EPA completes Minnesota St. Louis River sediment cleanup with $30.5M activated carbon project at Thomson Reservoir
scienceblog.comEPA and Minnesota partners marked completion of the final sediment remediation project on the Minnesota side of the St. Louis River, a cleanup that began in 2018 and wrapped up in 2026. The last project at Thomson Reservoir treated 225,000 cubic yards of contaminated sediment using activated carbon, a technique that binds dioxins and furans in place rather than dredging them out. The $30.5 million effort is one of the largest of its kind in North America. Earlier projects included capping at Minnesota Slip and excavation of old timber waste. Funding came from the Great Lakes Restoration Initiative and the Bipartisan Infrastructure Law, with over $250 million in federal investment leveraged by $208 million from state and local partners. The St. Louis River is not fully delisted yet, with habitat work and Wisconsin-side projects still pending, but the sediment cleanup milestone is a major step.