Air Plan Approval; Arizona; Maricopa County; Reasonably Available Control Technology-Combustion Sources

Publication Date: 
Thursday, August 4, 2022 - 4:00am

The Environmental Protection Agency (EPA) is proposing to approve a revision to the Maricopa County Air Quality Department's (MCAQD or County) portion of the Arizona State Implementation Plan (SIP). This revision concerns emissions of oxides of nitrogen (NO<INF>X</INF>) and particulate matter (PM) from combustion equipment and internal combustion (IC) engines. We are proposing to approve local rules to regulate these emission sources under the Clean Air Act (CAA or the Act) and to determine that the County's control measures implement Reasonably Available Control Technology (RACT) for major sources of NO<INF>X</INF> under the 2008 8-hour ozone National Ambient Air Quality Standard (NAAQS). We are taking comments on this proposal and plan to follow with a final action. Elsewhere in thi's Federal Register, we are making an interim final determination to defer CAA sanctions associated with our previous disapproval action concerning the County's RACT demonstration for major sources of NO<INF>X</INF>.

Environmental Protection Agency