The Environmental Protection Agency asked the U.S. Court of Appeals for the District of Columbia Circuit October 5 for a rehearing of an August 21 decision to vacate the Cross-State Air Rule. If the full court preserves the rule, power plants in 28 states would have to reduce SO2 and NOx emissions to help downwind states meet air quality standards. A group of nine states and six cities that intervened in the case on behalf of the agency filed a separate petition for rehearing the same day, as did a group of environmental and public health intervenors.