 A federal judge in Minnesota has lifted a hold that had been placed on four lawsuits challenging the proposed Polymet copper nickel mining northeastern Minnesota. Thursday's decision by U.S. District Judge Joan Erickson doesn't list next steps, but her decision to lift the stay means the cases can proceed. The lawsuits filed by environmental groups seek to block a land swap that Polymet needs to move forward. Polymet wants to swap 6,650 acres of federal land in the superior national forest for a similar amount of private land. Erickson put the cases on hold in March while Congress considered legislation that would have forced the land exchange, but that legislation didn't become law. The environmental groups say the deal undervalues the federal land and violates other laws. Polymet disputes that. If you enjoyed this segment of Lakeland News, please consider making a tax deductible contribution to Lakeland PBS.