NEW YORK, NY, Aug. 12, 2014 -- The Environmental Protection Agency (EPA) has determined that no further action is needed to address the capping of two closed landfills at the Cinnaminson Groundwater Contamination Superfund site in the townships of Cinnaminson and Delran, N.J.
No further actions with respect to the capping of the landfills are needed because the actions already taken are effective. The EPA reviewed conditions at the site and has determined that the threat of further release of contaminants from the landfills to the groundwater has been addressed. Groundwater monitoring conducted over the past 26 years confirms the effectiveness of the previous capping of the landfills.
The site, which covers approximately 400 acres, includes residential and industrial properties and the two landfills. As a result of historic operations throughout the site, the groundwater and soil were contaminated with volatile organic compounds and heavy metals, which can have serious health effects. The EPA will require that the groundwater associated with the landfills continues to be monitored and treated, if necessary.
To date, the landfills have been covered with protective caps to prevent water from flowing through them, and a system has been constructed to collect gas generated from the landfills. In addition, contaminated groundwater in the area had been pumped and then treated to prevent contaminants from spreading. An assessment regarding the continued operation of the groundwater extraction and treatment system is ongoing. The local drinking water supply is monitored regularly to ensure that water meets drinking water standards and is safe to consume, which it currently is.
The landfill property on the site was originally a sand and gravel mining operation. Later, solid waste including hazardous substances were dumped in the mining pits. Sanitary Landfill, Inc. operated the landfills from 1970 until they closed in the 1980s. The site was first addressed by the New Jersey Department of Environmental Protection, with the EPA taking over when the site was added to the federal Superfund list in 1986.
The EPA's remediation of the site has been conducted in phases to facilitate the long-term restoration of the area. In 1987, Sanitary Landfill covered the landfills with a clay cap to keep water from mixing with the contaminants and spreading the groundwater contamination. A landfill gas management system to collect and control landfill gas was expanded in 1996.
In the first phase of the EPA cleanup in 2000, SC Holdings, Inc., successor to Sanitary Landfill, constructed a groundwater extraction and treatment system to clean the polluted groundwater and installed wells to measure and monitor groundwater contamination. The groundwater monitoring for volatile organic compounds and metals is ongoing and performed twice a year.
In the second phase of the project, announced on Wednesday, Aug. 6, SC Holdings will continue to monitor the groundwater and the landfill caps to ensure that people's health and the environment are protected. The landfill caps are working well, and the EPA will continue to monitor the site and can require more actions if site conditions should change. The EPA is currently assessing the need for continued operation of the groundwater extraction and treatment system.
The third and fourth phases of the cleanup will address soil and groundwater contamination in other areas of the site.