PB98-963143
EPA 541-R98-155
March 1999
EPA Superfund
Record of Decision Amendment:
Woodstock Municipal LF
Woodstock, IL
7/15/1998
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U.S. EPA SUPERFUND
RECORD OF DECISION AMENDMENT
WOODSTOCK MUNICIPAL LANDFILL SUPERFUND SITE
WOODSTOCK, MCHENRY COUNTY, ILLINOIS
JULY 1998
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TABLE OF CONTENTS
DECLARATION FOR THE RECORD OF DECISION AMENDMENT i
RECORD OF DECISION AMENDMENT SUMMARY
I. SITE NAME, LOCATION, AND DESCRIPTION 1
II. SITE HISTORY AND ENFORCEMENT ACTIVITIES 2
III. REASON FOR ROD AMENDMENT 6
IV. HIGHLIGHTS OF COMMUNITY PARTICIPATION 7
V. SCOPE AND ROLE OF SELECTED REMEDY 8
VI. SUMMARY OF SITE CHARACTERISTICS 9
VII. EFFECT OF PDI DATA ON REMEDY SELECTION 15
VIII. SUMMARY OF SITE RISKS 21
IX. DESCRIPTION OF ALTERNATIVES 23
X. COMPARATIVE EVALUATION OF ALTERNATIVES 27
XI. DESCRIPTION OF SELECTED REMEDY 34
XII. STATUTORY DETERMINATION 36
FIGURES
APPENDICES
APPENDIX A - RESPONSIVENESS SUMMARY
APPENDIX B - ADMINISTRATIVE RECORD
Woodstock ROD Amendment
July 1998
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RECORD OF DECISION AMENDMENT
SELECTED REMEDIAL ALTERNATIVE
DECLARATION
SITE NAME AND LOCATION
Woodstock Municipal Landfill Superfimd Site (the Site); Woodstock, McHenry County, Illinois
STATEMENT OF BASIS AND PURPOSE
This decision document represents the United States Environmental Protection Agency's (U.S.
EPA) selected final remedial action for the Site located in Woodstock, Illinois. This decision
document was developed in accordance with the Comprehensive Environmental Response,
Compensation and Liability Act of 1980 (CERCLA), as amended by the Superfund Amendments
and Reauthorization Act of 1986 (SARA), and to the extent practicable, with the National Oil
and Hazardous Substances Contingency Plan (NCP). The decisions contained herein are based
on information contained in the Administrative Record for this Site. The Illinois Environmental
Protection Agency (IEPA) is expected to concur with the selected remedy.
ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from the site, if not addressed by
implementing the response action selected in this Record of Decision (ROD) Amendment, may
present an imminent and substantial endangerment to public health, welfare, or the environment.
DESCRIPTION OF THE REMEDY
The U.S. EPA, in consultation with the IEPA, is modifying the landfill cap profile, and the
requirement to construct a groundwater pump-and-treat system to address residual vinyl chloride
conta...aiatic in the up,... water-bearing unit, downi radient of the landf This remedy is
intended to be the final action for the site, and addresses all contaminated media, including:
contaminated soil, sediment, and groundwater, landfilled wastes, leachate generation and
emission of landfill gases. The major components of the selected remedy include:
o Excavation and consolidation of contaminated sediments and sludges under the landfill
cap:
o Installation and maintenance of a geosynthetic landfill cap in compliance with the
specifications set forth in this ROD Amendment:
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July 1998 ii
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o Installation and maintenance of a landfill gas venting system that is compatible with the
type of cap specified in this ROD Amendment;
o Installation and operation of a groundwater extraction, treatment, and discharge system as
a contingent component of the remedy, required only if natural attenuation of the vinyl
chloride plume does not occur at a rate and to the degree acceptable under state and
federal law;
o Development and implementation of a comprehensive monitoring program to ensure the
effectiveness of the remedy;
o Mitigation of wetland areas where contaminated sediment removal occurs;
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o Mitigation of wetland damage or loss during or after remedial activities arc complete;
o Development and implementation of a surface water and sedimentation control system;
o Implementation of institutional controls to limit land and groundwater use.
The following remedial actions from the June 30, 1993, ROD remain in full force and effect:
Fencing; Contaminated soil/sediment excavation and consolidation; Landfill gas collection
system; Well monitoring and remedy monitoring programs; Institutional controls; Correction of
work deficiencies; and Wetland mitigation.
STATUTORY DETERMINATIONS
The final selected remedy is protective of human health and the environment, complies with
Federal and State requirements that are legally applicable or relevant and appropriate to the
remedial action, and is cost-effective. This remedy utilizes permanent solutions and alternative
treatment technologies to the maximum extent practicable and satisfies the statutory preference
for remedies which employ treatment that reduce toxicity, mobility, or volume as a principal
element. Be*, .ase t..is iv...edy may result in hazardoi s substances remaii...ig on oite above
health-based levels, a review will be conducted at least every five years after commencement of
the remedial action to ensure that the remedy continues to provide adequate protection of human
health and the environment.
William E. Muno
Director, Superfund Division
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SUMMARY OF REMEDIAL ALTERNATIVE SELECTION
WOODSTOCK MUNICIPAL LANDFILL
WOODSTOCK, ILLINOIS
I. SITE NAME. LOCATION AND DESCRIPTION
The Woodstock Municipal Landfill Superfund Site (the Site) is
located on the south side of the city of Woodstock (the City),
McHenry County, Illinois, a municipality with a population of
approximately 16,179 residents. The Site is located south of
Davis Road, southwest of the intersection of U.S. Route 14 and
Illinois Route 47 and is shown on Figure I. The coordinates for
the Site are northeast quarter of Section 17. Township 44 North,
Range 7 East (NE 1/4, Se 17, T44N, R7E).
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The land surrounding the Site is a mixture of residential,
agricultural, wetlands, commercial, and light industrial use.
Land use immediately north of the Site is primarily residential
and agricultural. Land use west of the Site is semi-agricultural
with much of the land currently classified as a wetland.
Wetlands are also located adjacent to the Site on the east. The
Kishwaukee River runs along the southwestern perimeter of the
Site. The City's wastewater treatment plant and additional
wetlands are located south of the Site.
The Site geology consists of a complex sequence of unconsolidated
glacial deposits which are approximately 200 feet thick. These
deposits have been divided into four units; an upper sand and
gravel aquifer, an intermediate clay till member, a lower clay
till member, and a sand unit which overlies bedrock comprised of
dolomite and shale.
It is important to note that the State of Illinois has designated
the glacial and bedrock aquifers underlying the Site as Class I
aquifers. A Class I designation signifies that the groundwater
is either currently being used or has the potential to be used as
a drinkir"~ wate^ -.ource, regardless of municipal "" ^nd use or
zoning restrictions.
Surface water runoff at the Site is generally to the west and
south and is confined by drainage to the wetlands and subsequent
infiltration or overland flow into the Kishwaukee River.
The nearest residents to the Site are located approximately 500
feet north of the Site. The principal threat at the Site is a
plume of vinyl chloride contamination, which originates at the
landfill and migrates to adjacent wetlands associated with the
Kishwaukee River. The nearest existing residential well which
may potentially be impacted by the .contaminated groundwater if
further migration occurs is located approximately 2500 feet
southwest of the Site. Based on data collected during the
remedial investigation (RI), the Predesign Investigation (PDI),
and subsequent groundwater and surface water monitoring at the
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Site, groundwater contamination has not migraie'd to the local
residential wells used for drinking water. The majority of the
residents in the City are provided water through a municipal
drinking water supply system. This system is not considered to
be threatened by the Site.
II. SITE HISTORY AND ENFORCEMENT ACTIVITIES
The landfill had a number of different owners between 1935, when
it was first used as a trash dump and open burning area, and when
it was covered and classified as closed by the Illinois
Environmental Protection Agency (IEPA) in October 1980. The
current owner of the landfill property is the City.
Between approximately 1940 and 1958, William Gaulke operated the
Site as a local trash dump ?nd open burning area. Beginning in
1958, the Site was used by the City under -\ lease agreement with
Mr. Gaulke as a household garbage and municipal landfill. The
City purchased the property in 1968, and commenced using it for
the disposal of household and municipal solid waste and various
industrial solid wastes, including waste paint and coating
materials, plating wastes, solvents, waste metals, inks and
drummed material including polychlorinafced biphenyls (PCBs). In
addition, the City allowed Woodstock Die Casting Inc., an Allied
Signal subsidiary, to dispose of approximately 7200 cubic yards
of waste sludge at the landfill.
The IEPA filed a complaint against the City in 1972 regarding
operation of the landfill. The Illinois Pollution Control Board
(IPCB) issued an opinion finding that open dumping, liquid
deposition without approval, failure to follow set guidelines,
and operating without a permit. The City was ordered to cease
and desist all violations, and to obtain the necessary permits.
During this same time period, the IEPA requested the installation
of a leachate collection system to address releases from the
landfill. However, no system was installed and a waiver was
granted by the IPCB based on the City's stated intent to close
the _ ^nc j.11 in the near future and be_ause the leachaf •> did not
violate surface water standards at the time. The City
discontinued disposal activities at the Site in 1975 and closed
the landfill by covering it with fill material. Numerous
inspections were conducted at the Site by the IEPA from 1975-
1980. The IEPA continually notified the City during this time
that, although the landfill was no longer accepting waste and was
considered closed, the final cover was deficient. In 1980, the
IEPA classified the Site as closed and covered. In 1983, the
City was granted a permit from the IEPA to landfarm municipal
sewage sludge at the Site. A second permit was issued by the
IEPA in July 1988, but sludge application was discontinued prior
to that date, so the later permit was not used.
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During a July 1988 sampling investigation by ''the United States
Environmental Protection Agency (U.S. EPA or Agency), residential
wells located downgradient of the landfill were sampled and found
to contain arsenic, selenium, and thallium in excess of the Safe
Drinking Water Act maximum drinking water levels. A subsequent
sampling investigation in December 1988 again detected these
substances in the same wells, but the concentrations did not
exceed the regulatory criteria.
National Priorities List
Based on the results of the U.S. EPA and the IEPA investigations
and taking into account such factors as populations at risk, the
potential of hazardous substances being present, the potential
for contamination of drinking water supplies and the potential
destruction of sensitive ecosystems, the Site was proposed to be
placed on the National Priorities List (NPL) in June 1988. The
Site was placed final on the NPL in Octobei 1989.
June 30, 1993, Record of Decision
In 1989, the U.S. EPA identified several potentially responsible
parties for the Site. In 1989, three of the potentially
responsible parties agreed, pursuant to an Administrative Order
on Consent (AOC), to investigate the nature and extent of
contamination at the Site and to evaluate the most effective
methods to clean up the Site. Two of the potentially responsible
parties (hereinafter the PRP Group) actually performed the work
required by the AOC. By June 1993, the PRP Group had completed
the remedial investigation (RI) and feasibility study (FS).
However, the U.S. EPA never approved the FS. On June 30, 1993, a
Record of Decision (ROD) was signed for the Site that addressed
all contaminated media, including contaminated soil, sediment,
and groundwater; landfilled wastes; leachate generation; and
emission of landfill gases. The two major components of the
selected remedy required: (1) the installation and maintenance
of a geosynthetic landfill cap in compliance with Title 35
Illinois Administrative Code (IAC), Subtitle G, Chapter 1,
Subchapter I: Sr^d Waste and Special Waste waulr'^g, Part
811.314; and (2) installation and operation ^ a yroundwater
extraction, treatment, and discharge (pump-and-treat) system to
remediate a groundwater contaminant plume containing vinyl
chloride. Because negotiations for a Remedial Design/Remedial
Action (RD/RA) Consent Decree were unsuccessful, the U.S. EPA
issued a Unilateral Administrative Order (UAO) for RD/RA on
September 2, 1994.
Institutional Controls
The UAO, Section VII, Paragraph 35 required land use restrictions
to ensure that the physical and structural integrity of the cap
and its components were not compromised. According to the
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information submitted by the PRPs, the following actions have
been taken:
o On September 17, 1991, the City passed Resolution No. 635
which prohibits location of wells of any kind, other than
wells approved by the U.S. EPA and the IEPA as part of the
site remediation and monitoring, and provides that no
residential use or structure of any kind shall be located or
built upon or constructed in or on the property which was
formerly used as the City of Woodstock landfill. This
restriction has been recorded in the Office of the Recorder
of Deeds and is specified to be permanent.
o On January 7, 1997, the City passed Ordinance No. 2659 which
reclassifies the property which was fqrmerly used as the
City of Woodstock landfill, from a R1S residential district
to a M2 General Manufacturing District.
By letter dated April 27, 1997, the U.S. EPA queried whether
Resolution No. 635 prohibited the construction of only
residential structures or structures of any kind. This issue has
not yet been fully resolved.
Predesign Investigation
Pursuant to the terms of the UAO, the PRP Group performed a PDI
and Interim Monitoring Program (IMP). The report of the findings
for the PDI, entitled Predesign Investigation Report Woodstock
Municipal Landfill Site, Woodstock, Illinois (August 1996), was
approved by the U.S. EPA on August 1, 1996.
Additional tasks performed during the PDI to further characterize
the Site included: performing a full topographic survey of the
Site; advancing numerous soil borings to determine the extent and
thickness of the waste deposits and cover soils; evaluation of
landfill gas; and further hydrogeologic characterization which
included installation of additional monitoring wells, piezometers
and tn e .raction wel-, performance of an aquifer -ump .ng test
and collection of additional rounds of groundwater, surface water
and sediment samples at the Site. Collectively, these post-ROD
studies resulted in the PRP Group, the U.S. EPA and the IEPA
obtaining a significantly more thorough understanding of
site-specific conditions.
One of the more important findings of the PDI is that the
landfill's impact on groundwater appears to be less than the
RI/FS data would have indicated. RI sampling results established
that contamination in the landfill had no significant impact on
the deeper aquifer zones at the Site. Groundwater in the upper
unit, however, was found to contain contamination. The
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contaminant of concern in the upper water-bea_fing unit
downgradient of the landfill is vinyl chloride. Receptors of
groundwater discharge from the upper water-bearing unit include
the Kishwaukee River and the we-.lands areas present immediately
west and south of the landfill.
The PDI demonstrated that the vinyl chloride contamination in
groundwater is restricted to a limited area, smaller than the
area estimated during the RI. In addition, groundwater
monitoring activities performed since the RI have suggested that
the concentrations of vinyl chloride appear to be declining, and
that the vinyl chloride plume appears to be stagnant (not
moving). It is important to note, however, that although the
concentrations of vinyl chloride present at the Site are lower
than those detected during the RI, the levels of vinyl chloride
present at the Site still remain above the federal maximum
contaminant level (MCL) . Moreover, it liar not yet been
demonstrated to the satisfaction of the U.?. EPA, that the trend
in vinyl chloride concentrations will continue to decrease over
time in a predictable manner.
Petition for an ESD and ROD Amendment
In October 1996, the PRP Group petitioned the U.S. EPA for an
Explanation of Significant Differences (BSD) to delay the design1
and implementation of the groundwater pump-and-treat system based
on data obtained during the PDI and the quarterly monitoring
events. However, the U.S. EPA could not grant the ESD for the
delay of the groundwater pump-and-treat system, without an
adequate landfill cap in place.
In addition to reducing the potential risk posed by exposure to
landfill contaminants, capping the landfill would reduce
precipitation infiltration through the landfill, thereby reducing
leachate generation. Ground water contaminant loading, leachate
generation, and seepage into the wetlands would then be reduced
or eliminated. The U.S. EPA also had determined that construction
of a drainage layer above the barrier layer was necessary to
ensure - .ag-term protection of human health and tne en.xronment.
An efficient drainage layer with a hydraulic conductivity greater
than 1 X 10'1 cm/sec, would virtually eliminate standing water in
the protective layer, thus eliminating infiltration through the
barrier layer. Also, the Agency felt that a gas venting system
would reduce potential risks due to the landfill gases. For all
of the above reasons, the U.S. EPA denied the ESD Petition unless
and until it appeared likely that the PRP Group would comply with
the landfill cap construction requirements of the UAO.
In a document dated August 1, 1997, the PRP Group petitioned the
U.S. EPA Region 5 for a ROD Amendment seeking the following
modifications to the original ROD for the Site: (1) the
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identification of 35 IAC 807 as the applicable *or relevant and
appropriate requirement (ARAR) for the landfill cap; and (2)
deletion of the requirement for an active pump-and-treat
groundwater collection and treatnent system. In other words, the
PRP Group renewed its efforts to have the pump-and-treat system
deleted as a requirement of the selected remedy for the Site, and
further sought to construct a landfill cap that complied with the
landfill cap standard in effect at the time the landfill was
closed, rather than the standard in effect at the time of
signature of the original ROD.
The U.S. EPA, in consultation with the IEPA, began to evaluate
whether, in light of the PDI data, the landfill cap component of
the originally-selected remedy could be modified in a way that
resulted in significant cost savings for the PRP Group, but
remained protective of human health and the' environment. The
U.S. EPA and the IEPA technical and legal, representatives met on
several occasions to discuss potential new parameters for a
modified landfill cap.
III. REASON FOR ROD AMENDMENT
The June 30, 1993, ROD remedy included the following elements:
A) Fencing; B) Contaminated soil/sediment excavation and
consolidation; C) Capping; D) Groundwater remediation and
treatment system; E) Landfill gas collection system; F) Well
monitoring and remedy monitoring programs; G) Institutional
controls; H) Predesign, additional and supplemental
investigations and studies; I) Correction of work deficiencies;
and J) Wetland mitigation. The two most significant components
of the original remedy required the construction of a cap that
met or exceeded the requirements of Title 35 of the IAC Section
811.314 and the construction of a groundwater pump-and-treat
system.
Based upon the results of the PDI, it appears that the landfill's
impact- on groundwater is less than the RI/FS data would have
indicated. The PDI demonstrated that the vinyl chloride
contamination in groundwater is restricted to a limited area,
smaller than the area estimated during the RI. In addition,
groundwater monitoring activities performed since the RI have
suggested that the concentrations of vinyl chloride appear to be
declining, and that the vinyl chloride plume appears to be
stagnant (not moving). It is important to note, however, that
although the concentrations of vinyl chloride present at the Site
are lower than those detected during the RI, the levels of vinyl
chloride present at the Site still remain above the federal
maximum contaminant level (MCL). Moreover, it has not yet been
demonstrated to the satisfaction of the U.S. EPA, that the trend
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in vinyl chloride concentrations will continue to decrease over
time in a predictable manner.
As a result of the PDI, comments received from interested
persons, and the U.S. EPA's growing expertise with regard to
landfills and contaminated groundwater, the Agency decided to
amend the original ROD. The U.S. EPA issued a Proposed Plan for
an Amendment to the 1993 ROD, which identified the U.S. EPA's
proposed revisions to the original ROD and described the proposed
new cleanup remedy for remediating the Site. The Proposed Plan
was available for public review and comment from February 23,
1998, through April 8, 1998. The Proposed Plan was required by
Section 117 (a) of the Comprehensive Environmental Response,
Compensation and Liability Act(CERCLA or Superfund), as amended
by the Superfund Amendments and Reauthorization Act (SARA) of
1986. The U.S. EPA held a public meeting'on March 4, 1998, to
accept comments from residents and other individuals interested
in the Site.
Previous investigations and design reports, as well as any other
pertinent documents in the Administrative Record and Information
Repositories, should be consulted for in-depth details on the
U.S. EPA's development and evaluation of the proposed revisions
to the cleanup remedy.
IV. HIGHLIGHTS OF COMMUNITY PARTICIPATION
Compliance with the public participation requirements of Section
113 (k) (2) (B) (I-v) of the CERCLA, as amended by SARA, have been
achieved for the Site by:
o A Site information repository was established at the
Woodstock Public Library to allow local access to Site-
related documents;
o The Site Administrative Record has been updated to include
the Propose^1 Plan for a ROD Amendment and otu°r documents
relied upon ror this ROD Amendment, and has j^een placed in
the Site information repository;
o A formal advertisement announcing the commencement of the
public comment period, the availability of the proposed
plan, and the time and place of the public meeting was
placed in the Northwest Herald and the Woodstock Independent
on February 25, 1998, local papers of general circulation;
o The Proposed Plan for a ROD Amendment was released for
public comment and placed into the Administrative Record on
February 23, 1998;
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o A thirty (30) day comment period was established and
scheduled to end on March 24, 1998;
o A public meeting was held on March 4, 1998, at the Woodstock
Public Library at which the U.S. EPA presented the Proposed
Plan to the community and received verbal comments. A
transcript was kept of the public meeting and was made
available to the public and placed in the Administrative
Record and Site repositories;
o The U.S. EPA granted a fifteen (IS) day extension of the
public comment period on March 4, 199"8, extending the
closing date to April 8, 1998;
o An advertisement was placed in the Northwest Herald on
March 20, 1998, and in the Woodstock Independent on
March 25, 1998, announcing the extension of the public
comment period to April 8, 1998;
o The U.S. EPA has received oral and written comments
regarding the. Proposed Plan for a ROD Amendment. Comments
have been addressed in the attached Responsiveness Summary
(Appendix A).
This ROD Amendment will become part of the Administrative Record
pursuant to the National Oil and Hazardous Substances Contingency
Plan (NCP), Section 300.825(a) (2) . The Administrative Record can
be found at the Site repositories located at:
1) Woodstock Public Library
414 West Judd Street
Woodstock, Illinois 60098
2) U.S. EPA Region 5 Records Center
Ralph H. Metcalfe Building, 7th Floor
77 West Jackson Boulevard
Chicago, Illinois 60604-3590
V. SCOPE AND ROLE OF THE SELECTED REMEDY
This ROD Amendment modifies only two components of the original
ROD: the landfill cap and pump-and-treat requirements. A
landfill cap still must be constructed at the Site, but the
components of that cap have been revised in a way that results in
significant costs savings. It is possible that the pump-and-
treat system required by the original ROD may still need to be
constructed in order to remediate the contaminated groundwater at
the Site, but this ROD Amendment makes this component of the
original remedy contingent on future data results.
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The U.S. EPA estimates the cost of a landfill/'cap constructed in
accordance with this ROD Amendment to be approximately $4.5-
million, a significant savings over the estimated cost of the
landfill cap required by the original ROD (~$6.2-million,
adjusted for 1998 costs and dollars). If groundwater data to be
collected at the Site during the next several years establishes
that no pump-and-treat system is necessary, additional cost
savings of approximately $800,000 will be realized. The U.S.
EPA's decision regarding the necessity for a pump-and-treat
system will depend on whether the groundwater plume is naturally
attenuating at a rate and to the degree acceptable under state
and federal law.
The following remedial actions from the June 30, 1993, ROD remain
part of the final remedy for the Site: (A) fencing; (B)
contaminated soil/sediment excavation and1consolidation; (E) .
landfill gas collection system; (F) well monitorir.g and remedy
monitoring programs; (G) institutional controls; (I; correction
of work deficiencies; and (J) wetland mitigation.
VI. SUMMARY OF SITE CHARACTERISTICS
The RI was conducted by the PRP'c contractor, Warzyn, and was
initiated in July 1990. The investigation was completed in June
1992, when the Final RI Report was issued. The RI identified the
types of contaminants that are migrating from the landfill, and
assessed the potential impact of contaminant migration on human •
health and the environment. The key conclusions which may be
surmised from this data are as follows:
o Groundwater contamination was detected in the upper aquifer
immediately southwest and downgradient of the landfill. The
contaminant of concern, vinyl chloride, was detected at
concentrations that exceed the MCL of 2 ppb for this
compound.
o Contamination was detected in leachate gas samples and in
leacnate groundwater samples collected from wells on the
landfill. The contaminants included volatile organics such
as benzene, ethylbenzene, toluene and xylene. In addition,
inorganic contaminants such as arsenic, barium, chromium,
lead and mercury were also detected in excess of regulatory
criteria. The leachate was also identified as the source of
contamination that is adversely affecting the groundwater,
surface water and sediments at the Site.
o Contamination was detected in surface soils, surface water,
and sediments at the Site. These three media were
contaminated with a wide range of volatile organic compounds
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(VOCs) , semi-volatile organic compounds J'SVOCs) , and
inorganic compounds.
o Leachate generation, if not controlled, will continue to
cause further releases to the impacted media and surrounding
wetlands and result in further adverse environmental
impacts. While the wetlands are currently limiting the full
impact of the landfill releases to the environment through
attenuation, the capacity and capability of the wetlands to
function in such a manner is limited.
As noted above, following the ROD, the PRPs performed an
extensive PDI and IMP under the UAO. Consequently, a more
extensive database was developed to supplement the existing RI
data. The PDI and IMP data suggests that the vinyl chloride
contamination in groundwater is restricted' to a limited area and
that concentration levels may be declining. However,
conjentration levels of vinyl chloride still exceed federal and
state cleanup levels. Moreover, it has not yet been demonstrated
to the satisfaction of the U.S. EPA, that the trend in vinyl
chloride concentrations will continue to decrease over time in a
predictable manner.
During the RI, sampling results indicated no impact to the deeper
groundwater zones at the Site. Groundwater in the upper unit was
the only groundwater found to contain contamination. Further
groundwater sampling performed during the PDI indicated the
following with respect to groundwater quality in the upper
water-bearing unit:
o Benzene and vinyl chloride were the only VOCs to exceed the
primary MCLs or the Illinois Class I Standard. Benzene
exceeded the MCL sporadically at only one monitoring well
location. Only vinyl chloride was found to consistently
exceed the applicable MCL or Class I Standards. Vinyl
chloride exceedences occurred at two monitoring wells
located downgradient of the Site. The vinyl chloride
concentrations downgradient of the landfill appear to have
decreased by approximately one-third since the RI.
o SVOCs, pesticides and PCBs were not contaminants of concern
in groundwater.
o Six target analyte list (TAL) metals were found to exceed
applicable groundwater quality criteria. Five of the six
exceedences were found to occur rarely and were not
indicative of landfill-related impacts to groundwater. Only
one of these six TAL metals, namely iron, was found to
regularly exceed applicable groundwater quality criteria.
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However, iron is not considered a health- risk and since
these exceedences occurred at both upgradient and
downgradient locations, it may be attributable, at least in
part, to natural groundwater chemistry.
o As a result, vinyl chloride appears to be the only
contaminant of concern in the upper water-bearing unit
downgradient of- the landfill. The Kishwaukee River and
associated wetlands, located immediately west and south of
the landfill, are ecological receptors of groundwater
discharged from the upper water-bearing unit.
Summary of Existing Hydrogeologic Data
During the RI, groundwater under the Site was observed within an
upper water table aquifer and within sand'seams in the lower till
units. Groundwater flow in the upper water-bearing zone was
generally observed to be towards the south/southwest and
calculated hydraulic gradients in the upper water-bearing zone
ranged from 0.0034 to 0.0167 feet per foot across the Site.
Receptors for groundwater discharge from the upper water bearing
unit include the Kishwaukee River and the wetlands areas present
to the west and south of the Site. Downgradient of the landfill,
the upper water-bearing zo'ne is overlain by peat deposited in the
wetland area. These groundwater flow patterns were confirmed and-
refined during the PDI.
Groundwater Flux and Surface Water Infiltration
During the RI, the water balance for the landfill was evaluated
to derive an estimate of groundwater contribution to surface
water discharge of the Kishwaukee River and surrounding wetlands.
The results of this evaluation indicated that total groundwater
discharge to surface water downgradient of the Site was
approximately 30,000 gallons per day.
The HELP Model simulation was used during the RI to obtain an
estimate of surface water infiltration through the existing
landfill -over. ~"he HELP model prev".icted that s\ -face water
infiltration over the landfill amounts to approximately seven
inches per year. During the PDI, detailed field studies more
accurately defined the thickness and areal extent of the upper
water-bearing unit and hydrogeologic parameters such as hydraulic
conductivity. The groundwater mass flux along the downgradient
portion (western and southwestern boundaries) of the landfill was
calculated using borehole and hydrogeologic data developed during
the PDI. The cross-sectional area of the upper aquifer was
determined through borehole logs, and hydrogeological parameters
such as hydraulic conductivity were obtained from pumping test
data developed during the PDI. Based upon the data developed
during the PDI and IMP, the U.S. EPA has concluded that the total
groundwater flux appears to be less than was calculated during
Woodstock ROD Amendment
July 1998 1;L
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the RI. The groundwater pumping test conducted during the PDI
also confirmed that the groundwater flux to the wetlands south
and west of the Site is considerably less than projected during
the RI. It was determined that the maximum sustainable pumping
rate was approximately five gallons per minute. This pumping
rate is one-tenth the rate projected during the RI/FS when the
groundwater pump-and-treat remedy was evaluated. During the
72-hour pump test conducted during the PDI, groundwater was
extracted from the upper water-bearing unit at an average rate of
5 gallons per minute (approximately 7,200 gallons per day).
Pumping the upper water-bearing unit at this rate over a 72-hour
period resulted in drawdown along the entire southern and
southwestern boundary of the landfill, confirming that the
groundwater flux of the vinyl chloride plume was much less than
the average pumping rate. ' ,
In summary, based upon the data developed during the PDI and IMP,
the post-ROD data demonstrates that the groundwater flux in the
shallow aquifer beneath the Site to the Kishwaukee River, and
associated wetlands to the south and west, is less than the
volume projected during the RI. The rate of surface water
infiltration also appears to be less than determined during the
RI. This finding is important because infiltration is directly
related to leachate generation. The leachate generation rate of
the landfill, based upon the PDI and the revised HELP model runs,
may be much lower than originally believed. Since contaminants
may be transported from the landfill through the migration of
leachate, the amount of contamination potentially flushed from
the landfill also may be less than originally believed. Given
the revised leachate generation rates and the concomitant
reduction in the potential for contaminant mobilization, an
active groundwater pump-and-treat system may no longer be
warranted, and a natural attenuation remedy may be more
appropriate.
Existing Landfill Cover
During the PDI, 64 soil borings were advanced on the landfill to
determir the hickne. s of the cover Boring logs compiled fron.
this much more plentiful database indicates that the cover
material consists primarily of silty clay. The average cover
thickness encountered during the PDI was 2.7 feet, but ranged
from 0.4 feet to 6.0 feet.
HELP Model Estimates of Surface Water Infiltration
The surface water infiltration estimate produced during the RI (7
inches per year) was obtained using a hydraulic conductivity (k)
value of 1.5 x 10"3 centimeter per second (cm/s) for the cover
soil, a value more than four orders of magnitude higher than the
laboratory-determined k values of two cover soil samples, and (2)
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an average annual precipitation of 36 inches ^instead of the 32
inches reported in.a soil survey report for McHenry County
published in 1965. Use of the greater k value and average annual
precipitation rate values probably inflated the surface water
infiltration estimates produced by the HELP model during the RI.
Although the HELP model estimate obtained during the RI can be
challenged because the rationale for using a k value of
1.5 x 10"3 cm/s is not clear, the HELP model estimate obtained by
the PRP Group using the laboratory-determined k values is
questionable for two reasons. First, a k value obtained from two
soil samples cannot be considered representative of the k value
of the soil cover spanning an area of over 43 acres. Second, a
laboratory-determined k value can represent the k value of small
soil samples tested in the laboratory, but it cannot represent
the k value of the landfill cover as a whola.
Moreover, it must be noted that the existing cover contains
numerous macropores such as shrinkage and freeze-thaw cracks,
root holes, and worm holes that can significantly increase
infiltration through the cover but that are not represented in
small soil samples collected for laboratory testing. As revealed
by a preliminary investigation of macropores visible on the
surface of the existing cover at the Site conducted by the U.S.
EPA on April 23, 1997, various types of macropores exist in the
cover soil, but their impact on surface water infiltration
through the existing cover cannot be estimated using the HELP
model or any other existing model. The U.S. EPA's observations,
however, led the Agency to conclude that the current cap has
deteriorated so significantly that it is ineffective in
preventing infiltration,
Considering (1) the lack of information regarding the degree of
compaction of existing cover soils; (2) the absence of
specifications regarding compaction of cover soils in 35 IAC 807,
the standard under which the existing cap was constructed; and
(3) _nat the existing landfill cap has been subject to repeated
wet/dry and freeze/thaw cycles since its initial installation in
1980, it is reasonable to assume that the existing cover consists
of relatively uncompacted soils.
In the HELP model, the default k value for uncompacted silty clay
is 4.2 x 10"5 cm/s, use of which produces a surface water
infiltration estimate of 4.46 inches per year. This infiltration
estimate is based on the HELP model's assumption that leakage
through cover soil occurs because of leakage through soil
micropores only. However, this assumption is probably not valid
because surface-connected macropores are known to conduct large
quantities of water through soil. Considering the HELP model
Woodstock ROD Amendment
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infiltration estimate of 4.46 inches per year_ in light of the
potential impact of the macropores existing in the 2.7-foot-thick
soil cover at the Site, the actual infiltration through the
existing cover, although impossible to estimate accurately using
any existing model, is likely to be closer to the RI estimate of .
7 inches per year than the 1.. 9 inches.
Extent of Vinyl Chloride Contamination
During the RI, vinyl chloride was detected at concentrations
exceeding the .primary MCLs in groundwater samples collected from
two monitoring wells (MW-4d and MW-8) located downgradient of the
landfill. The concentration of vinyl chloride in samples
collected from these monitoring wells ranged from 16 to 21
micrograms per Liter (yug/L) . An elliptically shaped vinyl
chloride plume of approximately 1,000 feet in length and 400 feet
in width along the southern and southwestern (downgradient)
landfill boundary was identified during the RI. The vinyl
chloride plume presented in the RI was defir.ad on the basis of
vinyl chloride data from monitoring wells MW-3s, MW-4d, MW-5s,
MW-8, MW-9 and MW-10. Monitoring wells MW-3s and MW-5s were
located a considerable distance from the two monitoring wells
where vinyl chloride was actually detected. For example, MW-3s
and.MW-5s are located approximately 700 feet from the nearest
monitoring well where vinyl chloride was detected. The total
volume of water within this plume was calculated to be
approximately 6.6 million gallons.
Three additional monitoring wells (MW-12, MW-13, and MW-14) were
installed in the vicinity of the vinyl chloride plume during the
PDI to further delineate its limits. Two of these monitoring
wells (MW-12 and MW-13) were located closer to the two RI
monitoring wells where vinyl chloride was detected. The
remaining well, MW-14, was also located in closer proximity to
MW-4d and MW-8 but was also placed between MW-9 and MW-10 to
determine whether the vinyl chloride plume extended further
towards the southwest. The data developed during and since the
PDI demonstrate that vinyl chloride was not detected at
cone .tra .ons e.. ieding the MCL at r.ny of the nev aonitoring
wells installed during the PDI. On the basis of the new
monitoring wells installed in closer proximity to the center of
the plume, the vinyl chloride plume is approximately one-third
smaller than the plume defined.during the RI. The groundwater
sampling conducted during and since the RI show that the vinyl
chloride plume is limited to the landfill wetland area to the
south of the landfill. Additionally, the vinyl chloride
concentrations at MW-4d and MW-8, in the center of the plume,
have decreased over time. 'Using the post-ROD data, the volume of
impacted groundwater within the plume is now estimated at 4.4
million gallons.
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The post-ROD studies indicate that the areal extent of the vinyl
chloride plume is limited and the plume is not expanding.
Additionally, the post-ROD studies have shown that the upper
water-bearing unit pinches out downgradient of the landfill,
thus, inhibiting the downgradient migration of vinyl chloride.
Groundwater in the upper aquifer slowly migrates through the
overlying clay and peat as it discharges to the wetlands and the
Kishwaukee River. In addition, vinyl chloride has not been
detected in surface water samples collected from the Kishwaukee
River or surrounding wetlands. This data suggests that natural
attenuation may be effectively removing vinyl chloride as the
groundwater migrates through the overlying clay and peat
deposits, as described below.
VII. EFFECT OF PDI DATA ON REMEDY SELECTION
At the request of the PRP Group, the U.S. EPA, in consultation
with the IEPA, evaluated whether, in light of the PDI data, the
pump-and-treat component of the remedy was necessary. The PRP
Group also requested that the U.S. EPA evaluate whether, given
the PDI data, a less costly landfill cap could be constructed.
Accordingly, the U.S. EPA compared what had been required in the
original ROD with potential alternative remedial actions.
A. Pump-and-Treat vs Natural Attenuation
Post-ROD Data
The post-ROD database shows the concentrations of vinyl chloride
at monitoring well MW-4d range from 9 to 14 /ug/L and at
monitoring well MW-8 have ranged from 7 to 12 /zg/L. These vinyl
chloride concentrations are approximately one-third lower than
the concentrations observed during the RI (16 to 21 //g/L at MW-4d
and from 20 to 21 /ug/L at MW-8) . This trend of decreasing vinyl
chloride concentrations is significant since it demonstrates that
there appears to no longer be a significant influx of vinyl
chloride from the landfill and that natural attenuation of vinyl
chloride —ny " av occurred even during the relati 'ily .hort
monitoring period since the completion of the RI.
Using the analytical data developed during the RI and the PDI,
and the first order decay formula, the length of time required
for the vinyl chloride concentrations to reach the MCL was
calculated. Assuming that the vinyl chloride concentrations will
continue to decline at this rate, vinyl chloride concentrations
in the center of the plume will reach the MCL of 2 /ug/L in
approximately 20 to 25 years. Therefore, natural attenuation may
lower the vinyl chloride concentrations in groundwater to the MCL
in about 25 years. This 25-year estimate assumes that (1) the
coefficient of first-order decay of vinyl chloride concentrations
Woodstock ROD Amendment
July 1998 15
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will remain constant throughout the duration p£ the groundwater
remediation, and (2) the source of vinyl chloride in the landfill
has been removed.
Natural Attenuation Remedy
The natural attenuation remedy is described in the Preamble to
the NCP as a process that will effectively reduce contaminants in
groundwater to concentrations which are protective of human
health and sensitive ecological environments in a reasonable
timeframe. The natural attenuation remedy is not a no-action
alternative. Rather, contaminant reduction is accomplished by
any or all of the following mechanisms; dilution, adsorption,
dispersion, and biodegradation. The circumstances under which
the natural attenuation remedy should be considered include those
situations where active restoration is not (practicable,
cost-effective, or warranted because of site-specific conditions
and those situations where physical and chemical attenuation
mechanisms will effectively reduce contaminants in groundwater to
concentrations protective of human health in a timeframe that is
comparable to that which could be achieved through active
restoration.
Recent guidance disseminated by the U.S. EPA has clarified'the
circumstances under which a natural attenuation remedy should be
used. These circumstances include the following:
o there is no demand for the resource while the natural
attenuation remedy is in progress;
o long-term exposure controls are in effect to prevent
exposure to contaminated groundwater and ensure
protectiveness;
o the potential for further contaminant migration is low; and
o the natural attenuation remedy is employed in combination
wit" other retried: al measures.
The Site meets each of the criteria stated above. Vinyl chloride
degradation behavior and the degradation rate is dependent upon a
number of environmental factors including the availability of
electron donors (such as natural or anthropogenic organic carbon)
and the concentration of acceptors (such as dissolved oxygen,
nitrate, iron(III) and sulfate) in groundwater. Natural carbon
can be expected to be plentiful in the wetland areas where the
presence of peat is well documented. Vinyl chloride degrades in
a reducing environment, which should be present in a wetland.
The most recent data developed for the Site appears to indicate
that the natural attenuation process has been reducing the
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July 1998 16
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concentrations of contaminants dowr.gradient ojl the landfill. In
addition, the time-frames for implementation of the active pump-
and-treat and the natural attenuation remedies appear to be
similar. Currently, there is ro demand for the groundwater
either on-site, or off-site in the vicinity of the vinyl chloride
plume. Furthermore, institutional controls, current regulations,
and practical land-use considerations will effectively prevent
exposure to groundwater. The hydrogeological and contaminant
distribution data developed demonstrate that the vinyl chloride
plume is stagnant and the maximum concentrations within this
plume appear to be decreasing. Also, the footprint of the vinyl
chloride plume determined during the PDI "is smaller than that
reported during the RI, and the upper water-bearing unit pinches
out downgradient of the landfill. In addition, this ROD
Amendment requires that other remedial measures be employed at
the Site, most significantly, capping of the landfill. Finally,
the natural attenuation remedy does not carry the potential for
deleterious effects to the wetlands that are present with the
active pump-and-treat remedy. Damage to the wetlands under a
groundwater pump-and-treat scenario include physical damage
resulting from system construction and the potential dewatering
of wetland areas during long-term system operation.
On the basis of the above evaluation, it is clear that this Site'
meets each of the U.S. EPA's criteria for implementation of a
natural attenuation remedy.
Pump-and-Treat System
The active groundwater pump-and-treat system required by the
original ROD would have reduced the vinyl chloride concentrations
in. the plume to the MCL within approximately 16 to 22 years.
This estimate is based upon the following assumptions:
o there is approximately 4.4 million gallons of contaminated
groundwater present in the vinyl chloride plume;
o a sustained numping rate of bet-ween 4 and 5 ^aliens per
minuce will oe .achieved during the remediation; and
o ten aquifer pore volumes will need to be flushed from the
plume area to achieve the MCL for vinyl chloride.
Summary
Evaluation of the above information demonstrates that there does
not appear to be a significant difference in the length of time
required to effect cleanup between the active pump-and-treat
remedy and the natural attenuation remedy. The vinyl chloride
plume is located entirely within the wetland area downgradient of
the Site. The vinyl chloride present within this plume appears
Woodstock ROD Amendment
July 1998 17
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to be undergoing natural attenuation. Given .the additional
concerns regarding the potential deleterious effects to the
wetlands which may result during implementation of the pump-and-
treat remedy (which were mentioned :.n the original ROD) , this
remedial technology may not be warranted and a natural
attenuation remedy may be more environmentally appropriate.
Post-ROD Amendment Sampling Program
The U.S. EPA is not yet prepared, however, to eliminate the pump-
and-treat component of the original remedy entirely. Although
the post-ROD vinyl chloride concentrations in MW-4d and MW-8 are
lower than those observed during the RI, the post-ROD data may
also show a trend of increasing vinyl chloride concentrations in
both wells. The vinyl chloride concentration in MW-4d rose from
9 micrograms per liter (ug/L) in October 1995 and March 1996, to
14 ug/L in April 1997. Similarly, the concentration in MW-8
increased from 7 ug/L in June 1996, to 12 ag/T' in September 1996
and April 1997. In light of the reduction ±n vinyl chloride
concentrations between the RI and the post-ROD period, the recent
trend of increasing vinyl chloride concentrations may indicate
the presence of a source of.vinyl chloride whose strength varies
over time. The decrease in vinyl chloride concentrations between
the RI and the post-ROD period may be the result of the varying
strength of the vinyl chloride source rather than natural
attenuation, or changes in water chemistry that interrupted the
natural attenuation process. Therefore, the actual timeframe for
remediation of the vinyl chloride plume via natural attenuation
cannot be estimated with reasonable accuracy until additional
information is developed from a post-ROD Amendment sampling
program.
B. Landfill Cap Modifications
The original ROD for the Site required construction of a .landfill
cap that included the following parameters:
o plr -sment of a geosynthetic liner with a bentonite clay
layer, with a 1 x 10-7 cm/s permeability;
o three feet of final cover layer;
o placement of a drainage layer, rooting zone layer and
topsoil;
o installation of a surface water control system.
As noted above, the PDI data indicated that the rate of surface
water infiltration appears to be less than the rate determined
during the RI. As a result, the landfill may be generating less
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July 1998 18
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leachate than the U.S. EPA believed at the tijne of the original
ROD.
The U.S. EPA also evaluated the PDI data in light of recent
guidance generated by Region 5's Working Group Reviewing Landfill
Cover Requirements. (See April 14, 1998, Region 5 Guidance,
contained in the Administrative Record for the Site.) The Region
5 Workgroup concluded, among other things, that frost protection
and drainage layers were two critical landfill cap components,
and that often these components can make for a more effective
remedy at a competitive cost. The Workgroup concluded that
drainage layers are particularly important at Sites where a
leachate collection or a. groundwater containment system has not
been required.
1
In light of the new data and increased technical expertise on
landfill cap designs, the U.S. EPA, in consultation with the
IEPA, reviewed the landfill cap components or the original ROD.
The U.S. EPA sought to determine whether an alternative landfill
cap could be constructed that remained compliant with 35 IAC 811,
the ARAR for the landfill cap, did not need to include a frost -
protective layer, but did include a drainage layer as a
consideration in lieu of not having a leachate collection system.
The U.S. EPA, in consultation with the IEPA, concluded that 35
IAC 811 would be satisfied, and frost protection of the low
permeability layer would not be necessary, if a geomembrane was
used and the landfill cap included the following components:
o recompacting the top 12 inches of the existing cover to
achieve a 95 percent compaction by Standard Proctor Density
(SPD) tests, in order to provide a firm soil foundation
suitable for installing the landfill cover (if 95 percent
compaction is not achievable, compaction will be to the
highest achievable percentage, but not less than the
compaction achievable by a minimum of three (3) passes over
the regraded area with a vibratory compactor of at least 10-
tons total weight);
o installation of a 40-mil linear low density polyethylene
liner;
o installation of a drainage layer;
o installation of a geofabric to protect the integrity of the
drainage layer;
o Installation of 24 inches of soil cover above the drainage
layer, 6 inches of which must be topsoil;
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July 1998 19
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o final grading of the total cover to no less than 2.0% slope.
Summary
The June 30, 1993, ROD required the design and implementation of
a groundwater pump-and-treat system to remediate the vinyl
chloride plume. It appears from the PDI and IMP that this
remedial component may not be needed, since groundwater
remediation may be effectively =)ccoTiplished through natural
attenuation. Groundwater migration through natural clays and
organic peat material appears to be providing natural attenuation
of residual contamination prior to discharge to the Kishwaukee
River.
Therefore, through this ROD Amendment, the U.S. EPA (in
consultation with.the IEPA) is making the implementation of a
groundwater pump-and-treat remedy a contingent part of the final
remedial action for the Site. After installation of the landfill
cap, ground water and surface water quality will be evaluated
through the performance of regular monitoring events, which will
be detailed in the final RD/RA Work Plan. If the data from the
monitoring program demonstrates that natural attenuation is
remediating the vinyl chloride in the groundwater plume to a
degree and at a rate acceptable to the U.S. EPA (in consultation
with the IEPA), then the design, construction, and implementation
of the groundwater pump-and-treat will not be required as part of
the Site's final remedy. If, however, the U.S. EPA, in
consultation with the IEPA, determines that the monitoring data
indicates that natural attenuation is not occurring to an
acceptable degree or at an acceptable rate, then the pump-and-
treat system required in the original ROD will remain a part of
the final remedial action for the Site.
The U.S. EPA will evaluate the effectiveness of natural
attenuation as part of the 5-year review process required for
sites where wastes are left on site. If the data available at
the first such review is insufficient for a reliable trend
ana" '3is, evaluation of remedy perfcrrance will be completed in
the sub_^quent review or at some earlier time to be established
during the initial 5-year review.
Finally, the landfill cap specified in this ROD Amendment will
significantly reduce leachate generation, which should further
improve the groundwater quality. Furthermore, the cap will
comply with the landfill cap ARAR, and will generally not be
subject to damage from freeze/thaw or wet/dry cycles. The
landfill cap specified in this ROD Amendment also requires an
efficient drainage layer that will virtually eliminate standing
water from the protective layer, thus eliminating infiltration
through the barrier layer, thereby increasing the operational
Woodstock ROD Amendment
July 1998 20
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effectiveness of the landfill cap in limiting, surface water
infiltration.
These modifications to the oricinal ROD, based primarily upon the
PDI data and increased technical expertise with landfills, will
result in a reduction in the cost of the remedy of approximately
$2.5 million.
VIII. SUMMARY OF SITE RISKS
Risks to Human Health
The assessment of impacts to human health is called the Baseline
Risk Assessment (BLRA). Using information about what
contaminants are present at the Site, as well as the
concentrations, quantities, locations and'ability of the
contaminants to migrate, a BLRA was developed to determir.3 what,
if any, human health risks are posed by the 5l!:e.
Separate calculations were made for those compounds that can
cause cancer and for those that can have other health effects.
For the compounds that can cause cancer (carcinogens), risks were
estimated as the additional possibility of developing cancer due
to exposure to the compounds. For the non-cancer causing
compounds (noncarcinogens), a risk number called the hazard index
(HI) was calculated so that, if the risk is less than or equal to
1, no adverse health effects would be expected. If the risk is
greater than 1, adverse health effects are possible.
The BLRA indicated that the Site, as it now exists, may pose an
unacceptable cancer risk (CR) of 5 x 10~5 or CR = 5 x 10 ) to
trespassers (children/adolescents playing on-Site) through
exposure to surface soils. This exposure may occur through
ingestion or dermal contact with polynuclear aromatic
hydrocarbons (PAHs) which are present in the contaminated surface
soil. An additional physical hazard is currently posed to
children by the debris piles and miscellaneous debris located on
the Site
The BLRA also identified unacceptable cancer and non-cancer risks
posed by the Site under future land-use scenarios. As mentioned
above, under the current land use conditions, exposure to PAHs in
the surface soil poses an unacceptable level of cancer risk to
trespassers. In addition, under the potential future use
scenario of the Site being used as a park or recycling center,
consumption of leachate from an on-Site well was estimated to
pose a potential non-cancer (hazard index of 10 or HI = 10) and
cancer (CR = 4 x 10"") risk to these park users. The primary
chemicals that posed a non-cancer risk due to leachate
consumption were cadmium, cobalt, copper, lead, nickel and zinc.
The primary chemicals that posed a cancer risk were arsenic and
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beryllium. Another potential health risk wou.Id" also exist if a
well was placed in or near the area contaminated with vinyl
chloride. In this scenario, an unacceptable cancer risk (CR = 1
x 10~3) exists if groundwater con .aminated with vinyl chloride
was consumed over a long exposure period by the resident(s)
drinking from a contaminated well.
Environmental Risks
The ecological assessment conducted for the Site has determined
that copper, mercury, and zinc concentrations in the surface
soils at the Site may adversely affect small terrestrial mammal
populations. Exposure of aquatic species to iron which was
detected in exceedance of regulatory criteria also poses a
potential risk. No conclusions.could be reached as to whether
past ecological effects have occurred due tp the presence of
other inorganic contaminants in surface water and sediments at
the Site due to the lack of biota sampling cr biological assays.
It is important to understand that the U.S. EPA has been directed
by Congress to restore groundwater to its beneficial uses,
whenever practicable.1 The aquifers underlying the Site have
been designated by the State of Illinois as Class I, i.e. a
potential drinking water source. Federal MCLs, or more stringent
state groundwater standards, are therefore ARARs for the
groundwater at the Site. An exceedence of a federal MCL
signifies that groundwater is unacceptably contaminated. Because
of the threat to an important natural resource, an exceedence of
an MCL, alone, can justify remedial action at a Site.2
Overall Protection of Human Health and Environment
The BLRA indicated that there is no current exposure to
groundwater contamination present in the upper water-bearing unit
downgradient of the landfill. However, the BLRA concluded that
there is the potential for future excess risk to human health as
a result of the presence of vinyl chloride. The considerable
post-ROD database developed during the PDI and the IMP indicates
1 NCP, Part 300 .430(a) (ii) (F) - EPA expects to return usable
ground waters to their beneficial uses wherever practicable,
within a timeframe that is reasonable given the particular
circumstances of the site. When restoration of ground water to
beneficial uses is not practicable, EPA expects to prevent
further migration of the plume, prevent exposure to the
contaminated ground water,' and evaluate further risk reduction.
. 2 Role of the Baseline Risk Assessment in Superfund Remedy
Selection Decisions, OSWER Directive 9355.0-30, April 22, 1991.
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July 1998 22
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that the area of vinyl chloride contamination."in the upper
water-bearing unit is limited. Moreover, the areal extent of the
upper water-bearing unit downgraaient of the Site is limited.
The vinyl chloride plume is located entirely within a wetland
area, which is likely to remain open space for the foreseeable
future. The vinyl chloride plume is not migrating any further in
a downgradient direction.
The ROD Amendment remedy will L>fe protective of human health and
the environment. The risks associated with a hypothetical future
exposure of a resident using drinking water on the landfill or
within the wetland area are not likely to occur since the PDI
confirmed that contaminants lie completely within the
landfill/wetland area where residential use is prohibited.
Establishment of a groundwater managementt zone (GMZ) consistent
with Illinois regulations (35 IAC Section 620) and existing
restrictions on issuance of a well construction permit under the
current Illinois Water Well Regulations (77 IAC Section 920) will
effectively restrict the use of groundwater downgradient of the
Site, thus, ensuring protection of human health while natural
attenuation is occurring.
Summary
Actual and threatened releases of hazardous substances are
occurring at and from this Site. The source of the risks
originate from the contaminants within and emanating from the
landfill through releases to groundwater, surface water,
sediments, soils, and air. If not addressed, these releases may
.present an imminent and substantial endangerment to public
health, welfare or the environment. Thus, it is necessary that
corrective and mitigative action be taken to address the threats
posed by the actual or threatened releases.
IX. DESCRIPTION OF ALTERNATIVES
Based on the results of the RI, PDI, quarterly monitoring, the
Petition for an ^SD, and the Petition for a ROD amendment, a list
of ^_Lter..dtives was assembled to address the Site remedial action
objectives and ensure compliance with the requirements of the
NCP. These alternatives were presented in detail in the
Feasibility Study prepared for this Site. Alternatives 1 and 7
(below) have been selected from the original FS and are briefly
described below. Alternative 12 was first presented in the
Proposed Plan for this ROD Amendment. All alternatives have been
updated to reflect 1998 dollars and costs.
ALTERNATIVE 1 (FROM JUNE 30, 1993, ROD) - NO ACTION
CERCLA requires that the No Action alternative be evaluated at
every site to establish a baseline against which all other
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alternatives are compared. Under this alternative, no remedial
actions would take place and the Site would remain in its present
condition .
Capital cost: 0
Maintenance and monitoring cost: $10,000
Estimated present net worth: $22,000
Estimated time to implement: None
Note: The $10,000 maintenance and monitoring cost is not an
annual cost, but reflects the cost of reviewing Site conditions
on a five year basis.
ALTERNATIVE 7 - INSTITUTIONAL CONTROLS, CONSTRUCT GEOSYNTHETIC
CLAY CAP, GROUNDWATER EXTRACTION SYSTEM, AND MONITORING (ORIGINAL
REMEDY SELECTED IN THE JUNE 30, 1993, ROD)
The purpose of Alternative 7 is to minimize infiltration, promote
surface water runoff, eliminate leachate seeps, isolate the
contaminants of concern, and remediate the contaminated
groundwater. These major elements of Alternative 7 include:
o Institutional controls
o Monitoring
o Geosynthetic clay cap
o Groundwater extraction, treatment, and discharge
Institutional controls would include land use restrictions and
deed restrictions to preclude groundwater usage. The primary
objectives of monitoring would be to monitor sedimentation basin
and wetlands water quality, groundwater quality, and the
condition of the landfill cap. Periodic groundwater sampling and
analysis would be performed. Regular visual inspections would be
conducted to evaluate the integrity of the landfill cap, and to
check for erosion and differential settlement.
The lan^-xl cap would be constructed as specified in J5 IAC
811.314. Generally, this includes removing the existing trees
and brush, regrading the surface, sealing the leachate seeps,
placement of a geosynthetic liner with a bentonite component,
placement of a drainage layer, a rooting zone layer, and topsoil .
The cap would then be revegetated. The geosynthetic clay layer
would have a permeability comparable to 3 ft. of compacted clay
(1 x 10"7 cm/s) . The geosynthetic clay cap would extend to the
edge of the landfill and would avoid the adjacent wetlands. The
trees and brush removed from the landfill would be appropriately
disposed of. Erosion control measures would be taken to protect
the perimeter wetlands. A surface water control system would be
designed appropriate to the final grade such that it would limit
Woodstock ROD Amendment
July 1998 24
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erosion of the landfill cover from sheet flow'* would not cause
degradation of adjacent wetlands, meet local stormwater retention
requirements, and allow for the monitoring of surface water
runoff at distinct discharge po.nts.
The groundwater extraction system would consist of installing
groundwater extraction wells in the area of vinyl chloride
contamination. Groundwater would then be pumped from the
extraction system to the POTW. Cn-Site treatment would be
required only if pretreatment standards were exceeded during this
action.
Capital cost: $7,054,000
Annual maintenance and monitoring cost: $129,000
Estimated present net worth: $8,655,000
Estimated time to implement: ' f months
ALTERNATIVE 12 - INSTITUTIONAL CONTROLS, CONSTRUCT MODIFIED
(GEOSYNTHETIC) CAP, MONITORING, AND NATURAL ATTENUATION
GROUNDWATER REMEDY, WITH CONDITIONAL ACTIVE PUMP-AND-TREAT SYSTEM
The purpose of Alternative 12 is to minimize infiltration,
promote surface water runoff, eliminate leachate seeps, isolate
the contaminants of concern, and remediate the contaminated
groundwater. The following remedial actions from the June 30,
1993, ROD will not be modified by this ROD Amendment, and are
included as part of this Alternative: fencing; contaminated
soil/sediment excavation and consolidation; landfill gas
collection system; well monitoring and remedy monitoring
programs; institutional controls; correction of work
deficiencies; and wetland mitigation. The major elements of
Alternative 12 include:
o Institutional Controls
o Monitoring
o Modified Geosynthetic Cap
o Natv.al Attenuation Groundwater Remedy, with conditional
requirement for installation of the active pump-and-treat
system required by the June 30, 1993, ROD in the event that
natural attenuation was not successful in remediating
groundwater
Institutional controls would include land use restrictions and
deed restrictions to preclude groundwater usage.
The primary objectives of monitoring would be to monitor
sedimentation basin and wetlands water quality, groundwater
quality, and the condition of the landfill cap. Groundwater
sampling and analysis would likely be done on a periodic basis.
Woodstock ROD Amendment
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Periodic visual inspection of the landfill cap"and monitoring for
differential settlement would also be performed.
Landfill Cap: As modified, the landfill cap parameters would
comprise:
o Recontouring and regrading of existing cover;
o recompacting the top 12 inches of the existing cover to
achieve a. 95 percent compaction by Standard Proctor Density
(SPD) tests, in order to provide a firm soil foundation
suitable for installing the landfill cover (if 95 percent
compaction is not achievable, compaction will be to the
highest achievable percentage, but not less than the
compaction achievable by a minimum of .three (3) pass.es over
the regradcv- area with a vibratory compactor of at least 10-
tons total weight);
o Installation of a 40-mil linear low density polyethylene
liner;
o Installation of a drainage layer of either 12 inches of
sand/gravel or a geonet;
o Installation of a geofabric between the drainage layer and
the soil cover above;
o Installation of 24 inches of soil cover above the drainage
layer, of which 6 inches must be topsoil (if 12 inches of
sand or gravel is used for a drainage layer, the total cover
above the low permeability layer would be 36 inches); and
o Final grading of the total cover to no less than 2.0 percent
.slope, after accounting for anticipated settlement.
The TT S. EPA estimates the cost of a landfill cap constructed in
acc^idance with these parameters to.be approximately $4.5
million.
Natural Attenuation with Contingent Pump-and-Treat System: Long-
term monitoring of groundwater- would be conducted to monitor and
ensure the effectiveness of natural attenuation. Monitoring
results will be evaluated annually to aid in predicting
contaminant trends. A monitoring program would be developed
during the remedial design-phase and would include the
development of a continuous monitoring record; identification of
select locations to monitor changes in both the horizontal and
vertical extent of contamination; sampling frequency; and
Woodstock ROD Amendment
July 1998 26
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identification and monitoring of areas containing higher
contaminant concentrations. The approximate cost of the long-
term monitoring is estimated at $10,000 per year.
The U.S. EPA would evaluate the effectiveness of natural
attenuation as part of the 5-year review process required for
sites where wastes are left on site. If the data available at
the first such review is insufficient for a reliable trend
analysis, evaluation of remedy performance will be completed in
the subsequent review or at some earlier time to be established
during the initial 5-year review.
In the event that the trend analyses indicated that natural.
attenuation was not remediating the groundwater at a rate and to
a degree acceptable to the U.S. EPA, in cqnsultation with the
IEPA, then the active pump-and-treat system required by the June
30, 1993 ROD would be a required part of this Alternative.
Capital cost: $4,500,000
Annual maintenance and monitoring cost: $129,000
Estimated present net worth: $6,101,000
Estimated time to implement: 6 months
X. COMPARATIVE EVALUATION OF ALTERNATIVES
The NCP requires that the alternatives be evaluated against nine
evaluation criteria. This section summarizes the relative
performance of the alternatives by highlighting the key
differences among the alternatives in relation to these criteria.
The nine evaluation criteria are categorized as: (1) Threshold
Criteria; (2) Primary Balancing Criteria; and (3) Modifying
Criteria. Each of these terms is described as follows:
THRESHOLD CRITERIA
1) Overall protection of human health and the environment
addresse wheth~v a remedy provides adequate pro* ction of hurr n
health and the environment and describes how risKS posed through
each exposure pathway are eliminated, reduced or controlled
through treatment and engineering controls. The selected remedy
must meet this criteria.
2) Compliance with ARARs addresses whether a remedy will meet
federal and state environmental laws or justifies a waiver from
such requirements. The selected remedy must meet this criteria
or waiver of the ARAR must be obtained.
PRIMARY BALANCING CRITERIA
Woodstock ROD Amendment
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3) Long-term effectiveness and permanence refers to expected
residual risk and the ability of a remedy to maintain reliable
protection of human health and the environment over time, once
cleanup goals have been met.
4) Reduction of toxicity, mobility, and volume through treatment
is the anticipated performance of the treatment technologies a
remedy may employ.
5) Short-term effectiveness signifies: (1) short-term risks to a
community during implementation of an alternative; (2) potential
affects on workers engaged in implementation of the remedy; (3)
potential environmental effects of the remedial action and
effectiveness of mitigative measures; and (4) time until
protection is achieved. '
6) Implementability is the technical and administrative
feasibility of a remedy, including the availability of materials
and services needed to implement a particular option.
7) Cost includes estimated capital and O&M costs, also expressed
as net present-worth cost.
MODIFYING CRITERIA
8) Support Agency (IEPA) acceptance reflects aspects of the
preferred alternative and other .alternatives the IEPA favors or
objects to, and any specific comments regarding federal and state
ARARs or the proposed use of waivers.
9) Community acceptance summarizes the public's general response
to the alternatives described in the proposed plan and in the
RI/FS, based on public comments received.
Overall Protection of Human Health and the Environment: The U.S.
EPA, in Consul ation -ith the IEPA, lv s concluded that
Alternative 1 would not satisfy the criterion of ensuring the
overall protection of human health and the environment. The
baseline risk assessment has documented unacceptable risks
present at the Site and groundwater contaminant concentration
levels exceed the federal MCLs. Alternative 1 does not meet the
criterion because no remedial action would be taken and
consequently, the present and future risks posed by the Site
would not be adequately addressed, and further leachate
generation and releases of contaminants to the environment would
not be prevented.
Woodstock ROD Amendrent
July 1998 28
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Alternatives 7 and 12 would be protective of ..human health and the
environment with regard to exposure to surface soils. The
differences in cap design between these two alternatives is a
function of their complexity: e-ach would result in increased
protectiveness from surface soil exposure. The surface water
seeps which are a result of leachate generation are expected to
be eliminated through placement of a cap on the landfill. The
caps proposed may have the undesirable effect of trapping gas
inside the landfill, resulting in a potential increase in lateral
migration of landfill gas. This will be remedied through
placement of a venting system in the landfill.
The Baseline Risk Assessment indicated that there is no current
exposure to the groundwater contamination present in the upper
water-bearing unit downgradient of the landfill. However, the
Baseline Risk As^assment concluded that there is the potential
for future excess risk to human health as a result of the
presence of vinyl chloride. The considerable post-ROD database
developed during the PDI and the IMP indicates that the area of
vinyl chloride contamination in the upper water-bearing unit is
limited. Moreover, the areal extent of the upper water-bearing
unit downgradient of the Site is limited. The vinyl chloride
plume is located entirely within a wetland area, which is likely
to remain open space for the foreseeable future. The vinyl
chloride plume is not migrating any further in a downgradient
direction.
Both the June 30, 1993, ROD remedy and Alternative 12 would be
protective of human health and the environment. The risks
associated with a hypothetical future exposure of a resident
using drinking water on the landfill or within the wetland area
are not likely to occur since the PDI confirmed that contaminants
lie completely within the landfill/wetland area where residential
use is prohibited. Establishment of a GMZ consistent with
Illinois regulations (35 IAC Section 620) and existing
restrictions on issuance of a well construction permit under the
current Illinois Water Well Regulations (77 IAC Section 920) will
efft__cively restrict the use of groundwater downgradient of the
Site, thus ensuring protection of human health while natural
attenuation is occurring.
Compliance With ARARs: A listing of all ARARs associated with
each alternative can be found in Table 11 of the FS. The ARARs
for the new Alternative 12 are the same as the ones for
Alternative 7. The U.S. EPA concurred with the lEPA's
recommendation that, although the Site was closed pursuant to 35
IAC 807, certain requirements of 35 IAC 811 are relevant and
appropriate to the landfill cap component of the remedy. More
particularly, the U.S. EPA has determined that the following
requirements of 35 IAC 811.314 are relevant and appropriate to
Woodstock ROD Amendment
July 1998 29
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the landfill cap to be constructed as part of. t"he final remedy
for the Site: (1) alternative specifications for the low
permeability layer provided that performance is equal to or
superior to the performance of a layer meeting the requirements
of subsections (b)(3)(A)(i) and (b)(3)(A)(ii) [35 IAC
811.314(b) (3) (A) (iii) & 35 IAC 811.314(b) (3) (C)] ; and (2)
preparation and compaction requirement [35 IAC
811.314(b) (3) (B) (iii)] .
Only Alternatives 7 and 12 would comply with all chemical,
action, and location specific ARARs associated with the Site.
Other remedial alternatives exist which would not require
mitigating the loss of these wetlands. (As a general matter,
when the U.S. EPA selects a remedy that results in a loss of
wetlands, mitigating the loss of those wetlands requires
replacement on a 2 to 1 ratio.)
Thf= U.S. EPA, in consultation with the IEPA, has determined that
Alternative 12 would also comply with ARARs, including relevant
and appropriate landfill cap requirements of 35 IAC 811, and
would eliminate the Agency's concern about adverse impacts to the
wetlands due to the construction and operation of a groundwater
pump-and-treat system. Implementation of a natural attenuation
remedy would require the establishment of a GMZ consistent with
Illinois regulations (35 IAC Section 620).
Long-term Effectiveness and Permanence: Capping the landfill
would contain the surface soils, sediments, sludges and wastes
effectively. A cap would permanently reduce infiltration into
the landfill, thereby reducing leachate generation to the maximum
extent practicable. Both capping alternatives would eliminate
human exposure to the contaminated surface soils and would also
minimize-the ecological risks posed by this media, with
Alternative 11 being most protective due to the thickness of the
cap. Alternatives 7 and 12 both provide for a drainage layer,
which should contribute to long-term effectiveness of the remedy
by ensurina that <-he cap is not damaged by standina water.
Alternative 7, which requires groundwater extraction, would be
effective in preventing further migration of the vinyl chloride
and would ultimately eliminate the thr.-eat posed by this media
through extraction and treatment. Alternative 12, which requires
natural attenuation of contaminated groundwater, would also be
effective in preventing further migration of the vinyl chloride,
would ultimately eliminate the threat posed by this media, and
would eliminate the concern with potential adverse impacts to the
wetlands due to the construction and operation of a groundwater
pump-and-treat system.
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July 1998 30
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Reduction of Toxicity, Mobility or Volume: None of the
alternatives would reduce the toxicity or volume of the in-situ
landfill wastes. Alternative 1 wo'jld only require monitoring and
institutional controls. Alternatives 7 and 12 are containment
alternatives. Both capping alternatives would reduce the volume
of leachate being produced by minimizing infiltration. Each
capping alternative would also reduce the mobility of the
contaminants.
Using the maximum concentration noted in the plume during the PDI
(14 ^g/L) and an estimated volume of 4.4 million gallons of
groundwater, there appears to be less than 0.5 pounds of vinyl
chloride present in the plume. The vinyl chloride plume is not
expanding any further in a downgradient direction, and the
post-ROD data indicate the plume is smaller than defined during
the RI. Alternative 7 (June 30, 1993, ROD remedy) would reduce
the toxicity, mobility and volume of contaminants in the
groundwater through an active groundwater extraction system.
Alternative 12 would reduce the toxicity, mobility and volume of
vinyl chloride contamination in the groundwater through natural
attenuation. Each of these remedies would be equally effective
in reducing the volume of vinyl chloride.
Short-term Effectiveness:
(1) Short-term community risks: Remediation activities under any
but the no-action alternative would result in some risk of injury
to community residents, due primarily to increased truck traffic
on other related construction activities. Construction
activities would also result in dust generation. The U.S. EPA
believes, however, that traffic and dust control measures could
be implemented so that any risk posed to the community could be
minimized.
(2) Worker protection: During implementation of any but the no-
action alterative, workers may be exposed to contaminated soils
and other wastes. The U.S. EPA believes, however, that well-
establisu^d p_c rtiva measures would sufficient" • encore woiker
safety during implementation of any of the alternatives.
(3) Environmental effects and mitigative actions: Natural
attenuation of the vinyl chloride plume under Alternative 12,
would involve no impact to the wetlands. Alternative 7 (the
originally-selected remedy) would involve extraction of the
contaminated groundwater, which could result in dewatering of the
wetlands. This dewatering is a potential short-term effect of
each of these alternatives. (The U.S. EPA believes, however,
that proper design of an extraction system could prevent or
mitigate the threat.)
Woodstock ROD Amenc^nent
July 1998 31
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(4) Time to protection: It is expected that .the duration of
capping activities specified in Alternatives 7 and 12 would not
exceed one year. Active remediation of the contaminated
groundwater, as provided by Alternative 7 is not expected to
exceed 22 years. Natural attenuation of groundwater, as provided
by Alternative 12, would require approximately 25 years.
Implementability: All-the alternatives are readily implementable.
Capping and groundwater extraction have been proven to be an
effective technology in remediating similar threats at other
sites. Constructing a groundwater extraction system would
involve the construction and operation of remedial components
which use standard engineering and construction practices. It is
considered relatively easy to implement, well developed, and
reliable. If treatment is required before discharge, the
technologies for treatment are proven and readily implementable.
The groundwater pump-and-treat remedy is more difficult to
implement due to the construction of a groundwater collection and
treatment system within the wetland area. It is important to
note that the U.S. EPA would not select an alternative that
required construction within a wetland without making a
determination that no practical alternative existed. A U.S.. EPA
policy memorandum on floodplains and wetlands assessment for
CERCLA actions states:
All possible alternatives must be considered, including
the no action alternative. If one or more of the
alternatives will be located in a wetland, those
alternatives may not be selected unless a determination
is made that no practicable alternatives exists outside
the wetlands.3
During the PDI field program, great difficulty was encountered in
accessing the wetland areas for installation of monitoring wells
and soil borinqs. It is expected tha' furthe- J.i f f icvlties would
be encountered during the construction of a groundwater
collection and treatment system in the wetland areas, due to the
spongy nature of the soils. Further, encroachment into the
wetlands during construction of the groundwater pump-and-treat
system would have a deleterious effect on the wetlands
environment. Operation of the system would likely have the same
effect.
U.S. EPA. Office D| Solid \V;iste and Emergency Response Policy on l-'loiulpliims and Wetland Assessments for
CKRCI.A.Actions. August 198").
Woodstock ROD Amendment
July 1998 32
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The natural attenuation remedy in Alternative. 12 would require no
construction and, as such, is quite implementable. In addition,
implementing the natural attenuation remedy would eliminate the
concern with adverse impacts tc the wetlands due to the
construction and operation of a groundwater pump-and-treat
system.
Cost: The costs for the identified alternatives range from
$22,000 (Alternative 1) up to $8,655,000 (Alternative 7) in terms
of present net worth. The capital costs range from $0
(Alternative 1) up to $7,054,000 (Alternative 7). It would cost
approximately $800,000 in capital cost arid long-term O&M costs to
implement the pump-and-treat component of th^ June 30, 1993, ROD.
By contrast, the alternate remedy would require no capital
expenditures and the costs for long-term monitoring are
approximately $10,000 per year.
The following summary table lists each alternative and the
associated costs:
ALTERNATIVE
f 1 . No Action
7. Access Restrictions,
Construct Geosynthetic Clay
Cover, Groundwater
Extraction System, and
Monitoring
12. Access Restrictions,
Modified Landfill Cover,
Natural Attenuation,
Contingent Pump-and-Treat ,
and Monitoring
COSTS
Capital O&M PNW
$0
$7,054,000
$4,500,000
$10, 000
$129,000
$129,000
$22, 000
$8,655,000
$6, 101, 000
Support Agency Acceptance: The IEPA has assisted in the development
and review of materials in the Administrative Record. The IEPA has
concurred with the originally selected remedy, as well as Alternative
12.
Community Acceptance: The residents of Woodstock, Illinois have been
active participants in the remedy selection process at this Site. The
affected community has expressed its desire for a protective remedy,
but one that takes costs into account. The U.S. EPA has been
sensitive to the fact that the municipality of Woodstock is a
potentially responsible party for the Site. The concerns of .the
presidents of Woodstock, as well as the Agency's responses thereto, are
Woodstock ROD Amendment
July 1998
33
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set forth in the Responsiveness Summaries of this Amendment and the
original ROD.
XI. DESCRIPTION OF SELECTED REMEDY
Based on its complete evaluation of the PDI data, the alternatives
discussed above, and recent U.S. EPA guidance on landfill caps, the
U.S. EPA, in consultation with the IEPA, has selected Alternative 12
as the Amendment to the original Site remedy. Alternative 12,
together with those components of the original remedy that remain
unchanged (fencing; contaminated soil/sediment excavation and
consolidation; landfill gas collection system; well monitoring and
remedy monitoring programs; institutional controls; correction of work
deficiencies; and wetland mitigation), will be protective of human
health and the environment, comply with ARARs, b,e cost-effective, and
will utilize permanent solutions to the maximum extent practicable.
The majcr elements of this alternative include revising the landfill
cap component and the groundwater pump-and-treat requirement of the
remedy selected in the June 30, 1993 ROD.
Landfill Cap: As modified, the landfill cap parameters comprise:
o Recontouring and regrading of existing cover;
o recoirpacting the top 12 inches of the existing cover to achieve a
95 percent compaction by Standard Proctor Density (SPD) tests, in
order to provide a firm soil foundation suitable for installing
the landfill cover (if 95 percent compaction is not achievable,
compaction will be to the highest achievable percentage, but not
less than the compaction achievable by a minimum of three (3)
passes over the regraded area with a vibratory compactor of at
least 10-tons total weight); «
o Installation of a 40-mil linear low density polyethylene liner;
o Ins lia.__Lon of a drainage layer of ei^ner 12 inches o:"
sand/gravel or a geonet;
o Installation of a geofabric between the drainage layer and the
soil cover above;
o Installation of 24 inches of soil cover above the drainage layer,
of which 6 inches must be topsoil (if 12 inches of sand or gravel
is used for a drainage layer, the total cover above the low
permeability layer would be 36 inches); and
Woodstock ROD Amendment
July 1998 34
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o Final grading of the total cover to no less tjian 2.0 percent
slope, after accounting for anticipated settlement.
The U.S. EPA estimates the cost of a landfill cap constructed in
accordance with these parameters to be approximately $4.5 million, a
significant savings over the estimated cost of the landfill cap
required by the original ROD (~$6.2-million). Most importantly, after
careful consideration, the U.S. EPA and the IEPA jointly believe that
such a cap will be as protective of human health and the environment
as the cap required by the original ROD.
Groundwater Pump-and-treat: The other component of the June 30, 1993,
ROD remedy that the U.S. EPA is modifying is the requirement to
construct a groundwater pump-and-treat system to address residual
vinyl chloride contamination in the upper water-bearing unit,
downgradient of the landfill. This ROD Amendment makes the pump-and-
treat system a contingent component of the landfill remedy, required
only if natural attenuation of the vinyl chloride plume does not occur
at a rate and to the degree acceptable under state and federal law.
•The U.S. EPA will evaluate the effectiveness of natural attenuation as
part of the 5-year review process required for sites where wastes are
^Left on site. If the data available at the first such review is
•.nsuf ficient for a reliable trend analysis, evaluation of remedy
performance will be completed in the subsequent review or at some
earlier time to be established during the initial 5-year review. If
natural attenuation sufficiently remediates the contaminated
groundwater, the remedy for the Site will cost approximately $800,000
less than calculated in the original ROD.
Groundwater cleanup standards must be achieved within a reasonable
period of time for the contaminants of concern. The determination of
whe.ther additional measures will be required for groundwater will be
based on compliance with the cleanup levels within a reasonable period
of time. For this type of situation, a reasonable period of time for
meeting the MCLs can be defined as less than 30 years.
Long-term Mon^^oring: .uong-term monitoring of groundwacer will be
conducted to monitor and ensure the effectiveness of the remedy.
Monitoring results will be evaluated annually to aid in predicting
contaminant trends. The monitoring program will be developed during
the design phase and will include the development of a continuous
monitoring record; identification of select locations to monitor
changes in both the horizontal and vertical extent of contamination;
sampling frequency; and identification and monitoring of areas
containing higher contaminant concentrations.
5-Year Review: At each 5-year review or earlier, as necessary, the
fc.S. EDA, in consultation with the IEPA, will evaluate the following
Woodstock ROD Amendment
July 1998 35
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criteria in order to determine the need for implementation of the
contingent pump-and-treat remedy:
o Comparison of existing contaminant levels throughout the plume to
MCLs ;
o Trends in contaminant concentrations, if any;
o Effectiveness of the source control measures at cutting-off the
source of contamination at the Site from the down gradient
boundary;
o Potential reduction in restoration time-frames to less than 30
years; ,
o Potential for the contaminants in the ground water to reach
appropriate levels throughout the plume.
Pump-and-treat may be necessary if an evaluation of the above criteria
indicates: (1) concentrations have not decreased; (2) concentrations
do not show the potential to decrease below MCLs in less than 30
years; or (3) source control measures do not meet their remedial
objectives of preventing off-site contaminant migration.
XII. STATUTORY DETERMINATIONS
The selected remedy must satisfy the requirements of Section 121 of
CERCLA to:
1. Protect human health and the environment;
2. Comply with ARARs;
3. Be cost-effective;
4. Utilize permanent solutions and alternate treatment technologies
to the maximum extent practicable; and
5. Satisfy the preference for treatment as a principal element of
the amedy.
The selected remedy for the Site, as modified by this ROD Amendment,
satisfies the requirements of CERCLA as detailed below:
1. Protection of Human Health and the Environment: Implementation of
the selected remedy will reduce and control potential risks to
human health posed by exposure to contaminated ground water,
soil, landfill waste, surface water, and sediments. The selected
remedy will reduce potential exposure to contaminated groundwater
and surface soils to within an acceptable risk range. The
contaminated groundwater will be remediated until the MCL of 2
ppb is reached. The selected remedy also ^rotects the
environment from the potential risks posed by contaminants
Woodstock ROD Amendment
July 1998 36
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discharging to ground water, the Kishwaukee Rjlver, surrounding
soils, sediments, and wetlands.
Institutional controls:
Institutional controls have been implemented to protect against
drinking of contaminated ground water at the Site, and to
prohibit construction which could be detrimental to the remedy.
Capping the landfill:
In addition to reducing the potential risk posed by exposure to
landfill contaminants, capping the landfill will reduce
precipitation infiltration through the landfill, thereby reducing
leachate generation. Ground water contaminant loading, leachate
generation, and seepage into the wetlands will then be reduced or
eliminated. '
Construction of a drainage layer:
The U.S. EPA has determined that construction of a drainage layer
above the barrier layer is necessary to ensure long-term
protection of human health and the environment. Such a drainage
layer will allow water to drain to the perimeter drains of the
landfill cover, minimizing the saturated thickness of standing
water (the head) in the soil over the barrier layer. In the
absence of lateral drainage, water must either go up (evaporate) .
or down (infiltrate). The thickness and persistence of the head
has a direct effect on infiltration through the barrier. Even
synthetic barriers have imperfections from manufacturing and
installation through which water can be transmitted. An
efficient drainage layer with a hydraulic conductivity greater
than 1 X 1CT1 cm/sec, will virtually eliminate standing water in
the protective layer, thus eliminating infiltration through the
barrier layer.
Output results from the HELP model for various landfill cover
profiles with and without drainage layers shows a decrease in
infiltration of two-plus orders of magnitude when a good drainage
layer i added. For r.xample, modelinc, demonstrates th : a final
cover of 36 inches of compacted clay (hydraulic conductivity = 1
X 10"7 cm/sec), with a minimum 36-inch protective/vegetated
layer, even when frost damage is not considered, will allow over
two inches per year of infiltration. A cover with a geomembrane
and a drainage layer with a hydraulic conductivity of 10 cm/sec,
however, will allow less than 0.01 inches of infiltration
annually. This demonstrates that inclusion of a drainage layer
can have a significant effect on generation and migration of
leachate in an unlined landfill.
An effective drainage layer design should maintain the saturated
zone within the drainage layer under a peak storm event and
Woodstock ROD Amendment
July 1996 37
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ensure less than M-inch annual infiltration tjifough the barrier
layer (shown respectively as the peak daily head and average
annual head outputs in the HELP nodel) . A geonet is an excellent
synthetic alternative, and may b<; more cost-effective than
gra\/el, depending on local cost and availability of both
materials.
Most landfill closure ARARs assume that a certain degree of
engineering control already exists (e.g.. bottom liners, leachate
collection systems, etc.). No such engineering controls exist at
the Site. In cases where the ROD requires installation of a
leachate collection and/or ground water containment system, the
importance of a drainage layer would be reduced, except in cases
where it may be needed for slope-stability. However, since this
Site is unlined, has no effective leachate collection system, the
pump-and-treat portion of the June 30, 1991, ROD is being
retained only as a contingent component o.r the remedy, and cne of
thp remedial action objectives is to prevent further generation
of leachate, the addition of the drainage layer to the remedy is
necessary to compensate for the lack of these engineering
controls, and to ensure long-term effectiveness of the overall
remedy.
Gas venting:
A gas venting system will reduce potential risks due to the
landfill gases.
.Excavation and consolidation of contaminated sediments:
The U.S. EPA has required excavation and consolidation of wastes
under the landfill cap to ensure that all wastes are located
completely under the cap and to reduce settlement after capping.
Conclusion: No unacceptable short-term risks will be caused by
implementation of the remedy. However, the nearby community, and
Site workers, may be exposed to noise and dust nuisances during
construction. Standard safety measures should manage any short-
ter^ risks Dust control measures will mitigate risks as well.
Mitxyative measures, as specified during design, will be taken to
prevent and address adverse environmental impacts.
2. Compliance with ARARs: With respect to any hazardous substances,
pollutants or contaminants that will remain on-Site, CERLCA (§
121 (d) (2) (A)) requires the U.S. EPA to select a- remedy which, at
the completion of the remedial action, at least attains such
legally applicable or relevant and appropriate standard,
requirement, criteria, or limitation. The remedy selected in the
original ROD, as modified by this ROD Amendment, will comply with
all federal and state applicable or relevant and appropriate
standards, requirements, criteria or limitations (ARARs). The
Woodstock ROD Amendment
July 1998 38
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remedy will be implemented in compliance with, applicable
provisions of CERCLA and the NCP.
A. Chemical-Specific ARARs: Chemical-specific ARARs regulate
the release to the environment of specific substances having
certain chemical characteristics. Chemical-specific ARARs
typically define the extent.of cleanup at a site.
(1) Soils/Sediments: There are no chemical-specific
standards established for soils and sediments.
(2) Ground Water: As noted above, the aquifers underlying
the Site have been designated as Class I aquifers, i.e.
a potential drinking water source, by the State of
Illinois. The U.S. EPA is aware that a Woodstock
municipal ordinance currently in effect prohibits the
sinking of any groundwater wells at the Site.
Nevertheless, as a Class I aquifer, state and/or
federal drinking water standards are ARARs for this
remedy:
a. Federal ARARs: The Safe Drinking Water Act-'s MCLs
(40 C.F.R. § 141), Maximum Contaminant Level Goals
(MCLGs) that are greater than zero,.and Secondary
Maximum Contaminant Levels (SMCLs) are ARARs for
the Site.
b. State ARARs: The State of Illinois is authorized
to administer the implementation of the federal
Safe Drinking Water Act (SDWA). The State also
has ground water quality standards promulgated
under Title 35, Subtitle F, Chapter I, Part 620.
To the extent that these state ground water
quality standards listed under 620.410 are more
stringent that the federal MCLs, MCLGs greater
than zero, and the SI^CLs, the staf standards are
ARs for the ground water at the ,ite.
In the event that natural attenuation does not
remediate the groundwater at a rate and to an
extent acceptable to the U.S. EPA, in consultation
with the IEPA, and a pump-and-treat system becomes
a part of the remedy for the Site, then 35 IAC
Part 218 will become an ARAR for the remedy.
(3) Surface Water:
a. Federal ARARs:
Woodstock ROD Amendment
July 1998 39
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Section 304 of the Clean Water; Act (CWA)
establishes Ambient Water Quality Criteria (AWQC)
for protection of human health and aquatic life.
The AWCQ are considered relevant and appropriate
at Superfund sites where a release or threat cf a
release is present or when remedial actions
require point source discharges to surface water
bodies. In the event that a pump-and-treat system
is necessary at the Site, the federal AWCQ will be
relevant and appropriate for the discharge.
b. State ARARs: The State of Illinois has been
authorized to implement the National Pollutant
Discharge Elimination System (NPDES) established
under the CWA, as specified-in IAC 35, Part 309.
In the event that natural attenuation does not
remediate the groundwater at a rate and to an
extent acceptable to the U.3. EPA, in consultation
with the IEPA, and a pump-and-treat system becomes
a part of the remedy for the Site, then any
discharge to waters of the State of Illinois, the
chemical specific standards of Title 35, Subtitle
C, Subpart B, Section 302.208 and toxic substances
standards of Section 302.210 of the IAC
establishing General Use Water Quality Standards
will become ARARs for the Site.
B. Location Specific ARARs: Location-specific ARARs are those
requirements that relate to the geographical position of a
site. These include:
(1) Protection of Wetlands:
a.. Federal ARARs: In the event that pump-and-treat is
required, 40 CFR Part 6 is applicable to any
remedial action taken within wetlands. This ARAR
requires that activit.. ;s required in a wetland
must minimize the destruction, loss, or
degradation of the wetland. In addition, any
affected wetlands may be restored, as appropriate.
The substantive requirements of any U.S. Army
Corps of Engineers permit may need to be
fulfilled, due to the potential that activities
during construction may impact the wetlands.
(2) Endangered Species Act: Both the federal Endangered
Species Act (16 U.S.C. § 1531) and the Illinois
Endangered Species Protection Act, Title 17
Woodstock ROD Amendment
July 1998 40
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Conservative Chapter 1, Subchapter .JC, Part 1075
Illinois Administrative Rules, require that actions
must be performed to :onserve the endangered or
threatened species legated .in and around the Site.
Remedial activities should not destroy or adversely
modify the critical habitat upon which endangered
species depend. Prior to conducting remedial
activities, a survey of the Site will be conducted to
determine whether or not endangered or threatened
species may be affected by remedial activities. If such
a threat exists, then the federal and/or state statute
will be relevant and appropriate to the selected
remedy, and therefore an ARAR.
C. Action-Specific ARARs: Action-specif,ic ARARs are
requirements that define acceptable treatment and d? sposal
procedures for hazardous substances.
(1) Federal ARARs:
a. Pretreatment Standards: In the event that a pump-
and-treat system is required, 40 C.F.R. 403 is
applicable to its operation.
b. Surface Water Runoff: 40 CFR 122 is applicable to
any surface water runoff from the Site, including
stormwater runoff.
c. Occupational Safety and Health Act (OSHA)
Requirements: 29 CFR 1910 and 1926 are OSHA
requirements which are applicable to the Site.
Threshold Limit values as established by the
American Council of Governmental Industrial
Hygienists (ACGIH) are relevant and appropriate?
during construction of the remedy.
(2) State ARARs:
a. Closure of Solid Waste Landfills: The selected
remedy will comply with certain substantive
requirements of Title 35, Illinois Solid and
Special Waste Management Regulations, Section 811,
Subpart C for closure of solid wastes landfills,
specifically relating to final cover, air
pollution, and closure requirements. The U.S.
EPA, in consultation with the IEPA, has determined
that these selected standards are relevant and
appropriate to the landfill cap to be constructed
at the Site.
Woodstock ROD Amendment
July 1998 41
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Rationale for Selection of Landfill Cap ARARs: As
reflected in the Responsiveness Summary to the
original ROD and elsewhere in the Administrative
Record, the U.S. EPA's selection of 35 IAC 811 as
the relevant and appropriate standard for the
landfill cap to be constructed at the Site has not
been without controversy..
At the time of the original ROD, the U.S. EPA and
the IEPA were aware that the landfill cap and
closure requirements in effect at the time the
Site was closed (1980) had been superseded by the
more stringent requirements of 35 IAC 810-815,
effective on September 18, 1990. The new Illinois
landfill regulations were pa,ssed,. in large part,
to address landfill cap failures under the old 807
standards. In general, the new Illinois
regulations were more extensxve and more stringent
than the federal RCRA Subtitle D landfill
standards (which were effective October 9, 1991).
The Illinois regulations were revised to
incorporate the aspects of RCRA Subtitle D that
were not already covered by Illinois law, and
allowed Illinois to implement Subtitle D.
The new landfill standards had certain grandfather
provisions. In particular, Part 814, Subpart E of'
the 1990 regulations allowed existing facilities
to close under the old regulations (35 IAC 807) if
closure was initiated by September 18, 1992.
Because the Woodstock landfill (i.e. the Site)
initiated closure earlier than September 18, 1992,
it was entitled under state law to close under the
old 807 closure standards. Federal Superfund law
provides, however, that when hazardous wastes will
be left at a site, state and federal requirements
that may not be directly applicable may still be
relevant and appropriate to the circumstances of
the release. If U.S. EPA makes the determination
that a standard, or a portion of a standard, is
relevant and appropriate, then that standard (or
portion thereof) must be attained by the remedy
just as if the standard were directly applicable.
At the time of the original ROD, both the U.S. EPA
and the IEPA believed that the new 811 landfill
cap standards, even if not directly applicable
under state law to the Site, were relevant and
appropriate to the circumstances of the release.
Woodstock ROD Amendment
July 1998 42
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The IEPA and the U.S. EPA believed (and continue
to believe today) that the public interest would
be ill-served by designating 35 IAC 807 as the
landfill cap standard. The Site was closed under
the requirements of 807, and yet presented a
sufficient hazard to human health and the
environment to be placed on Superfund's list of
national priorities. 35 IAC 807 did not require a
bottom liner, control of gas releases, any
significant long-term maintenance, capping
materials impermeable enough to protect
groundwater, or protection of the cap from
freeze/thaw or wet/dry cycles (which would
ultimately impact cap integrity). Despite
construction in compliance with 807, groundwater
at the Site became contaminated at levels
exceeding federal and state action limits.
The U.S. EPA, in consultation with the IEPA, has
determined that many of the requirements of 35 IAC
811 continue to be relevant and appropriate, and
must be attained by the remedial action at the
Site. The Site will never have a bottom liner or
a leachate collection system, standard components
of all landfills constructed today. The existing
cover is predominantly clay, has been subjected to
repeated wet/dry and freeze/thaw cycles since
installation in 1980, and has failed. Simply
repairing the existing cover under 35 IAC 807 .
would not solve the problem long-term, nor
sufficiently reduce the surface water
infiltration. The existing cover, once re-
contoured and regraded-, would continue to be
subject to formation of macropores from repeated
wet/dry and freeze/thaw cycles.
Rationale for Thickness of Final Cover: As noted
c... jve, in making a relevant and appropriate
determination, the U.S. EPA has a fair degree of
discretion in determining which specific
requirements of a promulgated standard are,
indeed, relevant and appropriate. The Agency has
determined that the three-foot soil cover (over
the barrier layer) requirement is not relevant and
appropriate, and need not be attained by this
remedy.
This remedy will require the installation of a
geomembrane barrier layer. (The Agency has
determined that a geomembrane will minimize the
Woodstock ROD Amendment
July 1998 43
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encroachment of the landfill' s. ''footprint on
adjacent wetlands.) Illinois regulations found at
35 IAC 811.314(b)(3) provide three options for a
low permeability lay;r:
A) A compacted earth layer constructed in
accordance with the following standards:
i) The minimum allowable thickness shall be
0.91 meter (3 feet);
ii) The layer shall be compacted to achieve
a permeability of 1 x 10~7 centimeters
per second and minimize void spaces.
Hi) Alternative specifications may be
utilized provided that the performance
of the low permeability layer is equal
to or superior to the performance of a
layer meeting the requirements of
subsections (b) (3) (A) (i) and
(b) (3) (A) (ii) .
B) A geomembrane constructed in accordance with
the following standards:
i) The geomembrane shall provide
performance equal or superior to the
compacted earth layer described in
subsection (b) (3) (A) .
ii) The geomembrane shall have strength to
withstand the normal stresses imposed by
the waste stabilization process.
Hi) The geomembrane shall be placed over a
prepared base free from sharp objects
and other materials which may cause
damage.
C) Any other low permeability layer construction
techniques or materials, provided that they
Woodstock ROD Amendment
July 1998 44
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provide equivalent or superior performance Co
the requirements of this subsection.
In addition, the Illinois regulations at 35 IAC
811.314(c) also provide standards for the final
protective layer as follows:
1) The final protective layer shall cover the
entire low permeability layer.
2) The thickness of the -final protective layer
shall be sufficient to protect the low
permeability layer from freezing and minimize
root penetration of the low permeability
layer, but shall not be less than 0.^1 meter
(3 feet) . '
3) The final protective layer shall consist of
soil material capable of supporting
vegetation.
4) The final protective layer shall be placed as
soon as possible after placement of the low
permeability layer to prevent desiccation,
cracking, freezing or other damage to the low
permeability layer.
Since geomembrane materials used for the low
permeability layer are not subject to damage from
freeze/thaw or wet/dry cycles, as clay barrier
layers, the U.S. EPA has determined that a final
protective cover of three feet of soil is not
necessary to ensure protectiveness of the cap.
The geomembrane barrier will require only
sufficient cover to protect it from other forms of
damage, such as heavy equipment, root penetration,
or intrusive activities (human or animal). A 24-
inch protective cover, as recommended by the U.S.
EPA guidance, is fully adequate for this landfill.
In addition, the combination of 18 inches of
rooting zone and 6 inches of top soil is more than
adequate to-support vegetative cover.
Slope: The remedy includes, Final grading of the
total cover to no less than 2.0 percent slope,
Woodstock ROD Amendment
July 1998 45
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after accounting for anticipated settlement. The
requirement for establishing a minimum slope after
accounting for the anticipated settlement of the
surface and subgrade of the landfill cover is
intended to provide for rapid removal of water on
the landfill cover and in the drainage layer of
the cover. The U.S. EPA's guidance for
constructing landfill covers recommends a minimum
3 percent slope after accounting for anticipated
settlement. In the case of this Site, the U.S.
EPA has already reduced the minimum slope
requirement from three (3) £r> two (2) percent.
The rationale for doing so in t he case of this
Site is: (1) the average waste thickness is
approximately 7 feet, and isf generally uniform;
(2) the landfill stopped accepting waste in 1975,
and much of the anticipated settlement has already
occurred; and (3) localized Jifferential
settlement is expected to occur, but will be
repaired as necessary during the operation &
maintenance (O&M) phase, once the remedial action
is completed.
b. Groundwater: In the event that the pump-and-treat
system is installed (i.e. natural attenuation is
not successful), any groundwater extracted shall
comply with 35 IAC, Part 307 as well as 35 IAC,
Part 310 which are ARARs for this Site since
pretreatment standards, permitting, and reporting
requirements must be met for POTW discharge.
c. Groundwater Management Zone: 35 IAC, Part 620.250
which provides for the establishment of a
groundwater management zone is an ARAR for the
Site.
Cos*- -Ef f er ' ivene.. Cost effectiveness is determir "1 by
evaluating the following three of the five balancing criteria to
determine overall effectiveness: (1) long-term effectiveness and
permanence; (2) reduction of toxicity, mobility or volume through
treatment; and (3) short-term effectiveness. Overall
effectiveness is then compared to cost to ensure that the remedy
is cost effective.
The selected remedy provides overall cost-effectiveness because
it provides adequate long-term effectiveness and permanence.
Secondary reduction in toxicity, mobility, and volume is
accomplished through natural attenuation of the ground water and
the mitigation of surface water infiltration through the landfill
Woodstock ROD Amendment
July 1998 46
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cap. No unacceptable short-term risks will be caused by
implementation of the remedy.
4. Utilization of Permanent Solutions ind Alternative Treatment
Technologies or Resource Recovery Technologies to the Maximum
Extent Practicable: The selected remedy utilizes permanent
solutions and alternative treatment technologies to the maximum
extent practicable. This finding was made after evaluation of
the protective and ARAR-compliant alternatives for the Site
remedial action and comparison of the trade-offs (advantage
versus disadvantages) among the remedial .alternatives with
respect to the five balancing criteria (see discussion above).
5. Preference for Treatment as a Principal Element: The principal
threats at the Site are the contaminated ground water and
contaminated soil and leachate. The selected remedy uses
treatment as a secondary element of the remedy through the
natural attenuation of contaminated ground water. Due to the
large volume and heterogeneous distribution of waste throughout
the landfill, treatment of the landfill material itself is not
practicable at this Site.
SUMMARY
The remedy selected in the ROD of June 30, 1993, as modified by
this ROD Amendment, is protective of human health and the
environment, complies with federal and state ARARs and is cost-
effective. The selected remedial action utilizes permanent
solutions and considered the use of alternative treatment
technologies to the maximum extent practicable. The original
remedy, as modified by Alternative 12 of this ROD Amendment,
protects human health and the environment, is cost-effective and
addresses the CERCLA statutory preference for treatment. Since
wastes will be left in place on-site, a review will be conducted
to ensure that the remedy continues to provide adequate
protection of human health and the environment within five years
after co; .encem.. ; of the remedial action, in ac ^rdance with
CERCLA and the NCP (40 C.F.R. Part 300). As stated at various
points earlier in this ROD Amendment, the U.S. EPA will
determine, in connection with the five-year review process,
whether the contingent pump-and-treat system of this remedy will
need to be implemented.
Woodstock ROD Amendment
July 1998 47
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FIGURES
WOODSTOCK MUNICIPAL LANDFILL SUPERFUND SITE
WOODSTOCK, MCHENRY COUNTY, ILLINOIS
JULY 1998
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SOURCE
USGS TOPOGRAPHIC MAP
WOODSTOCK. UL QUADRANGLE
figure 1
SITE LOCATION
WOODSTOCK MUNICIPAL LANDFILL SITE
Woodstock, Illinois
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ea^wa ^m&% ?
'-. /^/c7--^?S-^ L » ^N i ^-j ' fa ) ) '•' 'i<2C> <~j ^ .O-xif^S 'Or'i V\ ,'!//_ /• j^, fen ' I
yf^^^i/iHJ
LEGEND
PROPOTY BOUNDARY LINE
y»-.J.* UOMfTORING WELLS INSTALLED DURING Rl
MW-U > - SHAU.OW WELL
d - DEEP WELL
p - P€AT WELL
PZ-t. PIEZOMETER INSTALLED DURING PCX
P-1 A PC2C-ETER INSTAUED DUMNC Rl
SC-2 O STAfF GAUGE INSTALLED DUONG PtX
MW-140 UONITORMG WELL MSTAILED DURING PCX
CW-1© EXTRACTION WELL INSTALLED DURING PO
figure 2
SITE PLAN AND PROPERTY BOUNDARIES
WOODSTOCK MUNICIPAL LANDFILL SITE
Woodstock, Illinois
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APPENDIX A
RESPONSIVENESS SUMMARY
WOODSTOCK MUNICIPAL LANDFILL SUPERFUND SITE
WOODSTOCK, MCHENRY COUNTY, ILLINOIS
JULY 1998
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APPENDIX A
WOODSTOCK MUNICIPAL LANDFILL RESPONSIVENESS SUMMARY
This Responsiveness Summary addresses concerns expressed by the public and governmental
bodies in written and oral comments received by the United States Environmental Protection
Agency (the U.S. EPA or the Agency) regarding the Proposed Plan for a Record of Decision
(ROD) Amendment for the Woodstock Municipal Landfill Superfund Site (the Site), Woodstock,
McHenry County, Illinois; CERCLIS ID # ILD 980 605 943; Site Spill ID # 05DB.
Community Relations Background
The U.S. EPA released the Proposed Plan for a ROD Amendment for public review on
February 23, 1998. A copy of the Proposed Plan was mailed to all residents in the Site area. The
30-day public comment period on the Proposed Plan was opened on February 23, 1998, and
originally was to close on March 24, 1998. A public meeting was held at the Woodstock Public
Library, 414 West Judd Street, Woodstock, Illinois, 60098, on March 4, 1998, to explain the
alternatives evaluated in the Proposed Plan, to explain potential health risks, and to discuss the
proposed alternative. An advertisement was placed in the February 25, 1998, editions of the
Northwest Herald and the Woodstock Independent, to announce the public comment period and
meeting. A question and answer period was included in the meeting, along with the formai
comment period. During the public meeting, the U.S. EPA announced that the public comment
period would be extended for an additional 15 days, to April 8, 1998. A second ad was placed in
the March 20, 1998, edition of the Northwest Herald and the March 25, 1998, edition of the
Woodstock Independent, to announce the extension of the public comment period.
Summary of Significant Comments
Comments Received During the March 4. 1998. Public Meeting
Con nt #/: The residents of Woodstock have been informed often by the <"ity of Woodstock
that the la>^.jill projL-Lt was going to cost approximately SI 1 million, and that tk^ cost would be
shared equally between AlliedSignal and the City, since no other party has come forward to
admit responsibility. The numbers we 're now seeing do not add up to SI I million. It appears,
instead, that the modified project will cost approximately S4.5-million. Can you explain the
discrepancy?
U.S. EPA's Response: The City of Woodstock, Illinois (the City) would probably be the best
place to go for a further explanation of these numbers, and how they were derived. However, it
appears that the $1 l-million figure isa result of adding up the ~-$3-million costs of the Remedial
Investigation (RI) and Feasibility Study (FS), plus the estimated ~S8-million costs for the
original remedy from the June 30, 1993, ROD. The original ROD remedy estimated costs were
based on the RI/FS estimates, which are generally considered to be within a 70 percent to 150
percent range of the actual costs. In addition, the cost of landfill capping materials have gone
down in the last 4-5 years due to competition in the market place. Given the facts that the ROD
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WOODSTOCK RESPONSIVENESS SUMMARY (Continued)
Amendment changes have reduced the cost of the remedial action by altering the profile of the
landfill cap, and the groundwater pump-and-tn;at portion is a contingent part of the remedy, and
that the cost-estimates for this ROD Amendment are more precise than those provided in the
Rl/FS, the current cost is more in the range of $7.5-million ($3-million for RI/FS. plus $4.5-
million for the RA), rather than the $11-million figure provided by the City (SS-million for
RJ/FS, plus approximately SS-million for the RA); and estimated savings to the PRPs of
approximately $3.5-million.
Comment #2: The City has proposed a waste transfer station to be built on the Site.
The City has passed legislation suggested by the U.S. EPA that prevents building on the Site for
99 years. Why should the City be allowed to build a waste transfer station now? If this Site is
hazardous because of waste that was placed in the landfill, why would we want to pu. mere
waste on the same site, even as part of a transfer station/ H c ui e concerned about wet and
leaking material migrating from trucks carrying wastes to and from the transfer station. Local
residents are also concerned about the odor problems associated with waste transfer stations.
U.S. EPA's Response: The U.S. EPA is aware that the City has passed certain legislation to
ensure that the physical and structural integrity of the cap and its components are not
compromised after construction. The City was required to take such measures pursuant to the
terms of the Unilateral Administrative Order (UAO) for Remedial Design and Remedial Action
issued by the U.S. EPA on September 2, 1994.
The U.S. EPA supports the reuse of Superfund Sites, particularly where a governmental body
may be in a position to generate income from such reuse, thereby recouping the costs of
construction. This position is consistent with the U.S. EPA's Brownfields initiative. The U.S.
EPA, therefore, would not object to the City building a waste transfer station or making use of
the Site in some other way, provided that when the landfill cap is being designed, the waste
transfer station or other facility that is being contemplated is taken into account, so that the U.S.
EPA can review the remedial design and ensure that appropriate engineering concerns are taken
into consideration prior to the initiation of any construction.
A waste transfer station is a facility where smaller garbage trucks hauling principally municipal
waste dump their waste loads, to be gathered and put on larger trucks prior to transfer to a
landfill. Like the commenter, the U.S. EPA would particularly be concerned with any reuse of
the Site where leachate, run-off, or other liquid wastes might have the potential to be discharged
onto the Site and percolate into the landfill. Any such waste water would need to be properly
handled and disposed of in accordance with applicable Federal. State, and local regulations.
The U.S. EPA does not regulate odors. I would recommend that you take up your concerns
regarding odor directly with the City. In addition, please be advised that the Illinois Pollution
Woodstock ROD Amendment
July 1998 RS -2
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WOODSTOCK RESPONSIVENESS SUMMARY'rContinuedl
Control Board (IPCB) has regulations in place v\ ith which the City would need to comply prior
to implementing a waste transfer station, and the IPCB may also be of assistance to you in this
matter.
Comment #3: Will the change in the landfill design require some kind of variance from the state,
from state standards or from federal landfill standards; or is this all just done as part of the
Record of Decision?
U.S. EPA's Response: The U.S. EPA and the Illinois Environmental Protection Agency (1EPA),
along with AlliedSignal and the City, the potentially responsible parties (PRPs) for this Site,
have worked very closely together to come up with a design thaj is environmentally acceptable.
that protects human health and the environment, and truly addresses the technical requitements
for a landfill cap at this Site, based on the additional studies that have been done. No waivers
from state or federal standards are necessary, since all applicable or relevant and appropriate
requirements will be met. The reason that this particular landfill cap profile was not proposed in
the original ROD is that the additional information and data that supports this ROD Amendment
was not available at the time the original ROD was signed on June 30, 1993. The IEPA has
concurred with this ROD Amendment.
Comment #4: So there is no further action needed other than amending the ROD?
U.S. EPA's Response: Since the studies supporting this ROD Amendment have been completed
and submitted by the PRPs, and approved by the U.S. EPA, no any additional studies will be
required prior to the initiation of the remedial design.
Comment #5: Do you have studies documenting how natural attenuation is addressing the vinyl
chloride?
U.S. EPA's Response: The Predesign Investigation (POI) Report, along with the quarterly
groui .vater monitoring results provided by the PRPs, indicate that there has been a reduction in
the concentration of vinyl chloride since the U.S. EPA first began investigating the Site. As part
of the PDI Report, the extent of the vinyl chloride plume has been better delineated. It appears
that the plume is much smaller than was originally believed. The purpose of making the
groundwater pump-and-treat a contingent part of this ROD Amendment is to allow for additional
monitoring to verify that natural attenuation is indeed occurring.
Comment #6: What is the mechanism that has resulted in the reduction in the vinyl chloride
concentration? Is it dilution? Is it bioremediation? What is it?
Woodstock ROD Amendment
July 1998 RS -3
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WOODSTOCK RESPONSIVENESS SUMMARY (Continued!
U.S. EPA's Response: The U.S. EPA cannot give a definitive answer regarding the exact
mechanism that is causing the apparent reduction in the concentrations of vinyl chloride. It is
generally believed that the wetlands provide a (biochemical) 'reducing' environment, due to the
presence of peat. It is thought that the vinyl chloride is passing through the peat layer and, in the
process, is being attenuated. One of the poten'ial breakdown pathways for vinyl chloride is a
microbial dehalogenation to ethylene, and subsequent breakdown to carbon dioxide and water.
The long-term monitoring program that will be conducted will provide analytical answers and
will provide the necessary verification that the vinyl chloride concentrations are indeed
decreasing at an acceptable rate.
Comment #7: Is (he U.S. EPA 's new guidance on natural attenuation the reason that you can
nov. select natural attenuation as the remedy for the contaminated groundwaier, making the
pumj;-and-treat system a contingent part of the remedy, whereas in 1993 you could not?
U.S. EPA's Response: Yes. Based upon the experience of the Superftmd Program, new
guidance was issued by the U.S. EPA in December 1997 that allows the Agency to pursue this
course of action.
Comment #8: Who will pay for the long-term monitoring, the City or the agencies?
U.S. EPA's Response: The PRPs will pay the costs of the remedial action, including the long-
term monitoring program for natural attenuation, which is estimated at approximately $10,000
per year.
Comment #9: In 1993 the McHenry County Defenders recommended that the U.S. EPA consider
using a native prairie as part of the landfill cap cover. 'I'm wondering what has happened with
that proposal.
U.S. pPA's Response: The Agency has taken up your suggestion on native prairie grasses, and
established i interagei.., agreement with the Natural Resource Conser,"...ion Service, formerly
known as the Soil Conservation Service. The local district office is assisting us in looking into
all of the variables that would be conducive to growing natural prairie grass at the Site. One of
the concerns the Agency has with respect to natural prairie grass is that it generally has a very
deep rooting zone, which explains in part why this type of grass is able to survive drought
periods. The U.S. EPA would be concerned about any vegetation that could penetrate the landfill
cap with its root system. As work on the new landfill cap design proceeds, the U.S. EPA will
need to take a second look at the natural prairie grass issue and make a decision on whether or
not it is viable. If it is viable, the U.S. EPA will pursue it. If it is not viable, then it won't be
further considered.
Woodstock ROD Amendment
July 1998 RS -4
-------
WOODSTOCK RESPONSIVENESS SUMMARY (Continued!
Comment #10: Once the ROD Amendment is signed tow soon would construction begin on (he
landfill cap?
U.S. EPA's Response: The U.S. EPA, the IEPA, and the PRPs have worked through the ROD
Amendment process in a very cooperative fashion. The PRPs are currently subject to a UAO
under Section 106 of the Comprehensive Environmental Response, Compensation and Liability
Act (CERCLA or Superfund). It is anticipated that all of these same parties will continue to
work together cooperatively to revise the UAO and the Scope of Work as necessary.
Alternatively, the United States may seek to negotiate a Consent Decree for Remedial Design
and Remedial Action.
It is hoped that the remedial design will be rather straightforward and will lead quickly to
remedial action. The U.S. EPA would like to see remedial action commence by no later than the
Spring or Summer of 1999.
Comment #11: What other type of use can the landfill be put to once it is covered? Would it be
possible that the property could be put to some use, other than a waste transfer station, such as a
golf course or a school bus parking lot? Of course these uses present some of the same problems
as those presented by a waste transfer station, i.e. the need for constructing a building (footings,
etc.).
U.S. EPA's Response: As stated above, the U.S. EPA supports reuse of this Site consistent with
the ROD Amendment, provided that any proposed use is planned and designed into the overall
remedy. One of the options that the PRPs have in designing the overall remedy is to consolidate
waste, i.e.. perhaps there are some areas of the Site where the waste is not as deep as in other
areas, and the waste from those areas of the Site may be removed and placed in another area to
reduce the areal extent of the cap. This approach may free up a part of the property for
construction of.a building. The U.S. EPA does not dictate how a landowner should reuse a Site,
once remediated. However, any reuse of the Site wouM be subject to approval to ensure that it is
in complia j with tho ROD Amendment and environmentally acceptable.
Comment #12:1 am aware (hat the City has allowed many hundreds of dump trucks to dump soil
right in the area you have pointed out. Is this soil now considered contaminated? Or, can it be
used ax part of the new landfill cap?
U.S. EPA's Response: The soil that has been stockpiled on the Site was tested before it was
bought on-site. The soil complied with all applicable federal and state requirements. In addition,
to ensure that the soil would not become contaminated, a barrier layer was placed underneath that
soil. That soil was brought on-site principally as additional fill material to be placed when the
landfill cap is constructed.
Woodstock ROD Amendment
July 1998 RS-5
-------
WOODSTOCK RESPONSIVENESS SUMMARY fContinuedl
Comment #/3:1 am aware that there is groun,', water contamination on the site. Is there also
groundwater contamination off-site, and if so where? Are there monitoring wells off-site? Is i!
true that there is no restriction on the use of wells surrounding the site [for potable waterJ?
U.S. EPA's Response: There are monitoring wells off-site, and the U.S. EPA has observed no
contamination in the off-site monitoring wells. Groundwater in the area flows generally toward
the Kishwaukee River (the River), which acts as a hydrogeologic barrier. The groundwater does
not flow from north of the River, underneath the River, and then south of the River (i.e., it does
not pass underneath the River). Based on the additional monitoring that has been done, the U.S.
EPA believes that the vinyl chloride contaminated groundwater is essentially a stagnant pool,
which is actually one of the reasons why the Agency is in favor of looking further into natural
attenuation. If this were a moving plume, or if the river were not where it is. the U.S ;£PA's
decision might have been otherwise.
Comment #14: So there aren't any restrictions for the use of wells off the site? Would the U.S.
EPA allow new residential wells, to be located some distance from the Site, to be constructed?
U.S. EPA's Response: There are no restrictions on existing residential wells for potable water.
Regarding additional off-site residential wells, it would depend on where they would be placed.
No residential monitoring wells may be placed on the Site. In addition, since the vinyl chloride
plume has not been fully delineated, the U.S. EPA would not allow the placement of residential
wells in close proximity to the Site.
Comment #/5: / am very concerned about the proposal to put a waste transfer station at the
Site. I understand (hat approximately 400 garbage trucks a day would be going to the facility. If
that is the case, w.on 't you need a good-sized parking lot, with a retention pond and a retention
area (to hold the water from the retention pond) so that the water does not migrate to the creek?
I am also very concerned about the fact that garbage trucks often appear to be dripping
chemicals, brake fluid, antifreeze, and gasoline. All of these materials are likely to drip onto any
parking lot at the transfer facility, and then migrate into a retention pond and again into the
ground there.
U.S. EPA's Response: If and when the City does submit the plans for either a waste transfer
station or other facility that would reuse all or a portion of the Site, the U.S. EPA will ensure that
any leachate, run-off, or waste waters generated will be taken into account and dealt with
appropriately in accordance with all relevant state and federal laws. At this point, however, the
U.S. EPA has not been formally notified of any final decision by the City to reuse the Site as a
waste transfer facility. In the event that any reuse of the property is proposed as part of the
Remedial Design, the U.S. EPA will ensure that such reuse will not contribute new hazardous
Woodstock ROD Amendment
July 1998 RS -6
-------
WOODSTOCK RESPONSIVENESS SUMMARV'rContinuedl
materials to the Site, will fully comply with the ROD Amendment, and will not jeopardize the
integrity of the remedy.
Comment #16: 1 have lived adjacent to the Site for over fifty years, on the same highway. I am
very concerned about the odor that- would accompany any waste transfer station. The prevailing
winds in the summer come from the southwest. If all those trucks were to go to the Site dripping
and changing their wastes from one load to another, the entire area will stink horribly. When
the dump was active no one could open a window because the smell was so bad. We now have
two motels. We have all those businesses, restaurants and everything out near the Site, and more
are coming. I am concerned that if the waste transfer facility is built, the odor will have a
serious effect on those businesses. I hope you take that into consideration.
U.S. EPA's Response: The U.S. EPA understands your concern about potential odors from a
waste transfer facility but, as stated above, the U.S. EPA does not regulate odors. However, as
also noted above, the U.S. EPA has not been formally notified of any final decision by the City
to construct a waste transfer facility at the Site. If the PRPs eventually develop such a plan, the
U.S. EPA recommends that you take up your concerns regarding odor directly with the City. In
addition, please be advised that the IPCB has regulations in place with which the City would
need to comply, and the IPCB may also be of assistance to you in this matter.
Comment #1 7: The McHenry County Defenders support the proposed amendments to the Record
• of Decision for the Woodstock landfill. We hope it will be done quickly and that the cap will be
constructed as soon as possible. We would like to renew our request that the agency look into an
enhanced natural attenuation process or experimental biore mediation program at this Site.
Because of the nature of the vinyl chloride contamination and the location it is in. i.e. the
wetlands, it lends itself very well, we think, to some experimental program where you can
actually speed up this natural attenuation that's going on. We'd rather see it speeded up than
just monitored for 100 years. And. finally, we urge you to take a second look at using native
plant? ^rairie plants, on the landfill cover.
U.S. EPA's Response: The U.S. EPA anticipates that the natural attenuation of the vinyl
chloride plume should take approximately 20 to 25 years, which is comparable to the anticipated
time-frame for a pump-and-treat remedy. In the event that it becomes apparent that the natural
attenuation will take longer than the 20 to 25 years, the U.S. EPA will consider other alternatives
for remediating the vinyl chloride plume, including implementing the design and construction of
the pump-and-treat remedy. The U.S. EPA is working with the Natural Resource Conservation
Service, formerly known as the Soil Conservation Service, to investigate the viability of the use
of growing natural prairie grass at the Site. The U.S. EPA's position with regard to natural
prairie grass is stated in the response to Comment 9.
Woodstock ROD Amendment
July 1998 RS-7
-------
WOODSTOCK RESPONSIVENESS SUMMARY fContinued)
Comment # 18: How long after this public hearing process is complete can we expect to see work
(other than well construction) started at the Site?
U.S. EPA's Response: The U.S. EPA cannot definitely state on what date construction of the
landfill cap will commence but, as stated above, the Agency hopes to see construction start no
later than the Spring or Summer of 1999. With the issuance of the ROD Amendment and this
Responsiveness Summary, the remedy selection process is complete. Now, either the United
States will negotiate a Consent Decree or the U.S. EPA will revise the UAO as necessary. Since
a significant amount of discussion has already taken place amongst the U.S. EPA, IEPA and the
PRPs, Remedial Design should be quick. As soon as Remedial Design is finished, Remedial
Action can commence. Depending on weather conditions, among other things, it may be
possible that some Remedial Action could occur before the end of the construction season in
1998.
Comment #19: What is vinyl chloride?
U.S. EPA's Response: Vinyl chloride is an organic compound that is lighter than water. It is a
colorless gas with a mild, sweet odor. The odor threshold for vinyl chloride is 3,000 parts per
million (ppm). It is slightly soluble in water and quite flammable at levels of 30,000 ppm and
higher. The chemical formula for vinyl chloride is C2H3CI and the molecular weight is 62.5
g/mol. Trade names and synonyms for vinyl chloride include: Chlorethene; Chlorethylene;
Monochloroethene; Monovinyl chloride (MVC); and Trovidur. At this Site, vinyl chloride is
most likely a breakdown product from trichloroethylene or perhaps even perchloroethylene (aka
tetrachloroethylene), a solvent that was placed in the landfill years back. Vinyl chloride is one of
the last steps in the degradation pathway. One of the reasons why the U.S. EPA feels that natural
attenuation is a viable alternative is the fact that the precursors of vinyl chloride are not being
detected in the leachate produced by the landfill. So we suspect that we are at the very tail end of
this whole breakdown process.
Comment #. : Once in. :ap has been put on the lar Jfill, how long will.. je before it is safe?
How many years approximately?
U.S. EPA's Response: There will be a 30-year period under the UAO (or Consent Decree)
where the cap would need to be annually inspected and repaired if necessary, and some form of
monitoring would be required. Initially, monitoring will probably be required quarterly, and then
it would be reduced appropriately based on the analytical results. Once the landfill cap is in
place, the pathways (inhalation, ingestion, dermal, etc.) causing the imminent and substantial
endangerment to human health and the environment, will have been eliminated.
Woodstock ROD Amendment
July 1998 RS -8
-------
WOODSTOCK RESPONSIVENESS SUMMARY (Continued^
Comment #21: If prairie grasses are used to cover th.' cap, I hope, that the grass would not have
to be mowed, fertilized or treated with herbicides to control weeds. My fear is that all of these
products would wash into the Kishwaukee River, causing more contamination.
U.S. EPA's Response: This is an issue that the PRPs need to discuss further with the U.S. EPA.
The U.S. EPA will evaluate the use of natural prairie grasses from the standpoint of
the environment, as well as cost-effectiveness.
Comment #22: What distance away from the landfill would you recommend for construction of a
park? I do not mean to suggest that the park would be built directly on the landfill, but rather it
would abut very near the southwest corner where the Kishwaukeg cuts that corner off.
U.S. EPA's Response: As stated above, there will be a 30-year ptiiod under the UAO (or
Consent Decree) where the cap would need to be annually inspected and repaired if necessary,
and some form of monitoring would be required. But once the landfill cap is in place, the
pathways (inhalation, ingestion, dermal, etc.) causing the imminent and substantial
endangerment to human health and the environment will have been eliminated.
If the City proposed placing a park on the Site, the U.S. EPA would need to assess the potential
risks to children in the event that they, for example, were to dig up the landfill cap and be
exposed to the landfill waste. If a park were placed anywhere outside the Site boundaries, the
U.S. EPA would need to evaluate any potential risks from a "trespasser" scenario.
Comment #23: What are the problems with vinyl chloride? How does it affect humans?
U.S. EPA's Response: Vinyl chloride is a colorless gas with a mild, sweet odor. It is does not
occur naturally in the environment. Vinyl chloride that enters drinking water comes from
factories that release wastes containing it into rivers and lakes or from seepage into underground
water in areas where -^emical wastes containing it are stored or have been disposed, such as at
this Site. x \h respec' to the vinyl chloride contamination at this Site, it appears .0 be a
degradation product of trichloroethylene in groundwater. Vinyl chloride rapidly evaporates from
water, but generally does not degrade there, unless there are conditions present in the area of
contamination that would favor natural attenuation. Vinyl chloride will not accumulate in
aquatic life. Vinyl chloride has been found in at least 133 of 1177 hazardous waste sites on the
National Priorities List.
Exposure Pathways
Humans are exposed to vinyl chloride from environmental and occupational sources. The most
likely way that vinyl chloride can enter your body is from breathing air containing it. This
exposure pathway is of concern for persons employed in vinyl chloride manufacturing or
Woodstock ROD Amendment
July 1998 RS -9
-------
WOODSTOCK RESPONSIVENESS SUMMARY rContinued)
processing, for people living in communities where vinyl chloride plants are located, and for
individuals living near hazardous waste disposal sites. Vinyl chloride can also enter your body if
you eat food or drink water containing it. Passage of vinyl chloride through the skin (dermal
absorption) is not likely to be an important pathway.
Short-term Exposure Effects
Acute (short-term) exposure to high levels of vinyl chloride in air has resulted in central nervous
system effects (CNS), such as dizziness, headaches, and giddiness in humans. Short-term
exposures to very high levels of vinyl chloride in air can cause dizziness, stumbling and lack of
muscle coordination, headache, unconsciousness, and death. Vinyl chloride is reported to be
slightly irritating to the eyes and respiratory tract in humans.
Long-term Exposure Effects
Liver damage may result from long-term (chronic) exposure to vinyl chloride in humans, through
both inhalation and oral exposure. Inhaled vinyl chloride in humans has been shown to increase
the risk of a rare form of liver cancer (angiosarcoma of the liver). Vinyl chloride exposure,
through inhalation, has also been associated with cancer of the brain, lung, and digestive tract in
humans. The U.S. EPA has not assessed the reproductive'/developmental toxicity data for vinyl
chloride. There are positive human and animal studies showing adverse effects which raise a
concern about potential reproductive and developmental hazards to humans from environmental
exposures. Based upon available studies and data, it would be prudent to consider vinyl chloride
as posing both reproductive and developmental hazards.
Regulated Levels
In 1974, Congress passed the Safe Drinking Water Act. This law requires the U.S. EPA to
determine safe levels of chemicals in drinking water which do or may cause health problems.
These non-enforceable levels, based solely on possible health risks and exposure, are called
Maximum Contaminant Level Goals (MCLGs). The MCLG for vinyl chloride has been set at
zero because the U.S. EPA believes this level of protection would not cause any of the potential
health problems described above. Based on this MCLG, the U.S. EPA has set an enforceable
standard called a Maximum Contaminant Level (MCL). MCLs are set as close to the MCLGs as
possible, considering the ability of public water systems to detect and remove contaminants
using suitable treatment technologies. The MCL has been set at 2 parts per billion (ppb) because
the U.S. EPA believes, given present technology and resources, this is the lowest level to which
water systems can reasonably be required to remove this contaminant should it occur in drinking
water. The U.S. EPA stated that community drinking water systems that regularly serve the
same 25 persons for at least 8 months of the year must limit vinyl chloride in the drinking water
to 2 ug/L (2 ppb), starting January 9, 1989.
Woodstock ROD Amendment
July 1998 RS-10
-------
WOODSTOCK RESPONSIVENESS SUMMARV'fContinued)
Comment #24: RECOMPACTION OF THE EXISTING LA YER
The proposed remedy includes " Recompacting the top 12 inches of the existing cover to within
95 percent compaction. " Conestoga-Rovers & Associates (CRA), consultant to the PRPs, agrees
that recompaction of the regraded layer will be necessary prior to placement of additional
capping materials, however, compaction of this material to within 95 percent compaction
(assumed to be Standard Proctor Density ("SPD ")) may not be attainable due to the
heterogeneous nature of the existing cover.
A more realistic goal would be to recompact the regraded existing cover material to the greatest
extent practical. Compaction of the existing cover is intended to provide a working base which
to construct the landfill '-over.
As such, CRA recommends that the language of the proposed plan be revised to state
"Recompacting the top 12 inches of the existing cover to the greatest extent practical or by
passing over the regraded area a minimum of three times with a vibratory compactor of at least
10 tons total weight.
U.S. EPA's Response: The U.S. EPA has modified the compaction requirement language of the
ROD Amendment to read, "...recompacting the top 12 inches of the existing cover to within 95
percent compaction, if practical, but at least to a degree equal to or greater than that provided by
passing over the regraded area at least three times with a vibratory compactor of at least 10 tons
total weight." The requirement for recompaction of the top 12 inches of the existing cover is
intended to provide a firm soil foundation for installing the landfill cover. The U.S. EPA concurs
with CRA's recommendation that three passes of a vibratory roller, of at least 10-ton total
weight, over the existing cover soil is likely to provide a soil foundation firm enough for
installing the landfill cover in most areas of the landfill. More particularly, the U.S. EPA agrees
that the compaction requirement of this remedy can be qualified by "practicality," and further
agrees that a good measi'rp of "to the extent practical" is the extent to which the regraded
mate 's can ue compacted after three passes with a vibratory compactor 01 at least 10-tons total
weight.
Comment #25: SLOPE OF THE FINAL LANDFILL COVER GR.4DE
The proposed remedy includes "Final grading of the total cover to no less than 2.0 percent
slope, after accounting for anticipated settlement. "
The qualifier "...after accounting for anticipated settlement" suggests that the minimum slope
should he greater than 2.0 percent after cap construction in order to allow for some settlement.
Woodstock ROD Amendment
July 1998 RS-11
-------
WOODSTOCK RESPONSIVENESS SUMMARY (Continued)
CRA believes that a 2.0 percent minimum slope afte • cap construction will account for any future
settlement.
CRA has prepared a technical memorandum (attached) which discusses the amount of landfill
cap settlement to be expected for the new landfill cap. Through our calculations, we [CRA]
anticipate that the maximum cap settlement should be no greater than 0.44 feet which would be
generally uniform across the landfill surface since the waste thickness is generally uniform. As
such, it is anticipated that the final average slope would still_ be 2 percent. Localized differential
settlement of approximately half of G.44 feet (0.22 feet) is ^xpecizd and these areas would be
repaired as part of the landfill cap operation and maintenance (G&M) program, if ponding
areas are created. Differential settlement would be expected regardless of the slope and the
amount of settlement and would require repair under any slope specification.
As such, CRA recommends that the proposed plan be revised to state "Final grading of the covet-
to be designed to no less than 2.0 percent slope. "
U.S. EPA's Response: The requirement for establishing a minimum slope after accounting for
the anticipated settlement of the surface and subgrade of the landfill cover is intended to provide
for rapid removal of water on the landfill cover and in the drainage layer of the cover. The U.S.
EPA's guidance for constructing landfill covers recommends a minimum three (3) percent slope
after accounting for anticipated settlement. In the case of this Site, the U.S. EPA has already
reduced the minimum slope requirement from three (3) to two (2) percent. Any settlement of
landfilled waste will further reduce the slope, resulting in excessive retention of water on the
landfill cover and in the drainage layer of the cover. Therefore, in this case, the U.S. EPA cannot
accept the language change recommended by CRA.
Woodstock ROD Amendment
July 1998 RS-12
-------
APPENDIX B
ADMINISTRATIVE RECORD
WOODSTOCK MUNICIPAL LANDFILL SUPERFUND SITE
WOODSTOCK, MCHENRY COUNTY, ILLINOIS
JULY 1998
-------
U.S. EPA ADMINISTRATIVE RECORD
WOODSTOCK MUNICIPAL LANDFILL
WOODSTOCK, ILLINOIS
ORIGINAL
O4/07/93
DOM DATE AUTHOR RECIPIENT TITLE/DESCRIPTION PAGES
ssss r=== sssrss sssxxss-3 ====s=s=sr======- ssssr
1 00/00/00 Miscellaneous Newspaper Articles, Various 13
Dates
2 00/00/71 Hughes, 6.H., et al, U.S. EPA Hydrogeology of Sclid Haste Disposal Sites in 153
Illinois State Northeastern Illinois
Geological Survey
i
3 00/00/84 Nicholas, J.R., and Report Entitled, 'Water in Sand and Grave! 41
Krohelski, J.T., Deposits if, fi^Henry County, Illinois'
U.S. Geological
Survey
4 09/05/84 Bates, E., U.S. EPA Preliminary Assessient 6
and dinner, L., IEPA
5 04/29/85 Bachunas, C. i Nelson, S., U.S. EPA Review of Sample Case I 4042 Lou Soil totals 12
Pratl, A., Ecology *
Environment, Inc.
6. 05/22/85 Bachunas, C. I Nelson, S., U.S. EPA Review of Saiple Case 14042 Lou Soil Organic 26
Pratl, A., Ecology t
Environment, Inc.
7 08/02/85 Divner, L., IEPA and Site Inspection Report 24
Nelson, S., U.S. EPA
8 06/06/86 Beaie, J., Allied U.S. EPA Cover Letter for Completed EPA Form- 8900 2
Automotive 1 Notifications
9 10/02/87 U.S. EPA MRS Scjring Package 91
10 00/00/88 Holm, H., tteston Faryan, S., U.S. EPA Site Assessment 17
11 07/00/88 Hell Sampling Data from 7/B8 83
12 07/22/88 Suburban Laboratori- Analysis of Organic Chemical Compounds by Gas 15
es, Inc. Chromatography/Hass Spectrometry: Final
Report
13 08/04/88 Suburban Laboratori- Roy tieston, Inc. Analysis of Samples Received 7/22/B8 7
es, Inc.
-------
DOCI DATE
AUTHOR
RECIPIENT
TITLE/DESCRIPTION
14 12/00/88
IS 12/00/88 Tsai, C.
16 01/00/89 Tsai, C
U.S. EPA
U.S. EPA
U.S. EPA
17 01/03/89 Suburban Laboratory Hatz, S., Roy F.
es, Inc. Heston, inc.
18 02/12/89 Nelson, R., U.S. D01 Swale, R., U.S. EPA
19 05/00/89 Tsai, C. U.S. EPA
20 05/24/89
Niedergang, N., U.S.
EPA
21 06/09/89 U.S. EPA
22 06/19/89
Schaefer, R. and
Side, N., U.S. EPA
23 06/2&/89 Child, N., IEPA
24 07/26/89
Hoeller, D., Arrow
Aluminum Castings,
Inc.
PRPs
Haste Management of
Illinois, Inc.
U.S. EPA
Constantelos, B.,
U.S. EPA
Hatts. 6.H.. U.S.
EPA
Chain of Custody Record for Sampling 24
6uidanc>: "Standard Operating Procedure for 45
the Analysis of Semivolatile Organics in
Drinking Hater...'
Guidance: 'Standard Operating Procedure for 35
the Anaiysis of Pesticides/PCBs in Hater Kith
LON Detection Levels,' Revised
Analysis of Saiples Received 12/22/88 6
U.S. DOTs Couents on the RI/FS Plan 3
i
Guidance: 'Standar. Operating Procedure for 41
the Analysis of Volitile Organics Hith LON
Detection Liiits...,' Revised
Letter of Potential Liability 7
Notification of Hazardous Haste Site
Region V Municipal Settlement Guidance 10
Amendment to the Enforcetent Hulti
Site Cooperative Agreement
Response to 104(e) Information Request,
Request Forwarded to Previous Owner
25 08/16/89
26 08/31/89
Straw, A., Haste
H«—jement of
Illinois, Inc.
Caldwell, H., City
of Noodstock
Fulqhum, N., U.S.
EPA
Swale, R. and
Fulghui, II., U.S.
EPA
FOIA Requesting Linking Documentation
Regarding ..ite Management
Letter re: RecoMendation That Client Approve
8/28/89 Draft Consent Order
27 09/01/89
Haher, L, Croier,
Eaqlesfield I Naher
Swale, R. and
.Fulghui, N., U.S.
EPA
Letter re: Recommendation That Client Sign
8/28/89 Draft Consent Order
28 09/19/99 U.S. EPA
Respondents
Administrative Order By Consent, Signature
Pages
-------
DOCI
AUTHOR
fiECir iEST
TITLE-DESCRIPTION
29 09/19/89 Hc6uire, «.
30 09/24/89 U.S. EPA
31 09/29/89 U.S. EPA
32 09/29/89 U.S. EPA
U.S. EPA
Respondents
Respondents
33 10/02/89 Garry, R., John J. Fulghui, H., U.S.
Horeled Law Office EPA
34 10/02/89 U.S. EPA
35 12/05/89 Nelson, R., U.S. DOI Swale, R., U.S. EPA
36 12/06/89 Clay, D., U.S. EPA U.S. EPA
37 12/27/89 Marzyn, Inc.
U.S. EPA
38 03/06/90 Swale, R., U.S. EPA Vagt, P., Warzyn
Inc.
39 04/00/90 'Marzyn Inc. U.S. EPA
40 04/00/90 Harzyn Inc. U.S. EPA
41 04/00/90 Nan.n Inc. U.S. EPA
42 04/09/90 Versar, Inc. U.S. EPA
43 04/20/90 Warzyn, Inc. U.S.EPA
44 06/00/90 U.S. EPA
45 06/03/90 Angstiann, J., U.S. EPA
Versar, Inc.
Reii.hert Chevrolet t flldsmobile Sales, Inc. 5 2
Signature Agreeing to the Consent Order
Administrative Order By Consent, fliendtent tl 8
Adiinistrative Order By Consent for RI/FS, 49
Final
News Release: 'EPA Identifies 9 Net. Midwest 1
Sites for Superfund Cleanup*
Letter Requesting That Arrow Aluiinui 3
Castings, Inc. Be lie'.eased From Liability
Hews Release: "City of Woodstock, Allied 1
Chemical Corp. and Uthers Agree to
Investigate the Woodstock Municipal Landfill
Site1
Response to Request for Information on 4
Wetlands
Guidance: 'Interii Policy on CERCLA 33
Settlements Involving Municipalities or
Municipal Hastes,1 OSVER Directive 19834.13
flap: RI/FS-Site Base.Hap with 100 Foot Surve- 10
y Grid
U.S. EPA's Review Comments Concerning the 37
RI/FS Planning Documents
QAPP, Vol. 1 of 3, Kith Appendices A, 8 and C 360
QAPP, Vol. 2 of 3, Appendices D, E and F 445
QAPP, Vol. 3 of 3, Ap. .ice- fi, H, 1, J, K, 330
and L
Technical Oversight Data Quality Objectives 1
Nap: RI/FS-Site Base Rap Showing Coordinates- 10
i Saipling Locations
Fact Sheet: 'Superfund Study Begins at 8
Woodstock Municipal Landfill"
CoMunity Relations Plan, Final Plan 27
-------
DOC* DATE AUTHOR RECIPIENT TITLE/DESCRIPTION PA6E5
46 06/18/90 La Faire, H., U.S. Lesser, T., U.S. EDP r^,,ort on Public Neeting Held 6/13/90 4
EPA
47 07/24/90 Harzyn, Inc. U.S. EPA Inorganic Analysis Data Sheets 3
48 07/24/90 Compuchem.rtp U.S. EPA Volatile Organic* Analysis Data Sheets 2
49 08/08/90 Nariyn, Inc. U.S. EPA Inorganic Analysis Data Sheet Narked 8
'Leachate Data'
50 08/13/90 Bosse, «., Versar Swale, R., U.S. EPA Fax Cover with Boring Logs Froi 7
Inc. B/l/90-8/13/90
51 08/15/90 Harzyn, Inc. Dra»tny of X-Secljions 2
52 08/2n/90 Clay, 0., U.S. EPA U.S. EPA OSHtR Directive No. 9835.15: 'Performance of 4
Risk Assessment *,v Remedial
Investigation/Feasibility Studies Conducted
by MPs'
53 10/17/90 Naher, K., Croier, Swale, R., U.S. EPA Notice of Force Najeflre 3
Eaglesfield t hah»r and Hashburn, S.,
IEPA
54 10/30/90 Swale, R., U.S. EPA Residents Cover Letter with Hell Sampling Results 5
55 11/00/90 Harzyn Inc. U.S. EPA Technical Heiorandui: Wetlands Delineation 99
56 11/15/90 Uarzyn, Inc. U.S. EPA Hap: RI/FS-Hater Table Contour Hap (Sept. 20- 10
, -1990)
57 12/00/90 Narzyn Inc. U.S. EPA Technical Neiorandui: Hydrogeoloqical 160
Investigation, Phase 1
58 12/00/90 Harzyn Inc. U.S. EPA Technical Heiorandui: Preliminary Baseline 32
Risk Assessment
59 12/0. j Harzyn Inc. U.S. EPA Technical Heiorandui: Source ..aracterization 132
60 12/00/90 Harzyn Inc. U.S. EPA Technical Memorandum: Surface Hater/Sediment 47
Evaluation
61 12/18/90 Harzyn, Inc. U.S. EPA Rap: RI/FS-Surface Hater t Sediment Sample L- 10
ocation Hap
62 12/18/90 Harzyn, Inc. U.S. EPA Hap: Rl/FS-Hater Table Contour Nap IHov. 5, - 10
1990)
63 01/16/91 Bosse, H., Versar, U.S. EPA QftPP: Oversight Acceptance of Collocated 140
Inc. Samples
-------
DOCI
AUTHOR
RECIPIENT
64 02/00/91 Harzyn Inc.
U.S. EPA
65 02/00/91 Hidun, J., Harzyn Swale, R., U.S. EPA
Inc.
66 02/01/91 Harzyn, Inc. Swale, R., U.S. EPA
67 02/01/91 Harzyn, Inc. Swale, R., U.S. EPA
6B 02/04/91 Vagt, P., Harzyn, Swale. R., U.S. EPA
Inc
69 03/00/91 U.S. EPA
70 03/14/91
71 04/03/91
Anderson, 0., City Bacon, J.H., HcHenry
of Hoodstock County Dept. of
Health
72 04/15/91 Bosse, H., Versar Swale, R., U.S. EPA
73 04/18/91
74 04/22/91
75 04/23/91
76 05/10/91
77 06/18/91
78 07/00/91
79 07/02/91
80 08/06/91
81 06/08/91
82 10/00/91
Haher, K., and
Ellis, N.
Vaqt, P., Harzyn,
Inc
Vagt, P., Harzyn,
Inc
Niedergang, N., U.S.
L...
Hud.., D., U.S. LU.
Harzyn Inc.
Nelson, R., U.S. DOI
Swale, R., U.S. EPA
Harzyn, Inc.
Bollo, N., U.S. EPA
U.S. EPA
Swale, R., U.S. EPA
Technical Retorandui: 'Hydrogeological
investigation, Phase 1
Technical Heiorandut: Surface Hater/Sediient
Evaluation
Fax Ccver with Field Boring Logs (1/91)
Fax Cover Hith Field Boring Logs (1/91)
Broundwater Saipling ParaiEters (Phase I:
Round 2; Phase II: Round 1)
Fact Sheet: '*ooostji.k Municipal Landfill
Superfund Site1)
Invitation to !nful national fleet'"? Regarding
the Rl
Statistical Suuary of Sediient Background
Data for RI/FS
(ransiittal Letter with List of Solid Haste
Disposal Sites in Northeastern Illinois
Respondents' Reply to U.S. EPA's Response to
Notice of Dispute
Phase I: Round 2; Phase II: Round 1 Saipling
Results dith Hap t Laboratory Qualifiers
Swale, R., U.S. EPA Correction for Data of 4/3/91
Haher, I., Croier,
Eay.esfield I Haher
Swale, R., U.S. EPA
U.S. EPA
Swale, R., U.S. EPA
Vagt, P., Harzyn
Inc.
U.S. EPA
Naner, K., Cro«r,
Eaglesfield 4 Haher
Final Decision and Resolution of Dispute
U.S. Ul's Conents on the D, .,t FS
QAPP Addendui Kith Attachients
U.S. DOl's Conents on-the Rl Report
U.S. EPA's Couents on the Draft Rl Report
Inorganic and Organic Analysis Data Sheets
Response to Letter of October 4, 1991
H8
50
5
3
2
11
25
3
28
I
40
52
3
-------
DOCI DA it AUTHOR nECIPIENT TlTLE/iiBCRIPTI&N FA5ES
83 10/04/91 Naher, K.. Croier, Bollo, N., U.S. EPA Lett-r Discussing Status of RI/FS and the AOC 5
Eaglesfield I Haher Respondents' (PRPs) Performance
84 02/12/92 Bolen, B., U.S. EPA Vagt, P., Warzyn U.S. tPA's Comments on the 2nd Draft RI 10
Engineering Inc. Report
85 05/05/92 Bolen, M., U.S. EPA Nidian, Karjyn Inc. U.S. EPA's Review and Couents on the Karen 2
1992 RI Report/Ecological Assessment
86 05/15/92 Vagt, P., Warzyn Bolen, B., U.S. EPA Request for Clarification on U.S. EPA 2
Inc. Comments Dated Hay 5, 1992
87 05/20/92 Vagt, P., Warzyn Bolen. «., U.S. EPA lEPA's Comments on the Baseline Risk 31
Inc. Assessment, Final RI Report and Warzyn's
Response to lEPA'stComments
83 05/21/92 IDPH t ATSDR U.S. EPA Interim Preliminary Health Assessment 18
89 06/00/92 Varzyn Inc. Woodstock PRP Group Final Remedial Investigation Report, Vol. t 301
Steering Committee
90 06/00/92 Harzyn Inc. Woodstock PRP Group Final Remedial Investigation Report, Vol. II 798
Steering Committee
91 .06/04/92 Kidman, J., Warzyn Bolen, N., U.S. EPA Response to U.S. EPA's Comments on the RI 6
Inc. Report Dated Nay 20, 1972 re:
Arsenic/Aluminum Methods
92 06/11/92 Vagt, P., Uarzyn Bolen, «., U.S. EPA Response to Final U.S. EPA's Comments re: RI 1
Inc. Report
93 06/12/92 Widman, J.. Uarzyn Bolen. M., U.S. EPA Response to U.S. EPA's Comments on the Final 2
Inc. Draft RI Report Dated Hay 20, 1992
94 07/16/92 Bolen. H., U.S. EPA Hidman, J.. Warryn U.S. EPA's Response to 7/10/92 FS Schedule 6
Inc.
95 07/31/Y2 Va-' P.. Waayn Bolen. H., U.S. EPA ScheC.le for the FS s
Inc.
76 08/04/92 Bolen, K., U.S. EPA Falco. C., IEPA Request for lEPA's Revie* of the Alternatives 2
Array
»7 09/09/92 Bolen, M., U.S. EPA Vaqt. P., Warzyn Letter re: U.S. EPA's Comments on the Draft 3
Inc. Alternatives Array
98 10/00/92 U.S. EPA Fact Sheet: 'Remediil Investigation Complete* 6
99 10/30/92 Naher, «., Cromer. Bollo, M... U.S. EPA Letter re: RPN's Directions to Remove 7
Eaglesfield I flaher Portions of lext Discussing Institutional
Controls in the FS
-------
ooci JA:-: AUTHOR RECIPIENT
JO? 12/08/92 Bolen, «.. U.S. EPft Vagt, P., Narzyn letter re: U.3. EPA's'Second Disapproval 10
Inc. «oti:e for the Draft FS
Ijfl 12/14/92 Vaqt, P., Harzyn Bolen, «., U.S. EPA Request for Meeting to Discuss U.S. EPfl's 1
Inc. 12/9'92 Contents on the First Draft FS Report
Ijtf 12/22/92 Vigt, P., Karzyn Bolen, «., U.S. EPA Letter re: Submitting Second Draft of FS in 1
Inc. Accordance With the Schedule
H53 02/24/93 Falco, C., IEPA Bolen, «., U.S. EPA IEPA s Conents on the ARAR's and the FS 4
J04 03/04/93 Bollo, N., U.S. EPA Haher, 1C., Crowr, Letter re: Reasons For Believing that HCLs 3
Eaglesfield i Naher Are Not AfiAfU
»5 03/15/93 Bolen, »., U.S. EPA Vagt, P., Marzyn Letter re: Thind Disapproval Notice for the i
IRC. FS Report
106 03/17/93 Bolen, «., U.S. EPA Vagt, P., Harzyn Letter re: Thiru Dis?-proval Notice for the 1
Inc. FS Report, Follo«-up to 3/15/93 Letter
^7 03/22/93 Vagt, P., Harryn Bolen, «., U.S. EPA Request for Clarification on U.S. EPA 4
Gottents Dated 3/15/93 re: the Draft FS
Report
108 04/00/93 U.S. EPA Feasibility Study 0
109 04/00/93 Bolen, «., U.S. EPA U.S. EPA Proposed Plan 0
-------
U.S. EPA GUIDANCE ADDENDUM TO THE ADMINISTRATIVE RECORD
WOODSTOCK MUNICIPAL LANDFILL
WOODSTOCK, ILLINOIS
(These guidance documents are available for review at
U.S. EPA, Region V)
04/07/93
DOCI DATE AUTHOR
RECIPIENT
TITLE/DESCRIPTION
PAGES
== = = =
1 10/02/65 Porter, J.M., OSHER U.S. EPA
2 10/01/86 OERR/OSHER
3 12/01/87 OERR/OWE
4 08/08/88 OERR
5 10/01/88 OSHER/OERR
& 02/00/91 OERR
7 07/00/91 U.S. EPA
8 07/00/91 U.S. EPA
U.S. EPA
U.S. EPft
U.S. EPA
U.S. EPA
U.S. EPA
U.S. EPA
U.S. EPA
CERCLA Compliance Kith Other Environmental 19
Statutes, Final, 05NER 19234 0-2
Superfund Public Health Evaluation Manual, 500
Final, GSHER 19285 4-1
i
A Compendium of Superfund Field Operations 550
Methods, Final, JSHER "355 0-14
CERCLA Compliance Kith Other Laws Manual, 245
Draft, OSNER 19234 1-01
Guidance for Conducting Remedial 390
Investigations and Feasibility Studies Under '
CERCLA, Final, OSNER 19355 3-01 .
Conducting Remedial Investigations/Feasibili- 301
ty Studies for CERCLA Municipal Landfill
Sites, OSHER 19355.3-11
Guidance on Oversite of Potentially 124
Responsible Party Remedial Investigations and
Feasibility Studies, Vol. 1, Final, OSHER
19835.1 (d)
Guidance on Oversite of Potentially 193
Responsible Party Remedial Investigations and
Feasibili^ Studies, Final, Vc.. 2, OSHER
19835.1 (cl
-------
U.S. EPA ADMINISTRATIVE RECORD
WOODSTOCK MUNICIPAL LANDFILL
WOODSTOCK, ILLINOIS
UPDATE #1
06 3O/93
DOCI DATE AUTHOR
RECIPIENT
ilTLE/DESCRIPTION
PAGES
1 10/09/92 Bolen, N., U.S. EPA Vagt, P., Narzyn
Inc.
Letter re: U.S. EPA's Coiients on the Draft
FS
2 00/00/93 Citizens
3 04/07/93 U.S. EPA
U.S. EPA
Public
4 04/12/93 Bolen, «., U.S. EPA Vagt, P., Narzyn
Inc.
Citizens' Signatures Requesting a 30 Day 2
Extension to the Public Couent Period
Public Notice: Announcement of the Public i
Couent Period re: the Reaedial Alternatives,
Nhich E«4s Hay 6, 1793
Letter re: U.S. EPA's Receipt of the Draft FS 1
5 05/12/93 U.S. EPA
6 OS/26/93 U.S. EPA
7 05/26/93 U.S. EPA
Public
Public
Public
6 06/04/93 Clifton, T., City of Bolen, N., U.S. EPA
Hoodslock
9 06/04/93 Woodstock Municipal U.S. EPA
Landfill Steering
CoMittee
Public Notice: Public Couent Period Extended 1
Until June S, 1993
Hews Release: 'EPA To Hold Workshops on 1
Woodstock Superfund Site June 2'
Public Notice: U.S. EPA To Hold Workshops on 1
the Hoodstock Superfund Site on June 2, 1993.
City of Woodstock's Public Couent to the 7
Proposed Plan
Public Coiients on the Proposed Plan (Certain 206
Appendices Oaitted, See List of Appendices)
10 06/17/93 Lmon, 0., U.S. EPA Conqill, D., U.S.
EPA
Field Trip Report
-------
U.S. EPA GUIDANCE ADDENDUM TO THE ADMINISTRATIVE RECORD
WOODSTOCK MUNICIPAL LANDFILL
WOODSTOCK, ILLINOIS
UPDATE *1
(These guidance documents are available at U.S. EPA, Region V)
06/3O/93
DOCI DATE AUTHOR RECIPIENT TITLE/DESCRIPTION PASES
1 08/00/90 U.S. EPA U.S. EPA CERCLA Site Discharges to POTUs. 226
EPA/540/6-90/005
-------
U.S. EPA ADMINISTRATIVE RECORD
WOODSTOCK MUNICIPAL LANDFILL
WOODSTOCK. ILLINOIS
UPDATE *2
07/08/93
DOCI DATE AUTHOR RECIPIENT TITiE-JESCRi'TiGN Pft6E5
1 06/30/93 Adukus. V.. U.S. Recipients peco'i of Decision 202
EPA
-------
U.S. ENVIRONMENTAL PROTECTION AGENCY
REMEDIAL ACTION
ADMINISTRATIVE RECORD
FOR
WOODSTOCK MUNICIPAL LANDFILL SITE
WOODSTOCK, ILLINOIS
UPDATE #3
MARCH 18, 1998
NO. DATE
1 04/00/93
2 04/28/93
AUTHOR
Warzyn Inc.
U.S. EPA
3 06/00/93
06/04/93
08/. /93
PRC
.Environmental
Management,
Inc.
Vagt, P.,
Warzyn Inc.
Jade, M..
IEPA
03/00/95
05/01/95
Conestoga-
Rovers &
Associates
Mishra, M.,
PRC
Environmental
Management,
Inc .
RECIPIENT
U.S. EPA
U.S. EPA
Bolen, W.,
U.S. EPA
U.S. EPA
U.S. EPA
O'Grady, J.
U.S. EPA
TITLE/DESCRIPTION
Feasibility Study for
the Woodstock Municipal
T-3.ndfill Site
Transcript of the
April 28, 1993 Public
Meeting re: the Wood-
stock Municipal
Landfill Site
Report: Analysis
Alternatives 4 & 7
from the April 1993
Feasibility Study for
the Woodstock Muni-
cipal Landfill Site
Letter Forwarding
Attached June 4, 1993
Affidavit of Peter J.
Vagt re: the Woodstock
Municipal Landfill Site
IEPA's Decl-.-'ation for
the Record of Decision
for the Woodstock Muni-
cipal Landfill Site w/
Attached Cover Letter
Predesign Work Plan
for the Woodstock
Municipal Landfill
Site
Letter Forwarding
Attached Field Over-
'sight Summary Wo. 1 .-
Remedial Design Field •
Oversight for the
Woodstock Municipal
Landfill Site
146
78
107
47
-------
DATE
09/01/95
AUTHOR
Ratliff, G.,
I EPA
RECIPIENT
O'Grady, J.
U.S. EPA
Woodstock Municipal Landfill AR
UpdaLe #3
Page 2
TITLE/DESCRIPTION
FAX Transmission
Forwarding Attached
Information re: TitJe
35 IAC Part 811.314
PAGES
10/21/95
Isbell, J.,
City of
Woodstock
O'Grady, J.
U.S. EPA
Letter re: Alternatives
for Future Use of the
Woodstock Landfill
Upon Completion of
the Remedial Action
10
12/29/95
Mishra, M.,
PRC
Environmental
Management,
Inc.
O'Grady, J.
U.S. EPA
Letter Forwarding
Attached Field Over-
sight Summary No. 2:
Remedial Design Field
Oversight for the
Woodstock Municipal
Landfill Site
154
11
02/19/96
Wanner, S . ,
Conestoga-
Rovers &
Associates
O'Grady, J.
U.S. EPA
Letter re: Woodstock
PRP Group's Request to
Have the Groundwater
Analytical Parameter
List Reduced for the
March 1996 Quarterly
Monitoring Event
20
12
03/01/96
13
03/07/96
O'Grady, J.,
U.S. EPA
Pochron, W.,
Conestoga-
Rovers &
Associates
Wanner, S. ,
Conestoga-
Rovers &
Associates
O'Grady, J.
U.S. EPA
Letter re: U.S. EPA's
Reply to Woodstock PRP
Group's Request to Have
the Groundwater Parameter
List P.educed for the
Marc . 1996 Quarterly
Monitoring Event
Letter re: Second
Quarterly Sampling
Event for the Woodstock
Municipal Landfill
Site
14
03/11/96
Mishra, M.,
PRC
Environmental
Management,
Inc.
O'Grady, J.
U.S. EPA
Letter re: PRC's
Review of Analytical
Data for Investigative
Split Samples Collected
in October 1995 for the
Woodstock Municipal
Landfill Site
-------
Woodstock Municipal Landlill AK
Update #3
Page 3
15
DATE
03/13/^6
ADTHOR
Ratliff, G.
IEPA
16
03/14/96
Ratliff, G.
IEPA
RECIPIENT
O'Grady J.
U.S. EPA
O'Grady, J.
U.S. EPA
TITLE/DESCRIPTION
FAX Transmission
Forwarding Attached
Information re: Title
35 IAC Part 807.305
Jover Requirements
FAX Transmission
Forwarding Attached
Information re: Title
35 IAC Pare 814. SO J.
and Part 814.502
Concerning the Two
Year Windows for
80? Landfills
PAGES
03/25/96
O'Grady, J.
U.S. EPA
Ratliff,
IEPA
FAX Transmission re:
Questions on Part 807
vs. Part 811.314 of
Title 35 Illinois
Administrative Code
as it applies to the
Woodstock Municipal
Landfill Site and
Tri-County Elgin
Site
03•25/96
O'Grady, J.
U.S. EPA
Wanner, S . ,
Conestcga-
Rovers '
Associates
Letter re: U.S. EP^'s
Comments on the January
1996 .' sitive Environ-
mental Study .Report,
App dix I of the
Predesign Investigation
Report for the Wood-
stock Municipal Landfill
Site
03 '26/96
O'Grady, J.
U.S. EPA
Wanner, S;,
Conestoga-
Rovers &
Associates
Letter re: a Waste
Transfer Station on the
Woodstock Municipal
Landfill Site w/Attach-
ment
Ratliff,
IEPA
O'Grady. J
U.S. EPA
FAX Transmission
Forwarding Attached
Information re:
Relevancy of Title
35 IAC Part 811 with
the Applicability of
Part 807
-------
DATE
21 04/00/96
AUTHOR
Conestoga-
Rovers &
Associates
22 04/00/96
Conestoga -
Rovers &
Associates
23 04/01/96
Ratliff, G.
IEPA
24
04/05/96
25
.722/96
26
06/07/96
27
06/17/96
Mishra, M.,
PRC
Environmental
Management,
Inc.
Wanner, S.,
Conestoga-
Rovers &
Associates
Wanner, S.,
Conestoga -
Rovers &
Associates
Wanner, S.,
Conec-oga-
Rovers &
Associates
RECIPIENT
U.S.. EPA
U.S. EPA
O'Grady, J.
U.S. EPA
O'Grady, J.,
U.S. EPA
O'Grady, J. ,
U.S. FPA
O'Grady, J.,
U.S. EPA and
G. Ratliff,
IEPA
O'Grady, J.,
U.S. EPA
Woodstock Municipal Landfill AR
Update #3
Page 4
TITLE/DESCRIPTION PAGES
Final Predesign 137
Investigation Report:
Volume 1 of 2 (Text,
Figures and Tables)
for the Woodstock Muni-
cipal Landfill Site
Final Predesign 498
Investigation Report:
Volume 2 of 2
lAppendices) for the
Woodstock Municipal
Landfill Site
FAX Transmission re: 5
Questions from U.S. EPA
Regarding Use of 35 IAC
811 Standards at a
Landfill Where 35 IAC
807 Appears to be the
Applicable Regulation
Letter Forwarding 26
Attached Field Over-
sight Summary No. 3 :
Interim Monitoring
Field Oversight for
the Woodstock Muni-
cipal Landfill Site
Letter re: CRA1s 23
Responses t- U.S. E.A's
Comments on the Final
Predesign Investigation
Report for the Woodstock
Municipal Landfill Site
Letter re: Monthly 74
Progress Report for
May 1996 for the Wood-
stock Municpal Landfill
Site
Letter re: Woodstock 2
PRP Group's Request to
Modify the Groundwater
Analytical Parameter
List
-------
NO. DATE
28 06/17/96
AUTHOR
O'Grady,
U.S. EPA
RECIPIENT
Wanner, S.,
Conestoga-
Rut/er=> &
Associates
Woodstock; Municipal Landfill AR
Update <*3
Page 5
TITLE/DSSCRIPTION
Letter re: U.S. EPA's
Response to Woodstock
PRP Group's Request to
Modify the Groundwater
Analytical Parameter
List
PAGES
29 06/20/96
Isbell, J.,
City of
Woodstock
O'Grady, J.
U.S. EPA
City of Woodstock's
Request for Proposals
re: Future Use for
Waste Transfer Station
20
30 07/09/96
Wanner, S . ,
Conestoga-
Rovers &
Associates
0'Grady, J.
U.S. EPA
Letter re: Monthly
Progress Report for
June 1996 for the
Woodstock Municipal
Landfill Site
23
31 07/12/96
Mishra, M.,
PRC
Environmental
Management,
Inc.
O'Grady, J.
U.S. EPA
Letter Forwarding
Attached Field Over-
sight Summary No. 4:
Interim Monitoring
Field Oversight for
the Woodstock Municipal
Landfill Site
22
32 07/29/96
Mishra, M.,
PRC
Environmental
Management,
33 08/08/96
Wanner, S.,
Conestoga-
Rovers &
Associates
O'Grady, J.
U.S. EPA
O'Grady, J.,
U.S. EPA and
G. Ratliff,
IEPA
Letter re: PRC's
Review of Analytical
Data for Investigative
Split Samples Collected
in Mf ~h 1996 for the
Woodst •!< Municipal
Landfill £_te
Letter re: Monthly
Progress Report for
July 1996 for the
Woodstock Municipal
Landfill Site
22
34 08/23/96
Wanner, S . ,
Conestoga-
Rovers &
Associates
O'Grady,
U.S. EPA
J.
Letter re: September
1996 Interim Monitoring
Program Event for the
Woodstock Municipal
Landfill Site
-------
HO. DATE
35 09/26/96
36
10/18/96
37
11/08/96
38
11/21/96
AUTHOR
Mishra, M.,
PRC
Environmental
Management,
Inc.
Wanner, S.,
Conestoga-
Rovers &
Associates
O'Grady, J.
U.S. EPA •
O'Grady, J.
U.S. EPA
RECIPIENT
O'Grady, J.,
U.S. EPA
O'Grady, J.,
U.S. EPA
Wanner, S.,
Conestoga-
Rovers &
Associates
Frehner, R.,
Conestoga-
Rovers &
Associates
Woodstock Municipal Landfill AR
Update #3
Page 6
TITLE/DESCRIPTION
Letter Forwarding
Attached Field Over-
sight Summary; Interim
Monitoring Field
Oversight and Split
Sampling Activities
for the Woodstock Muni-
cipal Landfill Site
Letter re: Regular
Monitoring Events at
the Woodstock Muni-
cipal Landfill Site
Letter re: Regular
Monitoring Events at
the Woodstock Muni-
cipal Landfill Site
Letter re: the Remedial
Design/Remedial Action
Work Plan for the Wood-
stock Municipal Landfilj
Site
PAGES
29
88
39
40
11/26/96
12/02 'S
41
12/20/96
Wanner, S.,
Conestoga-
Rovers &
Associates
O idy, J.
U.S. L?A
Wanner S. and
W. Pochron;
Conestoga-
Rovers &
Associates
O'Grady,
U.S. EPA
J.
Frehner, R.,
Conestoga-
Rovers &
Associates
O'Grady, J.,
U.S. EPA and
G. Ratliff,
I EPA
November 1996 Wetlands 40
Environmental Evaluation
Report for the Woodstock
Municipal Landfill Site
Letter e: the Draft 4
Petition _or an Explana-
tion of Significant
Difference to Delay the
Implementation of the
Pump and Treat System
at the Woodstock Muni-
cipal Landfill Site
Memorandum re: Fourth 91
Quarterly Monitoring
Event Results w/Attached
(1) Summary of Analytical
Results for the Third
Quarterly Monitoring
Event and (2) Data
Quality Assessment and
Validation Memoranda
for the Woodstock Muni-
cipal Landfill Site
-------
NO. DATE
42 12/30/96
43
01/30/97
44
02/07/97
AUTHOR
O'Grady, J.,
U.S. EPA
Mishra, M.,
PRC
Environmental
Management,
Inc.
Wanner, S.,
Conestoga-
Rovers &
Associates
Wobdstock Municipal Landfill AR
Update #3
Page 7
I.ECIPIENT TITLE/DESCRIPTION PAGES
Frehner, R., Letter re: U.S. EPA's 4
Conestoga- Comments on the October
Rovers & 1996 Draft Petition
Associates for an Explanation of
Significant Difference
for the Woodstock
Municipal Landfill Site
O'Grady, J., Letter re: PRC's 2
U.S. EPA Review of Analytical
Data for Split" Samples
Collected in September
1996 for the Woodstock
Municipal Landfill Site
O'Grady, J., Letter re: Monthly 7
U.S. EPA Progress Report for
January 1997 w/Attached
City of Woodstock Letter
Concerning Rezoning of
the Woodstock Landfill
Site
45
03/05/97
O'Grady, J.
U.S. EPA
Frehner, R.
Conestoga-
Rovers &
Associates
Letter re: the Remedial
Design/Remedial Action
Work Plan for the Wood-
stock Municipal Landfill
Site
46
03/07/97
Pochron, W.
Conestooa -
Rovers &
Associates
O'Grady, J.
U.S. EPA
Letter re: April 1997
Semi-Annual ^-roundwater
Sampling Event for th<.
Woodstock Municipal
Landfill Site
47
03/07/97
Wanner, S. ,
Conestoga-
Rovers &
Associates
O'Grady, J.,
U.S. EPA and
G. Ratliff,
IEPA
Letter re: Monthly
Progress Report for
February 1997 for the
Woodstock Municipal
Landfill Site
-------
NO. DATE
48 03/10/97
AUTHOR
Mishra, M.,
PRC
Environmental
Management,
Inc.
RECIPIENT
O'Grady, J.,
L . S . EPA
Woo'dstock Municipal Landfill AR
Update #3
Page 8
TITLE/DESCRIPTION
PAGES
Letter re: PRC's
Technical Review Comments
on the February 1997
Petition for an Explana-
tion of Significant
Difference at the Wood-
stock Municipal Landfill
Site
49
03/11/97
50
03/11/97
51
03/18/97
52
03/2
O'Grady, J.,
U.S. EPA
O'Grady, J.,
U.S. EPA
O'Grady, J.,
U.S. EPA
Frehrier, ">..
Conestoga-
Rovers &
Associates
Frehner, R.,
Conestorja-
Rovers &
Associates
Frehner, R.,
Conestoga-
Rovers a
Associates
Frehner, R.,
Conestoga-
Rovers &
Associates
Michra, M..
1 RC
Envi ronmental
Management,
Inc.
Letter re: U.S. EPA's
Comments or the July
1996 Remedial Design/
Remedial Action Work
Plan for the Woodstock
Municipal Landfill Site
Letter re: U.S. EPA's
Comments on the November
1996 Wetlands Environ-
mental Evaluation Report
for the Woodstock Muni-
cipal Landfill Site
Letter re: U.S. EPA's
Comments on the Feb-
ruary 1997 Petition
for an Explanation of
Significant Difference
for the Woodstock
Municipal Landfill Site
Letter re: M- -ch 20,
^997 Meeting Concerning
Work to be Performed at
the Woodstock Municipal
Landfill Site
53
04/00/97
54
04/00/97
Conestoga-
Rovers &
Associates
Conestoga-
Rovers &
Associates
U.S. EPA
U.S. EPA
Petition for an Explan- 82
ation of Significant
Differences for the
Woodstock Municipal
Landfill Site
Wetlands Environmental 46
Evaluation Report for
the Woodstock Municipal
Landfill Site
-------
NO. DATE
55 04/14/97
AUTHOR
Frehner, R.
Conestoga-
Rovers &
Associates
Woddstock Municipal Landfill AR
Update #3
Page 3
RECIPIENT TITLE/DESCRIPTION PAGES
O'Grady, J. , Letter re: Infiltration 37
U.S. EPA Estimates and Cost
Estimate of Various
Capping Scenarios for
the Woodstock Municipal
Landfill Site
56 04/18/97
57
04/21/97
58
04/21/97
59
05/07/97
60
05/14/97
61 07/09/97
Wanner, S . ,
Conestoga-
Rovers &
Associates
O'Grady, J.,
U.S. EPA
O'Grady, J.,
U.S. EPA
Fabinski, L.,
USDHSS/PHS/
ATSDR
PRC
Environmental
Management,
Inc.
Wanner, S.,
Conestoga-
Rovers &
O'Grady, J.
U.S. EPA
Frehner, R.
Conestoga-
Rovers &
Associates
Frehner, R.
Conestoga-
Rovers &
Associates
O'Grady, J.
U.S. EPA
U.S. EPA
O'Grady, J.,
U.S. EPA and
G. Ratliff,
I EPA
Letter re: CRA's
Responses to U.S. EPA's
Comments on the 1,'ovember
1996 Wetlands Environ-
mental Evaluation Report
for the Woodstock Muni-
cipal Landfill Site
Letter re: Infiltration
and Cost Estimates of
Various Capping Scenarios
for the Woodstock Muni-
cipal Landfill Site
Letter re: Land Use
Restrictions Requirements
for the Woodstock Muni-
cipal Landfill Site
April 30, 1997 Public
Health Assessment for
the Woodstock Municipal
Landfill Site w/Attached
Cover Letter
Technical Memorandum:
Simulation of Surface
Water Infiltration and
Evaluation of Cap
Construction Costs for
the Woodstock Municipal
Landfill Site
Letter re: Monthly
Progress Report for
June 1997 for the
Woodstock Municipal
Landfill Site
52
89
62 08/01/97
City cf
Woodstock/
AlliedSignal,
Inc.
U.S. EPA
Petition to Amend the
Record of Decision for
the Woodstock Muni-
cipal Landfill Site
604
-------
NO. DATS
63 08/04/97
AUTHOR
Flynn, D.;
Phillips,
Lytle,
Hitchcock,
Elaine &
Huber
RECIPIENT
Alcamo, T.,
U.S. EPA
Woodstock Municipal Landfill AR
Update #3
Page 10
TITLE/DESCRIPTION
Cover Letter Forward-
ing the Petition to
Amend the .Record of
Decision for the
Woodstock Municipal
Landfill Site
PAGES
64 10/27/97
65 11/18/97
Frehner, R.,
Conestoga-
Rovers &
Associates
Mishra, M.,
PRC
Environmental
Management,
Inc.
O'Grady, J.,
U.S. EPA
O'Grady, J.,
U.S. EPA
Letter re: CRA's
Proposed Landfill Cap
for the Woodstock Muni-
cipal Landfill Site
Memorandum re: Cost
Estimate for Cap at
the Woodstock Muni-
cipal Landfill Site
66 12/05/97
67 12/19/97
68 01/02/98
69 01/12/98
Flynn, D.;
Phillips,
Lytle,
Hitchcock,
Blaine &
Huber, LLP
Flynn, D.;
Phillips,
Lytle,
Hitchcock,
Blaine &
Huber, LLP
Muno, W.,
U.S. EPA
Wanner, S.,
Conestoga-
Rovers &
Associates
O'Grady, J.
U.S. EPA
Muno, W.,
U.S. EPA
O'Grady, J. ,
U.S. EPA and
G. Ratliff,
I EPA
Ratliff, G.,
I EPA
Letter re: the Petition
to Amend the Record of
Decision for the Wood-
stock Municipal Landfill
Site
Letter re: the Cap ARAR 3
Issue at the Woodstock
Municipal Landfill Site
w/Attached December 11,
1997 Circuit Court
Summ.? / JudgT ^nt in
City of Woodstock vs.
Illi jis Environmental
Protection Agency
Letter re: October 1997 40
Semiannual Monitoring
Event at the Woodstock
Municipal Landfill Site
Letter re: U.S. EPA's 1
Request for Illinois
ARARs for the Proposed
Plan and Record of Decision
Amendment for the Wood-
stock Municipal Landfill
Site
-------
Woodstock Municipal Landfill AR
Update #3
Page 11
NO. DATE
70 01/16/98
AUTHOR
Flynn, D.;
Phillips,
Lytle,
Hitchcock,
Elaine &
Huber, LLP
RECIPIENT
O'Grady, J.,
U.S. EPA
TITLE/DESCRIPTION PAGES
Letter re: August 1, 6
1997 Record of Decision
Amendment Petition for
the Woodstock Municipal
Landfill Site
71 02/00/98
U.S. EPA
Public
72 02/17/98
Furey, E.,
U.S. .EPA
Flynn, D.;
Phillips,
Lytle,
Hitchcock,
Blaine &
Huber, LLP
Fact Sheet and Proposed
Plan: U.S. EPA Recommends
Revisions to Cleanup Plan
for the Woodstock Muni-
cipal Landfill Site
Letter re: U.S. EPA's
Intention to Amend the
Record of Decision for
the Woodstock Municipal
Landfill Site w/Attach-
ment
19
73 02/19/98
74 02/23/98
Barov, B.,
State of
Illinois/
Office of
the Attorney
General
Wright, J.;
McBride,
Baker &
Coles
Furey, E.,
U.S. EPA
Furey, E.,
U.S. EPA
Letter Forwarding
Attached December 11,
1997 Circuit Court Order
re: City of Moodstock vs.
Illinois Environmental
Protection Agency
Letter re: Identifica-
tion of ARARs Pertaining
to the Landfill Cap at
the Woodstock Municipal
.aafill Site w/Attach-
75 02/27/98
Furey, E.,
U.S. EPA
Wright, J. ,-
McBride,
Baker &
Coles
Letter re: Identifica-
tion of ARARs for the
Landfill Cap Component
of.the Woodstock Muni-
cipal Landfill Remedy
76 07/00/89
U.S. EPA/
OSWER
GUIDANCE ADDENDUM
U.S. EPA
Technical Guidance
Document: Final Covers
on Hazardous Waste
Landfills and Surface
Impoundments (EPA 530-
SW-89-047)
49
-------
NO. DATE
77 03/00/90
78
08/17/90
AUTHOR
U.S. EPA/
ERL/ORD
Falco, C.
IEPA
RECIPIENT
U.S. EPA
Bolen, B.
U.S. EPA
79
05/00/91
80
10/00/92
Eastern
Research
Group, Inc.
U.S. EPA/
OSWER/ORD
U.S. EPA
U.S. EPA
81
09/00/93
U.S. EPA/
ORD
U.S. EPA
Woodstock Municipal Landfill AS
Update #3
Page 12
TITLE/DESCRIPTION
Report: Basics of Pump- 66
and-Treat Ground-Water
Remediation Technology
(EPA/600/8-90/003)
Illinois Pollution 188
Control Board's Opinion
on 35 IAC, Subtitle G,
Parts 810-815: Develop-
ment, Operating and
Reporting Requirements
for Non-Hazardous Waste
Landfills w/Attached
Cover Letter
Seminar Publication: 4
Design and Construction
of RCRA/CERCLA Final
Covers (EPA/625/4-91/
025)
Technical Guidance 0
Document: Construction
Quality Management for
Remedial Action and
Remedial Design Waste
Containment Systems
(EPA/540/R-92/073)
[THIS DOCUMENT HAS NOT
BEEN COPIED FOR PHYSICAL
INCLUSION rTO THE AR:
DOCUMENT MAY BE VIEWED
AT i'.S. EPA REGION _,
Technical Guidance 0
Document: Quality
Assurance and Quality
Control for Waste
Containment Facilities
(EPA/600/R-93/182)
[THIS DOCUMENT HAS NOT
BEEN COPIED FOR PHYSICAL
INCLUSION INTO THE AR:
DOCUMENT MAY BE VIEWED
•AT U.S. EPA REGION 5]
-------
SSL. DATE
82 05/00/94
AUTHOR
U.S. EPA/
ORD
RECIPIENT
U.S. EPA
83
05/00/94
U.S. EPA/
OSWER
U.S. EPA
84
10/17/95
Feldman, P.
U.S. EPA/
OERR
U.S. EPA
85
03/00/96
86
09/13/96
U.S. DOI/
Bureau of
Reclamation
and U.S. EPA/
NRMRL
Wiedemeier,
T. , et al.
U.S. EPA
Woodstock Municipal Landfill AR
Update #3
Page 13
TITLE/DESCRIPTION PAGES
Seminars: Construction 0
Quality Assurance/
Construction Quality
Control for Waste
Containment Facilities:
Hydraulic Evaluation
of Landfill Performance
(HELP) Model (EPA/625/
K-94/001) [THIS DOCUMENT
HAS NOT BEEN COPIED FOR
PHYSICAL INCLUSION INTO
THE AR: DOCUMENT MAY BE
VIEWED AT U.S. EPA
REGION 5]
Superfund Publication: 47
Considering Wetlands at
CERCLA Sites (EPA 540/
R-94/019; Publication
9280.0-03; PB94-963242)
Paper: EPA's Perspective 4
on Remediating Contamin-
ated Ground Water Using
Natural Attenuation
(Conference Proceedings:
Intrinsic Bioremediation:
Strategies for Effective
Analysis Monitoring and
Impl ^ntation; October
16-17 1995)
Report: Freeze-Thav/ 128
Cycling and Cold Temper-
ature Effects on Geo-
membrane Sheets and
Seams [FINAL] (R-96-03)
Paper: Overview of the 25
Technical Protocol for
Natural Attenuation of
Chlorinated Aliphatic
Hydrocarbons in Ground
Water Under Development
for the U.S. Air Force
Center for Environmental
Excellence (Symposium on
Natural Attenuation of
Chlorinated Organics:
September 11-13, 1996)
-------
NO. DATE
87 10/00/96
AUTHOR
U.S. EPA/
OSWER
RECIPIENT
U.S. EPA
88
01/00/97
U.S. EPA
89
11/00/97
U.S. EPA/
OSWER
U.S. EPA
Woodstock Municipal Landfill AR
Update #3
Page 14
TITLE/DESCRIPTION PAGES
Final Guidance: 86
Presumptive Response
Strategy and Ex-Situ
Treatment Techno!ogies
for Contaminated Ground
Mater at CERCLA Sites
(EPA 540-R-.96-023; .
OSWER Directive 9283.1-
12; PB 963508)
OSWER Directive Class- 3
ification Numbering
System (DOCUMENTS
INDICATED BY ** ARE
INCORPORATED BY REFERENCE
INTO THE ADMINISTRATIVE
RECORD)
Guidance Document: Use 40
of Monitored Natural
Attenuation at Superfund,
RCRA Corrective Action,
and Underground Storage
rank Sites [DRAFT INTERIM
FINAL] (OSWER Directive
9200.4-17)
-------
U.S. ENVIRONMENTAL PROTECTION AGENCY
REMEDIAL ACTION
ADMINISTRATIVE RECORD
FCR
WOODSTOCK MUNICIPAL LANDFILL SITE
WOODSTOCK, ILLINOIS
UPDAT2 #4
JULY 7, 1998
NO. DATS
1 00/00/00
AUTHOR
Falco, C.,
IEPA
2 08/07/92
3 09/02/92
Falco, C.
IEPA
Falco, C.
IEPA
4 09/14/92
5 10/09/92
6 10/3.,92
7 11/16/92
8 11/23/92
Falco, C.
IEPA
Bolen, W.
U.S. EPA
Vagt, P.,
Warzyn
Engineering,
Inc.
Falco, C:,
IEPA
Falco, C.,
IEPA
RECIPIENT
Bolen, W.
U.S. EPA
TITLE/DESCRIPTION
PAGES
Bolen, W.,
U.S. EPA
Bolen, W.,
U.S. EPA
Bolen, W.,
U.S. EPA
Vagt, P.
Warzyn
Engineering,
Inc.
Bolen, '1. ,
U.S. EPA
Bolen, W.,
U.S. EPA
Bolen, W.,
U.S. EPA
Letter Forwarding
Attached Illinois Pollu-
tion Control Board's .
Opinion re: 35 IAC,
subtitle G, Parts 810-
815 (Landfill Regulations)
Letter re: Calculation
Errors in the Final
Remedial Investigation
Report for the Woodstock
Municipal Landfill Site
Letter re: lEPA's
Comments on the August
i992 Alternative Array
Document for the Wood-
stock Municipal Landfill
Site
Letter re: Illinois ARARs
for the Woodstock Muni-
cipal Landfill Site
Letter re: U.S. EPA's
Comments on the September
1992 Draft Feasibility
Study for the Woodstock
Municipal Lp-'dfill Site
Lette re: Modifications
to the Draft Feasibility
Study for the Woodstock
Municipal Landfill Site
Letter re: IEPA Comments
on the Third Submittal
of the Feasibility Study
for the Woodstock Muni-
cipal Landfill Site
Letter re: lEPA's
Additional Comments on
the Feasibility Study
for the Woodstock Muni-
cipal Landfill Site
188
-------
Woodstock AR
Update #4
Page 2
NO. DATS
9 12/29/92
AUTHOR
Vagt, P.,
Warzyn
Engineering,
Inc.
RECIPIENT
Bolen, w.,
U.S. EPA
TITLE/DESCRIPTION
PAGES
10 01/25/93 Bolen, W.,
U.S. EPA
Addressees
11
12
01/28/93
02/11/93
13
02/16/93
14
03/23/93
15 03/j '93
16
04/08/93
17 04/12/93
Maher, K.,
Cromer,
Eaglesfield
& Maher
Widman, J.,
Warzyn
Engineering,
Inc.
Falco, C.,
IEPA
Bolen, W.,
U.S. EPA
£ ;o, C .
IEPA
Bolen, W.
U.S. EPA
Bolen, w.
U.S. EPA
Bollo, N.
U.S. E?A
Bolen, . W.
U.S. EPA
Bolen, W.,
U.S. EPA
Addressees
Bolen, W.
U.S. EPA
Addressees
Vagt, P.,
Warzyn
Engineering,
Inc.
Letter re: Warzyn's 3
Response to lEPA's August
3, 1992 Comments on the
Baseline Risk Assessment
for the Final Remedial
Remedial Investigation
Report for Lhe Woodstock
Municipal Landfill Site
Cover Memorandum Forward- 1
ing the Feasibility Study
for the Woodstock Muni-
cipal Landfill Site for
Tlaview
Letter re: Maximum 3
Containment Levels (MCLs)
as ARARs for the Woodstock
Municipal Landfill Site
Letter re: January 1993 2
Monthly Status Report
for the RI/FS at the
Woodstock Municipal Land-
fill Site
Letter re: lEPA's 3
Comments on the .Revised
Feasibility Study for
the Woodstock Municipal
Landfill Site
Cover Memorandum 1
Forwarding the Draft
Proposed Plan for the
Woodstock Municipal Land-
fill f-te for Review
Lett re: j.EPA's 2
Comments on the Draft
Proposed Plan for the
Woodstock Municipal Land-
fill Site
Cover Memorandum Forward- l
ing the Final Proposed
Plan for the Woodstock
Municipal Landfill Site
for Review
Letter re-. (1) Receipt l
of the Final Draft Feasi-
bility Study; (2) Dis-
charge of Groundwater to
the POTW; and (3) Cleanup
of Contaminated Sediments
Prior to Capping at the
Woodstock Municipal Land-
fill Site
-------
NO.
18 06/17/93
AUTHOR
Falco, C.,
IEPA
19
06/18/96
20
21
07/00/96
07/31/96
22
08/01/96
23
09/09/96
Day, S.,
Conestoga-
Rovers &
Associates
Conestoga-
Rovers &
Associates
Frehner, R.
Conestoga-
Rovers &
Associates
Wanner, S.,
Conestoga-
Rovers &
Associates
O'Grady, J.
U.S. EPA
24
02/10/97
Wanner, S.,
Conestoga-
Rovers &
Associates
25 03/10/97
Mishra, M.,
PRC
Environmental
Management,
Inc.
RECIPIENT
Bolen, W.,
U.S. EPA
O'Grady, J.
U.S. EPA
U.S. EPA
O'Grady, J.
U.S. EPA
O'Grady, J.
U.S. EPA
Frehner, R.
Conestoga-
Rovers U
Associates
O'Grady, J.
U.S. EPA.
O'Grady, J.
U.S. EPA
Woodstock AR
Update #4
Page 3
TITLB/PBSCRIPTION
Letter re: lEPA's 23
Comments on the Draft
Record of Decision for
the Woodstock Municipal
Landfill Site w/ Hand-
written Annotated Copy
of the ROD
Letter Forwarding 8
Attached Revised Pages
for the Quality Assurance
Project Plan for the
Hoodstoc/v Municipal Land-
fill Site
Draft Remedial Design/ 49
.Remedial Action Work Plan
for the Woodstock Muni-
cipal Landfill Site
Letter re: Institutional 14
Controls and Land Use
Restrictions at the
Woodstock Municipal Land-
fill Site w/ Attachments
Letter re: CRA's 23
Responses to U.S. EPA's
June 17, 1996 Comments
on the Predesign Investi-
gation Report for the
Woodstock Municipal Land-
fill Site
Letter re: U.S. EPA's 8
Comments on the Remedial
Design/Remedial Action
Work Plan for the Wood-
stocv Municipal LanC'ill
Site (DRAFT)"
Letter re: CRA's 13
Responses to U.S. EPA's
December 30, 1996 Comments
on the Draft Petition for
an Explanation of Signi-
ficant Difference for the
Woodstock Municipal Land-
fill Site
Letter re: PRC's Tech- 6
nical Review Comments on
the Petition for an
Explanation of Significant
Difference for the Wood-
stock Municipal Landfill
Site
-------
NO. DATS
26 04/00/97
27 04/03/97
28 04/10/97
29 04/21/97
30 07/08/97
31
07/11/97
32
09/04/97
33 10/08/97
ADTHOR
Conestoga -
Roveis &
Associates
Wanner, S.,
Conestoga-
Rovers &
Associates
Wanner, S.,
Conestoga-
Rovers &
Associates
O'Grady,
U.S. EPA
O'Grady, J.
U.S. EPA
Wanner, S.,
Conestoga-
Rovers &
Associates
Flynn, D.,
Phillips,
Lytle,
Hitchcock,
Elaine &
Huber, LLP
Mishra, M.,
Tetra Tech
EM, inc.
RECIPIENT
U.S. £PA
O'Grady, J.,
U.S. EPA
O'Grady,
U.S. EPA
Frehner, R.
Conestoga-
Rovers &
Associates
Frehner, R.
Conestoga-
Rovers &
Associates
O'Grad" J.
U.S. EPA &
G. Ratlif*,
IE?A
O'Grady, J.,
U.S. EPA
O'Grady, J.
U.S. EPA
Woodstock AR
Update #4
Page 4
TITLE/DBSCRIPTION
PAGES
Remedial Design/Remedial 52
Action Work Plan for the
Woodstock Municipal Land-
fill Site
Letter re: CRA's 7
Responses to U.S. EPA's
Comments on the February
1997 Petition for an
Explanation of Significant
Difference for the Wood-
stock Municipal Landfill
Site
Letter re- CRA's 16
Responses to U.C. EPA's
Comments on the RD/RA
Work Plan, Sampling and
Analysis Plan, and Health
and Safety Plan for the
Woodstock Municipal Land-
fill Site
Letter re: Land Use 2
Restrictions Requirements
for the Woodstock Muni-
cipal Landfill Site
Letter re: U.S. EPA's 3
Approval of the RD/RA
Work Plan and Quality
Assurance Project Plan
for the Woodstock Muni-
cipal Landfill Site w/
Attached QAPP Signature
Pages
Memorandum re: April 58
1997 Semiannual MoniLwr-
ing Event a^ the Wood-
stock Municipal Landfill
Site
Preliminary (30%) Design 153
Report for the Woodstock
Municipal Landfill Site
w/ Attached Cover Letter
Letter re: Tetra Tech's
Technical Review Comments
on the Preliminary (30%)
Remedial Design Report
for the Woodstock Muni-
cipal Landfill Site
-------
NO. DATE
34 01/06/98
35
01/07/98
AUTHOR
Frehner, R.
Conestoga-
Rovers Se
Associates
U.S. EPA
RECIPIENT
O'Grady,
U.S.. EPA
J.
File
36
03/04/98
37
04/01/98
Northwest
Court
Reporting
Services,
P.C.
O'Grady, ^
U.S. EPA
U.S. EPA
Frehner, R.
Conestoga-
Rovers &
Associates
38
04/07/98
39
04/14/98
Frehner, R.,
Conestoga-
Rovers s-
Associates
Mayka, J. and
W. Carney,
U.S. EPA
Erne r i c, N.
U.S. EPA
U.S. EPA/
Superfund
RPMs
40
04/20/98
Frehner, R.,
Conestoga-
Rovers &
Associates
O'Grady, J.
U.S. EPA
Woodstock AR
Update #4
Page 5
TITLE/DESCRIPTION PAGES
Letter Forwarding 17
Attached HELP Modeling
Scenarios: (l)Geonet
Drainage Layer and (2)
Fill Drainage Layer
for the Woodstock Muni-
cipal Landfill Site
Hydrologic Evaluation 44
of Landfill Performance
[HELP Model Version 3.03]:
(1-2) EPA/CRA's Design
After One Freezing and
(3-4) EPA/CRA's Design
After 300 Fold Increase
in Permeability
Transcript of March 4, 51
1998 Public Meeting re:
the Woodstock Municipal
Landfill Site
Lecter re: U.S. EPA's 14
Response to (1) City of
Woodstock/AlliedSignal's
August 1997 Petition to
Amend the Record o£
Decision and (2) CRA's
Proposal for a Modified
Cap Design at the
Woodstock Municipal
Landfill Site
Letter re: CRA's 5
Comments on the Proposed
Plan for the ROD Amend-
ment for the Woodstock
.nicipal i andfill Si_e
Memorandum re: Findings 25
and Recommendations of
the Working Group
Reviewing Landfill Cover
Requirements and Decision
Making by Region 5
Superfund Program
Letter re: CRA's Response 1
to U.S. EPA's April 1,
1998 Letter Concerning
the Proposed Plan for the
ROD Amendment for the
Woodstock Municipal Land-
fill Site
-------
NO. DATE
26 04/00/97
27 04/03/97
28 04/10/97
29 ' 04/21/97
30 07/08/97
31
07/11/97
32
09/04/97
33
10/08/97
AUTHOR
Conestoga-
Roveis &
Associates
Wanner; S.,
Conestoga-
Rovers &
Associates
Wanner, S.,
Conestoga-
Rovers &
Associates
O'Grady, J.,
U.S. EPA
O'Grady, J. ,
U.S. EPA
Wanner, S.,
Conestc-ia-
Rovers ft
Associates
Flynn, D.,
Phillips,
Lytle,
Hitchcock,
Blaine &
Huber, LLP
Mishra, M.,
Tetra Tech
EM, Inc.
RBCIP TENT
U.S. £PA
O'Grady, J.
U.S. EPA
O'Grady, J. ,
U.S. EPA
Frehner, R.
Conestoga-
Rovers &
Associates
Frehner, R.
Conestoga-
Rovers &
Associates
O'Grady, J.,
U.S. EPA &
G. Ratlif-,
I EPA
O'Grady, J.,
U.S. EPA
O'Grady, J.,
U.S. EPA
Woodstock AR
Update #4
Page 4
TITLE/DESCRIPTION
PAGES
Remedial Design/Remedial 52
Action Work Plan for the
Woodstock Municipal Land-
fill Site
Letter re: CRA's 7
Responses to U.S. EPA's
Comments on the February
1997 Petition for an
Explanation of Significant
Difference for the Wood-
stock Municipal Landfill
Site
Letter re: CRA's 16
Responses to U.S. EPA's
Comments on the RD/RA
Work Plan, Sampling and
Analysis Plan, and Health
and Safety Plan for the
Woodstock Municipal Land-
fill Site
Letter re: Land Use 2
Restrictions Requirements.
for the Woodstock Muni-
cipal Landfill Site
Letter re: U.S. EPA's 3
Approval of the RD/RA
Work Plan and Quality
Assurance Project Plan
for the Woodstock Muni-
cipal Landfill Site w/
Attached QAPP Signature
Pages
Memorandum re: April 58
1997 Semia- -ual Monitor-
ing Event a" the Wood-
stock Municipal Landfill
Site
Preliminary (30%) Design 153
Report for the Woodstock
Municipal Landfill Site
w/ Attached Cover Letter
Letter re: Tetra Tech's
Technical Review Comments
on the Preliminary (30%)
Remedial Design Report
for the Woodstock Muni-
cipal Landfill Site
-------
NO. DATS
41 05/11/98
42
05/20/98
43
06/00/98
44
45
46
07/01/98
07/07/98
07/07/98
AUTHOR
Mishra, M.,
Tetra Tech
EM, Inc.
Ratliff, G.
I EPA
U.S. EPA
Wanner, S.,
Conestoga -
Rovers &
Associates
Mishra, M.,
PRC
Environmental
Management,
Bolen, W.,
U.S. EPA
RECIPIENT
O'Grady. J.
U.S. EPA
O'Grady, J.
U.S. EPA
File
O'Grady, J.
U.S. EPA &
G. Ratliff,
IEPA
O'Grady, J.
U.S. EPA
U.S. EPA
Woodstock AR
Update #4
Page 6
TITLE/DESCRIPTION PAGES
Letter re: Tetra Tech's 2
Technical Review of the
Slope and Subgrade Com-
paction Recommended by
CRA for the Landfill
Cover at the Woodstock
Municipal Landfill Site
Letter re: lEPA's Con- 2
currence with the Proposed
Plan for the ROD Amend-
ment for the Woodstock
Municipal Landfill Site
Guidance: OSWER Directive 73
Classification Numbering
System (Documents Indica-
ted by * are Incorporated
by Reference into the
Administrative Record)
Letter re: April 1998 47
Semiannual Monitoring
Event at the Woodstock
Municipal Landfill Site
Letter re: Cost Update 1
to the ROD Amendment for
the Woodstock Municipal
Landfill Site
Affidavit re: ARAR 32
Determination by IEPA
for the Woodstock Muni-
cipal Landfill Site
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