If all the coal resources beneath the federally managed public lands in the U.S. were used, the nation wouldn't run out for at least six centuries, a report from the U.S. Geological Survey estimates. 

The Department of Interior released the report on Thursday, which estimates that there are 4.2 billion short tons of coal reserves associated with active mines and another 356 billion short tons of available coal resources. 

"American Energy Dominance is more important than ever, and so is beautiful clean coal’s role in the production of electricity needed to fuel our future prosperity,” Secretary of the Interior Doug Burgum, said in a statement. 

Wyoming's annual coal production remains the highest in the country. Of 34 miles on federal land, 14 are in Wyoming, and the Cowboy State holds 87% of the reported coal reserves associated with active mines on federal land.