U.S. Rep. Betty McCollum's new bill to ban copper mining in the Boundary Waters Canoe Area Wilderness watershed had its first hearing Wednesday, and a Republican opponent made an excellent point.

The decision on whether to open a copper mine near the BWCA or elsewhere should be based on facts, said Rep. Paul Gosar, R-Arizona.

The Star Tribune Editorial Board, which supports McCollum's bill, couldn't agree more. The trouble is that a tranche of facts, ones gathered by scientists, has deliberately been kept secret during the debate over a mine that would be perilously close to the BWCA. The mine is proposed by Twin Metals Minnesota, which is owned by Chile's Antofagasta mining conglomerate.

A two-year study of copper mining's risks to this sensitive watershed had been commissioned under the Obama administration. It was halted in September 2018 by the Trump administration just months before its completion.

The Trump administration has defied multiple requests from members of Congress and the Editorial Board to access the information gathered. On Wednesday, it was clear that this information will continue to remain under wraps, according to an administration representative who testified. When asked why, his mumbling failed to provide a logical answer.

Among other key points made during the hearing, the former head of the U.S. Forest Service said that pollution cannot be remediated once it's in the BWCA. And the process begun under the Obama administration to withdraw the land from mining began long before the former president left office.

So, yes, let's have all the facts as federal and state officials evaluate allowing an industry with an atrocious track record of pollution to build a mine next to a river flowing into the BWCA. But until the Trump administration releases the results of the aborted study, the facts are far from complete.