BROOKHAVEN NATIONAL LABORATORY
OPERABLE UNIT I
AND RADIOLOGICALLY CONTAMINATED SOILS
(INCLUDING AREAS OF CONCERN 6, 8, 10, 16, 17, AND 18)
BROOKHAVEN NATIONAL LABORATORY
UPTON, NEW YORK 11973
This decision document presents the selected remedial actions for Operable Unit I, other Areas of Concern (AOCs) with radiologically contaminated soils and wetland areas with contaminated sediments at the Brookhaven National Laboratory (BNL) site in Upton, New York. It also serves as documentation for the final remedy for removal actions that either have been completed or are ongoing. These remedial actions were selected in accordance with the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) as amended by the Superfund Amendments and Reauthorization Act of 1986 (hereinafter jointly referred to as CERCLA), and is consistent with the National Oil and Hazardous Substances Pollution Contingency Plan (National Contingency Plan), to the extent practicable. This decision is based on the Administrative Record for the BNL site. The State of New York concurs with the selected remedial actions.
Actual or potential releases of hazardous substances including chemical and radioactive materials from these areas may present a threat to public health, welfare, or the environment if they are not addressed by implementing the response actions selected in this Record of Decision.
DESCRIPTION OF THE SELECTED REMEDIES
Operable Unit I is one of the six Operable Units at the BNL site. Operable Unit I includes areas (AOCs 1,2,3, 24E and 24F) where waste was historically managed or disposed of at the site. The main remaining problem is radiologically contaminated soils and sediment. Remedies for other Operable Units are, or will be, selected in other Records of Decisions. This Record of Decision documents remedies which are consistent with the overall site cleanup strategy. Remedies have been identified for areas containing radiologically contaminated soils and sediments, and several other minor Areas of Concern. Removal actions for some Areas of Concern in Operable Unit I were taken to stabilize environmental problems and accelerate cleanup. These removal actions are adopted as final actions. The Record of Decision includes a description of principal contaminants and their representative risks. Cleanup goals have been established to meet regulatory standards. In the absence of Applicable or Relevant and Appropriate Requirements, risk based objectives based on current and future land uses were adopted and are included in this Record of Decision. The costs for each remedy have been estimated and are also included in this Record of Decision.
The major components of the selected remedies are:
In addition, several removal actions that either have been completed or are ongoing are being selected as final remedies. Each was selected in an Action Memorandum and subject to public participation.
Groundwater contamination associated with the Former Landfill Area (AOC 2) and off-site groundwater associated with other Operable Unit I AOCs will be addressed in the Operable Unit III Record of Decision. An evaluation of remedial alternatives for contaminated soil and groundwater associated with the Brookhaven Linear Accelerator Isotope Producer (BLIP) facility (AOC 16K) is underway. The final remedy for this AOC will be documented in a subsequent Record of Decision.
The selected remedies are protective of human health and the environment, comply with federal and state requirements that are legally applicable or relevant and appropriate to the remedial action, and are cost-effective. These remedies use permanent solutions and alternative treatment technologies to the maximum extent practical for this site. However, because treatment of the principal threats of the site associated with radiologically contaminated soils was not found to be practical, these remedies do not satisfy the statutory preference for treatment as a principal element.
Since these remedies will result in hazardous substances remaining on-site above health- based levels for unrestricted use, a review will be conducted every five years after the commencement of remedial action to ensure that the remedies continue to provide adequate protection of human health and the environment.
George J. Malosh
Manager, Brookhaven Group
U.S. Department of Energy
Robert P. Gordon
Contracting Officer, Brookhaven Group
U.S. Department of Energy
Jeanne Fox
Regional Administrator, Region 2
U.S. Environmental Protection Agency
I. DECLARATION OF THE RECORD OF DECISION
II. DECISION SUMMARY
III. RESPONSIVENESS SUMMARY
Table 1 - Description of Operable Units at BNL
Table 2 - Summary of Site History
Table 3 - Groundwater Standards, Guidance Values and Cleanup Goals for Selected Parameters
Table 4 - Soil Remediation Goals for Principal Radiological Contaminants at BNL
Table 5 - Soil Remediation Goals for Principal Chemical Contaminants at BNL
Table 6 - Comparative Analysis of Remedial Alternatives for Radiologically Contaminated Soils
Table 7 - Summary of Selected Remedies
Table 8 - Cost Estimates for Remedial Alternatives
Figure 2 - Record of Decision - Areas of Concern
Figure 3 - OU I Areas of Concern
Figure 4 - Operable Unit I - Radiologically Contaminated Soils
Figure 5 - Actions covered under the OU I Record of Decision
Figure 6 - Principal Areas of Contamination within the HWMF
ALARA - As Low As Reasonably Achievable
AOC - Area of Concern
ARAR - Applicable or Relevant and Appropriate Requirement
BLIP - Brookhaven LINAC Isotope Producer
BNL - Brookhaven National Laboratory
CERCLA - Comprehensive Environmental Response Compensation & Liability
Act
DOE - United States Department of Energy
EE/CA - Engineering Evaluation/Cost Analysis
EPA - United States Environmental Protection Agency
HWMF - Hazardous Waste Management Facility
IAG - Interagency Agreement
MCL - Maximum Contaminant Level
mg/kg - Milligrams per kilogram
mrem/yr - Millirem per year (rem is a measure of human exposure to radiation)
NEPA - National Environmental Policy Act
NYCRR - New York State Codes, Rules and Regulations
NYS - New York State
NYSDEC - New York State Department of Environmental Conservation
OU - Operable Unit
PAH - Polycyclic Aromatic Hydrocarbon
PCB - Polychlorinated Biphenols
PCE - Tetrachloroethene
pCi/g - Picocuries per gram
pCi/l - Picocuries per liter
RCRA - Resource Conservation and Recovery Act
RESRAD - Residual Radioactive Material Guideline Computer Code
SCDHS - Suffolk County Department of Health Services
SPDES - State Pollutant Discharge Elimination System
SVOC - Semi-Volatile Organic Compound
TAGM - NYSDEC Technical Assistance Guidance Memorandum
TBC - To Be Considered
TCA - 1,1,1-trichloroethane
TCE - Trichloroethane
ug/l - Micrograms per liter
VOC - Volatile Organic Compound
1. SITE NAME, LOCATION, AND DESCRIPTION
Brookhaven National Laboratory (BNL) is a federal facility owned by the U.S. Department of Energy (DOE). BNL conducts research in physical, biomedical-and environmental-sciences, and energy technologies.
BNL is located in Upton, Suffolk County, New York, about 60 miles east of New York City, near the geographic center of Long Island (Figure 1). The following are the distances to neighboring communities from BNL: Patchogue 10 miles west-southwest, Bellport 8 miles southwest; Center Moriches 7 miles southeast; Riverhead, 13 miles east; Wading River, 7 miles north-northeast; and, Port Jefferson, 11 miles northwest.
The BNL property, consisting of 5,320 acres, is an irregular polygon, each side approximately 2.5 miles long. The developed portion includes the principal facilities located near the center of the site, on relatively high ground. These facilities are in an area of approximately 900 acres, 500 acres of which were originally developed for the Army’s use. The remaining 400 acres are occupied, for the most part, by various large research machine facilities. Outlying facilities occupy approximately 550 acres and include an apartment area, Biology Field, Hazardous Waste Management Area, Sewage Treatment Plant, fire breaks, and the Landfill Area. The terrain is gently rolling, with elevations varying between 40 to 120 feet above sea level. The land lies on the western rim of the shallow Peconic River watershed, with a tributary of the river rising in marshy areas in the northern section of the tract.
The sole-source aquifer beneath BNL encompasses three water-bearing units: the glacial moraine and outwash deposits, the Magothy Formation, and the Lloyd Sand Member of the Raritan Formation. These units are hydraulically connected and make up a single zone of saturation with varying physical properties extending from a depth of 45-to 1,500-feet below the land surface. These three water-bearing units are designated as a "sole-source aquifer" by the U.S. Environmental Protection Agency (EPA), and serve as the primary source of drinking water for Nassau and Suffolk Counties.
To effectively manage remediation of the BNL site, 29 Areas of Concern (AOCs) were identified and divided into discrete groups called Operable Units (OUs), and Removal Action Areas of Concern. The BNL site is divided into six Operable Units (Table 1).
This Record of Decision addresses OU I and areas of concern 6, 8, 10, 16, 17, and 18 as shown in Figures 2, 3, 4 and 5. These areas contain radiologically contaminated soils; an ash pit, the Recharge Basin HS and the Weaver Drive Recharge Basin HW, the Upland Recharge/Meadow Marsh and the Wooded Wetland, and areas of concern that have been, or are being addressed as removal actions.
2. SITE HISTORY AND ENFORCEMENT ACTIONS
The BNL site, formerly Camp Upton, was occupied by the U.S. Army during World Wars I and II. Between the wars, the site was operated by the Civilian Conservation Corps. It was transferred to the Atomic Energy Commission in 1947, to the Energy Research and Development Administration in 1975, and to DOE in 1977.
In 1980, the BNL site was placed on New York State’s Department of Environmental Conservation (NYSDEC) list of Inactive Hazardous Waste Sites. On December 21, 1989, the BNL site was included on EPA’s National Priorities List because of soil and groundwater contamination that resulted from BNL’s past operations. Subsequently, the EPA, NYSDEC, and DOE entered into a Federal Facilities Agreement (herein referred to as the IAG) that became effective in May, 1992 (Administrative Docket Number: II-CERCLA-FFA-00201) to coordinate cleanup activities. The IAG identified areas of concern that were subsequently grouped into Operable Units to be evaluated for response actions. The IAG requires a remedial investigation/feasibility study for OU I, pursuant to 42 U.S.C. 9601 et. seq., to meet CERCLA requirements. The IAG also requires cleanup actions to address the identified concerns. Cleanup actions at the BNL site will be conducted pursuant to CERCLA, 40 CFR Part 300.
BNL’s Response Strategy Document (SAIC, 1992) grouped the identified areas of concern into seven Operable Units. Several Operable Units were subsequently combined. Remedial investigations (CDM Federal 1996a; IT 1999) and risk assessments were conducted to evaluate the nature and extent of contamination, and the potential risks associated with the areas of concern addressed in this Record of Decision. A Feasibility Study (CDM Federal 1999) was prepared to evaluate the alternatives for remediating the radiologically contaminated soils and other areas of concern addressed in this Record of Decision. In addition, several accelerated cleanup actions were taken as discussed in Section 2.3, and an interim action was taken at the Building 650 Sump Outfall Area. The Sump Outfall Area was fenced off to prevent unnecessary access.
2.1 Radiological Contaminated Soil Sites
There are several areas throughout the BNL site where the soil has become contaminated with radionuclides from past waste handling operations, spills, or inadvertent use of contaminated soils for landscaping (Figure 4). The majority of the radioactively contaminated soils are located at the former Hazardous Waste Management Facility. These areas are discussed in Table 2.
2.2 Other Areas of Concern
There are five other areas of concern that are being addressed by this Record of Decision. They are the Upland Recharge/Meadow Marsh Area, Recharge Basin HS and the Weaver Drive Recharge Basin HW and Weaver Drive Recharge Basin, Ash Pit, and the Wooded Wetland. A discussion of these areas is presented in Table 2.
2.3 Removal Actions
DOE determined that accelerated cleanup actions, called removal actions, were required for several areas of concern. The potential removal actions were evaluated in Engineering Evaluation/Cost Analysis Reports that were prepared pursuant to CERCLA (CDM, 1995a; CDM, 1995b; and CDM, 1997a). These reports were made available for public review and were approved by the regulatory agencies. The removal actions selected, after considering public comments, were documented in Action Memoranda (BNL, 1994; BNL, 1996; BNL, 1997).
Several landfill areas of concern were capped to prevent the migration of contaminations. A geomembrane cap, constructed pursuant to 6 NYCRR Part 360, was placed over the Current Landfill, Former Landfill, Slit Trench and Interim Landfill. Construction of the cap was completed in November, 1995 at the Current Landfill; in October, 1996 at the Former Landfill and Slit Trench; and in November 1997 at the Interim Landfill. Details are documented in the construction certification reports (CDM, 1996b; Weston, 1997; and Grosser, 1997). The National Weather Service’s soil stockpile was used as fill on the Former Landfill before placement of the cap. A 55-gallon drum containing soil with levels of radionuclides greater than cleanup levels is stored at the former HWMF awaiting off-site disposal.
Contaminated soil, debris, animal remains, laboratory equipment, and intact chemical bottles were excavated and segregated for treatment and/or disposal from the Chemical/Animals Pits and Glass Holes. Soil samples were taken at each pit to ensure that all hazardous materials were removed and cleanup levels were met.
Several actions are being taken to address groundwater contamination resulting from waste-disposal activities at the former HWMF and the Current Landfill. A groundwater pump- and-treat system was installed in December 1996 at BNL’s southern boundary to extract and treat on-site groundwater contaminated with Volatile Organic Compounds (VOCs) downgradient of OU I source areas. The groundwater is recharged upgradient into a recharge basin. Groundwater in this area is being monitored. Institutional controls will prevent supply wells or other pumping wells being installed that may mobilize remaining contaminants or otherwise interfere with the remedial actions. Groundwater contamination associated with the Former Landfill, and contaminated groundwater that has migrated off-site will be addressed in the remedies for Operable Unit III.
These removal actions are being adopted as final actions in this Record of Decision. They will be monitored and maintained.
3. HIGHLIGHTS OF COMMUNITY PARTICIPATION
A Community Relations Plan was finalized for the BNL site in September, 1991. In accordance with this plan and CERCLA Sections 113 (k) (2)(B)(I-v) and 117, the community relations program focused on public information and involvement. A variety of activities provide information and seek public participation, including a stakeholders’ mailing list, community meetings, availability sessions, site tours, workshops, and fact sheets. An Administrative Record was established, documenting the basis for selecting the removal and remedial actions at the BNL site, and it is maintained at the local libraries listed below. These libraries also maintain current site-reports, press releases, and fact sheets.
Longwood Public Library
800 Middle Country Road
Middle Island, NY 11953
Mastics-Moriches-Shirley Community Library
301 William Floyd Parkway
Shirley, NY 11967
Brookhaven National Laboratory Research Library
Bldg. 477A
Upton, NY 11973
The Administrative Record also is kept at EPA's Region II Administrative Records Room, 290 Broadway, New York, NY, 10007-1866.
Consistent with CERCLA guidance and state requirements, community involvement and participation was solicited for all significant documents and decisions associated with this Record of Decision. The final scope of work, the work plan, quality assurance plan, the engineering evaluation/cost analysis documents for the removal actions, risk-assessment documents, remedial investigation reports, the proposed plan, and the feasibility study were made available for public review.
The latest community involvement activities included the review of the OU I Feasibility Study (CDM, 1999a) and Proposed Plan (BNL, 1999). In April 1999, a public notice was published in Newsday and Suffolk Life announcing the availability for review and comment of the OU I Feasibility Study and Proposed Plan, dates of information sessions, and a public meeting date. A Press Release also was issued. Public comment began April 1, 1999 and ended on April 30, 1999. A mailing was sent to the Community Involvement mailing list (2300 homes) which included a fact sheet on the Feasibility Study and Proposed Plan and a copy of the public notice. Information sessions were held on April 13, 1999 and April 14, 1999, and a public meeting was held on April 22, 1999. An article about OU I was published in BNL’s quarterly newsletter cleanupdate in December, 1999, and an article was published in the Brookhaven Bulletin in April 1999. Display advertisements listing the dates of the public comment period, information sessions, and the public meeting were placed in Suffolk Life and Newsday.
4. SCOPE AND ROLE OF OPERABLE UNIT AND RESPONSE ACTION
To adequately evaluate existing and potential environmental problems at BNL, the 29 areas of concern were grouped into six Operable Units. The scope of these Operable Units is shown in Table 1. The Operable Units were established under the Response Strategy Document (SAIC, 1992) based on six criteria: (1) relative proximity of the areas of concern, (2) similar problems, (3) similar phases of action or sets of actions, (4) simultaneous actions, (5) absence of interference with future actions, and (6) similar geology and hydrology.
This Record of Decision selects remedial actions for OU I and areas of concern 6, 8, 10, 16, 17, and 18. Radiologically contaminated soil is the principal threat addressed. The majority of the radiologically contaminated soil containing the highest contaminant levels is located at the former HWMF. Radiologically contaminated soil poses a risk to human health and ecological receptors from exposure to waste-site contaminants and from the potential for contaminants to migrate to surface water, wetlands, and groundwater.
The Upland Recharge/Meadow Marsh Area requires action to address the potential threat to the Tiger Salamander from chemical contaminants (i.e. metals) in these areas. The Tiger Salamander is a New York State endangered species. The Wooded Wetland will be monitored to assure that remnant contaminants from the Current Landfill will not contaminate the wetland. The principal threat at the Ash Pit is human exposure to lead in soil.
The completed and ongoing removal actions address on-site Volatile Organic Compounds in groundwater and buried wastes in landfills. Groundwater contamination associated with the Former Landfill Area (AOC 2) and off-site groundwater associated with other Operable Unit I AOCs will be addressed in the Operable Unit III Record of Decision.
Conducting this remedial action under OU I is part of BNL’s overall response strategy and is expected to be consistent with any planned future actions and actions taken at the other Operable Units, which are at different phases of the CERCLA process.
5. SUMMARY OF SITE CHARACTERISTICS
The following sections summarize the site characteristics of the various areas of concern addressed by this Record of Decision. Various investigations were undertaken to evaluate the nature and extent of contamination. A combination of investigation approaches were utilized including (1) radiation surveys, (2) soil-vapor surveys, (3) soil borings/soil sampling, (4) monitoring well installation and groundwater sampling, (5) groundwater modeling, (6) sediment/surface water sampling, and (9) geophysical investigations. The areas investigated were the landfills, Ash Pit, Chemical/Animal Pits and Glass Holes, the former Hazardous Waste Management Facility, the Waste Concentration Facility, Reclamation Facility and other areas of concern. Information on the site’s characteristics also was obtained through implementing of the various removal actions.
5.1 Radiologically Contaminated Soils
The former Hazardous Waste Management Facility Area of Concern contains the majority of the radioactively contaminated soil. The soil became contaminated with radionuclides and mercury due to several spills of hazardous and radioactive materials during operations at the facility. The predominant radionuclide found is cesium-137, which emits beta- and gamma-radiation, and is the primary source of risk from direct exposure. Strontium-90, which emits beta radiation, also is present. Both radionuclides are relatively short-lived, with half-lives of 30-and 28-years, respectively. The maximum levels detected during remedial investigations was 810,000 picocuries per gram (pCi/g) for cesium-137, and 1,300 pCi/g for strontium-90.
Most of the contamination in this area is at, or near, the surface, although in some locations it extends to 12 feet below the surface. Approximately 35,000 cubic yards of contaminated soil is anticipated to require remediation at the former Hazardous Waste Management Facility out of a total of 39,500 cubic yards for all radiologically contaminated sites. Figure 6 illustrates the principal areas of surface contamination, and relative concentrations within the facility, based on radiation surveys and surface-soil sampling. There is no significant widespread chemical contamination of soil within the former Hazardous Waste Management Facility, except for isolated locations where low concentrations of mercury of 184 mg/kg (maximum concentration), lead (maximum concentration of 429 mg/kg) and other metals were detected. Mercury and lead are the only chemical constituents present that require remedial action.
Radiological contaminated surface soils also were found at several locations throughout the site (AOC 16, 17, and 18). The contamination resulted from the use, handling, and storage of activated materials or the use of slightly contaminated landscaping soil. Soils contaminated with low levels of radionuclides from the former Hazardous Waste Management Facility were inadvertently used as landscaping material outside several buildings. The dominant radionuclide found in these locations is cesium-137, with a maximum concentration of 348 pCi/g at AOC 16E (near building 490). One area (AOC 16 S.3) contained elevated lead at 2,310 mg/kg.
The soils at the Waste Concentration Facility became contaminated with radionuclides as a result of leaks from a tank. The primary contaminants are cesium-137, with a maximum concentration of 1,486 pCi/g and strontium-90 with a maximum concentration of 454 pCi/g. Radionuclides were detected in soil samples to a depth of 12 feet. There are no chemical constituents present that require remedial action. In addition to soils, the Waste Concentration Facility includes liquid-waste transport lines and an enclosed concrete vault. The above-ground ‘D’ tanks have been removed in a separate removal action. However, six underground tanks containing radioactive sludge remain.
The Reclamation Facility (Building 650) was used to decontaminate radiological- contaminated clothing and equipment. Soils near this facility and the sump-outfall area have become contaminated from the activities conducted at this facility. Several radionuclides exceed the soil cleanup goals. Table 2 identifies the primary contaminants of concern and the maximum concentrations.
5.2 Other Areas of Concern
The Ash Pit, which received ash and slag from a solid-waste incinerator, contains lead above cleanup goals. Radionuclides were detected at background levels. The Upland Recharge/Meadow Marsh Area contains low levels of pesticides and metals. The Recharge Basin HS and the Weaver Drive Recharge Basin HW that receive stormwater effluent operate in accordance with a New York State Pollution Discharge Elimination System permit. No contaminants were found at levels that would impact public health; however, Tiger Salamanders, a New York endangered species, have been found in both basins. The Wooded Wetland received drainage from the Current Landfill containing metals below levels of concern for human health.
5.3 Removal Actions
Groundwater beneath the Current Landfill and the former HWMF is contaminated with radionuclides, Volatile Organic Compounds, and metals above maximum contaminant levels (MCLs). The currently operating pump and treat system described in Section 2 is removing the Volatile Organic Compounds. The portion of the plume that has moved off-site will be addressed in the OU III Record of Decision.
The contaminants of concern that were dealt with by capping the Current and Former Landfills are identified in the Landfills Engineering Evaluation/Cost Analysis Report (CDM, 1995a). The Chemical/Animal Pits and Glass Holes, which were excavated in 1997, contained buried wastes and low levels of solvents, metals, and radionuclides that required remediation. These areas are summarized in Table 2.
6. SUMMARY OF SITE RISKS
The risks associated with the Chemical/Animal Pits and Glass Holes were considered through Engineering Evaluation/Cost Analysis process. Risk assessments are not given for the landfill removal actions which are presumptive remedies. Risk assessments were conducted for several areas of radiologically contaminated soils, groundwater and other areas of concern.
A four-step process was used for assessing site-related human-health risks within a reasonable maximum exposure scenario:
Human health risks were evaluated for exposures to radiological and chemical contaminants of concern. The chemical Risk Assessment addressed the risk of cancer and non-carcinogenic toxicity. The health risk of concern from radionuclides is cancer. Current federal guidelines for acceptable exposures are: 1) an individual lifetime excess carcinogenic risk in the range of a one-in-ten-thousand (1x10-4) to one in-a-million (1x10-6), and 2) a maximum health Hazard Index equal to 1.0, which reflects non-carcinogenic effects. A Hazard Index greater than 1.0 indicates a potential for non-carcinogenic health effects. For radiological risks, EPA’s guidance of 15 mrem/yr exposure is consistent with the acceptable risks range (EPA, 1997).
6.1 Human Health Risks
Chemicals of potential concern were selected based on procedures specified in EPA's Risk Assessment Guidance for Superfund, Part A (EPA, 1989). Contaminants evaluated in the risk assessment exceeded screening levels based on their degree of toxicity, concentration, frequency of detection, chemical properties important to potential release, transport, and exposure, and significant exposure routes. Table 2 identifies the primary contaminants of concern.
Present and potential future-use scenarios were quantitatively evaluated for the following receptor populations:
The areas evaluated included:
The environmental media evaluated in the risk assessment, as applicable to specific areas, land use scenarios and exposure pathways included:
The toxicity assessment consisted of examining the toxicological properties of selected chemicals of potential concern using the most current data on human-health effects. Many of the chemical carcinogenic slope-factors and reference doses used were obtained from EPA's Integrated Risk Information System data base. Those not available in that data base were obtained from EPA's second most current source of toxicity information, Health Effects Assessment Summary Tables. Radiological slope-factors developed by EPA were used to assess radiological risks. The potential health hazards from exposure to non-carcinogens was determined by comparing the estimated chronic or subchronic daily intake of a chemical with the risk reference dose. When toxicity values were not available for a specific chemical, its effects were qualified. Uncertainties in the toxicity data were evaluated.
For carcinogenic chemical contaminants, only groundwater presented an unacceptable risk. For the OU I/VI ethylene dibromide (EDB) plume, future residential carcinogenic risks were 2.7 x 10-4 (2.7 in 10,000) for adults and 1.6 x 10-4 for children for groundwater ingestion and were largely due to ethylene dibromide. The 30-year combined risk for adults and children was 4.3 x 10-4. For the former HWMF/Current Landfill Plume, the 30-year combined risk for adults and children for future residential ingestion was 1.6 x 10-4. The principal risk drivers for this plume were ethylene dibromide, 1,1-dichloroethylene, vinyl chloride, arsenic and beryllium.
For non-carcinogenic chemical contaminants in groundwater, hazard index values for adult and child ingestion of groundwater from the former HWMF/Current Landfill plume were 2.6 and 6.1 and were due primarily to manganese and thallium. The hazard index value for child ingestion of groundwater from the OU I/VI EBD plume was 1.2 and was due primarily to the presence of manganese.
Accelerated actions were taken to address these plumes. A pump-and-treat system was installed to treat VOC-contaminated groundwater from the former HWMF/Current Landfill Plume and is contained in this Record of Decision. The OU I/VI EDB plume was addressed in a separate focused feasibility study and Record of Decision.
For non-carcinogenic chemical contaminants in surface soils, a hazard index of 3.6 was calculated for future soil ingestion by children and was due primarily to mercury. Concentrations of lead at the Former HWMF and the Ash Pit were also above EPA’s recommended soil screening level of 400 mg/kg for residential uses.
Risks from exposure to surface soils contaminated with radionuclides were calculated for the Reclamation Facility (Building 650) Sump and Outfall Area (CDM, 1994). Only, the risk estimates for potential future residents (combined adults and children) exceeded EPA’s target risk range in both areas with a maximum risk of risk of 4.3 x 10-3 (4.3 in 1,000) (or 5.3 x 10-3 when alpha activity is assumed to measure uranium-235). The risk was due almost entirely to the external gamma radiation pathway with the major contributors being cesium-137 and uranium-235. Using the higher concentrations found in the May 1994 sampling, the future residential risk was about one order of magnitude higher, i.e. in the 10-1 to 10-2 (1 in 10 to 1 in 100) range. Risks to on-site workers using the 1994 data was also one order of magnitude higher.
Radiological risks at the former HWMF were not calculated because this facility is a restricted area and an active handling facility for hazardous and radioactive wastes (CDM, 1996a). Levels of contamination in soils were high and remediation was assumed to be required. Current public access and exposure to contaminants in this area is not realistic since there are stringent institutional controls restricting access for the foreseeable future. A radiological worker protection program and procedures protect current site workers. Since concentrations of contaminants in soil are greater at the former HWMF than at the Reclamation Facility, potential future residential risks would also be greater at the former HWMF than the risks described above at the Reclamation Facility.
Radiological risks for AOCs 10, 16, 17 and 18 were evaluated by comparing contaminant concentrations to cleanup levels developed using a future residential land use and EPA’s cleanup goal of 15 mrem/yr. (IT, 1999) AOC 10 and six of the AOC 16 sites were above the 15 mrem/yr goal for future residential land use. AOCs 17, 18 and the remaining sites from AOC 16 were below the 15 mrem/year goal for future residential land use. Risks to current site workers and the public at these areas are controlled by institutional controls, such as fencing, where needed.
Post remediation risks at all areas of concern will meet EPA’s acceptable risk range.
6.2 Ecological Risk Assessment
A standard ecological risk assessment (as prescribed by the EPA) consists of a four-step process used for assessing ecological risks for a reasonable maximum exposure scenario:
A Preliminary Ecological Risk Screening was performed (CDM, 1996a). That identified the need for a focused ecological-risk assessment at the former HWMF wetland, the Wooded Wetland adjacent to the Current Landfill, Recharge Basin HS, Weaver Drive Recharge Basin HW, and the Upland Recharge/Meadow Marsh Area due to the presence of the Tiger Salamander which is an endangered species in New York State.
The Focused Ecological Risk Assessment and Addendum (CDM, 1999a and 1999b), evaluated potential toxicity risks to the Tiger Salamander in these areas of concern. The assessment concluded that there was an exposure risk associated with various metals for larval salamanders living in the water at each of the areas of concern investigated except the Weaver Road Recharge Basin HW. Aquatic indices calculated for larval salamanders were 26 at the former HWMF wetland due primarily to aluminum, 2,341 at the Upland Recharge/Meadow Marsh due primarily to copper and zinc, and 368 at Recharge Basin HS due primarily to aluminum. For the Wooded Wetland, a comparison of the hazard indices calculated from 1994 to 1997 data showed a reduction in the hazard index from 830 to 23; both were due primarily to aluminum. The Current Landfill cap is designed to reduce impacts from leachate from the Current Landfill on this wetland.
7. OBJECTIVES OF THE REMEDIAL ACTION S
The following sections identify the basis for taking remedial actions, the objectives of the remedial actions, land-use considerations, and cleanup goals for the radiologically contaminated soil sites and the other areas of concern.
The objectives of the removal actions were addressed in the various Engineering Evaluation/Cost Analysis Reports and Action Memoranda specific to the action. The Current Landfill, Former Landfill, Slit Trench and Interim Landfill were capped in accordance with EPA’s presumptive remedy guidance for municipal landfills (OSWER Directive No 93555.0-49) and State guidance (TAGM No. HWR-92-4044). Buried wastes and contaminated soils were removed from the Chemical/Animal Pits and Glass Holes. New York State guidance levels (TAGM No. HWR-94-4046) which are protective of groundwater and residential land use were used for soil cleanup levels for Volatile Organic Compounds. State guidance levels were also used for cadmium and chromium. The cleanup levels used for lead and mercury are listed in Table 5 and are based on EPA soil screening level guidance. Cleanup levels for radionuclides used the industrial land use levels contained in Table 4. These cleanup levels meet EPA’s acceptable risk range.
7.1 Basis for Response
The actual or threatened releases of hazardous substances from OU I may present an imminent and substantial endangerment to public health, welfare or the environment if they are not addressed by implementing the remedial actions selected in this Record of Decision. The principal threat is cesium-137 in the soil. There also is the potential for strontium-90 to migrate from the soil into the underlying sole-source aquifer.
7.2 Objectives of the Remedial Action s
The following objectives for remedial action were established for the radiologically contaminated soils and other areas of concern:
7.3 Land Use
Specific cleanup goals (i.e. acceptable contaminant levels) have been identified to achieve the objectives identified above. Cleanup goals are based primarily on Applicable or Relevant and Appropriate Requirements (ARARs), EPA and State guidance in combination with an evaluation of land use. BNL is currently used by DOE as a research facility with associated support facilities and is expected to remain so for the forseeable future. Access to the BNL site is currently restricted and controlled.
A future land use study was undertaken and published by BNL in 1995 (BNL 1995). Potential land uses that could occur after BNL closes as a national laboratory were identified as a mix of open space, industrial/commercial, recreational and residential uses. For the purposes of developing radionuclide cleanup goals for OU I, a future industrial use was assumed for the former HWMF, as opposed to the recreational and open space uses identified in the 1995 study, to give greater flexibility for potential future uses. A future residential use was identified in the OU I Feasibility Study for AOCs 6, 10, 16, 17 and 18 even though these AOCs are in the developed portion of BNL. This approach was taken since the volumes of contaminated soil are smaller and it is cost effective to use a lower cleanup level. This will also allow greater flexibility in future uses at these AOCs.
An institutional control period of 50 years was also assumed. This is the time period after which BNL might be available to the public for use.
7.4 Cleanup Goals
The cleanup goal or level established for radionuclides in soil is based on a total dose limit of 15 mrem/yr above background (EPA, 1997). EPA’s acceptable risk range will also be met upon the completion of remedial action. Cleanup levels for specific radionuclides were calculated using the DOE Residual Radioactive Material Guidelines (RESRAD) computer code, 15 mrem/yr, the assumed future land use and 50 years of continued DOE control. Examples for cesium-137 are given in Table 4. The potential for the contaminated soil to impact groundwater is also considered. A cleanup level for strontium-90 was calculated based on potential impacts to groundwater and is also listed in Table 4. This level is also protective of both residential and industrial uses. A 5 pCi/g cleanup level was also selected for radium-226 based on DOE Order 5400.5. This level is also commonly used by EPA. Post remediation sampling and dose assessments will be performed to ensure that the 15 mrem/year limit will be met for all radionuclides that remain. The NYSDEC guidance of 10 mrem/yr above background has been adopted as an As Low As Reasonably Achievable (ALARA) goal which will be considered during the design and construction phase.
While radionuclides are the primary contaminants of concern in soils, some chemical contamination also exists. Chemical cleanup levels are listed in Table 5. A cleanup level of 1.84 mg/kg for mercury was selected for the former HWMF. This level was calculated using EPA’s soil screening level guidance (OSWER 9355.4-23) and is protective of groundwater and a residential use. A cleanup level of 400 mg/kg for lead was also selected for the Ash Pit, the former HWMF and AOC 16 S.3 based on EPA’s soil screening level guidance. This level is protective of a residential use.
Cleanup goals for groundwater contaminants are based on an evaluation of Federal and State MCLs and groundwater standards (Table 3). Groundwater treatment will continue until either the cleanup goals are met in the groundwater or the following performance objective is met. If monitoring indicates that continued operation of the groundwater treatment system is not producing significant reductions in the concentrations of contaminants in the groundwater and concentrations are still above the cleanup goals listed in Table 3, then DOE, NYSDEC and EPA will evaluate whether operation of this system can be discontinued in accordance with the National Contingency Plan (NCP). The criteria for discontinuation will include an evaluation of the operating conditions and parameters as well as a determination that the groundwater system has attained the feasible limit of contaminant reduction and that future reductions would be impractical.
8. DESCRIPTION OF ALTERNATIVES
Section 121 of CERCLA requires that each selected remedy protects human health and the environment, is cost effective, complies with other statutory laws, and uses permanent solutions, alternative treatment technologies, and resource-recovery alternatives as fully as practicable. In addition, the statute includes a preference for treatment as a principal way of reducing the toxicity, mobility, or volume of the hazardous substances.
This section summaries the remedial alternatives evaluated for the radiologically contaminated soil sites and other areas of concern addressed by this Record of Decision. Details of the alternatives are given in the Final OU I and Radiologically Contaminated Soils Feasibility Study Report (CDM, 1999a). Several technologies, in addition to those described below, were evaluated and screened from further consideration. Technologies that include processes such as chemical separation, encapsulation, chemical treatment, and phytoremediation, were considered not to be effective.
To evaluate remedial alternatives, information is needed related to future land use and the cleanup standards. For all areas except the former HWMF, residential land use and corresponding cleanup goals, as identified in Section 7, were assumed. Industrial land use cleanup goals were assumed for the former HWMF (Section 7). For some of the alternatives evaluated where contaminated soils will be left on-site, it was necessary to set a secondary action level to determine which soil may require additional treatment or disposal (the principal threat was waste). Cesium-137 was the primary radiological contaminant for all the soils; therefore, the secondary action level is based on this constituent. In the event that institutional controls failed and an inadvertent intruder built a dwelling near to the radiological soil left on-site (e.g., above a capped or engineered cell), the secondary-action level would ensure that the exposure to this waste was not in excess of 75 mrem/yr. Based upon these considerations, this secondary-action level was set at 600 pCi/g of cesium-137.
To estimate costs for the alternatives presented below, assumptions about the institutional control period were developed. This period is assumed to be 100 years, except for radiological contaminated soil alternative 4, where a 50-year institutional control period is assumed. Other common elements for the radiologically contaminated soil alternatives include reconstructing the former HWMF wetland after remediation for all alternatives except alternative 1. Structures (such as pipes, foundations, and tanks) at the Reclamation Facility ( Building 650 Sump and Outfall Area) and the Waste Concentration Facility will also require removal to access the contaminated soils. Some buildings at the former HWMF also must be removed to gain access to contaminated soils.
8.1 Radiologically Contaminated Soils
| Alternative 1: No Action with Monitoring and Institutional Controls | |
| Capital Cost: | $ 52,000 |
| Annual Operation &Maintenance (O&M) Cost: | $ 55,513 |
| Total O&M Cost (present worth): | $792,000 |
| Total Present Worth: | $844,000 |
Under the "No Action" alternative, no remedial action would be taken and the sites would continue in their current state except that a fence would be installed around the former HWMF wetland. Groundwater monitoring and surface-water sampling would be conducted in certain areas. The existing institutional controls would remain in place.
| Alternative 2: Engineered Cell, Monitoring and Institutional Controls | |
| Capital Cost: | $7,487,000 |
| Annual O&M Cost: | $ 81,380 |
| Total O&M Cost (present worth): | $1,161,000 |
| Total Present Worth: | $8,648,000 |
This alternative includes excavating all of the radiologically contaminated soils exceeding the soil cleanup goals, staging most of the soils at the former HWMF, constructing an engineered cell which includes a leachate collection and removal system, a composite cover, placing the contaminated soils in the engineered cell and covering the area with a composite cover. Approximately 35,000 cubic yards of soils from the former HWMF and approximately 3,450 cubic yards of soils from the other radiologically contaminated areas would be excavated that are above soil cleanup levels in Table 4, and disposed in the cell. Soils contaminated with long half-life radionuclides from the Reclamation Facility (Building 650) Sump and Outfall Area (approximately 1,040 cubic yards) would be excavated and disposed off-site. Long-term monitoring of the cover and groundwater would be conducted along with maintaining of the cover. Institutional controls would be put in to place to limit access to the site, to ensure that the cover is not disturbed, and to prevent the installation of drinking-water wells in contaminated groundwater.
| Alternative 3: Moderate Excavation, Off-Site Disposal and RCRA Cap | |
| Capital Cost: | $14,005,000 |
| Annual O&M Cost: | $ 63,710 |
| Total O&M Cost (present worth): | $ 909,000 |
| Total Present Worth: | $14,914,000 |
Alternative 3 involves excavation and off-site disposal of all soils over the secondary action level (600 pCi/g of cesium-137) at the former HWMF. Approximately 14,585 cubic yards of soil and debris will be excavated and disposed off-site. A Resource Conservation and Recovery Act (RCRA) cap will be constructed over the former HWMF soils that are below the secondary action level (19,490 cubic yards). Soils contaminated above the soil cleanup levels with cesium-137 and/or strontium-90 from other areas (approximately 3,450 cubic yards) will be excavated and consolidated under the RCRA cover at the Former HWMF. Approximately 1,040 cubic yards of soils contaminated with long half-life radionuclides from the Reclamation Facility (Building 650) Sump and Outfall Area will be disposed at an off-site facility. Long-term monitoring of the cover and groundwater would be conducted, and the cover maintained. Institutional controls would be put in to place to limit access to the site, to ensure that the cover is not disturbed, and to prevent the installation of drinking water wells in contaminated groundwater.
| Alternative 4: Large Scale Excavation and Off-Site Disposal | |
| Capital Cost: | $23,615,000 |
| Annual O&M Cost: | $ 45,470 |
| Total O&M Cost (present worth): | $ 417,000 |
| Total Present Worth: | $24,032,000 |
Alternative 4 involves excavating of contaminated soils above cleanup goals (industrial goals for former HWMF and residential goals for other areas) and off-site disposal, and monitoring the remaining contaminated soils. A 50-year institutional control period is assumed for cost estimating purposes. Approximately 39,500 cubic yards of contaminated soils would be excavated and staged at the former HWMF. Certain waste will likely required pretreatment (e.g., stabilization, solidifcation) to meet the waste acceptance criteria at the disposal facility. Groundwater monitoring would be conducted in specific areas. Institutional controls would be put in to place to ensure that land uses remain protective of human health, limit access to the site, to ensure that the cover is not disturbed, and to prevent the installation of drinking water wells in contaminated groundwater.
| Alternative 5: Moderate Excavation, Soil Washing, Off-Site Disposal and RCRA Cap | |
| Capital Cost: | $14,395,000 |
| Annual O&M Cost: | $ 63,710 |
| 100-year O&M Cost (present worth): | $ 909,000 |
| Total Present Worth: | $15,304,000 |
Alternative 5 is identical to Alternative 3 in scope, except that all excavated soils with concentrations of radionuclides greater than the secondary action levels (600 pCi/g of cesium-137) and less than 2,800 pCi/g of cesium-137 would be washed on-site to reduce the volume of contaminated material that is shipped off-site for disposal. Approximately 6,030 cubic yards of soil would be washed. The approximately 24,490 cubic yards of soil below the secondary action level of 600 pCi/g of cesium-137 but above the soil cleanup level of 67 pCi/g of cesium-137, together with clean soil from the treatment process, will be consolidated at the former HWMF and capped with a RCRA cap, as described in Alternative 3. With this alternative, approximately 11,404 cubic yards of material will be disposed off-site. Long-term monitoring of the cover and groundwater would be conducted, along with maintenance of the cover. Institutional controls would be put in to place to limit access to the site, to ensure that the cover is not disturbed, and to prevent the installation of drinking-water wells in contaminated groundwater.
| Alternative 6: Moderate Vitrification and RCRA Cap | |
| Capital Cost: | $18,645,000 |
| Annual O&M Cost: | $ 65,710 |
| 100-year O&M Cost (present worth): | $ 909,000 |
| Total Present Worth: | $19,554,000 |
Under Alternative 6, soils from the former HWMF with concentrations greater than the secondary action level of 600 pCi/g cesium-137 (approximately 14,585 cubic yards) and approximately 1,040 cubic yards of contaminated soil with long-lived radionuclides from the Building 650 and the Sump Outfall would be treated by vitrification followed by geomembrane capping. All other soils contaminated above the cleanup goal, but below the secondary action level, would be consolidated at the former HWMF under a geomembrane cap. Long-term monitoring of the cover and groundwater would be conducted along with maintenance of the cover. Institutional controls would be put in to place to limit access to the site, to ensure that the cover is not disturbed, and to prevent the installation of drinking water wells in contaminated groundwater.
8.2 Other Areas of Concern
Three alternatives were evaluated for the Ash Pit (AOC 2F).
| Alternative 1: No Action with Monitoring | |
| Capital Cost: | $ 0 |
| Annual O&M Cost: | $ 2,000 |
| 50-year O&M Cost (present worth): | $ 29,000 |
| Present Worth: | $ 29,000 |
Under the first alternative, no further action would be taken and the Ash Pit would be left in its current status. Long-term monitoring (visual observation of the Ash Pit). A 50-year institutional control period is assumed for cost estimating purposes.
| Alternative 2: Soil Cover | |
| Capital Cost: | $ 117,000 |
| Annual O&M Cost: | $ 2,000 |
| 50-year O&M Cost (present worth): | $ 29,000 |
| Present Worth: | $ 146,000 |
For the second alternative, the Ash Pit would be covered with a 12-inch layer of soil in accordance with EPA guidance. The Ash Pit would be visually inspected to ensure that ash is not exposed at the surface. Institutional controls would be put in place to limit access to the site and prevent disturbance of the soil cover. A 50-year institutional control period is assumed for cost estimating purposes.
| Alternative 3: Excavation with Off-site Disposal | |
| Capital Cost: | $ 3,197,000 |
| O&M Cost (present worth): | $ 0 |
| Present Worth: | $ 3,197,000 |
Alternative 3 would involve excavating and disposing of the 13,960 cubic yards of ash off-site. The area would be backfilled and a portion of the road impacted during remedial construction activities would be replaced.
For the two artificial basins at the Upland Recharge/Meadow Marsh Area, the following three remediation alternatives were evaluated to protect the Tiger Salamander:
| Alternative 1: No Action with Monitoring | |
| Capital Cost: | $ 0 |
| Annual O&M Cost: | $ 3,000 |
| 50-year O&M Cost (present worth): | $ 44,000 |
| Present Worth: | $ 44,000 |
Under the first alternative, no further action would be taken and the current status of the ponds will remain. Long-term ecological monitoring would be performed.
| Alternative 2: Excavation with On-Site Disposal and Reconstruction of the Wetlands | |
| Capital Cost: | $ 184,000 |
| Annual O&M Cost: | $ 3,000 |
| 50-year O&M Cost (present worth): | $ 44,000 |
| Present Worth: | $ 228,000 |
Under the second alternative, water would be removed from the ponds (if necessary) and transported to the BNL wastewater treatment plant, the sediments (1,270 cubic yards) and plastic liners (42 cubic yards) would be removed and placed in an approved on-site clean-fill site. The ponds then would be restored as a wetland. Long-term ecological monitoring would be performed.
| Alternative 3: Excavation with Off-site Disposal and Reconstruction of the Wetlands | |
| Capital Cost: | $ 398,000 |
| Annual O&M Cost: | $ 3,000 |
| 50-year O&M Cost (present worth): | $ 44,000 |
| Present Worth: | $ 442,000 |
Under the third alternative, water would be removed from the ponds (if necessary) and transported to the BNL wastewater treatment plant, the sediments (1,270 cubic yards) and plastic liners (42 cubic yards) would be removed and disposed of off-site at an approved landfill. The ponds would then be restored as a wetland. Long-term ecological monitoring would be conducted.
Alternatives were not evaluated for the Recharge Basin HS and the Weaver Drive Recharge Basin HW because they are operated and monitored according to NYSDEC permits. The basins would continue to be operated, maintained, and monitored in accordance with permit requirements and in a manner to reduce negative impacts to Tiger Salamanders. A Tiger Salamander Habitat Management Plan will be prepared in coordination with the NYSDEC to reduce the impacts of routine maintenance of the basins on the animal.
Alternatives were not evaluated for the Wooded Wetland because sampling conducted before and after the capping of the Current Landfill indicates that the cap is successfully reducing contamination of the Wooded Wetland by landfill leachate. However, surface water and sediments will be monitored annually to ensure the cap remains successful.
9. SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
The CERCLA requires a comparision of each remedial alternative identified in the feasibility study according to nine criteria. Those criteria are subdivided into the following three categories:
(a) Threshold criteria that relate directly to statutory findings and must be satisfied by each chosen alternative (overall protection of human health and the environment and compliance with ARARs);
(b) Primary balancing criteria that include long- and short-term effectiveness; implementability; reduction of toxicity, mobility, volume; and cost
(c) Modifying criteria that measure the acceptability of the alternatives to state agencies and the community.
The following sections summarize the comparative analysis described in the feasibility study for the radiologically contaminated soils and other areas of concern.
9.1 Radiologically Contaminated Soils
The following six remedial alternatives were considered for the radiologically contaminated soils:
Table 6 summarizes the comparative analysis.
Overall Protection
Overall protection of human health and the environment addresses whether or not an alternative provides adequate protection, and describes how risks are eliminated, reduced or controlled through treatment, engineering controls or institutional controls.
Alternative 1 relies on natural dispersion and decay processes to reduce levels of soil contamination. It does not meet the goals for remediating soil and is not effective in reducing risks to human health, if federal control of BNL is lost. In addition, contaminated soil would continue to be a source of groundwater contamination.
All other alternatives protect human health and the environment. For alternatives 2, 3, 5, and 6, long-term maintenance of the cap or cell and institutional controls are required for 100 years for it to remain protective of human health and the environment. Alternative 4 achieves protection of human health and the environment by removing contaminated soils above cleanup levels, with 50 years of institutional controls to reduce risk to acceptable levels.
Compliance with Applicable, or Relevant and Appropriate Requirements
These criteria consider if a remedy meets all applicable or relevant and appropriate requirements of federal and state environmental statutes, including provisions for invoking a waiver.
Alternatives 2 through 6 would meet the principal ARARs (i.e., the cleanup goals such as 15 mrem/yr above background levels for radionuclides as identified in Section 7, if control of the site is maintained by DOE). The NYSDEC guidance of 10 mrem/yr also was adopted as an As Low As Reasonably Achievable (ALARA) goal, which will be considered during the design and construction phase. Alternative 1 would not meet these remedial goals.
Alternative 2 is expected to meet these requirements for the 100-year period of institutional control. A potential remains for future exposure above federal and state requirements, because all soil, though capped, remains in the former Hazardous Waste Management Facility area and is otherwise untreated.
The alternatives for excavation and off-site disposal (Alternatives 3 and 4) and the alternative for soil washing (Alternative 5) involve removing a large fraction of the contaminated soil from the site and would lessen the chance of future exposures above federal and state requirements.
Cap or cell maintenance would be required for alternatives 2, 3, 5, and 6 to remain in compliance.
Alternatives in which soils are left on-site (Alternatives 1, 2, 3, 5, and 6) also would result in the creation of a radioactive waste disposal facility and would be subject to applicable state and federal regulations. State regulations do not allow the siting of a radioactive waste disposal facility on Long Island or over a sole-source groundwater recharge area.
Long-Term Effectiveness and Permanence
Long-term effectiveness and permanence relates to the amount of risk involved and addresses the ability of an alternative to protect human health and the environment over time, after the remediation goals have been met.
Alternative 1 is not effective in the long-term because all contaminated soils are left in place.
Alternative 2 is effective in meeting future-use federal and state requirements by preventing access to contaminated soils as long as institutional controls are maintained. However, the highest levels of contamination remain on-site and rely on the effectiveness and continued maintenance of an engineered barrier. Should that barrier fail or institutional control be lost, the long-term effectiveness of this alternative would be compromised.
Alternatives 3, 5, and 6 are more effective than alternative 2 in that the most contaminated soils are either removed from the site (Alternatives 3 and 5) or immobilized (Alternative 6). However, they also rely to some degree on the maintenance of an engineered barrier and continued institutional controls to assure long-term effectiveness.
Alternative 4 is considered the most effective and permanent alternative in the long-term since all contaminated soil above the soil remediation goals is removed and disposed of off-site.
Reduction of Toxicity, Mobility or Volume
Reduction of toxicity, mobility, or volume addresses the anticipated performance of treatment that permanently and significantly reduces toxicity, mobility, or volume of waste.
Alternative 1 provides no active reduction in on-site toxicity, mobility, or volume. There is a natural reduction in toxicity over time due to radioactive decay.
Alternative 2 provides no treatment of the contaminated soils and, hence, no reduction of toxicity and volume. Shielding of gamma radiation is provided by the cap, and the barrier provides a reduction in mobility.
Alternatives 3 and 5 provide a reduction of toxicity, mobility and volume through off-site disposal. In both alternatives, shielding of gamma radiation, as well as a reduction in radionuclide mobility, is provided by the cap. Soil washing provides an additional reduction in volume by treatment.
Alternative 4 provides a substantial reduction in toxicity, mobility, and volume through off-site disposal; however, no treatment is provided.
Vitrification in Alternative 6 provides the greatest reduction in the toxicity, mobility, and volume of the most contaminated soil through treatment into a glass monolith. The cap provides further shielding of the gamma radiation as well as a reduction in radionuclide mobility.
Short-Term Effectiveness and Environmental Impacts
Short-term effectiveness and environmental impacts addresses the effect to the community and site workers during construction and implementation of the remedy, and includes the time needed to finish work.
Risks to the community were evaluated for both radiological risk and transportation accidents associated with off-site disposal of contaminated soils. All alternatives are considered protective of the community in the short-term. There are no significant pathways of exposure to contaminated soils and dust from excavating and constructing the cap can be easily controlled. Alternatives 2, 3, 4, and 5 involve disposal of various volumes of contaminated soils off-site and do have some risks associated with railcar and traffic accidents. These risks can be controlled by federal (i.e., Department of Transportation) shipping requirements and are considered negligible. Alternatives 1 and 6 do not involve any off-site disposal and associated transportation risks.
Risks to remediation workers include both radiation risks and non-radiation construction accident risks. Alternative 1 provides the least risks to workers since there is no active remediation. Alternatives 2 and 5 are expected to provide the highest radiation exposures to remediation workers. Alternatives 3, 4, and 6 result in less exposures than Alternatives 2 and 5.
Implementability
Implementability addresses both the technical and administrative feasibility of an alternative, including the availability of materials and services required for cleanup.
Alternative 1 could be readily implemented with limited technical and administrative requirements.
Alternative 2 is technically feasible. However, it involves extensive excavation and complex administrative requirements for regulatory permits and approvals of an engineered disposal cell.
Alternatives 3 and 5 involve partially intrusive remediation activities. Alternative 3 is technically feasible and uses technologies that can be readily implemented with average administrative requirements, since only limited off-site shipment of waste is involved. Alternative 5 is less technically feasible, since the technology for soil washing has not been demonstrated on cesium-137 contaminated soils.
Alternative 4 involves excavating of large volumes of soils. It is technically feasible and could be readily implemented. Alternative 4 is expected to have above-average administrative requirements due to extensive procedures for documentation involved in the transport and off-site disposal of soil as low-level radioactive waste.
Alternative 6 is less intrusive, except for the consolidation activities. Vitrification has only limited full-scale use and may not be implementable. This alternative would have above- average administrative requirements. Overall, this alternative is considered very complex.
Cost
Cost compares the differences in cost, including capital, operation and maintenance. For estimated current costs of all alternatives, see Section 8.1.
9.2 Other Areas of Concern
This section summarizes the comparative analysis of the alternatives identified for the Ash Pit and the Upland Recharge/Meadow Marsh Area. Section 8.2 shows the costs. A comparative analysis was not conducted for the Recharge Basin HS, the Weaver Drive Recharge Basin HW, and the Wooded Wetland, as only one alternative was identified for these basins.
The following three remedial alternatives were considered for the Ash Pit:
For the Ash Pit, the no action alternative would not protect human health and the environment and did not comply with EPA’s soil guidance for lead. In addition the toxicity, mobility, and volume would not be reduced.
For the second alternative, a soil cap would protect workers, the public, and wildlife and meet EPA’s guidance. It is relatively simple to implement, would reduce the mobility of contaminants of concern, and is also cost-effective.
The third alternative, excavation and off-site disposal, would protect workers, the public, and wildlife. It is relatively simple to implement, would reduce the mobility of contaminants of concern, but is relatively costly for the limited benefits received.
The following three remedial alternatives were considered for the Upland Recharge/Meadow Marsh Area:
For the two man-made basins at the Upland Recharge/Meadow Marsh Area, the no action alternative would not protect breeding Tiger Salamanders. In addition, the toxicity, mobility, and volume of the contaminants of concern would not be reduced.
For the second alternative, Tiger Salamanders would be protected. It is technically feasible and would reduce the toxicity, mobility, and volume of contaminants in the ponds by removing and disposing the sediments off-site. However, this alternative involves complex administrative requirements for regulatory permits and approvals for on-site disposal.
The third alternative would also protect Tiger Salamanders. It is easy to implement and would reduce the toxicity, mobility and volume of contaminants in the ponds by disposing of the sediments off-site. This alternative is the most costly though it is only slightly more expensive than the second alternative and off-site disposal is readily available.
9.3 State and Community Acceptance
State Acceptance
State acceptance addresses whether the State agrees with, opposes, or has no comment on the preferred alternative. The State of New York concurs with the selection of remedial actions described in this Record of Decision.
Community Acceptance
Community acceptance addresses the issues and concerns that the public may have on each of the alternatives. Information sessions were held on April 13 and 14, 1999, and a public meeting was held on April 22, 1999 about the proposed plan and feasibility study supporting this Record of Decision. The results of the public meeting and the public comments on the feasibility study and proposed plan indicate overall general acceptance and support of the preferred alternatives. Community response to the remedial alternatives is presented in the Responsiveness Summary in Section III, which addresses questions and comments received during the public comment period.
10. SELECTED REMEDIES
Remedies have been selected based on consideration of CERCLA requirements, the analysis of alternatives and public comments. The selected remedies are believed to provide the best balance of tradeoffs among the alternatives with respect to the nine CERCLA evaluation criteria used to evaluate the remedies (Section 9).
In addition to the remedies discussed below, institutional controls will be maintained to ensure that uses are protective of public health and the environment and that the remedy is not negatively impacted. Examples include land use restrictions (i.e. some areas are not suitable for residential use) and controlling the types of activities that can be performed at certain areas such as limiting construction on the top of capped landfills. In addition, any sale or transfer of BNL properties will also meet the requirements of 120(h) of CERCLA to ensure that future users are not exposed to unacceptable levels of contamination. For example, deed restrictions may be used to limit uses of a particular site and to prevent the installation of drinking water wells into contaminated groundwater.
The selected remedies address three distinct components: radiologically contaminated soils; other Areas of Concern; and removal actions adopted as final actions. The following is a description of the selected remedial actions, which is also summarized in Table 7. Table 8 summarizes the costs.
10.1 Radiologically Contaminated Soils
The selected remedy for radiologically contaminated soils is Alternative 4 and involves excavation and off-site disposal of soils above cleanup goals, institutional controls and long-term monitoring. The major components of this remedy are:
10.2 Other Areas of Concern
Remedies for the other Areas of Concern are described below:
10.3 Removal Actions
In addition, several removal actions that either have been completed or are ongoing are being selected as final remedies. Each was selected in an Action Memorandum and subject to public participation.
Groundwater contamination associated with the Former Landfill Area (AOC 2) and off-site groundwater contamination associated with other Operable Unit I AOCs will be addressed in the Operable Unit III Record of Decision. An evaluation of remedial alternatives for deep contaminated soil associated with the Brookhaven Linear Accelerator Isotope Producer (BLIP) facility (AOC 16K) is underway. The final remedy for this AOC will be documented in a subsequent Record of Decision.
11. STATUTORY DETERMINATIONS
Selection of a remedy is based on CERCLA, and its amendments, and the regulations in the National Contingency Plan. All remedies must meet the threshold criteria, protect human health and the environment, and comply with ARARs. CERCLA also requires that the remedy uses permanent solutions and alternative technologies for treatment to the maximum extent practicable, and that the implemented action is cost-effective. Finally, the statute includes a preference for remedies that employs treatment that permanently and significantly reduces the volume, toxicity, or mobility of hazardous wastes as their principal element. The following sections discuss how the selected remedy meets these statutory requirements.
11.1 Protection of Human Health and the Environment
The selected remedy for the radioactively contaminated soils protects human health and the environment by removing and disposing of contaminated soils and associated structures and by implementing monitoring and institutional controls to prevent exposure to contaminants that pose a risk. Removing these wastes minimizes both risks of expose to on-site workers and risks associated with future-use scenarios, as well as minimizing the potential for migration of contaminants into the underlying groundwater.
Reconstructing and monitoring the Upland Recharge/Meadow Marsh Area and the routine maintenance and monitoring of Recharge Basin HS and the Weaver Drive Recharge Basin HW will minimize potential risks to the Tiger Salamander and other ecological receptors. A Tiger Salamander Habitat Management Plan will be developed to minimize the impacts to the Tiger Salamander from continued operation of the Recharge Basin HS and the Weaver Drive Recharge Basin HW under NYSDEC permits.
The soil cover that will be placed at the Ash Pit eliminates the potential for direct exposure to the ash.
The covers placed at the Current Landfill, Former Landfill, Interim Landfill, and Slit Trench eliminate the potential for direct exposure to the landfill’s contents, control landfill gases, and minimize the infiltration of precipitation and migration of contaminants to subsurface soils, surface water, and groundwater. The excavation of buried wastes and contaminated soils at the Chemical/Animal Pits and Glass Holes has removed the potential for further contamination of underlying soils and groundwater.
Potential future risks to human health and the environment due to contaminated groundwater will be eliminated through extraction and treatment. For contamination presently on-site, the groundwater cleanup goals will be met by extracting groundwater contaminated with VOCs from the Current Landfill/former HWMF plume.
No unacceptable short-term risks or cross-media impacts will be caused by implementating these remedies.
11.2 Compliance with ARARs
The National Contingency Plan, Section 300.430 (P) (5) (ii) (B) requires that the selected remedy attains the federal and state ARARs, or obtains a waiver of an ARAR.
The chemical-specific ARARs that the selected remedies will meet are listed below.
1. Safe Drinking Water Act, Public Law 95-523, as amended by Public Law 96502, 22 USC 300 et. seq. National Primary Drinking Water Regulations (40 Code of Federal Regulations 141) and National Secondary Drinking Water Regulations (40 Code of Federal Regulations 143). This establishes MCLs and secondary MCLs for public drinking water supplies that are relevant and appropriate for establishing goals for remediating groundwater.
2. New York Water Quality Standards, 6 NYCRR Part 703. This requirement establishes standards of quality and purity for groundwaters of the State and effluent guidelines.
3. 6 NYCRR Part 212, General Process Emission Sources. This state regulation will be used to establish the need for air-emission control equipment for the air stripper associated with the groundwater extraction system.
4. RCRA (40 Code of Federal Regulations parts 260-268), this defines hazardous wastes. All wastes classified as hazardous will be handled, stored, and disposed of in accordance with these regulations. Hazardous wastes will be disposed of off-site at a permitted facility.
5. New York State Hazardous Waste Regulations (6 NYCRR Part 370 - 373). This defines hazardous wastes in New York State. All wastes classified as hazardous will be handled, stored, and disposed of in accordance with these regulations. Hazardous wastes will be disposed of off-site at a permitted facility.
6. 10 NYCRR Part 5, New York State Department of Health Drinking Water Standards.
No location-specific ARARs were identified.
1. 10 Code of Federal Regulations Part 835. This regulation establishes the requirements for controlling and managing radiologically contaminated areas.
2. 6 NYCRR Part 360, Solid Waste Management Facilities. The landfills were and will be capped in accordance with these requirements. Solid wastes will be handled in accordance with these requirements.
3. RCRA (40 Code of Federal Regulations parts 260-268). As described above.
4. New York State Hazardous Waste Regulations (6 NYCRR Part 370 - 373). As described above.
5. Clear Air Act (42 U.S.C Section 7401, et seq.) and National Emissions Standards for Hazardous Air Pollutants (40 Code of Federal Regulations Part 61). These regulate and limit emissions of hazardous air pollutants, including radionuclides.
In implementing the selected remedy, the following significant guidance will be considered. Those which are not promulgated are not legally binding.
1. NYSDEC Technical and Administrative Guidance Memorandum "Remediation Guideline for Soils Contaminated with Radioactive Materials" (#4003), September, 1993. This memorandum contains State guidance for remediating radiologically contaminated soils. The State’s value of 10 mrem/yr above background serves as an additional goal for remediation to be evaluated during remedial design and implementation.
2. NYSDEC Division of Air Guidelines for Control of Toxic Ambient Air Contaminants, Air Guide 1. This guide will be used to evaluate the impacts of air emissions from the air-stripping portions of the selected remedy, and to assist with evaluating the need for air-emissions control equipment.
3. NYSDEC Technical and Administrative Guidance Memorandum: Determination of Soil Remediation Objectives and Remediation Levels (# 4046), January 1994. The recommended soil remediation objectives for Volatile Organic Compounds, chromium and cadmium were selected as remediation goals to guide excavations at the Chemical/Animal Pits and Glass Holes.
4. U. S. EPA Revised Interim Soil Lead Guidance for CERCLA Sites and RCRA Corrective Action Facilities, OSWER Directive No. 9355.4-12, PB94-963282, August 1994. Guidance for remediating soil for lead at the Ash Pit.
5. U.S. EPA Soil Screening Guidance: User’s Guide, EPA/540/R-96/018, April, 1996. Goals for remediating soil for lead and mercury were developed using this guidance. These goals were used to guide excavations at the Chemical/Animal Pits and Glass Holes.
6. DOE Order 5400.5 and Draft 10 Code of Federal Regulations 834 "Radiation Protection of the Public and the Environment". This order, and its current draft rule-making, were used to develop radiological soil remediation levels. The basic public dose limit for exposure to residual radioactive material for DOE facilities such as BNL, is 100 mrem/yr above background plus application of the As Low As Reasonably Achievable (ALARA) policy. Based on BNL site-specific conditions and ALARA, 15 mrem/yr above background was selected. This level is consistent with risk requirements under CERCLA and EPA guidance.
7. NYSDEC Technical and Administrative Guidance Memorandum: Accelerated Remedial Actions at Class 2, Non-RCRA Regulated Landfills. HWR-92-4044, March 9, 1992. This memorandum defines the Chemical/Animal Pits and Glass Holes as "hot spots", which contain concentrated wastes and meet criteria to consider source removal as an option.
8. U.S. EPA Presumptive Remedy for CERCLA Municipal Landfill Site (Office of Solid Waste and Emergency Response. Directive No. 93555.0-49 Feasibility Study, EPA 540-F-93-035 September, 1993). Capping of the landfills was an appropriate remedy. This directive considers wastes found in the Chemical/Animal Pits and Glass Holes as not appropriate for capping.
9. U.S. EPA Establishment of Cleanup Levels for CERCLA Sites with Radioactive Contamination. OSWER Directive 9200.4-18, August, 1997. This directive recommends an allowable exposure to radionuclides to 15mrem/yr above natural background as consistent with EPA’s acceptable risk range.
11.3 Cost-Effectiveness
Based on the expected performance standards, the selected remedies were determined to be cost-effective because they provide overall protection of human health and the environment, long- and short-term effectiveness, and compliance with ARARs, at an acceptable cost. Table 8 summarizes the total costs for Operable Unit I.
11.4 Use of Permanent Solutions and Alternative Treatment Technologies to the Maximum Extent Practicable
The selected remedies represent the maximum extent to which permanent solutions and treatment technologies can be used cost-effectively. The selected remedies provide the best balance of tradeoffs in terms of long-term effectiveness and permanence; reduction in toxicity, mobility, or volume achieved through treatment; short-term effectiveness; implementability; and cost. The statutory preference for treatment as a principal element as well as State and community acceptance also was considered.
Large-scale excavation and off-site disposal of radiologically contaminated soils is a permanent solution that removes contamination from the areas of concern. Treatment technologies for radiologically contaminated soils were evaluated but not selected due to limited effectiveness and the poor ability to implement.
Permanent solutions also were selected for the other areas of concern to the extent practicable, considering the best balance in trade-offs. Removing sediments and reconstructing the wetlands at the Upland Rechanrge/Meadow Marsh Area represents a permanent solution that will protect the Tiger Salamander. The Tiger Salamander will also be protected at the Recharge Basin HS and the Weaver Drive Recharge Basin HW with the development of a Tiger Salamander Habitat Management Plan. Soil cover of the Ash Pit eliminates direct exposure.
The remedies previously implemented of capping the Current Landfill, Former Landfill, Slit Trench, and Interim Landfill, and bulk excavation and off-site disposal of the Chemical/Animal Pits and Glass Holes, are solutions for source control and minimizing the migration of contaminants. Groundwater solutions include treating Volatile Organic Coumpounds at the BNL southern boundary, monitoring, and institutional controls. Groundwater treatment for Volatile Organic Compounds represents a permanent solution and implementation of treatment technology.
11.5 Preference for Treatment as a Principal Element
Treatment of radiologically contaminated soils was not found to be practical since there are no techniques to reduce radioactivity. Techniques which minimize waste volumes or further stabilize wastes to meet disposal facility requirements may be identified during remedial design.
The components of the selected remedy for groundwater are final actions and satisfy the statutory preference for treatment as a principal element. Groundwater contaminated with total Volatile Organic Compounds is being extracted and treated by air-stripping before recharge back to the aquifer.
11.6 Documentation of Significant Changes
Comments received during the public comment period for the proposed plan and feasibility study that support this Record of Decision were reviewed. No significant changes to the selected remedy, as originally identified in the proposed plan, were necessary.
11.7 Five-Year Review
Five-year reviews will be needed to evaluate the effectiveness of the institutional control period to achieve total reduction in risk at the radiological contaminated waste sites, to evaluate the activities taken to protect the Tiger Salamander, and to evaluate the effectiveness of landfill caps and the groundwater treatment system.
REFERENCES
BNL, 1994. Action Memorandum Landfill Closure Removal Action Phase I - Current Landfill. December, 1994.
BNL, 1995. Future Land Use Plan. August, 1995.
BNL, 1996a. Action Memorandum Landfill Closure Removal Action Former Landfill Area. April 8, 1996.
BNL, 1996b. Action Memorandum Operable Unit I Groundwater Removal Action and Operable Units & III Public Water Hookups. December, 1996.
BNL, 1997. Final Action Memorandum Phase III - Landfill Closure Removal Action. June 16, 1997.
BNL, 1999. Proposed Plan for Operable Unit I and Radiologically Contaminated Soils. April 1999.
CDM, 1994. Final Remedial Investigation/Risk Assessment Report, Operable Unit IV. December 1994.
CDM, 1995a. Final Engineering Evaluation/Cost Analysis for Landfill Closure Action, Operable Unit I. March 1995.
CDM, 1995b. Final Engineering Evaluation/Cost Analysis for Groundwater, Operable Unit I. September 1995.
CDM, 1996a. Final Remedial Investigation/Risk Assessment Report, Operable Unit I/VI. June 14, 1996.
CDM, 1996b. Final Construction Certification Report for Current Landfill Capping. May 1996.
CDM, 1997. Chemical/Animal Pits and Glass Holes, Final Evaluation of Alternatives Report. April 1997.
CDM, 1999a. Final Feasibility Study Report Operable Unit I Radiologically Contaminated Soils. February 26, 1999.
CDM, 1999b. Final Focused Ecological Risk Assessment Operable Units I/VI. Appendix L, Final Feasibility Study Report Operable Unit I Radiologically Contaminated Soils. March 31, 1999.
CDM, 1999c. Addendum, Focused Ecological Risk Assessment Operable Units I/VI. June 9, 1999.
EPA, 1989. Risk Assessment Guidance for Superfund; Human Health Evaluation Manual Part A. U.S. Environmental Protection Agency, Office of Solid Waste and Emergency and Remedial Response, OSWER Directive 9285.701A.
EPA, 1994. Guidance on Residential Lead-Based Paint, Lead Contaminated Dust, and Lead Contaminated Soil. U.S. Environmental Protection Agency. July 1994.
EPA, 1996. Soil Screening Guidance: User’s Guide. U.S. Environmental Protection Agency, Office of Solid Waste and Remedial Response. OSWER Directive 9355.4-23, 1996.
EPA, 1997. Establishment of Cleanup Levels for CERCLA Sites with Radioactive Contamination U.S. Environmental Protection Agency, Office of Solid Waste and Remedial Response.. OSWER Directive 9200.4-18, August 1997.
IT, 1999. Final Operable Unit II/VII Remedial Investigation Report. February 1999.
J. Meersman, BNL to J. Lister, NYSDEC, 1999. Operable Unit II/VII Supplemental Surface Sampling - Preliminary Metals Results. June 1, 1999.
J. Meersman, BNL to J. Lister, NYSDEC, 1999. Operable Unit II/VII Supplemental Surface Sampling - Preliminary Radiological Results. May 18, 1999.
NYSDEC, 1994. Technical and Administrative Guidance Memorandum: Determination of Soil Remediation Objectives and Remediation Levels. HWR-94-4046, New York State Department of Environmental Conservation, Division of Hazardous Waste Remediation. January 24, 1994 (revised).
P.W. Grosser, 1997. Interim Landfill Closure Report. November, 1997.
SAIC, 1992. Brookhaven National Laboratory Response Strategy Document. 1992.
Weston, 1997. Former Landfill Closure Construction Certification Report. March 1997.
1. INTRODUCTION
This Responsiveness Summary of the Record of Decision presents the public comments and concerns and the U.S. Department of Energy’s (DOE) responses to those comments and concerns that address the Feasibility Study Report (FS) and the Proposed Plan for Operable Unit I (OU I) and several areas of radiologically contaminated soils at Brookhaven National Laboratory (BNL).
The Responsive Summary serves the following two functions:
A public comment period for the review of the OU I Proposed Plan and the OU I Feasibility Study began on April 1, 1999 and ended on April 30, 1999. A public meeting was held on April 22, 1999 at 7:30 p.m. in the Berkner Hall Auditorium at Brookhaven National Laboratory. Approximately 40 people attended this meeting. Copies of the Proposed Plan and other related infomational material were available. Copies of the OU I Proposed Plan and the Feasibility Study were provided at the following Administrative Record/Information Respositories for public review:
Based on the comments received during the public meeting and comment period, the DOE believes that the EPA, NYSDEC, BNL, local government officials and residents were responsive to the Proposed Plan and generally support DOE’s preferred remedial alternatives. No major objections to the preferred remedy were raised at the public meeting or during the comment period. Section 4 of this Responsiveness Summary summarizes responses to all comments pertaining to the Proposed Plan and Feasibility Study.
The Responsiveness Summary is divided into the following sections:
2. OVERVIEW OF THE RESPONSIVENESS SUMMARY
This section briefly describes the site background and DOE’s proposed alternatives.
3. BACKGROUND ON COMMUNITY INVOLVEMENT AND CONCERNS
This section provides the history of community concerns and describes community involvement in selecting a remedy for OU I.
4. COMPREHENSIVE SUMMARY OF MAJOR QUESTIONS, COMMENTS AND CONCERNS, AND DOE RESPONSES
This section summarizes the written comments DOE received during the public comment period, the oral and written comments received during the public meeting, and DOE’s responses.
5. RESPONSES TO DETAILED COMMENT LETTERS
This section contains specific written responses to the significant comment letters. Comments from these letters also are given in the summaries in Section 4 of this document.
6. CHRONOLOGY OF COMMUNITY RELATIONS ACTIVITIES
This section gives a chronology of the significant Community Relations activities that pertain to OU I.
2. OVERVIEW OF THE RESPONSIVENESS SUMMARY
2.1 Site History
The BNL site, formerly Camp Upton, was occupied by the U.S. Army during World Wars I and II. Between the wars, the site was operated by the Civilian Conservation Corps. It was transferred to the Atomic Energy Commission in 1947, to the Energy Research and Development Administration in 1975, and to DOE in 1977.
In 1980, the BNL site was placed on NYSDEC’s list of Inactive Hazardous Waste Sites. On December 21, 1989, the BNL site was included on EPA’s National Priorities List because of contamination of soil and groundwater that resulted from past operations of the facility. Subsequently, the EPA, NYSDEC, and DOE entered into a Federal Facilities Agreement (herein referred to as the IAG) that became effective in May 1992 (Administrative Docket Number: II-CERCLA-FFA-00201) to coordinate cleanup activities. The IAG identified areas of concern that were grouped into Operable Units to be evaluated for response actions. The IAG requires a Remedial Investigation/Feasibility Study for OU I, pursuant to 42 U.S.C. 9601 et. seq., to meet CERCLA requirements. The IAG also requires cleanup actions to address the identified concerns. Cleanup at the BNL site will be conducted pursuant to CERCLA, 40 CFR Part 300.
BNL’s Response Strategy Document (SAIC, 1992) grouped the identified areas of concern into seven Operable Units. OU II and VII were subsequently combined. Remedial investigations and risk assessments (CDM Federal 1996a, IT 1999a) were conducted. In addition, several accelerated cleanup actions were taken as discussed in Section II and an interim action was taken at the Building 650 Sump Outfall Area. The Sump Outfall Area was fenced off to prevent unnecessary access. Risk assessments were conducted to evaluate the nature and extent of contamination, and potential risks associated with the areas of concern are addressed in this Record of Decision. A Feasibility Study (CDM Federal 1999a) was prepared to evaluate the alternatives for remediating the radiologically contaminated soils and other areas of concern addressed in this Record of Decision.
2.2 Site Description
An overview of the areas of concern addressed in this Record of Decision is presented below.
2.3 Radiologically Contaminated Soils
Radiologically contaminated soils from the following areas of concern are included in this Record of Decision.
The OU I and Radiologically Contaminated Soils Feasibility Study evaluated several remedial alternatives to address soil and sediment contamination. The Proposed Plan recommended that radiologically contaminated soil above cleanup goals be excavated, disposed of off-site and institutional controls be implemented. Some associated structures also will be removed.
All wastes will be transported off-site to a permitted disposal facility.
2.4 Other Areas of Concern
There are other areas of concern which have low concentrations of metals as the primary contaminant of concern.
Upland Recharge/Meadow Marsh Area
The Upland Recharge/Meadow Marsh Area (AOC 8) was the site of an experiment for evaluating the capacity of small natural and artificial terrestrial and aquatic ecosystems for sewage treatment and recharge of ground and surface waters.
The Remedial Investigation found no human health risks from exposures to soils or sediments. However, the focused Ecological Risk Assessment identified the potential for ecological risk to tiger salamanders by exposure to metals. Groundwater contaminated with ethylene dibromide and contaminated soils is addressed in a separate Record of Decision for OU VI.
The recommended remedy for two ponds in the Upland Recharge/Meadow Marsh Area is excavating of contaminated sediments and disposing of the wastes off-site. The two wetlands will be reconstructed.
Recharge Basins
Recharge Basins HS (AOC 24E) and Weaver Drive Basin HW (AOC 24F) receive storm water effluent, and are included in the BNL State Pollution Discharge Elimination System (SPDES). The recommended remedy is operational maintenance and monitoring for the recharge basins. A Tiger Salamander Habitat Management Plan is being prepared in conjunction with the NYSDEC to protect this species from routine basin maintenance.
Ash Pit
The Ash Pit was used disposing of ash and slag from a solid waste incinerator that operated from 1943 to 1963. The proposed remedy is to cover the Ash pit with a soil cap and provide institutional controls and maintenance to prevent exposures.
Wooded Wetland
The Wooded Wetland received runoff from the Current Landfill when it was operating. The proposed remedy is institutional control and monitoring.
2.5 Removal Actions
DOE determined that accelerated cleanup actions, called removal actions, were required for several areas of concern. The potential removal actions were evaluated in Engineering Evaluation/Cost Analysis Reports that were prepared pursuant to CERCLA (CDM Federal, 1995a; CDM Federal, 1995b; and CDM Federal, 1997a). These reports were made available for public review and were approved by the regulatory agencies. The removal actions selected, after considering public comments, are documented in Action Memorandum (BNL, 1994; BNL, 1996; BNL, 1997).
Several landfill areas of concern were capped to prevent contaminates from migrating. Geomembrane caps, constructed pursuant to 6 NYCCR Part 360, were placed over the Current Landfill, Former Landfill, Slit Trench, and Interim Landfill. Its construction was completed in November, 1995 at the Current Landfill, in October 1996 at the Former Landfill and Slit Trench, and in November 1997 at the Interim Landfill. Details are documented in construction certification reports (CDM Federal, 1996b; Weston, 1997; and P.W. Grosser, 1997). The National Weather Service stockpile was used as fill for the Former Landfill cap. A 55-gallon drum containing soil with levels of radionuclides too high to place under the cap is stored at the former HWMF and will be disposed of off-site.
Contaminant soil, debris, and intact bottles were excavated and segregated for treatment and/or disposal from the Chemical/Animals Pits and Glass Holes. Samples were taken at each pit to ensure that cleanup levels of soil were met.
Several actions are being taken to address contamination of groundwater resulting from waste disposal at the former HWMF and the Current Landfill. A groundwater pump and treat system was installed in December 1996 at the BNL southern boundary to extract and treat Volatile Organic Compounds (VOC) that contaminate groundwater downdgradient of OU I source areas. The system is designed to remove these chemicals by air stripping. The groundwater is recharged upgradient using a recharge basin. Groundwater from the area is being monitored. Contamination of groundwater associated with the Former Landfill and contaminated groundwater that has migrated off-site will be addressed in the OU III Record of Decision.
These removal actions are being adopted as final actions in this Record of Decision.
2.6 Level of Community Support for the Proposed Alternatives
Based on comments received during the public comment period, DOE and BNL believe that the public and local elected officials are in general agreement with the above recommended remedial alternatives. One-third of the comments received endorsed the proposed alternatives. There was one comment indicating a preference for using vitrification or soil washing. The remaining comments did not express an opinion for or against the proposed alternatives. The principal issues of concern were control of dust during excavation, the potential for transportation accidents, and deer contaminated with cesium-137.
2.7 Changes in the Proposed Plan
No changes to recommended remedies given in the Proposed Plan are required based on public or local official comments, or based on the EPA’s and the NYSDEC’s recommendations.
3. BACKGROUND ON COMMUNITY INVOLVEMENT AND CONCERNS
3.1 Community Profile
BNL is located in Brookhaven Town at the geographic center of Suffolk County, which encompasses the central and eastern part of Long Island. With a population of approximately 430,000, Brookhaven Town accounts for about 16 percent of Long Island's 2.6 million residents. Suffolk County is operated by a county executive and an 18-member legislature. Brookhaven Town employs a town council (six at-large councilors) and a supervisor. Both governments maintain professional planning, development and environment departments, plus planning boards.
Many villages and hamlets dot Brookhaven Town's 260 square miles, and BNL is surrounded by the unincorporated communities of East Yaphank, Yaphank, Ridge, Middle Island, and Manorville. Most of these villages and hamlets have citizen-run civic or taxpayer organizations with large and active memberships. Most organizations join one or both of the area's two umbrella civic groups, the Affiliated Brookhaven Civic Organization and the Longwood Alliance. These communities support service clubs, which represent the businesses, churches, and other aligned interests within the community.
The town of Riverhead is another Suffolk County town where BNL activities generate interest. It is to the east of BNL beyond the Town of Brookhaven, has a population of about 24,500, and an area of about 60 square miles of which 41 percent is farmed. Riverhead employs a supervisor-town council government, which maintains professional planning, development and environment departments, plus a planning board.
3.2 History of Community Involvement
Historically, public involvement in BNL's environmental restoration activiti
