Occurrence and source identification of perfluoroalkyl acids (PFAAs) in the Metedeconk River Watershed, New Jersey

The Brick Township Municipal Utilities Authority (BTMUA), which relies on the Metedeconk River as its primary source of water supply, initiated a perfluoroalkyl acid (PFAA) source trackdown study in collaboration with the New Jersey Department of Environmental Protection (NJDEP) after discovering that the concentration of one PFAA, perfluorooctanoic acid (PFOA), was elevated at their raw surface water intake. Water samples were collected over eight sampling events between September 2011 and July 2014. Samples included surface water, groundwater, stormwater, sanitary sewer water, and commercial/industrial process water. Each sample was analyzed for ten PFAAs. Results from a set of samples collected from the 80 km² South Branch Metedeconk River watershed directed the focus of this study to a 7.5-km² area of interest. Within this area, a high concentration of PFAA contamination was documented in a localized zone. Subsequent groundwater sampling led to the identification of a plume of groundwater contamination emanating from an industrial/business park. The suspected source of PFAA detected in the river and drinking water intake was identified to a small industrial facility that used materials containing PFOA. Groundwater PFOA concentrations as high as 70,000 ng/L were found in samples taken within 200 m of the parcel and surface water concentrations as high as 130 ng/L were observed in the river. While various PFAAs were detected in the samples, particularly in groundwater samples, PFOA was identified as the primary contaminant of concern with respect to the river and the BTMUA water supply.