[Federal Register Volume 61, Number 63 (Monday, April 1, 1996)]
[Proposed Rules]
[Pages 14280-14284]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-7745]



=======================================================================
-----------------------------------------------------------------------

ENVIRONMENTAL PROTECTION AGENCY

40 CFR PART 300

[FRL-5448-8]


National Oil and Hazardous Substances Pollution Contingency Plan; 
National Priorities List

AGENCY: Environmental Protection Agency.

ACTION: Notice of intent to delete the Washington County landfill from 
the National Priorities List; request for comments.

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

SUMMARY: The United States Environmental Protection Agency (U.S.

[[Page 14281]]
EPA) Region 5 announces its intent to delete the Washington County 
Landfill Superfund Site from the National Priorities List (NPL) and 
requests public comment on this action. The NPL constitutes Appendix B 
of 40 CFR part 300 which is the National Oil and Hazardous Substances 
Pollution Contingency Plan (NCP), which U.S. EPA promulgated pursuant 
to section 105 of the Comprehensive Environmental Response, 
Compensation, and Liability Act of 1980 (CERCLA) as amended. This 
action is being taken by U.S. EPA, because it has been determined that 
fund-financed responses under CERCLA have been implemented and U.S. 
EPA, in consultation with the State of Minnesota, has determined that 
no further response under CERCLA is necessary. U.S. EPA and the State 
have determined that remedial activities conducted at the Site to date 
have been protective of public health, welfare, and the environment. In 
addition, based on the results of a five-year review of the remedial 
action completed in January 1994, the existing remedy is being upgraded 
to improve long-term protectiveness. The State of Minnesota will 
undertake any further response actions that may be necessary, using 
funds provided under the Minnesota Landfill Cleanup Law.

DATES: Comments concerning the proposed deletion of the Site from the 
NPL may be submitted on or before May 1, 1996.

ADDRESSES: Comments may be mailed to Gladys Beard (SR-6J) Associate 
Remedial Project Manager, Superfund Division, U.S. EPA, Region 5, 77 W. 
Jackson Blvd. (SR-6J), Chicago, IL 60604. Comprehensive information on 
the site is available at U.S. EPA's Region 5 office and at the local 
information repository located at: Minnesota Pollution Control Agency 
Public Library, 520 Lafayette Rd., St. Paul, MN 55155-4194. Requests 
for comprehensive copies of documents should be directed formally to 
the Region 5 Docket Office. The address and phone number for the 
Regional Docket Officer is Jan Pfundheller (SMR-7J), U.S. EPA, Region 
5, 77 W. Jackson Blvd., Chicago, IL 60604, (312) 353-5821.

FOR FURTHER INFORMATION CONTACT: Lawrence Schmitt, Remedial Project 
Manager at (312) 353-6565, Gladys Beard (SR-6J) Associate Remedial 
Project Manager, Superfund Division, U.S. EPA, Region 5, 77 W. Jackson 
Blvd., Chicago, IL 60604, (312) 886-7253 or Don de Blasio (P-19J), 
Office of Public Affairs, U.S. EPA, Region 5, 77 W. Jackson Blvd., 
Chicago, IL 60604, (312) 886-4360.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Introduction
II. NPL Deletion Criteria
III. Deletion Procedures
IV. Basis for Intended Site Deletion

I. Introduction

    The U.S. Environmental Protection Agency (EPA) Region 5 announces 
its intent to delete the Washington County Landfill Site from the 
National Priorities List (NPL), which constitutes Appendix B of the 
National Oil and Hazardous Substances Pollution Contingency Plan (NCP), 
and requests comments on the proposed deletion. The EPA identifies 
sites that appear to present a significant risk to public health, 
welfare, or the environment, and maintains the NPL as the list of those 
sites. Sites on the NPL may be the subject of remedial actions financed 
by the Hazardous Substance Superfund Response Trust Fund (Fund). 
Pursuant to Section 300.425(e)(3) of the NCP, any site deleted from the 
NPL remains eligible for fund-financed remedial actions if the 
conditions at the site warrant such action.
    The U.S. EPA will accept comments on this proposal for thirty (30) 
days after publication of this notice in the Federal Register.
    Section II of this notice explains the criteria for deleting sites 
from the NPL. Section III discusses procedures that EPA is using for 
this action. Section IV discusses the history of this site and explains 
how the site meets the deletion criteria.
    Deletion of sites from the NPL does not itself create, alter, or 
revoke any individual's rights or obligations. Furthermore, deletion 
from the NPL does not in any way alter U.S. EPA's right to take 
enforcement actions, as appropriate. The NPL is designed primarily for 
informational purposes and to assist in Agency management.

II. NPL Deletion Criteria

    The NCP establishes the criteria the Agency uses to delete Sites 
from the NPL. In accordance with 40 CFR 300.425(e), sites may be 
deleted from the NPL where no further response is appropriate. In 
making this determination, U.S. EPA will consider, in consultation with 
the State, whether any of the following criteria have been met:
    (I) Responsible parties or other persons have implemented all 
appropriate response actions required; or
    (ii) All appropriate fund-financed responses under CERCLA have been 
implemented, and no further response action by responsible parties is 
appropriate; or
    (iii) The Remedial investigation has shown that the release poses 
no significant threat to public health or the environment and, 
therefore, remedial measures are not appropriate.

III. Deletion Procedures

    Upon determination that at least one of the criteria described in 
300.425(e) has been met, U.S. EPA may formally begin deletion 
procedures once the State has concurred. This Federal Register notice, 
and a concurrent notice in the local newspaper in the vicinity of the 
Site, announce the initiation of a 30-day comment period. The public is 
asked to comment on U.S. EPA's intention to delete the Site from the 
NPL. All critical documents needed to evaluate U.S. EPA's decision are 
included in the local information repository and the deletion docket.
    Upon completion of the public comment period, the U.S. EPA Regional 
Office will prepare a Responsiveness Summary to evaluate and address 
each significant comment that was received. The public is welcome to 
contact the U.S. EPA Region 5 Office to obtain a copy of this 
responsiveness summary. If U.S. EPA then determines the deletion from 
the NPL is appropriate, final notice of deletion will be published in 
the Federal Register.

IV. Basis for Intended Site Deletion

    The Washington County Landfill site is located within the city 
limits of Lake Elmo in Washington County, Minnesota. Lake Elmo is 
approximately nine miles northeast of St. Paul. The site occupies a 110 
acre parcel, and the landfill covers 40 acres of the site. The area 
adjacent to the site is predominantly residential with a small amount 
of farming. Residences are directly adjacent to the site on the north, 
west, and south. There is a city park to the east of the site. 
Approximately 3000 people reside within a three mile radius of the 
site. A recreational lake, Lake Jane, is located 250 feet north of the 
site.
    The landfill is located in a gently sloping area and is underlain 
by sand and gravel deposits. Ground water flow in the sand and gravel 
aquifer below the site is generally to the south away from Lake Jane. 
The site was extensively mined for sand and gravel prior to its use as 
a sanitary landfill during the years 1969 through 1975. The landfill 
was operated jointly by Washington and Ramsey Counties (``the 
Counties''), which accepted approximately 2.6

[[Page 14282]]
million cubic yards of solid waste. The solid waste is estimated to be 
73% residential waste, 26% commercial waste, and 1% demolition waste.
    Following landfill closure, ground water at the site was found to 
contain elevated levels of organic and inorganic substances in wells on 
and off-site, including residential wells. Volatile organic compounds 
(VOCs) found in residential wells were the most serious concern. The 
site was proposed for the NPL July 8, 1983. The listing was finalized 
in September 21, 1984, 49 FR 37070.

Operable Unit 1

    Remedial planning activities began under the authority of the 
Minnesota Pollution Control Agency (MPCA) prior to finalization of the 
site on the National Priorities List. In 1982, MPCA requested that the 
Counties begin investigating the need for remedial action at the site.
    On October 24, 1984, the Counties and MPCA signed a Response Order 
by Consent which required the following:
    Installation and operation of a ground water gradient control 
system, which captured contaminated ground water and prevented further 
movement of contaminants off-site;
    Installation and operation of a spray irrigation system for VOCs in 
the captured ground water;
    Monitoring of the landfill and area ground water to ensure the 
effectiveness of the gradient control system and the protection of 
residential wells; and
    Provision of safe drinking water supplies to residents whose 
private wells contained substances in excess of Minnesota private 
drinking water well criteria. An interim water supply was required 
immediately upon effect of the Order and a permanent supply was to be 
developed.
    Construction of monitoring wells, a gradient control well, and the 
air stripping system was accomplished in sequence with the Phase I thru 
Phase IV investigations during 1982 and 1983. The gradient control 
system began full operations on December 12, 1983. The system consisted 
of one gradient control well near the southwest corner of the landfill, 
designed to extract 200 gallons per minute, and a spray irrigation area 
in the southeast portion of the site. The spray irrigation area 
consisted of an area of 1.9 acres with sandy soils. This area was 
believed to be contained within the capture zone of the gradient 
control system. Twenty-seven monitoring wells were installed and an 
additional 25 residential wells were being monitored for the presence 
of contaminants.
    The Phase V report in February 1984 provided the first evaluation 
of the performance of the system. Regular evaluations, modifications, 
and improvements to the system continued after 1984. During that time, 
the gradient control system was expanded to include 4 wells capable of 
extracting a maximum of 400 gallons per minute, berms were constructed 
and other improvements were made to increase infiltration of treated 
ground water at the treatment area, and an off-site discharge was added 
for some extracted ground water. A backup treatment area was added and 
used while the primary treatment area was down for maintenance. The 
backup treatment area is not currently in use. Finally, the number of 
monitoring wells was expanded to 38.
    The interim alternative water supply consisted of bottled water for 
4 residences, which was implemented immediately after the Response 
Order was effective in 1984. Planning for a permanent water supply for 
affected residents resulted in the report: ``Long Term Drinking Water 
Supply Plan for Washington County Sanitary Landfill No. 1'' dated 
October 1985. On July 7, 1986, MPCA issued a Minnesota Enforcement 
Decision Document (MEDD) which approved the use of activated carbon 
filters for the residences with drinking water well advisories issued 
by the Minnesota Department of Health. The activated carbon filters for 
the 4 affected residences were installed immediately after the MEDD was 
effective in 1986.
    Operable Unit 1 is a containment remedy, with treatment of the 
extracted ground water. The reports provided by the Counties documented 
the results of regular sampling of monitoring wells and residential 
wells, which indicated that the gradient control system adequately 
contained the ground water contamination on site. Remedial action 
implementation for Operable Unit 1 ground water and drinking water 
measures was conducted by the Counties under MPCA authority and 
oversight prior to the issuance of U.S. EPA's Unilateral Administrative 
Order on January 16, 1992. U.S. EPA's Unilateral Administrative Order 
required the Counties to continue the implementation of MPCA's previous 
requirements. Under the requirements of MPCA's terminated Response 
Order by Consent, there were no cleanup levels or termination 
provisions for this operable unit at the site.
    Quality Assurance/Quality Control (QA/QC) measures for ground water 
sampling and analysis were specified in MPCA's Response Order by 
Consent. U.S. EPA adopted these same measures in its Order. QA/QC for 
all other activities was monitored by MPCA, and all documentation is 
contained in correspondence between the Counties and MPCA or in 
internal MPCA memos and reports.
    In September 1992, a soil gas survey conducted at the site by the 
MPCA discovered explosive levels of landfill gases in soils at the 
western boundary of the site. After further investigation confirmed 
that there was significant off-site migration of explosive gases, U.S. 
EPA issued a First Amended Unilateral Administrative Order on February 
17, 1993. This Order required the Counties to control landfill gas 
migration so that explosive levels are not exceeded at the property 
boundary.
    A barrier extraction vent system was constructed along the west 
side of the landfill to intercept migrating gases; this system was 
completed in December 1993. The system consisted of 11 extraction vents 
connected to a blower system. The gas control system effectively 
controlled gas migration from the western portion of the site 
immediately. The mixture of air and landfill gases collected by the 
system was found to be safe for discharge to the atmosphere without 
treatment. Off-site areas which contained elevated levels of explosive 
gas in soils were monitored and gas levels were found to slowly 
dissipate. Monitoring of basements in nearby residences for gas 
accumulation was initiated shortly after discovery of the gas, and no 
exceedences of safe levels occurred.
    Remedial action implementation for Operable Unit 1 explosive gas 
control measures was conducted by the Counties under U.S. EPA authority 
and MPCA oversight. QA/QC measures for landfill gas sampling and 
analysis were specified in the approved work plans. U.S. EPA approved a 
Remedial Action Report documenting the QA/QC for completion of 
construction activities for explosive gas control in March 1995. This 
report describes the activities completed pursuant to the First Amended 
Unilateral Administrative Order.

Operable Unit 2

    Based on the results of residential well sampling conducted during 
1988 and 1989, MPCA requested the Minnesota Department of Health (MDH) 
to reassess the health risks to residents. As a result, the MDH issued 
drinking water well advisories to 10 residences. MPCA subsequently 
requested the Counties to re-evaluate the long-term drinking water 
supply needs of affected residences. The Counties submitted the report 
``Long-Term Drinking Water Supply Plan, Washington County

[[Page 14283]]
Sanitary Landfill No. 1'' dated June 30, 1990. This report constitutes 
the Remedial Investigation/Feasibility Study for Operable Unit 2. MPCA 
executed a Record of Decision (ROD) requiring the construction of a 
public water supply system to serve the 10 residences on September 27, 
1990. U.S. EPA concurred with this ROD on November 15, 1990.
    Although not required by the ROD, the Counties elected to provide 
the alternate water supply to 73 additional residences within a service 
area which surrounds the site. The service area was developed to 
include all residences which might possibly be affected by the site. 
The additional work also includes the abandonment and sealing of 68 
residential wells within the service area, since continued use of these 
could possibly contribute to further movement of contaminants away from 
the site. Construction of the water supply system was initiated in June 
1991 and connection of the 10 residences with drinking water advisories 
to the system was completed in December 1991. Connection of 72 of the 
remaining 73 residences was completed by June 1992.
    A Remedial Action Report dated September 1992 documents 
construction activities for Operable Unit 2. The report describes both 
the activities required by the ROD and the additional work performed by 
the Counties in order to increase the protectiveness of the remedy.
    Community relations activities conducted by MPCA for Operable Unit 
2 began on July 27, 1990, when the RI/FS and Proposed Plan were 
released to the public. The documents were placed in an information 
repository at the Lake Elmo Branch of the Washington County Public 
Library, 3459 Lake Elmo Avenue, Lake Elmo, MN and notices published in 
local newspapers. A public comment period was open from July 31, 1990 
thru August 31, 1990, and a public meeting was held on August 14, 1990. 
A responsiveness summary was included with the ROD.
    Remedial action implementation for Operable Unit 2 was conducted by 
the Counties under MPCA authority and oversight. The MDH reviewed plans 
and specifications for the installation of the public water supply 
system and the sealing of residential wells. Documentation of QA/QC for 
this operable unit is contained in the Remedial Action Report.
    Operable Unit 2 is an alternate water supply, and there are no 
cleanup levels for this activity. The Remedial Action Report documents 
that the system was properly installed and tested, and is functioning. 
The water supply system is connected to the City of Oakdale's 
distribution system. Lake Elmo and Oakdale are jointly responsible for 
maintaining the distribution system and assuring the quality of the 
drinking water delivered to the residents. Operable Unit 2 is completed 
and there are no operation and maintainance (O&M) requirements for the 
alternate water supply system. Responsibility for routine operation of 
the water supply system has been assumed by the local municipalities.
    The QA/QC program utilized throughout this remedial action has been 
sufficiently rigorous and adequately complied with to enable the 
determination by U.S. EPA that all activities have been correctly 
carried out and all results accurately reported. U.S. EPA is thereby 
assured of the satisfactory execution of the remedial action consistent 
with MPCA's Response Order by Consent, MEDD, and Record of Decision, as 
well as U.S. EPA's 1992 and 1993 Unilateral Administrative Orders.

Five-Year Review

    Hazardous substances will remain on-site above levels that will 
allow unrestricted use and unrestricted exposure, and CERCLA Section 
121 provides that reviews will be performed every five years for 
remedial actions which result in hazardous substances, pollutants, or 
contaminants remaining at the site above levels that allow for 
unlimited use and unrestricted exposure. The first Five-Year Review was 
completed in January 1994. U.S. EPA and MPCA concluded that the remedy 
has been reasonably effective in limiting further uncontrolled releases 
of contaminants to the environment. However, the inadequacies 
documented in the review indicated the need for modifications to the 
remedy. The remedy was not found to be sufficiently protective of human 
health and the environment and as operated unlikely to be cost-
effective for the long-term. Specific recommendations follow:

Long-Term Water Supply

    U.S. EPA and MPCA recommended that the long-term water supply 
system remedy continue as it currently exists. The public water supply 
along with well abandonment continued to provide an alternative safe, 
long-term source of water to the owners of residences near the landfill 
who were issued drinking water well advisories by the State.

Ground Water Remedial Action

    The long-term need for a ground water remedial action was found to 
be related to recommendations for closure and post-closure as described 
below. A final landfill cover combined with a long-term landfill gas 
extraction and treatment system, if necessary, would reduce long-term 
reliance on the current gradient control well and treatment system. 
However, in the short-term, a ground water gradient control well and 
treatment system would continue to be necessary at the Site. The need 
for a gradient control system should be evaluated at least on an annual 
basis.
    U.S. EPA and MPCA recommended that the ground water and treatment 
system be modified to utilize either an air stripper or granular 
activated carbon filtration system prior to spray irrigation. Winter 
spraying will be halted and storage capacity of effluent will be 
provided if the effluent cannot be properly treated.

Ground Water Monitoring Well Network

    U.S. EPA and MPCA recommended that the existing ground water and 
ground water monitoring plan used to evaluate the performance of the 
system be maintained, with the addition of several monitoring wells.

Landfill Closure and Post-Closure Requirements

    U.S. EPA and MPCA recommended that a final landfill cover be 
installed to current MPCA standards. A final landfill cover should 
limit infiltration of precipitation into the fill and help to reduce 
leachate production. The reduction of leachate should in turn reduce 
the amount of loading to ground water at the landfill site. Reduction 
of the moisture in the fill should also help to reduce the 
bacteriological activity in the fill, thus reducing the rate of methane 
production.

Minnesota Landfill Cleanup Law

    In 1994, the Legislature of the State of Minnesota enacted the 
Landfill Cleanup Law, Minnesota Laws 1994, ch. 639, codified at 
Minnesota Stat. Sec. Sec. 115B.39 to 115B.46 (the Act), authorizing the 
Commissioner of the MPCA to assume responsibility for future 
environmental response actions at qualified landfills that have 
received notices of compliance from the Commissioner. Additionally, the 
Act established funds to enable the MPCA to perform all necessary 
response, operation, and maintenance at such landfills.
    A notice of compliance was issued by MPCA for the Washington County 
Landfill Site on November 21, 1995. MPCA has since assumed all 
responsibility for the Washington County Landfill under the Act. This 
includes operating the ground water gradient control and gas control 
systems

[[Page 14284]]
as well as the implementation of the recommendations of the Five-Year 
Review. Therefore, no further response actions under CERCLA are 
appropriate at this time. Consequently, U.S. EPA proposes to delete the 
site from the NPL.

    Dated: March 18, 1996.
David A. Ullrich,
Acting Regional Administrator, U.S. EPA, Region 5.
[FR Doc. 96-7745 Filed 3-29-96; 8:45 am]
BILLING CODE 6560-50-P