New Cassel/Hicksville Ground Water Contamination Site Listed on NYSDEC Inactive Hazardous Waste Site Registry

Environmental Law


On June 18, 2013, the New York State Department of Environmental Conservation (“NYSDEC”) added the New Cassel/Hicksville Ground Water Contamination Site (the “Site”) to its Registry of Inactive Hazardous Waste Disposal Sites. The Site was classified as a Class 2 site because it presents a significant threat to public health and the environment. The Site was first listed by the United States Environmental Protection Agency (“EPA”) on its National Priorities List (“NPL”) in 2011. New York State Environmental Conservation Law § 27-1301(2) requires NYSDEC to list all NPL sites within the state on its Registry.

The New Cassel/Hicksville Ground Water Contamination Site is located within the Towns of Hempstead, North Hempstead, and Oyster Bay, Nassau County, New York and involves volatile organic compound (“VOC”) contamination of the groundwater. The primary contaminants of concern in the underlying aquifer are tetrachloroethene (“PCE”) and trichloroethene (“TCE”) which are chemicals used in paints, solvents, cleaners, automotive products, and dry cleaning fluids. The presence of these VOCs in the groundwater is a result of waste discharges by multiple current and past industrial and commercial facilities located in the vast area of Nassau County that makes up the Site.

The major concern is to the public health because the groundwater underlying the Site is the sole source aquifer for the public water supply. Several of the local public supply wells have been found to have TCE and PCE concentrations above the Maximum Contaminant Level (“MCL”). Water is being treated by engineered controls to remove contaminants prior to distribution to the public, however, a significant threat to public health remains due to the potential for contaminants in the groundwater to reach public supply wells that do not have the necessary treatment systems in place.

Currently, EPA and NYSDEC are working in concert to monitor and investigate the Site. EPA is reviewing and analyzing data generated from the monitoring of the public supply wells and formulating a comprehensive strategy for future investigation and remediation. NYSDEC continues to monitor and maintain all activities currently in place. Property owners adjacent to the Site or renting or leasing property near the Site should be aware of this classification and ensure their drinking water is being treated. Further, current and past owners and operators of industrial and commercial facilities within the Site area that have used, stored, or disposed of VOCs should keep abreast of the investigation and the status of steps being taken by the government agencies, which are likely to seek out potentially responsible parties to undertake and/or fund the investigation and remediation of the Site.

For more information on this Site and on groundwater contamination and inactive hazardous waste site classification, please contact Miriam Villani or Jason Kaplan.

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