Sulfide mining in Minnesota

Several mining companies have set their sights on northeastern Minnesota.They include the PolyMet proposal, which is the furthest along of any company, and over 100 recent applications to explore for minerals on public lands, much of which is just outside the Boundary Waters Canoe Area Wilderness.


PolyMet Mining Inc. proposes to construct and operate an open pit mine and processing facility—called the “NorthMet Project”—to extract metals from sulfide ores. The company seeks primarily copper, nickel, platinum and palladium.

The mine and processing facility would be between Hoyt Lakes and Babbitt, Minnesota. This area is within the Partridge River watershed, which drains into the St. Louis River and then into Lake Superior.

PolyMet’s proposal is the farthest along of any sulfide mining proposal in the state. In November 2009, the Draft Environmental Impact Statement analyzing this project was released. It is available for public review and comment until February 3, 2010.

Some facts about the PolyMet project:

  • The proposed mine site is on public land in the Superior National Forest
  • The project would excavate 91,200 tons per day of rock, generating approximately 394 million tons of waste rock over the life of the mine
  • The project would create three open pits ranging in size from 54 to 278 acres in size, and up to 840 feet deep.
  • At least 1,500 acres of wetlands would be impacted by the project.
  • Reactive waste rock piles would be permanently left on the land – ranging in size from 70 to 560 acres in size, and from 13 to 20 stories high.
  • The project proposes to store mine tailings and toxic waste materials in an existing mine tailings basin that has current basin stability problems.

Learn more about PolyMet and submit your own comments to the DNR on the project’s Draft Environmental Impact Statement. The state needs to hear from all Minnesota citizens!

Arrowhead region sulfide mining activities

Franconia, Duluth Metals and other exploration – on the BWCAW’s door step

Northeast of PolyMet’s proposed mine site, other companies are exploring sulfide ore deposits and crafting their own proposals for mines. All of these activities are close to the Boundary Waters Canoe Area Wilderness; significant mineral exploration is occurring within 1,000 yards of the wilderness’ borders.

One company, Franconia Minerals, intends to mine sulfide ores underneath Birch Lake, a significant recreational water body just outside Ely. The waters of the Kawishiwi River flow out of the BWCAW into Birch Lake and then, through the White Iron chain of lakes, back into the Boundary Waters.

Mineral exploration on public lands is extensive. In 2009, 32 permits were applied for to explore near the South Kawishiwi River (and the Little Gabbro Lake BWCAW entry point). In 2008, 74 such permits were approved. Extensive exploration is occurring on nearby state and private lands, as well.

Exploration activities can have serious impacts including water pollution, road-building, and even “miniature mines” where companies do “bulk sampling.” As the deposits are explored, the potential for the entire area to become a vast new mining district for these dangerous mines is real and worrisome to all who value the clean waters of the region.