Urban Stormwater Inputs of Perfluorochemicals

Project summary:

Perfluorochemicals (PFCs) have been used in a variety of industrial polymers and commercial products, from Teflon to Scotchgard. Despite the phaseout of these chemicals from production, they continue to cause concern regarding environmental and human health. In 2007, several Twin Cities metropolitan lakes were labeled "impaired for contamination" with a suite of perfluorochemicals, primarily perfluorooctane sulfonate (PFOS) in fish. While Minnesota is home to the 3M corporation, which produced and disposed of many of these chemicals, many of the lakes listed as impaired have no connection to 3M's production or disposal. Because many of these PFCs were used in commercial products, wastewater is another potential source of contamination, however, none of these lakes receives direct wastewater discharge. We hypothesize that a significant source of PFC contamination to surface waters is urban stormwater, which receives PFCs from commercial, industrial, and residential sources within its watershed. The goal of this project is to sample temporal composites of urban stormwater integrated over storm events and to analyze them for a suite of PFCs. These PFC concentrations will then be combined with detailed land-use information for the watershed and will be used to model the source apportionment of PFCs to urban stormwater. The objectives of this study are to (1) quantify the magnitude of PFC loadings from urban stormwater; (2) identify unique land-use characteristics that lead to PFC contamination; and (3) determine the efficacy of suspended sediment removal as a technique for removing PFCs from stormwater.