In 2004, the USGS, in cooperation with the EPA, established a water-quality monitoring network totaling 18 sites from Mullan to Post Falls, Idaho. USGS hydrologist Greg Clark analyzed water-quality data collected from October 2009 through September 2013. Clark also examined data dating back to the early 1990s to look for any long-term trends.
Read the news release.
Read more about the study.
In this report, hdyrologist Greg Clark analyzes water-quality data that the USGS has collected on behalf of the Environmental Protection Agency in and around the Bunker Hill Superfund site in northern Idaho. The data show that concentrations of three trace metals of concern—cadmium, lead, and zinc—have declined significantly since the 1990s.
USGS and Idaho Department of Environmental Quality scientists combined and analyzed data sets from two separate water-quality monitoring efforts in the upper Blackfoot River basin in southeastern Idaho. Naturally occuring selenium washed into the river from phosphate mines has raised concerns about possible impacts to fish and other aquatic life forms in the basin, as well as grazing livestock.