Hazardous wastes at Superfund sites are found in a number of media, including groundwater, surface water, soil, and sediment. The unique properties of each media and their varied reactivity with contaminants require that each cleanup take into account the specific nature of the polluted site. In order to better understand and identify appropriate methods for cleaning up polluted media at Superfund sites, SBRP researchers are working to elucidate the mechanisms involved in media contamination; identify remediation techniques most suitable for specific media; and identify resulting health effects of media contamination on humans and the surrounding ecology.