attachment 4, epa's response to comments on … · comments pertained to the economic...

Attachment 4 EPA's Response to Comments on the EE/CAand the EE/CA Fact Sheet

RESPONSIVENESS SUMiARY

BRRKHMSEELWIEW HARTFORD IANDFILL SUPERRJND SPEE

JSNUAKY 1996

TABLE OF CENTENTS

PREFACE

1.0 OVERVIEW OF ALTERNATIVES EVALUATED IN THE EE/CA

2.0 SITE HISTORY AND BACKGROUND ON COMMUNITY INVOLVEMENT AND CONCERNS

2.1 SITE HISTORY

2.2 BACKGROUND ON COMMUNITY INVOLVEMENT AND CONCERNS

3.0 SUMMARY OF COMMENTS RECEIVED DURING THE PUBLIC COMMENT PERIOD AND EPA RESPONSES

ATTACHMENT A - WRITTEN COMMENTS SUBMITTED BY THE PUBLIC.

ATTACHMENT B - COPY OF THE TRANSCRIPT FROM THE PUBLIC HEARING HELD ON JANUARY 11, 1995.

PREFACE

The U.S. Environmental Protection Agency (EPA) held a public comment period from December 15, 1994 through January 30, 1995 to solicit comments on EPA's proposed cleanup plan for the Barkhamsted-New Hartford Landfill Site (the "site") in Barkhamsted, Connecticut. The cleanup plan was proposed after an Engineering Evaluation/Cost Analysis (EE/CA) was developed by O'Brien & Gere Engineers, Inc. for the Potentially Responsible Parties (PRPs) at the site. The EE/CA evaluated various options for addressing site contamination. Based on the EE/CA, EPA identified its preliminary recommendation for a non-time critical removal action (NTCRA) in a Fact Sheet dated December 1994, and issued prior to the start of the public comment period. EPA also presented the key aspects of the proposed plan during a public meeting held on December 14, 1994. On January 11, 1995, EPA held a public hearing to allow verbal comments to be entered into the record. On October 25, 1995, EPA participated in a meeting with the Connecticut Department of Environmental Protection (CT DEP) and the PRPs to listen to and gain a better understanding of the concerns of these interested parties with respect to moving forward with the NTCRA, and to discuss recent State legislation pertaining to financing of the cleanup. This meeting was held because it had come to EPA's attention over the preceding months that comments previously received from the PRPs during the public comment period had changed in light of the available funding.

The purpose of this Responsiveness Summary is to document EPA's responses to the questions and comments raised during the public comment period. EPA considered all of the comments summarized in this document prior to its decision on this action.

This Responsiveness Summary is organized into the following sections:

Section I - Overview of Alternatives Evaluated in the EE/CA - This section briefly outlines the remedial alternatives evaluated in the EE/CA, including EPA's preferred alternative.

Section II - Site History and Background on Community Involvement and Concerns - This section provides a brief history of the site and an overview of community interests and concerns regarding the site.

Section TTT - Summary of Comments Received During the Public Comment Period And EPA Responses - This section summarizes and provides EPA's responses to the verbal and written comments received from the public during the comment period. In addition, two attachments are included with this Responsiveness Summary.

Attachment A contains the written comments submitted by the public. Attachment B contains a copy of the transcript from the public hearing held on January 11, 1995 in Southington, Connecticut.

Responsiveness Summary

1.0. OVERVIEW OF AIMENATIVES EVALUATED IN THE EE/CA

Using the information gathered during the remedial investigation and the baseline human health and ecological risk assessment, EPA identified several response objectives for the NTCRA at the Barkhamsted-New Hartford Landfill.

The primary objective of the response action was to minimize future potential impacts to human health and the environment by controlling the contaminated landfill source area. The secondary objective was to minimize the migration of any contaminated groundwater, sediments and soils away from the landfill. These objectives sought to:

1. Reduce to a minimum the amount of precipitation allowed to infiltrate through the unsaturated waste column and contaminate the ground water;

2. Prevent direct contact with landfill contaminants by maintaining a physical barrier;

3. Control landfill gas to prevent fire or explosion hazards;

4. Collect contaminated ground water at the limits of the buried waste to the extent practical;

5. Control surface water runoff to minimize cap erosion.

Based on the above objectives, the EE/CA developed and evaluated potential cleanup alternatives to address the source of site contamination. EPA selected a preferred alternative by considering the extent to which each alternative would meet the response objectives. The preferred alternative included the following features:

Landfill cap - Constructing a multi-layered cap over the landfill surface to minimize the infiltration of water into the waste. The preferred cap consists of a geosynthetic clay liner (GCL) overlaid with a cap of synthetic material.

Leachate collection and treatment - Installing a leachate collection trench in the vicinity of the existing leachate streams, primarily on the north side of the landfill. The leachate would be stored in a collection vessel prior to treatment off-site at a licensed waste handling facility.

Landfill gas collection and treatment - Including a landfill gas removal system as part of the landfill cap.

Institutional controls - Establishing institutional controls such as deed restrictions, limiting site access, and continuing monitoring and cap maintenance.


The estimated costs for the preferred cleanup alternative described above fell in a range of 7 to 9 million dollars. The estimated time for construction of the cap and estimated annual operation and maintenance costs were not known but were to be explored during design of the cap. This alternative was selected because it achieved the best balance among the criteria used by the EPA to evaluate cleanup options. The other cleanup alternatives considered in the EE/CA varied from the preferred alternative only with regard to site grading and landfill cap design. These alternatives are described in the December 1994 fact sheet and are discussed in detail in the EE/CA.

2.0 SITE HISTORY AND BACKGROUND OK COMJNITY INVOLVEMENT AND CONCERNS

2.1 SITE HISTORY

The towns of Barkhamsted, New Hartford, Winchester, and Colebrook formed Regional Refuse Disposal District (RRDD) #1 in May 1970 to create a common waste disposal site. RRDD #1 is owned and operated by those four towns and has a board of directors and an administrator to oversee its operations. After receiving a Connecticut Department of Environmental Protection (CT DEP) solid waste permit in September 1972, the towns initiated municipal landfill and recycling operations in 1974.

The landfill accepted municipal solid waste and industrial waste including oily metal grindings, sludges, and liquid chemical waste. A barrel crushing operation for metals reclamation was also located at the landfill. The landfill ceased accepting waste for disposal in 1993. A bulky waste transfer station is currently located and municipal recycling conducted on-site.

In 1980, CT DEP conducted a site inspection of the site, and subsequently identified the site to EPA. EPA conducted a preliminary assessment of the site in 1981. Further investigation was recommended because of the potential nature of wastes disposed of in the landfill. During a second CT DEP inspection in 1983, leaking drums containing hazardous solvents were observed. The Farmington Valley Health Department conducted tests at the site in late 1982, and shortly thereafter, in early 1983, ordered that an on-site well which served the landfill office be shut down due to contamination. Analytical testing conducted by RRDD #1 in 1986 and 1987 revealed volatile organic compounds (VCCs) in groundwater from both shallow and deep on-site wells.

In 1987, further site inspections conducted by EPA found VOCs in on-site groundwater and landfill leachate discharging into the unnamed brook to the west of the site. In addition, heavy metals were found in oily metal grindings that were disposed of in the landfill. In June 1988, EPA proposed the site for the National Priorities List, a list of the most serious hazardous waste sites that warrant federal action. The site was added to the list in October 1989.


In 1991,a group of parties potentially responsible for the contamination at the site agreed to conduct the site investigations. A legal agreement was signed which specified how the investigations would be carried out under EPA's oversight.

The settling parties began investigating the contamination at the site in December 1991. The investigations included air, soil, groundwater, leachate, stream and sediment sampling and analysis. The initial results of the investigation indicated that the landfill was a continuing source of VOC contamination in both on-site and off-site groundwater, and to a lesser extent, downstream surface water and sediment. However, domestic supply wells in the vicinity of the site have not been affected by the site-related contaminants. The studies indicated the potential for future impact to these wells if leachate continues to enter groundwater which eventually migrates downgradient of the site.

Additional site investigations are anticipated to further characterize the nature and extent of contamination on- and off-site. Monitoring of ground water, surface water and sediment, and leachate began in August 1995. The monitoring will assess the long term changes in the nature, extent, and quantity of contamination both on- and off-site.

2.2 BACN3CUND CN COMJNITY INVOLVEMENT AND CONCERNS

EPA's cammunity relations program for the Barkhamsted-New Hartford Landfill began with community interviews in December 1991, which coincided with the start of site field investigations being conducted by the PRP Group. EPA completed a Community Relations Plan for the site in April 1992. This plan, which was based on those interviews and on EPA site files and newsclippings, provides guidance for ensuring that future community relations activities at the site will be geared toward meeting the specific concerns of residents and officials of the four communities which the landfill serviced.

EPA's Technical Assistance Grant program provides grants with which local groups affected by Superfund sites can obtain independent assistance in understanding cleanup activities at the site. EPA-New England recently awarded a technical assistance grant at the Barkhamsted-New Hartford Landfill Superfund Site to the Farmington River Watershed Association, Simsbury, CT.

EPA has prepared an Administrative Record to document the information used by the Agency to propose the cleanup decision for the site. These documents have been and are available for public review at EPA's offices in Boston, MA and at the site repository at the Beardsley & Memorial Library in Winsted, CT. EPA held a public meeting on December 14, 1994 to provide information and obtain public input on the proposed plan. EPA conducted a public comment period from December 15, 1994 through January 30, 1995. A public hearing was conducted on January 11, 1995 to formally receive verbal public comments. On October 25, 1995, EPA participated in a meeting with CT DEP and the PRPs to listen to and gain a better understanding of the concerns of these interested parties


with respect to moving forward with the NTCRA, and to discuss recent State legislation pertaining to financing of the cleanup. Written comments are included in Attachment A of this Responsiveness Summary and the transcript of the public hearing is included in Attachment B.

Comments received during the public comment period focused on apparent deficiencies in the Risk Evaluation section of the EE/CA, and the appropriateness of considering present and future risks equally. Other comments pertained to the economic viability of certain companies affected by the cleanup, and the fairness of the allocation of liability and the Super-fund Law. This summary responds to the comments received during the public comment period on the proposed plan and the supporting analysis and information contained in the Administrative Record.

3.0 SUM1ARY OF (rfHENTS RECEIVED DURING THE PUBLIC CCTMENr PERIOD AND EPA RESPONSES

Written and verbal comments were submitted to EPA during the public comment period. A total of 31 commenters responded to EPA's proposed cleanup plan, two of whom responded both in writing and at the public hearing. The comments are summarized and presented below with EPA's responses. Many of the comments made by individual parties concerned the same issues and are summarized together in this responsiveness summary.

Comment 1: Several commenters raised concerns about the risk assessment prepared prior to EPA's cleanup proposal. The commenters maintain that the EE/CA presents the environmental and public health "threat" posed by the Landfill as hypothetical and that there is no present, actual threat to human health and safety as a result of landfill contamination. One commenter stated that the EE/CA's qualitative risk evaluation is predicated upon fundamentally flawed assumptions, and that there is no evidence in the EE/CA, or in any of the other documents, establishing that there will ever be a "future residential user" of contaminated groundwater facing the hypothetical cancer risk. One commenter also maintained that the risk evaluation is hampered by inadequate data.

Response: For risk assessment purposes, EPA considers current and future land uses in the vicinity of a Superfund site. It is EPA policy to use a residential scenario, as well as other appropriate scenarios, for conducting baseline risk assessments at Superfund sites if residences exist nearby the site. A ground water users survey has been conducted and the results will be presented in the final Remedial Investigation report. EPA will gather additional evidence pertaining to the use and value of ground water in the area. This information will include the likelihood and identification of future drinking water use, and other current or reasonable expected ground water use(s) in the area.

Comment 2: There is no evaluation regarding the probability of changes in environmental conditions that might result in off-site transport in excess of


permissible levels. No evidence is presented as to when the drinking water wells in the vicinity of the landfill will become contaminated.

Response: The draft Remedial Investigation report contains sections on the hydrogeology of the site and contaminant nature, fate and transport. These sections present a characterization of the site geology and the potential for contaminants from the site to enter the ground water system and migrate to potential receptors. Additional site investigations are anticipated to further characterize the nature and extent of contamination on- and off-site. Monitoring of ground water, surface water and sediment, and leachate began last summer, and will be summarized in an addendum to the RI. The purpose of the monitoring is to assess the long term changes in the nature, extent, and quantity of contamination at and emanating from the landfill which may be affected by seasonal and climatological influences. Modelling may be conducted to predict the fate and transport of contaminants at the site and their potential to impact drinking water wells.

Garment 3: One canmenter asked whether the federal government should consider imposing a "remedy" that will cause actual and direct harm in order to address what the EE/CA characterizes as a "potential" environmental problem. Another canmenter stated that "It appears EPA is more concerned about the potential threat posed by the landfill to the environment than about the actual harm the proposed remedy will do to the residents and businesses of this region."

Response: In accordance with the Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCIA), as amended by the Superfund Amendments and Reauthorization Act of 1986 (SARA), and the National Oil and Hazardous Substances Pollution Contingency Plan (NCP), the lead agency at the site is responsible for protecting human health and the environment through timely and effective remediation at Superfund sites. To this end, it is the EPA's responsibility and policy to analyze and evaluate current threats as well as future foreseeable threats to human health and the environment. At this site, a NTCRA is proposed to address threats to public health, welfare, or the environment. An EE/CA was prepared to identify the objectives of the NTCRA and to analyze the various alternatives potentially used to satisfy these objectives with respect to cost, effectiveness and implementability. Thus, cost is a factor which was considered in the selection of a preferred alternative; however, the "actual and direct harm" of cleanup costs to businesses and residents is not the only factor evaluated with respect to these alternatives.

The State of Connecticut Substitute Senate Bill No. 938, Special Act No. 95-20 entitled "An Act Concerning the Authorization of Bonds of the State for Capital Improvements and Other Purposes", provides, among other things, for the availability of four million dollars in bond funding in fiscal year 19951996 and an additional four million dollars in fiscal year 1996-1997. This funding is being provided by the State, through CT DEP, for remedial action at the Barkhamsted-New Hartford Landfill.


The feasibility study which will be completed for the management of migration at the site will contain a detailed comparative analysis to evaluate remedial alternatives based on nine evaluation criteria, including overall protection of human health and the environment, compliance with applicable or relevant and appropriate requirements (ARARs), and long-term effectiveness and permanence. EPA has considered the comments of the State and community in its decision regarding the NTORA and will do so in its decision regarding the appropriate remedial action to be documented in the Record of Decision.

Comment 4: Several commenters believed that the EPA should delete the landfill from the NPL and proceed with closure under RCRA Subtitle D. These conmenters believed that the facility should be re-evaluated and re-scored based upon the new data collected, before any additional action is taken.

Response: In June 1988 EPA proposed the site for the National Priorities List, and the site was added to the list in October 1989 after consideration of public comment to the proposal. EPA does not intend to re-score the site as EPA does not re-score sites based upon new data collected after placement of a site on the National Priorities List. Pursuant to Section 105 of CERdA, the site was listed on the NPL according to certain criteria relating to threats to public health, welfare or the environment. Under Section 300.425(e) of the NCP, a Superfund site cannot be deleted from the NPL or recategorized until EPA has determined that no further response is appropriate. In making a determination to delete a site from the NPL, EPA is required to consider whether the responsible parties or other persons have implemented all appropriate response actions required, all appropriate Fund-financed response under CERCLA has been implemented, no further response action by responsible parties is appropriate, and the remedial investigation has shown that the release poses no significant threat to public health or the environment and, therefore, taking of remedial measures is not appropriate.

With respect to closure under RCRA Subtitle D, the feasibility study to be at the site will contain a detailed comparative analysis to evaluate remedial alternatives based on nine evaluation criteria, including overall protection of human health and the environment, compliance with applicable or relevant and appropriate requirements (ARARs), and long-term effectiveness and permanence. EPA expects that a full range of remedial alternatives will be evaluated in the feasibility study, and that a preferred remedial alternative will be proposed based on the comparative analysis, including ARARs compliance.

Comment 5: The ground water section lacks critical information regarding transport rates and hydraulic conductivity.

Response: The EE/CA (see Section 2.3.4, entitled Ground Water) did not contain all of the information which has been generated during the remedial investigation of the site. The EE//CA was prepare to address the source of contamination. Site characterization results, including complete information on transport rates and hydraulic conductivity, will be described in the RI/FS


report. EPA will propose a cleanup plan for the management of migration at the site after this report has been completed. EPA estimates that this will occur in the summer of 1996.

Gconent 6: "The removal action objectives ("RAOs") are fundamentally flawed. The RAOs are designed to 'minimize future potential impacts from the landfill to the groundwater aquifer, the community, and the Farmington River valley.' EE/CA Section 3.2 at 29. The evidence in the record, however, is that the Landfill has had a minimal impact on the groundwater aquifer beyond the landfill boundary (see EE/CA Section 2.4 Risk evaluation), and no environmental impact on the community or on the Farmington River valley."

Response: The RAOs were developed to help define the scope of the NTCRA. The RAOs were established in part to ensure that there is no impact on public health, welfare or the environment in the future, and are based upon expected future events, not only current situations. In addition, as discussed above, EPA is required to evaluate all potential future exposures, not just the current exposures/impacts. For risk assessment purposes, EPA considers current and future land uses in the vicinity of a Superfund site.

The groundwater located off-site and downgradient of the landfill is currently classified by the State as GA. This designation applies to groundwater within the area of influence of private and potential public water supply wells. Class GA ground water is presumed suitable for direct human consumption without treatment. The State's goal is to maintain the drinking water quality class GA standard. Evidence indicates the exceedance of federal drinking water standards beyond the landfill boundary, and that groundwater discharges to the West Branch Farmington River floodplain. Additional study is therefore necessary to further clarify the current and potential impact of any groundwater plume and to otherwise fully characterize the nature and rate of contaminated groundwater movement and the landfill's effects upon the ecosystem.

Ocmnent 7: Several oommenters noted that although the EE/CA characterizes the landfill cap, leachate collection, and groundwater infiltration control measures set forth in EE/CA Section 5.3.3 as a removal action, such measures are in fact more accurately characterized as a remedial action. See 42 U.S.C. Section 9601(24); 40 CFR 300.5.

Response: CERCLA provides for two response authorities: removal and remedial. Section 101(23) of CERCLA defines removal actions to include "the cleanup or removal of released hazardous substances from the environment, such actions as may necessarily be taken in the event of the threat of release of hazardous substances into the environment, such actions as may be necessary to monitor, assess, and evaluate the release or threat of release of hazardous substances, the disposal of removed material, or the taking of such other actions as may be necessary to prevent, minimize, or mitigate damage to the public health or welfare or to the environment, which may otherwise result from a release or threat of release." NTCRAs (one type of removal action) can range in scope

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fron small-scale, lew-cost actions to complex multi-media response actions; however, they remain removal actions and are subject to the statutory and regulatory requirements regarding removals, and are not remedial actions.

Section 101(24) of CERCXA defines remedial actions as "those actions consistent with permanent remedy taken instead of or in addition to removal actions in the event of a release or threatened release of a hazardous substance into the environment, to prevent or minimize the release of hazardous substances so that they do not migrate to cause substantial danger to the present of future public health or welfare or the environment."

Comment 8: Several commenters noted that it appears that the EE/CA's proposed response action violates the cost-effectiveness requirements of 42 U.S.C. Section 9621(a). Furthermore, these commenters state that it appears that the EE/CA analysis did not incorporate any of the 42 U.S.C. Section 9621(b) (1) factors that must be considered in assessing proposed remedial actions.

Response: As noted above, a OTCRA is a removal action and not a remedial action. NTCRAs are not required to be analyzed with respect to the nine criteria specified in the NCP (Section 300.430(e)(9)(iii)) for remedial actions. These criteria are: overall protection of human health and the environment; compliance with ARARs; long-term effectiveness and permanence; reduction of toxicity, mobility, or volume; short-term effectiveness; implementability; cost; State acceptance; and community acceptance. Those criteria only apply to evaluation of alternatives compared in the RI/FS and remedial actions proposed in Records of Decision. The criteria that apply to NTCRA's are: effectiveness, implementability and cost; however, the components of these criteria are similar to the nine criteria mentioned above. These criteria, and the analysis of each alternative proposed for this NTCRA, are presented in detail in the EE/CA.

Comment 9: One commenter stated that, given the State of Connecticut's role in the creation and operation of the landfill, the State and EPA should be exploring a cooperative agreement arrangement under 42 U.S.C. Section 9604(c) (3) to provide Superfund monies for site cleanup, and that the State should be responsible for the cost of cleanup. Another commenter suggested that any cleanup activity should be deferred until after Governor Rowland and the Legislature have the opportunity to fund the 1989 Bill authorizing State funding of Superfund cleanups. Commenters stated that the state and federal agencies should be responsible for the cost of cleanup.

Response; CERdA imposes liability when there has been a release or threat of a release of a hazardous substance at a facility which causes the incurring of response costs. This liability attaches to owners and operators of the facility, to owners and operators at the time of disposal of hazardous substances, and to generators and transporters of the hazardous substances (see Section 107 of CERdA). EPA issued general notice letters to those potentially liable parties believed to fall within this liability scheme. Rather than depleting the Superfund Trust Fund, it is generally EPA's strong


preference, and legal obligation, to pursue the parties responsible for contamination and require them to investigate and cleanup Superfund sites. When PRPs agree to conduct the cleanup, they are allowed to hire their own contractors. PRP cleanup is done under EPA's close oversight to ensure that proper conduct of the remedial action takes place. EPA and CT DEP receive and review reports generated by the PRPs.

With respect to this site, the State of Connecticut Substitute Senate Bill No. 938, Special Act No. 95-20 entitled "An Act Concerning the Authorization of Bonds of the State for Capital Improvements and Other Purposes", provides for the availability of four million dollars in bond funding in fiscal year 19951996 and an additional four million dollars in fiscal year 1996-1997. This funding is being provided by the State, through CT DEP, for remedial action at the Barkhamsted-New Hartford Landfill. The State considers the remediation of the landfill to be a priority, as evidenced by the amount of funding that has been made available. EPA anticipates entering into an agreement with the State to accomplish the removal action, pursuant to which the State will oversee an enforcement-lead NTCRA through a Consent Order with one of the PRPs.

Ccmnent 10: One commenter was concerned about the appropriate use of the Site after cleanup.

Response: During the design period for the NTCRA, and development of the feasibility study, EPA will look at various land use alternatives for the Site. The alternative chosen will be used to determine the cleanup levels of the various contaminants and potential deed restrictions to be placed on the Site. EPA plans to continue to work with the community as specified in the Community Relations Plan to ensure that community concerns are addressed. In addition, the public will have the opportunity to review and comment on the proposed plan to be developed upon completion of the RI/FS.

Ccranent 11: The EE/CA indicates that there will be generation of gas and leachate from the landfill. One commenter inquired as to how these discharges will be vented ~r collected, and what controls will be placed upon them.

Response: There is a requirement in the EE/CA that all landfill gas and leachate be collected. During the design period for the NTCRA, the amount of gas that is anticipated to be generated will be calculated, and the State requirements for air emissions will be applied. This will determine the need for, and type of treatment system for, the gas. The leachate will be collected by extraction wells or trenches, and the treatment system will also be determined during the design phase of the NTCRA. A provision is made for the treatment of leachate off-site.

Comnent 12: One commenter noted that the description of the Leachate Collection and Recovery System does not address how and whether the Farmington River and watershed area will be protected from further pollution.

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Response: The leachate aollection system is proposed to prevent, to the extent practicable, the migration of contaminated ground water and leachate beyond the boundary of compliance, and to prevent, to the extent practicable, the generation of leachate seeps and the migration of landfill impacted surface water into the Farmington River valley watershed and other surrounding surface water bodies. Containment actions and technologies were evaluated in the EE/CA to address the buried wastes and leachate. The EE/CA proposed that containment will be accomplished by constructing a leachate collection system and a multi-layered cap that miniitiizes the infiltration of water into the waste. The system will be designed during the OTCRA to ensure protection from further pollution.

dement 13: On commenter stated that whatever remediation action is ultimately decided on, the continued operation of the existing transfer station and recycling center at RRDD#1 should be made a priority during the operation.

Response: EPA has no intention of interfering with the continued operations of the transfer station as long as those operations do not interfere with the selected cleanup plan or threaten public health or welfare or the environment.

Ccinnent 14: One commenter suggested that permanent provision should be made in the remedy for a water supply for the Town's garage. Water sufficient for drinking, hand-washing, lavatory, and for washing vehicles, should be provided.

Response: EPA will take this into consideration during the feasibility study to be completed for the management of migration at the site.

Comment 15: One commenter asked how EPA can expect the public to go through the volumes of material at the library and come to some sort of decision as to what would be best. This commenter also requested itemized accounts of how the "approximate" figures are going to be spent.

Response: EPA acknowledges that there is a significant amount of information that has been generated regarding this site. The intent of the December 1994 fact sheet, and the public meeting that was held on December 14, 1994, were to very simply summarize the information contained in the repository.

EPA's Technical Assistance Grant program provides grants with which local groups affected by Superfund sites can obtain independent assistance in understanding clean-up activities at the site. EPA-New England recently awarded a technical assistance grant at the Barkhamsted-New Hartford Landfill Superfund Site to the Farmington River Watershed Association, Simsbury, CT. Specific cost estimates within each alternative are contained in Appendix B of the EE/CA.

Comment 16: One ccmmenter questioned how the GCL/VLDPE liner (Alternative A) would be joined or integrated into the silty sand bedding layer/VLDPE liner (Alternative D). In addition, depending on how the two designs interface,

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there was concern that the Alternative D bedding layer could become saturated from leakage occurring along the top liner or interface. A question arises as to whether the integrity of the Alternative D cap would be compromised if this condition were to occur. A description and depiction of the interface between Alternative A and D would help resolve this issue.

Response: Details describing the transition area between the top surface and the side slope will be generated during design of the NICRA. The geosynthetic clay liner (GCL) will be extended somewhat over the silty sand or sandy silt layer towards the side slope. The drainage layer constructed over the textured geomembrane on the sideslopes will effectively minimize any leakage.

Ocnment 17: A commenter stated that once the cap is installed as proposed, existing leachate seeps along the slopes would continue to generate leachate for an indeterminate period of time. Alternative D will be designed to allow this leachate to migrate through the gas vent layer to the interception/collection system. A question arises as to whether leachate or condensate from the landfill could come into contact with and saturate the adjacent silty sand bedding layer. The commenter also asked if this condition create a failure potential along the sideslopes.

Response: Leachate seeps along the sideslopes generally occur intermittently during and/or after rainstorm events. Once the cap is installed to prevent rainwater infiltration, the leachate seeps will disappear. If there are still any continuous leachate seeps due to leachate mounding within the landfill, the leachate mounding will be controlled and collected using leachate collection systems. The leachate collection systems are designed to lower the leachate/groundwater level beneath the waste, so that saturation of the final cover will be prevented. In addition, the geosynthetic filter fabric that is proposed to be placed between the waste and the gas vent layer is designed to divert water.

Comment 18: A commenter described that the 6-inch silty sand layer to be used as a stable soil bedding material for cap stability does not appear to have widespread application, at least in Connecticut. They noted it would be helpful if further documentation would be supplied as to how this 6-inch bedding layer will minimize shear and slope failure.

Response: The minimum 6-inch silty or sandy silt layer that is proposed as a stable soil bedding material on steep sideslopes for cap stability (especially for critical interface between the geomembrane and soils) will provide better long-term slope protection than the use of GCL or compacted clay. The GCL (or compacted clay) may cause a slope failure due to insufficient frictional resistance. The textured geomembrane and a relatively low-permeable soil layer such as silty sand and sandy silt on steep sideslopes function as a good moisture barrier with stability where more runoff than infiltration is expected. Details of the material to be used for the stability of geomembrane interfaces will be determined during the design.

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Ocmnent 19: A cxronenter indicated that none of the four alternatives depicted in Figures 11 - 14 of the EE/CA show the approximately 24-inches of cover material placed on the landfill as part of state closure requirements nor is it mentioned in the text. This cover meets certain regulatory requirements for grain size and permeability. There should be some discussion on whether the existing soil cover is suitable to leave in place and would not be an issue affecting slope stability. Another issue that should be discussed is whether the existing cover will restrict landfill gasses from migrating into the gas vent layer.

Response: Both of these concerns will be considered and addressed during design of the OTCRA.

Ccnment 20: A commenter noi-̂ d that pages 55 and 56 of the EE/CA indicate that the HELP model simulations show a greater than 99.9 percent reduction in water infiltration into the landfill for a cap consisting of GCL under a flexible membrane hydraulic barrier. It appears that these simulations apply only to Alternative A and not Alternatives B through D. It would be helpful to quantify the effectiveness of Alternative D using the HELP model because the area! extent of Alternative D could be significant.

Response: This concern will be considered and addressed during design of the NTCRA.

Odnnent 21: A commenter mentioned that the Alternative D capping design was evaluated for slopes no greater than 3H:1V. The commenter inquired as to whether provisions to regrade slopes found to exceed 3H:1V were made.

Response: Maximum slopes should not exceed 3H:1V due to cover stability considerations and to assure safe operation of maintenance equipment. If existing grades are found to exceed IV: 3H, the final grades will be regraded to meet maximum slopes of IV: 3H.

Comment 22: A commenter stated that the proposed landfill cap will be required to incorporate an active gas collection system with air pollution controls because potential emissions at this landfill exceed 5 tons/year as determined by O'Brien & Gere.

Response: During the design period, the amount of gas that is anticipated to be generated will be calculated, and the State requirements for air emissions apply. This will determine the need for, and type of treatment system for the gas.

Comnent 23: A commenter stated that the EE/CA does not suggest who will pay the $7.5 million for the cap, and that the EE/CA should be put on hold while The Coalition for Superfund Justice's concerns and other concerns are addressed.

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Response: The State of Connecticut Substitute Senate Bill No. 938, Special Act No. 95-20 entitled "An Act Concerning the Authorization of Bonds of the State for Capital Improvements and Other Purposes", provides for the availability of four million dollars in bond funding in fiscal year 1995-1996 and an additional four million dollars in fiscal year 1996-1997. This funding is being provided by the State, through CT DEP, for remedial action at the Barkhamsted-New Hartford Landfill. EPA will oversee completion of the RI/FS and generate a proposed plan for the management of migration component of the site remedy once this study is complete.

rv»iiiiMni 24: Several commenters stated that the costs associated with the proposed action would force small companies out of business. Some commenters are concerned about losing their jobs, consider the Superfund law unfair, and suggest the Superfund law be changed to protect innocent parties and tax everyone fairly. Commenters also urged EPA to offer de minimis settlements to gualifying parties at the site.

Response: An EE/CA was prepared to identify the objectives of the NTCRA and to analyze the various alternatives potentially used to satisfy these objectives with respect to cost, effectiveness and implementability. Thus, cost is a factor which was considered in the selection of a preferred alternative; however, the costs to businesses is not the only factor evaluated with respect to these alternatives. The State of Connecticut Substitute Senate Bill No. 938, Special Act No. 95-20 entitled "An Act Concerning the Authorization of Bonds of the State for Capital Improvements and Other Purposes", provides for the availability of four million dollars in bond funding in fiscal year 19951996 and an additional four million dollars in fiscal year 1996-1997. This funding is being provided by the State, through CT DEP, for remedial action at the Barkhamsted-New Hartford Landfill. EPA has considered the comments of the State and community in its decision regarding the NTCRA and will do so in its decision regarding the appropriate remedial action to be documented in the Record of Decision.

Under Section 122(g) of CERCLA, EPA may settle for a minor amount of response costs at a site with parties who contributed to a facility hazardous substances which are minimal, both in terms of volume and toxicity or other hazardous effects, relative to other hazardous substances. EPA must make certain legal and administrative determinations regarding PRP eligibility for a de minimis settlement. EPA is committed to entering into de minimis settlements vfcerever and whenever possible, and will examine the possibility of a de ™i"JTHi? settlement at this site at an appropriate point in the process.

Comment 25: Commenters inquired how it was determined that certain companies were involved with disposal at the landfill and how EPA compiled their list of potentially responsible parties.

Response: CERCLA imposes liability when there has been a release or threat of a release of a hazardous substance at a facility which causes the incurring of

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response exists. This liability scheme attaches to owners and operators of the facility, to owners and operators at the time of disposal of hazardous substances, and to generators and transporters of the hazardous substances. EPA issued general notice letters to those potentially liable parties believed to fall within this liability scheme.

Gcmnent 26: A commenter asked why the RRDD #1 continued to accept industrial and commercial waste up until 1988.

Response: The RRDD #1 is the most appropriate body to address this issue.

Comment 27: One commenter asked what financial role, past and present, has the transporter of hazardous waste, CT DEP, EPA, and the landfill owners played.

Response: As noted above, transporters of hazardous substances to the landfill and the owner/operator of the landfill fall within the liability scheme established for the site. EPA and CT DEP have incurred response costs due to the agencies' oversight of the RI/FS being conducted by the PRP Group.

Comment 28: A commenter suggested the amount of refuse deposited and the content should be the basis of an individualized billing to user businesses, with the major abusers paying larger amounts than minor ones.

Response: CERCLA liability attaches to owners and operators, to owners and operators at the time of disposal of hazardous substances, and to generators and transporters of the hazardous substances. CERCLA provides for strict joint and several liability.

Comment 29: One commenter questioned why it has taken five years to investigate the causes of the pollution of the landfill.

Response: EPA listed the site on the NFL on October 4, 1989 based upon the results of past investigations conducted by EPA and other parties. A December 1991 Landfill Site Investigation report was prepared in response to CT DEP Order No. 666 issued in 1990 which required RRDD #1 to investigate the site. An Administrative Order on Consent to perform the RI/FS became effective on October 4, 1991. The RI/FS Order was entered into between the U.S., the State, and 24 settling parties. During December 1991 and January 1992, the PRP Group performed a Limited Field Investigation (LFI), pursuant to a LFI Work Plan approved by EPA, in order to produce a focused RI Work Plan. The RI Work Plan was conditionally approved by EPA. A draft Phase IA Site Characterization report was submitted in 1993. Phase IB field work was then conducted and a draft RI report was submitted to EPA for review in April 1994. EPA has reviewed this document. EPA has instructed the PRP Group to begin quarterly sampling of ground water, surface water and sediment, and leachate. EPA approved the Quarterly Sampling Plan in July 1995. Sampling began in August 1995.

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