The group American Rivers hopes to shine a national spotlight on a proposed copper and nickel mine it says threatens Minnesota's Boundary Waters Canoe Area.
The group put the South Kawishiwi River, which flows into the BWCA, on its 2013 list of America's most endangered rivers. As the Duluth News Tribune reports, American Rivers says the mine near Ely would generate pollution that would then foul the waters of the country's most popular wilderness area.
A spokesman for Twin Metals, which is proposing the mine, tells MPR the state and federal governments have regulatory processes that include environmental safeguards. He sees American Rivers' designation as a call for pre-emptive rejection of the mine before that regulatory process has even begun.
The DNR's magazine, Minnesota Conservation Volunteer, took a look last summer at the mining issue and the promise and hazards it entails.
Geologists say the area near Ely is home to one of the three largest copper and nickel deposits on Earth. But those metals are in rocks that contain sulphide, which generates sulfuric acid when exposed to air or water.
American Rivers worries that acid will run off into the South Kawishiwi and wind up in the Boundary Waters. The News Tribune says Twin Metals has described plans to treat its wastewater and store waste rock undergound.
In its report, American Rivers also opposes a land swap that would turn part of the Superior National Forest over to the state. And it calls on Minnesota to stop auctioning mineral rights within the BWCA watershed.
The group's press release includes comments from business owners who say the area's water quality is central to its tourist economy.
Here's their list of the country's most endangered rivers.