2025-15440: Air Plan Approval; Missouri; Removal of Obsolete Rules on Control of NOX Emissions

Federal Register, Volume 90 Issue 155 (Thursday, August 14, 2025) [Federal Register Volume 90, Number 155 (Thursday, August 14, 2025)] [Rules and Regulations] [Pages 39128-39130] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 2025-15440] ----------------------------------------------------------------------- ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 52 [EPA-R07-OAR-2025-0138; FRL-12693-02-R7] Air Plan Approval; Missouri; Removal of Obsolete Rules on Control of NOX Emissions

Agency

Environmental Protection Agency (EPA).

Action

Final rule. -----------------------------------------------------------------------

Summary

The Environmental Protection Agency (EPA) is taking final action to approve a revision to the State Implementation Plan (SIP) submitted by the Missouri Department of Natural Resources (MoDNR) on November 14, 2018. MoDNR requested that the EPA remove from its SIP two rules related to control of emissions of nitrogen oxides (NOX). One of the rules previously applied to electricity generating units (EGUs) and certain non-EGUs in a portion of the state and the other rule previously applied to EGUs throughout the entire state. The EPA has already approved a SIP revision that included provisions to sunset the two rules, and removal of the now-sunsetted rules from the SIP would not have an adverse effect on air quality. The EPA's approval of this rule revision is being done in accordance with the requirements of the Clean Air Act (CAA).

Dates

This final rule is effective on September 15, 2025.

Addresses

The EPA has established a docket for this action under Docket ID No. EPA-R07-OAR-2025-0138. All documents in the docket are listed on the https://www.regulations.gov website. Although listed in the index, some information is not publicly available, i.e., Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the internet and will be publicly available only in hard copy form. Publicly available docket materials are available through https://www.regulations.gov or please contact the person identified in the FOR FURTHER INFORMATION CONTACT section for additional information.

For Further Information Contact

William Stone, Environmental Protection Agency, Region 7 Office, Air Permitting and Planning Branch, 11201 Renner Boulevard, Lenexa, Kansas 66219; telephone number: (913) 551-7714; email address: [email protected].

Supplementary Information

Throughout this document ``we,'' ``us,'' and ``our'' refer to 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. The EPA's Response to Comments IV. What action is the EPA taking? V. Incorporation by Reference VI. Statutory and Executive Order Reviews

I. What is being addressed in this document?

The EPA is approving the removal of 10 Code of State Regulations (CSR) 10-6.360, Control of NOX Emissions From Electric Generating Units and Non-Electric Generating Boilers (referred to here as the Missouri NBTP Rule), and 10 CSR 10-6.350, Emission Limitations and Emissions Trading of Oxides of Nitrogen (referred to here as the Missouri EGU Emission Rate Rule), from the Missouri SIP.

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 February 28, 2018, to April 5, 2018 and received one comment from the EPA. Missouri's official submission addressed the EPA's comment. In addition, as explained above the revision meets the substantive SIP requirements of the CAA, including section 110 and implementing regulations.

III. The EPA's Response to Comments

The public comment period on the EPA's proposed rule opened April 28, 2025, the date of its publication in the Federal Register and closed on May 29, 2025. During this period, EPA received comments from four commenters. Comment 1: One comment did not identify a specific issue that was relevant to the proposed rule and [[Page 39129]] therefore does not require a response. The comment can be found in the docket for this action. Comment 2: Two commenters were concerned that the removal of these rules could lead to an increase in ``greenhouse gases (GHG) like Nox'' emissions. Response: As stated in the proposal, the rules were sunsetted in 2009 and have not been in effect since that time. This action has no effect on ozone-precursor emissions and thus, no direct or indirect effects with respect to GHGs or climate change. Comment 3: The commenter stated that EPA should require an analysis of the air quality or public health impacts from removing these NOX control rules, especially vulnerable and low-income groups. Response: Please see response to Comment 2. Because the rules were sunsetted in 2009 and no substantive provisions of the Missouri NBTP Rule and the Missouri EGU Emission Rate Rule remain operative, this action has no effect on emissions or air quality. Comment 4: The commenter stated that EPA should require Missouri to correct a compliance gap for large non-EGUs in eastern Missouri with a deadline. Response: This action only removes obsolete provisions from the Missouri SIP. As noted in the NPRM, while the EPA has identified the existence of this compliance gap for NOX SIP Call-affected large non-EGUs in eastern Missouri, the removal of the already- sunsetted rules from the state's SIP would not have any effect on the compliance gap. See 90 FR at 17754. As EPA further states in the NPRM, the EPA remains ready to assist Missouri in remedying the gap, but that remedy is beyond the scope of this action. Comment 5: The commenter stated that EPA and Missouri should perform environmental justice reviews to prevent disproportionate impacts on marginalized, low-income, or Black communities for SIP revisions. Response: Please see response to Comment 3. Because no substantive provisions of the Missouri NBTP Rule and the Missouri EGU Emission Rate Rule remain operative, the rules currently have no effect on emissions or air quality. Comment 6: The commenter stated that NOX emissions, seasonal trends and ozone readings should be publicly posted. Response: The state of Missouri \1\ and the EPA publicly post ozone levels from each monitor \2\ and annual NOX emissions are publicly available from the EPA's National Emissions Inventory (NEI).\3\ More detailed emissions data is available for sources regulated by the EPA's Clean Air Markets Program Data (CAMPD).\4\ --------------------------------------------------------------------------- \1\ Air Quality Analysis Ozone--Weekly Monitor Data [verbar] Missouri Department of Natural Resources. \2\ Air Quality Design Values [verbar] US EPA. \3\ Get Air Emissions Data [verbar] US EPA. \4\ Clean Air Markets Program Data (CAMPD) [verbar] US EPA. --------------------------------------------------------------------------- Comment 7: The commenter stated that the rule should be reinstated if air quality deteriorates or the ozone non-attainment areas expand. Response: As stated in the proposal, this rulemaking only removes obsolete provisions of the Missouri SIP. Further, these rules are no longer in effect and have not been since 2009. There are ongoing ozone season requirements for EGU sources. Missouri's large EGUs continue to participate in the interstate Cross-State Air Pollution Rule (CSAPR) Ozone Season Group 2 Trading Program (the CSAPR OS G2 trading program), as required by the Missouri CSAPR OS G2 Rule. See 90 FR at 17753. In addition, for the state's NOX SIP Call-affected large non- EGUs, the Missouri Clean Air Interstate Rule (CAIR) OS Rule's requirements to monitor seasonal NOX emissions in accordance with 40 CFR part 75 remain federally enforceable SIP requirements, notwithstanding the fact that the EPA has stopped carrying out its functions administering the trading program elements of that rule and the fact that the state has removed the rule from the state's regulations. Those monitoring requirements remain codified federal law. See id. 17753-54. Comment 8: The commenter stated that EPA should track GHG emission co-benefits from EGU controls for NOX. Response: As stated in the proposal, this rulemaking only removes obsolete provisions of the Missouri SIP. GHG tracking is beyond the scope of the rulemaking. Comment 9: The commenter stated that Missouri should do meaningful community engagement for SIP revisions and provide information in multiple languages. Response: The State submission has met the public notice requirements for SIP submissions in accordance with 40 CFR 51.102. Comment 10: The commenter stated that EPA should clarify how this action will be impacted by pending litigation on interstate transport. Response: Since the rules being removed are no longer in effect and have not been since 2009, this action is not affected by or relevant to more recent interstate transport litigation, which generally concerns interstate transport obligations for the 2015 ozone NAAQS. Comment 11: The commenter stated that EPA should require Missouri to assess and mitigate any negative impacts on workers in the EGU and non-EGU sectors, including air quality monitoring professionals during regulatory transitions. Response: As stated above, this rulemaking is limited to the removal of obsolete SIP provisions for a program that EPA no longer implements. This comment is outside the scope of the rulemaking. Comment 12: The commenter stated that the SIP should mandate periodic, data-driven reviews of NOX and ozone trends, with automatic triggers for rule reassessment if air quality indicators worsen or if EPA adopts new ozone standards. Response: See response to Comment 10.

IV. What action is the EPA taking?

The EPA is taking final action to approve Missouri's request to remove 10 CSR 10-6.350 and 10 CSR 10-6.360 from the SIP because the rules are no longer operative.

V. Incorporation by Reference

In this document, the EPA is removing rules that were previously incorporated by reference from the applicable Missouri SIP. In accordance with requirements of 1 CFR 51.5, the EPA is removing 10 CSR 10-6.350 and 10 CSR 10-6.360 as discussed in section II. of this preamble and as set forth below in the proposed revision to 40 CFR part 52.

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, 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) [[Page 39130]] 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 October 14, 2025. 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, Incorporation by reference, and Ozone. Dated: July 31, 2025. 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 0