Environmental groups are hailing the U.S. Supreme Court’s rejection of an appeal challenging a federal rule that bars development on 50 million acres of roadless areas in national forests.

The justices said they will leave in place a federal appeals court decision in a case brought by the state of Wyoming and the Colorado Mining Association. It upheld the so-called roadless rule that took effect late in the presidency of Bill Clinton.

The decision ends one of the main legal battles that had left the rule in doubt for more than a decade.

Pew Environment Group director Jane Danowitz says the decision will protect millions of acres of pristine forest land.

Wyoming Governor Matt Mead said restrictions on 3 million acres of national forest in the state will have economic consequences for the state.