HEAL Utah, the National Parks Conservation Association, the Powder River Basin Resource Council, and the Sierra Club filed petitions for review in the U.S. Court of Appeals for the 10th Circuit in Denver January 25 challenging regional haze plans the Environmental Protection Agency approved for New Mexico, Utah, and Wyoming. The groups also filed a petition challenging the agency’s approval of a regional haze plan by Albuquerque, New Mexico. WildEarth Guardians filed its third legal challenge in two weeks January 23 involving a state implementation plan for regional haze, calling Utah’s plan ineffective.