GROUNDWATER IN HOOSICK FALLS AND PETERSBURGH, NY; A SUMMARY OF PFAS DATA AND THE CURRENT STATUS OF NYS DEPARTMENT OF ENVIRONMENTAL CONSERVATION’S REMEDIAL ACTIVITIES

Per- and polyfluoroalkyl substances (PFAS) are a class of environmental contaminants which have recently been identified as a threat to human health and the environment. The U.S. Environmental Protection Agency (USEPA) has adopted a drinking water health advisory level for perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). The New York State Department of Environmental Conservation (NYSDEC) listed PFOA and PFOS as hazardous substances, which allows the State to use its legal authority to investigate and clean up impacted sites.

Specifically, in Eastern NY near the NY/VT border, use of PFOA as a part of the polytetrafluoroethylene (PTFE) dispersion coating processes at manufacturing facilities in Hoosick Falls and Petersburgh has led to widespread regional groundwater contamination. Multiple sites have been identified in the area that either released or received PFOA-containing waste, and are now being investigated by various parties under NYSDEC oversight. Several orogenic events followed by multiple stages of glacial advance and retreat during the Wisconsinan glaciation has resulted in complex and highly variable geologic conditions, which influence transport of contaminated groundwater in the region.

To characterize the nature and extent of PFAS contamination on a site-by-site and regional basis, the NYSDEC, USEPA, and the responsible parties have collected surface water, groundwater, sediment, and soil samples for chemical analyses. This presentation will focus on the spatial variability of PFOA and other PFAS in groundwater on a regional and site-specific basis. For the thousands of local environmental samples analyzed for PFOA to date, the maximum reported values are: 5,300 ng/L in surface water, 130,000 ng/L in groundwater, 110 µg/kg in soil and 160 µg/kg in sediment. Potential mechanisms driving the contamination of groundwater will be discussed as they relate to the release of PFAS pollution from these facilities; through the surface and subsurface from the disposal of liquid waste, atmospheric deposition tied to liquid dispersion coating operations and historical stack emissions, illegal dumping, and as a consequence of the various geologic controls that influence local and regional groundwater movement.