SUPPLEMENTARY INFORMATION:

I. Background

Each State has a SIP containing the control measures and strategies used to attain and maintain the national ambient air quality standards (NAAQS). The SIP is extensive, containing such elements as air pollution control regulations, emission inventories, monitoring networks, attainment demonstrations, and enforcement mechanisms.

Each State must formally adopt the control measures and strategies in the SIP after the public has had an opportunity to comment on them and then submit the proposed SIP revisions to the EPA. Once these control measures and strategies are approved by EPA, and after notice and comment, they are incorporated into the federally approved SIP and are identified in part 52, “Approval and Promulgation of Implementation Plans,” of title 40 of the Code of Federal Regulations (40 CFR part 52). The full text of the State regulation approved by the EPA is not reproduced in its entirety in 40 CFR part 52 but is “incorporated by reference.” This means that the EPA has approved a given State regulation or specified changes to the given regulation with a specific effective date. The public is referred to the location of the full text version should they want to know which measures are contained in a given SIP. The information provided allows the EPA and the public to monitor the extent to which a State implements a SIP to attain and maintain the NAAQS and to take enforcement action for violations of the SIP.

The SIP is a living document which the State can revise as necessary to address the unique air pollution problems in the State. Therefore, the EPA from time to time must take action on proposed revisions containing new or revised State regulations. A submission from a State can revise one or more rules in their entirety, or portions of rules. The State indicates the changes in the submission (such as by using redline/strikethrough text) and the EPA then takes action on the requested changes. The EPA establishes a docket for its actions using a unique Docket Identification Number, which is listed in each action. These dockets and the complete submission are available for viewing on www.regulations.gov.

On May 22, 1997 (62 FR 27968), the EPA revised the procedures for incorporating by reference, into the Code of Federal Regulations, materials approved by the EPA into each SIP. These changes revised the format for the identification of the SIP in 40 CFR part 52, streamlined the mechanisms for announcing the EPA approval of revisions to a SIP, and streamlined the mechanisms for the EPA's updating of the IBR information contained for each SIP in 40 CFR part 52. The revised procedures also called for the EPA to maintain “SIP Compilations” that contain the federally approved regulations and source-specific permits submitted by each State agency.

The EPA generally updates these SIP Compilations every few years. Under the revised procedures, the EPA must periodically publish an informational document in the rules section of the Federal Register notifying the public that updates have been made to a SIP Compilation for a particular state. The EPA began applying the revised IBR procedures to the Idaho SIP on January 25, 2005 (70 FR 3479) and subsequently published updates to the IBR materials in the Idaho SIP on December 28, 2012 (77 FR 76417), April 1, 2015 (80 FR 17333), July 24, 2020 (85 FR 44741), November 18, 2024 (89 FR 90592), and June 27, 2025 (90 FR 27470).

II. EPA Action

In this action, the EPA is providing notification of an update to the materials incorporated by reference into the Idaho SIP as of January 6, 2026, and identified in 40 CFR 52.670(c) and (d). This update includes SIP materials submitted by Idaho and approved by the EPA since the last IBR update. See90 FR 27470 (June 27, 2025). This action also corrects a minor typographical error from a previous EPA approval for the P4 Production LLC, Soda Springs, Idaho facility in which we inadvertently cited the nonexistent permit condition “13.33” instead of the correct citation “13.23.” See90 FR 42821 (September 5, 2025).

III. Good Cause Exemption

The EPA has determined that this action falls under the “good cause” exemption in section 553(b)(3)(B) of the Administrative Procedure Act (APA) which, upon finding “good cause,” authorizes agencies to dispense with public participation and section 553(d)(3) which allows an agency to make an action effective immediately (thereby avoiding the 30-day delayed effective date otherwise provided for in the APA). This administrative action simply codifies provisions which are already in effect as a matter of law in Federal and approved state programs and makes a correction a table in the CFR. Under section 553 of the APA, an agency may find good cause where procedures are “impracticable, unnecessary, or contrary to the public interest.” Public comment for this administrative action is “unnecessary” and “contrary to the public interest” since the codification (and corrections) only reflect existing law. Immediate notice of this action in the Federal Register benefits the public by providing the public notification of the updated Idaho SIP Compilation and notification of corrections to the Idaho “Identification of Plan” portion of the CFR. Further, pursuant to section 553(d)(3), making this action ( printed page 31933) immediately effective benefits the public by immediately updating both the SIP Compilation and the CFR “Identification of plan” section (which includes table entry corrections).

IV. 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 regulations promulgated by Idaho previously approved by the EPA and federally effective before January 6, 2026, contained in 40 CFR 52.670(c) and (d) as described in section I of this preamble. The EPA has made, and will continue to make, these materials generally available through www.regulations.gov and at the EPA Region 10 Office (please contact the person identified in the FOR FURTHER INFORMATION CONTACT section of this preamble for more information).

V. 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, 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, this action 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 action is subject to the Congressional Review Act, and the EPA will submit a rule report to each House of the Congress and to the Comptroller General of the United States. This action is not a “major rule” as defined by 5 U.S.C. 804(2).

The EPA also believes that the provisions of section 307(b)(1) of the Clean Air Act pertaining to petitions for judicial review are not applicable to this action. This is because prior EPA rulemaking actions for each individual component of the Idaho SIP Compilation previously afforded interested parties the opportunity to file a petition for judicial review in the United States Court of Appeals for the appropriate circuit within 60 days of such rulemaking action. Thus, the EPA believes judicial review of this action under section 307(b)(1) is not available.

For the reasons set forth in the preamble, 40 CFR part 52 is amended as follows:

91 FR 31932