PB94-964315 EPA/ROD/R07-94/077 February 1995 EPA Superfund Record of Decision: Obee Road (O.U. 1), Hutchinson, KS 6/30/1994 ------- UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION VII 726 MINNESOTA AVENUE KANSAS CITY, KANSAS 66101 i | !,.;•• ' • " ,\ U \..: i '•• • ; • : ':J 0 * KEMORANDPM SUBJECT: Record of Decision for the Obee Road Landfill Subsite, Obee Road Superfund Site, Hutchinson, Kansas FROM: Michaer C^/sShderson, Acting Director Waste Management Division TO: Dennis Grams, P.E. Regional Administrator The attached Record of Decision presents the proposed remedy for the final remedial action at the subject subsite. This remedy will monitor the ground water at the Landfill Subsite on an annual basis and includes a contingency for further action if the monitoring indicates releases of contaminants above the Safe Drinking Water Act Maximum Contaminant Levels-MCLs. The remedy. . also provides for institutional controls to include access restrictions and deed restrictions. The selected remedy in this Record of Decision has been coordinated with the Office of Regional Counsel, the Office of Public Affairs, the Congressional and Intergovernmental Liaison, the Agency for Toxic Substances and Disease Registry and the Kansas Department of Health and Environment. On December 27, 1990, the remedy selection authority for the •Obee Road Landfill Subsite was delegated to you by Don R. Clay, Assistant Administrator. I recommend approval of the proposed remedy. Attachment RECYCLE . ------- OBEE ROAD LANDFILL SUBSITE OBEE ROAD SUPERFUND SITE RECORD OF DECISION DECLARATION SITE NAME AND LOCATION Obee Road Landfill Subsite Hutchinson, Kansas (Reno County) STATEMENT OF BASIS AND PURPOSE This decision document presents the selected final remedial action for ground water monitoring, institutional controls and provides a contingency for further action if the ground water monitoring detects contamination and a containment and treatment system needs to to be implemented at the Obee Road Landfill Subsite, Hutchinson, Kansas, chosen in accordance with the Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA), as amended by the Super fund Amendments and Reauthorization Act of 1986 (SARA), 42-U.S.C. Section 9601 et sea. . and, to the extent practicable, the National Oil and Hazardous Substances Pollution Contingency Plan (NCP), 40 CFR Part 300. This decision is based on the administrative record for the Obee Road Landfill Subsite, Hutchinson, Kansas. The United States Environmental Protection Agency (EPA) and the Kansas Department of Health and Environment (KDHE) agree on the selected remedy. ASSESSMENT OF THE SITE The actual or threatened release of hazardous substances at or from this site, if not addressed through the implementation of the response actions selected in this Record of Decision (ROD), may present an imminent and substantial endangerment to public health, welfare, or the environment. DESCRIPTION OF THE SELECTED REMEDY The Remedial Investigation/Focused Feasibility Study (RI/FFS), conducted by the Obee Road Potentially Responsible Party (PRP) Group from March, 1990 to February, 1994 at the Obee Road Landfill Subsite indicated essentially no risk at the site at the time of the RI but historical data indicated the landfill was a source of ground water contamination in the past and there may be a potential for future releases by leaching unknown sources within the ------- landfill. The selected remedy for the subsite is Institutional Controls/Ground Water Monitoring with a contingency for further action. This alternative includes: ground water monitoring, Landfill access restrictions, and Landfill deed restrictions with a contingency for further action. Ground water monitoring is used to detect contaminant presence and migration at the Site. The ground water monitoring program would include annual sampling for a five-year period with VOC analysis of the following monitoring wells: MW-9S (Upgradient) MW-5S (Downgradient) MW-3 (Landfill) MW-6 (Downgradient) MW-4 (Landfill) . MW-10S (Downgradient) MW-5 (Downgradient) MW-10D (Downgradient) A contingency for further action is also a part of the selected remedy in the event that ground water contamination increases in the future and is found to be migrating off-site at concentrations above the current Maximum Contaminant Levels (MCLs) under the Safe Drinking Water Act (SDWA) for aquifers which may be used for drinking water purposes. The contingency would include the evaluation of appropriate responses for the -containment and treatment of the ground water to meet the ARARS. The remedy under the contingency could "include extraction well(s) for containment and air stripping tower(s) for treatment of the extracted ground water. The effluent from the stripping towers would be governed by the National Pollutant Discharge Elimination System Permit and any additional treatment of exhaust vapors from the air stripper(s) would be determined after monitoring the vapors at the start-up of the air stripper(s). Access and deed restrictions include minimizing Landfill access by trespassers and preventing future development of the Landfill. These access and deed restrictions would be implemented by the City of Hutchinson, who currently owns the landfill property. This reduces the potential for contaminant exposure from contact.with or disturbance of .the Landfill cover and its contents. 'Fencing and access restrictions are already in place at the Landfill. The selected remedy will protect human health and the environment by using ground water monitoring to detect future contamination of ground water at the Site; by responding with additional action to contain and treat the contamination if any is detected; and by establishing deed restrictions which would prevent disturbance of the Landfill cover and its contents. STATUTORY DETERMINATIONS The selected remedy is protective of human health and the environment, complies with Federal and State requirements that are legally applicable or relevant and appropriate to the remedial action, and is cost-effective. This remedy utilizes permanent ------- solutions and because this remedy monitors the ground water so as to detect any hazardous substances remaining on-site above levels that allow for unlimited use and unrestricted exposure, a review will be conducted no less often than every five years after commencement of remedial action to ensure that the remedy continues to provide adequate protection of human health .and the environment. ~, P. E s -•' w7 VT D&te RegionalAdministrator U.S. EPA - Region VII • ------- RECORD OF DECISION % OBEE ROAD LANDFILL SUBSITE Hutchinson. Kansas JUNE 1994 U.S. Environmental Protection Agency Region VII 726 Minnesota Avenue Kansas City, Kansas 66101 ------- TABLE OF CONTENTS 1.0 SITE BACKGROUND 1 1.1 Site Location 1 1.2 Physical Setting 1 1.3 History 2 1.4 Past Investigations and Remedial Activities 2 1.5 Highlights of Community Participation 4 1.6 Summary of the Remedial Investigation 5 1.6.1 Activities 5 1.6.2 Conclusions 6 2.0 SUMMARY OF SITE RISKS 7 2.1 The Baseline Risk Assessment 7 2.2 Contaminant Transport 9 2.3 Ecological Risks 10 3.0 SCOPE AND ROLE OF RESPONSE ACTION 10 4.0 SUMMARY OF ALTERNATIVES ' 11' 4.1 Screening and Formulation of Alternatives 11 4.2 Detailed Evaluation of Remedial Alternatives 11 5.0 EVALUATION OF ALTERNATIVES 12 5.1 Summary of Evaluation Criteria . 12 5.2 Evaluation of the Alternatives 14 6.0 SELECTED REMEDY 17 7.0 STATUTORY DETERMINATIONS IB 8.0 RESPONSIVENESS SUMMARY 21 ------- ATTACHMENTS Attachment I - Attachment II - Glossary of Terms Comment and Response Letters FIGURES Figure I - Site Location Map Figure 2.- Obee Road Site Area and Land Use Map Figure 3 - Monitoring Well Locations in Obee Road Site Area Figure 4 - Analytical Results of Soil Samples From Landfill Figure 5 - VOCs in Ground Water TABLES Table 1 - KDHE Ground Water Sampling Results Table 2 - Estimated Costs for the Selected Remedy ------- 1.0 SITE BACKGROUND 1.1 SITE LOCATION The Obee Road Landfill Subsite is a part of the Obee Road Superfund Site located within the area of the former City of Hutchinson Landfill east of Hutchinson, Kansas. The approximate boundaries of the Subsite are defined as "the eastern one-half of Section 10, Township 23 S, Range 5 W, Reno County, Kansas, and those areas south of the eastern one-half of Section 10 up to 100 feet south of 4th Street (see Figure 2) . The landfill area is currently covered with vegetation and encompasses approximately 80 acres. The relationship of the Landfill Subsite to the Obee Road Superfund Site is also shown on Figure 2. The Landfill Subsite is bounded by the Hutchinson 'Municipal Airport along the north and west, Obee Road and a residential area along the east, and residential/agricultural areas to the south. The Obee School, an elementary school, is located immediately south of the Landfill Subsite. A large area of residences is located further south of the Landfill Subsite and includes about 102 homes and 280 residents. 1.2 PHYSICAL SETTING The Obee Road Superfund Site is located in -the Great Bend. • Lowland within the Great Bend Prairie physiographic province. The Site lies on a low terrace approximately 5 miles north of . the Arkansas River. The topography at the Site does not vary greatly. Northeast of the City of Hutchinson and adjacent to the northeast portion of the Site is a belt of sand dunes which marks the boundary of the north side of the Arkansas River Valley. The former landfill area is currently fenced with chain-link fencing, and is heavily vegetated by brush and trees with minor areas of subsidence apparently caused by landfill operations. Ground water in the region comes primarily from unconsolidated alluvial deposits of Quaternary age. These deposits overlay Permian bedrock in the Site area. The depth of the alluvial deposits ranges from 28 to 66 feet; and the average depth to ground water is 17 feet. The direction of ground water flow in the alluvial aquifer at the Site is generally southeast, although, there is significant variation in the northern site area. In the northeast portion of the site, the ground water flows to the southwest down the bedrock surface slope then turns to the southeast. ------- 1.3 HISTORY The now-closed City of Hutchinson Landfill was operated from 1953 to 1968 and was the only public disposal site in Hutchinson during that time. Prior to closure, the landfill received typical domestic wastes and unknown quantities and types of industrial wastes. Disposal generally occurred on a daily basis, with the wastes being placed in trenches approximately 14 to 15 feet in depth. There was no differentiation between the disposal of liquid or solid wastes. No records or reports have been found to document the design, use, or closure of the landfill. As a result of investigations, which began in 1983, the Kansas Department of Health and Environment (KDHE) proposed the Obee Road Site for inclusion onto the National Priority List (NPL) in August 1985. The Obee Road Site, which encompasses both the Obee Landfill Subsite and the Airport Road Subsite (see Figure 2), was placed on the NPL on July 22, 1987 by EPA pursuant to its authority under CERCLA as amended by SARA. A consent agreement between KDHE and the Obee Road PRP Group was executed on March 27, 1990 to perform a Remedial Investigation/Feasibility Study (RI/FS) for the Obee Road Site. The consent agreement was later amended in March of 1993 to focus only on the Obee Landfill Subsite. The amendment was made due to the division of the Obee Road Site into two subsites following KDHE and EPA review of the results of the Phase II investigation. The data from this investigation, performed under the Obee Road Site RI, indicated that the Landfill area could clearly be separated from the area of 4th and Airport Road. The Landfill was not found to be a significant .spurce of ground water contamination, but KDHE and EPA determined that the 4th and Airport Road area required further investigation. 1.4 PAST INVESTIGATIONS KDHE has conducted periodic investigations and sampling activities in the vicinity of the Obee Road Site since July 1983. These investigations were initiated as a result of a citizen's complaint of disagreeable tastes and odors in a domestic water well. KDHE's sampling of selected private wells identified volatile organic compounds (VOCs) in the aquifer, which at the time provided a ground water supply for private domestic wells in the area. City water supply wells are located upgradient and approximately two-plus miles from the Obee Road site area. ------- In August and September of 1983, KDHE sampled a number of private wells in the site area. All of the ground water samples were analyzed for VOCs. Several of the samples were analyzed for inorganics, heavy metals, polychlorinated biphenyls (PCBs)/pesticides, and/or acid-extractable and base- neutral compounds. An expanded sampling effort of private wells was conducted in January 1984, with the samples being analyzed for inorganics, heavy metals and VOCs. The results of the KDHE sampling of private wells in 1983 and 1984 indicated that VOCs were present in ground water in the Site area. The following VOCs were detected at levels ranging from detected (but not quantifiable) to 12 micrograms per liter (ug/1) : vinyl chloride,. dichloromethane, 1,1- dichloromethane, trans 1,2-dichloroethylene, trichloromethane, 1,1,1-trichloroethane, tetrachloromethane, trichloroethylene, benzene, dibromochloromethane, 1,1,2,2-tetrachloroethylene, toluene, and chlorobenzene. Many of these VOCs were detected at levels greater than the allowable State (Kansas Action Levels or KALs) and federal (Maximum Contaminant Levels or MCLs) drinking water standards. The majority of area residences and the Obee Elementary School, which had previously used private water wells for domestic purposes, have been connected to the public water supply system. The remaining residents have been encouraged to hook up to the system and KDHE is working with the county health department to establish a monitoring program for outlying residents still on private water wells. No contamination above MCLs has been detected in any well water currently being used by residents in the area. In July and August 1984, KDHE installed eight monitoring wells in the Site vicinity (see Figure 3) . Four wells were screened in the intermediate portion of the aquifer and four wells were screened in the interval just above bedrock. The KDHE monitoring wells were sampled in August 1984, April and May 1985, and August. 1986 for.VOCs and/or.inorganics and heavy metals. The results of the analyses of samples for the KDHE monitoring wells confirmed VOC contamination in the ground water (see Table 1). KDHE completed a Preliminary Assessment (PA) on July 31, 1987. The results of the PA concluded that the extent of ground water contamination had not been sufficiently characterized and that the former Hutchinson City Landfill was one of the potential sources of the ground water contamination found in the area. A shallow soil gas survey was conducted by Tracer'Research Corporation in August 1986 under the direction of KDHE. The purpose of the soil gas survey was to determine the approximate extent and magnitude of VOC contamination in the vicinity of the Obee Road site. The soil gas survey results ------- were presented to KDHE by Tracer Research Corporation in a report entitled "Soil Gas Survey of Five Kansas Sites", dated August 1986. The results of the survey indicate that VOCs may be present in the vicinity of the Landfill and near the 4th Avenue and Airport Road intersection. A separate investigation is currently underway at another site, East 4th Street Facility (Cessna/Eaton), which is about a quarter mile south of 4th Avenue and Airport Road on the west side (Figure 2). Further investigation is necessary for the Airport Road Subsite of the Obee Road Site and'the East 4th Street Facility Site, to determine the source(s) and extent of contamination in these areas. 1.5 HIGHLIGHTS OF COMMUNITY PARTICIPATION ' Community participation was provided in accordance with CERCLA, as amended by SARA and the National Contingency Plan (NCP). Community participation highlights include the availability of several key documents in the administrative record, a public comment period and a public hearing. A community relations plan for the Obee Road Superfund Sites completed and approved in May of 1991. .This .document lists contacts and interested parties throughout government and the- local community and specifies the community relations activities expected to be undertaken during the remedial process. It also establishes communication pathways to ensure dissemination of pertinent information. The administrative record for Obee Road Site was released in April of 1991. The records have been made available to the public at the following addresses: Kansas Department of Health and Environment Bureau.of Environmental Remediation ' • • Forbes Field, Building 740 Topeka, Kansas 66620-7500 913-296-3393 Hutchinson Public Library 901 North Main Hutchinson, Kansas United States Environmental Protection Agency Region VII 726 Minnesota Avenue Kansas City, Kansas 66101 913-551-7000 ------- A press release was issued on March 3, 1994 announcing the release of the Proposed Plan, commencement of the public comment period and notice of the Public Hearing for the Obee Road Landfill Subsite. The Public Hearing was held on March 31, 1994 to present the Proposed Plan and to receive comments. At this meeting representatives of EPA and KDHE were available to answer questions and record comments concerning the Proposed Plan. All comments received by EPA and KDHE throughout the comment period are addressed in the Responsiveness Summary in this Recprd of Decision. 1.6 SUMMARY OF THE REMEDIAL INVESTIGATION 1.6.1 ACTIVITIES The objectives of the RI included: (1) the definition of the nature and extent of contamination in ground water emanating from the Landfill; (2) the definition of the nature and extent of contamination in the surface soils at the Landfill; (3) the identification of any possible sources of contamination; (4) the characterization of the Site geohydrology; and (5) evaluation of the Site's existing and potential threat to human health and the'environment. • The RI activities were divided into three phases. Phase I included preparation of the Workplan and other planning documents necessary for the implementation of the RI. The KDHE monitoring wells were sampled in February 1991 (Phase I) to aid in developing the scope for the RI/FS (see Table 1 for results). Phase II included initial field investigation of soil and ground water. Phase III included further field investigation of soil and ground water and was necessary to characterize contamination at the Site. During the Phase II investigation, six landfill soil samples were collected in the upper 1 foot of soil cover and were analyzed for VOCs, semi-volatile organic compounds (SVOCs),• metals, and pesticides/PCBs. The purpose of the collection of soil samples in the Landfill cover was to evaluate the level of contaminants in the .surface soil to .determine their possible effects on human health and the environment, and to evaluate the physical integrity of the soil material covering the Landfill. During the Phase III investigation, six shallow soil samples were collected from the Landfill and analyzed for PCBs. Boring LB-1 (Figure 3), where Arochlor-1254 was detected in the Phase II investigation, was resampled at a shallow depth ------- and samples were also collected from four additional locations in the vicinity of Boring LB-1. These samples were taken from a depth of about two to three inches. Eight monitoring wells were constructed during the RI to screen different portions of the aquifer to determine the vertical, as well as lateral, distribution of dissolved contaminants. Six shallow wells and two deep wells were constructed in addition to the three KDHE intermediate wells and .two KDHE deep wells (see Figure 3). Three wells (MW-8S, MW-9S, MW-14S, MW-7, and MW-14D) upgradient of the Landfill, five wells (MW-5S, MW-10S, MW-17S, MW-5, MW-10D) downgradient of the Landfill, and three wells (MW-4, MW-6, MW-3) underneath the Landfill, were used to characterize ground water contamination at the Site. Two separate rounds of ground water samples were collected from the monitoring wells constructed during the RI and the five previously constructed KDHE monitoring wells (MW-4, MW-6, MW-3, MW-5, and MW-7). These samples were analyzed for VOCs during the RI. Phase II ground water sampling was conducted .from September 18 to October 15, 1991, and Phase III sampling was conducted from May 11 to May 14, 1992. Samples were collected from wells MW-5S (downgradient) and MW-8S (upgradient) and analyzed for PCBs, pesticides, SVOCs, metals (filtered and unfiltered), and total suspended solids during .the Phase II investigation. No samples were collected for metals analyses during the Phase III investigation. In addition, six water table borings were sampled and analyzed for VOCs during Phase II (also indicated on Figure 3). 1.6.2 CONCLUSIONS Tetrachloroethene (PCE) was detected in all Landfill soil samples at levels ranging from 13 to 54 ug/kg. Levels of metals detected in the Landfill cover material are within established ranges of metals in uncontaminated soils. No pesticides were detected in-any shallow Landfill samples. The PCB, Arochlor-1254, was detected in the sample analyzed from Boring LB-l at a level of 1200 ug/Kg. PCBs were not detected in any other samples during the Phase II investigation. No PCBs were detected in the Phase III soil samples. Figure 4 illustrates the locations and results of the soil samples. RI results for PCBs in soil indicate that the presence of PCBs in the soil cover at the Landfill is limited to an isolated occurrence at a depth of greater than. 6 inches below ground surface. Although the PCE detected in the soil is probably evidence of past waste disposal at the Landfill, a pattern was not apparent in the lateral distribution of PCE in the soil. ------- The Phase II ground water sampling results indicated low levels of the common laboratory contaminants methylene chloride and acetone in six well samples, which included one upgradient sample. Two trip blank samples also contained low levels of methylene chloride and acetone. Benzene was detected in samples from MW-4 and MW-3 at levels of 1 ug/1 and 3 ug/I, respectively. Chlorobenzene was detected in the sample from MW-3 at a level of 4 ug/1. No other VOCs were detected in any of the samples. The SVOC, bis(2-ethylhexl)phthalate, a common laboratory contaminant, was detected at low levels in both ground water samples analyzed during Phase II. These levels were considered insignificant and no further analyses for SVOCs was considered necessary. PCBs and .pesticides were not detected in ground water samples during Phase II. No further analyses for pesticides were considered necessary. However, since PCBs were detected in soil samples at the Landfill, further samples were collected at wells MW-10S and MW-3 and analyzed for PCBs. The Phase III ground water sampling results also indicated low levels of the common laboratory contaminant methylene chloride in three well samples. Vinyl chloride was detected at a level of 2 ug/1 in upgradient well MW-9S. No other VOCs were detected in any of the samples. Figure 5 illustrates the VOCs detected in ground water samples during the RI. No PCBs were dete'cted in the two samples analyzed during Phase III. Some of the metals found in the unfiltered ground water samples were at levels exceeding the KALs and MCLs for drinking water. However, since these levels were present in samples from upgradient and downgradient wells, it appears that the Site does not significantly contribute to the metals found in the unfiltered ground water samples. Laboratory results for filtered samples were all below the KALs and MCLs, indicating that sediment in the unfiltered samples contributed significantly to the. findings. 2.0 SUMMARY OF SITE RISKS 2.1 THE BASELINE RISK ASSESSMENT As part of the RI, a baseline Risk Assessment (BRA) was prepared for the Site. The risk assessment was carried out to characterize', in the absence of remedial action (i.e., the "no-action" alternative), the current and potential threats to human health and the environment that may be posed by contaminants migrating in ground water, released to the air, leaching through the soil, or remaining in the soil, or bioaccumulating in the food chain. ------- The baseline risk assessment is an evaluation of the potential threat to human health and the environment in the absence of any remedial action. It provides information to help determine whether remedial action is necessary at the site. A baseline risk assessment was conducted for this site to determine the potential effects on human health and the environment. One of the chemicals of concern identified and evaluated for the . Site included tetrachloroethylene (PCE) for soil. Contaminant levels in ground water samples at the Site were found to be within the State and federal drinking water standards. Therefore, chemicals of concern for ground water (vinyl chloride and methylene chloride) were evaluated using ground water transport modeling to determine their potential for migration.to off-site areas. Pathways by which humans could be exposed to the chemicals of concern at the Site were evaluated based on reasonable assumptions about current and future land uses. Since access to the Landfill/airport area is restricted by 8-foot fencing, the number and types of people who may be directly exposed to soil at the Landfill are limited. However, the potential for trespassing was not eliminated entirely. None of the chemicals at the Landfill were detected .in surficial soil, and' since excavation by a trespasser was. considered unlikely, dermal contact with or ingestion of chemicals of potential concern were not considered as pathways of concern. Dust generation at the Landfill is not considered significant since the Landfill is well vegetated. Therefore, inhalation of chemicals in dust particles was not considered a likely exposure pathway. The only pathway evaluated for the risk assessment calculations was inhalation of volatiles escaping from subsurface soil by the trespasser and resident scenarios. These were evaluated according to current and future exposure probabilities. A Hazard Index (HI) was calculated for each pathway evaluated.- A HI of less than 1 indicates that the noncarcinogenic risks associated with that pathway are low. The hazard index calculated for inhalation of PCE by a child trespasser is 0.0000002 (2x10-7) or 2E-7 in scientific notation. Since there is no other suspected exposure pathway, this is also the total HI. The HI calculated for a child resident potentially exposed to PCE vapors migrating off site in the air is 6E-7. Therefore adverse noncancer health effects for a child trespasser or nearby resident are not expected since the HI is well below 1. ------- The carcinogenic risks were.'also calculated for all identified pathways at the Site. The carcinogenic risk from exposure to a chemical is described in terms of the probability that an individual exposed for his/her entire lifetime will develop cancer. Risk estimates are presented as excess cancer risk per unit of population. For example, a risk estimate of 1 X 10-4 is equivalent to a risk of one excess occurrence of cancer per 10,000 individuals in a given population. The -total cancer risk associated with exposure for a child trespasser for inhalation of vapor-phase PCE is 3E-12, which is far below a level of health concern. The pathway and total cancer risk (including the residential scenario) for inhalation of vapor phase PCE is 1E-11, and is again well below a level of health concern. The findings of the baseline Risk Assessment for the site data indicate that there are essentially no risks to human health or the environment according to current Site conditions. 2.2 CONTAMINANT TRANSPORT The potential source of contaminants is the area of the former City Landfill where unknown types and quantities of waste were disposed. There are many physical, chemical, and biological processes which may affect the transport and fate of contaminants in the soil and ground water. The RI evaluated these processes for each contaminant of concern in order'to determine the potential for migration of contaminants from the Site. PCE was detected at low levels in the Landfill cover soil. These levels are expected to decrease in the future primarily due to volatilization to the air. Leaching of PCE into ground water may also occur. However, due to the low levels detected at the Site, the rate of release is not expected to pose a ground water or air exposure concern. The PCB, Arochlor-1254, was detected under the Landfill soil cover. However, follow-up sampling indicated that this occurrence was isolated. The physical and chemical characteristics for Arochlor-1254 include a very low solubility in water and a strong tendency to adsorb to soil. Therefore, this contaminant is not expected to leach into ground water. The probable fate of Arochlor-1254 will be to remain relatively immobile in the soil. Vinyl chloride and methylene chloride were detected in ground water at low levels. Although these compounds have medium to high tendencies to volatilize to air, the relatively low levels found in the ground water and in the fine-grained material above the water table would limit the movement from ------- the ground water to air. Since these soluble compounds are relatively mobile in ground water, contaminant transport modeling was performed to assess their potential occurrence at downgradient locations. The closest potential receptor location evaluated during the study was the Obee Elementary School. The model results indicated that the levels of vinyl chloride and methylene chloride would be insignificant (undetectable) by the time the contaminant migrates to the closest receptor. 2.3 ECOLOGICAL RISKS A biological survey of the Site and adjacent areas was conducted to describe the potential receptors and the overlying ecology of the area. .The survey was performed by walking the Site, recording plant and animal species present, and making general observations on plant community successional stages (range condition), soil series, and soil condition. In addition, a review of pertinent literature was made. The primary contaminant threat to plant and wildlife species at the Site are PCBs found in the soil. Although there is very limited data concerning the effect of PCBs on plants and wildlife, the general information indicates that the level and isolated incidence of the contaminant would not threaten the existence of the current plant and wildlife population. All of the threatened or endangered species for the county are migratory birds. These birds, most likely, would be present in the vicinity of lakes, rivers, streams, and wetlands, of which the Site contains only narrow, intermittent drainage ditches. Further, the risk to aquatic life from contaminants found at the Site is not of concern since there are no apparent transport mechanisms that could account for movement of significant quantities of the contaminants to nearby aquatic communities. 3.0 SCOPE AND ROLE OF RESPONSE ACTION As discussed in the Baseline Risk Assessment the conditions existing at the time of the RI indicated that essentially no risk exists at the site but the remedial response objectives were developed for the following reasons: / Historical KDHE sampling data has indicated the Landfill may have been a source of ground water contamination in the past. Since the materials disposed of in the Landfill are unknown, there may be a potential for future leaching from the 10 ------- Landfill. Therefore the following remedial response objectives have been established: To monitor so as to detect future ground water contamination, if it occurs, before it migrates off the Landfill site. If contamination is detected a remedial response action will be implemented to contain and treat the ground water contamination. To minimize public access and prevent future development of. the Landfill, thereby minimizing disturbance of both the surface soils and landfilled materials. 4.0 SUMMARY OF ALTERNATIVES 4.1 SCREENING AND FORMULATION OF ALTERNATIVES The results of the Remedial Investigation (RI) indicated that essentially no risk existed at the site at the time of the RI. Since historical data indicated the landfill was a source of ground water contamination in the past and there may be a potential for future releases by leaching unknown sources within the landfill, EPA and KDHE determined.that a Focused . Feasibility Study (FFS), which examined a more limited range of remedial alternatives, was appropriate for the Obee Road Landfill Subsite. The FFS evaluates two response actions which could be applied to the present conditions at the Subsite. The response actions include: (1) no action; and (2) institutional controls/ground water monitoring with the contingency for further action if the monitoring shows releases to the ground water. The screening criteria used for the analysis included effectiveness, implementability, and cost of the remedial action alternative. The remedial alternatives selected for detailed evaluation are presented below. - No Action Institutional Controls/Ground Water Monitoring with a Contingency for Further Action 4.2 DETAILED EVALUATION OF REMEDIAL ACTION ALTERNATIVES The two alternatives described above were evaluated and screened based on the following three criteria: - Effectiveness Evaluate the ability of the process option to handle 11 ------- the estimated .areas of volumes of contaminated media Potential impacts on human health and the environment during implementation of the process Reliability of the process for the Site contaminants Implementability Technical feasibility of process Administrative feasibility of process - Cost Capital costs Operation and Maintenance (p&M) costs Institutional controls/ground water monitoring will achieve the remedial action objectives established for the Site. Both selected general response actions have high potential iitiplementability and are cost-effective approaches for the level of protection offered by each. Both remedial options will be evaluated further for this Site.' 5.0 EVALUATION OF ALTERNATIVES 5.1 SUMMARY OF EVALUATION CRITERIA The following section presents a summary of the criteria used to evaluate the remedial action alternatives. The National Oil and Hazardous Substances Pollution Contingency Plan (NCP) has established nine criteria to evaluate remedial alternatives. These criteria serve as the basis for conducting detailed analyses during the FFS and subsequently are used to determine the appropriate remedy for the Site. 5.1.1. PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT This criterion addresses whether or/not a remedy provides adequate protection and describes how risks posed through each pathway are eliminated, reduced or controlled through treatment, engineering controls, or institutional controls. 5.1.2. COMPLIANCE WITH ARARS This criterion addresses whether or not a remedy. will meet all of the applicable or relevant and appropriate requirements' (ARARs) of other Federal, State or other applicable laws and regulations. ARARs may be grouped into three different categories. Chemical-specific ARARs are standards which dictate clean-up levels for specific hazardous substances. Action-specific ARARs are 12 ------- requirements which set standards for clean-up practices. Location-specific ARARs involve the consideration of site-specific geographic, topographic, or other factors dealing with the physical characteristics of the site. Potential ARARs are listed in Section 6.2.2. 5.1.3. LONG-TERM EFFECTIVENESS AND PERMANENCE This criterion refers to the ability of a remedy to maintain reliable protection of human health and the environment over time once cleanup goals have been met. 5.1.4. REDUCTION OF TOXICITY, MOBILITY, OR VOLUME This criterion reviews the anticipated performance of the treatment technologies a remedy may employ. 5.1.5. SHORT-TERM EFFECTIVENESS This criterion addresses the period of time needed to achieve protection, and any adverse impacts on human health and the environment that may be posed during the construction and implementation period until cleanup goals are achieved. 5.1.6. IMPLEMENTABILITY This Criterion refers to the technical and administrative feasibility of a remedy, including the availability of materials and services needed to implement a particular option. 5.1.7. COST This criterion evaluates the estimated capital cost, operation and maintenance costs, and net present worth costs. 5.1.'8. STATE AND SUPPORT AGENCY ACCEPTANCE This criterion discusses whether, based on their review of the RI/FFS and Proposed Plan, the agencies concur with, oppose, or have no comment on the preferred alternative at the present time. 5.1.9. COMMUNITY ACCEPTANCE This criterion will be assessed in the ROD following review of the public comments received on the RI/FFS reports, the administrative record, and the Proposed Plan. 13 ------- 5.2 EVALUATION OF THE ALTERNATIVES A detailed analysis of the remedial alternatives was conducted, consisting of an assessment of the individual alternatives against each of the nine criteria and a comparative analysis that focused on the relative performance of each alternative against those criteria. As a result of this detailed analysis, KDHE and EPA have determined that the Institutional Controls/Ground Water Monitoring with a contingency for further action Alternative provides the best balance among the alternatives with respect to the criteria. 5.2.1 OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT Although there were no current risks associated with the Subsite, the No Action Alternative would not provide additional protection of human health and the environment should future releases occur. The Institutional Controls/Ground Water Monitoring with a contingency for further action alternative would provide an increased level of protection of human health and the environment by providing for detection, containment and treatment of any future ground water contamination, thus preventing future consumption of contaminated ground water. In addition, overall protection of human health and the environment ' would be achieved, by providing for appropriate land use in the future, thus preventing future contact with' the Landfill and its contents. 5.2.2 COMPLIANCE WITH ARARs The No Action Alternative would not provide for any compliance with any ARARs. The Institutional Controls/Ground Water Monitoring with a contingency for further action Alternative provides a method for compliance with ARARs if additional containment and treatment of the ground water is necessary. The primary ARARs that would be applicable to the Obee Road Landfill Subsite if further action is necessary and involves the containment and tr'eatment of ground water would include: 1) Maximum Contaminant Levels (MCLs) as promulgated under the Safe Drinking Water Act .are the relevant and appropriate standards for remediation of contaminated groundwater. MCLs are chemical-specific ARARs. 2) Effluent limitation guidelines as governed by the Clean Water Act through the National Pollutant Discharge Elimination System (NPDES) are ARARs for any discharge of treated water resulting from site remediation activities. NPDES effluent guidelines are also chemical-specific 14 ------- ARARS. 3) No specific ARARs, other than state reporting requirements, currently exist for air emissions from the ground water stripping towers. However, the preferred alternative provides for air monitoring to ensure the health and safety of any exposed population. 5.2.3 LONG TERM EFFECTIVENESS AND PERMANENCE The long-term effectiveness of the No Action Alternative would be unknown since any future leaching of contaminants into the ground water or disturbance of the Landfill cover would not be monitored. The Institutional Controls/Ground Water Monitoring with a contingency for further action Alternative, would provide long-term effectiveness by continuous monitoring of the ground water, and by providing for additional action for containment and treatment of contaminated ground water should any future releases by detected. The preferred alternative also provides long-term effectiveness by implementing deed restrictions. The permanence criterion would not apply to the No Action Alternative, since no action would be taken. The Institutional Controls/Ground Water Monitoring with a contingency for.further action Alternative provides 'a greater degree of permanence by ensuring that any future release of contaminated ground water will be detected and that the extracted ground water would be treated to remove the contaminants. The preferred alternative also provides a relatively higher degree of permanence by restricting land use in the Landfill area and by restricting access to the property. 5.2.4 REDUCTION OF TOXICITY, MOBILITY, OR VOLUME The No Action Alternative would not effect the reduction of toxicity, mobility, or volume of contaminants since contaminants are below levels of concern as demonstrated in the RI report. The Institutional Controls/Ground Water Monitoring with a contingency for further action Alternative would only effect the reduction of toxicity, mobility .or volume if contaminants are detected and actions are taken to contain and treat the ground water. Then the contingency action would reduce the toxicity of the contaminants by .extracting the ground water and removing the contaminants. In addition, the mobility and volume of the contaminants within the ground water would be reduced by the extraction of the ground water in that the pumping action would prevent the contaminants from migrating from the area (mobility) and reducing the 15 ------- volume of the contaminants by treating the extracted water. 5.2.5 SHORT TERM EFFECTIVENESS The short term effectiveness of the No Action Alternative would be unknown since no ground water monitoring or institutional controls would be in place to determine the short term effectiveness of this alternative. The Institutional Controls/Ground Water Monitoring with a contingency for further action Alternative would provide for short term effectiveness by immediately implementing ground water monitoring and ensuring that contaminated ground water will be detected, contained and treated. In addition, deed restrictions and fencing provide good short-term effectiveness in that the Landfill and its contents'will not be disturbed. • ' 5.2.6 IMPLEMENTABILITY Both the No Action Alternative and the Institutional Controls/Ground Water Monitoring with a contingency for further action Alternative would be easily implementable. The preferred alternative is somewhat more difficult to implement but monitoring and (if necessary) containment and treatment are well-proven technologies that have been completed successfully at other-sites. • 5.2.7 COST The No Action Alternative would have no associated cost. The estimated cost of the Institutional Controls/Ground Water Monitoring Alternative is $100,000 for five years of monitoring. If the contingency to contain and treat ground water is initiated then a additional costs would be added to this estimate. The amount of any additional costs would vary depending upon several variables, including the number of extraction wells, air strippers or other equipment needed to implement the contingency, as well as the amount of time the system operates. 5.2.8 STATE AND SUPPORT AGENCY ACCEPTANCE The KDHE and the EPA have support the preferred alterative. 5.2.9 COMMUNITY ACCEPTANCE Comments were received during the comment period and reviewed. Summaries of those comments and EPA's responses are in Section 8.0. 16 ------- 6.0 SELECTED REMEDY The selected remedy for the Site is Institutional Controls/Ground Water Monitoring with a contingency for further action. This remedy includes: ground water monitoring, Landfill access restrictions, and Landfill deed restrictions with a contingency for further action. Ground water monitoring is used to detect contaminant presence and migration at the Site. The ground water monitoring program would include annual sampling for a five-year period with VOC analysis of the following monitoring wells: MW-9S (Upgradient) MW-5S (Downgradient) MW-3 (Landfill) MW-6 (Downgradient) MW-4 (Landfill) MW-10S (Downgradient) MW-5 (Downgradient) MW-10D (Downgradient) A contingency for further action is also a part of the selected remedy in the event that ground water contamination increases in the future and is found to be migrating off-site at concentrations above the current Maximum Contaminant Levels (MCLs) under the Safe Drinking Water Act (SDWA) for aquifers which may be used for drinking water purposes. The contingency would include the evaluation of appropriate responses for the containment and treatment of the ground water to meet the ARARS. The remedy under the contingency could include extraction well(s) for containment and air stripping tower(s) for treatment of the extracted ground water. The effluent from the stripping towers would be governed by the National Pollutant Discharge Elimination System Permit and any additional treatment of exhaust vapors from the air stripper(s) would be determined after monitoring the vapors at the start-up of the air stripper(s). Access and deed restrictions include minimizing Landfill access by trespassers and preventing future development of the Landfill. These access and deed restrictions would be implemented by the City of Hutchinson, who currently owns the landfill property. This reduces the potential for contaminant exposure from contact with or disturbance of the Landfill cover and its contents. Fencing and access restrictions are already in place at the Landfill. The selected remedy would protect human health and the environment by using ground water monitoring to detect future contamination of ground water at the Site; by responding with additional action to contain and treat the contamination if any is detected; and by establishing deed restrictions which would prevent disturbance of the Landfill cover and its contents. Cost estimates for the selected remedy are given in Table 2. After five years, the appropriateness of the ground water monitoring program would be evaluated by KDHE and EPA. If no additional contamination above MCLs and/or KALs is detected after 17 ------- five years of ground water monitoring, EPA and KDHE would consider ceasing the ground water monitoring program at that time. Landfill access and deed restrictions would continue to remain in effect. 7.0 STATUTORY DETERMINATIONS Under its legal authorities, the Environmental Protection Agency's primary responsibility at Superfund sites is to undertake remedial .actions that achieve 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 for this site must comply with applicable or relevant and appropriate environmental laws unless a statutory waiver is justified. The selected remedy also must be cost effective and utilize permanent solutions and alternative treatment technologies or resource recovery technologies to the maximum extent practicable. Finally, the statute includes a preference for remedies that employ treatment that permanently and significantly reduce the volume, toxicity or mobility of hazardous wastes as their principal element. The following sections discuss how the selected remedy meets these statutory requirements. 1. Protection of Human Health and the Environment • .The selected remedy will provide suitable protection of human health and the environment by implementing institutional controls to prevent disturbance of the surface soils and landfilled materials and by monitoring the ground water to ensure that contaminants that may be released from the former landfill can be detected, contained, and treated to protect the ground water users downgradient of the Landfill site. 2. Compliance with Applicable or Relevant and Appropriate Requirements .. The Applicable or Relevant and Appropriate Requirements (ARARs) are defined as clean-up standards, standards of control, or other environmental protection standards that are used to address problems or situations at a contaminated site. ARARs are classified within three categories: 1) Chemical Specific Requirements - health or risk .based numerical values, which represent an acceptable concentration in the media of concern in the absence of consideration of site-specific exposure conditions; 2) Location-Specific Requirements - limitations on allowable concentrations of hazardous substances due to impacts in special loca'tions, such as critical habitats; and 3) Performance, Design, or Other Action-Specific Requirements - technology based requirements or limitations or actions taken with respect to hazardous wastes. 18 ------- The criteria that will be used in the monitoring of the ground water to determine if ,the contingency of treatment will be implemented are as follows: Maximum Contaminant Levels (MCLs) as promulgated under the Safe Drinking Water Act are the relevant and appropriate standards for remediation of contaminated groundwater. For compounds without a MCL, proposed MCL or state ground water standard, a risk based cleanup level corresponding to an excess lifetime cancer risk of 1 x 10(-6) will be calculated using slope factors for carcinogens (Chemical-Specific). If the monitoring indicates releases of contaminants above the criteria listed above the contingency for the evaluation of appropriate responses for the containment and treatment of the ground water to meet-the following ARARs will be implemented: Effluent limitation guidelines as governed by the Clean Water Act through the National Pollutant Discharge Elimination System (NPDES) are ARARs for any discharge resulting from site remediation, such as pump and treat (Chemical-Specific). There were no location or action specific ARARs. 3. Cost Effectiveness The selected remedy provides a higher degree of overall' protection than the no action alternative by monitoring for any ground water contamination and providing for containing and treating contaminated ground water, thus preventing the migration of contaminated ground water from the area. 4. Utilization of Permanent Solutions and Alternative Treatment Technologies or Resource Recovery Technologies to the Maximum Extent Practicable. EPA has determined that the selected remedy represents the maximum extent to which permanent solutions and treatment technologies can be utilized in a cost effective manner for the site. Of the alternative that is protective of human health and the environment and comply with applicable standards, EPA has determined that this selected remedy provides the best balance of trade-offs in terms of long-term effectiveness and permanence, reduction in toxicity, mobility, or volume achieved through treatment (if needed), short-term effectiveness, implementability, cost, and considering State and community input. 5. Preference for Treatment as a Principal Element If needed the contingency for ground water treatment satisfies the statutory preference for remedies that employ treatment of the principal threat which permanently and significantly reduces the 19 ------- toxicity, mobility, or volume of hazardous substances as a principal element. 20 ------- 8.0 RESPONSIVENESS SUMMARY 8.1 In the proposed plan released for public comment, EPA and KDHE presented a preferred alternative which set forth the proposed final remedy for the institutional controls and ground water monitoring with a contingency for further action at the Obee Road Landfill Subsite. After receiving public comments on the preferred alternative, EPA has selected the alternative set forth in this Record of Decision (ROD). 8.2 Summary of comments and 'questions received during the Public Comment Period. Comments received during the public comment period from March 4,. 1994 through April 2, 1994 are summarized, below with the EPA/KDHE response for each. Attachment II contains the comment letters received in addition to a response letter from KDHE to one of the commentors. A. A comment letter was received from Mr. Dennis Clennan, Director of Public Works & Engineering, City of Hutchinson concerning the stated figures of number of homes and residents located south of the.landfill in Section 2, Paragraph 2.1 of the Proposed Plan. He stated that, based on a March 24, 1994 population study, there are 102 households and approximately 280 people in the area south of the landfill. ~ EPA Response: The correction was made in Section 1.0, Paragraph 1.1 of the ROD. B. Letters were received from two residents that live east/southeast of the Landfill who feel that contamination from the landfill has reached their private ground water wells and that these residents will continue to have water quality problems. One letter also contained a series of questions about the nature of the contamination and the potential effect of the contamination on humans and wildlife in the area. Neither letter suggested any changes to the remedy proposed in the ROD. EPA Response: KDHE responded to the series of questions with a letter which is included with this ROD as Attachment II. EPA agrees with the responses contained in KDHE's letter and incorporates those responses by reference into this responsiveness summary. In response to the concerns expressed in both letters about water quality, EPA acknowledges that residents near the landfill area may have had water quality problems in the past that may have been caused all or in part by contamination from the Landfill. However, at the time 21 ------- that the Remedial Investigation was completed, there was no indication . of any continuing releases from the Landfill. Based on this data, EPA and KDHE believe that the plume of contamination has moved away from the landfill area and has been subjected to natural flushing and dilution within the aquifer. The periodic monitoring of wells required in this ROD is designed to monitor the ground water so that any future release that may occur will be detected and a response action can be taken. In addition, a sampling plan for a number of private ground water wells owned by residents who are not hooked up to the Rural Water District System is currently being developed by the Reno County Department of Health and KDHE in order to ensure that no contamination remains in the area. If contamination of those private ground water wells sampled is detected, then an appropriate action will be determined by KDHE and EPA. 22 ------- ATTACHMENT I Glossary of Terms ARARS - Applicable Relevant and Appropriate Requirements - Clean up standards of control or other environmental protection requirements. AR File - Administrative Record File - includes all pertinent documents and site information which forms the basis for selection of a remedial alternative. CERCLA EPA - FFS - KAL - KDHE - MCL - NPDES - NCP - NPL - PRP - Comprehensive Environmental Response, Compensation and Liability Act of 1980. The federal "Superfund" law. United States Environmental Protection Agency - The support government agency for the Obee Road Landfill Subsite. Focused Feasibility Study. The study used to evaluate various alternatives to address potential risks to health and environment. Kansas Action Level is a concentration that could produce chronic health effects after long term consumption of water. If a contaminant is detected at or above the KAL in a public water supply, the well must not be used for drinking water purposes. Kansas Department of Health and Environment. government agency for the Site. Maximum Contaminant Level - The maximum contaminant allowed in ground water by EPA. The lead amount of National Pollutant Discharge Elimination System - a permit that sets standards for the discharge of potentially contaminated ground water. National Oil and Hazardous Substances Pollution Contingency Plan. The procedures used to address the response powers and responsibilities created by the federal Superfund law. National Priorities List. A list of most contaminated sites as determined by the NCP. Potentially Responsible Party - The party (or parties) identified by EPA which is potentially responsible for contamination. 23 ------- RCRA - Resource Conservation 'Recovery Act. RI - The process which identifies site conditions, extent of contamination, and site risks. ROD - Record of Decision - The official document by EPA which selects the remedy to clean up a Superfund site. SARA - Superfund Amendments and Reauthorization Act of 1986. The federal law which amended and extended authorization of the original Superfund law (CERCLA). SVOC - Semi-Volatile Organic Compound. VOC - Volatile Organic Compound. 24 ------- ATTACHMENT II 25 ------- POST OFFICE BOX 1567: 67504-1567 TELEPHONE (316) 694-2644 FAX (316)694-2673 OFFICE OF: D- CLENNAN RECEIVED March 25, 1994 SPED Ms. Rachel Miller KANSAS DEPARTMENT of HEALTH and ENVIRONMENT Forbes Field, Building 740 Topeka, Kansas 66620-7500 Reference: Obee Road Subsfte Dear Rachel: I would like to offer a comment on the Proposed Plan for the Obee Road Landfill Subsite. In Section 2, paragraph 2.1, you state that there are 500 homes and 1900 residents located south of the landfill. I believe your figures are in error. I am enclosing a copy of a memorandum to me from our Associate City Planner which states there are 102 households and approximately 280. people. i for your attention to this detail. Sincerely, CITY OF HUTCHINSON Dennis M. Clennan, P.E. DIRECTOR OF PUBLIC WORKS & ENGINEERING DMC/rh Enclosure:as noted PRINTED WITH] SOYINKI ------- PLANNING AND DEVELOPMENT DEPARTMENT 125 EAST AVENUE B; P. 0. BOX 1567 HUTCHINSON, KS 67604-1567 (316) 694-2639 DATE: March 24, 1994 TO: Dennis Clennan, Director of Public Works and Engineering FROM: • T1m Truesdale, Associate City Planner SUBJECT: Obee Road Population Study Area of Interest: the following five quarter sections in Clay Township: 1) S/N 11, 2) N/W 14, 3) S/W 14, 4) N/E 15, 5) S/E 15. Background: A previous study indicated that this area contains 500 households and 1900 people. This number seemed high. Clay Township: The entire township of approximately 34 sections contains 2878 persons in 1047 households. Rough estimate of households in study area: 102 households Rough estimate of persons in study area: 280 persons. Method—Taking the Official 1990 Rural Directory, pencilling off the affected quarter sections, counting the number of households, and multiplying by the 2_.75 persons/household found in Clay Township. Another method would be to use Census data at the block level. At this point, we can't find this data anywhere in Reno County. It was ordered today, and should be available within the next ten days. I will refigure when this data is available. In general, the census method tends to be more accurate. ------- RECEIVED 4PR1 4 |994 Apri I 2. 1994 DearRacnel. ENVfRONAMENTAL APR REMEDIATION Hrn My name is Victor L Wilkinson, my address is 5011 Frank Road SFf-D which is .5 mile south of Obee school and .25 mile east on Frank Road. I have several questions I would like answered about the contaimination in the Obeeville area. I. Is the EPA and KDHE onlv interested in contaimination that is . a carcinogen? 2. Are the test well deoths comparable to residential well depths? Z. I know a person who was raised in the house across the road from me during the 1950s, he said the water was not rusty or odoriferous then. A. Is the dump the source of the excessive rust present in the well water? • B. Is the dump the source of the odor associated with the well water? 4 My two dogs drink some pretty disgusting water wh.en on hunting trips, but they often refuse to drink the well water from their water bowl. Also, after filling their bowls with water, the surface appears to have an iredescent film floating on it similar to gasoline on water. Is this film dangerous to animate or humans, and what is it? c I have noticed foliar damage, stunted growth, and anemia to certain plants and trees from watering with the well water. A. Are there chemicals present in the ground water contaimination that are causing this? B. Are these chemicals making the soil more alkali, and how is it corrected? C. Are the homeowners expected to carry the burden of cost to correct their damaaed soil? ------- 6. The water quality varies (color, rust, odor) from house to house within my neighborhood. Often, the poor water quality seems to be damaging appliances of those who's homes are hooked up to well water. A. Does the ground water take different paths, travel at different rates, and" possibly pool up and stagnate underground? B. If a homeowner feels his water is damaging his landscaping, water related appliances, clothes, or threatening the health of family members can his water be checked by the EPA/KHDE at no cost? C. Is the cost of appliance replacement, clothing replacement, water damaging property figured in the in the clean up costs? Can the residents expect any reimbursement from the PRPs? 7 A. I fish in a sandpit in the area that has depths to 50 feet, will the larger.and older fish in this-water accumulate ... • -^ contaiminates in their tissues over the years? B. Have any of these larger fish been tested? C. Will bottom feeding fish (catfish, carp, etc.) be affected more than preaators (largemouth. crappie. flat heads)? D. Will federally protected fish eating birds such as ospreys. bald eagles, canvasbacks, etc., that feed on the sand pit during seasonal migrations be affected? How about resident fish eating birds? Thank you so much for answering my questions. Victor L Wilkinson P.S. Any person who doesn't believe the ground water is contaiminated is welcome to come to my house for fresh glass of well water. ------- State of Ka nsas Joan Finney, Governor Reply To: (913) 296-1673/ PAX (913) 296-1686 Bureau of Envinnm Fofbet Field. Biddi* 740 Topdu, KS 6662M001 Department of Health and Environment Robert C. Harder, Secretary May 23, 1994 Victor L. Wilkinson 5011 Frank Road Hutchinson, Kansas RE: Obeeville area Dear Mr. Wilkinson: This letter responds to your letter of April 2, 1994, containing questions regarding environmental concerns in the Obeeville area. We are providing responses to your questions in the following paragraphs. Question 1. Is the EPA and KDHE only interested in contamination that is a carcinogen? Response. In the interest of protecting human health and the environment, EPA and KDHE are concerned with any contaminants which are known _to be a- possible threat to. humanvi^al;th;..and.v^e environment. These contaminants would include both"'carcinogens and noncarcinogens. Question 2. Are the test well depths comparable to residential well depths? Response. The monitoring wells constructed for investigations in the area under KDHE oversight have been constructed in both the upper aquifer zone and the lower aquifer zone. Therefore, the answer to your question is "yes", there would be monitoring wells constructed at depths comparible to residential well depths whether they are screened in the upper zone, the deep zone, or both. Question 3A. Is the dump the source of the excessive rust present in the well .water? Response. There is no evidence which has shown that the landfill is a source of iron in the ground water. Water well and test hole data collected during a Kansas Geological Survey (KGS) study completed in 1956 indicate that high iron concentrations in water in this area are not uncommon in naturally occuring ground water. Landon Stata Offica Bulling. To'peka. 66612-1290 • Forfaas Field. Building 740, Topaka. 66620-0001 • Mill* Building. 109 SW 9th. Topeka, 66612 Printfd on Rtcyeted A>per ------- Mr. Victor L. Wilkinson May 23, 1994 Page 2 Question 3B. Is the dump the source of odor associated with the well water? Response. Since contamination in ground water due to the landfill was shown to be very limited and non-detectable outside the landfill area, it is unlikely that the landfill is a source of odor in the veil water in your residential area. There are -many possible causes of odor from well water which might be attributable to the structural condition of the well and/or the natural ground water chemistry. The water should be tested to determine the possible source of the objectionable odor. Question 4. Is this film (irredescent film floating on well water) dangerous to animals or humans, and what is it? Response. The well water should be tested to determine the cause of this "film". Hardness in water, a high dissolved solids content, and a high iron content, can often cause a film to be present on water. Question 5A. Are there chemicals present in the .ground water contamination that are causing this (foliar damage, stunted growth, to certain plants and trees from watering with the well Response. The well water should be tested to determine whether there are chemicals which might cause damage to vegetation. Question 5B. Are these chemicals making the soil more alkali, and how is it corrected? Response. The well water should be tested to determine whether there are chemicals which might cause the soil to become more alkali. Water which is hard is generally associated with high alkalinity. Question 5C. Are the homeowners expected to carry the burden of cost to correct their damaged soil? Response. Again, the well water should be tested to determine whether there are chemicals present which might cause the soil to become damaged. A determination should be made as to whether the chemicals are attributable to the natural ground water or to a specific source of contamination. Question 6A. Does the ground water take different paths, travel at different rates, and possibly pool up and stagnate underground? ------- Mr. Victor L. Wilkinson May 23, 1994 Page 3 Response. The ground water flow direction and rate of flow is relatively uniform throughout the Obeeville area. This type of flow is not characteristic of stagnant conditions. See the attached map showing the ground water flow direction in the area. Question 6B. If a homeowner feels his water is damaging his landscaping, water related appliances, clothes, or threatening the health of family members, can his water be checked by the EPA/KDHE at no cost? Response. KDHE will sample and analyze your well water for volatile organic compounds (VOCs) to determine if any' of these contaminants are present in your water. VOCs are not naturally occuring constituents found in ground water. However, the well owner is responsible for the testing of well water for potentially naturally occuring chemicals. This would include testing for hardness, iron, other inorganic constituents, and bacteria. We have enclosed information concerning laboratories available to test your water for inorganics and bacteria. KDHE and EPA, in cooperation with the Reno County Health Department, will be performing, sampling of residential wells in your area for VOCs within the next few months. We will contact you to set up a time to sample your well. Question 6C. Is the cost of appliance replacement, clothing replacement, water damaging property figured in the clean up costs? Can the residents expect any reimbursement from the PRPs? Response. Again, the water should be tested and a determination should be made as to whether chemicals found in the ground water are the cause of the above cited damages. If these chemicals are determined to be the cause of such damages, then a .determination should be made as to whether or not they are naturally occuring. Clean up costs do not generally include personal damages such as those cited above. If reliable evidence can be shown to indicate a specific PRP is responsible for a resident's contamination problem, the resident may seek reimbursement from the PRP. Question 7A. Will the larger and older fish in this water accumulate contaminants in their tissues over the years. Response. Sampling of water and sediment in a sand pit in a nearby area of contaminated ground water did not indicate the presence.of VOC contamination. Therefore, we would not expect contamination to be present in fish in these waters. ------- Mr. Victor L. Wilkinson May 23, 1994 Page 4 Question 7B. Have any of these larger fish been tested? Response. No, since no contamination in surface water or sand pit sediment was found, fish were not tested. Question 7C. Will bottom feeding fish (catfish, carp, ect.) be affected more than predators (largemouth, crappie, flat heads)? Response. Thus far, there is no indication that any fish will be affected by VOC contamination in the ground water. Question 7D. Will federally protected fish- eating birds such as ospreys, bald eagles, canvasbacks, etc., that feed on the sand pit during seasonal migrations be affected? How about resident fish- eating birds? Response. There is no indication that contamination is present in sand pit sediment, surface water, or fish in the area. I hope your questions have been adequately addressed and encourage you to contact me at 913-296-1676 if you have further questions or concerns. You may wish to contact Helen Tinson at 913-551-7343 of the EPA Office of Public Affairs to inquire into your ability to obtain a Technical Assistance Grant (TAG) for the purpose of performing your own investigation into some of these problems which might relate to the Obee Road Superfund Site. Sincerely, Rachel Miller Environmental Geologist . Remedial Section/Superfund Unit Bureau of Environmental Remediation RM/jdh Rick Bean—>file Kyle Parker - SCDO Ken Rapplean - EPA Helen Tinson - EPA Judy Seltzer - Reno County Health Dept. ------- f line. £.nv Kerneo lat ion PosHf brand fax transmmoi m»mo 7671 INO &/*> f57- flpr 7,94 15=29 No.009 P.01 DECEIVED _ OUKSAU or ENVIRONMENTAL REMEDIATION o I ------- KDHE Env Remediation TEL No. 913-296- 1686 Rpr 7 , 94 15 =29 No . 009 P. 02 0W .*- s&p. ------- 78 FIGURE 1 OBEE ROAD LANDFILL SUBSITE LOCATION MAP ------- OBEE ROAD LANDFILL SUBSITE LEGEND NOTE. AJRPORT PROPERTY BOUNDARY BOUNDARIES SHOWN ON THIS FIGURE ARE APPROXIMATE. INFORMATION TAKEN FROM THE RENO COUNTY ZONING MAP AND THE HUTCHINSON MUNICIPAL AIRPORT LAND USE MAP RESIDENTIAL :NDUSTRIAL AGRICULTURAL [~£J SCHOOL FIGURE 2 OBEE ROAD SITE AREA AND LAND USE MAP SOURCE: Remedial Investigation Report Obee Road Subsite; November 1993 ------- Obee Road Supertund Site Boundary ! \ ^ •» OBEE ROAD MONITORING WELLS X • KOHE MONITORING WELLS A OBEE ROAD PIEZOMETERS A AIRPORT BORINGS • WATER-TABLE BORING ° LANDFILL BORINGS SHALLOW SOIL SAMPLING AREA i !> ( A I f IN I I | 1 SOURCE: Remedial Investigation Report Obee Road Subsite; November 1993 FIGURE 3 MONITORING WELL LOCATIONS IN OBEE ROAD SITE AREA ------- APPROXIMATE LANDFILL BOUNDARY UTCHINSON AIPOR SO A LB-3E Obeeville SOILBORINGS ) CONCENTRATION OF TETRACHLOROETHENE • 110J«fltsaiS(2-ETHYLHEXYL)PHTHALATE JT 1 200 X*w*sAROCLOR- 1254 (N.S) NOT SAMPLED Notes: J - Estimated value less than contract required quamitation limit. X - Value was manually calculated! 500 1000 _ SCALE IN FEET SOURCE: Remedial Investigation Report Obee Road Subsite; November FIGURE 4 ANALYTICAL RESULTS OP SOIL SAMPLES FROM LANDFILL ------- NOTES: / / 1. MONITORING WELLS SAMPLEw MAY 1992 EXCEPT WHERE INDICATED. 2. WATER TABLE BORINGS SAMPLED SEPTEMBER 1991. 3. SEE APPENDIX FOR / EXPLANATION OF DATA QUALIFIERS. / / APPROXIMATE LANDFILL BOUNDARY Maihylene 1J ug/L Chloride Vinyl 2J ug/l Chloride Obeeville 4THAVENUE 75/2 WT-4 • KDHE MONITORING WELi ® NEW MONITORING WELL ©WATER TABLE BORING soo o 1000 S C A L = IN .= = = T SOURCE: Remedial Investigation Report Obee Road Subsite; November 19£ FIGURE 5 vocs IN GROUND ------- TABLE 1 XDHE MONITORING WELL RESULTS OBEE ROAD SITE HW-1 MW-2A MW-2B HH-3 MW-4 HW-5 MW-6 MH-7 YEAR SAMPLED 1984 1985 1986 1990 *1991 **1991 1984 1985 1986 1990' *1991 **1991 1984 1985 1986 1990 *1991 1984 1985 1986 . *1991 **1991 1984 1985 *1991 1984 1985 1986 *1991 **1991 1984 198.5. •1986 *1991 **1991 1984 1985 1986 *1991 TOTAL VOC3 (uafl) 1660 5024 9290 193.2 124 166.5 17 22.5 9.7 59.1 25 38.5 10 9.8 10.5 59.1 44 19.1 25.3 17.7 ND ND 24.4 7 ND 16.1 109.4 7.7 ND 1.9 16.8 22.9 17.1 9 ND ND ND ND 5 SUBSITE AREA Airport Road Airport Road Airport Road Landfill Landfill Landfill Landfill Landfill ND - Not Detected * - Samples collected during Phase I Remedial Investigation (2/26/91); Burns & McDonnell sample ** - Samples collected during Phase I Remedial Investigation (2/26/91); KDHE split sample All other samples were collected by KDHE ------- TABLE 2 ESTIMATED COSTS FOR THE PREFERRED ALTERNATIVE SOURCE: Focused Feasibility Study Report Obee Road Subsite; January 1994 Item . • . 1. Groundvacer Monitoring Analytical $ 4,000 Field Labor 5,000 Expenses 3,000 Report Preparation • 6.000 Total Item 1 Estimated Annual Cost $18,000 Total Item 1 Estimated Present Vorth Cost* $ 82,440 2. Fence Maintenance Labor $ 500 Materials 500 Total Item 2 Estimated Anr.uai Ccst ' $ 1,000 Total Item 2 Estimated Present «orth Cost" $ 4,580 3. Deed Restrictions Lump sum for costs associated vith attorney fees, city review, and filing with County Records Office • $ 1, OOP Total Item 3 Estimated Cost 1,000 Total Item 3 Estimated Present Vorth Cost $ 1,000 4. Subtotal . $ 88,020 5. Contineencv (15 percent^ $ 13.203 'ALTERNATIVE 2 ESTIMATED TOTAL PRESENT WORTH COST $101,223 USE: $100,000 Present worth cost is calculated for a 5-year period at a 3 percent net interest rate (6 percent interest rate less 3 percent inflation) with the present worth factor = 4.580. ------- |