UNITED STATES ENVIRONMENTA PROTECTIOL N AGENCYPaula Lia Fitzsimmons ME & VT Superfund Section HPS--CAN1 JFK Federal Building Boston, MA 02203 (617) 573-5784 The factual an d legal

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION I

J.F. KENNEDY FEDERAL BUILDING, BOSTON, MASSACHUSETTS 02203-2211

SPECIAL NOTICE LETTER FOR REMEDIAL DESIGN/REMEDIAL ACTION (RD/RA) URGENT LEGAL MATTER — PROMPT REPLY NECESSARY CERTIFIED MAIL; RETURN RECEIPT REQUESTED

May 17, 1989 SDMS DocID 284824

President or General Manager Bryant Computer 123 Main Street Springfield, VT 05156

Re: Old Springfield Landfill, First Operable Unit Remedial Action Springfield, Windsor County, Vermont (the "Site")

Dear Sir:

This letter follows a general notice letter that was issued on April 17, 1987, in connection with the Site. As the listed contact person for the potentially responsible party (PRP) identified above, this letter has been sent to your attention.

This letter serves three basic functions. First, it contains a formal demand for reimbursement of costs that have been incurred, including interest thereon, and that are expected to be incurred, which are subject to interest, in response to the health/environmental concerns at the Site. Second, this letter notifies you that a 60-day period of formal negotiations with the Environmental Protection Agency (EPA) automatically begins with this letter. Third, this letter provides general and Site-

specific information to assist you in these negotiations.

NOTICE OF POTENTIAL LIABILITY

As indicated in the general notice letter previously sent regarding the Site, EPA has information indicating that you may be a PRP as defined at Section 107(a) of the Comprehensive Environmental Response, Compensation, and Liability Act, 42 U.S.C. 9607(a), as amended (CERCLA), with respect to the Site.

SPECIAL NOTICE AND NEGOTIATION MORATORIUM

EPA has determined that use of the Section 122(e) special notice procedures specified in CERCLA will facilitate a settlement between EPA and PRPs for this Site. Therefore, under CERCLA Section 122, this letter triggers a 60-day moratorium on certain EPA response activities at the Site. During this 60-day period, the PRPs, including you, are invited to participate in formal negotiations with EPA. You are also encouraged to voluntarily

negotiate a settlement providing for the PRPs, including yourself, to conduct or finance the response activities required at the Site. The 60-day negotiation period ends on July 21, 1989. The 60-day negotiation moratorium will be extended for an additional 60 days if EPA determines the PRPs have provided EPA with a good faith offer to conduct, or finance the remedial design/remedial action (RD/RA). Should a 120-day negotiation moratorium take place, negotiations will conclude on September 19, 1989. EPA receipt of signed PRP signature pages to the Partial Consent Decree on or before September 19, 1989 will constitute settlement by the PRPs. If settlement is reached between EPA and the PRPs within the 120-day negotiation moratorium, the settlement will generally be embodied in a Partial Consent Decree.

FUTURE RESPONSE ACTIONS

EPA plans to conduct the following response activities at the Site, which will be the subject of the current moratorium period:

1. Design of the Leachate Collection and Groundwater Extraction System;

2. Evaluation and Design of the Groundwater Extraction and Leachate Collection Treatment System;

3. Construction, Operation, and Maintenance;

4. Institutional Controls; and

4. Monitoring.

In addition, certain PRPs are currently undertaking a Focused Feasibility Study pursuant to EPA directions to evaluate alternative source control remedial actions.

SCOPE OF WORK AND DRAFT PARTIAL CONSENT DECREE

A copy of EPA's Record of Decision, the remedial action Scope of Work, and draft Partial Consent Decree are attached. These are provided to assist you and other PRPs in developing a good faith offer for conducting the RD/RA.

GOOD FAITH OFFER

As indicated, the 60-day negotiation moratorium triggered by this letter is extended for 60 additional days if the PRPs submit a good faith offer to EPA. A good faith offer to conduct or finance the RD/RA is a written proposal that demonstrates the

PRPs1 qualifications and willingness to conduct or finance the design, implementation, and monitoring of the remedy. In order for your proposal to be considered a good faith offer, it .roust be in the form of the attached Partial Consent Decree arid Scope of Work, must not be significantly different from EPA's Record of Decision and must include the following elements:

1. A statement of willingness by the PRPs to conduct or finance the RD/RA which is consistent with EPA's Record of Decision as well as Scope of Work and draft Partial Consent Decree ai*d provides a sufficient basis for further negotiations.

2. An element by element response to EPA's Record of Decision, Scope of Work and draft Partial Consent Decree including a response to any other attached documents.

3. A detailed description of the work plan identifying how the PRPs plan to proceed with the work.

4. A demonstration of the PRPs1 technical capability to carry out the RD/RA, including the identification of the firm(s) that may actually conduct the work or a description of the process the PRPs will use to select the firm(s).

5. A demonstration of the PRPs' willingness to finance the response.

6. A statement of willingness by the PRPs to reimburse EPA for costs incurred to date and to be incurred in overseeing the PRPs1 conduct of the RD/RA.

7. The name, address, and phone number of the party or steering committee who will represent the PRPs in negotiations.

8. A description of the PRPs' position on releases from liability and reopeners to liability.

INFORMATION RELEASE

The parties are hereby notified that additional information has been obtained since the previous notice. EPA is providing the following information as an attachment to this letter:

1. An updated list of names and addresses of PRPs to whom this notification is being sent. Inclusion

on, or exclusion from, the list does not constitute a final determination by EPA concerning the liability of any party for the release or threat of release of hazardous substances at the Site.

2. A list of the nature of substances contributed by each PRP. The list is subject to revision based upon new information as, and if, it becomes available.

3. A fact sheet that describes the Site.

DEMAND FOR PAYMENT

With this letter, EPA demands that you reimburse EPA for its costs incurred to date, and encourages you to voluntarily negotiate a Partial Consent Decree in which you and other PRPs agree to perform the RD/RA.

In accordance with CERCLA, EPA already has undertaken certain actions and incurred certain costs in response to conditions at the Site. These response actions include the Remedial Investigation and Feasibility Study. The cost to date of the response actions performed at the Site through EPA funding is approximately $3,000,000. In accordance with Section 107(a) of CERCLA, demand is hereby made for payment of the above amount plus any and all interest recoverable under Section 107 or under any other provisions of law.

As indicated above, EPA anticipates expending additional funds for the Remedial Design and Remedial Action (RD/RA). Whether EPA funds the entire RD/RA, or simply incurs costs by overseeing the parties conducting these response activities, you are potentially liable for these expenditures plus interest.

PRP STEERING COMMITTEE

EPA recommends that all PRPs meet to select a steering committee responsible for representing the group's interests. Establishing a manageable group is critical for successful negotiations with EPA. Alternatively, EPA encourages each PRP to select one person from its company or organization who will represent its interests.

ADMINISTRATIVE RECORD

Pursuant to CERCLA Section 113(k), EPA must establish an administrative record that contains documents that form the basis of EPA's decision on the selection of a response action for a Site. The administrative record files, which contain the documents related to the response action selected for this Site, are available to the public for inspection and comment. The

primary location is the EPA Regional office, 90 Canal Street, Boston, MA. An additional copy is available at the Town of Springfield Public Library, 43 Main Street, Springfield, Vermont 05156.

INITIAL MEETING MTD EPA CONTACT PERSON

You are encouraged to indicate your willingness to participate in future negotiations at the Site by attending the initial negotiations meeting with EPA. The initial meeting will be held on May 31, 1989, at 10 a.m. at the EPA Regional Office, Room 307, JFK Federal Building, Boston, Massachusetts. Otherwise, you have 60 calendar days from May 22, 1989 to provide EPA in writing with a good faith offer demonstrating your willingness to perform the RD/RA. You may respond individually or through a steering committee if such a committee has been formed. If EPA does not receive a timely response, EPA will assume that you do not wish to negotiate a resolution of your liabilities in connection with the response, and that you have declined any involvement in performing the response activities. You may be held liable by EPA under Section 107 of CERCLA for the cost of the response activities EPA performs at the Site and for any damages to natural resources.

Your response to this notice letter should be sent to:

U.S. Environmental Protection Agency Paula Lia Fitzsimmons ME & VT Superfund Section HPS--CAN1 JFK Federal Building Boston, MA 02203 (617) 573-5784

The factual and legal discussions contained in this letter are intended solely for notification and information purposes. They are not intended to be and cannot be relied upon as final EPA positions on any matter set forth herein. EPA will be working in conjuction with the State of Vermont on this matter; however the enclosed documents have not undergone final State review.

If you or your attorney have any questions pertaining to this matter, please direct them to Tim Conway at (617) 565-1132.

Sincerely,

Merrill S. Hohman, Director Waste Management Division

cc: Ken Finkelstein, NOAA William Patterson, DOI Tom Moye, VT DEC Conrad Smith, VT AG Bruce Marshall, EPA Enforcement

ATTACHMENT 1

Record of Decision

Old Springfield Landfill Springfield, Vermont

STATEMENT OF PURPOSE

This Decision Document represents 'the selected remedial action for an operable unit for remediation of groundvater emanating from the seeps and known areas of groundvater contamination at the Old Springfield site 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, the National Contingency Plan (NCP) 40 CFR Part 300 et seq., as amended. The Region I Administrator has been delegated the authority to approve this Record of Decision.

The State of Vermont has concurred on the selected remedy for the operable unit for seeps and limited groundwater and has determined, through a detailed evaluation, that the selected remedy is consistent with its lavs and regulations.

STATEMENT OF BASIS

This decision is based on the administrative record which was developed in accordance with Section 113(k) of CERCLA and which is available for public reviev at the Springfield Town Library in Springfield, Vermont, and the EPA Region I Haste Management Division Record Center in Boston, Massachusetts. The attached . index identifies the items which comprise the administrative record upon which the selection of a remedial action is based.

DESCRIPTION OF THE SELECTED REMEDY

The selected remedy for the Old Springfield Landfill site is a management of migration operable unit for seeps and, to a limited extent, groundvater.

1. Leachate Collection/Groundvater Extraction System

The method for collection of leachate will be an underground system which collects the groundwater at or upgradient of the points of seep emanation. The collection system will collect all ten of the detected seeps on the eastern slope and all four of the detected seeps on the western slope with provisions to collect any other seep should it develop.

In addition to leachate collection, groundvater will be extracted from the sand and gravel zone on the western portion of the site. The collected groundwater and leachate would be conveyed to a wastewater treatment facility.

Detailed criteria will be developed during remedial design to determine the best design and construction techniques for the leachate collection system and the best placement and number of extraction wells.

Underground leachate collection and groundwater extraction are the most effective means of capturing contaminated groundwater after it has migrated away from the source area. The system will allow for the addition of other seeps should there be additional breakouts during the duration of the remedy. Underground collection of leachate will eliminate the pathway for contaminants to volatilize at the seeps by collecting the seeps underground before contact with the air. Leachate collection will also reduce the potential for contaminants to travel into the Black River and Seavers Brook via surface drainage, thus reducing possible contamination of fish in those rivers. A non-continuous underground leachate collection system may be appropriate if it can be demonstrated during design to fulfill the following system objectives:

- collect groundwater on the eastern and western slopes which emanates from the landfill as leachate seeps in order to eliminate the contamination and potential contamination in uncontaminated seeps, migrating to Seavers Brook and the Black River and into the bedrock aquifer;

extract groundwater on the western side of the site in the permeable sand and gravel unit;

eliminate the volatilization and direct contact risk associated with the leachate seeps; and

have collection and extraction systems in place which could be extended should new locations of contaminated leachate or practically extractable and contaminated groundwater be located.

2. Treatment of Groundwater and Leachate

The treatment system for the collected leachate and extracted groundwater will treat the collected leachate and extracted groundwater to meet all federal and state requirements. Treatment will be on-site. However, should the Publicly Owned Treatment Works (POTW) have the ability, capacity, and willingness to treat the extracted groundwater and leachate and meet all federal and state requirements, the collected leachate and

extracted groundwater will be piped to the POTW and treated. If the collected groundwater and leachate is directed to the POTW, it will be pretreated if pretreatroent. is necessary to meet applicable standards, attain surface water quality goals and maintain effective POTW operations. If a demonstration of ability, capacity and willingness is not made, the treatment system will remain onsite.

The Town of Springfield has demonstrated the willingness and capacity to treat the collected leachate and extracted groundwater at the POTW, and has had a review of the system to evaluate if the system has the ability to handle the wastes. This initial evaluation indicates that the POTW may have the ability to treat the wastes. Samples of the collected leachate and extracted groundwater will be bench scale tested during design to ensure effectiveness.

3. Institutional Controls

The selected remedy includes restricting the use of groundwater where it may exceed Maximum Contaminant Levels (MCLs). EPA recommends to the State and Town of Springfield that they implement and enforce ordinance 88-2 passed by the Town of Springfield as an institutional control. Specifically, EPA recommends a prohibition on groundwater use in the area bounded by Route 11 on the east, Mr. Curt in'is present property boundary on the south, Seavers Brook Road on the west and Mr. Curtin's present property boundary on the north until a time when groundwater levels reach MCLs. The ordinance is attached as Exhibit 1.

4. Monitoring

Monitoring of environmental media will be conducted for thirty (30) years to monitor effectiveness of the remedy and to identify any further impacts to human health and the environment. Additionally, as required by CERCLA at sites where any hazardous substances, pollutants or contaminants remain, a review of the site will occur every five (5) years.

5. Additional Studies

Additional studies will be conducted to determine the feasibility of isolating waste materials from groundwater through diverting

groundwater flow around waste materials, creating physical

barriers to separate waste materials from groundwater, landfilling of waste materials in a Hazardous and Solid Waste Amendments (HSWA) landfill, or other appropriate technologies. The additional studies will include but not be limited to:

1) and evaluation of the feasibility, effectiveness, and cost of isolating wastes from groundvater, including a detailed evaluation of:

a. an upgradient, permeable vertical groundwater diversion structure similar in function to a french drain;

b. physical barriers, such as a slurry vail, that separate waste material from groundwater and/or depress the water table to minimize contact between waste and groundwater;

c. a means of lowering the water table in areas of waste disposal to eliminate or minimize contact between waste and groundwater;

d. removing the waste, including that waste in contact with groundwater, for disposal in a HSWA landfill;

e. removing the waste, including that waste in contact with groundwater, for treatment by incineration or vitrification;

f. other means of isolating waste materials from groundwater; and

g. combinations of the above.

2) a quantitative determination of the amount of infiltration and flow contacting buried waste from vertical infiltration and lateral groundwater flow. For each of the evaluations conducted in 1) above, quantitatively compare the amounts of infiltration and groundwater flow contacting waste through

vertical infiltration and lateral groundwater flow before and after remedy implementation; and

3) an identification and characterization of outlying areas of potential contamination which may have escaped detection in earlier investigatory work including the western slope area between Seavers Brook Road and Will Dean Road and an area on the southwestern portion of the site near Will Dean Road, as indicated by the magnetic anomaly in Figure 3-3 of the Supplemental Remedial Investigation, to determine if there are additional source of contamination. If additional contamination is found, it will be remediated as part of the source control operable unit, or taken offsite for disposal in accordance with EPA's offsite policy.

DECLARATION

The selected remedy is protective of human health and the environment, attains Federal and State requirements that are applicable or relevant and appropriate, and is cost-effective. This remedy utilizes permanent solutions and alternative treatment technologies to the maximum extent practicable for this operable unit. Treatment of leachate and contaminated groundvater will occur at the POTW or onsite and will be the maximum extent to which treatment is practicable.

*i Date Michael R. Deland

Regional Administrator

OLD SPRINGFIELD LANDFILL RECORD OF DECISION TABLE OF CONTENTS

Contents Paae Number

I. SITE NAME 1

II. SITE HISTORY AND ENFORCEMENT ACTIVITIES 3 A. Response History 3 B. Enforcement History 4 C. Community Relations 4

IV. SCOPE AND ROLE OF RESPONSE ACTION 5

V. ' SITE CHARACTERISTICS 6 A. Hydrogeology/Groundwater 6 B. Soil 8

VI. SUMMARY OF SITE RISKS 8

VII. DOCUMENTATION OF SIGNIFICANT CHANGES 11

VIII.DEVELOPMENT AND SCREENING OF ALTERNATIVES 12 A. Statutory Requirements/Response Objectives 12 B. Technology and Alternative Development and

Screening 14

IX. DESCRIPTION /SUMMARY OF THE DETAILED AND COMPARATIVE ANALYSIS OF ALTERNATIVES 15

X. THE SELECTED REMEDY 17 A. Description of the Selected Remedy 17 B. Estimated Remedial Schedule ' 22 C. Rationale for Selection/Points of Compliance .... 22

XI. STATUTORY DETERMINATIONS 26 A. The Selected Remedy is Protective of Human Health

and the Environment 26 B. The Selected Remedy Attains ARARs 26 C. The Selected Remedial Action is Cost Effective ... 27 D. The Selected Remedy Utilizes Permanent Solutions

and Alternative Treatment Technologies or Resource Recovery Technologies to the Maximum Extent Practicable 28

E. The Selected Remedy Satisfies the Preference for Treatment as a Principal Element ..... ^ .... 28

XII. STATE ROLE 28

Old Springfield Landfill Site Record of Decision Summary

LIST OF FIGURES

Fiure

Figure 1. Site Location ................... 2 Figure 2. Monitoring Well Locations ............. 7 Figure 3. Waste Areas .................... 9

EXHIBIT

Town of Springfield Ordinance 88-2 ......... Exhibit 1 Letter from Town of Springfield - POTW Use ...... Exhibit 2

APPENDICES

Responsiveness Summary ............... Appendix A Administrative Record Index ............. Appendix B State Concurrence Letter ............. . . Appendix C

ATTACHMENT

Monitoring Well/Leachate Seep Data ......... Attachment 1 Soil Data ..................... Attachment 2 Contaminants of Concern .............. Attachment 3 Management of Migration .............. Attachment 4

ROD DECISION SUMMARY page 1 Old Springfield Landfill

I. SITE NAME: Old Springfield Landfill LOCATION: Springfield, Vermont DESCRIPTION

The 27-acre Old Springfield Landfill site, is located approximately one mile south-west of the city center in Springfield, Windsor County, Vermont (See Figure 1). The site is situated on an upland terrace with slopes that descend steeply to the north, east, and west. Seavers Brook runs west of the site and the Black River runs east of the site. Seavers Brook flows northward until it reaches the Black River, which flows to the south and empties into the Connecticut River.

The Town of Springfield has a population of 10,180, according to the 1980 National Census. The villages of Goulds Mill and Hardscrabble Corner are located within a one-mile radius of the site. Approximately 60 people resided in the Springfield Mobile Estates trailer park located atop the site. A number of these individuals are believed to have sold their trailers during the summer of 1985; however, a limited number of resident remain in the trailer park. A condominium complex (Bluegrass Hills) was constructed adjacent to the site to the north. The condominium complex has 44 single-family units in six buildings with approximately 100 residents.

Approximately 15 homes are located within a one-half mile of the site, along with a few other commercial establishments. Three homes are on the terrace adjacent to the mobile home park. Approximately 200 homes and condominiums are located within a one-

mile radius of the site, housing am estimated population of between 650 and 750 people.

The land use within a one-mile radius of the site is primarily low density residential housing, light agriculture, undeveloped forest land and commercial.

Natural resources in the vicinity of the site include groundwater, surface water, fish and game, arable land, forest, woodland, and minerals.

Users of the bedrock aquifer groundwater in the site vicinity are located primarily upgradient of the site. Two groundwater users have been identified downgradient of the site. Presently their water supply remains unaffected by the site. The remaining

residents receive Springfield municipal town water.

A more complete description of the site can be found in Section 1.1 of the Feasibility Study Report.

ROD DECISION SUMMARY paga 2 Old Springfield Landfill

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II. SITE HISTORY AND ENFORCEMENT ACTIVITIES

A. Response History

The Old Springfield Landfill, also referred to as the Will Dean Dump, was operated by the Town of Springfield between 1947 and 1968. Hazardous industrial waste from local industries was co-

disposed with municipal trash. Also, some of the industrial waste was disposed of in discrete trenches in addition to being mixed with municipal solid waste. Most hazardous material was disposed of in bulk liquid and semi-liquid form. Shortly after the site was closed in 1968 it was sold. The former landfill was developed for use as a mobile home park. At the time of the park's development, the Vermont Department of Health (DOH) recommended that drilled wells not be used to supply water to the park because the development was located over areas that had been used for chemical disposal. Municipal water lines were extended to serve the mobile homes. Springfield Mobile Home Estates trailer park currently

consists of 38 mobile homes. A six-building condominium complex and 13 single family residences are located near the site of the Old Springfield Landfill.

Shortly after the opening of the Springfield Mobile Estates trailer park, a nearby resident's complaint about foul-smelling water prompted an investigation of the site by the Vermont DOH and the Vermont Agency of Environmental Conservation (VTDEC). In response to finding volatile organic compound contamination in a spring and the in residential well near the mobile home park, the spring was abandoned and an affected home near the mobile homepark was connected to the public water supply.

EPA entered into the investigation of the Old Springfield Landfill site in 1976 to review VTDEC data on residential wells on the site. In late 1982, after the VTDEC requested that the site be reviewed for inclusion in the Superfund Program, the site was added to the National Priorities List of hazardous waste sites eligible to receive federal funding for study and cleanup. The results of EPA's initial Remedial Investigation (RI), released in September 1985, showed contamination in site soils, seeps, and ground-water. EPA determined that a supplemental RI was necessary to delineate the former waste disposal areas, and to better define the nature, extent, and potential adverse human health effects of site contamination.

Supplemental RI activities included taking samples from soil,

leachate seeps, residential wells, groundwater, and sediment at the site. These activities included a soil boring program in the trailer park area. Because of the potential for mobile home park residents to be exposed to contaminants during this soil boring


program, EPA temporarily relocated mobile home park residents between July 6 and July 18, 1987. EPA completed Phase I field investigations in October 1987, and Phase II in May 1988, and released the final RI report in June 1988. EPA has conducted the Phase II investigation simultaneously with the Feasibility Study, released in June 1988, to identify and evaluate cleanup alternatives for the site.

A more detailed description of the site history can be found in the Remedial Investigation, Supplemental Remedial Investigation

Report section 1.2, and the Feasibility Study report at section 1.1.

B. Enforcement History

On January 6, 1984, April 17, 1987, and May 14, 1987, EPA notified nine parties who either owned or operated the facility, generated wastes that were disposed of at the site, arranged for the disposal of wastes at the facility, or transported wastes to the facility, of their potential liability with respect to the site.

In January 1984, EPA had discussions with Emhart Corporation, Textron Incorporated, the Town of Springfield and other Potentially Responsible Parties (PRPs) about installing a water line to two private homes and conducting the Remedial Investigation and Feasibility Study. Emhart Corporation, Textron Corporation and the Town of Springfield came to an agreement on the installation of the water line only. EPA then used Trust Fund monies to conduct the Remedial Investigation and Feasibility Study.

EPA met with a committee of potentially responsible parties several times between June 26, 1987 and September 19, 1987 to keep them apprised of findings at the site. EPA also met with a committee of potentially responsible parties on June 29, 1988 to present the results of the Feasibility Study and the Proposed Plan and on a number of occasions in July and August of 1988. On August 24, 1988 the PRPs submitted written comments on EPA's proposed plan. The comments have been included in the administrative record.

C. Community Relations

Through the site's history, community concern and involvement has been high. EPA has kept the community and other interested parties apprised of the site activities through informational

meetings, fact sheets, press releases and public meetings.


In February 1985, EPA released a community relations plan which outlined a program to address community concerns and keep citizens informed about and involved in activities during remedial activities. In September 1985, EPA held an informational meeting in the town to describe the plans for Remedial Investigation and Feasibility Study.

On September 15, 1985 EPA held an informational meeting to describe the results of the Remedial Investigation.

On October 16, 1986, EPA held an informational meeting to discuss the Supplemental Remedial Investigation and Feasibility Study work plan.

Between July 6, and July 18, 1987, EPA held several meetings with residents of Springfield Mobile Estates to inform them of site conditions during the temporary relocation.

On March 29, 1988, EPA held a public meeting to discuss the results of the Supplemental Remedial Investigation and Endangerment Assessment.

On July 7, 1988, EPA held an informational public meeting to discuss the cleanup alternatives presented in the Feasibility Study and to present the Agency's Proposed Plan. The Agency also answered questions from the public during this meeting. From July 8 to August 24, the Agency held a seven week public comment period to accept comment on the alternatives presented in the Feasibility Study, the Proposed Plan, and all other documents previously released to the public. During that comment period, on July 21, 1988, the Agency held a public hearing to accept oral comments. A transcript of this meeting as well as written comments received, and the Agency's response to these comments are included in the attached responsiveness summary and are part of the Administrative Record. After the Record of Decision (ROD) is signed, EPA will publish notice of its decision in the local paper.

IV. SCOPE AND ROU2 OF RESPONSE ACTION

The selected remedy addresses management of migration (or groundwater) technologies to obtain an operable unit for remediation of water emanating from the seeps and present in known areas of groundwater contamination. The remedy provides for the following components: leachate collection and extraction of groundwater; treatment of leachate and extracted groundwater; institutional controls; long-term monitoring; and additional studies. This remedy does not address the source of groundwater or air contamination. After additional studies, remedial actions designed to control the contamination source will be evaluated.


V. SITE CHARACTERISTICS

A complete discussion of the site characteristics can be found in the Remedial Investigation and Supplemental Remedial Investigation Reports.

Chapter One of the Feasibility Study contains an overview of the Remedial Investigation. The significant findings of the Remedial Investigation are summarized below,

A. Hydrogeology/Groundwater

Hydrogeologic investigations were conducted at the site to characterize groundwater flow, contaminant transport and discharge to the seeps. A total of 36 monitoring wells (Figure 2) were installed in six geologic formations. Monitoring well water levels indicate that the hydrogeologic system is a sequence of unsaturated sands overlying low permeability, saturated glacial till which in turn is underlain by high permeability sands and gravel and fractured bedrock. The water-table surface is near the top of the glacial till over most of the site. Because of its low hydraulic conductivity, drainage from the till is slow, and the till is saturated over much of its thickness in most areas of the site. A localized, seasonally perched water table was observed in the western central part of the site. Beneath the till is the sand and gravel deposit which has a hydraulic conductivity nearly two orders of magnitude greater than the glacial till. The buried sand and gravel stream bed deposit acts as a drain, causing flow in the overlying glacial till to converge towards it.

Horizontal groundwater flow approaches the site from the south, but divergent flows to the east toward Black River and to the west toward Seavers Brook were observed in the immediate site vicinity. The most recent investigation determined that the site is a major recharge area and that there is a large downward component of groundwater flow.

The leachate seeps and springs on the outslopes of the site are major groundwater discharge zones. The major groundwater contamination at the site consists primarily of trichloroethene (TCE), tetrachloroethene (PCE), 1,1,1-trichloroethane (TCA), trans-l,2-dichloroethene, vinyl chloride, toluene, and total xylenes. The most concentrated of groundwater seep contamination was detected in two leachate seeps which flow from the face of the buried ravines_-*n the eastern portion of the site near Waste

ROD DECISION SUMMARY Old Springfield Landfill

paga 7

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Area 3. Groundvater contamination is found in greatest concentrations beneath the southeastern portion of the landfill in the southeast corner of the site. Attachment 1 shows the groundwater monitoring data.

B. Soil

The Remedial Investigation and Supplemental Remedial Investigation

Reports identify four major waste disposal areas. (See Figure 3) Waste Area One is the smallest and is located in northern portion of the site. Waste Areas 2 and 3 are on the eastern edge of the site. These two waste areas are former ravines that were filled during landfill operation. Waste area 4 is located at the southern end of the site and was the last active part of the landfill.

Soil samples in the Waste Areas show high levels of organic contaminants. Forty-five different contaminants were found in the site soils. They fall into four major groups of contaminant types. Polycyclic Aromatic Hydrocarbons (PAHs); Polychlorinated Biphenyls (PCBs); Chlorinated Aliphatic Hydrocarbons (CAHs) and Monocyclic Aromatic Hydrocarbons (MAH). Attachment 2 illustrates the contaminants, frequency of detection, and minimum and maximum values in soils.

A more complete discussion of the site characteristics can be found in the Supplemental Remedial Investigation Report.

VI. SUMMARY OF SITE RISKS

An Endangerment Assessment (EA) was performed to evaluate the potential adverse human health and environmental effects and estimate the probability and magnitude of potential adverse human health and environmental effects from exposure to contaminants associated with the site. Attachment 3 lists the.contaminants of concern that were selected for evaluation in the EA.

These contaminants constitute a representative subset of the more than seventy-five -contaminants identified *t the site during the Remedial Investigation. The contaminants were selected to represent potential onsite and offsite hazards based on toxicity, level of contamination, mobility, and persistence in the environment.

Potential human health effects associated with the contaminants of concern in subsurface soils groundwater, sediments and air were estimated quantitatively through the development of several hypothetical exposure scenarios. Incremental lifetime cancer risks and a measure of the potential for non-carcinogenic adverse

ROD DECISION 6UKKXRY page 9 Old Springfield Landfill

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health effects were estimated for the various exposure scenarios. Exposure scenarios were developed to reflect the potential for exposure to hazardous substances based on the characteristic uses and location of the site.

a. Direct Contact with Soils

Human health risks were calculated for an adult, assuming contact with surface soils once or twice per week via gardening or other activities. The excess lifetime cancer risks range from 3 x 10"7 under site-wide average contaminant concentrations and 2 x 10"5 in the site-wide maximum concentrations. Host of the risk is attributable to PCBs and PAHs. Hazard indices are less than one under both cases.

For children (one to six years old) assuming play in the soil for six months of the year two time per week under the average case and 4 times per week under the maximum case, the excess lifetime on-site incremental cancer risk ranged from 1 x 10~7 under site-

wide average contaminant concentrations and 2 x 10~5 under site-

wide maximum concentrations. These estimates include both direct contact and soil ingestion and the risks are mainly attributable to PCBs and PAHs. Hazard indices are less than one under both cases.

b. Groundwater

Groundwater on site is not currently used for drinking water; however, according to the EPA Groundwater Protection Strategy the aquifer underlying the site is classified as a Class IIB aquifer (i.e. having a potential for future use). Therefore the lifetime cancer risk and the non-carcinogenic health risks associated with the ingestion of on-site groundwater were assessed. The excess lifetime cancer risks range from 1 x 10*~3 under site-wide average contaminant concentrations and 7 x 10"2 under site-wide maximum concentrations. The chemicals contributing most to the risk are vinyl chloride, 1,1-dichloroethene and PCBs.

The future lifetime excess cancer risks for groundwater in the western area of the site were calculated to be 6 x 10~4 under average contaminant concentrations and 7 x 10~* under maximum contaminant concentrations found on the western slope. Vinyl chloride and 1,1-dichloroethene contribute most to the risk.

c. Air

Risks due to inhalation exposure to landfill gas contamination and the volatilization of contaminants from leachate seeps were modeled. The landfill gas exposure route indicates an excess lifetime cancer risk of 9 x 10"5 under site-wide average


contaminant concentrations and 5 x 10~3 under site-wide maximum contaminant concentrations. Chemicals contributing most to the risk are benzene, chloroform and trichloroethene. Using the assumption that the concentrations of contaminants in the air at the nearest off-site residence are the same as on-site, the average and maximum excess lifetime cancer risks are the same off-

site as on-site.

Exposure risks from volatilized contaminants from leachate seeps indicate a lifetime excess cancer risk of l x 10~* under site-

wide average contaminant concentrations and 1 x 10~3 under maximum contaminant concentrations. Chemicals contributing most to the risk are vinyl chloride, 1,1-dichloroethene and 1,1-dichloroethane.

d. Surface Water

Excess lifetime cancer risks associated with current consumption of fish from the Black River based on concentrations estimated from the mass balance model are 3 x 10-8 and 2 x 10-6 for the average and plausible maximum cases, respectively, with nearly all of the risk attributable to PCBs.

A complete discussion of risks can be found in Section 1.4 of the Feasibility Study and the Endangerment Assessment.

VTI. DOCUMENTATION OF SIGNIFICANT CHANGES

EPA published a proposed plan (preferred alternative) for remediation of the site on July 7, 1988. The remedy published in the proposed plan provides for source control by combining the following components: capping according to RCRA regulations and performance standards set for in RCRA guidance; leachate collection and extraction of groundwater; treatment of leachate and extracted groundwater at a treatment facility; institutional controls; long-term monitoring; arid relocation of residents.

During the public comment period several commenters, including the State of Vermont, indicated that EPA's proposed plan for source control did not adequately address lateral groundwater flow through buried waste, or the potential for bedrock groundwater contamination. On August 26, 1988 EPA received a letter from the State of Vermont conveying its concern with the adequacy of the proposed cap to protect groundwater. In subsequent discussions between EPA and the State, the governments agreed that further studies would be appropriate before selecting a final remedial action; however they also agreed that the seep collection and groundwater extraction and treatment portion of the remedy was adequate for the specific limited exposure routes concerned and


should be selected as an operable unit. As the relocation was based on the need to move residents while constructing the cap, no decision is being made with respect to relocation options in this Record of Decision.

In the management of migration portion of the proposed plan, EPA stated that the extracted groundwater and leachate would be treated at a facility to be constructed onsite. During the public comment period, EPA received information that the Town of Springfield has the willingness and capacity to treat the extracted groundwater and leachate at their Publicly Owned Treatment Works (POTW) located about one-half mile from the site. It has not been determined however, whether the POTW has the ability, either with or without pretreatment, to treat the wastes. This determination will be made during the remedial design. Since it may be more easily implementable, cost-effective, and have greater community acceptance, use of the POTW is included in the remedy vith a provision for on-site treatment if acceptable treatment at the POTW cannot be demonstrated and ensured.

In the proposed plan, EPA specified leachate collection designs. With respect to the leachate collection portion of this remedy, EPA has modified the remedy to allow for alternate designs as long as the alternate design meet the objectives and performance standards outlined. This modification was made to accommodate the potential constructability difficulties that may be encountered due to the steep slopes surrounding the landfill.

VTII. DEVELOPMENT AND SCREENING OF ALTERNATIVES

A. Statutory Requirements/Response Objectives

Prior to the passage of the Superfund Amendments and Reauthorization Act of 1986 (SARA), actions taken in response to releases of hazardous substances were conducted in accordance with CERCLA as enacted in 1980, and the revised National Oil and Hazardous Substance Pollution Contingency Plan (NCP), 40 CFR Part 300, dated November 20, 1985. Until the NCP is revised to reflect SARA, the procedures and standards for responding to releases of hazardous substances, pollutants and contaminants shall be in accordance with Section 121 of CERCLA and to the maximum extent practicable, the current NCP.

Under its legal authorities, EPA's primary responsibility at Superfund sites—is to undertake remedial actions that"are protective of human health and the environment. In addition, Section 121 of^CERCLA establishes several other statutory requirements and preferences, including: a requirement that EPA's


remedial action, when complete, comply with applicable or relevant and appropriate environmental standards established under federal and state environmental lavs unless a statutory waiver is granted; a requirement that EPA select a remedial action that is cost-

effective and that utilizes permanent solutions and alternative treatment technologies or resource recovery technologies to the maximum extent practicable; and a statutory preference for remedies that permanently and significantly reduce the volume, toxicity or mobility of hazardous wastes over remedies that do not achieve such results through treatment. Response alternatives were developed to be consistent with these Congressional mandates.

A number of potential exposure pathways were analyzed for risk and threats to public health and the environment in the Endangerment Assessment. Guidelines in the Superfund Public Health Evaluation Manual (EPA,1986) regarding development of design goals and risk analyses for remedial alternatives; were used to assist EPA in the development of response actions. As a result of these assessments, remedial response objectives were developed to mitigate existing and future threats to public health and the environment. These response objectives are to:

1. Prevent direct contact (incidental ingestion and dermal absorption) with contaminated surface soils throughout the site by residents and by construction workers;

2. Prevent the volatilization of contaminants from contaminated soils, wastes, and leachate seeps;

3. Prevent the contamination of fish in the Black River by preventing leaching of contaminants from site soils to shallow groundwater to the bedrock aquifer with subsequent discharge to Seavers Brook and into the Black River; and

4. Prevent the leaching of contaminants from site soils to shallow groundwater with subsequent transportation from the shallow groundwater to the potable bedrock aquifer.

As discussed above, subsequent to the publication of the proposed plan, the scope to this Record of Decision was limited to an operable unit for seep collection and treatment and limited groundwater extraction and treatment. Therefore, the remedial objectives addressed by this ROD include only the those associated with the groundwater emanating from leachate seeps; these include objectives 1, and to a limited extent 2, 3, and 4.

B. Technology and Alternative Development and Screening


CERCLA, the NCP, and EPA guidance documents, including "Guidance on Feasibility Studies Under CERCLA" dated June 1985, and the "Interim Guidance on Superfund Selection of Remedy'[EPA Office of Solid Waste and Emergency Response (OSWER), Directive No. 9355.019 (December 24, 1986) set forth the process by which remedial actions are evaluated and selected. In accordance with these requirements and guidance documents, treatment alternatives were developed for the site ranging from an alternative that, to the degree possible, would eliminate the need for long-term management (including monitoring) at the site, to alternatives involving treatment that would reduce the mobility, toxicity, or volume of hazardous substance as their principal element. In addition to the range of treatment alternatives, a containment option involving little or no treatment and a no-action alternative were developed in accordance with Section 121 of CERCLA.

Section 121(b)(l) of CERCLA presents several factors that at a minimum EPA is required to consider in its assessment of alternatives. In addition to these factors and the other statutory directives of Section 121, the evaluation and selection process was guided by EPA document "Additional Interim Guidance for PY'87 Records of Decision " dated July 24, 1987. This document provides direction for consideration of SARA cleanup standards and sets forth nine criteria that EPA should consider in its evaluation and selection of remedial actions. The nine criteria are:

1. Compliance with Applicable or Relevant and Appropriate Requirements (ARARs).

2. Long-term Effectiveness and Permanence.

3. Reduction of Toxicity, Mobility or Volume.

4. Short-term Effectiveness.

5. Implementability.

6. Community Acceptance.

7. State Acceptance.

8. Cost.

9. Overall Protection of Human Health and the Environment.

Chapter 4 of the Feasibility Study identified, assessed and screened technologies based on implementability and effectiveness. These technologies were combined into source control (SC),


management of migration (MM) and Resident Relocation (RR) alternatives. Chapter Five in the Feasibility Study presented the remedial alternatives developed by combining the technologies identified in the previous screening process in the categories required by OSWER Directive No. 9355.0-19. The purpose of the initial screening was to narrow the number of potential remedial actions for further detailed analysis while preserving a range of options. Each alternative was then evaluated and screened in Chapter 6 of the Feasibility Study on the basis of effectiveness, implementability and cost. In summary, of the seven source control, six management of migration, and three resident relocation remedial alternatives screened in Chapter 6, five source control, two management of migration and three resident relocation options were retained. As noted above, this ROD addresses only the leachate seeps and to a limited extent, groundwater contamination; source control and resident relocation alternatives will be addressed in a subsequent ROD or RODs; therefore, Attachment 4 identifies only the management of migration alternatives that were retained through the screening process as well as those that were eliminated from further consideration.

IX. DESCRIPTION /SUMMARY OF THE DETAILED AND COMPARATIVE ANALYSIS OF ALTERNATIVES

This section presents a narrative summary and brief evaluation of each alternative according to the evaluation criteria described above. A detailed tabular assessment of each alternative can be found in Chapter 7 of the Feasibility Study at Tables 7-28 and 7-34.

Management of Migration (MM) Alternatives Analyzed

Management of Migration alternatives address, in part, contaminants that have migrated from the original source of contamination. At the Old Springfield Landfill site, some

contaminants have migrated from the source area into groundwater and emanated as leachate seeps on the east and west side of the landfill. The management of migration alternatives evaluated for the site include a minimal no action with monitoring alternative and a continuous leachate and groundwater extraction followed by treatment alternative.

MM-1 Management of Migration Alternative 1 No Action with Monitoring Alternative

ROD DECISION SUMMARY Old Springfield Landfill

Estimated Present Worth Cost: $1,628,000. Annual Operation and Maintenance Cost: $86,000.

The law requires consideration of this alternative as a baseline comparison to other management of migration alternatives considered. No action for groundwater would consist of installing fences around leachate seeps, eliminating the use of septic systems for on-site residents and instituting a long-term sampling program to assess the movement of contamination from the landfill.

This alternative does not provide adequate protection of human health and the environment in either the long or short-term, because contaminated leachate would continue to seep from the eastern and western slope, volatilize and flow to surface water in an uncontrolled manner. It does not reduce the toxicity, mobility or volume of contaminants. This alternative does not meet any of the remedial objectives relating to migration of contaminants such as reducing direct contact with leachate, eliminating

volatilization of contaminants to the air from seeps, or eliminating the migration of contaminants to the Black River and bedrock aquifer. Also, this alternative does not meet ARARS.

MM-5 Management of Migration Alternative 5 Continuous Collection of Leachate Seeps with Groundwater Extraction and On-site Treatment

Estimated Present Worth Cost: $5,374,000 Annual Operation and Maintenance Cost: $173,000.

This alternative would involve construction of an underground collection system to collect all contaminated seeps from the eastern and western slopes descending from the site; the installation of wells on the western side of the site near Will Dean Road to extract contaminated groundwater for treatment; and the treatment of the collected leachate and extracted groundwater onsite.

This alternative will be protective of human health and the environment by eliminating the pathway for contaminants to volatilize at the seeps by collecting the seeps underground before contact with the air. It will also reduce the potential for contaminants to travel into the Black River and Seavers Brook via surface drainage, thus reducing the possible contamination of fish in those rivers. It will reduce the mobility of contaminants by collecting the seeps and treating them before they can discharge to surface water or leach further into the groundwater. This alternative will attain ARARs.

O

COST SUMMARY ftS OF O4/25/89 Pace i OLD SPRINGFIELD LANDFILL, VT (SSIQ = i 39) Prepared: O5/11/88 Revised: O3/21/89

EPA EXPENDITURES

REGIONAL ^AYROLL EXPENSES

REGIONAL TRftVEL EXPENSES

REGIONAL INDIRECT COST

OTHER REGIONAL COST

HEADQUARTERS PftYROLL EXPENSES

HEfiDQUARTERS TRflVEL EXPENSES

folO.

$ 62725. 97

2274.IS

£31749. OO

1O5. OO

63

24O.76

CONTRfiCT LrtB PROGRAMS (CLP)

- V I R R 331142. fc>

EMERGENCY REMOVfiL CLEfiNLiP (ERC) SERVICES CONFRftCf

- G. H. MATERIALS (68-01-8893)

FIELD i\VESTIGRTION TEHI^ IF:T> CDNTHPCT

21O56. 14

- I'JJS 168-O1-7346) i95. 17

IKTERAGENCV fiGREEMENTS

- DEPfiRTMENT OF THE INTERIOR (LWi4156601) 3O64.5O

NfiTIONfiL ENFORCEMENT INVESTIGATION (NEI> CENTER EXPENSES

- TECHLftW-CGNTRfiC f EVIDENCE filJDI r TEAM (Sd-Ol-7363) 1568. 9O

OVERFLIGHT vOVR) CONTRACT

- EPIC 3IOTMET1CS 2779.17

-'"'- Pending review of update package **

COST SUMMARY OS OF OLD SPRINGFIELD LANDFILL, VT (SSID = 1 3'3)

Page

Prepared: O5/11/88 Revised: O3/21/89

REMEDIAL (REM) CONTRACT

- MLJS (68-O1-6699) 107bb38. O7

- EBASCQ (6a-Ol-7£5O> 1OO4&5O. 19

STftTE COOPERATIVE AGREEMENTS :bS-Ol-73t,7> 7168. 3£

TECHMCOL ENFORCEMENT SUPPORT (TES) CONTRACT

- PLLI ANCE/GCft

ATTACHMENT 2 'A. •• .L-̂ 1 t . j. ' • - •

OLD SPRINGFIELD LANDFILL DRAFT SCOPE OF WORK

Table of Contents

I. INTRODUCTION AND PURPOSE 1

II. DEFINITIONS 1

III. REMEDIAL ACTION OVERVIEW 4

IV. REMEDIAL ACTION 5 A. Design of the Leachate Collection System and

Groundwater Extraction System. 5 B. Evaluation and Design of the Groundwater

Extraction and Leachate Collection Treatment System. 7

C. Construction, Operation and Maintenance 7 D. Monitoring 7 E. Demonstration of Compliance 10 F. Compliance with Other Laws 10

V. SITE ACCESS. INSTITUTIONAL CONTROLS, SECURITY, AND SITE CLOSURE 11 A. Property Access 11 B. Institutional Controls 11 C. Site Security 11 D. Closure 12

VI. SUBMITTALS 12 A. POTW Determination Activities 12

1. Schedule 12 B. Treatment System Activities. 12

1. Schedule. 12 2. Contents of the Treatment System Design

Workplan. 12 C. Monitoring Plan. 13

1. Schedule. 13 D. Remedial Design Activities 14

1. Schedule 14 2. Contents of the Remedial Design Workplan ... 14 3. Contents of the Remedial Design. 17

E. Remedial Action 18 1. Schedule. 18 2. Closure. 19 3. Design Modifications. 19 4. Completion of Construction Determination. . . 19 5. Operation Modifications. 20

VII. EPA REVIEW OF PLANS. WORKPLANS,, REPORTS, AND OTHER ITEMS 20

APPENDIX 1

OLD SPRINGFIELD LANDFILL Remedial Action Scope of Work

I. INTRODUCTION AND PURPOSE

The purpose of this Remedial Action Scope of Work (SOW) is to define the remedial action to be undertaken and funded by the Settling Defendants under this Partial Consent Decree at the Old Springfield Landfill Superfund Site Study Area in Springfield, Vermont. The SOW describes the remedial activities based on the first operable unit Record of Decision (ROD) and sampling results available to EPA as of September 22, 1988. The SOW defines the Settling Defendants' activities and deliverable obligations, and it establishes a schedule for these activities and deliverables.

II. DEFINITIONS

The following definitions shall apply to this Remedial Action Scope of Work:

A. "Site" or "Old Springfield Landfill Superfund Site" shall mean the "facility," as the term is defined in Section 101(9) of CERCLA, 42 U.S.C. Section 9601(9), where disposal of hazardous substances was conducted, and where hazardous substances have come to be located. The facility is located within the city limits of Springfield, Windsor County, Vermont, as shown on the map attached as Appendix 2. The site includes, but is not limited to, a landfill area, disposal pit and leachate seeps.

B. "Site Area" shall mean the Site and the surrounding area which is actually or potentially affected by air, groundwater, or surface water releases originating at the Site.

C. "Record of Decision" or "ROD" shall mean the EPA Record of Decision relating to the Site, signed September 22, 1988, by the Regional Administrator EPA Region I and all attachments thereto.

D. "Administrative Order" or "AO" shall refer to the Administrative Order, Docket Number 1-89-1019 signed by the Regional Administrator March 10, 1989.

E. "Remedial Investigation/Feasibility Study" or "RI/FS" shall refer to the Remedial Investigation for the Site prepared by NUS, dated September 1985, the Supplemental Remedial Investigation for the Site, dated June 1988, the Endangerment Assessment for the Site, dated June 1988, and the Feasibility Study for the Site, dated

June 1988, prepared by Ebasco Services for the Environmental Protection Agency (EPA).

F. NCP shall mean the National Contingency Plan promulgated pursuant to CERCLA Section 105, 42 U.S.C. Section 9605, codified 40 CFR Part 300, including any amendments thereto.

G. "CERCLA" shall mean the Comprehensive Environmental Response, Compensation, and Liability Act of 1980, as amended 42 U.S.C Section 9601 et seq.

H. "Hazardous substances" shall mean both those substances defined as hazardous substances under CERCLA Section 101(14), 42 U.S.C. Section 9601(14), and those substances defined as a hazardous waste under RCRA Section 1004(5), 42 U.S.C. Section 6903(5) and under the Vermont .

I. "Performance Standards" shall mean the cleanup standards for groundwater and leachate, which, at a minimum, include Maximum Contaminant Levels (MCLs) established under the Safe Drinking Water Act, including but not limited to the following MCLs established at 40 CFR Part 141, Subpart B:

Benzene 5 ppb 1,1-dichloroethene 7 ppb Trichloroethene (TCE) 5 ppb Vinyl Chloride 2 ppb

The groundwater and leachate shall also be assessed for the presence of chemical mixtures, should more than one chemical be detected. Assessment of the risk associated with the mixture will be performed to assure that Performance Standards are protective of human health and the environment.

Groundwater shall be treated until such time that Performance Standards are attained above bedrock and at and beyond the northern boundary of Waste Area 1 to the north, the eastern leachate seeps to the east, the southern boundary of Waste Area 4 to the south, and Will Dean Road to the east.

Leachate shall be treated until such time that Performance Standards are attained at and beyond Route 11 to the east and Seavers Brook Road to the west.

J. "Design" shall mean an identification of the technology and its performance and operational specifications, in accordance with all applicable federal, state, and

local laws, including, but not limited to the following:

1. all computations used to size units, determine the appropriateness of technologies, and the projected effectiveness of the system;

2. layout of leachate collection and groundwater extraction systems and treatment facilities including size and placement of leachate collection structures, well placement, pump placement, pump rates, treatment facility placement, effluent discharge area, and the location of pipelines between the leachate collection, extraction wells and treatment system;

3. scale drawings of the leachate collection structures and groundwater extraction systems including, but not limited to, trench excavation, leachate collection, and well cross sections;

4. quantitative analysis demonstrating the anticipated effectiveness of the remedial design to achieve Performance Standards and remedial action objectives;

5. technical specifications which detail the following:

a. size and type of each major component;

b. required performance criteria of each major component;

c. type of pipes and joints to be used;

d. pipe installation including excavation, backfilling, grading and seeding, as necessary; and

e. components of effluent quality discharge.

6. description of extent of ambient air monitoring including equipment, monitor location, and data handling procedures; and

7. description of the land easements required, to be supplied with the construction plans and specifications.

III. REMEDIAL ACTION OVERVIEW

The ROD describes the following remedial response objectives of remedial action for the Site:

1. Prevent direct contact (incidental ingestion and dermal absorption) with contaminated surface soils throughout the Site by residents and construction workers;

2. Prevent the volatilization of contaminants from contaminated soils, wastes, and leachate seeps;

3. Prevent the contamination of fish in the Black River by preventing leaching of contaminants from Site soils to shallow groundwater to the bedrock aquifer with subsequent discharge to Seavers Brook and into the Black River; and

4. Prevent the leaching of contaminants from Site soils to shallow groundwater with subsequent transportation from the shallow groundwater to the potable bedrock aquifer.

The September 22, 1988 first operable unit ROD partially addresses objectives 2, 3, and 4.

The Partial Consent Decree and this SOW provide for the implementation of the remedial action that was selected in the ROD. Components of this operable unit remedial action, include the following: leachate collection and extraction of groundwater; treatment of leachate and extracted groundwater; institutional controls; and long-term monitoring. Measures for implementing this remedial action outlined below include:

A. Design of the Leachate Collection and Groundwater Extraction Systems;

B. Evaluation and Design of the Groundwater and Leachate Treatment System;

C. Construction, Operation, and Maintenance of the Leachate Collection, Groundwater Extraction, and Treatment Systems;

D. Institutional Controls; and

E. Long-Term Monitoring.

IV. REMEDIAL ACTION

The Settling Defendants shall remediate the sand and gravel aquifer above bedrock and the leachate seeps by collecting and treating, to the maximum extent practicable, all leachate and

groundwater until such a time that leachate and groundwater contaminant levels are reduced to Performance Standards at the locations specified in Section II.I of this SOW. Implementation shall involve the design, construction and operation of leachate collection, groundwater extraction and treatment systems. It shall be determined by EPA and the Vermont Department of Environmental Conservation (VT DEC), whether treatment will be at the Town of Springfield Publicly Owned Treatment Works (POTW) or at an on-Site facility to be constructed as part of this Remedial Action. In accordance with the ROD and Partial Consent Decree, the Settling Defendants shall conduct the following remedial actions in a manner that meets the objectives of the first operable unit ROD.

A. Design of the Leachate Collection System and Groundwater Extraction System. The Settling Defendants shall design and construct a leachate collection system and groundwater extraction system. The leachate collection system and groundwater extraction system shall:

1. Collect all leachate in a collection system at or upgradient of the point of any seep emanation in a manner which prevents releases at the ground surface and to the air.

2. Collect all ten of the seeps on the eastern slope identified in the RI/FS, all four of the seeps on the western slope identified in the RI/FS, and any other leachate seep between Route 11 to the east and Seavers Brook Road to the west which contains detectable levels of organic contaminants.

3. Minimize the potential for the development of other contaminated leachate seeps outside the collection system.

4. Provide for simple extension of the leachate collection system to collect additional contaminated leachate seeps, if they should develop.

5. Extract contaminated groundwater, to the maximum extent practicable, from the sand and gravel zone above bedrock on the western portion of the Site as close to the Waste Areas as defined in the Supplemental Remedial Investigation Report as practicable.

6. Be supported by quantitative analysis that demonstrates the system's ability to collect contaminated leachate to the extent of technical practicability at the maximum flow rates that can

reasonably be expected to occur at some time in the future. The design activities for the leachate collection and groundwater extraction system shall, at a minimum, include:

a. Conducting flow estimating activities at all eastern and western leachate seeps for the purpose of measuring seasonal fluctuations in seep discharge, and sampling all seeps to define the horizontal extent of groundwater contamination.

b. Performing soil exploration and sampling activities to define the lithology, thickness, stratigraphy, and physical characteristics of the soils.

c. Preparing a design for a system to collect leachate to the extent of technical practicability in order to prevent the discharge of leachate into surface drainage courses and the volatilization of organic compounds into the atmosphere at leachate seeps.

d. Conducting tests of the sand and gravel formation aquifer to determine aquifer hydraulic properties including aquifer yield and the area of contribution to the extraction wells under variable pumping conditions.

e. Preparing a design for a system to extract contaminated groundwater to the extent of technical practicability. The design is to ensure that this extraction system shall achieve the Performance Standards outlined in the ROD and Section II.I of this SOW in the shortest practicable timeframe.

f. A plan for handling any excavated, contaminated soil in a manner consistent with CERCLA and the NCP, including, if necessary, onsite treatment or off-site disposal.

B. Evaluation and Design of the Groundwater Extraction and Leachate Collection Treatment System. The collected leachate and extracted groundwater shall be conveyed to a

treatment system which shall meet all federal and state requirements for treatment, discharges to surface water, handling of treatment residuals, and maintaining acceptable air emission levels. A demonstration of the POTW's ability, capacity and willingness to treat the leachate and groundwater had not been made. Therefore the Settling Defendants shall submit a permit application(s) to treat the extracted groundwater and leachate at the POTW while meeting all applicable federal and state requirements. This evaluation shall include the assessment of pretreatment requirements.

If it is determined by EPA and VT DEC that the POTW cannot treat the collected leachate and extracted groundwater, then the Settling Defendants shall design and construct a treatment system that ensures treatment of leachate and extracted groundwater to water quality levels acceptable for discharge as determined by VT DEC and the EPA and that controls potentially hazardous air emission in a manner acceptable to the EPA and VT DEC, and which does so in a manner which is protective of public health and the environment.

C. Construction, Operation and Maintenance. Upon receipt of the approval of the Remedial Design for the leachate collection system, groundwater extraction system and treatment systems, the Settling Defendants shall construct the leachate collection, groundwater extraction and treatment systems. The Settling Defendants shall operate and maintain the leachate collection, groundwater extraction and treatment systems until all Performance Standards are achieved and maintained.

D. Monitoring. A monitoring plan shall be implemented to assess the effectiveness of the remedial action. As outlined in the ROD, the monitoring program will address groundwater, surface water, sediment, soil/debris, leachate and air.

1. The objectives of the monitoring plan are:

a. to monitor the effectiveness of this and subsequent remedies;

b. to continue to monitor the bedrock aquifer to evaluate the possibility that there are new or existing contaminated bedrock flows, discharge points, or residential wells which have not been detected with the current monitoring data;

c. to identify further impacts to public health and the environment; and

d. to monitor groundwater changes due to the implementation of this and subsequent remedial actions.

2. Specifically, the monitoring plan will include, but not be limited to:

a. installing and monitoring of current and new bedrock wells, including locations east of the Black River, to be determined by fracture trace analysis, remote geophysical methods, or other techniques;

b. monitoring of residential wells;

c. inspecting for and monitoring of any new seeps;

d. monitoring of the collected untreated and treated leachate and groundwater;

e. monitoring of surface water;

f. if more than one chemical is detected, analyzing and assessing groundwater for the presence of chemical mixtures and any potential cumulative risk;

g. developing of a statistical test to determine when groundwater and leachate attains the Performance Standards described above; and

h. monitoring the effectiveness of the leachate collection, groundwater extraction and treatment system.

3. The condition and usefulness of existing wells shall be assessed and compared with future data needs using visual, down-hole camera emd pump test techniques during initial field activities.

4. A comprehensive monitoring well network shall be developed to provide sufficient information to evaluate dispersion of the* contaminant plume, and the distribution of contaminant migration off-Site.

5. Monitoring wells shall be sampled and analyzed on a quarterly basis until completion of the source control remedial action. After completion of the source control remedial action, monitoring wells

8

shall be sampled and analyzed on a quarterly basis for the first three years. Samples in years 4 and 5 after completion of the final remedial action shall be done semi-annually. Samples in years 6 through 10 shall be collected once per year. After year 10 well sampling shall be conducted every other year.

6. Initially, all samples shall be analyzed for Hazardous Substance List (HSL), Volatile Organic Compounds (VOCs), Semi-Volatile Organic Compounds (SVOCs), Polychlorinated biphenyls (PCBs), and metals. Changes in the specific parameters, duration, and frequency may be proposed by EPA or the Settling Defendants and approved by EPA as outlined in Section XXX of the Partial Consent Decree depending on sampling results and observed trends.

7. Monitoring Plan Reports. Monitoring Plan Reports shall be submitted and shall contain but not be limited to:

a. a map of the Site showing sample locations;

b. tabular representation of laboratory results by each media including comparison with any standard levels;

d. laboratory results on a computer disk in a spreadsheet file that is similar in form to Lotus 1-2-3 and compatible with EPA Region I software;

e. data validation packages;

f. interpretation of any trends in data;

g. reporting of any unusual conditions observed at the Site, or observed during sampling events; and

h. recommendations.

E. Demonstration of Compliance. The Settling Defendants shall prepare a plan for demonstrating to EPA that the groundwater and leachate treatment has attained all Performance Standards at all points of compliance pursuant to Section II.I above. This plan for demonstrating compliance will include, but not be limited to, a statistical analysis demonstrating attainment of Performance Standards. As part of the demonstration of effectiveness, fate and transport modeling and model

verification will be used. To determine whether the Performance Standards have been met, the Settling Defendants shall compare the groundwater quality at each point of compliance according to statistical procedures of 40 CFR Section 264.97(h).

Treatment to 5 ppb for TCE and 2 ppb for vinyl chloride is expected to reduce other compounds identified in groundwater to non-detectable levels. However, in the event that any other compounds are at detectable levels upon meeting the TCE and vinyl chloride performance standard for groundwater, it will be necessary to determine the overall risk associated with all compounds detected. A determination will be made by EPA upon achieving 5 ppb for TCE and 2 ppb of vinyl chloride in groundwater as to whether the aquifer cleanup has satisfied the performance standard.

Compliance with Other Laws. In accordance with Section 121(e)(1) of CERCLA, no Federal, State, or local permit shall be required for the portion of the remedial action conducted entirely on-Site. The Settling Defendants shall, however, meet the substantive technical requirements and standards necessary to obtain Federal and State permits for all aspects of the remedial action.

Remedial action shall be conducted in accordance with the applicable or relevant portion of the following standards:

1. The Solid Waste Disposal Act, as amended, 42 U.S.C. Sections 6901 et seq.. and regulations promulgated thereunder;

2. The federal Clean Water Act (CWA), 33 U.S.C. 1251 et seq.. and regulations promulgated thereunder;

3. The federal Clean Air Act (CAA), 42 U.S.C. Sections 7401 et seq., and regulations promulgated thereunder;

4. The Safe Drinking Water Act (SDWA), 42 U.S.C. Section 300(f) et seq., and regulations promulgated thereunder;

5. The Resource Conservation and Recovery Act (RCRA), 42 U.S.C. Section 9601 et seg., and regulations promulgated thereunder; arid

6. All statutes and regulations identified in the ROD.

10

V. SITE ACCESS. INSTITUTIONAL CONTROLS, SECURITY. AND SITE CLOSURE

A. Property Access. In order to implement the remedial action provided by the Partial Consent Decree and this SOW, the Settling Defendants shall comply with the requirements of Section X of the Partial Consent Decree regarding Site access.

B. Institutional Controls. The Settling Defendants shall obtain deed restrictions and other institutional controls which ensure non-interference with the performance of the remedial action and which will prohibit the use of the disposal area, including groundwater thereunder, after completion of the remedial action.

As outlined in the ROD, Town of Springfield Ordinance 88-2 shall be enforced in the area between bounded by Route 11 on the east, Mr. Curtin's present property boundary to south, Seavers Brook Road on the west and Mr. Curtin's present property boundary on the north, until such time that a demonstration of compliance is made in accordance with Section IV.E above. After such demonstration is made the ordinance will be enforced as defined in Section II.I above.

C. Site Security. The Settling Defendants shall prepare a Site Security Plan which provides for Site security in accordance with 40 CFR Section 264.117(b) and 40 CFR Section 264.14. The Site Security Plan shall include, but not be limited to, a description of the measures to be taken to assure the safety of the personnel and equipment on-Site, safety of residents on and off-Site, and to provide an effective barrier against unauthorized public access. The security plan will be designed to reflect and complement the level of work activity on-Site, and shall incorporate 24-hour security, if found to be necessary by EPA.

D. Closure. After EPA certifies that the Settling Defendants have made the demonstration of compliance in Section IV.E above with the Performance Standards in Section II.I above, the operation of the leachate collection, groundwater extraction and treatment systems shall be terminated. Following the demonstration of compliance under Section IV.E above, the Settling Defendants shall monitor the groundwater and leachate for at least three years to demonstrate the maintenance of the Performance Standards in accordance with procedures of 40 CFR Sections 2.100(d) and (f). If at any time during the Settling Defendants' obligations under the Partial Consent Decree and this SOW, the Performance Standards are exceeded, the Settling Defendants shall restart the leachate collection

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and groundwater extraction system and treatment system. The Settling Defendants' obligation to monitor groundwater shall terminate upon issuance of a certificate of completion pursuant to Section 'XVI of the Partial Consent Decree.

VI. SUBMITTALS

A. POTW Determination Activities

1. Schedule. Within thirty (30) days of the effective date of this Partial Consent Decree, the Settling Defendants shall submit to EPA and the State complete permit application(s) for use of the POTW and any associated actions necessitated by the use of the POTW, for review and approval pursuant to Section VII of this SOW.

B. Treatment System Activities.

1. Schedule. Within thirty (30) days of notification by EPA and VT DEC that the permit for use of the POTW for treatment of collected leachate and extracted groundwater has been denied, the Settling Defendants shall submit to a Treatment System Workplan for review and approval pursuant to Section VII of this SOW.

2. Contents of the Treatment System Design Workplan. The Settling Defendants shall prepare the Treatment System Design Workplan that specifies and describes all tasks to be accomplished to support development and design of the on-Site treatment system, to be undertaken to facilitate the design and to ensure the effectiveness of the Treatment System reguired by the ROD. This shall include any modifications to the leachate collection and groundwater extraction systems necessary to accommodate the use of on-Site treatment, The Settling Defendants shall prepare plans for pilot tests and field studies necessary to design and implement the Treatment System. The study shall contain a detailed description, a statement of purposes and objectives, a description of the specific activities necessary to conduct the study, and a schedule for implementation of the activities. The Treatment System Design Workplan shall contain a schedule for accomplishing each of the tasks necessary for the development of the Treatment System portion of the Remedial Design.

The Treatment System Design Workplan shall include,

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at a minimum, the components as in Section VI.D.2.a.i-v, and the schedules outlined in Section VI.D.2.b.i-ii.

In the event of approval or modification of the Treatment System Design Workplan, the Settling Defendants shall, within seven (7) days of receipt of such approval or modification, commence implementation of the activities set forth in the approved Treatment System Design Workplan.

C. Monitoring Plan.

Schedule. Within thirty (30) days of the effective date of this Partial Consent Decree, the Settling Defendants shall submit a Monitoring Plan as described in Section IV.D of this SOW for review and approval pursuant to Section VII of this SOW.

In the event of approval or modification of the Monitoring Plan, the Settling Defendants shall, within seven (7) days of receipt of such approval or modification, commence implementation of the activities set forth in the approved Monitoring Plan

Within forty-five (45) days of the last day in the field from each sampling event, the Settling Defendants shall submit to EPA and VT DEC a Monitoring Plan Report as described in Section IV.D.6 above. This Monitoring Plan Report shall contain the results of sampling effort conducted to fulfill the requirements of Section IV.D. above.

D. Remedial Design Activities

1. Schedule. Within sixty (60) days of the effective date of this Partial Consent Decree, the Settling Defendants shall submit the Remedial Design Workplan for review and approval pursuant to Section VII of this SOW.

In the event of approval or modification of the Remedial Design Workplan, the Settling Defendants shall, within seven (7) days of receipt of such approval or modification, commence implementation of the activities set forth in the approved Remedial Design Workplan, and shall submit each of the items described in the Remedial Design Workplan, including, but not limited to, each of the items specified in Section VI.C.2 of this SOW.

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Within 120 days of the approval or modification of the Remedial Design Workplan or within 30 days of either approval of permits for use of the POTW or approval of a Treatment System Design Workplan, whichever occurs later, the Settling Defendants shall submit the Remedial Design for review and approval pursuant to Section VII of this SOW.

Contents of the Remedial Design Workplan. The Settling Defendants shall prepare the Remedial Design Workplan that specifies and describes in detail all activities to be accomplished to support development and design of the leachate collection and groundwater extraction system and treatment system required by the ROD. This workplan shall include plans and procedures for all pilot tests, field studies, modeling and other analysis necessary to ensure the effectiveness of the remedial action required by the ROD. The Remedial Design Workplan shall contain a detailed description, a statement of purposes and objectives, a description of the specific activities necessary to conduct the study, a schedule for implementation of the activities necessary for the development and completion of the Remedial Design, including a schedule for submission of design plans in the Section VI.D.2.b-d of this SOW. The Remedial Design Workplan shall, at a minimum, include the following components:

a. A detailed Project Operation Plan (POP) for all field work to be conducted. The POP shall include, but not be limited to the following:

i. A Site health and safety plan as outlined in Attachment 1, Section A of this SOW;

ii. A quality assurance/quality control plan as outlined in Attachment 1, Section B to this SOW;

iii. A detailed sampling and analysis plan, as outlined in Attachment 1, Section C to this SOW;

iv. Provisions for notification, consultation and reporting to EPA in planning and implementation of all field activities as outlined in Section of the Partial Consent Decree;

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v. A community relations support plan;

vi. A system and schedule for providing to EPA the monthly progress reports required by Section XI of the Partial Consent Decree, and any Site study reports, quality control reports and related field logbooks; and

vii. A Site security plan as outlined in Section IV.C.

viii.An excavation plan for soils excavated in installing the leachate collection system;

ix. A plan for handling excavated soils;

x. A leachate collection, groundwater extraction, and treatment systems operations and maintenance plan;

xi. A Site closure and monitoring plan consistent with Sections V.D and IV.D respectively of this SOW;

xii. A Site security plan consistent with Section V.C of this SOW;

xiii.Provisions for extending the leachate collection system as necessary;

b. Plans and schedule for the following Remedial Design Activities

i. development of detailed designs and specifications in accordance with the following: the ROD; and all Performance Standards including, but not limited to those identified in the ROD, this SOW, and Paragraph 12 of the Partial Consent Decree.

ii. submittal of plans and specifications at the 30%, 60%, 95%, and 100% completion stages, described in Section VI.C.2.a.i-iv below. Each design submission shall provide the assumptions, calculations, drawings and specifications consistent with the SOW and the Workplans approved thereunder.

a) Preliminary design addressing approximately 30% of the total

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remedial design for each component of the remedial action as described in the ROD and this SOW, which shall include at a minimum:

1) a definition of technical requirements for the Work;

2) data and documentation to support each component of the Work;

3) organization of technical specifications and construction drawings; and

4) preliminary design calculations.

b) Intermediate design addressing approximately 60% of the total design for each component of the remedial action described in the ROD and this SOW, including minimum design plans and specifications consistent with Section VI.C.2.a.i of this SOW.

c) Pre-final design addressing 95% of the total desicfns for each component of the remedial action described in the ROD and this SOW, which shall include, at a minimum:

1) corrected design drawings and calculations with written comments to define corrections and/or additions made to the 60% design plans;

2) final specifications and calculations; and

3) a draft Implementation Plan consistent with VI.C.2.b of this SOW;

d) A final design addressing 100% of the total design for each component of the remedial action for review and approval as described in the ROD and

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this SOW. The final design plans shall be provided on reproducible mylars and shall have appended a final Implementation Plan consistent with Section VI.C.2.b of this SOW.

3. Contents of the Remedial Design. The Remedial Design shall be the data, calculati

UNITED STATES ENVIRONMENTA PROTECTIOL N AGENCYPaula Lia Fitzsimmons ME & VT Superfund Section HPS--CAN1 JFK Federal Building Boston, MA 02203 (617) 573-5784 The factual an d legal

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