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

The Environmental Protection Agency (EPA) is proposing to approve elements of State Implementation Plan (SIP) revisions from the State of Montana to demonstrate the State meets infrastructure requirements of the Clean Air Act (Act or CAA) for the National Ambient Air Quality Standards (NAAQS) promulgated for ozone on March 12, 2008, lead (Pb) on October 15, 2008, nitrogen dioxide (NO 2 ) on January 22, 2010, sulfur dioxide (SO 2 ) on June 2, 2010 and fine particulate matter (PM 2.5 ) on December 14, 2012. EPA is also proposing to approve 110(a)(2)(D)(ii) for the 1997 and 2006 PM 2.5  NAAQS. EPA is proposing to conditionally approve CAA section 110(a)(2)(C) and (J) with regard to PSD and element 3 of 110(a)(2)(D)(i)(II) for the 2008 ozone, 2008 Pb, 2010 NO 2 , 2010 SO 2 , and 2006 and 2012 PM 2.5  NAAQS. EPA is proposing to disapprove element 4 of CAA section 110(a)(2)(D)(i)(II) for the 2008 ozone, 2010 NO 2 , 2010 SO 2,  and 2006 and 2012 PM 2.5  NAAQS. EPA is proposing to approve SIP revisions the State submitted to update Montana's PSD program and provisions regarding state boards. Section 110(a) of the CAA requires that each state submit a SIP for the implementation, maintenance, and enforcement of each NAAQS promulgated by EPA.