U.S District Judge Marcia Krieger set aside the plan Friday and ordered the agency to take another look. A BLM official didn't immediately return messages seeking comment Friday night.

Environmentalists sued in 2008 after the BLM approved drilling in phases on the Roan, including the largely undeveloped top of the plateau.

Krieger found the BLM violated procedure by failing to sufficiently address an alternative that would have left much of the surface of the plateau undisturbed. She says it also failed to sufficiently address cumulative effects of drilling on air quality over time and potential ozone impacts.

(Copyright 2012 by The Associated Press. All Rights Reserved.)