DFL Rep. Betty McCollum wants the federal government to examine the pollution risk posed to Canada from the proposed Twin Metals copper-nickel mine in northeastern Minnesota, near the Boundary Waters.
McCollum's research request, tucked into a spending bill approved earlier this week by the House Appropriations Committee, came a day after the Trump administration renewed controversial 10-year mineral leases for the proposed underground mine.
Barring action from a federal judge, Twin Metals is now clear to submit a mine plan of operation for its proposed underground copper-nickel mine, a step that would trigger a multi-year state and federal environmental review and permitting process.
• Related: Retired Forest Service officials raise concerns about Twin Metals
• May 2018: Twin Metals releases updated plans for copper-nickel mine near Ely
The language McCollum inserted into the funding bill expresses concern that the newly renewed leases will result in a mine that risks polluting waters along the U.S.-Canadian border, including the Boundary Waters and Ontario's Quetico Provincial Park, in violation of a century-old treaty.
It directs the U.S. State Department to detail how the federal government plans to "monitor and mitigate" the risk of acid mine drainage flowing to Canadian waters and how the Canadian government will be briefed on the "potential for cross-boundary pollution."
McCollum opposes Twin Metals' plan. She wants to make the controversial mine an international issue, said Bill Harper, her chief of staff. The 1909 Boundary Waters Treaty, he said, "explicitly states that one side shall not pollute the waters of the other side."
The mine is expected to be built near Ely, Minn., about five miles from the southern edge of the Boundary Waters.
Twin Metals executives have said repeatedly it's premature to speculate on potential impacts until the company submits its official mine plan and regulators produce an environmental impact statement — a process that would take years and which would detail the mine's anticipated environmental effects and the company's plans to mitigate them.
Twin Metals officials say they plan to nail down final details of that plan over the next two months, and expect to submit it to state and federal regulators later this year.
U.S. GOP House Reps. Tom Emmer and Pete Stauber praised the Interior Department's lease renewal decision and were present for the signing ceremony. They argue Minnesota can both protect the environment and develop its rich mineral resources.
Stauber, who represents northeastern Minnesota, said in a statement that McCollum's amendment was "anti-mining" and "ignores the will of my constituents by halting mining in northern Minnesota and robbing our communities of job growth and economic prosperity."
Canadian officials have expressed concerns about a potential mine.
In a letter to the federal Bureau of Land Management in January, Eric Walsh with Global Affairs Canada, which manages Canada's diplomatic relations, wrote "Canada is concerned about the potential for increased mining activity within the basin which could contaminate boundary waters if not properly assessed and managed, putting Canadian water quality and ecosystems at risk."