Approval and Promulgation of Air Quality Implementation Plans and Designation of Areas for Air Quality Planning Purposes; Pennsylvania; Redesignation of Pittsburgh-Beaver Valley Ozone Nonattainment Area to Attainment and Approval of Miscellaneous Revisions

EPA is determining that the Pittsburgh-Beaver Valley moderate ozone nonattainment area (the Pittsburgh area) has attained the 1-hour ozone National Ambient Air Quality Standard (NAAQS) by its extended attainment date. The Pittsburgh area is comprised of Allegheny, Armstrong, Beaver, Butler, Fayette, Washington, and Westmoreland counties. This determination is based on three years of complete, quality-assured, ambient air quality monitoring data for the 1998 to 2000 ozone seasons that demonstrate that the ozone NAAQS has been attained in the area, and the most recent data which shows that the area is continuing to attain. On the basis of this determination, EPA is also determining that certain attainment demonstration requirements along with certain other related requirements of Part D of Title 1 of the Clean Air Act (the Act), are not applicable to the Pittsburgh area. EPA is also approving the Commonwealth of Pennsylvania's Department of Environmental Protection (PADEP) request to redesignate the Pittsburgh area to attainment of the 1-hour ozone NAAQS. The Commonwealth's formal request was dated May 21, 2001. In approving this redesignation request, EPA is also approving as a revision to the Pennsylvania State Implementation Plan (SIP), the Commonwealth's plan for maintaining the 1-hour ozone standard for the next 10 years. EPA is also approving the 1990 base year emission inventory for nitrous oxides (NO<INF>X</INF>). EPA is converting the limited approval of Pennsylvania's New Source Review (NSR) program to full approval throughout the Commonwealth with the exception of the 5-county Pennsylvania portion of the Philadelphia- Wilmington-Trenton ozone nonattainment area where it will retain its limited approval status until that area has an approved attainment demonstration for the 1-hour ozone standard.