United States Office of Environmental Protection Emergency and Agency Remedial Response EPA/ROD/R05-93/240 March 1993 f/EPA Superfund Record of Decision: Muskegon Chemical, Ml ------- 50272.101 REPORT DOCUMENTATION 11. REPORT NO. 2. 3. Rec:ipient'. Acce8.lon No. PAGE EPA/ROD/R05-93/240 4. Thl. and Subtitle 5. Report Date SUPERFUND RECORD OF DECISION 03/10/93 Muskegon Chemical, MI 6. First Remedial Action 7. Author(a) 8. Parformlng Organization Rept. No. 9. Performing Organization Name and Addr- 10 ProJact Ta8k/Work Unit No. 11. Contrect(C) or Grent(G) No. (C) (G) 12. Sponsoring Organization Name and Add,... 13. Type of Report & Period Cov.red U.S. Environmental Protection Agency 401 M Street, S.W. 800/800 Washington, D.C. 20460 14. 15. Supplomentary Note. PB94-964110 16. Abstrect (Limit: 200 words) The Muskegon Chemical site is located in Whitehall and Fruitland Township, Muskegon County, Michigan. The site consists of a 19.6-acre chemical manufacturing plant; the downgradient area between the plant and Mill Pond Creek; and a surface water body located approximately one-half mile southwest of the plant. Land use in the area is. predominantly ~ight industrial and residential, with wooded areas to the east of. the plant and a narrow marshy area adjacent to Mill pond Creek. Underlying the site are two glacial drift aquifers, which are used by area residents as a drinking water source. A municipal water supply well is located 900 feet north of the fa cHi ty; however, ground water flow in the area is to the south-southwest towards Mill Pond Creek. The nearest residential well downgradient of the plant is one-half mile to the south-southwest. In 1975, the Muskegon Chemical Company began production of specialty chemicals at the plant. In 1977, ground water contamination was first detected during testing for installation of an industriai water supply well at the facility. In 1980, an investigation indicated the presence of several VOCs in ground water and documented that the plume was 1,150 feet in length and flowed in a southwesterly direction. In 1981, the State discovered that the ground water contaminant plume was discharging to (See Attached page) 17. Document Analysis .. Descriptors Record of Decision - Muskegon Chemical, MI First Remedial Action Contaminated Medium: gw Key Contaminants: VOCs (PCE) b. IdantlfilnslOpen-EncI8d Ttnn8 c. COSATI Fielci'Group 18. Availability Stat_nt 19. Security Class (thIs Report) 21. No.ofPag.. None 34 20. Security Class (this Page) 22. Price None (See ANSI.Z39.18) s..lnstructions on Reverss OPTIONAL FORM 272 (4-77) (Formerly NTlSo35) Department of Commerce ------- EPA/ROD/R05-93/240 Muskegon Chemical, MI First Remedial Action Abstract (Continued) Mill Pond Creek. The State determined that this discharge is a threat to human health and the environment. In 1981 and 1983, the State required additional ground water investigations and installation of ground water purge wells and a ground water treatment system. In 1985, Koch Chemical Company purchased the facility from Muskegon Chemical. In 1986, the State ordered Muskegon Chemical and Koch to continue operation of the existing purge well system for seven years. In 1989, after a State report indicated that contaminants still were impacting Mill Pond Creek, additional investigations were conducted to document the level of contamination at the Muskegon facility. In 1991, the State required Koch to conduct an interim response action and additional site investigations. This ROD documents the details of the interim response action which addresses the contaminated offsite ground water discharging into Mill Pond Creek. A future ROD will address onsite soil and ground water contamination. The primary contaminants of concern affecting the ground water are VOCs, including PCE. The selected remedial action for this site includes installing as many 4-inch diameter purge wells as are needed to capture the contaminated ground water plume and prevent further discharge to Mill Pond Creek; extracting and treating contaminated ground water onsite using Koch's granular activated carbon treatment system to remove organics; discharging the treated water offsite to the Whitehall area POTW; sampling soil and ground water in the Mill Pond Creek's floodplain during or prior to well installation; and monitoring soil, ground water, surface water, and air to determine effectiveness of the treatment system. The estimated present worth cost for this remedial action is $540,000, which includes an estimated annual O&M cost of $330,000 for one year. PERFORMANCE STANDARDS OR GOALS: Chemical-specific soil and sediment cleanup goals are ba~edon the State risk-based cleanup criteria,-and include aluminum 1 mg/kg; arsenic 0.0004 mg/kg; barium 40 mg/kg; bis(2-ethylhexyl)phthalate 40mg/kg; cadmium 0.08 mg/kg; chromium 2 mg/kg; 4,4-DDE 2 ug/kg; 4,4-DDD 2 ug/kg; dieldrin 0.04 ug/kg; di-n-octylphthalate 2,000 ug/kg; lead 0.08 mg/kg; mercury 0.04 mg/kg; nickel 2 mg/kg; and PCE 14 ug/kg. Chemical-specific ground water cleanup goals also are based on the State risk-based cleanup criteria, and include alpha-chlordane 0.03 ug/l; arsenic 0.02 ug/l;' beta-SHC 0.02 ug/l; boron 600 ug/l; chrysene 0.003 ug/l; dieldrin 0.002 ug/l; gamma-chlordane 0.03 ug/l; lead 4 ug/l; PCE 0.7 ug/l; sodium 150,000 ug/l; 1,1,2,2-TCA 0.2 ug/l; and TCE 3 ug/l. However, if site background concentrations exceed these values, then the site background level shall replace a risk- based cleanup criterion. ------- .,' DECLARATION FOR THE RECORD OF DECISION Site Name and Location Muskegon Chemical Company 1725 Warner Street Whitehall, Muskegon County, Michigan Statement of Basis and Purpose This decision document presents the selected interim response action for the Muskegon Chemical Company Site in the city of Whitehall and Fruitland Township, Muskegon County, Michigan (see figure 1). This interim response action was chosen in accordance with the requirements of the Michigan Environmental Response Act, 1982 PA 307, as amended; the Comprehensive Environmental Response, Compensat i on and L i abil ity Act of 1980 (CERCLA) as amended by the Superfund Amendments and Reauthorization Act of 1986 (SARA); and the National Oil and Hazardous Substances Pollution Contingency Plan (NCP). The decisions contained herein are based on the information contained in the administrative record for this site. The U. S. Envi ronmenta 1 Protection Agency (EPA) has chosen not to revi ew the . selection of this interim action at this time. " Assessment of the Site Actual or threatened releases of hazardous substances from this site, if not addressed by implementing the response action selected in this Record of Decision (ROD), may present an imminent and substantial endangerment to public hea1th, welfare or the environment. Description of the Selected Remedy This interim response action addresses the contaminated groundwater plume in the vicinity of Mill Pond Creek. The Engineering Evaluation and Cost Analysis Report for the Muskegon Chemical Company site identified the area where contaminated groundwater discharges to the surface waters of Mill Pond Creek as an area of concern. The i nteri m response action chosen for the Muskegon Chemi ca 1 Company site, described in the attached Decision Summary, will reduce the potential for human exposure to hazardous substances from contact with contaminated surface water. The principal threats will be mitigated by a groundwater extraction and treatment system. The interim response action will be closely monitored throughout implementation and should monitoring indicate the ineffectiveness of any component of the remedy, corrective action will be taken. The major components of the interim response action selected to address this area of concern include the following: * extraction of groundwater to capture and halt the flow of the contaminated groundwater plume before it reaches Mill Pond Creek, ------- * removal of organic contaminants by carbon adsorption, * discharge of treated water to the Whitehall Area Publicly Owned Treatment Works (POTW), and * surface water, groundwater, soil and air monitori ng to' be conducted to assess the effectiveness of the system at halting the migration of contamination and reducing the levels of contamination in the groundwater, surface water and air. . Statutory Determinations The selected i nteri m response act ion is protect i ve of human health and the environment, complies with federal and state requirements that are legally applicable or relevant and appropriate for this interim response action, and is . cost-effective. Although this interim response action is not intended to fully address the statutory mandate for permanence and treatment to the maximum extent practicable, this interim response action utilizes treatment that reduces toxicity, mobility or volume as the principal element and thus is in furtherance of the statutory mandate. Subsequent actions are planned to fully address the threats posed by the conditions at this site. Russell arding Deputy irector Michigan Department 7ao)r ~ Date -2- ------- DECISION SUMMARY FOR THE RECORD OF DECISION Site Name. Location. and Description The Muskegon Chemi ca 1 Company site is located in the city of Wh i teha 11 and Fruitland Township, Muskegon County, Michigan (see figure 1). The site consists of the former 19.6 acre Koch Chemical Company's Whitehall Specialty Chemical Plant located at 1725 Warner Street, and extends approximately! mile southwest to Mi~l Pond Creek. The area of concern for the interim response action is the area bounded by Mill Pond Creek to the south and west Simonelli Road to the east, and White Lake Drive to the north (see figure 2). The former Koch Chemical Company facility is bordered on the north by a light industrial area, an open wooded area to the east, the C&O Railroad to the south, and Warner Street to the West. Another light/medium industrial area (Howmet/MISCO Corporation) is located on the west side of Warner Street, across from the facility. South of the railroad tracks is a wooded area drained by Mill Pond Creek. A narrow marshy area is located adjacent to Mill Pond Creek throughout the interim response action area of concern. Investigations have shown that two glacial drift aquifers are present beneath the Muskegon Chemical Company site which are separated by a silt and clay confining layer. These are in turn underlain by a thick layer of clay that forms the base of the aquifer in this area. The direction of groundwater flow in the area of concern is to the south - southwest towards Mill Pond Creek. Information obtained from the interim response action and remedial investigation studies indicate that groundwater in the upper sand aquifer discharges to Mill Pond Creek. Many residences in this area use both the upper and lower aquifers as a SQurce of drinking water. Sampling of residential wells in the vicinity of the site in June 1991, did not show any impact from the contaminated groundwater plume. The nearest residential groundwater wells are located t mile north and ~ mile south southwest of the site. A Whitehall municipal well is located 900 feet north of the facility. . Site History and Enforcement Activities The Muskegon Chemical Company began production of specialty chemicals at the Whitehall facility in.1975. Groundwater contamination was initially discovered in 1977, during testing for the installation of an industrial water supply well at the facility. A hydrogeologic investigation conducted in 1980, identified three primary organic contaminants of concern in the groundwater: 1,2 dichloroethane (DCA), bis (2-chloroethyl) ether (Chlorex), and triglycol dichloride (TGDC). The contaminant plume was estimated to be 1,150 feet in length, flowing in a southwesterly direction from the facility. The Muskegon Chemical Company installed one purge well, centrally, in the path of the plume. The probable ------- source of contamination was identified as a leak in the drainage system inside the Muskegon Chemical Company manufacturing facility, which was subsequently repaired. In 1981, it was discovered that the groundwater contamination plume from the Whitehall facility was discharging to Mill Pond Creek. As a result of this discharge, the Michigan Department of Natural Resources (MDNR) and the Muskegon Chemical Company entered into a consent agreement and a plea agreement in 1981 and 1983 respectively. These agreements required the Muskegon Chemical Company to conduct two hydrogeologic investigations, and to install several groundwater purge wells and a groundwater treatment system. On December 31, 1985, Koch .Chemica1 Company (Koch) purchased the Whitehall facility from Muskegon Chemical Company. On January 7, 1986, Muskegon Chemical Company, Koch, and the MDNR entered a consent agreement wh i ch approved the existing purge well system and established a seven year period of operation. A March 1989, report by the Surface Water Quality division of the MDNR documented continued impact by the Whitehall facility groundwater contamination plume on Mill Pond Creek. On February 21, 1990, the Muskegon Chemical Company Superfund Site was placed on the National Priorities List (NPL), requiring that contamination at the site be investigated and cleaned up according to the provisions of the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA). On February 25, 1991, Koch and the MDNR signed an Administrative Order by Consent, that requires Koch to conduct an interim response action and a Remedial Investigation and Feasibility Study (RIfFS) under direction of the MDNR. As a result of this order, Koch has retained the firm of CH2M Hill to perform the interim response action and RIfFS. During the summer of 1991, Koch conducted field activities, which included ground water, surface water, soil and sediment sampling, as part of the interim response action and remedial investigation at the site. Hiqh1iqhts of Community Participation A chronology of community relation activities for the Muskegon Chemical Company site is provi ded as part of the attached Responsi veness Sumary. The Engi neeri ng Evaluation and Cost Analysis (EEjCA) report and interim response action Proposed Plan for the Muskegon Chemical Company site were released for comment on April 14, 1992. These two ~ocuments were made available to the public in both the administrative record and the information repository maintained at the Whitehall City Library and the MDNR, Environmental Response Division, Superfund Section office in Lansing, Michigan. The notices of availability for the EE/CA report and Proposed Plan were published in the White lake Beacon and the Muskegon Chronicle. Issuance of the Proposed Plan detailing the MDNR's preferred alternative, on April 14, 1992, initiated a 30 day public comment period for both the Proposed P1 an and the EE/CA report. A pub 1 i c meeting' and avail abil i ty session was held on April 30, 1992, at the Whitehall City Hall. Themeeting consisted of a short presentation outlining the results of the field 4 ------- investigation and the alternatives considered for the interim response action, followed by a formal question and answer session. Following the public meeting, the MDNR project manager and representatives from the Koch Chemical Company were available for informal discussion on the EE/CA report, the proposed plan, and any other subject related to the Muskegon Chemical Company site. Responses to the comments received during the public comment period are included in the Responsiveness Summary, which is part of this ROD. Scope and Role of Response Action Within Site Strategy The MDNR considers the discharge of contaminated groundwater to Hill Pond Creek to be a threat or potential threat to human health and the envi ronment. Reduction of.this threat or potential threat is best achieved by halting the flow of contaminated groundwater into Mill Pond Creek. The primary human exposure pathway is via direct contact with or incidental ingestion of contaminated surface water. This interim action is necessary to halt the migration of the contaminated groundwater plume and protect human health and the environment from the above mentioned exposure pathway. It is the intent of this interim response action to quickly stop all groundwater contaminated above Michigan Environmental Response Act, PA 307, as amended, Type B levels from discharging into Mill Pond Creek. To the greatest extent practicable, this interim response action will be consistent with the overall remedial action at the site. The Remedial Investigation and Risk Assessment reports are expected to be released in the late Spring or early Summer of 1993. These reports will address ihe remaining areas of concern at the Muskegon Chemical Company site. Summary of Site Characteristics In March of 1992, the MDNR released the EE/CA report for the interim response action at the Muskegon Chemical Company site. During the investigation, the. area of concern associated with the discharge of contaminants to ~ill Pond Creek was characterized, this included the following. Geoloqy and Hydroqeoloqy The geology in the interim response action study area consists of inter-layered sands, silts and clays. The sandy materials are mostly fine to medium sand, with occasional coarse sand with gravel. Where saturated, the sand forms the uppermost aquifer at the site, which is under water table conditions. The upper sand unit is approximately 60 feet thick and is underlain by a thick layer of clay that forms the base of the aquifer in this area. The upper sand is divided roughly in half by a laterally continuous fine grained unit composed predominately of silt with varying quantities of clay. The unit averages about 5 feet in thickness and forms the base of the uppermost aquifer at the site. Observations during field activities suggest that this thin fine grained unit may be laterally continuous beneath Mill Pond Creek and throughout. the interim response action study area. Underlying this silt/clay unit is another fine to medium grained sand layer about 30 feet thick, which is in turn underlain by a substantial thickness of gray clay 5 ------- having interbedded sand units. The 30-foot thick sand unit was observed to be saturated and constitutes a confined aquifer in the vicinity of Mill Pond Creek. Th~ direction of groundwater flow in the interim response action study area i~ to the south-southwest towards Mill Pond Creek. Information obtained from the field investigations indicate that groundwater in the upper sand aquifer discharges to Mill Pond Creek. Many residences in this area use both the upper and lower aquifers as a source of drinking water. Sampling of residential wells in the vicinity of the site in June 1991, did not show impact from the contaminated groundwater plume. The nearest residential groundwater wells are located t mile north and 4 mile south-southwest of the site. A Whitehall municipal well is located 900 feet north of the facility. . Nature and Extent of Contamination The interim response action investigation included studies for potentially contaminated medi.a in the vicinity of Mill Pond Creek, including soils, groundwater, and surface water and sediments in Mill Pond Creek and the unnamed tri butary that runs southeast of the production facil i ty. Results of the investigation show that the groundwater contamination plume is approximately 1,100 feet wide (see figure 2). The groundwater contaminants of concern are tetrach 1 oroethene (PCE), 1,2 d i ch 1 oroethane (DCA), bi s (2 -ch 1 oroethyl) ether (Chlorex), and triglycol dichloride (TGDC). The range of. contaminant concentrations is listed in Table 1. The extent of soil contamination in the floodplain adjacent to Mill Pond Creek will be fully delineated as part of the design of the interim response action. Soil and groundwater contamination in the vicinity of the former production facility will be addressed as part of the final remedial action for the site. Summary of Site Risks Due to the fact that this is an interim response action being performed early in the cleanup process, the quantitative risk assessment for the site has not been completed. However, the Michigan Department of Public Health in conjunction with the Agency for Toxic Substances and Disease Registry have prepared an Interim Preliminary Public Health Assessment for the site. In thjs document several potential exposure routes have been identified. Human Health Risks The following discussion of the Muskegon Chemical Company site risk describes the general concepts used by the MDNR to determine chemicals of concern, risks posed by these chemicals, and impact on risks by the interim response action. 6 ------- TABLE 1 MUSKEGON CHEMICAL SITE INTERIM RESPONSE ACTION CHEMICALS OF CONCERN COMPOUND MAXIMUM CONCENTRATION (ppb) CLEANUP STANDARDS GROUND- . (ppb) WATER CLEANUP surface water/ TYPE TYPE RULE CRITERIA (ppb) groundwater sediment A B 57 1,2-Dichloroethane 200 5 N/A 1 1 1 Tetrachloroethene 16 2 1 1 1 1 bis(2- 7 5 5 5 5 5 Chloroethyl)ether bis(2- 250 N/D 5 N/A N/A 5 Chloroethoxy)ethane 7 ------- Contaminant Identification As discussed previously, Table 1 contains contaminant concentration summaries for the interim response action area of concern, which were taken from the EEICA report. Contaminant concentrations reported in the EE/CA report include groundwater, surface water, and sediment samples. Exposure Assessment The exposure assessment is part of the Ri sk Assessment. Its purpose is to identify the potential exposure pathways and receptors. Identified pathways and receptors are used in conjunction with assumptions of exposure frequency and duration, to model exposure point concentrations. This assessment has not been completed at this time; however, several potential exposure pathways and receptors were identified as part of the Interim Preliminary Public Health Assessment. A. Pathways The following three media have been identified as primary potential exposure pathways: 1. Groundwater Based on existing hydrogeologic and analytical chemical data, a contaminated groundwater plume exists at the site. The plume starts in the vicinity of the former Koch Chemical Company plant and has mi grated south - southwest to Mi 11 Pond Creek and may potent i ally impact surface water. Potential exposure pathways may include. inhalation of volatilized contaminants during showering or bathing, ingestion of; and dermal absorption of organic compounds through water usage. The nearest residential groundwater wells are located k mile north and t mile south southwest of the site. A Whitehall municipal well is located 900 feet north of the facility. 2. Soils Two soil areas of concern have been tentatively identified at the site, these are: 1) The soil on the former Muskegon Chemi ca 1 facility property which is considered to be a potential source of groundwater contamination; and 2) The soil in the marshy area adjacent to Mill Pond Creek that is potentially affected by the discharge. of contami nated groundwater through spri ngs. Derma 1 contact with, accidental ingestion of, and inhalation of volatile organic contaminants and fugitive dust from surface soil contamination are considered to be potential pathways. 8 ------- The soils in the marshy area adjacent to Mill Pond Creek will be addressed by this interim response action. The soils on the former Muskegon Chemical facility property will be addressed as part of the final remedial action at the site. r 3. Surface Water The surface water and sediments adjacent to the area where contami nated groundwater discharges to Mill Pond Creek have been tentatively identified as an area of concern at the site. Dermal contact with, accidental ingestion of, and inhalation of volatile organic contaminants from surface water and sediments are considered as potential pathways. The risk assessment will establish the relative importance of each of the above mentioned exposure routes. B. Potentially Exposed Populations The major potential exposure route is through exposure to contaminated soils in the vicinity of Mill Pond Creek and contaminated surface water and sediments in the Creek. Analysis of groundwater samples collected during the RI indicate that the groundwater contamination plume has not migrated beyond Mill Pond Creek, and that residential wells belonging to potent i a 1 receptors are currently unaffected by the Muskegon Chemi ca 1 Company groundwater contamination plume. A re~idence located at the intersection of Simonell i road and White Lake Drive is the closest existing potential receptor. C. Exposure Estimates and Assumptions Existing groundwater, soils, surface water, and sediment contamination is currently assessed in relation to Type A, B, and C cleanup criteria specified in Act 307 Rules, which provide for Type A, B, and C cleanup criteria. CERCLA Section 121(d)(2)(A)(ii}, and the NCP provide for the consideration of Act 307 Rules in the establishment of cleanup levels. Type A, B, or C criteria are detailed further on in this ROD. Potential groundwater and surface water contamination from the soils adjacent to Mill Pond Creek area is also currently assessed in relation to cleanup levels derived from Act 307 criteria. For soils, cleanup standards are based on the objective of contaminant reduction in the soil matrix to that level which will not leach contaminants above groundwater cleanup levels (R299.5711(2}). Cleanup of the area soil is based on the same objectives as cleanup of the groundwater. The groundwater and soil cleanup standards chosen for this site are based on Act 307 Rules. Criteria for cOJllplying with the Type A, B, or C cleanups are contained in Act 307 Rules. The substantive provisions, Parts 6 and 7 of the Act 307 Rules, are considered applicable or relevant and appropri ate requi rements (ARARs) for the remedi a 1 action to be 9 ------- undertaken at the Muskegon Chemical Company site. These Rules require that remedial actions shall be protective of public health, safety, and welfare and the environment and natural resources (R299.5601(1». The Act 307 Rules specify that this standard be achieved by a degree of cleanup which conforms to one or more of the Type A, B, or C cleanup criteria. A Type A cleanup generally achieves cleanup to background or non-detectable levels (R299.5707); a Type B meets risk-based cleanup levels in all media (R299.5709, 5711, 5723, and 5725); and Type C cleanup is based on a site- specific risk assessment which considers specified criteria (R299.5717 and 5719). Contaminant levels found in the groundwater exceed the groundwater cleanup criteria, as shown in Table 1. Toxicity Assessment A toxicity assessment, including a discussion of cancer potency factors and reference doses for all contaminants of concern, will be included in the risk assessment report. Risk Characterization Risk characterization including carcinogenic and noncarcinogenic risks and uncerta i nty in the ri sk assessment will be addressed as part of the ri sk assessment report. ' Environmental Risk Over and above its utilitarian value to humans as a usable aquifer as defined by the Water Quality Commission Act Part 22 Rules (R3223.2203(i», the groundwater is a resource to be evaluated as are all other environmental compartments and 1 ife forms. Based on the findings of the Interim Response and Remedial Investigations, a portion of the groundwater and surface water at the Muskegon ~hemical Company site has been degraded and poses the potential for further degrading groundwater, surface water and sediments downgradient, if not remediated. The prevention of further degradation of the presently contaminated groundwater, surface water and sediments is an environmental remedial objective that needs to be addressed by any final remedy chosen for the Muskegon Chemical Company site. Chemicals of Concern and Cleanup levels Chemicals of concern were determined for the interim response action. The basis for the selection of the four chemicals of concern (noted in Table 1) are those detected at levels, in Interim Response and Remedial Investigation sample analysis, which pose a potential risk to human health and the environment. The Chemicals of Concern pose a potential risk by either exceeding the level for the one in a million (lx10-6) carcinogenic risk, or by exceeding a detection limit, where the detection 1 imit is above the concentration which present a 1xlO-6 carcinogenic risk. The basis for the selection of these cleanup levels are 10 ------- provided in the Act 307 Rules (R299.5705, 707, 709, 717), CERCLA Section 121(d}(2}(A}(ii}, and the NCP. <> Three chemi ca 1 s of concern, bi s (2-Chl oroethyl )ether, 1,2 -di chl oroethane and tetrachloroethene, are known to cause cancer in laboratory animals, and are therefore classified as carcinogens. These compounds have 1x10.6 carcinogenic risk levels which are lower than what can be detected by current laboratory methodologies. The cleanup levels for these chemicals of concern are set by their respective method detection limits. Very little toxicological information is available about bis(2-chloroethoxy)- ethane. At this time it is not considered to be a carcinogen. Due to the lack of information the cleanup level has been set equal to the method detection limit for this compound. Contami nant 1 eve 1 s found in the groundwater exceed the groundwater cleanup criteria, as shown in Table 1. Summary of RisKS Potent i a 1 ri sks from di rect dermal contact or from i nha 1 at i on of airborne contaminants in the soils, surface water and sediments in or adjacent to Mill Pond Creek may pose a risk to human health. Although no individuals are directly ingesting contaminated groundwater from the Muskegon Chemical Company site, the contamination discharging to soils, surface water and sediments in or adjacent to Mill Pond Creek could pose a health risk to potential receptors. In order to prevent further degradation of soils, surface water and sediments and to protect public health and the environment, remediation of the groundwater resource is necessary. Actual or threatened releases of hazardous substances from the Muskegon Chemical Company site, if not addressed by implementing the response action selected in this ROD, may present an imminent and substantial endangerment to public health, welfare, or the environment. Alternatives ScreeninQ Process Preliminary Screening A preliminary screening of remedial alternatives was conducted as a first step of the EE/CA report. The preliminary screening first assembled general response actions which satisfy the remedial objectives of the interim response action. The fo 11 owi ng general categori es of response actions were i nc 1 uded in th is preliminary screening process: . * * No Action Groundwater collection In situ treatment Ex situ treatment and discharge * * 11 ------- Four factors were used to screen the preliminary remedial technologies and their associated process options: technical feasibility; effectiveness; environmental impacts; and cost. . . ~ As a resul t of the pre 1 imi nary screeni ng process, only one option for the treatment and discharge of contaminated groundwater met all four of the screening criteria. This is the Collection System Flow Redistribution, Granular Activated Carbon (GAC) Pretreatment and Discharge to Whitehall Area Publicly Owned Treatment Works (POTW). Koch currently has a permit to discharge 150,000 gallons per day of pretreated water to the Whitehall Area POTW. Under this treatment and. discharge alternative, flow from the existing system would be redistributed to allow the volume from the new system to be incorporated within the limits of the existing permit. Contaminated groundwater from the interim response action purge system would be treated in Koch's existing GAC treatment system prior to discharge to the Whitehall Area POTW. . All alternatives discussed below will be implemented using an. "observational approach" . Thi s means that the selected remedy wi 11 be constructed in a step-wise fashion. For example, one purge well would be installed, developed, and pumped to determine the cone of influence, and the location of the next well would be based on the results of the first well. This process would. be repeated until enough wells were installed to capture the entire plume. The use of this observational approach will allow for the most efficient and expeditious installation of the system and will increase the likelihood of implementation during the 1992-1993 construction season. . Detailed Evaluation of Alternatives On 1 y a 1 i mited number of a lternat i ves rema i ned for th is action after the preliminary screening process. The reader is directed to Tables 4~6 through 4-12 (and associated text in Chapter 4) of the EEICA report. The resulting viable remedial action alternatives were secondarily screened, based on the nine criteria outlined below. It was at this stage, prior to the detailed screening, that options were combined to form a range of treatment and disposal alternatives for the interim response action. Description of Alternatives The interim response action alternatives described below, were evaluated in the EE/CA report as Alternatives 1 through 4-B--with Alternative 1 being the No Action Alternative; Alternatives 2 through 48, variations on groundwater extraction and treatment. Alternative 1 - No Action The No Action alternative is included to satisfy the requirements of the National Contingency Plan (NCP) (40 CFR 300.430(e)(5)). Under this alternative, no 12 ------- further remedial measures would be taken for the interim response action, other than those previously implemented at the site. . Capital Cost: $ 0 Annual Operation and Maintenance (O&M): Total Costs wi 1 Year O&M: $ 0 $ 0 The Superfund program requires that the No Action alternative be evaluated at every site to establish a baseline for comparison. Under this alternative, no further action would be taken at the site to prevent potential exposure to contaminants migrating from the groundwater to the surface water. Alternative 2 - Bluff interception wells Under this alternative, 4-inch diameter groundwater purge wells would be installed along the bluff. This system would capture the width of the contaminant plume. Estimated flow of this system is 26 to 52 Gallons Per Minute (gpm) . . The capture zone of thi s system extends to the toe of the bluff, potentially leaving residual contamination in the flood plain to flush to the creek. Capital Cost: $ 210,000 Annual O&M: $ 330,000 Total Costs wi 1 YearO&M: . . $ 540,000 Alternative 2-A - Bluff interception wells, flood plain well points Under this alternative, 4-inch diameter groundwater purge wells would be installed along the bluff. This system would capture the width of the contaminant plume. In addition, ll-inch hand driven well points would be placed the width of the plume in the flood plain to capture any residual contamination that may be present. Estimated flow of this system is 46 to 92 gpm. Capital Cost: $ 230,000 Annual O&M: $ 330,000 Total Costs wi 1 Year O&M: $ 560,000 Alternative 3 - Flood plain interception wells Under this alternative, 4-inch diameter groundwater purge wells would be installed in the flood plain. . This system would capture the width of the contaminant plume. Estimated flow of this system is 25 to 50 gpm. The capture zone of this system extends to the creek. Some draining may occur in the flood plain. Capital Cost: $ 230,000 Annual O&M: $ 330,000 Total Costs wi 1 Year O&M: $ 560,000 13 ------- Alternative 4 - Flood plain interception trench Under this alternative, a four foot wide by six foot deep trench would be dug in the flood plain. This system would capture the width of the plume. The trench would also be lined with a permeable geotextile fabric to prevent erosion. A six inch diameter slotted drain pipe would be placed in the bottom and sump pumps woul d be placed along the trench, as necessary, to collect any water enteri ng the trench. The trench woul d then be backfi 11 ed wi th gravel. The estimated flow of this system is 43 to 86 gpm. The capture zone of this system extends to the creek. Some draining may occur in the flood plain. ~ Capital Cost: $ 540,000 Annual O&M: $ 330,000 Total Costs wi 1 Year O&M: $ 870,000 Alternative 4-A - Flood plain interception trench and barrier Under this alternative, a four by six foot trench would be dug in the flood plain. This system would capture the width of the plume and be lined with a permeable geotextile fabric. The downstream side of the trench would be lined with an impermeable membrane to block flow. A six inch diameter slotted drain pipe would be placed in the bottom and sump pumps would be placed along the trench as necessary to collect any water entering the trench. The trench would then be backfilled with gravel. The estimated flow of this system is 30 to 60 gpm. The capture zone. of this system would end at the down gradient side of the trench, potentially leaving residual contamination between the trench and the creek to flush to the creek. Capital Cost: $ 560,000 Annual O&M: $ 330,000 Total Costs wi 1 Year O&M: $ 890,000 Alternative 4-8 - Flood plain interception trench and delayed barrier Under this alternative, a four foot wide by six foot deep trench would be dug in the flood plain. This system would capture the width of the plume and be lined with a permeable geotexti1e fabric. A six inch diameter slotted drain pipe would be placed in the bottom and sump pumps would be placed along the trench as necessary to collect any water entering the trench. The trench would then be backfilled with gravel. After the system is operated long enough to remove all contaminated groundwater between the trench and the stream, a bentonite slurry wa 11 wou1 d be i nsta 11 ed down gradi ent of the trench to reduce the flow of uncontaminated groundwater into the system. The initial estimated flow of this system is 43 to 86 gpm. The estimated flow after installation of the slurry wall is 30 to 60 gpm. Prior to installation of the slurry wall the capture zone would extend to the creek. After installation of the slurry wall the capture zone would end at the slurry wall. Capital Cost: $ 620,000 Annual O&M: $ 330,000 Total Costs wi 1 Year O&M: $ 950,000 14 ------- The detailed evaluation of alternatives based on the nine criteria is described as below. Detailed Evaluation of Alternatives The following nine criteria, outlined in the NCP at Section 300.430(e}(9}(iii), were used to compare' the a 1 ternat i ves and to determi ne the most appropri ate alternative for remediation of the soils and groundwater that is protective of human health and the environment, attains ARARs, is cost-effective and represents the best balance among the evaluating criteria. The paragraph(s) following each criterion detail how the alternatives meet or fail to meet, that criterion. This comparison of alternatives considers the options for the interim response action. 1. Overall Protection of Human Health and the Environment addresses whether or not a remedy provides adequate protection and describes how risks are eliminated, reduced or controlled through treatment, engineering controls or institutional controls. All of the alternatives considered for the interim response action, with the exception of the No Action alternative, adequately reduce the risk to human health and the environment by limiting the potential for further contaminant migration to the surface water. Alternatives 2 and 4-A could potentially' leave residual contamination in the flood plain to flush to the Mill Pond Creek. All other alternatives would stop the flow of contaminants to the creek. All groundwater options 'woul d stop the majority of the flow of contami nants into Mill Pond Creek, eliminating the direct dermal contact and ingestion of surface water exposure pathways. All of the alternatives, with the exception of the No Action alternative, will remove contaminants to an acceptable level prior to discharge to the Whitehall Area POTW. The water will be further treated at the Whitehall Area POTW through biological degradation before discharge to the environment. Any short term risks associated with the alternatives are primarily due to construction activities. A health and safety program will reduce these risks to workers involved with construction, operation, and maintenance of the system. Alternative I-No Action does nothing to prevent further contaminant migration to the surface water. Risks currently posed by the contaminated groundwater would not be expected to decrease under the No Action scenario. Although the site is currently posted advising against trespass, the potential for direct contact with contaminated surface water is not completely mitigated, and the No Action alternative does nothing to reduce the' potential for direct contact with the surface water. 2. Compliance with ARARs addresses how the proposed alternative complies with all ARARs of Federal and more stringent State environmental laws and also considers how alternatives comply with advisories or other guidance that do not have the status of laws, but that the U.S. Environmental Protection Agency (EPA) and the State have agreed should be considered for protectiveness, or to carry out certain actions or requirements. 15 ------- All alternatives, except the no action alternative, will generally comply with ARARs of State and Federal environmental or facility siting laws specific to this interim action. The following State and Federal ARARs are specific to this. interim response action: : * * CERClA Act 307 Federal Clean Water Act (CWA 40 CFR part 403) Michigan Soil Erosion Sedimentation Control Act of 1972 (Act 347) Michigan Water Resources Commission Act, 1929 PA 245, as amended Michigan Goemaere-Anderson Wetland Protection Act of 1979 (Act 203) * * * * 3. long-term Effectiveness and Permanence 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. This interim response action is not intended to be permanent, but is intended to stop the flow of contaminated groundwater into Mill Pond Creek until a site-wide remedy can be implemented (2 to 3 years). It is possible that the interim response action system may become incorporated into the final remedial action for the site. The No Action alternative would not be an effective long-term solution to the problem at the site, as it does not address existing or future site risks. Alternatives 2 through 4-8 provide the greatest reduction in the potential for exposure to surface water contami nants. These a 1 ternat i ves are expected to reduce contami nant concentrat ions in Mill Pond Creek by e 1 i mi nat i ng further discharge of contaminated groundwater. 4. Reduction of Toxicity, Mobility or Volume Through Treatment refers to the ability of a remedy to meet the preference stated in Section 121(b) of CERClA, for remedies that involve treatment to reduce permanently the toxicity, mobility, or volume of hazardous substances and contaminants. Alternatives 2 through 4-8 would nearly eliminate the toxicity, mobility, and volume of organic contaminants in the site's groundwater because of contaminant destruction. The contaminants are removed via carbon adsorption, and are destroyed during the off-site reactivation of the carbon. The No Action groundwater alternative does not reduce toxicity, mobility, or volume except through volatilization and the slow processes of biodegradation. Short-term Effectiveness addresses the ability of alternatives to manage risks during t~e construction and implementation phases, and reduce immediate risks posed by the hazardous materials present. During the design and construction of the selected alternative, the short-term risks potentially posed to the community and workers can be effectively eliminated through proper engineering measures and protective equipment for workers. Al ternatives 2 through 4-8 present simil ar short-term ri sks to workers and community. The alternatives 4, 4-A, and 4-8, which include further 5. 16 ------- excavation, have slightly higher short term risks from dust exposure during the excavation activities. . Impacts to the environment vary between alternatives. Alternatives 3, 4, 4-A, and 4-8 would have construction effects on the flood plain from drill rigs or heavy machinery necessary to implement these alternatives. Alternatives 3, 4, 4-A, and 4-8 would potentially cause some draining of the flood plain and Mill Pond Creek. Drainage of the creek would be for a shorter duration under alternative 4-8. An additional environmental impact, under alternatives 4, 4-A, and 4-8, is possible.siltation of the creek from excavated soils. This would need to be mitigated by use of engineering controls during and after construction. Remedial action objectives would begin to be met after start-up of the system. Sampling of monitoring wells on the site will be continued as needed until groundwater cleanup is complete. This criteria does not apply to the No Action Alternative. 6. Implementability is the technical and administrative feasibility of a remedy, including the availability of goods and services needed to implement the chosen solution. Technical feasibility: The individual technologies used in each of the action alternatives are conventional and well documented. Unusual features are not anticipated to be required for any of the alternatives but will be resolved during the design phase, if encountered. There are no differences in the alternatives' ability to be monitored for effectiveness. Administrative feasibility: Alternatives 2 through 4-8 are more administratively feasible than Alternative 1, due to the fact that they address the interim response act i on objectives at the site. A lternat i ves 2 through 4-B requi re similar coordination between Agencies and other potentially affected interests. The No Action alternative would require substantial ongoing review efforts by the State. . Availability of services and materials: The technologies used under each of the action alternatives are conventional and readily available. 7. Cost includes capital and operation and maintenance costs. The costs of individual alternatives are detailed above. The No Action alternative has no direct costs associated with it. The alternatives with an interception trench are more costly than those without. 8. Support Agency Acceptance indicates whether, based on its review of the Feasibility Study and Proposed Plan, the support agency concurs, opposes, or has no comment on the preferred alternative. The EPA has chosen not to review the selection of this interim action at this time. The MDNR anticipates the EPA would concur with the remedial alternative chosen for this interim response action, due to the fact that the remedy has been 17 ------- se 1 ected in comp 1 i ance wi th the NCP, is protect i ve to human health and the environment, and meets the requirements of Act 307 which are more stringent that the NCP. 9. Community Acceptance is detailed in the attached Responsiveness summary. Sped fic comments received from area residents indicate that the Community supports the preferred interim response action, but would prefer immediate implementation of a final remedial action for the entire site. The Selected Remedy The preferred alternative for the interim response action is Alternative 2, with minor modifications. The modifications are due to the lack of information about contami nant d i stri but i on and concentration in the fl ood p 1 a in area. Th is alternative incorporates additional groundwater and soil sampling of the flood plain area. The preferred ~lternative includes: * The installation of 4-inch diameter groundwater purge wells on the bluff to the extent necessary to capture the contaminated groundwater plume and prevent further discharge of the contaminated groundwater to Mill Pond Creek. * Extraction of the contaminated groundwater and treatment in Koch's GAC treatment system with subsequent discharge to the Whitehall Area POTW. Sampling of the soil and groundwater in the flood plain area, during or prior to the installation of the bluff purge wells, to determine the extent of contamination in this area. Results of this investigation will be evaluated to determine whether residual contaminants, if present, will continue to discharge to Mill Pond Creek and pose a threat or potential threat to human health and the environment. If it is determined that it is necessary to mitigate the threat or potential threat posed by any such contamination, additional response actions will be taken. This will include the installation of purge well points in the flood plain (Alternative 2-A). . * 1. Attainment of Goals The MDNR has determined that the interim response action selected provides the best balance among the nine criteria and meets the requirements of CERCLA and Act 307. . 2. Compliance Points Compliance points to .be measured during the course of the interim response action, to determine the progress towards and attainment of protective cleanup levels, are: analysis of the treatment system effluent to directly determine the effectiveness of the treatment and to prevent the release of inadequately treated chemicals to the Whitehall Area POTW; and, monitoring well sampling and analysis to determine the effectiveness of the extraction treatment system at halting the 18 ------- flow of contaminated groundwater. Specifically, the area of attainment to be monitored for the completion of the interim response action includes the groundwater, surface water, sediments, and soils in and adjacent to Mill Pond Creek. Cleanup will be measured against those levels listed in Table 1. 3. ContinQencies Some minor changes may be made to the remedy as a result of the design studies. However, the cleanup goals must be met by the remedy that is implemented. Statutory Determinations The selected remedy will control and reduce risks associated with the Chemicals of Concern in the interim response action area of concern. The statutory requirements of CERClA Section 121 and Act 307 will be satisfied to the extent practicable with the implementation of the chosen interim response action. The following is an enumeration of how the selected remedy addresses each requirement. 1. Protection of Human Health and the Environment The selected interim remedy will provide adequate protection of human health and the environment through the use of treatment technologies. At completion of this interim response action, the risk from exposure to contaminated surface water, sediments and soil will be reduced to levels considered protective by the Act 307 Rules criteria and the,NCP. Risks associated with contact or consumption of site groundwater will decrease over time because the extraction and treatment system will reduce the concentration of all groundwater and surface water contaminants toward the cleanup levels specified in Table 1. 2. Compliance with ARARs The remedy selected will meet or attain the Federal and State ARARs and will be implemented in a manner consistent with these laws. In particular, the interim response action selected for implementation at the Muskegon Chemical Company site is consistent with the NCP, Act 307, and with Act 245. The groundwater and soil cleanup standards chosen for this site are based on Act 307 Rules. Criteria for complying with the Type A, 8, or C cleanups are contained in Michigan's Act 307 Rules. The substantive provisions, Parts 6 and 7 of the Act 307 Rules, are considered ARARs for the remedial action to be undertaken at the Muskegon Chemical Company site. These Rules require that remedial actions shall be protective of public health, safety, and welfare and the environment and natural resources (R299.5601(1)). The Act 307 Rules specify that this standard be achieved by a degree of cleanup which conforms to one or more of the Type A, B, or C cleanup criteria. A Type A cleanup generally achieves cleanup to background or non-detectable levels (R299.5707); a Type B meets risk-based cleanup levels in all media (R299.5709, 5711, 5723, and 5725); and Type C cleanup is based on a site-specific risk assessment which considers specified criteria (R299".5717 and 5719). The selected remedy utilizes a combination of Type A and B criteria and meets this ARAR. 19 ------- 3. Cost Effectiveness The compari son of cost effect i veness versus protect i veness ach i eved is the primary factor for the selection of the combination of preferred alternatives for the Muskegon Chemical Company site. The selected remedy outlined above affords overall effectiveness when measured against the five CERCLA Section 121 criteria and the nine criteria from the NCP, and costs are proportionate to the protectiveness which will be achieved. Utilization of Permanent Solutions and Alternative Treatment (or resource recovery) Technologies to the Maximum Extent Practicable The preferred remedy employs .permanent solutions and treatment technologies to the maximum extent practicable for this interim response action. 4. 5. Preference for Treatment as a Principal Element The principal threat at this site, the contaminant source area, will be addressed in the final remedy "for the site. As a result, the satisfaction of this preference, for the site as a whole, will be addressed at that time. The principal element of the selected interim remedy is the treatment of the contaminated groundwater. This interim remedy is protective of publ ic health and the environment. . 20 ------- GLOSSARY Administrative Order by Consent - An agreement, provided for by CERCLA or MERA, between the EPA or the MDNR and a potentially responsible party(s) to perform removal and/or remedial actions at a site. Administrative Record (AR) - An official record comprised of all documents . pertinent to the decision making process of selecting remedial action to be taken at a site. Aquifer - A geologic formation, group of formations, or part of a formation capable of yielding a. significant amount of groundwater to wells or springs. ARARs - (Applicable or Relevant and Appropriate Requirements) Legal Requirements promulgated under Federal, State, or local law that establish cleanup requirements for Superfund sites. Biological Degradation - A process where microorganisms modify the chemical nature of contaminant molecules by breaking large molecules into fragments. The resulting products generally have lower toxicity than the original contaminant. Carbon Adsorption - A technique used for the removal of dissolved contaminants from leach~te' and contaminated groundwater by adsorption onto granular activated carbon. CERCLA - Comprehensive Environmental Response, Compensation, and Liability Act of 1980, also known as Superfund: Amended in 1986 by the Superfund Amendments and Reauthorization Act (SARA). Cleanup Level - The contaminant concentration goal of the remedial action, i . e., the concentration of a groundwater contami nant to be achi eved through remedial action. Cone of Influence - The cone shaped depression of groundwater around a purge well that is affected by pumping water from the well. Any groundwater in this area or flowing into this area will be captured by the purge well. Contaminant Plume - An area of contamination with measurable horizontal and vertical dimensions that is suspended in and often moves with groundwater. Extraction - A method to withdraw contaminated groundwater through a well or a series of wells, which can then be treated prior to discharge. Feasibility Study (FS) - A study which evaluates different methods to remediate, cleanup, or otherwise resolve the contamination problems identified in the Remedial Investigation (RI). GAC - Granular Activated Carbon, a medium upon which organic contaminants are adsorbed in a treatment system. 21 ------- National Contingency Plan (NCP) - Policies and procedures that the Federal Government follows in implementing responses to hazardous substances. National Priorities list (NPl) - A federal roster of uncontrolled hazardous waste sites that actually or potentially threaten human health or the environment and are eligible for investigation and remediation under the Superfund program. Operation and Maintenance (OlM) - Operation and maintenance costs are post-construction costs necessary to maintain the future effectiveness of a remedial action. These costs include maintenance materials and labor costs, operati ng 1 abor costs, energy, di sposal of residues, insurance, taxes, costs of periodic site reviews, and licensing. Proposed Plan - A document that describes the site; summarizes key findings of the Remedial Investigation and Feasibility Studies; provides a brief .analysis of remedial alternatives under consideration; identifies the alternative preferred by EPA and the State; and provides the public with information on how they can participate in the remedy selection process. Purge Well- The wells through which extraction takes place. Remedial Action - An action that is implemented to address a direct threat to human health or the environment. Remedial Investigation (RI) - A study which examines the nature and extent of contamination problems at the site. Responsiveness Summary - The document in which the Agencies' address all comments received during the public comment period. 22 ------- ; RESPONSIVENESS SUMMARY MUSKEGON CHEMICAL SUPERFUND SITE WHITEHAll, MUSKEGON COUNTY, MICHIGAN OCTOBER 30, 1992 Context Th is Respons i venes s Summary has been prepared to meet the requ i rements of Sections 113 (k) (2) (B) (iv) and 117 (b) of the Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA), as amended by the Superfund Amendments and Reauthorization Act of 1986 (SARA), which require the United States Environmental Protection Agency (EPA) to respond .. .. to each of the significant comments, criticisms, and new data submitted in written or oral presentations. . ." on a Proposed Plan for Remedial Action. As noted, public participation in Superfund projects is required by SARA. Comments received from the public are considered in the selection of the remedial action for the site. The Responsiveness Summary serves two purposes: to provide the EPA with concerns regarding the remedial alternatives, and to show members of the community how their comments were incorporated into the decision-making process. . The Mi chi gan Oepartmen.t of Natural Resources (MONR), as 1 ead agency for the Muskegon Chemical Company (MCC) site, has prepared this responsiveness summary. Site Overview The Muskegon Chemi ca 1 site is located southeast of the ci ty of Whi teha 11, Muskegon County, Michigan. The site consists of 19.6 acres which includes the Muskegon Chemical site and the vertical extent of contamination originating from the facility. Contamination from the facility is known to have miqrated 1/2 mile southwest to Mill Pond Creek. The Preferred Alternative for this site consists of placing purge wells along the bluff adjacent to and up gradient from Mill Pond Creek. Further investigations and treatment are planned to study the flood plain to determine the nature of the contamination. Written and oral comments received from the public were in favor of the Preferred Alternative, however, .local residents expressed a strong concern for expedient cleanup of the groundwater. Backqround On Community Involvement History The Koch Chemical facility has been a source of great concern for the residents of Whitehall since contamination was discovered at the site in the late 1970's. 23 ------- In June 1979, homeowners in the vicinity of the Muskegon Chemical facility began a letter writing campaign concerning a plant explosion which occurred in March of that year. Fearing that the explosion had threatened publ ic health, the residents contacted the Michigan Department of Natural Resources (MDNR). . The Air Quality Division of the MDNR received numerous complaints concerning noxious air emissions allegedly originating from the Muskegon Chemical Company facility. In the early 1980's, residents initiated a meeting with Muskegon Chemical representatives in order to discuss the chemicals and processes used at the facility. In addition to meeting with the company representatives, residents took their concerns to the Whitehall City Council. The City of Whitehall became formally involved with the contamination at the site in February 1980. The City Council passed a resolution requiring the company to address the groundwater contamination at the site. The MCC site was added to the National Priorities List on February 21, 1990. As the lead agency for the site, the MDNR published the Community Relations Plan (CRP) for the site, which identified concerns expressed by the residents and local officials of Whitehall. Concerns The Community Relations Plan (CRP) for the Muskegon Chemical Superfund Site was completed in February 1991. At that time, the following concerns were identified. * The potential effects of groundwater contamination on public health. The effect the contamination would have on property, the local wildlife and area recreation. * * The inadequacy of the existing purge well system to capture the groundwater plume. * The poor flow of information from the MDNR to the public in the past. The lack of knowledge about the Superfund program. * * Whom will be responsible for the cost of the site cleanup. Effects And Outcomes Of Concerns Some of.. the key concerns ment i oned above were addressed duri ng the site investigation are described below. 1. Residential wells and area surface water sediments were sampled during the Remedial Investigation (RI). The results from these residential sampling rounds were transmitted to the public through progress reports, personal correspondence~ and the Engineering Evaluation and Cost Analysis (EEjCA) report. Surface water and sediment sampl ing results were reported in the RI. 24 ------- 2. 3. 4. 5. 6. Effects on wildlife issues will be addressed' in the Risk Assessment report, however, studies were not conducted concerning property values or recreation as this was out of the scope of the Superfund program. Groundwater sampl ing conducted during the RI demonstrated that the existing purge well system was not properly capturing the contaminant plume. This problem will be addressed by the interim response action. To improve the information flow from the MONR to the community, progress reports are published on a regular basis. A Citizen Information Committee (CIC) was also formed to help keep the members of the community informed about activities at the site. Frequent telephone contacts are made to insure that information is flowing in all directions. All of these activities are on-going. In order to inform the public about the Superfund program, fact sheets are sent out describing the purpose of the program. Also the Superfund program and its various aspects have been reviewed and discussed with the public during public meetings and CIC meetings. The responsibility for conducting and funding the cleanup was estab 1 i shed in a Consent Order between the MONR and Koch Chemi ca 1 . Under this Order, Koch Chemical is responsible for the RI and the Feasibility Study (FS), as well as the interim response action. Summary Of Public Comments And Responses Questions and comments were received during a Public Meeting held at Whitehall City Hall on April 30, 1992, from 7:00 p.m. to 9:00 p.m. Written comments were also received during the public comment period which ran from April 14, 1992 to May 14, 1992. Following is the response to public comments regarding the interim response action Proposed Plan for the Muskegon Chemf~al Site. Comments Received at the Public Meetinq The following questions and comments were received at the public meeting. The MONR, EPA, and Muskegon Chemical representatives addressed the following questions during the proceedings. The following answers are presented for further clarification. Comments have been arranged into 3 categories. 1. General Questions and Comments Why does it...take so 'ong to perform a cleanup action after a study has been conducted? There are many time requirements, such as the 30-day public comment period, required as part of the Superfund process. In addition, it takes time to design the cleanup plan, review the plan, and procure contractors to perform the work. 25 ------- What ti8e constraints exist that prolong the study of the site and its plume? The RI report is currently under review by the MDNR, and the draft Risk Assessment is due to the MDNR by the end of February. Following the issuance of the final RI and risk assessment, is issuance of the FS report and a Record of Decision (ROD) for the site as a whole. This process generally takes 18 months to two years. How long does it take to study the groundwater flow? At this site the remedial investigation began in July 1991, and the results from the final round of groundwater sampling were available in March 1992. All of this information will be used to evaluate and select the final remedy at the site. Is there a set number of personnel that will aid in a faster cleanup? There is not a set number of personnel that will aid in a faster cleanup. The cleanup is currently progressing at a very fast rate considering the complexities at the site. Data collection, analysis, and evaluation is a very time consuming process, that can not be avoided. High quality data is necessary for adequate remedy selection. Additional personnel are assigned to the project as needed. How many full time personnel work on this site (cleanup)? . The number of full time personnel working on this cleanup depends on the stage of the cleanup process. During the field investigation, the state had 4 to 5 full time people on staff and/or under contract, and Koch/CH2M HILL had 10 to 15 full time people. Currently, there is probably 1-2 one full time people for the state. and at least 1-2 full time persons for Koch/CH2MHILL working on the project. Is a fish consumption advisory in effect on Hill Pond Creek? The original fish consumption advisory was initiated by the city because the State did not have adequate information about the contaminants to make a determination on the need for a fish advisory. At that time a division of the 1 oca 1 government deci ded to post the creek due to the uncerta i nty about the contami nants. It was 1 ater determi ned that there were not 1 eve 1 s of the contaminants which would require a fish advisory in Mill Pond Creek. 2. Concerns About The Koch Chemical Facility When will the Koch Chemical Facility be fully decommissioned? The production at the processing plant ended in Oecember 1991. All chemicals and the equipment used in processing were removed from the site, and the plant decommissioning was completed by the end of 1992. At that time all equipment, except those needed to treat the purged groundwater, was removed from the site. 26 ------- What is being done with the processed chemicals and equipment currently at the facility? . The processed chemicals at the plant will be distributed in three ways. First, the processed chemicals and finished product will be sold to Koch's previous customers. Second, some of the unused raw materials are being sold back to the various vendors. Third, all other chemicals will be neutralized and disposed of according to solid waste or hazardous waste requirements. Plant equipment will be cleaned, dismantled, and sold. Some of this equipment will be sent to Koch's sister plant in Kansas for reuse. Are there plans to remove the buildings (on site) to get at the source of the contamination? The MDNR is not aware of any plans to remove the buildings on site at this time. There are technologies available, such as soil flushing, where it may not be necessary to remove the buildings to get at the contamination. The overall remedial action plan for this site requires Koch to look at options which include removing the buildings in order to get at the. source of the contamination. . Why is the company not considering removing the buildings on site? It is Koch's intention to hold the property until the site is certified clean by the MDNR and the EPA. When the certification is received from both agencies, Koch will then offer the property for sale. If the buildings can be left on site, Koch would b~ adding additional value to their land. Will the Koch Chemical property be leased or rented for use? As mentioned above, Koch pla~s to hold on to the property until the property is certified clean by the MDNR and EPA. Once this certification has been received, then the property will be ready for sale. . Does Muskegon Chemical have any liability contracts with the previous owners of the property? . It is not known at th is time whether or not Koch Chemi ca 1 has a 1 i abi 1 ity contract with its previous owners. The company has agreed to conduct the interim response action. If the company also agrees to conduct the final remedial action at the site, the option of further action against the previous owners will be up to the Koch 'Chemical Company. 3. Technical Concerns What is the rate at which Koch is pumping it's existing purge wells? What will be the pumping rate~after the new purge wells are in place? Koch has a permit with the Whitehall Area Publicly Owned Treatment Works (POTW) to discharge 150,000 gallons per day. Koch is pumping the existing purge system 27 ------- at 150,000 gallons a day. The company has no intentions to exceed this permit limit, and will take the necessary steps to prevent this. Calculations in the EE/CA estimate that discharge of contaminated groundwater to Mill Pond Creek can be stopped without exceeding the 150,000 gallon per day discharge limit. This will however, require re-distribution of the pumping rates of water from the various purge wel'ls in order to capture the contaminat~d groundwater, prevent discharge to the creek, and avoid exceeding the 150,000 gallons per day limit. When the new purge wells are pl~ced on the bluff, will these wells increase the purge capacity? When the new purge wells are placed in the bluff region of the plume, these wells will be pumped at a greater rate than the purge wells already present. The pumping rate of the older wells will be reduced once the bluff wells are in operation. The pumping rate of the bluff wells, combined with the pumping rate of the older purge wells will result in a 150,000 gallon a day total pumping rate. Win the interim response action being conducted at the creek be visible from the White Lake Drive? Currently it is possible to see the site from White Lake Drive. One road already exists into the site area. The plan is to have a service road in order to get to the various well 'points in the bluff area. There are also wells on the north side of White Lake Drive. These already exist and are visible from the road. The service road south of White Lake Drive and the monitor wells north of White Lake Drive are all that will be visible to the casual passer-by. When will the interim.response action purge wells be put into place? When will additional purge wells be put into place? It is anticipated that the interim response action purge wells will be put into place sometime during the late winter or early spring of 1993. These wells will stop the discharge of contaminated groundwater to Mill Pond Creek. Additional purge wells may be necessary as part of the overall remedial action at the site. These wells would be installed after the completion of the RI/FS. What will be done if, after the purge wells are put into place, it is detenmined that contamination is still entering Hill Pond Creek? If it is determined that after the bluff purge wells are in place that contaminants are still entering the creek, then the purge flow will have to be redistributed to capture the contamination. It is estimated that the bluff purge wells will require a pumping rate of 26 gallons a minute. This option also allows the company to pump water in the various "hot spots" in the plume area. 28 ------- Why can't Koch supply as many carbon filtered wells as necessary to clean up the contamination so it can go right back into Hill Pond Creek clean, so we don't have to worry about it effecting the wetlands. Why do we have to think in tenms of public treatment systems in which the public will have to pay for? Why can't we expect Koch to clean up the water themselves? It is the intent of the interim response action to place into operation a system that will prevent contaminant discharge to Mill Pond Creek in the very near future rather than a few years down the road. As part of the eva 1 uat i on process, Koch/CH2M HILL evaluated various treatment options. Due to the fact that this option can be implemented now with the approved discharge to the POTW, this option allowed for a faster response than construction of a new treatment system with discharge to the creek: Final remedial action evaluation will include consideration of treatment on-site with discharge to Mill Pond Creek. As part of the agreement with the Whitehall Area POTW, Koch pays for the treatment of their pretreated waste water. Therefore, the treatment costs will not be paid for by the public. Is the discharge mentioned in the interim response action considered a part of the existing discharge already going to the wastewater treatment system? The discharge to the wastewater treatment plant is a part of the existing authorized discharge. . Koch is authorized under its contract with the city and county to discharge up to 150,000 gallons a day of processed water and treated groundwater. Since' the plant shut down, the company has been able to discharge more groundwater as it no longer has processed water to discharge. The discharge mentioned in the interim response action will not ex.ceee the established dischar~e limit. - . What level of contaminant concentration can be released to the wastewater treatment plant? The contract agreed upon by the Whitehall Area POTW and the company calls for a level of half a part per million (0.5 ppm). How are contaminants treated at the wastewater treatment plant? The chemicals, at the concentrations that they are found in the groundwater, are bi odegradabl e and are affected by the treatment processes at the wastewater treatment plant. The information developed by the county waste treatment system indicates that the chemicals are treated to a nondetectable level. Although the wastewater treatment plant can treat down to a nondetectable level, federal and state law requires that industries pretreat their wastewater prior to delivery to the wastewater treatment pl ant. As mentioned above, Koch pretreats the purged groundwater down to 0.5 ppm. Is there a treatability problem with the chemical Chlorex? In the past there was a treatability problem when Muskegon Chemical began sending its processed waters to the treatment plant. This problem was due to high concentrations of Chlorex in the waste water. In response, the Whitehall Area POTW requi red that Muskegon Chemi ca 1 treat thei r waste water down to a 1 eve 1 that 29 ------- could be handled by the treatment plant. As a result, the company is now required to treat down to 0.5 ppm before sending its wastewater to the treatment facility. A supervisor at the treatment facility indicated that since Koch started treating its wastewater down to 0.5 ppm, there has not been a treatability problem at the facility. If the wastewater treatment plant will not accept the water from the purge well system, what other options are there for disposal of the purge water? " If it is determi ned that the wastewater treatment plant cannot accept the pretreated water from the purge system, then treated wastewater would have to be discharged to the groundwater or surface water. If this is the case, a groundwater or surface water. di scharge permit wi 11 be needed and appropri ate treatment performed. The chemicals which are in the groundwater, do these bioaccumulate in fish and wi ldl ife? The chemicals which have been released to the groundwater do not bioaccumulate in fish or wildlife species. How much water enters Hill Pond Creek in the plume area? It is currently estimated that the groundwater flow from the plume area into Mill Pond Creek is 150 gallons per minute. Are there plans to drain the flood plain in onder to purge the contamination? The plan of action to be taken at the flood plain is dependant on the outcome of the investigation of the flood plain. If it is determined that the flood plain is contaminated, then the plan of action with the least impact on the area will be the use of well points for groundwater extraction. The well points may drain the f1 ood p 1 ai n. The extent of the dewateri ng, if any, by the we 11 poi nts is not known at this time, but is expected to be minimal due to the small area of influence by the well points. Why are all alternatives considered for cleanup based on Koch's discharge limits to the local wastewater treatment plant? Koch determined that they could capture the contamination entering into the creek within the previously established discharge limit. As a result, Koch could continue using the exi~ting activated carbon treatment system with discharge to the wastewater treatment plant. It was determined that this would allow them to carry out the interim response action in an expeditious fashion. What impact has the site had on the Whitehall municipal aquifer located to the northeast of the Koch facility? During the RI, monitor wells and soil borings were placed northeast and northwest of the site, to delineate the limits of the plume. Contamination was detected in only one well on the northern boundary. The Contaminant was 30 ------- 1,2 Dichloroethane at 1.7 parts per billion. A monitoring well was installed at the depth that contamination was encountered and no further contamination has since been detected at that location. No contamination was detected at any of the other background locations. Based on the information that is available at this time, the site does not pose a threat to the new Whitehall Municipal well located approximately 1.5 miles to the northeast. What intentions are there to check the municipal aquifer for contamination? The study conducted under the Rl indicates that the groundwater contamination plume travels southwest towards Mill Pond Creek. There are no indications of any groundwater movement towards the city of Whitehall municipal well. We do not anticipate further investigation of the aquifer to the north under this consent agreement. . Has there been a formal presentation to the Muskegon County Board of Works concerning the discharge to the wastewater treatment plant? Prior to Koch Chemical's acquisition of the site, there was a presentation to the Board when the contract between the Muskegon Chemical Company and the Whitehall Area POTW first originated. The changes proposed in the interim response action will not change the quantity or quality of the water entering the wastewater treatment plant, which is allowed under terms of the existing contract. The company is willing to make another presentation to the Board, if needed, in order to clarify any misunderstandings. Comments Received In Writing Only two questions were received in writing from the public during the public comment period. As mentioned before, the citizens have encouraged the MDNR and Koch Chemical to move toward a swift implementation of the interim response action. What is the efficiency of the purge well system to capture the contaminants as the plume progresses? The efficiency of the existing purge well system is unknown. Based on sampling observations, we are aware that the existing system is not compl,etely capturing the contaminant plume. Is the HDNR or Koch Chemical aware of a problem with treating the chemical Chlorex? The Whitehall Area Wastewater Treatment Plant operator has indicated that the plant does not have a problem with Chlorex at the current discharge limit of 0.5 ppm. 31 ------- |