[Federal Register Volume 64, Number 83 (Friday, April 30, 1999)]
[Proposed Rules]
[Pages 23398-23458]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-10001]



[[Page 23397]]

_______________________________________________________________________

Part II





Environmental Protection Agency





_______________________________________________________________________



40 CFR Parts 141 and 142



Revisions to the Unregulated Contaminant Monitoring Regulation for 
Public Water Systems; Proposed Rule

  Federal Register / Vol. 64, No. 83 / Friday, April 30, 1999 / 
Proposed Rules  

[[Page 23398]]



ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 141 and 142

[FRL-6329-3]
RIN 2040-AD15


Revisions to the Unregulated Contaminant Monitoring Regulation 
for Public Water Systems

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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

SUMMARY: The Safe Drinking Water Act (SDWA), as amended in 1996, 
requires the Environmental Protection Agency (EPA) to establish 
criteria for a monitoring program for unregulated contaminants and, by 
August 6, 1999, to publish a list of contaminants to be monitored. To 
conform to the Amendments, EPA is proposing the Unregulated Contaminant 
Monitoring Regulation for Public Water Systems (UCMR) to substantially 
revise the current regulations for unregulated contaminant monitoring.
    Under a separate action on January 8, 1999, EPA published a Direct 
Final Rule suspending the existing monitoring requirements for systems 
serving 10,000 or fewer persons, effective March 9, 1999. Prior to 
March 9, 1999, the unregulated contaminant monitoring regulations 
required public water systems to monitor for unregulated contaminants 
during one year every five years. EPA promulgated the direct final rule 
to allow systems serving 10,000 or fewer persons to save the cost of a 
third monitoring round under the previous regulations, which if 
performed as scheduled would have overlapped with monitoring 
requirements expected to be promulgated in the UMCR in August 1999.
    This proposed rule includes a new list of contaminants to be 
monitored, procedures for selecting a national representative sample of 
public water systems serving 10,000 or fewer persons that will be 
required to monitor, the frequency and schedule for monitoring, and 
procedures for placement of the monitoring data in the National 
Drinking Water Contaminant Occurrence Data Base, as required under 
section 1445 of SDWA, as amended. The data in the database will be used 
to identify contaminants for the Drinking Water Contaminant Candidate 
List (CCL), to support the Administrator's determination of whether or 
not to develop drinking water standards for a particular contaminant, 
and in developing standards for the contaminants the Administrator 
selects.

DATES: The proposed rule is open to public comment until June 14, 1999.

ADDRESSES: Send written comments to the Comment Clerk, docket number W-
98-02, U.S. Environmental Protection Agency, Water Docket (MC 4101), 
401 M Street, SW, Washington, DC 20460. Please submit an original and 
three copies of your comments and enclosures (including references). 
Commenters who want EPA to acknowledge receipt of their comments should 
enclose a self-addressed, stamped envelope. No facsimiles (faxes) will 
be accepted.
    Comments may also be submitted electronically to ow-
[email protected]. Electronic comments must be submitted as an 
ASCII file avoiding the use of special characters and any form of 
encryption. Electronic comments must be identified by the docket number 
W-98-02. Comments and data will also be accepted on disks in 
WordPerfect in 5.1 format or ASCII file format. Electronic comments on 
this proposal may be filed online at many Federal Depository Libraries.
    The full record for this proposal has been established under docket 
number W-98-02 and includes supporting documentation as well as 
printed, paper versions of electronic comments. The full record is 
available for inspection from 9 a.m. to 4 p.m. Monday through Friday, 
excluding legal holidays at the Water Docket, East Tower Basement, 
USEPA, 401 M Street, SW, Washington DC. For access to docket materials, 
please call (202) 260-3027 between 9 a.m. and 3:30 p.m, Eastern Time, 
Monday through Friday, to schedule an appointment.

FOR FURTHER INFORMATION CONTACT: Charles Job, Standards and Risk 
Management Division, Office of Ground Water and Drinking Water (MC-
4607), U.S. Environmental Protection Agency, 401 M Street, SW, 
Washington DC 20460, (202) 260-7084. General information may also be 
obtained from the EPA Safe Drinking Water Hotline. Callers within the 
United States may reach the Hotline at (800) 426-4791. The Hotline is 
open Monday through Friday, excluding federal holidays, from 9 a.m. to 
5:30 p.m. Eastern Time.

SUPPLEMENTARY INFORMATION:

Regional Contacts

I. Anthony De Palma, JFK Federal Bldg., Room 2203, Boston MA 02203, 
Phone: 617-565-3610.
II. Walter Andrews, 290 Broadway, Room 2432, New York, NY 10007-
1866, Phone: 212-637-3880.
III. Michelle Hoover, 1650 Arch Street, Philadelphia PA 19103-2029, 
Phone: 215-814-5258.
IV. Janine Morris, 345 Courtland Street, NE, Atlanta GA 30365, 
Phone: 404-562-9480.
V. Kim Harris, 77 West Jackson Blvd., Chicago, IL 60604-3507, Phone: 
312-886-4239.
VI. Larry Wright, 1445 Ross Avenue, Dallas, TX 75202, Phone: 214-
665-7150.
VII. Stan Calow, 726 Minnesota Ave., Kansas City, KS 66101, Phone: 
913-551-7410.
VIII. Rod Glebe, One Denver Place, 999 18th Street, Suite 500, 
Denver, CO 80202, Phone: 303-312-6627.
IX. Bruce Macler, 75 Hawthorne Street, San Francisco, CA 94105, 
Phone: 415-744-1884.
X. Larry Worley, 1200 Sixth Avenue, Seattle, WA 98101, Phone: 206-
553-1893.

Abbreviations and Acronyms Used in the Preamble and Proposed Rule

2,4-DNT--2,4-dinitrotoluene
2,6-DNT--2,6-dinitrotoluene
4,41'-DDE--degradation product of DDT
Alachlor ESA--alachlor ethanesulfonic acid, a degradation product of 
alachlor
AOAC--Association of Official Analytical Chemist
ASDWA--Association of State Drinking Water Administrators
ASTM--American Society for Testing and Materials
BGM--Buffalo Green Monkey cells, a specific cell line used to grow 
viruses
CAS--Chemical Abstract Service
CASRN--Chemical Abstract Service Registry Number
CCL--Contaminant Candidate List
CCR--Consumer Confidence Reports
CERCLA--Comprehensive Environmental Response, Compensation and 
Liability Act
CFR--Code of Federal Regulations
CFU--Colony forming unit
CFU/mL--Colony forming units per milliliter
CWS--Community water system
DCPA--dimethyl tetrachloroterephthalate, chemical name of the 
herbicide dacthal DCPA di- and mono-acid degradates
    --Degradation products of DCPA
DDE--Degradation product of DDT
DDT--Dichloro diphenyl trichloroethane, a general insecticide
EDL--Estimated detection limit
EPA--Environmental Protection Agency
EPTC--s-ethyl-dipropylthiocarbamate, an herbicide
EPTDS--Entry Point to the Distribution System
FACA--Federal Advisory Committee Act
FTE--Full-time-equivalent
GC--Gas chromatography, a laboratory method
GLI method--Great Lakes Instruments method
GW--Ground water
GWUDI--Ground water under the direct influence of surface water
HLPC--High performance liquid chromatography, a laboratory method
ICR--Information Collection Request
IFRA--Initial regulatory flexibility analysis
IMS--Immunomagnetic separation

[[Page 23399]]

IRIS--Integrated Risk Information System
IS--Internal standard
LLE--Liquid/liquid extraction, a laboratory method
MAC--Mycobacterium avium intracellulare
MCL--Maximum contaminant level
MDL--Method detection limit
MRL--Minimum reporting level
MS--Mass spectrometry, a laboratory method
MS--Sample matrix spike
MSD--Matrix spike duplicate
MTBE--Methyl-tert-butyl-ether, a gasoline additive
NAWQA--National Water Quality Assessment Program
NCOD--National Drinking Water Contaminant Occurrence Data Base
NDWAC--National Drinking Water Advisory Council
NERL--National Environmental Research Laboratory
NPS--National Pesticide Survey
NTIS--National Technical Information Service
NTNCWS--Non-transient non-community water system
NTTAA--National Technology Transfer and Advancement Act
OGWDW--Office of Ground Water and Drinking Water
OMB--Office of Management and Budget
PBMS--Performance-Based Measurement System
pCi/L--Picocuries per liter
PCR--Polymerase chain reaction
PWS--Public Water System
PWSF--Public Water System Facility
QA--Quality assurance
QC--Quality control
RDX--Hexahydro-1,3,5-trinitro-1,3,5-triazine
RFA--Regulatory Flexibility Act
RPD--Relative percent difference
RSD--Relative standard deviation
SBREFA--Small Business Regulatory Enforcement Fairness Act
SD--Standard deviation
SDWA--Safe Drinking Water Act
SDWIS--Safe Drinking Water Information System
SDWIS FED--the Federal Safe Drinking Water Information System
SM--Standard Methods
SMF--Standard Compliance Monitoring Framework
SOC--Synthetic organic compound
SPE--Solid phase extraction, a laboratory method
SRF--State Revolving Fund
STORET--Storage and Retrieval System
SW--surface water
TBD--to be determined
TNCWS--Transient non-community water system
UCMR--Unregulated Contaminant Monitoring Regulations/Rule
UCM--Unregulated Contaminant Monitoring
ug/L--Micrograms per liter
UMRA--Unfunded Mandates Reform Act of 1995
USEPA--United States Environmental Protection Agency
UV--Ultraviolet
VOC--volatile organic compound

Preamble Outline

I. Why the Unregulated Contaminant Monitoring Regulation Is Changing
II. Current Unregulated Contaminant Monitoring
    A. Current Program
    B. Status of Unregulated Contaminants on the Current Monitoring 
List
III. Proposed Changes in the Unregulated Contaminant Monitoring 
Program
    A. Revised List of Unregulated Contaminants to be Monitored
    1. Criteria for Selecting Contaminants for the UCMR
    (a) Revising the Monitoring List
    (b) Regulatory Options
    (c) Analytical Methods Applicable to the Monitoring List
    (i) Chemical Analytical Methods
    (ii) Microbiological Analytical Methods
    (d) Screening Methods
    2. List of Contaminants To Be Monitored
    (a) Proposed Monitoring List
    (b) Number of Contaminants on the Monitoring List
    (c) Modifying the Monitoring List through the Governors' 
Petition
    (i) Circumstances Affecting the Governors' Petition
    (ii) Response to Governors' Petition
    B. Public Water Systems Subject to the UCMR
    C. Type of Monitoring Required of Public Water Systems Based on 
Listing Group
    1. Assessment Monitoring
    2. Screening Survey
    3. Pre-Screen Testing
    4. Option to the Three-Tiered Approach
    D. Monitoring Requirements under the Proposed UCMR
    1. Monitoring Frequency
    (a) Systems Serving more than 10,000 persons
    (b) Systems Serving 10,000 or fewer persons
    2. Monitoring Time for Vulnerable Period
    3. Monitoring Location
    (a) Chemical Contaminants
    (b) Microbiological Contaminants
    4. Quality Control Procedures for Sampling and Testing
    5. Monitoring of Routinely Tested Water Quality Parameters
    6. Relations to Compliance Monitoring Requirements
    7. Previous Monitoring of the Contaminants Proposed for the 
Monitoring List
    8. Regulatory Options considered for large systems
    (a) Which large systems should monitor
    (b) Monitoring Frequency
    (c) Monitoring Location
    E. Waivers
    1. Waivers for Systems Serving more than 10,000 Persons
    2. Waivers for Small Systems in State Plans
    F. Representative sample of systems serving 10,000 or fewer 
persons
    1. System Size
    2. System Type
    (a) Public Water System Monitoring
    (b) Non-Transient Non-Community Water Systems
    (c) Transient Non-Community Systems
    3. Geographic location within the State
    4. Likelihood of Finding Contaminants
    5. State Plans for the Representative Sample
    (a) Representative State Plans
    (b) Systems Selected for Pre-Screen Testing
    (c) Tribal Water Systems as a Separate Group
    (d) ``Index'' Systems
    (e) Other State Data
    6. Regulatory Options
    G. Reporting of Monitoring Results
    1. PWS and State Reporting to EPA
    2. Regulatory Options
    3. Timing of Reporting
    4. Method of Reporting
    5. Public Notification of Availability of Results
    6. Voluntary Reporting
IV. Implementation of Today's Proposal
    A. Setting an Effective Date
    B. Primary Program Revision
    C. Implementation in Indian Country
    D. Establishing the Laboratory Testing Program
    1. Analytical Methods for the Testing Program
    2. Testing Program for systems serving more than 10,000 persons
    3. Testing Program for systems serving 10,000 or fewer persons
    E. Continued Analytical Methods Development
    F. Determining the National Representative Sample and State 
Monitoring Plans
    G. Specifying the Vulnerable Monitoring Period
    H. Conducting the Sampling
    I. Screening Survey
    J. Pre-Screen Testing
    K. Testing
    L. Reporting Requirements
    M. Record Keeping
    N. Modifying the Monitoring List
    O. Funding for Testing of Sample for Systems in State Monitoring 
Plans and for Pre-Screen Testing
    (1) Assessment Monitoring
    (2) Screening Survey.
    (3) Pre-Screen Testing
V. Relation of the Proposed Regulation to the Existing Regulation
VI. Cost and Benefit of a Revised UCMR Program
    A. Program Cost Estimates
    B. Net Costs
    C. Benefits
VII. Performance-Based Measurement System
VIII. Solicitation of Public Comment
IX. Administrative Requirements
    A. Executive Order 12866--Regulatory Planning and Review
    B. Executive Order 13045--Protection of Children From 
Environmental Health Risks and Safety Risks
    C. Unfunded Mandates Reform Act
    D. Paperwork Reduction Act
    E. Regulatory Flexibility Act
    F. National Technology Transfer and Advancement Act
    G. Executive Order 12898--Federal Actions to Address 
Environmental Justice in Minority Populations and Low-Income 
Populations

[[Page 23400]]

    H. Executive Order 12875--Enhancing Intergovernmental 
Partnerships
I. Executive Order 13084--Consultation and Coordination with Indian 
Tribal Governments
X. Public Involvement in Regulation Development
XI. References

Potentially Regulated Entities

    The regulated entities are public water systems. All large 
community and non-transient non-community water systems serving more 
than 10,000 persons would be required to monitor. A community water 
system means a public water system which serves at least 15 public 
service connections used by year-round residents or regularly serves at 
least 25 year-round residents. Non-transient non-community water system 
means a public water system that is not a community water system and 
that regularly serves at least 25 of the same persons over 6 months per 
year. Only a national representative sample of community and non-
transient non-community systems serving 10,000 or fewer persons would 
be required to monitor. Transient non-community systems (i.e., systems 
that do not regularly serve at least 25 of the same persons over six 
months per year) would not be required to monitor. States, Territories, 
and Tribes with primacy to administer the regulatory program for public 
water systems under the Safe Drinking Water Act, sometimes conduct 
analyses to measure for contaminants in water samples and would be 
regulated by this action. Categories and entities that may ultimately 
be regulated include the following:

------------------------------------------------------------------------
                                     Examples of potentially
           Category                    regulated entities           SIC
------------------------------------------------------------------------
State, Tribal and Territorial   States, Territories, and Tribes     9511
 Governments.                    that analyze water samples on
                                 behalf of public water systems
                                 required to conduct such
                                 analysis; States, Territories,
                                 and Tribes that themselves
                                 operate community and non-
                                 transient non-community water
                                 systems required to monitor.
Industry......................  Private operators of community      4941
                                 and non-transient non-community
                                 water systems required to
                                 monitor.
Municipalities................  Municipal operators of community    9511
                                 and non-transient non-community
                                 water systems required to
                                 monitor.
------------------------------------------------------------------------

    This table is not intended to be exhaustive, but rather provides a 
guide for readers regarding entities likely to be regulated by this 
action. This table lists the types of entities that EPA is now aware 
could potentially be regulated by this action. Other types of entities 
not listed in the table could also be regulated. If you have questions 
regarding the applicability of this action to a particular entity, 
consult the person listed in the preceding FOR FURTHER INFORMATION 
CONTACT section.

I. Why the Unregulated Contaminant Monitoring Regulation Is 
Changing

    The current Unregulated Contaminant Monitoring Program operating 
under the Safe Drinking Water Act (SDWA, the Act) requires public water 
systems to monitor for unregulated contaminants during one year every 
five years. Under section 1445(a)(2) of the Act, as amended in 1996, 
the Environmental Protection Agency (EPA) is required to establish 
criteria for a monitoring program for unregulated contaminants and, by 
August 6, 1999, to publish a list of contaminants to be monitored. To 
conform to the 1996 Amendments, EPA is proposing substantial revisions 
to the Unregulated Contaminant Monitoring (UCM) Program, currently 
described in 40 CFR 141.40. The purpose of the Unregulated Contaminant 
Monitoring Program is to collect occurrence data to help determine 
which contaminants EPA should regulate based on their concentrations in 
public water systems and their adverse health effects levels.
    This proposed rule will take the place of the regulations currently 
in 40 CFR 141.35, 141.40, and 142.15(c)(3) and modify Sec. 142.16. The 
revisions cover the following: (1) The frequency and schedule for 
monitoring based on public water system (PWS) size, water source, and 
likelihood of finding the contaminants; (2) a new shorter list of 
contaminants to be monitored, (3) procedures for selecting and 
monitoring a national representative sample of public water systems 
serving 10,000 or fewer people, and (4) procedures for placing the 
monitoring data in the National Drinking Water Contaminant Occurrence 
Data Base (NCOD), as required under Section 1445. The data generated by 
this rule, when adopted, will be used to identify contaminants for the 
Contaminant Candidate List (CCL), to support the Administrator's 
determination of whether or not to regulate a contaminant under the 
drinking water program, and to support the development of drinking 
water regulations. The proposed revised UCM Program is a cornerstone of 
the sound science approach to future drinking water regulation, which 
is one of the aims of the SDWA Amendments.
    In a separate action, EPA has published a Direct Final Rule (64 FR 
1494, January 8, 1999) which will cancel the existing monitoring 
requirements for systems serving 10,000 or fewer persons effective 
January 1, 1999. The Direct Final Rule will modify the existing 
regulations ahead of this Proposed Rule to revise the existing 
unregulated contaminant monitoring regulations. The Direct Final Rule's 
purpose is to allow the systems serving 10,000 or fewer persons to save 
the cost of a third monitoring round under the existing regulation, 
which if performed would overlap with monitoring under the proposed 
revised rule. EPA believes that it has sufficient data from the 
previous monitoring rounds to make decisions concerning the status of 
the contaminants on the existing monitoring list (see Table 1).

II. Current Unregulated Contaminant Monitoring

A. Current Program

    The current Unregulated Contaminant Monitoring Program was 
established in the SDWA, as amended in 1986, and implemented by 
regulation in 1987 (52 FR 25720, July 8, 1987). The program was revised 
three times thereafter (56 FR 3526, January 30, 1991; 57 FR 22178, May 
27, 1992; and 57 FR 31776, July 17, 1992). Under 40 CFR 141.40, public 
water systems are required to monitor for up to 48 unregulated 
contaminants and under 40 CFR 141.35, to report monitoring results to 
the States, or to EPA if a State does not have primacy to administer 
the State Drinking Water Program. These 48 contaminants are listed in 
Table 1 of this Preamble, along with their regulatory status. Under 40 
CFR 142.15, primacy States must report monitoring results to EPA. 
Repeat monitoring and reporting are required during one year every 5 
years. Systems serving fewer than 150 service connections may make 
their facilities available for the States to monitor, rather than 
perform their own monitoring.

B. Status of Unregulated Contaminants on the Current Monitoring List

    Based on the results of the current Unregulated Contaminant 
Monitoring

[[Page 23401]]

Program, EPA analyzed each of the 48 contaminants on the current list. 
The status of the 48 contaminants as a result of that analysis is 
summarized below in Table 1.

                                            Table 1.--List and Status of the Current Unregulated Contaminants
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                           Covered by
                                                                      In regulation    On contaminant   Did not occur        other         Did not meet
                                                                     development \1\   candidate list   at significant     regulatory     health effects
                                                                                            \2\           levels \3\       action \4\       level \5\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Aldicarb...........................................................               X
Aldicarb sulfone...................................................               X
Aldicarb sulfoxide.................................................               X
Aldrin.............................................................  ...............               X
Bromobenzene.......................................................  ...............               X
Bromochloromethane.................................................               X
Bromodichloromethane...............................................               X
Bromoform..........................................................               X
Bromomethane (methyl bromide)......................................  ...............               X
Butachlor..........................................................  ...............  ...............               X
sec-Butylbenzene...................................................  ...............  ...............  ...............  ...............               X
n-Butylbenzene.....................................................  ...............  ...............  ...............  ...............               X
tert-Butylbenzene..................................................  ...............  ...............  ...............  ...............               X
Carbaryl...........................................................  ...............  ...............               X
Chlorodibromomethane...............................................               X
Chloroethane.......................................................               X
Chloroform.........................................................               X
Chloromethane......................................................               X
o-Chlorotoluene....................................................  ...............  ...............               X
p-Chlorotoluene....................................................  ...............  ...............               X
Dibromomethane.....................................................               X
Dicamba............................................................  ...............  ...............               X
m-Dichlorobenzene..................................................  ...............  ...............               X
Dichlorodifluoromethane............................................  ...............  ...............               X
1,1-Dichloroethane.................................................  ...............               X
2,2-Dichloropropane................................................  ...............               X
1,3-Dichloropropane................................................  ...............               X
1,1-Dichloropropene................................................  ...............               X
1,3-Dichloropropene................................................  ...............               X
Dieldrin...........................................................  ...............               X
Fluorotrichloromethane.............................................  ...............  ...............               X
Hexachlorobutadiene................................................  ...............               X
3-Hydroxycarbofuran................................................  ...............  ...............  ...............               X
Isopropylbenzene...................................................  ...............  ...............               X
p-Isopropyltoluene.................................................  ...............               X
Methomyl...........................................................  ...............  ...............               X
Metolachlor........................................................  ...............               X
Metribuzin.........................................................  ...............               X
Naphthalene........................................................  ...............               X
Propachlor.........................................................  ...............  ...............               X
n-Propylbenzene....................................................  ...............  ...............               X
Sulfate............................................................  ...............               X
1,1,1,2-Tetrachloroethane..........................................  ...............  ...............               X
1,1,2,2-Tetrachloroethane..........................................  ...............               X
1,2,3-Trichlorobenzene.............................................  ...............  ...............  ...............               X
1,2,3-Trichloropropane.............................................  ...............  ...............               X
1,2,4-Trimethylbenzene.............................................  ...............               X
1,3,5-Trimethylbenzene.............................................  ...............  ...............  ...............  ...............               X
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ In Regulation Development means that EPA is currently working on regulations affecting the contaminant in drinking water.
\2\ On Contaminant Candidate List means that the contaminant is on the CCL for EPA to determine whether or not to regulate it in the future.
\3\ Did Not Occur at Significant Levels means that unregulated contaminant monitoring results and other data did not indicate widespread occurrence or
  concentrations that would warrant further action.
\4\ Covered By Other Regulatory Action means that the contaminant is addressed through regulation of other contaminants.
\5\ Did Not Meet Health Effects Level means that the concentrations reported in unregulated contaminant monitoring results or other data were not at or
  above health effects levels established by EPA or other organizations that have such health indicators.


[[Page 23402]]

III. Proposed Changes in the Unregulated Contaminant Monitoring 
Program

A. Revised List of Unregulated Contaminants To Be Monitored

1. Criteria for Selecting Contaminants for the UCMR
(a) Revising the Monitoring List
    Section 1445(a)(2)(B) requires EPA to list not more than 30 
unregulated contaminants to be monitored by public water systems. Today 
EPA is proposing to use the Contaminant Candidate List (CCL), 
established under section 1412(b)(1)(B) of SDWA, as the primary basis 
for selecting contaminants for future monitoring under the UCMR. The 
criteria used in the CCL for identifying contaminants for which 
occurrence data are needed are:
    (i) Whether sufficient data exist on the occurrence or likely 
occurrence of the contaminant in drinking water, including production, 
release, and use to warrant further confirming data; and
    (ii) Whether sufficient data exist to indicate the occurrence of 
the contaminant in two or more States, or in ten or more public water 
systems.
    The other criterion is whether an analytical method exists for the 
contaminant. The other mechanism for selecting contaminants for UCMR 
monitoring is through the petition of seven or more State governors to 
EPA, described below under III.A.2.(c), Modifying the Monitoring List 
through the Governors' Petition.
    The CCL was developed with the advice of the Working Group on 
Contaminant Occurrence and Selection of the National Drinking Water 
Advisory Council (NDWAC), formed pursuant to the Federal Advisory 
Committee Act (FACA). The group developed criteria, adopted by EPA, for 
deciding which contaminants to include on the CCL.
    Criteria for selecting contaminants for the CCL focused on 
occurrence in water at levels of health concern, or indications of 
occurrence (production or release, coupled with contaminant 
properties). EPA used health effects concentrations to determine the 
significance of occurrence levels. When developing the CCL, EPA used 
the previous unregulated contaminant monitoring data from States as one 
of the many sources of occurrence data. The term ``occurrence'' as used 
here means the measured observation of a substance in drinking water or 
potential source of drinking water. The 1998 CCL contains 50 chemical 
contaminants and 10 microbiological contaminants. The process for 
developing the CCL is described in more detail in the March 2, 1998, 
Federal Register containing the list (63 FR 10273).
    When EPA began the process of choosing contaminants for the CCL, 
EPA and NDWAC experts worked from a compendium of 8 lists containing 
approximately 262 chemical contaminants. The lists used in this process 
included the 1991 Drinking Water Priority List, health advisories, 
Integrated Risk Information System, Non-Target Analytes in Public Water 
Supply Samples, Comprehensive Environmental Response, Compensation and 
Liability Act (CERCLA) Priority List, stakeholder responses, Toxic 
Release Inventory, and pesticides identified by the Office of Pesticide 
Programs. Contaminants not among the 262 chemical contaminants 
initially identified were not considered in developing the CCL.
    Table 2 lists all of the contaminants on the CCL and indicates 
whether they are priorities for consideration under three categories--
regulation, research (health, treatment, and analytical methods), and 
occurrence. (Contaminants may appear in more than one column of Table 
2.) The groupings in Table 2 are based on current (1998) information, 
and some movement of contaminants between categories can be expected as 
more information is evaluated and analyzed. In Table 2, ``Regulation 
Determination Priorities'' means that for the contaminants listed, EPA 
believes it has or will soon have sufficient data to determine whether 
or not to regulate these contaminants. ``Research Priorities'' means 
that before EPA could make any regulatory determination, EPA would need 
health effects data, treatment technology results, or analytical 
methods development to test for the contaminants. ``Occurrence 
Priorities'' indicates that EPA needs data to determine whether the 
contaminant occurs or is likely to occur in drinking water of public 
water systems. The ``Occurrence Priorities'' identify the contaminants 
that EPA is focusing on in the Unregulated Contaminant Monitoring 
Program proposed today. EPA believes that the purpose of this program 
is to compile data concerning the occurrence of unregulated 
contaminants in drinking water so that, together with health effects 
information, EPA can determine which unregulated contaminants are 
priorities for future regulation.

[[Page 23403]]



                                   Table 2.--Contaminant Candidate List (CCL)
----------------------------------------------------------------------------------------------------------------
                                               Research priorities
      Regulatory      ---------------------------------------------------------------------      Occurrence
    determination                                                      Analytical methods        priorities
      priorities          Health research       Treatment research          research
----------------------------------------------------------------------------------------------------------------
Acanthamoeba           Aeromonas hydrophila   Adenoviruses           Adenoviruses           Adenoviruses
 (guidance)            Cyanobacteria (Blue-   Aeromonas hydrophila   Cyanobacteria (Blue-   Aeromonas hydrophila
1,1,2,2-                green algae), other   Cyanobacteria (Blue-    green algae), other   Cyanobacteria (Blue-
 tetrachloroethane      freshwater algae,      green algae), other    freshwater algae,      green algae), other
1,1-dichloroethane      and their toxins       freshwater algae,      and their toxins       freshwater algae,
1,2,4-                 Caliciviruses           and their toxins      Caliciviruses           and their toxins
 trimethylbenzene      Helicobacter pylori    Caliciviruses          Helicobacter pylori    Caliciviruses
1,3-dichloropropene    Microsporidia          Coxsackieviruses (ICR  Microsporidia          Coxsackieviruses
2,2-dichloropropane    Mycobacterium avium     data)                 1,2-diphenylhydrazine   (ICR data)
Aldrin                  intercellulare (MAC)  Echoviruses (ICR       2,4,6-trichlorophenol  Echoviruses (ICR
Boron                  1,1-dichloropropene     data)                 2,4-dichlorophenol      data)
Bromobenzene           1,3-dichloropropane    Helicobacter pylori    2,4-dinitrophenol      Helicobacter pylori
Dieldrin               Aluminum               Microsporidia          2-methyl-Phenol        Microsporidia
Hexachlorobutadiene    DCPA mono-acid and di- Mycobacterium avium    Acetochlor             1,2-
p-Isopropyltoluene      acid degradates        intracellulare (MAC)  Alachlor ESA            diphenylhydrazine
Manganese              Methyl bromide         Aluminum               Fonofos                2,4,6-
Metolachlor            MTBE                   MTBE                   Perchlorate             trichlorophenol
Metribuzin             Perchlorate            Perchlorate            RDX                    2,4-dichlorophenol
Naphthalene            Sodium (guidance)                                                    2,4-dinitrophenol
Organotins                                                                                  2,4-dinitrotoluene
Triazines and                                                                               2,6-dinitrotoluene
 degradation products                                                                       2-methyl-phenol
 (incl., but not                                                                            Alachlor ESA
 limited to Cyanazine                                                                       Acetochlor
 and atrazine-                                                                              DCPA mono-acid and
 desethyl)                                                                                   di-acid degradates
Sulfate                                                                                     DDE
Vanadium                                                                                    Diazinon
                                                                                            Disulfoton
                                                                                            Diuron
                                                                                            EPTC
                                                                                            Fonofos
                                                                                            Linuron
                                                                                            Molinate
                                                                                            MTBE
                                                                                            Nitrobenzene
                                                                                            Perchlorate
                                                                                            Prometon
                                                                                            RDX
                                                                                            Terbacil
                                                                                            Terbufos
----------------------------------------------------------------------------------------------------------------

    The CCL lists 26 chemical and 8 microbiological contaminants as 
occurrence priorities because additional data on their occurrence in 
drinking water are needed to help decide whether or not to regulate 
them. Today's proposal does not address the two contaminants identified 
in the preparation of the CCL as highly localized in occurrence: 
Perchlorate and RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine). During 
the process of identifying contaminants for the CCL and subsequently 
for the UCMR, perchlorate had only been detected at a few sites in the 
western U.S. However, perchlorate is increasingly being detected in 
other parts of the country. A total of nine States have detected 
perchlorate and as monitoring increases, other States are likely to 
detect it. EPA seeks public comment on whether perchlorate and RDX 
should be included in the UCM List.
    For the remaining 32 contaminants on the CCL Occurrence Priorities 
List, EPA has evaluated the availability of analytical methods 
published by EPA or voluntary consensus standards organizations such as 
the American Society for Testing and Materials (ASTM) and Standard 
Methods (SM). In addition, EPA prioritized analytical methods 
development activities for those compounds and microbiological 
parameters for which suitable analytical methods are not currently 
available. As listed in List 1 of Table 3 below, EPA identified 10 
organic chemical contaminants and one microbiological contaminant for 
which analytic methods are now available. List 1 contaminants are those 
that are proposed today to be monitored beginning on the effective date 
of this rule, as explained in 2., List of Contaminants to be Monitored. 
List 2 of Table 3 lists 14 organic chemical contaminants for which 
methods are being refined. List 3 of Table 3 identifies seven 
microbiological contaminants for which methods are being researched. 
Contaminants on Lists 2 and 3 are not proposed to be monitored until 
EPA promulgates revisions to this rule to specify analytical methods 
and related sampling requirements.
    In addition, EPA requests comment on the addition to the 
unregulated contaminant monitoring List 1 of two naturally occurring 
radionuclides with health concerns at low levels, Lead-210 (Pb-210), 
and Polonium-210 (Po-210). Both nuclides are in the uranium decay 
series along with radium-226 and radon-222. Lead-210 with a half life 
of 22 years, and one of its progeny, polonium-210, with a half life of 
138 days, have been found in drinking water. EPA is aware of the 
occurrence of these contaminant in shallow aquifers in Florida (Harada, 
et al., 1989; Upchurch, 1991), and in at least two other states. 
Because of potential occurrence and consequent health risks, EPA is 
considering adding these contaminants to the monitoring list.

[[Page 23404]]

(b) Regulatory Options
    EPA proposes in Sec. 141.40(a)(3) that the contaminants listed in 
Lists 1-3 be used for the UCMR program monitoring list and be 
categorized based on the availability of analytical methods. List 1 is 
the basis for ``Assessment Monitoring.'' EPA proposes that ``Assessment 
Monitoring'' occur at all 2,774 large community and non-transient non-
community systems serving more than 10,000 persons and a representative 
sample of approximately 800 systems serving less than 10,000 or fewer 
persons in State Monitoring Plans. List 2 will be the basis of a 
``Screening Survey'' of approximately 300 of the systems required to do 
Assessment Monitoring. List 3 will be used for ``Pre-Screen Testing'' 
at up to 200 systems selected because of potential vulnerability to the 
specific contaminants. This monitoring approach is described in detail 
under III.C. ``Type of Monitoring Required of Public Water Systems 
Based on Listing Group.'' Assessment Monitoring would include only 
those contaminants in List 1 for which analytical methods are included 
in this regulation. Assessment Monitoring (and associated ``index 
site'' monitoring described below) is the only monitoring that would be 
required by today's proposal. This includes contaminants for which EPA 
expects to have developed reference analytical methods by the year 
2000.
    For contaminants in List 2 for which analytical methods are 
developed by the time of initial monitoring in 2001, EPA would amend 
this rule to require the Screening Survey to be conducted at selected 
systems. For those contaminants in List 2 and List 3 that do not have 
well developed methods by the time of initial monitoring in 2001, EPA 
would issue a revision to this regulation to activate the contaminants 
at the time when the methods are considered implementable, up to the 
limit of 30 contaminants to be monitored within the five-year 
contaminant listing cycle. Monitoring for those contaminants would then 
begin at a specified effective date in that prospective regulation. 
Therefore, monitoring of contaminants on Lists 2 and 3 would not be 
required by today's proposal and would only occur when EPA publishes a 
revision to this regulation specifying the methods to be used and the 
dates for monitoring to begin, at which time EPA would request public 
comment on the methods. EPA solicits public comment on the selection of 
these contaminants using the CCL priorities for contaminants needing 
occurrence data before regulatory determination and the activation for 
monitoring based on methods availability.
    EPA believes that the CCL process already uses the best available 
information on contaminants of concern and emerging contaminants that 
may need regulation. SDWA section 1445 (a)(2)(B)(ii) provides for the 
Governors of seven or more states to petition the Agency to add 
contaminants to the Monitoring List. This petition process allows for 
the flexibility to include contaminants that are emerging as concerns 
between the five-year listing cycles. EPA, however, does request public 
comment on other criteria that the Agency may use to include 
contaminants of concern on the UCM List that are not on the CCL and may 
not be identified through a Governors' Petition, such as Polonium-210, 
noted above.
(c) Analytical Methods Applicable to the Monitoring List
    The Monitoring List is developed around the availability to 
analytical methods for the listed contaminants and the level of 
information available for them at this time. The discussion below 
highlights analytical methods considerations in listing the 
contaminants for monitoring. Only the contaminants identified on List 1 
will be monitored as a result of today's proposal. Contaminants on 
Lists 2 and 3 below are proposed for the Unregulated Contaminant 
Monitoring List, but will not be activated for monitoring until EPA 
believes that the analytical methods can be applied to obtain reliable 
results. At that time, EPA will propose List 2 and 3 contaminants for 
monitoring.
(i) Chemical Analytical Methods
    The ability to correctly identify a chemical contaminant is 
directly related to the type of chemical and the analytical method 
used. Compounds such as disinfection byproducts are far less likely to 
be misidentified than pesticides because they are typically present at 
relatively high concentrations in disinfected waters, while pesticides 
are much less likely to occur, or occur at lower concentrations. The 
analytical method selected will determine the accuracy of the 
qualitative identification. In general, the most reliable qualitative 
identifications will come from methods that use mass spectral data for 
contaminant identification. However, these methods are typically less 
sensitive than methods that rely on less selective detectors.
    Before EPA establishes a Maximum Contaminant Level (MCL), the 
Agency relies on a analytical method suitable for routine monitoring. 
It is likely that analytical methods in general use by laboratories 
performing drinking water analyses may not exist for some of the 
compounds proposed to be measured in the UCMR program. Complex 
analytical methods or methods requiring special handling often require 
more experienced laboratories than the laboratories performing routine 
compliance monitoring. Even when analytical methods that are in general 
use by analytical laboratories are available, limiting the analyses to 
a small number of laboratories operating under strict quality control 
requirements improves the precision and accuracy of the analyses, 
thereby increasing the usefulness of the data.
    The option favored by many stakeholders and proposed today by EPA 
for conducting the chemical laboratory analyses is the following:
    For PWSs serving more than 10,000 people, the PWS would be 
responsible for sample collection and analyses for unregulated 
contaminant Assessment Monitoring. This monitoring could be conducted 
at the same time as the required compliance monitoring. For unregulated 
contaminant Assessment Monitoring, however, EPA is proposing in 
Sec. 141.40(a)(3) to require quality control procedures for both 
sampling and testing to ensure that the data collected under this 
regulation are of sufficient quality to meet the requirements of the 
related regulatory decisions. Thus, today's proposal specifies the 
analytical methods and procedures to be used in obtaining these data. 
The sampling and associated quality control requirements cover time 
frame, frequency, sample collection and submission, and review and 
reporting of results. The laboratory testing quality control 
requirements address use of a certified laboratory, sample collection/
preservation, analytical methods, method detection limit, calibration, 
quality control sample, method performance test, detection 
confirmation, and reporting.
    The purpose for these quality control requirements is to ensure 
that since EPA will only be able to obtain results from 3,574 systems 
(2,774 large systems and a representative sample of 800 systems from 
65,600 systems serving 10,000 or fewer persons), the Agency obtains the 
most reliable data possible. EPA will provide a guidance manual to 
further explain these quality control measures that would need to be 
performed for all unregulated contaminant monitoring. For systems that 
are part of State Plans for representative samples, the sampling 
guidance, ``UCMR Guidance for Operators of Public Water Systems

[[Page 23405]]

Serving 10,000 or Fewer Persons'' is available. Drafts of the guidance 
and manual ``UCMR Analytical Methods and Quality Control Manual'' are 
available for public comment with this proposed rule through the EPA 
Safe Drinking Water Hotline at 800-426-4791, or through EPA's Office of 
Ground Water and Drinking Water Homepage at www.epa.gov/ogwdw. EPA 
would apply these same testing and quality control procedures to the 
samples of all monitored systems. These proposed procedures are 
discussed in more detail in section 5, Monitoring Requirements under 
the Proposed UCMR.
    EPA is specifying the use of certain analytical methods that are 
currently available for UCM (see Table 5, Unregulated Contaminant 
Monitoring List, III A.2(a) column 3). While these methods are 
routinely used by commercial and public water system laboratories 
(including some that are currently used for compliance monitoring), 
they have not been routinely used for the contaminants on the UCM List. 
Note that, as shown in Sec. 141.40(a)(3), Table 1, methods other than 
those that EPA has developed may be approved for use but quality 
control procedures must also be followed, as specified in 
Sec. 141.40(a)(4) and (5), and appendix A. EPA is requesting comments 
on the methods which have been specified for the contaminants on the 
UCM List.
    The data quality needs associated with drinking water chemical 
compliance monitoring and the evaluation and use of occurrence data are 
different. The purpose of compliance monitoring is to determine whether 
a compound is present currently in the drinking water above the 
established MCL. However, the purpose of the UCM is to obtain 
occurrence data to support future regulatory decisions. The data 
required to make regulatory decisions must be of high quality. All 
analytical methods are subject to false negatives (not detecting a 
contaminant when it is present), false positives (either incorrectly 
identifying or detecting a contaminant, or introducing a contaminant 
into a sample when it is not present), and errors in the accuracy and 
precision of quantitative results.
    The control of false negatives is important for both compliance and 
occurrence monitoring. However, using analytical methods which 
inherently have fewer false positives or requiring quality control 
elements that control false positives, is more critical in occurrence 
than in compliance monitoring. There are much greater incentives 
inherent in compliance monitoring (e.g., the possibility of enforcement 
actions, the potential need to install expensive treatment systems, 
etc., to confirm that the contaminant detected is indeed present) than 
in occurrence data gathering.
    For occurrence monitoring, the precision of the analyses is more 
critical than in compliance monitoring. Unless the concentration of the 
contaminant closely approaches the MCL, even relatively imprecise data 
can be used to ensure the data user that the compound is not present at 
a concentration above the MCL. However, the usefulness of occurrence 
data is much more dependent upon the precision of the measurement. The 
ability to perform meaningful statistical analysis, e.g., to determine 
the percentage of waters in the United States that have compound X at 
or above the minimum reporting level (MRL), or to determine whether 
compound X occurs more frequently or at higher concentrations in one 
type of water or geographical region of the country, is directly 
dependent on the precision of the data.
    The Agency has evaluated analytical methods developed by both EPA 
and other voluntary consensus standards organizations that publish 
analytical methods, such as Standard Methods and the American Society 
for Testing and Materials. The Agency has not approved analytical 
methods published only in analytical journals or methods that use 
techniques that cannot routinely be used by all drinking water analysis 
laboratories (e.g., acid, base/neutral fractionation, or packed column 
gas chromatography). Because control of ``false negatives'' is 
essential to the quality of the data collected under this proposed 
regulation, documentation of the contaminants' stability under the 
sample and extract holding conditions specified in the analytical 
method were also evaluated.
    For the compounds selected to be included in this regulation, the 
following summary, Table 3, Status of Analytical Methods for Chemical 
Contaminants on the UCM List, presents a brief assessment of methods 
availability for each chemical contaminant. EPA requests public comment 
on this assessment of methods availability.

                Table 3.--Status of Analytical Methods for Chemical Contaminants on the UCM List
----------------------------------------------------------------------------------------------------------------
    List 1--Organic chemical
           contaminant                CAS No.          Analytical Methods            Status of availability
----------------------------------------------------------------------------------------------------------------
2,4-dinitrotoluene..............        121-14-2  EPA 525.2                    Method is adequate for
                                                                                monitoring.
2,6-dinitrotoluene..............        606-20-2  EPA 525.2                    Method is adequate for
                                                                                monitoring.
DCPA mono acid degradates.......        887-54-7  EPA 515.1                    No method is available to measure
                                                  EPA 515.2                     the mono and di acid forms
                                                  D5317-93                      separately. All of the approved
                                                  AOAC 992.32                   methods identify total mono and
                                                                                di acid forms.
DCPA di acid degradates.........       2136-79-0  EPA 515.1                    No method is available to measure
                                                  EPA 515.2                     the mono and di acid forms
                                                  D5317-93                      separately. All of the approved
                                                  AOAC 992.32                   methods identify total mono and
                                                                                di acid forms.
4,4'-DDE........................         72-55-9  EPA 508                      Methods are adequate for
                                                  EPA 508.1                     monitoring.
                                                  EPA 525.2
                                                  D5812-96
                                                  AOAC 990.06
EPTC............................        759-94-4  EPA 507                      Methods are adequate for
                                                  EPA 525.2                     monitoring.
                                                  D5475-93
                                                  AOAC 991.07

[[Page 23406]]

 
Molinate........................       2212-67-1  EPA 507                      Methods are adequate for
                                                  EPA 525.2                     monitoring.
                                                  D5475-93
                                                  AOAC 991.07
MTBE............................       1634-04-4  EPA 524.2                    Methods are adequate for
                                                  D5790-95                      monitoring.
                                                  SM6210D
Nitrobenzene....................         98-95-3  EPA 524.2                    Methods are adequate for
                                                  D5790-95                      monitoring.
                                                  SM6210D
Terbacil........................       5902-51-2  EPA 507                      Methods are adequate for
                                                  EPA 525.2                     monitoring.
                                                  D5475-93
                                                  AOAC 991.07


----------------------------------------------------------------------------------------------------------------
    List 2--Organic chemical                       Availability of analytical
           contaminant                CAS No.               methods                  Status of availability
----------------------------------------------------------------------------------------------------------------
1,2-diphenylhydrazine...........        122-66-7  In development.............  Some methods evaluated but
                                                                                inadequate. Priority for
                                                                                analytical method development.
                                                                                Anticipate that contaminant will
                                                                                be added to EPA Method 525.2.
2,4,6-trichlorophenol...........         88-06-2  In development.............  EPA Method 552 evaluated but
                                                                                subject to false positives from
                                                                                interferences of the derivitized
                                                                                byproduct of the contaminant.
                                                                                Anticipate that contaminant will
                                                                                be included in a new solid phase
                                                                                extraction/GC/MS method
                                                                                currently under development.
2,4-dichlorophenol..............        120-83-2  In development.............  EPA Method 552 evaluated but
                                                                                subject to quantitative
                                                                                uncertainty due to inadequate
                                                                                derivatization of the
                                                                                contaminant. Anticipate that
                                                                                contaminant will be included in
                                                                                a new solid phase extraction/GC/
                                                                                MS method currently under
                                                                                development.
2,4-dinitrophenol...............         51-28-5  In development.............  Some methods evaluated but
                                                                                inadequate. Anticipate that
                                                                                contaminant will be included in
                                                                                a new solid phase extraction/GC/
                                                                                MS method currently under
                                                                                development.
2-methy -phenol.................         95-48-7  In development.............  Some methods evaluated but
                                                                                inadequate. Anticipate that
                                                                                contaminant will be included in
                                                                                a new solid phase extraction/GC/
                                                                                MS method currently under
                                                                                development.
Alachlor ESA and degradation      ..............  To be determined...........  EPA is evaluating which specific
 byproducts of acetanilide                                                      contaminants will be included
 pesticides.                                                                    within this group of compounds.
                                                                                Analytical methods will be
                                                                                determined for the targeted
                                                                                contaminants.
Acetochlor......................      34256-82-1  In development.............  No adequate method available.
                                                                                Anticipate that this compound
                                                                                can be added to the scope of EPA
                                                                                Method 525.2
Diazinon........................        333-41-5  In development.............  Diazinon is listed as an
                                                                                contaminant in several EPA and
                                                                                voluntary consensus standard
                                                                                organization methods but it is
                                                                                subject to rapid aqueous
                                                                                degradation. Preservation
                                                                                research currently being
                                                                                conducted to develop
                                                                                preservation technique that
                                                                                would permit adding this
                                                                                compound to EPA Method 525.2.
Disulfoton......................        298-04-4  In development.............  Disulfoton is listed as an
                                                                                contaminant in several EPA and
                                                                                voluntary consensus standard
                                                                                organization methods but it is
                                                                                subject to rapid aqueous
                                                                                degradation. Preservation
                                                                                research currently be conducted
                                                                                to develop preservation
                                                                                technique that would permit
                                                                                adding this compound to EPA
                                                                                Method 525.2.
Diuron..........................        330-54-1  In development.............  While this compound is included
                                                                                in the scope of NPS Method 4
                                                                                (LLE/HLPC/UV) and EPA Method
                                                                                553(SPE/HPLC/MS), these methods
                                                                                are not adequate for this
                                                                                monitoring. Anticipate that this
                                                                                compound can be included in a
                                                                                new SPE/HPLC/UV method currently
                                                                                being developed.
Fonofos.........................        944-22-9  In development.............  Fonofos is listed as an
                                                                                contaminant in several EPA and
                                                                                voluntary consensus standard
                                                                                organization methods but it is
                                                                                subject to rapid aqueous
                                                                                degradation. Preservation
                                                                                research is currently being
                                                                                conducted to develop
                                                                                preservation technique that
                                                                                would permit adding this
                                                                                compound to EPA Method 525.2.
Linuron.........................        330-55-2  In development.............  While this compound is included
                                                                                in the scope of NPS Method 4
                                                                                (LLE/HLPC/UV) and EPA Method
                                                                                553(SPE/HPLC/MS), these methods
                                                                                are not adequate for this
                                                                                monitoring. Anticipate that this
                                                                                compound can be included in a
                                                                                new SPE/HPLC/UV method currently
                                                                                being developed.
Prometon........................       1610-18-0  In development.............  Prometon is listed as an
                                                                                contaminant in several EPA and
                                                                                voluntary consensus standard
                                                                                organization methods but it is
                                                                                subject to rapid aqueous
                                                                                degradation in non-acidified
                                                                                samples and is not readily
                                                                                extracted in acidified samples.
                                                                                Preservation research is
                                                                                currently being conducted to add
                                                                                neutralizing the pH of acidified
                                                                                samples just prior to
                                                                                extraction. This would permit
                                                                                adding this compound to EPA
                                                                                Method 525.2.

[[Page 23407]]

 
Terbufos........................      13071-79-9  In development.............  Terbufos is listed as an
                                                                                contaminant in several EPA and
                                                                                voluntary consensus standard
                                                                                organization methods but it is
                                                                                subject to rapid aqueous
                                                                                degradation. Preservation
                                                                                research is currently being
                                                                                conducted to develop a
                                                                                preservation technique that
                                                                                would permit adding this
                                                                                compound to EPA Method 525.2.
----------------------------------------------------------------------------------------------------------------

(ii) Microbiological Analytical Methods
    The discussion of data quality for chemical analytical methods will 
also apply to microbiological testing when analytical methods are 
developed for CCL microorganisms. When microorganisms were proposed for 
the CCL, EPA recognized that analytical methods were not well developed 
for the majority of them. Because of the lack of available analytical 
methods, some of the CCL microorganisms were grouped either into one 
category where sufficient information was available about methodologies 
to consider regulating them, or another category where more research, 
including research on detection methods and occurrence, was needed. At 
the present time, Aeromonas is the only one of these microorganisms for 
which more occurrence data are needed that also has an analytical 
method that is likely to be sufficiently developed for monitoring in 
time for implementation in the first round of Assessment Monitoring, 
List 1, under this proposed program. Three other microorganisms have 
methods available, but EPA is presently refining these methods. These 
microorganisms may be candidates for the Screening Survey if methods 
development proceeds expeditiously (Sec. 141.40(a)(3), Table 1, List 
2), but are currently identified for Pre-Screen Testing (Table 1, List 
3). The remaining four microorganisms currently lack satisfactory 
methods and will be evaluated for Pre-Screen Testing.
    Several microorganisms on the CCL are actually groups of 
microorganism taxa. In some cases, the taxa have so many members that, 
given the limited resources available for UCMR monitoring, EPA may have 
to prioritize which strains, species, or serotypes are the most 
important to consider and target for monitoring or further study. 
Decisions will have to be made on the basis of health risk, 
disinfection resistance, occurrence in water, and other factors. To 
address the need to prioritize which microorganisms should be targeted 
for monitoring, EPA's Office of Research and Development is assisting 
the Office of Ground Water and Drinking Water in establishing a 
research program for health effects, treatment and analytical methods. 
EPA is requesting public comment on the assessment of methods 
availability and related issues presented below in Table 4.

                                 Table 4.--Status of Analytical Methods for Microbiological Contaminants on the UCM List
--------------------------------------------------------------------------------------------------------------------------------------------------------
           List 1--Microbiological contaminant                        Availability of analytical method                    Status of availability
--------------------------------------------------------------------------------------------------------------------------------------------------------
Aeromonas hydrophila.....................................  Analytical method likely to be available for monitoring  Current modification and evaluation
                                                                                                                     of a published membrane filtration
                                                                                                                     method (Havelaar et al., 1987)
                                                                                                                     indicates that this method will be
                                                                                                                     suitable for the monitoring
                                                                                                                     program.
 
           List 3--Microbiological contaminant
 
Cyanobacteria (blue-green algae, other freshwater algae    Methods available but not standardized.................  Methods are available for counting
 and their toxins).                                                                                                  cyanobacteria but new, standardized
                                                                                                                     methods are needed for direct
                                                                                                                     counts of targeted species with
                                                                                                                     filtration methods or a counting
                                                                                                                     chamber. Standardized analytical
                                                                                                                     methods are also needed to detect
                                                                                                                     the more important cyanobacterial
                                                                                                                     toxins.
Echoviruses..............................................  Methods available but not standardized.................  With care to control overgrowths,
                                                                                                                     echoviruses can be cultured on BGM
                                                                                                                     cells and detected by ICR method
                                                                                                                     but need methods such as
                                                                                                                     serological typing to distinguish
                                                                                                                     from other viruses. Cost of cell
                                                                                                                     culture assays plus serotyping can
                                                                                                                     be high. PCR methods, which are not
                                                                                                                     available, are subject to
                                                                                                                     interferences and do not
                                                                                                                     demonstrate infectivity.
Coxsackieviruses.........................................  Methods available but not standardized.................  Group B coxsackieviruses are easy to
                                                                                                                     grow in tissue culture but group A
                                                                                                                     coxsackieviruses are variable.
                                                                                                                     Culturable coxsackieviruses can be
                                                                                                                     detected with the ICR method but
                                                                                                                     serotyping is needed to distinguish
                                                                                                                     coxsackie from other viruses. Other
                                                                                                                     detection methods such as
                                                                                                                     immunoassay or PCR do not exist.
                                                                                                                     New, standardized methods are
                                                                                                                     needed.
Helicobacter pylori......................................  No method currently available..........................  Helicobacter pylori is difficult to
                                                                                                                     grow due to slow growth and the
                                                                                                                     need for a low oxygen environment.
                                                                                                                     No selective medium exist that will
                                                                                                                     discriminate H. pylori from
                                                                                                                     background bacteria. A culturable
                                                                                                                     method that demonstrates viability
                                                                                                                     is preferred. Methods are needed
                                                                                                                     for selective growth and
                                                                                                                     identification. IMS has been used
                                                                                                                     to concentrate Helicobacter pylori.
                                                                                                                     PCR methods have been used but are
                                                                                                                     not preferred due to interferences
                                                                                                                     and the inability to demonstrate
                                                                                                                     viability.

[[Page 23408]]

 
Microsporidia............................................  No method currently available..........................  No methods are available for the
                                                                                                                     monitoring of the two species of
                                                                                                                     human microspordia which have a
                                                                                                                     waterborne route of transmission
                                                                                                                     (Enterocytozoon bienuesi and
                                                                                                                     Septata intestinalis). Oocysts
                                                                                                                     could possibly be detected by
                                                                                                                     methods similar to those being
                                                                                                                     developed for Cryptosporidium.
                                                                                                                     Potential methods may utilize water
                                                                                                                     filtration, clean-up with
                                                                                                                     immunomagnetic separation (IMS) and
                                                                                                                     detection using microscopy with
                                                                                                                     either fluorescent antibody or gene
                                                                                                                     probe procedures. Due to the small
                                                                                                                     size of microsporidia, problems
                                                                                                                     could be encountered during
                                                                                                                     filtration.
Adenoviruses.............................................  No method currently available..........................  Adenoviruses serotypes 1 to 39 can
                                                                                                                     be grown in tissue culture but
                                                                                                                     enteric adenoviruses 40 to 41 are
                                                                                                                     difficult to grow. Several
                                                                                                                     selective tissue culture methods
                                                                                                                     and detection methods have been
                                                                                                                     reported. A selective, standardized
                                                                                                                     method is needed for monitoring.
                                                                                                                     PCR methods are not preferred
                                                                                                                     because of interferences and
                                                                                                                     inability to demonstrate
                                                                                                                     infectivity.
Caliciviruses............................................  No method currently available..........................  No tissue culture methods exist for
                                                                                                                     the two caliciviruses on the CCL
                                                                                                                     (Norwalk and Snow Mountain). No
                                                                                                                     sensitive or fully developed
                                                                                                                     detection methods exist. PCR
                                                                                                                     methods are not preferred due to
                                                                                                                     interferences and the inability to
                                                                                                                     demonstrate infectivity.
--------------------------------------------------------------------------------------------------------------------------------------------------------

(d) Screening Methods
    SDWA section 1445(i) requires EPA to review new analytical methods 
that may be used for regulated contaminants screening and analysis. 
After this review, EPA may approve such methods that are deemed ``more 
accurate or cost-effective than established reference methods for use 
in compliance monitoring.'' Section 1445(a)(2)(G) also allows States to 
use screening methods approved by the Administrator for unregulated 
contaminant monitoring. These methods are expected to provide 
flexibility in compliance monitoring to water systems and laboratories 
performing analysis on behalf on these systems. They are expected to be 
``better and/or faster'' than existing analytical methods. EPA is 
developing a framework for the use of screening procedures for 
monitoring drinking water contaminants, and determining how the Agency 
will approve or recommend screening procedures for specific 
contaminants.
2. List of Contaminants To Be Monitored
(a) Proposed Monitoring List
    Table 5, Unregulated Contaminant Monitoring List (Proposed), 
presents EPA's proposal for the initial list of unregulated 
contaminants for monitoring under section 1445(a)(2)(B)(i). The 
monitoring program that EPA proposes for these contaminants is a three-
tiered approach based on the availability of information about each 
contaminant and the availability of analytical methods for each 
contaminant. This approach is described in section C., Type of 
Monitoring Required of Public Water Systems Based on Listing Group. The 
proposed monitoring program divides the listed unregulated contaminants 
into three lists: List 1, for which Assessment Monitoring will be 
required, List 2, designated for the Screening Survey; and List 3, 
designated for Pre-screen Testing. Today's proposed regulation only 
requires Assessment Monitoring for List 1 contaminants beginning on the 
proposed effective date of January 1, 2001. The monitoring for 
contaminants on Lists 2 and 3 will only be required after EPA 
promulgates further rules.
    EPA proposes requiring Assessment Monitoring for those contaminants 
for which methods exist at the time this regulation is promulgated; as 
a result, some contaminants from List 2 may move to List 1 if EPA 
considers their methods reliable by promulgation of the final 
regulation. Also, by future rulemaking, EPA plans to implement the 
Screening Survey (List 2) monitoring in groups or batches of 
contaminants, rather than one contaminant at a time, to minimize 
sampling and testing costs since some of the contaminants may be tested 
by the same method. EPA proposes to take a similar approach with the 
contaminants in the Pre-Screen Testing (List 3) category. EPA plans to 
require, through future rulemaking Pre-Screen Testing for contaminants 
for which EPA needs to determine that new analytical methods can 
measure their existence in locations most likely to be found. All 
analytical methods for contaminants on Lists 2 and 3 would be peer 
reviewed, following EPA's policy for peer review, before the Agency 
proposes regulations which would require public water systems to 
monitor for them. EPA is seeking comment on the approach of a three-
tiered monitoring program for unregulated contaminants and on the 
proposed list of contaminants to be monitored.
    In Table 5, List 1 contaminants, for Assessment Monitoring, are 
organic chemicals and one microbiological contaminant for which 
analytical methods capable of generating the quantity and quality of 
data required under the UCMR are currently available, or expected to be 
available by promulgation of the final rule (August 1999). Monitoring 
for these contaminants would be required under today's proposed UCMR. 
These contaminants are in today's proposed rule, Sec. 141.40(a)(3), 
Table 1, Unregulated Contaminant Monitoring List, List 1.
    List 2 contaminants (all organic chemicals, at this time), 
contaminants for the Screening Survey, are those for which EPA is 
currently refining analytical methods. Development of these methods 
should be sufficient for a Screening Survey to be conducted in the 
first three years of the listing cycle, but may occur in the later 
years of the cycle. If methods are available for any of these 
contaminants before promulgation of the final rule, they will be added 
to Assessment Monitoring, List 1. These contaminants are characterized 
in today's proposed rule at Table 1, Unregulated Contaminant Monitoring 
List, List 2.
    List 3 contaminants (all microbiological contaminants, at this 
time), contaminants for Pre-screen Testing, are those for which EPA has 
begun or shortly will begin analytical methods development, but 
completion of those efforts is not expected prior to the Assessment 
Monitoring or Screening Survey required under implementation

[[Page 23409]]

of this regulation. Instead, these contaminants would be tested for in 
Pre-Screen Testing. These contaminants are in today's proposed rule at 
Sec. 141.40(a)(3) as Table 1, Unregulated Contaminant Monitoring List, 
List 3.
    The column headings of Table 5 include:

1--Chemical or microbiological contaminant: the name of the 
contaminants to be analyzed.
2--CAS No. (Chemical Abstract Service Number): a unique number 
identifying the chemical contaminants.
3--Analytical Methods: method numbers identifying the methods that 
could be used to test the contaminants.
4--Minimum Reporting Level: the value and unit of measure at or above 
which the concentration or density of the contaminant must be measured 
using the Approved Analytical Methods.
5--Sampling Location: the locations within a PWS at which samples must 
be collected.
6--Date Monitoring to Begin: The years during which the sampling and 
testing are to occur for the indicated contaminant.

                                              Table 5.--Unregulated Contaminant Monitoring List (Proposed)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                     2--CAS                                                                                                 6--Date
        1--Contaminant           identification       3--Analytical methods         4--Minimum reporting       5--Sampling location      monitoring to
                                      No.                                                  level                                             begin
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                              List 1--Assessment Monitoring: Organic Chemical Contaminants
--------------------------------------------------------------------------------------------------------------------------------------------------------
2,4-dinitrotoluene...........           121-14-2  EPA 525.2 a                    2.4 ug/L e                 EPTDS f                            2001-2003
2,6-dinitrotoluene...........           606-20-2  EPA 525.2 a                    2.0 ug/L e                 EPTDS f                            2001-2003
DCPA mono acid degradate.....           887-54-7  EPA 515.1 a                    1.0 ug/L e                 EPTDS f                            2001-2003
                                                  EPA 515.2 a
                                                  5317-93 b
                                                  AOAC 992.32 c
DCPA di acid degradate.......          2136-79-0  EPA 515.1 a                    1.0 ug/Le                  EPTDS f                            2001-2003
                                                  EPA 515.2 a
                                                  D5317-93 b
                                                  AOAC 992.32 c
4,4'-DDE.....................            72-55-9  EPA 508 a                      0.75 ug/Le                 EPTDS f                            2001-2003
                                                  EPA 508.1 a
                                                  EPA 525.2 a
                                                  D5812-96 b
EPTC.........................           759-94-4  EPA 507 a                      1.2 ug/L e                 EPTDS f                            2001-2003
Molinate.....................          2212-67-1  EPA 507 a                      0.87 ug/L e                EPTDS f                            2001-2003
                                                  EPA 525.2 a
                                                  D5475-93 b
                                                  AOAC 991.07 c
MTBE.........................          1634-04-4  EPA 524.2 a                    5.0 ug/L g                 EPTDS f                            2001-2003
                                                  5790-95 b
                                                  SM6210D d
Nitrobenzene.................            98-95-3  EPA 524.2 a                    12 ug/L g                  EPTDS f                            2001-2003
                                                  D5790-95 b
                                                  SM6210D d
Terbacil.....................          5902-51-2  EPA 507 a                      23 ug/Le                   EPTDS f                            2001-2003
                                                  EPA 525.2 a
                                                  5475-93 b
                                                  AOAC 991.07 c
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                               List 1--Assessment Monitoring: Microbiological Contaminants
--------------------------------------------------------------------------------------------------------------------------------------------------------
Aeromonas Hydrophila.........         Reserved h  Membrane filter, in review     1 colony forming unit      (1) Near end of                    2001-2003
                                                                                                             distribution line with
                                                                                                             longest residence time;
                                                                                                             (2) at a representative
                                                                                                             site in the distribution
                                                                                                             system


--------------------------------------------------------------------------------------------------------------------------------------------------------
                                           CAS
       Chemical contaminant           identification     Anticipated analytical methods         Minimum reporting level e          Sampling location
                                           No.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                 List 2--Screening Survey: Organic Chemical Contaminants (To Be Sampled After Notice of Analytical Methods Availability)
--------------------------------------------------------------------------------------------------------------------------------------------------------
1,2-diphenylhydrazine.............           122-66-7  EPA 525.2 i                         TBD h                               EPTDS f
2-methyl-phenol...................            95-48-7  SPE/GC/MS l                         TBD h                               EPTDS f
2,4-dichlorophenol................           120-83-2  SPE/GC/MS l                         TBD h                               EPTDS f
2,4-dinitrophenol.................            51-28-5  SPE/GC/MS l                         TBD h                               EPTDS f
2,4,6-trichlorophenol.............            88-06-2  SPE/GC/MS l                         TBD h                               EPTDS f
Acetochlor........................         34256-82-1  EPA 525.2 i                         TBD h                               EPTDS f
Alachlor ESA......................  .................  TBD h                               TBD h                               EPTDS f
Diazinon..........................           333-41-5  EPA 525.2 k                         TBD h                               EPTDS f
                                                                                           TBD h                               EPTDS f
Disulfoton........................           298-04-4  EPA 525.2 k                         ..................................  .........................

[[Page 23410]]

 
Diuron............................           330-54-1  SPE/HPLC/UV j                       TBD h                               EPTDS f
                                                                                           TBD h                               EPTDS f
Fonofos...........................           944-22-9  EPA 525.2 i                         ..................................  .........................
Linuron...........................           330-55-2  SPE/HPLC/UV j                       TBD h                               EPTDS f
Prometon..........................          1610-18-0  EPA 525.2 k                         TBD h                               EPTDS f
                                                                                           TBD h                               EPTDS f
Terbufos..........................         13071-79-9  EPA 525.2 k                         ..................................  .........................
--------------------------------------------------------------------------------------------------------------------------------------------------------
a The version of the EPA methods being approved will be dependent upon the status of the approval of new versions for compliance monitoring. If
  appropriate regulations approving new versions of EPA compliance monitoring methods are completed prior to the promulgation of this regulation, the
  following versions of the above methods will be approved. Methods for the Determination of Organic Compounds in Drinking Water--Supplement III, EPA-
  600/R-95-131, August 1995. NTIS PB95-261616. Copies are also available from the National Technical Information Service (NTIS), U.S. Department of
  Commerce, 5285 Port Royal Road, Springfield, Virginia 22161. The toll-free number is 800-553-6847.
If new regulations changing the versions of methods being approved for compliance monitoring are not completed prior to the promulgation of this
  regulation, then the following versions of the EPA methods are being approved for monitoring under the Unregulated Contaminant Monitoring Rule.
  Methods 507, 508, and 515.1 are in Methods for the Determination of Organic Compounds in Drinking Water, EPA-600/4-88-039, December 1988, Revised,
  July 1991. Methods 515.2 and 524.2 are in Methods for the Determination of Organic Compounds in Drinking Water--Supplement II, EPA/600/R-92/129,
  August 1992. These documents are available from the National Technical Information Service, (NTIS) U.S. Department of Commerce, 5285 Port Royal Road,
  Springfield, Virginia 22161 (800) 553-6847. Methods 508.1 and 525.2 are available from US EPA NERL--Cincinnati, Cincinnati, Ohio 45268, (513) 569-
  7586.
b Annual Book of ASTM Standards, 1996 and 1998, Vol. 11.02, American Society for Testing and Materials. Method D5812-96 is located in the Annual Book of
  ASTM Standards, 1998, Vol. 11.02. Methods D5790-95, D5475-93, and D5317-93 are located in the Annual Book of ASTM Standards, 1996 and 1998, Vol 11.02.
  Copies may be obtained from the American Society for Testing and Materials, 101 Barr Harbor Drive, West Conshohocken, PA 19428.
c Official Methods of Analysis of AOAC (Association of Official Analytical Chemist) International, Sixteenth Edition, 4th Revision, 1998, Volume I, AOAC
  International, First Union National Bank Lockbox, PO Box 75198, Baltimore, MD 21275-5198. 1-800-379-2622.
d 18th and 19th editions of Standard Methods for the Examination of Water and Wastewater, 1992 and 1995, American Public Health Association; either
  edition may be used. Copies may be obtained from the American Public Health Association, 1015 Fifteenth Street NW, Washington, DC 20005.
e Minimum Reporting Level determined by multiplying by 10 the least sensitive method's minimum detection limit (MDL=standard deviation times the
  Student's T value for 99% confidence level with n-1 degrees of freedom), or when available, multiplying by 5 the least sensitive method's estimated
  detection limit (where the EDL equals the concentration of compound yielding approximately a 5 to 1 signal to noise ratio or the calculated MDL,
  whichever is greater).
f Entry Points to the Distribution System, After Treatment.
g Minimum Reporting Levels (MRL) for Volatile Organic Compounds (VOC) determined by multiplying either the published Method Detection Limit (MDL) or 0.5
  g/L times 10, whichever is greater. The MDL of 0.5 ug/L (0.0005 mg/L) was selected to conform to VOC MDL requirements of 40 CFR
  141.24(f)(17(E).
h To be Determined.
i Compound currently not listed as a contaminant in this method. Methods development currently being conducted in an attempt to add it to the scope of
  this method.
j Methods development currently in progress to develop a solid phase extraction/high performance liquid chromatography/ultraviolet method for the
  determination of this compound.
k Compound listed as being a contaminant using EPA Method 525.2; however, adequate sample preservation is not available. Preservation studies currently
  being conducted to develop adequate sample preservation.
l Methods development currently in progress to develop a solid phase extraction/gas chromatography/mass spectrometery method for the determination of
  this compound.


--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                  Anticipated sampling
          Microorganism              Identification No.      Anticipated analytical methods        Minimum reporting level              location
--------------------------------------------------------------------------------------------------------------------------------------------------------
             List 3--Pre-screen Testing: Contaminants With Analytical Methods Not Anticipated (To Be Available by Regulation Implementation)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Cyanobacteria (blue-green algae,  Reserved a..............  TBD a                             TBD a                             TBD a
 other freshwater algae and
 their toxins).
Echoviruses.....................  Reserved a..............  TBD a                             TBD a                             TBD a
Coxsackieviruses................  Reserved a..............  TBD a                             TBD a                             TBD a
Helicobacter pylori.............  Reserved a..............  TBD a                             TBD a                             TBD a
Microsporidia...................  Reserved a..............  TBD a                             TBD a                             TBD a
Caliciviruses...................  Reserved a..............  TBD a                             TBD a                             TBD a
Adenoviruses....................  Reserved a..............  TBD a                             TBD a                             TBD a
--------------------------------------------------------------------------------------------------------------------------------------------------------
a=To Be Determined.

    Tables 3 and 4, in III.A.1.(c), Analytical Methods Applicable to 
the Monitoring List, present a summary of the status of the methods for 
all the contaminants on this list.
    EPA believes that this three-tiered approach to the Monitoring List 
and program, which was recommended by stakeholders, reflects a balance 
between the implementability of current analytical methods and the need 
to obtain data in time frames that are useful for responding to 
concerns about the contaminants identified.
(b) Number of Contaminants on the Monitoring List
    Thirty-two contaminants are on the UCM List, as proposed. SDWA 
Section 1445 (a)(2)(B)(i) indicates that the List shall not have more 
than 30 contaminants required to be monitored by public water systems. 
EPA interprets this to mean that the List may contain more than 30 
contaminants, as long as monitoring is not required for more than 30 
contaminants during the five-year listing cycle. EPA proposes that the 
32 contaminants identified in the CCL Occurrence Priorities remain on 
the UCM List, with monitoring required for no more than 30 contaminants 
in any five-year UCM cycle. Furthermore, EPA proposes that future UCM 
Lists may include additional contaminants beyond 30, but the UCMR 
Program would only

[[Page 23411]]

require monitoring for up to 30 contaminants during any listing cycle.
    The contaminants beyond 30 are ones for which PWSs might 
voluntarily provide data if they monitored for them for their own 
purposes. These additionally identified contaminants might also be ones 
for which PWSs might send EPA samples to be tested and analyzed (by 
EPA) if the Agency is developing or recently developed a provisional 
analytical method for them. EPA is preparing a guidance document 
specifying the procedures for voluntary submission of such data in the 
future to the National Contaminant Occurrence Database (NCOD). EPA 
requests public comment on maintaining a UCM List of more than 30 
contaminants, but limiting PWS monitoring to 30 contaminants in any 
five-year UCMR listing cycle.
(c) Modifying the Monitoring List through the Governors' Petition
    Section 1445(a)(2)(B)(ii) of SDWA provides that the Administrator 
shall include in the UCM List each contaminant recommended in a 
petition signed by the Governor of each of seven or more States, unless 
the Administrator determines that the action would prevent the listing 
of contaminants of a higher public health concern.
    The statutory provision acknowledges the roles of States in setting 
priorities for developing health-based drinking water standards. The 
Governors' petition also provides a formal mechanism for addressing 
drinking water contaminants of concern that are identified between the 
periodic updating of the Unregulated Contaminant Monitoring Rule and 
the parallel five-year cycle of the Contaminant Candidate List.
(i) Circumstances Affecting the Governors' Petition
    Given the requirement that the petition be signed by seven 
Governors, the petition process is likely to be used only when a 
contaminant has been identified in drinking water or sources of 
drinking water that appear to necessitate prompt action to determine 
its extent of occurrence. Under EPA's present approach to preparing the 
Contaminant Candidate List, with States and other stakeholders 
providing input for setting health-based priorities for research and 
standard-setting, contaminants of concern are likely to be addressed, 
at least initially, by special studies to determine the significance of 
their occurrence. One example of an emerging contaminant would be 
methyl tert butyl ether (MTBE). EPA is working with the U.S. Geological 
Survey to collect information on the occurrence of MTBE in northeastern 
States. Perchlorate is another example of an emerging contaminant of 
concern; the CCL notes that occurrence information is needed and will 
likely be obtained through special studies. California is studying 
perchlorate occurrence by requesting all water utilities with 
vulnerable sources to monitor for it and other States are also 
monitoring for this contaminant.
    Given the necessary resources, EPA expects that well-designed 
studies will, in many cases, more expeditiously determine the 
significance of a critical new contaminant's occurrence than the 
regulatory process of requiring monitoring through the UCMR. However, 
today's proposal includes a codification of this statutory petition 
process.
(ii) Response to Governors' Petition
    EPA proposes the following approach to contaminants contained in a 
Governors' petition. If the UCMR List contains fewer than 30 
contaminants, the Administrator would add the recommended 
contaminant(s) to the UMCR list as expeditiously as the regulatory 
process and the availability of (an) acceptable analytical method(s) 
allow. Representative monitoring of small systems, however, could be 
delayed if EPA is devoting all the resources authorized by statute or 
appropriated to UCMR Assessment Monitoring and Screening Survey, and 
the monitoring of the State-recommended contaminant(s) would prevent 
monitoring of other contaminants of a higher health concern by directly 
replacing them or by making the collection and testing of the remaining 
contaminants more difficult to conduct, adding costs not anticipated. 
The other possibility is to conduct Pre-Screen Testing for the 
contaminant if a method was at the stage of development to allow its 
application in a highly controlled laboratory setting. This testing 
would focus on PWSs that might be more likely locations for the 
contaminant to occur.
    If the UCMR list is at the statutory maximum of 30 contaminants for 
which monitoring is required, the Administrator must determine whether 
a State-recommended contaminant is of a higher public health concern 
than one of the contaminants already on the list. The ideal approach 
would be to compare the contaminant's occurrence weighted by the degree 
to which populations are exposed to levels above a health-based 
criterion. Although not required, the Governors' petition would likely 
cite State and/or other evidence of widespread contamination or 
potential for contamination. Health effects information may be minimal, 
particularly for probable drinking water exposures. In such a case, the 
Administrator would need to compare all the information available on 
the State-recommended contaminant(s) related to public health concerns, 
including special concerns for children and other sensitive 
subpopulations, and the availability of analytical methods to that of 
the contaminants on the UCMR list, to determine which, if any, 
contaminant(s) on the list of contaminants for which monitoring is 
required it/they should replace.

B. Public Water Systems Subject to the UCMR

    The monitoring in these proposed revisions focuses ultimately on 
determining, on a national basis, the occurrence or likely occurrence 
of contaminants in drinking water of community water systems (CWS) and 
non-transient non-community water systems (NTNCWS). For regulatory 
purposes, public water systems are categorized as ``community water 
systems,'' or ``non-community water systems.'' Community water systems 
are specifically defined as ``public water systems which serve at least 
15 service connections used by year-round residents or regularly serve 
at least 25 year-round residents.'' (40 CFR 141.2) A ``non-community 
water system'' means any other public water system. Non-community water 
systems include nontranisent non-community water systems and transient 
non-community water systems. Non-community water systems are available 
to serve the public, but are not used on a year-round basis in most 
cases. Non-transient systems regular serve at least 25 of the same 
persons over six months per year (e.g., schools). Transient systems do 
not regularly serve at least 25 of the same persons over six months per 
year.
    One of the factors to be considered in establishing the revised UCM 
program under the 1996 SDWA Amendments is the number of persons served 
by a system. With respect to size, about 2,774 large systems (each 
serving more than 10,000 persons) provide drinking water to about 80 
percent of the U.S. population served by public water systems. Under 
today's proposed regulation, all large systems would be required to 
monitor the unregulated contaminants specified in Sec. 141.40(a)(3).
    Section 1445(a)(2)(A) requires that the UCMR ensure that only a 
representative sample of systems serving 10,000 or fewer persons be 
required to monitor unregulated contaminants. The small community water 
systems, each serving

[[Page 23412]]

10,000 or fewer persons, and the non-transient, non-community water 
systems total 65,636 systems. EPA proposes that these systems be the 
set from which the national representative sample of systems is 
selected. EPA proposes that transient non-community systems be excluded 
from unregulated contaminant monitoring requirements. The variation in 
the 97,000 transient systems would be difficult to reflect in a 
national representative sample and could be very costly. Furthermore, 
projecting contaminant exposure results from such systems would be 
complex and inconclusive because of the transient nature of the 
population that uses them. The results from the very small community 
and non-transient, non-community systems (NTNCWS) could be extrapolated 
to these systems.
    EPA will pay for the reasonable costs of monitoring for this 
representative sample, as long as the systems are part of a State 
Monitoring Plan. The Agency proposes that each system be selected 
through the use of a random number generator and monitored according to 
a nationally representative sample plan developed on the basis of 
population served by PWSs in each State. This is necessary to ensure 
the validity of the sample nationally and because EPA typically has the 
least information about these systems and needs a consistent base of 
data for program development. EPA proposes that a national sample of 
approximately 800 systems serving 10,000 or fewer persons would be 
statistically drawn from the national population served by PWSs. 
Section F, ``Representative Sample of Systems Serving 10,000 or Fewer 
Persons,'' provides the basis for this sample size. The number of 
systems selected within each size range of small systems will be based 
on the proportion of the State's population served by that size range 
within water source type. The State-based component of this national 
representative sample, called a State Monitoring Plan (or State Plan), 
would be reviewed and if necessary modified by a State. The resulting 
State Plans would then be part of a national sample framework, 
providing the representative national sample requisite to drawing 
national conclusions.
    Additionally, to provide an improved understanding of contaminants 
and conditions affecting small systems, and additional quality 
assurance for this small sample, EPA proposes to statistically select 
up to 30 small public water systems from the systems in State 
Monitoring Plans using a random number generator as ``index'' sites at 
which contaminants would be monitored for every year during the five 
year listing cycle. EPA would conduct the sampling and testing for 
systems selected as index sites. At the time of sampling, EPA would 
also gather other data to characterize the environmental setting 
affecting the system including precipitation, land and water resource 
use and environmental data (such as soil type and geology).
    Also, up to 150 additional small systems might be selected for the 
Pre-Screen Testing. The systems for the Pre-Screen Testing will be 
selected on the basis of their representativeness of systems most 
vulnerable to the particular List 3 contaminants. The statistical 
selection of the 800 systems for the national representative sample may 
not include the systems deemed most vulnerable to these contaminants, 
hence, the States and EPA may need to select additional systems for 
this targeted testing.

C. Type of Monitoring Required of Public Water Systems Based on Listing 
Group

    At the Unregulated Contaminant Monitoring Regulation Stakeholders 
Meeting on June 3-4, 1998, a range of stakeholders suggested that the 
UCMR monitoring program be developed through a progression of 
monitoring levels based on contaminant groups that reflect current 
information about both the occurrence of the contaminants and method 
development. Current information and methods availability would 
determine the extent of monitoring. Both EPA and stakeholders are 
concerned about contaminants that may be ``emerging'' as contaminants 
of concern because they have not been monitored before but have the 
potential to be found near or in drinking water supplies or have been 
identified as potential health problems. An ``emerging contaminant of 
concern'' would not likely be covered by an approved EPA analytical 
method. Typically, ``research'' methods are used to detect such 
emerging contaminants and may be expensive. EPA would have to either 
develop an approved method for inclusion in a regulatory approach, or 
perhaps substitute a regulatory approach with a study using a single 
laboratory and a ``research'' method. The need to develop an approved 
analytical method would ``compete'' against other contaminants on the 
CCL that also require analytical method development. In recognition of 
these considerations, EPA proposed an approach with three monitoring 
levels, referred to as ``Assessment Monitoring,'' ``Screening Survey,'' 
and ``Pre-screen Testing,'' described below. EPA is seeking public 
comment on this approach.
1. Assessment Monitoring
    The first type of monitoring in the three-tiered monitoring program 
that EPA proposes today pertains to the group of contaminants for which 
analytical methods are specified in Sec. 141.40(a)(3), Table 1, List 1, 
Assessment Monitoring and in today's Preamble in Table 5, List 1. 
Importantly, these contaminants are ones for which initial data for 
PWSs indicate that the contaminants occur in at least two States or ten 
public water systems and should be monitored to assess national 
occurrence through UCM.
    In Sec. 141.40, EPA is proposing that each system conduct UCMR 
``Assessment Monitoring'' of List 1 contaminants for a twelve-month 
period in the first three years of a five year UCMR contaminant listing 
cycle. Large systems would complete this monitoring in any twelve month 
period beginning in the years 2001 to 2003. Small systems in State 
Monitoring Plans would complete the monitoring according to the 
scheduled monitoring identified in those plans within the period of 
2001 to 2003. Section F, ``Representative Sample of Systems Serving 
10,000 or fewer persons,'' describes in detail the subset of small 
systems required to monitor. The State could specify in the State 
Monitoring Plans the schedule that would correlate with compliance 
monitoring. This arrangement should enable systems to complete UCMR 
sampling coincident with their compliance monitoring for regulated 
contaminants during one of the years when compliance monitoring is 
required. However, EPA recognizes that some large systems may not be 
required to monitor for any regulated contaminants to allow compliance 
within the five years after the effective date of this rule. In such a 
case, such large systems could monitor for the unregulated contaminants 
for any twelve-month period with in the five years they choose.
    EPA is proposing that surface water systems monitor for four 
consecutive quarters and ground water systems two times six months 
apart. Under Assessment Monitoring, systems serving more than 10,000 
persons would conduct and pay for their own sample collection and 
testing. Small systems included in State Monitoring Plans would collect 
the samples with EPA-supplied equipment and send the samples to EPA-
specified laboratories. EPA would pay for the testing and reporting. 
The system would still have overall reporting responsibility to the

[[Page 23413]]

primacy agency. Frequency and location of monitoring are discussed in 
section D, ``Monitoring Requirements under the Proposed UCMR.''
2. Screening Survey
    The contaminants that EPA is considering for the Screening Survey 
are listed in Table 5, List 2 and consist of those for which analytical 
methods are under development and for which EPA has less occurrence 
data than for the contaminants on List 1. The purpose of the Screening 
Survey is to analyze for contaminants where the use of newly developed, 
non-routine analytical methods are required. To do this, EPA would 
maximize the quality of the occurrence data obtained by using only a 
select, controlled group of laboratories. In addition, the Screening 
Survey might allow EPA to maximize occurrence data gathering resources 
by having a structure in place that would obtain scientifically 
defensible occurrence data for emerging contaminants of concern, more 
quickly than could be obtained through standard unregulated contaminant 
monitoring efforts. The Screening Survey could, for example, be useful 
where questions concerning whether a contaminant of concern is in fact 
occurring in drinking water. The Screening Survey is also intended to 
allow EPA to screen contaminants to see if they occur frequently enough 
to justify inclusion in future unregulated contaminant Assessment 
Monitoring or so frequently as not to require further monitoring but 
allow the Agency to begin to develop standards.
    The contaminants in List 2 would be tested for in drinking water of 
a smaller, statistically valid sample of all (large and small) 
community and non-transient, noncommunity water systems (for example, 
about 300 systems), selected through a random number generator used to 
identify specific PWSs. The sample size needed for estimating 
frequencies of contaminant occurrence are smaller if the actual 
frequencies are close to 0, or to 100, percent. When a contaminant is 
consistently present, or consistently absent, it requires fewer samples 
to determine its frequency with adequate statistical confidence than if 
it occurs about half the time. Only 300 PWSs are needed to determine if 
a contaminant is present 5 percent or less frequently, at a 99 percent 
confidence level and with a 3 percent margin of error. (The same 
criteria require 1,844 samples when the frequency could be any number.) 
If the contaminant occurrence were over the threshold established for 
the Screening Survey, EPA would include the contaminant in the next 
Assessment Monitoring round (projected to begin in 2006) of the UCM 
program. The statistical threshold for positive results from this 
testing to determine if further testing is warranted might be 1 to 2 
percent of systems having detections. If the contaminant occurrence 
were under the threshold, then no further testing would be required, 
and the contaminant may be removed from the list in a future UCM 
rulemaking. EPA is requesting public comment on whether the statistical 
threshold of 1 to 2 percent of systems is adequate to make a 
determination that further Assessment Monitoring should be conducted to 
determine the extent of contaminant occurrence, and, if not, what 
percent should be used as the threshold for such a determination .
    The analytical methods that might be used are identified in Table 
5, List 2, Screening Survey, as ``Anticipated Analytical Methods.'' 
These methods are being refined for the particular contaminants on List 
2 and are not expected to be ready for use in an Assessment Monitoring 
program. Therefore, as groups of contaminants from List 2 have 
analytical methods that can be applied, EPA will publish a rule 
modification for public comment indicating the analytical methods and 
minimum reporting levels applicable to the contaminants and the 
location and timeframe for sampling.
    Comments on the ``Screening Survey'' should address both the 
rationale for the contaminants identified for the Screening Survey and 
the monitoring program for them. Additionally, EPA is requesting public 
comment on two potential outcomes from the ``Screening Survey'': (1) As 
noted previously, if the contaminant is observed at very few or no PWSs 
(i.e., less than the threshold of 1 to 2 percent of systems), then the 
contaminant would be dropped from the UCM List 2 and no further 
monitoring for it would occur, and (2) if the contaminant is observed 
extensively (i.e., in a higher percentage of PWSs, such as 5 to 10 
percent) and EPA has health effects data on it that indicate a 
significant concern, then it may move directly to the regulation 
development stage. In that case, there may be no Assessment Monitoring 
to provide additional occurrence data for that contaminant, depending 
on the urgency of the situation and existing data sufficiency.
    With respect to funding the Screening Survey, EPA proposes that it 
pay for the testing and reporting (as described in Preamble section 
III.G., Reporting of Monitoring Results) for systems serving 10,000 or 
fewer persons. Systems serving 10,000 or fewer persons would be 
responsible for sample collection and preparing the samples for 
shipment. EPA would pay for the shipment of these samples to an EPA 
designated laboratory for testing.
    For large systems serving more than 10,000 persons, EPA requests 
public comment on which alternative testing approach it would follow: 
(1) The large system would collect the samples, and submit them to a 
laboratory approved for testing List 2 contaminants based on EPA's 
evaluation of the laboratory's capability, blind sample test results, 
experience with similar methods, willingness to test samples from any 
PWS regulated under this regulation, and reasonableness of offered 
service price. The approved laboratory would report the results to the 
system. These large systems would be responsible for paying for the 
costs of testing by the EPA approved laboratory. (2) EPA would specify 
a strict protocol and performance criteria, that must be followed for 
this Screening Survey testing, including possible additional reporting 
requirements to allow comparison of the results with results from EPA's 
laboratory. Large systems could submit data from the test results for 
the List 2 contaminants as long as the laboratory doing the testing 
could document that it followed the protocol. These protocol and 
criteria would need to be published when the EPA publishes the 
rulemaking for public comment that contaminants in List 2 have methods 
ready for use in the UCMR program. EPA's concerns about this 
alternative testing approach are: (1) Increasing the number of 
laboratories participating would adversely impact the precision of the 
resulting data therefore, requiring a substantial increase in the 
number of utilities sampled to compensate, (2) A laboratory 
certification system would need to be established, causing considerable 
additional burden for both the States and EPA, and (3) no common 
analytical standards are available. EPA requests public comment on 
whether other options exist that would have low administrative burden 
for the States and EPA, have reasonable costs for testing List 2 
contaminants by large systems, and allow EPA to obtain the scientific 
and defensible data it needs to make regulatory decisions.
    EPA believes that one of these two arrangements for conducting the 
Screening Survey monitoring at large systems is necessary because 
strict quality assurance/quality control are essential for methods that 
are not fully developed for the contaminants being tested because of 
the small sample size. It is important to note that this testing

[[Page 23414]]

would be from a limited number of systems and, for any particular 
system, would only be done over a one-year timeframe in the five year 
contaminant listing cycle. If the contaminant occurrence were frequent 
enough or in sufficiently high concentrations to warrant regulation, 
future testing for the contaminant might not occur for another three to 
five years (i.e., after promulgation of a final regulation for that 
contaminant.
    The Screening Survey would occur one or two times during the five-
year listing cycle. EPA expects that this Screening Survey monitoring 
would occur for groups of contaminants, rather than for one contaminant 
at a time. Systems selected for the Screening Survey would monitor at 
the same frequency as for contaminants under Assessment Monitoring. 
Should implementation of the analytical method for a particular 
contaminant become a problem, the contaminant might move into the 
category of Pre-Screen Testing, described below.
3. Pre-Screen Testing
    The third tier of the proposed monitoring program is ``Pre-Screen 
Testing'' for contaminants with analytical methods in an early stage of 
development. Pre-Screen Testing means sampling, testing, and reporting 
of the listed contaminants that may have newly emerged as drinking 
water concerns and, in most cases, for which methods are in an early 
stage of development. Pre-screen testing will be performed to determine 
whether a listed contaminant occurs in sufficient frequency in the most 
vulnerable systems or sampling locations to warrant its being included 
in future Assessment Monitoring or Screening Surveys. Pre-Screen 
Testing requirements will only apply to a contaminant through 
additional rulemaking.
    EPA will select a limited number of systems (up to 200) to conduct 
Pre-Screen Testing, through the use of a random number generator, 
selected from up to 25 most vulnerable systems identified by each 
State. Up to 200 systems, a smaller sample size than under the 
Screening Survey or Assessment Monitoring, are considered sufficient 
for this type of monitoring because monitoring would occur at systems 
anticipated to have the contaminants, based on the characteristics of 
the contaminants, system operation, climatic conditions, and land and 
water resource use. This monitoring is to determine whether the 
contaminant can be found in any public water system under most likely 
occurrence conditions specific to the contaminant, and not to determine 
the extent of occurrence. The portion (e.g., 100 to 150) of these 200 
systems may be a different subset of small systems serving 10,000 or 
fewer persons than those selected for the national representative 
sample. The reason for this different subset is that States should 
identify the systems that are representative of the most vulnerable 
conditions for the contaminants specified for Pre-Screen Testing. These 
most vulnerable systems may not be those conducting Assessment 
Monitoring or the Screening Survey. It is possible, though, that some 
overlap of systems doing Assessment Monitoring and Pre-Screen Testing 
could occur.
    EPA is proposing under Pre-Screen Testing that the selected systems 
use EPA's designated or approved (as indicated above for the Screening 
Survey testing of samples from large systems) laboratory or 
laboratories to conduct this testing. The reason for this proposed 
testing approach is that the analytical methods expected to be used 
will have just emerged from research development and other laboratories 
will not have had the opportunity to use them, which could involve 
extensive investment in equipment and training. Rather than cause this 
investment to occur for contaminants which have uncertain occurrence in 
public water systems, EPA would develop the initial methods 
sufficiently to test for the contaminants and actually apply them to 
samples that are most likely to have the contaminants to determine 
whether further action is warranted and additional method development 
is needed.
    The Pre-Screen Testing option might include (1) contaminants on 
List 3, for which EPA has limited data on occurrence in drinking water 
and does not expect to have methods developed by the time this 
regulation is promulgated, or (2) contaminants not on the CCL that 
become a concern, such as through the Governors' petition process. The 
purpose of Pre-Screen Testing would be to determine whether the methods 
in early development will provide positive results in conditions under 
which the contaminants are most likely to occur.
    Under this approach, once EPA has a method sufficiently developed, 
it would require States to identify at least 5 and not more than 25 
systems which might be most vulnerable to the listed contaminants. 
States would select these systems from all community and non-transient 
noncommunity systems serving less than 10,000 persons and systems 
serving more than 10,000 persons. Selection criteria for these systems 
include States determination of systems most vulnerable to the 
specified contaminants and numbers of systems per State based on the 
number of persons served in each size category of system. The States 
would send the list of systems, the modification of their State 
Monitoring Plans for systems serving 10,000 or fewer persons to add the 
selected systems of this size, and the reasons for their selection, 
considering the characteristics of the contaminants, precipitation, 
system operation, and environmental conditions, to the EPA Regional 
Office. EPA would select up to 200 PWSs nationwide from this pool of 
State-identified vulnerable systems that must submit samples of the 
specified contaminants. Some small systems selected may not be part of 
the national representative sample of 800 systems selected for 
Assessment Monitoring. Hence, some small systems may only be required 
to assist with Pre-Screen Testing. States or the EPA Regional Office 
would provide instructions to the systems for the necessary sampling 
and subsequent shipping to the EPA laboratory. At this time, EPA 
believes that the contaminants to which Pre-Screen Testing is likely to 
apply are those listed in this Preamble in Table 5, List 3, and in the 
proposed rule at Sec. 141.40(a)(3) Table 1, List 3. Sampling and 
testing done for Pre-Screen Testing would most likely occur in the 
later years of the five-year contaminant listing cycle. This approach 
will assist EPA in refining the methods for these contaminants. If EPA 
finds any substantial frequency of occurrence, the contaminants could 
either become part of the Screening Survey or part of Assessment 
Monitoring in future UCM lists. Since these methods could only be 
applied under highly controlled test conditions and EPA would be 
refining the methods, EPA would pay for the shipping and testing of 
these samples for small monitored systems selected to participate and 
large systems would pay for the shipping and testing of samples at EPA 
approved laboratories.
4. Option to the Three-Tiered Approach
    The principal option considered in developing this proposal for the 
type of monitoring required was to require all large systems and small 
systems included in State Monitoring Plans to monitor for all the 
contaminants on the UCM Monitoring List, phasing in the contaminants as 
their respective methods became approved for testing by certified 
laboratories. This approach had the problem of attempting to use 
recently developed methods in an extensive monitoring program without

[[Page 23415]]

multi-matrix, multi-laboratory testing of the methods. This option 
would cost $50 million more annually than the proposed three-tiered 
approach because the high cost of the methods, especially on List 3. 
Also, the large PWSs with laboratories as well as independent 
laboratories would have potentially large investments in testing 
equipment that it might not have made for just a one year monitoring 
activity, especially if EPA decided not to regulate the particular 
contaminant. Alternatively, waiting until an analytical method had been 
thoroughly evaluated and refined for broad use in testing at reasonable 
cost to all systems would result in few of the contaminants on Lists 2 
or 3 ever being monitored for during the five year listing cycle. This 
would postpone the collection of useful data with which decisions might 
be made relative to whether to regulate the contaminants.

D. Monitoring Requirements Under the Proposed UCMR

1. Monitoring Frequency
(a) Systems Serving More Than 10,000 Persons
    Chemical Contaminants. The number of persons served affects 
exposure to contaminants and resources necessary to undertake a 
monitoring activity. The proposed UCMR program requires large systems 
serving more than 10,000 persons to monitor at each entry point to the 
distribution system whether or not the system applies treatment, but if 
it does, then it must monitor after treatment. EPA is also to consider 
the source of water relative to these monitoring requirements (SDWA 
section 1445(a)(2)(A)). Over the twelve-month period of monitoring, EPA 
proposes that systems sample from all entry points representing all 
sources of water used over the monitoring period. Surface water-
supplied systems would monitor each of these points every three months 
within a twelve-month period and ground water-supplied systems would 
monitor each of these points two times, six months apart. Today's 
proposed monitoring frequency for surface water systems is the same as 
in the current program. For ground water systems, the proposed two 
samples must be six months apart, increasing this monitoring from one 
sample under the current program. The reasons for this increase are 
that while ground water typically moves slowly, one sample is 
insufficient to characterize water quality at any particular location 
and would not provide evidence of any changes over a longer period of 
time. From a statistical standpoint, one sample is not representative 
and would not allow the data to be used for exposure assessment which 
uses an average annual rate. At State discretion, this monitoring may 
be coordinated with compliance monitoring for regulated contaminants. 
This proposed frequency applied to the average of 6.2 entry points to 
the distribution system for this system size will provide sufficient 
data for an adequate statistical analysis of the varied conditions in 
which these systems are located.
    One of the monitoring events for both surface water and ground 
water systems must occur at the most vulnerable time of year for the 
PWS. The rationale for this approach is that it provides results 
representing potential variation in contaminant concentration over a 
year. This variation of concentration is necessary to evaluate exposure 
related to contaminant occurrence results. While some systems that 
perform compliance monitoring on a quarterly basis could collect UCMR 
samples coincident with their compliance samples and would therefore 
provide data on the range of variation, other systems may only conduct 
compliance monitoring once every third year and for one year every five 
years only, and would therefore have to collect additional samples 
under the UCMR. While one UCMR sample could be collected coincident 
with this compliance sample, EPA is proposing for ground water-supplied 
systems that a second sample be taken six months later to provide the 
necessary data on seasonal variation over a year to allow consistent 
exposure assessment to be done with a range of concentrations. 
Stakeholders supported this option. EPA proposes that all systems 
serving more than 10,000 persons and a representative sample of systems 
(about 800) serving 10,000 or fewer persons monitor under this 
frequency and schedule.
    Microbiological Contaminants. For microbiological contaminants, the 
sampling frequency would be two times, with samples collected each time 
at two different locations in the distribution system after treatment: 
a site representative of water in the distribution line received by the 
general population that the system serves and a site near the end of 
the distribution line representing the longest residence time. The 
frequency should capture the most vulnerable time as well as a time six 
months later to provide an average exposure. Furthermore, precipitation 
patterns may be a major factor in contaminant occurrence. Thus, 
frequency should be tailored to times of the year of significant 
vulnerability because increased seasonal precipitation may carry these 
contaminants at higher concentrations than other times during the year.
(b) Systems Serving 10,000 or Fewer Persons
    EPA proposes that approximately one third of the systems serving 
10,000 or fewer persons in the representative sample described below, 
be sampled each year over a three year period at the frequencies 
indicated in (a) above to allow a relatively even submission of samples 
to be managed and tested by the EPA laboratory. Since EPA will pay for 
the reasonable costs of monitoring (i.e., containers, shipping, and 
testing) for this representative sample, including Assessment 
Monitoring, Screening Survey, and Pre-Screen Testing, at its designated 
laboratories, it would need to be able to manage the number of samples 
being received at any time.
2. Monitoring Time for Vulnerable Period
    Water quality studies and monitoring throughout the United States 
have clearly shown that contaminant occurrence and/or concentration 
vary over time, both seasonally as well as from year to year. The 
seasonality of occurrence, or period of peak concentration of 
contaminants commonly varies with seasonal changes in the hydrologic 
cycle in relation to the source of contaminants and their fate and 
transport characteristics. Particularly for land-applied or land-
disposed contaminants, the increased flux of water mobilizes the 
contaminants and moves them into surface or ground water flow systems. 
For the most vulnerable of water systems, such as surface waters, 
unconfined shallow ground water and karst flow systems, for example, 
contaminant occurrence or peak concentrations typically occur during 
annual runoff and recharge periods. For much of the eastern United 
States, east of the Rocky Mountains, many studies have shown the season 
of greatest vulnerability for contaminant occurrence is the late-
spring, early-summer runoff-recharge period, particularly for 
contaminants such as pesticides and nitrate (e.g., Larson et al., 1997; 
Barbash and Resek, 1996; Hallberg, 1989a, b). For deeper, more confined 
ground water systems, defining vulnerable periods is much more 
difficult. The exact flow path and time of travel are much greater and 
more complex and are dependent upon many factors unique to a particular 
well and aquifer setting (e.g., Hallberg and Keeney, 1993). There is no 
generality

[[Page 23416]]

that can be applied to these latter settings.
    Because occurrence may vary seasonally, it is important to try to 
capture these vulnerable periods in a one-time survey of contaminant 
occurrence such as the UCMR. Statistical studies of sampling strategies 
in surface water (e.g., Battaglin and Hay, 1996) have shown that 
incorporating sampling during spring and early summer runoff periods 
provides a more accurate representation of annual occurrence than 
random quarterly sampling (that can avoid these months). Ground water 
studies (e.g., Pinsky et al., 1997) suggest that the more vulnerable 
ground water settings also show peaks during these periods. The default 
vulnerable period for sampling for the UCMR has been designated to 
coincide with this period of peak vulnerability for much of the United 
States: one sample must be collected during May, June, or July, unless 
the State has better information to designate another period. Also, for 
surface waters, three additional samples will be collected throughout 
the year, and for ground water systems, one additional sample will be 
collected six months later. This additional sampling would also capture 
the winter recharge and runoff period that may be more vulnerable in 
the western coastal regions or warmer southern climates for some 
contaminants. In the case of some deeper ground water systems, States 
or systems may have additional knowledge of seasonal vulnerability 
patterns, in which case the State can designate an alternative period 
for sampling. EPA requests public comment on the specification of the 
most vulnerable time for monitoring and how it should be determined.
3. Monitoring Location
    In Sec. 141.40(a)(3), today's proposal identifies entry points to 
the distribution system after any treatment representative of each 
water source in use over the twelve-month period of Assessment 
Monitoring as the sampling locations for organic chemicals and the 
distribution system (a site representative of water in the distribution 
line received by the general population that the system serves and a 
site near the end of the distribution line representing the longest 
residence time) for the microbiological contaminant. Sampling at entry 
points to the distribution system after any treatment follows the 
existing regulatory approach for currently regulated contaminants and 
provides data for exposure assessment.
(a) Chemical Contaminants
    The chemicals in this proposed rule are all compounds that would 
enter a public water supply from the external environment (in contrast 
to disinfection byproducts, for example) and the proposed monitoring 
location is at the entry point to the distribution system after 
treatment, representing all sources of water used over the twelve-month 
monitoring period to ensure a nationally consistent data set and to 
provide consistent data for exposure assessment.
(b) Microbiological Contaminants
    The sampling locations for microbiological contaminants are 
different from those for chemical contaminants because the most likely 
locations to observe microbiological contaminants may be in the 
distribution system, or, for some, in source water. This is, in part, 
because of the difficulty of testing to isolate many microbiological 
contaminants. Two sampling locations are proposed in this regulation. 
One of the samples would be at the site below a representative entry 
point to the distribution system that is used for taking total coliform 
samples; this sample would represent general exposure. The second 
sample would be near the end of the distribution line that has the 
longest residence time, representing the extreme exposure of the 
population at this point in the distribution system. Over the twelve-
month period of monitoring, EPA proposes that systems sample at 
locations representing all sources of water used over the monitoring 
period, to the extent possible.
    Currently, it is not possible to assess whether or not all of the 
microorganisms (including those on List 3) are likely to be found at 
any one sampling location, or that one sampling location is the best 
place to sample for them all. The occurrence information needs differ 
for different microorganisms. Different parts of the water supply and 
distribution system may be more likely locations to find particular 
microbiological contaminants. Therefore, the sampling location for 
monitoring each microorganism may need to be tailored in the future to 
the individual organism and the relative ease of finding it in the 
water of concern.
    As a result, for the microbiological contaminants being proposed 
for Lists 2 and 3 today, EPA has not identified a sampling location or 
locations. For some of the microbiological contaminants, source water 
may be the most appropriate sampling location because of the capability 
of the methods available. In any case, EPA would specify a sampling 
location at the time a microbiological contaminant would be proposed to 
become a required monitoring contaminant and ask for public comment at 
that time.
4. Quality Control Procedures for Sampling and Testing
    To assure that the data collected under this proposed regulation 
are of sufficient quality to meet the requirements for the uses of the 
resulting data, EPA is proposing the analytical methods and procedures 
to be used in obtaining the monitoring data in Sec. 141.40(a)(3) and 
appendix A. Also, additional guidance for quality control and 
contaminant confirmation are specified in the ``UCMR Analytical Methods 
and Quality Control Manual.'' This proposed regulation covers quality 
control steps for all sampling and testing under this program. In 
addition, the draft guidance manual is available for review and public 
comment with this proposed regulation. Today's proposed rule would 
require that all monitored systems follow these methods and procedures 
in organizing and conducting their unregulated contaminant monitoring 
and testing. Systems would also have to ensure that the laboratories 
they use to test samples use the proposed methods and procedures. The 
specific quality control requirements addressed in Sec. 141.40(a)(3) 
and appendix A of the proposed rule are: sample collection/
preservation; sample transport; sample and sample extract holding time 
and storage; sample analyses/quality control requirements, including 
quality control (QC) requirements, calibration, calibration 
verification, laboratory reagent (method) blank, quality control 
sample, laboratory duplicates, sample matrix spike (MS) and matrix 
spike duplicate (MSD), internal standard, surrogate standard, method 
detection limit determination, minimum reporting level; confirmation; 
and reporting requirements. EPA believes that requiring the quality 
control requirements for unregulated contaminant sampling and testing 
in the proposed rule will enable the Agency to have higher confidence 
in determining the extent and range of concentrations for the 
contaminants on the UCM List, since they are not regularly tested for 
nationally.
5. Monitoring of Routinely Tested Water Quality Parameters
    In addition to the contaminants to be monitored, several chemical 
and physical parameters are important indicators of water quality and 
may contribute to the likelihood of the

[[Page 23417]]

contaminants being found in drinking water. EPA requests public comment 
on whether it should require the monitoring and reporting of these 
routinely tested parameters, usually associated with water quality 
analyses, to provide for a more thorough scientific understanding of 
the occurrence of unregulated contaminants. It is not EPA's intent to 
add these chemical and physical parameters to the unregulated 
contaminant monitoring list, but rather as supplementary data about the 
sample results which will facilitate their interpretation and use in 
regulatory decisions. The water quality parameters and their methods 
for which EPA seeks comment are specified in Table 6, Analytes Approved 
for Water Quality Parameters.

                                                     Analytes Approved for Water Quality Parameters
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                           Methodology
                Analyte                -----------------------------------------------------------------------------------------------------------------
                                            EPA method                Standard methods \1\                                   Other
--------------------------------------------------------------------------------------------------------------------------------------------------------
pH....................................             2150.1  4500-H+ B                                   ASTM D1293-84 3
                                                   2150.2                                              ASTM D1293-95 3
Turbidity.............................           4 5180.1  2130 B 4                                    GLI Method 2 4,6
Temperature...........................  .................  2550                                        .................................................
Free Residual Chlorine................  .................  4500-Cl D                                   ASTM D 1253-86 3
                                                           4500-Cl F
                                                           4500-Cl G
                                                           4500-Cl H
Total Residual Chlorine...............  .................  4500-Cl D                                   ASTM D 1253-86 3
                                                           4500-Cl E 4
                                                           4500-Cl F
                                                           4500-Cl G 4
                                                           4500-Cl I
Chlorine Dioxide Residual.............  .................  4500-ClO2 C
                                                           4500-ClO2 D
                                                           4500-ClO2 E
Ozone Residual........................  .................  4500-O3 B
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ The 18th and 19th Editions of Standard Methods for the Examination of Water and Wastewater, 1992 and 1995, American Public Health Association, 1015
  Fifteenth St. NW, Washington D.C., 20005.
\2\ Methods 150.1 and 150.2 are available from US EPA, NERL, 26 W. Martin Luther King Dr., Cincinnati, Ohio 45268. The identical methods are also in
  ``Methods for Chemical Analysis of Water and Wastes,'' EPA-600/4-79-020, March 1983, available from the National Technical Information Service (NTIS),
  U.S. Department of Commerce, 5285 Port Royal Rd., Springfield, Virginia 22161, PB84-128677. (Note: NTIS toll-free number is 800-553-6847.)
\3\ Annual Book of ASTM Standards, Editions 1994 and 1996, Volumes 11.01, American Society for Testing and Materials, 1015 Fifteenth Street NW,
  Washington, DC 20005. Version D1293-84 is located in the Annual Book of ASTM Standards, 1994, Volumes 11.01. Version D1293-95 is located in the Annual
  Book of ASTM Standards, 1996, Volumes 11.01.
\4\ ``Technical Notes on Drinking Water,'' EPA-600/R-94-173, October 1994, Available at NTIS, PB95-104766.
\5\ ``Methods for the Determination of Inorganic Substances in Environmental Samples,'' EPA-600/R-93-100, August 1993. Available at NTIS, PB94-121811
\6\ GLI Method 2, ``Turbidity,'' November 2, 1992, Great Lakes Instruments Inc., 8855 North 55th St., Milwaukee, Wisconsin 53223.

6. Relation to Compliance Monitoring Requirements
    Currently, compliance monitoring for regulated contaminants is 
coordinated on a three-year cycle, with all public water systems that 
are required to monitor sampling for specific contaminants at a minimum 
of one year every three, six, or nine years, depending on the 
contaminant and its occurrence in the system. The current and proposed 
Unregulated Contaminant Monitoring Regulations require monitoring 
during one year every five years. While these may seem out-of-cycle 
with one another, EPA is proposing to implement UCMR so that public 
water systems only have to monitor for unregulated contaminants during 
one twelve-month period every five years, unless the State determines 
that PWSs should conduct more frequent monitoring. Hence, the 
compliance monitoring and the UCMR monitoring can be coordinated, to 
the extent practical, by conducting UCMR monitoring during a coincident 
year during which compliance monitoring is required. The years within 
which the unregulated contaminant monitoring are proposed to occur are 
specified in Sec. 141.40(a)(3), Table 1, column 6.
7. Previous Monitoring of the Contaminants Proposed for the Monitoring 
List
    Some PWSs may have previously monitored for some of the 
contaminants identified on the proposed UCM List because of local or 
State concerns about the possibility of those contaminants occurring in 
drinking water. While this monitoring may have provided adequate 
results for their purposes, such results may not be comparable to 
results under this revised UCM regulation because of differences in 
sampling and analytical protocols, as well as the sampling period. 
Other factors compound the problem of comparability, such as: (1) 
Monitoring methods may have improved; (2) water quality changes over 
time; and (3) today's proposal requires reporting of a net increase of 
eight additional data elements, which would allow various, consistent 
comparisons to be made and data to be aggregated nationally based on 
current science and quality assurance/quality control consistency. 
Therefore, EPA is not proposing that monitoring results from previous 
monitoring be used in place of the monitoring under this revised 
regulation.
8. Regulatory Options Considered for Large Systems
    Regulatory options considered for large systems (small systems are 
addressed under III.F., ``Representative sample of systems serving 
10,000 or fewer persons''):
(a) Which Large Systems Should Monitor
    Today's proposal at Sec. 141.40(a)(1)(ii) requires all large 
systems to monitor under the UCMR. The rationale is that the 1996 SDWA 
amendments only set aside a subset of small systems to

[[Page 23418]]

monitor, but did not do so for large systems. Public input resulting 
from two Stakeholders meetings (Washington, DC; Dec.2-3, 1997; June 3-
4, 1998) on this proposed rule supported the option that all large PWSs 
should monitor.
    The only option considered by EPA was a representative sample of 
large systems. Stakeholders at the two Stakeholders meetings indicated 
above generally opposed this. Furthermore, the large system 
representatives at the meeting indicated that to ensure public health 
protection, they would monitor for all contaminants on any EPA drinking 
water unregulated contaminant monitoring list.
(b) Monitoring Frequency
    Other monitoring frequencies for the UCMR were considered and 
rejected:
    Ground water: Remaining at one time for one year every five years 
for ground water systems, as under the current program, was rejected 
because one sample is not considered representative and does not 
provide sufficient data about a system that can be averaged to develop 
a national exposure estimate. Four samples every three months were 
rejected because most ground water does not change that much over 
shorter periods of time and the results would, therefore, not provide 
additional useful information cost-effectively.
    Surface water: One or two samples in a year were considered, but 
rejected because these numbers of samples are too few to reflect the 
seasonal changes in this source of water. Furthermore, seasonal 
variation is different in different parts of the country. More frequent 
sampling of surface water is important to capture the duration of time 
that higher or lower concentrations of contaminants are observed to 
apply those results in developing an average concentration over a year 
for conducting exposure assessment.
    Compliance Monitoring Schedule: Another option EPA considered is 
quarterly monitoring for one year every three years for both surface 
and ground water systems, in complete coincidence with the standard 
compliance cycles. However, the compliance cycles (with three, six, and 
nine year components) are not in synchrony with the new UCMR and CCL 
five-year cycles. This option was rejected because of the 
implementation difficulties in adjusting a staggered three-year cycle 
of monitoring to fit into a five-year UCM listing cycle. This approach 
would result in some systems having one monitoring year and others 
having two monitoring years. Also, for many ground-water systems not on 
a quarterly compliance monitoring schedule, a minimum of two samples 
six months apart is adequate to address variation in concentrations and 
to provide an average annual concentration for exposure assessment.
(c) Monitoring Location
    Some States currently require source water monitoring as a more 
stringent requirement for chemical contaminants because it requires the 
testing of samples before any treatment that might reduce 
concentrations of contaminants. If the objective is exposure assessment 
(after treatment), source water monitoring would provide information 
for assessing potential exposure to acute contaminants should treatment 
fail. Source water monitoring would also provide useful information for 
treatment and source water protection analysis in future regulatory 
analyses that would examine a full range of control alternatives 
including contaminant treatments or controls in the watershed. Source 
water monitoring would give an indication of concentrations of 
contaminants that would need to be treated, of a measure of benefits 
from existing treatment if the occurrence of an unregulated contaminant 
is linked with a regulated contaminant being treated, and of the types 
of locations at which watershed management practices might be targeted. 
However, additional expense would be involved to monitor source water 
nationally. Other means of obtaining source water quality data exist, 
such as State or U.S. Geological Survey data for ambient water quality 
in watersheds and aquifers. At this time, EPA is not requiring source 
water monitoring because of the existence of other sources of 
information and the need to focus the available resources of the Agency 
on exposure after drinking water treatment for the contaminants on List 
1.
    During rule development, stakeholders suggested that an alternative 
location for Aeromonas and other microbiological contaminants might be 
the sampling point used for coliforms. The coliform sampling point, 
however, may not be representative for testing Aeromonas hydrophilla, 
which tends to be found further into distribution systems at low 
disinfection residual levels. A low chlorine residual provides the 
environment for the surviving organisms to recolonize and grow. To 
enable a balanced assessment of Aeromonas occurrence, EPA is proposing 
to require sampling at both a representative site in the distribution 
system and a site near the end of the distribution line with the 
longest residence time.

E. Waivers

1. Waivers for Systems Serving More Than 10,000 Persons
    Section 1445(a)(2)(F) of SDWA allows a State to obtain a waiver of 
UCM for specific contaminants if the State demonstrates that the UCM 
listing criteria do not apply in that State. These criteria are:
    (a) The criteria for listing a contaminant in the occurrence 
priorities list in the CCL; and
    (b) Whether an analytical method exists for the contaminant.
    When a State makes such a demonstration for a specific contaminant 
on the monitoring list, EPA is proposing to waive monitoring for that 
contaminant in that State for large systems (serving more than 10,000 
persons) only.
    Stakeholders indicated that waiver requirements should be 
sufficiently stringent to obtain the most representative national data 
possible, including non-detections of contaminants on the UCM List. 
Since only the UCM listing criteria in (a) are relevant to a State-
specific waiver and based on stakeholders' concern that the waiver be 
narrowly applied, EPA is proposing that this waiver be applied only 
where the State can demonstrate that the contaminant has not been used, 
applied, stored, released, or disposed of, or does not occur through 
natural processes (such as growth in a system or air deposition) in the 
State for the past fifteen years. Source Water Assessments provided for 
under sections 1453 and 1428(b) of SDWA may be used as the basis for 
these waivers if the Assessments specifically address the 
contaminant(s) on the UCM List for which a waiver is sought. Table 7, 
Uses and Environmental Sources of Contaminants Proposed for the 
Monitoring List, presents the uses and sources of the contaminants 
being proposed for the Unregulated Contaminant Monitoring List. A State 
would need to apply for a waiver from monitoring for specific 
contaminants and receive EPA approval to waive the monitoring.
    While some chemical contaminants may only be discharged into the 
environment in regional or local areas, microbiological contaminants 
may be ubiquitous. However, previous monitoring + results over time may 
provide information useful to waiver determinations for microbiological 
contaminants.

[[Page 23419]]

2. Waivers for Small Systems in State Plans
    EPA is proposing that no waivers be granted for small systems 
serving 10,000 or fewer persons in State Plans for the national 
representative sample. Stakeholders also supported this position. The 
systems in State Plans will be statistically selected with the 
assumption that all systems in a particular size category and water 
source type have an equal probability of being selected. Non-detections 
are just as important as detections of contaminants for national 
analysis. Waiving contaminants to be monitored in certain States not 
expecting to have such contaminants biases the representative sample 
toward detections. Selecting the small systems to be included in the 
State Monitoring Plans for the representative sample through a 
statistical process effectively waives ninety-seven percent of the 
systems from the proposed monitoring requirements (based on using 99 
percent confidence level with three percent allowable error). 
Therefore, EPA rejected waivers for systems serving fewer than 10,000 
persons because this option would be contradictory to obtaining a 
scientifically sound data set that provides the basis for a scientific 
statistical analysis.

  Table 7.--Uses and Environmental Sources of Contaminants Proposed for
                           the Monitoring List
------------------------------------------------------------------------
                                                  Use or environmental
       Contaminant name              CASRN               source
------------------------------------------------------------------------
                     Proposed Chemical Contaminants
------------------------------------------------------------------------
1,2-diphenylhydrazine.........        122-66-7  Used in the production
                                                 of benzidine and anti-
                                                 inflammatory drugs.
2-methyl-phenol...............         95-48-7  Released in automobile
                                                 and diesel exhaust,
                                                 coal tar and petroleum
                                                 refining, and wood
                                                 pulping.
2,4-dichlorophenol............        120-83-2  Chemical intermediate in
                                                 herbicide production.
2,4-dinitrophenol.............         51-28-5  Released from mines,
                                                 metal, petroleum, and
                                                 dye plants.
2,4-dinitrotoluene............        121-14-2  Used in the production
                                                 of isocyanate, dyes,
                                                 and explosives.
2,4,6-trichlorophenol.........         88-06-2  By-product of fossil
                                                 fuel burning, used as
                                                 bactericide and wood/
                                                 glue preservative.
2,6-dinitrotoluene............        606-20-2  Used as mixture with 2,4-
                                                 DNT (similar uses).
Acetochlor....................      34256-82-1  Herbicide used with
                                                 cabbage, citrus,
                                                 coffee, and corn crops.
Alachlor ESA..................  ..............  Degradation product of
                                                 alachlor, an herbicide
                                                 used with corn, bean,
                                                 peanut, and soybean
                                                 crops to control
                                                 grasses and weeds.
DCPA di-acid degradate........       2136-79-0  Degradation product of
                                                 DCPA, an herbicide used
                                                 on grasses and weeds
                                                 with fruit and
                                                 vegetable crops.
DCPA mono-acid degradate......        887-54-7  Degradation product of
                                                 DCPA, an herbicide used
                                                 on grasses and weeds
                                                 with fruit and
                                                 vegetable crops.
DDE...........................         72-55-9  Degradation product of
                                                 DDT, a general
                                                 insecticide.
Diazinon......................        333-41-5  Insecticide used with
                                                 rice, fruit, vineyards,
                                                 and corn crops.
Disulfoton....................        298-04-4  Insecticide used with
                                                 cereal, cotton,
                                                 tobacco, and potato
                                                 crops.
Diuron........................        330-54-1  Herbicide used on
                                                 grasses in orchards and
                                                 wheat crops.
EPTC..........................        759-94-4  Herbicide used on annual
                                                 grasses, weeds, in
                                                 potatoes and corn.
Fonofos.......................        944-22-9  Soil insecticide used on
                                                 worms and centipedes.
Linuron.......................        330-55-2  Herbicide used with
                                                 corn, soybean, cotton,
                                                 and wheat crops.
Molinate......................       2212-67-1  Selective herbicide used
                                                 with rice, controls
                                                 watergrass.
MTBE..........................       1634-04-4  Octane booster in
                                                 unleaded gasoline.
Nitrobenzene..................         98-95-3  Used in the production
                                                 of aniline, which is
                                                 used to make dyes,
                                                 herbicides, and drugs.
Prometon......................       1610-18-0  Herbicide used on annual
                                                 and perennial weeds and
                                                 grasses.
Terbacil......................       5902-51-2  Herbicide used with
                                                 sugarcane, alfalfa, and
                                                 some fruit, etc.
Terbufos......................      13071-79-9  Insecticide used with
                                                 corn, sugar beet, and
                                                 grain sorghum crops.
------------------------------------------------------------------------
                      Microbiological Contaminants
------------------------------------------------------------------------
Adenoviruses..................             N/A  Fecal sources; hand to
                                                 mouth transmission.
Aeromonas hydrophila..........             N/A  Present in all
                                                 freshwater and brackish
                                                 water.
Cyanobacteria (Blue-green                  N/A  Blooms in surface water
 algae), other freshwater                        bodies; produce toxins.
 algae and their toxins.
Caliciviruses.................             N/A  Contaminated food and
                                                 water, raw shellfish.
Coxsackieviruses..............             N/A  Fecal sources; hand to
                                                 mouth transmission.
Echoviruses...................             N/A  Fecal sources; hand to
                                                 mouth transmission.
Helicobacter pylori...........             N/A  Fecal sources; hand to
                                                 mouth transmission.
Microsporidia.................             N/A  Occurs in rivers, ponds,
                                                 lakes, and unfiltered
                                                 water.
------------------------------------------------------------------------

F. Representative Sample of Systems Serving 10,000 Persons or Fewer

    As required by section 1445(a)(2) (A) and (C), the regulation 
proposes that only a representative sample of public water systems 
serving 10,000 or fewer persons would have to monitor. As previously 
explained, only community and non-transient non-community systems would 
be required to monitor for unregulated contaminants under this 
proposal. Therefore, the representative sample would include only 
community and non-transient non-community systems serving 10,000 or 
fewer persons. The representative sample would need to be of sufficient 
size to gather the necessary information on occurrence of unregulated 
contaminants to determine whether or not to regulate them, while not 
burdening every water system with the expense of monitoring. The number 
of systems selected within each of three size ranges of small systems 
would be based on the proportion of the State's population served by 
systems in that size range. (An example appears below under (5)(a), 
State Plans for the Representative Sample.) The small systems in the 
national representative sample would be selected using a statistical 
random

[[Page 23420]]

sampling process. This process would utilize a random number generator 
to choose a statistically determined number of systems in each State 
and Tribe having ``treatment as a State'' status, considering the 
number of systems served by water source type (e.g., ground or surface 
water) and then system size category (i.e., 25 to 500 persons, 501 to 
3,300, and 3,301 to 10,000) within the water source type. EPA is 
proposing that the national representative sample become the basis for 
the State Monitoring Plan in each state. The use of this statistical 
approach is designed to take into account different system sizes, types 
of systems, the source of supply, contaminants likely to be found, and 
geographic location in each State. EPA believes that the end product of 
this statistical process applied to selecting systems to monitor must 
be data that are sufficient to answer questions about occurrence of 
contaminants on a national scale for use in exposure assessments and 
technology evaluations of alternative treatments at a PWS and in its 
watershed. These data should also be sufficient to answer questions at 
a broad multi-state scale, such as systems classified by size or source 
of water, particularly when combined with data for the 2,774 large 
systems.
    Under this proposal, small system monitoring would be too sparse to 
answer questions about occurrence at the scale of a single State. The 
number of systems required for evaluation of occurrences in a single 
state are far greater than, and thus more costly than, those needed for 
the broader national evaluations required under the Act to determine 
whether or not to regulate a contaminant.
1. System Size
    Based on statistics reported in the Safe Drinking Water Information 
System (SDWIS), the following numbers of systems (1997 data) by size 
will approximate the universe from which a representative sample of 
systems serving 10,000 or fewer people will be taken for this proposed 
national representative sample plan. These system size categories are 
proposed because they are used in other statutory and regulatory 
characterizations of systems, and are applied under the existing rule 
for unregulated contaminant monitoring for the scheduling of sampling. 
The relevant system and population information (1997) for systems 
serving 10,000 or fewer persons is:

----------------------------------------------------------------------------------------------------------------
                                                                                  Population served nationally
          Number of people served in PWS size range             Number of PWSs ---------------------------------
                                                                in size range         CWS             NTNCWS
----------------------------------------------------------------------------------------------------------------
25 to 500....................................................           48,100        5,249,577        2,379,034
501 to 3,300.................................................           14,126       19,918,106        2,724,728
3,301 to 10,000..............................................            3,410       25,236,059          401,579
                                                              --------------------------------------------------
    Total....................................................           65,636       50,403,742        5,505,341
----------------------------------------------------------------------------------------------------------------

    Considering all community water systems and NTNCWS that do not 
purchase their water supplies, 65,636 PWSs are in the size range for 
small systems as defined in section 1445. Systems purchasing water from 
other systems are proposed to be excluded from this rule because they 
could bias results by potentially causing double counting of 
contaminant occurrence. EPA seeks public comment on whether systems 
purchasing water from other systems should be included in the 
representative sample, particularly for monitoring at the location of 
the longest residence time within a water distribution system.
2. System Type
(a) Public Water System Monitoring
    Under today's proposal, all public water systems serving 10,000 or 
fewer persons, except transient non-community systems, would be 
considered for monitoring, but only a subset would be selected for the 
national representative sample. Public water systems owned and/or 
operated on Tribal lands by Tribes would be treated as a separate group 
for the representative sample, rather than counting them within the 
State boundaries as systems in a particular State. EPA is proposing 
that the size of the representative sample and the specific systems 
required to monitor will be identified by EPA and sent to the States 
for review and inclusion in State Monitoring Plans (discussed below).
(b) Non-Transient Non-Community Water Systems
    Non-Transient Non-Community Water Systems (NTNCWS) represent 
schools, hospitals and other facilities in communities that serve the 
resident population but have their own water supply systems. 
Approximately 20,000 systems of this type exist in the United States. 
Today's proposed regulation at Sec. 141.40(a)(1)(iii) would include 
NTNCWS as a separate type of water system to be included in the 
representative sample for monitoring. Typically, these systems are 
closely associated with a local resident population and may be a 
significant source of water consumed by that population over a 
lifetime. Indeed, these systems may be a major source of water consumed 
by individuals resident in a community. The selection of NTNCWS will 
use the same statistical process as for community water systems (CWS), 
with systems grouped within a State by water source type and size 
category. The reason for a separate category for NTNCWS is to avoid 
double-counting of population served when doing exposure assessments of 
both small CWS and NTNCWS, while allowing weighting of lifetime water 
consumption by system type.
(c) Transient Non-Community Systems
    Transient non-community water systems represent systems providing 
drinking water to transient populations such as at a restaurant in a 
rural location or a highway roadside rest area. About 97,000 of these 
systems exist in the United States; their location and type are highly 
variable. It would be difficult to extrapolate exposure from monitoring 
results, given the very short-term nature of the systems' use by 
individuals who may not be in the area for more than a few hours or 
days. Because of problems with implementation and cost for sampling 
such a large and highly variable set of typically very small systems, 
EPA is proposing to exclude transient systems from all unregulated 
contaminant monitoring requirements. In this regard, this proposal is 
consistent with the current UCM program. EPA seeks public comment on 
excluding transient non-community systems from State Monitoring Plans 
for the representative sample of systems to be monitored.

[[Page 23421]]

3. Geographic Location Within the State
    SDWA section 1445 specifies that State plans should consider 
``geographic location'' when selecting a representative sample. This is 
accomplished at the broadest level by selecting systems from each 
State. Yet within a State, the sources of water may not be evenly 
distributed across that State, especially surface waters. Cities 
transfer water across watershed boundaries, or move water from one 
State to another. To best represent water being consumed by 
individuals, EPA proposes to define ``geographic location'' in the 
representative sample proposed today as the location of the source of 
water, rather than as an even distribution of points across the State. 
For example, if 40 percent of the persons in a State obtain their water 
from one water source type (e.g., surface water), 40 percent of the 
systems selected as representative should be from that source type, 
even if this results in points unevenly distributed across the State. 
This distribution should be accommodated by the population-weighted 
statistical sample selection.
4. Likelihood of Finding Contaminants
    Section 1445(a)(2)(A) requires that the UCMR program take into 
account the likelihood of finding a contaminant in establishing 
variable monitoring requirements for systems. This proposal is intended 
to allow the UCMR program to focus on monitoring for contaminants that 
are expected to be found nationally or among several regions of the 
United States. Therefore, the expectation of finding the contaminants 
nationally is fundamental to the approach of the representative sample 
and its statistical method of random selection. However, the 
``likelihood of finding contaminants'' factor is accommodated by the 
step-wise three-tiered approach of Pre-Screen Testing, Screening Survey 
and Assessment Monitoring.
5. State Plans for the Representative Sample
    As discussed above, section 1445 (a)(2)(C) allows States to develop 
State Monitoring Plans (also referred to as ``State Plans'') to assess 
the occurrence of unregulated contaminants for small systems in the 
State. EPA believes that the development of State Plans is affected by 
two other considerations: (i) The State plans must fit together into a 
national representative sample so that it is, in fact, nationally 
``representative,'' and (ii) EPA will pay for the reasonable costs of 
testing and laboratory analysis necessary to carry out monitoring under 
State Plans, pursuant to section 1445(a)(2)(C)(ii).
(a) Representative State Plans
    To have representativeness at the national level while at the same 
time allowing each State to develop a ``State Plan,'' the testing for 
which will be funded by EPA, the Agency proposes the following 
approach: Based on a statistical random selection process applied to 
all CWS and NTNCWS nationally using the average population served by 
systems and water source type (surface or ground water to ensure 
geographic coverage) within service-size category (25-500, 501-3,300, 
3,301-10,000 persons), EPA will select at least twice as many CWS and 
NTNCWS as required for the national representative sample to allow for 
replacements of systems, if necessary. EPA will use a random number 
generator to select these systems. These systems will be divided into 
an ``initial plan'' list and a ``replacement list.'' The representative 
sample will be allocated on a State basis, considering the number of 
persons served by each service size category and water source type. The 
``initial plan'' list of systems will identify those systems 
tentatively selected by EPA for each State. For the State plan, the 
State can adopt the EPA-selected systems on the ``initial plan'' as its 
plan, or review the list to determine which systems should be removed 
from the list because of such factors as closure, merger, or water 
purchase arrangement and submit a modified plan. The State would then 
select the next water system(s) from the ``replacement list'' to 
replace the system(s) removed, thus creating a ``modified plan.'' The 
State, in either case, would inform the EPA Regional Office of the 
State's choice of plan (i.e., ``initial'' plan or ``modified'' plan) 
along with reasons for removing and replacing systems on the ``initial 
plan'' within 60 days of receiving the ``initial plan.'' If EPA has not 
received a response from the State, the EPA Regional Office will 
consult with the State before adopting the ``initial plan'' for that 
State as its State Plan. The State Plan would include a process for the 
State to inform the public water systems of their selection for the 
representative sample once the State has accepted the initial plan or 
prepared the modified plan and informed the EPA Regional Office of this 
action. The EPA Regional Office would inform systems if the State 
chooses not to accept or modify the initial plan. This approach ensures 
a nationally representative set of systems and allows a State 
flexibility to modify EPA's ``initial plan'' with minimal burden. EPA 
would develop and provide initial plans to States and Tribes in the 
first half of year 2000 to allow sufficient time for State/Tribal 
review and modification, and for informing systems selected for the 
State Plans.
    Statistical Approach. Under today's proposal, the representative 
sample of small public water systems would be composed of a subset of 
systems which, in the aggregate, represent the public water systems of 
the three small system size categories within the United States. Within 
a State, public water systems would need to be selected so that the 
proportion of persons served by the systems sampled is as close as 
possible to the proportion of persons served by that system size 
category within that State. The portion of the national representative 
sample within a State's boundaries would become that State's Monitoring 
Plan, after review and possible adjustment by the State. The number of 
systems to be sampled in each State would be proportional to the 
percentage of persons served by public water systems of that size in 
the United States who reside within that State.
    For the small systems considered, a representative sample size of 
approximately 800 systems would provide a confidence level of 99 
percent with an allowable error of plus or minus 1 percent. This number 
of systems is statistically derived to allow population weighting for 
exposure assessment, with results being useful for analysis of 
contaminant occurrence at small systems, as well as a national analysis 
of all system sizes. EPA would allocate systems to each State, water 
source type and system size using an average number of persons served 
divided into the population served by systems serving 10,000 or fewer 
persons in each system size category. This approach ensures that each 
State has systems allocated to it for its State Plan. To accomplish 
this distribution of systems to each State, EPA would add to the 
statistically derived number for the representative sample a sufficient 
number of systems to allow this allocation for each State to have a 
plan that would then fit into the national representative sample. EPA 
would also add systems for NTNCWSs to be represented as a distinct 
group for the purposes of exposure assessment. Once monitored, the 
results of the representative sample of small systems would then be 
combined with large system results in an overall national analysis of 
contaminant occurrence in systems. EPA believes that this sample size 
would provide an adequate level of confidence, considering size, type

[[Page 23422]]

(community and non-transient non-community water systems), and 
location. EPA also believes that this approach provides sufficient 
information for the decision processes drawing on UCMR monitoring data 
for systems serving 10,000 or fewer persons, while keeping testing 
costs at a manageable level for the contaminants in List 1 for 
Assessment Monitoring. This number of systems should be sufficient to 
evaluate statistically whether a contaminant occurs in a specified 
number of systems, such as 2 or 3 percent. This number of systems, 
confidence level and allowable error will enable EPA to: (1) Evaluate 
the statistical significance of contaminant occurrence with low 
frequency and (2) compute the percent of systems for occurrence 
nationally, combining the results of both small and large systems.
    Further rationale for using a small estimate of the number of 
systems and small allowable error (confidence interval) in calculating 
the number of systems to be included in the representative sample is 
provided in the monitoring results from previous unregulated 
contaminant monitoring under the existing program. EPA has results from 
over 28,000 systems from the unregulated contaminant monitoring 
activities of 1988 to 1992 (the first round of unregulated contaminant 
monitoring under the current program) that indicate that of the 34 
contaminants required to be monitored at that time, 30 had occurrence 
at less that 2 percent of systems and, of those, 27 had occurrence at 
less than 1 percent of systems. Ten of these contaminants were selected 
for the Contaminant Candidate List ``Regulatory Priorities'' (see Table 
2) and all of these contaminants had occurrence at less than 2 percent 
of systems and eight, at less than 1 percent. Of the eight occurring at 
less than one percent of systems, four have health effects values 
within the concentration range of contaminant occurrence (Bromomethane 
(a pesticide), 1,3-dichloropropene (a pesticide), Hexachlorobutadiene 
(a solvent), and 1,1,2,2-Tetrachloroethane (a solvent)), and 
consequently may be considered for future regulation. These data point 
up the need to focus at the low end of occurrence. It also points to 
using a small allowable error (confidence interval) to ensure that 
based on statistics, EPA comes to the right decision on whether or not 
to regulate these contaminants, once the Agency has compared the 
results to health effects data.
    EPA also proposes that State Monitoring Plans include a 
representative sample of systems for Screening Survey monitoring of 
List 2 contaminants. The number of these systems, selected through the 
same statistical process from the systems used to conduct Assessment 
Monitoring, would be smaller (perhaps about 300) because the purpose of 
the Screening Survey is to test for contaminant presence in systems 
rather than testing for concentrations in an established percentage 
(such as 2 or 3 percent) of systems, as is the case for Assessment 
Monitoring. For the Screening Survey, if any low percent (e.g., 0.5 
percent) of systems have an occurrence of a contaminant, then the 
contaminant would be considered to occur at a level that would indicate 
that it should be included in the next round of Assessment Monitoring.
    If, based on prior information (e.g., from a Screening Survey or 
Pre-screen Testing), EPA determines that a more likely percent of 
systems with occurrence, another statistical confidence level and/or 
allowable error can provide scientifically defensible monitoring 
results, then EPA may apply a different likely percent of systems, 
confidence level, and/or allowable error to determine a smaller 
representative sample size. The statistical approach for specifying the 
number of systems by water source type (ground water, surface water or 
ground water under the direct influence of surface water) is as 
follows.
    The number of systems, n, required in the representative sample is 
determined by the allowable error (d) around the estimate 
for p, the proportion of systems which exceed a criteria (e.g., 
detection level) of interest. Based on the binomial distribution in 
statistics, the number of systems n which must be sampled for a likely 
proportion p of systems with contaminant occurrence within the 
allowable error d with confidence (1-a) is:
[GRAPHIC] [TIFF OMITTED] TP30AP99.000

    The number of systems to be sampled, n, does not depend on the 
total number of systems available. The number from the standard normal 
distribution, z, is obtained from a table of the standard normal 
distribution, representing a collection of data following a ``bell-
shaped curve'' which have a (standardized) mean of zero and standard 
deviation of one. The significance level, a, is the chance of the 
statistical interval of interest not containing the true value of the 
number being estimated, which, in this case, is the percent of systems 
having occurrence of the contaminants of concern on the UCM List. The 
true value for the percentage of systems having occurrence of the 
contaminants of concern can only be known if all systems are sampled, 
which is not proposed since section 1445(a)(2)(A) requires that only a 
representative subset of small systems be required to monitor for 
unregulated contaminants. Using this equation (1), the matrix below 
presents the required sample sizes for several values of allowable 
error and confidence level. For the national representative sample, an 
allowable error of .01 at a confidence level of 99% and a 
likely proportion of systems with contaminant occurrence of 1% was 
chosen. The possibilities for sample size, confidence level and 
allowable error considered in developing this approach are:

        Sample Sizes From a Universe of 65,600 Systems Based On--
------------------------------------------------------------------------
                                                  d, Allowable error
          Confidence level  (1-a)           ----------------------------
                                              .03    .02    .01    .005
------------------------------------------------------------------------
90 percent.................................     30     67    266   1,065
95 percent.................................     42     95    380   1,521
99 percent.................................     73    165    659   2,636
------------------------------------------------------------------------

    EPA believes that a representative sample size of 659 systems to be 
sufficient to draw conclusions about contaminant occurrence for small 
systems, based on 99% (.99) confidence level, 1% (.01) allowable error 
(confidence interval), and target percent of systems having occurrence 
of 1%. EPA chose a confidence level of 99% because it wanted to be that 
certain that the true proportion was included in its sample results. A 
5% chance that the window of error did not include the true proportion 
was considered too unacceptable, given the amount of money invested in 
monitoring and regulatory decisions. Based on the monitoring program, a 
1% risk (100-99% confidence) that EPA missed the target was more 
acceptable.
    A small allowable error (narrow confidence interval), such as 
1% (0.01), is important for evaluating the 
expected low percentages of systems having occurrence of any of the 
contaminants because EPA wants to be able to determine when the results 
of monitoring show that the percent of systems is distinguishable from 
zero or some other small value close to zero. Determining this outcome 
will help EPA decide which contaminants should receive primary focus 
for possible regulation after the results are evaluated with health 
effects data.

[[Page 23423]]

    To further consider the implications of the table above, suppose 
that after sampling these 659 systems, the proportion p which equaled 
or exceeded a detection level was 4% (0.04). The estimate of the true 
(unknown) proportion would be 0.04 0.01, or 3 to 5 percent. 
This interval has a 99% likelihood of containing the true proportion of 
systems having an occurrence of the contaminant of concern. There is a 
1% (0.01) chance (a) that the true proportion is outside this estimated 
interval. A larger allowable error, d, (e.g., 3%) results in a wider 
estimate window. Knowing only that the proportion is somewhere within a 
window of 6% (e.g., between 1 and 7 percent) was too large a window of 
error if the percent of systems having occurrence of the UCM List 
contaminants is less than 3 percent, which may be possible based on 
information from previous unregulated contaminant monitoring. In such a 
situation, it would be difficult to determine whether the percent of 
systems with occurrence was significantly different than zero or some 
small number.
    Additionally, EPA would increase the representative sample size to 
710 to 720 (711 used for calculation purposes here) to ensure that each 
State received an allocation of small systems, using an average 
population served (approximately 70,770) divided into the population of 
each source type and size category within each State, for the 
representative sample. (The example average population of 70,770 is 
close to the average population served by large systems.) EPA would 
also add approximately 80 to 90 systems to the sample size to address 
occurrence at non-transient noncommunity water systems (using the same 
average population to allocate systems), with the total number of 
systems then equaling 790 to 810, rounded to 800. This comparable 
population allocation facilitates assigning the number of systems to 
each State in the representative sample.
    EPA invites public comment on the use of different confidence 
levels and/or allowable error (confidence interval) to determine the 
representative sample size, and the allocation of systems by state, 
water source type and system size using an average population served 
should occur, and if so, why and how. EPA also invites public comment 
on whether and how to allocate proportionally more systems in the 
representative sample to the size category of 25 to 500 persons served, 
which represents only two percent of the total population served by 
community water systems, but includes 64 percent of all community water 
systems. Since these smaller systems vary considerably in location and 
access to a water source, allocating more systems to this category may 
improve EPA's understanding of contaminant occurrence in them.
    Initially, EPA had identified 1,800 to 2,000 systems as the sample 
size for the representative sample. EPA first focused on this sample 
size considering that the percent of contaminant occurrence could be 
any value. In particular, requiring a narrow confidence interval around 
the occurrence level of 50 percent leads to this larger sample size. 
Upon further reflection and analysis of the results of earlier 
unregulated contaminant monitoring, it was realized that EPA's primary 
concern is accurate estimation of low occurrence levels. As a result, 
the sample size was based on requiring a narrow confidence interval 
(0.01) with a high confidence (0.99) for occurrences as low as 1 
percent (p=0.01). This leads to a sample size of 659 systems. As noted 
above, EPA proposes to increase the sample size to 800 to incorporate 
non-transient noncommunity water systems and to have at least 2 sampled 
systems per State. If higher percentages of systems with contaminant 
occurrence are observed, the sample size of 800 systems provides a 
wider confidence interval. For example, if 30 percent of systems having 
occurrence of a contaminant, this sample size results in a confidence 
interval of about 4 percent. Even though the confidence 
interval is relatively wide, the statistics clearly demonstrate a high 
rate of occurrence, and if health data indicated major acute or chronic 
effects for this contaminant, EPA would likely decide to regulate it. 
With small percentages of systems having occurrence (e.g., 1 to 2%), 
EPA believes that the statistical approach of using a 99% confidence 
level and 1% confidence interval will provide sufficient results for 
decisionmaking for the representative sample of small systems. 
Furthermore, when the results are combined with those of the 2,774 
large systems and evaluated using a 99% confidence level and assuming 1 
to 2 percent of systems have occurrence, a confidence interval of 0.4% 
results, allowing EPA to distinguish very low percentages of systems 
with occurrence from a zero percent of systems. This circumstance may 
be important for contaminants with important health effects when 
deciding whether to regulate them. For the example mentioned above, if 
30 percent of systems have occurrence for a contaminant, when the 
results are combined with those of large systems, the resulting 
confidence interval is 2 percent.
    The representative sample of 711 systems will be disaggregated to 
the State level, and further disaggregated by water source type (ground 
water or surface water) and system size (the three size categories of 
25-500, 501-3,300, and 3,301-10,000 persons). The disaggregation by 
State, water source type and system size is described in the following 
example.
    Example. To determine the number of PWSs to be randomly selected 
for unregulated contaminant monitoring as part of the national 
representative sample, the following figures are used as the starting 
point and are approximations for the purposes of example only:

U.S. population: 265,000,000
U.S. population served by small PWSs serving  10,000 
persons: 50,000,000
    U.S. population served by small PWSs divided by 711 (the 
statistically derived number of 659 systems plus 52 systems for the 
national representative sample to allow allocation of systems to each 
State, water source and size category, to the extent possible),

50,000,000/711 = 70,300 persons, the average number or persons that 
each system selected will represent in the allocation to each state in 
the representative sample (i.e., the number that EPA would divide into 
the population served by small systems serving 10,000 or fewer persons 
to determine the number of systems of that size that must be monitored 
in the State)

    State A population served by small PWSs serving 10,000 or fewer 
persons equals 1,251,340 persons, which divided by 70,300 persons from 
the previous step equals 17 systems, the number of systems serving 
10,000 or fewer persons that must be included in the State Plan.

State A population served by small PWSs supplied by surface water (SW) 
or ground water under the direct influence of surface water (GWUDI) 
equals 449,920 persons.
State A population served by small PWSs supplied by ground water (GW) 
equals 801,420 persons.
For each water source type (surface or ground water), the population 
served by small systems is further divided into the size category. The 
next step is to divide the population in each size category by 70,300 
to obtain the number of systems in that size category for the water 
source type that would be in the State Plan (identified

[[Page 23424]]

below as ``State Plan Systems Allocation''). For each water source 
type, the example results for State A are:

                                           SW/GWUDI Systems in State A
----------------------------------------------------------------------------------------------------------------
                                                                                          State plan systems
      System size  (persons served)           Population served  by size category             allocation
----------------------------------------------------------------------------------------------------------------
10,000 to 3,301..........................  281,200 persons..........................  4 systems.
3,300 to 501.............................  154,660 persons..........................  2 systems.
500 or fewer.............................  14,060 persons...........................  0 systems.
                                                                                     ---------------------------
    Total...........................................................................  6 systems.
----------------------------------------------------------------------------------------------------------------


                                              GW Systems in State A
----------------------------------------------------------------------------------------------------------------
                                                                                          State plan systems
      System size  (persons served)           Population served  by size category             allocation
----------------------------------------------------------------------------------------------------------------
10,000 to 3,301..........................  421,800 persons..........................  6 systems.
3,300 to 500.............................  239,020 persons..........................  3 systems.
500 or fewer.............................  140,600 persons..........................  2 systems.
                                                                                     ---------------------------
    Total...........................................................................  11 systems.
----------------------------------------------------------------------------------------------------------------

    The total of 6 surface water and 11 ground water systems equals 17 
systems, the number in State A's Plan. The replacement list of systems 
would also be developed and provided at this level of detail.
    EPA has prepared a background document titled ``National 
Representative Sample and State Plans for Unregulated Contaminant 
Monitoring for Public Water Systems Serving 10,000 or Fewer Persons'' 
to describe in more detail this selection process presented above and 
its relation to the State Plans. EPA requests public comment on this 
proposal and its supporting background document and other approaches 
that EPA could consider. The background document is available today by 
calling the EPA Safe Drinking Water Hotline at (800) 426-4791, or by 
viewing on EPA's Internet Homepage for the Office of Ground Water and 
Drinking Water (www.epa.gov/ogwdw). Public comments on the background 
document should be sent to EPA with the heading ``Representative Sample 
Background Document Comments'' along with comments on this proposed 
rule.
(b) Systems Selected for Pre-Screen Testing
    For Pre-Screen Testing, States would need to specify from 5 up to 
25 systems as being representative of systems most vulnerable to the 
contaminants on List 3. EPA proposes to determine the number of systems 
to be selected in any State based on the number of persons served by 
community and non-transient noncommunity water systems in a State. For 
the systems in this selection that serve 10,000 or fewer persons, EPA 
proposes that the States modify their State Plans at the time of their 
selection and notify the EPA Regional Office of their addition to those 
Plans.
(c) Tribal Water Systems as a Separate Group
    Public water systems serving less than 10,000 persons that are 
located in Indian country would be treated as a single, separate group 
for the representative sample. The random selection process described 
above weights systems within water source and size category by 
population served; as a result, a PWS in Indian country would have the 
same probability of being selected as any other water system. Because 
no State has jurisdiction over such systems, EPA will consult with the 
appropriate tribal government concerning whether any initially selected 
system should be replaced due to merger, closure, or purchase of water 
from another system. The resulting set of systems will be the ``state 
plan'' for Indian country.
(d) ``Index'' Systems
    EPA generally has less information about systems serving 10,000 or 
fewer persons. This lack of information on these systems and their 
operation affects EPA's ability to tailor regulations to systems of 
this size. To provide an improved understanding of small systems, EPA 
proposes to select up to 30 small public water systems as ``index'' 
sites and conduct Assessment Monitoring at these systems during each of 
the five years for which the UCM List and national representative 
sample are established. Index sites would be selected from the systems 
designated in State Monitoring Plans using a random number generator. 
EPA would pay for this monitoring, including provision of sample 
equipment, shipment of samples, testing, and support help to collect 
samples by sending a field technician to each index system to obtain 
the samples. The purpose of this sampling would be to provide quality 
assurance in collection of the samples for the thirty systems, to 
provide information on the temporal variability that may be encountered 
during a monitoring cycle, and enhanced understanding of these systems 
so that their treatment in future regulations would be more reflective 
of the conditions under which they operate. Owners/operators of index 
sites would be required to provide data on well and screen depth (if 
applicable), wells or intakes used at the time of sampling and pumping 
rates for each well or intake at the time of sampling for unregulated 
contaminants for use in characterizing the UCM results without 
monitoring the entire representative sample with this same frequency 
and schedule. EPA or its representative would collect further 
information on precipitation, land use and other environmental factors 
(e.g., soils and geology) to provide the Agency with information on 
other conditions potentially affecting drinking water quality of small 
systems. This ``index'' site monitoring will facilitate extrapolation 
of Assessment Monitoring

[[Page 23425]]

results nationally for systems of this size.
    A description of the selection process for the ``index'' systems 
using a random number generator and their monitoring is presented in 
the background document, noted above, titled ``National Representative 
Sample and State Plans for Unregulated Contaminant Monitoring for 
Public Water Systems Serving 10,000 or Fewer Persons.'' EPA invites 
public comment on this ``index'' system aspect of the proposed UCM 
program described here.
(e) Other State Data
    Any additional sites sampled by States should not be combined with 
those of the EPA approved State Plan for the purpose of computing 
national estimates of contamination. While providing useful information 
for protecting the health of persons using drinking water from these 
sites, these additional sites would bias the results of the nationally 
representative set of systems if included with those systems selected 
using the stated national criteria. However, if the State desired to 
report the results of such monitoring, EPA could receive the data 
through the Safe Drinking Water Information System (SDWIS) for input to 
the NCOD. EPA plans to develop acceptance criteria to allow such data 
to be placed in the NCOD.
6. Regulatory Options
    With respect to the size of the national representative sample, EPA 
needs to balance the number of systems required for validity with the 
cost of paying for the testing. EPA believes that the proposed approach 
balances the number of systems to be tested with the cost and also 
balances a national representative sample with the allowance for State 
plans. The proposed approach also relieves States from having to 
develop the statistical design and specify the systems to be monitored.
    EPA has studied and rejected a second option of a regulation that 
would specify the conditions and criteria under which the States could 
select the systems in their State. Such an option might have included 
criteria such as specific numbers of systems for the State Plan by 
water source type and system size category, operation of a random 
number generator, and the list of systems to be used. From a scientific 
perspective, this would not result in a consistent representative 
sample because implementation of the criteria would likely vary from 
State to State. The value of the resulting estimates would thus be 
jeopardized. This would also be more burdensome for the States.
    A third option which EPA also studied and rejected is to weight 
monitoring based on prior knowledge of contaminant use or occurrence, 
system operation, or other locational information. The concern with 
this approach is the larger number of systems required to provide the 
results. If any prior knowledge of the proportion of conditions in each 
of several categories is known, allotting unequal numbers of samples to 
each category (or ``strata'') can provide the same overall level of 
confidence and allowable error while requiring fewer samples for that 
strata. This is called stratified random sampling. For example, suppose 
VOCs are known to largely occur in ground waters and not surface 
waters. This information can be used to apportion samples unequally 
between ground water and surface water systems such that the overall 
proportion of contamination can be estimated with fewer samples for 
those contaminants. Fewer samples would be needed in surface systems 
where contamination is low because the proportion of contamination does 
not change much.
    Other contaminants such as certain pesticides may occur more 
frequently in surface waters. Using the same design as for VOCs would 
result in very poor estimates of the proportion contaminated because 
few samples would be taken from the conditions where pesticide 
contamination occurs. So ``tailoring'' designs to reduce the number of 
systems needed would result in a different set of systems to be sampled 
for each contaminant group. Some systems would sample for some 
contaminants, but not others. The total number of systems involved in a 
sampling design stratified for different contaminants would be greater 
than for a simpler design, such as the proposal. At this point, not 
enough is known about some contaminants to adequately stratify a 
sample. Reactions to stratified designs have been largely negative at 
Stakeholder meetings. Therefore, one set of representative systems for 
all contaminants is proposed here, even though it is not ``optimal'' 
for any single contaminant.
    Additionally, some pesticides (e.g. diazinon) on Lists 1 and 2 have 
been observed to exceed acute human toxicity levels. Although the 
Agency is proposing a nationwide random survey of small CWS, the Agency 
notes that such a monitoring program may underestimate pesticide 
occurrence because of the non-random spatial nature of pesticide use 
patterns and its relationship to population.
    An alternative approach that could address this potential 
underestimation would be to stratify sampling based on contaminants or 
contaminant groups (e.g., pesticides, volatile organic compounds and 
microorganisms) and to target sampling to areas of high pesticide use 
or expected contaminant occurrence considering available information. 
Sampling could then be targeted to randomly selected systems in the 
expected use or most vulnerable areas. Separate statistical designs 
would need to be developed for each contaminant or contaminant group. 
Such an approach has the downside, however, of eliminating the 
capability of having State and size based stratifications for small 
system sampling. Nevertheless, between the targeted ``upper bound'' 
type samples and the more geographically representative large system 
samples, this approach would provide a more sensitive indicator of the 
potential threat posed by a particular contaminant.
    Public comment is specifically requested on this alternative 
approach to sample site selection.
    Another issue with respect to sampling relates to the timing of 
quarterly samples for surface water supplied systems. Quarterly 
sampling, even with a targeted vulnerable quarter as proposed, may not 
capture periods of peak pesticide occurrence in every case and, 
therefore, may underestimate exposure. An alternative to quarterly 
sampling for surface water supplied systems would be to sample monthly 
in the three most vulnerable months (e.g., May, June and July, as in 
today's proposal) and in one month that is representative of the rest 
of the year. While this approach might provide a more reliable picture 
of pesticide occurrence, it may be incompatible with peak occurrence of 
other contaminants (such as volatile organic compounds) during other 
months of the year. Furthermore, events of an extremely ephemeral 
nature may not be of public health significance. EPA requests public 
comment on the adequacy of the quarterly monitoring approach suggested 
in this rule and the efficacy of alternative approaches considering 
representativeness, implementability and cost. Comment is also 
requested on all aspects relating to the timing and frequency of 
monitoring, system selection, and targeted monitoring relative to 
contaminants.

G. Reporting of Monitoring Results

    Under the current unregulated contaminant monitoring program, 
reporting requirements exist at 40 CFR

[[Page 23426]]

141.35. Today's proposed regulation replaces those requirements to make 
the reported results more useful for sound scientific analyses of the 
occurrence of unregulated contaminants.
1. PWS and State Reporting to EPA
    Unregulated contaminant monitoring data is one of four types of 
data that will potentially be reported to the National Drinking Water 
Contaminant Occurrence Data Base (NCOD) as required by section 1445(g). 
The other types of data that may be included in the NCOD are: (1) 
Regulated Contaminant Occurrence Data below the maximum contaminant 
level (MCL) but above the minimum reporting level (MRL) (a regulation 
may be developed to obtain this data during 1999); (2) source water 
monitoring data; and (3) other data from special studies and research. 
Since these data will come from varying sources, they may have 
different reporting requirements. The PWS data from unregulated 
contaminant monitoring may have the smallest number of data elements to 
be reported because of the greater level of control over the quality of 
the data through the laboratory certification programs and the 
monitoring and quality control requirements proposed today. The uses of 
UCM program data that support the need for the data elements proposed 
today are: (a) Identification contaminants for the Contaminant 
Candidate List, (b) selection of contaminants for future regulation, 
and (c) development of new national primary drinking water regulations 
for the selected contaminants.
    Under the current UCM program, the State Reporting Guidance for 
Unregulated Contaminant Monitoring, EPA-812-B-94-001, August 1994, 
identifies the 12 data elements in Table 8 that should be reported by 
PWSs to States, and by States to EPA, for each unregulated contaminant 
sample test result.

                                  Table 8.--Current UCMR Reporting Requirements
----------------------------------------------------------------------------------------------------------------
               Data Element                                              Definition
----------------------------------------------------------------------------------------------------------------
Public Water System (PWS) Identification    The code used to identify each PWS. The code begins with the
 Number.                                     standard two-character postal State abbreviation; the remaining
                                             seven characters are unique to each PWS.
Sampling Point Identification Number......  An ID number established by the State, or, at the State's
                                             discretion, the PWS, and unique to the system for a sampling point.
                                             Within each PWS, each sampling point must receive a unique ID
                                             number, including entry points to the distribution system as well
                                             as other locations within the public water system, such as
                                             wellhead, intake, or within the distribution system. The same
                                             Sampling Point Identification Number must be used consistently
                                             throughout the history of unregulated contaminant monitoring to
                                             represent the sampling point. NOTE: This data element is proposed
                                             to be combined under ``Water system facility identification
                                             number.''
Sampling Point (Station) Type.............  The water type represented by the sample. The valid choices are:
                                            (a) Finished/treated water.
                                            Note: expanded in this proposal to include:
                                               (i) Finished Water from treatment system.
                                               (ii) Entry Point to the distribution system after treatment.
                                               (iii) Within the Distribution System.
                                               (iv) End of the Distribution line with longest residence time.
                                               (v) Household/drinking water tap.
                                               (vi) Unknown.
                                               (vii) Other.
                                               (b) Raw/untreated water.
Water Source Type.........................  The source type represented by the sample. The valid choices are:
                                            (a) Surface water or purchased surface water. NOTE: Expanded in this
                                             proposal to include: (i) Stream, and (ii) Lake Reservoir.
                                            (b) Ground water under the direct influence of surface water or
                                             purchased Ground water under the direct influence of surface water.
                                            (c) Ground water or purchased ground water.
Sample Identification Number..............  A unique identifier assigned by the PWS for each sample.
Sample Collection Date....................  The date the sample is collected.
Contaminant...............................  The unregulated contaminant for which the sample is being analyzed.
Analytical Results--Sign..................  An alphanumeric value indicating whether the sample analysis result
                                             was:
                                               (a) (<) ``less than'' means the contaminant was not detected or
                                                was detected at a level ``less than'' the MRL.
                                               (b) (=) ``equal to'' means the contaminant was detected at a
                                                level ``equal to'' the value reported in ``Analytical Result--
                                                Value.''
Analytical Result--Value..................  The actual numeric value of the analysis for chemical and
                                             microbiological results.
Analytical Result--Unit of Measure........  The unit of measurement for the analytical results reported. (e.g.,
                                             micrograms per liter, ``g/L; colony-forming units per
                                             milliliter, CFU/mL, etc.)
Analytical Method Number..................  The method number of the analytical method used.
Composite.................................  NOTE: ``Composite'' is on the current UCM Data Element list but is
                                             proposed to be deleted from the future UCM Data Element List
                                             because compositing is not consistent with contaminant occurrence
                                             monitoring.
----------------------------------------------------------------------------------------------------------------

    EPA engaged in an extensive process of stakeholder and technical 
review when developing the NCOD to identify information reporting 
requirements that allow data from different sources to be adequately 
evaluated, compared, and interpreted. The NCOD information requirements 
process has identified additional data elements that must be considered 
for UCM reporting with unregulated contaminant sample test results. 
These data elements are especially important because many of the 
contaminants may not be routinely tested for and will need sample test 
data quality indicators to assist in interpreting the results. These 
additional data elements for the unregulated contaminants, and the 
reasons EPA is proposing to add them to the reporting requirements, are 
explained briefly below. EPA is requesting public comment on these 
additional reporting requirements

[[Page 23427]]

identified in Table 7, Proposed Data Elements for the UCMR.

----------------------------------------------------------------------------------------------------------------
       Proposed data element                       Definition                       Reason for reporting
----------------------------------------------------------------------------------------------------------------
Public Water System Facility         An identification number established   Identify source water, treatment
 Identification Number--Source        by the State, or, at the State's       plant and sampling location for use
 Intake/Well, Treatment Plant and     discretion, the PWS, and unique to     in evaluating contaminant source
 Sampling Station.                    the system for an intake for each      controls in regulation development.
                                      source of water, a treatment plan      The source intake/well
                                      and a sampling station. Within each    identification number can be
                                      PWS, each intake, treatment plant      related to latitude and longitude
                                      and sampling point must receive a      for use in geographic analysis of
                                      unique identification number,          land use, soils, geology and
                                      including, for intake, surface water   precipitation for alternative
                                      intake, ground water well or           treatment and control analysis.
                                      wellfield centroid; and, for           Treatment plant identification
                                      sampling station, entry points to      number can be related to treatment
                                      the distribution system, wellhead      information for that plant to use
                                      (or wellfield), intake, or locations   in analysis of alternative
                                      within the distribution system. The    treatments. Sampling Station
                                      same identification number must be     identification number will allow
                                      used consistently through the          the sample test result to be
                                      history of unregulated contaminant     consistently associated with the
                                      monitoring to represent the            same sample location over time for
                                      facility.                              trend analysis.
Public Water System Facility Type..  The facility type represented by the   Indicates the type of facility
                                      water system facility identification   associated with the water system
                                      number:                                facility identification number to
                                        (i) Intake (for surface water        allow appropriate analysis of the
                                         sources);                           results of each sample being taken
                                        (ii) Well or wellfield (for ground   and tested for alternative
                                         water sources);                     treatment analysis.
                                        (iii) Treatment Plant;
                                        (iv) Sampling Station;
                                        (v) Entry Point to Distribution
                                         System;
                                        (vi) Reservoir;
                                        (vii) Booster Pumping Station; and
                                        (viii) Unknown.
Latitude of the Public Water System  The east-west coordinate of each       Used to indicate location of the
 Facility for Source Intake/Well      source intake, well or wellfield       facility in the watershed to allow
 and Treatment Plant.                 centroid, and treatment plant          analysis of alternative treatments
                                      associated with a sample expressed     and in relation to the population
                                      as decimal degrees.                    being served.
Longitude of the Public Water        The north-south coordinate of each         Do.
 System Facility for Source Intake/   source intake, well or wellfield
 Well and Treatment Plant.            centroid, and treatment plant
                                      associated with a sample expressed
                                      as decimal degrees.
Sample Type........................  The type of sample collected.          Indicates reference field,
                                      Permitted values include:              confirmation, etc. sample type to
                                        (a) Reference Sample--calibration    ensure that the sample test result
                                         or QC samples.                      is used for the appropriate
                                        (b) Field Sample--sample collected   analysis (e.g., contaminant
                                         and submitted for analysis under    concentration trends, sample test
                                         this rule.                          performance, etc.).
                                        (c) Confirmation Sample--a sample
                                         analyzed to confirm an initial
                                         contaminant detection.
                                        (d) Field Blank--reagent water or
                                         other blank matrix placed in a
                                         sample container in the
                                         laboratory and treated as a
                                         sample in all respects, including
                                         shipment to the sampling site,
                                         storage, preservation, and all
                                         analytical procedures.
                                        (e) Equipment Blank--samples
                                         generated by processing reagent
                                         water through the equipment using
                                         the same procedures used in the
                                         field to demonstrate that the
                                         equipment is free from
                                         contamination.
                                        (f) Split Sample--sample divided
                                         into sub-samples submitted to
                                         different laboratories or
                                         analysts for analysis.
Detection Level....................  ``Detection level'' is referring to    Indicates lowest quantifiable
                                      the detection limit applied to both    measurement level applied through
                                      the method and equipment. Detection    the method to the sample to allow
                                      limits are the lowest concentration    comparison with other sample test
                                      of a target contaminant that a given   results.
                                      method or piece of equipment can
                                      reliably ascertain and report as
                                      greater than zero (i.e., Instrument
                                      Detection Limit, Method Detection
                                      Limit, Estimated Detection Limit).
Detection Level Unit of Measure....  The unit of measure to express the     Indicates the reporting unit for the
                                      concentration, count, or other value   detection limit.
                                      of a contaminant level for the
                                      detection level reported.
                                     (e.g., g/L, colony forming
                                      units/mL (CFU/mL), etc.).

[[Page 23428]]

 
Analytical Precision...............  For purposes of the UCMR, Analytical   Indicates variability among
                                      Precision is defined as the relative   laboratory results as measured by
                                      percent difference (RPD) between       testing replicate field or
                                      spiked matrix duplicates. The RPD      duplicate spiked samples, and is a
                                      for the spiked matrix duplicates       key measure of sample test
                                      analyzed in the same batch of          performance.
                                      samples as the analytical result
                                      being reported is to be entered in
                                      this field. Precision is calculated
                                      as Relative Percent Difference (RPD)
                                      between spiked matrix duplicates
                                      using,
                                     RPD=[(X1-X2)/{(X1+X2)/2}] x 100......
Analytical Accuracy................  For purposes of the UCMR accuracy is   Indicates whether test results are
                                      defined as the percent recovery of     within a group of measurements
                                      the contaminant in the spiked matrix   corresponding to the true value of
                                      sample analyzed in the same            the results, and is a key measure
                                      analytical batch as the sample         of sample test performance.
                                      result being reported and calculated
                                      using;
                                     %recovery=[(amt. found in Sp--amt.
                                      found in sample)/amt. spiked] x 100.
Presence/Absence...................  Chemicals: Presence--a response was    Chemicals: Indicates results that do
                                      produced by the analysis (i.e.,        not have a quantifiable value.
                                      greater than or equal to the MDL but   Microbiologicals: Allows measure
                                      less than the minimum reporting        under conditions and for
                                      level)/Absence--no response was        microorganisms that are not able to
                                      produced by the analysis (i.e., less   be counted.
                                      than the MDL)
                                     Microbiologicals: Presence--indicates
                                      a response was produced by the
                                      analysis/Absence--indicates no
                                      response was produced by the
                                      analysis
----------------------------------------------------------------------------------------------------------------

    Note that ``composite'' is proposed to be deleted from the original 
set of data elements since the proposed rule would not allow 
compositing. Since this program is designed to measure actual 
occurrence of contaminants, compositing (the combining of samples from 
several sampling points of a water system) would dilute concentrations 
of contaminants to be measured. Stakeholders supported deletion of 
compositing as contrary to the objective of UCM.
    Also note that ``Public Water System Facility source intake 
identification number'' is currently required to be reported under 
existing reporting requirements for the Safe Drinking Water Information 
System (SDWIS). This proposal would continue this requirement and 
expand it to include treatment plant and sampling station, but the 
definition makes specific that it cannot change over time. EPA is not 
requiring through today's proposal the reporting of treatment data 
(treatment objectives and processes) since these data are already 
required to be reported by January 1, 2000, for all systems. (Safe 
Drinking Water Information System FACT SHEET, Revised Inventory 
Reporting Requirements, June 1998). Additionally, the source of water 
in this case is associated with each sample so that the data can be 
used in evaluating contaminant source controls in a watershed or over 
an aquifer. An alternative would be to report the ``River Reach'' or 
``Aquifer'' for each sample, but that approach would require data to be 
reported that is not currently required, or not readily available, in 
the case of aquifers.
    The rationale for proposing the inclusion of these data elements is 
that EPA needs the detailed information concerning the sample test, 
location, and treatment that would allow the results to be used in 
making a determination of whether or not to regulate the contaminant. 
The specific reasons are identified in Table 9. To avoid duplicative 
and costly resampling efforts, EPA believes that systems should obtain 
and report the most complete information the first time a sample is 
tested.
    The information requirements process for development of the NCOD 
identified technical questions that need to be answered in the 
regulatory process that the UCMR is to support. These data elements are 
associated with these questions. While the list of data elements would 
increase by eight (from 12 to 20) if all the data elements are included 
in today's proposed UCMR (as compared to the existing UCMR), reporting 
them the first time precludes the need to obtain the information 
through another process. Because the 1996 SDWA Amendments expanded the 
determinations and types of analyses that need to be conducted to 
develop a rule, including these data elements is responsive to the new 
regulatory environment in which drinking water regulations must be 
developed.
    Because reporting of locational and treatment data may be one time 
or infrequent, these new data elements will not be a major burden for a 
PWS. The anticipated reporting frequency for the data elements is as 
follows:

       Table 9.--Anticipated Reporting Frequency for Data Elements
------------------------------------------------------------------------
   Current and proposed data element     Proposed frequency of reporting
------------------------------------------------------------------------
Public Water System Identification       With each sample.
 Number.
Public Water System Facility (PWSF)      With each sample.
 Identification Number-Source Intake/
 Well, Treatment Plant, and Sampling
 Station.
Public Water System Facility Type......  One time, associated with PWSF
                                          Identification Number.
Sampling Station Type..................  One time, associated with PWSF
                                          Identification Number for
                                          Sampling Station.
Water Source Type......................  One time, associated with PWSF
                                          Identification Number for
                                          Source Intake.
Sample Identification Number...........  With each sample.
Sample Collection Date.................  With each sample.

[[Page 23429]]

 
Latitude of Water System Facility for    One time, associated with PWSF
 Source Intake/Well and Treatment Plant.  Identification Number for
                                          Source Intake/Well and
                                          Treatment Plant.
Longitude of Water System Facility for   One time, associated with PWSF
 Source Intake/Well and Treatment Plant.  Identification Number for
                                          Source Intake/Well and
                                          Treatment Plant.
Contaminant............................  With each sample (from the
                                          laboratory testing).
Analytical Results--Sign...............  With each sample (from the
                                          laboratory testing).
Analytical Result--Value...............  With each sample (from the
                                          laboratory testing).
Unit of Measure........................  With each sample (from the
                                          laboratory testing).
Analytical Method Number...............  With each sample (from the
                                          laboratory testing).
Sample Type............................  With each sample.
Detection Level........................  With each sample (from the
                                          laboratory testing).
Detection Level Unit of Measure........  With each sample (from the
                                          laboratory testing).
Analytical Precision...................  With each sample (from the
                                          laboratory testing).
Analytical Accuracy....................  With each sample (from the
                                          laboratory testing).
Presence/Absence.......................  With each sample (from the
                                          laboratory testing).
------------------------------------------------------------------------

    Three of the additional nine proposed data elements would be one-
time or infrequently updated information: Water system facility type, 
Latitude and Longitude. These three data elements do not need to be 
reported with each sample once they have been reported by the PWS and 
State to SDWIS. Water system facility identification number-source 
intake/well is already required to be reported to SDWIS under other 
authority. Five of the remaining elements will be supplied by the 
laboratory and the ninth is the sample type identifier (e.g., field 
sample, confirmation sample, spiked sample, etc.).
    Additionally, EPA proposes to require owners/operators of index 
sites that are part of State Plans for the national representative 
sample to provide data concerning well casing and screen depths and 
pumping rates at each well or intake at the time of monitoring. The 
reason for this reporting is that it will allow EPA to tailor 
regulations to systems serving 10,000 or fewer persons by relating 
sample test results to conditions that affect capture of contaminants 
by ground water supplied systems.
2. Regulatory Options
    Following are the four regulatory options EPA considered for data 
elements in the proposed UCMR.
    (a) Use the existing set of twelve UCMR data elements in the new 
rule. EPA studied and rejected this option because it is not responsive 
to the current regulatory needs. With the current data elements, it is 
not possible to evaluate the performance parameters of the test result 
that should be compared to other test results from other laboratories 
or PWSs, at least when considering and reporting detection levels. The 
locational information not in the existing data elements is important 
in conducting exposure assessments and evaluating alternative treatment 
and control measures. Similarly, associating treatment plant 
information with the sample test results is critical in considering 
treatment and control alternatives.
    (b) Add only the sample analysis data elements. This option would 
improve the ability to evaluate and compare the results among 
themselves, but would not facilitate exposure, technical, and 
implementation considerations being addressed in this effort. The 
drawback of this option for contaminants of concern is that additional 
information would need to be obtained through special studies or 
surveys, which can be expensive. This would slow the regulatory process 
for a contaminant that needs to be regulated.
    (c) Add the sample analysis and locational data elements. This 
option would allow better evaluation and comparison of test results and 
facilitate exposure assessments, but not allow treatment evaluations to 
be done.
    (d) Use all the data elements identified above. EPA has selected 
this option because it would allow better evaluation and comparison of 
test results, as well as facilitate exposure assessments and regulation 
development. The capability of associating treatment information with 
sample test results through the Public Water System Facility 
Identification Number would be included in the reporting, with the 
expectation that no or only minor treatment studies targeted to the 
specific contaminants would need to be conducted. The locational 
information (Latitude and Longitude) associated with the Public Water 
System Facility Identification Number for intakes and wells (or 
wellfield centroids) and treatment plants would enable analysis of 
alternatives for treatment and control measures at the facility or in 
the watershed for contaminant best management practices. This option is 
fully responsive to the current regulatory environment.
    Options (a) through (c) were rejected because they would require 
EPA to return to the PWS to obtain additional information necessary to 
meet the objectives of unregulated contaminant monitoring. This second 
action would increase the burden of EPA and the PWS. Attempting to 
associate information with a sample after the original monitoring event 
does not ensure that the correct data is properly obtained and 
associated with the sample, jeopardizing any subsequent analyses.
3. Timing of Reporting
    EPA proposes in this rule in Sec. 141.35(c) that PWSs report to 
States or the primacy agency the monitoring results within ten days of 
their receipt. This proposal is consistent with compliance reporting 
requirements under Sec. 141.31. EPA also proposes that States report 
electronically to the National Drinking Water Contaminant Occurrence 
Database (NCOD) (Sec. 142.15(c)(3)) to be maintained by EPA by the 
quarter following their receipt of the data from PWSs.
4. Method of Reporting
    SDWA section 1445 (a)(2)(D) states that each PWS that conducts 
monitoring of unregulated contaminants must provide the results of the 
monitoring to the primary enforcement authority for the system. Today's 
proposed rule requires electronic reporting by PWSs to States 
(Sec. 141.35(b)) or the primary enforcement authority, and by States to 
EPA (Sec. 142.15(c)(3)). The proposal does allow the primary 
enforcement authority to specify another method for reporting by a PWS. 
Stakeholders

[[Page 23430]]

supported this approach. Note that EPA will pay for the testing and 
laboratory analysis of samples for small systems in State Monitoring 
Plans. Since EPA intends to establish electronic recordkeeping of the 
results from systems in State Plans, electronic reporting for these 
systems would be done through the assistance of EPA. A State might 
consider specifying another method for reporting when a system serving 
over 10,000 persons has not developed the capability to report 
electronic results. However, most laboratories have this capability and 
could probably provide this service for the PWS.
    With respect to electronic reporting by States to EPA, the Agency 
has determined that ninety percent of the States now have the current 
unregulated contaminant monitoring data in electronic format and could 
provide it in that form. Since most States rely on electronic reporting 
to manage the significant amount of data they possess, EPA proposes 
that all States report electronically. EPA will consult with States 
that do not have this capability to determine other options for 
obtaining electronic reports of their data to comply with this proposed 
requirement.
5. Public Notification of Availability of Results
    SDWA section 1445 (a)(2)(E) requires notification of the results of 
the UCMR program to be made available to persons served by the system. 
The results of UCMR monitoring for CWSs will be reported through the 
Consumer Confidence Reports (CCR), pursuant to SDWA section 
1414(c)(4)(B) and the final regulation recently published in the 
Federal Register and, for non-community systems, through the revised 
public notification rule to be proposed in mid-1999. Failure to monitor 
for unregulated contaminants required through the UCMR will also be 
reportable under the public notification rule.
    The results that would be reported through the CCR and public 
notification rules should be based on the same monitoring data that the 
States would receive under the UCMR and would be required to be 
reported to the NCOD. Information in the NCOD will be available to the 
public.
6. Voluntary Reporting
    EPA also requests public comment on establishing a voluntary 
reporting program for contaminants that may be monitored and tested for 
because of local concerns but for which EPA is not requiring monitoring 
or reporting as part of this rule. The reporting requirements for the 
contaminants on the proposed Monitoring List would not apply to 
voluntarily reported data for other unregulated contaminants. However, 
monitoring data related to contaminants of local or State concern and 
not on today's monitoring list could be voluntarily reported to the 
NCOD to assist in determining whether they may be a national problem 
and should be considered for establishing health-based standards 
(maximum contaminant levels) or advisories. EPA may consider providing 
reporting guidance for voluntary reporting of such results. EPA would 
be interested in integrating local and/or State data at the national 
level to see whether perceived local concerns have broader national 
occurrence implications. EPA would comply with the Paperwork Reduction 
Act in collecting such data.
    By August 1999, EPA expects to have the capability to accept such 
additional data and store it in the NCOD. The data in the NCOD database 
will be accessible to the public. The voluntarily reported data on 
contaminants (chemical, microbiological and radiological) would assist 
EPA in determining which contaminants it should be concerned about 
nationally for developing the Contaminant Candidate Lists and UCMR 
Lists in the future. Comments on this proposed voluntary reporting 
program, separately identified as comments on ``Voluntary Reporting of 
Other Unregulated Contaminants,'' may be submitted along with comments 
on today's proposed regulation.

IV. Implementation of Today's Proposal

    The implementation of today's proposed regulation has several 
aspects that will be addressed here in approximate chronological order. 
These steps include the following: setting an effective date; program 
delegation; establishing the laboratory testing program; continued 
research on methods development; determining the national 
representative sample and associated State plans; conducting the 
sampling, analysis, and reporting; and modifying the monitoring list. 
The proposed revised UCMR program is described in Figure 1, ``Proposed 
Unregulated Contaminant Monitoring Approach. Additionally, a critical 
part of this program is funding for the testing of the national 
representative sample of systems serving 10,000 or fewer persons.

BILLING CODE 6560-50-P

[[Page 23431]]

[GRAPHIC] [TIFF OMITTED] TP30AP99.001



BILLING CODE 6560-50-C

[[Page 23432]]

A. Setting an Effective Date

    For eleven of the contaminants on the UCMR Monitoring List proposed 
to be tested under Assessment Monitoring, EPA already has methods for 
testing that are expected to give reliable and reproducible results. 
These methods are widely used with the exception of methods for 
Aeromonas, a microbiological contaminant, in the drinking water 
industry but not necessarily for these contaminants. Testing for these 
contaminants will, along with other information, help EPA determine 
whether or not to regulate these contaminants. Results of the UCMR 
testing should also be available for revising the CCL before the next 
CCL must be issued (February 2003). Therefore, EPA proposes that the 
effective date of the UCMR program be January 1, 2001, sixteen months 
after the expected promulgation of the final rule. This timeframe, 
sixteen months, is necessary for States to make changes in their 
programs to allow the testing to occur and for States to review the 
initial State Monitoring Plans and inform small PWSs of their selection 
and of their responsibilities for monitoring. EPA will also use this 
time to set up its laboratory program for testing samples from small 
systems. Because the contaminants in List 1 to be tested under 
Assessment Monitoring will have analytical methods currently in use 
(several methods for compliance monitoring), this timeframe of 16 
months (in combination with the assistance provided by the methods and 
quality control manual) should be sufficient to allow laboratories 
serving large systems (those providing drinking water to more than 
10,000 persons) adequate time to organize and implement the testing 
program. EPA is taking steps to ensure that methods and quality control 
manual and contaminant occurrence reporting guidances are in place to 
allow the program to be implemented at that time. The requirements for 
small systems and sampling and quality control procedures for all 
systems are specified in Sec. 141.40(a)(3), (4) and (5) and Appendix A. 
Figure 2 describes the proposed timing for the implementation of the 
major components and activities supporting the UCMR program.

BILLING CODE 6560-50-P
[GRAPHIC] [TIFF OMITTED] TP30AP99.002


BILLING CODE 6560-50-C

B. Primacy Program Revision

    The UCMR program has historically been a requirement for State 
assumption of primary enforcement authority (``primacy'') for the PWS 
program under SDWA. Primacy allows a State to be the primary agency for 
administering and enforcing the PWS program in that State. EPA believes 
that today's revision of the UCMR, when final, should also become part 
of a States's primacy program. Therefore, each State that currently has 
PWS primacy will need to address any changes in the existing State 
authorities necessary to implement this revised rule. The procedure for 
revision of State programs is found in 40 CFR 142.12.

C. Implementation in Indian Country

    This proposed rule has several provisions applying to State 
governments; this preamble section is intended to clarify how these 
provisions would apply in Indian country and to request comment on 
EPA's proposed approach. First, with respect to state plans, as 
explained earlier in the section on designation of the representative 
sample, EPA intends to include all small systems in Indian country 
together as a single, separate group. Just as small systems in each 
State will be selected at random for participation in the UCMR, small 
systems located

[[Page 23433]]

anywhere in Indian country will be selected at random. Instead of 
notifying the State and allowing the State to select alternative 
systems due to closure, merger or water purchase, however, EPA will 
contact the appropriate tribal governments to make sure that the 
selected systems have not closed or merged and do not buy water from 
another system. The resulting group of systems will be the ``state 
plan'' for all Indian country. The appropriate EPA regional office will 
notify the selected systems of their UCMR responsibilities.
    Under the proposal, states can also participate in the UCMR by 
specifying ``vulnerable'' systems for pre-screen testing, notifying 
systems of their participation in the monitoring and instructions for 
testing in lieu of EPA, and petitioning EPA for a monitoring waiver for 
large systems. EPA requests comment on whether, and to what extent, 
Indian tribal governments should or want to have these authorities as 
well. EPA could treat Indian tribes as states for purposes of 
implementing these authorities under two separate approaches. First, 
because UCMR is part of the primacy program, tribes that have treatment 
as a state status for PWS primacy would be able to carry out these 
authorities for selected systems under their jurisdiction. Second, EPA 
could amend the treatment as a state regulations to allow tribes to 
have treatment as a state status for purposes of carrying out these 
provisions of the UCMR. Under this second approach, a tribe would not 
need to demonstrate that it qualified for treatment as a state for any 
other purpose (for example, primacy or grant administration) other than 
the UCMR provisions. Because these authorities are so limited, EPA 
doubts that Indian tribes would want to seek treatment as a state for 
these limited purposes and, as a result, believes option 1 to be 
preferable. However, if there is significant interest in obtaining this 
authority apart from primacy, EPA may in the final rule amend the 
treatment as a state regulations (40 CFR 142.72 and 40 CFR 142.78) to 
obtain treatment as a state status solely for the purpose of 
implementing these specific UCMR authorities.
    Finally, the statute allows the governors of seven or more states 
to petition EPA to add contaminants to the UCMR list. EPA requests 
comment on whether Indian tribal governments should or desire to have 
the same authority. EPA believes that for this authority, a tribe that 
has treatment as a state status for either primacy or PWS grant 
administration should be deemed to have treatment as a state for 
purposes of petitioning EPA to add a contaminant to the UCMR list. 
Since the petitioning role is not system specific, a tribe that has 
demonstrated the capability to administer a PWS grant should also have 
the capability to assess whether they believe a contaminant should be 
added to the monitoring list. Therefore, EPA does not expect to make a 
regulatory amendment to the treatment as a state regulations in order 
to allow Indian tribal governments to petition EPA to add contaminants 
to the UCMR list. If EPA decides to treat tribes as states for these 
purposes, EPA would revise the rule language to provide that seven 
governors or tribal leaders could petition EPA to add contaminants to 
the list.

D. Establishing the Laboratory Testing Program

    To ensure that sound data are provided for future regulatory 
decisions, EPA will take three steps in establishing the laboratory 
testing program: (1) Identifying the methods that must be used to test 
for the unregulated contaminants under Assessment Monitoring, (2) 
establishing the laboratory testing program for systems serving more 
than 10,000 persons, and (3) establishing the laboratory testing 
program for systems serving 10,000 or fewer persons.
1. Analytical Methods for the Testing Program
    The methods to be required are identified in Sec. 141.40(a)(3), 
Table 1 of the proposed regulation, List 1, Assessment Monitoring. 
Additional sampling and quality control requirements are identified in 
Sec. 141.40(a)(4) and (5) and Appendix A. EPA has prepared a draft 
sampling guidance, ``UCMR Guidance for Operators of Systems Serving 
10,000 or Fewer Persons,'' which provides additional details on 
sampling requirements. EPA has also produced a draft methods and 
quality control manual, ``Unregulated Contaminant Monitoring Regulation 
Analytical Methods and Quality Control Manual,'' that provides detailed 
guidance regarding specific method requirements related to the 
unregulated contaminants on the Monitoring List. This manual provides 
additional guidance covering quality control steps for all testing 
under this program, as described above in ``Monitoring Requirement 
under the Proposed UCMR.'' These two draft guidance documents are 
available for review and public comment with this proposed regulation. 
Commenters can access the documents through Docket Number W-98-02, 
through the EPA Safe Drinking Water Hotline at 800-426-4791, or through 
the EPA Office of Ground Water and Drinking Water Internet Homepage. 
Today's proposed rule would require that systems serving more than 
10,000 persons follow the methods and procedures in Sec. 141.40(a)(3), 
(4), and (5). The draft methods and quality control manual referred to 
above would provide guidance to these large systems serving more that 
10,000 persons in organizing and conducting their unregulated 
contaminant testing program. EPA will require laboratories that test 
samples of systems serving 10,000 or fewer persons to also comply with 
40 CFR 141.40(a)(3), (4) and (5) and Appendix A.
2. Testing Program for Systems Serving More Than 10,000 Persons
    Implementation of today's proposal would only cause Assessment 
Monitoring of List 1 contaminants. These contaminants have analytical 
methods currently in use and EPA plans to conduct reviews of 
laboratories' procedures for unregulated contaminant testing for 
Assessment Monitoring because of the high data quality requirements of 
this program.
    EPA anticipates that contaminants proposed to be on List 2 for the 
Screening Survey may be monitored during the five-year listing cycle 
through separate rulemaking. Under today's proposal, EPA would 
statistically select approximately 150 large systems that would provide 
samples to laboratories that EPA has approved to conduct this testing. 
EPA's approval of a limited number of laboratories to do this testing 
would include, but may not be limited to, its evaluation of: (1) 
Laboratory capability, (2) test results of blind samples, (3) 
experience with similar methodologies, (4) willingness to accept 
samples from any public water system required to monitor under this 
regulation, and (5) provision of the testing for List 2 (and List 3) 
contaminants at a reasonable price to large systems required to do 
monitoring under this regulation. Large systems selected to be part of 
the Screening Survey (or Pre-Screen Testing for List 3 contaminants) 
will be notified by the State or primacy agency prior to the dates 
established for sample collection and submission for contaminants on 
List 2. EPA requests public comment on options for the testing of List 
2 contaminants of (a) sending samples to laboratories that the Agency 
has approved for testing List 2 and List 3 contaminants or (b) EPA 
providing performance criteria for the testing of List 2 and List 3 
contaminants

[[Page 23434]]

which these systems could use to decide to test at a laboratory of 
their choosing.
3. Testing Program for Systems Serving 10,000 or Fewer Persons
    Based on a competitive selection process, EPA would designate one 
to five laboratories to conduct the testing for systems serving 10,000 
or fewer persons. Under today's proposal, the selected laboratories 
would test Assessment Monitoring samples from the approximately 800 
small systems included in State Monitoring Plans, along with the 
samples from the index systems, over the five-year cycle for the 
program. The laboratories would need to be able to provide all 
necessary sampling equipment to these systems, provide complete yet 
easy-to-follow instructions on use of the sampling equipment, 
coordinate the shipping of the equipment and receipt of the returned 
equipment and samples, provide appropriate sample preservation and 
testing, and report results to the public water systems, States, and 
EPA electronically following the reporting requirements of these 
proposed regulations. EPA will review and evaluate laboratory 
procedures to ensure that sufficient testing and data quality standards 
are met. The requirements proposed today and their supporting draft 
``UCMR Analytical Methods and Quality Control Manual'' would also apply 
to these laboratories as conditions of the planned testing contracts 
that EPA expects to establish with the selected laboratories.
    Once future rulemaking occur to implement the Screening Survey for 
List 2 contaminants, approximately 150 statistically selected small 
systems would provide samples during two to three years in the middle 
of the 5-year cycle. The same laboratories testing List 1 contaminants 
would then also test for List 2 contaminants.

E. Continued Analytical Methods Development

    For the contaminants on the UCM Lists 2 and 3, EPA still needs to 
establish methods that can be widely used at reasonable cost. EPA is 
setting up a research program through its Office of Research and 
Development to identify additional methods. As methods are developed, 
EPA would publish for public comment an amendment to this regulation 
for the contaminants identified previously for the Screening Survey and 
Pre-Screen Testing to specify the analytical methods, sampling 
location, minimum reporting levels applicable to these contaminants, 
and sampling dates.

F. Determining the National Representative Sample and State Monitoring 
Plans

    For systems serving 10,000 or fewer persons, EPA may only require a 
representative sample of such systems to monitor for unregulated 
contaminants in drinking water. Prior to the effective date of the 
program and not later than six months prior to the start of the 
Assessment Monitoring program, EPA would identify, through a 
statistical selection process using a random number generator, up to 
800 systems (from a total of approximately 65,600 community and non-
transient non-community water systems) serving 10,000 or fewer persons 
that must monitor and up to 800 alternate systems if replacements are 
needed. The selection process would allocate systems to each State, 
giving approximately equal probability to each person's water system 
being selected within water source type (ground water or surface water) 
and system size category (25 to 500 persons served, 501 to 3,300 
persons, and 3,301 to 10,000 persons). Based on the appropriate number 
of systems in each State, Tribe or territory (identified by water 
source type and system size category), EPA would send these first 
system selections (i.e., the initial State Plan) and the replacement 
list of alternate systems to each State, Tribe, and territory, as 
appropriate.
    The State, Tribe or territory would have 60 days to review the 
initial plan and (1) accept the initial plan as its State Monitoring 
Plan and inform the Regional Administrator of its acceptance of the 
initial plan along with its process for informing the selected systems 
of their responsibilities for monitoring; (2) propose deletions from 
and alternates to the initial plan as its State plan, including the 
reasons for the changes and the process it would use to inform the 
systems of their responsibilities, and inform the Regional 
Administrator of its proposal; or (3) take no action within 60 days 
allowing the Regional Administrator, after consulting with the State, 
to specify the final State plan. If a State, Tribe, or territory 
chooses option (1) or option (2) above, it must submit a description of 
the process it would use for informing the systems selected of their 
responsibilities for monitoring, when the process would be implemented, 
and any necessary modifications to the timing of sampling for each to 
coordinate with compliance monitoring at the State's discretion. 
However, a State that chooses no action in the initial plan may still 
choose to notify selected systems and provide the necessary 
information. States may also choose an alternate most vulnerable time 
for systems to sample if different from May through July, as proposed 
in the rule.
    The PWSs which EPA selects through the use of a random number 
generator to be index sites would also be specified in the initial plan 
that EPA gives to the State. The replacement list for the initial plan 
would also be applied for the index sites that needed to be replaced. 
EPA expects to provide contractor support through the laboratories 
selected to conduct the testing for unregulated contaminants to 
collect, ship and test the samples and gather the additional data to 
support these ``index'' systems. EPA's procedure for selecting these 
index sites is described in a technical document titled ``National 
Representative Sample and State Plans for Unregulated Contaminant 
Monitoring at Public Water Systems Serving 10,000 or Fewer Persons.'' 
This document can be accessed through Docket Number W-98-02, through 
the EPA Safe Drinking Water Hotline at 800-426-4791, or through the EPA 
Office of Ground Water and Drinking Water Internet Homepage at 
www.epa.gov/ogwdw. EPA requests comment on the selection procedure 
detailed above and in this document.
    While monitoring for List 2 contaminants under the Screening Survey 
is not proposed by today's action and would not be implemented until a 
new rulemaking activated these contaminants for monitoring, EPA 
proposes that EPA provide with the State Plans a list of systems that 
would conduct monitoring for List 2 contaminants. EPA believes that the 
methods for the contaminants on List 2 will be ready for use during the 
first three years of the five year listing cycle and that the Screening 
Survey will be implemented during that time. EPA would select 
approximately 300 systems (approximately 150 large and 150 small 
systems) using a random number generator to specify them at the same 
time that EPA prepares the initial plan described above. If this survey 
list was not sent at the same time of the initial State Plan, then EPA 
would have to provide a second list to each State to implement the 
Screening Survey. EPA believes that the preparation of a second list is 
unnecessary. The EPA specification and State review of the Survey list 
can occur at the same time.
    For Pre-Screen Testing, States would need to specify from 5 up to 
25 systems as being representative of systems most vulnerable to the 
contaminants on List 3. The number of systems to be selected in any 
State would be determined by

[[Page 23435]]

EPA based on the number of persons served by community and non-
transient noncommunity water systems in a State. For the systems in 
this selection that serve 10,000 or fewer persons, States would modify 
their State Plans at the time of their selection and notify the EPA 
Regional Office of their addition to those Plans.

G. Specifying the Vulnerable Monitoring Period

    The State may modify the vulnerable monitoring period specified in 
Sec. 141.40(5)(ii)(B) applicable to all monitored systems. The State 
may consider environmental, precipitation, and system factors in 
changing this vulnerable period. The vulnerable monitoring period may 
be changed for a single system, a subset of systems or all monitored 
systems.

H. Conducting the Sampling

(1) All Monitored Systems
    All monitored systems must sample for the unregulated contaminants 
identified on the Monitoring List 1 and should coordinate, at State 
discretion and to the extent practical, with their compliance 
monitoring schedule for regulated chemicals. For chemical contaminants, 
surface water-supplied systems must monitor every three months during a 
twelve-month period and ground water-supplied systems, two times six 
months apart in a twelve-month period of the years indicated in column 
6 of UCMR Table 1, List 1, Sec. 141.40(a)(3), of every five-year 
listing cycle. One sample at each entry point to the distribution 
system after any treatment representing all water sources in use during 
the twelve-month period or at each distribution system sampling point 
must be taken during the May-June-July time of the monitoring period, 
unless the State identifies a more vulnerable time for a particular 
system, subset of systems, or all monitored systems in the State. In 
sampling microbiological contaminants, the PWS must monitor at a site 
in the distribution system representative of the water supplied to the 
system's service area and at a site near the end of the distribution 
line with the longest residence time. One sampling event must occur at 
the most vulnerable time for the system, proposed as May 1 through July 
31, or another time designated by the State as the most vulnerable 
period, and six months later.
    In preparing this proposed regulation, EPA sought input of 
stakeholders on the timing of the monitoring cycle. Their input 
indicated that most States are on a three-year compliance monitoring 
schedule, with approximately one third of the systems being monitored 
each year. EPA proposes to use this same schedule for unregulated 
contaminant monitoring. The five-year unregulated contaminant listing 
cycle can be coordinated with the three-year compliance monitoring 
schedule by starting the next five year monitoring round in January 
2001 and taking the samples with any compliance sampling being done, 
regardless of where the three-year cycle is in a particular State. 
Sampling in the remainder of the State would be done in the next two 
years, following the State's compliance monitoring schedule. This 
proposal means that a system may not be sampling for regulated 
contaminants during the 5-year listing cycle and may be required to 
conduct unregulated contaminant monitoring during that time.
(2) Systems Serving More Than 10,000 Persons
    For Assessment Monitoring, systems serving more that 10,000 persons 
would follow the sampling requirements in Sec. 141.40. These 
requirements are explained further in the draft methods and quality 
control manual.
(3) Systems in State Monitoring Plans
    EPA has drafted guidance, ``UCMR Guidance for Operators of Public 
Water Systems Serving Less Than 10,000 People,'' on the 
responsibilities of the PWSs that are part of the representative sample 
and State Plans. This guidance further explains the requirements for 
operators of small systems proposed at Sec. 141.40(a)(3), (4) and (5) 
and appendix A. This guidance addresses sampling instructions including 
frequency and location, receipt and use of sample equipment, sample 
shipping to laboratories, review of results, and reporting. States can 
use the guidance to give schedules and instructions to the systems as 
part of informing them of their responsibilities to participate in the 
representative sample and State plan. The draft guidance is available 
for public comment with this rule. Commenters can access the draft 
document through Docket Number W-98-02, through the EPA Safe Drinking 
Water Hotline at 800-426-4791, or through the EPA Office of Ground 
Water and Drinking Water Internet Homepage at www.epa.gov/ogwdw.
    Systems serving 10,000 or fewer persons that are part of the 
State's representative sample plan must sample at the locations 
identified in the regulation, similar to the other systems described 
above. EPA would inform the competitively selected laboratories as to 
which systems are included in State Monitoring Plans and should, 
therefore, receive sampling equipment.
    A statistically selected subset (ten percent) of systems in State 
Monitoring Plans would be required to collect duplicate samples for 
quality control purposes. These systems would follow the same 
procedures as for the first sample collection.

I. Screening Survey

    The Screening Survey is not part of today's proposal, except to 
publish the List 2 contaminants that may be part of the Screening 
Survey as part of the EPA revised Unregulated Contaminant Monitoring 
List. When EPA develops methods for groups of contaminants on 
Monitoring List 2 for the Screening Survey, the Agency will by rule, 
after peer review of the analytical methods, require that samples for 
the List 2 contaminants be collected and submitted by small and large 
systems for testing. The rule would include a list of which 
contaminants PWSs would need to submit samples for the Screening 
Survey. EPA will pay for sample shipping and testing for systems 
serving 10,000 or fewer persons.

J. Pre-Screen Testing

    Pre-Screen Testing is not part of today's proposal, except to 
publish the List 3 contaminants as part of revised UCM List. Pre-Screen 
Testing of List 3 contaminants would be implemented after EPA 
promulgates a rule, after peer review of the analytical methods, 
specifying the analytical methods, minimum reporting levels, and sample 
locations and dates for those contaminants. Pre-Screen Testing would be 
a limited sampling and testing activity, conducted under highly 
controlled conditions. The EPA Regional Office would send a letter to 
the State requesting the identification of the vulnerable systems for 
Pre-Screen Testing. The State would need to submit its selection of 
vulnerable systems within 60 days of receiving the EPA letter. States 
would identify, based on the population served by community water 
systems in the State and the vulnerability of the systems to the 
contaminant, 5 to 25 large and small systems that they determine to be 
most vulnerable to the contaminants specified from List 3 in order to 
identify a national set of up to 200 systems that may be sampled under 
Pre-Screen Testing. EPA wants to clarify that Pre-Screen Testing would 
only be representative of the most vulnerable systems and not of all 
systems in the nation. EPA intends to use these results to determine 
whether a more

[[Page 23436]]

representative monitoring effort should occur through Assessment 
Monitoring or a Screening Survey, not to generate a national occurrence 
estimate. However, EPA could elect to proceed directly to a 
determination to regulate one or more of these contaminants in the 
event of a clear and present public health threat, based on all 
available information.
    For sampling contaminants that require specific training and skills 
to ensure the sample integrity, EPA may contract for the sampling, only 
requiring the PWS owner/operator to provide access to the sampling 
locations. EPA would pay for sample shipping and testing for the small 
and medium systems participating in Pre-Screening Testing, and would 
report the results to the PWS and State for review before allowing 
public access through the NCOD. Large systems would pay for the 
sampling, sample shipping and testing of these contaminants at EPA 
approved laboratories and report the results to the State for review 
and submission to the NCOD.

K. Testing

    As discussed above, EPA has prepared a draft methods and quality 
control manual for the sampling and testing of the contaminants on the 
monitoring list that would, after public comment, be distributed to 
States and made generally available. This manual provides guidance on 
the requirements proposed in Sec. 141.40(a)(3), (4) and (5) and 
appendix A. Laboratories that are conducting testing for these 
contaminants at the request of the public water systems would need to 
follow the requirements in Sec. 141.40, Appendix A and the methods in 
the manual. EPA expects to set up a program to review methods 
implementation and performance of the participating laboratories.
    For public water systems serving 10,000 or fewer persons that are 
included in State Plans, EPA would identify from one to five 
laboratories through a competitive process that would test for 
unregulated contaminants for this category of systems. EPA is doing 
this so it can pay the testing costs for small systems. EPA intends to 
issue a ``request for bids'' in 1999 for laboratories that desire to be 
considered for selection as one of the laboratories which will test the 
unregulated contaminant samples from these small systems. The first 
samples are expected to be available for testing after January 1, 2001.

L. Reporting Requirements

    The results of the testing of any sample under the unregulated 
contaminant monitoring program would need to be reported along with the 
20 data elements identified in the proposed regulation. EPA proposes 
that PWSs report electronically to States, unless the State, or EPA if 
the State does not have enforcement authority, specifies alternative 
reporting requirements. EPA also proposes that States report these 
results to EPA electronically. EPA encourages all laboratories that 
perform unregulated contaminant testing for public water systems to 
report results electronically. Under today's proposal, small PWSs 
included in State Plans will need to report the first nine data 
elements: PWS identification number; public water system facility 
identification number for source intake/well, treatment plant and 
sampling station; sampling station type; water source type; sample 
identification number; sample collection date; latitude of public water 
system facility for source intake/well, and treatment plant; and 
longitude of public water system facility for source intake/well and 
treatment plant to the EPA laboratory conducting the testing. The 
remaining data elements must be reported to the PWS by the laboratory. 
The State or EPA Regional Office may identify another reporting method 
for public water systems within its supervision, such as a standard 
hard copy or paper format that could be electronically scanned to put 
the data into an electronic format for computer storage, retrieval, and 
use. EPA requests public comment on alternative ways to report these 
data, instead of reporting electronically. EPA intends to provide 
States reporting guidance in ``Unregulated Contaminant Monitoring 
Reporting Guidance,'' that may include a standard hard copy format that 
systems could use if the State or EPA Regional Office waives the 
requirement to report electronically. This draft guidance is available 
for public comment through Docket Number W-98-02, through the EPA Safe 
Drinking Water Hotline at 800-426-4791, or through the EPA Office of 
Ground Water and Drinking Water Internet Homepage at www.epa.gov/ogwdw. 
States would be able to report unregulated contaminant data 
electronically to the EPA Safe Drinking Water Information System 
(SDWIS). SDWIS would have a storage area for the National Contaminant 
Occurrence Database (NCOD) to which unregulated contaminant data would 
be routed electronically.

M. Record Keeping

    The PWS and the State would continue to have responsibilities for 
record keeping for the data from unregulated contaminant monitoring as 
currently required under Sec. 141.33 for the PWS and Sec. 142.14(a) for 
the State.

N. Modifying the Monitoring List

    As required in Section 1445, every five years, EPA will modify 
today's proposed Table 1, Unregulated Contaminant Monitoring List, to 
include contaminants of greatest concern at that time. If EPA still 
requires additional data for some previously listed contaminants, those 
contaminants may remain on the list. As discussed previously, EPA is 
requesting public comment on maintaining a monitoring list with more 
than 30 contaminants, but only requiring monitoring for 30 contaminants 
within a particular five-year contaminant listing cycle.
    States can also request a change to the Monitoring List through 
petition by seven or more governors. Their petition must clearly show 
that the proposed contaminant should be considered a greater health 
concern than other contaminants on the Monitoring List. The petition 
should also provide any available information on known or expected 
occurrence of the contaminant in drinking water, analytical methods 
that are or could be used to test for the contaminant(s) and other 
information that would assist EPA in determining whether the 
contaminant(s) should be added to the List. The EPA Administrator would 
make a determination as to whether the contaminant proposed is of 
greater health concern to warrant putting it on the Monitoring List in 
place of another contaminant.

O. Funding for Testing of Samples for Systems in State Monitoring Plans 
and for Pre-Screen Testing

    EPA will pay for small system costs of sample testing. Grants to 
pay for a system's sample testing can only be made for monitoring costs 
that are incurred pursuant to a State Monitoring Plan. EPA considers 
the public water systems serving 10,000 or fewer persons included in 
State Plans as the grantee (recipient of the grant). The Agency can 
contract to establish the necessary laboratory testing capability, then 
grant the laboratory's services to the public water systems. EPA 
proposes to make payments to a laboratory, several laboratories, or 
other testing organizations to conduct the testing and make a grant of 
their service to these systems. However, because these funds

[[Page 23437]]

are authorized within the context of a State Monitoring Plan, any 
payments to another entity for this testing service would have to be 
limited to small systems included in final State Plans. To achieve 
reliability, quality control and consistency of the testing, EPA would 
specify that samples produced under the State plan must be submitted to 
a laboratory that meets the requirements in Sec. 141.40(a)(3), (4) and 
(5) and appendix A, and further described in the methods and quality 
control manual, and has been approved for this work by the Agency. EPA 
expects to save up to $2 million per year as compared to the current 
UCM program through this testing program.
    There are two authorizations for funding to carry out SDWA section 
1445(a)(2)(C), both of which could be used for testing costs of a State 
Monitoring Plan for small systems if appropriations are provided. 
Beginning in fiscal year 1998, the Agency is required to reserve $2 
million each year from funds appropriated under SDWA section 1452 
Drinking Water State Revolving Loan Fund set-aside to pay for the costs 
of unregulated contaminant testing. Section 1445(a)(2)(H) authorizes 
$10 million annually through fiscal year 2003 to carry out all the 
purposes of the unregulated contaminant monitoring program. This could 
also include paying for the costs of testing for small systems under 
State monitoring plans. At this time, $2 million from the set-aside of 
the Drinking Water State Revolving Fund appropriation for FY 1998 and 
for FY 1999 are available to be spent to support unregulated 
contaminant monitoring for small systems. EPA will continue to use this 
set-aside from the Drinking Water SRF appropriation under SDWA in 
future budget years to cover the costs of this testing, as well as 
small system testing under the Screening Survey and Pre-Screen Testing. 
Should funding levels change for the UCM program, EPA would need to 
consider how to accommodate reduced funding. In this event, for 
example, EPA could recalculate the representative sample size to a 
lower confidence level, commensurate with available resources.
    Funding for the monitoring approach described previously is as 
follows:
    (1) Assessment Monitoring--EPA will pay for the sample equipment 
and shipping, testing, and electronic reporting for systems serving 
10,000 or fewer persons. Systems serving more than 10,000 persons would 
need to pay for their own sample equipment and shipping, testing, and 
electronic reporting.
    (2) Screening Survey--Since the methods in a Screening Survey may 
not have been evaluated on a multi-laboratory basis but the results 
would be a representative survey of contaminant occurrence and be 
consistent with the approach of Assessment Monitoring, large systems 
would need to pay for testing at a laboratory that EPA has approved for 
testing the contaminants on List 2. These methods will be peer reviewed 
to ensure that they can perform adequately before EPA proposes a rule 
to implement the Screening Survey.
    Funding options within the water industry for the Screening Survey 
may be possible and would need to be considered by the industry itself. 
EPA would only pay the costs of sample collection, shipping and testing 
samples from systems serving 10,000 or fewer persons .
    (3) Pre-Screen Testing--EPA proposes to pay for the sample 
collection and testing for small systems only. Large systems would pay 
for the costs of testing for List 3 contaminants at a laboratory that 
EPA has approved for testing these contaminants.

V. Relation of the Proposed Regulation to the Existing Regulation

    Under a separate action, EPA published a Direct Final Rule on 
January 8, 1999, which will suspend the existing monitoring 
requirements for systems serving 10,000 or fewer persons only, 
beginning January 1, 1999, and until the requirements in this proposed 
rule are effective. This action modifies the existing regulation ahead 
of the promulgation and implementation of the proposed unregulated 
contaminant monitoring rule. The Direct Final Rule's purpose is to 
allow the systems serving 10,000 or fewer persons to save the cost of a 
third monitoring round under the existing regulation, which if 
performed would overlap with monitoring under the proposed revised 
rule. Today's proposed regulation revisions will entirely replace the 
existing sections of the Code of Federal Regulations at 40 CFR 141.35, 
141.40, and 142.15(c)(3), and modify 142.16. The large systems should 
already have completed their third round of monitoring, and their 
fourth round is not due to begin until this rule has been promulgated.

VI. Cost and Benefit of a Revised UCMR Program

A. Program Cost Estimates

    Today's proposed regulation would only require that Assessment 
Monitoring for List 1 contaminants be conducted. The contaminants on 
Lists 2 and 3 would not be monitored until EPA promulgates rules to 
activate the monitoring for those contaminants. EPA has estimated the 
costs of complying with the requirements of the new unregulated 
contaminant monitoring program (including the List 1, List 2 and List 3 
components) in terms of labor costs and non-labor costs. Labor costs 
pertain to systems, State/Primacy Agencies, and EPA, and include 
activities such as reading the regulation, notification, sample 
collection (e.g., at entry points or distribution system sites), 
reporting, record keeping, and analysis of data. Non-labor costs are 
primarily incurred by EPA and systems serving more than 10,000 people, 
and include costs for shipping these samples to laboratories and the 
sample testing. The Agency will also incur non-labor costs to procure 
services to conduct quality assurance surveys at contract laboratories 
and to collect samples at a select number of Index systems (and at 
small systems selected for Pre-Screen Testing if the full program is 
implemented). Some of these costs are initial program startup costs 
which may not need to be replicated in future monitoring cycles.
    The details of the cost estimates and their assumptions are 
presented in the Information Collection Request (ICR) document (ICR No. 
1882.01). The ICR document presents estimated costs and burdens for the 
1999-2001 period. In addition, a background cost document, titled 
``Burden and Cost Calculations for the Unregulated Contaminant 
Monitoring Regulation'' is attached as an appendix to the ICR, and 
presents the estimated costs and burdens for the first five-year cycle 
of the proposed rule. Copies may be obtained from Sandy Farmer by mail 
at: OP Regulatory Information Division, U.S. Environmental Protection 
Agency (2137), 401 M St., SW; Washington, DC 20460, by email at: 
[email protected], or by calling: (202) 260-2740. A copy may 
also be downloaded off the Internet at: 
http://www.epa.gov/icr.
    While this proposed regulation would initially only require 
Assessment Monitoring, the cost estimates presented assume 
implementation of the full UCMR program. Full program cost estimates 
assume the Assessment Monitoring program will be supplemented by two 
one-year Screening Surveys and a more limited one-year Pre-Screen 
Testing program.
    The Assessment Monitoring would be conducted for List 1 
contaminants, which include 10 chemicals (i.e., all chemicals in List 1 
in the Preamble) and one microbiological contaminant,

[[Page 23438]]

Aeromonas. The Assessment Monitoring would be performed over a three-
year period and would be conducted by all 2,774 systems serving greater 
than 10,000 people and by the nationally representative sample of 800 
systems serving 10,000 or fewer people.
    Once regulations regarding the Screening Survey (List 2 
contaminants) are promulgated, two Screening Surveys would be performed 
to monitor for the List 2 chemical contaminants specified in the UCMR 
regulations. The first Screening Survey would monitor for the List 2 
contaminants for which preliminary sampling and analytical methods are 
now identified; the second Screening Survey would monitor the remaining 
List 2 chemicals (assuming suitable methods are available). Each 
Screening Survey would be conducted for one year and would include a 
separate representative sample of up to 300 public water systems 
selected from systems of all sizes. The two samples of 300 systems 
would be a subset of the systems conducting Assessment Monitoring. The 
Assessment Monitoring, together with the Screening Surveys, would 
provide information on the occurrence of all 24 chemical contaminants 
and one microbiological contaminant on the UCMR list.
    The Pre-Screen Testing would be a smaller component of the UCMR 
program that will gather occurrence data and assess the viability of 
monitoring for at least three List 3 microbiological contaminants: 
Cyanobacteria (blue-green algae, other freshwater algae and their 
toxins), Coxsakieviruses, and Echoviruses. This monitoring would be 
conducted at a targeted sample of up to 200 systems identified as the 
most vulnerable to these microbiological contaminants. Again, these 
systems would be a subset of the systems conducting Assessment 
Monitoring. These systems would be identified as vulnerable by the 
States from all large and small systems (CWS and NTNCWS) in each State. 
From this listing, EPA would randomly select up to 200 systems to 
implement Pre-Screen Testing. It is estimated that this will be 
comprised of approximately 150 small systems and 50 large systems. As 
noted, EPA cannot pre-determine which of the most vulnerable small 
systems will coincide with those 800 systems selected for the national 
representative sample for Assessment Monitoring and Screening Surveys. 
Hence, it is possible that up to 150 additional small systems (for a 
total of 950) could be involved in the full implementation of the UCMR, 
if no Pre-Screen Testing systems came from the national sample selected 
for Assessment Monitoring. However, this situation is unlikely. For the 
cost and burden estimates discussed here and in Section VIII 
(Administrative Requirements), EPA assumes that only 800 small systems 
are included. The number of small Pre-Screen Testing systems does not 
affect the total cost estimates, but does affect some critical 
estimates of the cost and burden per system. Assuming only 800 systems 
presents a conservative, or worst-case, estimate because it evaluates 
the maximum total costs divided across a smaller number of systems.
    Because existing sampling and analytical methods for the List 3 
contaminants are problematic, all sampling at small systems would be 
done by EPA contractors, and all analyses will be performed at EPA 
selected laboratories. The sampling would be done during a one-year 
period, likely year four of the 5-year UCMR cycle. Large systems 
selected to conduct Pre-Screen Testing will be responsible for their 
own sample collection and for the costs of testing at an EPA approved 
laboratory.
    Assessment Monitoring tasks and activities for monitoring chemicals 
contaminants follow proposal outlines: surface water systems would 
sample four times during one year and ground water systems would sample 
two times during one year in the UCMR cycle; EPA would pay for the 
testing costs (analytical services, shipping, etc.) for the 
representative sample of small systems, and these analyses would be 
performed by selected laboratories; large systems, serving more than 
10,000 people, would pay for their own testing, using the laboratories 
of their choice (following UCMR quality control requirements), and; all 
systems would, to the extent practical, conduct their chemical sampling 
coincident with their standard compliance monitoring framework (SMF) to 
reduce labor burden and analytical costs where possible. The program 
would also include various quality assurance and quality control 
measures (e.g., ten percent duplicate samples from the representative 
systems). Aeromonas (a microbiological contaminant) would be sampled by 
both ground and surface water systems at a frequency of two times in 
the year of sampling, at two points in the distribution system. 
Additionally, a subset of 30 small systems, referred to as ``Index 
Systems'', would be sampled during all five years to assess any 
temporal occurrence trends, other data variability, or program 
problems.
    Required monitoring frequencies and burden assumptions for the 
Screening Surveys are the same as those for Assessment Monitoring. 
Under Pre-Screen Testing, EPA contractors will conduct the sampling at 
each targeted small system twice during one year, at a maximum of four 
sampling points per system. Large systems will be required to follow 
the same monitoring schedule.
    Standard assumptions and sources of information were utilized, 
which are the same as those used in other drinking water program ICR 
analyses, and include: public water system inventory, number of entry 
points, and labor rates. For State and some system activities, the 
labor burden was estimated using EPA's standard State Resource Model, 
which is documented in the Resource Analysis Computer Program for State 
Drinking Water Agencies (January 1993).
    Analytical/laboratory services comprise approximately 80 percent of 
the national costs for a program such as the UCMR. These costs are 
generally calculated as follows: The number of systems multiplied by 
the number of entry or sampling points, multiplied by the sampling 
frequency, and multiplied by the analytical cost. (This calculation is 
repeated for each separate analytical method). Shipping costs are added 
to the calculated analytical/laboratory costs to derive the total 
direct analytical non-labor costs. Instead of assuming that large 
systems will pay the full analytical cost for Assessment Monitoring, 
systems are assumed to pay a smaller ``incremental'' analytical costs 
given UCMR monitoring coinciding with ongoing Phase II/V compliance 
monitoring. In some cases, UCMR analyses utilize the same laboratory 
analytical methods that are required for ongoing compliance monitoring. 
Therefore, when UCMR monitoring and Phase II/V monitoring are conducted 
concurrently, only incremental fees are charged for analysis of the 
additional UCMR compounds. With methods that are not currently in use, 
no cost savings can be realized. The full spectrum of assumptions are 
documented in the Information Collection Request, as noted.
    The costs are averaged to an annual basis for the five-year UCMR 
cycle of 2001-2005. With this revised rule, the States and EPA would 
have some one-time start-up costs. Although start-up costs might be 
incurred before 2001, these costs are included and averaged as part of 
the five-year (2001-2005) program costs to simplify calculations. 
Systems will only incur costs during the five-year monitoring cycle. 
Full program (Assessment Monitoring, Screening Survey and Pre-Screen 
Testing) cost estimates appear first below. Following the full program 
costs are the costs for

[[Page 23439]]

Assessment Monitoring alone, which is the focus of this proposed rule.
    Full Program. The Agency estimates that the average annual labor 
and non-labor costs associated with the required unregulated monitoring 
(with the assumptions noted above) are: EPA--$4.0 million, $3.0 million 
of which is for testing costs of the national representative sample and 
contractor site visits to Index and Pre-Screen Testing systems; 
States--$461,500; Systems serving 10,000 or fewer people (from the 
representative sample)--$19,860; all 2,774 systems serving greater than 
10,000--$5.6 million. The total national average annual cost is 
approximately $10.1 million. Estimated average annual costs (labor plus 
non-labor) per system for systems serving 10,000 or fewer are 
approximately $25, and for systems serving more than 10,000 people are 
$2,000 per system.
    Assessment Monitoring. EPA estimates that the average annual labor 
and non-labor costs of Assessment Monitoring for the 11 contaminants on 
List 1 are: EPA--$3.1 million, with $2.1 million for testing costs for 
the national representative sample; States--$461,500; Systems serving 
10,000 or fewer people --$17,340; Systems serving greater than 10,000 
persons--$4.8 million. The total national average annual cost, on this 
basis, is approximately $8.4 million. Average annual costs per system 
for systems serving 10,000 or fewer are approximately $22 per system 
and for systems serving greater than 10,000 persons are $1,730 per 
system. (Note that the total State cost is the same in the Assessment 
Monitoring program as it is in the Full Program. There would be some 
cost reductions to the States if no Screening Surveys or Pre-Screen 
Testing were conducted. However, these reductions would be minor since 
the majority of State UCMR activities will be necessary under the 
Assessment Monitoring component of the UCMR program. With Screening 
Survey and Pre-Screen Testing activities, States will need to manage 
some data additional to that generated by Assessment Monitoring 
activities. EPA estimates that, at most, Screening Survey and Pre-
Screen Testing will account for 10 to 15 percent of State program 
costs. Thus, this estimate for the State Assessment Monitoring cost is 
conservative.)
    Averaging costs over the entire cycle is not necessarily 
representative of peak costs, however. The majority of monitoring (and 
thus cost) is assumed to occur over a three-year time frame, allowing 
for follow-up work, data review, reporting and analysis. EPA peak year 
costs (e.g., during the 3 core years of Assessment Monitoring, 
primarily for the representative sample) are projected to be $4.7 
million per year for the full program and $3.7 million for Assessment 
Monitoring only. Systems serving over 10,000 persons are projected to 
have peak year costs of about $9.5 million for the full program and 
$8.0 million for Assessment Monitoring only.

B. Net Costs

    The net costs of the revised program were estimated by comparing 
the new program costs (stated above) with estimated costs for the 
existing program (baseline). The standard labor rates and activities 
that were used above were also used for estimating the burden of the 
existing program. For comparative purposes, the same water system 
inventory numbers were used. Complete UCMR program implementation was 
assumed. As a simplifying assumption, all systems serving over 500 
people were assumed to conduct the monitoring during the same five-year 
interval. The existing regulation did not require systems serving 150 
or fewer service connections to monitor for unregulated contaminants 
unless requested to do so by the State. Data in the unregulated 
contaminant monitoring information system suggest that States required 
about one third of systems serving 500 or fewer people to monitor; 
thus, one-third were included in the estimates. The other significant 
difference is in the list of contaminants.
    The existing regulation requires monitoring of the 48 chemicals 
included in Table 1 of the Preamble. (While 14 of the chemicals in 
Table 1 were discretionary and not always included in the monitoring, 
their associated costs are derived from the same analytical method as 
required for the other unregulated contaminants and the regulated VOCs. 
Hence, they do not make a substantive difference in the cost 
estimates.) While there are more contaminants analyzed under the 
existing rule than under the proposed UCMR, monitoring requirements for 
the existing UCM program are derived from fewer analytical methods, and 
all are derived from standard methods used for routine compliance 
samples.
    The proposed UCMR compared to the existing UCM Program--given the 
above assumptions and a full proposed UCMR implementation over five 
years--results in an estimated $35.8 million in savings to systems 
serving 10,000 or fewer. Annual per (small) system costs for those 
systems that participate in UCMR monitoring will be reduced by 
approximately $190 per year. Small systems will realize this savings 
because under the proposed program, none will be required to cover the 
cost of analysis for the unregulated chemicals (as many do under the 
existing program). Only those systems that are part of the national 
representative sample will incur any costs, and those costs will be 
labor costs only. Under full UCMR implementation, large system costs 
are increased by almost $14.0 million, primarily due to the increase in 
laboratory analytical costs. Annual per system costs for large systems 
are increased by approximately $1,000 per year under the UCM Program.
    Baseline cost to the States is estimated to be $7.5 million over 
the analogous monitoring cycle of 2001 to 2005, plus year 2000 start-up 
costs. The total savings to States under the UCMR is estimated to be 
$5.2 million. For States, this savings is attributed to a decrease in 
required labor. States will be collecting and reporting monitoring data 
from many fewer water systems since only a representative sample of 
systems serving 10,000 or fewer people will be involved in the UCMR. 
EPA costs of running the existing program are estimated at $1.9 million 
for the analogous monitoring cycle of 2001 to 2005, plus start-up 
costs. EPA costs are significantly increased under the UCMR, primarily 
because, as proposed, it will fund all small system UCMR sample 
shipping and analytical costs.
    EPA notes that reductions in costs can also be attributed to the 
``Suspension of Unregulated Contaminant Monitoring Requirements for 
Small Public Water Systems (Direct Final Rule)'' (Federal Register, 
January 8, 1999), which is being issued in conjunction with the UCMR. 
The Direct Final Rule cancels the monitoring requirements (for systems 
serving less than 10,000 people) for another round of the existing list 
of unregulated contaminants, beginning January 1, 1999. This 
cancellation is being issued because monitoring for the existing 
contaminants would overlap with monitoring for the revised program. 
Approximately two-thirds of systems serving between 3,300 and 10,000 
will save the costs of monitoring under the existing program (e.g., 
monitoring costs in 1999 and 2000) by the action of the Direct Final 
Rule, resulting an approximate system savings of $5.3 million.

C. Benefits

    The revised Unregulated Contaminant Monitoring Regulation has 
significant burden reductions, particularly for small public water 
systems. The original Unregulated Contaminant Monitoring Program, 
initiated in 1988, required that all community water systems (CWSs)

[[Page 23440]]

monitor for the 48 contaminants listed in Table 1. The States had the 
authority to waive monitoring for systems serving150 or fewer service 
connections (although these systems were required to be available for 
monitoring under the regulation). Analysis of this first round of data 
(1988-1993) indicates that well over 25,000 public water systems are 
involved in the existing unregulated contaminant monitoring program. 
This revised program will involve only 3,574 systems: 2,774 large 
systems and up to 800 small systems in the nationally representative 
sample (or possibly up to 950 small systems, depending on the selection 
of the 150 most vulnerable systems for Pre-Screen Testing and the 
extent that they would overlap with the 800 systems in the national 
representative sample). Thus, many fewer systems will be required to 
monitor than in the past.
    Additionally, for systems that will be regulated, fewer 
contaminants will be monitored; the number of contaminants are reduced 
by the UCMR rule from the current 48 to not more than 30. EPA will pay 
for the costs of the testing for the national representative sample, so 
that each small system selected will have minimal burden. EPA will not 
pay for the small system costs for collecting the samples and 
contacting the sample shipping service to pick up the samples. EPA 
anticipates that it will manage the laboratory testing program for 
these systems, minimizing time that the PWS will need to interact with 
the laboratories. Also, the laboratories contracted to perform the 
analyses will provide electronic reporting services for the small 
systems that do not have this capability. Thus, even those 800 small 
systems that are involved will have substantially reduced costs, 
compared to the past.
    In considering the full program, cost savings can also be 
attributed to the use of the small sample numbers for the Screening 
Survey and Pre-Screen Testing. The Screening Survey of only 300 systems 
(across all sizes), and the Pre-Screen Testing of up to 200 systems 
(across all sizes), will allow statistical and targeted approaches to 
be applied to emerging contaminants. These early screening approaches 
will help to determine whether contaminants are occurring in public 
water systems and whether they should be included in future Assessment 
Monitoring in the subsequent contaminant sampling cycle. These steps, 
in place of an approach applying Assessment Monitoring for all 30 
contaminants at all monitored systems, is projected to save over $50 
million per year in future Assessment Monitoring costs for large 
systems and the EPA.
    States will also see a reduction in burden. A substantial portion 
of State burden is related to the number of systems it must manage in a 
program. Even though there are some new elements to the revised UCMR, a 
burden reduction is apparent because there are significantly fewer 
systems involved, and thus a reduction in required oversight activity 
(e.g., record keeping, system notification).
    Currently, twelve data elements must be reported with each sample. 
In the proposed rule, a net increase of eight new data elements (for a 
total of 20) will be required in reporting; the additional elements are 
included to make the data more useful for analysis. The additional 
burden to systems and States is minimal, however. Most of the 
additional elements would be provided by the laboratory, and many of 
these elements are already routinely recorded by laboratories. To date, 
EPA has not required that these additional elements be sent on to the 
State or EPA. The addition of data elements will not present an 
inordinate burden on the States or systems.
    Database modifications will be minimal, since most States have 
electronic reporting. EPA plans to provide training to States on the 
review and interpretation of this data. Electronic reporting will 
facilitate minimal additional reporting burden. Once States have 
established electronic quality control of the data reported, State 
quality control review will also be minimal.
    The long-term benefits of the revised unregulated contaminant 
monitoring regulation and program are:
    1. Contaminants that do not have significant occurrence in drinking 
or source water will be identified early which will enable evaluations 
and decisions to minimize further monitoring and other resources 
otherwise committed to those contaminants;
    2. Contaminants that do have significant occurrence will trigger 
additional research on health effects and treatment, as soon as 
practical, to protect the health of persons that may be sensitive to 
them; and
    3. Use of a representative sample of small systems (which comprise 
the majority of public water systems), can provide a scientifically 
sound, statistically valid data set that can be used for improved 
analysis and program decisions at a reduced cost.

VII. Performance-Based Measurement System

    In the near future, the Agency plans to implement a performance-
based measurement system (PBMS) that would allow the option of either 
(A) using reference methods in its drinking water regulatory programs 
or (B) demonstrating and documenting ``performance criteria.'' PBMS 
would specify performance criteria or objectives that must be met for 
an analytical method to be considered comparable to a reference method 
and used broadly by other testing organizations and laboratories. As a 
result, under PBMS, the requirement to use only Agency specified and 
approved methods for SDWA regulatory programs would be removed, except 
for certain method-defined contaminants (e.g., such as Total Coliform 
and asbestos), and for data gathering prospective to regulation, such 
as the contaminants in this proposed rule.
    As noted above, many of the contaminants of interest for the 
Unregulated Contaminant Monitoring (UCM) program can be classified as 
``emerging'' and thus do not have existing reference methods, much 
less, performance criteria to describe such methods. The unregulated 
contaminant monitoring program will enable development of a reference 
method and performance criteria, as well as collect information about 
contaminant occurrence. While EPA has gathered single-matrix, multi-
laboratory data for the chemical contaminants on the UCM list, 
monitoring conducted by PWSs would provide additional multi-matrix, 
multi-laboratory data needed to develop the performance criteria 
necessary to implement PBMS for contaminants selected for standards 
setting in future regulations. The UCM testing is designed to develop 
performance criteria that would be proposed with the MCL, monitoring 
requirements, etc. for the contaminant. For these reasons, the Agency 
is proposing to specify the method to be used for UCM testing. Once a 
contaminant proceeds to standards development as an NPDWR, EPA should 
have sufficient data and method development information to be able to 
propose both a validated reference method as well as associated 
performance criteria, either of which could be used for compliance 
monitoring of the contaminant under PBMS.

VIII. Solicitation of Public Comment

    EPA solicits public comment on all aspects of this proposed 
regulation and its preamble. EPA knows that the public

[[Page 23441]]

comment period (45 days) is shorter than normal because of the 
statutory deadline. Commenters should know that for this same reason, 
no extension of the public comment period will be granted.

IX. Administrative Requirements

A. Executive Order 12866--Regulatory Planning and Review

    Under Executive Order 12866, (58 FR 51735, October 4, 1993), the 
Agency must determine whether the regulatory action is ``significant'' 
and therefore subject to OMB review and the requirements of the 
Executive Order. The Order defines ``significant regulatory action'' as 
one that is likely to result in a rule that may:
    (1) Have an annual effect on the economy of $100 million or more or 
adversely affect in a material way the economy, a sector of the 
economy, productivity, competition, jobs, the environment, public 
health or safety, or State, local, or tribal governments or 
communities;
    (2) Create a serious inconsistency or otherwise interfere with an 
action taken or planned by another agency;
    (3) Materially alter the budgetary impact of entitlements, grants, 
user fees, or loan programs or the rights and obligations of recipients 
thereof; or
    (4) Raise novel legal or policy issues arising out of legal 
mandates, the President's priorities, or the principles set forth in 
the Executive Order.'' Pursuant to the terms of Executive Order 12866, 
it has been determined that this rule is a ``significant regulatory 
action.'' As such, this action was submitted to OMB for review. Changes 
made in response to OMB suggestions or recommendations will be 
documented in the public record.

B. Executive Order 13045--Protection of Children From Environmental 
Health Risks and Safety Risks

    Executive Order 13045, ``Protection of Children from Environmental 
Health Risks and Safety Risks'' (62 FR 19885, April 23, 1997), applies 
to any rule that (1) is determined to be ``economically significant'' 
as defined under E.O. 12866, and (2) concerns an environmental health 
or safety risk that EPA has reason to believe may have a 
disproportionate effect on children. If the regulatory action meets 
both criteria, the Agency must evaluate the environmental health or 
safety effects of the planned rule on children, and explain why the 
planned regulation is preferable to other potentially effective and 
reasonably feasible alternatives considered by the Agency.
    This proposed rule is part of the Agency's overall strategy for 
deciding whether to regulate the contaminants identified on the 
Contaminant Candidate List (63 FR 10273). The purpose of today's 
proposed rule is to ensure that EPA has data on the occurrence of 
contaminants on the CCL where those data are lacking. EPA is also 
taking steps to ensure that the Agency will have data on the health 
effects of these contaminants on children through its research program. 
The Agency will use these data--both contaminant occurrence and health 
effects--to decide whether or not to regulate any of these 
contaminants.
    This proposed rule is not subject to E.O. 13045 because it is not 
economically significant as defined in E.O. 12866 and it does not 
establish environmental standards intended to mitigate health or safety 
risks. For the most part, this rule only establishes procedures for 
monitoring of unregulated contaminants on the Agency's Contaminant 
Candidate List. However, given EPA's interest in protecting children's 
health, as part of the provisions in the rule allowing State governors 
to petition EPA to add contaminants to the Unregulated Contaminant 
Monitoring List, EPA is specifically asking Governors to include any 
information that might be available regarding disproportional risks to 
the health or safety of children. Such information would help inform 
EPA's decision making regarding future lists.

C. Unfunded Mandates Reform Act

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Pub. 
L. 104-4, establishes requirements for Federal agencies to assess the 
effects of their regulatory actions on State, local, and tribal 
governments and the private sector. Under section 202 of the UMRA, EPA 
generally must prepare a written statement, including a cost-benefit 
analysis, for proposed and final rules with ``Federal mandates'' that 
may result in expenditures to State, local, and tribal governments, in 
the aggregate, or to the private sector, of $100 million or more in any 
one year. Before promulgating an EPA rule for which a written statement 
is needed, section 205 of the UMRA generally requires EPA to identify 
and consider a reasonable number of regulatory alternatives and adopt 
the least costly, most cost-effective, or least burdensome alternative 
that achieves the objectives of the rule. The provisions of section 205 
do not apply when they are inconsistent with applicable law. Moreover, 
section 205 allows EPA to adopt an alternative other than the least 
costly, most cost-effective, or least burdensome alternative if the 
Administrator publishes with the final rule an explanation of why that 
alternative was not adopted. Before EPA establishes any regulatory 
requirements that may significantly or uniquely affect small 
governments, including tribal governments, it must have developed under 
section 203 of the UMRA a small government agency plan. The plan must 
provide for notifying potentially affected small governments, enabling 
officials of affected small governments to have meaningful and timely 
input in the development of EPA regulatory proposals with significant 
Federal intergovernmental mandates, and informing, educating, and 
advising small governments on compliance with the regulatory 
requirements.
    EPA has determined that this rule does not contain a Federal 
mandate that may result in expenditures of $100 million or more for 
State, local, and tribal governments, in the aggregate, or the private 
sector in any one year. Potential annual costs of today's action for 
small entities, including local and tribal governments, are $2.1 
million for sample collection, shipping, testing and reporting for 
Assessment Monitoring, of which EPA will pay 99 percent. Average annual 
costs to States are projected to be $0.5 million for Assessment 
Monitoring oversight and reporting (over the 5-year implementation 
period). Thus, today's rule is not subject to the requirements of 
section 202 and 205 of the UMRA.
    EPA has determined that this rule contains no regulatory 
requirement that might significantly or uniquely affect small 
governments because EPA will pay for the reasonable costs of sample 
testing for the small public water systems required to sample and test 
for unregulated contaminants under this rule, including those owned and 
operated by small governments. While the covered small public water 
systems will be required to participate in the unregulated contaminant 
monitoring program, the most significant cost they would incur--the 
testing of the samples--will be paid by EPA. The only costs that small 
systems will pay would be the costs attributed to (1) the labor 
associated with reading the regulations, guidance and instructions to 
implement the monitoring requirements, (2) collecting the samples and 
packing them for shipping to the laboratory (EPA will pay for 
shipping), and (3) reporting and record keeping. Thus, today's rule is 
not subject to the requirements of section 203 of UMRA.

D. Paperwork Reduction Act

    The information collection requirements in this proposed rule have 
been submitted for approval to the

[[Page 23442]]

Office of Management and Budget (OMB) under the Paperwork Reduction 
Act, 44 U.S.C. 3501 et seq. An Information Collection Request (ICR) 
document has been prepared by EPA (ICR No. 1882.01), which presents 
estimated costs and burdens for the 1999-2001 period. In addition, a 
background cost document ``Burden and Cost Calculations for the 
Unregulated Contaminant Monitoring Regulation'' is attached as an 
appendix to the ICR, and presents the estimated costs and burdens for 
the first five-year cycle of the proposed rule. A copy of these may be 
obtained from Sandy Farmer by mail at OP Regulatory Information 
Division; U.S. Environmental Protection Agency (2137), 401 M St., SW., 
Washington, DC 20460; by email at: [email protected]; or by 
calling: (202) 260-2740. A copy may also be downloaded off the Internet 
at: http://www.epa.gov/icr.
    The information proposed to be collected under a revised UCM 
Regulation is to fulfill the statutory requirements of section 
1445(a)(2) of the Safe Drinking Water Act, as amended in 1996. The data 
to be collected will describe the source water, location and UCMR test 
results for samples taken from public water systems. The concentrations 
of any identified UCMR contaminants will be evaluated regarding health 
effects and will be considered for future regulation accordingly. 
Reporting is mandatory. The data is not subject to confidentiality 
protection.
    Burden is defined as the total time, effort, or financial resources 
expended by persons to generate, maintain, retain, or disclose or 
provide information to or for a Federal agency. This includes the time 
needed to: review instructions; develop, acquire, install and utilize 
technology and systems for the purposes of collecting, validating, 
verifying, processing, maintaining, disclosing and providing 
information; adjust the existing ways to comply with any previously 
applicable instructions and requirements; train personnel to be able to 
respond to a collection of information; search data sources; complete 
and review the collection of information; and transmit or otherwise 
disclose the information.
    The annual burden and cost estimates described below are for the 
implementation assumptions described in Section VI, which include the 
Assessment Monitoring, Screening Survey and Pre-Screen Testing 
components of the UCMR Program. For this full UCMR Program, the 
respondents to the UCMR are the 800 small water systems (in the 
national representative sample of systems serving 10,000 or fewer 
people), the 2,774 large public water systems, and the 56 States and 
primacy agents (3,630 total respondents). (As noted, it is possible 
that up to 150 additional small systems could be involved if all small 
Pre-Screen Testing systems selected fall outside of the national 
representative sample. Using an assumption of only 800 systems, 
however, is a conservative, or worst case, assumption, when estimating 
the burden and cost per system. Hence, this assumption is used in the 
following estimates.) The frequency of response varies across 
respondents and years. System costs, (particularly laboratory 
analytical costs) vary depending on the number of entry or sampling 
points. Small systems will sample and report an average of 3.4 times 
over the 5-year implementation period. Large systems will sample and 
report an average of 3.0 times over the 5-year implementation period. 
On average, States will report quarterly. Over the UCMR Program cycle 
of 2001-2005, the annual average per respondent burden hours and costs 
are: small systems--1.2 hour burden at $25 per year; large systems--2.0 
hours at $57, and $1,950 for analytical costs; and States--194 hours at 
$7,740 for labor and $500 for non-labor. In aggregate, the average 
respondent (e.g., small systems, large systems, and the States), incurs 
an annual average burden and cost of 4.8 hours per respondent, with a 
labor plus non-labor cost of $1,670 per respondent.
    Burden and cost per response for the total program are estimated to 
be: for small systems--1.7 hour burden at $36 per response; large 
systems--3.4 hours at $95 for labor, and $ 3,280 for analytical costs; 
and States--40.3 hours at $1,700 for labor. In aggregate, the average 
response (e.g., responses from small systems, large systems, and the 
States) is associated with a burden of 7.0 hours, with a labor plus 
non-labor cost of $2,460 per response.
    For Assessment Monitoring alone, the average burden and response 
are only slightly less because there is only a subset of the same 
systems involved in the Screening Survey and Pre-Screen sampling. In 
summary, for the Assessment Monitoring respondents to the UCMR are the 
800 small water systems (in the national representative sample), the 
2,774 large public water systems, and the 56 States and primacy agents 
(3,630 total respondents). The frequency of response varies across 
respondents and years. Small systems will sample and report an average 
of 3.0 times over the 5-year implementation period. Large systems will 
sample and report an average of 2.9 times over the 5-year 
implementation period. On average, States will report quarterly. Over 
the UCMR program cycle of 2001-2005, the annual average per respondent 
burden hours and costs are: Small systems--1.2 hour burden at $22 per 
year; large systems--2.0 hours at $56, and $1,680 for analytical costs; 
and States--194 hours at $7,740 for labor, and $500 for non-labor 
costs. In aggregate, the average respondent (e.g., small systems, large 
systems, and the States), incurs an annual average burden and cost of 
4.7 hours per respondent, with a labor plus non-labor cost of $1,455 
per respondent.
    Burden and cost per response for Assessment Monitoring only are 
estimated to be: For small systems--1.7 hour burden at $36 per 
response; large systems--3.4 hours at $96 for labor, and $2,840 for 
analytical costs; and States--40.3 hours at $1,700 for labor. In 
aggregate, the average response (e.g., responses from small systems, 
large systems, and the States) is associated with a burden of 7.2 
hours, with a labor plus non-labor cost of $2,210 per response.
    The Agency estimates the annual burden to EPA for total proposed 
UCMR Program activities to be approximately 16,290 hours, at an annual 
labor cost of $651,600. EPA's annual non-labor costs are estimated to 
be $2.5 million for Assessment Monitoring only, or $ 3.4 million for 
the total UCMR program (Assessment Monitoring, Screening Surveys, and 
Pre-Screen Testing).
    Non-labor costs are primarily attributed to the cost of sample 
testing for the 800 small systems. Annual burdens, as discussed, are 
based on a 5-year monitoring cycle.
    An Agency may not conduct or sponsor, and a person is not required 
to respond to a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for EPA's 
regulations are listed in 40 CFR part 9 and 48 CFR Chapter 15. Comments 
are requested on the Agency's need for this information, the accuracy 
of the provided burden estimates, and any suggested methods for 
minimizing respondent burden, including through the use of automated 
collection techniques. Send comments on the ICR document to the 
Director, OP Regulatory Information Division, U.S. Environmental 
Protection Agency (2137), 401 M St., SW., Washington, DC 20460, and to 
the Office of Information and Regulatory Affairs, Office of Management 
and Budget, 725 17th St., NW., Washington, DC 20503, marked 
``Attention: Desk Officer for EPA.'' Include the ICR number in any 
correspondence. Since OMB is required

[[Page 23443]]

to make a decision concerning the ICR between 30 and 60 days after 
April 30, 1999, a comment to OMB is best assured of having its full 
effect if OMB receives it by June 1, 1999. The final rule will respond 
to any OMB or public comments on the information collection 
requirements contained in this proposal.

E. Regulatory Flexibility Act

    Under the Regulatory Flexibility Act (RFA), as amended by the Small 
Business Regulatory Enforcement Fairness Act (SBREFA), EPA generally is 
required to prepare a regulatory flexibility analysis describing the 
impact of the rule on small entities as part of rulemaking. However, 
under section 605(b) of the RFA, if EPA certifies that the rule will 
not have a significant economic impact on a substantial number of small 
entities, EPA is not required to prepare a regulatory flexibility 
analysis. Pursuant to section 605(b) of the Regulatory Flexibility Act, 
5 U.S.C. 605(b) and for the reasons set forth below, the Administrator 
certifies that this rule will not have a significant economic impact on 
a substantial number of small entities.
    For purposes of RFA analyses for SDWA rulemakings, the Agency 
defines small entities as systems serving 10,000 or fewer customers. 
Because this is the system size category specified in SDWA as requiring 
special consideration with respect to small system flexibility, EPA 
established systems serving 10,000 or fewer persons an alternative 
small entity definition for SDWA drinking water rules for the purposes 
of regulatory flexibility analysis. This alternative definition was 
established for all drinking water rules in the Consumer Confidence 
Reports rulemaking (63 FR 44511-44536 (August 19, 1998)). EPA also 
consulted with the Small Business Administration about the alternative 
definition as it relates to small businesses. For further information 
on the establishment of this definition of small entities, see the 
referenced Federal Register notice.
    EPA has determined that the UCMR will affect small water utilities, 
since it is applicable to a subset of small community and non-transient 
noncommunity water systems. However, the systems impacted limited to a 
representative sample of approximately 800 small public water systems 
serving 10,000 or fewer persons, or 1.2 percent of systems serving 
10,000 or fewer persons. These systems will be required to conduct 
monitoring, as specified in the UCMR (i.e., collect and prepare samples 
for shipping). EPA will assume all costs for testing of the samples and 
for shipping the samples from these systems to specific certified 
laboratories located throughout the United States. EPA has set aside $2 
million from the State Revolving Fund (SRF) in Fiscal Years 1998 and 
1999, and plans to do so into the future with its authority to set 
aside SRF monies for the purposes of implementing this provision of 
SDWA.
    EPA has estimated the impact of the proposed rule and concludes 
that the rule will not have a significant economic impact on a 
substantial number of small entities. The rationale for this conclusion 
is that EPA plans to pay the full costs of shipping and testing samples 
for small systems and does not plan, under any scenario, to ask systems 
to pay these costs. (The costs to these systems will be limited to the 
labor hours associated with collecting a sample and preparing it for 
shipping.) EPA will seek to implement an optimum and scientifically 
credible UCM program that will provide a firm basis for future 
regulatory decisions.
    As noted, it is possible that up to 150 additional small systems 
could be involved in the unlikely event that all small Pre-Screen 
Testing systems selected fall outside of the national representative 
sample. Using an assumption of only 800 systems involved, however, is a 
conservative, or worst case, assumption, when estimating the burden and 
cost per system; i.e., this allocates the total cost and burden of the 
full implementation over 800 systems versus 950 systems. Hence, this 
assumption is used in the following estimates.
    EPA evaluated the cost to small entities under two scenarios. Under 
either scenario, EPA will assume the cost of shipping and testing 
samples for small systems. The ``full implementation'' scenario assumes 
full funding from funds set aside from the Drinking Water SRF through 
the year 2005. The ``limited implementation'' scenario assumes that EPA 
will fund the costs of the testing with the funds already set aside for 
this program. Under either scenario, this rule will not have a 
significant economic impact on a substantial number or small entities. 
Accordingly, EPA certifies that this rule will not have a significant 
impact on a substantial number of small entities. Cost summaries for 
both scenarios are provided below.

Full Implementation Scenario

    EPA analyzed the small entity impact for privately-owned and 
publicly-owned entities separately due to the different economic 
characteristics of these ownership types. For publicly-owned systems, 
EPA used the ``revenue test'', which compares annual system costs 
attributed to the rule to the system's annual revenues. EPA used a 
``sales test'' for privately-owned systems which involves the analogous 
comparison of UCMR-related costs to a privately-owned system's sales. 
EPA assumes that the distribution of the national representative sample 
of small systems will reflect the proportions of publicly-and 
privately-owned systems in the national inventory. The estimated 
distribution of the representative sample, categorized by ownership 
type, source water, and system size, is presented below in Table 10.

       Table 10.--Number of Publicly- and Privately-Owned Systems To Participate in Assessment Monitoring
----------------------------------------------------------------------------------------------------------------
                                      Publicly-owned systems          Privately-owned systems
                                 ----------------------------------------------------------------   Total--all
          Size category              Non-index                       Non-index                        systems
                                      systems      Index systems      systems      Index systems
----------------------------------------------------------------------------------------------------------------
                                              GROUND WATER SYSTEMS
----------------------------------------------------------------------------------------------------------------
500 and under...................              20               1              76               2              99
501 to 3,300....................             159               6              72               3             240
3,301 to 10,000.................             158               7              44               2             211
                                 -------------------------------------------------------------------------------
    Subtotal Ground.............             337              14             192               7             550
----------------------------------------------------------------------------------------------------------------
                                              SURFACE WATER SYSTEMS
----------------------------------------------------------------------------------------------------------------
500 and under...................               3               0               8               0              11

[[Page 23444]]

 
501 to 3,300....................              56               2              25               1              84
3,301 to 10,000.................             116               5              33               1             155
                                 -------------------------------------------------------------------------------
    Subtotal Surface............             175               7              66               2             250
                                 ===============================================================================
    Total.......................             512              21             258               9             800
----------------------------------------------------------------------------------------------------------------

    The basis for the UCMR RFA certification under full UCMR 
implementation is as follows: the average annual compliance costs of 
the rule represent less than one percent of revenues/sales for the 800 
small water systems that will be affected. The EPA estimates that 
Agency and system costs for implementing small system sampling for the 
full UCMR program (2001-2005) will be approximately $15.1 million. 
Since the Agency specifically structured the rule to avoid 
significantly impacting a substantial number of small entities by 
assuming all costs for laboratory analyses, shipping, and quality 
control for small entities, EPA costs comprise approximately 99 percent 
($15.0 million) of the total costs. (Note that EPA's contribution to 
the small system program is assumed to include all small system 
analytical and shipping costs, as well as all non-labor program support 
costs.) Table 11 presents the annual costs to small systems and to EPA 
for the small system sampling program, along with the number of 
participating small systems during each of the five years of the 
program.

                    Table 11.--EPA Costs for Small Systems Under Full Implementation of UCMR
----------------------------------------------------------------------------------------------------------------
                                                                        2004 (AM for
    Cost description \1\        2001 (AM)    2002 (AM &    2003 (AM &   Index only &    2005 (AM        Total
                                                SS1)          SS2)          PST)       Index only)
----------------------------------------------------------------------------------------------------------------
    Costs to EPA for Small System Program (including Assessment Monitoring, Screening Survey, and Pre-Screen
  Testing): quality assurance, ongoing coordination, data analysis, analytical costs, shipping costs, and costs
                  for contractor site visits to small Index and Pre-Screen Testing systems \2\
----------------------------------------------------------------------------------------------------------------
                                $3,392,183    $3,538,029    $3,533,202    $3,814,617      $752,537   $15,030,568
----------------------------------------------------------------------------------------------------------------
 Costs to Small Systems (including Assessment Monitoring, Screening Survey, and Pre-Screen Testing): additional
                                 labor for monitoring or monitoring assistance
----------------------------------------------------------------------------------------------------------------
                                    27,871        26,915        26,915        15,116         2,499        99,316
----------------------------------------------------------------------------------------------------------------
                                  Total Costs to EPA and Small Systems for UCMR
----------------------------------------------------------------------------------------------------------------
                                 3,420,054     3,564,944     3,560,117     3,829,733       755,036   $15,129,884
----------------------------------------------------------------------------------------------------------------
   Number of Systems to be Monitoring each Year: Non-Index and Index in 2001-2003, Index only in 2004-2005 \3\
----------------------------------------------------------------------------------------------------------------
Public......................           191           191           191           107            21           533
Private.....................            96            96            95            81             9           267
                             -----------------------------------------------------------------------------------
    Total...................           287           287           286           188            30          800
----------------------------------------------------------------------------------------------------------------
\1\ AM = Assessment Monitoring; SS1 and SS2 = Screening Surveys Years One and Two; PST = Pre-Screen Testing.
\2\ EPA costs during the year 2001 include some start-up costs that may actually be incurred during the year
  2000.
\3\ Total number of systems is 800. All 30 Index systems sample during each year 2001-2005. One-third of Non-
  Index systems sample during each year from 2001-2003. A total of 180 small systems conduct Screening Surveys
  during each year, 2002 and 2003. 158 small systems conduct the Pre-Screen Testing during 2004. The rows do not
  add across, because the same 30 Index systems sample during every year of 5-year implementation cycle, and
  because the Screening Survey systems are a subset of the original sample of 800 systems (e.g., they are
  conducting multiple types of sampling). Pre-Screen Testing systems may or may not be a subset of the original
  800 Assessment Monitoring systems.

    System costs are attributed to the additional labor required for 
reading State letters, monitoring, reporting, and record keeping. 
Assuming that systems will efficiently conduct UCMR sampling (e.g., 
coincident with other required monitoring), the estimated average 
annual per system labor burden for full UCMR implementation will be: 
$17 (0.8 hours) for ground water systems; and $31 (1.3 hours) for 
surface water systems. In total, ground water and surface water systems 
average 1.2 hour of burden per year with an average annual cost of $25. 
Average annual cost, in all cases, is less than 0.3 percent of system 
revenues/sales. Therefore, as stated above, the Administrator certifies 
that this proposed rule, as funded by EPA, will not have a significant 
economic impact on small entities. Tables 11a and 11b below present the 
estimated economic impacts in the form of revenue/sales tests for 
publicly- and privately-owned systems.

[[Page 23445]]



                             Table 12a.--UCMR Full Implementation Scenario: Analysis for Publicly-Owned Systems (2001-2005)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Annual number of systems  Average annual hours per   Average annual cost per    ``Revenue test'' \2\
                                                        impacted \1\           system (2001-2005)        system (2001-2005)    -------------------------
                   System size                   ------------------------------------------------------------------------------
                                                                Percent of                                                       Non-index      Index
                                                     Number     U.S. total   Non-index      Index      Non-index      Index      (percent)    (percent)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  GROUND WATER SYSTEMS
--------------------------------------------------------------------------------------------------------------------------------------------------------
500 and under...................................          5.8         0.01          0.8          3.0       $10.99       $42.78         0.07         0.26
501 to 3,300....................................         41.4         0.34          0.8          3.8        11.44        54.38         0.01         0.05
3,301 to 10,000.................................         42.5         1.77          1.0          4.6        29.29       128.80         0.01         0.03
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  SURFACE WATER SYSTEMS
--------------------------------------------------------------------------------------------------------------------------------------------------------
500 and under...................................          2.3         0.12          2.9          0.0        42.49         0.00         0.15         0.00
501 to 3,300....................................         17.9         0.98          1.6          5.2        22.66        75.40         0.01         0.04
3,301 to 10,000.................................         30.5         3.03          1.3          5.0        35.28       140.00         0.00         0.02
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Calculated as \1/5\ of the Non-Index sample, plus all Index systems for each year from 2001-2005; actual sampling for Non-Index systems takes place
  over three years, while that of Index systems occurs over each of five years. Since Screening Survey systems are a subset of the Assessment Monitoring
  systems, this does not affect the average annual number of systems (e.g., these systems are conducting monitoring for two components of the UCM
  Program at the same time).
\2\ The ``Revenue Test'' was used to evaluate the economic impact of an information collection on small government entities (e.g., publicly-owned
  systems); costs are presented as a percentage of median annual revenue in each size category.


                             Table 12b.--UCMR Full Implementation Scenario: Analysis for Privately-Owned Systems (2001-2005)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Annual number of systems  Average annual hours per   Average annual cost per       Sales test \2\
                                                        impacted \1\           system (2001-2005)      system (2001-2005) \1\  -------------------------
                   System size                   ------------------------------------------------------------------------------
                                                                Percent of                                                       Non-index      Index
                                                     Number     U.S. total   Non-index      Index      Non-Index      Index      (percent)    (percent)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  GROUND WATER SYSTEMS
--------------------------------------------------------------------------------------------------------------------------------------------------------
500 and under...................................         21.4         0.05          0.8          3.0        10.99        42.78         0.07         0.27
501 to 3,300....................................         18.8         0.15          0.8          3.8        11.44        54.38         0.01         0.05
3,301 to 10,000.................................         11.9         0.50          1.0          4.6        29.29       128.80         0.00         0.02
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  SURFACE WATER SYSTEMS
--------------------------------------------------------------------------------------------------------------------------------------------------------
500 and under...................................          6.5         0.34          2.9          0.0        42.49         0.00         0.19         0.00
501 to 3,300....................................          8.1         0.45          1.6          5.2        22.66        75.40         0.01         0.05
3,301 to 10,000.................................          8.5         0.85          1.3          5.0        35.28       140.00         0.01         0.02
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Calculated as \1/5\ of the Non-Index sample, plus all Index systems for each year from 2001-2005; actual sampling for Non-Index systems takes place
  over three years, while that of Index systems occurs over each of five years. Since Screening Survey systems are a subset of the Assessment Monitoring
  systems, this does not affect the average annual number of systems (e.g., these systems are conducting monitoring for two components of the UCM
  Program at the same time).
\2\ The ``Sales Test'' was used to evaluate the economic impact of an information collection on small private entities (e.g., privately-owned systems);
  costs are presented as a percentage of median annual sales in each size category.

Limited Implementation Scenario

    Despite the expected $2 million per year budget, EPA recognizes 
that funding levels vary from year to year and thus cannot guarantee 
the precise amount that will ultimately be available to implement its 
UCM program (although a considerable portion of those funds are 
currently on hand). In the event that an amount commensurate with 
funding the optimal UCM program (in terms of numbers of small systems 
sampled and numbers of contaminants analyzed) may not be available, the 
Agency will adjust the UCM program to accommodate the available funds. 
This adjustment may necessitate use of relatively fewer sample sites, 
testing of fewer contaminants, or both. EPA would use a random number 
generator select a representative sample of systems that would 
accommodate the available funds.
    While the Agency considers the scenario of no additional funding to 
be unlikely, EPA also evaluated the scenario of ``current funds only'' 
for purposes of this RFA analysis. This ``current available funds'' 
scenario is the case in which EPA would receive no further funding for 
small system testing beyond the $4 million that is currently set aside 
from the State Revolving Funds from Federal Fiscal Years 1998 and 1999. 
EPA anticipates funding this program such that no small system would 
incur testing costs as intended in the legislation. Small systems would 
only be responsible for taking the sample. By analyzing small system 
impact under such a scenario, EPA can demonstrate that, regardless of 
funding levels, this rule will not have a significant economic impact 
on a substantial number of small entities. Given the flexibility of the 
proposed rule, EPA can ensure defensible results, balanced with 
available funding.
    In the optimal anticipated program, the sample of 800 systems is 
derived by applying a 99 percent confidence level, with 1 percent error 
tolerance. To accommodate a $4 million budget, the representative 
sample of small systems would be reduced to approximately 390 systems. 
Although this smaller sample size would be less rigorous than the 
anticipated sample of 800 systems, the sample error would still remain 
within a range of plus or minus 5 percent. These 390 systems would 
incur only labor costs for collecting and packing

[[Page 23446]]

the samples, while EPA would pay the shipping and testing costs for 
these samples.
    With the currently available $4 million, EPA will be able to fund 
approximately 48 percent of the planned Assessment Monitoring program 
for small systems. To estimate the costs under this scenario, it is 
assumed that only the Assessment Monitoring component of UCMR would be 
implemented. It is also assumed that the smaller representative sample 
would be allocated across system size categories in the same 
proportions as those in the sample of 800 systems, with ten of these 
systems being Index sites, as seen below in Table 13. Furthermore, 
preparations for the Screening Surveys, Pre-Screen Testing, and future 
UCMR cycles are assumed to be dropped, since with limited funds, 
current implementation would take precedence over planning for further 
monitoring. Finally, for the cost analysis of this current funds 
scenario, it is assumed that the national representative sample will 
reflect the proportions of publicly-and privately-owned systems in the 
national inventory of public water systems.1 Because EPA's 
statistical approach utilizes a random selection process for systems in 
the national representative sample, publicly--and privately-owned 
systems should be selected in the same proportions for that sample as 
they occur in set of all community and non-transient, noncommunity 
water systems in the nation.
---------------------------------------------------------------------------

    \1\ Publicly- and privately-owned systems allocations are 
estimated using data from the 1995 Community Water System Survey. 
Publicly owned systems are those that are owned by a city, town, 
township, village, municipal government, State or federal 
government, or any other publicly-owned or operated system. 
Privately-owned systems include those owned by private investors or 
homeowners' associations.
---------------------------------------------------------------------------

    The Agency is concerned that a reduced sample size will reduce the 
statistical likelihood that the observed contaminant occurrence levels 
will be representative of actual occurrence across the nation. Because 
of this, the Agency will actively pursue funding for the full program 
described in this Preamble.

 Table 13.--Number of Publicly- and Privately-Owned Systems To Participate in Assessment Monitoring, for Limited
                                                Funding Program 1
----------------------------------------------------------------------------------------------------------------
                                      Publicly- owned systems         Privately-owned systems
                                 ----------------------------------------------------------------   Total--all
          Size category              Non-index                       Non-index                        systems
                                      systems      Index systems      systems      Index systems
----------------------------------------------------------------------------------------------------------------
                                              GROUND WATER SYSTEMS
----------------------------------------------------------------------------------------------------------------
500 and under...................              11               0              38               1              50
501 to 3,300....................              80               2              36               1             119
3,301 to 10,000.................              79               2              22               1             104
                                 -------------------------------------------------------------------------------
    Subtotal Ground.............             170               4              96               3             273
----------------------------------------------------------------------------------------------------------------
                                              SURFACE WATER SYSTEMS
----------------------------------------------------------------------------------------------------------------
500 and under...................               1               0               4               0               5
501 to 3,300....................              28               1              13               0              42
3,301 to 10,000.................              58               2              16               0              76
                                 -------------------------------------------------------------------------------
    Subtotal Surface............              87               3              33               0             123
                                 ===============================================================================
    Total.......................             257               7             129               3            396
----------------------------------------------------------------------------------------------------------------
\1\ The Limited Funding Program assumes that the only funds available to run the program are those that are
  currently in hand--$4 million of set aside funds from Federal Fiscal Years 1998 and 1999. This is a ``worst
  case'' funding scenario.

    Under the limited funding scenario, EPA costs for Assessment 
Monitoring would primarily be incurred from 2001 to 2003. Systems are 
assumed to sample during one year of the three-year period, with one-
third of systems sampling during each year. However, Index systems are 
assumed to monitor during each of the three Assessment Monitoring 
years. The distribution of costs to EPA and small systems over the 
entire five years is presented below in Table 14.

                       Table 14.--EPA Costs for Small Systems--Limited $4 million Program
----------------------------------------------------------------------------------------------------------------
      Cost description            2001          2002          2003          2004          2005          Total
----------------------------------------------------------------------------------------------------------------
     Costs to EPA for Assessment Monitoring Program: Quality assurance, ongoing coordination, data analysis,
----------------------------------------------------------------------------------------------------------------
                                $1,367,947    $1,082,341    $1,082,341      $280,422      $186,948    $3,999,999
----------------------------------------------------------------------------------------------------------------
     Costs to Small Systems (Assessment Monitoring): Including additional labor for monitoring or monitoring
----------------------------------------------------------------------------------------------------------------
                                    13,405        11,756        11,756             0             0        36,917
----------------------------------------------------------------------------------------------------------------
                         Total Costs to EPA and Small Systems for Assessment Monitoring
----------------------------------------------------------------------------------------------------------------
                                 1,381,352     1,094,097     1,094,097       280,422       186,948     4,036,916
----------------------------------------------------------------------------------------------------------------

[[Page 23447]]

 
              Number of Systems each Year: Assessment Monitoring and Index Systems in 2001-2003 \1\
----------------------------------------------------------------------------------------------------------------
Public......................            92            92            92             0             0           264
Private.....................            46            46            46             0             0           132
                             -----------------------------------------------------------------------------------
    Total...................           138           138           138             0             0           396
----------------------------------------------------------------------------------------------------------------
\1\ Rows do not add across because the 10 Index systems sample during each year 2001-2003. One-third of Non-
  Index systems sample during each year from 2001-2003.

    Under this limited $4 million program, EPA costs represent 
approximately 98 percent of the national cost for the small system 
sampling program. As in full UCMR implementation, small system costs 
are attributed to the additional labor required for reading State 
letter, monitoring, reporting, and record keeping. It is estimated that 
under the limited program (e.g., Assessment Monitoring only), the 
average annual per system labor burden will be: $15 (0.7 hours) for 
ground water systems; and $27 (1.26 hours) for surface water systems. 
In total, ground water and surface water systems average 0.9 hours of 
burden per year, with an average annual cost of $19. System burdens 
here are lower than in the full implementation scenario primarily 
because no Screening Surveys or Pre-Screen Testing will occur under 
this scenario.
    Through revenue and sales tests, determinations of economic impact 
are presented below in Tables 14a and 14b, respectively. Under this 
limited $4 million program, systems will be subject to less required 
monitoring than in the full UCMR program. For both full UCMR 
implementation and the limited funding scenario, average annual cost is 
in all cases lower than 1 percent of annual sales/revenues. Thus, even 
in this worst case, limited implementation scenario, EPA certifies that 
this proposed rule would not impose a significant economic impact on 
small entities.

                            Table 15a.--UCMR Limited Implementation Scenario: Analysis for Publicly-Owned Systems (2001-2005)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Annual number of systems  Average annual hours per   Average annual cost per    ``Revenue Test'' \2\
                                                        impacted \1\           system (2001-2005)        system (2001-2005)             (percent)
                   System size                   --------------------------         (percent)        ---------------------------------------------------
                                                                Percent of --------------------------
                                                     Number     U.S. total   Non-Index      Index      Non-Index      Index      Non-Index      Index
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  GROUND WATER SYSTEMS
--------------------------------------------------------------------------------------------------------------------------------------------------------
500 and under...................................          2.2         0.00          0.3          0.6        $4.48        $8.65         0.03         0.05
501 to 3,300....................................         17.1         0.14          0.3          0.7         5.05         9.81         0.00         0.01
3,301 to 10,000.................................         17.2         0.72          0.1          0.8         2.81        23.71         0.00         0.00
                                                 -------------------------------------------------------------------------------------------------------
                                                                  SURFACE WATER SYSTEMS
--------------------------------------------------------------------------------------------------------------------------------------------------------
500 and under...................................          0.3         0.01          0.5          0.0        $7.97        $0.00         0.03         0.00
501 to 3,300....................................          6.0         0.33          0.7          1.1        10.45        16.63         0.01         0.01
3,301 to 10,000.................................         12.6         1.25          0.0          1.1         0.00        30.99         0.00         0.00
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Calculated as \1/5\ of publicly-owned Non-Index sample, plus all public Index systems for each year from 2001-2003; actual sampling for Non-Index
  takes place over three years, Index over each of three years.
\2\ The ``Revenue Test'' was used to evaluate the economic impact of an information collection on small governments (e.g., publicly-owned systems);
  costs are presented as a percentage of median annual revenue in each size category.


                           Table 15b.--UCMR Limited Implementation Scenario: Analysis for Privately Owned Systems (2001-2005)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Annual number of systems  Average annual hours per   Average annual cost per     ``Sales Test'' \2\
                                                        impacted \1\           system (2001-2005)      system (2001-2005) \1\           (percent)
                   System size                   --------------------------         (percent)        ---------------------------------------------------
                                                                Percent of --------------------------
                                                     Number     U.S. total   Non-Index      Index      Non-Index      Index      Non-Index      Index
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  GROUND WATER SYSTEMS
--------------------------------------------------------------------------------------------------------------------------------------------------------
500 and under...................................          8.0         0.02          0.6          1.9        $8.06       $27.41         0.05         0.17
501 to 3,300....................................          7.8         0.06          0.6          2.1         9.15        30.89         0.01         0.03
3,301 to 10,000.................................          4.8         0.20          0.8          2.6        22.16        73.92         0.00         0.01
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  SURFACE WATER SYSTEMS
--------------------------------------------------------------------------------------------------------------------------------------------------------
500 and under...................................          0.8         0.04          1.1          0.0       $15.41        $0.00         0.07         0.00
501 to 3,300....................................          2.7         0.15          1.2          3.2        17.07        46.98         0.01         0.03

[[Page 23448]]

 
3,301 to 10,000.................................          3.5         0.35          1.1          3.1        31.35        87.36         0.01         0.02
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Calculated as \1/5\ of the Non-Index sample, plus all Index systems for each year from 2001-2005; actual sampling for Non-Index systems takes place
  over three years, while that of Index systems occurs over each of three years.
\2\ The ``Sales Test'' was used to evaluate the economic impact of an information collection on small private entities (e.g., privately-owned systems);
  costs are presented as a percentage of median annual sales in each size category.

F. National Technology Transfer and Advancement Act

    Under Sec. 12(d) of the National Technology Transfer and 
Advancement Act (NTTAA), the Agency is required to use voluntary 
consensus standards in its regulatory activities unless doing so would 
be inconsistent with applicable law or otherwise impractical. Voluntary 
consensus standards are technical standards (e.g., material 
specifications, analytical methods, sampling procedures, business 
practices, etc.) that are developed or adopted by voluntary consensus 
standard bodies. Where available and potentially applicable voluntary 
consensus standards are not used by EPA, the Act requires the Agency to 
provide Congress, through the Office of Management and Budget (OMB), an 
explanation of the reasons for not using such standards.
    In preparing this proposal, EPA searched for consensus methods and 
the methods found were published by the three major voluntary consensus 
method organizations, Standard Methods, AOAC International, and 
American Society for Testing and Materials (ASTM), that would be 
acceptable for compliance determinations under SDWA for the UCM List. 
The voluntary consensus methods found are listed in preamble section 
III.A.1.(c), Analytical Methods Applicable to the Monitoring List. For 
the Assessment Monitoring portion of the proposed rule, EPA is 
approving the use of all of the non-EPA analytical methods, adopted by 
these voluntary consensus groups, that are applicable to the analyses 
of these unregulated contaminants, when used in conjunction with the 
required quality-control practices specified in the rule.
    For those chemical and microbiological parameters not included in 
the Assessment Monitoring portion of this proposal, EPA was unable to 
find either an EPA or voluntary consensus method organization method 
that was applicable to the monitoring required. In those cases where 
the contaminant was listed in a consensus method organizations method, 
the method either used technology that EPA believes is not consistent 
with modern laboratory practices (large volume liquid-liquid acid base 
neutral extractions, and packed column chromatography), or the 
contaminant was subject to rapid degradation in samples stored under 
the specified conditions. Therefore, EPA is conducting the methods 
development necessary to establish acceptable methods for the 
determination of these parameters.
    EPA welcomes comments on this aspect of the proposed rulemaking 
and, specifically invites the public to identify potentially applicable 
voluntary consensus standards and to explain why such standards should 
be used in this regulation.

G. Executive Order 12898--Federal Actions to Address Environmental 
Justice in Minority Populations and Low-Income Populations

    Executive Order 12898, ``Federal Actions to Address Environmental 
Justice in Minority Populations and Low-Income Populations'' (February 
11, 1994), focuses federal attention on the environmental and human 
health conditions of minority populations and low-income populations 
with the goal of achieving environmental protection for all 
communities.
    By seeking to identify unregulated contaminants that may pose 
health risks via drinking water from all Public Water Systems, the 
unregulated contaminant monitoring regulation furthers the protection 
of public health for all citizens, including minority and low-income 
populations using public water supplies. Using a statistically-derived 
set of systems for the national representative sample that is 
population-weighted within each system size category in each State, the 
proposed rule ensures that no group within the population is under 
represented.

H. Executive Order 12875--Enhancing Intergovernmental Partnerships

    Under Executive Order 12875, EPA may not issue a regulation that is 
not required by statute and that creates a mandate upon a State, local 
or tribal government, unless the Federal government provides the funds 
necessary to pay the direct compliance costs incurred by those 
governments or EPA consults with those governments. If EPA complies by 
consulting, Executive Order 12875 requires EPA to provide to the Office 
of Management and Budget a description of the extent of EPA's prior 
consultation with representatives of affected State, local and tribal 
governments, the nature of their concerns, any written communications 
from the governments, and a statement supporting the need to issue the 
regulation. In addition, Executive Order 12875 requires EPA to develop 
an effective process permitting elected officials and other 
representatives of State, local and tribal governments ``to provide 
meaningful and timely input in the development of regulatory proposals 
containing significant unfunded mandates.''
    EPA has concluded that this rule will create a mandate on State, 
local, and tribal governments and that the Federal government will not 
provide the funds necessary to pay the full direct costs incurred by 
these governments in complying with the mandate. However, EPA will pay 
for the sample testing costs of small systems serving 10,000 or fewer 
persons and has set aside funds in its budget to do so.
    EPA consulted with State, local, and tribal governments to enable 
them to provide meaningful and timely input in the development of this 
rule. Specifically, EPA received input through its public stakeholder 
process from 21 States and eight large water systems serving more than 
10,000 persons, as well as 62 other Federal, State and local government 
agencies, non-profit organizations, and associations and industry who 
attended

[[Page 23449]]

17 public meetings beginning in December 1996 and continuing through 
June 1998, in Washington, DC. EPA announced five of these meetings in 
the Federal Register to allow as broad as possible a representation at 
these meetings, with the remaining meetings being topical meetings of 
representatives from the public meetings. EPA also sent out nearly 400 
targeted mailings directly to 360 tribes, tribal organizations, and 
small water system organizations to ensure that they were informed of 
the proposed rule's expected requirements and had an opportunity to 
comment on these requirements. The principal concerns raised were that: 
(1) EPA should fund the testing of samples from systems serving 10,000 
or fewer persons, and that larger systems should provide their own 
testing. (2) EPA should implement a monitoring program commensurate 
with the information needed about and the analytical methods that could 
reliably be used for the contaminants of concern. (3) EPA should 
establish as full a list of 30 contaminants as possible to maximize the 
use of the program. EPA believes this proposal fully addresses these 
concerns. (4) EPA should consider targeted, rather than representative 
random, sampling for tribal water systems. EPA is asking for public 
comment on the issue of targeted monitoring. (5) EPA should consider 
the applicability of ``treatment as a State'' for Tribes for the 
purposes of this regulation. EPA is asking for public comment on this 
issue.

I. Executive Order 13084--Consultation and Coordination with Indian 
Tribal Governments

    Under Executive Order 13084, EPA may not issue a regulation that is 
not required by statute, that significantly or uniquely affects the 
communities of Indian tribal governments, and that imposes substantial 
direct compliance costs on those communities, unless the Federal 
government provides the funds necessary to pay the direct compliance 
costs incurred by the tribal governments or EPA consults with those 
governments. If EPA complies by consulting, Executive Order 13084 
requires EPA to provide to the Office of Management and Budget, in a 
separately identified section of the preamble to the rule, a 
description of the extent of EPA's prior consultation with 
representatives of affected tribal governments, a summary of the nature 
of their concerns, and a statement supporting the need to issue the 
regulation. In addition, Executive Order 13084 requires EPA to develop 
an effective process permitting elected officials and other 
representatives of Indian tribal governments ``to provide meaningful 
and timely input in the development of regulatory policies on matters 
that significantly or uniquely affect their communities.''
    Today's rule does not significantly or uniquely affect the 
communities of Indian tribal governments. Only one tribal water system 
serves more than 10,000 persons. All the other tribal water systems 
serve 10,000 or fewer persons and in today's proposal would have an 
equal probability of being selected in the national representative 
sample of systems of this size for which EPA will pay the costs of 
testing of unregulated contaminants. Thus, these tribal water systems 
would be treated the same as water systems of a State.
    This rule will not impose substantial direct compliance costs on 
such communities either because the Federal government will provide 
most of the funds necessary to pay the direct costs incurred by the 
tribal governments in complying with the rule, with the exception of 
the one large tribal water system. Accordingly, the requirements of 
section 3(b) of Executive Order 13084 do not apply to this rule. 
Nevertheless, in developing this rule, EPA consulted with 
representatives of tribal governments pursuant to both Executive Order 
12875 and Executive Order 13084. The extent of EPA's consultation, the 
nature of the governments' concerns, and EPA's position supporting the 
need for this rule, are discussed in the preamble section that 
addresses compliance with Executive Order 12875. Tribes were consulted 
and raised issues concerning the utility of a targeted, rather than a 
representative random, sampling approach, and the applicability of 
``treatment as a State'' under this proposed rule. The Agency is 
requesting public comment on these issues. Systems serving 10,000 or 
fewer persons on tribal lands will have the same opportunity to be 
selected for participation in the monitoring program as any other 
system of that size and EPA will pay for the testing costs.

X. Public Involvement in Regulation Development

    EPA's Office of Ground Water and Drinking Water has developed a 
process for stakeholder involvement in its regulatory activities for 
the purpose of providing early input to regulation development. 
Activities related to the Unregulated Contaminant Monitoring Regulation 
included meetings for developing the Contaminant Candidate List (CCL) 
and the information requirements of the National Drinking Water 
Contaminant Occurrence Data Base (NCOD), as well as specific meetings 
focused on revising the unregulated contaminant monitoring program. 
During the development of the UCMR, stakeholders from a wide range of 
public and private entities provided key perspectives. Representatives 
from public water systems, States, industry, and other organizations 
attended two stakeholders meetings to discuss options directly related 
to the UCMR. An additional 17 meetings were held with stakeholders and 
the public concerning issues related to the UCMR. In total, twenty-one 
State health and environmental agencies, five water systems, six water 
associations, six health associations, five industrial associations, 
four environmental organizations, four community and consumer 
organizations, twenty-nine companies, and seven federal agency offices 
participated in meetings that were instrumental in the development of 
the proposed regulation.
    As noted above, the CCL identifies contaminants for which EPA may 
take regulatory action and for which EPA needs additional data. The 
contaminants for which additional data are needed before EPA can 
determine their regulatory status include contaminants on the 
Unregulated Contaminant Monitoring List. The meetings to develop the 
CCL have included stakeholder meetings to discuss the list broadly and 
meetings focused on particular issues conducted through the National 
Drinking Water Advisory Council's (NDWAC) Working Group on Occurrence 
and Contaminant Selection, as follows:

December 2-3, 1996 Stakeholders Meeting
April 3-4, 1997 NDWAC Working Group
June 23, 1997 NDWAC Working Group
July 17, 1997 NDWAC Working Group
January 7, 1998 NDWAC Conference Call

    These meetings resulted in the Drinking Water Contaminant Candidate 
List (63 FR 10274, March 2, 1998) The contaminants that are proposed in 
this rule for unregulated contaminant monitoring are taken from the CCL 
``Occurrence Priorities.''
    The NCOD development activities have included ten public meetings 
on information requirements that should be considered for inclusion in 
that data base. These meetings were held from October 1997 to February 
1998. The work of the NCOD development team has been incorporated in 
the preparation of this proposed unregulated contaminant monitoring 
regulation as the reporting requirements

[[Page 23450]]

for sample testing. Several documents are included in the docket for 
this rule concerning the NCOD development which were used in the public 
meetings:

Options for the National Drinking Water Contaminant Occurrence Data 
Base, Background Document (Working Draft), EPA 815-D-97-001, May 1997;
National Drinking Water Contaminant Occurrence Data Base--Development 
Strategy, Background Document (Working Draft), EPA 815-D-97-005, 
December 1997; and
Options for Design of the National Drinking Water Contaminant 
Occurrence Data Base, Background Document (Working Draft), EPA 815-D-
98-001, January 1998.

    EPA held its first stakeholders meeting to discuss options for the 
development of the Unregulated Contaminant Monitoring Regulation on 
December 2-3, 1997, in Washington, DC. A range of stakeholders attended 
that meeting, including representatives of public water systems, 
States, industry, health and laboratory organizations, and the public. 
EPA prepared a background document for the meeting, Options for 
Developing the Unregulated Contaminant Monitoring Regulation (Working 
Draft), EPA 815-D-97-003, November 1997. A summary of the meeting is 
also available. Prior to preparation of this proposed regulation, EPA 
held a second stakeholders meeting on June 3-4, 1998, to obtain input 
from interested parties on significant issues evolving from drafting 
the regulation, which needed further public input. EPA prepared a 
public review document for that meeting, Background Information and 
Draft Annotated Outline for a Proposed Unregulated Contaminant 
Monitoring Regulation, Background Document, (Working Draft), May 1998. 
A meeting summary is available. EPA also sent special requests for 
review of stakeholder documents to more than 360 tribes (exclusive of 
the Alaskan native villages) and to small systems organizations to 
obtain their input.
    In all, EPA has held 17 public meetings with stakeholders and 
interested parties related directly or closely to the proposed 
Unregulated Contaminant Monitoring Regulation.

XI. References

Barbash, J.E., and E.A. Resek. 1996. Pesticides in Ground Water, 
volume two of the series Pesticides in the Hydrologic System. Ann 
Arbor Press, Inc., Chelsea, Michigan.
Battaglin, W., and Hay, L. 1996. Effects of sampling strategies on 
estimates of annual mean herbicide concentrations in Midwestern 
rivers. Environmental Science and Technology, v. 30, p. 889-896.
Cowart, J.B., W.C. Burnett, P.A. Chin, K. Harada. 1987. Occurrence 
of Po-210 in Natural Waters in Florida, in Trace Substances in 
Environmental Health-XXI. D.D. Hemphill, Ed., University of 
Missouri, Columbia.
Hallberg, G. 1989a. Pesticide pollution of groundwater in the humid 
United States; In Bouwer, H., and Bowman, R.S., eds., Effect of 
Agriculture on Groundwater. Agriculture, Ecosystems, and 
Environment, v. 26, p. 299-367.
Hallberg, G.R. 1989b. Nitrate in groundwater in the United States, 
In Follett, R.F., ed., Nitrogen Management and Groundwater 
Protection; Chapter 3, p. 35-74. Elsevier Sci. Pub., Amsterdam, The 
Netherlands.
Hallberg, G., and D. Keeney. 1993. Nitrate. In Alley, W.A., Regional 
Ground-Water Quality; Chapter 2, p. 297-322. Van Nostrand Reinhold, 
New York, NY.
Harada, Koh, W.C. Burnett, P.A. LaRock, and J.B. Cowart. 1989. 
Polonium in Florida groundwater and its possible relationship to the 
sulfur cycle and bacteria. Geochemica et Cosmochimica Acta, v. 53, 
pp. 143-150.
Larson, S.J., P.D. Capel, and M.S. Majewski. 1997. Pesticides in 
Surface Waters, volume three of the series Pesticides in the 
Hydrologic System. Ann Arbor Press, Inc., Chelsea, Michigan.
Pinsky, P., M. Lorber, K. Johnson, B. Kross, L. Burmeister, A. 
Wilkins, and G. Hallberg. 1997. A study of the temporal variability 
of atrazine in private well water. Environmental Monitoring and 
Assessment, v. 47, p. 197-221.
Upchurch, S.B. 1991. Radiochemistry of Uranium-Series Isotopes in 
Groundwater. Florida Institute of Phosphate Research (05-022-092)

List of Subjects

40 CFR Part 141

    Analytical methods, Chemicals, Environmental protection, 
Intergovernmental relations, Microorganisms, Monitoring, Water supply.

40 CFR Part 142

    Analytical methods, Chemicals, Environmental protection, 
Intergovernmental relations, Microorganisms, Monitoring, Water supply.

    Dated: April 14, 1999.
Carol M. Browner,
Administrator.

    For the reasons set out in the preamble, title 40 of the Code of 
Federal Regulations is proposed to be amended as follows:

PART 141--NATIONAL PRIMARY DRINKING WATER REGULATIONS

    1. The authority citation for part 141 continues to read as 
follows:

    Authority: 42 U.S.C. 300f, 300g-1, 300g-2, 300g-3, 300g-4, 300g-
5, 300g-6, 300j-4, 300j-9, and 300j-11.

    2. Section 141.35 is revised to read as follows:


Sec. 141.35  Reporting of unregulated contaminant monitoring results.

    (a) Does this reporting apply to me? This section applies to any 
owner or operator of a public water system required to monitor for 
unregulated contaminants under Sec. 141.40. This rule requires you to 
report the results of this monitoring.
    (b) To whom must I report? (1) You must report the results of 
unregulated contaminant monitoring to the primary enforcement authority 
for the public water system program for your state, which will usually 
be the State drinking water agency, but will, in some parts of the 
country, be the EPA Regional office. (The primary enforcement authority 
for a public water system is also known as the ``primacy agency'.) You 
must also notify the public of the monitoring results as provided in 
Subpart O (Consumer Confidence Reports) and Subpart Q (Public 
Notification) of this part.
    (2) Exception. You do not need to report results of the screening 
survey, if you are a system serving a population of 10,000 or less, or 
the results of a pre-screen test, since in both cases EPA will arrange 
for testing and reporting of the results. However, you will still need 
to comply with public notification requirements for these results.
    (c) When do I report monitoring results? You must report the 
results of unregulated contaminant monitoring within ten (10) days of 
receiving the results from the laboratory or within the first ten (10) 
days following the end of the required monitoring period specified by 
the primacy agency, whichever comes first.
    (d) What information must I report? You must report the information 
specified in the following table:

[[Page 23451]]



   Table 1.--Unregulated Contaminant Monitoring Reporting Requirements
------------------------------------------------------------------------
         Data element                          Definition
------------------------------------------------------------------------
1. Public Water System (PWS)   The code used to identify each PWS. The
 Identification Number.         code begins with the standard two-
                                character postal State abbreviation; the
                                remaining seven characters are unique to
                                each PWS.
2. Sampling Station Type.....  The sampling station type from which the
                                sample came. The valid choices are:
                               (a) Finished Water from treatment system.
                               (b) Finished/treated water from Entry
                                Point to the distribution system after
                                treatment.
                               (c) Finished/treated water from Within
                                the Distribution System.
                               (d) Finished/treated water from End of
                                the Distribution line with longest
                                residence time.
                               (e) Finished/treated water from household/
                                drinking water tap.
                               (f) Finished/treated water from unknown
                                location.
                               (g) Other Finished/treated water.
                               (h) Raw/untreated water.
3. Water Source Type.........  The source type represented by the
                                sample. The valid choices are:
                               (a) Surface water from a stream or
                                purchased surface water from a stream.
                               (b) Surface water from a lake or
                                reservoir, or purchased surface water
                                from a lake or reservoir.
                               (c) Ground water under the direct
                                influence of surface water or purchased
                                Ground water under the direct influence
                                of surface water.
                               (d) Ground water or purchased ground
                                water.
4. Sample Identification       A unique identifier assigned by the PWS
 Number.                        for each sample.
5. Sample Collection Date....  The date the sample is collected.
6. Contaminant...............  The unregulated contaminant for which the
                                sample is being analyzed.
7. Analytical Results--Sign..  An alphanumeric value indicating whether
                                the sample analysis result was:
                               (a) (<) ``less than'' means the
                                contaminant was not detected or was
                                detected at a level ``less than'' the
                                MRL.
                               (b) (=) ``equal to'' means the
                                contaminant was detected at a level
                                ``equal to'' the value reported in
                                ``Analytical Result--Value.''
8. Analytical Result--Value..  The actual numeric value of the analysis
                                for chemical and microbiological
                                results.
9. Analytical Result--Unit of  The unit of measurement for the
 Measure.                       analytical results reported. (e.g.,
                                micrograms per liter, g/L;
                                colony-forming units per milliliter, CFU/
                                mL, etc.)
10. Analytical Method Number.  The method number of the analytical
                                method used.
11. Public Water System        An identification number established by
 Facility Identification        the State, or, at the State's
 Number--Source Intake/Well,    discretion, the PWS, and unique to the
 Treatment Plant and Sampling   system for an intake for each source of
 Station.                       water, a treatment plant and a sampling
                                station. Within each PWS, each intake,
                                treatment plant and sampling point must
                                receive a unique identification number,
                                including, for intake, surface water
                                intake, ground water well or wellfield
                                centroid, and including, for sampling
                                station, entry points to the
                                distribution system, wellhead, intake,
                                or locations within the distribution
                                system. The same identification number
                                must be used consistently through the
                                history of unregulated contaminant
                                monitoring to represent the facility.
12. Public Water System        The facility type represented by the
 Facility Type.                 water system facility identification
                                number:
                               (a) Intake (for surface water sources).
                               (b) Well or wellfield (for ground water
                                sources).
                               (c) Treatment Plant.
                               (d) Sampling Station.
                               (e) Entry Point to Distribution System.
                               (f) Reservoir.
                               (g) Booster Station.
                               (h) Unknown.
13. Latitude of the Public     The east-west coordinate of each source
 Water System Facility for      intake, well or wellfield centroid, and
 Source Intake/Well and         treatment plant associated with a sample
 Treatment Plant.               expressed as decimal degrees.
14. Longitude of the Public    The north-south coordinate of each source
 Water System Facility for      intake, well or wellfield centroid, and
 Source Intake/Well and         treatment plant associated with a sample
 Treatment Plant.               expressed as decimal degrees.
15. Sample Type..............  The type of sample collected. Permitted
                                values include:
                               (a) Reference Sample--calibration or QC
                                samples.
                               (b) Field Sample--sample collected and
                                submitted for analysis under this rule.
                               (c) Confirmation Sample--a sample
                                analyzed to confirm an initial
                                contaminant detection.
                               (d) Field Blank--reagent water or other
                                blank matrix placed in a sample
                                container in the laboratory and treated
                                as a sample in all respects, including
                                shipment to the sampling site, storage,
                                preservation, and all analytical
                                procedures.
                               (e) Equipment Blank--samples generated by
                                processing reagent water through the
                                equipment using the same procedures used
                                in the field to demonstrate that the
                                equipment is free from contamination.
                               (f) Split Sample--sample divided into sub-
                                samples submitted to different
                                laboratories or analysts for analysis.
                               (g) Duplicate Sample--two aliquots of the
                                same sample analyzed separately with
                                identical procedures.
                               (h) Spiked Sample--a sample to which
                                known quantities of the method analytes
                                are added.
16. Detection Level..........  ``Detection level'' is referring to the
                                detection limit applied to both the
                                method and equipment. Detection limits
                                are the lowest concentration of a target
                                contaminant that a given method or piece
                                of equipment can reliably ascertain and
                                report as greater than zero (i.e.,
                                Instrument Detection Limit, Method
                                Detection Limit, Estimated Detection
                                Limit).

[[Page 23452]]

 
17. Detection Level Unit of    The unit of measure to express the
 Measure.                       concentration, count, or other value of
                                a contaminant level for the detection
                                level reported. (e.g., g/L,
                                colony forming units/mL (CFU/mL), etc.)
18. Analytical Precision.....  For purposes of the UCMR, Analytical
                                Precision is defined as the relative
                                percent difference (RPD) between spiked
                                matrix duplicates. The RPD for the
                                spiked matrix duplicates analyzed in the
                                same batch of samples as the analytical
                                result being reported is to be entered
                                in this field. Precision is calculated
                                as Relative Percent Difference (RPD)
                                between spiked matrix duplicates using,
                                RPD = [(X1-X2)/{(X1 + X2)/2}]  x  100.
19. Analytical Accuracy......  For purposes of the UCMR accuracy is
                                defined as the percent recovery of the
                                contaminant in the spiked matrix sample
                                analyzed in the same analytical batch as
                                the sample result being reported and
                                calculated using; % recovery = [(amt.
                                found in Sp--amt. found in sample) /
                                amt. spiked]  x  100.
20. Presence/Absence.........  Chemicals: Presence--a response was
                                produced by the analysis (i.e., greater
                                than or equal to the MDL but less than
                                the minimum reporting level)/Absence--no
                                response was produced by the analysis
                                (i.e., less than the MDL).
                               Microbiologicals: Presence--indicates a
                                response was produced by the analysis /
                                Absence--indicates no response was
                                produced by the analysis.
------------------------------------------------------------------------

    (e) How must I report this information? You must report this 
information in the electronic or other format specified by the primacy 
agency.
    (f) Can the laboratory to which I send samples report the results 
for me? Yes, as long as the laboratory sends you a copy for review and 
recordkeeping.
    3. Section 141.40 is revised to read as follows:


Sec. 141.40  Monitoring requirements for unregulated contaminants.

    (a) Requirements for owners and operators of public water 
systems.--(1) Do I have to monitor for unregulated contaminants?--(i) 
Transient systems. If you own or operate a transient non-community 
water system, you do not have to monitor for unregulated contaminants.
    (ii) Large systems. If you own or operate a public water system 
(other than a transient system) that serves more than 10,000 persons 
and do not purchase your entire water supply from another public water 
system, you must monitor as follows:
    (A) You must monitor for the unregulated contaminants on List 1 of 
the Unregulated Contaminant Monitoring List.
    (B) You must monitor for the unregulated contaminants on List 2 of 
the Unregulated Contaminant Monitoring List if notified by your State 
or EPA regional office that you are part of the screening survey.
    (C) You must monitor for the unregulated contaminants on List 3 of 
the Unregulated Contaminant Monitoring List if notified by your State 
or EPA regional office that you are part of the pre-screen testing.
    (iii) Small systems. If you own or operate a public water system 
(other than a transient system) that serves 10,000 persons or fewer and 
do not purchase your entire water supply from another public water 
system, you must monitor as follows:
    (A) You must monitor for the unregulated contaminants on List 1 of 
the Unregulated Contaminant Monitoring List if you are notified by your 
State or EPA regional office that you are part of the State Monitoring 
Plan for small systems.
    (B) You must monitor for the unregulated contaminants on List 2 of 
the Unregulated Contaminant Monitoring List if you are notified by your 
State or EPA regional office that you are part of the screening survey.
    (C) You must monitor for the unregulated contaminants on List 3 of 
the Unregulated Contaminant Monitoring List if you are notified by your 
State or EPA regional office that you are part of the pre-screen 
testing.
    (2) How would I be selected for the monitoring under the State 
Monitoring Plan, the screening survey, or the pre-screen testing?--(i) 
State Monitoring Plan. Only a representative sample of small systems 
must monitor for unregulated contaminants. EPA will select a national 
representative sample of small public water systems in each state 
through the use of a random number generator. Selection will be 
weighted by population served within each system water source type 
(surface or ground water) and system size category (systems serving 
persons numbering 25-500, 501-3,300, and 3,301-10,000). EPA will also 
select a small group of systems to be ``index sites.'' Systems selected 
as index sites provide information about their site and operation that 
will serve to allow extrapolation of their results to other systems of 
similar size, rather than collecting detailed information at every 
small system. Each State will have the opportunity to make some 
modifications to this selection. You will be notified by EPA or the 
State that your system is part of the final State Monitoring Plan.
    (ii) Screening Survey. The purpose of the screening survey is to 
determine the occurrence of contaminants in drinking water or sources 
of drinking water for which analytical methods have recently been 
developed for unregulated contaminant monitoring. EPA will select up to 
300 systems to participate in this survey by using a random number 
generator. You will be notified by EPA or the State that your system 
has been selected for monitoring under the screening survey.
    (iii) Pre-screen testing. The purpose of pre-screen testing is to 
determine the occurrence of contaminants for which EPA needs to 
determine that new analytical methods can measure their existence in 
locations most likely to be found. EPA will select up to 200 systems to 
participate in this testing considering the characteristics of the 
contaminants, precipitation, system operation, and environmental 
conditions. You will be notified by EPA or the State that your system 
has been selected for monitoring under the pre-screen testing program.
    (3) For which contaminants must I monitor? Lists 1, 2 and 3 of 
unregulated contaminants are as follows:

[[Page 23453]]



                                                    Table 1.--Unregulated Contaminant Monitoring List
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                              6--Date
           1--Contaminant             2--CAS Identification No.   3--Analytical  methods   4--Minimum reporting    5--Sampling  location   monitoring to
                                                                                                   level                                       begin
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                               List 1--Assessment Monitoring Organic Chemical Contaminants
--------------------------------------------------------------------------------------------------------------------------------------------------------
2,4-dinitrotoluene.................  121-14-2...................  EPA 525.2 a...........  2.4 ug/L e............  EPTDS f...............       2001-2003
2,6-dinitrotoluene.................  606-20-2...................  EPA 525.2 a...........  2.0 ug/L e............  EPTDS f...............       2001-2003
DCPA mono acid degradate...........  887-54-7...................  EPA 515.1 a...........  1.0 ug/L e............  EPTDS f...............       2001-2003
                                                                  EPA 515.2 a
                                                                  D5317-93 b
                                                                  AOAC 992.32 c
DCPA di acid degradate.............  2136-79-0..................  EPA 515.1 a...........  1.0 ug/L e............  EPTDS f...............       2001-2003
                                                                  EPA 515.2 a
                                                                  D5317-93 b
                                                                  AOAC 992.32 c
4,4'-DDE...........................  72-55-9....................  EPA 508 a.............  0.75 ug/L e...........  EPTDS f...............       2001-2003
                                                                  EPA 508.1 a
                                                                  EPA 525.2 a
                                                                  D5812-96 b
                                                                  AOAC 990.06 c
EPTC...............................  759-94-4...................  EPA 507 a.............  1.2 ug/L e............  EPTDS f...............       2001-2003
                                                                  EPA 525.2 a
                                                                  D5475-93 b
                                                                  AOAC 991.07 c
Molinate...........................  2212-67-1..................  EPA 507 a.............  0.87 ug/L e...........  EPTDS f...............       2001-2003
                                                                  EPA 525.2 a
                                                                  D5475-93 b
                                                                  AOAC 991.07 c
MTBE...............................  1634-04-4..................  EPA 524.2 a...........  5.0 ug/Lg.............  EPTDS f...............       2001-2003
                                                                  D5790-95 b
                                                                  SM6210Dd
Nitrobenzene.......................  98-95-3....................  EPA 524.2 a...........  12 ug/Lg..............  EPTDS f...............       2001-2003
                                                                  D5790-95 b
                                                                  SM6210Dd
Terbacil...........................  5902-51-2..................  EPA 507 a.............  23 ug/L e.............  EPTDS f...............       2001-2003
                                                                  EPA 525.2 a
                                                                  D5475-93 b
                                                                  AOAC 991.07 c
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                               List 1--Assessment Monitoring Microbiological Contaminants
--------------------------------------------------------------------------------------------------------------------------------------------------------
Aeromonas Hydrophila...............  Reserved...................  Membrane filter, in     1 colony forming unit.  (1) Near end of              2001-2003
                                                                   review.                                         distribution line
                                                                                                                   with longest
                                                                                                                   residence time; (2)
                                                                                                                   at a representative
                                                                                                                   site in the
                                                                                                                   distribution system.


----------------------------------------------------------------------------------------------------------------
                                    CAS         Anticipated        Minimum
    Chemical Contaminant      identification     analytical    reporting level      Sampling     Date monitoring
                                    No.           methods             e             location         to begin
----------------------------------------------------------------------------------------------------------------
    List 2.--Screening Survey: Organic Chemical Contaminants To Be Sampled After Notice of Analytical Methods
                                                  Availability
----------------------------------------------------------------------------------------------------------------
1,2-diphenylhydrazine.......        122-66-7  EPA 525.2 i....  Reserved h.....  EPTDS f........  Reserved.h
2-methyl-phenol.............         95-48-7  SPE/GC/MS l....  Reserved ......  EPTDS f........  Reserved.h
2,4-dichlorophenol..........        120-83-2  SPE/GC/MS l....  Reserved h.....  EPTDS f........  Reserved.h
2,4-dinitrophenol...........         51-28-5  SPE/GC/MS l....  Reserved. h....  EPTDS f........  Reserved.h
2,4,6 trichlorophenol.......         88-06-2  SPE/GC/MS l....  Reserved h.....  EPTDS f........  Reserved.h
Acetochlor..................      34256-82-1  EPA 525.2i.....  Reserved h.....  EPTDS f........  Reserved.h
Alachlor ESA................  ..............  TBD h..........  Reserved h.....  EPTDS f........  Reserved.h
Diazinon....................        333-41-5  EPA 525.2 k....  Reserved h.....  EPTDS f........  Reserved.h
Disulfoton..................        298-04-4  EPA 525.2k.....  Reserved h.....  EPTDSf.........  Reserved.h
Diuron......................        330-54-1  SPE/HPLC/U V j.  Reserved h.....  EPTDS f........  Reserved.h
Fonofos.....................        944-22-9  EPA 525.2 i....  Reserved h.....  EPTDS f........  Reserved.h
Linuron.....................        330-55-2  SPE/HPLC/U Vj..  Reserved h.....  EPTDS f........  Reserved.h
Prometon....................       1610-18-0  EPA 525.2k.....  Reserved h.....  EPTDS f........  Reserved.h
Terbufos....................      13071-79-9  EPA 525.2k.....  Reserved h.....  EPTDS f........  Reserved.h
----------------------------------------------------------------------------------------------------------------
References:

[[Page 23454]]

 
a The version of the EPA methods being approved will be dependant upon the status of the approval of new
  versions for compliance monitoring. If appropriate regulations approving new versions of EPA compliance
  monitoring methods are completed prior to the promulgation of this regulation, the following versions of the
  above methods will be approved. Methods for the Determination of Organic Compounds in Drinking Water--
  Supplement III, EPA-600/R-95-131, August 1995. NTIS PB95-261616. Copies are also available from the National
  Technical Information Service (NTIS), U.S. Department of Commerce, 5285 Port Royal Road, Springfield, Virginia
  22161. The toll-free number is 800-553-6847. If new regulations changing the versions of methods being
  approved for compliance monitoring are not completed prior to the promulgation of this regulation, then the
  following versions of the EPA methods are being approved for monitoring under the Unregulated Contaminant
  Monitoring Rule. Methods 507, 508, and 515.1 are in Methods for the Determination of Organic Compounds in
  Drinking Water, EPA-600/4-88-039, December 1988, Revised, July 1991. Methods 515.2 and 524.2 are in Methods
  for the Determination of Organic Compounds in Drinking Water--Supplement II, EPA/600/R-92/129, August 1992.
  These documents are available from the National Technical Information Service, (NTIS) U.S. Department of
  Commerce, 5285 Port Royal Road, Springfield, Virginia 22161 (800) 553-6847. Methods 508.1 and 525.2 are
  available from US EPA NERL-Cincinnati, Cincinnati, Ohio 45268, (513) 569-7586.
b Annual Book of ASTM Standards, 1996 and 1998, Vol. 11.02, American Society for Testing and Materials. Method
  D5812-96 is located in the Annual Book of ASTM Standards, 1998, Vol. 11.02. Methods D5790-95, D5475-93, and
  D5317-93 are located in the Annual Book of ASTM Standards, 1996 and 1998, Vol 11.02. Copies may be obtained
  from the American Society for Testing and Materials, 101 Barr Harbor Drive, West Conshohocken, PA 19428.
c Official Methods of Analysis of AOAC (Association of Official Analytical Chemist) International, Sixteenth
  Edition, 4th Revision, 1998, Volume I, AOAC International, First Union National Bank Lockbox, PO Box 75198,
  Baltimore, MD 21275-5198. 1-800-379-2622.
d 18th and 19th editions of Standard Methods for the Examination of Water and Wastewater, 1992 and 1995,
  American Public Health Association; either edition may be used. Copies may be obtained from the American
  Public Health Association, 1015 Fifteenth Street NW, Washington, DC 20005.
e Minimum Reporting Level determined by multiplying by 10 the least sensitive method's minimum detection limit
  (MDL=standard deviation times the Student's T value for 99% confidence level with n-1 degrees of freedom), or
  when available, multiplying by 5 the least sensitive method's estimated detection limit (where the EDL equals
  the concentration of compound yielding approximately a 5 to 1 signal to noise ratio or the calculated MDL,
  whichever is greater).
f Entry Points to the Distribution System, After Treatment, representing each water source in use over the
  twelve-month period of monitoring.
g Minimum Reporting Levels (MRL) for Volatile Organic Compounds (VOC) determined by multiplying either the
  published Method Detection Limit (MDL) or 0.5 ug/L times 10, whichever is greater. The MDL of 0.5 ug/L (0.0005
  mg/L) was selected to conform to VOC MDL requirements of 40 CFR 141.24(f)(17(E).
h To be Determined at a later time.
i Compound currently not listed as an contaminant in this method. Methods development currently being conducted
  in an attempt to add it to the scope of this method.
j Methods development currently in progress to develop a solid phase extraction/high performance liquid
  chromatography/ultraviolet method for the determination of this compound.
k Compound listed as being an contaminant using EPA Method 525.2; however, adequate sample preservation is not
  available. Preservation studies currently being conducted to develop adequate sample preservation.
l Methods development currently in progress to develop a solid phase extraction/gas chromatography/mass
  spectrometery method for the determination of this compound.


----------------------------------------------------------------------------------------------------------------
                                                                                            Date monitoring to
             Microorganism                 Identification No.       Sampling location              begin
----------------------------------------------------------------------------------------------------------------
 List 3.--Pre-Screen Testing: Contaminants with Analytical Methods Not Anticipated To Be Available by Regulation
                                                 Implementation
----------------------------------------------------------------------------------------------------------------
Cyanobacteria (blue-green algae, other  Reserved a.............  Reserved a.............  Reserved.a
 freshwater algae and their toxins)
Echoviruses...........................  Reserved a.............  Reserved a.............  Reserved.a
Coxsackieviruses......................  Reserved a.............  Reserved a.............  Reserved.a
Helicobacter pylori...................  Reserved a.............  Reserved a.............  Reserved.a
Microsporidia.........................  Reserved a.............  Reserved a.............  Reserved.a
Caliciviruses.........................  Reserved a.............  Reserved a.............  Reserved.a
Adenoviruses..........................  Reserved a.............  Reserved a.............  Reserved.a
----------------------------------------------------------------------------------------------------------------
a To be Determined at a later time

    (4) What general monitoring requirements must I follow for List 1 
monitoring?--(i) All systems. You must:
    (A) Collect samples of the listed contaminants in accordance with 
paragraph (e) of this section and any other specific instructions 
provided to you by EPA or the State;
    (B) Review the laboratory testing results to ensure reliability; 
and
    (C) Report the results as specified in Sec. 141.35.
    (ii) Large systems. In addition to paragraph (d)(1) of this 
section, you must arrange for testing of the samples according to the 
methods specified for each contaminant in the Unregulated Contaminant 
Monitoring List and in Appendix A to this section.
    (iii) Small systems. In addition to paragraph (d)(1) of this 
section, you must:
    (A) Properly receive, store and use the sampling equipment sent to 
you from the laboratory;
    (B) Sample at the times specified by the State or the EPA Regional 
office;
    (C) Collect and pack samples in accordance with the instructions 
sent to you by the laboratory; and
    (D) Send the samples to the laboratory designated by EPA.
    (5) What specific sampling and quality control requirements must I 
follow for monitoring of List 1 contaminants? (i) All systems. You must 
comply with the following requirements:
    (A) Sample collection and shipping time. If you must ship the 
samples for testing, you must collect the samples early enough in the 
day to allow adequate time to send the samples for overnight delivery 
to the laboratory since some samples must be processed at the 
laboratory within 30 hours of collection. You must not collect samples 
on Friday, Saturday or Sunday because sampling on these days would not 
allow samples to be shipped and received at the laboratory within 30 
hours.
    (B) No compositing of samples. You must not composite (that is, 
combine, mix or blend) the samples. You must collect, preserve and test 
each sample separately.
    (C) Review and reporting of results. After you have received the 
laboratory results, you must review and confirm the system information 
and data regarding sample collection and test results. You must report 
the results as provided in Sec. 141.35.
    (ii) Large systems. In addition to paragraph (e)(1) of this 
section, you must comply with the following:

[[Page 23455]]

    (A) Timeframe. You must collect the samples in one twelve-month 
period during the years indicated in column 6 of the Unregulated 
Contaminant Monitoring List.
    (B) Frequency. You must collect the samples according to the 
following frequency specified by contaminant type and water source 
type:

----------------------------------------------------------------------------------------------------------------
          Contaminant type              Water source type           Timeframe                 Frequency
----------------------------------------------------------------------------------------------------------------
Chemical...........................  Surface water.........  12 months.............  Every three months with one
                                                                                      sampling event during the
                                                                                      vulnerable time a.
                                     Ground water..........  12 months.............  Vulnerable time a and six
                                                                                      (6) months later.
Microbiological....................  Surface and ground      12 months.............  Vulnerable time a and six
                                      water.                                          (6) months later.
----------------------------------------------------------------------------------------------------------------
a Vulnerable time means May 1 through July 31, unless the State or EPA Regional Office informs you that it has
  selected a different time period as your system's vulnerable time.

    (C) Location. You must collect samples at the location specified 
for each listed contaminant in column 5 of the Unregulated Contaminant 
Monitoring List.
    (D) Sampling instructions. You must follow the sampling procedure 
for the method specified in column 3 of the Unregulated Contaminant 
Monitoring List for each contaminant.
    (E) Testing and analytical methods. You must use the analytical 
method specified for each listed contaminant in column 3 of the 
Unregulated Contaminant Monitoring List, the minimum reporting levels 
in column 4 of the Unregulated Contaminant Monitoring List, and the 
quality control procedures specified in appendix A to this section.
    (F) Sampling deviations. If you do not sample according to the 
procedures specified for a listed contaminant, you must resample 
following the procedures specified for the method.
    (G) Testing. You must arrange for the testing of the contaminants 
by a laboratory certified under Sec. 141.28.
    (iii) Small systems that are part of the State Monitoring Plan. In 
addition to paragraph (a)(5)(i) of this section, you must comply with 
the following:
    (A) Frequency. You must collect samples at the times specified for 
you by the State or EPA regional office, following the frequency 
specified in paragraph (a)(5)(ii)(B) of this section for the 
contaminant type and water source type.
    (B) Location. You must sample at the locations specified for you by 
the State or EPA regional office.
    (C) Sampling deviations. If you do not collect a sample according 
to the instructions provided to you, then you must report the deviation 
on the sample reporting form that you send to the laboratory with the 
samples.
    (D) Sample kits. You must store and maintain the sample collection 
kits sent to you by the laboratory in a secure place until used for 
sampling. If indicated in the kit's instructions, you must freeze the 
cold packs. The sample kit will include all necessary containers, 
packing materials and cold packs, instructions for collecting the 
sample and sample treatment (such as dechlorination or preservation), 
report forms for each sample, contact name and telephone number for the 
laboratory, and a prepaid return shipping docket and return address 
label. If any of the materials listed in the kit's instructions are not 
included or arrive damaged, you must notify the laboratory which sent 
you the sample collection kits.
    (E) Sampling instructions. You must comply with the instructions 
sent to you by the State or EPA Regional office concerning use of 
containers, collection (how to fill the sample bottle), dechlorination 
and/or preservation, and sealing and preparing the sample and shipping 
containers for shipment. You must also comply with the instructions 
sent to you by the laboratory concerning the handling of sample 
containers for specific contaminants.
    (F) Duplicate samples. EPA will select systems in the State 
Monitoring Plan that must collect duplicate samples for quality 
control. If your system is selected, you will receive two sample kits 
that you must use. You must use the same sampling protocols for both 
sets of samples, following the instructions in the duplicate sample 
kit.
    (G) Sampling forms. You must completely fill out the sampling forms 
sent to you by the laboratory, including the data elements 1 through 9 
listed in Sec. 141.35 for each sample. You must sign and date the 
sampling forms.
    (H) Sample submission. Once you have collected the samples and 
completely filled in the sampling forms, you must send the samples and 
the sampling forms to the laboratory designated in your instructions.
    (6) What additional requirements must I follow if my system is 
selected as an Index site? If your system is selected as an index site 
in the State Monitoring Plan, you must assist EPA or the State in 
identifying appropriate sampling locations and provide information on 
which wells and intakes are in use at the time of sampling, well casing 
and screen depths (if known) for those wells, and the pumping rate of 
each well or intake at the time of sampling.
    (7) What must I do if my system is selected for the screening 
survey or pre-screen testing?--(i) Large systems. If your system serves 
over 10,000 persons, you must collect and arrange for testing of the 
contaminants in List 2 and List 3 of the unregulated contaminant 
monitoring list in accordance with the requirements set out in 
paragraph (a)(4) and (5) of this section. You must send the samples to 
one of the laboratories designated by EPA in your notification. You 
must report the test results to the State.
    (ii) Small systems. If your system serves 10,000 persons or fewer, 
you must collect samples in accordance with the instructions sent to 
you by the State or EPA, or, if informed by the State or EPA that the 
State or EPA will collect the sample, you must assist the State or EPA 
in identifying the appropriate sampling locations and in taking the 
samples. EPA will report the test results to you and the State.
    (b) Requirements for State and Tribal Participation--(1) How can I 
as the director of a State or Tribal drinking water program participate 
in the State Monitoring Plan and Screening Survey for small systems? 
You may participate in the selection of systems for the State 
Monitoring Plan and the timing of monitoring as follows:
    (i) Initial plan. EPA will first specify the number of systems 
serving 10,000 or fewer persons by water source and size in an initial 
plan for each State using a random number generator. EPA will also 
generate a replacement list of systems for systems that may not have 
been correctly specified on the initial plan. This initial plan will 
also indicate the week, month, and year that each system must monitor 
for the contaminants in List 1 of the

[[Page 23456]]

Unregulated Contaminant Monitoring List. EPA will provide you with the 
initial plan for your State or Tribe, including systems to be index 
sites and those small systems to be part of the screening survey.
    (ii) State acceptance or modification of the list of systems. 
Within 60 days of receiving the initial plan, you may notify EPA that 
you either accept it as your State Monitoring Plan or request to modify 
the initial plan by removing systems closed, merged or purchasing water 
from another system. In place of any such systems, you must use systems 
from the replacement list in the order listed. Your request must 
include the modified plan and the reason for replacement of systems. 
You may also specify an alternative week, month and year in which the 
monitoring is to occur for each system in the State Plan as long as 
approximately one-third of the systems in the State Plan must monitor 
in each year specified in Table 1, column 6. This monitoring may be 
coordinated with regulated contaminant compliance monitoring at your 
discretion.
    (iii) State modification of the timing of monitoring. Within 60 
days of receiving the initial plan, you may also modify the plan by 
selecting an alternative week, month and year for monitoring for each 
system in the State Monitoring Plan as long as approximately one-third 
of the systems in the Plan monitor in each year specified in column 6 
of the Unregulated Contaminant Monitoring List. This monitoring may be 
coordinated with regulated contaminant compliance monitoring at your 
discretion. You must send the modified plan to EPA.
    (iv) Determination of alternate vulnerable time. Within 60 days of 
receiving the initial plan, you may also determine that the most 
vulnerable time of the year for any or all of the systems is different 
than the May 1 through July 31. If you make this determination, you 
must modify the State Monitoring Plan to indicate the alternate 
vulnerable time and to which systems the alternate vulnerable time 
applies. You must also notify the system(s) of the most vulnerable time 
of the year that you have specified for them to sample for one of their 
sampling events. You must notify them at least 90 days before their 
first unregulated contaminant sampling is to occur.
    (v) Notification of systems. If you decide to accept or modify the 
initial plan, you must provide to EPA your plan for notifying each 
public water system of its selection for the plan and instructions for 
monitoring. You must provide notification to systems at least 90 days 
before sampling must occur.
    (vi) No modification. If you do not accept the initial plan or 
submit a request to EPA to modify the initial plan within 60 days, the 
initial plan will become the State Monitoring Plan for your State or 
Tribe. In that case, you may still notify each public water system of 
its selection for the plan and instructions for monitoring as long as 
you notify EPA that you will be undertaking this responsibility.
    (2) What instructions do I provide to systems that are part of the 
State Monitoring Plan? If you choose to notify systems that they are 
part of the State Monitoring Plan, you must send a monitoring schedule 
to each system listed in the State Monitoring Plan and instructions on 
location, frequency, timing of sampling, use of sampling equipment, and 
handling and shipment of samples based on these regulations. EPA will 
provide you with guidance for these instructions.
    (3) Can I also change the vulnerable time for monitoring of large 
systems? Yes. If you desire to change the vulnerable time for 
monitoring at large systems, then not later than 120 days prior that 
monitoring, you must send written notification to the EPA Regional 
Office indicating your State is modifying the most vulnerable time of 
the year for any or all of the large systems to be different than the 
period of May 1 through July 31 and specify the vulnerable time for 
each system to which any modification applies. You must also notify the 
system(s) of the most vulnerable time of the year that you have 
specified for them to sample for one of their sampling events. You must 
notify them at least 90 days before their first unregulated contaminant 
sampling is to occur.
    (4) How can I participate in monitoring for the Screening Survey 
for large systems? Within 120 days prior to sampling, EPA will notify 
you which systems have been selected to participate in the screening 
survey, the sampling dates, the designated laboratory for testing, and 
instructions for sampling. You may choose to notify the selected 
systems in your State of these screening survey requirements. If you 
choose to do so, you must notify EPA within 30 days of EPA's 
notification to you. You must provide the necessary screening survey 
information to the selected systems at least 90 days prior to the 
sampling date.
    (5) How can I participate in monitoring for Pre-Screen Testing? You 
can participate in pre-screen testing in two ways.
    (i) First, within 60 days of EPA's letter to you concerning 
initiation of Pre-screen testing for specific contaminants, you can 
identify from 5 up to 25 systems in your State that you determine to be 
representative of the most vulnerable systems to these contaminants, 
modify your State Monitoring Plan to include these most vulnerable 
systems, and notify the EPA Regional Office of the addition of these 
systems to the State Plan. These systems must be selected from all 
community and non-transient noncommunity water systems. EPA will use 
the State-identified vulnerable systems to select up to 200 systems 
nationally to be monitored considering the characteristics of the 
contaminants, precipitation, system operation, and environmental 
conditions.
    (ii) Second, within 120 days prior to sampling, EPA will notify you 
which systems have been selected, sampling dates, the designated 
laboratory for testing of samples for systems serving 10,000 or fewer 
persons and approved laboratories for systems serving more than 10,000 
persons, and instructions for sampling. You may choose to notify the 
owner or operator of the selected systems in your State of these pre-
screen testing requirements. If you choose to do so, you must notify 
EPA within 30 days of EPA's notification to you. You must provide the 
necessary pre-screen testing information to the owner or operator at 
least 90 days prior to the sampling date.
    (6) Can I add contaminants to the Unregulated Contaminant 
Monitoring List? Yes, the SDWA allows Governors of seven or more States 
to petition the EPA Administrator to add one or more contaminants to 
the Unregulated Contaminant Monitoring List. The petition must clearly 
identify the reason for adding the contaminant(s) to the monitoring 
list, including the potential risk to public health, particularly any 
information that might be available regarding disproportional risks to 
the health and safety of children, the expected occurrence documented 
by any available data, any analytical methods known or proposed to be 
used to test for the contaminant(s), and any other information that 
could assist the Administrator in determining which contaminants 
present the greatest public health concern and should, therefore, be 
included on the Unregulated Contaminant Monitoring List.
    (7) Can I waive monitoring requirements? Only with EPA approval and 
under very limited conditions. Following are the procedures for 
requesting the only type of waiver available under these regulations.

[[Page 23457]]

    (i) You may apply to EPA for a state-wide waiver from the 
monitoring requirements for public water systems serving more than 
10,000 persons. To apply for such a waiver, you must submit an 
application to EPA that includes the following information:
    (A) The list of contaminants on the Unregulated Contaminant List 
for which you request a waiver, and
    (B) Documentation demonstrating, for each contaminant in your 
request, that during the past 15 years it has not been used, stored, 
disposed of, released, naturally present or detected in the source 
waters or distribution systems in the State.
    (ii) EPA will notify you if EPA determines that you may waive 
monitoring requirements.

Appendix A to Sec. 141.40--Quality Control Requirements for Testing 
All Samples Collected

    Your system must ensure that the quality control requirements 
listed below for testing of samples collected and submitted under 
Sec. 141.40 are followed:
    (1) Sample Collection/Preservation. Follow the sample collection 
and preservation requirements for the specified method for each of 
the contaminants in Table 1. These requirements specify sample 
containers, collection, dechlorination, preservation, storage, 
sample holding time, and extract storage and/or holding time that 
the laboratory must follow. Samples with methods that specify 
storage at 4 deg.C must be shipped in ice or frozen gel packs.
    (2) Method Detection Limit. Calculate the laboratory method 
detection limit (MDLs) for each contaminant in Table 1, List 1, 
using the appropriate specified method according to procedures in 40 
CFR part 136, appendix B with the exception that the contaminant 
concentration used to fortify reagent water must be less than or 
equal to the minimum reporting level (MRL) for the contaminants as 
specified in Table 1 of Sec. 141.40(a)(3). The calculated MDL is 
equal to the standard deviation times the Student's T value for 99% 
confidence level with n-1 degrees of freedom. (The MDL must be less 
than or equal to one-half of the MRL.)
    (3) Calibration. Perform a three to six point initial 
calibration depending on the method utilized. Calibration must be 
verified initially with a low-level standard at a concentration 
within 10% of the MRL for each contaminant. Perform a 
continuing calibration verification following every 10th sample. The 
calibration verification must be performed by alternating low-level 
and mid-level calibration standards. The low-level standard is 
defined as a concentration within 10% of the MRL with an 
acceptance range of 40%. The mid-level standard is in 
the middle of the calibration range with an acceptance range of 
20%.
    (4) Reagent Blank Analysis. Analyze one laboratory reagent 
(method) blank per sample set/batch that is treated exactly as a 
sample. The maximum allowable background concentration is one-half 
of the MRL for all contaminants. A field reagent blank is required 
only for EPA Method 524.2 (or equivalent listed methods, D5790.95 
and SM6210D).
    (5) Quality Control Sample. Obtain a quality control sample from 
an external source to check laboratory performance at least once 
each quarter.
    (6) Matrix Spike and Duplicate. Prepare and analyze matrix spike 
(MS) for accuracy and matrix spike duplicate (MSD) samples for 
precision to determine method accuracy and precision for all 
contaminants in Table 1, List 1. MS/MSD samples must be prepared and 
analyzed at a frequency of 5% (or one MS/MSD set per every 20 
samples) or with each sample batch whichever is more frequent. In 
addition, the MS/MSD spike concentrations must be alternated between 
a low-level spike and mid-level spike approximately 50% of the time. 
(For example: a set of 40 samples will require preparation and 
analysis of two MS/MSD sets. The first set must be spiked at either 
the low-level or mid level, and the second set must be spiked with 
the other standard, either the low-level or mid-level whichever was 
not used for the initial MS/MSD set). The low-level MS/MSD spike 
concentration must be within 10% of the MRL for each 
contaminant. The mid-level MS/MSD spike concentration must be within 
10% of the mid level calibration standard for each 
contaminant. There are no acceptance criteria specified for MS/MSD 
recoveries.
    (7) Internal Standard Calibration. As appropriate to a method's 
requirements to be used, test and obtain an internal standard for 
the methods for each chemical contaminant in Table 1, List 1, a pure 
contaminant of known concentration, for calibration and quantitation 
purposes. The methods specify the percent recovery or response that 
you must obtain for acceptance.
    (8) Method Performance Test. As appropriate to a method's 
requirements to be used, test for surrogate compounds, a pure 
contaminant unlikely to be found in any sample, to monitor method 
performance. The methods specify the percent recovery that you must 
obtain for acceptance.
    (9) Detection Confirmation. Confirm any chemical contaminant 
detected above the MRL by gas chromatographic/mass spectrometric 
(GC/MS) methods. If testing resulted in first analyzing the sample 
extracts via specified gas chromatographic methods, an initial 
confirmation by a second column dissimilar to the primary column may 
be performed. If the contaminant detection is confirmed by the 
secondary column, then the contaminant must be reconfirmed by GC/MS 
using 3 specified ion peaks for contaminant identification. Use one 
of the following confirming techniques: (i) perform single point 
calibration of the GC/MS system for confirmation purposes only as 
long as the calibration standard is at a concentration within 
 50% of the concentration determined by the initial 
analysis; or (ii) perform a three point calibration with single 
point daily calibration verification of the GC/MS system regardless 
of whether that verification standard concentration is within 
 50% of sample response. If GC/MS analysis confirms the 
initial contaminant detection, report results determined from the 
initial analysis.
    (10) Reporting. Report the analytical results and other data, 
with the required data listed in Sec. 141.35, Table 1. Report this 
data electronically to the State or EPA Regional Office, unless the 
State or EPA Regional Office specifies otherwise. Systems must 
coordinate with their laboratories for electronic reporting to the 
State or EPA Regional Office to ensure proper formatting and timely 
data submission.

PART 142--NATIONAL PRIMARY DRINKING WATER REGULATIONS 
IMPLEMENTATION

    1. The authority citation for part 142 continues to read as 
follows:

    Authority: 42 U.S.C. 300f, 300g-1, 300g-2, 300g-3, 300g-4, 300g-
5, 300g-6, 300j-4, 300j-9, and 300j-11.

    2. Section 142.15 is amended by revising paragraph (c)(3) to read 
as follows:


Sec. 142.15  Reports by States.

* * * * *
    (c) * * *
    (3) Unregulated contaminant monitoring. The State must report the 
results from the unregulated contaminant monitoring required under 40 
CFR 141.40, including the information identified in 40 CFR 141.35(b) to 
the National Drinking Water Contaminant Occurrence Data Base. This 
report must be in an electronic format and sent to EPA through the Safe 
Drinking Water Information System or other information system specified 
by the Agency not later than the quarter following receipt of the 
unregulated contaminant monitoring results from the public water system 
or its laboratory.
* * * * *
    3. Section 142.16 is amended by revising paragraphs (e) 
introductory text, (e)(1) introductory text, and (e)(1)(i)(C) to read 
as follows:


Sec. 142.16  Special primacy requirements.

* * * * *
    (e) An application for approval of a State program revision which 
adopts the requirements specified in 40 CFR 141.11, 141.23, 141.32, 
141.61 and 141.62 must contain the following (in addition to the 
general primacy requirements enumerated elsewhere in this part, 
including the requirement that State regulations be at least as 
stringent as the federal requirements):
    (1) If a State chooses to issue waivers from the monitoring 
requirements in 40 CFR 141.23 and 141.24, the State shall describe the 
procedures and criteria which it will use to review waiver applications 
and issue waiver determinations.

[[Page 23458]]

    (i) * * *
    (C) The State decision criteria, including the factors that will be 
considered in deciding to grant or deny waivers. The decision criteria 
must include the factors specified in 40 CFR 141.24(f)(8) and 
141.24(h)(6).
* * * * *
[FR Doc. 99-10001 Filed 4-29-99; 8:45 am]
BILLING CODE 6560-50-P