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Arsenic data for streams in the uppper Missouri River Basin, Montana and Wyoming

J. R. Knapton·A.A. Horpestad
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Abstract

Although large concentrations of arsenic originating from geothermal sources within Yellowstone National Park have been known to be present in the Madison River for many years, systematic monitoring throughout the upper Missouri River basin had not been done. Therefore, a monitoring network consisting of 24 stations was established for the purpose of measuring arsenic concentrations and determining arsenic discharge. Included were 5 sites on mainstems of the Madison and Missouri Rivers and 19 sites on major and some minor tributaries from Yellowstone National Park to Canyon Ferry Lake. Fifteen of the 24 stations were sampled 12 times from November 1985 to October 1986. The remaining stations were sampled twice during the year, at high flow and at low flow. Total recoverable arsenic discharge (loading) in pounds per day was calculated for each sample by multiplying total recoverable arsenic concentration by water discharge (obtained at time of sample collection) and a conversion factor. This report presents data resulting from the monitoring program. (USGS)

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J. R. Knapton, A.A. Horpestad. 1987. Arsenic data for streams in the uppper Missouri River Basin, Montana and Wyoming. https://doi.org/10.3133/ofr87124

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