SUPPLEMENTARY INFORMATION:

Throughout this document “we,” “us,” and “our” refer to the EPA.

Table of Contents

I. Written Comments

II. What is being addressed in this document?

III. Have the requirements for approval of a SIP revision been met?

IV. What action is the EPA taking?

V. Incorporation by Reference

VI. Statutory and Executive Order Reviews

I. Written Comments

Submit your comments, identified by Docket ID No. EPA-R07-OAR-2026-5182, at https://www.regulations.gov. Once submitted, comments cannot be edited or removed from Regulations.gov. The EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. The EPA will generally not consider comments or comment contents located outside of the primary submission ( i.e., on the web, cloud, or other file sharing system). For additional submission methods, the full EPA public comment policy, information about CBI or multimedia submissions, and general guidance on making effective comments, please visit https://www.epa.gov/​dockets/​commenting-epa-dockets.

II. What is being addressed in this document?

The EPA is proposing to approve revisions to the Missouri SIP received on February 10, 2026. The revisions are to Title 10, Division 10 of the Missouri Code of State Regulations (CSR), 10 CSR 10-6.061 “Construction Permit Exemptions”. The purpose of the state regulation is to list specific construction or modification projects that are exempt from the requirement to obtain permits to construct under 10 CSR 10-6.060. Missouri made several revisions to the rule. These proposed revisions to the rule refine exemptions for emergency generators, update references within the rule and to other rules, and update recordkeeping requirements. The EPA proposes to find that these revisions meet the requirements of the CAA, do not interfere with any applicable requirement concerning attainment and reasonable further progress, and do not adversely impact air quality. The full text of the rule revisions as well as the EPA's analysis of the revisions are contained in the technical support document (TSD) included in the docket for this action.

III. Have the requirements for approval of a SIP revision been met?

The State submission has met the public notice requirements for SIP submissions in accordance with 40 CFR 51.102. The submission also satisfied the completeness criteria of 40 CFR part 51, appendix V. The State provided public notice on this SIP revision from June 16, 2025, to August 7, 2025, and held a public hearing on July 31, 2025. Missouri received no comments.

In addition, as explained above and in more detail in the TSD which is part of this docket, the revision meets the substantive SIP requirements of the CAA, including section 110 and implementing regulations.

IV. What action is the EPA taking?

The EPA is proposing to amend the Missouri SIP by approving the State's request to revise 10 CSR 10-6.061 “Construction Permit Exemptions.” We are processing this as a proposed action because we are soliciting comments on this proposed action. Final rulemaking will occur after consideration of any comments.

V. Incorporation by Reference

In this document, the EPA is proposing to include regulatory text in an EPA final rule that includes incorporation by reference. In accordance with requirements of 1 CFR 51.5, the EPA is proposing to finalize the incorporation by reference of the Missouri rule 10 CSR 10-6.061 as described in section II. of this preamble and as set forth below in the proposed amendments to 40 CFR part 52. The EPA has made, and will continue to make, these materials generally available through https://www.regulations.gov and at the EPA Region 7 Office (please contact the person identified in the FOR FURTHER INFORMATION CONTACT section of this preamble for more information).

VI. Statutory and Executive Order Reviews

Under the CAA, the Administrator is required to approve a SIP submission that complies with the provisions of the CAA 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 CAA. Accordingly, this action merely approves state law as meeting Federal requirements and does not ( printed page 48033) 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 CAA.

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).

For the reasons stated in the preamble, the EPA proposes to amend 40 CFR part 52 as set forth below:

1. The authority citation for part 52 continues to read as follows:

Authority: 42 U.S.C. 7401 et seq.

2. In § 52.1320, the table in paragraph (c) is amended by revising the entry “10-6.061” to read as follows:

91 FR 48032