On July 17th a three judge panel on the U.S. Court of Appeals for the Ninth Circuit in WildEarth Guardians v. EPA ruled that environmental groups did not have standing to challenge EPA’s approval of Nevada’s regional haze state implementation plan (SIP) for the Jarbridge Wilderness Area. The court also upheld EPA’s approval of Nevada’s SIP, which imposed SO2 limits for the Reid Gardner Generating Station. Rejecting environmentalists’ challenge to the SIPs as too weak, this ruling has bolstered EPA’s discretion to approve and disapprove regional haze SIPs. Following the decisions of the 8th and 10th Circuits regarding the Oklahoma and Nevada regional haze SIPs, the 9th Circuit is the third circuit court to defer to the EPA on the issue of regional haze requirements.