Publications

Georgetown Lake is a recreational reservoir located in the upper Clear Creek Basin, a designated Superfund site because of extensive metal mining in the past. Metals concentrations in Clear Creek increase as the stream receives runoff from mining-affected areas. In 1997, the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, began a study to determine...

Forty-four river, stream, and drain sites in the Upper Colorado River Basin in Colorado were sampled during 1996?98 to determine the occurrence and distribution of pesticides in the basin. In a fixed-station study, 57 surface-water samples were collected from October 1996 through January 1998 at four sites. Each site was sampled approximately monthly for up to a year, with more frequent...

Regionalized flood-frequency relations need to be updated on a regular basis (about every 10 years). The latest study on regionalized flood-frequency equations for Colorado used data collected through water year 1981. A study was begun in 1994 by the U.S. Geological Survey, in cooperation with the Colorado Department of Transportation and the Bureau of Land Management, to include...

No abstract available.

Acid mine drainage from abandoned and inactive mines affects the water quality of the upper reaches of Fisher Creek, Montana. A sodium chloride tracer was added to the stream for 29.5 hours to provide a hydrologic context for synoptic sampling of metal chemistry in the stream and its inflows. The detailed profile of stream discharge obtained from the sampling helped to indicate those...

No abstract available.

Snowmobile use in Yellowstone National Park has increased substantially in the past three decades. In areas of greatest snowmobile use, elevated levels of by-products of gasoline combustion such as ammonium and benzene have been detected in snowpack samples. Annual snowpacks and snow-covered roadways trap deposition from local and regional atmospheric emissions. Snowpack samples...

The relative abundance of minerals that react to generate or consume acid in mineralized areas is critical in determining the quality of water draining from such areas. This work examines the fundamental reactions that influence the pH and composition of drainage from mine adits and tailings piles. We construct triangle diagrams that predict stoichiometric relationships between...

Biological community samples were collected at 15 sites in the Upper Colorado River Basin (UCOL) in Colorado as part of the National Water-Quality Assessment (NAWQA) Program. Sites sampled in two physiographic provinces, the Southern Rocky Mountains and the Colorado Plateau, represented agriculture, mining, urban and recreation, and mixed land uses and background conditions. Nine...

No abstract available.

In March 1994, the Colorado Division of Water Resources (CDWR) adopted ?Rules Governing the Measurement of Tributary Ground Water Diversions Located in the Arkansas River Basin? (Office of the State Engineer, 1994); these initial rules were amended in February 1996 (Office of the State Engineer, 1996). The amended rules require users of wells that divert tributary ground water to...

Stream water data from five headwater basins in the northeastern United States covering water years 1968–1996 and precipitation data from eight nearby precipitation monitoring sites covering water years 1984‐1996 were analyzed for temporal trends in chemistry using the nonparametric seasonal Kendall test. Concentrations of SO4declined at three of five streams during 1968–1996 (p 0.1)...