ST. PAUL, Minn. (AP) — The Minnesota Department of Natural Resources has denied requests to reconsider the tailings dam permits that it issued for the planned PolyMet copper-nickel mine.

The DNR said Wednesday that opponents did not raise any new issues that materially affect its 2008 decision granting the permits.

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The Fond du Lac Band of Chippewa and environmental groups asked the DNR to reconsider in light of tailings dam failures elsewhere. DNR Commissioner Sarah Strommen said in a statement that her agency studied the failures but remains confident in the safety of the PolyMet dam.

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The DNR issued its decision one day after the Minnesota Court of Appeals stayed a different permit for the mine, governing water pollution, pending a court investigation into potential irregularities in how state and federal regulators handled that permit.

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