Sixty blacked-out pages. That's what keeping secret the science involving copper mining's risks to the Boundary Waters Canoe Area Wilderness (BWCA) watershed looks like.

In a congressional hearing last week, U.S. Rep. Betty McCollum held up the heavily redacted report from the U.S. Department of Agriculture as she demanded to know why the study's findings haven't been shared with Congress or the public. It's a good question, one that the Star Tribune Editorial Board has asked repeatedly over the past year, and there are still no satisfactory answers.

Thanks to legal action by the Wilderness Society, the redacted study is now publicly available, and those that want to see it can do so online at The cover sheet is readable. The rest of it is blocked out, illustrating that the administration shut down this two-year study four months before its completion, and it continues to keep Americans in the dark about what it found.

That's unacceptable and suggests strongly that the study's findings show that copper mining's potential pollution poses a serious risk to the BWCA. The wilderness lies downstream from one of the major copper mines proposed in the state — Twin Metals Minnesota, which seeks to operate near the wilderness and next to a reservoir whose waters flow into the BWCA. The other copper mining project, PolyMet, lies outside the wilderness watershed.

Congress has unsuccessfully sought the study results since late 2018. McCollum's demands last week to see the full findings were met with more stonewalling by administration officials.

Taxpayers paid for this study. They deserve better than 60 censored pages.