ST. PAUL, Minn. (AP) — The Minnesota Court of Appeals sent an air-emissions permit for the PolyMet copper-nickel mine back to state regulators for further review Monday, giving another victory to environmental groups who oppose the project.

The appeals court found that the Minnesota Pollution Control Agency did not adequately evaluate whether the air permit requested by PolyMet was a “sham permit" — meaning one that didn't accurately reflect the size and scope of PolyMet's proposed mine. This is the fourth permit the Court of Appeals has rejected this year.

PolyMet officials say they are disappointed and are reviewing their legal options. A spokesman for the MPCA said the agency was still reviewing the opinion.

Enter your number to get our free mobile app