# Identification of plan—in part.
**AGENCY:**
Environmental Protection Agency (EPA).
**ACTION:**
Final rule.
**SUMMARY:**
The Environmental Protection Agency (EPA) is taking final action to approve a revision to the Eastern Kern Air Pollution Control District (EKAPCD or “District”) portion of the California State Implementation Plan (SIP). This revision concerns emissions of oxides of nitrogen (NO <sub>X</sub> ) from Portland cement kilns. We are approving a local rule that regulates these emission sources under the Clean Air Act (CAA or “Act”).
**DATES:**
This rule is effective May 18, 2026.
**ADDRESSES:**
The EPA has established a docket for this action under Docket ID No. EPA-R09-OAR-2025-0058. 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, *e.g.,* 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 availability information. If you need assistance in a language other than English or if you are a person with a disability who needs a reasonable accommodation at no cost to you, please contact the person identified in the *FOR FURTHER INFORMATION CONTACT* section.
**FOR FURTHER INFORMATION CONTACT:**
Elijah Gordon, EPA Region IX, 75 Hawthorne St., San Francisco, CA 94105; telephone number: (415) 972-3158; email address: *[email protected].*
**SUPPLEMENTARY INFORMATION:**
Throughout this document, “we,” “us,” and “our” refer to the EPA.
**Table of Contents**
I. Proposed Action
II. Public Comments and EPA Responses
III. EPA Action
IV. Incorporation by Reference
V. Statutory and Executive Order Reviews
**I. Proposed Action**
On June 4, 2025 (90 FR 23653), the EPA proposed to approve the following rule into the California SIP.
| Local agency | Rule No. | Rule title | Amended | Submitted |
| --- | --- | --- | --- | --- |
| EKAPCD | 425.3 | Portland Cement Kilns (Oxides of Nitrogen) | 11/13/2024 | 12/12/2024 |
We proposed to approve this rule because we determined that it complies with the relevant CAA requirements. Our proposed action contains more information on the rule and our evaluation.
**II. Public Comments and EPA Responses**
The EPA's proposed action provided a 30-day public comment period. During this period, we received no comments.
**III. EPA Action**
No comments were submitted. Therefore, as authorized in section 110(k)(3) of the Clean Air Act, the EPA is approving this rule into the California SIP. The November 13, 2024 version of Rule 425.3 will replace the previously approved version of this rule in the SIP. This approval resolves all deficiencies forming the basis for our previous limited disapproval in 2023 of the prior version of Rule 425.3. [^1] The deficiencies, which related to exemptions from NO <sub>X</sub> emission limitations, have been remedied by replacing the exemptions during startup and shutdown periods with alternative NO <sub>X</sub> emission limits and removing the exemption during breakdown conditions. This action also permanently terminates all sanctions clocks and FIP clocks triggered by our June 5, 2023 limited disapproval action.
[^1] 88 FR 36479 (June 5, 2023).
**IV. Incorporation by Reference**
In this rule, 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 EKAPCD Rule 425.3, “Portland Cement Kilns (Oxides of Nitrogen),” amended on November 13, 2024, which regulates emissions of NO <sub>X</sub> from Portland cement kilns. 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 rule of the EPA's approval, and will be incorporated by reference in the next update to the SIP compilation. [^2] The EPA has made, and will continue to make, these documents available through *https://www.regulations.gov* and at the EPA Region IX Office (please contact the person identified in the *FOR FURTHER INFORMATION CONTACT* section of this preamble for more information).
[^2] 62 FR 27968 (May 22, 1997).
**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 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 under Executive Order 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 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).
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 June 15, 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 CAA section 307(b)(2).)
**List of Subjects in 40 CFR Part 52**
Environmental protection, Air pollution control, Incorporation by reference, Intergovernmental relations, Nitrogen oxides, Ozone, Reporting and recordkeeping requirements.
Dated: April 3, 2026.
Michael Martucci,
Acting Regional Administrator, Region IX.
For the reasons stated in the preamble, the Environmental Protection Agency amends part 52, chapter I, title 40 of the Code of Federal Regulations as follows:
**PART 52—APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS**
**40 CFR Part 52**
1. The authority citation for Part 52 continues to read as follows:
**Authority:**
42 U.S.C. 7401 *et seq.*
**Subpart F—California**
**40 CFR Part 52**
2. Amend § 52.220a, paragraph (c), under the subheading “Table 10—EPA-Approved Eastern Kern Air Pollution Control District Regulations; Kern County Air Pollution Control District Regulations,” by revising the entry for “425.3,” to read as follows:
§ 52.220a
(c) * * *
| District | Title/subject | State effective date | EPA approval date | Additional |
| --- | --- | --- | --- | --- |
| | | | | |
| * * * * * * * | | | | |
| 425.3 | Portland Cement Kilns (Oxides of Nitrogen) | November 13, 2024 | 4/16/2026, 91 FR [INSERT
PAGE WHERE THE DOCUMENT BEGINS] | Submitted on December 12, 2024. |
| | | | | |
| * * * * * * * | | | | |