On March 6, the Department of Natural Resources (DNR) closed the discretionary public comment period for the draft Permit to Mine for the proposed PolyMet mine. This followed similar comment periods last fall on other draft DNR permits for this project, which, if ultimately permitted, would be Minnesota's first copper-nickel mine.

The DNR now moves into a critical deliberative phase with this project. The agency and its consultants are reviewing approximately 22,000 public comments, objections and petitions for a contested case hearing.

For a large project such as PolyMet, the regulatory process is complex. We have gone to unprecedented lengths to do our work as thoroughly and transparently as possible, including posting applications and technical reports online in real time and providing for public comment — even when not required by law.

Despite these efforts, we understand there are inevitable questions and concerns. There have been several recent media stories ("PolyMet debate turns to waste dump," April 8) and interest group statements suggesting that the DNR ignored its staff and consultants in developing draft PolyMet permits. Most of these assertions center on the DNR's review of the proposed tailings basin, but others have involved climate change, financial assurance and other topics. Some have relied on isolated comments taken entirely out of context.

If there is one thing that PolyMet's passionate proponents and opponents should agree on, it's that the DNR (and the Minnesota Pollution Control Agency) must ultimately follow the process and the rigorous standards established in state law. Minnesota's environment, economy and communities deserve no less.

These statutory processes do not allow the DNR to pick and choose the information we use in decisionmaking. The DNR must engage in a rigorous, neutral and highly technical process. Done properly, this process involves robust internal debate during which the DNR often weighs diverse points of view.

Many of the recent assertions about how the DNR has considered staff and consultant recommendations take individual statements out of context, without acknowledging or considering other information in our record, subsequent steps the DNR took in response to these recommendations or the myriad factors the DNR must evaluate and balance.

For example, cautions from staff and consultants about the maintenance requirements of the proposed tailings basin design have been misrepresented as conclusions that the design, with proper maintenance, is inherently unsafe. All things being equal, would a tailings design that required no maintenance be preferable? Yes, absolutely. Are all factors equal across alternative designs? No.

In addition to maintenance, we must consider wetlands impacts, water chemistry, energy consumption, air emissions and myriad other factors. In our evaluation of the proposed tailings basin design, our state dam engineers have worked closely with external dam safety consultants, including an internationally recognized expert with experience evaluating dam failures.

With any project, DNR staff and consultants engage in dialogue on the effectiveness of a proposed plan throughout environmental review and consideration of permit applications. That process is iterative and often leads to additional analysis, design changes or permit conditions. Our current step involves considering the large volume of public comments received on our draft permits. We do that neutrally and rigorously, as we determine whether draft permit changes are needed or whether an administrative law judge should review some questions before we complete our decisionmaking.

Failure to do exactly what a staff person, consultant or member of the public suggests at a particular point in time does not equate to ignoring that perspective. Our record thus far proves this point. We are fully committed to completing our careful consideration of all comments on the draft Permit to Mine, dam safety and water appropriations permits.

As we do this, personal opinions about the proposed project are immaterial. What we must do — and will do — is fulfill our responsibilities under Minnesota's stringent laws, while protecting our environment, public safety and taxpayers.

We currently have more than 40 people participating in the review and consideration of public comments, and I want to emphasize that there have been no final decisions.

All of us at the DNR take our responsibility seriously, and we are committed to ensuring the most rigorous application of state standards to this project. This will be the most studied and — if permitted — the most closely regulated project in Minnesota's history. As it should be.

Tom Landwehr is commissioner of the Minnesota Department of Natural Resources.