Republican U.S. Rep. Pete Stauber has reintroduced legislation to overturn a 20-year mining ban near the Boundary Waters Canoe Area Wilderness that was imposed two years ago under the Biden administration.

The bill would also return two key federal mineral leases to Twin Metals Minnesota, the company vying to build an underground mine for copper and nickel near Ely, on the shore of Birch Lake, just south of the wilderness.

Twin Metals is owned by the Chilean mining conglomerate Antofagasta. The Biden administration revoked those leases in 2022.

Stauber, who represents Minnesota’s 8th District where the project would be built, originally introduced the bill in 2023. It passed the GOP-controlled U.S. House but was never taken up by the Democratically controlled Senate.

Now that Republicans control both chambers in Congress, the bill stands a much greater chance of passing.

President Donald Trump has also promised to undo the mining ban, which covers about 350 square miles of the Superior National Forest within the watershed of the Boundary Waters. That means any potential water pollution from mines there could flow into the wilderness area.

Biden’s Department of the Interior imposed the so-called “mineral withdrawal” after conducting an environmental review that found potential mining projects in the region posed too great a risk of doing “irreparable harm” to the watershed.

On the presidential campaign trail last year, at a stop in St. Cloud with Stauber at his side, Trump promised to undo the mining moratorium in “about 10 minutes.”

While Trump has yet to act specifically on the Twin Metals leases or the mineral withdrawal in the Superior National Forest, new Interior Secretary Doug Burgum signed an order this week calling for the reinstatement of natural resource leases canceled during Biden’s term, and for the review and revision of withdrawn public lands.

Environmental groups immediately pushed back against Stauber’s bill, arguing it would strip important protections from more than 225,000 acres of land, and open it up to a kind of mining that poses much more severe water pollution risks than iron ore mining, which has been conducted in the region for 140 years.

“It puts pollution over clean water. We will challenge this decision through every available avenue,” said Chris Knopf, executive director of Friends of the Boundary Waters.

Ingrid Lyons, executive director of Save the Boundary Waters, called Stauber’s bill a “giveaway” of the country’s most popular wilderness area.

The bill “undermines the robust record of science, public opinion, law and economics that clearly demonstrates that this iconic American landscape is absolutely no place for our nation’s most dangerous industry,” she added.

In addition, Stauber’s bill would also limit opponents’ ability to file lawsuits to block the return of leases to Twin Metals. A spokesperson for Stauber said “well-funded activist groups who oppose mining of any kind should not be able to weaponize the courts” to hold up the project.

Environmental groups have called that provision in the bill “radical,” for eliminating review by the judicial branch, the third branch of government.

Meanwhile, U.S. Rep. Betty McCollum, D-Minn., who represents the St. Paul area, introduced legislation two weeks ago to make the 20-year mining ban permanent.

“The Boundary Waters are a national treasure that must be protected,” McCollum said when she introduced the bill.