9421491 Brooks This is an award to support research, the objective of which is to obtain an understanding of the fundamental physical and chemical processes that control the interchange of substances in alluvial sediments of flowing water streams with the water as affected by the sediment bed forms such as ripples and dunes. The basic approach being taken in this research is the conduct of experiments in recirculating laboratory flumes under very carefully controlled conditions of flow, water quality, the bed media and the nature of the substances dissolved or in particulate form being exchanged at the bed-fluid interface. This is a renewal of research previously conducted under NSF Grant No. 91-05965. Results of this research may be applied to answering important questions relating to the pollutional effects that substances in bottom sediments of water bodies have on the overlying water quality. This knowledge is likely to be applied in environmental engineering practice to determine approaches to removal of potential water pollutants and contaminants from sediments and in determining locations for wastewater treatment plants that would minimize the undesirable effects on environmental quality of their effluent discharges and management practices for residual sludges. ***
