Benthic invertebrates were collected from Trout Creek, Fish Creek, and the Williams Fork (tributaries of the Yampa River in Routt and Moffat Counties), and Little Grizzly and Grizzly Creeks (tributaries of the North Platte River in Jackson County). Stream-sampling sites were upstream and downstream from potential, existing, or historical coal-mining areas. Field water-quality measurements of water temperature, specific conductance, pH, and dissolved oxygen were also made to aid in assessing stream water-quality conditions. The purpose of the study was to describe and quantify the benthic invertebrate communities in selected streams in coal-mining areas. Sampling was conducted on a near bimonthly basis throughout the growing season, beginning in April and May 1980, and continuing through September 1981. This report describes the methods of data collection and presents qualitative and quantitative results of benthic invertebrates and associated water-quality data. (USGS)