[environmental groups sue to cancel Minnesota's PolyMet opencast copper and gold mine deal] environmentalists sued the U.S. Forest Service on Tuesday in an attempt to overturn the 2017 land transfer to PolyMet Mining to build an open-pit copper and gold mine in northern Minnesota. The lawsuit, led by (CBD), a biodiversity center, claims that the project will destroy the homes of Canadian lynx and northern long-eared bats, both of which are listed as endangered under the US Endangered species Act.