A D.C. circuit court has denied a request by environmental groups challenging the EPA’s revisions to a final rule setting revised air toxic standards for cement kilns. The EPA initially issued the rule in 2010, and revised the rule in February 2013 to ease the particulate matter standard. The 2013 final rule also granted more time to cement kiln facilities to bring their facilities into compliance with the new, relaxed rule. Environmental groups argued that the Clean Air Act prohibits the EPA from setting emission standards that are less stringent than existing limits. While the court denied the stay, it did agree to expedite briefing in the litigation challenging the new standard. Final briefs are due in August 2013.