Montana U.S. Sen. Jon Tester has asked the Obama administration to take steps to block a pair of mining proposals outside Yellowstone National Park.
Tester made the request in a Thursday letter to leaders of the U.S. Departments of Agriculture.
The Democratic lawmaker says the Yellowstone area and Absaroka-Beartooth Wilderness deserve special protections because of their beauty and ecological value.
The Montana Department of Environmental Quality released a draft environmental review of one of the projects on Thursday.
It said Lucky Minerals' proposal to explore for gold and other metals near Emigrant would not have a significant environmental impact.
A second company, Crevice Mining Group, is seeking to permission to explore for gold near Jardine, just north of the park.
Additional approvals would be needed for large-scale mining.