http://www.spokesman.com/ [Spokane, Washington]
Cleaning up historic mine waste is paying dividends for water quality in the Coeur d’Alene River Basin, according to a new report published by the U.S. Geological Survey.
The report looked at two decades of water quality monitoring for the Coeur d’Alene River and its tributaries. Since the early 1990s, concentrations of lead, cadmium and zinc have dropped by 65 percent in the South Fork of the Coeur d’Alene River near Pinehurst, Idaho.
Other streams also showed water quality improvements, though most continue to exceed safe limits for heavy metals.
In addition, large amounts of mining waste continue to wash down the Coeur d’Alene River and into Lake Coeur d’Alene, the report said. About 400 tons of lead, 700 tons of zinc and 5 tons of cadmium flow into the lake each year, according to data collected from 2009 through 2013. Most of the metals settle at the bottom of the lake, with some flowing out of the lake and into the Spokane River.
Overall, the report is “good news for the people of the basin,” Rick Albright, the U.S. Environmental Protection Agency’s Superfund cleanup director in Seattle, said in a statement. “We still have a long way to go in our cleanup efforts, but it’s nice to have scientific confirmation that we’ve made solid, measurable progress in reducing metals loads and improving area water quality.”