US Senate Votes to End BWCA Mining Moratorium

The U.S. Senate voted 50-49 on April 17, 2026, to repeal a 20-year mining ban near Minnesota’s Boundary Waters Canoe Area Wilderness, clearing the way for a proposed copper and nickel mine by Twin Metals Minnesota, a subsidiary of Chilean mining conglomerate Antofagasta.

The resolution, which had already passed the U.S. House, now heads to President Donald Trump, who is expected to sign it, having previously advocated for ending the moratorium.

Business Implications for Antofagasta and Twin Metals

The vote represents a significant development for Antofagasta PLC, whose subsidiary Twin Metals Minnesota seeks to extract copper, nickel, cobalt, and other precious metals from underground veins near Ely and Babbitt, approximately a dozen miles from the Boundary Waters wilderness area.

Environmental and Legal Context

Environmental groups, including Save the Boundary Waters, have warned that sulfide mining in the region could contaminate the pristine waters of the Boundary Waters, which attracted nearly 150,000 visitors in 2024. Ingrid Lyons, executive director of Save the Boundary Waters, called the Senate vote “a dark day for America’s most beloved Wilderness area.”

Political Vote Details

The Senate vote fell along party lines with 50 Republicans in favor and 49 Democrats opposed. U.S. Senator Tina Smith of Minnesota spoke forcefully against the resolution, stating she was “keeping everyone up” late Wednesday because she believed constituents were wondering whether anyone in Congress cared about their views on protecting the Boundary Waters.

Next Steps

With the Senate approval complete, the resolution awaits President Trump’s signature. Once signed, it will formally end the Biden-era moratorium and allow Twin Metals Minnesota to advance its plans to develop the mining project in the Superior National Forest, though the company may still face legal challenges from conservation groups seeking to block the mine.