Promulgation of State Implementation Plan Revisions; Infrastructure Requirements for the 2008 Lead, 2008 Ozone, 2010 NO2

The Environmental Protection Agency (EPA) is approving elements of State Implementation Plan (SIP) revisions from the State of Montana to demonstrate the State meets infrastructure requirements of the Clean Air Act (CAA) for the National Ambient Air Quality Standards (NAAQS) promulgated for ozone on March 12, 2008, lead (Pb) on October 15, 2008, nitrogen dioxide (NO2) on January 22, 2010, sulfur dioxide (SO2) on June 2, 2010 and fine particulate matter (PM2.5) on December 14, 2012. The EPA is also approving 110(a)(2)(D)(ii) for the 1997 and 2006 PM2.5 NAAQS. The EPA is conditionally approving CAA section 110(a)(2)(C) and (J) with regard to Prevention of Significant Deterioration (PSD) and element 3 of 110(a)(2)(D)(i)(II) for the 2008 ozone, 2008 Pb, 2010 NO2, 2010 SO2, and 2006 and 2012 PM2.5 NAAQS. The EPA is disapproving element 4 of CAA section 110(a)(2)(D)(i)(II) for the 2008 ozone, 2010 NO2, 2010 SO2, and 2006 and 2012 PM2.5 NAAQS. Finally, the EPA is approving SIP revisions the State submitted to update Montana's PSD program and provisions regarding state boards.