NewRange Copper Nickel LLC (formerly PolyMet Mining Corporation ) needed a National Pollutant Discharge Elimination / State Disposal System (NPDES/SDS) permit for their proposed NorthMet Project. Located at the northern end of Minnesota’s Iron Range, the NorthMet Project includes an open pit copper-nickel mine, a beneficiation plant, and a tailings basin. To receive an NPDES/SDS permit, they needed to demonstrate that they would comply with state and federal regulations for the discharge of industrial wastewater and management of stormwater, as well as operation of the tailings basin, stockpiles, and ponds.
Barr had worked with PolyMet throughout the environmental review process and had a thorough understanding of the project and the estimated environmental effects. Before environmental review was complete, PolyMet engaged Barr to begin planning for permitting.
Barr worked with PolyMet to develop a permitting strategy and then implement it. Results of multiple models , including GoldSim and Modflow, were used to document that the project could meet state and tribal water quality standards. Many meetings with Minnesota Pollution Control Agency staff were vital to developing a shared understanding of the anticipated effectiveness of the project’s environmental controls.
One unique consideration was that the plant site was to be constructed at a former taconite processing facility, where the groundwater was contaminated by seepage from the legacy tailings basin. This meant that the NPDES/SDS permit application needed to show that PolyMet would not only manage pollutants from their operations but would also improve the legacy pollution.
Another unique circumstance was that Minnesota’s antidegradation rules were changing while the permit application and draft permit were being developed. It was unclear which set of rules would be in place when the permit was issued, so Barr developed a permit application that demonstrated compliance with both the old and the new antidegradation rules. The permit application was deemed complete, and in December of 2018, PolyMet was issued an NPDES/SDS permit for the NorthMet Project.