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

The Environmental Protection Agency (EPA) is proposing to approve elements of State Implementation Plan (SIP) revisions from the State of Colorado to demonstrate the State meets infrastructure requirements of the Clean Air Act (Act, CAA) for the National Ambient Air Quality Standards (NAAQS) promulgated for ozone on March 12, 2008; lead (Pb) on October 15, 2008; and nitrogen dioxide (NO2) on January 22, 2010. 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.