Declaration Statement, Record of Decision
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SDMS Document 99365 DECLARATION STATEMENT RECORD OF DECISION Vineland Chemical Company Site Name and Location Vineland Chemical Company, Vineland, Cumberland County, New Jersey Statement of Basis and Purpose This decision document presents the selected remedial action for the Vineland Chemical Company site, developed in accordance with the Comprehensive Environmental Response, Compensation and Liability Act, as amended by the Superfund Amendments and Reauthorization Act and, to the extent applicable, the National Contingency Plan. This decision is based on the administrative record file for this site. The State of New Jersey has concurred with the selected remedy. Assessment of the Site Actual or threatened releases of hazardous substances from the site, if not addressed by implementing the response actions selected in this Record of Decision, may present an existing or potential threat to public health, welfare, or the environment. Description of Selected Remedy The remedial actions selected in this document represent permanent solutions for three portions of the site including the contaminated plant site soil, the contaminated groundwater in the underlying aquifer, and the exposed and subaerged contaminated sediments in Blackwater Branch and the Maurice River. In addition, an interim remedy is presented for the fourth portion, which addresses the contaminated sediments in Union Lake. The remedial actions, which will be implemented in phases or operable units, consist of the following: 1 Operable Unit One (Plant Site Source Control) 0 In situ treatment, by flushing, of the arsenic-contaminated soils to reduce arsenic levels. Portions of the contaminated soil will be excavated and consolidated prior- .^ to the flushing action. *^ 5c=? 0) ~on o Plant site remediation also includes closure of the two lined surface impoundments in compliance with the Resource Conservation and Recovery Act (RCRA), and decontaaination of the former chicken coop storage buildings. Operable Unit Two (Plant Site Management of Migration) o Removal of arsenic-contaminated groundwater through pumping, followed by on-site treatment and reinjection of the treated groundwater to the aquifer at the maximum rate practicable. The remainder of the treated groundwater will be discharged to the Maurice River. A portion of the treated groundwater will also be used for the soil flushing action in Operable Unit One. The arsenic-contaminated sludge from the groundwater treatment process will be transported off-site for hazardous waste treatment and disposal. This action will effectively eliminate the source of arsenic into the Maurice River system. Operable Unit Three (River Areas Sediments) o Excavation and treatment of the exposed arsenic-contaminated sediments in the Blackwater Branch floodplain. Treatment will consist of a water wash extraction. The cleaned sediments will be redeposited in the excavated portion of the floodplain. The sludge from the extraction process will be transported off-site for hazardous waste treatment and disposal. Remediation will begin after the contaminated groundwater flow into the Blackwater Branch has been stopped. o Dredging/removal and treatment, by water wash extraction, of the submerged arsenic-contaminated sediments in the Blackwater Branch adjacent to and downstream of the Vineland Chemical Company plant site. Prior to removing any sediments, an environmental assessment of the impact of dredging will be performed and a confirmation made that these sediments are a source of contamination to the river system. The treated sediments will be redeposited on undeveloped areas of the Vineland Chemical Company plant site. The sludge from the extraction process will be transported off-site for hazardous waste treatment and disposal. o After stopping the flow of arsenic-contaminated groundwater from the Vineland Chemical Company plant site, a three year period for natural river flushing will be implemented. This will allow the submerged, arsenic-contaminated sediments in the Maurice River to be flushed clean through natural processes. If, after this period, the submerged sediments are no longer contaminated with arsenic above the action level, no remediation will be performed in the river. Similarly, if sediment contamination above the action level persists, but the observed or expected natural decontamination rate is consistent with an acceptable public health risk, no remediation will be performed. However, if contamination above the action level persists in some locations and is expected to remain at levels posing unacceptable health risks, those locations would be remediated. o Remediation of the submerged Maurice River sediments will be performed, as necessary, by dredging and treatment with a water wash extraction. However, prior to removing any sediments, an environmental assessment of the impacts of dredging will be made. The treated sediments will be deposited on undeveloped areas of the Vineland Chemical Company plant site. The sludge from the extraction process will be transported off-site for hazardous waste treatment and disposal. Operable Unit Four (Union Lake Sediments) o Removal and treatment of arsenic-contaminated sediments on the periphery of Union Lake will be performed after the three year flushing period (if no remediation is performed in the Maurice River) or after remediation of the Maurice River (if this is necessary following the flushing period). Verification sampling will be conducted prior to remediation to confirm the locations of sediments contaminated above the action level for arsenic along the periphery of Union Lake. o The arsenic-contaminated sediments on the periphery of Union Lake will be excavated after they are exposed by lowering the lake's water level. However, for the upper end of the lake above the submerged dam, prior to removing any sediments, an environmental assessment of the impact of dredging will be performed. The sediments will be treated by water wash extraction and the cleaned sediments returned to their approximate former locations in Union Lake. The sludge from the extraction process will be transported off-site for hazardous waste treatment and disposal. o This is an interim remedy, since arsenic-contaminated sediments above health-based levels will remain in Union Lake. Therefore, periodic reviews will be conducted to determine whether contaminated sediments are redistributed, through natural processes, to the cleaned areas. H Statutory Determinations The selected remedies for Operable Units One, Two and Three are protective of human health and the environment, comply with Federal and State requirements that are legally applicable or relevant and appropriate to these remedial actions, and are cost-effective. These remedies utilize permanent solutions and alternative treatment technologies to the maximum extent practicable and satisfy the statutory preference for remedies that employ treatment that reduces toxicity, mobility, or volume as a principal element. Because these remedies will not result in hazardous substances remaining on-site above health-based levels, the five year review will not apply to these actions. The selected remedy for Operable Unit Four is an interim remedy which protects human health and provides for further monitoring and study to determine the scope and nature of any additional actions which may be necessary. The supplemental study will address the dynamics of sediment transport to, within, and from Union Lake, and will deal with the effect of arsenic on biota. This interim remedy will meet all of the statutory preference criteria, with the exception of permanence. Because the remedy for Operable Unit Four will result in hazardous substances remaining in Union Lake above health-based levels, a review will be conducted within five years after commencement of remedial action at the lake to ensure that the remedy continues to provide adequate protection of human health and the environment. William Jx^MuszyJci , P.E. 'bate Acting Regional Administrator O O DECISION SUMMARY Vineland Chemical Company Site Vineland, New Jersey SITE DESCRIPTION The Vineland Chemical Company plant site is located in a residential/industrial area in the northwest corner of the City of Vineland in Cumberland County, New Jersey. The plant location is shown in Figure 1. The Vineland Chemical Company has produced organic herbicides and fungicides at this location since 1949. The herbicide manufacturing process reportedly has produced approximately 1,107 tons of waste by-product salts each year. These wastes have an Environmental Protection Agency (EPA) hazardous waste number of K 031 and are presently neither treated nor disposed of at the site, and are not stored on-site for more than 90 days. The salts are transported by licensed shippers to licensed facilities in Ohio and Michigan for disposal. In the past, improper storage of these salts on the plant property led to arsenic contamination in the soil and groundwater. The Vineland Chemical Company site is ranked among the top ten hazardous waste sites in New Jersey, and is ranked number 42 on the National Priorities List. Arsenic contamination, attributable to the Vineland Chemical Company, has been detected in the soils and groundwater at the plant site, and has been detected in surface waters and sediments as far as 36 miles downstream from the plant. The plant site is shown in Figure 2. The plant consists of several manufacturing and storage buildings, a laboratory, a worker change facility, a wastewater treatment plant