Interstate Transport Prongs 1 and 2 for the 2010 Sulfur Dioxide (SO2

The Environmental Protection Agency (EPA) is approving portions of State Implementation Plan (SIP) submissions from Colorado, Montana, North Dakota, South Dakota and Wyoming addressing the Clean Air Act (CAA or Act) interstate transport SIP requirements for the 2010 sulfur dioxide (SO2) National Ambient Air Quality Standard (NAAQS). These submissions address the requirement that each SIP contain adequate provisions prohibiting air emissions that will have certain adverse air quality effects in other states. The EPA is approving portions of these infrastructure SIPs for the aforementioned states as containing adequate provisions to ensure that air emissions in the states will not significantly contribute to nonattainment or interfere with maintenance of the 2010 SO2 NAAQS in any other state.