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The Anacostia River is a freshwater tributary that flows through Maryland and the District of Columbia to the Potomac River. In D.C., the Anacostia River flows through National Park Service lands including the National Arboretum, Kenilworth Gardens, and Anacostia Park. The river has been the site of moderate oil spills, receives significant input of heavy metals and organic pollutants from urban nonpoint sources, and is known as one of the most polluted rivers in the United States. The sediments of the lower reach of this river have been found to contain elevated levels of polynuclear aromatic hydrocarbons PAHs, polychlorinated biphenyls PCBs, chlordane, chromium, lead, and zinc. High levels of PAHs were cited as a potential cause of the high incidence of carcinogenic tumors found in fish from the Anacostia River. The presence of injurious levels of toxic chemicals in the Anacostia Watershed places anadromous fish and endangered and threatened species such as the bald eagle at significant risk. In 1993, as part of a maintenance dredging action by the U.S. Army Corps of Engineers ACOE, dredged material from the Anacostia River was used to construct tidal freshwater wetlands in Kenilworth Marsh. This location was identified as the first of several sites along the main stem and side channels of the river where wetland restoration is proposed to enhance tidal mud flats using sediments from the Anacostia River. In this study, sediments, broadleaf cattails Typha latifolia, and killifish Fundulus sp. were collected and analyzed for PCBs, chlorinated pesticides, and metals. The objectives of this study were to determine the concentration of toxic chemicals present in the community developing on the new tidal freshwater wetlands in Kenilworth Marsh. Knowledge of transport and fate of the toxic constituents of wetland sediments will be used to substantiate an informed position on future use of dredged materials from the Anacostia River to construct wetlands.