United Stales Office of Environmental Protection Emergency and Agency Remedial Response EPA/ROD/R05-92/212 September 1992 c/EPA Superfund Record of Decision: Skinner Landfill, OH ------- NOTICE. The appendices listed in the index that are not found in this document have been removed at the request 01 the issuing agency. They contain material which supplement. but adds no further applicable information to the content of the document. All supplemental material is, however, contained in the administrative record for this site. ------- 50272.101 REPORT DOCUMENTATION 11. REPORTNO. PAGE EPA/ROD/ROS-92/212 I ~ 3. Recipienta Acc:eaalon No. v 4. 1118 8nd Sub1IUe SUPERFUND RECORD OF DECISION Skinner Landfill, OH First Remedial Action - Interim 7. Author(a) 5. Aepor1 Date 09/30/92 6. 8. Perfonning Organization Rept. No. 8. Perfonnlng OrgalnlDtion Name and Addresa 10. ProjectlT88klWork Unit No. 11. ConIr8c1(C) or Gr8nt(G) No. (C) (G) 12. Sponaorlng Organization Name 8nd Address U.S. Environmental Protection 401 M Street, S.W. Washington, D.C. 20460 . 13. Type 01 Report & Period Covered Agen(;:y 800/000 14. 15. Supplementary Notes PB93-964117 16. Ab8tract (Umlt: 200 wolda) The 78-acre Skinner Landfill site is located in West Chester, Butler County, Ohio. Land use in the immediate vicinity includes business and residential uses to the west and crop farming to the north. Several geologic units that underlie the site are used as aquifers by local residents. The site was used in the past for the mining of sand and gravel, and was operated for the landfilling of a wide variety of materials from approximately 1934 through 1990. Materials deposited onsite include demolition debris, household refuse, and a wide variety of chemical wastes. A low area of the site, referred to as the waste lagoon, was used for disposal of paint and ink wastes, creosote, pesticides, and other chemicals. In 1976, in response to a fire onsite and reports of observations of a black, oily liquid in a waste lagoon onsite, EPA investigated the landfill. The owner asserted that nerve gas, mustard gas, incendiary bombs, and other explosive devices were buried at the landfill in the lagoon area, but subsequently retracted this claim. The U.S. Army and EPA dug several trenches into the buried waste lagoon and found black ooze and numerous barrels of waste; no munitions of any sort were found. In 1982, EPA conducted an investigation that showed that the groundwater southeast of the buried waste lagoon was contaminated with VOCs. RI (See Attached Page) 17. Document Analyaia L Deacrlptora Record of Decision - Skinner Landfill, OH First Remedial Action - Interim Contaminated Media: Soil, sediment, gw Key Contaminants: VOCs (benzene), other (arsenic) organics (PAHs, PCBs, pesticides), metals b. IdentifieralOpen-Ended Terms c. COSA 11 FI8IcIIGroup 18. Avllliabiity Statement 19. Security Clua (Thia Report) None 20. Security Clua (Thia Page) Nnnp 21. No. 01 Pages 16 ~ ~ Price (See ANSJ.Z39.18) See Inslrllc/ions on Reverse 272 (4-77) (Formerly NTlS-35) Department 01 Conmerce ------- EPA/ROD/R05-92/212 Skinner Landfill, OH First Remedial Action - Interim Abstract (Continued) studies conducted between 1986 and 1989 investigated the site ground water, surface water, soil, and sediment. In 1990, the state closed the site to further landfilling activities. EPA has organized this project into two operable units. This ROD is an interim action to protect human health by limiting site access to prevent ingestion of and direct contact with contaminated soil, and to protect the potentially affected users of ground water on and near the site. A future ROD will provide source control measures and the remaining onsite contaminants as the final response action for this site. The primary contaminants of concern affecting the soil and ground water are VOCs, including benzene; organics, including PAHs, PCBs, and pesticides; and metals, including arsenic. The selected interim remedial action for this site includes fencing the portion of the site that was used for landfilling and disposal of liquid wastes; posting warning signs; monitoring ground water for organic and inorganic contaminantson a quarterly basis; and providing an alternative water supply to those who are potentially impacted by migration of contaminated ground water from the site. The estimated present worth cost for this remedial action is not provided. The capital cost is $160,000 and the annual O&M cost is $30,000. PERFORMANCE STANDARDS OR GOALS: No performance clean-up goals were provided for remedial action. The subsequent ROD will address the clean-up goals for the chemicals of concern contaminating the soil, sediment, ground water, and surface water. ------- DECLARATION FOR THE RECORD OF DECISION SITE NAME AND LOCATION Skinner Landfill West Chester, Butler County, Union Township, Ohio STATEMENT OF BASIS AND PURPOSE This decision document presents the selected interim remedial action for the Skinner Landfill site in ~est Chester, Ohio, which was chosen in accordance with the requirements of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), as amended by the Superfund Amendments and Reauthorization Act of 1986 (SARA) and to the extent practicable, the National oil and Hazardous Substances Pollution Contingency Plan (NCP). This decision document explains the factual and legal basis for selecting the interim remedy for this site. The information supporting this interim remedial action decision is contained in the administrative record for this site. The state of Ohio concurs with the selected remedy. ASSESSMENT OF THE SITE Threatened releases of hazardous substances from this site, if not addressed by implementing the respo~se action selected in this ROD, may present an imminent and substantial endangerment to public health, welfare, or the environment. DESCRIPTION OF THE SELECTED REMEDY This interim action operable unit is the first of two operable units for this site. This operable unit addresses potential contamination of drinking water by eliminating the risks, by providing alternative water supply to those potentially affected users of groundwater, and by monitoring the groundwater at the downgradient boundary of the site. It also provides for the fencing of the contaminated portions of the site. The second operable unit will provide for control of the on-site contamination, and is intended to be the final response action for this site. ------- DECLARATXON This interim action is protective of human health, complies with Federal and state applicable or relevant and appropriate requirements for this limited-scope action, and is cost- effective. Further protection of human health, and protection of the environment, will be addressed in future operable units. This action is interim and is not intended to utilize permanent solutions and alternative treatment (or resource recovery) technologies to the maximum extent practicable for this site. Because this action does not constitute the final remedy for this site, the statutory preference for remedies that employ treatment that reduces toxicity, mobility, or volume as a principal element will be addressed by the final response action. Subsequent actions are planned to address fully the threats posed by the conditions at this site. Because this remedy will result in hazardous substances remaining on site above health-based levels, a review will be conducted to ensure that the remedy continues to provide adequate protection of human health and the environment within five years after commencement of the remedial action. Because this is an interim action ROD, review of this site and of this remedy will be ongoing as U.S. EPA continues to develop final remedial alternatives for this site. ¥~ ~ /r112. Date Valdas V. Ad us Regional Ad nistrator U.S. EPA, R gion V ------- o Decision Summary SITE NAME. LOCATION. AND DESCRIPTION.- The Skinner Landfill site is located in West Chester, Ohio, in Section 22 of Butler County (see Figure 1). The Skinner site is comprised of approximately 78 acres of hilly terrain, bordered to the south by the East Fork of Mill Creek, on the east by Conrail railroad tracks. Land uses in the immediate site vicinity include business and residential uses to the west and crop farming to the north. Cincinnati-Dayton Road borders the site to the west. An elementary school is located immediately across Cincinnati-Dayton road from the site. The site was used in the past for the mining of sand and gravel, and was operated for the landfilling of a wide variety of materials from approximately 1934 through 1990. Materials deposited on the site include demolition debris, household refuse, and a wide variety of chemical wastes. A low area in the center of the site, referred to as the waste lagoon, was used for the disposal of paint wastes, ink wastes, creosote, pesticides, and other chemical wastes. Several geologic units which underlie the site are used locally as aquifers. SITE HISTORY AND ENFORCEMENT ACTIVITIES In 1976, in response to a fire on the site and reports of observations of a black, oily liquid in a waste lagoon on the site, the Ohio EPA began an investigation of the Skinner Landfill. During the course of this investigation, the Skinners covered the waste lagoon with a layer of demolition debris, thereby hindering the investigation. Albert Skinner, the site owner at the time, dissuaded the Ohio EPA from accessing the lagoon area by claiming that nerve gas, mustard gas, incendiary bombs, phosphorus, flame throwers, cyanide ash, and other explosive devices were buried at the landfill. This prompted the Ohio EPA to request the assistance of the U.S. Army. Albert Skinner, in the presence of Ohio EPA attorneys and the U.S. Army investigators, subsequently retracted his claims of the presence of ordnance. The U.S. Army and Ohio EPA then dug several trenches into the buried waste lagoon, and found black ooze and a number of barrels of wastes. Subsequently, records searches have been performed by the U.S. Army, and have indicated that there is no record of any munitions of any sort being disposed of at the Skinner Landfill site. In 1982, the U.S. EPA conducted a limited investigation of the site for the purpose of scoring the Skinner Landfill site for inclusion on the'National Priorities List (NPL). This ------- 2 investigation showed that the groundwater southeast of the buried waste lagoon was contaminated with vo1atile organic compounds. The Skinner Landfill site was then placed on the NPL. In 1986, the U.S. EPA began a Phase I Remedial Investigation, with the sampling of ground water, surface water, and soils. biological survey of the East Fork of Mill Creek and Skinner Creek was also performed. A In 1989, the U.S. EPA began its Phase II Remedial Investigation ("Phase II RI"), to further investigate the site groundwater, surface water, soils, and-sediments. Overall, over 400 samples from the site were analyzed in chemical laboratories. The Remedial Investigation resulted in the installation of 33 soil borings, and 39 groundwater monitoring wells. In August 1990, through a legal proceeding, the Ohio EPA closed the site to all further landfilling activities. COMMUNITY PARTICIPATION During the course of the investigation, a number of meetings were held with the community and with a local activist group. A fact sheet outlining U.S. EPA's plans for the investigation of the Skinner Landfill site was distributed to the public in March of 1986. A fact sheet describing the res'llts of Phase I of the Remedial Investigation (RI) and plans for hlase II of the RI was distributed to the public in April of 1987. A fact sheet describing the results of Phase II of the RI and plans for the Baseline Risk Assessment (RA) and Feasibility Study (FS) was distributed to the public in June of 1991. Representatives of the U.S. EPA and the Ohio EPA held a public meeting in West Chester, Ohio on June 20, 1991 to discuss the results of the Phase II RI and plans for future activities at the Skinner site. A fact sheet describing the results of the Feasibility study, and presenting the U.s. EPA's preferred alternative for a comprehensive cleanup of the entire Skinner Landfill site was distributed to the public in April, 1992. A component of this cleanup plan was on-site incineration of approximately 17,000 cubic yards of lagoon wastes. A public meeting to discuss the proposed plan and to gather pUblic comments was held on May 20, 1992. A second public meeting on this subject was held on July 29, 1992. An ancillary purpose of this second public meeting was to present to the pUblic the results of an assessment of the risks posed by the on-site incineration option, which had been ------- 3 requested at the May 20, 1992 public meeting. However, this meeting was disrupted by a local activist group to the point that the risk assessment information was not adequately conveyed to the public. Subsequent to the second public meeting, and due to concerns expressed by members of the public and by elected officials, the U.S. EPA decided to alter its decisionmaking approach for this site. On August 7, 1992, U.S. EPA mailed an announcement to members of the public and issued a news release, indicating that: 1) U.S. EPA proposes to select an interim remedy for this site, including fencing the contaminated portion of the site and providing alternative water supply to potentially affected homes; 2) The comment period for fencing and alternate water supply will end on August 31, 1992; 3) The comment period for the remaining portions of the remedy will remain open until further notice, in order to address community concerns. A coalition of various West Chester community groups and residents was formed after the July 29, 1992 public meeting in order to discuss th~pkinner Landfill cleanup and to meet with the U.S. EPA and Ohio EPA. This coalition includes representatives from'~he Township Trustees, the Chamber of Commerce, C.L.E.A.N;...the School Board, the Old West Chester Merchants Associatiort, the Union School PTA, the Home Builders Association, the Firefighters/service Group, and a number of Township Residents. The U.S. EPA and Ohio EPA have met several times with this coalition, and expect to meet with them in the future. ~. 'i SCOPE AND ROLE OF THE OPERABLE UNIT WITHIN THE OVERALL SITE STRATEGY The U.S. EPA has organized this project into two operable units. The first operable unit is an interim action to protect human health by limiting site access to prevent ingestion of and direct contact with contaminated soils, and to protect the potentially affected users of groundwater on and near to the site. The second operable unit will address source control measures, . and the remaining on-site contamination. This interim action operable unit is considered to be consistent with any conceivable overall site remedy..1..... ------- 4 SUMMARY OF SITE CHARACTERISTICS This description of site characteristics is limited to those site characteristics which relate directly to the interim remedy, i.e. the extent of soil contamination, and the potential for downgradient migration of groundwater contamination. The buried waste lagoon appears to be a source of groundwater contamination. Additional sources may exist elsewhere on the site. The groundwater in two wells, GW-20 and B-OS, located immediately adjacent to and downgradient from the lagoon, were the most severely impacted of wells tested during Phase II. Contaminants detected in these wells include 1,1-dichloroethane, 1,2-dichloroethane, 1,2-dichloroethene, 1,2-dichloropropane, chloroethane, ethylbenzene, chloroform, trichloroethene 1,3- dichlorobenzene, 1,4-dichlorobenzene, naphthalene and vinyl chloride. The flow of groundwater within the unconsolidated deposits (those deposits lying above the bedrock) on the site appears to be generally controlled by the surface topography, which in turn mirrors the bedrock topography. The groundwater surface maps indicate that the groundwater flows downgradient, along the same direction as the slope of the ground surface. The area encompassing the Skinners' residential well is separated from the waste lagoon by a groundwater divide. This means that groundwater would not be expected to flow, for example, from the buried waste lagoon area, across the groundwater divide, to the Skinners' residential well. The Skinners' residential well has been found to be contaminated with several volatile organic compounds at concentrations less than the drinking water standards. Therefore, it appears that there is a source of groundwater contamination within this area, other than the buried waste lagoon. The Proposed Plan indicated that this source would be identified as part of the overall site remedy. The fenced area encompasses the landfill and the buried waste lagoon, which the Remedial Investigation identified as the primary areas of contamination. SUMMARY OF SITE RISKS Because the Skinner Landfill accepted a variety of wastes since 1934 until it was closed in 1990, numerous chemicals have been detected at the site. Following the RI, an analysis was conducted to estimate the potential health or environmental problems that could result if the site was not cleaned up. This analysis is referred to as the Baseline Risk Assessment (RA). In this assessment, approximately 166 contaminants representing ------- ~ 5 essentially all classes of chemicals were evaluated for carrying through the risk assessment. Of the~~, 114 contaminants were retained from these chemical classes for use in assessing site risks. These chemicals can be found on Table 3-1 of the RA Report, and include inorganic, volatile and semi-volatile organic chemicals, pesticides, polychlorinated biphenyls (PCBs), polynuclear aromatic hydrocarbons (PAHs), dioxins and furans. Those contaminants contributing the most significantly to current and future site risks included: volatile organics such as carbon tetrachloride, vinyl chloride, benzene, chloroform, dichloroethene and bis (2-chloroethyl) ether; pesticides such as heptachlor, aldrin, dieldrin, chlordane, chlordene, and hexachlorobenzene; PCBs, specifically Arochlor 1254, and inorganics such as arsenic and cobalt. The most highly contaminated media included the soils of the buried waste lagoon. Lower levels of contamination were found in the remaining site-wide soils which included the buried pit area. Lower levels of contamination were also found in the ground water and in the sediments in Mill Creek, Skinner Creek, and the Duck and Diving Ponds. Additional contamination may be from drums located north of the buried waste lagoon which were sampled in 1976 and 1986. The remaining portions of the landfill contain smaller quantities of solid and industrial waste mixed with larger quantities of demolition materials. However, ground water monitoring wells located within the landfill indicate that the landfill is also a source of contamination. Leachate is created at this site when rain water or melting snow percolates through the waste lagoon and landfill. The majority of compounds in the waste lagoon are largely immobile, because they bind tightly to the clayey soils below the waste lagoon and are not dissolved by water. However, mobile VOC compounds in permeable zones beneath the waste lagoon have been detected. These compounds are apparently mobile in the water table and in perched ground water zones above impermeable layers. Contamination of the bedrock layer was minimal. The majority of ground water contamination in the unconsolidated sediments appears to originate from within the buried waste lagoon. Additional sources may exist to the north and east of the buried waste lagoon as well as upgradient of the Skinner's residential well in the buried valley. Two wells located immediately adjacent to, and downgradient from, the lagoon are the most impacted. These wells contain a wide variety of contaminants with the majority being volatile organic and chlorinated semi-volatile organic compounds. Three wells located within the landfill indicated elevated levels of primarily benzene. Ground water monitoring wells located downgradient of the waste lagoon and landfill, and adjacent to the East Fork of Mill Creek, show considerably fewer contaminants and at much lower concentrations. ~ ------- 6 Surface water contamination is minimal in all ponds and creeks. However, pond and creek sediments cor.~ain low levels of some semi-volatile organic compounds, PCBs, arsenic, and pesticides. The most likely reason for the contamination is due to surface water runoff from the site. The potential migration pathways for these contaminants include leaching from the soils to the ground water, movement of contaminated ground water to surface water and sediments, and volatilization of chemicals to air from water and soils. Sampling has indicated that concentrations of volatile chemicals in surface soils and water do not represent a significant source of concern for air. Additionally, the depth of contaminated soils in the waste lagoon limits the emission of these chemicals to air. Currently, the only evidence of contaminants potentially leaving the site through ground water migration is the detection of ethylbenzene at low levels located across the East Fork of Mill Creek from the buried lagoon. The only potential off-site routes of migration for surface water and surface water sediments are through the East Fork of Mill Creek and Skinner Creek. The leachate seeps and ground water discharges into the East Fork of Mill Creek appear to originate from within the buried waste lagoon and clearly indicate a pathway for off-site migration of contaminants. The RA showed that the potential routes of current and future exposure include: ingestion of and direct contact with contaminated soils; ingestion of affected ground water; dermal contact with ground water; inhalation of chemicals that volatilize from ground water to air during showering; and, ingestion of and direct contact with surface water and sediments during recreational activities. Inhalation of fugitive dust and volatile chemicals was also evaluated qualitatively as a potential exposure route but did not warrant a quantitative assessment because emissions from surface soil would likely be low. This is because the most contaminated portion of the site, the buried waste lagoon, is beneath up to .40 feet of demolition debris and is not considered a source of air risk under the current conditions. DESCRIPTION OF ALTERNATIVES The proposed plan for this site presented five alternatives. The first was a no action alternative, which is evaluated at all Superfund sites in order to assess the potential risk to the public which could occur if no cleanup was done. The other four alternatives evaluated a range of source control response options. However, each of the other four options included identical provisions for monitoring, fencing and provision of ------- ~ 7 alternate water supply. Therefore, only two alternatives for the fencing and alternate water supply ar~ discussed in this ROD. ALTERNATI:VE 1 NO ACTI:ON The Superfund program required that the "no action" alternative be considered at every site. Under this alternative, the U.S. EPA would take no action to control site access, or to provide alternate water supply to potentially affected residences. Obviously, there is no cost associated with the no action alternative. ALTERNATI:VE 2. FENCING AND PROVISION OF ALTERNATIVE WATER SUPPLY The portion of the site which was utilized for landfilling and the disposal of liquid wastes, as shoWn in Figure 2, will be enclosed by a 6' tall chainlink fence, topped by two strands of barbed wire. In order to minimize any potential interference between this interim remedy and any future action taken at this site, the fence line has been drawn to encompass the potential future boundaries of a cap, as described in the Proposed Plan. Gates will be installed where the fence intersects on-site roads, and will be wide enough to permit access to emergency vehicles. Keys will be provided to the local police and fire departments, and to any other'agencies identified by U.s. EPA. Signs will be installed on the fence, indicating the presence of Superfund chemical waste site. The signs will state: "Danger, Keep Out, United state Environmental Protection Agency Superfund Site". The fence will be periodically inspected, and repaired, if necessary. The fence will be kept locked to the maximum extent practicable. Those who use groundwater for drinking purposes, who are potentially impacted by migration of contaminated groundwater from the site will be offered alternative water supply, along with the current on-site residents. The' area of potential groundwater impact is shown in Figure 3. This area is based upon the projected rate and direction flow of groundwater from the site through the surficial deposits. Groundwater at the downgradient site boundary will be monitored for organic and inorganic contaminants on a quarterly basis. Implementation of this option will require the installation of several groundwater monitoring wells. Capital Cost: $160,000 Annual O&M Cost: $30,000 ------- 8 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES The remedial alternatives developed during the Feasibility study were evaluated by the U.s. EPA using the following 9 criteria. The advantages and disadvantages of each alternative were then compared to determine which alternative provided the best balance among these 9 criteria. These criteria are set forth in the National Contingency Plan, 40 CFR Part 300.430. 1. Overall Protection of Human Health and the Environment addresses whether of not a remedy provides adequate protection and describes how risks are eliminated, reduced or controlled through treatment, engineering controls or institutional controls. 2. ComDliance with ARARs addresses whether or not a remedy will meet all of the applicable or relevant and appropriate requirements (ARARs) of other environmental statutes and/or provide grounds for invoking a waiver. 3. Lona-term Effectiveness ability of a remedy to maintain health and the environment over met. .£!:.'I and Permanence refers to the reliable protection of human time once cleanup goals have been 4. Reduction of'Toxicitv. Mobilitv or Volume is the anticipated performa~ce of the treatment technologies a remedy may employ. '. 5. Short-term Effectiveness involves the period of time needed to achieve protection and any adverse impact on human health and the environment that may be posed during the construction and im~mentation period until cleanup goals are achieved. 6. ImDlementability is the technical and administrative feasibility of a remedy, including the availability of goods and services needed to implement the chosen solution. 7. Cost includes capital and operation and maintenance costs. 8. State AcceDtance indicates whether, based on its review of the RIfFS and Proposed Plan, the State of Ohio concurs, opposes, or has no comment on the preferred alternative. 9. Community AcceDtance will be assessed in the Record of Decision following a,review of the public comments received on the FS report and the Proposed Plan. ------- o 9 Each alternative was selected alternative alternatives compare follows. evaluated against these nine criteria. The is Alternative 2. A discussion of how the to each other based upon these criteria Overall Protection of Human Health and the Environment The fencing is designed to limit access of nearby residents to the contaminated portions of the site, and therefore is a positive contribution toward the overall protection of Human Health and the Environment. The groundwater-related portion of the interim remedy is designed to address the threat of offsite groundwater contamination, rather than any existing offsite groundwater contamination. As such, however, it provides protection of human health and the environment from the threat of offsite groundwater contamination. Compliance with ARARs Installation of groundwater monitoring wells will be performed in accordance with the pertinent portions of OAC 3745-9, Water Well Standards. There are: OAC 3745-9-01 Definitions OAC 3745-9-05 Construction of New Wells OAC 3745-9-06 Casing for New Wells OAC 3745-9-07 Surface Design of New Wells OAC 3745-9-09 Maintenance & Modification of Wells OAC 3745-9-10 Abandonment of Test Holes & Wells OAC 3745-9-11 Use of Wells for Disposal Any construction activities, provision of hook-ups to the local water mains, will be conducted in accordance with local construction codes. Lana-term Effectiveness and Permanence This interim remedy offers permanent, long-term protection to the potentially affected users of groundwater. Reduction of Toxicitv. Mobilitv or Volume This interim remedy does not address the contaminant source, and therefore does not provide for any reduction in toxicity, mobility or volume. Short-term Effectiveness This interim remedy is simple and may be implemented quickly, thus maximizing short-term effectiveness. ------- 10 ImDlementabilitv This interim remedy is easily implementable using proven, readily available technologies. Cost The cost of this interim remedy is commensurate with its benefits in terms of the other criteria. state AcceDtance The state of Ohio accepts this interim remedy. Communitv AcceDtance The Community appears to accept this interim remedy. Comments are summarized in the responsiveness summary. SUMMARY OF COMPARISON Under the No Action alternative, contamination could migrate from the site without being detected, and potentially could be consumed by humans. Also, humans could trespass onto the site and encounter contaminated soils. For these reasons, the No Action alternative is not considered to be protective of human health, and therefore is not a viable option for this site. Selected Remedy Alternative 2 The fencing, groundwater monitoring and provision of alternate water supply will provide for protection of public health in a very short time frame and for a reasonable cost, and is the preferred alternative for this interim action operable unit. This interim action will not exacerbate the existing situation and it is consistent with the goals of the final operable unit. STATUTORY DETERMINATIONS i \ Under its legal authorities, u.s. EPA's primary responsibility at Superfund sites is to undertake remedial actions that achieve .adequate protection of human health and the environment. In addition, section 121 of CERCLA establishes several other statutory requirements and preferences. These specify that when complete, the selected remedial action must comply with ARARs under Federal and State environmental laws, unless a statutory waiver is justified. The selected remedy must also be cost. effective and utilize permanent solutions and alternative ------- ~ 11 treatment or resource recovery technologies to the maximum extent practicable. Finally, the statute i~~ludes a preference for remedies that employ treatment that permanently and significantly reduce the toxicity, mobility or volume of hazardous substances, pollutants and contaminants. The following sections discuss how the selected remedy, where applicable, meets the statutory requirements and preferences. A. Protection of Human Health and the Environment The selected remedy provides for protection of human health by limiting the potential for consumption of contaminated drinking water within the potentially affected area and by limiting access to the most contaminated area. As a public water supply system, the selected remedy is a proven and reliable method of providing a permanent and safe drinking water supply through required treatment and monitoring. The remedial objective of this operable unit is protection of human health only. Protection of the environment will be achieved by future operable units that address contaminated groundwater and on-site sources of contamination. B. ComD1iance with ADp1icab1e or Relevant and ADDroDriate Reauirements (ARARs) All ARARs will be met for this operable unit remedial action. The RCRA Land Disposal Restrictions do not apply to this operable unit remedial action, because no contaminated soil will be dug up. Local construction codes will be followed. C. Cost-Effectiveness The selected remedy is cost-effective. D. utilization of Permanent Solutions and Alternate Treatment Technoloaies to the Maximum Extent Practicable U.S.EPA has determined that the selected remedy represents the maximum extent to which permanent solutions can be utilized in the most cost effective manner to address potential drinking water contamination in the affected area. U.S.EPA has determined that the selected remedy provides the best balance of tradeoffs in terms of short-term effectiveness, implementability, cost and State and community acceptance. The critieria of long-term effectiveness and permanence are met by the permanent hook-up of residences to a public water supply. This operable unit does not address the reduction in toxicity, mobility or volume achieved through treatment or the statutory ------- . 12 preference for treatment as a principal element of the selected remedy. Future operable units will ~?ecifically address the remediation of on-site sources and contaminated soils and groundwater with respect to applicable statutory requirements. E. Preference for Treatment Since the selected alternative does not involve any treatment, this operable unit does not address the preference for treatment. Again, this statutory preference will be evaluated in future operable units that specifically address contamination at the site. RESPONSIVENESS SUMMARY Appended to this ROD is the Responsiveness Summary which present background information, describes community involvement and categorizes the public comments received during the public comment period and U.S.EPA's responses to the comments. ------- Skinner Landfill + Fencing + WW Engineering & Science Key: Approximate Fence Location = - <0 c- --.- @ 0kr~~O 390 Scale in Feel 600 I IlgUlu 1 .? Topographic M;op Skinner Lalllilill \V,!sl CfIf'Sf(:1 Cl1n) ApI/I 1992 0.10. POOR QUALITY ORIGINAL ------- ~kmner LanOUli Precautionary provision of alternate water supply . Key: Approximate extent of site = D Off-site area to which alternate water supply will be offered = 0 ------- |