Air Plan Partial Disapproval; Commonwealth of Pennsylvania; Reasonably Available Control Technology Regulations for the 1997 and 2008 Ozone National Ambient Air Quality Standards
As a result of the Third Circuit Court of Appeals' decision, dated August 27, 2020, in Sierra Club v. U.S. EPA, No. 19-2562 (3rd Cir. 2020), the Environmental Protection Agency (EPA) is proposing to partially disapprove a specific part of a state implementation plan (SIP) revision that had been previously approved by EPA. On May 19, 2019, EPA fully approved certain parts of a SIP revision submitted by the Commonwealth of Pennsylvania to address reasonably available control technology (RACT) for the 1997 and 2008 ozone national ambient air quality standards (NAAQS), and conditionally approved other parts of that submission. The court vacated EPA's approval of a portion of the SIP revision, as discussed below, and ordered that EPA either approve a new SIP revision addressing the court's decision or promulgate a federal implementation plan (FIP) within two years. EPA is therefore proposing to disapprove the portion of the SIP submission addressed by the court's decision. This action is being taken under the Clean Air Act (CAA).