The Fond du Lac Band of Lake Superior Chippewa filed an appeal with the Minnesota Court of Appeals last week, asking the court to reject the Minntac national pollution discharge and disposal system permit as drafted and to require the Minnesota Pollution Control Agency to enforce all state water standards.

Band representatives called the MPCA permit “nearly toothless” in the filing.

In a statement issued Tuesday, the band noted that Minntac’s unlined, 12-square-mile tailings basin in Mountain Iron has long been acknowledged by owner U.S. Steel, the MPCA and tribal entities as “a sou...