SUPPLEMENTARY INFORMATION:

Table of Contents

I. Obtaining Information and Submitting Comments

II. Rulemaking Procedure

III. Background

IV. Plain Writing

V. National Environmental Policy Act: Environmental Assessment and Proposed Finding of No Significant Impact

VI. Paperwork Reduction Act

VII. Executive Orders

VIII. Availability of Documents

I. Obtaining Information and Submitting Comments

A. Obtaining Information

Please refer to Docket ID NRC-2026-2377 when contacting the NRC about the availability of information for this action. You may obtain publicly available information related to this action by any of the following methods:

• Federal Rulemaking Website: Go to www.regulations.gov and search for Docket ID NRC-2026-2377.
• NRC's Agencywide Documents Access and Management System (ADAMS): You may obtain publicly available documents online in the ADAMS Public Documents collection at www.nrc.gov/​reading-rm/​adams.html. To begin the search, select “Begin ADAMS Public Search.” For problems with ADAMS, please contact the NRC's Public Document Room (PDR) reference staff at 1-800-397-4209, 301-415-4737, or by email to pdr.resource@nrc.gov. For the convenience of the reader, instructions about obtaining materials referenced in this document are provided in the “Availability of Documents” section.
• NRC's PDR: The PDR, where you may examine and order copies of publicly available documents, is open by appointment. To make an appointment to visit the PDR, please send an email to PDR.Resource@nrc.gov or call 1-800-397-4209 or 301-415-4737, between 8 a.m. and 4 p.m. eastern time, Monday through Friday, except Federal holidays.

B. Submitting Comments

The NRC encourages electronic comment submission through the Federal Rulemaking Website ( www.regulations.gov). Please include Docket ID NRC-2026-2377 in your comment submission.

The NRC cautions you not to include identifying or contact information that you do not want to be publicly disclosed in your comment submission. The NRC will post all comment submissions at www.regulations.gov as well as enter the comment submissions into ADAMS. The NRC does not routinely edit comment submissions to remove identifying or contact information.

If you are requesting or aggregating comments from other persons for submission to the NRC, then you should inform those persons not to include identifying or contact information that they do not want to be publicly disclosed in their comment submission. Your request should state that the NRC does not routinely edit comment submissions to remove such information before making the comment submissions available to the public or entering the comment into ADAMS.

II. Rulemaking Procedure

Because the NRC considers this action to be non-controversial, the NRC is publishing this proposed rule concurrently with a direct final rule in the Rules and Regulations section of this issue of the Federal Register . The direct final rule will become effective on December 28, 2026. However, if the NRC receives significant adverse comments by November 13, 2026, then the NRC will publish a document that withdraws the direct final rule. If the direct final rule is withdrawn, the NRC will address the comments in a subsequent final rule. Absent significant modifications to the proposed revisions requiring republication, the NRC will not initiate a second comment period on this action in the event the direct final rule is withdrawn.

A significant adverse comment is a comment where the commenter explains why the rule would be inappropriate, including challenges to the rule's underlying premise or approach, or would be ineffective or unacceptable without a change. A comment is adverse and significant if:

(1) The comment opposes the rule and provides a reason sufficient to require a substantive response in a notice-and-comment process. For example, a substantive response is required when:

(a) The comment causes the NRC to reevaluate (or reconsider) its position or conduct additional analysis;

(b) The comment raises an issue serious enough to warrant a substantive response to clarify or complete the record; or

(c) The comment raises a relevant issue that was not previously addressed or considered by the NRC.

(2) The comment proposes a change or an addition to the rule, and it is apparent that the rule would be ineffective or unacceptable without incorporation of the change or addition.

(3) The comment causes the NRC to make a change (other than editorial) to the rule.

For procedural information and the regulatory analysis, see the direct final rule published in the Rules and Regulations section of this issue of the Federal Register .

III. Background

The NRC originally approved the AP1000 design certification in a final rule published on January 27, 2006 (71 FR 4464). On December 30, 2011 (76 FR 82079), the NRC published a final rule amending appendix D, “Design Certification Rule for the AP1000 Design,” to part 52, “Licenses, Certifications, and Approvals for ( printed page 65135) Nuclear Power Plants,” of title 10 of the Code of Federal Regulations (10 CFR) to incorporate AP1000 Design Control Document (DCD), Revision 19, APP-GW-GL-702, dated June 13, 2011. On September 22, 2021 (86 FR 52593), the NRC published a direct final rule extending the duration of the AP1000 design certification by five years, with an effective date of December 6, 2021.

On July 2, 2025 (90 FR 28869), the NRC amended its regulations to replace the 15-year duration of design certifications with a 40-year duration, both for existing design certifications currently in effect and generically for future design certifications, including renewals. The NRC did not change the date of issuance or renewal for existing design certifications but changed their expiration dates based on the most recent date of issuance or renewal. The current AP1000 design certification expires on February 27, 2046.

On February 10, 2012, the NRC issued combined licenses (COLs) to Southern Nuclear Operating Company (SNC) for the Vogtle Electric Generating Plant (VEGP) Units 3 and 4 (COLs NPF-91 and NPF-92). During the licensing, construction, and operation of VEGP Units 3 and 4, SNC submitted over 180 license amendment requests (LARs) to the NRC addressing design changes, construction-discovered issues, and operational refinements. The NRC reviewed and approved these LARs through safety evaluations for each approved amendment. In addition, SNC implemented numerous Tier 2 departures under the section VIII.B.5 of appendix D to 10 CFR part 52 change process that did not require prior NRC approval. The VEGP licensing process also resolved the COL action items identified in DCD Revision 19 with site-specific design details, operational program descriptions, and as-built information. The VEGP Unit 3 entered commercial operation on July 31, 2023, and Unit 4 did so on April 29, 2024.

In SECY-26-0034, “NRC Regulatory Pathways and Licensing Readiness for Near Term Large Light-Water Reactor Deployment,” dated March 9, 2026, the NRC staff informed the Commission, among other things, that it anticipated submission of the Westinghouse Electric Company LLC (Westinghouse) application to update and renew the AP1000 design certification. The NRC staff also informed the Commission of its plan to incorporate the as-built changes incorporated into VEGP Units 3 and 4, previously approved safety findings, and lessons learned into a revised AP1000 design certification. The NRC's verification review determined that no new changes were incorporated into AP1000 DCD Revision 20 that require additional technical review, and that all changes incorporated into the AP1000 DCD Revision 20 were either previously reviewed and approved by the NRC or were incorporated using a process that does not require NRC approval. Therefore, the NRC is using the direct final rule process to update appendix D to 10 CFR part 52 to include AP1000 DCD Revision 20. This renewal would improve regulatory clarity, avoid unnecessary re-review, and streamline future AP1000 licensing activities by providing applicants with an updated, standardized design basis. The NRC is amending appendix D to 10 CFR part 52 to include AP1000 DCD Revision 20. The NRC is also retaining the incorporation by reference of AP1000 DCD Revision 19 in appendix D to 10 CFR part 52 because several combined license holders were licensed to AP1000 Revision 19 and the incorporation of the AP1000 DCD Revision 19 in appendix D to 10 CFR part 52 remains part of the licensing basis for those combined license holders. Applicants could reference either revision in future applications.

While 10 CFR 52.63(a) imposes restrictive limits on the types of changes that may be made while a design certification rule is in effect, 10 CFR 52.59(c) allows a design certification renewal applicant greater flexibility in seeking changes to the design certification. Thus, a design certification renewal application that includes amendments to a certified design is not required to address the criteria in 10 CFR 52.63, “Finality of standard design certifications.” However, if the amendment request entails such an extensive change to the design certification that an essentially new standard design is being proposed, 10 CFR 52.59(c) provides that an application for a design certification must be filed. The AP1000 amendment request does not propose an essentially new standard design.

The NRC is amending the design certification for the AP1000 standard plant design to renew the AP1000 design certification for 40 years from the effective date of the direct final rule. The NRC determined the submitted application for incorporation by reference of DCD Revision 20 into appendix D to 10 CFR part 52 is acceptable. Further, the Commission granted an exemption from 10 CFR 52.57(a) to allow renewal more than 36 months before expiration of the current design certification rule (91 FR 40596; July 2, 2026). The requirements of 10 CFR 52.55, “Duration of certification,” govern the duration of a design certification and the effect of timely renewal. The AP1000 design certification rule does not expire until 2046.

The NRC is amending section VIII.B.6 of appendix D to 10 CFR part 52 to incorporate the alternative change process that was previously reviewed and approved for Vogtle Units 3 and 4 into appendix D to 10 CFR part 52. The license amendments and exemptions included in AP1000 DCD Revision 20 include a previously reviewed and approved change process for Tier 2* information. On December 21, 2017, SNC submitted LAR-17-037, and an associated exemption request, seeking changes to the Vogtle Units 3 and 4 COLs to add a license condition that would apply the change process for Tier 2 information for a proposed departure from Tier 2* information provided that specific criteria are not met. If one of the criteria were met for the proposed departure, then the proposed departure would continue to require prior NRC approval. On September 20, 2018, the NRC granted the amendments and exemptions to Vogtle Units 3 and 4 that effectively replaced the Tier 2* change process with an alternative process (reflected in a license condition) that applied the Tier 2 change process along with nine additional criteria to determine whether a license amendment was required. Inclusion of this change process in section VIII.B.6 of appendix D to 10 CFR part 52 promotes regulatory efficiency by eliminating the need for unnecessary licensing actions for applicants referencing either AP1000 DCD Revision 19 or AP1000 DCD Revision 20.

IV. Plain Writing

The Plain Writing Act of 2010 (Pub. L. 111-274) requires Federal agencies to write documents in a clear, concise, and well-organized manner. The NRC has written this document to be consistent with the Plain Writing Act as well as the Presidential Memorandum, “Plain Language in Government Writing,” published June 10, 1998 (63 FR 31885). The NRC requests comment on this proposed rule with respect to clarity and effectiveness of the language used.

V. National Environmental Policy Act: Environmental Assessment and Proposed Finding of No Significant Impact

The NRC has determined under the National Environmental Policy Act of 1969, as amended (NEPA), and the NRC's regulations in subpart A, “National Environmental Policy Act—Regulations Implementing Section 102(2),” of 10 CFR part 51, ( printed page 65136) “Environmental Protection Regulations for Domestic Licensing and Related Regulatory Functions,” that this proposed rule, if issued, would not be a major Federal action significantly affecting the quality of the human environment and, therefore, an environmental impact statement is not required. The NRC's generic determination in this regard, reflected in 10 CFR 51.32(b)(1), is based upon the following considerations: (1) A design certification rule does not authorize the siting, construction, or operation of a facility referencing any particular design, but only codifies a standard design certification in a rule (extending the AP1000 design certification and incorporating changes to the design in this case); (2) the NRC will evaluate the environmental impacts and issue an environmental finding in a Record of Decision as appropriate under NEPA as part of the application for the construction and operation of a facility referencing any particular design certification rule; and (3) comments on the environmental assessment will be limited to the consideration of severe accident mitigation design alternatives as required by 10 CFR 51.30(d). The environmental assessment is available in the companion direct final rule published in the Rules and Regulations section of this issue of the Federal Register . In keeping with Commission policy, that environmental assessment also updates the agency's consideration of severe accident mitigation design alternatives.

VI. Paperwork Reduction Act

This proposed rule does not contain any new or amended collections of information subject to the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.). Existing collections of information were approved by the Office of Management and Budget, control number 3150-0151.

Public Protection Notification

The NRC may not conduct or sponsor, and a person is not required to respond to, a collection of information unless the document requesting or requiring the collection displays a currently valid Office of Management and Budget control number.

VII. Executive Orders

The following are Executive orders that are related to this proposed rule:

A. Executive Order 12866: Regulatory Planning and Review (as amended by E.O. 14215, Ensuring Accountability for All Agencies)

The Office of Information and Regulatory Affairs (OIRA) has determined that this direct final rule is not a significant regulatory action.

B. Executive Order 14154: Unleashing American Energy

The NRC has examined this proposed rule and has determined that it is consistent with the policies and directives outlined in E.O. 14154.

C. Executive Order 14192: Unleashing Prosperity Through Deregulation

This action is determined to be a deregulatory action as defined by E.O. 14192. The AP1000 renewal and amendments will facilitate future reactor licensing by resolving design issues generically, which will lead to shorter and more efficient reviews yielding savings to the agency and future applicants.

D. Executive Order 14267: Reducing Anti-Competitive Regulatory Barriers

E.O. 14267 requires the NRC to identify anti-competitive regulations for recission or modification. The purpose of a design certification rule is to facilitate the licensing process for future applicants that reference the certified design. Therefore, there are no anti-competitive regulatory barriers associated with this rule.

E. Executive Order 14270: Zero-Based Regulatory Budgeting To Unleash American Energy

E.O. 14270, “Zero-Based Regulatory Budgeting to Unleash American Energy,” requires the NRC to insert a conditional sunset date into all new or amended NRC regulations provided the regulations are (1) promulgated under the Atomic Energy Act of 1954, as amended (AEA), the Energy Reorganization Act of 1974, as amended (ERA), or the Nuclear Waste Policy Act of 1982, as amended (NWPA); (2) not statutorily required; and (3) not part of the NRC's permitting regime. The NRC determined that the regulatory changes proposed in this rule are part of the NRC permitting regime as future licensing applicants may reference the AP1000 certified design to obtain operating licenses. Therefore, the NRC views this rulemaking to be outside the scope of E.O. 14270 and did not insert conditional sunset dates for the regulatory changes in this direct final rule.

VIII. Availability of Documents

The documents identified in the following table are available to interested persons through one or more of the following methods, as indicated.

The NRC may post materials related to this document, including public comments, on the Federal rulemaking website at www.regulations.gov under Docket ID NRC-2026-2377. In addition, the Federal rulemaking website allows members of the public to receive alerts when changes or additions occur in a docket folder. To subscribe: (1) navigate to the docket folder (NRC-2026-2377); (2) click the “Subscribe” button; and (3) enter an email address and click on the “Subscribe” button.