The United States Environmental Protection Agency (USEPA) is approving a year-round oxygenated fuels program as a revision to Minnesota's State Implementation Plan (SIP) for carbon monoxide (CO). The use of oxygenated fuels can reduce emissions of CO from vehicles, thereby reducing the threat to human health posed by CO, which can contribute to heart and lung disease and reduce the concentration of oxygen in the blood stream. Minnesota already has an approved SIP which requires the use of oxygenated fuels during the winter; the extension of the oxygenated fuels program beyond the winter months will serve as the contingency measure required for nonattainment plans under section 172(c)(9) of the Clean Air Act (the Act). USEPA's action is based upon a SIP revision request which was submitted by the State to satisfy the requirements of the Act.