Appeals court rejects Minnesota's renewal of U.S. Steel mine permit
The Minnesota Court of Appeals reversed a state decision by state regulators that had granted U.S. Steel a permit to continue operations at its Minntac taconite iron ore mine in Mountain Iron, MN.
The Associated Press reported that the appeals court found that the Minnesota Pollution Control Agency (MPCA), which issued the permit to U.S. Steel, failed in its interpretation of state water-quality rules and that MPCA's decision regarding Minntac’s tailings discharge was unsupported. The court sent the dispute back to MPCA for further proceedings.
U.S. Steel was first issued the permit in 1987 and renewed it last year.
The five-year permit set long-range goals for U.S. Steel to meet for reducing pollutants, like sulfates, that are leaking out of the site’s 8,000-acre tailings basin into nearby surface and ground water.
In a statement, the MPCA shared that it’s assessing next steps.
"The Minnesota Pollution Control Agency is dedicated to protecting Minnesota’s most valuable resource — its water," the statement read. "The MPCA will continue engaging with stakeholders to ensure the state’s groundwater and surface water are protected.”
Minntac's ore processing facility in the city of Mountain Iron includes a 35.2 km2 (13.6 sq mile) tailings basin that holds mine waste and wastewater that's recycled for further ore processing. As a result, sulfate levels build up in the basin and water from it seeps into local ground and surface waters, The Associated Press reported.
Minnesota law restricts discharges of sulfates into waters where wild rice grows to 10 milligrams per liter. But the state for years has allowed Minntac to exceed that standard. The Legislature in 2011 put enforcement of the existing standard on hold and ordered the MPCA to develop new standards. The agency commissioned extensive research and drafted a complex new set of sulfate limits, but an administrative law judge rejected them last year.
The appeals court ruling came in a consolidated set of appeals by U.S. Steel, the environmental group WaterLegacy, and the Fond du Lac Band of Lake Superior Chippewa. U.S. Steel challenged the MPCA's denial of its request for a variance from ground water quality standards, while WaterLegacy and the tribe argued that the state agency erred in its interpretation of the federal Clean Water Act and drafted permit conditions that didn't sufficiently protect surface waters.
The Minnesota Center for Environmental Advocacy said in a statement that the court's ruling showed that the evidence failed to support the MPCA's decision that specific limits to prevent downstream pollution weren't necessary, but it also handed mining companies a win by preventing the state from enforcing ground water standards.
The MPCA said in a statement that while it reviews the court's decision and assesses its next steps, the agency “will continue engaging with stakeholders to ensure the state’s groundwater and surface water are protected.”