314 - Influence of Historic and Current Land Use Practices on PCB Contamination of Soils and Stormwater Sediments in the Chesapeake Bay Watershed

Polychlorinated biphenyls (PCBs) are a group of chlorinated compounds derived from biphenyl which are classified as persistent organic pollutants (POPs). PCBs were banned in 1976 by the Toxic Substance Control Act in the United States but still can be found in numerous water bodies. Total Maximum Daily Loads (TMDLs) have been developed in many cases. Local soils and roadway sediments may be mobilized in stormwater and may contain attached PCBs. Soils and sediments have been collected from different sites in Maryland, with different land uses and eras of development. Concentrations of 209 PCB congeners are determined and analyzed in these soils and sediments samples by gas chromatography/electron capture detector. Non-legacy PCB 11 has been the most frequently detected congener in stormwater sediments and soils and has been found in yellow road paints. Sediment PCB concentrations will be correlated to land use and era of development. It is expected that industrial land uses and pre-1979 developments will have the highest PCB contaminated soils and sediments, relative to residential land uses and post 2005 developments. Information on PCB concentrations in sediments from different land uses can be used as an estimation of PCB load removal in various stormwater controls. Stormwater control measures can be targeted to land uses with the highest sediment PCB concentrations.