The Boundary Waters Canoe Area Wilderness, America's most heavily visited wilderness area with over 150,000 annual visitors, faces an existential threat from a proposed copper and nickel mine. Conservation groups, tribal entities and local politicians have fought for more than a decade to permanently ban copper mining in the region, warning that sulfuric acid byproducts could contaminate the pristine Rainy River watershed.

Twin Metals Minnesota, a subsidiary of Chilean mining giant Antofagasta, holds two federal mineral leases on 4,800 acres of Forest Service land adjacent to the wilderness. Congress recently overturned a Biden administration mining ban in a narrow vote, with Representative Pete Stauber citing the need to develop critical minerals. The company must still prove it can meet Minnesota's stringent environmental standards through years of regulatory review.

The Minnesota Department of Natural Resources will ultimately grant or deny the mining permit. A state bill pending in the legislature would prohibit copper mining in the Boundary Waters headwaters, and voters could also pass a constitutional amendment to enshrine such a prohibition. The 1.1-million-acre wilderness sits within the 1854 Treaty Area, where the Ojibwe reserved hunting, fishing and gathering rights in perpetuity.