Abstract |
Most chemical contaminants and organic wastes in aquatic ecosystems eventually accumulate in sediments where they may adversely affect the benthic biota, become a source of contamination in the water column, accumulate in biological tissues, and enter pelagic and human food chains. Contaminated sediments now appear to be the main source of toxic pollutants in many bays, lakes, and rivers. Because of their potential adverse impacts, the long periods of time associated with natural assimilation of many in-place pollutants, and the high costs of mitigation, sediments have become a focus of concern for many of EPA's research and regulatory programs. Programs in which sediment quality assessments are currently required include ocean dumping, NEPA review, Superfund, and estuarine protection. The documents addresses regulatory applications, current and future sediment quality criteria needs, and both chemical specific and nonchemical specific sediment quality evaluations. Mitigation/prevention of sediment quality problems are identified and five kinds of predictive methods are suggested, as well as future research to develop more sensitive testing capabilities. |