An 1,800-page scientific review to be released six days before Thanksgiving should provide the most in-depth insights to date to help answer a long-simmering question critical to Minnesota's future: Can copper, nickel and other precious metals be mined responsibly in the state's treasured northeast corner?

Given the daunting length and technical nature of the analysis of the proposed PolyMet mine near Babbitt — and more important, the critical need to balance the project's economic benefits and environmental risks — state and federal officials need to ensure that the public is given ample time to digest this information and weigh in.

While the informational review is not the final say on whether the project goes forward — that will follow in the permitting process — the public's chance to scrutinize one of the most comprehensive looks so far at the mine's impact on environmentally sensitive Arrowhead region's water, air and land should not be rushed. PolyMet and other proposed mines could bring good-paying jobs to the struggling region, but this type of mining also has an appalling environmental legacy — a history in Western states of leaving polluted waterways and other contamination to be cleaned up by taxpayers.

A project this important but controversial should not be dogged by questions about the public participation, which is why officials overseeing the review should work to avoid even the slightest perception that the comment period was inadequate.

How long the public will have to scrutinize the legally required analysis is unclear. While state officials announced recently that the review — known as an environmental-impact statement, or EIS — will be released publicly Nov. 22, they have not provided key details about the public comment process.

Not only is the length of the comment period unknown, there's also uncertainty about the number of meetings that will be held, their locations, and their formats.

Asked this week for these details, a Department of Natural Resources official said that his agency and the other two other "colead" agencies working on the PolyMet project are talking to each about this. A decision is likely to be released in November.

Steve Colvin, the DNR's deputy director of the division of ecological and water resources, did say that the public comment period will "certainly be longer" than the regulatory minimum of 45 days. But Colvin also directed an editorial writer to a federal database listing public comment period time frames for projects around the country, and noted that the longest that he'd seen was 105 days.

Colvin also said the DNR is working to make the technical information accessible and understandable. The information's Internet presentation will also help the public navigate the documents more easily.

Colvin's remarks are encouraging, though the agency's decision on the public comment period should be guided by its best judgment, not the 105-day ceiling it found for other projects. It's especially good to know that the agency is not thinking that the 45-day minimum would suffice — something that mining proponents such as Hoyt Lakes Mayor Mark Skelton advocated for this week.

PolyMet representatives also said this week that it's time to move forward on the project, adding that 90 days seemed "ample" and that 60-day public comment periods have worked for complex projects elsewhere. They also noted that environmental advocates have had a chance to see some information that will be in the EIS, and said that public comment opportunities are also provided during permitting.

While that's true, the Nov. 22 release will be the first time that the whole review will be available for the public and for environmental advocates, who plan to hire outside scientific experts to weigh the analysis. Minnesotans have an interest in having this type of second opinion done and done well. A long public comment period will inform citizens about permitting.

This is not the first EIS for the PolyMet project. Its first, released in late 2009, was sharply criticized by the U.S. Environmental Protection Agency, resulting in nearly another four years of work on the review to be released this fall. The public comment for the 2009 review was 90 days, with two meetings.

The EIS coming out Nov. 22 will no doubt be an improved analysis. The DNR and its colead agencies — the U.S. Army Corps of Engineers and the U.S. Forest Service — should aim to improve the public review process as well, and extend the time and opportunities for the public to learn about this important project.

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