Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Philadelphia County Reasonably Available Control Technology Under the 1997 8-Hour Ozone National Ambient Air Quality Standards

The Environmental Protection Agency (EPA) is approving state implementation plan (SIP) revisions submitted by the Commonwealth of Pennsylvania (Pennsylvania). The revisions pertain to a demonstration that Philadelphia County (Philadelphia) meets the requirements for reasonably available control technology (RACT) of the Clean Air Act (CAA) for nitrogen oxides (NO<INF>X</INF>) and volatile organic compounds (VOC) as ozone precursors for the 1997 8-hour ozone national ambient air quality standards (NAAQS). In this rulemaking action, EPA is approving three separate SIP revisions addressing RACT under the 1997 8-hour ozone NAAQS for Philadelphia; approving portions of two previously submitted RACT SIP revisions, which EPA had found deficient and conditionally approved; and converting the prior conditional approval of the Philadelphia RACT demonstration for the 1997 8-hour ozone NAAQS to full approval. EPA is approving these revisions to the Pennsylvania SIP addressing 1997 8-hour ozone RACT for Philadelphia in accordance with the requirements of the CAA.