EPA/AMD/R05-98/155
1998

EPA Superfund

Record of Decision Amendment:

WOODSTOCK MUNICIPAL LANDFILL

EPA ID: ILD980605943

OUOl

WOODSTOCK, IL
07/15/1998

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EPA 541-R98-155


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

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RECORD OF DECISION AMENDMENT

SELECTED REMEDIAL ALTERNATIVE

DECLARATION

SITE NAME AND LOCATION

Woodstock Municipal Landfill Superfund 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 reguirement 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 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:

•	Excavation and consolidation of contaminated sediments and sludges under the landfill cap;

•	Installation and maintenance of a geosynthetic landfill cap in compliance with the
specifications set forth in this ROD Amendment;

•	Installation and maintenance of a landfill gas venting system that is compatible with the
type of cap specified in this ROD Amendment;

•	Installation and operation of a groundwater extraction, treatment, and discharge system as
a contingent component of the remedy, reguired 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;

•	Development and implementation of a comprehensive monitoring program to ensure the
effectiveness of the remedy;

•	Mitigation of wetland areas where contaminated sediment removal occurs;

•	Mitigation of wetland damage or loss during or after remedial activities are complete;

•	Development and implementation of a surface water and sedimentation control system;

•	Implementation of institutional controls to limit land and groundwater use.

The following remedial actions from the June 30, 1993, ROD remain in fall 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.

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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. Because this remedy may result in hazardous
substances remaining on site 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.

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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 1. The coordinates for the Site are northeast quarter of Section 17,
Township 44 North, Range 7 East (NE 1/4, Se 17, T44N, R7E).

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 drinking water source, regardless of municipal land 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
Site, groundwater contamination has not migrated 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 and open burning
area. Beginning in 1958, the Site was used by the City under a 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
polychlorinated 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

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the landfill in the near future and because the leachate 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.

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 subseguent
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 October
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 reguired 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 reguired: (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: Solid Waste and Special Waste Hauling, Part 811.314; and (2) installation and operation of a
groundwater 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 reguired land use restrictions to ensure that the physical and structural
integrity of the cap and its components were not compromised. According to the information submitted by the
PRPs, the following actions have been taken:

•	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.

•	On January 7, 1997, the City passed Ordinance No. 2 659 which
reclassifies the property which was formerly used as the
City of Woodstock landfill, from a RIS residential district
to a M2 General Manufacturing District.

By letter dated April 27, 1997, the U.S. EPA gueried whether Resolution No. 635 prohibited the construction

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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 an extraction well, performance of an
aguifer pumping 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 aguifer zones at the Site. Groundwater in the upper

unit, however, was found to contain contamination. The contaminant of concern in the upper water-bearing unit
downgradient of the landfill is vinyl chloride. Receptors of groundwater discharge from the upper
water-bearing unit include the Kishwaukee River and the wetlands 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 aadition, 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
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 (ESD) to
delay the design and implementation of the groundwater pump-and-treat system based on data obtained during
the PDI and the guarterly monitoring events. However, the U.S. EPA could not grant the ESD for the
delay of the groundwater pump-and-treat system, without an adeguate 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 see page 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 long-term protection of human health and the environment.

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 reguirements 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 identification of 35 IAC 807 as
the applicable or relevant and appropriate reguirement (ARAR) for the landfill cap; and (2) deletion of the
reguirement for an active pump-and-treat groundwater collection and treatment system. In other words, the PRP
Group renewed its efforts to have the pump-and-treat system deleted as a reguirement 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

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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 reguired the
construction of a cap that met or exceeded the reguirements 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 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 reguired 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 reguirements of Section 113 (k)(2)(B)(I-v) of the CERCLA, as amended
by SARA, have been achieved for the Site by:

•	A Site information repository was established at the Woodstock Public Library to allow local
access to Site-related documents;

•	The Site Administrative Record has been updated to include the Proposed Plan for a ROD
Amendment and other documents relied upon for this ROD Amendment, and has been placed in
the Site information repository;

•	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;

•	The Proposed Plan for a ROD Amendment was released for public comment and placed into the
Administrative Record on February 23, 1998;

•	A thirty (30) day comment period was established and scheduled to end on March 24, 1998;

•	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

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Administrative Record and Site repositories;

•	The U.S. EPA granted a fifteen (15) day extension of the public comment period on March 4,
1998, extending the closing date to April 8, 1998;

•	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;

•	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
reguirements. 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 reguired 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.

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 reguired by the
origional ROD (~$6.2-million, adjusted for 1998 costs and doliars). 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 and consolidation; (E) landfill gas collection system; (F)
well monitoring 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's 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:

•	Groundwater contamination was detected in the upper aguifer 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.

•	Contamination was detected in leachate gas samples and in leachate 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

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affecting the groundwater, surface water and sediments at the Site.

•	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 (VOCs),

semi-volatile organic compounds, (SVOCs), and inorganic compounds.

•	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. Conseguently, 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, concentration 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 guality in the upper
water-bearing unit:

•	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.

•	SVOCs, pesticides and PCBs were not contaminants of concern in groundwater.

•	Six target analyte list (TAL) metals were found to exceed applicable groundwater guality
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 guality criteria.

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.

•	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 aguifer 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 zone 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

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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 cover. The HELP model predicted that surface 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 aguifer 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 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 aguifer 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 determine the thickness of the cover. Boring
logs compiled from 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) 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 guestionable 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 whole.

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

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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) that 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 guantities of water through soil. Considering the HELP model infiltration estimate of 4.4 6
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 (Ig/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 defined 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 concentrations
exceeding the MCL at any of the new monitoring 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.

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 aguifer 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 reguest 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 reguested 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 reguired in the original ROD with potential alternative

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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
Ig/L and at monitoring well MW-8 have ranged from 7 to 12 Ig/L. These vinyl chloride concentrations are
approximately one-third lower than the concentrations observed during the RI (16 to 21 Ig/L at MW-4d and from
20 to 21 Ig/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 may have occurred even during the relatively short
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 reguired 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 Ig/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 will
remain constant throughout the duration of 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:

•	there is no demand for the resource while the natural attenuation remedy is in progress;

•	long-term exposure controls are in effect to prevent exposure to contaminated groundwater and
ensure protectiveness;

•	the potential for further contaminant migration is low; and

the natural attenuation remedy is employed in combination with other remedial 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 concentrations of contaminants downgradient of 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 no 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 reguires that

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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 reguired 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 Wised
upon the following assumptions:

•	there is approximately 4.4 million gallons of contaminated groundwater present in the vinyl
chloride plume;

•	a sustained pumping rate of between 4 and 5 gallons per minute will be achieved during the
remediation; and

•	ten aguifer 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 reguired 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 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 in 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 ug/L in September 1996 and April 1997. In light of the reduction in
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 reguired construction of a landfill cap that included the following parameters:

•	placement of a geosynthetic liner with a bentonite clay layer, with a 1 x 10 -7 cm/s
permeability;

•	three feet of final cover layer;

•	placement of a drainage layer, rooting zone layer and topsoil;

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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 leachate than the U.S.
EPA believed at the time 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 Reguirements. (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
reguired.

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 of 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 laLndfill 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:

•	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);

•	installation of a 40-mil linear low density polyethylene liner;

•	installation of a drainage layer;

•	installation of a geofabric to protect the integrity of the drainage layer;

•	Installation of 24 inches of soil cover above the drainage layer, 6 inches of which must be
topsoil;

•	final grading of the total cover to no less than 2.0% slope.

Summary

The June 30, 1993, ROD reguired 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 accomplished 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 guality 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 reguired 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 reguired 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

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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 durinq the initial 5-year review.

Finally, the landfill cap specified in this ROD Amendment will siqnificantly reduce leachate qeneration,
which should further improve the qroundwater quality. Furthermore, the cap will comply with the landfill cap
ARAR, and will qenerally not be subject to damaqe from freeze/thaw or wet/dry cycles. The landfill cap
specified in this ROD Amendment also requires an efficient drainaqe layer that will virtually eliminate
standinq water from the protective layer, thus eliminatinq infiltration throuqh the barrier layer, thereby
increasinq the operational effectiveness of the landfill cap in limitinq surface water infiltration.

These modifications to the oriqinal 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). Usinq information
about what contaminants are present at the Site, as well as the concentrations, quantities, locations and
ability of the contaminants to miqrate, a BLRA was developed to determine what, if any, human health risks
are posed by the Site.

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 (carcinoqens), risks were estimated as the additional
possibility of developinq cancer due to exposure to the compounds. For the non-cancer causinq

compounds (noncarcinoqens), 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 qreater than 1, adverse
health effects are possible.

The BLRA indicated that the Site, as it now exists, may pose an unacceptable cancer risk of (CR) of 5 x 10 -5
or CR = 5 x 10 -5) to trespassers (children/adolescents playinq on-Site) throuqh exposure to surface soils.
This exposure may occur throuqh inqestion 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 beinq used as a park or recyclinq 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 -4) risk
to these park users. The primarychemicals 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 beryllium. Another potential health risk would 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
qroundwater contaminated with vinyl chloride was consumed over a lonq exposure period by the resident(s)
drinkinq from a contaminated well.

Environmental Risks

The ecoloqical 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 requlatory criteria also poses a
potential risk. No conclusions could be reached as to whether past ecoloqical effects have occurred due to
the presence of other inorqanic contaminants in surface water and sediments at the Site due to the lack of
biota samplinq or bioloqical assays.

It is important to understand that the U.S. EPA has been directed by Conqress to restore qroundwater to its
beneficial uses, whenever practicable. 1 The aquifers underlyinq the Site have been desiqnated by the State
of Illinois as Class I, i.e. a potential drinkinq water source. Federal MCLs, or more strinqent
state qroundwater standards, are therefore ARARs for the qroundwater at the Site. An exceedence of a federal
MCL siqnifies that qroundwater 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

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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.

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.

The ROD Amendment remedy will 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 groundwater management 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, guarterly monitoring, the Petition for an ESD, and the Petition for a
ROD Amendment, a list of alternatives was assembled to address the Site remedial action objectives and ensure
compliance with the reguirements 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 reguires that the No Action alternative be evaluated at every site to establish a baseline against
which all other alternatives are compared. Under this alternative, no remedial actions would take place and
the Site would remain in its present condition.

Capital cost:
Maintenance and m
Estimated present
Estimated time to

Note: The $10,000

>nitoring cost:
net worth:
implement:

maintenance and moni

0

$10,000
$22,000
None

cost is not an

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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:

Institutional controls
Monitoring

Geosynthetic clay cap

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
guality, groundwater guality, 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 landfill cap would be constructed as specified in 35 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 erosion of the landfill cover from sheet flow would not cause degradation of adjacent wetlands, meet
local stormwater retention reguirements, and allow for the monitoring of surface water
runoff at distinct discharge points.

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.
On-Site treatment would be reguired only if pretreatment standards were exceeded during this action.

Capital cost:

Annual maintenance and monitoring
Estimated present net worth:
Estimated time to implement:

$7,054,000

cost:	$129,000

$8,655,000
6 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:

•	Institutional Controls

•	Monitoring

•	Modified Geosynthetic Cap

•	Natural Attenuation Groundwater Remedy, with conditional reguirement for installation of the
active pump-and-treat system reguired 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 guality,

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groundwater quality, and the condition of the landfill cap. Groundwater sampling and analysis would likely be
done on a periodic basis. 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:

•	Recontouring and regrading of existing cover;

•	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 regraded area with a vibratory compactor of at least 10-	tons
total weight);

•	Installation of a 40-mil linear low density polyethylene liner;

•	Installation of a drainage layer of either 12 inches of sand/gravel or a geonet;

•	Installation of a geofabric between the drainage layer and the soil cover above;

•	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

•	Final grading of the total cover to no less than 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.

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 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.

$4,500,000
$129,000
$6,101,000
6 months

X.	COMPARATIYE EVALUATION OF ALTERNATIVES

Capital cost:

Annual maintenance and monitoring cost:
Estimated present net worth:

Estimated time to implement:

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 addresses whether a remedy provides adequate

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protection of human 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 reguirements. The selected remedy must meet this criteria or waiver of the ARAR
must be obtained.

PRIMARY BALANCING CRITERIA

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 consulation with the IEPA, has
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 conseguently, the present and future risks posed
by the Site would not be adeguately addressed, and further leachate generation and releases of contaminants
to the environment would not be prevented.

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: each 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 Assessment
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-bearingunit downgradient of the Site is limited. The vinyl chlorideplume 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

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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 effectively
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 IEPA's recommendation that, although the Site was closed pursuant to 35 IAC 807, certain
reguirements 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 reguirements of 35 IAC 811.314 are relevant and
appropriate to the landfill cap to be constructed as part of the final remedy for the Site: (1) alternative
specifications for the low permeability layer provided that performance is egual to or superior to the
performance of a layer meeting the reguirements of subsections (b)(3)(A)(i) and (b)(3)(A)(ii) [35 IAC
813.314(b) (3) (A) (iii) a 35 IAC 811.314 (b) (3) (C)]; and (2) preparation and compaction reguirement (35 IAC
811.314(b)(3)(B)(iii)].

Only Alternatives 7 and 12 would comply with all chemical, action, and location specific ARARs associate with
the Site. Other remedial alternatives exist which would not reguire 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 reguires replacement on a 2 to 1 ratio.)

The U.S. EPA, in consultation with the IEPA, has determined that Alternative 12 would also comply with ARARs,
including relevant and appropriate landfill cap reguirements 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 reguire 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 ensuring
that the cap is not damaged by standing water.

Alternative 7, which reguires groundwater extraction, would be effective in preventing further migration of
the vinyl chloride and would ultimately eliminate the threat posed by this media through extraction and
treatment. Alternative 12, which reguires 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.

Reduction of Toxicity, Mobility or Volume: None of the alternatives would reduce the toxicity or volume of
the in-situ landfill wastes. Alternative 1 would only reguire 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 Ig/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
egually 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

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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-established protective
measures would sufficiently ensure worker 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.)

(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 reguire 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 reguired 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 reguired 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 borings. It is expected that further difficulties 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.

3 U.S. EPA, Office of Solid Waste and Emergency Response Policy on Floodplains and Wetland Assessments
for Cercla Actions. August 1985.

The natural attenuation remedy in Alternative 12 would reguire no construction and, as such, is guite
implementable. In addition, implementing the natural attenuation remedy would eliminate the concern with
adverse impacts to 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 and long-term O&M costs to
implement the pump-and-treat component of the June 30, 1993, ROD. By contrast, the alternate remedy would
reguire 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:

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ALTERNATIVE

COSTS
O&M

Capital

PNW

1. No Action

$0

$10,000

$22,000

7. Access Restrictions,

Construct Geosynthetic Clay
Cover, Groundwater
Extraction System, and
Monitoring

$7,054,000 $129,000 $8,655,000

12. Access Restrictions,

Modified Landfill Cover,

Natural Attenuation,

Contingent Pump-and-Treat, $4,500,000 $129,000 $6,101,000
and Monitoring

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 residents of Woodstock, as
well as the Agency's responses thereto, are 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, be cost-effective, and will utilize permanent solutions to the maximum extent practicable.

The major, elements of this alternative include revising the landfill cap component and the groundwater
pump-and-treat reguirement of the remedy selected in the June 30, 1993 ROD.

Landfill Cap: As modified, the landfill cap parameters comprise:

Recontouring and regrading of existing cover;

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);

Installation of a 4.0-mil linear low density polyethylene liner;

Installation of a drainage layer of either 12 inches of sand/gravel or a geonet;

Installation of a geofabric between the drainage layer and the soil cover above;

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

Final grading of the total cover to no less than 2.0 percent slope, after accounting for
anticipated settlement.

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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 reguired 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 reguired 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 reguirement 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, reguired 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
reguired 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
subseguent 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 whether additional measures will be reguired 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 Monitoring: Long-term monitoring of groundwater 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 freguency; and identification and monitoring of areas
containing higher contaminant concentrations.

5-Year Review: At each 5-year review or earlier, as necessary, the U.S. EPA, in consultation with the IEPA,
will evaluate the following criteria in order to determine the need for implementation of the contingent
pump-and-treat remedy:

•	Comparison of existing contaminant levels throughout the plume to MCLs;

•	Trends in contaminant concentrations, if any;

•	Effectiveness of the source control measures at cutting-off the source of contamination at the
Site from the down gradient boundary;

•	Potential reduction in restoration time-frames to less than 30 years;

•	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 reguirements 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 remedy.

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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 protects the environment from the potential risks posed
by contaminants discharging to ground water, the Kishwaukee River, 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 10 -1 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 is added. For
example, modeling, demonstrates that 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 ensure less than E-inch annual infiltration through the barrier layer (shown respectively as
the peak daily head and average annual head outputs in the HELP model). A geonet is an excellent synthetic
alternative, and may be more cost-effective than gravel, 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, 1993, ROD is being retained only as a contingent component of the
remedy, and one of the 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:

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A gas venting system will reduce potential risks due to the landfill gases.

Excavation and consolidation of contaminated sediments:

The U.S. EPA has reguired 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-term risks Dust control measures will mitigate risks as well.
Mitigative 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)) reguires 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,
reguirement, 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,
reguirements, criteria or limitations (ARARs). The 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 aguifers underlying the Site have been designated as Class I
aguifers, 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 aguifer, 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 guality standards promulgated
under Title 35, Subtitle F, Chapter I, Part 620.

To the extent that these state ground water
guality standards listed under 620.410 are more
stringent that the federal MCLs, MCLGs greater
than zero, and the SMCLs, the state standards are
ARARs for the ground water at the Site.

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: Section 304 of the Clean Water. Act (CWA)
establishes Ambient Water Quality Criteria (AWQC)
for protection of human health and aguatic life.

The AWCQ are considered relevant and appropriate

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at Superfund sites where a release or threat of 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.S. 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 activities 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
Conservative Chapter 1, Subchapter C, Part 1075
Illinois Administrative Rules, require that actions
must be performed to conserve the endangered or
threatened species located 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-specific ARARs are requirements that define acceptable treatment and
disposal procedures for hazardous substances.

(1) Federal ARARs:

a. Pretreatment Standards: In the event that a pump-

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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.

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.

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 passed, in large part,
to address landfill cap failures under the old 807
standards. In general, the new Illinois
regulations were more extensive 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

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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 appropiate 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.

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
above, in making a relevant and appropiate
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.

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This remedy will require the installation of a
geomembrane barrier layer. (The Agency has
determined that a geomembrane will minimize the
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 layer:

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.

iii)	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 geomembrone shall have strength to
withstand the normal stresses imposed by
the waste stabilization process.

iii)	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
provide equivalent or superior performance to
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 0.91 meter
(3 feet) .

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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 reguire only
sufficient cover to protect it from other forms of
damage, such as heavy eguipment, root penetration,
or intrusive activities (human or animal). A 24-
inch protective cover, as recommended by the U.S.
EPA guidance, is fully adeguate for this landfill.
In addition, the combination of 18 inches of
rooting zone and 6 inches of top soil is more than
adeguate to support vegetative cover.

Slope: The remedy includes, Final grading of the
total cover to no less than 2.0 percent slope,
after accounting for anticipated settlement. The
reguirement 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
reguirement from three (3) to two (2) percent.
The rationale for doing so in the case of this
Site is: (1) the average waste thickness is
approximately 7 feet, and is, generally uniform;
(2) the landfill stopped accepting waste in 1975,
and much of the anticipated settlement has already
occurred; and (3) localized differential
settlement is expected to occur, but will be
repaired as necessary during the operation &
maintenance (O&M) phase, once the remedial action
is completed.

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
reguirements must be met for POTW discharge.

Groundwater Management Zone: 35 IAC, Part 620.250
which provides for the establishment of a
groundwater management zone is an ARAR for the
Site.

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3.	Cost-Effectiveness: Cost effectiveness is determined 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 adeguate 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 cap. No
unacceptable short-term risks will be caused by implementation of the remedy.

4.	Utilization of Permanent Solutions and 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 adeguate protection of human health and the environment within five years after
commencement of the remedial action, in accordance 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.

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FIGURES

WOODSTOCK MUNICIPAL LANDFILL SUPERFUND SITE
WOODSTOCK, MCHENRY COUNTY, ILLINOIS
JULY 1998

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APPENDIX A

RESPONSIVENESS SUMMARY
WOODSTOCK MUNICIPAL LANDFILL SUPERFUND SITE
WOODSTOCK, MCHENRY COUNTY, ILLINOIS
JULY 1998

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 peried 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
guestion and answer period was included in the meeting, along with the formal 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

Comment #1: The residents of Woodstock have been informed often by the City of Woodstock
that the landfill project was going to cost approximately $11 million, and that the cost would be
shared egually 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 $11 million. It appears,
instead, that the modified project will cost approximately $4.5-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 $ll-million figure is a result of adding up the ~$3-million costs of the Remedial
Investigation (RI) and Feasibility Study (FS), plus the estimated ~$8-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
Amendment changes have reduced the cost of the remedial action by altering the profile of the
landfill cap, and the groundwater pump-and-treat 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
RI/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 $ll-million figure provided by the City ($3-million for
RI/FS, plus approximately $8-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 put more
waste on the same site, even as part of a transfer station? We are concerned about wet and
leaking material migrating from trucks carrying wastes to and from the transfer station. Local

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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 reguired 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 liguid 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
Control Board (IPCB) has regulations in place with 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 reguire 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 (IEPA) ,
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 that is environmentally acceptable,
that protects human health and the environment, and truly addresses the technical reguirements
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
reguirements 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
reguired 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 (PDI) Report, along with the guarterly
groundwater 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

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concentration? Is it dilution? Is it bioremediation? What is it?

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 potential breakdown pathways for vinyl chloride is a
microbial dehalogenation to ethylene, and subseguent 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 the U.S. EPA's new guidance on natural attenuation the reason that you can
now select natural attenuation as the remedy for the contaminated groundwater, making the
pump-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 Superfund 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. EPA's Response: The Agency has taken up your suggestion on native prairie grasses, and
established an interagency agreement with the Natural Resource Conservation 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.

Comment #10: Once the ROD Amendment is signed, how soon would construction begin on the
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 guickly 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

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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 would be subject to approval to ensure that it is
in compliance with the ROD Amendment and environmentally acceptable.

Comment #12: I am aware that 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 as 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 reguirements. 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.

Comment #13: I am aware that there is groundwater contamination on the site. Is there also
groundwater contamination off-site, and if so where? Are there monitoring wells off-site? Is it
true that there is no restriction on the use of wells surrounding the site [for potable water]?

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. EPA'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 existinig 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 #15: I am very concerned about the proposal to put a waste transfer station at the
Site. I understand that approximately 400 garbage trucks a day would be going to the facility. If
that is the case, won'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
materials to the Site, will fully comply with the ROD Amendment, and will not jeopardize the
integrity of the remedy.

Comment #16: I 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

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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 #17. 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 bioremediation 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
plants, prairie 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.

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 C 2H 3CL 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.

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Comment #20: Once the cap has been put on the landfill, how long will it be 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 reguired. Initially, monitoring will probably be reguired guarterly, 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.

Comment #21: If prairie grasses are used to cover the 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 Kishwaukee cuts that corner off.

U.S. EPA's Response: As stated above, 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 reguired. 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 chemical wastes containing it are stored or have been disposed, such as at
this Site. With respect to the vinyl chloride contamination at this Site, it appears to 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
aguatic 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
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

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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 reguires 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 reguired 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.

Comment #24: RECOMPACTION OF THE EXISTING LAYER

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 antainable 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 cover.

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 reguirement 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 egual 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 reguirement 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 reguirement of this remedy can be gualified by "practicality," and further
agrees that a good measure of "to the extent practical" is the extent to which the regraded
materials can be compacted after three passes with a vibratory compactor of at least 10-tons total
weight.

Comment #25: SLOPE OF THE FINAL LANDFILL COVER GRADE

The proposed remedy includes "Final grading of the total cover to no less than 2.0 percent
slope, after accounting for anticipated settlement."

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The qualifier "...after accounting for anticipated settlement" suggests that the minimum slope
should be greater than 2.0 percent after cap construction in order to allow for some settlement.

CRA believes that a 2.0 percent minimum slope after 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 0.44 feet (0.22 feet) is expected 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 cover
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.

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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
04/07/93

AR

DOC# DATE

1 00/00/00

AUTHOR

RECIPIENT

TITLE/DESCRIPTION	PAGES

Miscellaneous Newspaper Articles, Various	13

Dates

2 00/00/71

3 00/00/84

4 09/05/84

5 04/29/85

6 05/22/85

7 08/02/85

8 06/06/86

Hughes, G.M., et al, U.S. EPA
Illinois State
Geological Survey

Nicholas, J.R., and
Krohelski, J.T.,

U.S. Geological
Survey

Bates, E., U.S. EPA
and Winner, L., IEPA

Hydrogeology of Solid Waste Disposal Sites in 153
Northeastern Illinois

Report Entitled, "Water in Sand and Gravel
Deposits in McHenry County, Illinois"

Preliminary Assessment

Bachunas, C. &

Pratl, A., Ecology &
Environment, Inc.

Bachunas, C. &

Pratl, A., Ecology &
Environment, Inc.

Divner, L., IEPA and
Nelson, S., U.S. EPA

Beale, J., Allied	U.S. EPA

Automotive

Site Inspection Report

Cover Letter for Completed EPA Form-8900
1 Notifications

41

Nelson, S., U.S. EPA Review of Sample Case #4042 Low Soil Metals	12

Nelson, S., U.S. EPA Review of Sample Case #4042 Low Soil Organic	26

24

9 10/02/87 U.S. EPA

HRS Scoring Package

91

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DOC# DATE	AUTHOR	RECIPIENT

10	00/00/88 Hola, H., Weston	Faryan, S., U.S. EPA

11	07/00/88

12	07/22/88 Suburban Laboratori-

es, Inc.

13	08/04/88 Suburban Laboratori- Roy Weston, Inc.

es, Inc.

14	12/00/88	U.S. EPA

15	12/00/88 Tsai, C.	U.S. EPA

16	01/00/89 Tsai, C	U.S. EPA

17	01/03/89 Suburban Laboratori- Matz, S., Ray F.

es, Inc.	Weston, Inc.

18	02/12/89 Nelson, R., U.S. DOI Swale, R., U.S. EPA

19	05/00/89 Tsai, C. U.S. EPA

20	05/24/89 Niedergang, N., U.S. PRPs

EPA

21	06/09/89 U.S. EPA	Waste Management of

Illinois, Inc.

22	06/19/89 Schaefer, R. and	U.S. EPA

Gade, M., U.S. EPA

23	06/26/89 Child, W., IEPA	Constantelos, B.,

U.S. EPA

24	07/26/89 Moeller, D., Arrow Watts, G.M., U.S.

Aluminum Castings,	EPA

Inc.

TITLE/DESCRIPTION	PAGES

Site Assessment	17

Well Sampling Data from 7/88	83

Analysis of Organic Chemical Compounds by Gas 15

Chromatography/Mass Spectrometry: Final

Report

Analysis of Samples Received 7/22/88	7

Chain of Custody Record for Sampling	24

Guidance: "Standard Operating Procedure for	45

the Analysis of Semivolatile Organics in
Drinking Water..."

Guidance: "Standard Operating Procedure for	35

the Analysis of Pesticides/PCBs in Water With
Low Detection Levels," Revised

Analysis of Samples Received 12/22/88	6

U.S. DOI's Comments on the RI/FS Plan	3

Guidance: "Standard Operating Procedure for	41
the Analysis of Volatile Organics With Low
Detection Limits...," Revised

Letter of Potential Liability	7

Notification of Hazardous Waste Site	5

Region V Municipal Settlement Guidance	10

Amendment to the Enforcement Multi	9

Site Cooperative Agreement

Response to 104(e) Inforsation Reguest,	7

Reguest Forwarded to Previous Owner

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DOC# DATE	AUTHOR	RECIPIENT

25	08/16/89 Straw, A., Waste	Fulghum, M., U.S.

Management of	EPA
Illinois, Inc.

26	08/31/89 Caldwell, M., City	Swale, R. and

of Woodstock	Fulghum, M., U.S.

EPA

27	09/01/89 Maher, K., Cromer,	Swale, R. and

Eaglesfield & Maher	Fulghum, M., U.S.

EPA

28	09/19/89 U.S. EPA	Respondents

29	09/19/89 McGuire, M.	U.S. EPA

30	09/26/89 U.S. EPA	Respondents

31	09/29/89 U.S. EPA	Respondents

32	09/29/89 U.S. EPA

33	10/02/89 Garry, R., John J.	Fulghum, M., 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 Warzyn, Inc.	U.S. EPA

38

03/06/90

Swale, R., U.S. EPA Vagt, P., Warzyn

Inc.

TITLE/DESCRIPTION

PAGES

FOIA Reguesting Linking Documentation
Regarding Waste Management

Letter re: Recommendation That Client Approve
8/28/89 Draft Consent Order

Letter re: Recommendation That Client Sign
8/28/89 Draft Consent Order

Administrative Order By Consent, Signature
Pages

Reichert Chevrolet & Oldsmobile Sales, Inc.'s
Signature Agreeing to the Consent Order

Administrative Order By Consent, Amendment #1

Administrative Order By Consent for RI/FS,
Final

News Release: "EPA Identifies 9 New Midwest
Sites for Superfund Cleanup"

Letter Reguesting That Arrow Aluminum
Castings, Inc. Be Released From Liability

News Release: "City of Woodstock, Allied
Chemical Corp. and Others Agree to
Investigate the Woodstock Municipal Landfill
Site"

Response to Reguest for Information on
Wetlands

Guidance: "Interim Policy on CERCLA
Settlements Involving Municipalities or
Municipal Wastes," OSWER Directive #9834.13

Map: RI/FS-Site Base Map with 100 Foot Surve-
y Grid

4

2

2

3

2

8

49

1

3

1

4

33

10

U.S. EPA's Review Comments Concerning the
RI/FS Planning Documents

37

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DOC#	DATE	AUTHOR

39	04/00/90 Warzyn Inc.

40	04/00/90 Warzyn Inc.

41	04/00/90 Warzyn Inc.

RECIPIENT
U.S. EPA
U.S. EPA
U.S. EPA

42	04/09/90 Versar, Inc.

43	04/20/90 Warzyn, Inc.

U.S. EPA
U.S. EPA

44 06/00/90 U.S. EPA

45	06/03/90 Angstmann, J.,

Versar, Inc.

46	06/18/90 La Faire, M., U.S.

EPA

47	07/24/90 Warzyn, Inc.

48	07/24/90 Compuchem.rtp

49	08/08/90 Warzyn, Inc.

U.S. EPA

Lesser, T., U.S. EPA

U.S. EPA
U.S. EPA
U.S. EPA

50	08/13/90 Bosse, M., Versar

Inc.

51	08/15/90 Warzyn, Inc.

52	08/22/90 Clay, D., U.S. EPA

Swale, R., U.S. EPA

U.S. EPA

53 10/17/90 Maher, K., Cromer,
Eaglesfield & Maher

54	10/30/90 Swale, R., U.S. EPA

55	11/00/90 Warzyn Inc.

Swale, R., U.S. EPA
and Washburn, S . ,
IEPA

Residents
U.S. EPA

TITLE/DESCRIPTION	PAGES

QAPP, Vol. 1 of 3, With Appendices A, B and C	360

QAPP, Vol. 2 of 3, Appendices D, E and F	445

QAPP, Vol. 3 of 3, Appendices G, H, I, J, K,	330
and L

Technical Oversight Data Quality Objectives	1

Map: RI/FS-Site Base Map Showing Coordinates-	10
& Sampling Locations

Fact Sheet: "Superfund Study Begins at	8
Woodstock Municipal Landfill"

Community Relations Plan, Final Plan	27

Report on Public Meeting Held 6/13/90	4

Inorganic Analysis Data Sheets	3

Volatile Organics Analysis Data Sheets	2

Inorganic Analysis Data Sheet Marked	8
"Leachate Data"

Fax Cover with Boring Logs From	7
8/1/90-8/13/90

Drawing of X-Sections	2

OSWER Directive No. 9835.15: "Performance of	4
Risk Assessment In Remedial

Investigation/Feasibility Studies Conducted
by PRPs"

Notice of Force Majeure	3

Cover Letter with Well Sampling Results	5

Technical Memorandum: Wetlands Delineation	99

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DOC# DATE	AUTHOR	RECIPIENT

56	11/15/90 Warzyn, Inc.	U.S. EPA

57	12/00/90 Warzyn Inc.	U.S. EPA

58	12/00/90 Warzyn Inc.	U.S. EPA

59	12/00/90 Warzyn Inc.	U.S. EPA

60	12/00/90 Warzyn Inc.	U.S. EPA

61	12/18/90 Warzyn, Inc.	U.S. EPA

62	12/18/90 Warzyn, Inc.	U.S. EPA

63	01/16/91 Bosse, M., Versar,	U.S. EPA

Inc.

64	02/00/91 Warzyn Inc.	U.S. EPA

65	02/00/91 Widman, J., Warzyn	Swale, R., U.S. EPA

Inc.

66	02/01/91 Warzyn, Inc.	Swale, R., U.S. EPA

67	02/01/91 Warzyn, Inc.	Swale, R., U.S. EPA

68	02/04/91 Vagt, P., Marzyn,	Swale, R., U.S, EPA

Inc

69	03/00/91 U.S. EPA

70	03/14/91 Anderson, D., City	Bacon, J.M., McHenry

of Woodstock	County Dept. of

Health

71	04/03/91

TITLE/DESCRIPTION	PAGES

Map: RI/FS-Water Table Contour Map (Sept. 20- 10
, 1990)

Technical Memorandum: Hydrogeological	160

Investigation, Phase 1

Technical Memorandum: Preliminary Baseline	32

Risk Assessment

Technical Memorandum: Source Characterization 132

Technical Memorandum: Surface Water/Sediment	47

Evaluation

Map: RI/FS-Surface Water & Sediment Sample L- 10
ocation Map

Map: RI/FS-Water Table Contour Map (Nov. 5, - 10
1990)

QAPP: Oversight Acceptance of Collocated	140

Samples

Technical Memorandum: Hydrogeological	148

Investigation, Phase 1

Technical Memorandum: Surface Water/Sediment	50

Evaluation

Fax Cover with Field Boring Logs (1/91)	5

Fax Cover with Field Boring Logs (1/91)	3

Groundwater Sampling Parameters (Phase I:	2

Round 2; Phase II: Round 1)

Fact Sheet: "Wooodtock Municipal Landfill	6

Superfund Site"

Invitation to Informational Meeting Regarding	2

the RI

Statistical Summary of Sediment Background
Data for RI/FS

1

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DOC# DATE

AUTHOR

RECIPIENT

72 04/15/91 Bosse, M., Versar	Swale, R., U.S. EPA

73	04/18/91 Maher, K., and

Ellis, M.

74	04/22/91 Vagt, P., Warzyn,

Inc

75	04/23/91 Vagt, P., Warzyn,

Inc

76	05/10/91 Niedergang, N., U.S.

EPA

77	06/18/91 Hudak, D., U.S. DOI

78	07/00/91 Warzyn Inc.

79	07/02/91 Nelson, R., U.S. DOI

80	08/06/91 Swale, R., U.S. EPA

81	06/08/91 Warzyn, Inc.

82	10/00/91 Bollo, N., U.S. EPA

83	10/04/91 Maher, K., Cromer,

Eaglesfield & Maher

84	02/12/92 Bolen, B., U.S. EPA

U.S. EPA

Swale, R., U.S. EPA

Swale, R., U.S. EPA

Maher, K., Cromer,
Eaglesfieid & Maher

Swale, R., U.S. EPA

U.S. EPA

Swale, R., U.S. EPA

Vagt, P., Warzyn
Inc.

U.S. EPA

Maher, K., Cromer,
Eaglesfield & Maher

Bollo, N., U.S. EPA

Vagt, P., Warzyn
Engineering Inc.

85 05/05/92 Bolen, W., U.S. EPA Widman, Warzyn Inc.

86	05/15/92 Vagt, P., Warzyn

Inc.

87	05/20/92 Vagt, P., Warzyn

Inc.

Bolen, B., U.S. EPA
Bolen, W., U.S. EPA

TITLE/DESCRIPTION	PAGES

Transmittal Letter with List of Solid Waste	7

Disposal Sites in Northeastern Illinois

Respondents' Reply to U.S. EPA's Response to	11

Notice of Dispute

Phase I: Round 2; Phase II: Round 1 Sampling	25

Results with Map & Laboratory Qualifiers

Correction for Data of 4/3/91	3

Final Decision and Resolution of Dispute	2

U.S. DOI's Comments on the Draft FS	3

QAPP Addendum With Attachments	28

U.S. DOI's Comments on the RI Report	40

U.S. EPA's Comments an the Draft RI Report	40

Inorganic and Organic Analysis Data Sheets	52

Response to Letter of October 4, 1991	3

Letter Discussing Status of RI/FS and the AOC	5

Respondents' (PRPs) Performance

U.S. EPA's Comments on the 2nd Draft RI	10

Report

U.S. EPA's Review and Comments on the March	2

1992 RI Report/Ecological Assessment

Reguest for Clarification on U.S. EPA	2

Comments Dated May 5, 1992

IEPA's Comments on the Baseline Risk	31

Assessment, Final RI Report and Warzyn's
Response to IEPA's Comments

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DOC#	DATE

88	05/21/92

89	06/00/92

90	06/00/92

91	06/04/92

92	06/11/92

93	06/12/92

94	07/16/92

95	07/31/92

96	08/04/92

97	09/09/92

98	10/00/92

99	10/30/92

100	12/08/92

101	12/14/92

102	12/22/92

103	02/24/93

AUTHOR
IDPH & ATSDR
Warzyn Inc.

Warzyn Inc.

Widman, J. , Warzyn
Inc.

Vagt, P., Warzyn
Inc.

Widman, J., Warzyn
Inc.

Bolen, W., U.S. EPA

Vagt, P., Warzyn
Inc.

Bolen, W., U.S. EPA
Bolen, W., U.S. EPA
U.S. EPA

Maher, K., Cromer,
Eaglesfield & Maher

Bolen, W.,U.S. EPA

Vagt, P., Warzyn
Inc.

Vagt, P., Warzyn
Inc.

Falco, C., IEPA

RECIPIENT
U.S. EPA

Woodstock PRP Group
Steering Committee

Woodstock PRP Group
Steering Committee

Bolen, W., U.S. EPA

Bolen, W., U.S. EPA

Bolen, W., U.S. EPA

Widman, J., Warzyn
Inc.

Bolen, W., U.S. EPA

Falco, C., IEPA

Vagt. P., Warzyn
Inc.

Bollo, N., U.S. EPA

Vagt, P., Warzyn
Inc.

Bolen, W., U.S. EPA
Bolen, W., U.S. EPA
Bolen, W., U.S. EPA

TITLE/DESCRIPTION

PAGES

Interim Preliminary Health Assessment
Final Remedial Investigation Report, Vol. I

Final Remedial Investioation Report, Vol. II

Response to U.S. EPA's Comments on the RI
Report Dated May 20, 1972 re:
Arsenic/Aluminum Methods

Response to Final U.S. EPA's Comments re: RI
Report

Response to U.S. EPA's Comments on the Final
Draft RI Report Dated May 20, 1992

U.S. EPA's Response to 7/10/92 FS Schedule

Schedule for the FS

Reguest for IEPA's Review of the Alternatives
Array

Letter re: U.S. EPA's Comments on the Draft
Alternatives Array

Fact Sheet: "Remedial Investigation Complete"

Letter re: RPM's Directions to Remove
Portions of Text Discussing Institutional
Controls in the FS

Letter re: U.S. EPA's Second Disapproval
Notice for the Draft FS

Reguest for Meeting to Discuss U.S. EPA's
12/8/92 Comments on the First Draft FS Report

Letter re: Submitting Second Draft of FS in
Accordance With the Schedule

IEPA's Comments on the ARAR's and the FS

18

301

798

6

1

2

6

5

2

3

6

7

10

1

1

4

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DOC# DATE	AUTHOR	RECIPIENT

104	03/04/93 Bollo, N., U.S. EPA Maher, K., Cromer,

Eaglesfield & Maher

105	03/15/93 Bolen, W., U.S. EPA Vagt, P., Warzyn

Inc.

106	03/17/93 Bolen, W. , U.S. EPA Vagt, P., Warzyn

Inc.

107	03/22/93 Vagt, P., Warzyn	Bolen, W. , U.S. EPA

108	04/00/93	U.S. EPA

109	4/00/93 Bolen, W., U.S. EPA U.S. EPA

TITLE/DESCRIPTION

Letter re: Reasons For Believing that MCLs
Are Not ARARs

PAGES
3

Letter re:	Third Disapproval Notice for the	6

FS Report

Letter re:	Third Disapproval Notice for the	1

FS Report,	Follow-up to 3/15/93 Letter

Reguest for Clarification on U.S. EPA	4

Comments Dated 3/15/93 re: the Draft FS

Report

Feasibility Study	0

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

DOC#	DATE	AUTHOR

1	10/02/85	Porter, J.W., OSWER

2	10/01/86	OERR/OSWER

3	12/01/87	OERR/OWPE

08/08/88 OERR

10/01/88 OSWER/OERR

02/00/91 OERR

7 07/00/91 U.S. EPA

RECIPIENT
U.S. EPA

U.S.	EPA

U.S.	EPA

U.S.	EPA

U.S.	EPA

U.S. EPA

U. S. EPA

TITLE/DESCRIPTION	PAGES

CERCLA Compliance With Other Environmental	19

Statutes, Final, OSWER #9234 0-2

Superfund Public Health Evaluation Manual,
Final, OSWER #9285 4-1

A Compendium of Superfund Field Operations
Methods, Final, OSWER #9355 0-14

CERCLA Compliance With Other Laws Manual,
Draft, OSWER #9234 1-01

Guidance on Oversite of Potentially
Responsible Party Remedial Investigations and
Feasibility Studies, Vol. 1, Final, OSWER
#9835.1 (d)

500

550

245

Guidance for Conducting Remedial	390

Investigations and Feasibility Studies Under
CERCLA, Final, OSWER #9355 3-01

Conducting Remedial Investigations/Feasibili- 301
ty Studies for CERCLA Municipal Landfill
Sites, OSWER #9355.3-11

124

8 07/00/91 U.S. EPA	U.S. EPA

Guidance on Oversite of Potentially	193

Responsible Party Remedial Investigations and
Feasibilily Studies, Final, Vol. 2, OSWER
#9835.1 (c)

-------
U.S. EPA ADMINISTRATIVE RECORD
WOODSTOCK MUNICIPAL LANDFILL
WOODSTOCK, ILLINOIS
UPDATE #1

DOC# DATE

AUTHOR

06/30/93

RECIPIENT

1 10/09/92 Bolen, W., U.S. EPA Vagt, P., Warzyn

Inc.

2 00/00/93 Citizens

U.S. EPA

3 04/07/93 U.S. EPA

Public

4 04/12/93 Bolen, W. , U.S. EPA Vagt, P., Warzyn

Inc.

5 05/12/93 U.S. EPA

Public

6 05/26/93 U.S. EPA

Public

7 05/26/93 U.S. EPA

Public

8 06/04/93 Clifton, T., City of Bolen, W. , U.S. EPA
Woodstock

9 06/04/93 Woodstock Municipal U.S. EPA
Landfill Steering
Committee

10 06/17/93 Lawson, D., U.S. EPA Cowgill, D., U.S.

EPA

AR

TITLE/DESCRIPTION	PAGES

Letter re: U.S. EPA's Comments on the Draft	4

FS

Citizens' Signatures Reguesting a 30 Day	2

Extension to the Public Comment Period

Public Notice: Announcement of the Public	1

Comment Period re: the Remedial Alternatives,

Which Ends May 6, 1993

Letter re: U.S. EPA's Receipt of the Draft FS	1

Public Notice: Public Comment Period Extended	1

Until June 5, 1993

News Release: "EPA To Hold Workshops on	1

Woodstock Superfund Site June 2"

Public Notice: U.S. EPA To Hold Workshops on	1

the Woodstock Superfund Site on June 2, 1993.

City of Woodstock's Public Comment to the	7

Proposed Plan

Public Comments on the Proposed Plan (Certain 206
Appendices Omitted, See List of Appendices)

Field Trip Report

6

-------
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)

06/30/93

DOC# DATE

AUTHOR

08/00/90 U.S. EPA

RECIPIENT

U.S. EPA

TITLE/DESCRIPTION

CERCLA Site Discharges to POTWs,
EPA/540/6-90/005

PAGES
226

-------
DOC# DATE	AUTHOR

U.S. EPA ADMINISTRATIVE RECORD
WOODSTOCK MUNICIPAL LANDFILL
WOODSTOCK, ILLINOIS
UPDATE #2

07/08/93

RECIPIENT

1 06/30/93

Adamkus, V. , U.S.
EPA

Recipients

AR

TITLE/DESCRIPTION	PAGES

Record of Decision

202

-------
U.S. ENVIRONMENTAL PROTECTION AGENCY
REMEDIAL ACTION

ADMINISTRATIVE RECORD
FOR

WOODSTOCK MUNICIPAL LANDFILL SITE
WOODSTOCK, ILLINOIS

UPDATE #3
MARCH 18, 1998

NO. DATE	AUTHOR	RECIPIENT

1	04/00/93 Warzyn Inc.	U.S. EPA

TITLE/DESCRIPTION	PAGES

Feasibility Study for	423

the Woodstock Municipal
Landfill Site

04/28/93 U.S. EPA

Transcript of the
April 28, 1993 Public
Meeting re: the Wood-
stock Municipal
Landfill Site

146

06/00/93

06/04/93

PRC

Environmental
Management,
Inc.

Vagt, P.,
Warzyn Inc.

U.S. EPA

Bolen, W.,
U.S. EPA

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

78

08/ /93

Gade, M. ,
I EPA

U.S. EPA

IEPA's Declaration for
the Record of Decision
for the Woodstock Muni-
cipal Landfill Site w/
Attached Cover Letter

03/00/95

Conestoga-
Rovers &
Associates

U.S. EPA

Predesign Work Plan
for the Woodstock
Municipal Landfill
Site

107

05/01/95

Mishra, M.,
PRC

Environmental
Management,
Inc.

0'Grady, J.,
U.S. EPA

Letter Forwarding
Attached Field Over-
sight Summary No. 1:
Remedial Design Field
Oversight for the
Woodstock Municipal
Landfill Site

47

-------
Woodstock Municipal Landfill AR

Update #3
Page 2

NO.

DATE
09/01/95

AUTHOR

Ratliff, G. ,
I EPA

RECIPIENT

0'Grady, J.,
U.S. EPA

TITLE/DESCRIPTION

FAX Transmission
Forwarding Attached
Information re: Title
35 IAC Part 811.314

PAGES
2

10/21/95

Isbell, J.,
City of
Woodstock

0'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.

0'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.,	O'Grady, J.,	Letter re: Woodstock

Conestoga-	U.S. EPA	PRP Group's Reguest to

Rovers &	Have the Groundwater

Associates	Analytical Parameter

List Reduced for the
March 1996 Quarterly
Monitoring Event

12	03/01/96 O'Grady, J.,	Wanner, S.,	Letter re: U.S. EPA's

U.S. EPA	Conestoga-	Reply to Woodstock PRP

Rovers &	Group's Reguest to Have

Associates	the Groundwater Parameter

List Reduced for the
March 1996 Quarterly
Monitoring Event

13	03/07/96 Pochron, W.,	O'Grady, J.,	Letter re: Second

Conestoga-	U.S. EPA	Quarterly Sampling

Rovers &	Event for the Woodstock

Associates	Municipal Landfill

Site

20

14

03/11/96

Mishra, M.,
PRC

Environmental
Management,
Inc.

0'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 Landfill AR

Update #3
Page 3

NO.
15

DATE

AUTHOR

16

03/13/96 Ratliff, G.,
I EPA

03/14/96 Ratliff, G.,
I EPA

RECIPIENT

0'Grady, J.,
U.S. EPA

0'Grady, J.,
U.S. EPA

TITLE/DESCRIPTION

FAX Transmission
Forwarding Attached
Information re: Title
35 IAC Part 807.305
Cover Reguirements

FAX Transmission
Forwarding Attached
Information re: Title
35 IAC Part 814.501
and Part 814.502
Concerning the Two
Year Windows for
807 Landfills

PAGES
2

17

03/25/96

0'Grady, J.,
U.S. EPA

Ratliff, G.,
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

18	03/25/96 O'Grady, J.,	Wanner, S.,	Letter re: U.S. EPA's

U.S. EPA	Conestoga-	Comments on the January

Rovers &	1996 Sensitive Environ-

Associates	mental Study Report,

Appendix I of the
Predesign Investigation
Report for the Wood-
stock Municipal Landfill
Site

19	03/26/96 O'Grady, J.,	Wanner, S.,	Letter re: a Waste

U.S. EPA	Conestoga-	Transfer Station on the

Rovers &	Woodstock Municipal

Associates	Landfill Site w/Attach-

ment

20

03/27/96

Ratliff, G.,
IEPA

0'Grady, J.,
U.S. EPA

FAX Transmission
Forwarding Attached
Information re:
Relevancy of Title
35 IAC Part 811 with
the Applicability of
Part 807

-------
Woodstock Municipal Landfill AR

Update #3
Page 4

NO.
21

DATE
04/00/96

22

04/00/96

AUTHOR

Conestoga-
Rovers &
Associates

Conestoga-
Rovers &
Associates

RECIPIENT

U.S. EPA

U.S. EPA

TITLE/DESCRIPTION

Final Predesign
Investigation Report:
Volume 1 of 2 (Text,
Figures and Tables)
for the Woodstock Muni-
cipal Landfill Site

Final Predesign
Investigation Report:
Volume 2 of 2
(Appendices) for the
Woodstock Municipal
Landfill Site

PAGES
137

498

23

04/01/96

24

04/05/96

25

04/22/96

26

06/07/96

Ratliff, G. ,
I EPA

Mishra, M.,
PRC

Environmental
Management,
Inc.

Wanner, S.,
Conestoga-
Rovers &
Associates

Wanner, S.,
Conestoga-
Rovers &
Associates

0'Grady, J.,
U.S. EPA

0'Grady, J.,
U.S. EPA

0'Grady, J.,
U.S. EPA

0'Grady, J.,
U.S. EPA and
G. Ratliff,
IEPA

FAX Transmission re:
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
Attached Field Over-
sight Summary No. 3:
Interim Monitoring
Field Oversight for
the Woodstock Muni-
cipal Landfill Site

Letter re: CRA's
Responses to U.S. EPA's
Comments on the Final
Predesign Investigation
Report for the Woodstock
Municipal Landfill Site

Letter re: Monthly
Progress Report for
May 1996 for the Wood-
stock Municpal Landfill
Site

26

23

74

27

06/17/96

Wanner, S.,
Conestoga-
Rovers &
Associates

0'Grady, J.,
U.S. EPA

Letter re: Woodstock
PRP Group's Reguest to
Modify the Groundwater
Analytical Parameter
List

-------
Woodstock Municipal Landfill AR

Update #3
Page 5

NO.
28

DATE
06/17/96

AUTHOR

0'Grady, J.,
U.S. EPA

RECIPIENT

Wanner, S. ,
Conestoga-
Rovers &
Associates

TITLE/DESCRIPTION

Letter re: U.S. EPA's
Response to Woodstock
PRP Group's Reguest to
Modify the Groundwater
Analytical Parameter
List

PAGES
2

29

06/20/96

Isbell, J.,
City of
Woodstock

0'Grady, J.,
U.S. EPA

City of Woodstock's
Reguest 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.

0'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,
Inc.

0'Grady, J.,
U.S. EPA

Letter re: PRC's
Review of Analytical
Data for Investigative
Split Samples Collected
in March 1996 for the
Woodstock Municipal
Landfill Site

33

08/08/96

Wanner, S.,
Conestoga-
Rovers &
Associates

0'Grady, J.,
U.S. EPA and
G. Ratliff,
IEPA

Letter re: Monthly
Progress Report for
July 1996 for the
Woodstock Municipal
Landfill Site

22

34

08/23/96

Wanner, S.,
Conestoga-
Rovers &
Associates

0'Grady, J.,
U.S. EPA

Letter re: September
1996 Interim Monitoring
Program Event for the
Woodstock Municipal
Landfill Site

-------
Woodstock Municipal Landfill AR

Update #3
Page 6

NO.
35

DATE
09/26/96

36

37

38

10/18/96

11/08/96

11/21/96

AUTHOR

Mishra, M.,
PRC

Environmental
Management,
Inc.

Wanner, S.,
Conestoga-
Rovers &
Associates

0'Grady, J.,
U.S. EPA

0'Grady, J.,
U.S. EPA

RECIPIENT

0'Grady, J.,
U.S. EPA

0'Grady, J.,
U.S. EPA

Wanner, S.,
Conestoga-
Rovers &
Associates

Frehner, R.,
Conestoga-
Rovers &
Associates

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 Landfill
Site

PAGES
29

39

40

11/26/96

12/02/96

41

12/20/96

Wanner, S.,
Conestoga-
Rovers &
Associates

0'Grady, J.,
U.S. EPA

Wanner S. and
W. Pochron;
Conestoga-
Rovers &
Associates

0'Grady, J.,
U.S. EPA

Frehner, R.,
Conestoga-
Rovers &
Associates

0'Grady, J.,
U.S. EPA and
G. Ratliff,
IEPA

November 1996 Wetlands	40

Environmental Evaluation
Report for the Woodstock
Municipal Landfill Site

Letter re: the Draft	4

Petition for 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

-------
Woodstock Municipal Landfill AR

Update #3
Page 7

NO.
42

DATE
12/30/96

43

01/30/97

44

02/07/97

AUTHOR

0'Grady, J.,
U.S. EPA

Mishra, M.,
PRC

Environmental
Management,
Inc.

Wanner, S.,
Conestoga-
Rovers &
Associates

RECIPIENT

Frehner, R. ,
Conestoga-
Rovers &
Associates

0'Grady, J.,
U.S. EPA

0'Grady, J.,
U.S. EPA

TITLE/DESCRIPTION

Letter re: U.S. EPA's
Comments on the October
1996 Draft Petition
for an Explanation of
Significant Difference
for the Woodstock
Municipal Landfill Site

Letter re: PRC's
Review of Analytical
Data for Split Samples
Collected in September
1996 for the Woodstock
Municipal Landfill Site

Letter re: Monthly
Progress Report for
January 1997 w/Attached
City of Woodstock Letter
Concerning Rezoning of
the Woodstock Landfill
Site

PAGES
4

45

03/05/97

0'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. ,
Conestoga-
Rovers &
Associates

0'Grady, J.,
U.S. EPA

Letter re: April 1997
Semi-Annual Groundwater
Sampling Event for the
Woodstock Municipal
Landfill Site

47

03/07/97

Wanner, S.,
Conestoga-
Rovers &
Associates

0'Grady, J.,
U.S. EPA and
G. Ratliff,
IEPA

Letter re: Monthly
Progress Report for
February 1997 for the
Woodstock Municipal
Landfill Site

-------
Woodstock Municipal Landfill AR

Update #3
Page 8

NO.
48

DATE
03/10/97

AUTHOR

Mishra, M.,
PRC

Environmental
Management,
Inc.

RECIPIENT	TITLE/DESCRIPTION

0'Grady, J.,	Letter re: PRC's

U.S. EPA	Technical Review Comments

on the February 1997
Petition for an Explana-
tion of Significant
Difference at the Wood-
stock Municipal Landfill
Site

PAGES
6

49

03/11/97

50

03/11/97

51

03/18/97

52

03/2 /97

0'Grady, J.,
U.S EPA

0'Grady, J.,
U.S. EPA

0'Grady, J.,
U.S. EPA

Frehner, R.,
Conestoga-
Rovers &
Associates

Frehner, R. ,
Conestoga-
Rovers &
Associates

Frehner, R.,
Conestoga-
Rovers &
Associates

Frehner, R.,
Conestoga-
Rovers &
Associates

Mishra, M.,
PRC

Environmental
Management,
Inc.

Letter re: U.S. EPA's
Comments on 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: March 20,

1997	Meeting Concerning
Work to be Performed at
the Woodstock Municipal
Landfill Site

53

04/00/97

Conestoga-
Rovers &
Associates

U.S. EPA

Petition for an Explan-
ation of Significant
Differences for the
Woodstock Municipal
Landfill Site

82

54

04/00/97

Conestoga-
Rovers &
Associates

U.S. EPA

Wetlands Environmental
Evaluation Report for
the Woodstock Municipal
Landfill Site

46

-------
Woodstock Municipal Landfill AR

Update #3
Page 9

NO.
55

DATE
04/14/97

AUTHOR

Frehner, R.,
Conestoga-
Rovers &
Associates

RECIPIENT

0'Grady, J.,
U.S. EPA

TITLE/DESCRIPTION

Letter re; Infiltration
Estimates and Cost
Estimate of Various
Capping Scenarios for
the Woodstock Municipal
Landfill Site

PAGES
37

56

04/18/97

57

04/21/97

58

04/21/97

Wanner, S.,
Conestoga-
Rovers &
Associates

0'Grady, J.,
U.S. EPA

0'Grady, J.,
U.S. EPA

0'Grady, J.,
U.S. EPA

Frehner, R.,
Conestoga-
Rovers &
Associates

Frehner, R.,
Conestoga-
Rovers &
Associates

Letter re: CRA's
Responses to U.S. EPA's
Comments on the November
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

59

05/07/97

Fabinski, L.,

USDHSS/PHS/

ATSDR

0'Grady, J.,
U.S. EPA

April 30, 1997 Public
Health Assessment for
the Woodstock Municipal
Landfill Site w/Attached
Cover Letter

52

60

05/14/97

PRC

Environmental
Management,
Inc.

U.S. EPA

Technical Memorandum:
Simulation of Surface
Water Infiltration and
Evaluation of Cap
Construction Costs for
the Woodstock Municipal
Landfill Site

89

61

07/09/97

Wanner, S.,
Conestoga-
Rovers &

0'Grady, J.,
U.S. EPA and
G. Ratliff,
IEPA

Letter re: Monthly
Progress Report for
June 1997 for the
Woodstock Municipal
Landfill Site

62

08/01/97

City of
Woodstock/
AlliedSignal,
Inc.

U.S. EPA

Petition to Amend the
Record of Decision for
the Woodstock Muni-
cipal Landfill Site

604

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Woodstock Municipal Landfill AR

Update #3
Page 10

NO.
63

DATE
08/04/97

AUTHOR

Flynn, D.;

Phillips,

Lytle,

Hitchcock,

Blaine &

Huber

RECIPIENT

Alcamo, T. ,
U.S. EPA

TITLE/DESCRIPTION

Cover Letter Forward-
ing the Petition to
Amend the Record of
Decision for the
Woodstock Municipal
Landfill Site

PAGES
2

64

10/27/97

Frehner, R.,
Conestoga-
Rovers &
Associates

0'Grady, J.,
U.S. EPA

Letter re: CRA's
Proposed Landfill Cap
for the Woodstock Muni-
cipal Landfill Site

65

11/18/97

Mishra, M.,
PRC

Environmental
Management,
Inc.

0'Grady, J.,
U.S. EPA

Memorandum re: Cost
Estimate for Cap at
the Woodstock Muni-
cipal Landfill Site

66

12/05/97

Flynn, D.;
Phillips,
Lytle,
Hitchcock,
Blaine &
Huber, LLP

Muno, W. ,
U.S. EPA

Letter re: the Petition
to Amend the Record of
Decision for the Wood-
stock Municipal Landfill
Site

67

12/19/97

01/02/98

Flynn, D.;
Phillips,
Lytle,
Hitchcock,
Blaine &
Huber, LLP

Wanner, S.,
Conestoga-
Rovers &
Associates

Muno, W. ,
U.S. EPA

0'Grady, J.,
U.S. EPA and
G. Ratliff,
IEPA

Letter re: the Cap ARAR
Issue at the Woodstock
Municipal Landfill Site
w/Attached December 11,
1997 Circuit Court
Summary Judgment in
City of Woodstock vs.
Illinois Environmental
Protection Agency

Letter re: October 1997
Semiannual Monitoring
Event at the Woodstock
Municipal Landfill Site

40

69	01/12/98 O'Grady, J.,	Ratliff, G.,	Letter re: U.S. EPA's

U.S. EPA	IEPA	Reguest for Illinois

ARARs for the Proposed
Plan and Record of Decision
Amendment for the Wood-
stock Municipal Landfill
Site

-------
NO.

DATE

AUTHOR

RECIPIENT

70

01/16/98

Flynn, D.;
Phillips,
Lytle,.
Hitchcock,
Blaine &
Huber, LLP

0'Grady, J
U.S. EPA

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

73

02/19/98

Barov, B.,
State of
Illinois/
Office of
the Attorney
General

Furey, E.,
U.S. EPA

74

02/23/98

Wright, J.;
McBride,
Baker &
Coles

Furey, E.,
U.S. EPA

75	02/27/98	Furey, E.,	Wright, J.

U.S. EPA	McBride,

Baker &
Coles

Woodstock Municipal Landfill AR

Update #3
Page 11

TITLE/DESCRIPTION

Letter re: August 1,
1997 Record of Decision
Amendment Petition for
the Woodstock Municipal
Landfill Site

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

Letter Forwarding
Attached December 11,
1997 Circuit Court Order
re: City of Woodstock vs.
Illinois Environmental
Protection Agency

Letter re: Identifica-
tion of ARARs Pertaining
to the Landfill Cap at
the Woodstock municipal
landfill Site w/Attach-
ment

Letter re: Identifica-
tion of ARARs for the
Landfill Cap Component
of the Woodstock Muni-
cipal Landfill Remedy

PAGES
6

8
19

2

3

-------
NO.

DATE

AUTHOR

RECIPIENT
GUIDANCE ADDENDUM

76	07/00/89	U.S. EPA/	U.S. EPA

OSWER

77	03/00/90 U.S. EPA/	U.S. EPA

ERL/ORD

78	08/17/90	Falco, C.,	Bolen, B.,

IEPA	U.S. EPA

79	05/00/91	Eastern	U.S. EPA

Research
Group, Inc.

80	10/00/92	U.S. EPA/	U.S. EPA

OSWER/ORD

Woodstock Municipal Landfill AR

Update #3
Page 12

TITLE/DESCRIPTION	PAGES

Technical Guidance	49

Document: Final Covers

on Hazardous Waste

Landfills and Surface

Impoundments (EPA 530-

SW-89-047)

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 Reguirements
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 INTO THE AR:

DOCUMENT MAY BE VIEWED

AT U.S. EPA REGION

-------
NO.	DATE	AUTHOR

81	09/00/93 U.S. EPA/

ORD

82	05/00/94	U. S. EPA/	U.S. EPA

ORD

83	05/00/94	U.S. EPA/	U.S. EPA

OSWER

RECIPIENT
U.S. EPA

84	10/17/95

Feldman, P.,
U.S. EPA/
OERR

U.S. EPA

Woodstock Municipal Landfill AR

Update #3
Page 13

TITLE/DESCRIPTION	PAGES

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]

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
Implentation; October
16-17 1995)

-------
85	03/00/96 U.S. DOI/	U.S. EPA

Bureau of
Reclamation
and U.S. EPA/

NRMRL

86	09/13/96	Wiedemeier,

T., et al.

87	10/00/96	U.S. EPA/	U.S. EPA

OSWER

88	01/00/97 U.S. EPA

89	11/00/97	U.S. EPA/	U.S. EPA

OSWER

Report: Freeze-Thaw
Cycling and Cold Temper-
ature Effects on Geo-
membrane Sheets and
Seams [FINAL] (R-96-03)

Paper: Overview of the
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)

Final Guidance:
Presumptive Response
Strategy and Ex-Situ
Treatment Technologies
for Contaminated Ground
Water at: CERCLA Sites
(EPA 540-R-96-023;

OSWER Directive 9283.1-
12; PB 963508)

OSWER Directive Class-
ification Numbering
System (DOCUMENTS
INDICATED BY ** ARE
INCORPORATED BY REFERENCE
INTO THE ADMINISTRATIVE
RECORD)

Guidance Document:Use
of Monitored Natural
Attenuation at Superfund,
RCRA Corrective Action,
and Underground Storage
Tank Sites [DRAFT INTERIM
FINAL)(OSWER Directive
9200.4-17)

-------
U.S. ENVIRONMENTAL PROTECTION AGENCY
REMEDIAL ACTION

ADMINISTRATIVE RECORD
FOR

WOODSTOCK MUNICIPAL LANDFILL SITE
WOODSTOCK, ILLINOIS

UPDATE #4
JULY 7, 1998

NO.
1

DATE
00/00/00

AUTHOR

Falco, C.,
IEPA

RECIPIENT

Bolen, W.,
U.S. EPA

08/07/92

Falco, C.,
IEPA

Bolen, W.,
U.S. EPA

09/02/92

Falco, C.,
IEPA

Bolen, W.,
U.S. EPA

09/14/92

Falco, C.,
IEPA

Bolen, W.,
U.S. EPA

10/09/92

Bolen, W.
U.S. EPA

Vagt, P.
Warzyn
Engineering,
Inc.

6	10/30/92	Vagt,, P.,	Bolen, W.,

Warzyn	U.S. EPA

Engineering,

Inc.

TITLE/DESCRIPTION

PAGES

Letter Forwarding	188

Attached Illinois Pollu-
tion Control Board's
Opinion re: 35 IAC,

Subtitle G, Parts 810-
815 (Landfill Regulations)

Letter re: Calculation	2

Errors in the Final
Remedial Investigation
Report for the Woodstock
Municipal Landfill Site

Letter re: IEPA's	2

Comments on the August
1992 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	4

Comments on the September

1992 Draft Feasibility

Study for the Woodstock

Municipal Landfill site

Letter re: Modifications	3

to the Draft Feasibility
Study for the Woodstock
municipal Landfill Site

-------
7	11/16/92

Falco, C.,
IEPA

Bolen, W.,
U.S. EPA

8	11/23/92

9	12/29/92

10	01/25/93

11	01/28/93

12	02/11/93

13	02/16/93

Falco, C.,	Bolen, W.,

IEPA	U.S. EPA

Vagt, P.,	Bolen, W.,

Warzyn	U.S. EPA

Engineering,

Inc.

Bolen, W.,	Addressees

U.S. EPA

Maher, K.,
Cromer,
Eaglesfield
& Maher

Bollo, N.,
U.S. E.P.A

Widman, J.,	Bolen, W.,

Warzyn	U.S. EPA

Engineering,

Inc.

Falco, C.,	Bolen, W.,

IEPA	U.S. EPA

Letter re: IEPA Comments
on the Third Submittal
of the Feasibility Study
for the Woodstock Muni-
cipal Landfill Site

Letter re: IEPA's
Additional Comments on
the Feasibility Study
for the Woodstock Muni-
cipal Landfill Site

Letter re: Warzyn's
Response to IEPA's August
3, 1992 Comments on the
Baseline Risk Assessment
for the Final Remedial
Remedial Investigation
Report for the Woodstock
Municipal Landfill Site

Cover Memorandum Forward-
ing the Feasibility Study
for the Woodstock Muni-
cipal Landfill Site for
Review

Letter re: Maximum
Containment Levels (MCLs)
as ARARs for the Woodstock
Municipal Landfill Site

Letter re: January 1993
Monthly Status Report
for the RI/FS at the
Woodstock Municipal Land-
fill Site

Letter re: IEPA's
Comments on the Revised
Feasibility Study for
the Woodstock Municipal
Landfill Site

-------
14	03/23/93	Bolen, W.,	Addressees

U.S. EPA

15

03/ /93

Falco, C.,
IEPA

Bolen, W.,
U.S. EPA

16

04/08/93

Bolen, W. ,
U.S. EPA

Addressees

17

04/12/93

Bolen, W.,
U.S. EPA

Vagt, P.,
Warzyn
Engineering
Inc.

18

06/17/93

Falco, C.,
IEPA

Bolen, W.,
U.S. EPA

19

06/18/96

Day, S. ,
Conestoga-
Rovers; &
Associates

0'Grady, J.
U.S. EPA

20	07/00/96	Conestoga-	U.S. EPA

Rovers &

Associates

Cover Memorandum
Forwarding the Draft
Proposed Plan for the
Woodstock Municipal Land-
fill Site for Review

Letter re: IEPA's
Comments on the Draft
Proposed Plan for the
Woodstock Municipal Land-
fill Site

Cover Memorandum Forward-
ing the Final Proposed
Plan for the Woodstock
Municipal Landfill Site
for Review

Letter re:(l) Receipt
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

Letter re: IEPA's
Comments on the Draft
Record of Decision for
the Woodstock Municipal
Landfill Site w/ Hand-
written Annotated Copy
of the ROD

Letter Forwarding
Attached Revised Pages
for the Quality Assurance
Project Plan for the
Woodstock Municipal Land-
fill Site

Draft Remedial Design/
Remedial Action Work Plan
for the Woodstock Muni-
cipal Landfill Site

-------
21	07/31/96	Frehner, R.,	0'Grady, J

Conestoga-	U.S. EPA

Rovers &

Associates

22	08/01/96	Wanner, S.,	O'Grady, J

Conestoga-	U.S. EPA

Rovers &

Associates

23	09/09/96	O'Grady, J.,	Frehner, R

U.S. EPA	Conestoga-

Rovers &
Associates

24	02/10/97	Wanner, S.,	O'Grady, J

Conestoga-	U.S. EPA

Rovers &,

Associates

25	03/10/97	Mishra, M.,	O'Grady, J

PRC	U.S. EPA

Environmental
Management,

Inc.

26	04/00/97

Conestoga-
Roveis &
Associates

U.S. EPA

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-
stock Municipal Landfill
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

Remedial Design/Remedial	52

Action Work Plan for the
Woodstock Municipal Land-
fill Site

-------
27	04/03/97	Wanner, S.,	O'Grady, J

Conestoga-	U.S. EPA

Rovers &

Associates

28	04/10/97	Wanner, S.,	O'Grady, J

Conestoga-	U.S. EPA

Rovers &

Associates

29

04/21/97

0'Grady, J.,
U.S. EPA

Frehner, R
Conestoga-
Rovers &
Associates

30

07/08/97

0'Grady, J.,
U.S. EPA

Frehner, R
Conestoga-
Rovers &
Associates

31	07/11/97	Wanner, S.,	O'Grady J.

Conestoga-	U.S. EPA &

Rovers &	G. Ratliff

Associates	IEPA

32	09/04/97 Flynn, D.,	O'Grady,

Phillips,	U.S. EPA

Lytle,

Hitchcock,

Blaine &

Huber, LLP

33	10/08/97

Mishra, M.,
Tetra Tech
EM, Inc.

O'Grady, J
U.S. EPA

Letter re: CRA's
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
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
Restrictions Reguirements
for the Woodstock Muni-
cipal Landfill Site

Letter re: U.S. EPA's
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
1997 Semiannual Monitor-
ing Event at the Wood-
stock Municipal Landfill
Site

Preliminary (30%) Design
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

-------
34

01/06/98

Frehner, R.,
Conestoga-
Rovers &
Associates

0'Grady, J
U.S. EPA

35

01/07/98

U.S. EPA

File

36

03/04/98

Northwest
Court
Reporting
Services,
P.C.

U.S. EPA

37

04/01/98

0'Grady, J.,
U.S. EPA

Frehner, R
Conestoga-
Rovers &
Associates

38	04/07/98	Frehner, R.,	Emeric, N.

Conestoga-	U.S. EPA

Rovers &

Associates

39	04/14/98 Mayka, J. and

W. Carney,
U.S. EPA

U.S. EPA/
Superfund
RPMs

Letter Forwarding
Attached HELP Modeling
Scenarios: (l)Geonet
Drainage Layer and (2)
Fill Drainage Layer
for the Woodstock Muni-
cipal Landfill Site

Hydrologic Evaluation
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,
1998 Public Meeting re:
the Woodstock municipal
Landfill Site

Letter re: U.S. EPA's
Response to (1) City of
Woodstock/AlliedSignal's
August 1997 Petition to
Amend the Record of
Decision and (2) CRA'S
Proposal for a Modified
Cap Design at the
Woodstock Municipal
Landfill Site

Letter re: CRA's
Comments on the Proposed
Plan for the ROD Amend-
ment for the Woodstock
Municipal Landfill Site

Memorandum re: Findings
and Recommendations of
the Working Group
Reviewing Landfill Cover
Reguirements and Decision
making by Region 5
Superfund Program

-------
40	04/20/98	Frehner, R.,	O'Grady, J

Conestoga-	U.S. EPA

Rovers &

Associates

26	04/00/97	Conestoga-	U.S. EPA

Roveis &

Associates

27	04/03/97	Wanner, S.,	O'Grady, J

Conestoga-	U.S. EPA

Rovers &

Associates

28	04/10/97	Wanner, S.,	O'Grady, J

Conestoga-	U.S. EPA

Rovers &

Associates

29

04/21/97

0'Grady, J.,
U.S. EPA

Frehner, R
Conestoga-
Rovers &
Associates

30

07/08/97

0'Grady, J.,
U.S. EPA

Frehner, R
Conestoga-
Rovers &
Associates

Letter re: CRA's Response
to U.S. EPA's April 1,
1998 Letter Concerning
the Proposed Plan for the
ROD Amendment for the
Woodstock Municipal Land-
fill Site

Remedial Design/Remedial
Action Work Plan for the
Woodstock Municipal Land-
fill Site

Letter re: CRA's
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
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
Restrictions Reguirements
for the Woodstock Muni-
cipal Landfill Site

Letter re: U.S. EPA's
Approval of the RD/RA
Work Plan and Quality
Assurance Project Plan
for the Woodstock Muni-
cipal Landfill Site w/
Attached QAPP Signature
Pages

-------
31	07/11/97	Wanner, S.,	O'Grady J.

Conestoga-	U.S. EPA &

Rovers &	G. Ratliff

Associates	IEPA

32

09/04/97

Flynn, D.,
Phillips,
Lytle,
Hitchcock,
Blaine &
Huber, LLP

O'Grady, J
U.S. EPA

33

10/08/97

Mishra, M.,
Tetra Tech
EM, Inc.

O'Grady, J
U.S. EPA

41

05/11/98

Mishra, M.,
Tetra Tech
EM, Inc.

O'Grady, J
U.S. EPA

42

05/20/98

Ratliff, G.,
IEPA

O'Grady, J
U.S. EPA

43

06/00/98

U.S. EPA

File

44

07/01/98

Wanner, S.,
Conestoga-
Rovers &
Associates

O'Grady, J
U.S. EPA &
G. Ratliff
IEPA

Memorandum re: April	58

1997 Semiannual Monitor-
ing Event at 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	5

Technical Review Comments
on the Preliminary (30%)

Remedial Design Report
for the Woodstock Muni-
cipal Landfill Site

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: IEPA's Con-	2

currence with the Proposed
Plan for the ROD Amend-
ment for the Woodstock
Municipal Landfill Site

Guidance: OSWEP 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

-------
07/07/98	Mishra, M.,	O'Grady,

PRC	U.S. EPA

Environmental
Management,

07/07/98	Bolen, W. ,	U.S. EPA

U.S. EPA

Letter re: Cost Update
to the ROD Amendment for
the Woodstock Municipal
Landfill Site

Affidavit re: ARAR
Determination by IEPA
for the Woodstock Muni-
cipal Landfill Site

-------