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Pickettville Road Landfill
Pickettville Road Landfill Contact Information Scott M. Martin, Remedial Project Manager Site Repository: Documents:
The Pickettville Road Landfill site located in Duval County, Florida is a 52 acre site which began as a borrow pit for sand in the 1940's. From the 1960's until 1977 the site was backfilled with industrial and municipal waste. In the late 1970's and early 1980's the Florida Department of Environmental Regulation and the EPA documented the presence of volatile organic compounds and metals in site soil and groundwater. The site threatens local drinking water sources and two nearby creeks that receive site runoff from the site and discharge from the effected aquifers. The major contaminants include volatile organic compounds (VOCs) and metals in the soil and groundwater. Cleanup Progress: Construction Complete The objective of remedial action, as stated in the Record of Decision (ROD), was to address surficial soil contamination and waste materials at the site and to provide for the remediation of potential groundwater threats to the environment. Surficial soil/waste material problems will be rectified by establishing baseline conditions for comparison, minimizing the potential for direct exposure to the landfill material, limiting the potential for future indiscriminate dumping at the site, addressing the Florida Department of Environmental Protection (FDEP) statutory requirements for closure and post closure care of municipal landfills, and by assisting in the management of future leachate generation. Future groundwater threats will be remediated by establishing baseline conditions for comparison, minimizing hypothetical future exposure via consumption, and reducing the potential for future regional migration of groundwater constituents associated with the landfill. There is no active remediation technology being implemented at the Pickettville Road Landfill Superfund Site since the implementation of the Remedial Action (RA) and final acceptance of the RA Construction Report in 1997. The operation and maintenance simply consists of quarterly and semi-annual monitoring through the O&M period. Physical construction of the cap was completed in 1997, and groundwater samples were collected as part of performance monitoring. Analysis showed that metals and volatile organic compounds (VOCs) were present at unexpectedly elevated levels. EPA Region 4 began to consider an amendment to the Record of Decision to install an iron reactive permeable wall to treat the contaminants contained in the groundwater. While the amendment was being discussed, groundwater monitoring demonstrated that contaminant concentrations were decreasing. Additionally, although the remedy in the ROD called for groundwater monitoring, the data from the well network showed that natural attenuation was occurring (therefore achieving monitored natural attenuation as a result). Natural attenuation processes 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 soil or groundwater. These in-situ processes include biodegradation, dispersion, dilution, sorption, volatilization, and chemical or biological stabilization that cause transformation or destruction of contaminants. EPA Region 4 and the Florida Department of Environmental Protection (FDEP) agreed that natural attenuation was occurring and determined that the reactive wall was not necessary to treat VOCs. Groundwater monitoring has continued for more than ten-years, and, over this period, the VOC contaminant trend has demonstrated that the cap has been effective and that VOC contaminants have attenuated to below cleanup standards. Arsenic concentrations remained above cleanup standards in two groundwater wells. During this period, FDEP expressed concern that the groundwater to surface water pathway had not been adequately characterized, and that groundwater contaminant concentrations adjacent to the streams were unacceptable if compared to surface water standards. EPA Region 4 undertook an effort to substantiate the apparent attenuation of arsenic in groundwater and to better characterize the groundwater to surface water pathway. Evaluation of the groundwater monitoring well network data demonstrated that natural attenuation of the contaminant would achieve the remedial action objectives. Region 4 also performed pore-water sampling of the adjacent streams and the results were received in September 2008. These results showed that groundwater contaminants pose no potentially unacceptable risks to human or ecological receptors who may be exposed to the adjacent surface water bodies. For these reasons, no further remedial construction is warranted or anticipated at this site, and the construction completion milestone was achieved September 24, 2008. Five-Year Review
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