Nitrogen Transformations                                                  8-2
                  Figure 9-1       Scheme of Simple Poultry Composter                                        9-5




















                     Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                  vii




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                                                      INTRODUC-nON   I
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                   SEMON 1: INTRODUMON



                   OVERVIEW

                   Ground water resource protection and management on the Eastern Shore of Virginia (see Figure 1-1
                   for locus map) requires the involvement and cooperation of many levels of government as well as a
                   commitment from the private sector. The private sector plays an important role because ground
                   water withdrawals for operations such as industrial processing and agricultural irrigation greatly
                   exceed public water supply needs. If development progresses in the Counties of Accomack and
                   Northampton, however, the ratio of public to private water use is expected to rise.

                   The majority of ground water is withdrawn from deeper confined aquifers found on the Eastern
                   Shore. The water quality in these aquifers is generally very good. Ground water in the unconfined,
                   shallow aquifer is of poorer quality than that found in deeper aquifers, and is used primarily for
                   individual private wells and for irrigation. Septic systems, agriculture, and commercial and
                   industrial development have all been identified as potential sources contributing contan-driants to
                   the shallow aquifer, primarily in the form of nitrogen. The current low density of development
                   found on the Eastern Shore allows for the establishment of land use controls and cooperative efforts
                   to protect water quality by private and public institutions.

                   A major concern on the Eastern Shore is overpurnping of water from the deeper confined aquifers.
                   Although the volume of water stored in the aquifers and the recharge that infiltrates naturally
                   over the land surface has been calculated within a range of uncertainty of a factor of two to support
                   the current rates of water withdrawal, for the Eastern Shore as a whole, further salt water
                   intrusion may occur. In fact, Virginia State Water Control Board data from selected test wells
                   indicate decreases in water levels and increases in salinity adjacent to the largest industrial
                   withdrawal wells. Moreover, if the existing facilities increase their pumping rates to the
                   maximum volumes allowed in their permits, several areas of the Eastern Shore are predicted to
                   experience increasing problems of well interference, salt water intrusion, and a deterioration of
                   water quality.

                   Several management scenarios are available to ensure that there is adequate water in the future to
                   meet anticipated demands and to protect both the shallow and deep aquifer systems from a
                   deterioration in water quality.

                   This study summarizes available information on water withdrawals, land use threats, and current
                   control mechanisms on the Eastern Shore. Recommendations are proposed to develop a
                   comprehensive ground water protection and supply management plan which will maintain an
                   adequate supply of water and sustain high water quality for the future needs of the region.














                         Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia








                                        Figure 1-1: Locus Map of the Eastern Shore of Virginia





                                                       PENNSYLVANIA


                                          -- - - - -   - - - - - - - -f




                                            MARYLAND



















                                                                              DELAWARE





                                                                       L- - - - - -





                                                                       MARYLAND



















                                                                C3






                                                                                             30

                                                                               scaiW (miles)




                        Ground Water Supply Protection and Management     Plan for the Eastern Shore of Virginia
                                                                  1-2










                   EXECUTIVE SUMMARY


                   The Eastern Shore of Virginia is an 80 mile long peninsula that comprises about 696 square miles of
                   area, located at the southern tip of the Delmarva Peninsula and within the Eastern Coastal Plain
                   Province. The Eastern Shore is bounded on all sides by water, except to the north which is bordered
                   by the Maryland mainland. The Atlantic Ocean is to the east and the Chesapeake Bay to the west
                   and south.

                   Ground water is the only source of supply for domestic, industrial, and agricultural water use. A
                   total population of approximately 47,000 use this ground water. Most of the production wells are
                   set to draw water at various levels in the sen-d-confined aquifer (called the Yorktown-Eastover)
                   found at about 300 feet below mean sea level. The water table aquifer (called the Columbia) is used
                   extensively for agricultural irrigation and private wells.

                   Accomack and Northampton Counties are the administrative units that govern the Eastern Shore
                   and control all land use activities in conjunction with nineteen small towns. The Accomack-
                   Northampton Planning District Commission has commissioned the development of a Ground Water
                   Management and Supply Protection Plan that will provide a comprehensive and practical series of
                   options, alternatives and specific actions to promote compatibility between the Eastern Shore's
                   water resources and the counties land use plans.

                   In 1976 the Virginia State Water Control Board designated the Eastern Shore of Virginia a
                   "Ground Water Management Area". The Eastern Shore was the second area in Virginia to be
                   declared a ground water management area. This declaration was based on the findings that:

                           ï¿½ Ground water level declines have been observed in two sections of Accomack County;
                           ï¿½ Interference between wells has been observed in the same two sections of Accomack
                             County;
                           ï¿½ Some evidence of localized ground water contamination has been observed in the water
                             table aquifer of Accomack County but not in the confined aquifers;
                           ï¿½ Even though the ground water supplies in Accomack County are not overdrawn and are not
                             expected to be in the near future, it should be recognized that they may overdraw in some
                             areas in the future if water withdrawals are not distributed throughout the region.
                             Further, saltwater intrusion has not been observed to date but may occur in the future if
                             heavy ground water withdrawals are concentrated in any one area.

                   The major impact of the Ground Water Management Area designation is that all water users that
                   withdraw in excess of 10,000 gallons per day (gpd) are subject to a state permit process. Ten major
                   existing industrial and municipal withdrawals became grandfathered and did not have to subn-dt
                   extensive permit applications. Currently, there are no regulations controlling agricultural water
                   use, except for the reporting of water use on an annual basis.

                   The aquifers on the Eastern Shore are strongly influenced by the lithology. Annual precipitation of
                   42 inches per year provides the recharge to the aquifers. The upper aquifer, called the Columbia
                   Aquifer, is unconfined, and is roughly 80 to 100 feet thick. This aquifer is used primarily for private
                   on-site domestic wells, and agricultural irrigation. Approximately 2 million gallons per day are
                   withdrawn by private on-site wells for domestic use. Some portion of the 8.7 million gallons per
                   day withdrawn for irrigation comes from the Columbia aquifer.

                   Anywhere from 12 - 24 inches per year of precipitation recharges the Columbia aquifer on the
                   Eastern Shore of Virginia. At an average recharge rate of 17 inches per year, approximately 324
                   million gallons per day recharge the Columbia aquifer. Most of this water flows from the middle


                        Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                    1-3







                    of the peninsula and discharges to the Chesapeake Bay and the Atlantic Ocean. A small
                    percentage contributes to the recharge of the deeper confined aquifer.
                    Water quality in the Columbia aquifer is threatened by the many land uses that discharge, leach
                    or dispose of contaminants to the ground water. Nitrate-nitrogen is the primary contaminant of
                    concern to the Columbia aquifer. Sources include: septic systems; agricultural fertilizers; manure
                    storage and animal disposal; septage lagoons; and landfills. In addition, pesticides and
                    underground storage tanks are also threats. The average nitrogen concentration in the ground water
                    was calculated to be 2.0 milligrams per liter. The national drinking water standard for nitrogen is
                    10 milligrams per liter. On average, the shallow ground water quality is considered very good
                    however, those areas located down gradient from major nitrogen users or disposers will experience
                    much higher nitrogen concentrations.
                    The next water bearing zone is the Yorktown-Eastover Formation, a confined aquifer consisting of
                    coarse shelly sands found in three layers separated by clay confining units. This aquifer can range
                    in depth from 80 to 800 below the land surface, though most wells are pumping from layers between
                    150 and 300 feet deep. The clay confining layers that separate the Columbia aquifer from the
                    Yorktown-Eastover serve to protect the aquifer from many of the water quality threats. They also
                    act to impede the amount and rate of recharge to the aquifer. It is estimated that only 1.2 inches of
                    precipitation recharge the Yorktown-Eastover aquifer. Based upon the ground water modelling
                    studies conducted, approximately 11 million gallons per day is recharge to the Yorktown-Eastover.
                    However, it should be noted that this recharge value is based on average conditions across the
                    entire Eastern Shore, and depending upon specific site conditions can vary by a factor of two in
                    either direction. Additional study is necessary to better define the recharge rate to the Yorktown-
                    Eastover aquifer.
                    Industrial withdrawals and public water supply wells are exclusively screened in the Yorktown-
                    Eastover aquifer, while wells used for agriculture and private household use are withdraw from
                    the upper aquifer. Currently 4.5 million gallons per day are withdrawn from this aquifer for
                    industrial use and public water supply, Permits from the Virginia State Water Control Board
                    would allow withdrawals of up to 15.6 n-dllion gallon per day from this aquifer. If this were to
                    occur, problems of well interferences and salt water intrusion, already observed near the largest
                    industrial water users, will be greatly enhanced.
                    Local planning and elected officials on the Eastern Shore have been concerned for a number of years
                    about the quality and availability of ground water. The State Water Control Board of Virginia
                    has conducted several studies and developed a network of ground water monitoring wells on the
                    Eastern Shore to document problems. In addition, through cooperative studies, the U.S. Geological
                    Survey has developed reports and modelled the hydrogeology. The results of these investigations
                    all agree that the major issues are:

                            ï¿½ Agriculture, water quality and quantity;
                            ï¿½ Animal wastes;
                            ï¿½ Development impacts, septic systems, underground tanks;
                            ï¿½ Well interference, industrial and public water supply wells,
                            ï¿½ Salt water intrusion;
                            ï¿½ Adequate water supply, future demands, all uses.
                    Each of these activities/concems have an impact on water use and quality for either the upper
                    aquifer, the lower aquifer or both.




                          Ground Water Supply Protection and Manage?nent Plan for the Eastern Shore of Virginia
                                                                     1-4








                   A land use buildout study was conducted to assess the maximum potential for development within
                   the spine recharge area. The findings show that under current zoning, the number of single-family
                   dwelling units that could potentially be developed within the spine recharge area is greater than
                   the total number of existing units county-wide. This has serious implications for future wastewater
                   disposal,water supply and agricultural use. Buildout conditions were modelled for impacts on
                   ground water quality due to nitrogen contan-dnation. The area with the most likely impacts will be
                   in WPA (B) in the vicinity of Holly Farms (Tysons Foods).

                   The Ground Water Supply Protection and Management Plan For the Eastern Shore of Virginia
                   provides a review of each of these threats including land use impacts under future buildout
                   conditions. In addition, the recharge areas to the major pumping wells have been delineated. An
                   aquifer recharge zone was mapped based upon hydrogeologic information that suggests that the
                   source of recharge to the confined aquifer is located along the spine of the peninsula.
                   Based upon the analyses conducted and the review of existing information, the study proposes the
                   following actions:

                   Recommendations for Water Quality Protection

                   ï¿½ Pursue water conservation measures with major industrial users.
                   ï¿½ Create an overlay protection zoning district to protect the spine recharge area to the Yorktown-
                     Eastover aquifer;
                   ï¿½ Restrict the siting of new mass drainfields in the spine recharge area;
                     Review and revise county zoning and subdivision regulations;
                   ï¿½ Require the registration of currently unregulated underground storage tanks;
                   ï¿½ Incorporate ground water protection requirements into site plan review;
                   ï¿½ Develop a private well ordinance to control the siting and construction of new wells;
                   ï¿½ Support the implementation of agricultural nutrient management plans;
                   e Implement the provisions of the Chesapeake Bay Program.

                   Recommendations for Water Quantity Management

                   ï¿½ Revise State Ground Water Act and Regulations to allow for reevaluation of existing permits;
                   ï¿½ Develop an Eastern Shore Water Management District to manage water withdrawals;
                   9 Control the siting and development of new water supply wells to prevent well interference and
                     reduce the threat of salt water intrusion;
                   ï¿½ Continue the accurate reporting of agricultural water withdrawals, by well location and depth.
                     Continue the consideration of mandatory permitting of agricultural withdrawals after review of
                     reporting data.
                     Protect open space and undeveloped land in the spine recharge area.

                   General Recommendations

                   9 Implement a land use/water quality data base;
                   * Develop a public education program on ground water.

                   Continued Research and Investigation

                   0 Investigate the nature of recharge to the Yorktown-Eastover aquifer;
                   - Research dilute salt water issues;
                   - Conduct additional hydrogeologic studies to better define the geology;
                   e Evaluate pesticide use on the Eastern Shore;


                        Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                  1-5








                    ï¿½ Support additional agricultural nutrient management research;
                    ï¿½ Revise the nitrogen model used in the study over time.

                    The Eastern Shore of Virginia is situated over a very valuable ground water resource that is the
                    sole source of water supply to the inhabitants and is also necessary for both industrial and
                    agricultural use. Protection of the water quality and quantity will require the implementation of
                    many actions designed to maintain water quality, prevent against over use of the aquifer and
                    provide for the future needs to accommodate growth on the Eastern Shore.

                    PURPOSE OF PROJECr

                    This project prepared by Horsley Witten Hegemann, Inc. (HWH), was guided and funded by the
                    Eastern Shore of Virginia Ground Water Study Committee. The committee was formed for the
                    purpose of assisting local governments and residents of the Eastern Shore to understand, protect and
                    manage their ground water resources. In addition to serving as an informational and educational
                    resource, the Committee initiates special studies concerning the protection and management of the
                    Eastern Shore. This Ground Water Resources Protection and Management Plan is one of several
                    ways in which the Committee intends to carry out its goals.

                    The Committee consists of 2 members from each county's Board of Supervisors, one citizen appointee
                    by each Board of Supervisors, the County Adn-dnistrator from each county, and the Executive
                    Director of the Accomack-Northampton Planning District Commission.

                    This report responds to three aspects of the Committee's purpose:
                    1. The report provides management information by identifying the quantity of ground water
                        available for use, and explaining the potential for de-watering of the ground water aquifers,
                        salt water intrusion, and contamination.

                    2. The report provides recommendations regarding ground water quality protection; identification
                        and protection of ground water recharge areas; nitrate-nitrogen loading to the water table;
                        land application of pesticides; and hazardous material storage.
                    3. The report, combined with public forums, maps, and background information on the
                        hydrogeologic cycle and ground water conditions on the Eastern Shore, advises the public as to
                        their role in protecting ground water and identification of threats to water quality and
                        quantity.
                    An additional goal of this project is to improve coordination among those municipalities, state and
                    local governments, and private sectors responsible for the protection, management, and research
                    regarding the Eastern Shore ground water supply.












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 I
 I
 I
 I
 I
                        WATER RESOURCES ON THE EASTERN SHORE OF VIRGINIA
 1                                                                     2
 1
 1
 1
 1
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 I
 I
 I
 I
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                   SECTION 2: WATER RESOURCES ON THE EASTERN SHORE


                   Ground water is the only source of drinking water on the Eastern Shore, and is therefore considered
                   the most important water resource. However, an understanding of the water system as a whole is
                   necessary to understand future land use and development decisions designed to protect water
                   supplies. This section provides an overview of the water resources on the Eastern Shore of Virginia.
                   Soil types and the geology which influence water quality and quantity are also discussed.

                   TOPOGRAPHY AND SOILS

                   Accomack and Northampton Counties lie in the Coastal Plain Province of Virginia. The soils of the
                   two counties are predominantly comprised of sand, clay, and shell fragments, deposited during the
                   Miocene Era Tennema and Newton, 1982). The resulting land is one of the most productive in the
                   entire Atlantic Coastal Plain.

                   The region is generally flat, with a central plateau. Maximum elevation of the plateau is 45 feet
                   above mean sea level, and the slope rarely exceeds two percent. From the central northeast-
                   southwest trending divide, the land gradually slopes toward the Chesapeake Bay and Atlantic
                   Ocean shorelines.

                   Soil characteristics greatly influence the activities which may take place on the land above them,
                   and thus play a significant role in planning and development. For example, layout and grading of
                   roadways, excavations for foundations of new buildings, and the operation of septic tanks are all
                   affected by soil suitability. Factors such as permeability, depth, natural fertility, and drainage
                   are important when considering agricultural potential and future development sites. Soil drainage
                   is particularly important on the Eastern Shore where the primary method of disposing domestic
                   waste water is by septic systems. If the soil is not suited for wastewater disposal, waste water must
                   be transported to an area of suitable soil, or else be treated in a central treatment facility.
                   According to the Soil Survey of Northampton County (Soil Conservation Service,1989 and 1990) and
                   the Accomack County Comprehensive Plan (1989), there are five major soil associations on the
                   Eastern Shore of Virginia. A soil association is an area of land made up of two or more
                   geographically associated soils which occur in a similar pattern. The following paragraphs
                   summarize the Soil Conservation Service's characteristics of these soil associations:

                   Bojac-Munden-Molena
                   This association makes up 48% of the two counties. It is nearly level to steep, moderately well
                   drained to somewhat excessively drained, loamy and sandy soils; on broad flats, side slopes, and
                   escarpments. Of the five associations, this one is the best for development. However, there are
                   some development limitations due to erosion, wetness, and shallowness of sorts. Munden soil, in
                   particular, is considered excellent for development. Septic tank suitability is moderate, generally
                   limited by poor drainage.

                   Ninimo-Munden-Dragston
                   Covering 15% of the two counties, this association is nearly level, moderately well drained to
                   poorly drained, consisting of loamy soils found on broad flats and depressions. The association is not
                   always suitable for development. Septic tank suitability is severe due to a seasonal high water
                   table and poor drainage.





                         Ground Water Supply Protection and Manage?nent Plan for the Eastern Shore of Virginia
                                                                    2-1









                   Chincoteague-Magotha
                   Covering 28% of the two counties, this association is nearly level, very poorly drained to poorly
                   drained, silty and loamy soils, found in tidal marshes. Not suitable for development, the soils are
                   best utilized as wetland wildlife habitat and as spawning grounds for shellfish and finfish. This
                   association is frequently flooded, has a moderate natural fertility, and is well suited for salt-
                   tolerant plants.

                   Nimmo-Arapahoe
                   Located in the northwest portion of Accomack County only, this association covers 5% of the two
                   counties. It is level, poorly drained, and suitable for development and agriculture if properly
                   drained. The Soil Conservation Service on the Eastern Shore, however, considers the area where
                   these soils lie to be undevelopable.

                   Fisherman-Beaches-Camocca
                   Covering 4% of the two counties, this association is nearly level to steep, moderately well drained
                   and poorly drained, sandy soils and beaches, found on flats and low dunes and depressions. Because
                   of the location in wetland resource areas, the soil association is not suitable for development.

                   Figure 2-1 displays the locations of these soils.

                   The soil types located on the mainland of the peninsula (except Nimmo-Arapahoe) are categorized
                   as prime farmland. This category constitutes 68% of the land in the counties of Northampton and
                   Accomack. Water bearing capacity of these soils is moderate, and the natural fertility is low.
                   Typically these soils are acidic. They are well suited to cultivated crops, soybeans, small grains,
                   vegetables, and ornamentals (SCS, 1989).

                   In general, the two counties contain soils that are less than ideal for proper septic system
                   functioning, generally due to a seasonal high water table. The Accomack County Comprehensive
                   Plan maintains that the Bojac-Munden-Molena soil associations are well drained and suitable for
                   development and agricultural lands. These soil types constitute 44% of Northampton County's
                   land, and 52% of Accomack County, and thus are the most prevalent soils. It should be noted that
                   the entire town of Chincoteague, Accomack County's most developed magisterial district, is
                   underlain by the Fisherman-Beaches-Camocca formation, which is described as unsuitable for
                   development because of poor drainage and susceptibility to a seasonal high water table, flooding,
                   and instability (SCS, 1989). Chincoteague receives its water from several wells on the mainland
                   near the NASA Wallops facility, and so does not need to be as concerned about ground water
                   contan-tination problems within the town. However, any residents using private wells should be
                   wary of the quality of their water, given the number of septic systems in this poorly suited soil.

                   SURFACE WATER

                   Surface water includes ponds, streams, creeks, bays, and lagoons. The Eastern Shore is unique
                   compared to mainland Virginia in that there are no major streams or other surface water supplies
                   which can serve as a source of drinking water. This point underscores the importance of protecting
                   the ground water supply, because alternative sources for drinking water do not exist. Surface water
                   systems are, however, interconnected with ground water. The water table on the Eastern Shore of
                   Virginia is shallow, and surface water and ground water play an important interactive role.

                   Although not used for drinking water, surface water systems are important for shellfish, finfish,
                   and other wildlife.on the Eastern Shore. These animals benefit the general economy of the area:
                   the finfish industry grossed over one million dollars in 1986, and the sale of shellfish in 1986 was



                         Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                     2-2



























                                                                                                                  OCEAN
                                                     ATLANTIC


                                                                                                                                                  AL












                                               .. . .......








                                                                                CHESAPEAKE




                    FISHERMAN-BEACHES-CAMOCCA

                    CHINCOTEAGUE-MAGOTHA

                    BOJAC-MUNDEN-MOLENA

                    NIMMO-MUNDEN-DRAGSTON

                    NIMMO-ARAPAHOE





              I LOW   0          22.000 33.000
                       scale (1001)



                                                                                                       2-3









                  valued at over nine million dollars, according to the Accomack County Comprehensive Plan (1989).
                  The Virginia State Water Control Board and the Virginia Department of Health Shellfish
                  Sanitation monitor the overall quality of surface water to protect public health in recreational
                  contact and to insure that the waters can sustain aquatic life.

                  As a result of flat topography and well-drained soils, the peninsula has no large fresh water lakes
                  or waterways. Instead, there are several creeks which, in the lower reaches, are tidal estuaries
                  fed by narrow branches. The Chesapeake Bay side of the peninsula receives the majority of surface
                  runoff, where the creeks are more pronounced. On the Atlantic Ocean side, the barrier islands
                  create a bay and lagoon system, and this side has smaller creeks. In Accomack County, 12 creeks
                  feed into the ocean side, and 19 creeks ebb and flow into the Bay. In Northampton County, there are
                  21 watersheds, with 15 on the Bay side.

                  Currently, a water quality monitoring project of tidal creeks in Northampton County is underway.
                  It is a collaborative effort between the Citizens for a Better Eastern Shore (CBES), The University
                  of Virginia, the Virginia Coast Reserve of the Nature Conservancy, the Eastern Shore Working
                  Waterman's Association, and the Virginia Student Environmental Health Project (STEHP). The
                  project will provide baseline information on the status of aquatic habitats and surface water
                  resources of Northampton County. All data derived in the project will eventually be accessible to
                  the general public, and a report completed by the end of 1991 will be submitted to the local board of
                  supervisors and the planning district commission. Recommended actions are expected to result from
                  the presentation of the report.

                  Hydrologic Units

                  The USDA Soil Conservation Service has grouped together the 52 watersheds on the Eastern Shore
                  Peninsula to form fourteen (14) hydrologic units. These are essentially larger management units
                  which have common drainage areas. Figure 2-2 indicates the boundaries of the hydrologic units.
                  The following is a breakdown according to county and village. The units beginning with the letter
                  "C" are on the west (Bay) side of the peninsula, and the "D" units are on the east (Ocean) side.
                  Lower numbers are farther south than higher numbers.

                                      Table 2-1: Towns and Villages Located by Hydrologic Units

                        Accomack Coun!y:
                        C04: [Belle Haven, Bloxom, Craddockville, Davis Wharf, Middlesex, half of Painter, and
                             half of Pungoteaguel
                        C05: [Harborton, half of Melfa, and half of Pungoteaguel
                        C06: [Onancock and half of Onleyl
                        C07: [Greenbush, Hallwood, Horsey, Leemont, Mappsville, Mears, Nelsonia, Parksley,
                             Sanford, Saxis, Tasley, and half of Withams]
                        C08: [New Church, Oak Hall, and half of Withams]
                        D03: [Keller, half of Painter, Quinby, and half of Wachapreaguel
                        D04: [Accomac, Centerville, Locustville, half of Melfa, half of Onley, and half of
                             Wachapreaguel
                        D05: [Temperanceville and half of Wallops Island]
                        D06: [Atlantic, Chincoteague, Greenbackville, Horntown, Half of Wallops Island, Wallops
                              Station, and Wattsvillel

                        Northa=ton Coun1y:
                        C01: [Dalbys]
                        C02: [Cape Charles, Cheriton, and Chesapeake]


                        Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                  2-4












                                                         C08                                    town

                                                                            Rue                                     D06
                                                                                          .in

                                              F" I                                                          ISLAND
                                                Poco"00CE                                                  NATIONAL
                                                                                             chi""      ;I SIASHOIK
                                       C07 soumose"Asy
                                                          Bay
                                                    mamom 'r                                 D05.
                                          w"ge I                            an   Od       n


                                             Mesconos                     pas
                                   C06      P"

                                  Cos                            ley                 D 0 4
                                                            Mel



                                                                       pr
                                  crad   Voila
                                                        sinter

                                                         ,In
                             C04          lie
                                            adl                            Patramom I
                                          svillo           h
                                            le

                                            0                         Quit D 0 3
                                                    Hoe Island
                            J"                r         3&y
                     C03          hipon

                                     J.
                                                                  044 machiponso
                                                                      Inift
              cl- C 0 2         kin                          c-" D02
                                                Cobb
                                                 34      UtLw cow WNW
                 CAP* C              S91-
                                                ouch
                                                say
                   C01-p i                                DO 1
                                                                                             FIGURE 2-2
                                    T
                                   CIOM
                                                                                           MAP OF
                         cam                                                        HYDROLOGIC
                                     FfSKERMAMS ISLAND
                                    'N w R                                                   UNITS


                                                                                             110 -wVv-LrM-ll
                                                                                             E


                                                                    2-5








                        C03: (Bridgetown, Churchneck, half of Eastville, and Machipongol
                        C04: [Bayford, Birdsnest, half of Exmore, Jamesville, half of Nassawadox, and Silver
                            Beach]
                        DOI: [Capeville, Seaview, and Townsend)
                        D02: [Half of the Town of Eastville]
                        D03: [Half of Exmore, half of Nassawadox, Weirwood, and Willis Wharf]

                  Faim Ponds

                  In the two counties, over 325 excavated "farm ponds" supply about 85% of the water used for
                  irrigation (Cooperative Extension Agents Jim Belote, Fred Diem, personal communication, 1991). It
                  is unknown how many of these ponds are used as storage areas for water that has been pumped from
                  wells. Farm pond locations, as supplied by the Accomack-Northampton Planning District
                  Comn-dssion, are shown in Figure 2-3. Some of the locations in Figure 2-3 have multiple ponds.
                  While it is unclear which of these ponds intersect the water table, the use of surface water for
                  irrigation, rather than well water, reduces the stress on the use of the deeper ground water supply
                  However, farm pond construction by creek damming may destroy valuable wetland habitat and
                  negatively effect downstream productivity (Paul Gapcynski, William & Mary, Virginia Institute
                  of Marine Science [VIMSL Eastern Shore Natural Resources Symposium speech 4/11/91). Two
                  studies conducted by VIMS have shown no negative effects on downstream productivity (letter from
                  J. Rodney Lewis, SCS, 7/8/91).

                  Ditches have also been constructed on the Eastern Shore to connect creeks in order to increase
                  drainage (Fennema and Newton, 1982). This has the effect of increasing surface water runoff rates.
                  Additionally, several dams have been built in estuaries below and at the head of tide water to
                  supply irrigation water.

                  Tidal Wetlands

                  Both Accomack and Northampton Counties contain numerous tidal wetlands. Wetlands are some of
                  the most ecologically productive systems in the world, and are sensitive to land development and
                  use. Tidal wetlands serve as water filters, mitigate the impact of storms, and provide habitat for a
                  variety of wildlife, aquatic life, and plants. Accomack County has 70,000 acres of vegetated tidal
                  wetlands, divided between salt marshes along the Atlantic Ocean shoreline, and brackish marshes
                  on the Chesapeake Bay shoreline. Accomack County also contains extensive non-vegetated
                  intertidal flats on the ocean side. Non-vegetated tidal wetlands are located between mean high
                  water and mean low water and are adjacent to tidal marshes. Tidal wetlands in Northampton
                  County are located on both the ocean and bay sides, and total 35,000 acres.


                  GROUND WATER


                  Introduction

                  The Eastern Shore of Virginia depends entirely upon ground water supplies for its municipal and
                  industrial water needs. Virtually no streams or rivers exist on the peninsula, nor are there surface
                  water lakes or reservoirs of appreciable size.

                  Ground water serves the water supply needs of the Eastern Shore today, and will continue to do so in
                  the foreseeable future. As a result of this dependence on ground water, protection of the resource,
                  both in terms of water quantity and water quality, takes on an added importance.



                        Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                 2-6













                                                              ATLANTIC                                                           OCEAN

                                                                                                                                                   C3

                                                             oo 4fo%o                    00
                                                                                    00          0                   0
                                                                             %                            09 1
                                             0                                                                                                          000 0
                                                                                                                                               *,to 0 0 9 o oo
                                                                 0    0                        0             0                                        000
                                                                                                     A%..       0*                                            0      %
                                                                                                0               00                                         0
                                                                      9                             4i-              00 0

                                                                                                                                                 @c




                                                                                             CHESAPEAKE



                9      APPROXIMATE LOCATION OF                                                                                                                                                       FIGURE 2-3
                       FARM PONDS
                                                                                                                                                                                             LOCATIONS OF
                                                                                                                                                                                               FARM PONDS








                 11.000  0           22.000 33.ODO
                                             -1
                          scale (loot)                                                                                                                                                                       1HI

                                                                                                                        2-7








                  Ground water on the Eastern Shore is derived from precipitation falling on the land surface of the
                  two counties. Some of that water is intercepted by vegetation and is transpired or evaporated
                  directly back to the atmosphere. A portion runs off as overland flow while some penetrates the soil
                  and is used (transpired) by plants. Part of the precipitation moves through the unsaturated zone
                  and recharges the unconfined (Columbia) aquifer. Figure 2-4 below illustrates the hydrologic
                  cycle. Most water in the Columbia aquifer flows laterally from the center of the peninsula,
                  contributing to the baseflow of small streams or is held in temporary storage in ponds before
                  discharging to the Atlantic Ocean or Chesapeake Bay. A much smaller portion of water in the
                  unconfined aquifer continues its vertical inigration through the clays and silts that separate the
                  Columbia from the underlying Yorktown-Eastover aquifer, recharging the confined aquifer system.
                  See Figure 2-5.
                  Tangier Island, a small island that is part of Accomack County and is located ten miles off the coast
                  of Virginia in the Chesapeake Bay, also obtains drinking water from ground water sources. The
                  island has a separate hydrogeologic system from the mainland, and was not studied in detail in
                  this report.                        Figure 2-L- Hydrologic Cycle



                                            A? rr

                                                                   ORMUM MW
                                                                        -RV-APCRAT-ION MANSPIPATWN

                                                                                                 NPLTMTM










                                           DOW. - OF
                                          @Nc WATUt
                                              %9W












                        Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                    2-8









                                                                                                                                                                       Figure 2-5 Generalized EastfWest Cross Section





                                                                                                                                               GENERALIZED EAST / WEST CROSS-SECTION
                                                                                                                                              OF GROUND WATER FLOW ON THE EASTERN
                                                                                                                                                                                                         SHORE OF VIRGINIA





                                                                                                                               WEST                                                                                      ICentral Plateau I                                                                                                                             EAST
                                                                                                                      Chesapeake                                                                                  PRECIPITATION                                                                                                                                           Atlantic
                                                                                                                                     Bay                   +                    +                   +                    +                     +                     +                  +                    +                      +                  +                   ocean
                                                                                                                                                                                           see                                                                                                              Water Table
                                                                                                                                                                                                                                                                                                                                           Piezometric Level




                                                                                                                                                                                                                                                               . . .............. ..            .......         ... ......
                                                                                                                                                                                                                                                               ..... .. ............
                                                                                                                                                                                                                                                               ....... .
                                                                                                                                                                                                                                                                                 ...                                            ...... ...
                                                                                                                                                                                                                                                               . . . . . . . . . . .




                                                                                                                                                                                                                                                                                 . ..... . . . . . . . . . .

                                                                                                                                                                                                           . . . . . . . ...... . . . . . . . . . . . . .
                                                                                                                                                                                                                           ........... .....
                                                                                                                                                                                                                       . ........










                                                                                                                                                           it
                                                                                                                                                       a                                                                                                                                                                                                   Salt
                                                                                                                                                                                                                                                                                                                                                       3round
                                                                                                                                           Ground
                                                                                                                                             Water
                                                                                                                                                                                                                                                                                                                                                       Water


                                                                                                                           ED Fresh water Aquifer
                                                                                                                           7 Fresh Water Aquitard
                                                                                                                                                                                                                                                                                                                                           Piezo"



































                                                                                                        Ground Water Supply Protection and Management Plan for the EaVern Shore of Virginia
                                                                                                                                                                                                                                                      2-9








                   Hydrogeology of the Eastern Shore Aquifers

                   The most important geologic formations with regard to ground water supply are the Columbia and
                   the Yorktown-Eastover. The Columbia was deposited during the Pleistocene (10,000 to 15,000 years
                   before present). The sediments are primarily sands with interfingering clay and silt beds. From a
                   water budget calculation, it was determined that between 12 and 26 inches per year recharges the
                   unconfined system (see Appendix R Much of that recharge flows laterally through the Columbia
                   aquifer and discharges to the Chesapeake Bay, streams and estuaries as well as the ocean. Some
                   water passes through the 20- to 100-foot thick confining unit of silty clay below the Columbia and
                   enters the other aquifer of importance to the Eastern Shore, the Yorktown-Eastover Formation.

                   The Yorktown-Eastover was deposited during the Miocene era, between 5 and 23 million years
                   before present. This deposit consists of three layers of aquifer separated by confining units.
                   Recharge to the confined system from the unconfined Columbia aquifer at steady state, pre-pumping
                   conditions is estimated from analytical modelling at approximately 0.10 feet per year (See
                   Appendix E). The Upper, Middle, and Lower aquifers are comprised primarily of fine to coarse
                   shelly sands. Thickness of the permeable sections vary from as little as 10 feet to as thick as 120
                   feet. The aquifer deposits possess moderate permeability with transn-dssivities ranging from less
                   than 1,000 gpd/ft (130 ft2/day) to as high as 40,000 gpd/ft (5300 ft2/day) (F&ME, 1990; Fennema
                   and Newton, 1982). Transn-dssivity is the measurement of how much water moves through the
                   aquifer, and is measured by multiplying the permeability of the aquifer by its thickness. The three
                   aquifers are separated by confining units composed of clays and silts of much lower permeability.
                   These units range from less than 10 feet to as much as 70 feet in thickness.

                   In addition to the Columbia and Yorktown-Eastover aquifers three major paleochannels (coarse
                   sediments deposited in stream channels that cut through the older sedimentary deposits) have been
                   identified on the Eastern Shore (Colman and others, 1990), created by the downcutting of streams
                   during several periods of low sea level during the Pleistocene. Two of these channels cross the main
                   body of the Eastern Shore peninsula, at Exmore and at Eastville. The third major channel crosses
                   south of the peninsula near Cape Charles and Fisherman's Island. The streams that formed the
                   channels cut into the Yorktown-Eastover Formation as much as 200 feet, depositing sands and
                   gravels in the central portion of the channel overlying those sediments with less permeable sands,
                   silts and clays (Colman and others, 1990). The width of the paleochannels is less certain but is
                   mapped in Colman and others (1990) as roughly 1-2.5 miles wide.

                   Summary of Existing Technical Reports

                   Available technical reports, including journal articles, consultant's reports, State Water Control
                   Board and U.S. Geologic Survey publications were reviewed for this project to better understand the
                   previous investigations of the Eastern Shore.

                   The technical literature can be divided into three principal categories. The first include those
                   reports presenting basic geologic and hydrologic data. Such reports are fundamentally
                   compilations of data with descriptive commentary and include many of the U.S. Geological Survey
                   papers and Virginia Division of Mineral Resources reports. For example, Teifke (1973) provides a
                   thorough exan-dnation of the geology of the entire coastal plain of Virginia, including the Eastern
                   Shore. The publication is a very useful one with its detailed rock type descriptions from borehole
                   logging as well as its discussion of depositional environments for the formations that make up the
                   region. Sinnott and Tibbitts (1968) offer a comprehensive overview of the geology and hydrology of
                   the Eastern Shore in particular, along with well and water quality data.




                        Ground Water Supply Protection and Manage?nent Plan for the Eastern Shore of Virginia
                                                                  2-10








                    The second type of report comes from independent researchers and consultants. These reports (e.g.,
                    F&ME, 1990) focus on local aspects of Eastern Shore hydrogeology. Their main utility in terms of
                    the objectives of a ground water protection program lies in the raw data they provide from drilling
                    logs and water quality analyses along with data from test pumping that can be used to obtain
                    aquifer coefficients.
                    The third type of report is more interpretive in form, applying the basic data to the issues
                    involving the hydrogeology of the Eastern Shore. Many of the Virginia State Water Control Board
                    Planning Bulletins fall into this category. A series of Planning Bulletins, No. 45 (1975), No. 309
                    (1977) and No. 332 (1982), have charted the efforts of the Board to detail the hydrogeologic
                    conditions of the Eastern Shore in both a conceptual and quantitative manner, along with
                    discussions of how that understanding can contribute to solutions to ground water problems. Bulletin
                    No. 45 offers a comprehensive view of hydrogeologic conditions on the Eastern Shore as they
                    existed almost twenty years ago. That report identified the following key issues: (1) ground water
                    level declines in the confined Yorktown-Eastover aquifer, (2) well interference, (3) salt water
                    intrusion, and (4) ground water contamination that continue to trouble the area. Bulletin No. 309
                    (Ball, 1977) acted on a specific recommendation of Bulletin No. 45 to construct a two-dimensional
                    numerical flow model of the confined aquifer of the Eastern Shore to apply a more quantitative
                    approach to the understanding and management of the resource. That trend towards a quantified
                    view of the hydrogeology was continued in Bulletin No. 332 (Fennema and Newton, 1982) which
                    augmented Bulletin No. 45's basic information, incorporating borehole geophysical data, water
                    quality information from established research stations and test pumping results. That report
                    presented a series of extremely useful cross-sectional correlations along and transverse to the axis of
                    the peninsula. A forthcoming report from the U.S. Geological Survey (Richardson, in press)
                    continues the move towards quantification of the hydrogeologic conditions of the Eastern Shore
                    with a three-dimensional saltwater/freshwater interface numerical model of the area.

                    Flow and Recharge Patterns on the Eastem Shore
                    A conceptual understanding of the flow patterns and locations of the recharge areas on the
                    peninsula is crucial to protecting those areas of most importance to the water supply of Accomack
                    and Northampton counties. That conceptual model must take a three-dimensional approach which
                    incorporates vertical components of flow to account adequately for the hydrogeologic conditions on
                    the Eastern Shore. The key element of that model with respect to protecting the long term quality
                    and quantity of the ground water on the Eastern Shore is the role played by the central spine of the
                    peninsula. The center portion functions as the primary recharge source for the heavily used
                    confined Yorktown-Eastover aquifer, and the center portion's protection is of utmost importance to
                    the continued viability of the confined aquifer as a source of water.
                    The overall flow and recharge patterns can perhaps best be illustrated through the use of several
                    models developed during the course of this project. The models are cross-sectional views of the
                    peninsula used to observe where ground water is recharged and discharged by the various aquifer
                    systems and the nature of flow within and between aquifers and confining units. The models used
                    were generated numerically by McDonald-Morrissey Associates in conjunction with HWH. United
                    States Geological Survey MODFLOW code was used to model input parameters of aquifer and
                    confining unit thickness, permeability, recharge rates, etc., consistent with those found in the
                    literature for the Eastern Shore. Several steady state model runs were performed to gain a better
                    conceptual view of the ground water flowpaths and recharge areas under different pumping
                    scenarios. While numerical in form, the runs of the model serve best as aids in developing a correct
                    conceptual notion of ground water conditions on the Eastern Shore. Figure 2-6 describes the flow
                    system of ground water under pre-pumping conditions on the peninsula. This figure is for conceptual
                    purposes only and does not represent a quantitative estimate of the recharge area.


                         Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                     2-11









                         FIGURE 2-6.
                         Conceptual Hydrogeologic Model of Non-Pumping Ground Water Conditions
                         on the Eastern Shore of Virginia



                        Chesapeake                  Columbia                                 Confining                                              Upper Yorktown-Eastover                                       Upper Yorktown-Eastover                            Atlantic
                        Bay                        Aquifer                                    Unit                                                  Aquifer                                                       Confining Unit                                      Ocean




                                                                                                                                                XK
                                                                                                                                                -K



                                                                                                                                                  . . . . . . . . . . .



                            tall

                          Water
                                                                                                                                                                                                                                                                    Water
                                                                                                                                                                        ..........
                                                                                                                   .........................
                                               . .......... ...........                                            . . . ...................


                                                                                                                   ..........
                                                          ...........
                                                                                             ...............                                                                                                                       ..... ...
                                                                                    .. ...........................          .........
                                                                                                        .............
                                                                                                                                                                                           -...........              ......... . . ....
                                                                                                                                                                                           ........                                   .................. .
                                                                                                                                                                                              .. ......                      ...
                                                                                             ............................... .. .........                                  ... :..    :.. .. 1.*1 , *:: ...
                                                                                  .. ... ...                                                                                    . .....
                                                                                                                                                                                                                                          .... .......
                                                                            . . .........
                                                           . I . . . . . . . . . . . . . . ......... .................
                                                                        .........                                                                                                              . ...................... .... .. ---------------
                                                                                                                                                                                                  ..............................

                                                                                                                                                                                                  .............

                                                                   . ...............................................
                                                               .......          .. . ........... ........
                                                                     ....... ........






                                                               FAddle Yorktown-Eastover                                              Midde Yorktown-Eastover                                            Lower Yorktown-Eastover
                                                               Aquifer                                                               Confining Unit                                                     Aquifer
                                          F] Recharge Pathway Flow to Columbia Aquifer
                                          F__] Recharge Pathway Flow to Upper Yorktown-Eastover Aquifer
                                          Lo Recharge Pathway Flow to Middle Yorktown-Eastover Aquifer
                                          MM Recharge Pathway Flow to Lower Yorktown-Eastover Aquifer

                                                                                                                                                         2-12








                    Precipitation falling on or across the peninsula recharges the unconfined Columbia aquifer. Much of
                    that water moves laterally within the unconfined unit and discharges to the ocean or Chesapeake
                    Bay. A portion continues vertically downward through the confining unit until it reaches the
                    Yorktown-Eastover aquifer. The model shows that the deepest portion of the Yorktown-Eastover
                    aquifer (the lower Yorktown-Eastover) receives its recharge from a very narrow strip along the
                    central spine of the peninsula. Once in the lower Yorktown-Eastover aquifer, water moves
                    laterally and then upward through the confining layers, finally to discharge into the Atlantic
                    Ocean or Chesapeake Bay. The Middle and Upper Yorktown-Eastover aquifers receive their
                    recharge in a similar manner, but from a broader area on either side of the peninsula, reflecting
                    both the higher permeabilities of those units as well as their relative stratigraphic positions.
                    That is, there are fewer confining units to go through before the water reaches the aquifers.
                    The model demonstrates the fact that recharge to the confined Yorktown-Eastover aquifer under
                    pre-pumping conditions occurs at the center of the peninsula. Precipitation falling on the sides of
                    the peninsula moves laterally through the Columbia aquifer, not vertically downward through the
                    confining layer. Much of the water recharged to the Columbia, therefore, discharges to the
                    Atlantic Ocean and the Chesapeake Bay, not the Yorktown-Eastover aquifer.
                    Figure 2-7 conceptually illustrates a scenario of steady state pumping conditions, detailing the
                    pathlines of ground water movement to a pumping well located at the edge of the peninsula. In a
                    somewhat non-intuitive manner, this cross-sectional numerical model shows that the surface area
                    of land immediately around the well contributes nothing to its yield. Precipitation falling on the
                    Eastern Shore in the immediate vicinity of the well will recharge the Columbia aquifer, but the
                    majority of flow in those areas does not pass through the confining layer to recharge the Yorktown-
                    Eastover aquifer and contribute to the yield of the well. In this cross-sectional model, recharge
                    from precipitation to the Columbia aquifer around the wellhead will discharge to the ocean. The
                    recharge source of a water supply on the side of the peninsula is primarily derived from the central
                    area of the land, albeit skewed towards the direction of the well to some degree. In this model, the
                    deepest section of the Lower Yorktown-Eastover aquifer actually obtains its water from beyond the
                    mddpoint of the peninsula in this pumping scenario.
                    As the distance between a pumping well and the center of the peninsula spine increases, a well will
                    derive its water supply from more than one area. Part of its recharge will continue to come from the
                    center of the peninsula, but part will come from other areas of the Columbia, induced by the
                    gradients created by pumping. A detailed quantification of precisely where these areas n-dght be
                    was not possible under the scope of this project. With a properly constructed and calibrated three
                    dimensional model, particle tracking routines could be used on the final head distribution to
                    determine to a much higher degree of precision the origin of the water discharged by a well. This
                    would offer a superior quantification of the proportion of water derived from downward leakage
                    through the confining layer near the well relative to water derived from recharge at the center of
                    the peninsula. Unfortunately, such a three-dimensional flow model does not yet exist for the
                    Eastern Shore, and its construction is beyond the scope of this project. The numerical cross-sectional
                    model was created for conceptualizing purposes, and it serves only to emphasize the importance of
                    the center of the peninsula to the quantity and quality of water available to the confined aquifer
                    system. While other areas of the Columbia undoubtedly contribute to the water supply of wells
                    screened in the Yorktown-Eastover aquifer, even for wells located at the sides of the Eastern Shore,
                    the key recharge area is the center of the land mass.
                    The numerical modelling which generated the conceptual hydrogeologic model for the Eastern
                    Shore illustrates a concept vital to the development of wellhead and aquifer protection strategies
                    on the Eastern Shore. Simply stated, the most important area to protect in order to assure continued
                    good quality and large quantities of ground water throughout the Eastern Shore is the center of the


                         Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                     2-13







                       Figure 2-7
                       Conceptual Hydrogeologic Model of the Eastern Shore of Virginia with a Pumping Well
                       at the Edge of the Peninsula Screened in the Yorktown-Eastover Aquifer


                                          Pumping Well
                                          at Edge of                                                                                                                                                                                                          Atlantic
                    ChesaPake             Peninsula                                                        Recharge Area                                    Center of                                                                                           Ocean
                    Bay                            Q                                                       for Well                                         Peninsula




                                                                                                                                                                                                                                Columbia Aquifer
                                                                                                                              . ............ ...............



                                                                                                                                                                                                                                  Confining Unit

                                                                                                                                                                                                                                                                    tit
                        wale    r                                                                                                                                                                      Upper Yorktown-Eastover Aquifer                          water.

                                                                                                                            . ...........                                                    Upper Yorktown-Eastover Confining Unit                  i
                                                                                                      .......... .             .............
                                                                                                  .. .. ....... . ...........         ....
                                                                                                        ....................
                                                                                                                                 ..........

                                                                                                                         ................
                                                      ..... . .......     ........
                                                  ............. ... .. ........                                 ...................
                                                            ..............                            ....... ...... .
                                                   ............
                                                    ...............*..............                           ....       ......
                                                            . .......... ..
                                                                                                                                                                                                                          -Eastover Aquifer
                                                            .............. X.               ............... %%% .........                                                                           Middle Yorktown
                                                .............%. ............... .... ..... . . ....................................
                                                ...............
                                                            ............ ......    . ............................. .......
                                                                   . .............. ....................I. ......
                                                                                                 ............
                                                                                                                                                                                          Middle Yox t
                                                                             .................................                                                                                              wn-Eastover Confining Uni             i
                                                                   ................. ..... ... .... ....... ...
                                                .............         - ---------- -------------------



                                                            ............
                                                                                                                                                                                                 Lower Yorktown-Eastover Aquifer
                      L

                                     F-I        Recharge Pathway Flow to Upper Yorktown-Eastover Aquifer
                                                Recharge Pathway Flow to Middle Yorktown-Eastover Aquifer
                                                Recharge Pathway Flow to Lower Yorktown-Eastover Aquifer


                                                                                                                                            2-14








       peninsula. Under pumping conditions, the important role of the central portion of the peninsula in
       maintaining adequate aquifer protection is even more apparent. A protection scheme that does not
       emphasize the center portion of the Eastern Shore, taking into consideration the three-dimensional
       character of the flow paths, will prove rrdsleading and ineffective.


       WATER USE

       A water budget for the Eastern Shore of Virginia has been established by comparing known water
       withdrawals to the rate of recharge to the aquifer. This budget will help identify water quality
       and salt water intrusion problems as well as predict the overall future of the ground water supply of
       the Eastern Shore of Virginia.
       This section identifies major water users, which include public, industrial, private, crop irrigation,
       and poultry categories. In Section 6, the water budget is analyzed with respect to the
       hydrogeologic conditions of the peninsula.
              20   Figure 2-8: Water Use by Category
              18 -
              16    ...               Agriculture
              14--        .....
                        .. ...... ....-
                        ..... . .......
                                      Industrial
              12--./                  Private
              10-               --------------- Public

               8-

               6

               4-

               2

               0
               1986 1987 1988 1989 1990 1991


                        Years



       Crop Irrigation
       Agriculture is the most water-intensive land use on the Eastern Shore. The State Water Control
       Board estimates the gallons of water used for irrigation based upon a voluntary survey which is
       completed by farmers. As of 1991, this survey will no longer be voluntary, and it is expected that
       the estimations will become more comprehensive if not more accurate. The following (Table 2-2) is
       a summary of agricultural water use (in millions of gallons per day - MGD) according to the
       Virginia State Water Control Board. Table 2-3 provides greater detail of this chart.







          Ground Water Supply Protection and Manage?nent Plan for the Eastern Shore of Virginia
                          2-15









                                                  Table 2-2: Agriculture Water Use by County (MGD)

                                                           12az               im                 im              IM

                              Accomack                     6.04               6.46               6.86            2.56
                             NQW=MOM                       5.17               3D8                1.94            2.62


                      Crop irrigation involves a seasonal use of water, but the figures have been annualized to give an
                      average daily withdrawal over the course of each year. Total irrigation did decrease from 1987 to
                      1989, and this coincides with an increase in rainfall, as shown in Figure 2-9.


                                                             Figure 2-9: Yearly Precipitation
                                                                Fainter, Virginia, 1985-1990


                                         60.0-
                                         575-
                                         55.0-                                                                   Precipitation
                                         52.5-                                                                   Average
                                         -%.0-
                                                                                         N,
                                         47.5-

                                         45.0-
                                  %      42.5-        0
                                                      M
                                               ------------
                                         40.0-                                 Y
                                         37.5-                       -Boor

                                         32.5--
                                         30.0 1       1        1   ' I
                                            1984    1985     1986    1987    1988    1989    1990    1991


                                                                         Years
                      Source: National Oceanic and Atmospheric Administration

                      Earlier in this section, it was estimated that surface water farm ponds supply approximately 85%
                      of the irrigating water. The State Water Control Board includes source information in its survey.
                      Table 2-4 summarizes the findings. According to the state survey, ground water contributes much
                      more than the 15% that is estimated by the Extension Service, and a small amount of public water
                      is also used.















                            Ground Water Supply Protection and Management Plan for the Eastern Shore                     of Virginia

                                                                              2-16












                  V                                                              Table 2-3: Irrigation Estimates, 1987-1990

                                                                                  Reported          % of            Reported          % of water
                           Year Geographic Numbers                Reporting       Acreage         acreage             Water            applied Annualized Ave. appl. Rainfall (in.)
                                       Area            Farms       Nurseries      Irrigated         in VA        Applied (MG)            in VA        Rate (mgd)             (in.)      AEr.-Sept.
                 1Z        -
                           1987      Accomack             72            12           9588             21.9              2204                22-2           6.037             8.5             12.61
                                   Northampton            30            3            7122             162               1888                19.1           5.173             9.8
                                      Virginia            520           47           43866            100               9916                100            27.168            8.3

                  ;3       1988      Accomack             118           18           10397            26                2357                25.7           6.457             8.3             22.43
                                   Northampton            42            8            5760             14.4              1125                12.3           3.083             7.2
                                      Virginia            430           75           39945            100               9181                100            25.152            83
                                                                                                                        1324                               3.628


                           1989      Accomack             43            11           10182            413               2502                48             6.855               9             30.27
                                   Northampton            41            4            5563             22.5                707               13.6           1.938             4.7
                                      Virginia            278           46           24669            100               5211                100            14.278            7.8

                           1990      Accomack             31                         4210                                 935                                2.56            8.18            27.21
                                   Northampton,           24                         4829                                 956                                2.62            7.29
                   M
                   Ln      Source: Virginia State Water Control Board - VA Crop Irrigation Water Use Reports for 1987-1989,1990 figures unpublished from the SWCB.
                           Rainfall data from NOAA, not SWCB.



                  ft








                              Table 2-4: Accomack-Northampton Planning District Irrigation With Source Detail

                                                         1987                            1988                         1989
                                                Acres          Millions         Acres        Millions       Acres         Millions
                          Water Source          Irrigated      Gaons            Irrigated    Gallons        Irrigated     Gallons

                          Surface Water         4,666          1,552            5,361        1,072          6,420         1,136
                          Ground Water          8,802          2,198            9,318        2,334          8,141         1,956
                          Mixed Source          2,510          172              1,479        77             1,082         116
                          Public Supply         664            171              0            0              104           1
                          TOW                   16,621         092              16,157       3A82           15,747        3,210
                     Source: Virginia State Water Control Board

                     Public and Industrial Water Use


                     Nonagricultural facilities which withdraw in excess of 300,000 gallons of ground water per month
                     are required to obtain a withdrawal pern-dt from the Virginia State Water Control Board (SWCB).
                     The effect of the pern-dt is to put a limit on the amount each facility can withdraw. The pern-titted
                     amount allotted to each system may include a grandfathered amount plus an amount based upon
                     historical use. Generally these wells are dug into the deep aquifer. The following is a sun-unary of
                     withdrawals in millions of gallons per day. Table 2-7 lists facilities which have permits and
                     their withdrawals from 1985 to 1990. Some listed in the database as currently withdrawing water
                     do not have a permitted rate of withdrawal, according to the SWCB. Those facilities without a
                     pern-dt have a "+" symbol in the "Permitted" column of Table 2-7 .


                                   Table 2-5: Summary of Permitted Public and Industrial Water Use (MGD)

                                                im       12H      JM       JM        JM      JM         Permitted (1991)

                          Public                1.3      1.3      1.4      1.4       1.5     1.2                 4.5


                          Industrial            3.4      3.1      3.2      3.1       3.4     3.3                11.1


                          Total                 4.7      4.4      4.6      4.5       4.9     4.5                15.6


                     Six incorporated towns have central water supplies. Together they withdrew approximately 1.03
                     millions of gallons a day in 1990. Table 2-6 lists the withdrawal amounts for each municipal
                     supply.

                                                      Table 2-6:  Major Municipal Withdrawals

                                           Town                   1990 Withdrawal                     Permitted Amount
                                                                  (MGD)                               (MGD)

                                           Cape Charles           0.134                               0.261
                                           Chincoteague           0.447                               1.340
                                           Eastville              0.060 (1989)                        +
                                           Exmore                 0.166                               0.320
                                           Onancock               0.161                               0.234
                                           Parksley               0.060                               0.100


                          Ground Water     Supply Protection and Manage?nent Plan for the Eastern Shore of Virginia
                                                                           2-18












                                                                              Table 2-7: Average Annual Water Withdrawals, Eastern Shore, VA 1985-1990

                    C)                Well No. ITOWN/FACILITY                                          LATITUDE LONGITUDE                      1985        1986        1987         1988      1989       1990 PERMITTED*
                                      PUBLIC SUPPLIES
                                      Accornack      County
                                      100-OOD41      Accomack Co. Nursing Home                             374528             7,53721          0.0160      0.0150      0.0145       0.0145    0.0166     0.0181         0.0294
                                      100-00039      Captain's Cove #1                                     380010             752534           0.0190      0.0180      0.0189       0.0117    0.0112     0.0081           +
                                      100-00031      Captain's Cove #2                                     375949             752500                                                0.0062    0.0043     0.0044
                                                     Captain's Cove #5 (out of service)                    375911             757528
                                      100-00265      Chincoteague #3                                       375626             752725           0.0270      0.0400      0.0751       0.0827    0.0280       0
                                                     Chincoteague #3A          same meter as #5            375626             752725                                                          0.0084
                                                     Chincoteague #3B                                      375626             752725                                                          0.0084     0.0552
                     110                             Chl@coteague #3C                                      375626             752725                                                          0.0084     0.04%
                                      100-00028      Chincoteague 04                                       375633             752721           0.1850      0.1840      0.1795       0.1572    0.1711     0.1392          134
                                      100-00032      Chincoteague 15                                       375626             752723           0.0390      0.0410      0.0314       0.0126    0.0056     0.004
                                      100-00320      Chincoteague #6                                       375641             752714           0.1590      0.1340      0.1752       0.1729    0.1713     0.1349
                                      100-00493      Chincoteague GA                                       375550             7527.54          0.0660      0.0790      0.0510       0.0354    0.0549     0.0351
                                      100-00494      Chincoteague #7B                                      375557             752749                                                0.0354    0.0435     0.0286
                                      100-00495      Chincoteague VC (closed - high iron)                  375604             752742                                                0.0000
                                                     NAs7k-Waflops Island #3                               375144             753034                                                          0.0138     0.0057
                                      100-00568      NASA-Wallops Island                                   375035             752545                                                          0.0099     0.0209
                                                     NASA-WaUops Island Well #4                            375128             753045                                                          0.0048     0.0098
                                      100-00002      Onancock                                              374233             754430                                                0.0782    O.OB71     0.0971          0.2388
                                      100-00004      Onancock                                              374233             754432           0.0990      0.0960      0.1186       0.0052    0.0044
                                      100-00036      Onancock                                              374234             754430                                                0.0469    0.0435     0.0486
                                      100-00037      Onancock                                              374259             754453                                                O.OU75    0.0049     0.0054
                                      100-00038      Onancock                                              374259             754454                                                0.0076    0.0098     0.0101
                                      100-Ml         Parksley #I                all wells, same            374703             753901                                   0.0816       0.0728    0.0738     0.0575           0.1
                                      100-00013      Parksley #2                meter                      374703             753902
                                      100-00014      Parksley #3 (not in service since 1984)               374704             753859
                                      100-00439      VA-Landing Campground                                 372844             754742                       0.0090      0.0133       0.0111    0.0088     O.OU79            +
                                      100-00207      Wallops Island Main Base                              375626             752807           0.1720      02050       0.11%        0.1420    0.1994     0.1009           0.263
                                                     Wallops Island Station                                375135             753034           0.0710      0.0150      0.0247       0.0220    0.0099                      0.127

                      tn              Northamp n County
                      ;a-
                      04              165-00042      America House Motor I meter for 2 wells               370816             755808           0.0140      0.0110      0.0116       0.0089    0.0076                     0.0209
                                      165-00260      America House Motor Inn # 1                           370815             755810                                                0.0063    0.0076     0.0032
                                      165-OW28       Cape Charles (Does not exist??)                       371605             760017                                 1              0.0000                  0             0.261
                                      165-00048      Cape Charles 01                                       371605             760022           0.1570      0.2050    1 0.1852       0.1100    0.0766     0.0105
                                      165-00123      Cape Charles #2                                       371607             760011                                                0.0509    0.15M      0.1231
                                                     Cherrystone I loliday Trav-L-Park                     371719             760043           0.0600                                                                      0.06
                                      1165-00030     Eastvffle #3                                          372117             755640                                                0.0000    0.0000               U06
                                      1165-00031     Eastvifle                                             372116             755640           0.0450      0.0490      0.0447       0.0000    0.0000
                                      [iC5-70-0036   EastvWe                                               372117      1      755640                                                0.0000    O.aw



      MMMOMMM                                                                                                                                                                             ==Now==












                                                                        Table 2-7: Average Annual Water Withdrawals, Eastern                 Shore, VA 1985-1990

                  C)             Well No. TOWN/FACILITY                                       LATITUDE LONGITUDE                   1985        1986        1987       1988      1989   1 1990      PERMITTED*
                                 165-00038     Eastville (backup)                                 372106           755620                                             0.0000    0.0000
                  ;3             165-00014     Exrnore #2                                         373230           754917          0.0670      0.1030      0.0675     0.0570    0.0509    0.1111          0.32
                                 165-00015     Exrno- #1                                          373230           754917          0.0410      0.0630      0.0773     0.0673    0.0667    0.055
                                 165-00026     Eastville #2 (#5)                                  372117           7556,40                                            0.0591    0.0580                      +
                                 165-00001     Northampton-Accomack Hospital                      372835           755145          0.0190      0.0120      0.0000     0.0748    02749     0.1039           0.1
                                 165-00025     Northampton-Accomack Hospital                      372835           755145          0.0490      0.058U      0.0782     0.0003    0.0024    0.0015
                  3Z                           Brown &    Root                                    371500           760000                                                                                  1.1
                  :9                           ViCanio    Residential Communities                 371314           760009                                                                                 028
                  1z             165-00259     ViCanio    Chesapeake .                            371333           760006                                                                                 0.022
                                 165-00054     Peaceful   Beach, Kirkwood #1                      373114           75-566D                                                                                0,229
                                 165-00055     Peaceful   Beach Campground      02                373114           755660
                                 rl-65-00063   Peaceful   Beach Campground      #3                373114           75-%60
                                               Peaceful   Beach, Kirkwood                         3731W            755630          0.0000   1  0.0000   1  0.0000_1   0.0000 1  0.0000 1

                                 Public Supply Total                                                                               1.2430      1.2640      1.2594     1.2414    1.4148    1.1140         4.4617

                                 INDUSTRIAL SUPPLIES
                  ;2             Accornack     County
             t-i  M,
             t!'  O-Q            IOD-00006     Byrd Foods #1                                      374537           754004          0.0370      0.0060      0.0031     0.0027    0.0071    0.0101           0.6
             C)                  100-00054     Byrd Packing Co.                                   374531           754011
                                 100-00367     Byrd Foods #3                                      374534           754007
                                 100-00368     Byrd Packing Co.                                   374536           754003
                                 IOD-00369     Byrd Packing CO.                                   374536           754003
                                 IOD-00009     Holly Famis #4                                     375318           753344                                  02045      0.22%     0.1901    0.2512           1.8
                                 100-OMIO      Holly Farnis #3                                    375311           753339                                  0.1996     0.1972    0.1692    0.1179
                                 100-00011     Holly Farnis #2                                    375304           753332                                  0.2412     0.1785    0.1863    0.1598
                                 IOD-00012     Holly Farnis #1                                    375256           753324          0.6870      0.7170      0.1619     0.1009    0.0924    0.1061
                  M              IOD-001%      Holly Farnis 05                                    375330           753355                                  0.0838     0.1153    0.1953    0.1581
                  M                             -
                  tn             100-00566     Holly Farnis #6                                    375257           753321                                             0.0175    0.0364    0.026
                  !1             100-00258     New Church Energy Assoc.                           375833           753218          0.0970      0.1570      0.0759     0.1435    0.1991    0.1767          0.336
                  ;3             100-00365     New Church Energy Assoc.                           375838           753218                      0.0300      0.1099     0.0361    011775
                                 100-0(X)20    Perdue Foods #4A                                   374403           753937          0.1060      O.WM        0.0221     0.01%     0.0618    0.224          2-6379
                                 100-00026     Perdue Foods #2                                    374419           753910          0.4640      0.4710      0.4468     0.4001    0-9M      0.4974
                                 100-00029     Perdue Foods #3                                    374429           753922          0.4450      0.4100      0.4336     0.4328    0-3956    0.41T6
                                 100-00030     Perdue Productions 11                              374408           753859          0.2510      0-2140      0.2038     0.1929    0.2280    0.244
                                 IOD-00195     Perdue Foods #4                                    374421           753937          0.2310      0.1970      0.1622     0.0928    0.1429    0.1157
                                 100-00531     Perdue, Inc. #5                                    374425           753933                                  0-3217     0-3273    03763     0.3683
                                 100-00843     Eastern Shore Seafood (pumpstart2/91)              375122           753336                   1           1                                                  0-3
                                 1100-00237    Shore Seafood # 1                                  375513           754348          0.3230      0.1990        0000     UR        0.0734    0.0941            +
                                 IIOD-00238   IShore Seafood 92                                   375512           754348                                             0.0000    0.0243    0.0941
                                               Shore Seafood #3                                   375512           754348                                                       0.0734    0.0941












                                                                        Table 2-7: Average Annual Water Withdrawals, Eastern Shore, VA 1985-1990

                     C)            Well No. TOWN/FACILITY                                     LATITUDE LONGITUDE                   1985       1986       1987       1988      1989 1 1990 PERMITTED*
                                                                                                                                                                              0.1005    0.094
                                                Shore Seafood #4                                  375512           754348                                                                      1
                                   100-00229    Taylor Packing Co.                                375232           753528          0.2070     0.1030     0.0680     0.0630    0.0440                   0.5488
                                   -100-00346   Taylor Packing Co. # 1                            375233           753528
                                   100-00347    Taylor Packing Co. #2                             375233           753528
                                   IOD-M8       Taylor Packing Co. #3                             375233           753528

                                   Northamp n County
                                   165-00108    American Original Foo same meter         123      373045           754828          0.1190     0.1140                0.0000    0.1155  1 0.0617          0.45
                                   165-00116    American Original Foods Obs. #123                 373046           754825                                           0.0000
                                   165-00117    American Orig. Foods Obs. #122                    373046           754925                                           0.1562
                                   165-00110    Bayshore Concrete # 1                             371544           760119          0.(Tl%     0.0820     0.0727     0.0382    0.0209    0.0166         0.125
                                   165-00111    Bayshore Concrete #3                              371542           760124                                           0.0069    0.0141    0.0151
                                   165-00142    Bayshore Concrete Prod. #2                        371539           760114                                           0.0251    0.0197    0.0178
                                   -165-00141   Bayshore Concrete                                 371539           760114                                           0.0054    0.0019    0.004
                                   165-00045    C&D Seafood #2                                    371711           755524          0.0610     0.0460     0.0380     0.0286    0.0260    0.0297         0.152
                                   165-00064    C&D Seafood #1
                                   165-00018    Cus     Enterprises                               372150           755572                                                                              0.441
                     ;1            165-00019    Custis Enterprises                                372150           755522
                                   165-00005    Exmore Foods #7                                   373203           754917                                                                              2.002
                                   165-00029    ExmoTe Foods #8                                   373160           754917
                                   165-00039    Exmore Foods #9                                   373210           754913
                                   165-00047    KMC Foods (clustered wells)                       371746           755728                                                               0.0033           1.6
                                   165-00023    KMC Foods #4             (Labor Camp)             371746           755728          0.2390     0.1860     0.2748     0.2156    0.0161
                                   165-00024    KMC Foods #5                                      371731           755730                                         1
                                   165-00105    KMC Foods Plant Well                              371732           755736
                                   1165-00158   KMC Foods Inc.                                    371726           755729
                     :31                                                                                                                                                                0.0341 1         0.15
                                                Sea Watch International (HAS)                     372219           755530       1  0.0660     0.0430     0.0335 JJW383      1 0.0389

                                   Industrial Total                                                                                3.4120     3.0520     3.1573     3.0641    3.4331    3.4296       11.1427

                                   GRAND TOTAL                                                                                     4.6550     4.3160     4.4167 4.3055        4.8479    4.5436       15.6044
                     tn
                     a,
                     Q             Source: VA Water Control Board Records 1985-1990; Virginia Newton, SWCB geologist                          Permitted    Grandfathered rights + Permitted withdrawals



                     03.
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                   Tangier Island supplies water for its population of 659 by means of 5 private water systems. These
                   wells are not used for industrial purposes, only by residential and commercial facilities. According
                   to the Eastern Shore Water Supply Plan (1988), the five wells were interconnected in 1987, and a
                   storage tank was built in the case of emergency. Many pipes to the wells are old and leak, and it is
                   difficult to determine flow from these wells since they are not metered. It was estimated in 1988
                   that the water demand for the town was .065 MGD. It is unknown how many wells exist on the
                   island; the State says 11 and a well driller claims there are 14 wells Since Tangier Island is
                   separate from the aquifer system on the mainland, and the water is withdrawn from a much greater
                   depth (approximately 1,000 feet deep),this study did not focus in detail on the ground water
                   situation on the island.

                   Five permitted water withdrawal facilities are currently inactive. Their permitted amounts total
                   just over 4 million gallons per day. Table 2-8 lists those inactive facilities and their permitted
                   withdrawal rates.


                                     Table 2-8: Permitted Withdrawal Rates for Inactive Facilities

                                        Facility                    Permitted Amount NGD)

                                        Exrnore Foods                       2.002
                                        Custis Enterprises                  0.441
                                        Peaceful Beach, Kirkwood            0.229
                                        DiCanio                             0.302
                                        Brown & Root                        1.100
                                           TOTAL                            4.074

                   In addition, there are numerous schools, hotels, restaurants, small industries, trailer parks,
                   churches, and n-dgrant labor camps that have private wells. Populations of community, non-
                   community, and non-transient non-community facilities were obtained from the Virginia
                   Department of Health. Water use by category was estimated using wastewater flow rates from
                   Laak (1986), assuming that eighty percent of water use becomes wastewater (see page 8-3).
                   Calculations show that these facilities use 140,000 gallons per day.
                   From the Eastern Shore Department of Health, it was determined that a maximum of 3,058 people
                   can occupy the area's migrant labor camps. Because these camps become the worker's residence
                   during the duration of the season, average water use per person is estimated at 55 gallons per person
                   per day. Therefore, the estimation of total labor camp water use is 168,000 gallons per day.
                   Conservatively, if the labor camps were all in operation at the same time, the total water
                   consumption from all these private facilities (schools, churches, etc.) amounts to 308,000 gallons per
                   day, or 0.308 MGD. Cumulatively, these facilities withdraw close to the permitted pumping rate
                   for the Town of Exmore.

                   Industrial withdrawals exceed that of the public facilities. The two poultry industries, Perdue Inc.
                   and Holly Farms (Tyson Foods) account for forty-two percent (42%) of the total permitted amount
                   for industry. The following graphs compare withdrawals to permitted amounts. Figure 2-13 shows
                   the seasonal fluctuations in water use during 1990.

                   Private Water Use

                   With only seven towns having public water systems, the majority of residents on the Eastern Shore
                   of Virginia obtain their drinking water from private domestic wells. Some of these wells are
                   shallow and withdraw water only several feet below the water table. The Virginia Water Project


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                   Inc. (1988) estimates that on the Eastern Shore, the number of year-round housing units with
                   individual drilled wells, individual dug wells, or some other private water source is 14,035. At a
                   per household use of 165 gallons per day, private water use exceeds 2.3 million gallons per day.
                   Another method of estimating private water use involves subtracting the number of people served
                   by public water systems as listed by the SWCB (13,246), and multiplying the remaining 1990 US
                   Census population (31,518) by an average of 55 gallons per day. By this method, private water use
                   is 1.7 million gallons per day.

                   Poultry
                   The State Water Control Board estimates that a chicken uses 0.09 gallons of water per day (SWCB,
                   Bulletin #60, 1983). With a 1990 production of 21 n-dllion chickens and an average 45 day life span,
                   on any given day there were 2.6 n-dllion chickens, and these consumed a total of 234,000 gallons per
                   day (0-234 MGD)- This is roughly close to the permitted withdrawal rate for the Town of
                   Onancock.

                   While it would seem safe to assume that chickens consume the same quantity of water today as
                   they did in 1983, current practices may have increased the poultry water use. In the summer of 1991,
                   temperatures hovering around 100*17 for several days in a row caused widespread mortality among
                   chickens on the Delmarva Peninsula. Chicken growers reported trying the technique of misting the
                   chickens with water and blowing fans on them to keep their body temperatures down (The
                   Washington Post, July 25,1991, Section B). This new procedure may or may not use significant
                   quantities of water, and it may be unique to rarely hot years; nevertheless, it may account for an
                   increase in water consumption attributed to poultry.

























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                                                                   2-23









                                    Figure 2-10: Industrial Water Withdrawals vs. Permitted Amounts
                                                    Eastern Shore of Virginia, 1985-1990


                                       16-


                                       14-
                                                                                               -0- Ind. Withdrawal
                                       12-                                                         Permitted

                             0         10-




                                       6-


                                       4-


                                       2-


                                       0
                                       1984   1985   1986    1987   1988   1989   1990   1991


                                                                Years
                   Source: Virginia State Water Control Board
                    Note: All of the industrial withdrawals were permitted prior to 1985.




                                       Figure 2-11: Public Water Withdrawals vs. Permitted Amounts
                                                    Eastern Shore of Virginia, 1985-1990


                                       16-


                                       14-

                                       12-                                                     -0- Pub. Withdrawal
                                                                                               -*- Permitted
                                       10-                                         -----


                                       0-


                                       6-
                                       4                                           At*-

                                       2-


                                       0--
                                       1984        1986         1988        1990         1992


                                                                Years
                  Source: Virginia State Water Control Board





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                                                                    2-24







                                 Figure 2-12: Public and Industrial Withdrawals vs. Total Permitted
                                                Eastern Shore of Virginia, 1985-1990


                                   16-


                                   14 - -------                               - - -----


                                   12--
                                           0--010,                                       -0- Withdrawals
                                   10-                                                   -0- Permitted

                                     8-


                                     6-


                                                                        ---------------------------
                                     4


                                     2


                                     0
                                     1984      1986        1988       1990       1992


                                                           Years
                  Source: Virginia State Water Control Board



                                Figure 2-13: Public and Industrial Water Withdrawals by Month, 1990
                                                     Eastern Shore of Virginia


                                   100-
                                   90 4L

                                   80 -
                                   70                         ----A                      PUBLIC
                                   60                                                    INDUSTRIAL

                                   so-                                   ------

                                   40                   ------ ----

                                   30 -

                                   zu

                                   10

                                     0
                                      Jan Feb Mar AprMayjun Jul Aug Sep Oct Nov Dec

                                                         MONTHS
                  Source: Virginia State Water Control Board





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                                                               2-25




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                               CONTAMINATION THREATS
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                   SECTION 3 - CONTAMINATION THREATS


                   In order to formulate an effective ground water protection strategy, it is necessary to analyze past,
                   existin& and potential land uses. Sources of contamination must be assessed in order to be able to
                   answer questions about present conditions and to make predictions about the long-term viability of
                   the water supply. Because monetary resources are often limited, localities must prioritize their
                   efforts by addressing those contaminant sources of most concern. In this section, several categories of
                   potential contaminants such as waste water disposal, agriculture, industry, solid waste disposal,
                   and septage disposal are examined.

                   Almost all of the ground water quality threats identified in the following section will have an
                   impact on the Columbia aquifer on the Eastern shore. These land use threats discharge
                   contaminants directly to the land surface or shallow ground water system. Only where public water
                   supplies receive recharge from the Columbia aquifer would these threats be possible sources of
                   contamination to those drinking water supplies. Many older wells serving private homes were
                   drilled into the Columbia aquifer, and the threats outlined here are pertinent to owners of those
                   wells.

                   Sources of contaminants can be broken down into two general categories: point source and non-point
                   source. Point sources refer to easily-identified sources of contamination that typically concentrate
                   waste discharges into a single point, such as sewage treatment plants and certain industrial
                   discharges. Nonpoint sources refer to widespread sources of contamination which present
                   significant threats to ground water quality. Road runoff drainage is an example of a nonpoint source
                   of contamination to ground water. Many of these sources exist without specific discharge permits
                   and water quality monitoring requirements. Individually, each source may not represent a serious
                   threat to ground water supplies, but cumulatively they may. Most of the potential contamination
                   on the Eastern Shore falls into the non-point source category.

                                     Figure 3-L Typical Sources of Contamination to Ground Water





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                        Ground Water Supply Protection and Managernent Plan for the Eastern Shore of Virginia

                                                                  3-1










                   WASTE WATER DISPOSAL

                   The majority of residents (92%) on the Eastern Shore of Virginia use private septic systems for
                   discharge of household waste water (HWH calculations based on 1990 US Census). Two towns on
                   the mainland of Virginia's Eastern Shore have public sewage systems. Larger facilities, such as
                   industries, restaurants, and hospitals have permitted treatment facilities or are able to discharge
                   waste into mass drainfields.


                   Public Sewage Systems

                   At present, there are only three incorporated towns with public sewage facilities. The towns of
                   Onancock, Cape Charles, and Tangier Island have facilities which serve approximately 659
                   residents on Tangier Island and 1,398 in Cape Charles. It is unclear how many additional residents
                   are served outside of Onancock's town population of 1,434. According to the Northampton Country
                   Comprehensive Plan (1990), the Exmore/Willis Wharf area is planning to construct a central sewer
                   system which would serve approximately 2,684 people. In addition, sewering is anticipated for the
                   DeCanio property, and Northampton County now requires central sewage facilities for any large-
                   scale development (County Planner, John Humphrey,1990).

                   The three sewage systems are designed to discharge at rates ranging from 100,000 to 250,000 gallons
                   per day. It is estimated that town facilities are the largest sewage discharge systems in the two
                   counties, other than the two poultry industries, Perdue Inc. and Holly Farms.

                                                   Table 3-1: Public Sewage Facilities

                                                          Recehd= Stream                         Design Flow (MGD)
                       Onancock@                        N. Branch-of Onancock Creek                             0.25
                       Tangier Island                   Chesapeake Bay                                          0.10
                       CaI26- Charles                   CaM Charles Harbor                                      0.25


                   From a ground water quality point of view, these sewage facilities present very little threat to the
                   resource since they discharge to surface bodies of water at the coasts rather than on land.
                   Discharged water is not available for recharge to the surficial aquifer or to the deeper confined
                   aquifers. However, these sources clearly present potential threats to estuarine water quality.

                   On-Site Septic Systems

                   Septic systems are the leading contributor to the total volume of waste discharged directly into the
                   ground (more than a trillion gallons annually from residents in the U.S.), and according to the US
                   EPA (1986), septic systems are the major source of ground water contamination. Contaminants
                   introduced from septic systems include nitrate-nitrogen, coliform bacteria, viruses, and a variety of
                   organic and inorganic chemicals from household products. In addition, sixty percent (60%) of the 23
                   n-dllion residential septic tanks in the United States are believed to be operating improperly
                   (Weigmann and Kroehler, 1988).

                   Septic systems are comprised of a septic tank, distribution box, and a leaching facility. The septic
                   tank provides for the separation of solids and liquids, during which time some waste is treated.
                   The distribution box funnels waste to the leaching facility, where the liquid water is deposited
                   into the soil. If septic tanks are not properly maintained by pumping every few years, solids may
                   pass to the leaching facility causing plugging, backups into the dwelling, or breakouts of effluent on



                        Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                    3-2








                   the land surface. Once this has occurred, corrective actions are expensive and may result in ground
                   water contamination if septic cleaners containing solvents are utilized.

                                       Figure 3-2. Septic System and Ground Water Contmiination


                                                                      Evapotranspiration
                                        Well

                                                                                       Leaching
                                                              Fft     Uz@!;@ Za --"    Field
                                                Septic Tank"
                                                                                     Soil Adsorption
                                                             Distribution
                                                             Box
                                                                                z.:Z  Biological
                                               Unsaturated Zone                        Treatment


                                                             "O@e
                                                ---Water
                                                                              und


                                                                               MR.

                                           . . . . . ........
                   Conventional septic systems provide only minimal treatment of wastewater, and release effluent
                   contains approximately 40-60 mg/I nitrogen. As the effluent n-dxes with ground water and moves
                   downgradient, the nitrogen becomes more dilute. Given local geologic conditions, a flow distance of
                   several hundred feet is required to reduce concentrations to meet the drinking water standard of 10
                   mg/I for nitrate-nitrogen (see Section 9). The cumulative effects of numerous small septic systems
                   may result in excessive nutrient concentrations in ground water and downgradient surface waters.
                   These impacts are dependent upon locations of septic systems relative to wells and the overall
                   septic system density.
                   As noted above, the public sewer systems on the Eastern Shore of Virginia serve just over 3,000
                   people out of a total of 44,000, and the majority of residents use private septic systems to dispose of
                   human waste. In a 1986 study, the Virginia Water Project estimated that there were 12,105 year-
                   round housing units in Accomack County and 5,008 in Northampton County which had septic tanks,
                   cesspools, or other sewage disposal means (not public). It was also estimated that in both counties
                   there was a total of 1,359 homes with failing or inadequate disposal systems. The results are
                   summarized in the following table.

                                            Table 3-2: Residential Disposal of Septic Wastes

                                                     Year-round Housing Units                 Estimated GPD
                       ACCONMCK COUNTY
                       Served by public sewer                          1,044                         156,600
                       With septic tank or cesspool                   10,077                        1,511,550
                       With other sewage disposal means                2,028                         304,200

                       NORTHANCPTON COUNTY
                       Served by public sewer                             934                        140,100
                       With septic tank or cesspool                    3,948                         592,200
                       With other sewage disposal means                1,160                         174,000

                       IMAI.                                          191%                         2,878.65
                       Source: Water For Tomorrow, Virginia Water Project, Inc., 1988
                                              aSeptic Tank
                                                             Distd@














                        Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                     3-3








                  Based on calculations from the nitrogen loading section (Section 8), approximately 381,000 pounds of
                  nitrogen are discharged to the ground water of the Eastern Shore from on-site septic systems per
                  year.

                  Proper maintenance of septic systems includes periodic pumping of solids (septage) from the tank.
                  On the Eastern Shore, the contents are brought to one of three privately-owned septage lagoons.
                  These are described later in this section.

                  Virginia Pollution Discharge Elimination System (VPDES) Permits and Mass Drainfields

                  There are numerous industries that are required to obtain a discharge permit in order to dispose of
                  wastewater. According to State Water Control Board Regulations, those applying for land
                  application of sewage, sludge, or industrial waste must obtain a Virginia Pollution Abatement
                  Permit (VPA). Discharging of pollutants from a point source to surface waters requires a Virginia
                  Pollution Discharge Elimination System (VPDES) Permit. The major VPDES dischargers on the
                  Eastern Shore of Virginia are Holly Farms, Perdue, and the Wallops Island Flight Facility. The
                  remaining establishments have small design flows. Table 3-3 lists those industrial and public
                  VPDES permit holders.

                  There are 76 facilities that dispose of waste water in mass drainfields. Mass drainfields are
                  simply larger septic systems that are shared by more than one building, residence, or industry. Such
                  facilities typically include restaurants, schools, and campgrounds, however they can also be
                  associated with several single family residences. The discharge rates of these facilities are not
                  high; in fact, combining all these facilities would not equal the discharge rate in gallons per day of
                  Holly Farms alone. Table 34 identifies these facilities.


                  AGRICULTURE

                  Agricultural practices introduce two "s of contaminants, pesticides and nitrate-nitrogen from
                  fertilizers and livestock. These chen-dcals can pose serious threats to human health in excessive
                  concentrations. Nitrates are particularly dangerous to infants. Ingesting too much nitrate-nitrogen
                  can result in methemoglobinen-da, or "blue baby syndrome". Asphyxiation can occur when the
                  nitrate-nitrogen that is ingested is reduced to nitrite and is absorbed into the circulation system.
                  Nitrite reacts with hemoglobin to produce a compound that does not carry oxygen, thus depriving an
                  infant of oxygen. The EPA recommends that nitrate-nitrogen levels in drinking water be less than
                  10 mg/l.

                  The serious toxicity of pesticides has been widely reported in the cases of Agent Orange and DDT.
                  On the Eastern Shore where private wells are commonly less than 300 feet deep, one pesticide,
                  Aldicarb or Temik, has been detected in drinking water (Weigmann and Kroehler, 1988). Aldicarb
                  is highly soluble and mobile in water. Agent Orange and DDT were banned decades ago. Aldicarb
                  is no longer used.

                  Fertilizers

                  High application rates of commercial fertilizers over large areas of land have been shown to
                  contribute nitrogen to the ground water in an agriculturally intensive region like the Eastern Shore.
                  Publications and studies supporting this hypothesis are numerous. For reference, a selection of
                  examples include: USGS, 1989, p. 38; EPA, 1990, pp. 125-128; Association of Ground Water
                  Scientists and Engineers, 1989, p. 262; Miller, David A., 1980, pp. 430-431; Ground Water Quality



                       Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                    34







                    Protection, State and Local Strategies, 1986, p. 84, p. 145; Ground Water Pollution News, 1989,pp. 1-
                    2. However, as stated on page 14 of this document, the average nitrogen concentration in the
                    ground water was calculated to be 2.0 n-dlligrams per liter. The national drinking water standard
                    for nitrogen is 10 milligrams per liter. On the average, the shallow ground water quality is
                    considered very good, however users down gradient from high nitrogen use may experience
                    problems.
                    Farmers generally follow recommended fertilizer application amounts. This makes it possible to
                    estimate the quantities of nitrogen fertilizers applied to each crop type. Using 1990 crop acreage
                    figures, agricultural practices required approximately 5.8 million pounds of nitrogen in fertilizers.
                    Table 3-5 presents a breakdown of nitrogen requirements by crop type. Approximately 6.7% of the
                    land is fertilized with manure; the remainder is supplied by commercial fertilizer (Accomack
                    County Extension Agent, J. Belote, personal communication, 1991). Out of a total of 165,000 acres of
                    farmland, 94,000 are used for soybeans, a crop which requires no nitrogen fertilization because the
                    plant is a nitrogen-fixer.
                    Current methods for the Eastern Shore recommend that fertilizer be applied in two stages: a small
                    amount at planting, the rest after growth occurs. In the case of corn, this second application occurs
                    when the plant has reached ankle height. The fertilizer is side-dressed, which means that it is
                    dribbled on each TOw at each plant, so that a small amount is wasted in the soil. With the
                    implementation of side-dressing and the new phased technique, the intention is to hold leaching of
                    nitrogen to a minimal amount. However, USGS sampling that is representative of current and/or
                    recent fertilization practices shows a concentration of 20-25 n-dlligrams per liter (mg/1) nitrate-
                    nitrogen in ground water beneath farm fields in the shallow flow system (G. Speiran, USGS,
                    personal communication, 1991).
                    Historically, the number of farmers and the acres farmed have been declining since 1930. The type
                    of crops grown has also changed. Whereas crops grown in the earlier half of this century were of
                    the garden vegetable kind and required fertilizers, today's crops are mainly soybeans and are not
                    fertilized. Still, significant amounts of fertilizers are presently used, as shown in Table 3-5. Also,
                    both the Accornack and Northampton County Comprehensive Plans see agriculture as continuing to
                    be the main land use in the future. Thus, although nitrogen fertilizer use has been decreasing, it
                    remains relevant to look towards agriculture as a potential source of contan-driation to ground water,
                    both from former and current practices. For this study, 89 and 79 lbs/acre were used as average
                    nitrogen application rates in Accomack and Northampton counties respectively.
                    On a smaller scale, home owners in general use fertilizers as a part of lawn maintenance. Nitrogen
                    loading from lawn fertilizers was studied by Nelson et al. in 1988. They detern-dned that, on
                    average, the homeowner applies 3 lbs. of nitrogen for every 1,000 square feet of lawn per year.
                    With a leaching rate of 30%, 0.9 lbs. of nitrogen are leached into the ground water system for every
                    1000 square feet of lawn. On the Eastern Shore, lawn maintenance is not a high priority.

                    Pesticides

                    Pesticides include a wide variety of chen-dcals utilized for the control of animal pests, insects,
                    fungi, and weeds. Factors which affect the level of risk for contan-tination include the specific
                    chen-dcal formulation, rates of application, timing of application, soil conditions, and hydrologic
                    conditions. Those that have a low solubility, are degraded by sunlight, or react with water to
                    produce new compounds are not likely to contaminate ground water.





                         Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
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                                                                                                  Table 3-3:     Facilities With Discharge Permits, Eastern Shore, Virginia

                     C)         Accomack County                                                                                                                                                                         Plant Outfall               Flow (MGD)
                                Facility Name                                        Ind/Mun      VPDES#             C11                    Receiving Stream                                                             Latitude     Longitude         Design
                                Accomack Co. Nursing Home                            M            VA0063606                                 N. FORK PARKER CREEK TO METOMPKIN BAY                                          374537          753719               OR2
                                Bonawell Brothers Seafood                            I            VA000420i          Saxis                  POCOMOKE SOUND                                                                 375515          754350           *.001(4)
                                Chincoteague Fish Co.                                I            VA0051462          Chincoteague           CHINCOTEAGUE CHANNEL                                                           375600          752254
                                Chincoteague WTP                                     I            VA0051756          Chincoteague           CHINCOTEAGUE CHANNEL                                                           375605          752239
                                Drewer & Son, Inc.                                                                                                          REEK                                                           375512          754351      *.035,.018(4)
                                                                                     I            VA0081361          Saxis                  STARLING C
                                Edgerton, D. 1. Fish Co.                             I            VA0055239          Chincoteague           CHINCOTEAGUE CHANNEL                                                           375612          752227               *161
                                Edgewood Mobile Home Park                            M            VA0065196          New Church             TRIB TO TUNNELS MILL BR TO BULLBEGGER CRK                                      375709          753216             0.006
                                External Assist. Sys. Pension Trust                  M            VA0078204          Route 13               TRIB TO TUNNELS MILL BR TO BULLBEGGER CRK                                      375655          753238             0.035
                                F&G Laundromat                                       I            VAOD50M            Chincoteague           CHINCOTEAGUE CHANNEL                                                           375600          752200            *0.005
                     lu         Fisher, Lance G. Seafood Co., Inc.                   I            VAM79448           Sanford                POCOMOKE SOUND                                                                 3755W           754130            *.02(4)
                                Hills Oyster Farms                                   I            VA0058874          Chincoteague           DEEP HOLE CREEK TO LITTLE OYSTER BAY                                           375612          752057
                                Ifolly Farms                                         I            VA0004049          Temperanceville        SANDY BOTTOM BRANCH TO HOLDENS CREE
                                                                                                                                                                                                          K                375325          753339               098
                                Kuzzens, Inc.                                        I            VA0081809          Painter                DITCH TO TAYLOR BRANCH TO OCCOHANNOCK CRK                                      373352          754803
                                Lewis Oyster Co.                                     I            VA0057673          Saxis                  STARLING CREEK TO POKOMOKE BAY                                                 375511          754353 'no discharg
                     ;%         Marshall, William H. & Co.                           I            VA0058360          Greenbackville         CHINCOTEAGUE BAY                                                               380022          752326
                                McCready Seafood                                     I            VA0095690          Chincoteague           EEK CREEK TO CHINCOTEAGUE BAY                                                  375546          752232 'no discharge
                                Messick & Wessells - Nelsonia                        I            VA00514ff-         Nelsonia               MUDDY CREEK                                                                    374916          753515            *0-005
                                Messick & Wessells - Onley                           I            VA00539W           Onley                  JOYNES BRANCH TO ONANCOCK CREEK                                                374134          754244            *0.005
                                Nandua Seafood Co., Inc.                             I            VAOD51161          Hacksneck              BACK CREEK TO NANDUA CREEK                                                     373802          755252
                                New Curch Energy Associates                          I            VA0058521          NewChurch              UNNAMED TRIB TO PITTS CRK & POCOMOKE SOUND                                     375858          753254
                                North Accomack Elem. School                          M            VA0027162          Mappsville             UNN. TRIB TO MESSONGO CREEK TO POCOMOKE BAY                                    375128          753357             0.5F9
                                Onancock WTP                                         M            VA0021253          lonancock              N. BRANCH OF ONANCOCK CREEK                                                    374258          75"52                025
                                Perdue, Inc.                                         I            VA0003NO           Accomac                PARKER CREEK TO METOMPKIN BAY                                                  374410          753920         *1.7,.01(4)
                                Reed, Thomas E. - Seafood, In.                       I            VA0005738          Chincoteague           DEEP HOLE CREEK                                                                375621          752045               1611
                                Russell Fish Co.                                     I            VA0054003          Chincoteague           CHINCOTEAGUE CHANNEL                                                           375559          752255               *161
                                South Accomack Elem. School                          M            VA0027171          Melia                  UNNAMED TRIB TO WAREHOUSE POND                                                 373920          754738             0.009
                                Stubbs, Reginald - Seafood Co, Inc.                  I            VAOD56421          Chincoteague           ASSATEAGUE CHANNEL                                                             375501          752224           6.002(4)
                                Tangier WTP, Town of                                 M            VAOD67423          Tangier                Cl IESAPEAKE BAY                                                               374940          760035               0.1
                                Taylor, I.W. - Packing                               I            VAOOOZM            Hallwood               MESSONGO CREEK TO POKOMOKE SOUND                                               375224          753529               0.1
                                Taylor & Fulton, Inc.                                I            VA0082538          Mappsville             UNNAMED TRIB OF ASSOWOMAN CRK TO ASSOWOMA                                      375216          753319
                                US - NASA Wallops Flight Facility                    M            VAOD24457          Wallops Island         HOG CREEK AND MOSQUITO CREEK                                                   375550          752859        0.8 & 0.03
                                Vasiliou, Tom - STP                                  M            VA0082297          Oak Hall               TRIB TO TUNNEUS MILL BR TO BULBEGGER CRK                                       375649          753233             0-001
                                VDOT - Rt. 13 Information Center                     M            VA0023078          New Church             TRIB TO PITTS CREEK                                                            375927          753213               O.F2
                                VDH - Septage Lagoon - Boggs 01                                   VDHSLBO-01         Wachs rea        ue    eventually to Nickawampus Crk. to Finney Creek                                 373738          754222
                                VDH - Septage Lagoon - Bundick 01                                 VDHSLBU-01         Atlantic                         to Little Mosquito Creek                                             375538          753158
                                VDH - Septage Lagoon - Bundick 02                                 VDHSLBU-02         Mappsburg                       to Machipomgo River                                                   373405          754611
                                Virginia Carolina Seafood Co., Inc.                  I            VA0050997          Chincoteague           WATTS BAY                                                                      375432          7528311
                     !4*        Watkinson, Paul - Seafood                            I            VA0050491          Saxis- POCOMOKE SOUND                                                                                 375511          754354
                              [WWis-pering Pines Motel                                           IVAOMM71            ITicktown            JUNNAMED TRIB TO DEEP CREEK                                                      374 20          7541411              019












                                                                                              Table 3-3.    Facilities With Discharge Permits, Eastern Shore, Virginia
                    C)         Northampton County
                               Facility Name                                     Ind/Mun      VPDES#            City                 ReceivinIt Stream                                                       Latitu e       ongiiude       Design
                               America House Motor Inn                           M            VA0064921         Cape Charles         CHESAPEAKE BAY                                                              370813        755807               0.02
                               American Original Corp.                           I            VA0029M           Willis WharF- PARTING CREEK TO MACHIPONGO RIVER                                                  373045        754824           *.151(4)
                               Ballard Fish & Oyster Co.                         F            VA0073679         Cheriton             KINGS CREEK                                                                 371658        760039
                               Bayshore Concrete Prod. - Cape Chad.              I            VA008%77          Cape Charles         CAPE CHARLES HARBOR                                                         371541        760131
                               Bell, B.L. & Son                                  I            VAOM4219          Oyster               OYSTER HARBOR                                                               370-09        755532
                                                                                                                                                                                                                                                 .001(4)
                               Broad Street Laundry                              I            VA0056502         Exmore               UNNAMED TRIB TO NASSAWADOX CREEK                                            373138        7549301
                    z          BFoadwater Bay Seafood                            I            VA0086126         Marionville          REDBANK CREEK TO I IOG ISLAND BAY                                           372644        755033
                    :9         C&D Seafood                                       I            VA0002917         Oyster               OYSTER HARBOR                                                               371715        755520    stopped d is.
                    q1-        Cape Charles Fish & Scallop, Inc.                 I            VA0083283         Cape Charles         CAPE CHARLES HARBOR                                                         371548        760100
                               Cape Charles STP                                  M            VA0021288         Cape Charles         CAPE CHARLES HARBOR                                                         371550        760100               0.25
                               Cheriton Laundry, Inc.                            I            VA0051136         Cherilon             TRIB TO KINGS CREEK                                                         2M2           755735
                               Eastville Laundromal                              I            VA005"37          Easiville            OLD CASTLE CREEK                                                            3720381       755716
                               Hamblin, I.E. - Seafood                           I            VAOO&%93          Willis Wharf         PARTING CREEK TO MACHIPONGO RIVER                                           373130        754815 'no discharge
                               KMC Foods, Inc.                                   I            VA0054119         Cherilon             HANDY BRANCH                                                                371744        755733
                               Machipongo Elem. School                           M            VA0023817         Machipongo           UNNAMED TRIB TO JACOBUS CREEK                                               372429        755458            0.0208
                               Northampton-Accomack Memorial Hosp.               M            VA0027537         Nassawadox           WAREHOUSE CREEK TO NASSAWADOX CREEK                                         372839        755144                0.1
                               R&C Seafood Co.                                   11           VA0052264         Oyster               OYSTER SLIP                                                                 371715        755515
                               Terry, H.M - Co., Inc.                            if           @MT9K             Willis Wharf         PARTING CREEK TO MACHIPONGO RIVER                                           373037        754821          -.0004(4)1
                    1:5        West, John H.                                     11           VA0083437         Oyster               OYSTER HARBOR                                                          1    3717141       7555

                               Source:      figure comes from the Water Quality Mgt. Plan, SWCB,                            NOTE: (2) NPDES permit limits (1980)
                               1980. The remaining numbers are up to date (1991) from the SWCB. They                                 (4) Estimated
                               do not have flows for industrial facilities except Holly Farms and Taylor Packing.                    (6) No limits - has an NPDES permit, but is not required to monitor (things like crab shedding)









                                     Table 3-4: Facilities Using Mass Drainfields, Eastern Shore, Virginia

                                           FACILITY NAME                            TOWN              gallons per day


                               ACCOMACK COUNTY
                               Virginia Landing                               Quinby                         90000
                               Tom's Cove                                     Accomack County                N/A
                               Trail's End Chincoteague Bay                   Horntown                       20000
                               Inlet View/Bunker Hill                         N/A                            N/A
                               Maddox Family Campground                       Chincoteague                   N/A
                               Pine Grove Campground                          Chincotea ue                   N/A
                               Island Motor Inn                               Chincoteague                   6400
                               Refuge Motor Inn                               Chincoteague                   8800
                               Driftwood Motor Lodge                          Chincoteagu                    6700
                               Chincoteague Motor Lodge                       Chincoteague                   9360
                               Waterside Motor Inn                            Chincoteague                   5700
                               Conner & McGee                                 Chincoteague                   3300
                               Eastwind Townhouse                             Chincoteague                   9600
                               Assateague Inn                                 Chincoteague                   4040
                               Don's Seafood Market & Restaurant              Chincoteague                   4000
                               Seatag Lodge                                   Chincoteague                   3000
                               Birchwood Motel, Inc.                          Chincoteague                   wo
                               Mulberrv Street Townhouse                      Chincoteague                   %00
                               David P. Burgess Townhouse                     Chincoteagu                    2700
                               R&S Drv Cleaning & Laundry                     Chincoteague                   N/A
                               McDonald's                                     Chincoteague                   4000
                               ETTAS Restaurant                               Chincoteague                   4300
                               Landmark Crab House                            Chincoteague                   12500
                               R&S Laundromat                                 Chincoteague                   5500
                               Mr. Chocolate Island Creamery                  Chincoteague                   4500
                               Oak Ridge Townhouse                            Chincoteague                   9000
                               Reed Triplexes                                 Chincoteague                   2700
                               Chincoteague High School                       Chincoteague                   4000
                               Chincoteague Elementary                        Chincoteague                   2000
                               Parks Mobile Park                              Oak Hall                       7200
                               Pizza Hut                                      Oak Hall                       2500
                               Arcadia High School                            Accomac                        6912
                               Wright's Seafood Restaurant                    Atlantic                       5000
                               Eastern Shore Seafood Production               Mappsville                     1500
                               Bvrd Foods                                     Mappsville                     2000
                               Parkslev Middle School                         Parksley                       2000
                               Red & 'White Stores                            Parksley                       1500
                               St. Paul's Lutheran School                     Hallwood                       3000
                               Bi Countv N.H. Nursing Center                  Gargatha                       6400
                               Accomac Office Complex                         Accomac                        %00
                               Mary N. Smith Middle School                    Accomac                        6000
                               Nandua High School                             Onley                          13826
                               Redwood Gables Restaurant                      Onlev                          1800
                               Chesapeake Square Shopping Center              Onlev                          12000
                               Four Corners Plaza                             Onley                          12000
                               Eastern Shore Comm. College                  -.Melfa                          12000
                               Ches-Atlantic                                  Painter                        1500



                           Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                             3-8









                                 Table 3-4: Facilities Using Mass Drainfields, Eastern Shore, Virginia

                                               FACILITY NAME                                  TOWN          gallons per day

                                 Exmore Moose Lodge                                Belle Haven                     5000
                                 Kuzzen's Ames Farm/ MLC                           Painter                         10500
                                 Peerless Sterling Bull Camp                       Modest Town                     1200
                                 Peerless Sterling Gargatha                        Temperanceville                 4500
                                 Peerless Sterling Somers Farm                     Bloxom                          4500
                                 Peerless Sterling Lakeview                        Accomac                         2600
                                 Taylor & Fulton Inc.                              Hallwood                        9000
                                 Taylor & Fulton Poulson House                     Hallwood                        1500
                                 Virginia Farms/ Farm Exchange                     Taslev                          1500
                                 Ravmond A. Last-VPDES                             Chin oteague___                 7650
                                 Willett's Laundromat-VPDES                        Lee Mont                        3200


                                 Accomack TOTAL                                                                   394988


                                 NORTHAMPTON COUNTY
                                 Cherrystone Holiday KOA                           Northampton Co.
                                 Paul's Restaurant                                 Cheriton                        3500
                                 Capeville Campground                              Northampon Co.                  7500
                                 Cheriton Day Care                                 Cheriton                        2000
                                 Trawler Seafood Restaurant                        Exmore                            700
                                 Hardees                                           Exmore                          2500
                                 Silver Beach Camping                              Silver Beach                    2700
                                 Broadway Academy                                  Exmore                          3000
                                 McDonald's                                        Nassawadox                      4500
                                 Anchor Motel Restaurant                           Nassawadox                      7640
                                 Candlelight Restaurant                            Birdsnest                       5760
                                 Holidav Motel                                     Townsend                        18000
                                 Burger Unlimited                                  Eastville                       1500
                                 Curtis Jones & Son Packing Sh                     Eastville                       2240
                                 Kuzzens - Newman                                  Eastville                       1800
                                 Northampton High School                           Eastville                       16000
                                 Cape Center Inc.                                  Capeville                       2500
                                 Holidav Acres Mobile Home Park                    Weirwood                        4800
                                 Curtis Jones, Jr.                                 Bavford                         1550
                                 P.C. Kellam Potato Shed                           Bridgetown                      2000

                                 Northampton TOTAL                                                                 90190

                                 GRAND TOTAL                                                                      485178

                                 Source: Virginia Tech (N/A indicates information not available)









                             Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

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                   The primary crops grown on the Eastern Shore of Virginia are soybeans, small grains (wheat and
                   barley), potatoes, a variety of garden vegetables, and some ornamental plants. Several different
                   types of pesticides are used depending on the pest, crop type, and application requirement. These
                   factors significantly vary from farm to farm. Since there is no formal reporting of pesticide use,
                   other than that of restricted-use pesticides, it is impossible to sum-dse the quantities and brands
                   that are applied each year. As such, it need be stressed that the leaching of pesticides into the
                   ground water is a threat to water quality and should be monitored.

                   Animal Wastes and Animal Carcasses

                   Animal wastes can contaminate ground water with nitrate-nitrogen and bacteria. In 1990, 21
                   million chickens were raised for poultry on the Eastern Shore of Virginia. Commercial poultry is
                   the only significant livestock industry in the area, and is contained entirely within Accomack
                   County. Commonly, contan-tination results from feedlots and improperly constructed or leaking
                   manure storage piles or pits. Eastern Shore chicken growers apparently do not store wastes in such
                   piles, but instead clean the chicken houses out once or twice yearly whereupon the manure is spread
                   onto the farm land.

                   The Virginia State Extension Service reports that for every thousand chickens, one ton of poultry
                   manure is produced (W. Weaver, Virginia Tech, personal communication, 1991). Tests done by
                   Perdue and Tyson of 57 poultry litter samples indicate that nitrogen constitutes 44.73 pounds per ton
                   of manure (Virginia Tech, 1991). Therefore, in 1990,21,000 tons of poultry manure was produced,
                   contributing a total of 940,000 pounds (470 tons) of nitrogen. During the year or so that manure
                   remains in the chicken houses, some of the nitrogen volatizes. However, on a weight basis, chicken
                   manure has the highest nutrient availability rate, compared to that of horse, cattle, and hog
                   manure. While this makes it a good fertilizer, it is also most easily leached into ground water.

                   In large quantities, chicken carcasses can also pose a threat to ground water quality. A natural
                   mortality rate of about 5% creates a need to dispose of dead chickens. Assun-dng that the majority
                   of chickens die within the first two weeks after hatching, mortality of dead birds can be split
                   between those that die at 0.5 lbs. and those that die weighing 3 lbs (C. Larsen, Virginia Tech
                   Veterinary Medicine, personal communication, 1991). A 5% mortality rate accounts for 1.05 million
                   dead birds in a year with a population of 21 n-dllion chickens. Multiplying half of those by 0.5 lbs.
                   and half by 3 lbs. gives a yearly rate of 1.84 million lbs. of dead birds. Dead chickens are disposed
                   of in one of four ways: burial, incineration, composting, or rendering for use as chicken or hog feed.
                   In Accomack County, the Tyson rendering plant is available for growers. The facility is used by
                   growers primarily during times of abnormally high mortality. An estimated 400,000 lbs. are
                   brought to the rendering plant per year, but there is no data to support this. The one facility that
                   had been incinerating has decided to compost, since it is more econon-dcal (J.R. Lewis, SCS, personal
                   communication, 1991).The majority of dead birds are thus either buried or composted. Burial (or
                   dumping in the woods, in some cases) poses a threat to ground water quality. Section 9 briefly
                   discusses composting.












                        Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                    3-10









                                                Table 3-5: Nitrogen Fertilizer Requirements, Eastern Shore
                                                                         of Virginia
                                                ACCOMACK COUNTY


                                                      Crop Type         1990 Acreage Recorarnended lbs. N Used
                                                                                         N in lbs/acre
                                                Soybeans                    62,000             0                0
                                                Corn                        51500            75-175          687,500
                                                Small grains                25,000           50-80         1,625,000
                                                Irish potatoes              5,500              150           825,000
                                                Sweet potatoes              1,600            W7-5            100,000
                                                Talked tomatoes             2,200'           80-90           187,000
                                                Snap beans (Spring)         1,000            40-80           60,000
                                                Snap beans (Fall)           2,300            40-80           138,000
                                                Cucumbers (Spring)          1,000            100-125         112,500
                                                Cucumbers (Fall)            2,000            100-125         225,000
                                                Others                      2,500            50-150          2.50,000
                                                Ornamentals                  700
                                                Grapes and Orchards          120

                                                Accomack Total              47,420                         4,210,000
                                                N applied acres
                                                Average N Application (lbs/acre)*              89

                                                NORTHAMPTON COUNTY

                                                     Crop Type          1990 Acreage Recommended lbs. N Used
                                                                                         N in lbstacre
                                                Soybeans                    32,000             0                0
                                                Corn                         500             75-175          K2 500
                                                Small grains                12,000           50-80           780,000
                                                Cotton                      1,300              60            78,000
                                                Potatoes                    2,500            50-150          250,000
                                                Snap beans (Spring)          600             40-80           36,000_
                                                Snap beans (Fall)            600             40-80           36,000-
                                                Zucumbers (Spring)           8W              100-125         90,000
                                                Cucumbers (Fall)             800             100-125         90,000
                                                Tomatoes                     650             80-90           .55,2-50_
                                                Peppers                      100             100-130         11,500-
                                                Spinach                      280             100-125         31,500
                                                Nursery                      840       1                                                                       1
                                                10thers                1    1,000      1     50-150      1   100,000

                                                Northampton Total           20,570                         1,620,750
                                                N applied acres
                                                Average N loading (lbs/acre)*                  79

                                                TOTAL FERTILIZED            67,990                         5,830,750
                                                *Total Average Nitrogen Loading:               84
                                                (Calculated by subtracting out
                                                Spring Acres Double Cropped)

                                                Sources: Fact Sheet - Accomack County, 1989 National Survey
                                                of Conservation Tillage Practices, personal conversation with
                                                Northampton Extension Agent Fred Diem, 2/26/91


                             Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                                  3-11











                  IKDUSTRIAUCONUvEMCIAL LAND USES


                  Underground Storage Tanks

                  Petroleum stored in underground storage systems is one of the greatest national threats to ground
                  water quality. The EPA estimates that approximately one-third of all existing systems
                  nationwide are currently "non-tight", or potentially leaking. The average expected life span of
                  unprotected steel tanks in acidic soils is approximately 15 years, although new steel underground
                  storage tanks are warranted for 30 years. After time, corrosion may begin, resulting in pin-hole
                  sized leaks which may discharge hundreds of gallons of fuel over a several-month period. These
                  leakage rates are small enough to go unnoticed to the tank owner for several months, but are large
                  enough to cause significant ground water contamination problems. Gasoline contains a variety of
                  components including benzene, toluene, and xylene, all which are known to have negative health
                  affects. Newer tanks are being constructed with materials resistant to corrosion and with cathodic
                  protection, which is aimed at decreasing the likelihood of leakage.

                  A total of 1,154 underground storage tanks are located in Accomack and Northampton Counties. Of
                  these, 684 or (59%) are over 15 years old. The majority of all storage tanks store gasoline and are
                  made of steel. Together, they have a storage capacity of 4,462,347 gallons.


                     Figure 3-4. Underground Storage Tanks Broken Down By Age and Wellhead Protection Area,
                                                     Eastern Shore of Virginia


                                  200-


                                  175-


                                  150-
                                  125 -                                                   > 15 years
                                                                                          < 15 years

                                  100-


                                   75--


                                   sol
                            Z
                                   25-


                                    0--
                                       WPA A WPA B WPA C           WPA D    WPA E


                                                  Wellhead Protection Area
                  Source: Virginia State Water Control Board
                                                    rmiz








                       Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                3-12








                   Underground storage tanks were grouped by Wellhead Protection Area (WPA) in Table 3-6. WPA's
                   are introduced and described in Section 5. WPA C, which covers the largest land area, also has the
                   greatest number of underground storage tanks, with a total of 329. The remaining wellhead
                   protection areas all contain close to 200 tanks. The town of Chincoteague, located in WPA A,
                   contains 129 tanks which is the most located in any one town. WPA A also has the highest
                   percentage of storage tanks older than fifteen years.

                   State Water Control Board records indicate that there have been leakage problems in several
                   tanks in the two counties. Of the total, 3.6% of the tanks in Accomack and Northampton Counties
                   have been reported as leaking. As of July 3, 1991, there are twenty-nine contan-driated sites in
                   Accomack County, and twelve contan-dnated sites in Northampton County. A column in Table 3-6 on
                   the next page identifies the leaking tanks by town and wellhead protection area. WPA A has the
                   highest percentage of leaking underground storage tanks, with 9 out of 199 tanks leaking (4.5%).
                   According to the SWCB, seven tanks in Accomack County and one in Northampton County have been
                   closed and are no longer leaking. Only two tanks in Accomack County have a monitoring program
                   underway. It may be of interest to determine which of the leaking and non-leaking tanks lie on the
                   spine recharge area, and install monitoring programs for those tanks.


                   TO)CIC CHENUCALS

                   A wide variety of commercial and industrial land uses represent contamination threats to ground
                   water. Small scale businesses such as auto body shops or dry-cleaning establishments, which may
                   not be regulated by federal or state laws, utilize significant quantities of toxic chen-ticals such as
                   solvents. Accidental or inappropriate disposal of hazardous wastes, even in small quantities, may
                   result in ground water contamination exceeding state and federal drinking water standards. For
                   example, many of the drinking water standards for volatile organic compounds (VOC's) are in the
                   low parts-per-billion range.
                   Industries are required to report use and manufacturing of chen-dcals under several federal and state
                   laws. EPA's Toxic Substances Control Act (TSCA, P.L. 94-469) requires that all manufacturers or
                   importers of chemical substances be identified. Under the Superfund Amendments and
                   Reauthorization Act (SARA, 1986), specific chemicals and amounts used must be reported. In
                   Virginia, the Toxic Substances Information Act of 1976 requires that all businesses must report all
                   chen-dcals that are manufactured or used in the manufacturing process. Reports must be updated
                   annually.
                   On the Eastern Shore of Virginia, there are no Superfund or toxic dump sites. Several industries do
                   use toxic materials, however. Tables 3-7 and 3-8 identify these industries as reported separately to
                   the State and to EPA.














                        Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                 3-13









                                                                                       Table 3.6 UndwpvwW Storap Tudw by Wellhead P owedw Am

                                    WPA           TOWN                                 NUMBERS              TANX7YPE                                 PILOOLMT                     20OWS CAL             Act
                                    ACCOMACK COUNTY                         COUNT LEAKING STEEL FZL4SS UNKN. DIESEL                                  GAS X3ERO FZEL UjOIL CAPACITY 3-ISyn <15yn

                                    A             CHINCOTEAGUE                      129        2            126       2          1           9       54      11       32      1   --          ISL955    v          42
                                                  GREENBACKVILLE                    is         a            15        0          0           5       10      0        0       0               10.25     12         3
                                                  HORNTOWN                          12         0            12        0          0           0       4       0        8       0               10AS      10         2
                                                  NEW 01URCli                       20         3            20        0          0           3       13      1        1       0               90.9      9          11
                                                  WALLOPS STATION                   3          4            3         0          0           2       0       0        0       1               12M       3          0
                                                  WATTSVILLE                        20         0            20        0          0           2       is      1        2       0               8DA       10         10
                                                  total                             1"         9            196       2          1           21      %       23       63      2               3SL305    232

                                    a             ATLANTIC                          is         0            is        0          0           1       a       4        5       0               17M       11         7
                                                  HALLWOOD                          11         1            8         0          3           0       5       1        2       0               7AS       9          2
                                                  HORSEY                            1          0            1         0          0           0       1       0        0       0               1         0          1
                                                  MAPPSV1I..LE                      7          1            7         a          0           0       6       1        0       0               15.5      6          1
                                                  MEARS                             3          0            3         0          0           1       2       0        0       0               138       0          3
                                                  NELSONIA                          21         1            19        0          2           1       16      0        1       0               79.55     11         10
                                                  OAK HALL                          33         0            32        0          1           3       24      4        1       1               90.SS     11         22
                                                  TEhG%RANCBVM.LE                   36         2            34        0          2           8       16      1        5       3               16625     2S         11
                                                  WALLOPS ISLAND                    56         0            47        9          a           24      21      1        5       0               2137.132  40         16
                                                  WTrHAMS                           3          1            3         0          0           0       2       0        1       0               1.65      3          0
                                                  total                             189        6            In        ,          8           38  -101        12       29      4   1 2517M2              216        73

                                    C             ACCOMAC                           81         1            78        1          2           11      40      11       a       3               173.64    56         25
                                                  BLOXOM                            14         1            13        0          1           4       3       1        1       0               19.93     7          7
                                                  CENTERVILLE                       5          0            5         0          0           0               0        0       0               16        5          0
                                                  GREENBUSH                         7          0            6         0          1           1       6       0        0       0               41        6          1
                                                  LEEMONT                           4          0            4         0          0           0       2       1        1       0               2.4       4          0
                                                  LOCUSTVILLE                       3          0            3         0          0           a       2       1        0       0               1.22      3          0
                                                  MELFA                             31         1            30        0          1           6       23      1        0       0               60.2      16         24
                                                  ONANCOCK                          59         1            so        0          1           9       37      5        6       0               95.9      22         37
                                                  ONLEY                             41         2            40        0          1           4       26      4        3       2               106.8     26         is
                                                  PARKSLEY                          62         3            60        2          0           6       40      7        4       0               113.005   31         31
                                                  TASLEY                            22         1            21        0          1           a       a       2        0       2               37.925    16         6
                                                  -total                            329        10           318       3          a           45      197     33       23      7               631.62    192        2461

                                    D             BELLE HAVEN                       23         1            23        0          0           6       is      2        0       0               11d.08    12         11
                                                  CRADDOCKVILLE                     10         0            10        0          0           3       6       1        0       0               7.05      9          1
                                                  DAVIS WHARF                       4          0            4         0          0           1       3       0        0       0               2.6       0          4
                                                  KELLER                            is         a            13        0          2           2       9       2        0       1               24.63     a          7
                                                  MIDDLESEX                         3          0            3         0          0           2       0       1        0       0               20.5      0          3
                                                  PAINTER                           26         1            26        0          0           5       15      4        1       a               369       12         14
                                                  PUNGOTEAGUE                       5          0            5         0          0           0       5       0        0       0               zis       5          0
                                                  QUINBY                            4          0            4         0          0           1       3       0        0       0               2.65      0          4
                                                  WAQL4FREAGUR                      a          0            6         0          2           1       5       0        0       0               11.55     5          3
                                                  HARBORTON                         5          1            5         0          0           1       2       1        0       0               3.65      2          3
                                                  Rotal                             10ILS      3            %.S       0          4           21A     62      ILS      -I      I               mms       S2         4LS

                                    OUT of WPA SANFORD                              3                       3         0          0           0       2       1        0       0               im        3          0
                                    OUr of WPA SAXIS                                13         11           13        0          0           4       a       1        0       0               9.6       7          6

                                    COUNTYTOTAL                                     S36        29           an        24         21          L13     "7      71       207     14              37153V    S02        343

                                    NORTHAMPTON COUNTY

                                    D             BAYFORD                           4          0            4         0          0           1       2       0        a       0               2.2       2          2
                                                  BIRDS NEST                        3          0            3         0          0           0       2       0        1       0               1.1       2          1
                                                  BRIDGETOWN                        1          0            1         0          0           0       1       0        0       0               1         0          1
                                                  EXMORE                            77         4            71        3          3           10      53      7        2       2               142.04    45         32
                                                  JAMESVILIX                        4          0            4         0          0           a       1       0        1       0               2.2       4          0
                                                  NASSAWADOX                        27         0            25        0          2           2       14      3        1       a               62.03     14         13
                                                  SILVER BEAC3-1                    1          0            1         0          0           1       0       0        0       0               0.273     1          0
                                                  WEIRWOOD                          7          1            7         0          0           1       6       0        0       0               17.1      2          5
                                                  WFILLIS WHARF                     1          0            1         0          0           1       0       0        0       0               2         1          0
                                                  CHURCHNECK                        1          0            1         a          0           0       0       a        1       0               1         1          0
                                                  total                             126        5            its       3          5           16      79      10       6       2               230.943   72         54

                                    E             CAPE CHARLES                      84         2            so        1          3           16      47      9        3       0               2.26.25S  49         36
                                                  CAPEVILLE                         16         0            16        0          0           5       10      1        0       0               SIM       9          7
                                                  CHERMN                            30         2            30        0          0           2       24      3        1       0               67A3      11         19
                                                  CHESAPEAKE                        8          0            a         0          0           0       3       0        0       0               10        8          0
                                                  DALBYS                            3          0            3         0          0           0       2       1        0       0               am        1          2
                                                  EASIVILLE                         30         1            29        0          1           3       22      4        0       0               $6.94     14         16
                                                  MACHlPONG0                        12         1            12        0          0           1       10      1        0       0               30.05     7          5
                                                  SRAVIEW                           5          0            5         0          0           0       4       0        1       0               16M       5          0
                                                  TOWNSEND                          4          0            4         0          0           0       3       0        0       1               ism       4          0
                                                  total                             192        6            287       1          4           27      125     19       5       1   1           516.075   109        85

                                    COUNTYTOTAL                                     315        12           305       4          1           43      201     29       11      3               747.02    10         IN

                                    GRAND TOTAL                                     1254       42           1106      is         30          176     Gn      100      Ila     17              4"2.117   6n         4n

                                    Source Virgitua State Water Comrol Board


                                            Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                                                                             3-14











                    SOLID WASTE DISPOSAL

                    The predon-dnant form of solid waste disposal on the Eastern Shore is through landfilling. There
                    are currently two public landfills in Accomack County and one public and one private landfill in
                    Northampton County. Two additional landfills have been filled and are now closed. They are
                    located in Chincoteague and northern Accomack County. Incorporated towns in the Accomack-
                    Northampton Planning District utilize their respective county landfills for solid waste needs.
                    Locations of landfills in both counties are included in Figure 3-5.

                    The Northampton County landfill was opened in 1985 and is expected to be in service for 20 years.
                    It is located less than a mile north of the village of Oyster. The entire site is approximately 174
                    acres, with the landfill portion containing 78 acres. The landfill is to be used in phases and is
                    divided into four cells, each of which is expected accept waste for five years. This landfill is lined
                    and has a leachate collection system. Sampling is conducted quarterly from six shallow monitoring
                    wells and the leachate pond. Without conducting a detailed analysis, a review of the sampling
                    data revealed that the wells located downgradient from the landfill are displaying poorer water
                    quality than the background well. Monitoring of the ground water quality should continue at this
                    landfill with the consideration of the installation of wells screened deeper in the aquifer than the
                    current wells. The inclusion of these wells will help to detern-dne if any leachate is migrating in a
                    vertical direction and recharging the Yorktown-Eastover aquifer.
                    The southern landfill in Accomack County is located at Bobtown. Opened in 1973, 86 acres of its 113-
                    acre property are filled. Virginia Department of Waste Management, Solid Waste Management
                    Regulations require that any solid waste management facility for which a pern-dt was issued prior
                    to the effective date of the new regulations comply with all of the provisions of the regulations by
                    July 1, 1994. The regulations now require all landfills to be lined. The southern landfill was
                    constructed without a liner and old landfills must either be brought up to standard or be closed by
                    1992.

                    The northern landfill in Accomack County is located approximately one mile north of
                    Temperanceville. It was permitted for use in 1985 and comprises 150 acres. The landfill has been
                    divided into three adjacent, independent, fill areas and is estimated to handle approximately 22
                    tons of waste per day. At the time of construction, the projected life span of the landfill was
                    between 20 and 30 years. At this time, approximately 9 acres have been used. Should an accident
                    occur, this landfill poses a significant threat to the quality of ground water on the Eastern Shore
                    since it is located directly on the spine recharge area. Any leakage of leachate from the landfill
                    into the ground water could potentially reach the lower Yorktown-Eastover aquifer. The Northern
                    Landfill is lined, and has two components which help reduce the chance of contamination to the
                    ground water. First, there is a stormwater management system in place to catch water contributed
                    by rain. The landfill is also equipped with a leachate system which collects liquids originating in
                    the waste, all of which are stored in 10,000 gallon tanks. When the tanks fill, they are brought to
                    a wastewater treatment plant in Onancock. This landfill has fourteen monitoring wells installed to
                    collect ground water quality samples. These wells are sampled quarterly for a range of chemical
                    parameters. Currently, the samples are not showing any signs of significant contan-driation of the
                    ground water. According to the Director of Public Works for Accomack County,Joe DeMarino, there
                    have been "no problems" with any sample results from the monitoring wells (personal conversation,
                    7/24/91). Sampling should continue for both the northern landfill which is currently in operation
                    and the southern landfill which is planned to be closed. Monitoring wells with screens located
                    deeper in the aquifer should be installed to assess any vertical n-dgration of leachate to the
                    Yorktown-Eastover aquifer. The sample results are available for review in the Department of
                    Public Works office in Accornac.




                         Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                     3-15











                           Table 3-7. EPA List of Active Gen I a and Transfer Stange Disposal Facilities, Accontack and Northampton Countles

                                  IDS                        Facility Name                          L"ation            Date      Generation of Non-Acutely             Other
                                                                                                                       reported haraodaus waste kz/mo.)
                                                                                                                                 <IW       100-M > 1000
                           ACCOMACK COUNTY
                           VA9143609148       Chincoteague National Wildlife Refuge          Chincoteague              2/4/87                   X
                           VAD023812878       Davis Auto Center, Inc.                        New Church                10/28/86                 x
                           VA78000208M        GSFC/NASA Wallops Flight Facility              Wallops Island            4/7/19                   X
                           VAD044983658       Holly Famis Poultry Ind. lnc.                  Temperanceville           10/28/86                 x
                           VASNO010763        NASA Wallops Flight Center                     Wallops Island            8/15/8D                             X     I LAnd Disposal
                           VAD023864127       7Z9M-0tor Co. Inc.                             Parksley                  10/28/86                 x
                           VAD980715312       Perdue Inc.                                    Accornac                  12/29/86                 x
                           VAD982578155       VA Dept. of Transportation                     Accomac                   1/12/99                  x
                           VAD98267M4         Vaarrig-Armory-Onancock.                       Onancock                  5/14/90                  x
                           VAD988172151       Whittaker Bioproducts                          Chincoteague              7/5/90                              x

                           NORTHA@ON COUNTY                                                                                                I
                           VAD9WO9784         Alban Engine Power,                            CaR=aries                 12/279-9-           1    x
                           VA-D-982565830     Bayshore Concrete Products                     Cape Charles              1/15/88                  x
                           VA2572124483       Cape Charies Air Force Station*                Cape Charles              8/18/8D                             x
                           VAD000650531       Municipal Corp. of Cape Charles                Cape Charles              8/18/80                             x
                           VAD0237=           Center Chevorlet, Inc.                         Exmore                    11/24/86                            x
                           VAD009091620       Chesapeake Bay Bridge-Tunnel                   Wise Point                3/13/90                             x
                           VAD9881861"        Chesapeake Hardware Product%                   Chesapeake                10/2/90                  x
                           VAD051365120 Eastern Shore Railroad, Inc.                         Cape Charles              7/7/86                              x
                           IVAD988194429 Exx=Co.USA*26457                                    Exrnore                   3/28/91       X

                           * - Currently the Eastern Shore National Wildlife Refuge.
                           Sour= US EPA, Region ILI Cffice, PhiladelpW











                                      Table 3-8: Vu*nia To3dc Substances Chemical Inventory, Accomack and Northampton Counties

                                                                                               SUBSTANCE                             Anwunt Used - (0&kg/
                           Facility Name                        Latitude Longitude jAcid 15ase Organic Nutrient               120-1001101-1000 IACI-10,000110,WI-100AM >10DA001

                           ACCOMACK COUNTY
                           Harry Drarrunand, Inc.                  373325      754926                     x                   I x
                           Easter. Shore Printers                  374247      754435      X     x        x                     x
                           A j Gray & Sczi@ Inc.                   375529  7-SMM331     -X                x            x        x          x                           x
                           Helena Chenucal Co.                     3742381     754216 X                                x        x          x                           x            x
                           New Church Energy Assomates             3759001     753200                     x
                           Stony Point Decoys                      375647      753218.                    x                                x

                           NORTHANIPTONCOUNTY
                           I Bayshore Cmavft Products Corp --17-1545           7601       X#
                           I Lebanon Chennical Corp.             --f7-1606     75:W4                                                                  x                x            x

                           Source: Virginia Departv%ent of Health, Bureau of To)dc Substances










                                   Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                                                        3-16



























                                                                                                                                                                                          00,





                                                                                                                                               OCEAN
                                                                  ATLANTIC




                                                                                    J              -1 w

                                                               LANDFILL,

                                                                                                                                  IJOGGS
                                                                                                                                  LAGOON          MA13ICK
                                                   BUNDICK         NORTHEIPIN                                                                     LAGOO@I 002
                                                   LAGOON 001      LANDFILL


                                                                                                                                       =RN







                                                                                                      CHESAPEAKE





                         LANDFILL SITE

                         SEPTAGE LAGOON SITE
                                                                                                                                                                                                               L









                           0            22,000 33.000
                            scale I loot)



                                                                                                                                3-17














                  SEYrAGE DISPOSAL

                  There are three anaerobic septage lagoons located in the two counties which are owned by two
                  well-drilling companies (Figure 3-5). The lagoons are in wooded areas which are set aside as
                  receptacles for septage. When septic tanks are periodically emptied, the waste gets dumped into
                  these lagoons. Lagoons are usually earth-diked ponds, varying in shape and size, and are
                  relatively maintenance-free. The entire lagoon stabilizes biodegradable organics under anaerobic
                  conditions where the rate of reaction or stabilization is slow. Bad odors are a characteristic of
                  these areas, and lagoons can threaten the ground water quality because they contain concentrations
                  of organisms close to that of primary waste water sludge.

                  One of the companies which owns the lagoon estimates that their lagoon receives waste from 1,000
                  septic tanks a year. The other reports that its two lagoons combined receive an average of 75,000
                  gallons of septage per month. According to the Northampton County Ordinance, septic tanks must
                  be emptied every five years. This follows the recommendation of the Chesapeake Bay
                  Preservation Act. As yet, Accomack has not adopted this as policy and has no set standard for
                  emptying-intervals of septic tanks. Undoubtedly with the enforcement of the Preservation Act,
                  these lagoons will be used more heavily.

                  In Virginia, septage was essentially unregulated prior to 1982. Now septage is subject to on-site
                  sewage handling and disposal regulations requiring pumpers to take septage to approved facilities.
                  Such facilities are municipal treatment plants or state-approved lagoons, which are aerobically
                  digested by bacteria. In counties with population densities of less than 100 persons per square mile,
                  septage can be directly applied to the land with the approval of several boards (Weigmann and
                  Kroehler, 1988). The Eastern Shore lagoons are not required to follow the 1982 legislation because
                  of a grandfather clause. The lagoons are not lined, and thus pose a threat to the ground water
                  supply. In particular, one of the lagoons in Accomack County lies within the spine recharge area.
                  As with the landfill, the location of this lagoon in this special area poses a serious threat to ground
                  water quality as deep as the lower confined aquifer. No contamination has been documented to
                  date, and it is speculated that sediments have lined the bottom of the lagoon (J. Green, personal
                  communication, 1991).

                  Review of ground water samples taken in 1985 from two monitoring wells located at the private
                  lagoons in Accomack County revealed that as of that time there was no impact on ground water
                  quality from these lagoons. In order to be assured that water quality beneath the site is not
                  impacted, ground water quality monitoring should continue, and the sampling should include
                  analysis for organic compounds. In addition, the ground water flow direction should be determined
                  to ensure that the wells are indeed capturing recharge from the lagoons.














                       Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                 3-18



                                                                              I
                                                                              I
                                                                              I
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                                                                              I
                                                         EXISTING LAND USE
                                                                         4    1
                                                                              1
                                                                              1
                                                                              1
                                                                              I
                                                                              I
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                                                                              I
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                  SECTION 4 - EXISTING LAND USE


                  PURPOSE

                  The purpose of this section of the report is to appraise the existing land use conditions on the
                  Eastern Shore of Virginia and to analyze the ways which land use distribution, controls, and other
                  factors may have an overall effect on ground water. The use and good condition of the ground water
                  supply is critical for the continued viability of human habitation in the region since ground water is
                  the only source of potable water. In the buildout and nitrogen loading portion of this study,
                  scenarios for assessing the impacts of land use development on ground water are explored. In
                  conjunction, land use instruments which govern the development within the spine recharge area and
                  wellhead protection areas must also be analyzed.


                  OVERALL STATUS OF LAND USE CONTROLS

                  Currently, both Accomack and Northampton Counties have recently revised their comprehensive
                  land use plans (Accomack in 1989, Northampton in 1990). Each county also has a zoning ordinance,
                  both of which are under revision. In this report, the comprehensive plans are the primary sources
                  for general information on existing land use. Separate from the county bylaws, there are town plans
                  and zoning ordinances for 12 incorporated towns in the region-8 in Accomack and 4 in Northampton.
                  Two other towns, one in each county, have zoning ordinances, but no plan. Eight of these towns also
                  have subdivision ordinances. Since the percent of overall land area of the region they affect is
                  relatively small, they are not exan-dned separately here.

                  Each county's comprehensive plan is designed to set development policy only, as they do not have
                  legally enforceable land use maps. The Accomack Plan states that, "adoption of the
                  Comprehensive Plan is only the beginning of the planning process. To derive any benefit from the
                  plan, steps must be taken toward its implementation. The principal instruments of plan
                  implementation are the zoning and subdivision ordinances, and sufficient staffing of the Accomack
                  County Department of Environmental Affairs to effectively administer these ordinances"
                  (Accomack County Comprehensive Plan, 1989, p. i4).

                  The Northampton plan states that the "phase of the Comprehensive Plan that addresses private
                  sector issues is the land use plan, together with the regulatory ordinances and policies adopted by
                  local government. The Land Use Plan is the umbrella document that sets the pattern and provides
                  overall guidance" (Northampton County Comprehensive Plan, 1990, p. 11-9). The Northampton
                  Plan further states that it "presents a Land Use Plan for Northampton County. The Plan has been
                  prepared in coordination with updated land development regulations to address issues with which
                  the county is faced in the late 1980's and which will likely continue during the 1990's.
                  Northampton County is currently considering significant changes to its existing zoning ordinance.
                  The advisory nature of both county plans presents a conservative approach to the interpretation of
                  Virginia Law in defining the purpose of the Comprehensive Plan and Land Use Plan. In
                  comparison, the counties of Fairfax and Loudoun, which are facing substantial issues of growth
                  including traffic and transportation problems and a severe strain on county public facilities, have
                  developed comprehensive plans (particularly the land use plan and map) that are enforceable
                  legal documents which can supersede zoning and other development regulations in many cases. In
                  these Northern Virginia cases, the long-range impacts of future county development have been
                  assessed according to plan projections of population, employment, land-use density and other factors
                  to assess future county service and facility needs, funding requirements, and needed changes in other
                  county regulatory instruments.


                    Ground Water Supply Protection and Manage?nent Plan for the Eastern Shore of Virginia
                                                              4-1







                    Because Eastern Shore of Virginia Plans are primarily to be carried out through the zoning and
                    related ordinances, such as subdivision, these ordinances will be the primary focus of this section.

                    There are other factors that affect existing land use development on the Eastern Shore. These
                    include regulations for wells, septic systems, forestry, agriculture, mining, and stream and shore
                    bank protection. While such regulations have been in effect for varying periods of time and have
                    been enforced to varying degrees, many regulations are fairly recent and their effects thus far on the
                    long-term development of existing land use is thought to be relatively slight. Therefore it is only
                    necessary to assess these regulations in terms of their effects in the future. In addition, the recently
                    enacted Chesapeake Bay Preservation Act is a comprehensive and potentially far-reaching
                    instrument that can have substantial effects on future land use. Both counties have guidelines in
                    place to comply with the Act. Potential effects of the Act on ground water are examined at the end
                    of this chapter.


                    EMSTING PATTERNS OF LAND USE
                    Agricultural land under irrigation, residential land in subdivisions, and industrial land occupied by
                    industries that are intensive water users are the most significant factors of existing land use
                    patterns that influence ground water withdrawal on the Eastern Shore. All of these factors will be
                    exan-dned in the context of existing land use in the region.
                    Table 4-1 summarizes the existing distribution of land in broad categories within the region. The
                    categories of land use as defined in the Accomack and Northampton Plans do not completely
                    coincide, but they are close enough that a broad land use profile of the region can be assembled. The
                    table illuminates several contrasts between the two counties:

                            1 )      nearly 57% of all land in the region lies in Accomack County;
                            2)       nearly 70% of all land in agriculture and forestry uses is located in Accomack;
                            3)       nearly 66% of all land in marshes, wetlands and tidal areas is located in
                                     Northampton;
                            4)       nearly 78% of all residential land lies in Accomack;
                            5)       over 96% of all industrial land lies in Accomack.
                    Thus, the overall picture of land use in the region is one of more intense development in Accomack
                    County, even in the land use categories often viewed as land extensive such as agriculture and
                    woodlands. Agricultural, residential, and industrial uses could have potentially significant affects
                    for ground water consumption in Accomack County. Within Northampton County, agricultural and
                    residential uses are worth a closer look.














                        Ground Water Supply Protection and Managetnent Plan for the Eastern Shore of Virginia
                                                                    4-2









                                         Table 4-1: Existing Land Use - Accomack and Northampton


                        Category        Northampton             %       Accomack          %          Total            %
                                            (Acres)                        (Acres)                   (Acres)
                        Agriculture &       87,025             37.8        198,879        65.3       285,904          53.2
                         Woodlands
                        Residential          3,800              1.6         13,361        4.4          17,161         3.2
                        Commercial            123               0.1            407        0.1             530         0.1
                        Industrial            102               0.1          2,454        0.8          2,556          0.5
                        Institutional         715               0.3            840        0.3          4,111          0.8
                        Recreation            177               0.1          8,332        2.7          8,509          1.6
                        Marsh/Tidal        135,500             58.9         70,371        23.1       205,871          38.3
                        Other*               2,505              1.1          9,996        3.3          12,501         2.3

                        TOTAL              229,947            100.0        304,640       100.0       537,143        100.0

                        *In Northampton, roads and utilities are included; in Accomack, figure includes land identified
                        as vacant, but not roads and utilities. Vacant land is not identified in Northampton.

                        Source: Northampton and Accomack Comprehensive Plans (1990,1989)


                   LAND USE AND OPEN SPACE REQUIREMENTS FOR WATER AND SEWER

                   There are three general conditions under which drinking water and waste water can be provided on
                   a building lot. In some cases there are central or "public" systems for water and sewer, including a
                   central or common septic field for sewage disposal. In others, a central water system is available,
                   but individual sewerage, usually a septic system, must be located on each lot. The third case is the
                   most common on the Eastern Shore of Virginia, where both individual water from a well and
                   individual sewerage are provided on each lot.

                   An individual septic system, including a holding tank and drain field, can occupy about 5,000 square
                   feet when sized for a three or four bedroom, two bath house. Setback distances are required for
                   wells from building foundations and from the septic system, and this adds another several thousand
                   square feet. Current subdivision regulations in Northampton require, and the Accomack
                   Comprehensive Plan recommends, that space be available on each lot for a reserve drainfield. This
                   adds another requirement for unobstructed open space, perhaps another 4,000 square feet.

                   Land above septic systems cannot be used for other purposes such as plantings (excluding grass),
                   walkways, driveways, parking areas, or any other use that would possibly result in the blockage
                   of, or damage to, the system. Additionally, "protection areas" around wellheads are now being set
                   up to help assure that contan-dnants will not penetrate the well and seep into the ground water
                   below.


                   When the requirements for wellhead protection, primary septic system and backup drainfield are
                   taken together, there may be a need for upwards of 11,000 square feet on each lot devoted to these
                   systems. A septic system and backup drainfield, when used in conjunction with a central water
                   system, may still require 8 to 9,000 square feet or more. These figures should be kept in n-dnd when
                   developable land in the two counties are examined in the following pages.




                       Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                    4-3










                    EMSTING LAND USE IN ACCOMACK COUNTY

                    Tables 4-2 and 4-3 summarize existing zoning controls in both Eastern Shore counties.

                    Agriculture and Agricultural Districts
                    Agriculture in Accomack County accounts for over 65% of all land use. Potential problems exist for
                    ground water conditions in such areas from the improper application of pesticides and fertilizers,
                    inadequate handling of animal wastes, poor methods of retaining soils, and other land-based
                    conditions that can affect ground water through runoff of, or percolation from, surface water to
                    ground water recharge areas.
                    There are several conditions in the Accomack agricultural areas (A-districts) that are noteworthy.
                    First, large amounts of such land under active crop production are irrigated. Improper irrigation
                    accelerates the removal of soils, pesticides, fertilizers, and other matter from irrigated land. Some
                    of the chemicals may remain dissolved in water and percolate through to the ground water.
                    Second, the minimum lot requirement under Accomack zoning and subdivision regulations is 30,000
                    square feet per lot (Table 4-3). While only single fan-dly residences are pern-titted as a matter of
                    right in the A-districts, there are no discernable restrictions on subdivisions. Thus, subdivision of
                    land in agricultural districts into 30,000 square foot lots, is possible. Under current zoning
                    regulations, up to 46 percent or 13,800 square feet of each lot can be covered by a primary structure.
                    There are no lin-dtations on coverage of secondary or auxiliary structures except those established
                    by setback requirements. Such structures could easily add another 3-4,000 square feet of impervious
                    surface. The remaining 11-12,000 square feet of open area may be adequate for a well and septic
                    system, but the relatively small lot size and possibility of substantial numbers of such lots close
                    together raises the possibility of deleterious effects on the ground water.
                    A third land condition in agricultural districts is the frequent juxtaposition of agricultural and
                    forestry uses with areas which often have direct relationships with ground water sources. These
                    areas can include bogs or marshy areas; exposed, sloping banks; streams or other water bodies;
                    wellhead areas; natural springs; pits used for dry waste or garbage disposal; and septage lagoons.

                    Housing and Residential Districts
                    Residential uses account for slightly less than 4.5% of land uses in Accomack County, but they
                    account for over 13,000 acres of land area. Currently, conditions in residential areas (R-districts)
                    that could adversely affect ground water include potentially high subdivision densities, lack of
                    sufficient space on each lot for proper wastewater disposal, and high densities of multi-fan-dly
                    buildings on relatively small lots.
                    There are at least three densities of single fan-dly usage permitted in the R-District. As seen in
                    Table 4-3 if a lot has central water and either public or private sewer, the lot area requirement is
                    10,000 square feet. If the lot has either central water or central sewer, but not both, the lot size must
                    be increased to at least 15,000 square feet. If the lot must accommodate both its own water and
                    sewer systems, then it cannot be less than 20,000 square feet in size. Setback requirements mean that
                    about 60 to 70 percent of these lots that are 10,000-12,000 square feet may not be occupied by the
                    primary structure. However, ancillary structures, driveways and other features often found in
                    residential areas, such as walks, trees, and other landscaping, can cut down the amount of open
                    space available for well and septic areas. Thus, as lot size increases substantially to accommodate
                    individual water and sewer systems, the amount of space usable to such systems may only increase
                    marginally, if at all, and the percentage of such space relative to lot size actually decreases.


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                                                                 Table 4-2. Imul Use Category by Zoning District, Easkm:n Short of Virginia

                           Use Categorv                          Districts

                                                                 Actitimack                               Northampton
                                                                 A    R      B       I     BI             AR R20 R11 RM MHP CN CC                         CW PI         IL
                           Ag./Forestry                          x    a      a             e              xe    xe                                               x
                           Preserve                              x    a      a             x              x     x                                                x
                           Lodge/Club                            x    a      x                            x     x             e                           x
                           Rec./Private                          x    e      a                            x             0     e      xe            x      x
                           Rec./Public                           a    x      a                            x             a            xe            x      x
                           Dock, Private                         x    a      a                            x                                               x
                           Dodr, Public                          a    a      a                            x                                               x


                           Single Family                         x    x      a                            x     x       x     x
                           Multi-Fan-Lily                        a    e      a                            x     x       x     x      x      x      x      xe
                           Mobile Home                           e    e      e                            xe    xe      xe           x
                           Mobile Home Park                      e    a      a                                                       x
                           Camp/Trailer                          e    e      a                            e                                               x
                           less. Housing                         a    a      a             x              x

                           Home Office                           x    x      a                            x     x       x     x
                           School Library                        x    x      x                            a     a       x     e             x      x             x
                           Religious                             x    x      x                            x     x       x     x      x
                           Cemetery                              x    a      a                            a
                           Post Office                           x    x      x                                  e       x            e                    x
                           Other Public                          a    a      a                            e     e       x     e      e                    x      x


                                                                 x    x      a       x                    x     xe      xe    xe     xe     xe     x      xe     x      x
                           Retail Gen.                           e    e      x                                                              x      x      x
                           Public Assem.                         a    a      x                                                              x      x
                           U,ili,y



                           Restaurant                            e    a      x                            e                                 x      x      x
                           Hotel/ Motel/Transient                e    e      x                            e     e                                  x      x


                           Industry General                      e    a      e       x                                                             e      e      x      x
                           Ag. Processing                        a    a      e       x
                           Seafood Plant                         e    e      e       x                    e                                               e
                           Sawmill                               a    a      e       x                                                                           x
                           Quarrying /Conc.                      a    a      a       x                                                                           x
                           Marine Comm.                          e    e      x       x                    x                                               x      x
                           Serv. Sta./Gar.                       a    a      x       x                                                      e      x
                           Dry Ceaning/Laundry                   e    e      x       x                                                      x      x
                           Build. Supply                         a    a      x       x                                                                                  x
                           Indoor Stor.                          a    a      a       x
                           Printing/Mach.                        e    e      x                                          e                   x      x             x
                           Office, General                       0    e      x                                                e             x      x             x
                           Hospital                              e    e      x                                                e                           xe
                           Other Health                          a    e      x                                                e                    xe                   x
                           Funeral Home                          a    a      x                                  e       e                   e      x
                           Junkyard                              a    a      a                                                                     e
                           Other Outdoor 1,or.                   a    a      a       x                                                                                  x
                           Airport                               a    a      a                            e                                                             x
                           Outdoor Adv.                          a    a      a                            x     x       x     x      x      x      x             x      x
                           Other Trans.                          a    a      a       e                                                      x      xe            x      x
                           Landfill                              a    a      a                            a



                           a - any other use, review needed, e     exception, review needed, x     permitted, xe    permitted in some areas review needed in others.










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                                      Table 4-3: Zoning Lot Sizes and Open Spam Accomack and Norflumpton Counties

                                                                        Minitnurn         Dimensions                Gross
                                          Zone District                    Lot Size      Min. Lot Size        Open Space*           Percent
                                            By County                      Sq. Ft.          in Feet                 Sq. Ft.       Open Space

                               ACCOMACX

                               * - Agriculture                             30,000           150 x 2DO               16,200             54.00
                               * - Residential
                                   Central Water/Sewer                     10,000           100 X 100               8,950              89.5
                                   Cent. Water/Indiv. Sewer                15,000           100 X 150               10,450             69.7
                                   Indiv. Water/Sewer                      20,000           100 x 200               11,950             59.7
                               Multi-Family
                                   Central Water/Sewer
                                   Number of Units
                               2                                           12,000           100 x 120               9,550              79.6
                               3                                           14,000           100 x 140               10,150             72.5
                               4                                           15,000           100 x 150               10,450             69.7
                               5                                           16,000           100 x 160               15,750             67.2
                               20                                          31,000           100 x 310               15,750             50.8
                               B - Business                                NA                  NA                   NA                 N A
                               I - Industrial                              NA                  NA                   NA                 NA
                               BI - Barrier Island                         174,240          200 x 871               84,460             48.5



                               NORTHAMPTON

                               AR - Ag. Residential                        43,W             125 x 348               26,400             60.6
                               Residential
                                   R-20 Single Family                      20,000           80 x 250                12,250             61.3
                                   R-1 1 Single Farrifly
                                     Public Water/Sewer                    11,000           60 x 183                5,860              53.3
                                     Public Water or Sewer                 20,000           60 x 333                8,860              44.3
                               RM - Multi-Family
                                   Duplex: Public Water/Sewer              40,000           110 x 363               10,498             52.5
                                     Indiv. Water & Sewer                  50,000           110x227                 11,568             46.3
                                   Patio/Atrium                            100,000          880 x 113               26,400             26.4
                                   Townhouse                               40,000           346 x 101               19,800             49.5
                                   Multi-family, Other                     25,000           140 x 179               15,250               61
                               MI-T - Mobile Home Park                     5,000            40 x 125                4,000                80
                               CN - Commercial Neighborhood                15,000           100 x 150               6,840              45.6
                               CG - Commercial General                     15,000           100 x 150               6,840              45.6
                               CW - Commercial Waterfront                  15,000           100 x 150               4,500                30
                               PI - Planned Industrial                     50 acres        1000 x 2178          1,506,800              69.2
                               IL - Industrial Limited                     435W             200 x 218               27,960             64.2
                               IG - Industrial General                     30000            150 x 200               21,070             70.2
                               HD - Historic District                      NA                  NA                   NA                 N A
                               AP - Airport Protection                     NA                  NA                   N A                NA
                               PUD - Planned Unit Develop.                 NA                  NA                   NA                 NA
                               FH - Flood Hazard                           NA                  NA                   NA                 NA

                               *This figure represents the minimum open space per lot or development possible under existing yard
                               requirements. Driveways, walks, accessory uses and other site features could further reduce this area.
                               Conversely, not all buildings am built to these setback lines.


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                  Potentially inadequate space for water and sewer systems is also found in R-Districts where multi-
                  family structures are allowed. Table 4-3 indicates that while two-fan-dly structures require at
                  least 6,000 square feet each per lot, the construction of a five-fan-dly structure would effectively
                  double the unit density. If a twenty-unit structure were constructed, the density would be doubled
                  again, and the potential effects on ground water more pronounced. A two-unit structure would have
                  a possible 9,550 square feet of open space for water and sewer systems. Three or more units would
                  increase this acreage only marginally. The amount of open space per unit would actually decrease
                  as would the percentage of such space relative to the size of lot. As with the single-fan-dly
                  examples, other features could further reduce the space available.

                  One anomaly present in the Accomack Subdivision Regulations is found in Section 5., Paragraphs
                  5.2.4-1 through 5.2.4-3. These paragraphs repeat the requirements of varying lot sizes found in the
                  R-District. (Table 4-3). However, uniformly larger lots (15,000 square feet) are required if the area
                  has gj1hff public water or public sewer. This seems to make sense in the case of central water and
                  individual sewer (septic or septage) because of increased land requirements for the sewage system.
                  However, the reverse situation would not seem to require additional lot size. Individual wells may
                  require somewhat more area due to well location requirements, but not as much as individual
                  sewerage.

                  Industry, Business and Industrial/Commercial Districts

                  Industry and commercial uses occupy less than one percent of the land in Accomack County.
                  However, estimates of water consumption by some of the major water users in Accomack suggest that
                  industry uses in excess of 30 percent of the ground water on a daily basis (Comprehensive Plan, 1989,
                  p. 11-68). There is no minimum lot size in either industrial or commercial districts. While facilities
                  with individual sewage disposal systems must have their lot sizes approved by the state health
                  official for the county, the criteria for such approval are not clear in the Zoning Regulations. Thus,
                  uses on one site could substantially affect uses on an adjacent site.


                  EXISTING LAND USE IN NORTHAWTON COUNTY

                  Table 4-3 also summarizes existing open space due to zoning controls in Northampton County.

                  Agriculture and Agricultural Districts

                  Agriculture and woodlands in Northampton account for almost 38 percent of all land use. Similar
                  potential problems are associated with agriculture in Northampton County as with Accomack
                  County. Ground water contamination may result from the activities of pesticide and fertilizer
                  applications, problems with soil erosion from improper tillage or forestry harvesting, and leaking
                  septic or cesspool facilities. As in Accomack County, large portions of agricultural land in
                  Northampton are irrigated, and it is estimated that 19-23 percent of all agricultural land in
                  Northampton is currently under irrigation.

                  Residential zones in Northampton agricultural areas offer larger n-dnimum open space potentials
                  than those in Accomack. The minimum lot size for residential development in Northampton
                  agricultural districts (AR) is one acre (Table 4-3). Using minimum frontage and setback
                  requirements, it may be ascertained that 26,400 square feet of each one acre lot not fronting on water
                  or Route 13 would be available for open space. This compares to a figure of 16,200 square feet in the
                  A Districts of Accomack. As in Accomack, this open space may be covered by outbuildings, walks,
                  driveways, or other features that further restrict the space used for wells or septic systems. Again,



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                    the result of these relatively small areas introduces the potential for forcing wells and sewerage to
                    co-exist in somewhat restricted areas.

                    The land use categories that cover the largest portion of Northampton are marsh/tidal areas;
                    these occupy almost 59 percent of the county, over 135,000 acres. Agriculture and woodlands take up
                    about 38 percent. Inevitably these two uses are intertwined in many parts of the county, in that
                    water from wetland areas associated with dammed creeks may be used for irrigation purposes, and
                    crops may have been planted within drained marsh areas. Where this happens there is the
                    potential for direct contamination of ground water by agricultural or forestry practices.

                    Housing and Residential Districts
                    Residential land use in Northampton occupies a much smaller land area in Northampton than in
                    Accomack-3,800 acres versus 13,361 acres respectively. Residential zoning in Northampton,
                    however, is somewhat more diverse than in Accomack. While the single residential district used
                    in Accomack can accommodate single family and multifan-dly housing in several configurations, the
                    Northampton R Districts are more detailed in the number and type of housing units permitted and
                    the conditions under which such units are permitted given types of water and sewer systems.
                    More importantly for ground water protection, Northampton single family districts often require
                    larger lots for single family houses for either central, combined or individual water/sewer systems.
                    For example, central water and individual sewer in Northampton require a lot size of 20,000 square
                    feet. In Accomack, the corresponding lot size would be 15,000 square feet. However, in
                    Northampton County the primary building coverage can occupy nearly 66 percent of the lot, leaving
                    only 8,860 square feet or less for a well and sewer system. In Accomack, the building coverage is
                    restricted to about 30 percent, leaving over 10,400 square feet for landscaping, well, and sewer space.
                    Current zoning in Northampton County provides for a Residential Multi-family or "RM" District.
                    Duplex, patio/atrium, townhouse and apartment structures are permitted in this district. Of these,
                    the patio/atrium option can occupy at least 73 percent of the lot area, based on a configuration
                    incorporating a n-dnimum of 10 dwelling units. The remaining 2,640 square feet per unit would be
                    very crowded should individual septic systems be installed. Additional landscape features such as
                    driveways, parking areas and plantings would further reduce the space for septic systems. It is
                    typical that this type of unit is built to the lot line on at least two sides, and thus the close
                    proxin-dty of individual septic systems is almost guaranteed.
                    Given the current zoning, townhouse units have the potential to be even more crowded than the
                    multi-family residential units. Individual units could have just slightly over 1,500 square feet for
                    septic systems, and multifan-dly apartment units can have about 3,200 square feet of open space per
                    unit. These units can also be in tight configurations raising some of the same concerns expressed
                    about the atrium units. At least 10 parking spaces must be provided for the n-dnimum 5 units, which
                    would occupy about 560 feet per unit. Thus the space available for septic systems would be reduced
                    to about 2,600 square feet per unit. Additional landscape features could reduce this figure even
                    further.

                    Industry, Business and Industrial/Commercial Districts
                    Industrial and commercial uses occupy about 225 acres or less than one-fifth of one percent of all
                    land in the county. While such minimal areas are not likely to have major impacts on ground water
                    supplies, several features of the zoning requirements for such areas are worth noting. For example,
                    in any commercial district, CN, CG, or CW, the building and parking spaces can occupy over 50
                    percent of any development parcel. The amount of open space left for the well and septic system-


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                  6,800 square feet in the configuration adopted for the assumption used here-may be minimal given
                  other features, such as trash disposal, landscaping and parking and circulation, that can occupy the
                  site. In the CW or Commercial Waterfront District, there are no open areas required, thus allowing
                  for a particularly crowded water and sewage system for those sites adjacent to water bodies.

                  Other Uses

                  Northampton has a Planned Unit Development District in which 75 percent of the land area may
                  be occupied by lots, buildings, streets and off-street parking. If such lots were developed as
                  townhouse or atrium developments, then on-lot space for septic systems would be extremely limited.
                  The 150 units or lots that would be permitted under the minimum development size of 15 acres and
                  the maximum density of 10 dwelling units per acre for RM zoning could result in a substantial
                  demand for a central, land based sewage disposal system. Of the 25 percent of the development left
                  in open space, about 3.75 acres, much or most could be occupied by such a system.
                  By far the largest land use in Northampton County is that occupied by marsh or tidal areas.
                  However, there is no specific zone district to treat such land. The Northampton Comprehensive
                  Plan addresses the need for special treatment of tidal wetlands, barrier islands, and wetlands
                  bordering on Bay side creeks and their branches. Additionally, in the Zoning Regulations, the use
                  of wetlands in calculating developable areas on development parcels is excluded. However, there
                  appears to be no specific protection plan for non-tidal wetlands, which are important for the
                  recharge of ground water supplies.

                  Table 4-2 sets out detailed use categories and establishes their status in each zoning district for the
                  two counties. In general, Accomack County appears to have a less restrictive, more inclusive
                  ordinance. As evident in the table, nearly every land use is either permitted or excepted in
                  agricultural, residential, and business districts. Comparatively, industrial zoning is highly
                  restrictive, allowing only industrial and utility uses, with no exceptions allowed for other non-
                  residential or residential uses.

                  Northampton's approach to zoning is quite the opposite. The county has an agricultural district,
                  four residential districts, three business or commercial districts, and three industrial districts.
                  Northampton also has four "overlay zones": historic, airport protection, planned unit
                  development, and flood hazard, which can be used with the plan review to modify the underlying
                  zones for the purposes of each overlay. In addition, Northampton has further front yard setbacks
                  required in its Zoning Regulations along U.S. Route 13 that would increase the area space per lot.
                  This is designated as "Highway Protection" in the Comprehensive Plan.

                  Northampton's zoning is substantially restrictive. For example, some agricultural uses are
                  permitted only with special exceptions in the Agricultural /Residential District. Few industrial
                  uses, even sawmills and agricultural processing plants, are permitted in the
                  Agriculture/ Residential District. In residential districts, many public facilities are either
                  prohibited or only permitted with a special exception. Some anomalies do exist. For example, in
                  the Residential Multi-family District, usually the least restrictive of any residential zone, only
                  religious uses are permitted as a matter of right. Schools, libraries and some other public facilities
                  are permitted only with special exceptions. Post offices are prohibited, as they are in AR Districts.







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                     LAND USE CONTROLS AND EFFECTS ON GROUND WATER
                     The following chart summarizes land uses, the categories that may have particularly substantial
                     effects on ground water, the general nature of those effects, and the status of those land use
                     categories under present zoning or other review.
                                      Table 4-4: Analysis of Land Use Effects on Ground Water Supplies


                         LAND USE/              NATURE OF GROUND-                                 REVIEW
                         USECATEGORY            WATER EFFECT                                      STATUS

                         AUiculture
                         Cropping               Pesticides, fertilizers may penetrate             Matter of right (MOR)
                                                to water table and ground water                   in both counties.*
                                                                                                  (see last page of table)
                                                Irrigation draws substantial amounts of           Most withdrawals
                                                water in dry periods.                             are not metered.
                         Grazing                Animal wastes may contaminate water               Review under Nor-
                                                table and ground water.                           thampton Zoning only*.
                         Forestry               Pesticides may penetrate to ground water;         Matter of right (MOR) in
                                                cutting may enhance erosion.                      both counties.


                         Residential
                         Single Family          Some lots may be too small to comfortably         Matter of right, but
                                                accommodate wells and/or septic systems,          VA health review is
                                                and drainfield reserve areas.                     required.

                         Mobile Homes           Mobile Home Parks must have enough                Special exception or
                                                land per unit to accommodate well and/or          health depart review;
                                                septic system.                                    both counties.
                         Multi-Family           As for single family.                             Matter of right, but
                                                                                                  VA health review is
                                                                                                  required.
                         Utility                This category can include public and              Matter of right in
                                                private water and sewage operators that           Accomack A, R and
                                                can withdraw large amounts of water and           I zones. Review in B zone.
                                                dispose of large amounts of waste water.          MOR in Northampton
                                                The methods, condition of equipment, and          AR, CG, PI and IL
                                                conservation practices of the operator can        zones. Possible review
                                                affect ground water supplies.                     in others. VA Water
                                                                                                  Control Board requires
                                                                                                  permit for large
                                                                                                  withdrawals, discharges.




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                               Table 4-4. Analysis of Land Use Effects on Ground Water Supplies (Continued)

                        Retail
                        Restaurant              Restaurants can be large water users and           Accomack - reviewed in
                                                often, discharge substantial amounts of            A,R zones. MOR in B.
                                                waste water.                                       Northampton - MOR in
                                                                                                   C zones. Reviewed by
                                                                                                   VA Board of Health
                                                                                                   for minimum water
                                                                                                   flow.

                        Hotel, Motel,           Can be large water user and waste water            Accomack - reviewed in
                        Other Transient         discharger. Especially in combination              A, R zones. MOR in B.
                        Facilities              with a restaurant.                                 Northampton -
                                                                                                   reviewed in AR, R20
                                                                                                   zones. MOR in CG, CW.
                        Indusfty
                        General                 A variety of industries including research         Accomack - MOR in
                        Industry                labs, production facilities, and service           I zone; Reviewed in A,
                                                industries-especially food and bottling            Rand B zones. Nor-
                                                industries--can be major water users and           thampton - MOR in PI, IL
                                                can discharge toxic wastes, depending on           and IG zones. Excep-
                                                their processes.                                   tion in CG and CW
                                                                                                   zones. Major water
                                                                                                   withdrawals subject to
                                                                                                   VA State Water Con-
                                                                                                   trol Board approval.

                        Ag. Processing,         These industries usually use large amounts         Accomack - See above.
                        Seafood Plant           of water for cleaning the product and              Northampton - Excep-
                                                usually discharge waste water filled with          tion in IG for Ag.: in
                                                food wastes.                                       CW, IG for seafood.

                        Sawmill, Quarry-        Sawmills may use water for cooling and             Accomack - MOR in
                        ing, Concrete Mix       discharge waste pulp; quarries sometimes           L Exception in A, R,
                                                act as "drain holes" for surrounding area          B. Northampton - Saw-
                                                contaminants; concrete plants use sub-             mill MOR in IG;
                                                stantial water and discharge waste filled          Quarry, Conc. MOR in
                                                with lime and toxics.                              P1. Exception in IG.

                        Marine Commer.,         These uses often discharge or leak petro-          Accomack - Marine
                        Service Station,        leum products to the ground. Additionally,         Serv. Stn. MOR in B,I.
                        Airport, Junk yard      battery acid and other by-products may             Airport, junk yard
                                                leak from junk yards.                              exception in A,R, B Nor-
                                                                                                   thampton. Marine
                                                                                                   MOR in AR, CW, PI
                                                                                                   and IG. Serv. Stn. MOR
                                                                                                   in CG, Junk yard MOR
                                                                                                   in IG exception in CG;
                                                                                                   Airport MOR in IG,
                                                                                                   exception in AR.



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                               Table 4-4: Analysis of Land Use Effects on Ground Water Supplies (Continued)
                        Dry Cleaning,          These uses can discharge distillates and        Accomack - Dry Clean
                        Building Sup.          and other toxics to land areas.                 Bldg. Supply Exception in
                        Other Storage                                                          A, R; Other Stor. MOR in
                                                                                               1, Exception in A, R, B.
                                                                                               Northampton - Dry
                                                                                               Clean MOR in CN, CG;
                                                                                               Bldg. Supply MOR in IL.
                                                                                               Indoor Stor. MOR in IG;
                                                                                               Outdoor Stor. MOR in IL,
                                                                                               IG.

                        Landfill               Landfills have been shown to be potent-         Accomack - Exception
                                               ially major polluters of ground water sources.  only in A, R and B
                                               Substantial amounts of toxic materials          zones. Northampton
                                               have been-and are-dumped in these               Evidently pro-
                                               locations and, depending on ground soil         hibited in all zones.
                                               and geology, may leach these toxics to
                                               aquifer.

                        *Farm Use Only


                    Generally, where the above uses are a matter of right, that is, where they can proceed to
                    construction without review by government authorities and other advisers qualified to assess their
                    effects on soil and ground water conditions, they may pose a distinct threat to ground water
                    supplies. Degradation can occur either from overuse or contamination of ground water aquifers, in
                    areas where soil and geological conditions indicate a high susceptibility. In cases where
                    potentially harmful uses are reviewed, the review process may need strengthening to assure that
                    such reviews are accomplished beyond that of the normal site plan or other process. After the
                    review and possibly the remediation, the uses which could have highly adverse long and short-
                    term effects should be monitored on a periodic basis to be sure that the remediation remains in
                    place. A field survey and engineering /planning studies should be conducted to determine what
                    existing land uses are potentially threatening to ground water and soil conditions so that remedial
                    measures may be carried out.


                    SUBDIVISION OF LAND

                    Both counties have subdivision ordinances in place. In Accomack, final plats must be approved by
                    the county and State Highway Department for public streets and drainage, and by the State
                    Health Department for water and sewer facilities. Health and public road improvements must be
                    secured by cash or a bond. In addition, trailer parks must also be approved by the State Bureau of
                    Tourism. Accomack's subdivision ordinances also states that the State Health Department can
                    order lot sizes larger than the n-dnimum sizes established in the Zoning and Subdivision Ordinances
                    if "factors of drainage, soil condition, population density or other conditions can cause potential
                    health problems." Additional open space requirements are set out in the ordinance for buffering
                    trailer parks from surrounding property. Lots larger than 3 acres in size are excluded from
                    subdivision requirements under the Subdivision Ordinance in Accomack County. All final
                    subdivision plats must be prepared by a state-registered engineer or surveyor. There is currently no



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                   requirement for drainfields reserved for septic systems in Accomack, although that is suggested in
                   the County Comprehensive plan.

                   In Northampton, divisions of land are apparently excluded from subdivision review if the resultant
                   lots are 5 acres or greater in size and if a single subdivision of a lot or parcel is made for the purpose
                   of sale or gift to a member of the immediate family of the property owner. If the subdivision has 26
                   or more lots created, it is considered a major subdivision. A major subdivision must be reviewed by
                   the State Highway Department, the State Health Officer, each incorporated town within 2 miles
                   of the project, each utility company providing service to the project, and all abutting property
                   owners and other agencies the Planning Director deems appropriate. The State Highway and
                   Health Department comments must be received prior to review and action by the County Planning
                   Commission. Plans must be prepared by a state-licensed surveyor or engineer. All major
                   subdivisions must have a central water system in Northampton. All proposed improvements are
                   bonded for implementation by the owner or his/her agent.

                   The procedure for approval of minor subdivisions, those with 25 lots or less and with lot areas of
                   less than five acres, is the same as that of major subdivisions except that final approval can be
                   granted by the Planning Director rather than the Planning Commission.

                   Lots in Northampton that use private, individual wells and septic systems must provide an
                   additional, non-overlapping replacement drainfield site. No such site is required if a well is not
                   located on the lot. Additionally, wetlands cannot be separated from a lot. All wetlands must be
                   incorporated into an adjoining lot where they are counted against the lot size for purposes of
                   establishing n-dnimum lot area and for calculating buildable portions of the lot. This can have the
                   effect of allowing building and development adjacent to wetlands on the subject lot. It also removes
                   the wetland as a special area separated from development and subject to special protection.

                   Subdivisions in Accomack County

                   There have been over 160 subdivisions in Accomack County (Table 4-5) approved between 1972 and
                   1990. Of these 15 are campgrounds or other seasonal developments. These 15 subdivisions have
                   4,193 lots of which nearly 66 percent, or 2,765, currently have structures or trailers on them.
                   Another 44 subdivisions are trailer parks containing 2,813 lots. Nearly 56 percent, or 1,563, of these
                   are occupied by units. The remaining 113 subdivisions are primarily occupied by single-fan-dly
                   houses ranging in size from 2 to 5 bedrooms. There are a few duplexes, but these units are primarily
                   3-bedroom, 2-bath dwellings. Of the approximately 8,500 lots in these subdivisions, only 19 percent
                   or 1,627 are currently improved with structures.

                                   Table 4-5: Subdivision Development in Accomack County, 1972-1990

                         Type of                Number in          Number of            Number                %
                       Subdivision                County              Lots              Improved          Improved

                       Campground or                  15              4,193              2,765                 65.9
                       Seasonal /Vacation
                       Trailer Parks                  44              2,813              1,563                 55.6
                       Single or Multi-Fan-dly       104              8,449              1,627                 19.3
                       Total Subdivisions            163             15A55               5955                  38.5
                       Source:Accomack County Department of Environmental Affairs, Zoning Administrator's
                       Office, April 1991.



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                     Of the 163 subdivisions referenced above, at least 60 have central water systems. The remainder
                     have individual wells on each lot. Over 100 subdivisions have both individual water and septic on
                     each lot. Eleven subdivisions have central holding tanks for sewage that are pumped out
                     periodically. The septage is then disposed of in lagoons. One subdivision has both central water
                     and a central drainfield for wastewater disposal.

                     Subdivisions in Northampton County
                     There were about 150 subdivisions approved in Northampton between 1974 and early 1991. Between
                     1970 and 1980 appro)dmately 320 trailers and 602 other year-round housing units were added to the
                     e)dsting housing stock. If one assumes a similar proportion of development in the subdivisions
                     recorded, the results would be as those set out in Table 4-6. The number of lots recorded in these
                     subdivisions total 2,016. Of these, it is surmised that about 1,154 have been improved. It is further
                     surmised that 542 of the lots are improved with trailers, while 322 are improved with single
                     family houses. Accordingly,     an additional 290 camping and seasonal lots would be currently active.

                                          Table 4-6: Subdivision Development in Northampton County

                          Typeof                  Number               Number               Number                 %
                          Subdivision            in County              of Lots            Improved             Improved
                          Campground or              49*                431*                  290*                    67.3
                          Seasonal/ Vacation
                          Trailer Parks              34*                673*                  542*                    80.3
                          Single or Multi-Family     68*                912*                  322*                    35.3
                          Total Subdivisions        151               2,016                 1354                      57.2
                          Source: *Derived figures Director, Planning and Zoning, Northampton County;
                                   Northampton County Comprehensive Plan and Plan Background, July 1989.
                                   It is thought by county planners that all of these subdivisions are served by individual
                                   water and sewer.


                     THE CHESAPEAKE BAY PROGRAM ON THE EASTERN SHORE OF VIRGINIA


                     Introduction

                     The Virginia State Chesapeake Bay Preservation Act (CBPA) of 1988 - Chapter 21 of the Virginia
                     State Code, Sections 10.1-2100 through 10.1-2115 - sets out requirements for all local governments in
                     Tidewater Virginia to develop land use regulations based on the state code in order to protect water
                     quality in the Chesapeake Bay and its tributaries. Each locality will incorporate the new
                     regulations into their comprehensive plan, zoning bylaws, subdivision plans, and other land
                     development ordinances. Both counties on the Eastern Shore and the self-governing towns are
                     required to prepare such regulations. Under the CBPA where a town does not have planning,
                     zoning, or other such regulations, or chooses not to prepare regulations on its own, it may act to be
                     subject to the county program.

                     Basic Approach
                     The state program is overseen by the Chesapeake Bay Local Assistance Board. The Board is
                     comprised of nine members appointed by the Governor. The Board is staffed by the Local Assistance
                     Department, a state agency that provides technical support to the Board and technical advice and

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                   assistance to the local governments. The Board has developed regulations for the designation of
                   Chesapeake Bay Preservation Areas and for land use management to accomplish the aims of the
                   legislation in those areas. It also provides financial and technical assistance to local governments
                   where required. The Board must approve all locally prepared plans and assure compliance of each
                   local government with the Act, but is not responsible for specific decisions about particular sites in
                   the Preservation Areas. Those decisions will continue to be made by the local government based on
                   the locally prepared regulations.

                   The Chesapeake Bay Preservation Area (CBPA) contains three general land categories: the
                   Resource Protection Area (RPA); the Resource Management Area (RMA); and the Intensely
                   Developed Area (IDA). Very generally, an RPA is land at or near the shore of the Bay or tributary
                   which can protect water quality but, if damaged by development or other disturbance, can degrade
                   water quality. These areas include tidal wetlands, nearby non-tidal wetlands, tidal shores and
                   other lands whose disturbance would harm the area. An RPA must contain a buffer area along the
                   landward side measured from the landward face of the above features. Only redevelopment and
                   new, water-dependent uses can be developed in an RPA.

                   An RMA is land which protects the RPA. Development and other land disturbance in these areas
                   can have adverse effects on the RPA and ultimately degrade water quality. Floodplains, steep
                   slopes, soils susceptible to erosion, soils with a high degree of permeability, non-contiguous non-
                   tidal wetlands and lands required to protect water quality are to be included as RMA's. In some
                   cases the entire drainage basin of a water body may be designated as an RMA boundary. RMA's
                   must be designated landward of RPA's. Any use pern-dtted by local zoning can be developed in an
                   RMA, subject to certain performance criteria.

                   An IDA is an area that, due to previous development, may be located in an RPA or RMA.
                   Redevelopment and infill development can take place in these areas where little natural land area
                   remains. An IDA must be so designated if an area has more than 50 percent of its surfaces in
                   impervious materials, or is served by public water and sewer, or has a housing density of 4 or more
                   dwellings per acre.

                   State regulations were adopted in September, 1989 and became effective October 1 of that year.
                   Lots recorded after the effective date are subject to the regulations. However, local governments
                   may allow modification of the buffer up to 50 feet, and may not require a reserve drainfield (one of
                   the regulatory requirements) depending on the local program developed. All local governments are
                   to have their adopted local regulatory programs in place by November 19, 1991. Northampton's
                   program was incorporated into its Draft Comprehensive Plan in late 1990 and was drafted as an
                   overlay district for the zoning ordinance. Accomack's program was also drafted as a zoning overlay
                   district and is currently being assessed by the County Board of Supervisors.

                   Implications for Ground Water Protection

                   All locally prepared programs for Chesapeake Bay Preservation Areas (CBPA's) must meet
                   general performance criteria. These criteria are designed primarily to reduce nonpoint source
                   pollution of surface water and to protect sensitive lands from disturbance. The criteria include:

                           1 )     preservation of natural vegetation;
                           2)      restricting disturbance of land;
                           3)      restricting impervious cover;
                           4)      controlling soil erosion-especially in areas of susceptible soils and during land
                                   clearing construction and other land-disturbing activities, such as tillage;
                           5)      controlling the volume and quality of stormwater runoff;


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                            6)      controlling the overflow and leaching of septage from tanks and drainfields by
                                    regular, mandatory pumping;
                            7)      providing for reserve drainfield capacity for septic systems that equals the
                                    treatment capacity of the primary drainfield;
                            8)      requiring site plan review and the preparation of various studies such as a water
                                    quality impact assessment and a site plan review document;
                            9)      control of stormwater quality in agricultural and forestal areas within or adjacent
                                    to the RPA.

                    Of the above performance criteria, all relate to the ultimate use and condition of ground water.
                    However, several have the potential for more directly affecting ground water withdrawals and
                    quality.
                    Overflow and leaching of septic drainfields and tanks, especially when they are in close proxin-tity
                    to wells, can cause both immediate and long term effects on drinking water. The inclusion of
                    provisions for pumping out systems every five years is a start to controlling this overflow and
                    leaching. The requirement of provisions for back-up drainfields in areas that do not overlap the
                    original facility provides a longer-term solution to the problem.
                    Control of storm water quality in agricultural and forestal areas is also important to ground water
                    quality. This performance criteria is primarily directed toward the protection of surface water
                    from pollution by soil erosion, pesticides and fertilizers. These problems also can affect ground
                    water, but not simply through storm water runoff. The large amount of water used for irrigating
                    crops in the area can carry these pollutants into the soil as well. Where surface soils have a high
                    degree of porosity, especially where the subsurface soils are not clay or clay loam, chen-dcal
                    compounds used in agriculture and silviculture can be transmitted to ground water fairly quickly.
                    Where wells and watering ponds draw from this contan-dnated ground water, especially in the
                    upper aquifer, deleterious effects on humans and animals from consumption can be expected to be
                    noticed relatively quickly.
                    Another area where there may be beneficial effects on ground water quality is in the attention of
                    the Act and local programs to protect wetlands. Depending on substrata conditions, wetlands can
                    act as large filtration systems for broad areas that drain surface waters to the wetland. This water
                    may then penetrate to ground water aquifers at a faster rate than is possible when water seeps into
                    surrounding upland soils. The process of filtering out harmful substances is enhanced where
                    wetlands and marshy areas are protected by buffers of natural vegetation. Such a buffer zone is
                    called for in the Act and its attendant regulations. The capacity of the buffer to adsorb pollutants
                    is further increased where these substances are further controlled through agricultural best
                    management practices and erosion control plans.
                    In addition to the performance criteria set out in the Act, state agencies have called for further
                    performance standards. Briefly, these are as follows:

                      1 )   prevent any increase in pollution from new development;
                      2)    achieve a 10% reduction in pollution from redevelopment;
                      3)    achieve a 40% reduction in pollution from agriculture;
                      4)    limit any land disturbance to 60% of a site;
                      5)    preserve vegetation and limit impervious coverage;
                      6)    require a soil erosion and sediment control permit;
                      7)    stormwater from new development must be limited to pre-development levels;
                      8)    federal and state wetlands permits are needed before grading and clearing;



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                     9)    agriculture requires a Conservative Plan of Best Management Practices approved by the
                           Soil & Water Conservation District and put in place by 1995.

                   There are several points worth noting. The limitation of development of a site to 60 percent of the
                   total area is commendable. However, as can be seen in the studies done for existing land use (Table
                   4-3 ), some zone districts already limit building area to substantially less than this figure. There
                   may be substantial problems of pervious areas sufficient for individual well and septic systems, as
                   well as for any requirements for reserve drainfields, given such figures and the size of lots.

                   There are some differences in the CBPA regulations drafted by the two Eastern Shore counties. For
                   example, Northampton will require a Minor Water Quality Assessment of a proposed action if the
                   action disturbs less than 10,000 square feet of land. For Accomack, the same figure is 5,000 square
                   feet. In each draft there is considerable attention paid to requirements for RPA's, but less definition
                   to the requirements for RMA's. Requirements for IDA's are not included in either county's draft.

                   Some selected modifications of the current regulations shall be made to increase the potential for
                   ground water protection. Attention would have to be paid to space requirements for drainfields,
                   impervious surfaces, and developments adjacent to the buffer areas. Protection of wellhead areas is
                   one open space requirement that could be added, especially if the type of relationship between
                   underground aquifers and surface water bodies can be identified.



                   SUMMARY OF LAND USE ON THE EASTERN SHORE


                   Both Accomack and Northampton Counties are currently revising their zoning based upon recently
                   completed comprehensive plans, and the need to comply with the Chesapeake Bay Act. The
                   pattern of land use on the Eastern Shore has been very stable over the past. In summary, nearly 70%
                   of all land in agriculture and forestry uses is located in Accomack; nearly 66% of all land in
                   marshes, wetlands, and tidal areas is located in Northampton; nearly 78% of all residential land
                   lies in Accomack; over 96% of all industrial land lies in Accomack. Thus, the overall picture of land
                   use in the region is one of more intense development in Accomack County, even in the land use
                   categories often viewed as land extensive such as agriculture and woodlands. Agricultural,
                   residential, and industrial uses could have potentially significant affects for ground water
                    onsumption and water quality in Accomack County. Northampton County has the majority of its
                   land in marsh and wetlands, however, development densities could be quite high along the center
                   c

                   of the county, where the ground water is recharged.

                   Many of the land uses are allowed by right, meaning that permits and reviews by each county are
                   not required to determine if the development will have an impact on ground water use or quality. In
                   cases where potentially harmful uses are reviewed, the review process may need strengthening to
                   assure that such reviews are accomplished beyond that of the normal site plan or other process.
                   After the review, the uses which could have highly adverse long and short-term effects should be
                   monitored on a periodic basis to be sure that the ground water quality is not affected.

                   Both counties have a significant number of approved subdivisions with a high percentage of
                   undeveloped lots. Of the 15,455 approved lots between 1972 and 1990 in Accomack County, only 39%
                   have structures. In Northampton County 2,016 lots were approved during the same time period and
                   57% are improved with structures. This indicates that there is a significant potential to increase
                   the number of housing units, population, water needs, and wastewater disposal needs without
                   additional approvals required.





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                   The Chesapeake Bay Act once implemented in both counties, will help to control negative ground
                   water quality impacts from existing and future development with the requirements for periodic
                   pumping of septic systems, leach field reserve area requirements, site plan review, restrictions on
                   amounts of impervious areas on building lots, stormwater quality management considerations, and
                   the protection of valuable wetlands.














































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                 DELINEATION OF GROUND WATER SUPPLY MANAGEMENT AREAS
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                     SECTION 5: DELINEATION OF GROUND WATER SUPPLY MANAGEMENT
                                     AREAS



                     INTRODUCTION

                     HWH approached the issue of protection of the ground water of the Eastern Shore by first examining
                     the geologic and hydrologic conditions of the region, drawing upon existing technical literature.
                     Appropriate criteria for aquifer and wellhead protection were explored, utilizing accepted EPA-
                     approved criteria coupled with the hydrogeologic realities of the area. After appropriate criteria
                     were selected, a methodology was determined and implemented to map the protection zones.

                     SELECTION OF GROUND WATER PROTECTION CRITERIA

                     The three-dimensional character of the ground water flow system to the confined aquifer governed the
                     choice of the aquifer and wellhead protection area criteria. Initially, a criterion of time of travel
                     (TOT) was evaluated. With TOT, a distance is calculated from the well or wellfield that corresponds
                     to the amount of time it would take a particle of water (or contan-dnant) to move to the supply source
                     within a designated threshold (10-year TOT, 25-year TOT, etc.). TOT is an extremely effective criteria
                     in some hydrogeologic environments, particularly in unconfined aquifers in which the time it takes
                     precipitation to recharge the saturated zone is quite short. In that situation, recharge of water is
                     assumed to follow a piston-like pattern of flow downward through the unsaturated zones in a
                     relatively short time frame. TOT distance thresholds are then based on the time of travel of a particle
                     of water within the saturated zone, moving horizontally with the average velocity of the ground
                     water under pumping conditions.
                     On the Eastern Shore the character of ground water flow assumes more of a three-dimensional rather
                     than a two-dimensional nature. To obtain an accurate TOT calculation for a given well in a confined
                     system would have to account for the time taken for recharge water to pass through the unsaturated
                     zone, the time it takes to move both vertically and horizontally within the overlying unconfined
                     aquifer to the uppermost confining layer, the time it takes to move through that confining layer and the
                     time it takes to move horizontally to a well screened in the confined aquifer. When a three layer
                     system such as the Yorktown-Eastover aquifer is considered, the problems of determining TOT become
                     extremely difficult to solve with any degree of certainty. The data requirements and qualifying
                     assumptions to detern-tine the length of time it would take to move through such a complex pathway is
                     extensive; TOT is not an appropriate protection criterion in this hydrogeologic environment.

                     Criteria were selected for aquifer and wellhead protection based upon the unique hydrogeologic
                     conditions found on the Eastern Shore. The conceptual model indicates that the recharge area to the
                     most important aquifer (the Yorktown-Eastover aquifer) lies along the center of the peninsula.
                     Accordingly, protection criteria were determined to address this particular situation. Radial distance
                     was used for Zone 1, while hydrogeologic flow boundaries were used for Zones 2 and 3. Each ground
                     water supply management area is explained below along with the method used to map the protection
                     zones.


                     Zone I


                     Criteria:         200-foot radial distance around a well.

                     Rationale:        The need for a protective zone immediately around a well has more to do with human
                                       error than to hydrogeologic conditions. This zone is employed to maintain an area


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                                     around the well to prevent potential contaminants from moving into the aquifer via a
                                     poorly constructed or faulty annular sea] at the well. Wells that are poorly built or
                                     are old may lack the concrete or bentonite clay seal designed to prevent leakage from
                                     the surface down along the well casing into the aquifer. In addition, properly
                                     constructed seals may also break down over time and create a pathway for water an
                                     contaminants to flow into the well. A 200-foot radius around each well where
                                     virtually all activity is banned offers a measure of protection against accidental
                                     spills.

                   Method: The radial distance is established by drawing a scaled circle around the well on a map.


                   Zone 2 - Spine Recharge Area

                   Criteria:         Hydrogeologic boundaries based on recharge areas.

                   Rationale:        The conceptual model of the hydrogeology of the Eastern Shore indicates that the
                                     primary recharge area for the Yorktown-Eastover aquifer is located along the center
                                     of the peninsula. Assuming that precipitation falling on the surface of the Eastern
                                     Shore follows the flowpaths displayed in Figures 2-6 and 2-7, water falling along
                                     the center will penetrate vertically through the confining layer and recharge the
                                     confined aquifer. Recharge to the unconfined aquifer (the Columbia) has been
                                     estimated at between 12 and 26 inches per year (see below and Appendix E ).
                                     Recharge through the uppermost confining layer to the Yorktown-Eastover is much
                                     slower, governed by the low permeability of the confining clays and silts. That
                                     recharge rate is estimated at only about 0.10 feet per year (see below and Appendix
                                     E).

                                     Using the principle of conservation of mass, the amount of water that seeps
                                     through the uppermost confining layer to a pumping well at a low recharge rate
                                     over a large area must be balanced by an equal volume of water that recharges
                                     the unconfined aquifer at a higher rate. The volumes of water will be the same,
                                     but the recharge rates and the area required will differ. The land surface from
                                     which recharge flows into the unconfined aquifer is much smaller that the area
                                     through which recharge flows into the confined aquifer. Optimally, a full three-
                                     dimensional ground water flow model that accounts for the various differing
                                     permeabilities and thicknesses would be used to determine the recharge areas in
                                     the unconfined and confined aquifer and use particle tracking to back-track the
                                     starting points for water particles that are discharged by the pumping wells.
                                     That modelled contributing area would then be a logical choice for a protection
                                     zone.



                                     Without such a sophisticated model, a simpler solution was derived. Using a
                                     moderately conservative recharge rate of 9 inches per year for the Columbia aquifer,
                                     the amount of area within each of five areas (described below) to produce the
                                     permitted volume discharged was determined. That area was then divided equally
                                     on either side of the peninsula to form Zone 2. For this study, average values were
                                     used for recharge across the entire study area. Once the USGS model is available (see
                                     page 64), aquifer properties can be varied, and the model rerun.




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                     Method:           The largest users of ground water on the Eastern Shore were located and mapped.
                                       This group of twenty-six wells or wellfields (Appendix E) accounts for most of the
                                       total ground water discharge permitted on the Eastern Shore. The drawdown of the
                                       pumping wells was modelled analytically using a standard ground water solution to
                                       the flow equation, the Cooper-Jacob method. The individual drawdowns were then
                                       added to model the interference effects from neighboring wells throughout the
                                       Eastern Shore. The area of the peninsula was divided into five regions based on the
                                       grouping of wells, the amount of permitted pumpage and the contributing areas
                                       defined by contour mapping of the modelled drawdowns (Figure 5-1).
                                       The protection zone for each of the five areas was determined on the basis of
                                       recharge. The total amount of permitted pumping was determined for each area. The
                                       amount of land area required to balance that volume of pumping with a 9 in/yr
                                       recharge rate was calculated. The 9 inches was chosen as a conservative value to
                                       account for drought years. Since the recharge area was determined to be located along
                                       the center of the peninsula, the length of the spine was measured in each zone of
                                       contribution, and the width of the protection zone determined by dividing the
                                       recharge area necessary by the length of the spine available. This width ranges from
                                       1,530 feet to 4,660 feet but, to remain conservative, a larger 5,000-foot strip (2,500 feet
                                       on each side) was plotted along the spine throughout the entire peninsula (Figure 5-
                                       2).

                                       The 5,000-foot strip represents the size of surface area that contributes water to the
                                       wells in the Yorktown-Eastover aquifer. As the recharge flows downward in the
                                       Columbia aquifer it also moves horizontally towards the coasts (see Figure 2-7). The
                                       contributing area at the base of the Columbia has therefore grown wider. The
                                       transfer rate from the Columbia to the Yorktown-Eastover aquifers is then lower in
                                       order to maintain the same volume of water passing through the confining unit.

                     Zone 3 - Wellhead Protection Areas

                     Criteria:         Hydrogeologic boundaries using contributing areas of flow.

                     Rationale:        The moderate to low transn-dssivi ties found within the Yorktown-Eastover
                                       aquifer coupled with high levels of permitted discharge on the part of a number
                                       of major users creates substantial drawdowns in individual wells. These
                                       drawdowns interfere with one another, and since individual cones of depression
                                       are additive, the interference patterns serve to exacerbate the problems of
                                       excessive water level drop. Pumping from the confined Yorktown-Eastover
                                       aquifer produces a gradient on the overlying confining unit and the unconfined
                                       Columbia aquifer. In those areas, patterns of recharge and downward vertical
                                       flow occurring primarily along the central spine will be modified to some extent
                                       by the increased gradients, particularly where the confining unit possesses
                                       relatively high hydraulic conductivity or where the clays and silts are missing
                                       altogether. Those conditions could apply especially where the documented
                                       paleochannels cross the Eastern Shore peninsula. In such locales, recharge will
                                       occur from areas other than the central spine under conditions of substantially
                                       higher gradients created by pumping.
                                       To address this issue on a peninsula-wide basis, Zone 3 is proposed. Zone 3, based on
                                       ground water divides created by the superpositions of pumping patterns upon the
                                       ambient potentiometric surface, covers virtually the entire peninsula. The


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                                                                                                                                        OCEAN
                                                                  A         TIC                                           0


                                                                                                                                                     ts
                                                                                          -10     .20                                                                                   .5
                                                                                .2D
                                                                       -25


                                                                                                                                                        -20


                                                                                                                                  5                    -25
                                                                                                      .20
                                                        lei
                                                                     0                                                                               %5
                                                                                                                                                  .10


                                                                                                                                                        .5



                                                                                                   CHESAPEAKE







             -10- POTENTICIMETRIC SURFACE
                         CONTOUR












                  I LODD   0           22,000 33.ODO

                            scale (loot)


                                                                                                                              1,4









                                                                                                                                                                                        '000'

                                                                                                 ATLANTIC              OCEAN


                                             WPA-A
                                                                              WPA-B                 WPA-C                                               WPA-D                        WPA-E


                            Ilk.






                                                               r                                               ...... ....
                                                                                                                                                        ...............











                                                                                                                                          B W(
                                                                                                                 Cv4ES4PE4V(r

                           WELLHEAD PROTECTION AREA
                           (maximum permitted pumping rates)

                           WELLHEAD PROTECTION AREA
                           (existing pumping fates)


                           SPINE RECHARGE AREA






                    11.000   0            22.000 33.000
                              scale (lest)



                                                                                                                               5-5
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                                      employment of such a zone serves to establish formally how widespread the impact
                                      of ground water withdrawals has been on the hydrogeologic system of the Eastern
                                      Shore. Creating a zone of protection at the scale of Zone 3 re-emphasizes the
                                      dependence of the area on its ground water supply and how activities throughout the
                                      region, not simply along the central corridor, affect the quality and quantity of ground
                                      water.


                   Method:            The results of the analytical modelling to determine the amount of drawdown caused
                                      by pumping the major producing wells on the Eastern Shore were combined with a
                                      map of the pre-pumping conditions taken from the numerical flow modelling
                                      conducted by Bal, 1977. The resultant water level surface was then analyzed to
                                      ascertain ground water divides that form the boundaries to the zones of contribution
                                      to the Eastern Shore. See Figure 5-1 for the potentiometric map for permitted
                                      pumping rates. The zones of contribution constitute Zone 3 (Figure 5-2).


                   PHYSICAL DESCRIPTION OF EACH WELLHEAD PROTECTION AREA

                   The Wellhead Protection Areas (WPA's, Zone 3 ground water supply management areas), reflect
                   the contributing areas to existing wells under permitted pumping rates. Below is a breakdown of
                   certain activities within each WPA, along with a general geographical description. Please refer
                   to Figure 5-2 for the location of each WPA.

                   Wellhead Protection Area A - Chincoteague Area

                   Area: 27,000 acres
                   Number of Wells: 13
                   Number of VPDES dischargers: 17
                   Landfills: 2 closed
                   Lagoons: none

                   Of the WPA's, this wellhead protection area covers the least extent of upland. It includes
                   Chincoteague Island to the east, Captain's Cove to the north, Oak Hall to the south, and includes
                   the town of New Church and the NASA Wallops Station. The old northern landfill in Accomack
                   County (now closed) is located within this area, and apparently there is a closed landfill on
                   Chincoteague. Large wells serve Captain's Cove, the Town of Chincoteague, NASA Wallops Main
                   Station, and New Church Energy Association. These facilities also have discharge permits to
                   dispose of liquid wastes in the area. Water taken from the tap at Stoney Point Decoys, NASA
                   Wallops Flight Center, and NASA Wallops Island have all tested above 5 mg/l for nitrate-
                   nitrogen, with readings ranging from 7.11 to 11.5 mg/l.

                   Wellhead Protection Area B - Holly Farms (Tyson Foods) Area

                   Area: 43,000 acres
                   Number of Wells: 9
                   Number of VPDES dischargers: 6
                   Landfills: 1
                   Lagoons: 1

                   The towns of Withams, Hallwood, Nelsonia, and most of Wallops Island are located in this
                   wellhead protection area. To the east, it extends into the Atlantic Ocean, and to the west it
                   reaches as far as Route 698 near the Saxis area. This wellhead protection area contains the


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                    greatest visible contamination threat. Directly on the spine recharge area is the Northern
                    Landfill for Accomack County and one of the two Bundick septage lagoons, which is unlined. Any
                    contan-driation which reaches the ground water within this recharge area could eventually
                    contan-driate the Yorktown-Eastover aquifers. Water withdrawers and septage dischargers located
                    in this area are Holly Farms, which is second to Perdue in its pern-dtted water withdrawal rate,
                    Taylor Packing Company, and the NASA Wallops Island facility. The Atlantic Fire House is the
                    only known facility in WPA B to have nitrate-nitrogen levels above a negligible amount; a sample
                    taken in 1981 measured 5 mg/l.

                    Wellhead Protection Area C - Perdue Area


                    Area: 76,000 acres
                    Number of Wells: 15
                    Number of VPDES dischargers: 7
                    Landfills:none
                    Lagoons: 1
                    This is the contributing area created by pumping from Perdue, Byrd Foods, the towns of Onancock
                    and Parksley, and the Accomack County Nursing Home. Because of large amounts of industrial
                    water withdrawals, this wellhead protection area is the largest one on the peninsula. The current
                    pumping rates, dominated by Perdue Inc., show a drawdown area almost as large as the drawdown
                    expected for the maximum, pern-dtted pumping rates. The WPA extends into both the Bay and the
                    Atlantic, and includes Bloxom to the north and Melfa to the south, and Accomac, Parksley, Onley,
                    and Onancock in the central portions. WPA C contains the Boggs septage lagoon. Two public water
                    supply wells for the Town of Parksley have had nitrate nitrogen levels ranging from 5.65 to 8.5 mg/I
                    during testing intervals between 1974 and 1989. An observation well sampled in 1980 measured 10
                    mg/I for nitrate-nitrogen.

                    Wellhead Protection Area D - Exmore Area


                    Area: 65,000 acres
                    Number of Wells: 9 and 1 proposed
                    Number of VPDES dischargers: 9
                    Landfills: 1
                    Lagoons:1
                    WPA D covers the border of Accomack and Northampton Counties. The southern landfill for
                    Accomack County and a Bundick Lagoon is located within its boundaries. To the east, the
                    boundaries cover most of Paramore Island and Hog Island, and it extends far out into the
                    Chesapeake Bay on the west side. The villages of Keller and johnsontown are the north and south
                    extents of wellhead protection area B, respectively. Also included are Pungoteague,
                    Wachapreague, Exmore, and Nassawadox. Wells are in use for the town of Exmore, Virginia
                    Landing Campground, the Accomack-Northampton Hospital, and American Original Foods.
                    Peaceful Beach Campground plans to install a well in this wellhead protection area. An
                    observation well on Churchneck has measured very high nitrate nitrogen levels, ranging from 13.0
                    to 24.0 mg/l.







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                  Wellhead Protection Area E - Cape Charles Area

                  Area: 52,000 acres
                  Number of Wells: 17 plus 7 proposed
                  Number of VPDES dischargers: 13
                  Landfills: 1
                  Lagoons: none

                  This wellhead protection area is the most southern on the peninsula, not quite reaching
                  Fisherman's Island. Similar to WPA D, its boundaries include most of the marshland on the east,
                  and extend out to a large distance into the Bay. Machipongo is the northernmost town, and
                  Eastville' Cheriton, Cape Charles, and Townsend are all included in the protection area. Major
                  wells in the area are presently proposed but pem-titted, and include wells for the DiCanio and
                  Brown & Root communities near Cape Charles. Current water withdrawers; are the towns of
                  Eastville and Cape Charles, America House Motor Inn, Sea Watch International, KMC Foods, and
                  Bayshore Concrete Products. The Northampton County Landfill is also located within this area. A
                  Brown and Root well sampled in 1977 had a nitrate-nitrogen level of 17.0 mg/l, and an observation
                  well near Oyster exhibited nitrate-nitrogen levels ranging from 6.9 to 9.0 mg/l.






























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                   SECTION 6: WATER BALANCE

                   Because aquifer and wellhead protection is so intimately tied to the issues of water quality and
                   quantity, some quantification of the amount of recharge both to the unconfined and confined
                   aquifer systems was needed. The estimate of the available water could then be compared to
                   the amount extracted in terms of current, permitted and future yields.

                   RECHARGE TO THE COLUMBIA AQUIFER

                   An estimate of the amount of water recharging the unconfined Columbia aquifer as made using a
                   standard water budget calculation (Appendix E) following the approach detailed in Dunne and
                   Leopold, 1978. A water budget is calculated by creating a "balance sheet" of hydrologic inputs
                   and outputs to the system. The input to the system is precipitation. Average values for
                   monthly precipitation from the weather station at Painter, Virginia were used, representing
                   six years of record (1985-1990). Outputs from the system include the amount of water
                   evaporated directly or transpired indirectly to the atmosphere, estimated using an approach
                   from Thomthwaite and Mather (1955) (Appendix E). The Thornthwaite and Mather approach
                   is designed for use in temperate and humid environments and is an appropriate choice to
                   estimate potential evapotranspiration (ET) on the Eastern Shore. Where ET is greater than
                   precipitation, a potential water loss develops and accumulates during the dry months (June,
                   July and August). The amount of moisture held in the soil (a function of soil type and plant
                   rooting depth) will be reduced because of this accumulated water loss. Calculations are then
                   made to estimate the actual ET and to determine the amount of water available for runoff and
                   recharge. The water budget approach resulted in an estimate of 17 inches per year of recharge
                   to the unconfined Columbia aquifer on the Eastern Shore, assuming 50 % runoff, 12 inches per
                   year with 60% runoff and 26 inches per year with 40% runoff.

                   The water budget modelling is fairly robust with regard to most of its components. Temperature
                   and precipitation records show only moderate scatter, characteristic of a temperature climate.
                   The fact that relatively little soil moisture deficit develops is typical with the climatic
                   regime of the Eastern Shore. Where the model does show sensitivity is in the estimate of the
                   amount of runoff that takes place. The Soil Conservation Service (SCS) models of runoff
                   calculations are only applicable to small catchments, and empirical estimates for runoff
                   percentages are difficult to obtain at the scale of the entire peninsula. Given the permeable
                   nature of soils on the Eastern Shore, a 50% estimate is reasonable (Dunne and Leopold, 1978). If
                   40% is estimated to run off, the recharge estimate jumps to approximately 26 inches per year. If
                   60 percent runoff is estimated, about 12 inches per year recharges the aquifer.

                   The volumetric amount Of recharge is determined by multiplying the recharge rate by the area
                   of the peninsula. Using an area of 400 square miles and 17 inches of recharge per year, the
                   volumetric recharge to the unconfined aquifer is approximately 324 million gallons per day.
                   Most of the withdrawals from the surficial aquifer consist of agricultural extractions, and many
                   are undocumented. However, it can be fairly safely maintained that the withdrawals do not
                   approach even within an order of magnitude of the amount being recharged. The quantity of
                   water within the Columbia aquifer appears to be of little concern.

                   RECHARGE TO THE YORKTOWN-EASTOVER AQUIFER

                   The days and silts separating the unconfined Columbia and the confined Yorktown-Eastover
                   aquifers range in thickness from 20 to 100 feet. The permeability of this confining layer is low,
                   but precisely how low is difficult to determine empirically. To calculate the flux across the
                   confining layer for transient (time-dependent) conditions using Darcy's Law, some value for


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                                                                  6-1







                     hydraulic conductivity (permeability) has to be used. To avoid this problem, and to obtain a
                     conservative estimate of recharge to the Yorktown-Eastover aquifer, HWH used as steady
                     state approach to calculate recharge. Recharge was determined via a cross-sectional model for
                     the confined ground water system. The governing differential equation for one-dimensional
                     flow at steady state was integrated and boundary conditions appropriate to the Eastern Shore
                     used to determine the constants of integration. The result was an equation that could be solved
                     for a recharge rate (see Appendix E). The recharge rate was multiplied by the area of the
                     confining layer receiving recharge to determine the volumetric quantity of water reaching the
                     confined system.
                     The coefficients necessary to solve the derived equation are aquifer transn-dssivity, hydraulic
                     head (water level), and the width of the peninsula. To examine the sensitivity of the
                     analytical model, a range of values were used to determine an estimate for recharge. The
                     average width of the peninsula is about 8 miles in Accomack County and about 6 miles in
                     Northampton County, although sections exist that are considerably narrower. Calculations
                     were made for widths of 4,6, and 8 miles. Transmissivity values found in geologic reports of the
                     Eastern Shore varied considerably, ranging from less than 1000 ft2 per day to over 5000 ft2 per
                     day. The modelling incorporated a range of transn-dssivity from 500 to 5000 ft2 per day. Values
                     from the potentiometric surface map of Bal, 1977 were used for hydraulic head at the ground
                     water divide, varying from 15 to 26 feet above mean sea level.
                     The results show that recharge to the confined Yorktown-Eastover aquifer is very slow.
                     Calculated rates ranged from 0.01 ft/yr under the worst case conditions to 0.85 ft/yr for a
                     somewhat optimistic scenario of narrow peninsula width coupled with high transmissivity and
                     high hydraulic head. The average recharge rates for the 6 and 8 mile wide peninsula scenarios
                     was 0.13 and 0.07 ft/yr, respectively. These average recharge rates take into account the
                     average widths of the two counties at the selected average transmissivity values, but do not
                     account for the large variability (more than a factor of two) in each of these numbers as
                     discussed in Appendix E (Page E-6). These average rates also coincide with the conceptual
                     model of a fairly restrictive confining layer separating the Columbia and the Yorktown-
                     Eastover aquifer.
                     Recharge in the model changes directly in proportion to transmissivity increases and hydraulic
                     head increases, but reacts oppositely to changes in the width of the peninsula. The model is
                     quite sensitive to differences in peninsula width. With a decrease of 2 miles (8 to 6 miles, or 6 to
                     4 miles) recharge more than doubles. The model is also sensitive to values of transn-dssivity.
                     Over the anticipated range of 500 to 5000 ft2/day, recharge values approximately double with
                     each 1000 ft2/day increase. The model is least sensitive to hydraulic head, primarily because
                     of the restricted range of heads that are used. Each 2 foot increase in head translates to about
                     0.01 ft/yr increase in recharge.
                     While the rate of recharge is quite low, the volumetric total of water that enters the confined
                     system is fairly large. However, the conceptual model demonstrates that recharge does not
                     occur across the entire area of the confining layer. Rather, it occurs predon-dnantly over the
                     central portions (Figures 2-6 and 2-7). Therefore, multiplying the calculated recharge rate by
                     the entire area of the peninsula on the assumption that all of the confining layer surface
                     pern-dts recharge would incorrectly inflate the volumetric total entering the confined system.      A
                     range of areas smaller than the entire Eastern Shore was used to estimate the volumetric
                     recharge to the confined Yorktown-Eastover aquifer (Appendix E).




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                   Using an area of 200 mi2 and a recharge rate of 0.10 ft/yr (averaging 0.13 and 0.07 ft/yr), there
                   is some cause for concern in terms of water quantity in the Yorktown-Eastover aquifer. At a 0.10
                   ft/yr recharge rate, pumping at the permitted amount of 15.6 MGD would create a deficit
                   situation, in effect, mining the ground water of the confined system. Even when considering a
                   recharge area of 300 md2, the volumetric total at 0.10 ft/yr is within 3 MGD of currently
                   permitted use.

                   If the Yorktown-Eastover aquifer is receiving recharge at a rate of 11 MGD, and the maximum
                   withdrawal volumes could reach 15.6 MGD according to VAWCB issued permits, then
                   significant problems could develop in the future. Continuous drops in hydraulic head and
                   increases in chloride levels have been observed in VAWCB test wells in the vacinity of the
                   largest industrial withdrawal wells. If maximum withdrawals reach 15.6 MGD, then salt
                   water intrusion (lateral and upconing), well interference and water quality degradation of the
                   Yorktown-Eastover aquifer, already observed near major industrial users, will be aggravated.

                   In view of these results, serious consideration should be given to (a) better quantification of the
                   amount and distribution of recharge that enters the confined system, (b) careful examination of
                   additional permits for large volume water users that would increase the amount of pumpage
                   significantly beyond current levels, and (c) reevaluation of existing permits relative to actua I
                   use and need.


                   SALT WATER INTRUSION

                   Serious questions exist relating to the issue of sheer water quantity that can be extracted from
                   the Eastern Shore's confined system. Of equal importance to the amount of water being
                   extracted is the issue of where the water is being taken from. In particular, consideration for
                   the problem of salt water intrusion has to be considered.

                   Salt water intrusion to a fresh water aquifer can occur in several ways. Intrusion can occur from
                   lateral inflow of salt water into the fresh water zone. In this scenario, salt water is viewed as
                   a wedge that pushes in to the fresh water lens as fresh ground water head declines because of a
                   drop in area] recharge or from pumping of wells in the fresh water zone (Figure 6-1). Several
                   analytical models have been developed for the analysis and description of flow in a fresh
                   water zone overlying a static body of salt water including the standard Ghyben-Herzberg
                   equation and an approach by Glover, 1959.

                   With confined aquifers, salt water can also intrude vertically through confining layers in
                   response to reversals of gradient. As pumping proceeds or as area] recharge to the fresh water
                   aquifer declines, the hydraulic head in the fresh water zone becomes less than that in the salt
                   water zone. Flow that originally moved upward from the fresh water zone through the
                   confining layer and discharging to the salt water zone reverses. As a result, salt water leaks
                   through the confining layer into the fresh water zone. This problem particularly afflicts wells
                   located along coastal areas.

                   The wedge-like movement of salt water into fresh water zones and the leakage through
                   confining layers from gradient reversals was the subject of the recent U.S. Geological Survey
                   study on the Eastern Shore, using the SHARP interface model (Richardson, in press). That
                   report remains in the U.S.G.S review process and is not yet published. When the results do
                   become available, they should be closely examined to assess the impact of lateral intrusion and
                   intrusion through confining layers, particularly on high volume wells located near the coasts.




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                                                                   Figure 6-1

                                              SALT WATER UPCONING FROM WELL


                                 WEST                                                                                 EAST



                                                                         Pumping Well
                                                                                                         Piezometric
                              Chesapeake                                                                   Surlace      Atlantic
                                                                                                                        Ocean
                                  Bay
                                                                                                 . . . .......



                                                          r                                      .... .. .. .
                                                                                                .... ....... .... ..





                                                                          ....... ....











                                         Sail
                                                                                                                  sell
                                       .:Gmun                                                                     mund
                                                                                                         Iiii       ter




                                          Fresh Water Aquifer

                                         -Fresh Water Aquitard
                                                                                                                 7




















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                 regardless of pumping rate, and a number of analytical equations have been developed to
                describe this movement of salt water (McWhorter and Sunada, 1977). If a well pumps at too
                high a rate, the salt water upcone will reach the well and contaminate the supply source.
                Therefore, pumping fresh water from an aquifer underlain by a salt water zone must be done
                using very small drawdowns to prevent upconing from reaching the well. It is possible to obtain
                an upconing of the salt/fresh interface that is stable for a given pumping rate, the thickness of
                fresh water zone and particular well construction. In practical terms, the salt/fresh interface is
                usually stable if the upcone rises less than one third of the distance between the bottom of the
                well and the original, non-pumping interface elevation.

                                     Figure 6-2 Upward Vertical Migration of Salt Water




                                                                          land surface


                                                               water t                         M51
                                                           -------------



                                   ocean
                                                                              fresh water








                                               saline water






                Several analytical solutions have has been developed to predict the maximum discharge a
                well can produce given a particular thickness of fresh water, hydraulic conductivity, and
                distance to a well screen. Three were exan-dned for use on the Eastern Shore (Appendix E). The
                models are designed to predict the recommended maximum rate a well should pump to avoid
                the problem of moving the salt water upcone beyond the critical level of stability. Two of the
                models selected (McWhorter, 1972 and McWhorter and Sunada, 1977) are designed for cases of
                partial penetration of a well, in circumstances where the screened portion of the well is small
                in relation to the total depth, a common factor to virtually all wells on the Eastern Shore. The
                third approach (Bennett, 1968 in Reilly and others, 1987) incorporates a recharge factor into
                the calculations.

                The upconing models were applied for conceptual purposes to obtain an idea of the magnitude of
                the problem of upconing. The aquifer was modelled as a single confined unit, ignoring
                intermediate confining and sen-d-confining layers to simplify the analysis. Parameters needed
                for the modelling (e.g.,thickness of the undisturbed fresh water zone, position of well screen,
                hydraulic conductivity, etc.) were determined for a high volume producing well, Perdue #2,
                taken from the literature. In particular, the elevation of the pre-pumping salt/fresh interface
                was designated at the elevation of the the 250 mg/I chloride level, calculated by subtracting
                the mapped 250 mg/I chloride surface elevation (Fennema and Newton, 1982) from the pre-
                pumping water level surface elevation (Bal, 1977). Water with more than 250 mg/I tastes salty


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                    and is generally unacceptable for most domestic and industrial uses. While the 250 mg/1
                    chloride level does represent a limit of potable water, it is not a true salt/fresh water
                    interface. The allowable discharges produced by all the upconing models are directly
                    proportional to the difference in density between the salt (usually sea water) and fresh water,
                    generally estimated at 0.025 mg/l. The density differences between fresh water and water
                    with 250 mg/1 chloride is negligible, resulting in trivially small allowable discharge rates. To
                    make use of these analytical tools even for conceptual purposes, the density difference had to be
                    maintained as that between sea and fresh water.

                    The results (Table 6-1) show the models predict considerably lower levels of pumping discharge
                    rates than either permitted or existing rates in order to maintain a stable upcone. The ,
                    predicted rates for this well range from a low of 20 gpm from an extremely conservative model
                    to 80 gpm, using the Bennett and other, 1968 model that incorporates recharge. However, if a
                    true salt water interface existed at the 320 foot level (with a chloride concentration of
                    approximately 30,000 mg/1), this well and most all high volume wells on the Eastern Shore
                    would have been contaminated at either their permitted or actual rates.

                                            Table 6-1: Salt Water Upconing Modelling Results





                                   Well:            Perdue #2

                        Model Input Parameters                                    IDischarge Data

                        Screen bottom elevation         253     ft msl              Permitted discharge (gpm) 503
                        Salt/fresh interface            320     ft msl                  Actual discharge (gpm) 278
                        Thickness of fresh water        340     ft
                        Areal Recharge                  0.10    ft/yr
                        Hydraulic conductivity          37.5    ft/day

                        Modelled allowable discharge to prevent upconing

                        Model from McWhorter, 1972                                         20          9PIn
                        Model from McWhorter and Sunada, 1977                              46          8PIn
                        Model from Bennett and others, 1968                                80          SpIn





                    The reasons why sea water does not flow from the wells of the Eastern Shore is a combination of
                    several factors. The models assume a sharp interface between the salt and fresh water, a
                    phenomenon that rarely occurs in field conditions, especially if pumping is intermittent.
                    Instead, the salt/fresh interface usually forms a gradational zone from highly saline or
                    brackish water to fresh water. Also, as indicated above, the interface position used in the
                    modelling was not assumed to be a pre-pumping true interface (approximately 30,000 mg/D.
                    The model instead used a post-pumping 250 mg/I chloride level, which is not a true salt
                    water/fresh water interface. The actual position of salt water lies somewhat below the level
                    used in the modelling, below the confining layer that separates the lower Yorktown-Eastover


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                   modelling was not assumed to be a pre-pumping true interface (approximately 30,000 mg/1).
                   The model instead used a post-pumping 250 mg/I chloride level, which is not a true salt
                   water/fresh water interface. The actual position of salt water lies somewhat below the level
                   used in the modelling, below the confining layer that separates the lower Yorktown-Eastover
                   aquifer from the underlying unit, the St. Mary's Formation. None of the models used
                   incorporates a low permeability unit into the calculations, and salt water intrusion from
                   upconing would be slowed by the presence of a lower boundary of silts and clays.
                   The results of this modelling should serve not as any sort of regulatory tool but as a warning
                   that large discharges will promote salt water contamination from upconing unless pumping
                   rates and intensities are regulated. Also, the primary issue at hand is not whether sea water
                   with a chloride concentration of 30,000 mg/I is actively intruding into the fresh water aquifer.
                   The more important question is whether water that possesses chloride concentrations of 250
                   mg/I and is essentially useless for direct consumption, either as drinking water or as industrial
                   use water, will be drawn into the wells. In all likelihood, that is probably happening now in a
                   number of wells on the Eastern Shore despite the fact that samples from most wells show lower
                   overall concentrations. Most wells completed in the Yorktown-Eastover aquifer have screens in
                   all three layers and draw water from all three. The lower Yorktown-Eastover is often the
                   least transmissive of the three and contributes the least water. The overall result is that a
                   mixing of water occurs, and samples taken from a given well represent the bulk chemical
                   signature of all three layers. Water in the upper two layers is not likely to have been affected
                   by high chlorides yet, and dilution masks the elevated concentrations of chloride from the
                   lower section. Salt water upconing will occur with pumping, and careful management of the
                   resource is required to avoid irreparable damage to the fresh water aquifers.


























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                   SEMON 7: BUILDOUT



                   DEVELOPABLE LOT/LAND USE ANALYSIS

                   Of the total land area on the Eastern Shore (about 537,000 acres), approximately 38 percent or 206,000
                   acres are wetlands and coastal islands, not suitable for residential, agricultural or industrial use.
                   Approximately 53% of the land area on the Eastern Shore is under agricultural use or forestry. The
                   remaining 9% of the land is under residential use (3.2%), commercial/industrial use (0.6%), in the
                   public domain (2.4%), or other uses (2.3%) (Table 4-1, p. 4-3.).
                   With the exception of sewage treatment plants servicing the towns of Cape Charles and Onancock,
                   existing development on the Eastern Shore relies on individual subsurface disposal systems for sewage
                   treatment. No large-scale sewering is anticipated in the future. Residential development is scattered,
                   with a low density pattern of development overall. Commercial and industrial development is
                   concentrated along the center strip of both counties, following Route 13. Drinking water is supplied by a
                   combination of public water supply and private wells.

                   Zoning requirements (dimensional and use) vary widely, both within the counties, and within the
                   towns. Land use in Virginia is regulated at the county level, with the exception of the areas within
                   incorporated towns. Land use in these areas is regulated by the towns themselves.

                   The authority for local governments to zone land in Virginia is granted by the Virginia General
                   Assembly and can be found as Article 8 of the Code of Virginia. The Virginia Zoning Code cites ten
                   general purposes for zoning including "to protect surface water and groundwater" (VA Code Ann. sec.
                   15.1-489). The Zoning Code also authorizes conditional zoning, site plan ordinances, and the provision
                   for variances.

                   In addition, local governments are required to develop a comprehensive plan for "the physical
                   development of the territory within its jurisdiction" ( VA Code Ann., sec. 15.1-446.1). The
                   comprehensive plan becomes the general plan for development and the basis for the formulation of
                   zoning ordinances in the local jurisdiction. Specifically, the code requires local governments to include
                   in their plans "the designation of areas for the implementation of reasonable groundwater protection
                   mea5ures" (VA Code Ann,. sec. 15.1-446.1).

                   Local control over development can also be found in the State's law controlling land subdivision (VA
                   Code Ann. sec. 15.1-465). This authority can be particularly important in an area such as the Eastern
                   Shore where very little land is currently subdivided into smaller residential lots.

                   A land use control measure that recently became available for use in Virginia is found in the
                   Chesapeake Bay Preservation Act (VA Code Ann. sec. 10.1 -2100). This new law passed in 1988 requires
                   that counties, cities, and towns of Tidewater Virginia incorporate general water quality protection
                   measures into their comprehensive plans, zoning ordinances, and subdivision ordinances. This
                   authority provides very general and broad powers to local governments in Virginia to control land uses
                   that may impact on water quality.

                   Methods

                   The primary purpose of buildout, or developable lot, analysis was to evaluate the impacts of existing
                   and potential land uses on ground water quality. The analysis therefore focused on the Zone 2 spine
                   recharge area, as delineated in this study.



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                    The buildout analysis followed a three step process. First, Zones 2 and 3, as delineated in this study,
                    were transferred onto US Geological Survey 1:25,000 scale topographic quadrangles for Northampton
                    County and Accornack County land use district maps, also at 1:25,000 scale.

                    Secondly, existing land uses within the spine were documented. The potential for further development
                    was determined from future land use maps prepared for both counties, and the information was
                    transferred onto the set of 1:25,000 scale maps. An example of future land use within the spine is shown
                    on Figure 7-1.

                    The Soil Conservation Service (SCS) identified the Nimmo-Arapahoe soil association as the only
                    upland soil type in the two counties that is considered undevelopable (R. Lewis, personal
                    communication, 1991). Areas with these soils were identified on the land use maps, and analyses were
                    conducted with and without inclusion of these areas. Small regions of hydric soils were not factored
                    into analyses.

                    Finally, areal extent was measured for each future land use class, subdivided by county, ground water
                    protection zone, and soil class. Fifteen percent (15%) of developable land was taken out for roads
                    within each land use category.

                    All data used in the analysis was entered into a computerized spreadsheet program (Microsoft Excel),
                    to aid sorting and analysis. The spreadsheet was programmed to perform the necessary calculations for
                    the various buildout scenarios. The total future number of units was calculated by taking the total land
                    area within each land use category in each protection zone, subtracting out 15% for roads and poorly
                    drained soils. The remainder was divided by the permitted number of lots per acre under current zoning
                    (Northampton) or recommended zoning (Accomack Comprehensive Plan, 1989). Table 7-1 lists
                    parameters used.

                                            Table 7-1: Minimum Lot Sizes Used in Buildout Analysis

                                            Accomack Cotmjy                                    Northampton Counjy
                       RR: Rural Residential         1 unit/acre                      Residential               20,000 ft2
                       R-1: Residential              3 units/acre                     Agriculture               43,560 ft2
                       R-2: Residential              2 units/acre
                       Agdculture:                   1 unit/5 acres
                       Source: Accomack County Comp. Plan, 1989               Northampton County Zoning Ordinance, 1990

                    The analysis results have important implications for the assessment of nitrogen contamination of
                    ground water and for the development of appropriate regulatory approaches in protecting ground water
                    quality on the Eastern Shore.

                    Buildout Assumptions

                    For incorporated towns in Accomack County certain assumptions were made in order to complete the
                    buildout analysis. Each town has its own zoning which is not included in the Future Land Use Plan for
                    the County. The following assumptions were made:

                    1) The percentage of the town which lies within the spine was determined by taking the ratio of acres
                       of town within the spine to total acres of incorporated town.
                    2) The breakdown of land use types was assumed to be equivalent to that of the entire county, leaving
                       out agriculture, parks, and marshland. In Accomack County, it was estimated that 75% is
                       residential, 1.8% is trade, 17.5% is industrial, and 5.3% of is institutional. These percentages were


                        Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
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                         Fig= 7-1:
                    Example of Future Land Use Within Spine Recharge Area



                                                                                         TOW
                                                                                         Of
                                                                                         Wfa





                                                                 ............ -------- .......

                                                                                       sov
                                                               ............. ......
                                                                                            Arm








                                                                                              .... ..........



                                                                                        P 13::'
                                                                                                                 ... ..... ...



                                                                                                                         ..........






                                                                                own
                                                                               of
                                                                               Keller



                              R                                                                                          RR: Rural Residential (1 unit/acre)
                                 - 1: Residential (3 units/acre)           Industry             Institutional

                              Agricufture (I unit5



















                                 Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
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                         multiplied by the acres of each town which fall on the spine. Ain estimate of acreage by land use
                         within the town was thus achieved.
                     3)  Using the estimated potential residential acreage in each town from (2), the number of potential
                         dwelling units was calculated. An average of 2 units per acre was used.

                     For Northampton County, there are two types of residential land delineated on the future land use
                     map, Rural Residential (and village area) and Urban Development Area. In the Comprehensive Plan,
                     each urban development area is broken down into residential, commercial, industrial, roads/railroads
                     and public land areas. The maps showing the locations of these types are inadequate for transferral to
                     the USGS quadrangle maps. Therefore, land use within the urban development areas was estimated.
                     Proportions of each land use type within the spine were assumed to be equivalent to that of the area as
                     a whole; and residential land was separated from other types within each urban development area.

                     Calculations within incorporated towns and Urban Development Areas are included in Tables 7-3 and 7-
                     4.



                     BUILDOUT ANALYSIS RESULTS

                     Buildout results are summarized in Table 7-2; complete results are shown in Table 7-5.

                                                               Table 7-2: Buildout Summary

                                                Existing Units             Total Acres       Res./Ag. Acres          Potential Units
                         Accomack County        Counjy-wide                within sp@ine     within spine            within spine
                         developable soils                                 17,140            16,561                  15,893
                              all soils                  15,840            22,147            19,901                  16,470

                         Northampton County
                              all soils                  6,183             16,921            15,535                  21,207


                     In both counties, the potential number of single-family dwelling units within the spine recharge area,
                     according to current plans, is greater than the number of units that currently exist within the entire two
                     counties. While the number of potential housing units may be striking, development is currently slow on
                     the Eastern Shore of Virginia. Indeed, the population has actually decreased in the past decade.
                     Consequently, there is opportunity to enact management tools to control future development and thereby
                     protect ground water quality and quantity.

                     BUMDOUT ANALYSIS SLUAMARY


                     The buildout analysis used a computerized spreadsheet approach to determine the maximum number of
                     future residential units in both counties. The buildout focused on land areas within the delineated spine
                     recharge zone (Zone 2) to the Yorktown-Eastover aquifer, since this area would most likely affect
                     public water supply quality. Using minimum lot size requirements according to each county's
                     comprehensive plan, the maximum number of units or houses that could be possibly built was calculated.
                     In Accomack County this resulted in 16,470 potential units in the spine recharge area. For Northampton
                     County, the maximum potential number of units was calculated to be 21,207 (Table 7-2). As discussed
                     previously, this results in more potential units than that which currently exist within each county.




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                                                    Table 7-3c Calculations for Buildout Within Incorporated Towns, Accomacic County

                               CALCULATIONS OF CURRENT DWELLING UNITS WTI`HIN SPINE

                               Incorporated      Acres within           Total acres          % of town       1990cmust Estimated dwelling
                                   Town                spine                 oftown          withinspine dwellingunits unitsinspine

                               Accornac                173                   262                   66                  205               136
                                                       83                    486                   17                  276               47
                                                       154                   177                   87                  191               166
                               ,Keller         1       211          1        214                   98      1           107       1       105             1
                               IPainter        1       184          1        415             1             1           113       1       5D
                               lbelle Haven 1          408          1        3M              I     so      1           245       1       122

                               CALCULATIONS OF LAND USE WITHIN TOWNS


                                                  Acreage in        Estimated acreage                                            Estimated Acres
                                Land Use           county           within towns M)          Accomac                   Onley     Melfa        Keller Painter Belie Haven

                               Residential             4.3                   75                    131                 63           116          159         138          308
                               Trade                   0.1                   2                     3                   2            3            4            3            7
                               Industrial              1.0                   is                    30                  is           27           37          32            71-
                               lInstitutional          0.3                   5                     9                   4            8            11          10    1       22
                               117otal                 5.7                   100                   173                 84        1  154          211     1   184   1      408

                               MAXEAUM POTENTIAL DWFELLING UNITS WITHIN SPINE


                                                   Estimated        Residential aczes        Average           Potential         Existing Nlaximum
                                  Town         residential acres subtracting 15%             units/acre      dwellings in        dwellings Additional
                                                                       for roadwa                                      spine     in spine Units Possible
                               Accornac                131                   ill                   2                   Z22          136               86
                               Onley                   63                    54                    2                   107          47                60
                               Melfa                   116                   99                    2                   197          166               31
                               ,Keller         1       159                   131                   2                   270          105    1          165          1
                               11'ainter               138                   118                   2                   2W           so                185
                               Bell* Haven             305                   261                   2                   523          122               401          1



                                                  Table 7-* Calculations for Buildout WIthin Urban Development Areas, Northampton CAUMY



                               CALCULATIONS OF CURRENT DWELLING UNITS WITHIN SPINE

                                Urban Development             Acres within       ToW acms          % of area           CurmatPopulation Estimated         #personst Estnumberof
                                          Area                      spine                    of area within spine      (Comp. Plan)      Pop, in spine     dwelling dwelling units
                                                                                                                                                         (1990 Ono")        in spine
                               Exmore/WWis       Wharf              1,164                    4,225       28                      Z684         740              2.1             350
                               Nassawadox                           12M                      i'm         66                      1,775        1,174            2.1             556
                               Eastville                            1,423                    2277        63                      800          500              2.1             237
                               lCheriton/Cape Charles 1             1,448       1            5,428 1     27    1                 4,274   1    1,140      1     2.1     1       540       1

                               LAND USE WITHIN URBAN DEVELOPMENT AREAS ACCORDING TO COMPREHENSIVE PLAN


                                      Land Use                   Exmore/        Nassawadox Eastville                   Cheriton/
                                                              Willis Wharf                                             Cape Charles
                               Residential                          65                       88          77                      66
                               Commercial                           5                        7           3                       4
                               Industrial                           6                        2           2                       7
                               Roads/Railroads                      17                       1           is                      19
                               jPublic                     -1       7           1            2     1     2     1                 5       1

                               hWaMUM POTENTIAL DWELLING UNITS WITHIN SPINE

                               Urban Development Area           Estimated       Minimum lot Potential                  Estimated           Nlaximum
                                                           residential acres                 size  dwellings in        existing          Additional
                                                              within spine                   (acres)     spine         dwellints in spine Units Possible
                               Exxnore/Willis Wharf                 7S9                      0.46        1,650                   350          1,300
                               Nassawadox                           1,076                    5.46        2,340                   556          1,784
                               Eastville                            1,096       --5-.46 -2,382                                   237          Zl"
                               iCheriton/Cape Charles 1             948         10-46              1     Z061  1                 540     1    1IS22      1


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                   This buildout has important implications for wastewater disposal impacts and future water supply
                   needs. Obviously, not every possible unit will be developed in the near future, however the buildout
                   assessment expresses the "blue print" that has been established for growth by both counties. If this
                   development were to occur, then significant water demands and wastewater disposal needs would have
                   to be addressed. For the combined total number of units of 37,677, a water demand of 5.65 MGD (37,677
                   units x 150 gallons per day) would be needed. As of 1990 only 1.2 MGD is supplied by public water
                   sources. Public water withdrawals would have to increase by over 4.5 times. Regarding wastewater
                   disposal, if all of these units were allowed to be built, then a total of 6.22 MGD of wastewater (37,677
                   units x 165 gallons per day) would have to be either treated and disposed to the ocean or Bay, or be
                   discharged to the ground water through septic systems. Further analysis of wastewater impacts under
                   buildout conditions is discussed in Section 8.

                   The numbers generated in the buildout were used in the nitrogen loading model to detern-dne maximum
                   nitrogen loading under the planned densities and land use types for both counties. The buildout numbers
                   for maximum number of units, agricultural areas, etc. are used to predict nitrogen loading under the
                   current land use plans, and to allow for scenario testing of different land use patterns.

                   This buildout analysis can be used as a predictive tool to help assess the impacts of future development
                   on the many community services that would be needed to support this level of development and to help
                   plan for changes in development densities and patterns of future development. In reality, the near
                   future will only see a fraction of this buildout potential due to market conditions and other factors.
                   Buildout analyses such as this one can be used to identify potential land use conflicts and to begin to
                   plan for changes to address these conflicts.




























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                                               Table 7-5: Developable Lot Analysis, Accomack and Northampton Counties

                               ACCOMACK COUNTY                                                                                       Measurements in acres
                                                                       jPermitted WPA @A@                                            Potential Potential
                                                                       Developable Undevel. Total                  Units/            Units       Units
                                         Land Use Type                        Acres        Acres       Acres       Acre              Dev. soils All soils
                               RR. Rural Residential                                  1      12           12          1              0           10       1
                               R-1: Residential
                               R-2. Residential
                               Trade                                                         60           60
                               Industry
                               Institutional
                               Parks & Recreation
                               Agriculture                                    161          3,183       3,344       15 acres          27

                               Total                                          161          32%         3,417                         27          579
                                                                       jPermitted WPA @B
                                                                                                                                     Potential Potential
                                                                       Developable Undevel. Total                  Units/            Units       Units
                                         Land Use Type                        Acres        Acres       Acres       Acre              Dev. soils All Soils
                               RR. Rural Residential                          733     1                   733         1              1623        623      1
                               R-1: Residential                                                                       3
                               R-2- Residential                               29                          29          2              50          50
                               Trade                                          626                         626
                               Industry                                       197                         187
                               Institutional                                  29                          29
                               Parks & Recreation
                               Agriculture                                    3,164          145       3309 11 /5 acres 1            538         363

                               Total                                          4,769          145       4,915                         11211       1,236
                                                                       Permitted WPA-C--7                             I Permitted WPA=

                                                                       Developable units/              Potential        Developable units/              Potential
                                         Land Use Type                        Acres          acre         Units                      Acres   acre         Units
                               RR;- Rural Residential                         1,220               1       1,037                      401         1        341
                               R-1: Residential                               2,985               3       7,612                      899         3        2,292
                               R-2- Residential                               205                 2       34F-                       312         2        sm
                               Trade                                          585
                               Industry                                       197                                                    71
                               Institutional                                  181                                                    10
                               Parks&Recreation                               0
                               Agriculture                                    3,726      1 /5 acres 1     633                        11811 1 /5 acres     308
                               Incorporated Town                              410                                                    8M
                                         residential                   3-10                       2       526-                       605         2        1,028
                                                 triade                       7                                                      14
                                            industrial                        72                                                     '40
                                         institutional                 r -22                                                         43

                               Totals by area                                 9,509                       10,157                     4,306                4,498
                               NORTHAMPTON COUNTY                      jPermitted WPAD                                [-Permitted WPA E                 I
                                                                       Developable units/              Potential        Developable units/              Potential
                                         I.and Use Type                       Acres          acre         Units                      Acres   acre         Units
                               Rural Resid. & Village Area                    628            2.178        1,163                      2,218   2-178        4,105
                               Urban Development Area                         2,394                                                  2,871
                                                   residential                1,836          2.178        3,998                      2,044   2.178        4,452
                                                 OCHrunercial                 151                                                    ill
                                                     industry                 96                                                     128
                                            roads/radroads                    2D6                                                    490
                                                       public                 170                                                    98
                               Agricultural or Forestral Area                 3,102     1         1    1 2,637:@                     5,707
                               Total by Area                                  6,125                       7,798                      10,7%                13AO9

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                                   NITROGEN LOADING
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                    SECTION 8: NITROGEN LOADING



                    INTRODUCTION

                    Nitrogen is present in surface and ground water environments in four primary forms. The forms are
                    organic nitrogen, ammonium-nitrogen, nitrite-nitrogen and nitrate-nitrogen. Organic nitrogen consists of
                    a variety of soluble, colloidal and particulate forms. Ammonium-nitrogen (NH4+) is characteristic of
                    poorly oxygenated (anaerobic) conditions and is readily adsorbed by soil particles in the unsaturated,
                    oxygenated zone above the water table where it is rapidly converted to nitrate-nitrogen. However,
                    ammonium-nitrogen may travel long distances in areas where the saturated zone is anaerobic.
                    Ammonium-nitrogen is the primary form of nitrogen in septic system effluent and in wetland soils.
                    Nitrite-nitrogen (NO2) is an unstable form which is rapidly transformed into nitrate-nitrogen, and so is
                    usually present in very small quantities. Nitrate-nitrogen (NO3) is characteristic of oxygenated
                    (aerobic) conditions and is highly mobile in ground water. In this form, nitrogen may travel long
                    distances with little attenuation. (Freeze and Cherry, 1979; Canter and Knox, 1986)
                    Nitrogen transformations are complex, bio-physio-chen-dcal processes. Figure 8-1 illustrates some of
                    the common nitrogen transformations, described below. The process by which organic nitrogen is
                    transformed to ammonium-nitrogen is called mineralization or ammonification, and occurs under both
                    aerobic and anaerobic conditions. The process whereby ammonium-nitrogen is transformed to nitrate-
                    nitrogen is called nitrification and occurs under aerobic conditions. Denitriftcation is the process by
                    which r-dtrate-nitrogen is converted to gaseous forms such as N2 and released to the atmosphere.
                    Denitrification occurs under anaerobic conditions, particularly within wetland soils. The opposite
                    transformation, whereby atmospheric nitrogen is converted to ammonium nitrogen is called nitrogen
                    fixation, and is performed by bacteria and blue-green algae (cyanobacteria). (Freeze and Cherry, 1979;
                    Canter and Knox, 1986)

                    NITROGEN AS A CONTANIINANT

                    Although all forms of nitrogen are critical components of natural systems, nitrogen can cause water
                    quality degradation if present in excessive quantities. In drinking water supplies, elevated nitrate-
                    nitrogen levels can cause an illness known as infant cyanosis, methemoglobinemia, or "blue-baby
                    syndrome" in infants, caused by the alteration of hemoglobin and subsequent problems with oxygen
                    transport. In addition, high nitrate-nitrogen levels have been linked to the formation of carcinogenic
                    nitrosan-dnes (Porter, 1978). To reduce potential health risks, the U.S. EPA has established a drinking
                    water standard of 10 milligrams per liter (mg/1) for nitrate-nitrogen. A statistical analysis of ground
                    water samples collected on Long Island, New York, demonstrated that when median nitrate-nitrogen
                    concentrations were 6 mg/l, 10 percent of the samples exceeded the 10 mg/l drinking water standard
                    (Porter, 1978). To account for this variability, the Cape Cod Planning and Economic Development
                    Commission (CCPEDC) and several towns across the state of Massachusetts have adopted a more
                    conservative concentration of 5 mg/l, as a planning guideline. ne Virginia State Water Control Board
                    adopted a ground water standard of 5 mg/I for nitrate-nitrogen in the early 1970's. Since then, the anti-
                    degradation policy supersedes these standards. In the case of Virginia, the numeric limits are meant as
                    guidance and are for permitted discharge. The ground water standards are different and separate from
                    drinking water standards, and are not levels that have to be reached should a clean-up be necessary. (T.
                    Wagner, SWCB, personal communication, 1991).





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                                                                    Figure 8-1: Nitrogen Transfomiations




                                                                                     Precokation

                                                                                                 f WH-!l
                                                                              INOil              IN031

                                                                                       Mineral                          Plant Residue,
                                                 Sewage                                Fwffim                              Compost
                                               Organic - N                               NH -3                            Organic - N
                                                    NH3                                  N03                                Proteins



                             N L                                       NH 3                        N Z

                                                                                                            Wrogen Fixatim


                                            Decomposition                            Nitrification
                                              Nitrifiication           N@Hj-                              Proteins          Decomposition
                                                                      F                                                                4
                         Denkrification                 NH"                                         Denitri                        NHq                Denitrification
                                                            q

                                                                   A;;p@fion                   F       Adsorption               Nitrification


                                                 N03                                   N03                                          NOj


                                                                                     Leaching


                                                                       - - - - - - - - - - - - - - - - - - - - --


                                                                          Ground Water            N0j             Ground Water            NOj
              - - - - - - - - ---



                                                                        (Denitrification in Reducing Zones)                                        N zO]
                                                                                                                                         FN L@ F
                                                                                                           fication
                                                                                                                                                             1P



                                                @NOj






                       Adapted from Freeze and Cherry, 1979.


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                     SOURCES OF NrrROGEN

                     Nitrogen originates from a variety of natural and anthropogenic sources, including sewage, fertilizers
                     (residential and agricultural), road runoff, precipitation, landfills, and wildlife. A discussion of
                     published loading rates for these various sources is provided below.

                     Sewage
                     Sewage-derived nitrogen may be produced by a variety of sources, including sewage treatment plants,
                     septage lagoons, on-site sewage disposal systems, exfiltration from leaking sewer mains and combined
                     sewer overflows (CSO's). On the Eastern Shore, on-site sewage disposal systems are the primary source
                     of nitrogen to the ground water.
                     The quantity of nitrogen produced by a given on-site sewage disposal system is a function of the volume
                     and concentration of the effluent discharged, which, in turn, is dependent on the per capita water usage
                     and the occupancy rate. Daily rates of water use may range from 36 to 150 gallons per person per day
                     (EPA, 1980; Nelson et al., 1988) with average rates on the order of 50 to 75 gallons per day (gpd). In
                     estimating sewage flow rates, however, it is important to differentiate between the amount of water
                     actually used and the amount ultimately discharged to ground water as sewage flow. Typically, 20% of
                     the water used may be lost through evaporation or transpiration during irrigation and other outside
                     uses (Nelson et al., 1988). For the purpose of this study, a ground water discharge rate of 55 gpd per
                     capita was used for sewage flow.
                     Quantification of household populations is very difficult, particularly in seasonal communities such as
                     the Eastern Shore, where summer populations may be significantly higher than winter populations.
                     For the purpose of this investigation, an average annual occupancy rate of three people per household
                     was used, based on average occupancy rates as determined for Northampton County. However, a
                     sensitivity analysis was conducted to evaluate household populations ranging from two to four people.
                     A review of the literature indicates that nitrogen concentrations in raw sewage may range from 20 to 100
                     mg/l. Once sewage enters a properly functioning septic system, however, some removal of this nitrogen
                     occurs both within the septic tank and in the soils below the leaching area. Studies have indicated
                     that between 30 to 60% of the nitrogen may be removed in this way (Porter, 1978; Andreoli et al., 1979).
                     Thus, in estimating loading rates from on-site sewage disposal systems, it is important to use nitrogen
                     concentrations in effluent discharging from the leaching area. Data on total nitrogen concentrations in
                     effluent sampled either from the leaching area or from ground water immediately below the leaching
                     area are summarized in Table 8-1.


                                         Table 8-1: Total Nitrogen Concentrations in Septic System Effluent

                                      Souroe                                                        Concentration
                                      Bourna et al., 1972                                               30 mg/l
                                      Walker et al., 1973                                               40 mg/l
                                      Dudley and Stevenson, 1973                                        14 mg/l
                                      Magdoff, 1974                                                     31 mg/l
                                      Magdoff, 1974                                                     41 mg/l
                                      Reneau,1977                                                       23 nig/l
                                      Brown and Assoc, 1980 (summary)                                   37 mg/l
                                      Ellis, 1982                                                       34 mg/l
                                      Canter and Knox, 1986 (summary)                                   40 mg/l
                                      Nelson et al., 1988 (summgj)@)                                    34 mg/l


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                   A critical review of these reports, particularly the more recent ones, suggests that an average effluent
                   concentration of 40 mg/I is a conservative yet defensible value to use in evaluating water quality
                   impacts of on-site sewage disposal. This value was used in our analyses. Using a flow rate of 55
                   gallons /capita /day and an average effluent concentration of 40 mg total nitrogen/I, the average
                   loading rate per capita is 6.72 lbs N/year.

                   Fertilizers

                   Agricultural fertilizers are usually the primary nitrogen source to ground water in heavily farmed
                   areas. Accomack and Northampton Counties are predominantly agricultural, with land in farms
                   accounting for approximately 53% of the total land area. In Accomack County, poultry production is the
                   main industry. The predon-dnant crop grown in the two counties is soybeans, a plant which is a nitrogen-
                   fixer and so does not require nitrogen fertilization. The remaining acreage of crop land requires a
                   significant amount of fertilizer (see Table 3-5). For Accomack County this averages 89 lbs/acre and in
                   Northampton County the average agricultural nitrogen application is 79 lbs/acre.

                   Fertilizer and manure applications and poultry production may contribute large quantities of nitrogen to
                   the underlying aquifer depending upon the agricultural management practices in use. The application,
                   production, and storage of fertilizers and animal wastes result in the most important nitrogen
                   contributions.

                   From the Cooperative Extension Agents in both counties, information was gathered regarding crop type
                   acreage and fertilizer application rates. This was used to calculate an average fertilizer application
                   rate of 84 lbs N/acre/year, for all agricultural areas in both counties. An average leaching rate of 25%
                   was assumed for farm fertilizers. Many researchers have documented nitrogen leaching rates that
                   range from 1%47%( Ritter, and Manger,1985; Bouk, 1984; Bacon, 1989; Bower, 1989; Owens, 1987; and
                   Hubbard, 1986). Nitrogen leaching rates to ground water can be affected by many factors including: crop
                   type, application rates, irrigation, soil types, application timing, fertilizer formulations, and climate.
                   As such, the literature shows a wide range of nitrogen loading values. The value of 25% was chosen
                   since it represents a value most often selected in modelling studies of nitrogen movement, and also
                   because it represents a mid range of the values from the literature.

                   Animal Wastes


                   Given the high levels of organic and ammonium-nitrogen in manure, animal waste may function as both
                   point and non-point sources of nitrogen contamination. Chicken manure, in particular, has a high
                   nitrogen availability rate, making it easily leachable into ground water.

                   If wastes are produced or stored on open ground at poultry houses, rainwater can transport nitrogen by
                   percolation through the wastes and into the soil and ground water. All poultry waste is assumed to be
                   used as agricultural fertilizer for the purpose of this study. Prior to application as fertilizer, most
                   manure remains in the poultry houses until it is cleaned out once or twice per year (J. Belote, personal
                   communication, 1991). Storage of poultry wastes is usually thought to be a source of nutrients and
                   pathogens that contaminate ground water. For this reason, on the Eastern Shore in Maryland, efforts
                   are being made to construct storage sheds for poultry manure, rather than continue the current practice of
                   letting manure pile up uncovered outside.

                   Natural mortality accounts for many tons of dead poultry birds. As explained in Section 3, the practice
                   on the Eastern Shore of Virginia is to either bury or compost the chickens. The majority of chickens
                   which die before being sent to the processing plant die within the first two weeks of life, and it is
                   estimated that given the 1990 population, a total of 1.8 n-dIlion pounds of dead birds had to be



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                    disposed. At 3.3% nitrogen (Keeton, 1980), dead chickens contributed 60,638 pounds of nitrogen to
                    Accomack County in 1990.

                    Lawn Fertilizers

                    Fertilizers applied to residential lawns and golf courses contribute nitrogen to ground and surface
                    waters. The pathway may be either direct, via surface runoff, or indirect, via gradual leaching to
                    ground water. The amount of fertilizer that ultimately leaches into ground water is a function of the
                    type of ground cover, soil characteristics, climate, type of fertilizer used, application rate, and the
                    degree of irrigation /rainfall. A literature review of experiments conducted primarily on turf plots
                    suggests that leaching rates may vary from less than 1% to 80%, depending on site specific conditions
                    (see Table 8-2). Leaching rates rarely exceeded 30%, however, unless extremely high fertilization and
                    irrigation rates were used (e.g. Nelson et al., 1980).


                                         Table 8-2: Leaching Rates for Fertilizers Applied to Turf Areas

                                           Reference                                        % Leached

                                           Brown, 1977                                          2-27%
                                           Brown, 1982                                          1-18%
                                           Chichester, 1977                                     1-8%
                                           Dowdell and Webster, 1980                            2-5%
                                           Hesketh, 1986                                        0-31%
                                           Mancino, 1980                                        04%
                                           Morton, 1988                                         2-14%
                                           Nelson, 1980                                         5-81%
                                           Petrovic, 1988                                       0-17%
                                           Starr and DeRoo, 1981                              4%

                    Based on a review of this data, with particular emphasis on regional similarities, a leaching rate of
                    30% was selected as a conservative (worst case) average value for nitrogen applied as fertilizer to
                    residential lawns within the study area.
                    The typical lawn size for a given lot will vary widely depending on overall lot size, residential
                    character, and individual preferences. Few quantitative studies have been conducted of average lawn
                    sizes. The Long Island, New York and the Barnstable County, Massachusetts 208 studies both used an
                    average lawn area of 5,000 square feet. More recently, a survey conducted as part of the Yarmouth
                    Water Resources Protection Plan documented an average lawn size of 4,350 square feet on half acre lots
                    (Nelson et al., 1988). There have been no known studies on the Eastern Shore of Virginia regarding
                    lawn sizes and application rates of fertilizers. For this study, an average lawn size of 5,000 square feet
                    was used.

                    Fertilizer application rates are similarly difficult to quantify. The Cape Cod and Long Island 208
                    studies used an average annual application rate of three pounds per 1,000 square feet. The Yarmouth
                    survey documented a similar annual application rate for homeowners (2.8 lbs/1,000 sq. ft.) and a higher
                    annual application rate for professional lawn maintenance companies (4.7 lbs/1,000 sq. ft.). For this
                    study, an average annual application rate of 3 lbs/1,000 sq. ft., equivalent to 39 lbs N/acre, and a
                    leaching rate of 30% was used. Although lawn fertilization is not a widespread practice on the Eastern
                    Shore of Virginia, these studies are the only means of taking into account any turf maintenance.




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                  Landfills

                  Unlined landfills contribute large quantities of nitrogen to ground water through the decomposition of
                  buried organic matter. Nitrogen loading from landfills was based on nitrogen concentrations in typical
                  leachate, 218 mg/I (Patrick and Quarles, 1983). The area of the landfills was obtained from the
                  Accomack-Northampton Planning District Comn-dssion, and an annual recharge rate of 24 inches per
                  year was used (no vegetation/ transpiration). This yielded a loading rate of 1184 lbs N/acre/year for
                  landfills.


                  Septage Lagoons
                  Three septage lagoons are located on the Eastern Shore. These lagoons primarily receive the contents of
                  septic tanks, pumped out according to proper maintenance procedures.
                  The nitrogen loading to ground water from septage lagoons is a product of the raw sewage load minus
                  the amount attenuated in the septic tank, gaseous losses from the lagoon, and attenuation in the soil
                  during percolation from the lagoon. The nitrogen concentration in raw sewage can vary from 20 to 100
                  mg/I (Metcalf & Eddy, 1979; Laak, 1980; Douglas, 1986), but the total load depends on the associated
                  sewage flow. Nitrogen loads in untreated waste water have been reported from 8 to 13 lb/capita/year
                  (Porter, 1978; Brandes, 1978; Laak, 1980; Camp and Meserve, 1974). Porter (1978) summarized a number
                  of studies which found an average septic tank influent concentration of 65 mg/l, an average septic tank
                  effluent concentration of 45 mg/l and an average removal of 31%.

                  Additional reduction occurs from gaseous losses from the lagoon and during percolation of septage into
                  the soil. The estimated nitrogen concentration of septage reaching ground water can conservatively be
                  set at 45 mg/l.

                  Pavement and Roof Runoff

                  Sources of nitrogen in pavement runoff include precipitation, soil erosion, leaf litter, street dirt,
                  garbage, and animal waste. Nitrogen concentrations in road runoff can vary by an order of magnitude,
                  depending on spacing between storms, the intensity and duration of a storm, and the tin-dng of sample
                  collection. The highest nutrient concentrations are generally found in the "first flush". A summary of
                  typical road runoff values published in the literature is provided below:


                                         Table 8-3: Total Nitrogen Concentrations in Road Runoff

                                  Reference                        Total Nitrogen Concentration

                                  Koppelman, 1982                        1.49 mg/l
                                  Howie and Waller, 1986                 1.13-2.15 mg/I
                                  Lager et al., 1968                     3-10 mg/I
                                  Loehr, 1973                            3 mg/I
                                  Schn-ddt and Spencer, 1986             2.04 mg/I
                                  Valiela and Costa, 1988                0.38 mg/l (27 um)*
                                  *Dissolved Inorganic Nitrogen only

                  For the purposes of this analysis, a nitrogen concentration of 2.0 mg/I in road runoff was used. For roof-
                  runoff, a nitrogen concentration of 0.75 mg/I was selected (Nelson et al., 1988).




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                                                                  8-6









                    ESTIMATION OF PAVED AREA/ROOF AREA

                    HWH estimated the total paved road area to be 15% of all land area (Nelson et al., 1988), multiplied
                    by 55% since a typical 40 foot right of way includes a 22 foot width of actual pavement.

                    Driveway surface area was estimated to be 500 square feet and roof area to be 1500 square feet per
                    residential unit (Nelson et al., 1988).


                    Businesses/Industrial/InstitutionaI

                    The nitrogen loading from business, industrial, and institutional facilities was calculated to average
                    the design sewage flow per acre for all current land uses in these areas. From the community, non-
                    community, and non-transient non-community water supply list, population information was obtained
                    for the number of persons served in motels, restaurants, campgrounds, trailer parks, hospitals, and
                    nursing homes, as well as the number of employees working in offices and the number of students
                    attending the schools. These data were then totaled per category and multiplied by the design flow
                    per person, employee, or student, as estimated by the Virginia Water Control Board. From this, the
                    total sewage flow for business, industrial, and institutional areas was obtained for each of the two
                    counties. This number was divided by the number of acres currently under these land uses to obtain an
                    average sewage flow of 423 gal/acre/day. The assumption was made that the sewage from these uses
                    has a similar nitrogen concentration (40 mg/1) to residential sewage.

                    Precipitation

                    Nitrogen concentrations in precipitation vary regionally. As precipitation falls on vegetated areas
                    much of the dissolved nitrogen is taken up by vegetative cover and within the root zone, and thus does
                    not leach into the underlying aquifer. Based upon scientific literature, natural background levels on
                    nitrate-nitrogen in ground water are typically 0.05 mg/l or less. This value was used in our analysis as a
                    representation of natural background conditions.


                    NITROGEN LOADING ANALYSIS

                    The nitrogen loading rates used in our analyses were selected on the basis of the literature review
                    outlined above, and also to correspond with a recently calibrated nitrogen loading model developed for
                    the Town of Yarmouth, Massachusetts (Nelson et al., 1988). The loading rates for sewage and
                    fertilizers originally used in this model have been slightly adjusted to reflect recent findings, which
                    suggest that loading from on-site sewage disposal systems may be higher and loading from lawn
                    fertilizers may be lower than previously thought. The loading rates used in our analysis are
                    summarized in Table 84 below.

                    Once nitrogen has entered the ground water system, ultimate nitrate-nitrogen concentrations can be
                    calculated using a simple mass balance equation, in which nitrogen levels are a function of the annual
                    rate of nitrogen loading and the annual rate of dilution through recharge. Sources of recharge to ground
                    water include precipitation, surface runoff from impervious areas and artificial recharge from on-site
                    sewage disposal. Recharge rates used in the nitrogen loading analysis are summarized in Table 84.
                    The nitrogen loading under existing conditions is presented in Tables 8-5 and 8-6.






                         Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                     8-7








                                                       Table 84: Nitrogen Loading Values

                   Source                     Concentration            Laading Rate               Flow/Recharge
                   Sewage                       40 mg N/liter        (6.72 lbs N/Person-yr)     55 gallons/ person-day
                                                                                                (165 gal/dwelling)
                   Business /Industrial/        40mg/I                                            423 gal/lot
                      Institutional
                   Fertilizer (Lawns)                                (0.9 lbs N/1000 sq ft-yr)    17inches/year

                   Fertilizer (Agriculture)                          84 lbs, N/acre-yr, avg.      17inches/year

                   Pavement Runoff              2.0 mg N/liter       (0.42 lbs N/1000 sq ft-yr)   34 inches/year

                   Roof Runoff                  0.75 mg N/liter      (0-15 lbs N/1000 sq ft-yr)   34 inches/year

                   Landfills                                         1184 lbs N/acre-yr           24 inches/year

                   Septage Lagoons              45 mg/l

                   Precipitation                0.05 mg/I                                         17 inches/year
                   Source: Adapted from Nelson et al., 1988


                   NITROGEN MODELLING RESULTS

                   Tables 8-5 and 8-6 present the results of the nitrogen loading model used by HWH to predict nitrogen
                   concentrations in the ground water as a result of existing land use activities. The tables show that for
                   Accomack, the total nitrogen from all sources is expected to result in a ground water concentration of 2.0
                   mg/l N. The results for Northampton show a similar average concentration of 1.9 mg/I N. These results
                   represent an average nitrogen concentration across the entire county and do not reflect nitrogen
                   concentrations at any specific location in the study area.

                   In Accomack County the majority of the loading of nitrogen is from agriculture (1,055,095 lbs per year).
                   Septic system loading is the second highest source of nitrogen reaching the ground water. These
                   findings reveal that on the average, across the entire county the nitrogen concentrations in the shallow
                   ground water are acceptable. What the analysis does not reveal is that in order for the average
                   conditions to reach 2 mg/I of nitrogen that there are many areas that will have significantly higher
                   ground water nitrogen values.

                   Northampton County results show that the same categories of nitrogen inputs are contributors to the
                   overall concentration of nitrogen in the ground water, however there are no septage lagoon and animal
                   burial inputs. Even though the total nitrogen load in Northampton County is lower than in Accomack
                   County (406,258 vs. 1,055,095 lbs/year) the resulting final recharge nitrogen loading concentration is
                   approximately because the total recharge to the ground water is lower in Northampton County.

                   The results show that based on existing land use conditions, nitrogen concentrations in the shallow
                   ground water are on the average acceptable and within state and local drinking water standards.
                   These results are compared with existing water quality testing in the next section.






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                                                                                         Table 6-3c Mirage& LeedLng CAlcukidow, Accomack Exind,

                                                INFUTFACTORS
                                                Number of Rmdefdial VDAft                                                   L%340

                                                Sawrapfloorperhouse(PI/day)                                                 165

                                                CommercLaWndw-rial lead (acme) 1                                            3,701

                                                CAmalawl. arvoup flow Per acre           1                                  423
                                                (gal/day)
                                                N@insewapeffinam(negil)                  1                                  40

                                                Learn am Per I               faclame few 1                                  5.000

                                                Favemmuperhaventaquaraled)               I                                  sw

                                                Rand am (aclume fmo                                                    1x6K000

                                                Read arm per hama, ( I         few                                          IAN

                                                Agricultural am (acres)                                                     47,4"__
                                                [thaaa acres &4* are forwizedl
                                                Lawfins taalw

                                                SaPtaffe I%- (Pumue"

                                                Sep"I N cuumn&wdue OM&ID                                                    43

                                                .4-1-1 be" Me 4T)                                                           %07,M

                                                ToW re&aW am (acreg                                                         L%.Uq

                                                RiecharV rwa for "mom                                                       V
                                                am (in"?
                                                RC&MV met for unparvious                                                                       7777=
                                                area (in"

                                                                INPUT                                              CALCULATIONS                                                RMULTS

                                                         Sew.1te (SaUday)                                                                                 CALCULATED LOADING (LB&M
                                                               3,929,1"                      x N-ccnc(mg/l) x 3.7851/0 x 3&Sdavs/vr: 4540DO mRAb

                                                          Laam area (ag ft)
                                                              79AW.000                                             x OA009 lb N log ft
                                                                                                applicad     rate 3 lb/1000 sq ft x 30% leaching rate
                                                       Pavement areei (Bg fo
                                                              135,601000                                          x O.ODD42 1b N /mg ft                                          SIL212

                                                          Rwf me (ag ft)
                                                             -2.3,760,000                                          xCL0D0IS1bN/wqft

                                                        Natural area (&a
                                                                -177,478                                x 43%0 q ft/ame . OLOODDOS 1b N /*q ft                                   311.635

                                                           Other Sma'"s
                                                        Ariculture (acrew)
                                                                 47,420                               x 89 The N/acre/year x 25% lead%int rate

                                                          Landfills (acme)
                                                                 us                                              1184 11*N/acre/ywar                                            I48,0w

                                                    Septag, Lalowu (ItaLoya"I
                                                               1,170,0w                                N-ccmc (mA/1) x 3."S 1 /gal: 454000 mg/lb

                                                     Animal burial (Ibelyear)
                                                                                                                x 33 % N cancentratim                                            GOAM

                                                                                                                 TOTAL NITROGEN IDA DING 1 L&SIYR)                             1.914-M
                                                techarp from ww/w me Otallds                                                                                      TOTAL RECHARGE (MGfM
                                                               3.929,323                              x 36S dayB/yr: 1,000,ODO gal/trullian gal                                 -1.435

                                                    Total perims me taq ft)
                                                            91936-%Kmo                     X171ntyr/izin/ftx7.48gal/cuft:I,WD=gal/nWliongaJ
                                                   To"Am -,.=Oq N                          x34tn/yr /12in/ftx7.48 ital/cuft: LRF-WDW/millian gal                                 5.149
                                                             24Z967,7W
                                                          Landfills (eq f0                                   /fix 7.48 RaJ/cv ft: 1.605.0%) W/miWan gal                           81
                                                               5,445,0W                                                     TOTAL RECHARCE (MCAUYR)                             nxi"
                                                TOTAL NITROGEN LOADITUTAL RECHARGE X 451,000 MC/LB: 3,785,000 L/ MCAL
                                                                                         I PEOiARCENffROGENCONCENTRAnoN(vtg4wppuUI                                                2-0

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                                                 Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                                                                                        8-9






                                            INFUTFACTORS                            TaMe       Ni- g Loscling CAlculatimm NordL&oq*on ExIod"
                                                    of Ravideadd wAts                                                    6,IB3

                                            Sewage flow par havan (Balfday)                                              W

                                            cowarmuntainswumerid lavad facraml 1                                         960

                                            CAn64tmL savrap flow per wra            1                                    423

                                            N4xw- in --w        efflumt tang1l)     1                                    40

                                            Lawn am Pair house (square imb          I                                    S,000
                                            Famnsitt Pair havot (SROM fee"          I                                    Sao           777=
                                            ROW ax,am (Npuww low                    r-                         109,11i'm
                                            Rood aram Par house (square ind         I                                    I'm           777=

                                            A$ncmltwW area (acreal                                                       20,S70
                                            Idloon savis dud am fardli"
                                            I ,Afill, (&CreW                                                             75
                                            Septep Iw- (PlIcats"                                                         0       77777=

                                            Septage N conciamaidw tvngn)            1                                    45

                                            Aninial ba" Obs tyr)                                                         0
                                            Total rodumSe am (&a4W                                                       94"7    77@Z
                                            Rachm" rave ft pervious                                                      17            - - -
                                            am (Lo0yr)

                                            PAwhwp mat for unpervious                                                    34
                                            ana UrJyr)

                                                            INPUT                                            CALCULATIONS                                             RESULTS
                                                     Sewage (gal/day)                                                                             CALCULATED LOADING (LBSPYR)
                                                           1,267,915                    XN-cmc(mg/I)x @851/Wx@365davv/yr:454=tng/lb                                      142.147

                                                      Lawn was (eq Ill
                                                           30,915,ODD                                       x ODOM lb N /ag it                                           27,U4
                                                                                           applicAmon rate 3 lb/1000 sq ft x 30% ltaddng rate

                                                          1=209,300                                          .0.000421bN/aqft                                            47,1n

                                                      Roof arta (ag tt)
                                                           9=4,SW                                            xQ01001S1bN/aqft

                                                    -Natural area (acr.W
                                                             6913"                                x@eqft/aaex Q00000SIbN/agh                                             15,107

                                                        Other SMINIM
                                                     Algriculture (wes?
                                                             2U70                   -x 79 lbs N/aae x 25% leachinIt rate                                                 406,2m

                                                      Landhila (acres)
                                                                78                                         1184 The N /Kre/year                                          12 -m

                                                Septage LmSoom (galtyeas)
                                                                0                               x N-aDw(mg/1) x 3MI/gal:4SWWmjt/lb                                        0

                                                  AnwW burial flbw@mw) _
                                                                0                                         x 3.3 % N cancmirsuan                                           0

                                                                                                            TOTAL NITROCER -LOADING ILBSIYR)                             73Z206
                                                                                                                                                          TcyrALRECHARCE(MWM-
                                            techam hvm                ptage (ftaL/dav)
                                                           1,167,815                             x 365 doys/yr: LOW.= gal/vullion A&I                                    426

                                                        P-- - (.q ft)
                                                         3,968,73"W                   x 17 Wyr /12 irk/ft x 7.48 gal /Cu ft: I'Maw                                       4LO56

                                                Total unpemous was (ag it)
                                                     Without Landfilts                x34tn/vr /121n/ftx7.48 gal/cu ft: 1,000,WD                                         4009
                                                          141.957,000
                                                       Landfills (*9 ft)              x 24 in/yr /12 in/ft; 7.48 gal /cu ft: I,W0.0W
                                                            3@W,680
                                                                                                                         TOTAL RECIiARGE (MCAUYR)
                                            TOTALNrMOCEN LOAD/70TAL RECHARGE X 454,000 MG/L5: 3,76b,MU Ll MGAL
                                                                                    I -RECHARGE NITROGEN CONCENTRATION fv*l or

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                                              Ground W                ater Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                                                                                 8-10









                     E)(ISTING WATER QUALITY TESTING RESULTS

                     The following section summarizes four studies or data bases which include test results for nitrogen
                     content. These sources were researched in order to determine the extent of nitrate-nitrogen present in
                     wells The majority of wells sampled, show low nitrate concentrations, although several results show
                     very high nitrogen values that are probably related to a specific high nitrogen loading source.

                     Virginia Department of Health, Public Water System Inventory

                     The Virginia Department of Health tests public water supply wells regularly for several contaminants.
                     The facilities included in this inventory fall under the categories of community, non-community, and
                     non-transient non-community water supplies. Sample analysis dates generally fall within the years
                     1988 to 1990. The Table 8-7 is a synopsis of the information obtained from the VDH data base.

                     In general, the nitrate concentrations from these samples are low, especially in Northampton County.
                     In Accomack County, three facilities had samples which tested above 5 mg/l. Four readings taken for a
                     Town of Parksley well had nitrate nitrogen levels of 6.6, 6.9, 5.65, and 6.2 mg/l. A NASA facility,
                     Charles G. Ward Building F-16, registered the highest nitrate levels of the testing group. Eight
                     samples from that facility ranged between 7.27 and 11.5 mg/l. Finally, a well at Stoney Point Decoys
                     was measured to have a nitrate nitrogen concentration of 7.11 mg/l. Most of these wells draw water
                     from the deeper confined aquifer where nitrogen concentrations are expected to be very low. The higher
                     readings reflected in this data base are probably the result of influences from the shallow aquifer
                     system.



                                     Table 8 -7: Virginia Department of Health Public Water Test Results
                        Average Nitrate-             Accomack CQmnly                 Northampton CouM
                        Nitrogen concentration               1.27 mg/I                       0.04 mg/I

                        Range, Nitrate-                      0.01-11.5 mg/l                  0.01-1.63 mg/l
                        Nitrogen concentration

                        Number of samples                    92                              31

                        Number of facilities                 24                              11


                        Number of samples
                        above 5.0 mg/I N03                   13                              0

                        Number of samples
                        above 10.0 mg/I N03                  3                               0



                     State Water Control Board, EPA STORET Database

                     The EPA maintains a database which contains a summary of ground water test results for public water
                     supplies. This information is available to all states. Due to budget limitations, recent data has not
                     been entered into the system, and the available information includes results from the late 1970's to late


                         Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                    8-11








                    1980's. Again, nitrate-nitrogen levels were low on average. Out of approximately 500 wells in
                    Accomack and 150 in Northampton, only seven (7) wells reported nitrate-nitrogen levels above 5.00
                    mg/l. Table 8-8 summarizes results for the wells which tested high.
                    Most wells which tested high for nitrate-nitrogen are shallow; therefore they draw water from the
                    unconfined Columbia aquifer. The one exception is the town of Parksley Well #1, which has a screen
                    depth of 160 feet. In the Virginia Department of Health database, as described above, Parksley also
                    reported high nitrate-nitrogen levels. The results from these two sources may be cause for further
                    investigation into the quality of the drinking water supply for the town of Parksley.
                    Observation Well #103A is located on Church Neck, an area devoted mainly to agricultural practices
                    (as delineated in the Northampton County Comprehensive Plan, 1990). The high nitrate levels here
                    may indicate a correlation between fertilizer use and elevated nitrate-nitrogen levels in the ground
                    water. However, the majority of wells in the two counties showed no contamination and it is likely
                    that many were likewise located in agricultural areas.

                                     Table 8-8: Nitrate-Nitrogen Levels Above 5 mg/I in STORET (EPA) File,
                                                      Accomack and Northampton Counties
                        Facility                     Date sampled             Nitrate -nitrogen        Screen Depth
                        Accomack County                                       level (mg/1)             (Feet)
                        Town of                      6/27/77                  8.00                     160
                        Parksley #1                  11/14/77                 6.50
                                                     2/23/78                  6.00

                        Town of                      12/9/74                  8.50                     64
                        Parksley #2

                        Observation                  2/13/80                  9.50                     40,30,40
                        Well #114S                   2/13/80                  10.00
                                                     2/13/80                  10-00
                                                     7/9/84                   7.00

                        Atlantic Fire                8/4/81                   5.00                     69,63,69
                        House


                        Northampton County
                        Observation                  9/28/77                  13.00                    40,27,37
                        Well #103A                   9/28/77                  11.00
                                                     5/11/79                  17.60
                                                     6/26/84                  24.00

                        Observation                  10/3/77                  6.90                     36,26,36
                        Well #104S                   10/3/77                  6.90
                                                     8/18/80                  7.50
                                                     8/19/80                  9.00
                                                     8/4/86                   8.25

                        Brown &Root                  12/1/77                  17.00                    20,40
                        S710-5




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                                                                    8-12









                     Virginia Department of Health, Eastern Shore Health District

                     The Eastern Shore Health District conducted a shallow well baseline monitoring project in April of
                     1990. The testing was done in response to studies completed by the United States Geological Survey
                     which indicate that wells installed at shallow depths may be at risk of having high levels of nitrates
                     and pesticides. The Health Department intends to confirm or deny these results, and if necessary,
                     change regulations to prohibit the use of water supplies proven to be at risk.

                     The written report of the baseline study is not yet available. Lab results were obtained, and are
                     summarized below in Table 8-9. Present information available does not include the location of sampling
                     sites. Twelve samples were taken in Accomack County, and ten in Northampton County. Wells
                     sampled were domestic drinking wells drilled to a depth of 30 to 50 feet.



                                   Table 8-9: Eastern Shore Health District,  Shallow Well Monitoring Results

                                             Accomack County                          Northampton CounW
                         Average
                         Nitrate-nitrogen
                         concentration                1.11 mg/l                                4.36 mg/l

                         Number of
                         samples                      12                                       10

                         Number of samples
                         above 5.0 mg/l N03           1                                        4

                         Number of samples
                         above 10.0 mg1l N03          0                                        2


                     Average concentrations for nitrate nitrogen were much higher in Northampton County in this study
                     than in the deeper wells in the county tested by the state. Although the sample size was small for this
                     monitoring project, some of the levels of nitrogen were high, and the test should serve as a warning for
                     residents with wells dug in the shallow aquifer. With knowledge of the locations of these sites, origins
                     of the nitrate-nitrogen (agriculture, septic tanks, etc.) could be better determined and assessed. Two
                     types of pesticides, triazines and carbanates, were tested, and none were detected in the 22 samples.

                     A baseline study of deeper wells was also conducted by the Eastern Shore Health District. At the time
                     of publication of this report, no information about the baseline study has been made available. This
                     Ground Water Management and Protection Plan is primarily concerned with large withdrawals from
                     and preservation of the deeper Yorktown-Eastover aquifer. However, studies of the kind that the
                     Eastern Shore Health District has conducted are invaluable as documentation for future use and for the
                     determination of present contamination which may reach the lower aquifers at a later date.

                     USGS Water Quality Sampling

                     The United States Geological Survey is currently involved in a water quality study of shallow wells on
                     the Delmarva Peninsula as a continuation of a water quality analysis through 1987 (USGS Open File
                     Report 89-34). Table 8-10 presents the unpublished results of nitrate-nitrogen levels along two
                     transects, and isolated locations along the mainland. Samples have been taken from August 1988 to


                          Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                     8-13








                                                                                         Table 8-10- USGS Nitrogen Sampling

                                                                   Sample                Sample                Sample              Sample                Sample               Sample
                        ID           Lai        LwM Depth Date-1               N03-N Date-2 N03-N Date-3                 N03-N Dale-4 N03-N Date-5                  N03-N Date-6 N03-N
                        Creek-Up        371151    755725       0.0                                                                                          Jun-90      4.70
                        Creek-Dn        371147    755700       0.0                                                                                          Jun-90      5.30    Nov-90        4.80
                        Well 1          3711451   755659       6.61                                                                                         Jun-90     14.00,   Nov-90       13.00
                        Well 2          371143    755658       8.9                                                                                          Jun-90      6.601   Nov-90       13.00
                        Well 4A         371125    755702       16.8   Aug-88        9.70 Dec-88        10.00     Jun-89       9.60
                        Well 4B         371125    755702       26.0   Aug-88        9.60                         Jun-89       9.20                                              Nov-90        9.60
                        Well 4C         371125    755702       41.5   Au-g--881     9.20                                                                                        Nov-901       7.10
                        Well 4D      1  371125    755702       61.5   Aug-881       0.37                         Jun-89                                                         Nov-90        0.10
                        Well 4E         371125    755702       16.8                                                                                                             Nov-90       19.00
                                                                                                                                                                                Nov-90        6.20
                        Well SA         371121    755650       9.@    Aug-88        8.90  Dec-88       10.00     Jun-89       8.901
                        Well 5B         371121    755650       28.0   Aug-88      31.00                                                                                         Nov-90       10.00.
                        Well 6          371128,   755721       15.0                       Dec-88       34.00     Jun-89      29.00
                        Well 7A         371136    755802       12.0   Aug-88        9.10  Dec-88.         9.40   Jun-89      15.00
                        Well 7B         371136    755802       31.0   Aug-881       3.50                         Jun-89       2.60
                        Well 8          371136    755748       12.0            1          Dec-881      18.00
                        Well 11      1  371301    755844       13.0   Aug-88      12.00                                              Aug-89         7.80
                        Well 12         3713021   755832       13.0   Aug-88      38.00
                        Well 13         3711181   755635       6.6    Aug-88        0.10  Dec-88         0.151   Jun-89       0.10
                ,a      Well 14         371117    755631       6.7,   Aug-88        0.10
                E,
                N       AC 201D         375744    753536       42.0                                                                  Sep-89              -
                        AC 204S         375535    753249       22.5                                                                  Sep-89         0.13
                        AC 204D         375535    753249       48.5                                                                  Sep-89         0.10
                        AC 205S         375552,   753018       22.0                                                                  Sep-89         9.60
                                                  753444       36.0                                                                    Jan-90       0
                        SOW 110S        3757231                                                                                                        .10
                        P32 D           373049    7.54841      30.0   Aug-88      11.00
                        P32 S           373049    754841       22.0   Aug-88        9.20
                        P31 D           373330    754946       40.0   Aug-88        0.10@
                        P31 S           373330    754946       13.0   Aug-88.     15.00
                        P31AD           373916,   754108       30.0   Aug-881       6.20
                        P31AS           3739161   754108       13.2   Aug-88        8.10
                02.     P30 D           3747551   753710       28.0   Aug-88        0.10
                                                                      Au -88
                        P30 S           3747551   7537101      15.0 in              0.291








                       November 1990. The depth of the wells range from 6.6 to 61.5 feet. Nitrate-nitrogen levels are
                       generally high. Out of a total of 51 samples, 69% of them have nitrate-nitrogen levels of 5 mg/l or
                       greater, and 31% are greater than or equal to the recommended limit of 10 mg/l. The average of all the
                       samples is 9.2 mg/l, with the highest reading at 38.0 mg/l.

                       The nitrate-nitrogen levels here are on average much higher than in the three studies previously
                       described. Again, full analysis cannot be conducted because the USGS report has not yet been published.


                       NITROGEN LOADING ANALYSIS UNDER FUTURE BUILDOUT CONDMONS

                       A nitrogen loading analysis was conducted in the spine recharge area of each of the five wellhead
                       protection areas (WPA's) under permitted pumping conditions. This was done to predict the future
                       nitrogen concentration in the ground water which can be expected if the land area in the spine is
                       built out under the current regulations. A summary of the results of this analysis are presented in
                       Table 8-11. The more detailed computer spreadsheets per area can be found in Appendix F. The
                       nitrogen loading analysis indicates that the nitrogen concentrations in all but one WPA exceed the
                       EPA drinking water standard of 10 mg/l nitrate-nitrogen.

                               Table 8-11: Nitrogen Concentration By Wellhead Protection Area

                               Wellhead                           Predicted Average
                               Protection area                    Nitrogen Concentration (mg/1)


                               A, all soils                                 5.6
                               A, w/o Arapahoe soils                        5.5
                               B, all soils                                 13.5
                               B, w/o Arapahoe soils                        13.5
                               C                                            8.3
                               D                                            7.8
                               E                                            7.1



                       A breakdown of the nitrogen loading by source and WPA are presented in Table 8-12. The major
                       sources of nitrogen vary depending upon the land use in that area.


















                            Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia

                                                                            8-15








                         Table 8-12.- Nitrogen Loading Under Future Buildout Conditions In Spine Of Wellhead
                                              Protection Areas Per Source (Percent of Total)

                   Wellhead Protection load from       load from load from       load from load from       TOTAL
                          Area             sewage       lawns      agriculture landfills      animal  burial

                   A, all soils             20            4               65          0            10        99
                   A, w/o Arapahoe soils     5            0               83          0            10        98
                   B, all soils             20            2               16          58           3         99
                   B, w/o Arapahoe soils    20            2               16          58           3         99
                   C                        67            12              14          0            5         98
                   D                        69            14                9         0            6         98
                   E                        77            17                4         0            0         98

                   Note: pavement, roofs, natural area and septage lagoons were left off this summary table because
                   these sources contributed less than one percent of the total nitrogen load


                   The main sources of nitrogen under future buildout conditions are residential and commercial
                   sewage, agriculture, and chicken burial. The actual percentage that these sources contribute vary
                   by WPA.
                   In those WPA's where composting of dead chickens occurs, it can be a significant source of nitrogen,
                   up to 10% of the total load. Agriculture contributes between 4 and 83 percent of the nitrogen load
                   depending on the wellhead area. The landfill located within in the spine of WPA B is predicted to
                   contribute 58 percent of the nitrogen concentration under future buildout conditions in this wellhead
                   protection area. This analysis demonstrates that a landfill located on the spine recharge area has
                   the potential to have a significant effect on water quality, assuming that the landfill is unlined.
                   In WPA E, in Northampton County residential sewage is the main source of nitrogen, comprising 77
                   percent of the nitrogen load. Sewage is the main source of nitrogen in this area because there are no
                   poultry farms in Northampton County, and under future buildout conditions, the agriculturally
                   zoned area can be completely subdivided into house lots, which was the scenario tested in this
                   buildout. Considering the low residential growth rate and the current high level of agriculture,
                   this may be an unlikely scenario.

                   Nitrogen loading scenarios discounting soils poorly suited to development (Arapahoe) were
                   analyzed for northern Accomack County. Though the overall loading of nitrogen does not change,
                   the major contributor (agriculture) increases from 65% to 83% when residential development is
                   lowered. Thus, if agriculture is a more dominant land use in the future than residential
                   development, nitrogen loading from farn-ting will become the most significant contributor of this
                   contaminant.

                   The future nitrogen loading results indicate that, nitrogen concentrations in the shallow Columbia
                   aquifer are expected to increase to levels approaching the drinking water standard of 10 mg/l. In
                   WPA B the concentration is expected to exceed this value (13.5 mg/D. Since these values are
                   average recharge concentrations, individual measurements of ground water quality will most likely
                   result in much higher concentrations at locations near major sources of nitrogen use or loading. The
                   landfill located in WPA B should be assessed in more detail to determine its potential impact on
                   water quality and -nitrogen loading. In addition, the implementation of agricultural nutrient
                   management plans will help to lower the average nitrogen concentration in the ground water.
                   Other than sewering, little can be done to reduce the load from septic systems. Guiding


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                   development and sanitary wastewater discharges away from the spine recharge will help to
                   reduce the nitrogen load from this source. As the area develops and more residential units are
                   constructed, loading from lawns is expected to increase. Public education on the proper use of lawn
                   fertilizers is the major mechanism to control this potential source of nitrogen.

                   These results indicate that under current conditions, nitrogen values in the ground water on the
                   average are very good due to the large amounts of open and forested land found on the Eastern
                   Shore. In addition, nitrogen concentrations in the vicinity of agricultural operations can be expected
                   to be higher than background levels. More water quality testing and analysis in the Columbia
                   aquifer is needed to obtain a better representation of water quality and how it changes across the
                   Eastern Shore.
















































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                    SECTION 9: CASE STUDIES AND THEIR APPLICABILITY TO THE EASTERN
                                    SHORE OF VIRGINIA


                    This section describes a range of regulatory, non-regulatory, and legislative strategies which have
                    been shown to be successful in protecting ground and surface water supplies in other parts of the
                    United States. The case studies selected illustrate several different water resource protection
                    strategies which may potentially benefit the Eastern Shore's efforts to protect its surface and
                    ground waters.


                    AGRICULTURAL PRACTICES


                    Lancaster County, Pennsylvania:
                    Fertilizer Effects on Water Quality

                    Lancaster County, Pennsylvania is an agricultural area located south and west of Philadelphia.
                    The current technology, econon-dc incentives, and social structure have led to a focus on dairy,
                    livestock, and poultry production. Like the Eastern Shore of Virginia, Lancaster County covers a
                    small percentage of the state (5%), but ranks high in agricultural production. In fact, Lancaster
                    County raises 15.5% of the dairy cows in the state, 38.5% of the swine, 14% of the beef animals, 39%
                    of the broilers, 48.75% of the laying hens, and 5.8% of the sheep. Manure disposal and excessive use
                    of fertilizers pose a pollution problem to surface and ground water sources and to the Chesapeake
                    Bay via outflow of the Susquehanna River.

                    A study was done by the USGS to detern-dne the nutrient contents in two waterways, the Conestoga
                    Headwaters and the West Branch of the Susquehanna River. The Conestoga River watershed has
                    deep, well drained soils that are derived from limestone. The land is fertile and supports corn and
                    alfalfa crops as well as some tobacco, soybeans, and vegetables. The West Branch of the
                    Susquehanna, used as a control, drains lands from northern Pennsylvania where more land remains
                    as forest and less intensive agriculture takes place. The results of the study are shown below.


                                         Table 9-1: Sampling Results in Two Pennsylvania Rivers

                                  Parameter                      Conestoga            W. Branch
                                  (kg/ha)                           1986                 1985
                                  Total P                           1.8                  0.13
                                  Total N                           38.9                 5.2
                                  Suspgnded Sediment                877                  100

                    In a separate study, soil samples were taken at various depths from highly manured fields in 1982,
                    1984, and 1985. Access to the fields was obtained by adult education leaders working with farmers
                    who were concerned about effects of their farn-dng practices on ground water quality and ultimately
                    the Chesapeake Bay. The results showed that many fields contained enough nitrate-nitrogen at
                    the end of the growing season to produce another crop of field corn. While some of the nutrient will
                    remain in the rooting zone for the next growing season, an unknown amount of nitrate-nitrogen will
                    move with water and percolate through the soil profile.

                    Ground water wells in Lancaster County were sampled in 1982 and 1983 for nitrogen amounts. It was
                    determined that in agricultural areas, 41 to 67% of the well samples had nitrate-nitrogen



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                   concentrations exceeding 10 mg/l. Comparatively, in non-agricultural areas in the county only 9 to
                   27% of the wells measured above 10 mg/l.

                   Given the elevated nitrogen levels in both the wells and the Conestoga River, and the over-
                   fertilization of the crop lands, it was concluded that the fertilization practices played a role in the
                   degradation of the water supplies.
                   As a result of this study, measures have been taken to reduce the amounts of nutrients moving to
                   water sources. Beginning in 1988, crop-available nitrogen was calculated using previous nitrogen
                   mineralization rates plus 25% of that amount. Therefore 45% of the manure nitrogen would be
                   calculated as available nitrogen, reducing the need for inorganic fertilizer to 10 kg N/ha. These
                   changes have been incorporated into a computerized expert system which aims to increase the
                   nitrogen mineralization rates and includes all other management factors that are listed in the
                   Manure Management Manual. The next step in the study is to implement a soil and crop monitoring
                   program to see if residual nitrate-nitrogen levels drop.
                   Other water quality protection techniques include crop rotation, which can help control soil erosion
                   and reduce the nutrient loading to the soils. A series of legume crops will build the nitrogen levels
                   in the soil, and a succeeding corn crop then requires fewer nutrient additives. Manures can supply
                   the nutrients for a second year of corn and small grains. The crop rotation schedule W, A, A, A, A, C,
                   C, where W=wheat, small grains, soybeans; A= alfalfa; C=corn, is a desirable and beneficial
                   schedule in Pennsylvania where part-time farm operators can use manure to fertilize their corn
                   crops which will in turn provide food for the livestock.

                   Source:

                   Baker, Dale E. and Donald M. Crider, "The Environmental Consequences of Agriculture in
                   Pennsylvania". In Majumdar, S.K., Miller, E.W., and Parizek, R.R., eds. Water Resources in
                   Pennsylvania. Easton, PA: The Pennsylvania Academy of Science, 1990. Pages 334-353.

                   General Applicability to the Eastern Shore of Virginia

                   Lancaster County differs from the Eastern Shore in many respects. The topography is more hilly,
                   livestock is an intense industry, and even the cultural practices of Arrdsh and Mennonite peoples
                   raise issues that would not be applicable to Accomack and Northampton Counties. This case study
                   identifies the negative aspects of agriculture, and in particular the over-application of animal
                   waste products. The situations presented in this case study are not found on the Eastern Shore,
                   where most of the farmers are very concerned about water quality impacts from agricultural
                   activities. However, the example serves to document the relationship between agriculture and
                   water quality. Although conditions may vary nationwide, the issue of fertilization and its
                   influence on ground water quality is becoming better understood. In fact, a report in California
                   stated, "nitrate has accumulated in ground water to the degree that farmers reportedly no longer
                   need apply fertilizer to satisfy crop needs" (Ground Water Pollution News, 1989).

                   This case study has general applicability to the Eastern Shore in controlling nitrogen loading from
                   agriculture by incorporating frequent soil testing to determine the residual nitrogen that is
                   available in the soil for uptake by a new crop. Cooperative extension agents could institute soil
                   testing programs to track residual nitrogen levels in soils and help farmers better calculate
                   fertilizer additions necessary to meet crop production requirements. Until 1990 soil testing was a
                   service provided by the state at no cost to farmers and homeowners of Virginia for assuring water
                   quality. In past years, approximately 98% of Eastern Shore farmers utilized this service. The
                   service is no longer free and a fee is charged. Preliminary data indicates that the number of


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                    samples submitted for analysis under the fee system has declined by 67%. Nutrient management is
                    a practice that is well established on the Eastern Shore and should continue to be a major focus for
                    the protection of water quality.

                    Jefferson County, Wisconsin:
                    Controlling Disposal of Livestock Wastes

                    Jefferson County is an agricultural county located in southeastern Wisconsin. Homes, farms, and
                    businesses generally depend on ground water for their water supplim The county was concerned
                    that there was no regulatory procedure for determining the impacts to water quality from the
                    intensive agricultural activities occurring within wellhead protection areas (WHPA's).

                    The primary issue centered on the use and disposal of animal wastes. Rainwater percolates
                    through tons of manure generated by feedlot operations annually (stored unconverted) and then
                    infiltrates into the ground, carrying high concentrations of nutrients. Manure applied as fertilizer
                    contributed to elevated nitrogen levels in ground and surface waters.

                    The county developed a zoning ordinance which required a conditional use permit for feedlots
                    larger than a threshold size of 35 acres and possessing a minimum of 150 livestock units 0 livestock
                    unit is equivalent to 1000 pounds live anirrul weight). Adopted in 1975, the ordinance's permit
                    application required that the proponent provide background water quality data, particularly for
                    bacteria and nutrient concentrations; rates and timing of manure applications; and existing nutrient
                    levels in the soils. The county did not aggressively implement the ordinance until 1980 following
                    complaints from some of the county's 60,000 residents about the odor resulting from the feedlots,
                    especially poultry feedlots. The county then moved to prohibit feedlot operations on lots smaller
                    than 35 acres in size, which were seen to be a significant source of pollutant loading. The county is
                    currently preparing an ordinance which will regulate the design and siting of a manure containment
                    facility for lots above threshold limits.

                    According to county officials, implementation has been difficult given the limited staff size of four
                    for the entire county. The ordinance does not control the use of inorganic fertilizers, which are
                    becon-dng more popular as a reaction to the stricter controls on animal manure applications.

                    General Applicability to the Eastern Shore of irginia

                    Agricultural practices have been often cited as major non-point sources of ground and surface water
                    pollution. Given the large areas of existing and zoned agricultural land uses on the Eastern Shore,
                    this case study provides an appropriate example of agricultural land use controls. In particular,
                    Accomack County may require development of similar ground water protection mechanisms which
                    would control the uses of animal wastes and inorganic fertilizers within particularly vulnerable
                    water resource protection areas from poultry wastes and set up a reporting and monitoring system.
                    Specific implementation recommendations from Jefferson County can be readily applied throughout
                    the Eastern Shore to control nitrogen leaching from poultry waste.

                    For More Information

                    Mr. Bruce Houkum, Zoning Administrator, Jefferson County, Wisconsin,
                    (414) 674-2500.

                    Mr. Gordon Stevenson, Project Officer, Animal Wastes Management Office, Department of Natural
                    Resources, Madison, Wisconsin, (608) 267-9306.




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                   Delmarva Peninsula:
                   Composting Chickens

                   The poultry industry is currently enjoying a good economy. However, the problem of disposing of
                   dead birds that never reach the factory is affecting the industry as a whole. Traditional methods
                   of disposal, which include burial (risk of ground water contan-tination), incineration, deposition in
                   the woods, and feeding dead chickens to hogs and other chickens (rendering) are health hazards
                   and may also be illegal. However, a natural mortality rate that ranges from 0.1% to 8% can be
                   expected in a flock which takes 45 days to raise. The Delmarva Peninsula, in particular, has a
                   fragile ecology and chicken growers must be concerned with causing further contamination to the
                   Chesapeake Bay.
                   Dr. Dennis Murphy, a member of the faculty at the Department of Poultry Science at University of
                   Maryland at College Park, has developed a method for disposing of dead poultry by composting.
                   The idea of composting is itself not a new idea, but Dr. Murphy has applied it to the poultry
                   industry such that it can handle the volumes of chickens in an inexpensive and environmentally
                   sound way, and is not a health hazard.
                   The process of composting involves nitrogenous materials (in this case, manure and dead birds) and
                   carboniferous material (cellulose paper, sawdust, or straw stover). These ingredients are converted
                   to hun-dc acids, bacterial biomass, and organic residue with the action of aerobic, thermophilic,
                   spore-forn-dng bacilli. Heat, carbon dioxide, and water vapor are all generated as byproducts.

                   In order to compost, the chicken grower must construct a composting structure. The facility can vary
                   in many ways but it must have a roof, an impervious weight-bearing foundation such as concrete,
                   and rot-resistant building materials. These requirements allow for year-round use, prevent
                   contan-tination to surrounding areas, and help control the amount of moisture that goes into the
                   system.

                   To begin the composting process, a bin is filled with several sequential layers of straw, chickens,
                   and manure, the proportions of which have been detern-dned by Murphy. Within two to four days
                   of loading, the temperature within the bin should increase rapidly and reach a peak of 135-150'F.
                   The chickens are effectively cooked, and pathogens are killed in conditions above 130*F. After ten
                   days, the temperature drops. The contents of the bin are then removed with a front-end loader and
                   stored in a second bin. The action of transferring the contents to a new location aerates the n-dxture,
                   and in the secondary bin, the temperature rises again. Only two stages are needed, and within a
                   matter of weeks, the chicken carcasses become compost material of similar texture to that of organic
                   soil. The process is virtually odorless, according to Murphy.
















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                                            Figure 9-1 Scheme of Simple Poultry Composter



                                                     - 8 fL Wkw -







                                                                    C> C>     4-           MWWM
                                                                                           P-Abry
                                           U3
                                                                                           sftw


                                                                  C> C>   Cn.              menu=
                                               . ......................... C>



                             Source: University of Maryland Cooperative Extension Service, Fact Sheet 537

                  The temperature of the chicken/manure/straw composition must be monitored during composting in
                  order to assure that everything is going properly. Murphy estimates that the normal daily
                  operation of a composter designed to handle 1,050 lbs. of carcasses per day requires twenty minutes.
                  This estimate includes all activities, such as loading, monitoring temperatures, adding water, and
                  moving compost. The cost of running a composter is 03 Ob. spread over a ten year depreciation
                  schedule. By comparison, incineration costs 3-80b. over a five year schedule.
                  One grower in Maryland has begun selling the composted chickens as a soil conditioner and
                  enricher. The resulting compost is an excellent mild fertilizer. A five-county poultry region in
                  southwest Missouri is launching a demonstration project that will dispose of dead birds by a
                  composting process. In 1987, the region had a poultry population of 33 million broilers, 10 million
                  turkeys, and 4 million layers. The objective is to compost two million dead birds from the area
                  annually. The Missouri State Committee of the Agricultural Stabilization and Conservation
                  Service has approved the composter for Agricultural Conservation Payment (ACP) cost-sharing.
                  Hopefully more states will create incentives for composting via the cost-share program.
                  In short, composting chickens is a simple and economic method of disposing dead birds. It does not
                  contribute to ground water contamination, and creates a salable product.

                  General A1212licabilily to the Eastern Shore of Virginia
                  Several growers on the Delmarva Peninsula already employ the composting method to reuse and
                  recycle waste products from the chicken raising industry. Chicken growers should seek assistance
                  from County Extension Agents and the Cooperative Extension Service on methods, materials, and
                  cost to compost chickens. Composting can create a valuable product that can be used as a mild
                  fertilizer and soil conditioner.


                  For More Information

                  Dr. Dennis W. Murphy, Cooperative Extension Service, Route 2, Box 229-A, Princess-Anne,
                  Maryland, 21853, (301) 651-9111.



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                  ON-SITE WASTE DISPOSAL


                  Ontario, Canada:
                  Nitrogen Plumes from Septic Systems
                  One-third of the population of North America uses septic systems for disposing of liquid wastes.
                  This practice accounts for the largest volumetric source of effluent discharged into the ground water
                  zone. Septic systems located on sand and gravel aquifers are a potential source for producing large-
                  scale contaminant plumes in aquifers that are also likely to be used for the drinking water supply.
                  Robertson, Cherry, and Sudicky (1990) used ground water monitoring networks to investigate ground
                  water impacts caused by septic systems at two single-family homes in Ontario. The homes were
                  located on shallow, unconfined aquifers. Several water-table piezometers were installed, and
                  sediment cores were sampled continuously. The older site, at Cambridge, had a septic system in
                  operation since 1977. The field investigation started in 1987. The younger site was located at
                  Muskoka, and was monitored six months after the beginning of full-time use in 1987. Both septic
                  systems were of the conventional design used in Canada and the U.S. for permeable soils.
                  The tests yielded several results. The plume shape at the Cambridge site demonstrated that the
                  flow within the aquifer was predominantly horizontal except beneath the tile bed where the
                  plume followed a vertical path such that it nearly reached the bottom of the aquifer. Using a
                  bron-dde tracer, average tank residence time was found to be two days. In Cambridge, effluent
                  residence time in the 2-m-thick unsaturated zone was 10 days, whereas at Muskoka, the bromide
                  tracer experienced a longer residence time in the 3-m-thick unsaturated zone at this site, in the
                  order of several weeks to months. Flow velocities were calculated at both sites.

                  Nitrogen in septic systems is about eighty percent (80%) inorganic, predominantly ammonium
                  [NH4+-N]. At both sites, tile effluent concentrations for NH4+-N ranged from 30-59 mg/I and
                  nitrate-nitrogen [N03--N] concentrations from 0.1-1.0 mg/l. Comparatively, plume core chen-dstry
                  revealed almost the opposite concentrations, with NH4+-N concentrations at 0.1-0.5 mg/1 and
                  N03--N at 33-39 mg/l. This suggested that the ammonium in the effluent was being oxidized via
                  n-dcrobial nitrification, as in the following equation:
                                                  NH4  + + 202 --> N03- + 2H+ + H2

                  Low dissolved oxygen content levels and high nitrate-nitrogen levels observed even in the
                  shallowest water table zone below the tile fields indicated that the processes in the above
                  equation are largely completed during residency in the unsaturated zone, but also continue below the
                  water table.

                  A three-dimensional analytical model was used to obtain estimates of the aquifer dispersion
                  parameters within the saturated zone. Modeling results indicated that transverse dispersion rates
                  at both sites were low. The detailed findings were significant in that they were consistent with
                  very detailed tracer tests recently performed at Twin Lakes, Ontario and Cape Cod, Massachusetts.
                  At the Cambridge site, which had been in operation for twelve years, the plume had sharp lateral
                  and vertical boundaries, and was more than 130 meters (427 ft) in length and had a uniform width
                  of about 10 meters. After 1.5 years of use, the Muskoka plume began discharging to a river located
                  20 meters (66 ft) from the tile field. At the organic-rich riverbed, denitrification, or nitrate
                  attenuation, occurred such that little nitrate-nitrogen was actually discharged into the stream.



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                   The model was employed to make nitrate-nitrogen predictions at the Cambridge site. Using the
                   transn-tissivity rates at Cambridge, a source concentration of 33 mg/I N03--N, and a background
                   level of zero nitrate, the steady state plume length which would exceed the drinking water
                   standard of 10 mg/l N03--N is 170 m (558 ft).

                   The authors use their study to issue the following warning, "Therefore, for many unconfined sand
                   aquifers, the minimum distance-to-well regulations for permitting septic systems in most parts of
                   North America should not be expected to be adequately protective of well-water quality in
                   situations where mobile contaminants such as N03- are not attenuated by chemical or
                   microbiological processes."

                   Source:

                   Robertson, W.D., Cherry, J.A., and Sudicky, E.A., "Ground-Water Contamination from Two Small
                   Septic Systems on Sand Aquifers", Ground Water, January-February, 1991, p. 82-92.

                   General Applicability to the Eastern Shore of Virginia

                   This recent study presents important information for Eastern Shore residents. In areas where septic
                   systems are dense and people rely upon private wells screened in the shallow aquifer, nitrogen
                   levels can be expected to be 10 mg/I at close to 600 feet from the septic system. On the Eastern
                   Shore, proper well spacing from septic systems may require a setback of up to 600 feet due to the
                   very sandy soils, and shallow depth to the water table.


                   Falmouth, Massachusetts:
                   Performance Standards Within Zones of Contribution

                   Falmouth is a coastal town on Cape Cod, Massachusetts. The town typically experiences a large
                   increase in population during the summer months with the influx of seasonal residents. The town's
                   water supply, however, is limited to its aquifers which are part of the Cape Cod sole source
                   aquifer. With the residential development boom of the early to mid 1980's, large amounts of
                   previously undeveloped areas were subdivided and developed for residential and commercial use.
                   The higher residential density and greater numbers of on-site sewage disposal systems began to
                   affect ground water quality, particularly by raising nutrient concentrations in ground waters.

                   The situation was severely aggravated after a 500,000 gpd public water supply was forced to close
                   because discharges from an upgradient sewage treatment plant had contaminated the aquifer.
                   Serious concerns were raised about the main water supply, which was located downgradient of the
                   town landfill, a sewage treatment plant, an industrial park, and extensive residential
                   development. Worse still, the town's zoning allowed for a saturation build-out population three
                   times that of the present. In short, existing and programmed land uses seriously threatened the
                   town's ground water supplies.
                   In response to these concerns about existing and potential water supply contamination, the town
                   delineated the zones of contribution and associated recharge areas for all drinking water supplies
                   and surface water bodies. After identifying priority protection areas, the town developed and
                   adopted a set of performance standards together with a methodology for determining cumulative
                   loading impacts to ground water quality. The standards essentially limited further development
                   within a zone of contribution or surface watershed if the added nutrient loading from the land use
                   would increase the ground or surface water concentrations of those nutrients past certain thresholds.


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                   In order to accommodate already planned developments within the Ground and Surface Water
                   Resource Districts, the town adopted a transfer of development rights program, which was
                   expected to encourage development outside of the delineated zones of contribution and surface
                   watersheds.

                   General A1212licability to the Eastern Shore of Virginia
                   Nutrient management by performance standards has been shown to be an effective and defensible
                   method of managing development within vulnerable ground water recharge areas. Our nutrient
                   loading analysis indicates that nitrogen loading performance standards should be adopted and
                   enforced at some point in the future on the Eastern Shore. Saturation build-out would generate
                   significant increases in ground water nitrogen concentrations given the potential programmed
                   increase in associated loadings from septic systems, lawn and farm fertilizers, roadway and
                   parking lot runoff, etc. By devising nitrogen loading performance standards for development
                   located within the recharge areas, the Counties may successfully prevent contarnination of their
                   drinking water supplies from nitrogen. Specific control over nitrogen is more appropriate for the
                   shallow water table aquifer than for the deeper aquifers used for drinking and industrial water use.

                   For More Information

                   Victoria Lowell, Barnstable County Comn-dssioner, (508) 362-3828.


                   Long Island, New York:
                   Restrictions Within Recharge Zones

                   The Long Island Regional Planning Board has been working on ground water protection issues for the
                   two counties of Nassau and Suffolk for several decades. Originally, primary issues of concern
                   revolved around ground water quantity and the potential for salt water intrusion. More recently
                   there has been a focus on ground water quality concerns.

                   Studies such as the regional 208 wastewater study, published in 1978, pointed to the need for
                   increased water quality protection strategies for two types of recharge zones, deep recharge and
                   shallow recharge zones. The zones are delineated according to the distance between surface level
                   and ground water elevation over which infiltrating rainwater travels vertically. The shallow
                   recharge zones are typically found closer to the ocean shoreline. The deep recharge zones were seen
                   as more critical resources because they contained much larger quantities of ground water; many were
                   found to still contain excellent water quality.

                   The Regional Planning Board worked with the state health agencies, water suppliers,
                   municipalities, and counties in developing a number of land use controls to prevent water quality
                   impacts from on-site septic systems. These waste disposal systems were considered an important
                   source of contaminants.

                   Conventional septic systems provide minimal treatment of wastewater. Leaching facility effluents
                   contain approximately 40 to 60 mg/I of nitrogen. The effluents also contain high phosphorus
                   concentrations and large numbers of pathogenic bacteria and viruses. Septic systems can also
                   introduce hazardous wastes into the ground water if the owner uses septic cleaners or pours
                   household hazardous wastes down the drain. The cumulative effects of many small septic systems
                   on nutrient, pathogen, or hazardous waste levels in downgradient waters can be very significant.
                   These impacts are dependent upon septic system location and density relative to receiving water
                   bodies.



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                    Accordingly, several land use programs were implemented. The Regional Planning Council assisted
                    in the development of recommended minimum lot sizes for undeveloped deep recharge areas. They
                    recommended a n-dnimum area of two acres as a means of ensuring adequate dilution of septic system
                    effluents within the protection district. The planning board and the counties also worked together
                    to organize bans on the sale and use of septic system cleaners, which have been shown to be
                    significant sources of hazardous material contan-tination. Presently, the local and regional
                    authorities are developing septage districts and accompanying regulations which would oversee
                    the regular pumping out of household septic systems. This can greatly improve treatment
                    performance and reduce the opportunity for breakouts.

                    General AR12licability to the Eastern Shore of Virginia

                    The regular pumping of septic systems is a management technique currently being required by the
                    Chesapeake Bay Preservation Act for the Eastern Shore. The Long Island example can be used to
                    develop a septic system management program for this area. Potential and even existing residential
                    development and the accompanying septic systems are a source of ground water contamination
                    within the shallow recharge areas. By adopting similar land use controls and regulations on the
                    siting and operation and maintenance of such systems, Accomack and Northampton Counties may be
                    able to eliminate the possibility of nutrient and hazardous waste contan-driation in vulnerable
                    ground water recharge areas.

                    For More Information

                    Ms. Edith Tannenbaum, Planning Director, Long Island Regional Planning Board, Long Island, New
                    York, (516) 360-5189.



                    Gloucester, Massachusetts:
                    Siting of Septic Systems

                    The City of Gloucester, Massachusetts recently developed ordinances governing the siting of septic
                    systems in order to protect sensitive ground water supplies.
                    Septic system effluent contains a large number of pathogenic bacteria and viruses. Under certain
                    geologic conditions, the effluent may travel rapidly, reducing the potential for treatment by soil
                    filtration and increasing the risk to human health. Much of Gloucester consists of shallow sandy
                    sediments overlying bedrock. When a septic system leaching field is constructed in an area with
                    shallow depths to bedrock, the effluent will quickly percolate through the sediments without
                    receiving adequate treatment. The effluent then moves along the the bedrock surface, allowing it to
                    quickly reach a water supply well.

                    The City's officials, concerned over the potential threat to drinking water supplies, adopted two
                    health ordinances governing the siting of septic systems. Any proposed sewage disposal system
                    which lies within 600 feet of a drinking water well or a surface water body would not receive a
                    Disposal Construction Works Permit until the proponent had submitted sufficient hydrogeologic
                    information to demonstrate that there was a minimum travel time of 50 days between the leaching
                    facility and the downgradient water resource. Similarly, the Board of Health would not approve
                    the subdivision plans until the performance standard of 50 days n-dnimum travel time had been
                    shown by the project proponent.





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                  General Applicability to the Eastern Shore of Virginia

                  The soils on the Eastern Shore are very sandy and allow for the rapid movement of water. The
                  shallow depth to water may also assist in the transport of viruses. The Counties should consider
                  some form of private well/septic system ordinance to provide the maximum protective distances
                  between these features.


                  For More Information

                  Board of Health, City of Gloucester, 41 Washington Street, Forbes Building Annex, Gloucester,
                  Massachusetts, (508) 281-9771.


                  Locations Throughout the U.S.:
                  Constructed Wetlands, Alternative to Conventional Wastewater Treatment

                  Constructed wetlands are defined as those systems specifically designed for wastewater treatment.
                  They are not subject to laws and regulations involving natural wetlands, and are generally located
                  in areas where natural wetlands did not previously exist. Constructed wetlands provide secondary
                  wastewater treatment, advanced waste treatment, or sludge management for smaller towns, rural
                  communities, and industrial plants. Aquatic plants and tiny n-dcrobes are used to replace costly
                  mechanical pumps and industrial chemicals required by conventional wastewater treatment plants.
                  Part of their popularity is due to their low cost and the simplicity of operation.

                  The purification process is a simple one. In an initial holding tank, sludge undergoes primary
                  treatment where the sediment settles out. Then waste water flows into pathways lined with rock
                  and filled with emergent wetland plants. The rock is a home for bacterial slime that digests the
                  organic wastes. Microbes on the aquatic plant roots perform a similar function. Meanwhile the
                  plants draw nourishment from the effluent and absorbs the resulting proteins, starches, and sugars.
                  The plants inject oxygen into the water to nourish the bacteria, and also contribute oxygen to the
                  air, helping to regulate the level of carbon dioxide in the environment. The wetlands typically
                  include some type of barrier to prevent ground water contamination beneath the bed. The barriers
                  used thus far range from compacted earth to membrane liners. Other systems are completely
                  enclosed in a series of containers.

                  Currently, constructed wetlands are being used throughout the country, with the greatest
                  concentration in Tennessee, South Dakota, Louisiana, and Mississippi. The design capacities of the
                  systems range from 10,000 gallons per day in El Dorado, New Mexico, to 20 million gallons per day
                  in Orlando, Florida. In Anne Arundel County, Maryland, a water reclamation facility has been
                  operational since December 1988 and handles a flow of approximately 500,000 gallons per day. The
                  Mayo, Maryland facility is a septic tank effluent collection and treatment system, and utilizes the
                  following components: recirculating sand filters, bulrushes (the emergent wetlands), peat wetlands,
                  ultraviolet disinfection, and discharge through an offshore wetland into Chesapeake Bay. The
                  system comes consistently under NPDES Permit effluent requirements for the facility.

                  In 1988, the mountain community of Monterey, Virginia began using a constructed wetlands system
                  built at a capital cost of only $150,000, and with operating costs a fraction of running a mechanical
                  facility. The decision to shift its water treatment facility to a constructed wetlands was mainly an
                  economical one. The 190 customers had an average household income of $14,000, and the community
                  did not have the resources to cover the costs to meet new state requirements ($500,000). For this
                  system to operate successfully, special plants had to be considered to withstand periods of sub-



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                     freezing temperatures in the winter. Between June 1989 and June 1990, the system treated 20,000
                     gallons per day, and fell within discharge standards.

                     In addition to municipal systems, the constructed wetlands have also been used at individual homes
                     and as treatment facilities for subdivision areas. There are potential applications in agribusiness
                     and for filtering heavy metals and toxic chemicals out of industrial effluent.

                     For more information:

                     NCW Systems, Inc., 5711 Staples Mill Road, Richmond, Virginia, 23228, (804) 264-7810.

                     General Applicability to the Eastern Shore of Virginia

                     Constructed wetlands offer a final wastewater treatment alternative that is very applicable to the
                     Eastern Shore. Since a majority of the coastal marshes on the ocean discharge side of the Eastern
                     Shore are in public conservation ownership, incorporating artificial wetland systems can be very
                     appropriate for most discharge facilities. The use of these systems will allow residential and
                     industrial development to proceed in areas where conventional surface water discharges would
                     cause water quality effluent problems. In particular, the County of Northampton would benefit
                     from artificial wetland systems because of the large amount of marshland that is found in the
                     County and the high degree of final wastewater treatment that can be achieved from these
                     systems. The low cost and simplicity of operation would also be of great value on the Eastern Shore.


                     SURFACE WATER MANAGEMENT

                     Chesapeake Bay Area, Maryland:
                     Stormwater Pollutant Reduction

                     Stormwater management is one component of the US EPA's National Estuarine Program for the
                     Chesapeake Bay Area of Critical Concern. The tremendous increase in development activities
                     within the Bay area has had serious impacts on the Bay's water quality. Point and non-point
                     sources of pollution were targeted for action, beginning with limiting various land uses in the near
                     shore areas.

                     Stormwater was identified as one of the major non-point pollution sources to the Bay, along with
                     agricultural practices. Runoff from roadways, parking lots, overloaded or poorly designed
                     stormwater sewers, and poor soil conservation practices usually carries a very significant amount of
                     pollutants, including metals, volatile organic compounds, oils and grease, nutrients, bacteria and
                     viruses and suspended solids.
                     Nutrients and suspended solids have been shown to cause adverse impacts to the Bay's water and
                     habitat quality for a wide range of upper Bay organisms. Nitrogen, and to a lesser extent,
                     phosphorus, acts to encourage the rapid growth of algae and aquatic plants, which can reduce the
                     dissolved oxygen content of the waters. In turn, the lower oxygen content stresses or kills fish.
                     Suspended solids from soil-laden runoff block light and harm plankton and other photosynthetic
                     organisms.
                     With the passage of the Bay Critical Area Law in 1985, the State of Maryland took an aggressive
                     step forward in reducing point and non-point source pollution to the Chesapeake by restricting land
                     uses within the watershed. Local communities were required by law to assign their lands falling
                     within the Critical Area to one of three broad land use areas: Intensely Developed, Limited


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                    Development, and Resource Conservation Areas. The table below describes how the Commission
                    defined each land use category and the pollutant reduction goals set for each.


                               Table 9-2: Pollutant Reduction Goals by Land Use Categories, State of Maryland

                                                INTENSELY                 LIMITED                    RESOURCE
                                                DEVELOPED                 DEVELOPMENT                CONSERVATION

                    Characteristics             Dense residential         Mixed land usage:          Primarily open fields,
                                                institutional, com-       not dominated by           wetlands, forest, and
                                                mercial, or indus-        wetlands, agriculture,     agriculture.
                                                trial uses.               forest or open space.

                                                4 or more dwelling        1 dwelling unit per 5      Less than 1 dwelling
                                                units per acre.           acres up to 4 per acre.    unit per acre.

                                                Public water & sewer      Areas with public          No public water or
                                                serving at least 3        water, sewer or both.      sewer service.
                                                dwelling units per
                                                acre.


                    Criteria                    Reduce pollutant          Restrict removal of        Residential develop-
                                                loadings by minimum       existing forest land to    ment limited to overall
                                                10% from predevelop-      20% when develop-          density less than 1
                                                ment loadings.            ment occurs.               dwelling unit per acre.

                                                Reduce nonpoint           Restrict impervious        Encourage agriculture &
                                                impacts to streams &      area to 15% of land        forestry.
                                                tidal waters from         area being developed.
                                                redevelopment.

                                                Protect remaining         Encourage clustering
                                                wildlife & fish           of dwelling units to
                                                habitats.                 conserve natural
                                                                          habitats.




                    Within intensely developed areas, such as the City of Baltimore, the Critical Area Commission
                    has developed and implemented what it calls the 10% rule: any new development or
                    redevelopment of a site must employ stormwater pollution control methods to ensure that the
                    resulting pollutant loading from the new activity is at least 10% less than that from the existing
                    land use. This rule was developed as a means of meeting the pollutant reduction criterion listed in
                    the table above.

                    The 10% rule procedure consists of nine steps which determine whether the proposed new
                    development or redevelopment must comply. The procedure also estimates existing and post-
                    development runoff rates and pollutant loadings, and compares pre- and post-development
                    stormwater pollutant loadings to see if the latter loading is at least 10% less than the former. In
                    essence, local jurisdictions with areas classified as Intensely Developed must evaluate each




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                   regulated proposed development using the 10% rule to ensure that the area's overall pollution
                   loadings from stormwater runoff are decreasing.

                   General Applicability to the East rn Shore of Virginia

                   Northampton County's Master Plan attempts to address the new issues associated with Virginia's
                   Chesapeake Bay Preservation Act. Land development densities have decreased in the County as a
                   result of the County's new ordinance. Some version of the 10% rule for new development adopted by
                   the Chesapeake Bay Program in Maryland may be an effective mechanism for gradually but
                   consistently achieving stormwater-related pollution reduction within intensely developed areas on
                   the Eastern Shore.


                   For More Information:

                   Framework for Evaluating Compliance with the 10% Rule. Chesapeake Bay Critical Area
                   Commission, Annapolis, Maryland, (301) 974-2426.

                   Maryland Department of the Environment, Stormwater and Sediment Division, Mr. Vince Berg,
                   Director, (301) 631-3553.


                   Buzzards Bay, Massachusetts:
                   Stormwater Treatment System

                   Established in 1985, the US EPA/Commonwealth of Massachusetts-supported Buzzard's Bay
                   Project was made part of the National Estuarine Project in order to protect the Bay's sensitive
                   environmental resources. A draft Comprehensive Conservation and Management Plan (CCMP) for
                   the project area, released in May, 1990, outlines the Buzzards' Bay environment, priority pollution
                   problems and summarizes the project's action plans for addressing these problems.

                   According to the CCMP, stormwater runoff comprises one of the major pollution sources to the
                   estuary and bay. As described above for the Chesapeake Bay Critical Area, the runoff contains a
                   wide variety of pollutants which can adversely affect the bay's water and habitat quality. Runoff
                   from stormwater drains was identified as a priority problem because it is known to carry large
                   quantities of fecal coliforms, viruses, metals, pesticides, and VOC's.
                   The project identified two large stormwater drains which served two suburban areas and directly
                   discharged runoff into the bay as sites for pilot demonstration projects in stormwater-runoff control
                   technology. The two sites were Electric Avenue in Boume and Red Brook in Wareham.

                   A stormwater treatment structure resembling a large septic system was constructed under the
                   parking lot for the Electric Avenue beach. The structure serves to divert and hold runoff flows,
                   allowing sediments and associated pollutants to settle out while the water infiltrates into the
                   subsurface soils. The settling tanks will be emptied regularly. A ground water monitoring system
                   was also put in place to gauge ground water quality impacts. Prelin-dnary results have shown that
                   the system is extremely efficient in removing indicator pollutants, such as fecal coliforms, (a
                   common indicator), by 98%.

                   The Red Brook pilot project, now underway, will utilize infiltration ponds to hold stormwater
                   runoff until it infiltrates into the soil.





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                    In response to the success of the Electric Avenue demonstration project, the Buzzards Bay Project is
                    collaborating with the US Soil Conservation Service (SCS) to provide design expertise and funding
                    for construction of similar sediment/ stormwater control devices to several project area communities.

                    The project has also identified the importance of collaboration between various state agencies
                    regarding construction and maintenance of roads. The Massachusetts Department of Public Works is
                    primarily responsible for the design and construction of safe public roads. Concerns over the water
                    quality impacts resulting from the newly constructed roads are usually only secondary in nature.
                    DPW road projects are exempted from review by local conservation commissions. Accordingly, the
                    CCMP has recommended that towns and the DPW work together to minimize stormwater runoff
                    beginning at the preliminary design stage. Potential advantages include reducing the pollutant
                    load through environmentally conscious road design and lowering mitigation construction costs by
                    incorporating mitigation structures within the costs for road construction.

                    General Applicability to the Eastern Shore of Virginia

                    Stormwater runoff is not a major concern on the Eastern Shore of Virginia. However, if there
                    develops a need for more effective management of sediment and stormwater associated pollution,
                    the above case study may provide ideas for better management of stormwater.

                    For More Information

                    Buzzards Bay Comprehensive Conservation Management Plan, May 1990. Buzzards Bay Project, US
                    EPA & Commonwealth of Massachusetts.

                    Dave Janik, Buzzards Bay Project, 2 Spring St. Marion, Massachusetts, 02738, (508)748-3600.


                    Chesapeake Day Area, Maryland:
                    Vegetated Buffer Zones

                    Maryland's 1985 Chesapeake Bay Critical Area Law required local communities to control land
                    uses and reduce pollutant loadings on lands located within the Critical Area. It also specified the
                    establishment of different types of buffer zones for various land uses within the Critical Area.

                    Vegetated buffer strips offer tremendous value in protecting wetlands and surface waters from a
                    variety of impacts for little cost. Buffer strips serve to contain and encourage infiltration of surface
                    run-off, thereby attenuating levels of nutrients, metals, petroleum hydrocarbons, pesticides, and
                    other pollutants. They are less expensive, outside of land costs, than technology-based stormwater
                    control structures in both capital and operation and maintenance costs.

                    Buffer zone and land use regulations for the Chesapeake Bay Critical Area include:

                            1 .      Mandatory soil conservation and stormwater management plans and
                                     adoption of best management practices (BMP's) for all agricultural
                                     lands within five years.

                            2.       25-foot buffer zone along tidal waters and stream courses established
                                     until a soil conservation plan is implemented.

                            3.       Livestock cannot be watered or fed within 50 feet of water's edge.



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                            4.       Prohibit new development and new marinas within 100 feet of
                                     shoreline in Resource Conservation Areas.


                            5.       Delineate a 25-foot minimum buffer zone around non-tidal
                                     wetlands.

                            6.       Establish a 100-foot minimum naturally vegetated buffer zone
                                     around all of the Bay's non-developed areas.

                    These requirements work not only to preserve vulnerable resource areas, but are also effective in
                    fin-dting soil erosion. The buffer zones reduce or eliminate altogether the opportunity for direct
                    discharges of stormwater runoff into sensitive surface waters. In addition, the buffer strips provide
                    critical habitat for a wide range of wildlife species.

                    General AR12licability to the Eastern Shore of Virginia
                    Buffer strips may be important on the Eastern Shore for the protection of coastal tidal wetlands.
                    The buffer strips themselves will act as sinks to utilize nitrogen rich ground water that may be
                    discharging to the shallow system. The specific application of this approach to the Eastern Shore
                    would require more research.

                    For More Information

                    Chesapeake Bay Critical Area Commission, Annapolis, Maryland, (301) 974-2426.


                    HAZARDOUS MATERIALS HANDLING AND STORAGE


                    Portland, Oregon:
                    Land Use Controls Within Wellhead Protection Area

                    The Columbia South Shore Aquifer, located by th6 banks of the Columbia River, was designated as
                    a back-up water supply for the City of Portland. The aquifer lies within the boundaries of the
                    mixed use Columbia South Shore Development Area. Concerns focused on the Wellhead Protection
                    Area (WHPA), which had been delineated rudimentarily using roads as boundaries; the true
                    boundaries were not yet known.
                    The prelin-dnary WHPA and surrounding areas contained a number of different industrial land uses
                    and there was concern that ground water could become contaminated by solvents and petroleum
                    hydrocarbons which were stored, utilized, and produced by different industries.
                    In response to these concerns, city and state agencies established a list of prohibited and/or
                    controlled activities and substances. Certain land uses which involved hazardous materials were
                    prohibited. Use of non-prohibited materials required a water quality impact review before being
                    permitted. Additional regulations stipulated the containment requirements for the storage, use or
                    transport of hazardous materials.
                    Activities and land uses which were prohibited within the WHPA were broad and included uses
                    that heretofore were allowed to exist within Wellhead and Ground Water Resource Districts. For
                    example, gas stations were prohibited, as were all production, storage, or disposal of hazardous
                    materials.




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                   The water quality impact reviews required for uses of non-prohibited hazardous materials were
                   made mandatory upon request from the public or abutters. The use would be permitted only if the
                   proponent could demonstrate that there would be no adverse impacts to ground water quality.

                   After much research, the City developed and published containment requirements for the storage,
                   use, or transport of hazardous materials within the City Handbook. All containment plans had to
                   pass review by the Bureau of Buildings, which would, in turn, consult with the Water Works
                   Department and the Envirorunental Services Bureau.

                   General AWlicability to the Eastern Shore of VirgjnLia

                   The Eastern Shore does not presently possess the same density and range of industrial development
                   found in Portland's South Shore Development Area. However, this case study offers a valuable
                   example of protecting vulnerable ground water resources without banishing already existing
                   industries from the Water Resource Protection Districts. In this way, local and County governments
                   avoid a potential loss in tax revenue and a potential slowdown in econon-dc growth. While the risk
                   of ground water contan-driation from the hazardous materials has not been completely elin-dnated,
                   the Portland approach minin-dzes that risk by only permitting the use of less hazardous materials
                   (with regard to toxicity or quantity) within the Water Resource Protection Districts. The Portland
                   approach could be applied in intensely developed recharge areas found along the spine of the the
                   Shore.



                   Dayton, Ohio;
                   Overlay District For Aquifer Recharge Area

                   The City of Dayton draws upon a glacial outwash aquifer primarily composed of sand and gravel
                   for a large part of its water supply. The aquifer is very permeable and permits rapid ground water
                   travel. However, the aquifer recharge area has already been densely developed by industry.
                   Citizens and local and state government officials were becon-dng increasingly concerned about the
                   threat of ground water contarridnation from the large amounts and varieties of hazardous materials
                   used by the industries.

                   The City delineated a 6,000-acre water resources protection overlay district based on estimated
                   times of travel from potential sources to wells. The overlay district encompasses 550 businesses
                   which use, handle, or store an estimated 200 million pounds of hazardous materials each year.

                   Rather than prohibiting industrial uses or resorting to downzoning (raising minimum lot size
                   requirements and precluding industrial development) within the aquifer protection district, the
                   city's water department devised a hazardous material control program that emphasizes
                   notification and reporting on the types and volumes of hazardous materials used.

                   The Water Department administers the program. Businesses and industries located within the
                   protection district are required to report the types and quantities of chemicals used on site. The
                   department assigns intensity and use ratings based on the material's toxicity, threat to ground
                   water and quantity produced, used or stored. The regulations set limits on the maximum amount of
                   hazardous materials allowed on site. The City funds the program by applying a surcharge to
                   Dayton residents' water bills.

                   Companies which do not use, handle, store or generate quantities exceeding the notification
                   threshold are considered to be "conforming". They are not allowed to subsequently apply for an
                   increase in amount or in number of hazardous materials used on site. An enviror-anental advisory



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                     board was established to hear petitions for the deregulation of materials; the burden of proof is left
                     with the petitioner.

                     The program established a rapid deployment emergency response program which included
                     awarding a clean-up contract to a professional hazardous waste company, which is responsible for
                     providing prompt and effective treatment and extraction of spills. An extensive inspection program
                     was set up to prioritize problem areas and offer corrective solutions.
                     The program's defensibility has been one of its greatest successes. According to the City of Dayton
                     Water Department, since the program's initiation in 1987 no suits have been brought against the
                     City regarding the program. Mr. Hall attributes this to the program's emphasis on regulating and
                     monitoring hazardous material use without directly prohibiting uses or downzoning the district.

                     General Applicability to the Eastern Shore of Virginia
                     The Dayton case study, as with Portland, Oregon, focuses on a heavily industrialized and
                     residentially developed city. The lessons learned from these two case studies are applicable to the
                     Eastern Shore because of the need to address existing industrial and commercial development. The
                     Dayton approach is to monitor and require record keeping for all facilities without closing them
                     down or requiring major infrastructure changes.

                     For More Information

                     Mr. Dusty Hall, Water Department, City of Dayton, Ohio, (513) 443-3600.


                     Palm Beach County, Florida:
                     Ground Water Protection Through Zoning Ordinance
                     Following the closure of 36 water supply wells contaminated with hazardous wastes, Palm Beach
                     County, Florida, developed a zoning-based Wellfield Ordinance to protect its vulnerable ground
                     water supplies. Implemented in 1988, the ordinance received strong support at public hearings and
                     in a referendum, despite the protection area's existing residential and industrial development, and
                     very high density.
                     The ordinance restricts the use, storage, handling, and production of hazardous materials within
                     the protection district. No grandfathering of existing uses was allowed.
                     The protection district was divided into four zones based on hydrogeologic investigations and
                     modeling. The zones were delineated as a function of proximity and extent of recharge contribution
                     to public water supply wells. Uses and presence of hazardous materials are regulated according to
                     the risk or threat posed to wells for each zone. All hazardous materials are prohibited in Zone 1,
                     within which lie the most vulnerable recharge areas. In contrast, businesses and industries can use
                     hazardous materials within a Zone 4 after first securing a pern-dt and establishing a monitoring
                     program-
                     The program is implemented by the county Department of Environmental Resources. Other program
                     components include inspection and monitoring to ensure compliance; engineering and site planning
                     requirements such as spill containment facilities and removal of underground storage tanks (USTs);
                     exemptions for emergency uses or public safety; a phased compliance schedule; and funding for
                     relocating priority industries outside of Zone 1.



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                  General A1212licability to the Eastern Shore of Virginia

                  The Palm Beach case study offers a valuable example to the Eastern Shore in effectively reducing
                  risk of contan-dnation to water supplies through ranking water resource protection districts by
                  sensitivity or vulnerability to contamination. Intermediate protection zones should be considered
                  as in the "zoned approach" recommended in this study, where more stringent land use controls could
                  be implemented. Ibis would allow for very stringent land use controls in close proximity to the
                  wells and in the recharge area with less stringent controls required over the wellhead protection
                  area.


                  For More Information

                  Mr. Allan Trefry, Manager, Department of Environmental Resources, Palm Beach County, Florida,
                  (407) 3554011.



                  COMPREHENSIVE MONITORING PROGRAMS


                  State of Rhode Island:
                  Salt-pond Watchers, Watershed Watch

                  Water quality monitoring has typically been left to professionals, but a recent upsurge in citizen
                  monitoring groups across the nation may soon change that approach. Citizen monitoring groups are
                  active across the nation in carrying out the otherwise expensive routine water sample collection.
                  Their efforts provide water resource scientists and mangers with a previously unavailable,
                  extensive, continuous water quality record for a variety of water resources.

                  Two citizen monitoring groups are currently collaborating with the University of Rhode Island
                  (URI) in monitoring water quality in surface water bodies. The Rhode Island Salt Pond-Watchers
                  is a group of over 100 senior citizens and other volunteers who regularly collect water quality
                  samples for analysis from coastal ponds. Some analyses are carried out in the field with simple
                  kits while others are performed at university, state, or federal laboratories. Samples are collected
                  for nine months of the year, when the ponds are not frozen over.

                  Pond Watchers receive training in water quality sampling methodology to ensure that the data
                  collected can be used for a wide range of purposes including:

                       ï¿½ on-going formal monitoring;
                       e early warning (to alert local or state authorities to a problem);
                       ï¿½ public health and shellfish monitoring.

                  The Rhode Island Department of Environmental Management was initially skeptical about the
                  value of the volunteer monitoring program, but has since reversed its official stand and has begun
                  exploring options for collaboration. Using funds from an EPA grant, DEM is in the process of
                  recruiting a statewide volunteer monitoring program coordinator.

                  URI works with a similar group, named Watershed Watch, which focuses on freshwater ponds and
                  lakes throughout the state. The Watch coordinates roughly 120 volunteers from land alliances,
                  land trusts, town conservation committees, and watershed councils. After undergoing one indoor and
                  one outdoor training session, the volunteers collect water quality measurements between May and
                  October of each year. Volunteers measure lake transparency using a Secchi disk every week, collect
                  samples for chlorophyll A concentration measurements, and take samples of water three times a


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                   year for chemical analyses. The analyses include measurements of nitrogen, phosphorus,
                   alkalinity, pH, magnesium, and calcium. Volunteers also collect on-site measurements of dissolved
                   oxygen every two weeks from ponds deeper than five meters.

                   The samples are forwarded to a university laboratory for analysis. A staff member and one
                   graduate student are funded through the university's cooperative extension program. The baseline
                   monitoring data are compiled and analyzed by the Watershed Watch university staff, who
                   prepare an annual report.

                   Watershed Watch also conducts shoreline surveys. Volunteers walk stretches of lake or river reach
                   shores and note the presence of any dumped materials, odors from tributaries or other surface
                   waters, bank erosion, etc. The information is entered into the program's Geographic Information
                   System database for analysis.

                   General Applicability to the Eastern Shore of Virginia

                   Volunteer water quality monitoring programs could provide the Counties with regular, up-to-date
                   water quality data for its priority ground water recharge protection areas. One possibility is to
                   develop a collaboration with the University of Virginia which would offer trained chen-tical
                   analysis and sampling program development expertise.

                   For More Information


                   Salt Pond Watchers
                   Ms. Virginia Lee, Coastal Resources Center, University of Rhode Island, Narragansett, Rhode
                   Island, (401) 792-6224.


                   Watershed Watch
                   Dr. Art Gold, Department of Natural Resources, University of Rhode Island, Narragansett, Rhode
                   Island, (401) 792-2903.

                   EPA Guidance Manual for States to Use Volunteer Monitoring.





















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1                                           10
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                    SEMON 10 - CONCLUSIONS OF THE REPORT


                    The following serves as a summary of what is included in the body of the report, sections 1 through 9.

                    SECTION I - Introduction

                    This section contains an overview of the study and results, an executive summary, and a description of
                    the purpose of the project.

                    SECTION 2 - Water Resources on the Eastern Shore of Virginia

                    Ground water quality and quantity are of the utmost importance on the Eastern Shore of Virginia
                    because there are no other fresh water sources for drinking supplies. Ground water is derived from
                    precipitation that hits the land surface of the two counties. The water that does not evaporate or run-
                    off to small streams moves through the unsaturated zone of the soil and recharges the unconfined,
                    shallow Columbia aquifer. Most water in the Columbia aquifer flows laterally from the center of the
                    peninsula and discharges to the Atlantic Ocean and the Chesapeake Bay; a small portion of this
                    ground water contributes to the base flow of small streams. A fraction of water in the Columbia aquifer
                    continues migrating vertically down through a confining layer and reaches the Yorktown-Eastover
                    aquifers located beneath the Columbia aquifer.
                    The Columbia aquifer is primarily made of sands, with some clay and silt. The recharge rate from the
                    Columbia (unconfined) to the Yorktown-Eastover (confined) aquifer is estimated to be 0.10 feet per year.
                    Depending upon specific location, this figure may be higher or lower by a factor of two. The Yorktown-
                    Eastover aquifer has three layers separated by confining units. The layers are referred to as the upper,
                    middle, and lower Yorktown-Eastover aquifers. These permeable layers are composed of coarse, shelly
                    sands and range in thickness from 10 to 120 feet. The confining units are between 10 and 70 feet thick.
                    Since most of the ground water flows from the Columbia aquifer to the coasts, it is the water that is
                    recharged from the center of the peninsula that reaches the Yorktown-Eastover aquifer. This area on
                    the spine is later identified as an important area to protect.
                    Total water use was calculated for the Eastern Shore of Virginia. Currently, agriculture is the biggest
                    water user in the two counties. In Accomack County, agricultural water withdrawals range from 6.04 to
                    6.86 million gallons per day (MGD), and in Northampton the range is 1.94 to 5.17 MGD, largely
                    depending on the rainfall that year. Farmers use a combination of ground water from wells and from
                    dug ponds, and surface water from dammed creeks for irrigation, so it is difficult to detern-tine the
                    impact of agriculture on specific aquifers. Public water supplies currently use 1.2 to 1.5 MGD, and are
                    permitted to withdraw a total of 4.2 MGD. Industrial facilities are permitted for 10.7 MGD, but
                    currently use water ranging from 3.1 to 3.4 MGD. These permitted facilities withdraw water from the
                    Yorktown-Eastover aquifer. It is estimated that private homes use between 1.7 and 2.3 MGD, mostly
                    from the Columbia aquifer, and non-community and non-transient, non-community public water supply
                    facilities withdraw approximately 0.14 MGD. Chicken watering requires 0.234 MGD.


                    SECTION 3 - Contamination Threats

                    Several land uses pose a threat to the ground water in the Columbia aquifer. Because contaminants are
                    discharged to the land or surface waters, the Columbia aquifer would be the first ground water source to
                    become contarridnated. The ground water systems are interconnected, and contan-tination could, after
                    time, reach the confined Yorktown-Eastover aquifer system. Potential sources of contamination were
                    identified and quantified for the Eastern Shore of Virginia. They are as follows:


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                    Public Sewage Systems - Only the three towns of Onancock, Cape Charles, and Tangier Island have
                    public sewage, and these serve less than 4,000 people.

                    On-site septic systems Septic systems are the most common form of household wastewater disposal in
                    the area. It is estimated that 12,105 septic systems exist in Accomack County, and 5,008 are located in
                    Northampton.

                    Permitted discharges and mass drainfields - Facilities that discharge wastewater from a point source
                    to surface waters must obtain a permit. There are 55 of these in the two counties. In addition there are
                    49 facilities that dispose of wastewater through mass drainfields, which are large septic systems.

                    Aocultural fertilizers - Agricultural practices apply 5.5 million pounds of fertilizers per year.

                    Pesticides - Many different pesticides are used on different crops against different pests. Quantities of
                    pesticides used are not reported. Thus, there is no way of determining how much of a threat pesticides
                    are to the ground water.

                    Animal wastes - With a 1990 chicken population of 21 n-dllion birds, there were 21,000 tons of chicken
                    manure produced. The manure is used to fertilize crop land. A natural mortality rate of 5% accounts for
                    the disposal of 1.8 million pounds of dead birds per year.

                    Underground storage tanks - There are 1,154 storage tanks on the Eastern Shore of Virginia. Of those,
                    684 (59%) are older than 15 years, and have a potential to leak. To date, 41 have been reported as
                    leaking.

                    Toxic chemicals - The Eastern Shore does not have many industrial facilities. There are several
                    companies that use toxic chen-ticals, and these are listed in Tables 3-7 and 3-8.

                    Solid waste - There are two public landfills in Accomack County, and one in Northampton County. The
                    Northern Landfill in Accomack County is located on the spine recharge area (Zone 2 defined in section
                    5), which could be dangerous for the water supply should there be a leakage accident. The landfill is
                    equipped with liners and runoff containers, and should not be a problem.

                    Septage disposal - There are three lagoons in the two counties owned by private companies. They are
                    unlined and are a threat to the ground water supply. One, in particular, is located on the spine recharge
                    area.



                    SECTION 4 - Existing Land Use

                    Accomack and Northampton Counties have Comprehensive Land Use Plans and Zoning Ordinances that
                    cover all land under jurisdiction of the County. The Comprehensive Plans represent development
                    policy, and as such are not legally enforceable. Twelve incorporated towns have growth plans and
                    zoning ordinances separate from the Counties.

                    In Accomack County, current zoning for agricultural and residential land would allow for dense
                    development to take place. In that case, it is possible that sufficient space required for a septic system
                    and drainage field would be lacking. Accomack has a single residential district that can accommodate
                    single family and.multi-fan-dly housing. There are no n-dnimum lot sizes for industries, which would
                    also potentially create a high density situation.



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                  Northampton County agricultural districts allow for a larger minimum open space potential than in
                  Accomack. Residential districts are more detailed in the number and type of housing units permitted
                  and the conditions under which units are pern-dtted. Single fan-dly districts require larger lots than in
                  Accomack County, but the primary building can take up as much as 66% of the lot (compared to 30% in
                  Accomack), which leaves less space for septic systems.

                  Both counties have a significant number of approved subdivisions which are as yet undeveloped. Many
                  of the land uses are allowed by right, meaning that permits and reviews by each county are not required
                  to determine whether the development will have an impact on ground water use or quality. The review
                  process may need strengthening in cases where potentially harmful uses are proposed.
                  The Chesapeake Bay Preservation Act is summarized in this section. The Act contains provisions for
                  three general land categories: Resource Protection Areas (RPA), Resource Management Areas (RMA),
                  and Intensely Developed Areas (IDA). Descriptions of each area is as follows:

                      RPA -Defined as the land at or near the Bay which can protect water quality. If disturbed, water
                      quality will be degraded. An RPA must have a buffer zone. Only redevelopment and water-
                      dependent development can take place within an RPA.

                      RMA - An RMA is the land which protects an RPA. Any development which is permitted by local
                      zoning can take place within an RMA.
                      IDA_7Significant development is allowed in, or pre-existed in an IDA. If an area has already been
                      developed, an IDA may be located within an RPA or and RMA.

                  All local governments are to have enacted local programs in accordance with the Chesapeake Bay
                  Preservation Act by November, 1991. Locally prepared programs must meet general performance
                  criteria, all of which relate to the ultimate use and condition of the ground water. Northampton
                  County incorporated its program into a Draft Comprehensive Plan in 1990, and drafted an overlay
                  zoning district. Accomack County has also drafted an overlay zoning district which is being assessed by
                  the County Board of Supervisors. In both counties, the attention has been paid to the requirements for
                  RPA's. There is less mention of RMA's, and no requirements are included for IDA's in either county's
                  draft.



                  SECTION 5 - Delineation of Ground Water Supply Management Areas

                  Ground Water Supply Management Areas consist of three zones, and are summarized below.

                      Zone 1: 200-foot radial distance around each well.
                      This prevents contaminants from moving into the aquifers via a poorly constructed well or bad seal.
                      Zone 1 also serves as protection against accidental spills near the wellhead.

                      Zone 2: Hydrogeologic boundaries based on recharge areas.
                      This area was determined based on a recharge rate of 9 inches per year to the Columbia Aquifer.
                      Using permitted pumping rates, the land area required to balance that volume of withdrawal with
                      the rate of recharge was calculated. Calculations determined that a width of 5,000 feet along the
                      spine is the boundary of Zone 2.

                      Zone 3: Hydrogeologic boundaries using contributing areas of flow.
                      Zone 3 is based on ground water divides created by pumping patterns under permitted conditions.
                      There are large drawdown areas on the peninsula because of a moderate to low transn-dssivity



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                         (water travel through the aquifer) within the Yorktown-Eastover Aquifers. Thus, Zone 3 covers
                         virtually the entire peninsula, and is split into five different Wellhead Protection Areas (WPA).

                     The five WPA's are summarized according to wells, discharges, landfills, lagoons, and acreage. WPA
                     A includes the Chincoteague area; WPA B - Holly Farms (Tyson Foods); WPA C - Perdue; WPA D -
                     Exmore; WPA E - Cape Charles.


                     SECTION 6 - Water Budget/Balance

                     Columbia Aquifer - The water budget approach indicates that there is 17 inches of water recharged to
                     the Columbia Aquifer per year, assun-dng 50% runoff. With an area of 400 square miles of land, the
                     recharge to the Columbia aquifer is 324 MGD. With so much water being recharged to the Columbia
                     aquifer, there is little concern over the quantity of available water in this aquifer.

                     Yorktown-Eastover Aguifer The rate of recharge to the Yorktown-Eastover aquifer system is slow, but
                     the volume of water entering the confined system is large. Since recharge only occurs in the central
                     portion of the peninsula, the spine, the area of recharge is only 200 square miles. With a recharge rate
                     of 0.10 feet per year, approximately 11 MGD are being recharged to this confined aquifer. Permitted
                     withdrawals for industrial and public water supply currently exceed that amount, and are at 15.6 MGD.
                     This is independent of any withdrawals by agriculture or private facilities. Serious consideration
                     should be taken to evaluate the quantities allowed to withdraw from the Yorktown-Eastover aquifer
                     system.

                     Salt Water Intrusion - Salt water can intrude laterally, vertically through the confining layers, or
                     through upward vertical migration (upconing). If a well is pumped at too high a rate, salt water
                     upconing will reach the well and contaminate the supply source. To prevent this from happening, it is
                     best to maintain a stable pumping rate, rather than one of seasonal fluctuations. In general, water that
                     has more than 250 mg/I of chloride tastes salty, and is unacceptable for drinking. In all likelihood,
                     this is probably happening now at the Lower Yorktown-Eastover Aquifer, but since public and
                     industrial wells are screened at three layers, the salt content is diluted before it reaches the faucet.


                     SECTION 7 - Buildout/ Developable Lot Analysis

                     The purpose of the buildout analysis is to evaluate the impacts of existing and potential land uses on
                     ground water quality. For this, existing land uses within the spine recharge area (Zone 2) were
                     assessed. According to current land use plans, potential development within the spine was then
                     calculated. It was detern-dned that, if the area within Zone 2 was developed to its full potential with
                     single farrdly houses, then the number of dwelling units in the spine alone would exceed the number
                     currently existing in all of the two counties.


                     SECTION 8 - Nitrogen Loading

                     This section explains the potential dangers from nitrate-nitrogen contan-driation, including "blue baby
                     syndrome" and possibly cancer. The current EPA standard limit for nitrate-nitrogen in water is 10
                     rrdlligrams per liter (mg/1). Sources of nitrate-nitrogen are sewage, fertilizers (agricultural and lawn),
                     animal wastes, landfills, septage lagoons, pavement and roof runoff, industries, and precipitation. All
                     inputs from these sources were calculated for the Eastern Shore of Virginia, and added together to
                     predict the current average nitrate-nitrogen concentration in the ground water. This was found to be 2.0
                     mg/I in Accomack County and 1.9 mg/I in Northampton County. This falls well below the EPA


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                  standard, but being an average for the area, this does not mean that there are no problem sites in either
                  county. The largest contributors of nitrate-nitrogen are agriculture and septic systems.

                  Existing water quality tests show low nitrate-nitrogen concentrations, with several isolated high
                  readings. There are problems in some areas, especially in the Columbia (shallow) aquifer.

                  Results from the buildout analysis were used to predict average nitrate-nitrogen concentrations under
                  buildout conditions. These figures reflect the future concentrations if the land area in Zone 2 is built
                  according to current land use plans. The HWH model predicts that WPA B would experience elevated
                  nitrate-nitrogen concentrations of 13.5 mg/l.


                  SECnON 9 - Case studies and Their Applicability To The Eastem Shore of Virginia

                  A number of case studies are summarized in this section in order to illustrate different water resource
                  protection strategies which may potentially benefit the Eastern Shore's efforts to protect its surface
                  and ground waters. The subjects addressed in this section are agricultural influences, on-site waste
                  disposal, surface water, hazardous materials, and monitoring programs.































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                   SECTION 11: RECOMMENDATIONS


                   The Eastern Shore of Virginia is situated over a very valuable ground water resource that is a sole
                   source of water supply to the inhabitants of Accomack and Northampton Counties. Ground water is the
                   only significant supply source for public water withdrawals, private on-lot wells, industrial water use,
                   and agricultural irrigation. The future land use plans for both counties are to maintain a low density
                   pattern of development with growth occurring in the established villages and population centers.
                   This study has identified the primary recharge area to the confined Yorktown-Eastover aquifer which
                   is the principle source of water on the Eastern Shore. Protection of the excellent water quality in this
                   aquifer will require the implementation of many actions designed to maintain the water quality,
                   prevent against over use of the aquifer and provide for the future water needs to accommodate growth
                   on the Eastern Shore of Virginia.

                   The shallow Columbia aquifer has experienced water quality degradation in a number of areas. Since
                   this aquifer is used primarily for on-site private water use, recommendations are presented to ensure
                   that this planned use can continue. The Columbia aquifer also provides recharge to the confined
                   Yorktown-Eastover aquifer system. Maintaining a high water quality in the Columbia ensures that
                   land use threats to the confined aquifer will be minimized.

                   Recharge estimates to both the Columbia and Yorktown-Eastover aquifers indicate that in combination
                   there is sufficient water quantities to meet both the current and future water demands. In order to
                   supply water for intended uses, proper water management is required in conjunction with protection of
                   the water quality.

                   These recommendations for ground water protection and management will also apply to Tangier Island.
                   Land use conditions are similar on Tangier Island, however, water is withdrawn from a much deeper
                   aquifer.
                   Examples of most of the following recommendations that require local regulations are on file with the
                   Accomack-Northampton Planning District Comn-tission.

                   Recommendations for Water Quality and Quantity Protection

                   #1: Water Conservation for Major Industrial Water Users

                   The Ground Water Study Committee should pursue with major industrial users, fresh water
                   conservation possibilities. These possibilities n-dght include the use of lower quality water for effluent
                   dilution, and the reduction in wastewater flows from treatment plants.

                   #2: Overlay Protection Zoning District. - Future Activities

                   Based upon the Wellhead Protection Area Map prepared by HWH, and the delineation of wellhead
                   protection areas and recharge areas to the Yorktown-Eastover aquifer, the Counties should adopt a
                   zoning overlay ground water protection district. This action would apply only to future activities and
                   not have any effect on existing facilities and development. The delineated protection zones should be
                   dealt with in a progressively more relaxed fashion in terms of land use restrictions. Zone 1 is a 200-foot
                   radius around pumping wells, Zone 2 is the spine recharge area to the Yorktown-Eastover aquifer, and
                   Zone 3 is the delineated wellhead protection areas.




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                         -   The area encompassing Zone 1 should have strict prohibitions excluding virtually all future
                         potentially harmful activities within the 200-foot radius. The only activities that should be
                         permitted within Zone 1 are passive recreation and maintenance of the wellhead itself. All
                         pesticides, insecticides, herbicides, all storage of potentially dangerous material (salt, chen-dcals,
                         petroleum products) should not be permitted within Zone 1.

                         -   Zone 2 should have land use restrictions commensurate with the delicate role it 12lays in
                         recharging the Yorktown-Eastover aquifer. uch restrictions would be less onerous than those of
                         Zone 1, but would include prohibiting the future siting of major polluting activities (landfills,
                         septage lagoons, etc.) and requiring special permits based on performance standards for others
                         (underground fuel storage tanks, toxic and hazardous materials, etc.)

                         -  Zone 3 should have the least restrictive land use Legulations, rel3ing heavily on 12ubli
                         awareness to avoid contamination of the aquifers on the Eastern Shore. It should be remembered
                         that this area also recharges the Yorktown-Eastover aquifer and all land use activities should be
                         managed with protection of ground water quality in mind. The ground water resources are a sole
                         source of supply to the residents of the Eastern Shore and as such should be protected and managed.

                    #3: Restrict New Mass Drainfields in the Recharge Area ( Zone 2)

                    The combined use of large septic systems by several businesses, homes, or industries provides a major
                    point source of nitrogen loading and bacterial contamination to the Columbia Aquifer. This waste water
                    disposal technique should, for the most part, not be allowed for future development in Zone 2. Overlay
                    zoning can be employed to restrict mass drainfields within Zone 2. Any new mass drainfields installed
                    within Zone 2 should prove that they can manage the facility and meet treatment levels allowed
                    within that area. A performance standard could be established in the overlay zoning district for mass
                    drainfields, or site plan reviews could incorporate the same requirements.

                    #4: Review and Revise Counly Zoning and Subdivision Regulations

                    Accomack and Northampton Counties should revise their current zoning and subdivision regulations to
                    incorporate ground water quality and quantity protection. Most of the assessment of land use threats
                    conducted during this study point to the need to control density, location, and the pattem of
                    development. As zoning and subdivision regulations are revised, many of the suggested
                    recommendations can be incorporated into the formal process of revisions.

                    #5: HgQuire the Registration of Underground Storage Tanks Storing Volumes Less Than the State
                    Rgq,uirements
                    The Virginia Water Control Board currently regulates tanks which store more than 1,100 gallons of
                    product. In order to adequately assess the threat from existing tanks, the counties should establish a
                    registration program for all tanks storing less than 1,100 gallons. At this point, only registration of
                    tanks is recommended. When ever possible, above-ground storage tanks should be used in place of
                    underground tanks.

                    #6: Inco=rate Ground water Protection Into Site Plan Review

                    Both counties should revise their zoning ordinances to require that ground water protection be
                    considered in all major site plan reviews. This will require developers of commercial and industrial
                    sites to identify and mitigate potential negative impacts to ground water quality and quality from
                    their development.



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                  #7. Private Well Ordinance


                  Both counties should develop a health ordinance or revise subdivision regulations to require a minimum
                  300 foot separation distance in a downgradient ground-water flow direction for private wells finished
                  in the Columbia aquifer from septic systems. Private on-site wells will continue to be a major water user
                  on the Eastern Shore. Approximately 2 million gallons per day are withdrawn by private wells. In
                  addition, where ever possible, new private wells should be finished in the Yorktown-Eastover aquifer
                  to to eliminate the threat of nitrate contan-driation in the shallow aquifer. Water quality testing for
                  nitrates for all new wells should be required prior to approval for use.

                  #8: Encourage Agdcultural Nutrient Management Plans

                  The Soil Conservation Service, County Extension Agents, and the Eastern Shore Soil and Water
                  Conservation District should continue their program of assisting farmers in developing nutrient
                  management plans. These plans should incorporate: soil nutrient testing; crop productivity
                  recommendations; animal waste management; and fertilizer use record keeping. Especially important
                  in Accomack County is the control of chicken waste products and disposal of dead chickens to minirrdze
                  impacts on surface water and ground water resources. Government programs are in general developed to
                  assure the general population adequate surplus food at minimum cost. As a result, farmers cannot pass
                  along increased costs of production. As a result and in view of preliminary data concerning the
                  submitted soil samples, it is recommended that cost-share assistance be considered, with time by the
                  two counties and/or state, for soil testing through the Eastern Shore Soil and Water Conservation
                  District.


                  #9: Implement Chesal2eake Bay Program

                  Both counties should implement the required provisions of the State of Virginia's Chesapeake Bay
                  Act. The Act contains many provisions that will not only protect the quality of surface water drainage
                  to the Chesapeake Bay, but also the ground water that ultimately discharges to the Bay.
                  Specifically, the following provisions of the Act should be incorporated into local regulations:
                  mandatory 5 year pump-out of septic systems; required reserve leach fields for septic systems; new
                  development site plan review to include water quality protection; restrictions on impervious cover;
                  stormwater quality management; and the protection of valuable wetlands.

                  Recommendations for Water Quantity Management

                  #1: Revise State Ground Water Act and Regulations

                  A revision to the State Ground Water Act ( Chapter 3.4 of the State Water Control Board Statutes)
                  which would allow re-authorizing of ground water withdrawals on the Eastern Shore is necessary to
                  ensure that overuse of the confined aquifer does not result in saltwater intrusion, well interference, or
                  create major drawdowns. The current permitted volumes may exceed the recharge rates to the
                  Yorktown-Eastover aquifer as modelled by HWH.

                  #2: Eastern Shore Water Management District

                  Accomack and Northampton counties should explore the possibility of forn-ting a water supply district
                  or water authority to centralize public and industrial water uses under one regulatory agency. There are
                  currently several dozen active water withdrawal permits on the Eastern Shore. This promotes
                  incomplete data bases, complicated administrative tracking and management and poor utilization of
                  the ground water resource. The purpose of this recommendation is to encourage the consideration of a
                  single water supply and management authority, especially to cover the geographic area of the spine


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                   recharge zone. The Water Management District would be authorized to: plan for future water supply
                   needs; obtain necessary state and federal permits; install and operate new public water supply systems
                   that could service new areas; provide for the consolidation of the many systems that are currently in
                   operation; and promote proper utilization of the ground water resource.

                   As development continues on the Eastern Shore and more withdrawal permits are requested, the need
                   for centralized management wfil become more apparent.

                   #3: Water OuantijX Management -Existing and New Water SuMly Sources

                       0 New water supply sources that tap the Yorktown-Eastover aquifer should be located in the
                       central pgrtion of the Eastern Shore pgninsula. This approach will minimize both lateral intrusion
                       from salt water and vertical intrusion of salt water through confining layers. It will also simplify
                       wellhead and aquifer protection since the position of the recharge area will not be skewed to one
                       side or the other of the peninsula.
                       :
                           New water sul2pjy sources should be screened in the u12Rgr and middle Yorktown-Eastover.
                        voiding the lower Yorktown-Eastover. Screening only the higher layers minimizes many of the
                       problems of upconing of high chloride content water.

                       0 Wellfields rather than single wells to produce large volumes of water should be encouraged. A
                       series of wells each pumping a moderate amount of water will create less upconing, less well
                       interference and less lateral intrusion that one or two high volume wells.

                       0 New and existing water supply users should be encouraged to j2umj2 at moderate volumes on an
                       extended basis and to use surface storage (tanks, lined ponds) rather than pumping hard for short
                       intervals to meet peak demands. The continual pumping of moderate volumes will allow a smaller
                       upcone to develop and to stabilize, eliminating much of the problem of salt and fresh water mixing
                       that occurs with intermittent pumping. A progressively enlarged mixing zone between fresh and
                       salt water will promote the intrusion of high chloride water into the fresh water zone.

                       s The use of water supplies from the unconfined Columbia aquifer should be encouraged in
                       situations where water -quality is less of a concern. The Columbia receives considerably more
                       recharge than the Yorktown-Eastover aquifer, and while its water quality is sometimes marginal
                       as a potable water supply, the quality is perfectly adequate for a number of industrial, agricultural
                       and even domestic uses. High volume users of water that do not need water of drinking quality
                       standards should be urged to use the Columbia as a source where adequate flows can be achieved.

                   #4: Mandato@y Repgrting of Large Agricultural Water Withdrawals
                   Agricultural water withdrawals have been identified as the largest single source of water use on the
                   Eastern Shore. Yet very little is known about how this water is used and from which aquifer it is
                   obtained. State Water Control Board Regulations currently require that irrigators which withdraw
                   more than 1 million gallons/day on the average for any month report this use to the VAWCB. The
                   Ground Water Committee should develop public educational materials to inform irrigators of the need
                   to collect accurate information on their water use.

                   #5: Consider Permitting of Large Agricultural Water Withdrawals
                   If after review of the reporting of large agricultural water withdrawals it becomes apparent that these
                   withdrawals are significant contributors to the total withdrawal from the Yorktown-Eastover aquifer,
                   the Virginia State Water Control Board should be encouraged to regulate the amounts and locations of


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                   existing and future agricultural withdrawals. This will provide for better management and control of
                   withdrawals from the aquifer.



                   #6: Protect QWn Space in the Spine Recharge Area

                   Local governments on the Eastern Shore should seek to acquire public open space in the Zone 2 Recharge
                   Area. This can be accomplished with the assistance of public conservation groups such as The Nature
                   Conservancy, which has already acquired most of the coastal marsh areas of the Eastern Shore. Public
                   land ownership will ensure the protection of water quality and allow for the control and development
                   of prime water supply development sites.


                   General Recommendations

                   #1: Implement a Land Use/Water Quality Data Base

                   The A-NPDC should consider the establishment of a centralized water quality data base for all water
                   use on the Eastern Shore. Experience from the study identifies the need for centralized data to continue
                   the planning and management of the the ground water resource. Data collection and synthesis was very
                   time consuming and could greatly reduce future planning and analysis costs with the development of a
                   central repository of water quality information. In addition, land use information could also be
                   centralized and managed by the A-NPDC to allow the agency to assist the counties in implementing
                   land use controls for water resource protection.

                   #2: Public Education on Ground water

                   The Eastern Shore of Virginia Ground Water Study Committee should continue to develop materials
                   and provide information to the public on the importance of the ground water resource on the Eastern
                   Shore. Additional publications, meetings, forums, etc. should be planned to encourage support for
                   ground water protection and management. Continued support for research conducted by the US
                   Geological Survey should be a primary activity for the Cornmittee. This research will form the basis
                   for many future decisions regarding ground water management.

                   Continued Research and Investigation

                   #1: Investigate the Nature of Recharg!2 to the Yorktown-Eastover System

                   The rate, volume, timing and distribution of recharge from the unconfined Columbia aquifer to the
                   Yorktown-Eastover aquifer remains a focal point to the water supply problems on the Eastern Shore. If
                   the rate of recharge is as low or lower than has been modelled analytically in this study, and if the
                   area over which recharge occurs is smaller than the 200 to 300 square miles used, the issue of water
                   quantity in the Yorktown-Eastover aquifer becomes even more important than has been argued here.
                   Because this is a key issue, additional work should be considered to attempt to better quantify the
                   recharge component of the hydrologic cycle. It may be possible, for example, to employ the USGS finite
                   difference model designed to model salt water intrusion, currently in review (Richardson, in press),
                   using that database as a means to better quantify the rate, volume and areal distribution of recharge to
                   the confined system. Results from the Richardson report should be incorporated into the Protection and
                   Management Plan when this report is available.

                   #2: Research Dilute Salt Water Issues



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                    Salt water movement into both the Columbia and Yorktown-Eastover aquifers is a very important and
                    real threat on the Eastern Shore. Additional study is needed to quantify the limits of salt water in the
                    250 milligrams per liter range. This information is necessary to determine the lin-dtations that may
                    need to be set on individual water withdrawals.

                    #3: Investigate the Character of Pleistocene Paleochannels on the Eastern Shore

                    A major focus of continued research should focus on the paleochannels that cross the Eastern Shore.
                    These could prove to be major sources of supply to the two counties, but their use would have to be
                    coupled with a solid understanding of the geometry and flow patterns involved. It is likely that the
                    deep central portions of the channels possess sands and gravels from the depositing stream that formed
                    the channel, deposits that probably would have good permeability and would make excellent aquifers.
                    However, development of such materials would have to be done carefully to avoid both upconing and
                    vertical intrusion of salt water. Since the permeable deposits would be at the bottom of the channels,
                    they would be closest to underlying salt water and subject to upconing problems that could ruin an
                    otherwise good well. Since the channels are documented as connecting to the mainland, passing
                    beneath Chesapeake Bay (Colman and others, 1990), a substantial portion of the channels lie beneath
                    salt water. Excessive pumping of a well located in a paleochannel on the Eastern Shore peninsula could
                    result in contamination from salt water intruding vertically in response to the gradients created by
                    pumping-

                    #4: Evaluate Pesticides Use on the Eastern Shore

                    The impact of pesticide use on ground water quality on the Eastern Shore should be studied. Currently,
                    information is not available to accurately assess this potential source of contarridnation. The VA
                    Department of Agriculture and Consumer Services, Office of Pesticide Management should be contacted
                    to provide assistance in this effort. Since agriculture is planned as the predon-dnant land use in the
                    future, this effort should be a priority for future investigations.

                    #5: Agricultural Nutrient Management Research

                    Additional research should be conducted on the specific nature of agricultural nutrient use and impacts
                    on the water resources of the Eastern Shore. This study utilized general information regarding nitrogen
                    application rates, leaching potential, chicken litter disposal and use, and dead chicken disposal. More
                    specific information is necessary on: actual nitrogen application rates and amounts used by crop types;
                    nitrogen leaching rates by soil types found on the Shore: an accurate assessment of chicken litter use and
                    disposal of dead chickens; quantification of the success of nutrient management plans in reducing
                    nitrogen use and loss; fate and transport of nitrogen in the ground water system (Columbia and
                    Yorktown-Eastover).


                    #6: Revise Nitrogen Modelling

                    Nitrogen is a very good indicator of overall ground water quality. The nitrogen model used in this study
                    to assess land use impacts should be revised as more detailed information becomes available. Virginia
                    Tech is currently conducting a study of nitrogen contamination in the ground water of the Eastern Shore.
                    This new data can be used to update and verify the results of the model. The model is designed to allow
                    for easy revisions and scenario testing. The model can be used in planning new development and in the
                    assessment of zoning changes.





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          Regulated Contaminants

          The following is a list of drinking water contaminants for which the U.S. Environmental Protection Agency is setting health-based
          standards (Maximum Contaminant Level Goals, or MCLGs) and enforceable standards (Maximum Contaminant Levels, or MCLs)
          For some contaminants, there is also a Secondary Maximum Contaminant Level (SMCL), a level set to prevent taste or odor
          problems. Unless otherwise indicated, the levels presented are milligrams per liter (mg/1). For some contaminants, the MCL is a
          prescribed treatment. See "Setting the standards for safe drinking water" and contaminant descriptions for more information.

          Contaminant                                                MCLG                                 MCL                    SMCL                 Interim

          acrylamide                                                 0                                    .005% dosed at 1 mg/l
          adipates2                                                  O.S                                  O.S
          alachlor                                                   0                                    0.002
          aldicarbl                                                  0.01                                 0.01
          aldicarb sulfonel                                          0.04                                 0.04
          aldicarb sulfoxidel                                        0.01                                 0.01
          alpha particle acitity (gross7)                                                                                                             15 pCi/l
          antimony,                                                  0.003                                0.01 or 0.005
          arsenic4                                                                                                                                    0.05
          asbestos                                                   7 million fibers/liter
          atrazine                                                   0.003                                0.003
          bariuml                                                    5                                    5                                           1
          benzene                                                    0                                    0.005
          beryllium2                                                 0                                    0.001                  4 mrem/yr
          beta particle and photon radioactivityr-
          cadmium                                                    0.005                                0.005                  0.01
          carbofuran                                                 0.04                                 0.04
          carbon tetrachloride                                       0                                    0.005
          chlordane                                                  0                                    0.002
          chlorobenzenel                                             0.1                                  0.1                    0.1
          chromium                                                   0.1                                  0.1                                         0.05
          copperl                                                    1.3                                  1.3
          cyanide2                                                   0.2                                  0.2
          dalapon2                                                   0.2                                  0.2
          dibromochloropTopane (DBCP)                                0                                    0.0002
          o-dichlorobenzene                                          0.6                                  0.6                    0.01
          p-dichlorobenzene                                          0.075                                0.075                  0.005
          1,2-dichloroethane                                         0                                    0.005
          1,1-dichloroethylene                                       0.007                                0.007
          cis-1,2-dichloroethylene                                   0.07                                 0.07
          trans-1,2-dichlOToethylene                                 0.1                                  0.1
          2,4-dichlorophenoxyacetic acid (2,4-D)                     -0.07                                0.07                                        0.1
          1,2-dichloropropanel                                       0                                    0.005
          dinoseb7                                                   0.007                                0.007
          dioxin (2,3,7,8-TCDD)2                                     0                                    0.00000005
          dig t2                                                     0.02                                 0.02
          endothaI12                                                 0.1                                  0.1
          endrin2                                                    0.002                                0.002                                       0.0002
          epichlorohydrin                                            0                                    .01 % dosed at 20 mg /I
          ethylbenzene                                               0.7                                  0.7                    0.03
          proposed May 1989; may be finalized December 1990                      2proposed July 1990                3to be proposed February 1991


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         Contaminant                                                      MCLG                            MCL                   SMCL                 Interim


         ethylene dibromide                                               0                               0.00005
         fluoride                                                         4                               4                     2
         Giardia lamblia                                                  0                               treatment
         glyphosate2                                                      0.7                             0.7
         heptachlor                                                       0                               0.0004
         heptachlor epoxide                                               0                               0.0002
         hexachlorobenzene2                                               0                               0.001
         hexachlorocyclopentadiene2                                       0.05                            0.05                  0.008
         leadl                                                            0                               0.005                                      0.05
         Legionella                                                       0                               treatment
         lindane                                                          0.0002                          0.0002                                     0.004
         mercury                                                          0.002                           0.002                                      0.002
         methoxychlor                                                     0.04                            0.04                                       0.1
         methylene chloride2                                              0                               0.005
         nickel2                                                          0.1                             0.1
         nitrate (as N)                                                   10                              10                                         10
         nitrite (as N)                                                   1                               1
         pentachlorophenoll                                               0.2                             0.2                   0.03
         phthalales2                                                      0                               0.004
         picloram2                                                        0.5                             0.5
         polychlorinated biphenyls (PCBs)                                 0                               0.0005
         polycyclic aromatic hydrocarbons (PAhs)2                         0                               0.0002
         radium 226 and 2283                                                                                                                         5 pCi/l
         radon3
         selenium                                                         0.05                            0.05                                       0.01
         simazinel                                                        0.001                           0.001
         standard plate count                                                                             treatment
         styrene                                                          0.1                             0.1                   0.01
         sulfate2                                                         400 or 500                      400 or 500
         tetrachlOToethylenel                                             0                               0.005
         thallium2                                                        0.0005                          0.002 or 0.001
         toluene                                                          1                               1                     0.04
         total coliforms                                                  0                               treatment
         toxaphene                                                        0                               0.003                                      0.005
         trichlorobenzene2                                                0.009                           0.009
         1,1,1-trichloroethane                                            0.2                             0.2
         1,1,2-trichloroethane2                                           0.003                           0.005
         trichloroethylene                                                0                               0.005
         2,4,5-trichlorophenoxypropionic
                acid (Z4,5-TP)                                            0.05                            0.05                                       0.01
         turbidity                                                                                        treatment
         uranium3
         vinyl chloride                                                   0                               0.002
         viruses                                                          0                               treatment
         7daJ                                                             0.2                             0.2
         xylenes (total)                                                  10                              10                    0.02

         4to be dealt with separately                    5longer than 10 gm
         Source: What Do The Standards Mean?: A Citizens' Guide to Drinking Water Contaminants, VA Tech.



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                                                                APPENDIX B    I
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                                              Table B-1: 1990 U.S. Census Population Counts
                                                Accomack-Northampton Planning District

                                                                                                   people/units
               _Lgcality                           Population Counts         Housing Units          Density

               Accomack County                           31,703                   15,840                2.00

               Accomack Town                                466                      205                2.27
               Belle haven Town                             526                      245                2.15
               Bloxorn Town                                 357                      175                2.04
               Chincoteague Town                           3,572                   3,167                1.13
               Hallwood Town                                228                      115                1.98
               Keller Town                                  235                      107                2.20
               Melfa Town                                   428                      191                2.24
               Onancock Town                               1,434                     705                2.03
               Onley Town                                   532                      276                1.93
               Painter Town                                 259                      113                2.29
               Parksley Town                                779                      393                1.98
               Saxis Town                                   367                      192                1.91
               Tangier Town                                 659                      277                2.38
               Wachapreague Town                            291                      223                1.30
               Outside of incorporated towns             21,570                    9,456                2.28

               Northampton County                        13,061                    6,183                2.11

               Cape Charles Town                           1,398                     689                2.03
               Cheriton Town                                515                      246                2.09
               Eastville Town                               185                      94                 1.97
               Exmore Town                                 1,115                     528                2.11
               Nassawadox Town                              564                      227                2.48
               Outside of incorporated towns               9,284                   4,399                2.11

               A-NPD TOTAL                               44,764                   22,023                2.03

                                         Table B-2: Historical and Projected Population Figures

               Year                                1950     1960     1970      1980   1985     1990     1995     2000


               Population
               Accomack County                    33,832 30,635 29,004 31,268 31,200 33,000             33,300 34,000
                                                                                               31,130-          31,990'
               Northampton County                                   14,442 14,625 14,700       15,000   15,000   15,300
               A-NPD                                                43,446 45,893 46,500       48,000   48,300  49,300

               Sources: VSWCB Eastern Shore Water Supply Plan, 1988; Accomack County Comprehensive Plan,
               1989 (*- A-N PDC linear TMI model). Both used the following sources: US Bureau of the Census,
               Virginia Department of Health, Tayloe-Murphy Institute.






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                                LAWS AND REGULATIONS APPLICABLE TO THE STUDY



                   Virginia State Water Control Board Statutes. July 1. 1990
                   Chapter 3.1 - State Water Control Law Article 4. Regulation of Sewage Dischargr.1

                   All sewerage and sewage treatment operations are under joint supervision of the State Department
                   of Health and the Board. If a proposed facility will serve more than 400 people and if it has
                   potential for or actual discharge to state waters, owners shall file an application to the Board and
                   the State Department of Health for a certificate before any erection, construction, operation, or
                   expansion can occur. In 1977, owners and operators of sewerage systems and sewerage and industrial
                   waste treatment works conducted a survey in order to determine the physical, chemical, and
                   biological properties of discharge.

                   Vir&ia State Water Control Board Statutes, July 1. 1990 Chapter 3.4 - The Groundwater Act of 1973

                   The basic premise behind this act is that the right of water control belongs to the public, but in
                   order to ensure public welfare, safety, and health, provisions must be made for control of ground
                   water. The Board and the State Department of Health administers and enforces the provisions of
                   this chapter. Special care is taken to protect Groundwater Management Areas (GMA). The Board
                   will initiate a study if it is believed that in a certain area ground water levels are declining, two or
                   more wells are interfering, the ground water supply is or will be overdrawn, or the ground water is
                   or is expected to be polluted. Should an area be deemed a GMA, one must obtain a permit in order to
                   withdraw ground water from such area. No certificate is needed to withdraw from an area that is
                   not declared a GMA, nor for those withdrawing less than 300,000 gallons/month or for agricultural
                   or livestock purposes. The Board may establish regulations which will require only agricultural
                   withdrawal greater than 300,000 gallons/month to be reported.

                   VR 680-14-01 - State Water Control Board Regulations - Pollution Abatement Permit Regulation

                   This regulation sets guidelines for pretreatment programs, and identifies procedures and
                   requirements to be followed in connection with Virginia Pollutant Discharge Elin-tination System
                   (VPDES) and Virginia Pollution Abatement (VPA) permits issued by the Board pursuant to the
                   Clean Water Act or the State Water Control Law. Pern-dts are required for discharge of anything
                   that may alter state waters. Point sources are authorized by a VPDES permit, non-point by a VPA
                   permit. Any spills, unplanned bypasses, or non-compliance which may endanger state waters must
                   be reported by telephone within 24 hours. Animal feeding operations are subject to the VPA permit
                   program if they are considered concentrated (100,000 laying hens or broilers) or intensified (30,000
                   hens, broilers). Under this regulation, animal feeding operations (animals are stationed or fed on
                   premises for at least 45 days per year) shall maintain no point source discharge of pollutants to
                   state waters except in the case of a 25 year, 24 hour storm event.

                   VR 680-14-03 - State Water Control Board Regulations. Pollution Abatement Toxics Management
                   Regulation

                   The purpose of this regulation is to control the levels of toxic pollutants in surface waters
                   discharged from all sources holding VPDES or NPDES permits. It provides standards and
                   procedures to minimize or prevent any toxic discharge in levels dangerous to human health or the
                   environment. Whenever VPDES permits are issued or modified, the Board will determine whether
                   or not there is a need for toxics management. Toxics monitoring must be done if the discharge has
                   actual or potential toxicity, if the permitted works falls into the Industry Class, if the industrial
                   wastewater flow is greater than 500,000 gallons/day, if a Publicly Owned Treatment Works



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                    (POTW) discharges greater than 1 million gallons per day, or if a POTW undergoes a pretreatment
                    program.

                    State Water Control Board Regulations - Pollution Abatement Regulation No. 8. Sewerage
                    Regulations
                    These regulations were adopted jointly by the State Water Control Board and the State Board of
                    Health. They were set up in order to ensure that the design, construction, and operation of sewage
                    treatment works and sewerage systems are consistent with public health and water quality
                    objectives of the Commonwealth of Virginia. The regulations assist owners in preparation of an
                    application, plans, or data and lay the rules by which the Board will review and make decisions in
                    regards to the specifications and applications.

                    State Water Control Board Regulations - Water Supply Data VR 680-15-01. Water Withdrawal
                    RgRgifing

                    Under this regulation, water withdrawal information will be submitted to the Board for the
                    purpose of formulating and preparing plans and programs for the management of water resources in
                    the Commonwealth of Virginia. The data will also be available to local governments and local
                    interests to assist them in their own water supply planning. The regulation applies to every user
                    withdrawing ground water or surface water whose daily average withdrawal during any month
                    exceeds 10,000 gallons/day. It also applies to every user withdrawing ground or surface water for
                    the purpose of irrigating crops whose withdrawal exceeds 1 million gallons in any single month.
                    Industrial VPDES pem-dttees must report their source and location annually. Every nonexempt user
                    other than crop irrigators shall have installed and shall operate a gaging device . Crop irrigators
                    shall comply with measuring provisions by January 31, 1991. Every nonexempt user shall file with
                    the board a reporting form every January 31 of each year.. The information reported includes
                    source(s) and locations of withdrawal, cumulative volume of water withdrawn each month,
                    method of withdrawal measurement, and maximum day withdrawal. Crop irrigators shall comply
                    with reporting provisions by January 31, 1992

                    State Water Control Board Regulations - Groundwater Rules and Standards for Water Wells

                    So that equitable development and utilization of ground water is achieved in Virginia, these rules
                    and standards set forth the authority for controlling ground water. Essentially, these rules and
                    standards set provisions to prevent wells from becoming a source or channel for the entry of
                    pollutants or contaminants. Under the jurisdiction of this regulation are: registration statements,
                    construction and maintenance of wells, observational and abandoned wells, data and records, and
                    general requirements. Methods for testing well yield are described.

                    VR 680-21-M - State Water Control Board Regulations - Water Quality Standards

                    The State Water Control Law, Section 62.1-44.15(3), mandates the protection of existing high
                    quality state waters and also provides for the restoration of all other state waters to a condition of
                    quality which will allow all public uses: water-based recreation, public water supply, and growth
                    of balanced populations of fish and wildlife. In this regulation, water quality requirements for
                    surface waters and ground water are described and listed in tables in numeric limits and general
                    terms for specific physical, chemical, biological, and radiological characteristics of water. These
                    limits set the standards that must be met by all discharge applicants. Municipal and industrial
                    discharge mixing zones are viewed separately, and must not threaten recreation and wildlife use.
                    In addition, special standards for shellfish waters are set for the median fecal coliform value.
                    Extra precautions must be made in surface waters so that eating shellfish is not hazardous. The



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                  Board will convene a public hearing to talk about any proposal that would result in the
                  Department of Health condenu-dng shellfish beds.

                  Acknowledging that ground water quality varies in different areas, the Board has divided the
                  state into four physiographic provinces by which they establish different criteria. The Eastern
                  Shore is in the Coastal Plain region. In order to prevent the entry of pollutants into the ground
                  water in any aquifer, a soil zone or alternate protective measure or device is established to preserve
                  and protect the ground water.

                  State Board of Health - Waterworks Reeulations'

                  These regulations establish that the State Board of Health has the duty to ensure that all water
                  supplies destined for human consumption be pure water. All wells must be constructed by registered
                  Virginia contractors, and wells sampling done by approved laboratories.

                  Frequent sanitary surveys must be made by the owner to locate and identify health hazards. Once a
                  hazard is identified, the rate it is removed will be determined by the Division of Water Supply
                  Engineering. Sampling frequencies are listed in this regulation, and are based upon the number of
                  people served and whether or not the water supply is community, non-transient community, or non-
                  community. Categories for those to be sampled are coliform bacteria, inorganics, organics
                  (pesticides, VOC's, UC's, THM's), radiological, and physical characteristics like turbidity.
                  Nitrates must be sampled once every three years for community and non-transient community, and
                  every five years for a non-community water works.

                  When a new water supply system is considered, the capacity of the source must be adequate to
                  sustain anticipated growth. Construction and location requirements for drilled wells are the
                  following:

                      1) There shall be a distance of at least 50 ft. from the well to the property lines of the well lot.
                     2) If an access road is needed, it will be counted as part of the well lot.
                     3) There must be a horizontal distance of 50 ft. from the well to any septic tank, barn yard,
                         privy, pipe carrying sewage, petroleum or chemical storage tank, or pipe line. If plastic well
                        casing is used, the distance is 100 ft.

                  A water well completion report must be submitted. The report will include yield and drawdown
                  test data for a n-dnimum period of 48 hours.

                  Chapter 14.1 - ViMinia Pesticide Control Act. 1989 Session

                  This Act establishes a Pesticide Control Board which adopts rules concerning pesticides and the
                  application of them. The Board also serves the public by informing them as to the desirability and
                  availability of non-chen-tical and less toxic alternatives to chemical pesticides. It promotes the use
                  of Integrated Pest Management techniques and the safe and proper use of pest control products. The
                  Board has the power to restrict or prohibit the use of any particular pesticide. All pesticides must
                  be registered, and all applicators must have a license to do so (researchers excluded). The Board
                  acts as enforcer of rules, and can levee fines as a result of violations. Pesticide accidents must be
                  reported.








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                   YR 115-04-03 - Vkginia DeRartment of A&dculture and Consumer Services Rules and Regulations
                   for Enforcement of the Vireinia Pe ticide Law

                   These regulations list guidelines for the application, storage, disposal, and sale of pesticides. The
                   concept of "pest" is defined, and the types of pest control are placed into categories. Rules are
                   established for toxicity codes and for labeling pesticides.

                   VR 115-04-21 - Public ParticiRation Guidelines, Pesticide Control Board
                   Del2artment of Agriculture and Consumer Services. Pesticide Control Board
                   These guidelines establish methods for identification and notification of those persons or groups
                   interested in the development of regulations of the Pesticide Control Board. Mailing lists, public
                   meetings, committees, and the process of making a regulation are all described here.
                   VR 115-04-22 - ViMinia DeRarbnent of Agriculture and Consumer Services Regglations, Governing
                   Licensing of Pesticide Business ORerating Under Authority of ViMinia Pesticide Control Act
                   SeRtem
                   These regulations introduce procedures and requirements for obtaining a pesticide business license.
                   A license is required for anyone who sells, stores, mixes, applies or recommends pesticides, and this
                   includes pest management consultants. Businesses must demonstrate evidence of financial
                   responsibility and keep records according to the rules. Failure to be properly licensed, financially
                   responsible, or to submit records when asked can result in revocation, suspension, or denial of a
                   business license by the Board.

                   VR 115-04-23 - Regulations Governing Pesticide ARRlicator Certification Under Authorily o
                   Vir&ia Pesticide Control Act (Pro2osed. as of 2/91)
                   Several sections of VR 115-04-03 are superseded by these proposed regulations. VR 115-04-23 sets
                   standards of certification for persons specified by the statute to require certification, and standards
                   of financial responsibility for commercial applicators. Those who must meet the requirements are
                   individuals, employees, or representatives of government agencies who use or supervise the use of
                   pesticides in the performance of their official duties. All must pass a general exan-driation, and
                   then be tested in a specific category of pesticide application. The general tests assure that all
                   applicators are able to handle accidents, know labels, application techniques, laws and
                   regulations, can identify pests, and are aware of environmental affects of pesticides. Commercial
                   applicators not for hire are required to keep records for two years, while commercial applicators
                   must maintain records of each restricted-use pesticide.
















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                EASTERN SHORE OF VIRGINIA GROUND WATER STUDY COMMITTEE
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                      EASTERN SHORE OF VIRGINIA GROUND WATER STUDY COMMITTEE

                     Membership:

                     The Committee consists of the following representatives from Accomack and Northampton
                     Counties:
                             2 members from each Board of Supervisors
                             1 citizen appointee from each Board of Supervisors
                             the County Administrator from each county
                             the Executive Director of the Accomack-Northampton Planning District
                                Commission


                     Members:

                     Honorable C.D. Fleming, Jr.                              H. Mapp Walker
                     Accomack County                                          Citizen Member, Northampton County
                     P.O. Box 101                                             Bayford Road
                     New Church, VA    23415                                  Franktown, VA 23354
                     (804) 824-3724                                           (804) 442-2665

                     Honorable Donald L. Hart, Jr                             Arthur K. Fisher
                     Accomack County                                          Accomack County Administrator
                     P.O. Box 100                                             P.O. Box 388
                     Keller, VA 23401                                         Accomac, VA 23301
                     (804) 442-6818 (w); (804) 787-7166 (h)                   (804) 787-5700

                     Honorable P.C. Kellam, Jr.                               John M. Richardson
                     Northampton County                                       Northampton County Adn-dnistrator
                     RFD                                                      P.O. Box 66
                     Exmore, VA 23350                                         Eastville, VA 23347
                     (804) 678-5659 (w); (804) 442-7852                       (804) 678-5148

                     Honorable Parkes A. Downing                              Paul F. Berge, AICP
                     Northampton County                                       Executive Director, A-N PDC
                     Franktown, VA 23354                                      P.O. Box 417
                     (804) 442-6810                                           Accomac, VA 23301
                     J. Holland Scott                                         (804) 787-2936
                     Citizen Member, Accomack County
                     One Merry Lane
                     Onancock, VA n417
                     (804) 787-4382










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                   Technical Assistance:

                   Mr. Gary Anderson, Chief                                Ms. Virginia Newton
                   U.S. Geological Survey                                  Virginia State Water Control Board
                   3600 W. Broad Street, Room 606                          287 Pembroke Office Park
                   Richmond, VA 23230                                      Suite 310, Pembroke No. 2
                                                                           Virginia Beach, VA 23462
                   Mr. Jim Belote
                   Extension Agent, Agriculture                            Mr. Gary Oliveri
                   County of Accomack                                      Accomack County Planner
                   P.O. Box 60                                             P.O. Box 388
                   Accomack, VA 23301                                      Accornack, VA 23301

                   Mr. Mark Bushing                                        Ms. Donna Richardson
                   Virginia State Water Control Board                      U.S. Geological Survey
                   287 Pembroke Office Park                                3600 W. Broad Street, Room 606
                   Suite 310, Pembroke No. 2                               Richmond, VA 23230

                   Mr. Mike Focazio                                        Mr. John Selby
                   U.S. Geological Survey                                  USDA, Resource Conservation
                   3600 W. Broad Street, Room 606                          & Development
                   Richmond, VA 23230                                      P.O. Box 127
                                                                           Accomack, VA 23301

                   Ms. Pixie Hamilton                                      Mr. Gary Spieran
                   U.S. Geological Survey                                  U.S. Geological Survey
                   3600 W. Broad Street, Room 606                          3600 W. Broad Street, Room 606
                   Richmond, VA 23230                                      Richmond, VA 23230

                   Mr. John L. Humphrey                                    Mr. Terry Wagner
                   Planning and Zoning                                     Virginia State Water Control Board
                   Northampton County Adn-dnistration                      2111 N. Hamilton Street
                   P.O. Box 66                                             Richmond, VA 23230

                   Mr. Robert F. Jackson                                   Mr. J. Rodney Lewis
                   Virginia State Water Control Board                      District Conservationist
                   287 Pembroke Office Park                                Soil Conservation Service
                   Suite 310, Pembroke No. 2                               Accomac, VA 23301
                   Virginia Beach, VA 23462













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                                                                                                                   Table E-I: Water Balance for the Eastern Shore of Virginia

                               Recharge to the Columbia (Unconfined) Aquifer
                               (After Dunne and Leopold, 1978)



                                                                                Potential ET
                                                Average          Average               (from     Precipitation Accumulated                       Change                      Soil        Soil    Available        Assume
                -74                             Monthly          Monthly       Thornthwaite           minus          Potential         Soil       in soil     Actual Moisture Moisture for runoff or                50%      Detention Detention
                1z                           Precipitation Precipitation          method)         Potential ET      Water Loss Moisture         moisture          Er      Deficit Surplus          recharge        Runoff    (recharge) (recharge)
                                                (inches)            (mm)               (mm)           (mm)             (mm)            (m m)      (mm)            (mm)       (mm)       (mm)          (mm)          (mm)         (mm)       (inches)

                                   January         3.41             86.6               6                81                             200           0            6           0           81           136           68            68           2.7

                                 February          331              84.1               8                76                             200           0            8           0           76           144           72            72           2.8

                                    March          4.13             104.9              24               81                             2DO           0            24          0           81           153           77            77           3.0


                                     April         2.92             74.2               46               28                             200           0            46          0           28           105           52            52           2.1

                                      May          3.47             88.1               77               11                             200           0            77          0           11           63            32            32           1.2

                                       June        3.51             89.2               103.5            -14              -14           190           -10          99.2       4.4          0            32            16            16           0.6

                                       July        4.10             104.1              118.7            -15              -29           185           -5           109.1      9.6          0            16            8             8            0.3

                                    August         4.28             108.7              111              -2               -31           183           -2           110.7      03           0            8             4             4            0.2

                               September           3.41             86.6               84               2                -29           185           2            84          0           0.2          0.2           0.1           0.1        0.005

                                   October         3.57             90.7               52               39                             200           15           52          0           39           39.1          20            20           0.8


                               November            2.96             75.2               25               50                             200           0            25          0           50           70            35            35           1.4


                                 December          3.37             85.6               10               75                             200           0            10          0           75           110           55            55           2.2


                                   TOTAL           42.44            1078               665              413                            2343                       651        143          442          976           438           438





                                                               Note. Assumes soils with 200 mm (8 inches) of available water capacity





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                                                     Table E-2: Thorthwaite Method for Evapotranspiration (ET) Calculation
      3


                     LOCATION:                                         Eastern Shore, Virginia
                     CLIMATOLOGICAL DATA FROM:                         Painter, Virginia
                      YEARS OF RECORD:                                      6         (1985-1990)



                                           Mean
                                        Monthly       Positive Air                     Uncorrected                                         Potential      Potential
                                           Air        Temperature        Monthly            EIr        Latitude Correction Factor              EIr             EIr
                                     Temperature          Values       Heat Index (cm/month)             Latitude            400 N       (cm/month) (in/month)
                           January         3.94             3.94            0.70            0.76               January         0.80            0.61            0.24
                         February          4.28             4.28            0.79            0.85              February         0.89            0.76            0.30
                            March          9.11             9.11            2.46            2.40                 March         0.99            2.38            0.94
      OQ
                             April         13.72            13.72           4.55            4.21                  April        1.10            4.63            1.82
                               May         18.67            18.67           7.21            6.41                   May         1.20            7.69            3.03
                               June        22.50            22.50           9.55            8.28                    June       1.25            10.35           4.08
                               July        25.17            25.17-          11.29           9.65                    July       1.23            11.87           4.68
                            August         25.17            25.17           11.29           9.65                August         1.15            11.10           4.37
                        September          22.17            22.17           9.33            8.11            September          1.04            8.44            3.32
                           October         16.83            16.83           6.18            5.56                October        0.93            5.18            2.04
                        November           10.72            10.72           3.14            3.00             November          0.83            2.49            0.98
                         December          5.89             5.89            1.28            1.32             December          0.78            1.03            0.41


                                                   ANNUAL HEAT INDEX, I =                   67.77
                                                                       "a" factor =         1.37



                                                                                                                 Total Potential ET            67              26
                                                                                                                                            cm/year         in/year





                                                                                                 E-2










                              Table E-3: Water Balance for the Eastern Shore of Virginia
                                     Recharge to the Yorktown-Eastover Aquifer

                                                                 Derived Equation:
                  Recharge Rate Calculations:                    Recharge (R) = [ 8 T h) - [LA2 - 4 XA2]

                                                                 Transmissivity M in ft2/day
                                                                 Head N in feet (at ground water divide)
                                                                 x = 0 in all cases (at ground water divide)
                                                                 Width of peninsula Q in feet


                  Recharge values (below) in feet per year

                          For peninsula width of           4     miles
                                              T =          T        T =        T           T            T
                                              500          1000     2000       3000        4000         5000
                          h =      15         0.05         0.10     0.20       0.29        0.39         0.49
                          h =      18         0.06         0.12     0.24       0.35        0.47         0.59
                          h =      20         0.07         0.13     0.26       0.39        0.52         0.65
                          h =      22         0.07         0.14     0.29       0.43        0.58         0.72
                          h =      24         0.08         0.16     0.31       0.47        0.63         0.79
                          h =      26         0.09         0.17     0.34       0.51        0.68         0.85
                             Average   R      0.07         0.14     0.27       0.41        0.55         0.68-
                  Overall Average R =1        0.29    feet per year

                          For peninsula width of           6     miles
                                              T =          T        T =        T           T            T
                                              Soo          1000     2000       3000        4000         5000
                          h =      15         0.02         0.04     0.09       0.13        0.17         0.22
                          h =      IS         0.03         0.05     0.10       0.16        0.21         0.26
                          h =      20         0.03         0.06     0.12       0.17        0.23         0.29
                          h =      22         0.03         0.06     0.13       0.19        0.26         0.32
                          h =      24         0.03         0.07     0.14       0.21        0.28         0.35
                          h =      26         0.04         0.08     0.15       0.23        0.30         0.38
                             Average   R      0.03         0.06     0.12       0.18        0.24         0.30
                  Overall Average R =         0.13    feet per year
                                          ff@oi

                          For peninsula width of           8     miles
                                              T =          T        T =        T           T            T
                                              500          1000     2000       3000        4000         5000
                          h =      15         0.01         0.02     0.05       0.07        0.10         0.12
                          h =      18         0.01         0.03     0.06       0.09        0.12         0.15
                          h =      20         0.02         0.03     0.07       0.10        0.13         0.16
                          h =      22         0.02         0.04     0.07       0.11        0.14         0.18
                          h =      24         0.02         0.04     0.08       0.12        0.16         0.20
                          h =      26         0.02         0.04     0.09       0.13        0.17         0.21
                             .111verageR      0.02         0.03     0.07       0.10        0.14         0.17-
                  Overall Average R =1        0.07    feet per year



                     Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                        E-3








                      Table E-4: Recharge Calculations for the Yorktown-Eastover Aquifer


                      Volumetric Recharge Calculations
                      (All figures in million gallons per day)
                                                                  Area for Area for Area for Area for Area for
                                                  Recharge       Recharge Recharge Recharge Recharge Recharge
                                                        Rate        (mi2)          (mi2)        (mi2)           (mi2)  (mi2)
                                                 (feetlyear)          100          L50          200             300    400
                                                        0.05          3            4            6               9        11
                                                        0.10          6            9            11              17       23
                                                        0.20          11           17           23              34       46
                                                        0.30          17           26           34              51       69
                                                        0.40          23           34           46              69       91
                                                        0.50          29           43           57              86       114
                                                        0.60          34           51           69              103      137   1




                      Comparison of Water Usage on the Eastern Shore with Recharge Volumes
                      Area of confining layer receiving recharge = 200 square miles
                      Variable recharge rates
                      (All figures in million gallons per day)

                                                        Year          Year         Year         Year            Year   Year     Permitted
                                                        IM            1986         1987         1988            1989   1990        Amount
                               Public Sources:          1.243         1.264        1.259        1.241           1.415  1.114         4.462
                          Industrial Sources:           3.412         3.052        3.157        3.064           3.433  3.430        11.143
                        Total Withdrawals:              4.655         4.316        4.417        4.306           4.948  4.544        15.604

                             Recharge
                                  at 0.05 ft/yr         6             6            6            6               6        6            6
                            Excess  or Deficit.         1.1           1.4          1.3          1.4             0.9      1.2          -9.9
                                  at 0.10 ft/yr         11            11           11           11              11       11           11
                            Excess  or Deficit:         6.8           7.1          7.0          7.1             6.6      6.9          -4.2
                                  at 0.20 ft/yr         23            23           23           23              23       23           23
                            Excess  or Deficit:         18.2          18.5         18.4         18.5            18.0     18.3         7.2
                                  at 0.30 ftlyr         34            34           34           34              34       34           34
                            Excess  or Deficit:         29.6          30.0         29.9         30.0            29.4     29.7         18.7
                                  at 0.40 ftlyr         46            46           46           46              46       46           46
                            Excess  or Deficit:         41.1          41.4         41.3         41.4            40.9     41.2         30.1
                                  at 0.50 ftlyr         57            57           57           57              57       57           57
                            Excess  or Deficit:         52.5          52.8         52.7         52.8            52.3     52.6         41.5
                                  at 0.60 ft/yr         69            69           69           69              69       69           69
                            Excess  or Deficit:         63.9          64.2         64.1         64.3            63.7     64.0         53.0




                          Ground WateT Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                                 E-4






                                    Recharge to the Yorktown-Eastover (Confined) Aquifer
                                      DERIVATION OF THE RECHARGE EQUATION






                                   WEST              ICentraJ Plateau I            EAST
                                 Chesapeake         PRECIPITATION                  Atlantic
                                     Be,                                           Ocean

                                                                       Water Table
                                                                             Plezornetric Level







                                      jxx
                                         w. . ............






                                                             ...........

                                       S  I
                                                                                Salt
                                                                               Ground
                                       Water                                    Water


                                                             L
                                   El 4sh Water Aquffer
                                                           zoo
                                   El Fresh Water Aquitard x=U2

                The governing differential equation for steady state flow in one dimension      is:
                                                          d 2h/dX2  = -w/T. (1)
                where
                h = the hydraulic head of the Yorktown-Eastover aquifer,
                x = the lateral distance from the center spine of the peninsula (always positive),
                w    the recharge rate of the Yorktown-Eastover aquifer,
                T    the transmissivity of the Yorktown-Eastover aquifer, and
                L    width of the peninsula.
                Integrating once, the equation becomes
                                                       dh/dx = (-w/T)x + C1. (2)
                At the ground water divide, x = 0 and dh/dx = 0. Substituting these values into equation (2) results
                in the following equation, upon which the constant C, can be solved for:
                                                             0 = -w/T(O) + C 1
                                                                   C, = 0.
                Integrating again, the equation becomes
                                                      h = (-w/2T)x2+ C  1x + C2.  (3)




                    Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                 E-5




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                                  BUILDOUT NITROGEN LOADING CALCULATIONS
                                                                 APPENDIX F    I
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                                                                                         Table F-1: WPA (A) Future Nitrogen Loading Calculations



                                           NITROGEN LA)ADING CALCULATIONS
                                           WPA A Future (spine only, all soils)

                                           INPUT FACTORS
                                           Number of Residential units                                                   379


                                           Sewage flow per house (galiday)                                               163

                                           Commercial/Industrial land (Scres)                                            60

                                           ComAnd. sewage flow per scre                                                  423

                                           N-conc. in sewage effluent (mg/1)                                             40

                                           lawn am per house (square fed)                                                slow

                                           Pavement per house (square fed)                                               3W

                                           Road arm (square fee)                                                 IA5Io040

                                           Roof area per house (square fed)                                              Lsw

                                           Agricultund area (acres)                                                      U59

                                           Landfills (acms)                                                              0


                                           Septage lagoons (gallonstyr)                                                  0

                                           Septege N concentration (mg1l)                                                43

                                           Animal burial (Ibs /yr)                                                 222,081

                                           Total recharge area (acres)                                                   3,417

                                           Reduage rate for pervious                                                     17
                                           area fin/yr)

                                           Recharge rate for impervious                                                  34
                                           area (in/yr)

                                                           INPUT                                             CALCULATIONS                                            RESULTS


                                                    Sewage (galiday)                                                                              CALCULATED LA)ADING (LBSNR)
                                                           120,915                     x N-conc (mg/1) x 3.785 1/gal x 365 days/yr: 4M000 rng/lb                         14,715

                                                     Lzwn area (sq ft)
                                                           U9510W                                           x O.OOD9 lb Nlsq It                                          2,606

                                                  Pavement area (sq ft)
                                                           1,7",340                                        x O.OOMI lb N/sq ft                                           549

                                                     Roof area (ag ft)
                                                           868,5W                                          x 0.00015 lb N/sq ft                                          130

                                                   Natural area (acres)
                                                             871                                 x 43560 aq ft/acre x 0.000005 lb Nlaq ft                                190

                                                      OkherSource3
                                                   Agriculture (acres)
                                                           2,3"                                  x 89 lbs N/acre/yr x 25% leaching rate                                  32,492

                                                     L.andfills (acres)
                                                              0                                           1184 lbsN/acre/year                                            0

                                               Septage I.Agoons (X&Vyear)
                                                              0                                x N-conc (rng/1) x 3.795 1/gal: 454000 rng/lb                             0

                                                Animal brurial (lbs/yew)
                                                           222,081                                       x 33 % N concentration                                          7,329

                                                                                                          TOTAL NITROGEN LDADING (LBS/YR)                                78AM
                                                                                                                                                         TOTAL RECHARGE (MGrYR)
                                           techaige from sew/*!Ptage (gal/day
                                                           120,91,                              x 365 days/yr: 1,000,000 gal/million gal                 -- 44

                                               Total pervious ares (sq ft)
                                                        140",680                    x 17 in/yr /12 in/ft x 7AS gal/cu ft: 1,000,000gal/million gal                       1,335

                                              Total impervious am& (ag ft)
                                                           3,945,340                x 34 in/yr /12 in/ft x 7.48 gal/cu ft: I,000,000gal/million gal

                                                                                                                         TOTAL RECHARGE (MGALJYR)
                                           7OTAL NITROGEN LOAD/TOTAL RECHARGE X &IA000 MG/LB: 3,795,000 L/MGAL
                                                                                  I =RECHARGE NfTROGEN CONCENTRATION (W orppm)

                                           PREPARED UY HORSLEY WITTEN HEGEMANNo INC.



                                                                                                                         F-I







                                                                                       Table FL2. WPA (A) Future Nitrogen Loading Calculations - Developable Soils Only



                                               NITROGEN LOADING CALCULATIONS
                                               WPA A Future (spim: only, Arapahoe sails; considered undevelopable)

                                               INPUT FACTORS
                                               Number of Residential units                                                    27

                                               Sewage flow per house (plldwf) 1                                               165

                                               Cimurwdalifindustrial land (mcrm) 1                                            60

                                               ComAnd. sevoge Dow per acre             1                                      423
                                               (Sal/day)
                                               N-amc.insewag effluent(W611)                                                   40

                                               Lawn area per house (squane fast)                                              5,000

                                               Pavement per house (square feell                                               SDO

                                               Road area (square feet)                                                        2AB1,040

                                               Roof am Pat house (square feed          I                                      1AW

                                               Agricultunal area (acres)                                                      2,819

                                               Landfills (acres)                                                              0
                                               Septage lagoons (gallonad"                                                     a             77=
                                               Septage N concentration (nM                                                    45            --7=

                                               Animal burial (lbs tyr)                                                        222,081

                                               Total recharge area (scres)                                                    3,417

                                               PAVhWze rate for Pervious               1                                      17
                                               am& finlyr)

                                               Recharp oft far iznp@                                                          34
                                               am (intyr)

                                                               INPUT                                             CALCULA77ONS                                            RESULTS

                                                         Sewage (gal/day)                                                                             CALCULATED LOADING (LBS/YR)
                                                               29,835                      x N-cmC(mA/l) x 178511a x 365 days/yr: 45M mA/lb                                      3,632

                                                         Lawn area (ag ft)
                                                               IM,000                                            xD.MlbN/sqft                                                    U2

                                                       Pavement ma (sq ft)
                                                              1,494,50                                          x O.ODD42 lb N/sq ft

                                                          Roof ar" (sq it)
                                                               K500                                             x Q00015 lb N/sq ft                                              6

                                                        Natural am (acres)
                                                                 499                                  x 43560K ft/aue x 0.000005 lb?,J/sq it                                     109

                                                           Other Sources
                                                         Agricultutv (scres)
                                                                3@819                                     x 89 lbs N/acre/yr *M S leach                                          62.733

                                                          Landfills (acres)
                                                                   0                                           1184 lbaN/acre/year                                               0

                                                    Septalte Lagoons (gavvem
                                                                   0                               x N-cmc (mg/1) x 3.785 1 kal: 45M MR/lb                                       0

                                                     Animal burial UWyear)
                                                               222,081                                        x 3.3 % N concentration                                            7,329

                                                                                                               TOTAL NITROGEN LOADING (LBS)YR)                                   7OS7

                                                                                                                                                              TOTAL RECHARGE (MGIM
                                               techarge fion, sew/septaxe (Ral/day
                                                               29,835                                x 365 days/yr: 1,000,0DO gal/million gal                                    11
                                                     Total pervious ants, (sq ft)                                                     ODD W/rndbcn A&I                           1,%7
                                                             146,002,660                  X171n/yr/12in/ x7.48gal/cuft:l

                                                    Total impervious area, (Ig ft)
                                                                                          x 34 in tr /12 in/ft x 7.48 gal 1cu ft: 1,0m,= gal/million gal                         60

                                                                                                                              TOTAL RECHARGE (MGALJYR)                           1,618
                                               !UFAL -NrrRocEN LOAD                             GE X 454,0DI) MG/ 1.11: 3,755,UUU LIMUAL                                         -
                                                                           . 22Z@@@ARGE NITROGEN CONCENTRATION (we or PPIT01                                                     5.5

                                               PREPARED BY HORSLEY WITTEN HECEMANN, INC.










                                                                                                                                    F-2







                                                                                                      Table F-3k WPA (B) Future Nitrogen Loading CAlculatiMs



                                              NITROGEN LOADING CALCULATIONS
                                              WPA 0 Future (spine only, all sails)

                                              INFUTFACTORS
                                              N wil- of Residential units                                                  IXM         ---- 777=
                                              Sewap flow per house (sal/clay) 1                                            165                 7777=

                                              Cunercialndustrial land (acrea)                                              692

                                              C=L/Ind. sewage (lam per me                                                  423                 7777=
                                              (Sal/day)
                                              Noconc, in sewage effluent (ngd)                                             40

                                              Lwvmaveaperl              (square feet)                                      51000

                                              Paremen perhoupe(equarefeitt)                                                SDO

                                              Road area (square feet)                                                  2.IX440

                                              Pod am per house (square feed                                                LAM

                                              Agricultural areat (acres)                                                   2,3314

                                              Landfills (acres)                                                            Lo

                                              Septale lagoons (gallonstyr)                                              430,WO

                                              S.pug. N concentration (m&M               1                                  43

                                              Animal burial (lbo lyr)                                                   319,449

                                              Total recharge area (acres)                                                  4,915

                                              Recharge rate for pervious                                                   17
                                              area (in/yr)

                                              Recharge rate for invevious                                                  34
                                              area fintyr)

                                                               INPUT                                              CALCULATIONS                                              RESULTS

                                                         Sew.g. (S@l/d.y)                                                                                CALCULATED LOADING (LBSrAU
                                                               496,656                      x N-conc(mg/l) x 3.7851/a x 365 days/yr: 45M mA/lb                                  60,4S3

                                                         L@ am (sq ft)
                                                              6,180,0w                                            x OjM lb Wag ft

                                                         avement area (sq fo
                                                              2.7S2.440                                          . CLOOD42 lb N /,q ft                                          1.156

                                                         Roof area (sq ft)
                                                              I.&%1000                                           x 0.0001S lb N/sA ft                                           278

                                                         Natural area (acres)
                                                                1,492                                  x 43560 sq ft/acre x 11000005 lb N/sq ft                                 325

                                                          Other Soumes
                                                         Apgriculture (acres)
                                                                2,334                                      x 89 lbs N/acre/yr * 25 S leach                                      SL934

                                                         Landfills (so")
                                                                 ISO                                            1134 lbsN/acre/year                                             177,IM

                                                   SeptaSt Lagoons (gat/year)
                                                               450,000                              x N-conc (mg/O x 3.7851/0:45M mg/lb                                         244

                                                    Animal burial (lbs/y-)
                                                               319,449                                         x 3.3 % N concentration                                          101S42

                                                                                                                 TOTAL NITROGEN LOADING (LBSfYR)                                307,620

                                                                                                                                                                 TOTAL RECHARGE(MG/YR1
                                              techarge from sew/wptage (gal/clay)
                                                               4%,656                                x 365 da)%/yr: 1,000,ODO gallmillion a                                     292

                                                    Total peMous arza leg ft)
                                                             187,"2,624                   x 17 in/yr /12 in/ft x 7.48 ital/m ft: LOMAOD

                                                  Total unpMcaz area (sq ft)
                                                             26,194,776                   x 34 in/yr /12 in/ft x 7.48 gal /cu ft: 1,0M,W0 gal/million gal                       555

                                                                                        i                                  TOTAL RECHARCE(MGALIM!                               2,728
                                              TOTAL NITROGEN LDAD/TOTAL RECHARGE X 454,000 MG/LB:3795,000 L/MGAL
                                                                                        r --RE(3iARCE NITROGEN CONCENTRATION logo orppadl                                       13.5         71

                                              PREPARED BY HORSLEY WITTEN HECEMANN, INC.










                                                                                                                                    F-3






                                                                                         Table FL4: WPA (B) Future Ni"ert Loading Calculations - Developable Solls Only



                                                 NITROGEN LOADING CALCULATIONS
                                                 WPA 5 Fubim (spine only, Arapahoe scils, considered undevelopable)

                                                 INPUT FACTIORS
                                                 NM,ba of RdddW units                                                       1.211

                                                 Sewage Rorie per boast (gal/day)                                           165
                                                 ConumercialrInduontal land (acres) 1                                       622               --77=

                                                 ComAnd. sewage Russ, per am             1                                  423
                                                 (gal/day)
                                                 N-conc. in sewage effluent WS11)        1                                  40                77=

                                                 Lawn am parl             (MIumefew      I                                  SAM-

                                                 Pavement per house (square: feet)                                          Soo

                                                 Road am (minare fect)                                                      2,12MAW

                                                 Roof arem per house, (square 11NO       I                                  IAM

                                                 Agricultural am facres)                                                    2.3SS
                                                 Landfills (acres)                                                          IM                77==
                                                 Septage lagoons (gallons/yr)                                               450,M0            --      -771

                                                 Septage N comcamtradon (n*4)                                               45
                                                 Aninial burial (lbs lyr)                                                   319,449           777=
                                                 ToW recharge am (acres)                                                    4,915             77=

                                                 Redurge rate for perviorms                                                 27
                                                 am (ir-jyr)

                                                 Recharge rate far imopervious                                              34
                                                 me (intyr)

                                                                 INPUT                                            CALCULATIONS                                              RESULTS

                                                          Sewage (X&Vday)                                                                                CALCULATED LOADING (LBSIM
                                                                 4W31                        x N-conc (mg/1) x 3.7951/gW x 365 days/yr: 45M mgAb                                59,951

                                                           Lmn area (og ft)
                                                                 6,055,000                                        x O.OW9 lb N /sq ft                                           S,00

                                                        Pavexnent me (mg it)
                                                                 2,739,940                                        x 110OD42 lb N/aq ft                                          1,151

                                                           Roof am (ag ft)
                                                                 11816,SOD                                         x0.0DDISJbN/sqft--                                           272

                                                         Natural area 4acres)
                                                                 1,474                                  X43%Osqft/acrex 0.000DOMN/sqft                                          3.21

                                                                 Other Sources
                                                          Agriculture (acres)
                                                                 V55                                       x 89 lbs N/scre/yr * 25 % leach                                      32,407

                                                           LandfWs (acres)
                                                                  L5 a                                           1184 lbsN/acre/year

                                                     Septage Lagoomms, (gally,")
                                                                 450,000                             x N-conc(mg/l) x 3.7851/gal: 450M mg/lb                                    2"

                                                      Animal burial (lbs1year)
                                                                 319,449                                        x 3.3 % N concentration                                         10sa

                                                                                                                 TOTALNITR CENIDADINC(LBSrYR)                                   307,463
                                                 tarchame hm sewlseptaite fitaIV/da                                                                              TOTAL RECHARGE (MG/M
                                                                 492,M                                x 365 dayg/yr: 1,000,ro RAI /mflhm gal                                    ISO

                                                      Total pervious we's (ag ft)
                                                                 187,952,624               x 17 in/vt /12 in/ft x 7.48 gal /cu ft: 1,000,000                                    1,"2

                                                    Tvial unpamous am (sq ft)
                                                                 26,144,776                x 34 in/T-/12 -m1ft . 7.48 gal /cu ft: IAM,000 PI /        on gal                    S54

                                                                                                                            TOTAL RECHARGE (MCAL/M                              2,72
                                                 TOTAL NITROGEN LOAD/TO`rAL RECHARGE X 454,000 MG/LS: V85,000 L/MCAL
                                                                                         I -REC3iARCENITROCENCONCEhrrRATION(nwAorppnOi                                          13S

                                                 PREPARED BY HORSLEY WITTEN HECEMANN, INC.
                                                                                                                                                           da407



                                                                                                                                      F-4







                                                                                                    Table F-&WPA (C) Future N*trogm Lzading Calculations


                                              NITROGEN LOADING CALCULATIONS
                                              WPA C Future (opine only, all and*)

                                              INPUTFACTORS
                                              Number of Reeldential units                                                      10,137

                                              Sewage flowperhouse(gal/day)                                                     Ms            777=

                                              Comme7cialfIndustrial land (acres)                                               110"

                                              ComJInd. wwap flow per am                                                        423
                                              (Sal/day)
                                              N-cont. in sawage effluent (mg1l)                                                40

                                              Lawn area per house (square feW                                                  5,0M

                                              Pavemartf, per I         (equare two                                             SM

                                              Road ares (square feet)                                                          41123812W

                                              Rod am per house (square feet)                                                   1AM

                                              Agricultural area (acrea)                                                        2A29

                                              Landfills (acres)                                                                a

                                              S"Se lagoons, (gallonslyr)                                                       0

                                              Sepuge N concentration (n*A)                                                     45

                                              Animal burial (lbs tyr)                                                          618,M4

                                              Total mduwgt area (acres)                                                        9AM

                                              Redutrge rate for pervious                                                       27
                                              area (intyr)

                                              Reduarp rate for impervious                                                      34
                                              am& finlyr)

                                                              INPUT                                              CALCULATIONS                                             RESULTS

                                                       Sewage (gallday)                                                                                CALCULATED LOADING (LBS/YR)
                                                             2,U5,977                      x N-conc(mg/l) x 3.7851/0 x 365 days/yr: 454000 mgAb                                259,"4

                                                        L.awn am (eq ff)
                                                             S0,733tooo                                         x 0.0009 lb Nlag ft                                            45,707

                                                      pave-iont area (ag ft)
                                                             9,216,700                                          x O.ODD42 lb N/sq ft                                           3,871

                                                        Roof arva (sq ft)
                                                             13,235,5M                                          x OLM015 lb N /eq ft                                           2,285

                                                      Natural area (acres)
                                                               4,089                                 x 43560 sq ft /acre x MOOM lb N /sq ft                                    991

                                                          Other Sources
                                                       Aoculture (acres)
                                                               3@629                                       x 89 lbs N/acre * 25 Meach                                          56,496

                                                        Landfills (acres)
                                                                 0                                            1164 lbs N/acre/year                                             0

                                                  Septage Lazoorts fitallyear)
                                                                 0                                 x N-conc(mg/b x &7951/gal: 45=mg/lb                                         0

                                                    Animal burial flbs/year)
                                                              618,024                                        x 3.3 % N conceritrartion                                         20,39S

                                                                                                               TOTAL NITROGEN LOADING (LBS/YR)                                 3M,419
                                              techarx fmm sawfeeptage (gal/da                                                                            ---  TOTALRECHARCE(MGfM
                                                             xU5,9"                                 x MS days/yr: 1,00DODD A&I tmilbon gal                                     776

                                                   Total peMous am log ft)
                                                            366,%S,920                  x 17 m/yr /12 m/ft x 7.48 Ael /M ft: 1,000,0DO ghl/ndllion gal                         3ASS

                                                 Total impervious area (ag ft)
                                                             47A26,220                  x 34 in/yr /12 in/ft x 7.48 gallcu ft: 1,ODD,000 W/-.Mlb-Sl                            1.009

                                                                                                                               TOTAL RECHARGE (MCAUYR)l                        4670
                                              ITUTAL NITROGEN LOAD/7%)TAL RECHARGE X 451,0M MG/LB: 3,795,00D L/MGAL
                                                                                     r --REGiARGE NITROGEN CONCENTRATION (mew ppm)j                                            1-3

                                              PREPARED BY HORSLEY WITTEN HEGEMANN, INC










                                                                                                                                  F-5







                                                                                                     TaWe F-4k WPAM Future Nitrogen Loading Calculation*



                                               MTROGEN LOADING CALCULATIONS
                                               WA D Putm (spine only, all wils)

                                               INPUT FACTORS
                                               Number of Residential units                                                =96

                                               Sewage flow per house (gaivday)         1                                  265
                                               Cammummciallindustrial twd (acrem) 1                                       325               777=

                                               CamAnd. sewage flow par acre                                               423
                                               (Sal/day)
                                               N-anw.insew efftment(wo)                                                   40
                                               Lown am per house (square feed                                             5,000             7-==

                                               ptseusent P. house (.F. faso                                               500

                                               Road am (scItuat feet)                                                 4,530,240

                                               Red am per house (square, I"                                               IAW
                                               Agdcultural am& (acres)                                                    IA73       --7=7=

                                               Landfills; (acres)                                                         0

                                               Sertase as- (gallons"                                                      0

                                               Sepiage N concentration (=%4)                                              45

                                               Aninw bmial ubm lyr)                                                       6-M-0-m
                                               Total recharge arta (acres)                                                106431            777=

                                               Recluarse rate for parvious                                                17
                                               am unlyr)
                                               Recluerge rate for iznporvious                                             34                777=
                                               area fir.),r)

                                                                INPUT                                             CALCULATIONS                                                 RESULTS

                                                         Sewage (Sal/day)                                                                              CALCULATED LOADING (LBSIM
                                                               ZM,915                       x N-cmc (mit1l) x S.7851 la x 365 days/yr: 456(= mptAb                             2",M

                                                          La" area lag ft)
                                                              61,460,WO                                          x 0.0009 lb N/aq ft                                           S51m
                                                       Pavemmt area (ag ft)                                                                                                    4,455
                                                              10,679,240                                        x a0W42 ]b N/sq ft

                                                          Roof area tiq ft)
                                                              18,"4,0D0                                         x 0AW15 lb Wag ft                                              2,767

                                                        Natural area (screw
                                                                6,IS3                                 x 43560,q ft/.- . 0.0000M lb N /,q ft                                    I_U0

                                                           Other sources
                                                         Agriculture lacres)
                                                                L673                                        x 84 lbs N/acre x 25 % leach                                       35,1"

                                                          Landfills (acres)
                                                                   0                                           1184 lbsN/acre/year                                             0

                                                    Septage Lagoons (gallycar)
                                                                   0-                               xN-amc(MR/I)-3,'SSI/A&1:454OWmA/lb                                         0
                                                     Animnal burial (lbstrw)                                                                                                   22,372
                                                                677,9"                                        x 3.3 % N concentration

                                                                                                                TOTAL NITROGEN LOADING (LBStYR)                                M,407

                                                                                                                                                               TOTAL RECHARGE(mcfm
                                               tech . fivot me-Imptage gnal/da
                                                               I'm,915                               x 365 days/yr: IAW,000 0/million FAJ                                      822

                                                     Total pervious arva log ft)
                                                              413,817,620                 x 17 in/yr /12 in/ft x 7A$ sal/cu ft: 1,0W,000 salloWbon As]                         4,MS

                                                   Total impervious avem (ag ft)
                                                              40,556,740                  x 34 in/vr /12 in/ft x 7.48 Sallcu ft: 1AW,=                                         no
                                                                                                                          TOTAL RECHARGE(MGERZ4                                6,066
                                               TOTAL NITROGEN IDAD /TOTAL R ECHARGE X 454,000 MG/ LD: 3,73,,,mu L/ MGAL
                                                                                       T    RECHARGE N rrROCEN CONCENTRATION (vall or Ppu%)l                                   --7.3

                                               PREPARED BY HORSLEY WITTEN HEGEMANN, INC










                                                                                                                                     F-6








                                                                                                     TaWe F-7., WPA( E) Future Nitrogen Loading Calculations



                                              NITROGEN LOADING CALCULATIONS
                                              WPA E Future (spine only, all soils)

                                              INPUT FACTORS
                                              Number of Residential units                                                  L%409

                                              Sevem" fiovr per house (Sal/day)                                             165
                                              Cartursercial/Industrial land (acres) 1                                      239                 777=

                                              ComAnd. sewage flow per am                                                   423
                                              (Sal/day)
                                              N@c in sevrage effimmi (u%fi)                                                40                  777=

                                              Lawn am per house (square feW            1                                   5,000

                                              Pavement per home (square feed           I                                   Soo

                                              Road am (square feet)                                                   4,704o48D

                                              Roof am per house (square feel)                                              IAW

                                              Agricultural am (acres)                                                      M

                                              Landfills lacres)                                                            0

                                              Septage lagoorti, (gatlanslyr)                                               0

                                              Septage N concentration WV)                                                  45

                                              AWmal burial (lbs 1yr)                                                       0

                                              Total recharge am& (acres)                                                   10,7%

                                              Reduirge rate for pervious                                                   17
                                              area finlyr)
                                              Recharp rate for inqmr@vuz                                                   34                  7-77=
                                              area Unlyr)

                                                               INPUT                                             CALCULATIONS                                               RESULTS

                                                        Sewage (galfday@                                                                                 CALCULATED LOADING (LBS/YR)
                                                              2,313,582                     x N@c(mg/]) x.1785 lIpA x 365 days/yr: 454= mg/ib                                    281,610

                                                        Lawn area (sq it)
                                                             67,045,ODO                                           xO.0009lbN/sqft                                                -60,341

                                                      ravcvvmt area (59 it)
                                                             11,408,980                                          x CL00042 lb N /ag ft                                           4,792

                                                         Roof ama (sq ft)
                                                             20,113,500                                          x 0.00015 lb N /sq ft                                     _.%017

                                                      Natural am& (acresl
                                                               7,567                                   x43%0sgft/acmx0L00Wffi1bN/*gft

                                                          Other Sources
                                                        Aoculture (acres)
                                                                728                                         x 79 lbs Nlacre x 25 % leach                                         14,370

                                                         Landfills (acres)
                                                                   0                                            1164 IbBN/acre/year                                              0

                                                  SeptaRe LaXoons ggal/year)
                                                                   0                                x N-cDnc (mit/1) x 3.795 1 /gal: 4MM MA/lb                                   0

                                                    Animal burial (lbstywr)
                                                                                                               x 3.3 % N concentration                                           0

                                                                                                                 TOTAL NITROGEN LOADING (LBSfYR)                                 365,777

                                                                                                                                                    -TOTAL RECHARGE(MG/M
                                              techarge from newlseptalle (Ital/day
                                                              2,313@w                                x 365 days/yr: I,0W,0D0 stal/mMon gal                                       8"

                                                   Total perrious, ama (ag it)
                                                             433,54S,860                  x 17 in /yr /12 in/ft x 7.48 gal /cu ft: I,OM,000 Aal/ffdlhm A&I                       094

                                                  Total impervious ama (ag ft)
                                                             36,727,WD                    x 34 m/yr /12 in/ft x 7.48 Aal/cu ft: 100,000 0/millian gal                            778

                                                                                       i                                   TOTAL RECI    iARCE(MC                                6,217
                                              TOTAL NITROGEN LOAD/TDTAL RECHARGE X 4M,M0 MC/LB: 3,795,000 L/MCAL
                                                                                     T ---OiARGENrrROCENCONCEN"rRATION(nVAwppWI                                                  7.1

                                              PREPARED BY HORSM VVITTEN HEGEMANN, INC










                                                                                                                                    F-7



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                                                REFERENCES AND RESOURCES
                                                               APPENDIX G   I
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                                                         REFERENCES




                  Andreoli, A., et al. 1979. Nitrogen Removal in a Subsurface Disposal System. Journal of Water
                     Pollution Control Federation, 51, 4.

                  Association of Ground Water Scientists and Engineers. Proceedings of Ground Water Issues and
                     Solutions in the Potomac River Basin/Chesapeake Region. Washington, D.C.: George
                     Washington University, 1989.

                  Bacon, P.E. and Freney, J.R. 1989. Fertilizer Research. Vol. 20:2, P. 59-66.

                  Bal, Ganesh P. 1977. Computer Simulation Model for Groundwater Flow in the Eastern Shore of
                     Virginia. Virginia State Water Control Board. Planning Bulletin 309. 63 p.

                  Bennett, G.D., M.J. Mundorff, and S.A. Hussain. 1968. Electric-Analog Studies of Brine Coning
                     Beneath Freshwater Wells in the Punjab Region, West Pakistan. USGS WSP 1608-J. 31 pp.

                  Bock, B.R. 1984. Efficient Use of Nitrogen in Cropping Systems. In Nitrogen in Crop
                     Production, R.D. Hauck (Ed.) p.273-277.

                  Bourna, J., W.A. Ziebell, W.G. Walker, P.G. Olcott, E. McCoy, and F.D. Hole. 1972. Soil
                     Absorption of Septic Tank Effluent. University of Wisconsin-Ext. Geol. Natural History Survey
                     Information Circular No. 20.


                  Bouwer, H. 1989. Nitrogen Management and Groundwater Protection. R.F. Follett (Ed). Elsevier
                     Science Pubs. p. 363-372.

                  Brandes, M. 1978. Characteristics of Effluents from Gray and Black Water Septic Tanks. journal of
                     Water Pollution Control Federation.


                  Brown, K.W., R.L. Duble, and J.C. Thomas. 1977. Influence of Management and Season on Fate of
                     Nitrogen Applied to Golf Greens. Agronon-dc Journal 69:667-671.

                  Brown, K.W., J.C. Thomas, and R.L. Duble. 1982. Nitrogen Source on Nitrate and Ammonium
                     Leaching and Runoff Losses From Greens. Agronon-dc Journal. 74:947-950.

                  Canter and Knox. 1986. Septic System Effects on Ground Water Quality.

                  Chichester. 1977. Effects of Increased Fertilizer Rates on Nitrogen Content of Runoff and Percolate
                     From Monolith Lysimeters. Journal of Environmental Quality. 6:211-217.

                  Colman, S.M., J.P. Halka, C.H. Hobbs, 111, R.B. Mixon and D.S. Foster. 1990. Ancient Channels of
                     the Susquehanna River Beneath Chesapeake Bay and the Delmarva Peninsula. GSA Bulletin
                     102. pp. 1268-1279.

                  Douglas, D.F. 1986. Literature Review of the Cumulative Impact of On-site Sewage Disposal
                     Systems on Nitrate Nitrogen Concentrations in Ground Water. State of Vermont, Department of
                     Water Resources and Environmental Engineering, Ground Water Management Section.




                       Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                G-1








                   Dowdell & Webster. 1980. A Lysimeter Study Using Nitrogen-15 on the Uptake of Fertilizer
                      Nitrogen by Perennial Ryegrass Swards and Losses by Leaching. journal of Soil Science 31:65-
                      75.

                   Dudley, J.G., and D.A. Stephenson. 1973. Nutrient Enrichment of Ground Water From Septic Tank
                      Disposal Systems. Inland Lake Renewal and Shoreline Management Demonstration Project
                      Report. University of Wisconsin, Madison.

                   Dunne, T.D. and L.B. Leopold. 1978. Water in Environmental Planning. W.H. Freeman and
                      Company. New York. 817 p.
                   Fennema, Robert J. and Virginia P. Newton. November, 1982. Ground Water Resources of the
                      Eastern Shore of Virginia. State Water Control Board Planning Bulletin 332. 74 p and
                      Appendices.

                   Freeze, A., and J. Cherry. 1979. Groundwater. Prentice Hall, Inc., New Jersey.

                   Glover, R.E. 1959. The Pattern of Fresh-Water Flow in a Coastal Aquifer. Journal of Geophysical
                      Research. Vol. 64, No. 4. pp. 457459.

                   Ground Water Pollution News. Buraff Publications (BNA). May 25,1989.

                   Ground Water Quality Protection, State and Local Strategies. Washington, D.C., National
                      Academy Press, 1986.

                   Hesketh, E.S. 1986. The Efficiency of Nitrogen Use by Kentucky Bluegrass Turf as Influenced by
                      Nitrogen Rate, Fertilizer Ratio and Nitrification Inhibitors. M.S. Thesis, Univ. Rhode Island,
                      Kingston, RI.

                   Hubbard, R.K., Gascho, G.J. Hook, J.E. and W.G. Knisel. 1986. Nitrate Movement into Shallow
                      Ground Water Through a Coastal Plain Sand. Trans of American Society of Agricultural
                      Engineers. St. Joseph, Mich. Nov/Dec. p. 1564-1571.
                   Howie, B., and B.G. Waller. 1986. Chemical Effects of Highway Runoff on the Surficial Aquifer,
                      Broward County, Florida, USGS WRIR 864200.

                   Keeton,W.T. Biological Science. 3rd Ed. WW Norton & Co. NY 1980.
                   Koppelman, L.E. 1982. Long Island Segment of the Nationwide Urban Runoff Program, Long Island
                      Regional Planning Board, Hauppauge, N.Y.

                   Kroehler, Carolyn. What Do The Standards Mean?: A Citizens' Guide to Drinking Water
                      Contaminants. Blacksburg, VA: Virginia Tech, Virginia Water Resources Center.

                   Laak, R. 1980. Characteristics and Quantity of Wastewater. In Wastewater Engineering - Design
                      for Unsewered Areas. Ann Arbor Science Publishers, Inc.

                   Laak, Rein. 1986. Wastewater Engineering Design for Unsewered Areas. Lancaster, PA: Technomic
                      Publishing Co., Inc.
                   Lager, et. al. 1968. Urban Stormwater Management and Technology: Update and Users' Guide.
                      USEPA, 68-03-2228.



                        Ground Water Supply Protection and Manage?nent Plan for the Eastern Shore of Virginia

                                                                G-2









                  Loehr, R.C. 1974. Characteristics and Comparative Magnitude of Non-point Sources. journal of
                      Water Pollution Control Federation, 46(8).

                  Magdoff, F.R., D.R. Keeney, J. Bourna, and W.A. Ziebell. 1974. Columns Representing Mound-type
                      Disposal Systems for Septic Tank Effluent: 11. Nutrient Transformations and Bacterial
                      Populations. Journal of Environmental Quality 3(3):228-234.

                  Majumbar, S. Miller, E., and R. Parizek, eds. 1990. Water Resources in Pennsylvania:
                      Availability, Quality, and Management. Easton, PA: The Pennsylvania Academy of Science,
                      pp. 334-353: Dale E. Baker and Donald Crider, "The Environmental Consequences of Agriculture
                      in Pennsylvania".

                  Mancino, C.F. 1983. Studies of the Fate of N03- and NH4+ Nitrogen From Various Fertilizers on
                      Turf9rasses Grown on Three Different Soil Types. M.S. Thesis, University of Massachusetts-
                      Amherst.


                  McWhorter, D.B. 1972. Steady and Unsteady Flow of Fresh Water in Saline Aquifers. Water
                      Management Technical Report 20. Colorado State University. Fort Collins, Colorado. 49 p.

                  McWhorter, D.B. and D.K. Sunada. 1977. Ground-Water Hydrology and Hydraulics. Water
                      Resources Publications. Littleton, Colorado. 290 p.

                  Metcalf & Eddy, Inc. 1979. Wastewater Engineering: Treatment Disposal Reuse. McGraw Hill, Inc.

                  Miller, David W., ed. Waste Disposal Effects on Ground Water. Berkeley, California: Premier
                      Press, 1980.

                  Morton, T.G., A.J. Cold, and W.M. Sullivan, 1988. Influence of Overwatering and Fertilization on
                      Nitrogen Losses from Home Lawns. journal of Environmental Quality. 17(l):124-130.

                  Nelson, K.L., A.J. Turgeon, and J.R. Street. 1980. Thatch Influence on Mobility and Transformation
                      of Nitrogen Carriers Applied to Turf. Agronomy Journal 2:487492.

                  Nelson,M.E., S.W. Horsley, T.C. Cambareri, M. Giggey, and J. Pinette. 1988. Predicting Nitrogen
                      Concentrations in Ground Water-an Analytical Model. Proceedings of the National Water
                      Well Association, Stamford, Connecticut.

                  Owens, L.B. 1990. Nitrate-Nitrogen Concentrations in Percolate from Lysimeters
                      Planted to a Legume-Grass Mixture. journal of Environmental Quality. 19: 1,
                      131-135.


                  Petrovic, A.M. 1988. Late Fall Fertilizing and Ground Water Quality. Landscape Management,
                      1988:64.


                  Porter, K.S. 1978. Nitrates in the Long Island Comprehensive Waste Treatment Management Plan:
                      VII Summary Documentation. Long Island Regional Planning Board, Hauppauge, New York.

                  Reilly, T.E. and others. 1987. Analysis of Steady-state Salt-water Upconing with Application at
                      Truro Well Field, Cape Cod, Massachusetts. Ground Water, Vol. 25, No. 2. pp. 194-206.

                  Reneau, Jr., R.B. 1977. Changes in Inorganic Nitrogenous Compounds From Septic Tank Effluent in a
                      Soil With Fluctuating Water Table. journal of Environmental Quality, 6(2):173-178.


                       Ground Wat  er Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                G-3








                  Richardson, Donna L. 1991. Hydrogeology and Analysis of the Ground-Water-Flow System of the
                      Eastern Shore Peninsula, Virginia. Unpublished, provisional draft copy of USGS WRI 91-
                      xxxx.

                  Ritter, W.Rand , 1985. Effect of Irrigation Efficiencies on Nitrogen Leaching Losses. journal of
                      Irrigation and Drainage Engineering. Vol III, No.3.
                  Robertson, W.D., Cherry, J.A., and E.A. Sudicky. 1991. Ground-Water Contamination from Two
                      Small Septic Systems on Sand Aquifers. Ground Water: Vol. 29, No. 1, Jan-Feb 1991, p. 82-92.
                  Schmidt, S.D., and D.R. Spencer. 1986. The Magnitude of Improper Waste Discharges in an Urban
                      Stormwater System. Journal of Water Pollution Control Federation, 58(7).
                  Sinnott, Allen and G. Chase Tibbitts, Jr. 1968. Ground-Water Resources of Accomack and
                      Northampton Counties,Virginia. Virginia Division of Geology. Mineral Resources Report No.
                      9. 113 p.
                  Starr, J.L., and H.C. DeRoo. 1981. The Fate of Nitrogen Fertilizer Applied to Turf. Crop Science,
                      21:531-536.

                  Thornthwaite, C.W. and J.R. Mather. 1955. The Water Balance. Laboratory of Climatology.
                      Publication No. 8. Centerton, New Jersey.

                  U.S. Environmental Protection Agency. National Water Quality Inventory, 1988 Report to
                      Congress. April, 1990.
                  U.S. Environmental Protection Agency. On-Site Wastewater Treatment and Disposal Systems
                      Design Manual. 1980.
                  Valiela, I., and J. Costa. 1988. Eutrophication of Buttermilk Bay, a Cape Cod Coastal Embayment:
                      Concentrations of Nutrients and Watershed Nutrient Budgets. Environmental Management,
                      12(4):539-553.
                  Virginia Water Project, Inc. Water For Tomorrow. Roanoke, VA: 1988, pp. 39, 101.
                  Weigmann, Diana L. and Carolyn J. Kroehler. 1988. Threats to Virginia's Ground Water.
                      Blacksburg, VA: Virginia Tech, Virginia Water Resources Research Center.














                        Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                 G4











                                                   RESOURCES REVIEWED

                 Accomack County Comprehensive Plan, 1989.

                 Accomack County Land Use Maps, 1986.

                 Accomack County Land Use Summary (1986).

                 Accomack County Listing of Subdivisions.

                 Accomack County Map of Subdivisions.

                 Accomack County Tax Map Listing of Incorporated Towns.

                 Accomack County Tax Maps (1986).

                 Accomack County Zoning and Subdivision Ordinance.

                 Accomack-Northampton Planning District Commission. Locations of Farm Ponds for Accomack and
                 Northampton on Quadrangle Scale Maps.

                 Building Permit Data.

                 Northampton County Comprehensive Plan, 1990.

                 Northampton County Extension Service. Farm Pond Locations on Quadrangle Scale Maps.

                 Northampton County Housing Survey and Population Projection, 1988.

                 Northampton County Listing of Subdivisions.

                 Northampton County Zoning Ordinance, 1983.

                 Soil Conservation Service, 1990. Classification and Correlation of the Soils of Accomack County,
                 Virginia. October, 1990.

                 Soil Conservation Service. Hydrologic Unit Maps of Accomack and Northampton Counties.
                 1:126,720 scale.

                 Soil Conservation Service (United States Department of Agriculture). Soil Survey of Northampton
                 County, Virginia. August, 1989.

                 Virginia Bureau of Toxic Substances Information. Commercial Use of Substances by Establishment,
                 Accomack and Northampton Counties.

                 Virginia Department of Agriculture. Virginia Pesticide Law and Regulations, 1986.

                 Virginia Department of Agriculture. Restricted Use Pesticides, 1990.

                 Virginia Department of Agriculture and Conservation Service. Pesticide Use Estimate 1990.




                     Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                              G-5







                     Virginia Department of Health. Base Line Water Quality Study of Shallow Wells in
                     Northampton and Accomack Counties, April 1990.

                     Virginia Department of Health. List of Transient-Public Water Users.

                     Virginia Department of Health. Listing of Migrant Labor Camps.

                     Virginia Department of Health. Map of Migrant Labor Camp Locations.
                     Virginia Division of Geology. Summary of Geology and Ground-Water Resources of the Eastern
                     Shore Peninsula, Virginia, A Preliminary Report. Mineral Resources Circular No. 2,1954.
                     Virginia Division of Mineral Resources. Geologic Studies, Coastal Plain of Virginia, Bulletin 83
                     (Part 3), 1973.

                     Virginia Division of Mineral Resources. Ground-Water Resources of Accomack and Northampton
                     Counties, Virginia Mineral Resources Report No. 9,1968.
                     Virginia State Water Control Board. Computer Simulation Model for Groundwater Flow in the
                     Eastern Shore of Virginia, Planning Bulletin 309, 1977.
                     Virginia State Water Control Board. Eastern Shore Water Supply Plan. Planning Bulletin 342,
                     March 1988.

                     Virginia State Water Control Board. Groundwater Conditions in the Eastern Shore Groundwater
                     Management Area, Virginia. Planning Bulletin 45, Supplement No. 2
                     Virginia State Water Control Board. Groundwater Conditions in the Eastern Shore of Virginia.
                     Planning Bulletin 45, December 1975.
                     Virginia State Water Control Board.   Ground Water Resources of the Eastern Shore of Virginia.
                     Planning Bulletin 332, November 1982.
                     Virginia State Water Control Board. Virginia Eastern Shore Water Quality Management Plan,
                     1980.

                     Virginia State Water Control Board. Virginia Livestock and Poultry Water Use Basic Data.
                     Bulletin 60, 1983.

                     Virginia Tech. Hydric Soils Maps. 1:100,00 scale.
                     Virginia Tech, Virginia Water Resources Research Center. Facts About Virginia's Groundwater,
                     1988.

                     Virginia Tech, Virginia Water Resources Research Center. A Groundwater Primer for Virginians,
                     1984.

                     Virginia Tech, Virginia Water Resources Research Center. A Homeowner's Guide to Domestic
                     Wells, 1985.

                     Virginia Tech, Virginia Water Resources Research Center. A Homeowner's Guide to Septic
                     Systems, 1985.


                          .Ground Water Supply Protection and Management Plan for the Eastern Shore of Virginia
                                                                       G-6









                 Virginia Tech, Virginia Water Resources Research Center. Listing of Mass Drainfields on the
                 Eastern Shore, 1985.

                 Virginia Tech, Virginia Water Resources Research Center. Protecting Virginia's Groundwater,
                 1986.


                 Virginia Tech, Virginia Water Resources Research Center. Sandcastles, Moats, and Petunia Bed
                 Holes, a Book About Groundwater, 1986.

                 Virginia Tech, Virginia Water Resources Research Center. Threats to Virginia's Groundwater,
                 1988.

                 United States Bureau of the Census. 1990 Population Figures.

                 United States Geological Survey. Groundwater Quality Assessment of the Delmarva Peninsula,
                 Delaware, Maryland, and Virginia-Analysis of Available Water Quality Data Through 1987.
                 Open File Report 89-34, 1989.

                 Wallops Island Well Boring Logs, Impact Statement (2 documents).


































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