This report summarizes a portion of the research done under Grant GI-32990 from the RANN Program of the National Science Foundation. The research is a continuation of the development and application of models of agricultural production, resource use, and the environment. Previous research concentrated on the use of resources in agriculture and the development of models to determine the levels of potential environmental harm. This extension links the resource utilization and residue-creating production activities of cropland agriculture to the quality of water in the nation's streams. The polluting substance studied is sediment.