The Environmental Integrity Project and Earthjustice issued a notice of intent July 18 to sue the Environmental Protection Agency for its failure to review the toxic air pollution emissions standards for petroleum refineries as required by the Clean Air Act. The environmental groups charge that the agency has missed the statutory deadline to review and revise national emissions standards for hazardous air pollutants for petroleum refineries and their catalytic cracking units, catalytic reforming units, and sulfur recovery units as required every eight years by the Clean Air Act. The groups released a second notice claiming that the agency is overdue to review the emissions factors it uses to estimate emissions of carbon monoxide, volatile organic compounds, and nitrogen oxides from flares, storage tanks, and wastewater treatment systems as required every three years under the Clean Air Act.