The proposed PolyMet mine project, located at the headwaters of the St. Louis River, the largest U.S. tributary to Lake Superior, would destroy or impair more than 1,000 acres of wetlands and leach toxic metals like mercury, lead and arsenic into our waters. PolyMet’s tailings waste dam uses the same cheap design as the tailings dam that catastrophically failed in Brazil in early 2019, killing over 250 people.