NL-25-0378, Core Operating Limits Report, Cycle 2

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Core Operating Limits Report, Cycle 2
ML25287A158
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Site: Vogtle Southern Nuclear icon.png
Issue date: 10/14/2025
From: Joyce R
Southern Nuclear Operating Co
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Office of Nuclear Reactor Regulation, Document Control Desk
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NL-25-0378
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Text

Southern Nuclear Operating Company, Inc.

3535 Colonnade Parkway Birmingham, AL 35243 October 14, 2025 Docket No.: 52-026 NL 0378 10 CFR 52.97(c)

U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Southern Nuclear Operating Company Vogtle Electric Generating Plant - Unit 4 Core Operating Limits Report, Cycle 2 Ladies and Gentlemen:

In accordance with Technical Specifications (TS) 5.6.3.d for Vogtle Electric Generating Plant (VEGP) Unit 4, Southern Nuclear Operating Company (SNC) submits the VEGP Core Operating Limits Report (COLR) for Unit 4, Cycle 2. provides the Non-Proprietary version of the COLR. provides the Proprietary version of the COLR. The enclosure contains Proprietary information; therefore, SNC requests that this enclosure be withheld under the provisions of 10 CFR 2.390. is the Westinghouse application for withholding proprietary information from public disclosure and accompanying affidavit. Enclosure 2 contains information proprietary to Westinghouse Electric Company LLC (Westinghouse); it is supported by an Affidavit signed by Westinghouse, the owner of information. The Affidavit sets forth the basis on which the information may be withheld from public disclosure by the Nuclear Regulatory Commission (Commission) and addresses with specificity the considerations listed in paragraph (b)(4) of Section 2.390 of the Commissions regulations.

Accordingly, it is respectfully requested that the information that is proprietary to Westinghouse be withheld from public disclosure in accordance with 10 CFR Section 2.390 of the Commissions regulations.

Correspondence with respect to the copyright or proprietary aspects of the items listed above or the supporting Westinghouse Affidavit should reference CAW-25-042 and should be addressed WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390 (DECONTROLLED UPON REMOVAL OF ENCLOSURE 2)

~ Southern Nuclear

U.S. Nuclear Regulatory Commission NL 0378 Page 2 of 2 This letter contains no regulatory commitments. This letter has been reviewed and determined not to contain security-related information.

If you have any questions, please contact me at 205.992.6468.

Respectfully submitted, Ryan M. Joyce Licensing Manager Southern Nuclear Operating Company

Enclosures:

1) Vogtle Electric Generating Plant (VEGP) Unit 4 - Core Operating Limits Report (COLR), Cycle 2 (Non-Proprietary)
2) Vogtle Electric Generating Plant (VEGP) Unit 4 - Core Operating Limits Report (COLR), Cycle 2 (Proprietary) (Withheld Information)
3) Vogtle Electric Generating Plant (VEGP) Unit 4 - Westinghouse Application for Withholding Proprietary Information from Public Disclosure CAW-25-042 and accompanying Affidavit cc:

Regional Administrator, Region II Project Manager - VEGP 3&4 Senior Resident Inspector - VEGP 3&4 Document Services RTYPE: VNP.LI.L00 RMJOYCE Digitally signed by RMJOYCE DN: cn=RMJOYCE ou=Employee e=RMJOYCE@southernco.com Reason: I am approving this document Location:

Date: 2025-10-14 07:22-05:00

Southern Nuclear Operating Company NL 0378 Vogtle Electric Generating Plant (VEGP) Unit 4 Core Operating Limits Report (COLR), Cycle 2 (Non-Proprietary)

(This Enclosure consists of 35 pages, including this cover page)

Westinghouse Non-Proprietary Class 3 Information included in this material is proprietary and cannot be disclosed or used for any reason beyond the intended purpose without the prior written consent of Westinghouse Electric Company LLC.

This document may contain technical data subject to the export control laws of the United States. In the event that this document does contain such information, the Recipients acceptance of this document constitutes agreement that this information in document form (or any other medium), including any attachments and exhibits hereto, shall not be exported, released or disclosed to foreign persons whether in the United States or abroad by recipient except in compliance with all U.S. export control regulations. Recipient shall include this notice with any reproduced or excerpted portion of this document or any document derived from, based on, incorporating, using or relying on the information contained in this document.

2025 Westinghouse Electric Company LLC All Rights Reserved Page A-1 of 34 Core Operating Limits Report (COLR) for the Vogtle Electric Generating Plant, Unit 4 Cycle 2 August 2025 Authored by:

Luke G. Shuler Nuclear Design A Chandler E. Walker Nuclear Design A Verified by*:

Blaine W. Taylor Nuclear Design A

  • Three-pass verification (3PV) was used to verify this document.

Approved by:

Zebulon E. Plotnick Nuclear Design A

Attachment:

34 pages Electronically Approved Records are Authenticated in the Electronic Document Management System

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

@Westinghouse

Westinghouse Non-Proprietary Class 3 Page A-2 of 34 VOGTLE ELECTRIC GENERATING PLANT (VEGP)

UNIT 4 CYCLE 2 CORE OPERATING LIMITS REPORT (COLR)

Version 1 August 2025

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-3 of 34 1.0 CORE OPERATING LIMITS REPORT This Core Operating Limits Report (COLR) for the Vogtle Electric Generating Plant, Unit 4, Cycle 2 has been prepared in accordance with the requirements of Technical Specification 5.6.3.

The Technical Specification Safety Limits (SLs) and Limiting Conditions for Operation (LCOs) affected by this report are listed below:

SL 2.1.1 Reactor Core SLs LCO 3.1.1 SHUTDOWN MARGIN (SDM)

LCO 3.1.3 Moderator Temperature Coefficient (MTC)

LCO 3.1.5 Shutdown Bank Insertion Limits LCO 3.1.6 Control Bank Insertion Limits LCO 3.2.1 Heat Flux Hot Channel Factor (FQ(Z)) (Constant Axial Offset Control (CAOC) W(Z) Methodology)

LCO 3.2.2 Nuclear Enthalpy Rise Hot Channel Factor (F¨+

N )

LCO 3.2.3 AXIAL FLUX DIFFERENCE (AFD) (Constant Axial Offset Control (CAOC) Methodology)

LCO 3.2.5 On-Line Power Distribution Monitoring System (OPDMS)-Monitored Parameters LCO 3.4.1 RCS Pressure, Temperature, and Flow Departure from Nucleate Boiling (DNB) Limits LCO 3.9.1 Boron Concentration

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-4 of 34 2.0 OPERATING LIMITS 2.1 Reactor Core SLs (SL 2.1.1)

The Reactor Core SLs for MODES 1 and 2 are:

2.1.1 The combination of THERMAL POWER, RCS highest loop cold leg temperature, and pressurizer pressure shall not exceed the limits specified in Table 2.1.1 and Figure 2.1.1.

2.2 SHUTDOWN MARGIN (SDM)

(LCO 3.1.1)

The SDM limit for MODE 2 with keff < 1.0 is:

2.2.1 7KH6'0VKDOOEHJUHDWHUWKDQRUHTXDOWRNN.

The SDM limit for MODES 3, 4, and 5 is:

2.2.2 7KH6'0VKDOOEHJUHDWHUWKDQRUHTXDOWRNN.

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-5 of 34 Table 2.1.1 Reactor Core Safety Limits a,c

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-6 of 34 Figure 2.1.1 Reactor Core Safety Limits a,c

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-7 of 34 2.3 Moderator Temperature Coefficient (MTC)

(LCO 3.1.3) 7KH%2/$5207&XSSHUOLPLW(SR 3.1.3.1) for MODE 1 and MODE 2 with keff 1.0 is:

2.3.1 The MTC shall be more negative than or equal to the power-dependent upper limit specified in Figure 2.3.1.

7KH(2/$5207&ORZHUOLPLW(SR 3.1.3.2) for MODES 1, 2, and 3 is:

2.3.2 The MTC shall be less negative than or equal to

[

]a,c 7KH$52+)307&VXUYHLOODQFHOLPLWV(SR 3.1.3.2) for EOL are:

2.3.3 At 300 ppm, the MTC shall be less negative than or equal to

[

]a,c 2.3.4 At 60 ppm, the MTC shall be less negative than or equal to

[

]a,c SR 3.1.3.2 does not need to be performed provided both of the following conditions are met:

2.3.5 The measured-to-predicted differences for the parameters listed in Table 2.3.5 are within their specified criteria.

2.3.6 The value of the revised predicted MTC, calculated in accordance with Table 2.3.6, is less negative WKDQWKH$52+)307&VXUYHLOODQFHOLPLWDW

300 ppm.

Note: ARO stands for All Rods Out BOL stands for Beginning of (Cycle) Life EOL stands for End of (Cycle) Life HFP stands for Hot Full (Thermal) Power

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-8 of 34 Figure 2.3.1 BOL/ARO MTC Upper Limit a,c

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)
      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Table 2.3.5 Benchmark Criteria for Application of the EOL MTC Measurement Conditional Exemption Parameter Criteria Time/Activity Power Ascension Testing Assembly Power +/- 0.1 0 or 10%

Routinely at RTP

[

] a,c lncore Quadrant

+/-4%

Power Ascension Tilt (Low Power)

Testing Power Ascension lncore Quadrant Testing Tilt (RTP)

+/-2%

Routinely at RTP

[

] a,c Low Power Physics Testing Power Ascension Core Reactivity

+/- 1000 pcm Testing Routine Surveillance Requirement Low Power Physics SOL HZP ITC

+/- 2.0 pcm/°F Testing Individual

+/- 75 pcm Low Power Physics Bank Worth or 10%

Testing Total

+/-5.6%

Low Power Physics Bank Worth Testing Note: EFPD stands for effective full power days EQXE stands for equilibrium xenon HZP stands for Hot Zero (Thermal) Power Minimum Documentation Frequency Twice - At an intermediate power (40-75% RTP) plateau and at a full power (> 90% RTP) plateau Every 31 EFPDs after reaching RTP Once - At a low power (~ 30% RTP) plateau Once - At the RTP power ascension test plateau Every 31 EFPDs after reaching RTP Once - After fuel load and prior to MODE 1 (SR 3.1.2.1)

Once - In MODE 1 upon reaching RTP and EQXE conditions

("Hot Full Power Boron Endpoint")

After 60 EFPD, every 31 EFPD thereafter (continuation of SR 3.1.2.1)

Once - After fuel load and prior to MODE 1 (needed to support SR 3.1.3.1 )

Once - After fuel load and prior to MODE 1 Once - After fuel load and prior to MODE 1 ITC stands for Isothermal Temperature Coefficient OPDMS stands for Online Power Distribution Monitoring System RTP stands for rated thermal power SR stands for surveillance requirement Page A-9 of 34

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-10 of 34 Table 2.3.6 Algorithm for Calculation of the Revised Predicted MTC at 300 ppm a,c

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-11 of 34 2.4 Shutdown Bank Insertion Limits (LCO 3.1.5)

The shutdown bank insertion limits in MODES 1 and 2 are:

2.4.1 All shutdown banks shall be positioned greater than or equal to [

]a,c steps withdrawn (swd).

2.5 Control Bank Insertion Limits (LCO 3.1.6)

The control bank rod insertion limits (RILs), sequence limits, and overlap limits in MODE 1 and MODE 2 with keff 1.0 are:

2.5.1 M-Bank Limits 2.5.1.a With the OPDMS functional, the M-Banks shall be positioned greater than or equal to the power-dependent limit specified in Figure 2.5.1.a.

2.5.1.b With the OPDMS not functional, the M-Banks shall be positioned greater than or equal to the power-dependent limit specified in Figure 2.5.1.b. M-Bank Insertion Limits are provided for two CAOC Operating Spaces (COSs). The M-Bank Insertion Limits for each COS shall be used in conjunction with the associated Axial Flux Difference Limits for the COS.

(Note: The same RILs apply regardless of OPDMS functionality or COS for this cycle.)

2.5.1.c The M-Banks shall be considered fully withdrawn from the core when positioned greater than or equal to [

]a,c swd.

Note: ARO positions of [

]a,c through [

]a,c swd may be utilized during rod repositioning without affecting the core safety analysis.

2.5.1.d When the ARO position is [

]a,c swd, the M-Banks shall be operated in sequence as specified in Table 2.5.1.d, and each M-Bank not fully withdrawn from the core shall be operated within the overlap limits specified in Table 2.5.1.d.

2.5.1.e When the ARO position is [

]a,c swd, the M-Banks shall be operated in sequence as specified in Table 2.5.1.e, and each M-Bank not fully withdrawn from the core shall be operated within the overlap limits specified in Table 2.5.1.e.

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-12 of 34 2.5.1.f When the ARO position is [

]a,c swd, the M-Banks shall be operated in sequence as specified in Table 2.5.1.f, and each M-Bank not fully withdrawn from the core shall be operated within the overlap limits specified in Table 2.5.1.f.

2.5.1.g When the ARO position is [

]a,c swd, the M-Banks shall be operated in sequence as specified in Table 2.5.1.g, and each M-Bank not fully withdrawn from the core shall be operated within the overlap limits specified in Table 2.5.1.g.

2.5.2 Bank AO Limits 2.5.2.a Bank AO shall be positioned greater than or equal to the power-dependent limit specified in Figure 2.5.2.a.

2.5.2.b Bank AO shall be considered fully withdrawn from the core when positioned greater than or equal to [

]a,c swd.

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-13 of 34 Figure 2.5.1.a M-Bank Rod Insertion Limits (OPDMS Functional) a,c

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-14 of 34 Figure 2.5.1.b M-Bank Rod Insertion Limits for CAOC Operating Spaces 1 and 2 (OPDMS Not Functional) a,c

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)
      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Table 2.5.1.d M-Bank Sequences and Overlap Settings

[

]a,c steps ARO

'--------=

a,c Page A-15 of 34

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Table 2.5.1.e M-Bank Sequences and Overlap Settings

[

]a,c steps ARO a,c Table 2.5.1.f M-Bank Sequences and Overlap Settings

[

]a,c steps ARO a,c Page A-1 6 of 34

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Table 2.5.1.g M-Bank Sequences and Overlap Settings

[

]a,c steps ARO a,c Page A-1 7 of 34

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-18 of 34 Figure 2.5.2.a Bank AO Rod Insertion Limits a,c

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-19 of 34 2.6 Heat Flux Hot Channel Factor (FQ(Z)) (Constant Axial Offset Control (CAOC) W(Z)

Methodology)

(LCO 3.2.1)

The FQ(Z) limits in MODE 1 with THERMAL POWER 25% RTP and with the OPDMS not functional with respect to LCO 3.2.5 a, b, and c are:

2.6.1 FQ C(Z) 

CFQ P for P > 0.5 FQ C(Z) 

CFQ 0.5 for P 0.5 where: P =

THERMAL POWER RATED THERMAL POWER CFQ = 2.60 2.6.2 FQ C(Z) = FQ M(Z) FQ MU(Z) where: FQ M(Z) represents the measured value of FQ(Z), and is obtained from power distribution measurement results.

FQ MU(Z) is a factor that accounts for fuel manufacturing tolerances (net effect being a factor of 1.03) and power distribution measurement uncertainty, the latter being dependent on the fraction of inoperable incore detectors and the detector measurement variability at the conditions of the power distribution measurement. Therefore, FQ MU(Z) is defined at the time of measurement using approved methods.

2.6.3 FQ W(Z) 

CFQ P for P > 0.5 FQ W(Z) 

CFQ 0.5 for P 0.5 where: FQ W(Z) = FQ C(Z) *

[W(Z)]COLR P

  • AQ(Z)
  • Rj for P > 0.5 FQ W(Z) = FQ C(Z) *

[W(Z)]COLR 0.5

  • AQ(Z)
  • Rj for P 0.5 The calculation of FQW(Z) in the equations above is dependent on the applicable CAOC operating space, as detailed in items 2.6.3.a and 2.6.3.c below. Margin to the FQW(Z) limit may be improved by implementing a more restrictive COS in accordance with TS LCO 3.2.1 Required Action B.1.1. If this margin improvement is not sufficient to restore FQW(Z) to within its limits, the THERMAL POWER limits discussed in Item 2.6.3.d below may be required in accordance with TS LCO 3.2.1 Required Action B.2.1.
      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-20 of 34 2.6.3.a [W(Z)]COLR is a cycle-dependent function that accounts for power distribution transients encountered during normal operation. The [W(Z)]COLR function is dependent on CAOC operating space, core elevation and core burnup.

[W(Z)]COLR values are specified in Tables 2.6.3.a.1 and 2.6.3.a.2 for COS1 and COS2, respectively.

2.6.3.b The AQ(Z) factor adjusts the surveillance to the Target AO conditions. AQ(Z) can be assumed to be equal to 1.0 if the conditions discussed below are met, or may be determined for specific surveillance conditions using approved methods. Specifically, AQ(Z) can be assumed to be equal to 1.0 if the surveillance is performed at core conditions consistent with updating the measured Target AO and Control Bank M1 is not inserted below [

]a,c steps withdrawn. Alternatively, AQ(Z) can be assumed to be equal 1.0 if a surveillance specific W(Z) function is being used that is consistent with the core conditions of the surveillance.

2.6.3.c The Rj penalty factors account for the potential decrease in transient FQ margin between surveillances. The Rj factors for COS1 and COS2 are provided in Tables 2.6.3.c.1 and 2.6.3.c.2, respectively.

2.6.3.d Table 2.6.3.d provides the required limits on thermal power for each COS in the event that additional margin is required.

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)
      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Table 2.6.3.a.1

[W(Z)]C0 LR Function for COS1 Core

[W(Z)]coLR Factors by Core Burnup Elevation (in) 150 6000 12000 18000 0.00 1.345 1.388 1.418 1.454 2.01 1.343 1.388 1.415 1.455 4.02 1.331 1.366 1.404 1.446 6.04 1.324 1.350 1.391 1.438 8.05 1.315 1.354 1.373 1.417 10.06 1.306 1.341 1.363 1.405 12.07 1.295 1.322 1.346 1.382 14.08 1.256 1.307 1.337 1.371 16.10 1.243 1.287 1.318 1.350 18.11 1.236 1.275 1.304 1.337 20.12 1.227 1.261 1.287 1.318 22.13 1.216 1.246 1.268 1.302 24.14 1.203 1.229 1.248 1.289 26.16 1.190 1.214 1.229 1.273 28.17 1.179 1.198 1.210 1.252 30.18 1.162 1.184 1.193 1.229 32.19 1.153 1.170 1.181 1.213 34.20 1.144 1.156 1.166 1.192 36.22 1.134 1.144 1.147 1.173 38.23 1.125 1.133 1.134 1.156 40.24 1.1 17 1.122 1.120 1.143 42.25 1.1 16 1.110 1.106 1.132 44.26 1.123 1.102 1.098 1.123 46.28 1.131 1.099 1.097 1.118 48.29 1.141 1.102 1.103 1.139 50.30 1.158 1.107 1.110 1.160 52.31 1.176 1.112 1.119 1.184 54.32 1.195 1.114 1.129 1.209 56.34 1.212 1.128 1.138 1.235 58.35 1.229 1.138 1.149 1.259 60.36 1.244 1.149 1.162 1.282 62.37 1.257 1.161 1.172 1.304 64.38 1.269 1.171 1.190 1.324 66.40 1.280 1.179 1.209 1.346 68.41 1.289 1.186 1.226 1.366 Page A-21 of 34

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Table 2.6.3.a.1

[W(Z)]coLR Function for COS1 Core

[W(Z)]coLR Factors by Core Burnup Elevation (in) 150 6000 12000 18000 70.42 1.296 1.192 1.242 1.383 72.43 1.302 1.196 1.259 1.395 74.44 1.305 1.188 1.269 1.388 76.46 1.308 1.200 1.287 1.414 78.47 1.310 1.202 1.299 1.427 80.48 1.310 1.202 1.310 1.433 82.49 1.309 1.202 1.320 1.435 84.50 1.306 1.201 1.328 1.428 86.52 1.303 1.202 1.340 1.442 88.53 1.303 1.202 1.347 1.441 90.54 1.300 1.201 1.349 1.435 92.55 1.296 1.201 1.353 1.433 94.56 1.293 1.205 1.345 1.397 96.58 1.289 1.202 1.353 1.421 98.59 1.286 1.203 1.350 1.422 100.60 1.282 1.205 1.346 1.415 102.61 1.274 1.205 1.337 1.402 104.62 1.267 1.205 1.329 1.384 106.64 1.255 1.200 1.316 1.371 108.65 1.244 1.195 1.304 1.358 110.66 1.231 1.188 1.288 1.342 112.67 1.218 1.182 1.273 1.325 114.68 1.206 1.185 1.260 1.302 116.70 1.186 1.178 1.238 1.278 118.71 1.174 1.177 1.237 1.275 120.72 1.161 1.177 1.229 1.277 122.73 1.159 1.175 1.216 1.278 124.74 1.163 1.174 1.219 1.277 126.76 1.159 1.175 1.214 1.270 128.77 1.157 1.173 1.208 1.266 130.78 1.154 1.175 1.203 1.257 132.79 1.152 1.185 1.200 1.247 134.80 1.159 1.194 1.219 1.248 136.82 1.168 1.199 1.236 1.254 138.83 1.175 1.209 1.241 1.250 140.84 1.191 1.228 1.256 1.259 142.85 1.218 1.239 1.269 1.270 144.86 1.241 1.258 1.287 1.289 Page A-22 of 34

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Table 2.6.3.a.1

[W(Z)]coLR Function for COS1 Core

[W(Z)]coLR Factors by Core Burnup Elevation (in) 150 6000 12000 18000 146.88 1.263 1.276 1.309 1.305 148.89 1.286 1.292 1.325 1.323 150.90 1.308 1.306 1.339 1.352 152.91 1.335 1.325 1.364 1.368 154.92 1.357 1.342 1.396 1.392 156.94 1.382 1.397 1.477 1.464 158.95 1.396 1.444 1.550 1.570 160.96 1.419 1.465 1.573 1.587 162.97 1.477 1.517 1.637 1.646 164.98 1.500 1.538 1.665 1.675 167.00 1.517 1.545 1.665 1.663 169.01 1.530 1.557 1.684 1.688 Notes:

The [W(Z)]C0 LR values are unit-less and the core burnup values are in units of MWD/MTU.

. [

The top and bottom 8% of the core (inclusive) are excluded from the F~ (Z) evaluation because of the difficulty of making a precise measurement in these regions and because of the low probability that these regions would be more limiting than the safety analyses.

Page A-23 of 34

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Table 2.6.3.a.2

[W(Z)]coLR Function for COS2 Core

[W(Z)]coLR Factors by Core Burnup Elevation (in) 150 6000 12000 18000 0.00 1.307 1.340 1.370 1.404 2.01 1.305 1.340 1.367 1.405 4.02 1.292 1.322 1.357 1.398 6.04 1.285 1.306 1.345 1.390 8.05 1.279 1.310 1.328 1.369 10.06 1.271 1.299 1.320 1.359 12.07 1.259 1.280 1.303 1.339 14.08 1.225 1.267 1.296 1.329 16.10 1.213 1.248 1.279 1.310 18.11 1.206 1.237 1.266 1.297 20.12 1.197 1.224 1.250 1.280 22.13 1.186 1.21 1 1.232 1.264 24.14 1.173 1.195 1.213 1.253 26.16 1.160 1.181 1.195 1.237 28.17 1.149 1.165 1.177 1.218 30.18 1.133 1.151 1.161 1.197 32.19 1.122 1.137 1.149 1.182 34.20 1.1 14 1.126 1.134 1.162 36.22 1.106 1.115 1.115 1.144 38.23 1.098 1.104 1.100 1.128 40.24 1.090 1.094 1.088 1.111 42.25 1.089 1.083 1.078 1.097 44.26 1.097 1.077 1.071 1.086 46.28 1.105 1.075 1.071 1.092 48.29 1.1 16 1.078 1.079 1.113 50.30 1.135 1.084 1.086 1.135 52.31 1.153 1.089 1.095 1.159 54.32 1.172 1.091 1.106 1.185 56.34 1.190 1.106 1.116 1.212 58.35 1.207 1.118 1.128 1.237 60.36 1.223 1.129 1.141 1.261 62.37 1.237 1.141 1.153 1.282 64.38 1.251 1.152 1.174 1.304 66.40 1.263 1.161 1.194 1.327 68.41 1.272 1.169 1.213 1.348 70.42 1.281 1.176 1.232 1.366 72.43 1.288 1.181 1.250 1.380 74.44 1.292 1.174 1.262 1.375 Page A-24 of 34

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Table 2.6.3.a.2

[W(Z)]coLR Function for COS2 Core

[W(Z)]coLR Factors by Core Burnup Elevation (in) 150 6000 12000 18000 76.46 1.296 1.188 1.281 1.403 78.47 1.300 1.191 1.294 1.418 80.48 1.301 1.192 1.307 1.427 82.49 1.301 1.193 1.318 1.431 84.50 1.300 1.195 1.327 1.426 86.52 1.299 1.198 1.340 1.440 88.53 1.300 1.200 1.347 1.441 90.54 1.298 1.201 1.349 1.435 92.55 1.296 1.201 1.352 1.433 94.56 1.293 1.205 1.343 1.394 96.58 1.288 1.200 1.348 1.416 98.59 1.284 1.199 1.343 1.416 100.60 1.278 1.197 1.337 1.407 102.61 1.269 1.191 1.326 1.391 104.62 1.260 1.188 1.315 1.371 106.64 1.247 1.180 1.299 1.355 108.65 1.234 1.171 1.284 1.340 110.66 1.218 1.167 1.265 1.318 112.67 1.201 1.162 1.249 1.297 114.68 1.187 1.159 1.238 1.271 116.70 1.164 1.158 1.217 1.253 118.71 1.149 1.157 1.211 1.255 120.72 1.134 1.155 1.200 1.255 122.73 1.133 1.150 1.193 1.253 124.74 1.135 1.145 1.193 1.250 126.76 1.131 1.142 1.186 1.240 128.77 1.126 1.138 1.177 1.233 130.78 1.120 1.142 1.168 1.220 132.79 1.1 17 1.149 1.170 1.209 134.80 1.121 1.155 1.187 1.210 136.82 1.129 1.157 1.200 1.212 138.83 1.139 1.168 1.203 1.212 140.84 1.153 1.186 1.217 1.222 142.85 1.179 1.200 1.230 1.229 144.86 1.204 1.215 1.247 1.243 146.88 1.223 1.231 1.265 1.253 148.89 1.242 1.248 1.276 1.270 150.90 1.260 1.266 1.285 1.301 Page A-25 of 34

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Table 2.6.3.a.2

[W(Z)]coLR Function for COS2 Core

[W(Z)]coLR Factors by Core Burnup Elevation (in) 150 6000 12000 18000 152.91 1.282 1.291 1.307 1.328 154.92 1.302 1.319 1.338 1.361 156.94 1.327 1.397 1.416 1.434 158.95 1.339 1.444 1.485 1.553 160.96 1.348 1.465 1.506 1.570 162.97 1.365 1.517 1.564 1.631 164.98 1.381 1.538 1.590 1.659 167.00 1.393 1.545 1.588 1.643 169.01 1.402 1.557 1.606 1.670 Notes:

The [W(Z)]C0 LR values are unit-less and the core burnup values are in units of MWD/MTU.

. [

The top and bottom 8% of the core (inclusive) are excluded from the F~ (Z) evaluation because of the difficulty of making a precise measurement in these regions and because of the low probability that these regions would be more limiting than the safety analyses.

Page A-26 of 34

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Table 2.6.3.c.1 Ri Margin Decrease Factors for COS1 Cycle Burnup Ri Cycle Burnup Ri Cycle Burnup Ri (MWD/MTU)

(MWD/MTU)

(MWD/MTU)

BU s 739.7 1.00 9192.0 1.04 16464.9 1.02 936.3 1.03 9388.5 1.03 16661.5 1.03 1132.8 1.04 9585.1 1.02 16858.0 1.03 1329.4 1.05 9781.7 1.02 17054.6 1.02 1526.0 1.02 9978.2 1.02 17447.7 1.02 1919.1 1.02 10174.8 1.03 17644.3 1.03 2115.6 1.01 12337.0 1.03 17840.8 1.03 3098.5 1.01 12533.6 1.02 18037.4 1.02 3295.0 1.00 12926.7 1.02 19413.4 1.02 6046.9 1.00 13123.3 1.03 19609.9 1.03 6243.5 1.01 15088.9 1.03 19806.5 1.03 7619.5 1.01 15285.5 1.02 20003.1 1.02 7816.0 1.02 15482.1 1.02 20985.9 1.02 8012.6 1.03 15678.6 1.03 21182.4 1.01 8209.2 1.03 16071.8 1.03 21772.1 1.01 8405.7 1.04 16268.3 1.02 BU.:: 21968.7 1.00 Notes:

Values may be interpolated to the surveillance cycle burnup.

Page A-27 of 34

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Table 2.6.3.c.2 Ri Margin Decrease Factors for COS2 Cycle Burnup Ri Cycle Burnup Ri Cycle Burnup Ri (MWD/MTU)

(MWD/MTU)

(MWD/MTU)

BU s 543.1 1.00 8209.2 1.04 15285.5 1.02 739.7 1.01 8405.7 1.04 15482.1 1.03 936.3 1.04 8602.3 1.05 16071.8 1.03 1132.8 1.05 8798.9 1.05 16268.3 1.02 1329.4 1.06 8995.4 1.04 17447.7 1.02 1526.0 1.03 9388.5 1.04 17644.3 1.03 1722.5 1.02 9585.1 1.03 18037.4 1.03 1919.1 1.02 9781.7 1.03 18234.0 1.02 2115.6 1.01 9978.2 1.02 19413.4 1.02 3098.5 1.01 10764.5 1.02 19609.9 1.03 3295.0 1.00 10961.1 1.03 20003.1 1.03 5064.1 1.00 12337.0 1.03 20199.6 1.02 5260.7 1.01 12533.6 1.02 20985.9 1.02 7422.9 1.01 12926.7 1.02 21182.4 1.01 7619.5 1.02 13123.3 1.03 21772.1 1.01 7816.0 1.02 14695.8 1.03 BU.:: 21968.7 1.00 8012.6 1.03 14892.4 1.02 Notes:

Values may be interpolated to the surveillance cycle burnup.

Page A-28 of 34

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Table 2.6.3.d Required THERMAL POWER Limits CAOC Operating Space Required Fow(Z) Margin Required THERMAL Improvement (%)

POWER Limit (%RTP) s 5.0 s 95 COS1

> 5.0

< 50 s 5.0 s 95 COS2

> 5.0

< 50 Page A-29 of 34

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-30 of 34 2.7 Nuclear Enthalpy Rise Hot Channel Factor (F¨+

N )

(LCO 3.2.2)

The F¨+

N limits in MODE 1 with THERMAL POWER 25% RTP and with the OPDMS not functional with respect to LCO 3.2.5 a, b, and c are:

2.7.1 F¨+

N = F¨+

RTP

  • 1 + PF¨+ * (1 P) where: P =

THERMAL POWER RATED THERMAL POWER F¨+

RTP = 1.72 PF¨+ = 0.3 2.8 AXIAL FLUX DIFFERENCE (AFD) (Constant Axial Offset Control (CAOC)

Methodology)

(LCO 3.2.3)

The AFD limits in MODE 1 with THERMAL POWER > 15% RTP and with the OPDMS not functional with respect to LCO 3.2.5 a, b, and c are:

2.8.1 The AFD shall be maintained within the target band about the target flux difference. The AFD target bands for COS1 and COS2 are provided in Table 2.8.1.

2.8.2 The AFD may deviate outside the target band with THERMAL POWER < 90%

RTP but 50% RTP, provided AFD is within the acceptable operation limits specified in Figure 2.8.2.

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-31 of 34 Table 2.8.1 CAOC Axial Flux Difference Operating Bands a,c

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

 

  

!B!

$B$#B!!$B!B'$B%$BB ) BB

42@=.B B

A4*6B6@AB411.=.9-.B

--.<?*,7.B<.=*?5:9B484?>B

+3/B B;0BB DF

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-33 of 34 2.9 On-Line Power Distribution Monitoring System (OPDMS)-Monitored Parameters (LCO 3.2.5) 2.9.1 The Peak Linear Heat Rate (PLHR) shall not exceed [

]a,c, as confirmed by Minimum Power Margin (MPM) > 0.0%, in MODE 1 with THERMAL POWER 25% RTP and with the OPDMS functional.

Note: The PLHR limit presented here is based on the hot fuel height.

2.9.2 The Nuclear Enthalpy Rise Hot Channel Factor (F¨+

N ) shall not exceed its limits, as confirmed by MPM > 0.0%, in MODE 1 with THERMAL POWER 25% RTP and with the OPDMS functional. The F¨+

N limits are:

F¨+

N = F¨+

RTP

  • 1 + PF¨+ * (1 P) where: P =

THERMAL POWER RATED THERMAL POWER F¨+

RTP = 1.72 PF¨+ = 0.3 2.9.3 The Departure from Nucleate Boiling Ratio (DNBR) shall be maintained greater than or equal to [

]a,c, as confirmed by MPM > 0.0%, in MODE 1 with THERMAL POWER 25% RTP and with the OPDMS functional.

2.9.4 The SHUTDOWN MARGIN (SDM) shall be greater than or equal 1.6% NNDV

confirmed by Excess Shutdown Margin > 0.0 ppm RCS boron concentration, in MODE 1 with the OPDMS functional and in MODE 2 with keff 1.0 with the OPDMS functional.

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 CORE OPERATING LIMITS REPORT FOR VOGTLE UNIT 4 CYCLE 2 Page A-34 of 34 2.10 RCS Pressure, Temperature, and Flow Departure from Nucleate Boiling (DNB)

Limits (LCO 3.4.1)

The RCS DNB parameter limits are:

2.10.1 The Pressurizer Pressure shall be maintained greater than or equal to

[

]a,c in MODE 1.

2.10.2 The RCS Average Temperature (Tavg) shall be maintained less than or equal to

[

]a,c in MODE 1.

2.10.3 The RCS total flow rate shall be maintained greater than or equal to 301,670 gpm in MODE 1.

2.11 Boron Concentration (LCO 3.9.1)

The limit in MODE 6 for the boron concentration of the RCS, the fuel transfer canal (when connected to the RCS), and the refueling cavity (when connected to the RCS) is:

2.11.1 The boron concentration shall be maintained greater than or equal to

[

]a,c Note: The limit bounds the BOL condition of keff 0.95 (all Rod Control Cluster Assemblies inserted, all Gray Rod Control Assemblies withdrawn) and subcriticality (all rods withdrawn) over the entire cycle. This limit includes additional boron to address uncertainties and B10 depletion.

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Southern Nuclear Operating Company NL 0378 Vogtle Electric Generating Plant (VEGP) Unit 4 Westinghouse Application for Withholding Proprietary Information from Public Disclosure CAW-25-042 and accompanying Affidavit (This Enclosure consists of 4 pages, including this cover page)

Westinghouse Non-Proprietary Class 3 AFFIDAVIT CAW-25-042 Page 1 of 3 Commonwealth of Pennsylvania:

County of Butler:



I, Jerrod Ewing, Manager, Operating Plants Licensing; Cranberry Township, PA, have been

specifically delegated and authorized to apply for withholding and execute this Affidavit on

behalf of Westinghouse Electric Company LLC (Westinghouse).



I am requesting the proprietary portions of CE-25-245, Revision 0$WWDFKPHQW be withheld from publicdisclosure under 10 CFR 2.390.



I have personal knowledge of the criteria and procedures utilized by Westinghouse in

designating information as a trade secret, privileged, or as confidential commercial or

financial information.



Pursuant to 10 CFR 2.390, the following is furnished for consideration by the Commission in

determining whether the information sought to be withheld from public disclosure should be

withheld.

L

The information sought to be withheld from public disclosure is owned and has been

held in confidence by Westinghouse and is not customarily disclosed to the public.

LL

The information sought to be withheld is being transmitted to the Commission in

confidence and, to Westinghouses knowledge, is not available in public sources.

LLL

Westinghouse notes that a showing of substantial harm is no longer an applicable

criterion for analyzing whether a document should be withheld from public

disclosure. Nevertheless, public disclosure of this proprietary information is likely to

cause substantial harm to the competitive position of Westinghouse because it would

enhance the ability of competitors to provide similar technical evaluation

justifications and licensing defense services for commercial power reactors without

commensurate expenses. Also, public disclosure of the information would enable

others to use the information to meet NRC requirements for licensing documentation

without purchasing the right to use the information.

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 AFFIDAVIT CAW-25-042 Page 2 of 3 (5)

Westinghouse has policies in place to identify proprietary information. Under that system, information is held in confidence if it falls in one or more of several types, the release of which might result in the loss of an existing or potential competitive advantage, as follows:

(a)

The information reveals the distinguishing aspects of a process (or component, structure, tool, method, etc.) where prevention of its use by any of Westinghouse's competitors without license from Westinghouse constitutes a competitive economic advantage over other companies.

(b)

It consists of supporting data, including test data, relative to a process (or component, structure, tool, method, etc.), the application of which data secures a competitive economic advantage (e.g., by optimization or improved marketability).

(c)

Its use by a competitor would reduce his expenditure of resources or improve his competitive position in the design, manufacture, shipment, installation, assurance of quality, or licensing a similar product.

(d)

It reveals cost or price information, production capacities, budget levels, or commercial strategies of Westinghouse, its customers or suppliers.

(e)

It reveals aspects of past, present, or future Westinghouse or customer funded development plans and programs of potential commercial value to Westinghouse.

(f)

It contains patentable ideas, for which patent protection may be desirable.

(6)

The attached documents are bracketed and marked to indicate the bases for withholding. The justification for withholding is indicated in both versions by means of lower-case letters (a) through (f) located as a superscript immediately following the brackets enclosing each item of information being identified as proprietary or in the margin opposite such information. These lower-case letters refer to the types of information Westinghouse customarily holds in confidence identified in Sections (5)(a) through (f) of this Affidavit.

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation)

Westinghouse Non-Proprietary Class 3 AFFIDAVIT CAW-25-042 Page 3 of 3 I declare that the averments of fact set forth in this Affidavit are true and correct to the best of my knowledge, information, and belief. I declare under penalty of perjury that the foregoing is true and correct.

Executed on: 8/4/2025 Signed electronically by Jerrod Ewing

      • This record was final approved on 08/06/2025 08:52:10. (This statement was added by the PRIME system upon its validation) l s
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