Amendment to the Record of DecisionSDMS DocID 2072442

Operable Unit 4 - Ground Water Component

Fike/Artel Site

I. Introduction

Site Name:

Site Location:

Lead Agency:

Support Agency:

Fike/Artel

Nitro, West Virginia

U.S. Environmental Protection Agency, Region HI (EPA)

West Virginia Department of Environmental Protection (WVDEP)

EPA issued a Record of Decision (ROD) for the Fike/Artel Site for Operable Unit Four (OU4) that was signed on September 28,2001. This Amendment to the ROD is issued in accordance with Section 117(c) of the Comprehensive Environmental Response, Compensation, and Liability Act, as amended by the Superfund Amendments and Reauthorization Act of 1986 (CERCLA), 42 U.S.C. §9617(c), and 40 C.F.R. §300.435(c)(2)(ii). This Amendment has been prepared to document the nature of the change made to the selected remedy identified in the OU4 ROD; to summarize the information that led to the making of the changes; and to affirm that the amended remedy complies with the statutory requirements of CERCLA Section 121,42 U.S.C. §9621.

This Amendment is based on the Administrative Record for this Site and is incorporated into the ' Administrative Record in accordance with 40 C.F.R. §300.825(a)(2). The Administrative Record is located at the EPA Region in office, 1650 Arch St., Philadelphia, Pennsylvania and at the Nitro Public Library, 1700 Park Ave., Nitro, West Virginia and is available to the public on the internet at www.epa.gov/arweb.

West Virginia has provided support to EPA throughout the reevaluation process. WVDEP is in agreement with In Situ Biosparging supplemented with the addition of peroxide and/or nutrients, as necessary, as the revised selected remedy for ground water.

The 2001 ROD selected extraction and treatment of groundwater and required additional groundwater investigation to define the extent of groundwater contamination. Recent groundwater studies conducted at the Site support EPA’s selection of a new remedy. This amendment would modify the cleanup by eliminating the requirement to extract and treat groundwater. Instead, this amendment would require in situ biosparging by delivering air and/or peroxide and other nutrients to contaminated groundwater through a series of injection devices to

. stimulate biodegradation, which would remediate the ground water to the cleanup levels

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established in the 2001 ROD.

II. SUMMARY OF THE SITE HISTORY AND SELECTED REMEDY IN OU4 ROD

The Fike/Artel Site is located approximately 1.1 miles south-southwest of the intersection of Interstate 64 and State Route 25, in the town of Nitro, West Virginia (See Figure 1). The Site consists of an 11.9 acre former batch chemical production plant (referred to as the Chemical Plant) and a 0.9 acre former Cooperative Sewage Treatment Plant (referred to as the CST), as well as the areal extent of contamination and suitable areas in very close proximity to the contamination necessary for implementation of response action, as described in the 2001 ROD at footnote 1. The CST is located approximately 500 feet west of the Chemical Plant and is not contiguous with the Chemical Plant property.

The Chemical Plant was a small volume chemical manufacturing plant, constructed over the razed remains of a World War I gun powder plant, that specialized in the development of new chemicals, custom chemical processing, and specialty chemicals. The Chemical Plant began operations in 1951 under ownership of Roberts Chemical Company. In 1971, the name was changed to Fike Chemicals, Inc. and later to Artel Chemical Company.

More than 60 different chemicals were produced throughout the operational history of the plant by batch reaction processes. The Chemical Plant consisted of chemical production areas, office and laboratory buildings, three waste lagoons, and drum and waste burial areas.

The CST was constructed between 1966 and 1968 to treat sanitary and industrial wastewater and storm water runoff from the Fike Chemical Plant and an adjacent trucking terminal. Storm water and wastewater were directed from the Chemical Plant to the CST using the WWI-era gravity- flow sewer system.

The Fike/Artel Superfund Site was placed on the National Priorities List (NPL) on September 1, 1983. EPA initiated a removal action in 1988 which consisted of removing and/or treating 744,000 gallons, 34,000 pounds, and 1,000 cubic yards of hazardous materials.

EPA organized the long term clean-up activities into several operable units (OUs). From 1990 through 1997, several remedial and removal actions took place including: demolition of buildings, decontamination and dismantling of tanks, consolidation and off-site disposal of drummed material, excavation and off-site disposal of buried drums, and closure of the CST. As a result of these earlier actions, all of the buildings and tanks have been removed from the Site, and buried sources of wastes have been dug up and disposed of off-site.

In September 1994, EPA entered into a Consent Order with numerous companies to investigate the soils and ground water. In February 1997, EPA and WVDEP also, entered into a Consent . Decree with numerous companies to perform work at this Site. These companies formed a steering committee called the Fike/Artel Trust and have agreed to implement and pay for the .

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selected remedy pursuant to the terms of the Consent Decree.

In September 2001 EPA issued a Record of Decision (ROD) for OU4, which focused on the soils, sewers tod ground water at the Site. The soil component activities for OU4 included removal of a lagoon, disposal of remaining impacted materials from the Site, and construction of an asphalt cap for the CST and Chemical Plant areas to prevent exposure to contaminated soils.A chain link fence was also installed around the chemical plant property. The soil component activities for OU4 were completed on October 14,2003. A portion of the property is currently leased to a local business. >

In implementing the 2001 ROD, the PRPs also conducted a thorough investigation of the sewers. EPA and WVDEP approved the remedial action work plan for the sewers on September 12,2006.

The 2001 ROD selected remedy for ground water was the use of a pump and treat system to reduce concentrations of Contaminants of Concern (COCs) in ground water to levels which result in less than or equal to a 1 x 10'5 cumulative excess cancer risk1 * 3 and a Hazard Index less than 1.0, and achieve drinking water standards (MCLs and non-zero MCLGs). The 2001 ROD remedy for groundwater required additional investigation activities to define the extent of ground water contamination concurrent with the design of the pump and treat system.

III. REASONS FOR ISSUING THIS ROD AMENDMENT

This ROD amendment is for modifying the ground water component of the remedy for OU4.The 2001 ROD-selected remedy estimated that the contaminated ground water plume extended approximately 400 feet beyond the property line but required additional investigation to define the plume. A pump and treat remedy was selected as a means to contain and remediate the. contaminated plume. The ROD estimated that the pump and treat system would consist of seven extraction wells. However, the additional groundwater investigations required by the ROD, and pilot studies conducted by the PRPs subsequent to issuance of the ROD (collectively referred to herein as Pre-Remedial Design Investigations), have demonstrated that the plume extends almost 4,000 feet beyond the property line (see Figure 2) and that 39 extraction wells would be required.

Because the increased contaminant plume size would increase the area to be remediated, by a factor of ten, and would result in a cost of triple the original $12 million estimate, implementing the pump and treat remedy required by the 2001 ROD could be a fundamental change from the scope of work anticipated in the 2001 ROD:

Between 2002 and 2006, the PRPs conducted a Pre-Remedial Design Investigation (PRDI) consisting of several ground water studies to define the extent of ground water contamination, as

1A 1 X 1 O'5 cancer risk means the chance is one in one hundred thousand that one.extra

cancer risk may occur as a result of exposure to Site contaminants.

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required by the ROD, and in situ treatability studies. EPA has reviewed these studies and believes that the in situ technologies are superior to extraction because contaminated ground water would be treated while in the ground as opposed to being extracted to the surface for treatment above-ground via a pump and treat system.

The data collected from these investigations provided a better understanding of the ground water contamination. The PRDI work included the installation of twelve (12) cone-penetration testing (CPT) boreholes; 56 Direct-Push Technology (DPT) boreholes;, and 46 piezometers. Approximately 150 ground water samples were collected and analyzed. The majority of the 34 COCs were found in the area closest to the property line, whereas there are only a few COCs that have migrated 1,000 feet or more beyond the property line. The COCs that had migrated furthest from the Site could be amenable to natural degradation in the presence of sufficient oxygen.

The in situ treatability studies, conducted by the PRPs from October 2004 through March 2005, consisted of pilot-scale testing of three in situ, aerobic-based remedial technologies including biosparging, peroxidation, and aerobic co-metabolism. The results of the pilot scale tests demonstrated that these technologies have the potential to successfully treat the COCs.

A Focused Feasibility Study (FFS) was prepared by the PRPs in January 2006 to estimate the revised cost of the 2001 ROD-selected pump and treat remedy, based upon the increased plume size, and also to evaluate other remediation technologies.

The information from the investigations, the treatability studies, and the FFS provide the basis for EPA’s reconsideration of the ground waiter remedy selected for the Site. The EPA’s new preferred groundwater remedy, in situ biosparging with the addition of peroxide and/or nutrients based on field testing results and Monitored Natural Attenuation as a supplemental technology, would provide the same level of protection as the remedy selected for the Site in 2001 by effectively reducing the concentration of contaminants in the ground water to levels which are protective of human health and the environment. The preferred remedy is estimated to achieve this effect in a shorter time frame than active pumping and treatment of the groundwater. In addition, the Agency’s new preferred alternative would not result in the generation of residual wastes, and would result in a more cost effective cleanup. Those portions of the remedy for the Site, set forth in the 2001 OU4 ROD which are not addressed in this ROD Amendment, would remain in effect.

1. Scope and Role of This Action

This action addresses groundwater at the Site and is a component of the remedy selected in the 2001 ROD referred to as Operable Unit 4 (OU4). This action will be the final action for this Site. Previous removal and remedial actions (including OU1, OU2, and OU3) provided for the off-site disposal of hazardous wastes and the demolition of buildings and tanks. OU1 addressed the removal of surface drums and wastes contained in tanks while OU2 addressed the removal of

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tanks, equipment, and structures at the Site. 0U3 addressed the excavation and off-site disposal of buried drums.

The Remedial Action Objectives for ground water at the Site are to reduce the concentration of Contaminants of Concern (COCs) in ground water to acceptable levels and to ensure that ground water is not used for water supply until such COCs in ground water are reduced to levels which result in less than or equal to a 1 x 10'5 cumulative excess cancer risk and a Haizard Index less than ,1.0 and achieve drinking water standards (MCLs and non-zero MCLGs),

Currently, there are no known residential, commercial, or industrial users of ground water in the vicinity of the Site.

The OU4 ROD listed thirty-four (34) COCs for ground water. These COCs were detected in ground water within the property boundaries of the Site.

As discussed above, several groundwater investigations were conducted between 2002 and 2006. The data collected as part of these investigations defined:

• the subsurface soil conditions;• . the direction of ground water flow; and •• the extent of ground water contamination.

The results of the ground water sampling indicate that the major COCs are restricted to a certain set of organic chemicals. This amendment reduces the COCs to the 22 listed below:

1.2- Dichloroethane (1,2-DCA)1.2- Dichloropropane (1,2-DCP)1.3- Dimethyl-2-Thiourea (DMTU) HeptachlorHexamethyl Phosphoramide (HMPP) IronManganese .Tetrachloroethene 1,1,2-Trichloroethane Trichloroethene Vinyl Chloride

AldrinArsenicBenzenealpha-BHCBis (2-Chloroethyl) Ether (BCEE)bis (2-Chloroisopropyl) ether (BCIPE)bis (2-ethylhexyl) Phthalate (BCEP)Carbon TetrachlorideChlorobenzeneChloroform4,4-DDT

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\

2. Summary of Site Risks

The Site risks are unchanged from the 2001 ROD. Currently, the ground water at the Site is not used as a potable source, since potable water is supplied by a municipal water source. However, there is a possibility that ground water could be used in the future for drinking water. Several measures are in place to minimize the possibility of wells being installed in any area where there is Site-related groundwater contamination, including:

• A City of Nitro ordinance which prohibits extraction of ground water or drilling to obtain access to ground water west of Route 25 within the City of Nitro;

• An Amendment to the Deed of Restrictive Covenants which prohibits the use of ground water at or beneath the Fike/Artel property;

• A system with Miss Utility of West Virginia (MUWV) whereby MUWV notifies the Fike/Artel Trust when anyone requests a utility search-in the contaminated ground water plume area.

The 2001 ROD, which can be found on the Internet at www.epa.govarweb. provides a detailed explanation of human health risks if ground water is used for consumption or showering. The risk estimates for ground water in the 2001 ROD were based on future reasonable maximum exposure scenarios and were developed by taking into account various conservative assumptions about the frequency and duration of an individual’s exposure to the ground water, as well as the toxicity of contaminants. Drinking or taking a shower using the ground water in the vicinity of the Site'presents an unacceptable risk.

3. Remedial Action Objectives

The new Remedial Action Objectives (RAO) for ground water remain the same as those listed in the 2001 ROD, which are:

• Reduce concentrations of COCs in ground water to levels which result in less than or equal to a 1 x 10'3 cumulative excess cancer risk and a Hazard Index less than 1.0 and achieve drinking water standards (MCLs and non-zero MCLGs);

• Ensure that ground water is not used for water supply until concentration of COCs are reduced to levels which result in less than or equal to a 1 xl O'3 cumulative excess cancer risk and a Hazard Index less than 1.0 and achieve drinking water standards (MCLs and non-zero MCLGs).

The Preliminary Remediation Goal (PRG) for modifying the groundwater component of the OU4 ROD is to reduce the concentration of contaminants to drinking water standards or to concentrations which result in less than or equal to a 1 xlO'5 cumulative excess cancer risk and a

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Hazard Index less than 1.0.

Although the ground water is not currently used as a drinking water source, the goal of EPA’s Superfund Program is to return usable ground waters to their beneficial uses within a time frame that is reasonable given the particular circumstances of a site.

IV. SUMMARY OF REMEDIAL ALTERNATIVES FOR GROUND WATER

Remedial Alternatives for ground water for the Fike/Artel Superfund Site are presented below. The FFS Report evaluated five alternatives for remediation of ground water.

All of the Remedial Alternatives except Alternative 1 prohibit uses of the groundwater in the vicinity of the Site until cleanup levels are achieved. Measures such as health advisories, notices to deeds, or city ordinances are necessary as institutional controls to effectuate this prohibition.

Alternative 1 - No Action Alternative

Estimated Capital Costs: $0 Estimated Annual O&M Costs: $0.01 M Estimated Present Worth Cost: $0.15M

Regulations governing the Superfund Program generally require that the “no action” alternative be evaluated to establish a baseline comparison. Under this alternative, EPA would take no action at the Site to prevent exposure to the ground water contamination.

Alternative 2 - Ground Water Extraction, Treatment and Disposal

Estimated Capital Costs: $19.3M Estimated Annual O&M Costs: $1.3M Estimated Present Worth Cost: S38.7M

Under this alternative, which is the remedy selected in the 2001 ROD, ground water would be pumped to a treatment facility that would be constructed on-site. Due to the variety of hazardous constituents in the ground water, the treatment facility would include several treatment processes to reduce the level of contaminants. The treated ground water would be discharged to either a publicly owned treatment facility (Nitro Regional Wastewater Facility) or to the Kanawha River and would satisfy the requirements of the National Pollutant Discharge Elimination System (NPDES). The treatment plant would occupy approximately two (2) acres of land along the northern perimeter of the southern half of the Site.

In the 2001 ROD, EPA anticipated seven (7) extraction wells for costing purposes. Additional

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field work has shown that several of the contaminants migrated approximately 4,000 feet further from the property boundary, or ten times the original estimated plume. Based on the increased plume size, it is anticipated that the ground water pump and treat system would require 39 extraction wells, both within the property boundaries and outside of the property boundaries, that would operate for approximately 30 years (same time frame as estimated in 2001 ROD).

Under this alternative, measures such as health advisories, West Virginia licensed well driller , notification and/or membership to Miss Utility of West Virginia, as described on.page 6, would be implemented to prevent exposure to contaminated ground water.

-Alternative 3 - In situ Biosparging

Estimated Capital Costs: S1.8M Estimated Annual O&M Costs: S0.46M Estimated Present Worth Cost: $7.5M

In situ biosparging uses the forced delivery of air to contaminated ground water through a series of injection devices to aerate the ground water and thereby stimulate the in situ biotic attenuation of the organic COCs that are susceptible to aerobic biodegradation. After the ground water is aerated, the treatment may be enhanced with the injection of nutrients, microorganisms and/or peroxide to stimulate tho breakdown of the contaminants in the ground water.

This technology would most likely be installed in a series of phases, starting at the outer edge of the plume to prevent further migration of the contaminants. The installation would include a series of injection wells designed to deliver air under pressure to the base of the alluvial aquifer. For cost purposes, it is assumed that each phase will consist of 50 injection wells spaced 50 feet apart.

Each phase would require the installation and operation of a dedicated, permanently sited air- compressor and control system and the associated air-delivery piping system.

Under this alternative, measures such as health advisories, West Virginia licensed well driller notification and/or membership to Miss Utility of West Virginia would be implemented to prevent exposure to contaminated ground water.

Alternative 4 - In situ Peroxidation

Estimated Capital Costs: S2.5M Estimated Annual O&M Costs: S0.87M Estimated Present Worth Cost: $11.5M

In situ peroxidation involves the delivery of a solution of hydrogen peroxide to impacted ground

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water to stimulate the attenuation of organic COCs amenable to chemical oxidation. This technology would most likely be installed in phases, starting at the outer edge of the plume. This alternative would include the installation of peroxide injection devices to deliver peroxide to the alluvial aquifer. These devices would be spaced approximately 33 feet apart and would consist of a nested piping system designed to inject peroxide at three separate depth intervals in the aquifer. ;

Under this alternative, measures such as health advisories, West Virginia licensed well driller notification and/or membership to Miss Utility of West Virginia would be implemented to prevent exposure to contaminated ground water.

/ Alternative 5 - Monitored Natural Attenuation

Estimated Capital Costs: $0.08MEstimated Annual 0&M: Costs: S0.03M 'Estimated Present Worth Cost: $0.4M

I ’Monitored Natural Attenuation (MNA) refers to the reliance on natural attenuation processes to achieve site-specific remediation objectives within a time frame that is reasonable compared to that offered by other more active methods. The natural attenuation processes that are at work in such a remediation approach include a variety of physical, chemical, or biological processes that, under favorable conditions, act without human intervention to reduce the mass, toxicity, mobility, volume, or concentration of contaminants in groundwater.

MNA is evaluated at this Site only from the perspective of being used as a potential secondary remedial technology, for certain portions of the plume with lower concentrations of contaminants. MNA would be used following, or in conjunction with, the implementation of one or more of the active ground water remedial alternatives (e.g., Alternatives 2, 3 or 4).

Under this alternative, measures such as health advisories, West Virginia licensed well driller notification and/or membership to Miss Utility of West Virginia would be implemented to prevent exposure to contaminated ground water.

V. COMPARATIVE ANALYSIS OF ALTERNATIVES

Each of the remedial alternatives summarized above has been evaluated with respect to the nine (9) criteria set forth in the NCP, 40 C.F.R. Section 300.30(e)(9). These nine criteria can be categorized into three groups: threshold criteria, primary balancing criteria, and modifying criteria. The following is a summary of the evaluation of each alternative against the nine criteria.

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Threshold Criteria

1. Overall Protection of Human Health and the Environment

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.

Alternative 1, the “no action” alternative, would not be protective of human health and the environment because it does not reduce the concentration of contaminants and does not prevent the future use of the ground water. Alternative 2, 3, and 4 are protective because they will reduce the concentration of contaminants. Alternative 5, as a stand alone remedy, would not be protective of human health and the environment because some of the contaminants are not amenable to natural attenuation. Alternative 5, if implemented in conjunction with Alternatives 3 and 4 would be protective of the environment.

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

Compliance with applicable or relevant and appropriate requirements (ARARs) addresses whether or not a remedy will meet all Federal environmental and more stringent State environmental and facility siting standards, requirements, criteria and limitations, unless ARARs are waived under CERCLA § 121(d)(4).

Alternative 1 will not meet Federal and State drinking water standards. With Alternative 2, EPA anticipates that the ground water would be cleaned-up to ARARs which include drinking water standards. Discharges to surface water would comply with NPDES requirements. The ground water treatment plant may have air emissions which are subject to air regulations. Any control requirements would be determined through examination of state and federal regulations.

With Alternative 3 and 4, EPA anticipates that the ground water would be cleaned-up to ARARs which include drinking water standards. Both of these alternatives would include the installation of injection wells. The regulatory framework governing subsurface fluid distribution systems is established by the federal Underground Injection Control (UIC) program. Primary enforcement responsibility for implementing the UIC program in West Virginia has been delegated by EPA to West Virginia, pursuant to 42 U.S.C. § 1422. Regulations for the West Virginia UIC Program are set forth in the West Virginia Code of State Rules at W.Va. Code St. R. Tit. 47, § 13 (2006). The State UIC program regulates underground injections by five classes of wells, including wells designated as aquifer remediation related wells, which are defined as “wells used to prevent, control or remediate aquifer pollution, including but not limited to Superfund sites.” W.Va. Code St. R. Tit. 47, § 9A-2.8.C. (2006). The following specific requirements are applicable to

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the injection of air and peroxide/nutrients at the Site:

W.Va. Code St. R. Tit. 47, § 13.1.b. (2006) - No owner or operator shall construct, operate, maintain, convert, plug, abandon or conduct any other underground injection activity in a manner which causes or allows the movement of fluid containing any contaminant into underground sources of drinking water, if the presence of that contaminant may cause a violation of any primary drinking water regulation under 40 C.F.R. Part 142 or promulgated pursuant to W.Va. Code § 16-1-1 et seq., or may otherwise adversely affect the health of persons. The applicant for a permit shall have the burden of showing that the requirements of this paragraph are met.

Alternatives 3 and 4 would comply with the substantive requirements of the UIC Program regulations. No permit would be required.

Alternative 5, as a stand alone remedy would not cleanup ground water to ARARs, but as a supplemental remedy to Alternatives 2, 3, and 4 it would satisfy the ARARs.

Primary Balancing Criteria ,

3. Long-term Effectiveness and Permanence

Long-term effectiveness and permanence addresses the criteria that are utilized to assess alternatives for the long-term effectiveness and permanence they afford, along with the degree of certainty that they will prove successful.

Alternative 1 does not provide any long term effectiveness or permanence. Alternative 2 would pump and treat the ground water until clean-up levels are achieved and. permanently remove the contamination from the ground water.. However, it is anticipated that it could take 30 or more years before the ground water clean-up levels are achieved, as estimated in the 2001 ROD.

Alternatives ,3 and 4 would permanently remove COCs and would have long-term effectiveness and permanence. EPA anticipates that it would take 15 to 20 years to

' remediate the ground water with these alternatives.

Alternative 5 would remove some, but not all of the COCs and therefore may only be considered as a supplemental remediation technology for Alternatives 2, 3, and 4. The time frame would be the same as the technology it accompanies. This alternative includes monitoring to ensure that clean-up levels are achieved.

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4, Reduction of Toxicity, Mobility, or Volume of Contaminants through Treatment

Reduction of toxicity, mobility, or volume through treatment addresses the degree to which alternatives employ recycling or treatment that reduces toxicity, mobility, or volume, including how treatment is used to address the principal threats posed by the Site.

Under Alternative 1, no treatment is provided so the toxicity, mobility, and volume of contaminants would remain essentially the same. Alternative 2 would pump and treat the ground water, but would not reduce the volume due to the waste generated as part of the treatment processes.

Alternatives 3 and 4 would not involve pumping but would treat the contaminants in the ground water, which would reduce the mobility and volume of contaminants with no volume of wastes produced. EPA anticipates that these alternatives would reduce the overall toxicity of the impacted ground water.

Alternative 5 would treat some, but not all, of the contaminants in groundwater, which would result in an overall reduction of toxicity, mobility, and volume of some contaminants.

5. Short-Term Effectiveness

Short-term effectiveness addresses the period of time needed to achieve protection and any adverse impacts on human health and environment that may be posed during the construction and implementation period until cleanup goals are achieved.

Alternative 1 does not require time to implement and would not provide any short term effectiveness.

Alternative 2 would not be effective in the short term because administrative procedures and access agreements will be necessary to install extraction wells and approximately two miles of piping. There could be disruption to vehicle traffic in the surrounding area due to construction activities for construction of the ground water treatment system and associated piping, which is estimated to take two and one-half years. .Operation of the treatment plant would include delivery of chemicals, which could result in some leaks or

spills of chemicals. Precautions could be taken to minimize any spills.

Alternative 3 would be constructed in two or more phases and each phase would take approximately one year. EPA anticipates minimal administrative procedures and traffic disruptions. On-going treatment operations would include operation of ah air compressor and control system as well as continued monitoring to ensure the equipment is operating as designed. Various chemicals (biostimulants) may be used in the operation of the

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treatment system. There is some possibility that chemicals could be spilled, but measures can be taken to minimize any spills.

The short-term effectiveness of Alternative 4 is very similar to Alternative 3 with the exception of the types of chemicals that would be introduced into the ground water. Workers could be exposed to chemicals and there is some possibility of spills and leaks with the operation of Alternative 4. On-going treatment operations would include continued monitoring to ensure the equipment is operating as designed and the introduction of chemicals into the system.

Alternative 5 does not require any time to implement and does not provide any short-term effectiveness.

6. Implementability

Implementability addresses the technical and administrative feasibility of a remedy, : including the availability of materials and services needed to implement a particular option.

Alternative 1 is in place and would require no implementation.

Alternative 2, the pump and treat ground water system, is a Well-proven ground water remediation technology. Access to off-site properties for pumping wells and rights of way for the piping system make implementation of Alternative 2 difficult. Due to the high iron concentration in the ground water, wells and associated piping may require routine maintenance to unplug iron buildup in the piping system.

Alternatives 3 and 4 do not have the proven track record of a pump and treat system, however, EPA has evaluated the pilot studies which indicate that both technologies should address the major COCs at the Site. The materials and chemicals needed to implement Alternatives 3 and 4 are readily available. Neither alternative poses administrative challenges.

Alternative 5, as a supplemental remedy, is relatively simple to implement and would require the installation of monitoring wells.

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Cost. 7.

The Present Worth Cost for each alternative is:

Alternative 1 $ 0.15M Alternative^ $38.7M Alternatives $ 7.5M Alternative 4 S11.5M Alternative 5 $ 0.4M

Modifying Criteria

8. State/Support Agency Acceptance

The State of West Virginia supports the Preferred Alternative identified in this ROD Amendment for the remediation of Ground Water (Alternative 3 Biosparging supplemented with the addition of peroxide and/or nutrients, if necessary as determined by EPA, in concert with Alternative 5 - Monitored Natural Attenuation).

9. Community Acceptance

The PRPs retained the services of a public relations firm to facilitate a community liaison panel with representatives from the community, the state, the federal government and the PRPs. The group meets three to four times a year to discuss ongoing activities at the site. Although panel members routinely attend the meetings, there has been little outside public interest in Site activities in over five years.

An ad was placed in the local newspaper announcing the EPA’s proposal to modify the remedy for ground water and provided the date and time for a public meeting. The public meeting was held in the Nitro Community Center on October 10, 2006.

The public comment period concluded on October 30, 2006. EPA received one comment on the Proposed Plan and a response to this comment is provided in the Responsiveness Summary.

VI. SUMMARY OF THE AMENDED REMEDY AND PERFORMANCE STANDARDS

The amended remedy eliminates the 2001 OU4 ROD requirement to construct a pump and treat system for the contaminated groundwater. Those portions of the remedy for the Site, set forth in the 2001 OU4 ROD which are not addressed in this ROD Amendment, would remain in effect. The amended remedy requires the installation of a series of injection wells for air/peroxide/nutrients as well as the associated air delivery piping system. The key components

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of the remedy modifications are provided below:

Original Remedy Modified Remedy

Construct a wastewater treatment plant for contaminated ground water

Install a series of injection wells for air and peroxide/nutrients

Install extraction wells and associated piping Install an associated air delivery piping system

Develop and implement ground water monitoring plan

Develop and implement groundwater monitoring plan

Implement appropriate institutional controls to prevent consumption of contaminated ground water

Implement appropriate institutional controls to prevent consumption of contaminated ground water

Discharge treated groundwater in accordance with West Virginia NPDES program regulations and requirements

No discharge of ground water since water is treated in the subsurface

Pump and treat ground water until cleanup levels are achieved

Treat ground water until cleanup levels are achieved

The treatment system will consist of injection wells to reduce the concentration of contaminants of concern to health based clean-up levels. The locations and number of wells may change during the ongoing design process.

The preferred alternative for the Fike/Artel Superfund Site ground water is biosparging, with the addition of peroxide and/or nutrients, if necessary as determined by EPA (Alternative 3), and Monitored Natural Attenuation (Alternative 5) as a supplemental remedial technology — to reduce the concentration of contaminants in ground water to EPA’s Preliminary Remediation Goal of less than 1 x 10'5 cumulative excess cancer risk and a HI of less than 1.0. Institutional controls, to prevent the use of contaminated ground water, is a component of the preferred alternative.

Alternative 3 will be used to address the bulk of the ground water plume of dissolved COCs by installing a series of biosparging systems in phases. The first phase will be installed at the outer edge of the plume to prevent further migration of COCs in ground water. It is assumed that 50 biosparging injection devices will be installed for each phase. The injection devices will deliver air under pressure to the base of the alluvial aquifer.

If necessary, as determined by EPA, once aerobic conditions are created, periodic injections of biostimulants could be used to maintain or foster biodegradation of COCs. The system also

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could be enhanced with the use of in situ peroxidation for certain core regions of the plume.

Each phase would require the installation and operation of a dedicated, permanently sited air- compressor and control system and the associated air-delivery piping system.

Under this alternative, measures such as health advisories, West Virginia licensed well driller notification and/or membership to Miss Utility of West Virginia, or other institutional controls would be implemented to prevent exposure to contaminated ground water.

There are no known residential, commercial, or industrial uses of groundwater in the vicinity of the Site. Drinking water in the City of Nitro is obtained from the public water supply on the Elk River approximately 15 miles to the east. However institutional controls are warranted throughout the ground water plume, as currently depicted on Figure 2, to prevent consumption of the ground water until the clean-up levels are achieved.

Performance Standards

1. Ground water shall be sampled and analyzed for COCs prior to starting the in situ biosparging system to establish baseline conditions.

2. The in situ biosparging system shall introduce air into the subsurface at a rate such that monitoring shows a reduction in the concentration of COCs sufficient to achieve c leanup levels specified below within an estimated 20 year time frame.

3. The injection wells shall be constructed and operated in accordance with the Underground Injection Control (UIC) Program regulations.

4. The in situ biosparging treatment system performance shall be monitored to verify that the system is successfully reducing the concentration of COCs. The specific type, location and amount of monitoring shall be documented in a performance monitoring plan which shall be approved by EPA, in consultation with WVDEP.

5. Peroxide and/or nutrients shall be added to the treatment system to enhance the [reduction in concentration of VOCs] biosparging system if determined to be necessary by EPA, in consultation with WVDEP.

6. The system will continue to operate until the concentrations of COCs in ground water at the Site, identified below, are reduced to achieve the following acceptable risk-based cleanup levels when the concentration of COCs is considered cumulatively (same as 2001 ROD): a carcinogenic risk of 1 x 10'5 and a non-carcinogenic risk of Hazard Index of less than or equal to 1.0. In addition, for organic compounds, a requirement of this amended remedy is achievement of MCLs and non-zero MCLGs in the ground water, and for

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inorganic compounds, achievement of MCLs and non-zero MCLGs if these values are higher than the established background levels. If background levels are greater than MCLs or non-zero MCLGs, then the cleanup levels would default to background levels.

Cleanup levels must be met throughout the contaminated ground water plume. EPA has , estimated it will take 20 or more years to attain the cleanup levels.

The COCs are:

AldrinArsenicBenzenealpha-BHCBis (2-Chloroethyl) Ether (BCEE) bis (2-Chloroisopropyl) ether (BCIPE) bis (2-ethylhexyl) Phthalate (BCEP)Carbon Tetrachloride Chlorobenzene Chloroform 4,4-DDT1.2- Dichloroethane (1,2-DCA)1.2- Dichloropropane (1,2-DCP)1.3- Dimethyl-2-Thiourea (DMTU)HeptachlorHexamethyl Phosphoramide (HMPP)IronManganese Tetrachloroethene 1,1,2-Trichloroethane Trichloroethene Vinyl Chloride

7. Monitoring of ground water sufficient to measure cleanup progress shall continue until cleanup levels are achieved. A ground water monitoring and sampling plan will be developed for EPA’s approval. The performance of the treatment system shall be monitored through use of sufficient ground water-monitoring wells. Additional monitoring, wells shall be installed if EPA determines they are necessary. Monitoring of the ground water shall continue until ground water cleanup levels, as described above, are achieved. Monitoring of groundwater shall continue for a confirmatory period.

8. Institutional controls shall be implemented throughout the groundwater plume to prevent the consumption of ground water at the Site until cleanup levels are achieved. The

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groundwater plume is approximately identified on Figure 2.

VII. RESPONSIVENESS SUMMARY

EPA received one written comment on the Proposed Plan to modify the ground water remedy.

Question:

Based on a memorandum on the Discussion of Metals Fate and Transport prepared for the Fike Site and dated August 10, 2006, the party does not believe that arsenic, bis (2-ethylhexyl) phthalate, iron and manganese, among other compounds, should be considered Contaminants of Concern.

EPA Response:

EPA does not agree. Arsenic, iron, and manganese were detected in down gradient wells at concentrations greater than the background well (MW-200). The concentrations of these metals at several wells are greater than the risk-based concentration and in many cases the drinking water standard. EPA expects that by modifying the geochemistry of the groundwater by the addition of air that the concentrations of metals will be reduced through oxidation mechanisms. Thus, it is anticipated that the selected remedy will address both the chlorinated and inorganic contaminants of concern.

Bis (2-ethylhexyl) phthalate was not detected in the background well (MW-200). However, it was detected in several locations downgradient of the Fike property boundary, including at monitoring point DPT-217 at a concentration of 737 micrograms per liter.

VIII. AFFIRMATION OF THE STATUTORY DETERMINATIONS

EPA has determined that the Amendment described in this document will comply with the statutory requirements of CERCLA Section 121,42 U.S.G. § 9621. Considering the new information that has been developed and the changes to the selected remedy, EPA believes that the Amendment described in this document will remain protective of human health and the environment, comply with Federal and State requirements that are applicable or relevant and appropriate to this Remedial Action, as described in the OU4 ROD for this Site, and is cost effective. In addition, the Amendment described in this document utilizes permanent solutions

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and alternative treatment technologies to the maximum extent practicable for this Site.

Date ;s Burke, Director lazardous Site Cleanup Division

U.S. EPA Region III

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US EPA Region 3 OS Team 7/11/2006 M frank CCN1866 Map 3244

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