Our team studies landfill leachate biogeochemistry and the natural attenuation of contaminants in leachate plumes. We are studying landfills across the United States as part of the first national scale assessment of emerging contaminants in landfill leachate. Extensive investigations into biogeochemical processes controlling leachate migration have been conducted at the Norman, OK, closed landfill. Our objectives include providing a comprehensive characterization of Emerging Contaminants (ECs), geochemistry, and microorganisms in fresh leachate and leachate being discharged off-site to Waste Water Treatment Plants,(WWTP), streams, and groundwater in order to assess the potential importance of landfills as a source of contaminants. Results serve as a biological and chemical baseline for landfill leachate in the United States and will provide insight on the development of leachate plumes. Our results also provide an understanding of the contribution of landfill-derived ECs being released to WWTPs, surface water, or groundwater. Because many landfills discharge to a WWTP, our results will help determine whether the disposal of pharmaceuticals via the trash input ultimately results in a pathway to the environment. Fresh leachate has been studied at 19 non-hazardous landfills across 16 states, representing a range of landfill sizes, ages, composition, geographic regions, and climates. This study is part of the Emerging Contaminants Project.