Responsible Mining

Responsible mining is compatible with wilderness preservation, just as it has been throughout the more than 130-year history of mining in Minnesota. The state has long been a world leader in developing and upholding strict regulatory processes for the development of natural resources and modern mining.

Twin Metals Minnesota recognizes environmental stewardship as a core value and strives to be a leader in protecting Minnesota’s wilderness, natural environment, and recreational and cultural resources. Today’s environmental regulations tightly control how mines are designed and operated, and require bankruptcy-proof financial assurance for reclamation and closure performance. The Minnesota Department of Natural Resources, Minnesota Pollution Control Agency, U.S. Environmental Protection Agency, U.S. Army Corps of Engineers and other state and federal agencies will enforce regulations protecting water, soil, animals and air.

Twin Metals Minnesota is focused on developing and operating a safe mine – for workers and for the environment. We live, work and play here and care deeply about protecting the land, air and waters of Minnesota.

TMM recently submitted a formal mine plan proposal, initiating a rigorous and thorough environmental review by multiple state and federal agencies as required by law.

Some of the agencies with regulatory authority over the Twin Metals Minnesota project include:

  • Minnesota Department of Natural Resources
  • Minnesota Pollution Control Agency
  • Minnesota Department of Health
  • U.S. Environmental Protection Agency
  • U.S. Army Corps of Engineers
  • U.S. Forest Service
  • U.S. Bureau of Land Management

The TMM Project will minimize the surface footprint of mining activity by using underground mining operations coupled with storing half of tailings material as permanent cemented backfill in the underground mine. Twin Metals Minnesota will use the environmentally friendly dry stack method to manage the remaining tailings. Learn more about dry stack tailings storage. Testing shows the tailings would be non-acid generating. Extensive additional testing will be conducted under the supervision of the Minnesota Department of Natural Resources and federal agencies. The Project will not generate waste rock stockpiles.