PolyMet Mine, Minnesota

Minnesota River

A foreign corporation, PolyMet Mining, Inc., is proposing to develop the first sulfide mine in Minnesota. The PolyMet mine would be an open pit copper and nickel mine north of Hoyt Lakes in the Superior National Forest. It is likely to be the first of many sulfide mining proposals in northern Minnesota. Other companies are exploring mineral deposits north of Lake Mille Lacs to the edge of the Boundary Waters Canoe Area Wilderness near Ely.

Impacts to Communities & Wildlife

Unlike iron mines, sulfide mines release sulfuric acid when water comes into contact with tailings and other mine wastes. In places where this type of mining is common, acid mine drainage has a long and tragic history of contaminating rivers, lakes, and groundwater. The PolyMet mine regulations will set a precedent that could govern sulfide mines in Minnesota for years to come. EPA is forcing PolyMet to supplement its environmental analysis, but current plans call for the following:

  • Three open pits of 800 acres producing an estimated 394 million tons of waste rock and ore, all generating acid

  • Transport of the ore to a mill located at the former LTV Steel Mining Company taconite processing plant.

  • Millions of tons of mine tailings discharged in the form of a toxic, semi-solid slurry into the existing LTV tailings reservoir, which is unlined and contains wetlands and ponds.

  • Destruction of approximately 1,000 acres of wetlands, indirect impacts upon 500 acres of wetlands

Mining Tailings and Clean Water Don't Mix

River Otter

The PolyMet mine is an example of why mine waste should not be discharged into water bodies. The existing taconite tailings, which were dumped onto the wetlands and streams within the tailings impoundment, are already leaking through numerous surface seeps and possibly groundwater flow. These point sources have contributed to elevated levels of pollutants in the Lake Superior watershed.

There is no single solution to the problems posed by sulfide mining, but one obvious step is to stop mines from dumping their toxic wastes into lakes, rivers, and wetlands. Aquatic ecosystems are among our most valuable community and wildlife resources, but they are also natural conduits that can transport pollution for miles if a mining waste impoundment is improperly built, fails, or deteriorates with age.

We Can Close the Mining Loopholes

As a nation, we decided that industries should not be able to profit from polluting the waters that sustain America's communities, fish, and wildlife. Help us close the two loopholes in the Clean Water Act that encourage irresponsible mining practices and irresponsible mines such as the PolyMet mine in Minnesota.

Action Button

Urge the EPA and Army Corps to protect our nation's waters and wildlife by closing the mining loopholes in the Clean Water Act. >>

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