Federal authorities have proposed new regulations that would force the Minnesota and Michigan iron mining industry to slash its mercury emissions.
The rule announced by the U.S. Environmental Protection Agency last week follows two decades of litigation and other pressure by tribes and environmental groups who have long urged the agency to adopt mercury limits.
The six iron ore processing plants in northeastern Minnesota would be required to cut their emissions by 57% by the end of 2026. They're the largest source of mercury pollution in Minnesota, accounting for about half its emissions. The rule also applies to two mining operations in Michigan's Upper Peninsula. Virtually all U.S. iron ore processing occurs at those Michigan and Minnesota mines.
"We’re glad to see some limits at long last on this pollution," James Pew, an attorney with Earthjustice, told Minnesota Public Radio. He sued the EPA on behalf of the Fond du Lac Band of Lake Superior Chippewa and two environmental groups.
But Pew said the EPA should have gone further, especially considering that limits were supposed to be put in place decades ago. Congress in 1990 first required the EPA to set mercury emission standards for the plants by 2000, but the agency never did.
"Instead the agency has allowed it to build up for the last 20 years, and mercury is a persistent pollutant, so we’ve still got all the mercury that was emitted over the last 20 years in the environment," Pew said.
The Minnesota Pollution Control Agency said the plants must submit updated plans in Spring 2024.
Cleveland-Cliffs and U.S. Steel own and operate the eight iron mines and plants in Minnesota and Michigan. They told the Star Tribune of Minneapolis that they’re reviewing the draft limit. U.S. Steel has said previously that none of the available technologies could achieve the 72% cut and 30% was more realistic. The MPCA has disputed that and said technologies are available.