Spence Farm sits in Plumstead Township, Ocean County, New Jersey. It operated as an agricultural and woodland area before being used as a hazardous waste dump from 1961 to 1967. The New Jersey Department of Environmental Protection flagged it as a hazardous waste site in 1980, and EPA added it to the National Priorities List in September 1983. The site is also known as the Thiokol Corp Site.
Contamination spreads across several media. Groundwater holds arsenic, chromium, mercury, zinc, dichloromethane, bis(2-ethylhexyl)phthalate, di-n-octyl phthalate, and phenol. Soil contains dichloromethane along with inorganic and organic substances. Sediment and surface water carry dichloromethane, mercury, and zinc. Solid waste contains 2,4-dichlorophenol. Polychlorinated biphenyl (PCB) contamination was also found in soil during follow-up sampling after the initial cleanup.
Morton International, the company responsible for the contamination, carried out the cleanup work. Crews removed all drums and laboratory wastes, excavated contaminated soil, and disposed of roughly 4,360 cubic yards of waste material and contaminated soil at approved facilities between 1982 and 1994. Additional soil removal addressed the residual PCB contamination found after that first round of work. Groundwater sampling over five years following cleanup showed the groundwater is clean. The selected remedy for the single operable unit covering the entire site included monitoring, slope stabilization, excavation, and onsite containment.
Construction finished in February 1996, and EPA deleted the site from the National Priorities List in March 1997 after confirming all necessary cleanup actions were complete. Human exposure is under control, with no unacceptable exposure pathways present. Contaminated groundwater migration is stabilized, and there is no unacceptable discharge to surface water. EPA continues monitoring to confirm affected groundwater stays within the original contamination area. The site reached sitewide ready for anticipated use status in June 2006, meaning all cleanup goals for current and future land uses have been met and all required land-use controls are in place. Most of the site is now used for farming, with some woodland remaining in less accessible areas.
Community members with questions can contact the EPA team overseeing the site. Documents and reports related to Superfund work at this site can be reviewed in person at the EPA Superfund Records Center, 290 Broadway, 18th floor, New York, NY 10007.
