ML25351A015

Issuance of Amendment to Increase Flexibility in Mode Restraints

ML25351A015
Person / Time
Site:	Vogtle
Issue date:	12/30/2025
From:	John Lamb NRC/NRR/DORL/LPL2-1
To:	Coleman J Southern Nuclear Operating Co
Lamb J, NRR/DORL/LPL2-1
References
EPID L-2024-LLA-0171
Download: ML25351A015 (0)

Text

December 30, 2025 Jamie Coleman Regulatory Affairs Director Southern Nuclear Operating Company, Inc.

3535 Colonnade Parkway, Bin N-274-EC Birmingham, AL 35243

SUBJECT:

VOGTLE ELECTRIC GENERATING PLANT, UNITS 3 AND 4 ISSUANCE OF AMENDMENT TO INCREASE FLEXIBILITY IN MODE RESTRAINTS (EPID L-2024-LLA-0171)

Dear Ms. Coleman:

In response to your application dated December 19, 2024, as supplemented by letters dated October 31 and December 18, 2025, the U.S. Nuclear Regulatory Commission (NRC) has issued the enclosed Amendment Nos. 210 and 208 to Combined License (COL) Nos. NPF-91 and NPF-92 for Vogtle Electric Generating Plant (Vogtle), Units 3 and 4, respectively. The amendments revise the technical specifications (TSs) to increase flexibility in mode restraints.

The proposed changes are similar to those described in Technical Specification Task Force (TSTF) 359, Revision 9, Increased Flexibility in Mode Restraints, with changes similar to those identified in TSTF-529, Revision 4, Clarify Use and Application Rules, for Limiting Condition for Operation (LCO) 3.0.4.

A copy of the related Safety Evaluation, which includes the NRC staffs evaluation of the amendment, is enclosed. The notice of issuance of the amendment documents included in this letter will be published in the Federal Register.

If you have questions, please contact me at 301-415-3100 or John.Lamb@nrc.gov.

Sincerely,

/RA/

John G. Lamb, Senior Project Manager Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos.: 52-025 and 52-026

Enclosures:

1. Amendment No. 210 to Vogtle, Unit 3, COL

2. Amendment No. 208 to Vogtle, Unit 4, COL

3. Safety Evaluation cc: Listserv

SOUTHERN NUCLEAR OPERATING COMPANY, INC.

GEORGIA POWER COMPANY OGLETHORPE POWER CORPORATION MEAG POWER SPVM, LLC MEAG POWER SPVJ, LLC MEAG POWER SPVP, LLC CITY OF DALTON, GEORGIA VOGTLE ELECTRIC GENERATING PLANT, UNIT 3 DOCKET NO.52-025 AMENDMENT TO FACILITY COMBINED LICENSE Amendment No. 210 License No. NPF-91

1.

The Nuclear Regulatory Commission (the Commission) has found that:

A.

The application for amendment by Southern Nuclear Operating Company (SNC),

dated December 19, 2024, as supplemented by letters dated October 31 and December 18, 2025, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act) and the Commissions regulations set forth in 10 CFR Chapter I; B.

The facility will be constructed and will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C.

There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commissions regulations; D.

The issuance of this amendment will not be inimical to the common defense and security or the health and safety of the public; and E.

The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commissions regulations, and all applicable requirements have been satisfied.

2.

Accordingly, the license is amended by changes to Appendix A, Technical Specifications, of the facility Combined License as indicated in the attachment to this license amendment. Paragraph 2.D(8) of facility Combined License No. NPF-91 is hereby amended to read as follows:

(8) Incorporation The Technical Specifications, Environmental Protection Plan, in Appendices A and B, respectively of this license, as revised through Amendment No. 210, are hereby incorporated into this license.

3.

This license amendment is effective as of the date of its issuance and shall be implemented within 90 days of the date of issuance. Implementation of the amendment shall include updating the Updated Final Safety Analysis Report (UFSAR) in accordance with 10 CFR 50.71 (e). The UFSAR update shall include a statement that the licensee shall implement the changes to the outage risk assessment monitoring procedure and the shutdown defense-in-depth software tool as described in the responses to Requests for Additional Information (RAI) in the letter dated October 31, 2025 (ML25304A235).

FOR THE NUCLEAR REGULATORY COMMISSION:

Michael Markley, Chief Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Date of Issuance: December 30, 2025

Attachment:

Page 4 of the facility Combined License and affected pages of Appendix A of the facility Combined License SHAWN WILLIAMS Digitally signed by SHAWN WILLIAMS Date: 2025.12.30 12:04:12 -05'00'

SOUTHERN NUCLEAR OPERATING COMPANY, INC.

GEORGIA POWER COMPANY OGLETHORPE POWER CORPORATION MEAG POWER SPVM, LLC MEAG POWER SPVJ, LLC MEAG POWER SPVP, LLC CITY OF DALTON, GEORGIA VOGTLE ELECTRIC GENERATING PLANT, UNIT 4 DOCKET NO.52-026 AMENDMENT TO FACILITY COMBINED LICENSE Amendment No. 208 License No. NPF-92

1.

The Nuclear Regulatory Commission (the Commission) has found that:

A.

The application for amendment by Southern Nuclear Operating Company (SNC),

dated December 20, 2024, as supplemented by letter dated October 31 and December 18, 2025, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act) and the Commissions regulations set forth in 10 CFR Chapter I; B.

The facility will be constructed and will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C.

There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commissions regulations; D.

The issuance of this amendment will not be inimical to the common defense and security or the health and safety of the public; and E.

The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commissions regulations, and all applicable requirements have been satisfied.

2.

Accordingly, the license is amended by changes to Appendix A, Technical Specifications, of the facility Combined License as indicated in the attachment to this license amendment. Paragraph 2.D(8) of facility Combined License No. NPF-92 is hereby amended to read as follows:

(8) Incorporation The Technical Specifications and Environmental Protection Plan in Appendices A and B, respectively, of this license, as revised through Amendment No. 208, are hereby incorporated into this license.

3.

This license amendment is effective as of the date of its issuance and shall be implemented within 90 days of the date of issuance. Implementation of the amendment shall include updating the Updated Final Safety Analysis Report (UFSAR) in accordance with 10 CFR 50.71 (e). The UFSAR update shall include a statement that the licensee shall implement the changes to the outage risk assessment monitoring procedure and the shutdown defense-in-depth software tool as described in the responses to Requests for Additional Information (RAI) in the letter dated October 31, 2025 (ML25304A235).

FOR THE NUCLEAR REGULATORY COMMISSION:

Michael Markley, Chief Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Date of Issuance: December 30, 2025

Attachment:

Page 4 of the facility Combined License and affected pages of Appendix C of the facility Combined License SHAWN WILLIAMS Digitally signed by SHAWN WILLIAMS Date: 2025.12.30 12:04:45 -05'00'

ATTACHMENT TO LICENSE AMENDMENT NOS. 210 AND 208 TO FACILITY COMBINED LICENSE NOS. NPF-91 AND NPF-92 DOCKET NOS.52-025 AND 52-026 Replace the following pages of the facility Combined License Nos. NPF-91 and NPF-92 with the attached revised pages. The revised pages are identified by amendment number and contain marginal lines indicating the areas of change.

Facility Combined License No. NPF-91 REMOVE INSERT 4

4 Facility Combined License No. NPF-92 REMOVE INSERT 4

4 Appendix A to Facility Combined License Nos. NPF-91 and NPF-92 REMOVE INSERT 3.0-1 3.0-1 3.0-2 3.0-2 3.0-4 3.0-4 3.3.17-1 3.3.17-1 3.3.18-1 3.3.18-1 3.4.9-2 3.4.9-2 3.4.10-1 3.4.10-1 3.4.14-1 3.4.14-1

D.

The license is subject to, and SNC shall comply with, the conditions specified and incorporated below:

(1)

Changes during Construction - Removed by Amendment No. 202 (2)

Pre-operational Testing - Removed by Amendment Nos. 192 and 202 (3)

Nuclear Fuel Loading and Pre-critical Testing - Removed by Amendment Nos. 192 and 202 (4)

Initial Criticality and Low-Power Testing - Removed by Amendment No. 202 (5)

Power Ascension Testing - Removed by Amendment No. 202 (6)

Maximum Power Level (7)

(8)

SNC is authorized to operate the facility at steady state reactor core power levels not to exceed 3400 MW thermal (100-percent thermal power), as described in the UFSAR, in accordance with the conditions specified herein.

Reporting Requirements - Removed by Amendment No. 202 Incorporation The Technical Specifications and Environmental Protection Plan in Appendices A and B, respectively, of this license, as revised through Amendment No. 210, are hereby incorporated into this license.

(9)

Technical Specifications - Removed by Amendment No. 202 (10)

Operational Program Implementation - Removed by Amendment No. 202 (11)

Operational Program Implementation Schedule - Removed by Amendment No.202 (12)

Site-and Unit-specific Conditions - Removed by Amendment No. 202

[Blank Pages 5 through 14 removed by Amendment No. 202.]

4 Amendment No. 210

D.

The license is subject to, and SNC shall comply with, the conditions specified and incorporated below:

(1)

Changes during Construction - Removed by Amendment No. 199 (2)

Pre-operational Testing - Removed by Amendment Nos. 194 and 199 (3)

Nuclear Fuel Loading and Pre-critical Testing - Removed by Amendment Nos. 194 and 199 (4)

Initial Criticality and Low-Power Testing - Removed by Amendment No. 199 (5)

Power Ascension Testing - Removed by Amendment No. 199 (6)

Maximum Power Level (7)

(8)

SNC is authorized to operate the facility at steady state reactor core power levels not to exceed 3400 MW thermal (100-percent thermal power), as described in the UFSAR, in accordance with the conditions specified herein.

Reporting Requirements - Removed by Amendment No. 199 Incorporation The Technical Specifications and Environmental Protection Plan in Appendices A and B, respectively, of this license, as revised through Amendment No. 208, are hereby incorporated into this license.

(9)

Technical Specifications - Removed by Amendment No. 199 (10)

Operational Program Implementation - Removed by Amendment No. 199 (11)

Operational Program Implementation Schedule - Removed by Amendment No. 199 (12)

Site-and Unit-specific Conditions - Removed by Amendment No. 199

[Blank Pages 5 through 14 removed by Amendment No. 199.]

4 Amendment No. 208

Technical Specifications LCO Applicability 3.0 VEGP Units 3 and 4 3.0 - 1 Amendment No. 210 (Unit 3)

Amendment No. 208 (Unit 4) 3.0 LIMITING CONDITIONS FOR OPERATION (LCO) APPLICABILITY LCO 3.0.1 LCOs shall be met during the MODES or other specified conditions in the Applicability, except as provided in LCO 3.0.2 and LCO 3.0.7.

LCO 3.0.2 Upon discovery of a failure to meet an LCO, the Required Actions of the associated Conditions shall be met, except as provided in LCO 3.0.5 and 3.0.6.

If the LCO is met, or is no longer applicable prior to expiration of the specified Completion Time(s), completion of the Required Action(s) is not required, unless otherwise stated.

LCO 3.0.3 When an LCO is not met and the associated ACTIONS are not met, an associated ACTION is not provided, or if directed by the associated ACTIONS, the unit shall be placed in a MODE or other specified condition in which the LCO is not applicable. Action shall be initiated within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to place the unit, as applicable, in:

a.

MODE 3 within 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br />; and b.

MODE 4 within 13 hours1.50463e-4 days <br />0.00361 hours <br />2.149471e-5 weeks <br />4.9465e-6 months <br />; and c.

MODE 5 within 37 hours4.282407e-4 days <br />0.0103 hours <br />6.117725e-5 weeks <br />1.40785e-5 months <br />.

Exceptions to this Specification are stated in the individual Specifications.

Where corrective measures are completed that permit operation in accordance with the LCO or ACTIONS, completion of the actions required by LCO 3.0.3 is not required.

LCO 3.0.3 is only applicable in MODES 1, 2, 3, and 4.

LCO 3.0.4 When an LCO is not met, entry into a MODE or other specified condition in the Applicability shall only be made:

a.

When the associated Actions to be entered permit continued operation in the MODE or other specified condition in the Applicability for an unlimited period of time; or b.

After performance of a risk assessment addressing inoperable systems and components, consideration of the results, determination of the acceptability of entering the MODE or other specified condition in the Applicability, and establishment of risk management actions, if appropriate (exceptions to this Specification are stated in the individual Specification); or

Technical Specifications LCO Applicability 3.0 VEGP Units 3 and 4 3.0 - 2 3.0 LCO Applicability LCO 3.0.4 (continued) c.

When an allowance is stated in the individual value, parameter, or other Specification.

This Specification shall not prevent changes in MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or that are part of a shutdown of the unit.

LCO 3.0.5 Equipment removed from service or declared inoperable to comply with ACTIONS may be returned to service under administrative control solely to perform testing required to demonstrate its OPERABILITY or the OPERABILITY of other equipment. This is an exception to LCO 3.0.2 for the system returned to service under administrative control to perform the test required to demonstrate OPERABILITY.

LCO 3.0.6 When a supported system LCO is not met solely due to a support system LCO not being met, the Conditions and Required Actions associated with this supported system are not required to be entered. Only the support system LCO ACTIONS are required to be entered. This is an exception to LCO 3.0.2 for the supported system. In this event, additional evaluations and limitations may be required in accordance with Specification 5.5.7, Safety Function Determination Program (SFDP). If a loss of safety function is determined to exist by this program, the appropriate Conditions and Required Actions of the LCO in which the loss of safety function exists are required to be entered.

When a support systems Required Action directs a supported system to be declared inoperable or directs entry into Conditions and Required Actions for a supported system, the applicable Conditions and Required Actions shall be entered in accordance with LCO 3.0.2.

LCO 3.0.7 Test Exception LCOs 3.1.8 and 3.1.10 allow specified Technical Specification (TS) requirements to be changed to permit performance of special tests and operations. Unless otherwise specified, all other TS requirements remain unchanged. Compliance with Test Exception LCOs is optional. When a Test Exception LCO is desired to be met but is not met, the ACTIONS of the Test Exception LCO shall be met. When a Test Exception LCO is not desired to be met, entry into a MODE or other specified condition in the Applicability shall be made in accordance with the other applicable Specifications.

Amendment No. 210 (Unit 3)

Amendment No. 208 (Unit 4)

Technical Specifications SR Applicability 3.0 VEGP Units 3 and 4 3.0 - 4 3.0 SR Applicability SR 3.0.4 Entry into a MODE or other specified condition in the Applicability of an LCO shall only be made when the LCOs Surveillances have been met within their specified Frequency, except as provided by SR 3.0.3. When an LCO is not met due to Surveillances not having been met, entry into a MODE or other specified condition in the Applicability shall only be made in accordance with LCO 3.0.4.

This provision shall not prevent entry into MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or that are part of a shutdown of the unit.

Amendment No. 210 (Unit 3)

Amendment No. 208 (Unit 4)

Technical Specifications PAM Instrumentation 3.3.17 VEGP Units 3 and 4 3.3.17 - 1 3.3 INSTRUMENTATION 3.3.17 Post Accident Monitoring (PAM) Instrumentation LCO 3.3.17 The PAM instrumentation for each Function in Table 3.3.17-1 shall be OPERABLE.

APPLICABILITY:

MODES 1, 2, and 3.

ACTIONS

- NOTE -

Separate Condition entry is allowed for each Function.

CONDITION REQUIRED ACTION COMPLETION TIME A.

One or more Functions with one required channel inoperable.

A.1 Restore required channel to OPERABLE status.

30 days B.

Required Action and associated Completion Time of Condition A not met.

B.1 Initiate action in accordance with Specification 5.6.5.

Immediately C.

One or more Functions with two required channels inoperable.

C.1 Restore one channel to OPERABLE status.

7 days D.

Required Action and associated Completion Time of Condition C not met.

D.1 Enter the Condition referenced in Table 3.3.17-1 for the channel.

Immediately E.

As required by Required Action D.1 and referenced in Table 3.3.17-1.

E.1 AND E.2 Be in MODE 3.

Be in MODE 4.

6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 12 hours Amendment No. 210 (Unit 3)

Amendment No. 208 (Unit 4)

Technical Specifications RSW 3.3.18 VEGP Units 3 and 4 3.3.18 - 1 3.3 INSTRUMENTATION 3.3.18 Remote Shutdown Workstation (RSW)

LCO 3.3.18 The RSW shall be OPERABLE.

APPLICABILITY:

MODES 1, 2, and 3.

MODE 4 with Reactor Coolant System (RCS) average temperature (Tavg) 350°F.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.

RSW inoperable.

A.1 Restore to OPERABLE status.

30 days B.

Required Action and associated Completion Time not met.

B.1 AND B.2 Be in MODE 3.

Be in MODE 4 with Tavg < 350°F.

6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 12 hours SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.3.18.1 Verify each required transfer switch is capable of performing the required function.

24 months SR 3.3.18.2 Verify the RSW communicates indication and controls with Division A, B, C and D of the Protection and Safety Monitoring System (PMS).

24 months SR 3.3.18.3 Verify the OPERABILITY of the RSW hardware and software.

24 months Amendment No. 210 (Unit 3)

Amendment No. 208 (Unit 4)

Technical Specifications RCS Leakage Detection Instrumentation 3.4.9 VEGP Units 3 and 4 3.4.9 - 2 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.

One required containment sump channel inoperable.

A.1 Restore two containment sump channels to OPERABLE status.

14 days B.

Two required containment sump channels inoperable.

B.1

- NOTE -

Not required until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after establishment of steady state operation.

Perform SR 3.4.7.1.

Once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> AND B.2 Restore one containment sump channel to OPERABLE status.

72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> C.

Containment atmosphere F18 particulate monitor inoperable.

C.1.1 Analyze grab samples of containment atmosphere.

Once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> OR C.1.2

- NOTE -

Not required until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after establishment of steady state operation.

Perform SR 3.4.7.1.

Once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> AND C.2 Restore containment atmosphere F18 particulate monitor to OPERABLE status.

30 days Amendment No. 210 (Unit 3)

Amendment No. 208 (Unit 4)

Technical Specifications RCS Specific Activity 3.4.10 VEGP Units 3 and 4 3.4.10 - 1 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.10 RCS Specific Activity LCO 3.4.10 The specific activity of the reactor coolant shall be within limits.

APPLICABILITY:

MODES 1 and 2.

MODE 3 with RCS average temperature (Tavg) 500°F.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.

DOSE EQUIVALENT I-131 > 1.0 Ci/gm.

- NOTE -

LCO 3.0.4.c is applicable.

A.1 Verify DOSE EQUIVALENT I-131 60 Ci/gm.

Once per 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> AND A.2 Restore DOSE EQUIVALENT I-131 to within limit.

48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> B.

DOSE EQUIVALENT XE-133 > 280 Ci/gm.

B.1 Be in MODE 3 with Tavg

< 500°F.

6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> C.

Required Action and associated Completion Time of Condition A not met.

OR DOSE EQUIVALENT I-131 > 60 Ci/gm.

C.1 Be in MODE 3 with Tavg

< 500°F.

6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> Amendment No. 210 (Unit 3)

Amendment No. 208 (Unit 4)

Technical Specifications LTOP 3.4.14 VEGP Units 3 and 4 3.4.14 - 1 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.14 Low Temperature Overpressure Protection (LTOP)

LCO 3.4.14 At least one of the following overpressure protection methods shall be OPERABLE, with the accumulators isolated:

a.

Two Normal Residual Heat Removal System (RNS) suction relief valves and Chemical and Volume Control System (CVS) makeup line containment isolation valve, CVS-PL-V091, closed; or b.

The RCS depressurized and an RCS vent of 4.15 square inches.

- NOTE -

Accumulator isolation is only required when accumulator pressure is greater than or equal to the maximum RCS pressure for the existing RCS cold leg temperature allowed by the P/T limit curves provided in the PTLR.

APPLICABILITY:

MODE 4 when any cold leg temperature is 275°F, MODE 5, MODE 6 when the reactor vessel head is on.

ACTIONS

---

NOTE----------------------------------------------------------

LCO 3.0.4.b is not applicable.

CONDITION REQUIRED ACTION COMPLETION TIME A.

An accumulator not isolated when the accumulator pressure is greater than or equal to the maximum RCS pressure for existing cold leg temperature allowed in the PTLR.

A.1 Isolate affected accumulator.

1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> Amendment No. 210 (Unit 3)

Amendment No. 208 (Unit 4)

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NOS. 210 AND 208 TO THE COMBINED LICENSE NOS. NPF-91 AND NPF-92 SOUTHERN NUCLEAR OPERATING COMPANY, INC.

GEORGIA POWER COMPANY OGLETHORPE POWER CORPORATION MEAG POWER SPVM, LLC MEAG POWER SPVJ, LLC MEAG POWER SPVP, LLC CITY OF DALTON, GEORGIA VOGTLE ELECTRIC GENERATING PLANT, UNITS 3 AND 4 DOCKET NOS.52-025 AND 52-026

1.0 INTRODUCTION

By letter dated December 19, 2024 (Agencywide Documents Access and Management System Accession No. ML24354A169), as supplemented by letters dated October 31 and December 18, 2025 (ML25304A235 and ML25353A427, respectively), Southern Nuclear Operating Company (SNC, the licensee) requested that the U.S. Nuclear Regulatory Commission (NRC) amend Vogtle Electric Generating Plant (Vogtle), Units 3 and 4 Combined License (COL) Nos. NPF-91 and NPF-92, respectively. SNC proposed amending its Vogtle, Units 3 and 4, Appendix A, Technical Specifications (TSs), to increase flexibility in mode restraints.

The proposed amendments are similar to those described in Technical Specification Task Force 359, Revision 9, Increased Flexibility in Mode Restraints, (TSTF-359) with changes similar to those identified in TSTF-529, Revision 4, Clarify Use and Application Rules, for Limiting Condition for Operation (LCO) 3.0.4.

The supplements dated October 31 and December 18, 2025, provided additional information that clarified the application, did not expand the scope of the application as originally noticed, and did not change the NRC staffs original proposed no significant hazards consideration determination as published in the Federal Register on February 18, 2025 (90 FR 9743).

2.0 REGULATORY EVALUATION

2.1 Background

The Standard Technical Specification (STS) for the Westinghouse Advanced Passive 1000 (AP1000) Plants, Revision 0, Volume 1, Specifications was issued in NUREG-2194, dated April 2016 (ML16110A277). The technical specifications (TSs) (ML14100A106) for Vogtle, Units 3 and 4, are based on NUREG-2194. TSTF-359, Revision 9, Increased Flexibility in Mode Restraints, was issued April 28, 2003 (ML031190607). The model safety evaluation (SE) approving TSTF-359 was issued on March 28, 2003 (ML030900056). TSTF-529, Revision 4, Clarify Use and Application Rules, was issued February 29, 2016 (ML16062A271). The model SE approving TSTF-529 was issued on April 21, 2016 (ML16060A440). TSTF-359 and TSTF-529 were not originally approved for the AP-1000 design; therefore, adoption of the TS changes included in TSTF-359 and TSTF-529 required the NRC staff to perform a plant-specific review for Vogtle, Units 3 and 4.

Prior to the approval of TSTF-359, the STS specified that a nuclear power plant could not go to higher modes of operation (i.e., move toward power operation) unless all TS systems, normally required for the higher mode, were operable. This limitation was typically included in LCO 3.0.4 and Surveillance Requirement (SR) 3.0.4 for each plant. LCO 3.0.4 and SR 3.0.4 in the STS stated, in part, that when an LCO or SR is not met, entry into a MODE or other specified condition in the applicability shall not be made except when the associated actions to be entered permit continued operation in the MODE or other specified condition in the applicability for an unlimited period of time. In TSTF-359, the industry stated that this requirement was unnecessarily restrictive and could unduly delay plant startup while considerable resources were used to resolve startup issues that were risk insignificant or low risk. A maintenance activity that takes longer than planned could delay a mode change and adversely impact a utilitys orderly plant startup and return to power operation. The objective of the TS changes in TSTF-359 (and this license amendment request (LAR)) is to provide additional operational flexibility without compromising plant safety.

The Vogtle, Units 3 and 4, TS equivalents to the STS LCO 3.0.4 and SR 3.0.4 are LCO 3.0.4 and SR 3.0.4. The proposed changes in the LAR to the licensees LCO 3.0.4 and SR 3.0.4 mirror those in TSTF-359 and would allow mode changes into a TS condition that has a specific required action and completion time after determining the level of risk is acceptable and implementing appropriate risk management actions. In addition, SNC will utilize the LCO 3.0.4 and SR 3.0.4 allowances only when it determines that there is a reasonable probability that the licensee can restore compliance with the LCO (i.e., the LCO will be met) within the LCO completion time (CT), after the mode change. In addition, the LCO 3.0.4 and SR 3.0.4 allowances can be applied to values and parameters in specifications when explicitly stated in the TS (e.g., non-system/component TS such as: Reactor Coolant System (RCS) Specific Activity). These changes are in addition to the current mode change allowance when a required action has an indefinite completion time.

TSTF-359 included generic risk assessments performed by each of the owners groups as part of the technical justification for the approval of TSTF-359. Since none of the owners groups generic risk assessments that were included in TSTF-359 are applicable to Vogtle, Units 3 and 4s, design, the licensee provided their plant-specific assessment in Attachment 4 of the LAR.

The approach for LCO 3.0.4.b implementation in this LAR is to preclude the use of LCO 3.0.4.b only for higher risk systems and components that are not capable of being adequately assessed by the 10 CFR 50.65(a)(4) procedures and tools. Based on the licensees evaluation in, the LCO 3.0.4 and SR 3.0.4 mode change allowances are not permitted for Low Temperature Overpressure Protection (LCO 3.4.14) in the modes specified in order to protect the integrity of the RCS pressure boundary.

2.2 Proposed Changes 2.2.1 Proposed Changes to LCO 3.0.4 The licensees current LCO 3.0.4:

When an LCO is not met, entry into a MODE or other specified condition in the Applicability shall not be made except when the associated ACTIONS to be entered permit continued operation in the MODE or other specified condition in the Applicability for an unlimited period of time. This Specification shall not prevent changes in MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or are part of a shutdown of the unit.

Exceptions to this Specification are stated in the individual Specifications.

LCO 3.0.4 is only applicable for entry into a MODE or other specified condition in the Applicability in MODES 1, 2, 3, and 4.

The proposed LCO 3.0.4 would state the following:

When an LCO is not met, entry into a MODE or other specified condition in the Applicability shall only be made:

a.

When the associated Actions to be entered permit continued operation in the MODE or other specified condition in the Applicability for an unlimited period of time; or

b.

After performance of a risk assessment addressing inoperable systems and components, consideration of the results, determination of the acceptability of entering the MODE or other specified condition in the Applicability, and establishment of risk management actions, if appropriate (exceptions to this Specification are stated in the individual Specification); or

c.

When an allowance is stated in the individual value, parameter, or other Specification.

This Specification shall not prevent changes in MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or that are part of a shutdown of the unit.

2.2.2 Proposed Changes to Surveillance Requirement (SR) 3.0.4 The licensees current SR 3.0.4 states:

Entry into a MODE or other specified condition in the Applicability of a LCO shall not be made unless the LCOs Surveillances have been met within their specified Frequency. This provision shall not prevent entry into MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or that are part of a shutdown of the unit.

SR 3.0.4 is only applicable for entry into a MODE or other specified condition in the Applicability in MODES 1, 2, 3, and 4.

The proposed SR 3.0.4 would state the following:

Entry into a MODE or other specified condition in the Applicability of an LCO shall only be made when the LCOs Surveillances have been met within their specified Frequency, except as provided by SR 3.0.3. When an LCO is not met due to Surveillances not having been met, entry into a MODE or other specified condition in the Applicability shall only be made in accordance with LCO 3.0.4.

This provision shall not prevent entry into MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or that are part of a shutdown of the unit.

2.2.3 Additional Proposed Changes Technical Specification No.

Description of Change LCO 3.3.17, Post Accident Monitoring (PAM) Instrumentation Actions Note 1 providing an exception to LCO 3.0.4 is deleted.

LCO 3.3.18, Remote Shutdown Workstation (RSW)

The Actions Note providing an exception to LCO 3.0.4 is deleted.

LCO 3.4.9, RCS Leakage Detection Instrumentation The Actions Note providing an exception to LCO 3.0.4 is deleted.

LCO 3.4.10, RCS Specific Activity Action As Note is revised to state that LCO 3.0.4.c is applicable to Dose Equivalent I-131 > 1.0 µCi/gm.

LCO 3.4.14, Low Temperature Overpressure Protection (LTOP)

A new note is added to the Actions that states that LCO 3.0.4.b is not applicable.

Bases for LCO 3.0.4 The existing Vogtle, Units 3 and 4, Bases for LCO 3.0.4 are replaced with TSTF-359 Bases (as modified by TSTF-529) for LCO 3.0.4.

Technical Specification No.

Description of Change Bases for SR 3.0.4 The existing Vogtle, Units 3 and 4, Bases for SR 3.0.4 are replaced with TSTF-359 Bases (as modified by TSTF-529) for SR 3.0.4.

Bases for LCO 3.3.17 The bases are revised to reflect LCO 3.0.4.c allowance consistent with TSTF-359.

Bases for LCO 3.4.9.3 The Bases are revised to reflect deletion of the paragraph in Action f that provided an exception to LCO 3.0.4. Discussion is added to address the application of LCO 3.0.4.b.

Bases for LCO 3.5.3 Discussion is added to address the inapplicability of LCO 3.0.4.b.

Bases for LCO 3.7.1.2 Discussion is added to address the inapplicability of LCO 3.0.4.b.

Bases for LCO 3.8.1.1 Discussion is added to address the inapplicability of LCO 3.0.4.b.

2.3 Regulatory Requirements, Licensing Information, Guidance Documents The NRC staff considered the following regulatory requirements, guidance, and licensing information during its review of the proposed changes:

Regulation 10 CFR 50.36(c) requires TSs to include the following categories: (1) safety limits, limiting safety system settings, and limiting control settings; (2) LCO; (3) SRs; (4) design features; (5) administrative controls; (6) decommissioning; (7) initial notification; and (8) written reports.

Section 50.36(c)(2) of 10 CFR states, in part, that:

Limiting conditions for operation are the lowest functional capability or performance levels of equipment required for safe operation of the facility. When a limiting condition for operation of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial action permitted by the technical specifications until the condition can be met.

Section 50.36(c)(3) of 10 CFR states that:

Surveillance requirements are requirements relating to test, calibration, or inspection to assure that the necessary quality of systems and components is maintained, that facility operation will be within safety limits, and that the limiting conditions for operation will be met.

The NRC staffs guidance for the review of the TSs is in NUREG-0800, Standard Review Plan

[SRP] for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR [Light-Water Reactor] Edition, Chapter 16, Technical Specifications, Revision 3, dated March 2010 (ML100351425).

Section (a)(4) of 10 CFR 50.65, Requirements for monitoring the effectiveness of maintenance at nuclear power plants, (the Maintenance Rule) requires that [b]efore performing maintenance activities (including but not limited to surveillance, post-maintenance testing, and corrective and preventive maintenance), the licensee shall assess and manage the increase in risk that may result from the proposed maintenance activities. The scope of the assessment may be limited to structures, systems, and components that a risk-informed evaluation process has shown to be significant to public health and safety.

Nuclear Utility Management and Resources Council (NUMARC) 93-01, Revision 4F, Industry Guideline for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants, (ML18120A069), Section 11.0, Assessment of Risk Resulting from Maintenance Activities, provides a methodology (endorsed by the NRC in Regulatory Guide(RG) 1.160, Revision 4, Monitoring the Effectiveness of Maintenance at Nuclear Power Plants, (ML18220B281) that is an acceptable approach to manage and assess risk associated with maintenance activities.

3.0 TECHNICAL EVALUATION

The current Vogtle, Units 3 and 4, LCO 3.0.4 allowance is retained in the proposed LCO 3.0.4.a and does not represent a change in risk from the current requirements. The proposed LCO 3.0.4.b allowances apply to systems and components and require a risk assessment prior to utilization to ensure an acceptable level of safety is maintained. The LCO 3.0.4.c allowance applies to parameters and values which have been previously approved by the NRC in a plants specific TSs. In the LAR, the licensee provided a discussion and technical basis for applying LCO 3.0.4.c allowance to LCO 3.4.10, RCS Activity. The TS Bases of LCO 3.0.4 are revised to explain the new allowances and their utilization.

The risk information submitted in support of the proposed changes to TS LCO 3.0.4 and SR 3.0.4 in TSTF-359 included qualitative risk assessments performed by each owners group to identify higher risk systems and components at the various modes of operation, including transitions between modes, as the plant moves upward from the refueling mode of operation toward power operation. The owners groups generic qualitative risk assessments are included as attachments to TSTF-359, Revision 9 (ML031190607). Since none of the owners groups generic risk assessments are applicable to Vogtle, Units 3 and 4s design, the licensee provided its design-specific assessment in Attachment 4 of the LAR. The NRC staffs evaluation of how the implementation of the proposed risk-informed approach, used to justify LCO 3.0.4.b allowances, agrees with the objectives of the guidance outlined in NUMARC 93-01, Revision 4F as endorsed by RG 1.160, Revision 4, is discussed in Section 3.1. Oversight of the risk-informed approach associated with the LCO 3.0.4.b allowances is discussed in Section 3.2 of this safety evaluation.

3.1 Evaluation of Risk Management Both the temporary and cumulative risk of the proposed change is adequately limited. For transition to Modes 1, 2, and 3 or other specified conditions in the Applicability within those Modes, use of the proposed LCO 3.0.4.b involves an assessment using the at-power Probabilistic Risk Assessment (PRA) models (internal events, internal flood, fire) in accordance with station procedures, consistent with implementation of 10 CFR 50.65(a)(4) and NUMARC 93-01. The assessment will account for unavailable equipment and plant conditions. These PRA models are updated on the frequency required by § 50.71 Maintenance of Records, Making of Reports. The cumulative risk is limited by the temporary risk limitations and by the expected low frequency of the proposed operational condition changes with inoperable equipment (Section 3.1.2 of this safety evaluation). Adequate NRC oversight of the licensees ability to use the LCO 3.0.4.b provisions under appropriate circumstances, i.e., to identify risk-significant configurations when entering a higher mode or condition in the applicability of an LCO (Section 3.1.3 of this safety evaluation) is provided by NRC inspection of the licensees implementation of 10 CFR 50.65(a)(4) as applied to the proposed change.

For transition to Modes 4, 5, and 6 or other specified conditions in the Applicability within those Modes, use of LCO 3.0.4.b involves an assessment using the shutdown defense-in-depth tool in accordance with station procedures, consistent with implementation of 10 CFR 50.65(a)(4),

RG 1.160, Revision 4, and NUMARC 91-06. The assessment will account for unavailable equipment and plant conditions. If the assessment determines a key safety function (KSF) will have no available defense-in-depth (Red condition), voluntary entry into the configuration is not permitted, and the mode change is not allowed.

If the assessment determines the KSFs have at least one set of structures, systems and components (SSCs), including supports, (Orange or Yellow condition), then the mode change is allowed provided risk is managed with implementation of appropriate contingency actions.

The NRC staff evaluated the shutdown defense-in-depth tool in the context of passive safety system dependencies and containment closure considerations as illustrated by the Requests for Additional Information (RAI) in the letter dated October 31, 2025. Upon approval of the LAR, SNC shall update the UFSAR by including a statement that the changes to the outage risk assessment monitoring procedure and the shutdown defense-in-depth software tool as described in the responses to RAI in the letter dated October 31, 2025 (ML25304A235) will be implemented. Upon approval of this LAR, the licensee will update its shutdown defense-in-depth tool and the associated software model as stated in the RAI response. The NRC staff finds the shutdown defense-in-depth tool and the associated software tool, as modified by the RAI responses, adequately assess the risk associated with inoperable SSCs in Modes 4, 5, and 6.

3.1.1 Identification of Risk-Important TS Systems and Components A major element that limits the risk of the proposed mode change flexibility is the exclusion of certain systems and associated LCO for the mode change allowance. TSs allow operation in Mode 1 (Power Operation) with specified levels of inoperability for specified times. This provides a benchmark of currently acceptable risk against which to measure any incremental risk inherent in the proposed LCO 3.0.4.b. If a system inoperability accrues risk at a higher rate in one or more of the transition operational conditions than it would in Mode 1, then an upward transition into that mode should not be allowed without demonstration of a high degree of experience and sophistication in risk management. However, the risk management process evaluated in Section 3.1.3 (of this safety evaluation), is adequate.

The importance of most TS systems in mitigating accidents increases as power increases.

However, some TS systems are relatively more important during lower power and shutdown operations, because:

Certain events are peculiar to modes of plant operation other than power operation, Certain events are more probable at modes of plant operation other than power operation, and Some modes of plant operation have less mitigation system capability than power operation.

The risk information submitted in support of the proposed changes to TS LCO 3.0.4 and SR 3.0.4 in TSTF-359 included qualitative risk assessments performed by each owners group to identify higher risk systems and components at the various modes of operation, including transitions between modes, as the plant moves upward from the refueling mode of operation toward power operation. The owners groups generic qualitative risk assessments are included as attachments to TSTF-359, Revision 9 (ML031190607). Since none of the owners groups generic risk assessments are applicable to Vogtle, Units 3 and 4s design, SNC provided its plant--specific assessment in Attachment 4 of the LAR. In Attachment 4, the licensee discusses the qualitative assessment technical approach used and the systems/components subsequently determined to be of higher risk significance. As proposed in the LAR, the higher risk significance systems/components, not to be granted the TS LCO 3.0.4 allowances for the various operational conditions, are those not capable of being adequately assessed by the 10 CFR 50.65(a)(4) procedures and tools.

All owners groups and Vogtle Unit 3 and 4 used a similar systematic approach in their qualitative risk assessments to identify the higher-risk systems in the STS, consisting of the following steps:

Identification of plant conditions (i.e., plant parameters and availability of key mitigation systems) associated with changes in plant modes while returning to power, Identification of key activities that have the potential to impact risk and which are in progress during transitions between modes while the plant is returning to

power, Identification of applicable accident initiating events for each mode or other specified condition in the applicability, and Identification of the higher-risk systems and components by combining the information in the first three steps (qualitative risk assessment).

The risk assessments properly used the results and insights from previous deterministic and probabilistic studies to systematically search for plant conditions in which certain key plant components are more important in mitigating accidents than during operation at power (Mode 1). This search was systematic, taking the following factors into account for the various stages of returning the plant to power:

The status of accident mitigation and normally operating systems, The status of key plant parameters such as reactor coolant system pressure, The key activities that are in progress during transitions between modes which have the potential to impact risk (e.g., the transfer from auxiliary to main feedwater at some PWR plants when Mode 1 is entered),

The applicable accident initiating events for each mode of plant operation, and Design and operational differences among plants or groups of plants.

For its plant-specific risk assessment, SNC utilized a similar approach as that utilized by the Westinghouse Owners Group for the legacy Westinghouse plants in TSTF-359. The following system/component applicable to this LAR was identified as a higher-risk system/component that should be excluded from using LCO 3.0.4.b when the plant is entering a new mode.

System Entering Mode LTOP/PORVs (when used for Low Temperature Overpressure Protection (LTOP))

4, 5, 6 Based on the finding from their qualitative assessment, the LAR proposes to add a note to LCO 3.4.14, Low Temperature Overpressure Protection (LTOP) that states, LCO 3.0.4.b is not applicable. LTOP protection is excluded from LCO 3.0.4.b applicability because it is not within the scope of the licensees shutdown defense-in-depth tool use for a(4) assessments or the AP1000 low power and shutdown PRA developed for design certification. Low Temperature Overpressure Protection is not addressed in NUMARC 91-06. For Modes 4, 5, and 6, the licensee did not add the same note to other identified higher risk systems and components because the licensees defense-in-depth risk assessment tools can adequately assess the risk associated with those systems and components. For Modes 1, 2, and 3, the risk criteria in NUMARC 93-01 would limit the applicability of LCO 3.0.4.b, if the risk exceeded the criteria.

The NRC staffs review of the owners groups qualitative risk assessments found that they are of adequate quality to support the application (i.e., they identify the higher-risk systems and components that should be excluded from the use of LCO 3.0.4.b) associated with entering higher modes of plant operation with equipment inoperable while returning to power. Since the licensee utilized a similar methodology for its plant-specific risk analysis, the NRC staff concludes that the licensees plant-specific risk analysis is of adequate quality to support approval of the LAR.

The licensee proposes to adopt the TSTF-359 wording for Vogtle, Units 3 and 4, TS LCO 3.0.4 and SR 3.0.4. Existing LCO 3.0.4 exceptions are proposed to be deleted from various Vogtle, Units 3 and 4, TS LCOs consistent with TSTF-359, and the supporting documentation. The LAR proposes to add the LCO 3.0.4.c applicability note appropriately for the TS defining limits on parameters and values (i.e., LCO 3.4.10, RCS Specific Activity). The licensee has, consistent with the above analysis findings, added a note to the appropriate TS (i.e., TS 3.4.14) to state that the revised TS LCO 3.0.4.b, allowing mode changes with inoperable equipment, is not applicable for LTOP.

Limited Time in TS Required Actions Any temporary risk increase will be limited by, among other factors, duration constraints imposed by the TS completion times of the inoperable systems. The TS LCO 3.0.4.b allowance will be used only when the licensee determines that there is a high likelihood that the LCO will be satisfied following the mode change. This will minimize the likelihood of additional temporary risk increases associated with the need to exit a mode due to failure to restore the unavailable equipment within the CT. In most cases, licensees will enter into a higher mode with the intent to move up to Mode 1 (power operation).

As discussed in Section 3.2 (of this SE), the revised Reactor Oversight Process (ROP) monitors unplanned power changes as a performance indicator. The ROP, thus, discourages licensees from entering a mode or other specified condition in the applicability of an LCO, and moving up in power, when there is a likelihood that the mode would have to be subsequently exited due to failure to restore the unavailable equipment within the CT. Another disincentive for licensees to enter a higher mode when an LCO is not met is related to reporting requirements. 10 CFR 50.72 and 50.73 state that a report is required when a nuclear plant shutdown or mode change is required by TSs. The NRCs ROP will provide the framework for inspectors and other NRC staff to follow the history at a specific plant of entering higher modes while an LCO is not met and use such information in assessing the licensees actions and performance.

3.1.2 Risk Assessment and Risk Management of Mode Changes According to Section 2.4, Description of the Proposed Changes, of the application, TS LCO 3.0.4.b would allow mode changes provided that a plant risk assessment is conducted and risk management actions are implemented, if appropriate.

Section 3.0, Technical Evaluation, of the application states that SNC uses a fleet-wide process to implement the requirements of 10 CFR 50.65(a)(4), including the configuration risk management program (CRMP) model. The CRMP model is applied to assess plant configurations in Modes 1-3, consistent with the guidance in NUMARC 93-01, as endorsed by RG 1.160, Revision 4. For shutdown conditions, SNC performs risk assessments using a shutdown defense-in-depth model and software tool, which follow the principles of NUMARC 91-06, as referenced in NUMARC 93-01 and endorsed by RG 1.160, Revision 4.

With all required safety systems and components operable, a plant can transition up in operational condition to power operation. With one or more technical specification required system(s) or component(s) inoperable, the change to LCO 3.0.4 permits a plant to transition up in mode to power operation if the inoperable system(s) or component(s) are not in a pre-analyzed higher risk category. Prior to the mode transition, a 10 CFR 50.65(a)(4) based risk assessment is performed and the requisite risk management actions are taken. The proposed addition of LCO 3.0.4.b allows entry into a MODE or other specified condition in the Applicability with the LCO not met after performance of a risk assessment addressing inoperable systems and components, consideration of the results, determination of the acceptability of entering the MODE or other specified condition in the Applicability, and establishment of risk management actions, if appropriate. The proposed TS Bases for LCO 3.0.4.b describe that quantitative, qualitative, or blended approaches may be used to perform the risk assessment, utilizing plant programs, procedures, and criteria that are in place to implement the risk assessment required by 10 CFR 50.65(a)(4). This approach is consistent with the guidance in NUMARC 93-01, Section 11.3.2, General Guidance for the Assessment -

Power Operations and Shutdown. The proposed TS Bases also describe that the risk assessment, for the purposes of LCO 3.0.4.b, must take into account all inoperable TS equipment regardless of whether the equipment is included in the licensees normal 10 CFR 50.65(a)(4) risk assessment scope. The risk assessments will be conducted using the procedures and guidance endorsed by RG 1.160, Revision 4. The results of the risk assessment shall be considered in determining the acceptability of entering the MODE or other specified condition in the Applicability statement, and any corresponding risk management actions.

Under the proposed LCO 3.0.4.b, a risk assessment and establishment of risk management actions, as appropriate, are required for determination of acceptable risk for entering MODE or other specified conditions in the Applicability when an LCO is not met. Elements of acceptable risk assessment and risk management actions are included in Section 11 of NUMARC 93-01, Assessment of Risk Resulting from Performance of Maintenance Activities Revision 4F, April 2018 (ML18120A069), as endorsed by RG 1.160 Revision 4., which addresses general guidance for conduct of the risk assessment, gives quantitative and qualitative guidelines for establishing risk management actions, and provides example risk management actions. These risk management actions include actions to plan and conduct other activities in a manner that controls overall risk, actions to increase risk awareness by shift and management personnel, actions to reduce the duration of the conditions, actions to minimize the magnitude of risk increases (establishment of backup success paths or compensatory measures), and determination that the proposed Mode change is acceptable.

The thresholds of the cumulative (aggregate) risk impacts, assessed pursuant to 10 CFR 50.65(a)(4) and the associated implementation guidance, are based on the permanent change guidelines in NRC RG 1.174. When the plant is in a shutdown MODE, qualitative risk assessments are conducted using the shutdown defense-in-depth model, which is based upon NUMARC 91-06. Therefore, the licensee will manage the risk associated with exercising TS LCO 3.0.4 in conjunction with the risk from other concurrent plant activities. The NRC staff also finds that the licensee meets the 10 CFR 50.65(a)(4) shutdown risk assessment through the use of their defense-in-depth tool which follows NUMARC 91-06 as applied in NUMARC 93-01 risk assessment conducted using the procedures and guidance in RG 1.160, Revision 4. This risk assessment will be performed prior to transitioning up in mode, in shutdown, cumulative risk impacts account for unavailable equipment and plant conditions. If the assessment determines a KSF will have no available defense-in-depth (Red condition), voluntary entry into the configuration is not permitted and the mode change is not allowed. If the assessment determines the KSFs have at least one set of SSCs, including supports, (Orange or Yellow condition), then the mode change is allowed provided risk is managed with implementation of appropriate contingency actions. In this design, automated actuation of the passive systems as required by Technical Specifications during shutdown reduces risk compared to non-passive operating PWRs. In addition, station procedures contain guidance to avoid elevated risk when possible (Orange or Yellow condition) and to minimize time at reduced RCS inventory.

3.2 Oversight The ROP provides a means for assessing the licensees performance in the application of the proposed mode change flexibility. The adequacy of the licensees assessment and management of maintenance-related risk is addressed by existing inspection procedures and guidance for 10 CFR 50.65(a)(4). These inspection procedures and guidance address application of the licensees (a)(4) program to support risk-informed TSs.

Adoption of the proposed change will make failure to assess and manage the risk of an upward mode change with inoperable equipment covered by TSs, prior to commencing such a mode change, a violation of TSs. Further, as explained above in general, under most foreseeable circumstances, such a change in configuration would also require a risk assessment under 10 CFR 50.65(a)(4). Inoperable systems or components will necessitate maintenance to restore them to operability, and hence a 10 CFR 50.65(a)(4) risk assessment would be performed prior to the performance of those maintenance actions (except for immediate plant stabilization and restoration actions if necessary). Further, before altering the plants configuration, including plant configuration changes associated with mode changes, the licensee must update the existing (a)(4) risk assessment to reflect those changes.

The NRC staff endorsed the use of revision 4F to NUMARC 9301 in Regulatory Guide 1.160, Revision 4. In Regulatory Guide 1.160, Section 1.8 Scope of Initiators to be Considered for Shutdown Conditions, the NRC staff also endorses NUMARC 9106 section 4.0 Shutdown Safety Issues where it is applied in NUMARC 9301. As stated in the associated Vogtle, Units 3and 4, shutdown actions LAR (ML25023A275) Section 2.2 Current Requirements, the Vogtle, Units 3 and 4, UFSAR references the current revision of RG 1.160 (revision 4). This common Vogtle, Units 3 and 4, UFSAR licensing basis is applicable to the proposed Vogtle, Units 3 and 4, mode restraints LAR under review in this safety evaluation. Therefore, the licensees use of NUMARC 93-01 and NUMARC 91-06 for implementation of 10 CFR 50.65 section (a)(4) is based on endorsed NRC staff guidance. Future changes to the Vogtle, Units 3 and 4, licensing basis regarding compliance with 10 CFR 50.65(a)(4), will require the application of the considerations included in 10 CFR 50.59 to determine if prior NRC approval must be obtained before making the change. In addition, continued compliance with the requirements of 10 CFR 50.65(a)(4) are inspected under the ROP and the Significance Determination Process. Therefore, the NRC staff finds that the requirements of 10 CFR 50.59, in conjunction with the Vogtle, Units 3 and 4, licensing basis, and the ROP provide the appropriate level of regulatory control to support a finding of reasonable assurance that the endorsed methodology will be reliably implemented.

3.3 Evaluation of Proposed Technical Specification Changes The LAR proposes to remove the Actions Notes stating LCO 3.0.4 is not applicable from:

(1) LCO 3.3.17, Post Accident Monitoring (PAM) Instrumentation, (2) LCO 3.3.18, Remote Shutdown Workstation (RSW), and (3) LCO 3.4.9, RCS Leakage Detection Instrumentation.

These notes allow SNC to enter MODES or other conditions in the Applicability with these LCO not met provided they meet the required actions specified for each LCO that is not met. The effect of deleting this note in combination with the proposed changes to LCO 3.0.4 is to require SNC to determine if the risk is acceptable and to implement appropriate risk management actions in accordance with LCO 3.0.4.b prior to entering the MODE or other condition specified in the applicability. In addition, SNC would still be required to comply with the required actions for the LCO that are not met. The NRC staff finds that these changes are more conservative than the current specifications, and are, therefore, acceptable.

The LAR also proposes to add a note to LCO 3.4.14, Low Temperature Overpressure Protection (LTOP) stating LCO 3.0.4.b is not applicable. This note would prevent the new changes to LCO 3.0.4 from being applied to the LTOP system. The net effect of this change in combination with the other changes in the LAR is to maintain the current TS requirements since the new features of the LCO 3.0.4 changes would not be applicable to LTOP. Based on this, the NRC staff finds the change to be acceptable.

The NRC staff reviewed the proposed TS changes against the requirements of 10 CFR 50.36.

Based on the evaluation in Sections 3.1 and 3.2 above, the staff concludes that the proposed changes to LCOs 3.0.4, 3.3.17, 3.3.18, 3.4.9, 3.4.10 and 3.4.14 are acceptable because the LCOs will continue to ensure the lowest functional capability or performance levels of equipment required for safe operation of the facility are maintained. The requirements of 10 CFR 50.36(c)(2)(i) will, therefore, continue to be met. In addition, the change to SR 3.0.4 is also acceptable as the Vogtle, Units 3 and 4, surveillance requirements will continue to ensure that the necessary quality of systems and components is maintained, that facility operation will be within safety limits, and that the limiting conditions for operation will be met. Therefore, the requirements of 10 CFR 50.36(c)(3) will continue to be met.

4.0 STATE CONSULTATION

In accordance with the Commissions regulations, the Georgia State official was notified of the proposed issuance of the amendments on December 4, 2025. The State official had no comments on December 4, 2025.

5.0 ENVIRONMENTAL CONSIDERATION

The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and changes surveillance requirements. The NRC staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendments involve no significant hazards consideration, and there has been no public comment on such finding published in the Federal Register on February 18, 2025 (90 FR 9743).

Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.

6.0 CONCLUSION

The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) there is reasonable assurance that such activities will be conducted in compliance with the Commissions regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

Principal Contributors: R. Elliott, NRR M. Pohida, NRR M. Swim, NRR K. Tetter, NRR J. Hughey, NRR Date: December 30, 2025

ML25351A015 NRR-058 OFFICE NRR/DORL/LPL2-1/PM NRR/DORL/LPL2-1/LA NRR/DSS/STSB/BC NAME JLamb KZeleznock SMehta DATE 12/16/2025 12/17/2025 12/23/2025 OFFICE NRR/DSS/SNSB/BC NRR/DRA/APLC/BC NRR/DRA/APOB/BC NAME NDifrancesco (RBeaton for)

SAlferink (MPohida for)

APatz DATE 12/18/2025 12/18/2025 12/19/2025 OFFICE NRR/DORL/LPL2-1/BC NRR/DORL/LPL2-1/PM NAME MMarkley (SWilliams for)

JLamb DATE 12/30/2025 12/30/2025