SUPPLEMENTARY INFORMATION:

I. Background

On February 6, 2026 (91 FR 5398), the EPA published a notice of proposed rulemaking (NPRM) for the Commonwealth of Pennsylvania. In the NPRM, the EPA proposed approval of a revision to the Pennsylvania SIP to amend source-specific RACT requirements for the 1997 8-hour ozone National Ambient Air Quality Standards (NAAQS) for a source in Philadelphia. As discussed in more detail in section II of this preamble, the revision updates the RACT requirements for the Philadelphia Gas Works, Richmond Plant (PGW Richmond) by removing a condition from the RACT Plan Approval that was previously incorporated into Pennsylvania's SIP. The proposed revision results in no change of emission allowances under RACT. The formal SIP revision was submitted by the Pennsylvania Department of Environmental Protection (PADEP), on behalf of the City of Philadelphia, Department of Public Health, Air Management Services (AMS), on September 7, 2023.

For additional background information on this action, please refer to the NPRM.

II. Summary of SIP Revision and the EPA Analysis

On October 7, 2016 (81 FR 69687), the EPA took final action to approve SIP revisions that were submitted by PADEP on behalf of AMS in order to satisfy RACT requirements of the 1997 ozone NAAQS applicable to sources located in Philadelphia. Included in that approval were source-specific requirements applicable to three 295 horsepower Caterpillar engines located at PGW Richmond. Specifically, Condition 1(B)(2) of AMS' July 9, 2015 RACT Plan Approval required that the timing of the engines be set and maintained at four degrees retarded relative to the standard timing.

On September 7, 2023, PADEP submitted to the EPA for approval, a SIP package that contains a revision to Pennsylvania's SIP to amend the source-specific RACT requirements for PGW Richmond by removing condition 1(B)(2). In this submittal, PADEP indicated that Condition 1(B)(2) was mistakenly included in the RACT Plan Approval for PGW Richmond. 25 Pennsylvania Code (Pa. Code) 129.93(c) contains a list of source types that are required to meet RACT through the “. . . installation, maintenance and operation of the source in accordance with manufacturers specifications.” Condition 1(B)(2) appears to have been included in order to constrain the engines in such a way that they would be subject to the presumptive RACT requirements of 25 Pa. Code 129.93(c). However, the engines as installed did not have timing as described in 25 Pa. Code 129.93(c)(3). Modifying the timing to four degrees retarded relative to standard timing would damage the engines and would be contrary to the presumptive RACT requirement the condition was intended to meet ( i.e. installation in accordance with manufacturers specifications). Furthermore, based on the permitted use of the three Caterpillar Engines 135GU 295 horsepower Units at PGW Richmond, AMS determined that the three emission units meet the criteria of 25 Pa. Code 129.93(c)(5), and are therefore still subject to the presumptive RACT requirement to install, maintain and operate the engines in accordance with manufacturer's specifications.

Removing Condition 1(B)(2) from the PGW Richmond RACT Plan Approval results in no change of emission allowances under RACT because the RACT requirement of 25 Pa. Code section 129.93(c) is the same for source categories listed in 25 Pa. Code section129.93(c)(3) and (c)(5). Updating this source type will remove the source as a case-by-case RACT requirement from the Pennsylvania SIP.

III. EPA's Response to Comments Received

The EPA received one comment in response to the NPRM. The comment was outside the scope of the rulemaking. As such, the comment does not require a response by the EPA.

IV. Final Action

The EPA is approving the revision to Philadelphia Gas Works, Richmond Plant Reasonably Available Control Technology Plan Under the 1997 8-Hour Ozone National Ambient Air Quality Standards as a revision to the Pennsylvania SIP.

V. Incorporation by Reference

In this document, the EPA is finalizing regulatory text that includes incorporation by reference. In accordance with requirements of 1 CFR 51.5, the EPA is finalizing the incorporation by reference of the revised RACT Plan Approval for PGW Richmond, as described in section II in this preamble. The EPA has made, and will continue to make, these materials generally available through www.regulations.gov and at the EPA Region III Office (please contact the person identified in the FOR FURTHER INFORMATION CONTACT section of this preamble for more information). Therefore, these materials have been approved by the EPA for inclusion in the SIP, have been incorporated by reference by the EPA into that plan, are fully federally enforceable under sections 110 and 113 of the CAA as of the effective date of the final rulemaking of the EPA's approval, and will be incorporated by reference in the next update to the SIP compilation.^[1]

VI. Statutory and Executive Order Reviews

Under the Clean Air Act, the Administrator is required to approve a SIP submission that complies with the provisions of the Clean Air Act and applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP submissions, the EPA's role is to approve state choices, ( printed page 31922) provided that they meet the criteria of the Clean Air Act. Accordingly, this action merely approves State law as meeting Federal requirements and does not impose additional requirements beyond those imposed by State law. For that reason, this action:

• Is not a significant regulatory action subject to review by the Office of Management and Budget underExecutive Order 12866 (58 FR 51735, October 4, 1993);
• Is not anExecutive Order 14192 (90 FR 9065, February 6, 2025) regulatory action because this action is not significant under Executive Order 12866;
• Does not impose an information collection burden under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
• Is certified as not having a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.);
• Does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4);
• Does not have federalism implications as specified inExecutive Order 13132 (64 FR 43255, August 10, 1999);
• Is not subject toExecutive Order 13045 (62 FR 19885, April 23, 1997) because it approves a state program;
• Is not a significant regulatory action subject toExecutive Order 13211 (66 FR 28355, May 22, 2001); and
• Is not subject to requirements of section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) because application of those requirements would be inconsistent with the Clean Air Act.

In addition, the SIP is not approved to apply on any Indian reservation land or in any other area where the EPA or an Indian Tribe has demonstrated that a Tribe has jurisdiction. In those areas of Indian country, the rule does not have Tribal implications and will not impose substantial direct costs on Tribal governments or preempt Tribal law as specified by Executive Order 13175 (65 FR 67249, November 9, 2000).

This rule is exempt from the Congressional Review Act because it is a rule of particular applicability.

Under section 307(b)(1) of the Clean Air Act, petitions for judicial review of this action must be filed in the United States Court of Appeals for the appropriate circuit by July 28, 2026. Filing a petition for reconsideration by the Administrator of this final rule does not affect the finality of this action for the purposes of judicial review nor does it extend the time within which a petition for judicial review may be filed, and shall not postpone the effectiveness of such rule or action. This action may not be challenged later in proceedings to enforce its requirements. (See section 307(b)(2).)

For the reasons stated in the preamble, the EPA amends 40 CFR part 52 as follows:

91 FR 31920