The 400-acre Cinnaminson Groundwater Contamination site is in the townships of Cinnaminson and Delran, Burlington County, New Jersey. The site overlies a deep aquifer and a shallow aquifer, and the latter is a potential source of drinking water. Furthermore, the site lies within the Delaware River floodplain. From 1950 to 1980, municipal solid waste and other refuse were deposited in the mining pits, while mining operations continued in other site areas. In 1970, Sanitary Landfill Inc. (SLI) operated an onsite sanitary landfill in the same area, which accepted hazardous industrial waste. In 1980, the State identified improper waste disposal practices onsite, and ordered SLI to close the landfill. In 1981 as part of the closure plan, SLI capped the landfill with 18 inches of clay, installed a gas collection and venting system, and initiated ground water monitoring. Subsequent ground water studies by EPA and SLI identified onsite ground water contamination in the landfill area. Additionally, various onsite industrial operations and local area septic systems were also identified as potential sources of ground water contamination. The Record of Decision (ROD) addresses remediation of onsite contaminated ground water in the shallow and deep aquifers, and prevention of further migration of contamination into municipal wells. The primary contaminants of concern affecting the ground water are VOCs including benzene, PCE, TCE, toluene, and xylenes; other organics including PAHs and phenols; and metals including arsenic, chromium, and lead.