Assessed the distribution, sources, and transport mechanisms of chlorofluorocarbons (e.g., Freon), chlorinated solvents, and gasoline antiknock chemicals into the Delaware River (river sediment and surface water), and in an aquifer beneath the Delaware River. Analyzed data collected over 2.5 miles of coastline, including results of dual frequency echo-sounder for bathymetric mapping, side-scan sonar to map sediment types, vibratory coring to map lithology of sediment and depth to an underlying aquifer, and push-probe and grab confirmatory sampling of sediment. Temporary wells were advanced beneath the riverbed to collect groundwater samples. Identified aquifer subcrop and DNAPL beneath the river, and calculated plume mass flux discharge to the river.