Air Plan Approval; Missouri; Control of Sulfur Emissions From Stationary Boilers

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Air Plan Approval; Missouri; Revisions to Existing Rule 10 CSR 10-5.570; Control of Sulfur Emissions From Stationary Boilers

A Rule by the Environmental Protection Agency on 04/09/2026

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3. Document Details Published Content - Document Details Agency Environmental Protection Agency Agency/Docket Numbers EPA-R07-OAR-2026-1785 FRL-13279-02-R7 CFR 40 CFR 52 Document Citation 91 FR 17855 Document Number 2026-06832 Document Type Rule Pages 17855-17857 (3 pages) Publication Date 04/09/2026 Published Content - Document Details

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• Document Details Published Content - Document Details Agency Environmental Protection Agency Agency/Docket Numbers EPA-R07-OAR-2026-1785 FRL-13279-02-R7 CFR 40 CFR 52 Document Citation 91 FR 17855 Document Number 2026-06832 Document Type Rule Pages 17855-17857 (3 pages) Publication Date 04/09/2026 Published Content - Document Details
• Document Dates Published Content - Document Dates Comments Close 05/11/2026 Effective Date 2026-06-08 Dates Text This direct final rule will be effective June 8, 2026, without further notice, unless the EPA receives adverse comment by May 11, 2026. If EPA receives adverse comments, we will publish a timely withdrawal of the direct final rule in the Federal Register informing the public that the rule will not take effect. Published Content - Document Dates

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  • AGENCY:
  • ACTION:
  • SUMMARY:
  • DATES:
  • ADDRESSES:
  • FOR FURTHER INFORMATION CONTACT:
  • SUPPLEMENTARY INFORMATION:
  • Table of Contents
  • I. What is being addressed in this document?
  • II. Have the requirements for approval of a SIP revision been met?
  • III. What action is the EPA taking?
  • IV. Incorporation by Reference
  • V. Statutory and Executive Order Reviews
  • List of Subjects in 40 CFR part 52
  • PART 52—APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS
  • Subpart AA—Missouri
  • Footnotes Enhanced Content - Table of Contents

• Related Documents Enhanced Content - Related Documents FederalRegister.gov uses the agency dockets published with the document to display related documents.

| EPA-R07-OAR-2026-1785
(2 Documents) | | | |
| --- | | | |
| Date | | Action | Title |
| | 2026-04-09 | Direct final rule. | Air Plan Approval; Missouri; Revisions to Existing Rule 10 CSR 10-5.570; Control of Sulfur Emissions From Stationary Boilers |
| | 2026-04-09 | Proposed rule. | Air Plan Approval; Missouri; Revisions to Existing Rule 10 CSR 10-5.570; Control of Sulfur Emissions From Stationary Boilers |

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Environmental Protection Agency

1. 40 CFR Part 52
2. [EPA-R07-OAR-2026-1785; FRL-13279-02-R7]

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Direct final rule.

SUMMARY:

The Environmental Protection Agency (EPA) is taking direct final action to approve revisions to the Missouri State Implementation Plan (SIP) submitted by the Missouri Department of Natural Resources (MoDNR). This direct final action will amend the SIP to address administrative changes to the State rule in the Missouri Code of State Regulations (CSR). Revisions include removal of references to a revoked State regulation and other minor administrative changes. The EPA is approving these changes because they are consistent with the Clean Air Act (CAA) and applicable EPA regulations.

DATES:

This direct final rule will be effective June 8, 2026, without further notice, unless the EPA receives adverse comment by May 11, 2026. If EPA receives adverse comments, we will publish a timely withdrawal of the direct final rule in the Federal Register informing the public that the rule will not take effect.

ADDRESSES:

Submit your comments, identified by Docket ID No. EPA-R07-OAR-2026-1785 to https://www.regulations.gov. Follow the online instructions for submitting comments. 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.

FOR FURTHER INFORMATION CONTACT:

Ashley Eichman, Environmental Protection Agency, Region 7 Office, Air and Radiation Division, 11201 Renner Boulevard, Lenexa, Kansas 66219; telephone number: (913) 551-7762; email address: eichman.ashley@epa.gov.

SUPPLEMENTARY INFORMATION:

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

Table of Contents

I. What is being addressed in this document?

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

III. What action is the EPA taking?

IV. Incorporation by Reference

V. Statutory and Executive Order Reviews

I. What is being addressed in this document?

The EPA is approving a revision to the Missouri SIP, submitted by the MoDNR on November 10, 2020. Specifically, the revisions are to a State rule at Title 10, Division 10 of the Code of State Regulations (CSR) 5.570, Control of Sulfur Emissions From Stationary Boilers, which is codified in the Missouri SIP at 40 CFR 52.1320(c). The purpose of the State regulation is to restrict emissions of sulfur dioxide from industrial boilers in the St. Louis, Missouri area. The administrative changes corrected abbreviations used for sulfur dioxide (SO 2), removed duplicative references to 40 CFR part 60, removed a citation to subpart A for appendix B of 40 CFR part 60, and ( printed page 17856) added punctuation. The full text of the rule revisions as well as EPA's analysis of the revisions can be found in the technical support document (TSD) included in this docket.

II. 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 July 15, 2019, to September 5, 2019, and received one comment from the EPA. The comment involved an issue surrounding 10 CSR 10-6.261 that at the time had not been approved into the SIP. 10 CSR 10-6.261 was approved into the SIP effective October 6, 2025. [1 ] As explained in the TSD included in the docket for this action, the revisions meet the substantive SIP requirements of the CAA, including section 110 and implementing regulations.

III. What action is the EPA taking?

We are publishing this direct final rule without a prior proposed rule because we view the amendment of the Missouri SIP to incorporate the revised State rule as routine and noncontroversial, and anticipate no adverse comments. The revisions to 10 CSR 10-5.570 will not affect the area's ability to attain or maintain any air quality standard because they are administrative in nature. However, in the “Proposed Rules” section of this Federal Register , we are publishing a separate document that will serve as the proposed rule to approve the SIP revision if adverse comments are received on this direct final rule. We will not institute a second comment period on this action. Any parties interested in commenting must do so at this time. For further information about commenting on this rule, see the ADDRESSES section of this document. If EPA receives adverse comment, we will publish a timely withdrawal in the Federal Register informing the public that this direct final rule will not take effect. We will address all public comments in any subsequent final rule based on the proposed rule.

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 incorporating by reference Missouri Regulations at 10 CSR 10-5.570, Control of Sulfur Dioxide Emissions From Stationary Boilers, as discussed in section I. of this preamble and set forth below in the 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).

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. [2 ]

V. 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 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 under Executive Orders 12866 (58 FR 51735, October 4, 1993);
• Is not subject to Executive Order 14192 (90 FR 9065, February 6, 2025) because SIP actions are exempt from review 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 in Executive Order 13132 (64 FR 43255, August 10, 1999);
• Is not subject to Executive Order 13045 (62 FR 19885, April 23, 1997) because it approves a state program;
• Is not a significant regulatory action subject to Executive 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 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 (CRA), and 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).

Under section 307(b)(1) of the CAA, petitions for judicial review of this action must be filed in the United States Court of Appeals for the appropriate circuit by June 8, 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)).

List of Subjects in 40 CFR part 52

• Environmental protection
• Air pollution control
• Carbon monoxide
• Incorporation by reference
• Intergovernmental relations
• Lead
• Nitrogen dioxide
• Ozone
• Particulate matter
• Reporting and recordkeeping requirements
• Sulfur oxides
• Volatile organic compounds Dated: March 31, 2026.

James Macy,

Regional Administrator, Region 7.

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

PART 52—APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

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

( printed page 17857) Authority: 42 U.S.C. 7401 et seq.

Subpart AA—Missouri

1. In § 52.1320, the table in paragraph (c) is amended by revising the entry “10-5.570” to read as follows:

§ 52.1320 Identification of plan. * * * * * (c) * * *

| Missouri citation | Title | State
effective date | EPA
approval date | Explanation |
| --- | --- | --- | --- | --- |
| Missouri Department of Natural Resources | | | | |
| | | | | |
|                                                       * | | | | |
| Chapter 5—Air Quality Standards and Air Pollution Control Regulations for the St. Louis Metropolitan Area | | | | |
| | | | | |
|                                                       * | | | | |
| 10-5.570 | Control of Sulfur Emissions From Stationary Boilers | 10/31/2019 | 4/9/2026, 91 FR [insert Federal Register page where the document begins] | |
| | | | | |
|                                                       * | | | | |

---

Footnotes

1.

                     See [90 FR 42839](https://www.federalregister.gov/citation/90-FR-42839) (September 5, 2025).

Back to Citation 2. 62 FR 27968 (May 22, 1997).

Back to Citation [FR Doc. 2026-06832 Filed 4-8-26; 8:45 am]

BILLING CODE 6560-50-P

Published Document: 2026-06832 (91 FR 17855)