TXX-2502, (CPNPP) - Annual Report of Changes in Peak Cladding Temperature
| ML25120A340 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 04/28/2025 |
| From: | Hicks J Vistra Operations Company |
| To: | Office of Nuclear Material Safety and Safeguards, Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| TXX-25024, CP-20250122 | |
| Download: ML25120A340 (1) | |
Text
6555 SIERRA DRIVE IRVING, TEXAS 75039 o 214-812-4600 VISTRACORP.COM Comanche Peak Nuclear Power Plant Jack C. Hicks Senior Manager, Fleet Licensing P.O. Box 1002 6322 North FM 56 Glen Rose, TX 76043 Office: 254.897.6725 CP-202500122 TXX-25024 April 28, 2025 ATTN: Document Control Desk Ref 10 CFR 50.46(a)(3)(ii)
U. S. Nuclear Regulatory Commission Washington, DC 20555-0001
Subject:
Comanche Peak Nuclear Power Plant (CPNPP)
Docket Nos. 50-445, 50-446 and 72-74 Annual Report of Changes in Peak Cladding Temperature
References:
- 1. Letter TXX-12146, dated October 18, 2012, from Rafael Flores of Luminant Power to the NRC regarding "30-Day Report for Significant Change in Peak Clad Temperature"
- 2. Letter TXX-14058, dated April 22, 2014, from Rafael Flores of Luminant Power to the NRC regarding "30-Day Report for Significant Change in Peak Clad Temperature"
Dear Sir or Madam:
Pursuant to 10CFR50.46(a)(3)(ii), Vistra Operations Company LLC (Vistra OpCo) hereby submits the attached peak cladding temperatures (PCT) for Comanche Peak Nuclear Power Plant (CPNPP), Units 1 and 2. The Large-Break Loss-of-Coolant-Accident (LBLOCA) and Small-Break Loss-of-Coolant Accident (SBLOCA) analyses for Units 1 and 2 were performed for CPNPP with the approved Westinghouse methodologies listed in Technical Specification 5.6.5. Per Reference 1, Luminant Power previously submitted information regarding fuel pellet thermal conductivity with fuel burnup in the Westinghouse Best Estimate LBLOCA analysis methodology for CPNPP Units 1 and 2. Also, per Reference 2, Luminant Power submitted information regarding an evaluation of revised Heat Transfer Multiplier Distributions, changes to Grid Blockage Ratio and Porosity, and application of a corrected Burst Strain in the Westinghouse Best Estimate LBLOCA analysis methodology for CPNPP Unit 2 and its effect on Peak Cladding Temperature (PCT).
Vistra OpCo has reviewed the notification of 10CFR50.46 reporting information pertaining to the Emergency Core Cooling System (ECCS) Evaluation Model changes that were implemented by Westinghouse. The review concludes that the effect of additional changes to, or errors in, the Evaluation Models on the limiting transient PCT were not significant.
provides an assessment of the specific changes and enhancements to the Westinghouse Evaluation Models for 2023 and 2024.
provides the calculated LBLOCA and SBLOCA PCT margin allocations in effect for the 2023 and 2024 Comanche Peak Units 1 and 2 Evaluation Models. There were no changes, error corrections, or enhancements to the 1985 Westinghouse Small Break Loss-of-Coolant Accident Evaluation Model with NOTRUMP. The PCT values determined in the LBLOCA analysis of record, combined with all of the PCT
TXX-25024 Page 2 of 2 allocations, remain well below the 10CFR50.46 regulatory limit of 2200 degrees Fahrenheit. Therefore, CPNPP Units 1 and 2 are in compliance with 10CFR50.46 requirements and no other action is required.
This communication contains no new commitments regarding CPNPP Units 1 and 2 Should you have any questions, please contact N. Boehmisch at (254) 897-5064 or nicholas.boehmisch@luminant.com.
Sincerely, Jack C. Hicks
Attachment:
- 1.
Assessments of Specific Changes and Enhancements to the Westinghouse Evaluation Models
- 2.
CPNPP Units 1 and 2 Peak Cladding Temperatures cc:
John Monninger, Region IV Uohn.Monninger@nrc.gov]
Dennis Galvin, NRR [Dennis.Galvin@nrc.gov]
John Ellegood, Senior Resident Inspector, CPNPP Uohn.Ellegood@nrc.gov]
Henry Strittmatter, Resident Inspector, CPNPP [Henry.Strittmatter@nrc.gov]
COMANCHE PEAK UNIT 2 CYCLE 21 PBOT/PMID VIOLATIONS
Background
The Comanche Peak Unit 2 Cycle 21 reload core design resulted in several violations of the PBOT/PMID box used in the Large Break LOCA analysis. These violations were evaluated for Comanche Peak Unit 2 Cycle 21 operation. This item represents a change in plant configuration or associated set points, distinguished from an evaluation model change in Section 4 of WCAP-13451.
Affected Evaluation Model(s) 2004 Westinghouse Realistic Large Break LOCA Evaluation Model Using ASTRUM Estimated Effect The impact of the PBOT/PMID violations for Comanche Peak Unit 2 Cycle 21 was determined via a plant-specific evaluation to be 0°F. to TXX-25024 1 of 11
COMANCHE PEAK UNIT 1 CYCLE 24 PBOT/PMID VIOLATIONS
Background
The Comanche Peak Unit 1 Cycle 24 reload core design resulted in several violations of the PBOT/PMID box used in the Large Break LOCA analysis. These violations were evaluated for Comanche Peak Unit 1 Cycle 24 operation. This item represents a change in plant configuration or associated set points, distinguished from an evaluation model change in Section 4 of WCAP-13451.
Affected Evaluation Model(s) 2004 Westinghouse Realistic Large Break LOCA Evaluation Model Using ASTRUM Estimated Effect The impact of the PBOT/PMID violations for Comanche Peak Unit 1 Cycle 24 was determined via a plant-specific evaluation to be 0°F. to TXX-25024 2 of 11
ERROR IN FLOW AREA AND VOLUME OF THIMBLE COMPONENTS
Background
The reactor vessel thimble bypass flow is modeled in best-estimate (BE) loss-of-coolant accident (LOCA) analyses using three PIPE components, which represent the thimble bypass for peripheral low power assemblies, interior assemblies located under guide tubes, and interior assemblies not located under guide tubes. It was discovered that the number of assemblies modeled is inconsistent with the number of assemblies represented by one or more of the thimble components, leading to an incorrect flow area and volume for the affected thimble component(s). The correction of this error represents a Non-Discretionary Change in accordance with Section 4.1.2 of WCAP-13451.
Affected Evaluation Model(s) 2004 Westinghouse Realistic Large Break LOCA Evaluation Model Using ASTRUM 2016 Westinghouse FULL SPECTRUMTM LOCA Evaluation Model Estimated Effect The error was evaluated to have a negligible impact on the calculated results, leading to an estimated peak cladding temperature (PCT) impact of 0°F. to TXX-25024 3 of 11
GENERAL CODE MAINTENANCE
Background
Various changes have been made to enhance the usability of codes and to streamline future analyses. Examples of these changes include improving the input diagnostic checks; enhancing the code output; optimizing active coding; and eliminating inactive coding. These changes represent Discretionary Changes that will be implemented on a forward-fit basis in accordance with Section 4.1.1 of WCAP-13451.
Affected Evaluation Model(s) 2004 Westinghouse Realistic Large Break LOCA Evaluation Model Using ASTRUM 2016 Westinghouse FULL SPECTRUM LOCA Evaluation Model Estimated Effect The nature of these changes leads to an estimated peak cladding temperature impact of 0°F. to TXX-25024 4 of 11
VAPOR / CONTINUOUS LIQUID INTERFACIAL DRAG COEFICIENT IN CHURN-TURBULENT FLOW REGIME
Background
Two deficiencies were identified in the calculation of the churn-turbulent vapor / continuous liquid interfacial drag coefficient calculation within WCOBRA/TRAC-TF2 due to the potential calculation of a negative critical liquid fraction. The negative critical liquid fraction results in an over-prediction of the vapor / continuous liquid interfacial area and a negative vapor / continuous liquid interfacial drag coefficient which leads to a significantly large interfacial drag coefficient (i.e., no slip). These items represent a closely-related group of Non-Discretionary Changes in accordance with Section 4.1.2 of WCAP-13451.
Affected Evaluation Model(s) 2016 Westinghouse FULL SPECTRUM LOCA Evaluation Model Estimated Effect The closely-related group of deficiencies was qualitatively evaluated, and the nature of the deficiencies leads to an estimated peak cladding temperature impact of 0°F. to TXX-25024 5 of 11
LUCIFER KINETICS AND DECAY HEAT MODEL
Background
The kinetics and decay heat models in the WCOBRA/TRAC-TF2 code are described in Section 9 of WCAP-16996-P-A, Revision 1. The nuclear physics data supporting the code models was generated as described in the response to Request for Additional Information (RAI) #25 on the FSLOCATM EM.
Since the approval of the FSLOCA EM, the kinetics and decay heat model in the WCOBRA/TRAC-TF2 code was updated to support the analysis of higher burnup fuel as described in Section 4.6 of WCAP-18446-P and the supplemental response to Request for Additional Information 23.2 in LTR-NRC-22-47.
While the primary purpose of the kinetics and decay heat model update is for the analysis of higher burnup fuel, the change will minimally impact licensing basis analysis calculations with the FSLOCA EM under the existing burnup limits imposed via Limitation and Condition (L&C) #5 on the FSLOCA EM.
This change to the WCOBRA/TRAC-TF2 code represents a Discretionary Change that will be implemented on a forward-fit basis in accordance with Section 4.1.1 of WCAP-13451.
Affected Evaluation Model(s) 2016 Westinghouse FULL SPECTRUM LOCA Evaluation Model Estimated Effect This change will be implemented in a forward-fit manner and has no effect on existing analyses. to TXX-25024 6 of 11
PELLET RADIAL NODING CONSISTENT WITH PAD5
Background
The fuel rod radial noding in the WCOBRA/TRAC-TF2 code is described in Sections 8.2 and 8.4 of WCAP-16996-P-A, Revision 1. The fuel rod radial noding was updated to be consistent with the PAD5 code (WCAP-17642-P-A, Revision 1) regarding the size and number of the nodes. This change represents a Discretionary Change that will be implemented on a forward-fit basis in accordance with Section 4.1.1 of WCAP-13451.
Affected Evaluation Model(s) 2016 Westinghouse FULL SPECTRUM LOCA Evaluation Model Estimated Effect This change will be implemented in a forward-fit manner and has no effect on existing analyses. to TXX-25024 7 of 11
GENERAL CODE MAINTENANCE
Background
Various changes have been made to enhance the usability of codes and to streamline future analyses. Examples of these changes include improving the input diagnostic checks; enhancing the code output; optimizing active coding; and eliminating inactive coding. These changes represent Discretionary Changes that will be implemented on a forward-fit basis in accordance with Section 4.1.1 of WCAP-13451.
Affected Evaluation Model(s) 2016 Westinghouse FULL SPECTRUMTM LOCA Evaluation Model Estimated Effect The nature of these changes leads to an estimated peak cladding temperature impact of 0°F. to TXX-25024 8 of 11
STEAM/FISSION GAS SPECIFIC HEAT CALCULATION
Background
An error was identified in WCOBRA/TRAC-TF2 related to an incorrect specific heat value used in the calculation of superheated steam thermal conductivity as part of the post-burst pellet-to-cladding gap heat transfer calculation. The incorrect specific heat value results in the superheated steam thermal conductivity being slightly under-predicted at the burst node after rupture is predicted. This leads to a minimal reduction in the gap conductance and slight over-prediction of the fuel average temperatures at the rod burst location after burst is predicted. This error represents a Non-Discretionary Change in accordance with Section 4.1.2 of WCAP-13451.
Affected Evaluation Model(s) 2016 Westinghouse FULL SPECTRUM LOCA Evaluation Model Estimated Effect The deficiency was qualitatively evaluated, and the nature of the error leads to an estimated peak cladding temperature impact of 0°F. to TXX-25024 9 of 11
BARREL/BAFFLE REGION VOLUME ERROR
Background
An error was identified during the course of a recent Best Estimate Large Break LOCA analysis in which the volume between the core barrel and the baffle plates within the active fuel length was modeled incorrectly. The corrected values have been evaluated for impact on the current licensing-basis analysis results. The correction of this error represents a Non-Discretionary Change in accordance with Section 4.1.2 of WCAP-13451.
Affected Evaluation Model(s) 2004 Westinghouse Realistic Large Break LOCA Evaluation Model Using ASTRUM 2016 Westinghouse FULL SPECTRUM LOCA Evaluation Model Estimated Effect The error was evaluated to have a negligible impact on the calculated results, leading to an estimated peak cladding temperature (PCT) impact of 0°F. to TXX-25024 10 of 11
CCFL GLOBAL VOLUME ERROR
Background
An error was identified during the course of a recent Best Estimate Large Break LOCA analysis in which the volume in the global channel in the CCFL region above the active fuel length was modeled incorrectly. The corrected values have been evaluated for impact on the current licensing-basis analysis results. This error represents a non-discretionary change in accordance with Section 4.1.2 of WCAP-13451.
Affected Evaluation Model(s) 2016 Westinghouse FULL SPECTRUM LOCA Evaluation Model Estimated Effect The CCFL global volume modeling error has been generically evaluated to have a negligible impact on PCT for affected analyses, leading to an estimate peak cladding temperature (PCT) impact of 0°F. to TXX-25024 11 of 11
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 1 EM:
NOTRUMP AOR
Description:
Appendix K Small Break Summary Sheet Status: Current COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_Appendix_K_SBLOCA - 1.1 V.V PCT (°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1013 1
1013.0 °F REFERENCES 1
WCAP-16840-P, Comanche Peak Nuclear Power Plant Stretch Power Uprate Licensing Report, August 2007.
NOTES:
(a) None Version: COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_Appendix_K_SBLOCA - 1.1 V.V to TXX-25024 1 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 1 EM:
ASTRUM (2004)
Description:
Best Estimate Large Break Summary Sheet Status: Current COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_ASTRUM - 1.1 V.V PCT (°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1492 1
ASSESSMENTS*
Delta PCT
(°F)
Reference #
Note #
Reporting Year**
1.
Evaluation of Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown 122 2
(a) 2012 2.
Revised Heat Transfer Multiplier Distributions
-6 3
2013 3.
Error in Burst Strain Application 21 4
1629.0 °F The licensee should determine the reportability of these assessments pursuant to 10 CFR 50.46.
- The Reporting Year refers to the annual reporting year in which this assessment was included.
REFERENCES 1
WCAP-16762-P, Revision 1, Best-Estimate Analysis of the Large-Break Loss-of-Coolant Accident for the Comanche Peak Nuclear Power Plant Unit 1 Using the ASTRUM Methodology, March 2009.
2 LTR-LIS-12-410, Comanche Peak Units 1 and 2 10 CFR 50.46 Notification and Reporting for Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown, September 2012.
3 LTR-LIS-13-359, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for Revised Heat Transfer Multiplier Distributions, July 2013.
4 LTR-LIS-14-43, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for the HOTSPOT Burst Strain Error Correction, January 2014.
NOTES:
(a) This evaluation credits peaking factor burndown, see Reference 2.
Version: COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_ASTRUM - 1.1 V.V to TXX-25024 2 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 1 EM:
ASTRUM (2004)
Description:
Best Estimate Large Break Summary Sheet Status: Cycle 23 - Retired 2023 COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Cycle_23_ASTRUM_1.2 V.V PCT(°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1492 1
ASSESSMENTS*
Delta PCT
(°F)
Reference #
Note #
Reporting Year**
1.
Evaluation of Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown 122 3
(a) 2012 2.
Revised Heat Transfer Multiplier Distributions
-6 4
2013 3.
Error in Burst Strain Application 21 5
2013 4.
PBOT/PMID Violation 0
2 2022 AOR + ASSESSMENTS PCT =
1629 °F The licensee should determine the reportability of these assessments pursuant to 10 CFR 50.46.
- The Reporting Year refers to the annual reporting year in which this assessment was included.
REFERENCES 1.
WCAP-16762-P, Revision 1, Best-Estimate Analysis of the Large-Break Loss-of-Coolant Accident for the Comanche Peak Nuclear Power Plant Unit 1 Using the ASTRUM Methodology, March 2009.
2.
TBX-LOCA-TM-A5-000001, 10 CFR 50.46 Reporting Text and LBLOCA PCT Summary Sheet Update for the Evaluation of the Comanche Peak Unit 1 Cycle 23 PBOT/PMID Violations, March 2022.
3.
LTR-LIS-12-410, Comanche Peak Units 1 and 2 10 CFR 50.46 Notification and Reporting for Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown, September 2012.
4.
LTR-LIS-13-359, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for Revised Heat Transfer Multiplier Distributions, July 2013.
5.
LTR-LIS-14-43, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for the HOTSPOT Burst Strain Error Correction, January 2014.
NOTES:
(a) This evaluation credits peaking factor burndown, see Reference 3.
Version: COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Cycle_23_ASTRUM_1.2 V.V to TXX-25024 3 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 1 EM:
ASTRUM (2004)
Description:
Best Estimate Large Break Summary Sheet Status: Cycle 24 COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Cycle_24_ASTRUM_1.1 V.V PCT(°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1492 1
ASSESSMENTS*
Delta PCT
(°F)
Reference #
Note #
Reporting Year**
1.
Evaluation of Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown 122 3
(a) 2012 2.
Revised Heat Transfer Multiplier Distributions
-6 4
2013 3.
Error in Burst Strain Application 21 5
2013 4.
PBOT/PMID Violation 0
2 2023 AOR + ASSESSMENTS PCT =
1629 °F The licensee should determine the reportability of these assessments pursuant to 10 CFR 50.46.
- The Reporting Year refers to the annual reporting year in which this assessment was included.
REFERENCES 1.
WCAP-16762-P, Revision 1, Best-Estimate Analysis of the Large-Break Loss-of-Coolant Accident for the Comanche Peak Nuclear Power Plant Unit 1 Using the ASTRUM Methodology, March 2009.
2.
TBX-LOCA-TM-A5-000002, 10 CFR 50.46 Reporting Text and LBLOCA PCT Summary Sheet Update for the Evaluation of the Comanche Peak Unit 1 Cycle 24 PBOT/PMID Violations, October 2023.
3.
LTR-LIS-12-410, Comanche Peak Units 1 and 2 10 CFR 50.46 Notification and Reporting for Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown, September 2012.
4.
LTR-LIS-13-359, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for Revised Heat Transfer Multiplier Distributions, July 2013.
5.
LTR-LIS-14-43, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for the HOTSPOT Burst Strain Error Correction, January 2014.
NOTES:
(a) This evaluation credits peaking factor burndown, see Reference 3.
Version: COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Cycle_24_ASTRUM_1.1 V.V to TXX-25024 4 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 2 EM:
NOTRUMP AOR
Description:
Appendix K Small Break Summary Sheet Status: Current COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_Appendix_K_SBLOCA - 1.1 V.V PCT (°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1210 1
1210.0 °F REFERENCES 1
WCAP-16840-P, Comanche Peak Nuclear Power Plant Stretch Power Uprate Licensing Report, August 2007.
NOTES:
(a) None Version: COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_Appendix_K_SBLOCA - 1.1 V.V to TXX-25024 5 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 2 EM:
ASTRUM (2004)
Description:
Best Estimate Large Break Summary Sheet Status: Current COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_ASTRUM - 1.1 V.V PCT (°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1632 1
ASSESSMENTS*
Delta PCT
(°F)
Reference #
Note #
Reporting Year**
1.
Evaluation of Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown 190 2
(a) 2012 2.
Revised Heat Transfer Multiplier Distributions
-17 3
2013 3.
Changes to Grid Blockage Ratio and Porosity 24 4
2013 4.
Error in Burst Strain Application 21 5
1850.0 °F The licensee should determine the reportability of these assessments pursuant to 10 CFR 50.46.
- The Reporting Year refers to the annual reporting year in which this assessment was included.
REFERENCES 1
WCAP-16763-P, Revision 1, Best-Estimate Analysis of the Large-Break Loss-of-Coolant Accident for the Comanche Peak Nuclear Power Plant Unit 2 Using the ASTRUM Methodology, March 2009.
2 LTR-LIS-12-410, Comanche Peak Units 1 and 2 10 CFR 50.46 Notification and Reporting for Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown, September 2012.
3 LTR-LIS-13-359, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for Revised Heat Transfer Multiplier Distributions, July 2013.
4 LTR-LIS-13-472, Comanche Peak Units 1 and 2 10 CFR 50.46 Reports for Changes to Grid Blockage Ratio and Porosity, October 2013.
5 LTR-LIS-14-43, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for the HOTSPOT Burst Strain Error Correction, January 2014.
Version: COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_ASTRUM - 1.1 V.V NOTES:
(a) This evaluation credits peaking factor burndown, see Reference 2. to TXX-25024 6 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 2 EM:
ASTRUM (2004)
Description:
Best Estimate Large Break Summary Sheet Status: Cycle 20 - Retired 2023 COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Cycle_20_ASTRUM_1.2 V.V PCT(°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1632 1
ASSESSMENTS*
Delta PCT
(°F)
Reference #
Note #
Reporting Year**
1.
Evaluation of Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown 190 3
(a) 2012 2.
Revised Heat Transfer Multiplier Distributions
-17 4
2013 3.
Changes to Grid Blockage Ratio and Porosity 24 5
2013 4.
Error in Burst Strain Application 21 6
2013 5.
PBOT/PMID Violation 0
2 2021 AOR + ASSESSMENTS PCT =
1850 °F The licensee should determine the reportability of these assessments pursuant to 10 CFR 50.46.
- The Reporting Year refers to the annual reporting year in which this assessment was included.
REFERENCES 1.
WCAP-16763-P, Revision 1, Best-Estimate Analysis of the Large-Break Loss-of-Coolant Accident for the Comanche Peak Nuclear Power Plant Unit 2 Using the ASTRUM Methodology, March 2009.
2.
TCX-LOCA-TM-A5-000001, 10 CFR 50.46 Reporting Text and LBLOCA PCT Summary Sheet Update for the Evaluation of the Comanche Peak Unit 2 Cycle 20 PBOT/PMID Violations, September 2021.
3.
LTR-LIS-12-410, Comanche Peak Units 1 and 2 10 CFR 50.46 Notification and Reporting for Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown, September 2012.
4.
LTR-LIS-13-359, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for Revised Heat Transfer Multiplier Distributions, July 2013.
5.
LTR-LIS-13-472, Comanche Peak Units 1 and 2 10 CFR 50.46 Reports for Changes to Grid Blockage Ratio and Porosity, October 2013.
6.
LTR-LIS-14-43, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for the HOTSPOT Burst Strain Error Correction, January 2014.
Version: COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Cycle_20_ASTRUM_1.2 V.V NOTES:
(a) This evaluation credits peaking factor burndown, see Reference 3. to TXX-25024 7 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 2 EM:
ASTRUM (2004)
Description:
Best Estimate Large Break Summary Sheet Status: Cycle 21 COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Cycle_21_ASTRUM_1.1 V.V PCT(°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1632 1
ASSESSMENTS*
Delta PCT
(°F)
Reference #
Note #
Reporting Year**
1.
Evaluation of Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown 190 3
(a) 2012 2.
Revised Heat Transfer Multiplier Distributions
-17 4
2013 3.
Changes to Grid Blockage Ratio and Porosity 24 5
2013 4.
Error in Burst Strain Application 21 6
2013 5.
PBOT/PMID Violation 0
2 2023 AOR + ASSESSMENTS PCT =
1850 °F The licensee should determine the reportability of these assessments pursuant to 10 CFR 50.46.
- The Reporting Year refers to the annual reporting year in which this assessment was included.
REFERENCES 1.
WCAP-16763-P, Revision 1, Best-Estimate Analysis of the Large-Break Loss-of-Coolant Accident for the Comanche Peak Nuclear Power Plant Unit 2 Using the ASTRUM Methodology, March 2009.
2.
TCX-LOCA-TM-A5-000002, 10 CFR 50.46 Reporting Text and LBLOCA PCT Summary Sheet Update for the Evaluation of the Comanche Peak Unit 2 Cycle 21 PBOT/PMID Violations, April 2023.
3.
LTR-LIS-12-410, Comanche Peak Units 1 and 2 10 CFR 50.46 Notification and Reporting for Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown, September 2012.
4.
LTR-LIS-13-359, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for Revised Heat Transfer Multiplier Distributions, July 2013.
5.
LTR-LIS-13-472, Comanche Peak Units 1 and 2 10 CFR 50.46 Reports for Changes to Grid Blockage Ratio and Porosity, October 2013.
6.
LTR-LIS-14-43, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for the HOTSPOT Burst Strain Error Correction, January 2014.
Version: COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Cycle_21_ASTRUM_1.1 V.V NOTES:
(a) This evaluation credits peaking factor burndown, see Reference 3. to TXX-25024 8 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 1 EM:
FSLOCA AOR
Description:
FULL SPECTRUM LOCA EM Large Break Summary Sheet Status: Future COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_FSLOCA_LBLOCA - 1.2 V.V PCT (°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1566 1
(a)
1566.0 °F REFERENCES 1
WCAP-18417-P, Engineering Summary Report of the Comanche Peak Unit 1 Loss-of-Coolant Accident (LOCA) Analysis with the FULL SPECTRUM LOCA (FSLOCA) Methodology, February 2019.
NOTES:
(a) The analysis-of-record PCT reflects the uncertainty analysis that included the error in gamma energy redistribution uncertainty (1546°F) as well as the correction of the error (20°F).
Version: COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_FSLOCA_LBLOCA - 1.2 V.V to TXX-25024 9 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 1 EM:
FSLOCA AOR
Description:
FULL SPECTRUM LOCA EM Small Break Summary Sheet Status: Future COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_FSLOCA_SBLOCA - 1.2 V.V PCT (°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1032 1
(a)
1032.0 °F REFERENCES 1
WCAP-18417-P, Engineering Summary Report of the Comanche Peak Unit 1 Loss-of-Coolant Accident (LOCA) Analysis with the FULL SPECTRUM LOCA (FSLOCA) Methodology, February 2019.
NOTES:
(a) The analysis-of-record PCT reflects the uncertainty analysis that included the error in gamma energy redistribution uncertainty (1017°F) as well as the correction of the error (15°F).
Version: COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_FSLOCA_SBLOCA - 1.2 V.V to TXX-25024 10 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 2 EM:
FSLOCA AOR
Description:
FULL SPECTRUM LOCA EM Large Break Summary Sheet Status: Future COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_FSLOCA_LBLOCA - 1.2 V.V PCT (°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1610 1
(a)
1610.0 °F REFERENCES 1
WCAP-18418-P, Engineering Summary Report of the Comanche Peak Unit 2 Loss-of-Coolant Accident (LOCA) Analysis with the FULL SPECTRUM LOCA (FSLOCA) Methodology, March 2019.
NOTES:
(a) The analysis-of-record PCT reflects the uncertainty analysis that included the error in gamma energy redistribution uncertainty (1579°F) as well as the correction of the error (31°F).
Version: COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_FSLOCA_LBLOCA - 1.2 V.V to TXX-25024 11 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 2 EM:
FSLOCA AOR
Description:
FULL SPECTRUM LOCA EM Small Break Summary Sheet Status: Future COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_FSLOCA_SBLOCA - 1.3 V.V PCT (°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1116 1
(a)
1116.0 °F REFERENCES 1
WCAP-18418-P, Engineering Summary Report of the Comanche Peak Unit 2 Loss-of-Coolant Accident (LOCA) Analysis with the FULL SPECTRUM LOCA (FSLOCA) Methodology, March 2019.
NOTES:
(a) The analysis-of-record PCT reflects the uncertainty analysis that included the error in gamma energy redistribution uncertainty (1113°F) as well as the correction of the error (3°F).
Version: COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_FSLOCA_SBLOCA - 1.3 V.V to TXX-25024 12 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 1 EM:
NOTRUMP AOR
Description:
Appendix K Small Break Summary Sheet Status: Current COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_Appendix_K_SBLOCA - 1.1 V.V PCT (°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1013 1
1013.0 °F REFERENCES 1
WCAP-16840-P, Comanche Peak Nuclear Power Plant Stretch Power Uprate Licensing Report, August 2007.
NOTES:
(a) None Version: COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_Appendix_K_SBLOCA - 1.1 V.V to TXX-25024 13 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 1 EM:
ASTRUM (2004)
Description:
Best Estimate Large Break Summary Sheet Status: Current COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_ASTRUM - 1.1 V.V PCT (°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1492 1
ASSESSMENTS*
Delta PCT
(°F)
Reference #
Note #
Reporting Year**
1.
Evaluation of Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown 122 2
(a) 2012 2.
Revised Heat Transfer Multiplier Distributions
-6 3
2013 3.
Error in Burst Strain Application 21 4
1629.0 °F The licensee should determine the reportability of these assessments pursuant to 10 CFR 50.46.
- The Reporting Year refers to the annual reporting year in which this assessment was included.
REFERENCES 1
WCAP-16762-P, Revision 1, Best-Estimate Analysis of the Large-Break Loss-of-Coolant Accident for the Comanche Peak Nuclear Power Plant Unit 1 Using the ASTRUM Methodology, March 2009.
2 LTR-LIS-12-410, Comanche Peak Units 1 and 2 10 CFR 50.46 Notification and Reporting for Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown, September 2012.
3 LTR-LIS-13-359, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for Revised Heat Transfer Multiplier Distributions, July 2013.
4 LTR-LIS-14-43, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for the HOTSPOT Burst Strain Error Correction, January 2014.
NOTES:
(a) This evaluation credits peaking factor burndown, see Reference 2.
Version: COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_ASTRUM - 1.1 V.V to TXX-25024 14 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 1 EM:
ASTRUM (2004)
Description:
Best Estimate Large Break Summary Sheet Status: Cycle 24 COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Cycle_24_ASTRUM_1.1 V.V PCT(°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1492 1
ASSESSMENTS*
Delta PCT
(°F)
Reference #
Note #
Reporting Year**
1.
Evaluation of Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown 122 3
(a) 2012 2.
Revised Heat Transfer Multiplier Distributions
-6 4
2013 3.
Error in Burst Strain Application 21 5
2013 4.
PBOT/PMID Violation 0
2 2023 AOR + ASSESSMENTS PCT =
1629 °F The licensee should determine the reportability of these assessments pursuant to 10 CFR 50.46.
- The Reporting Year refers to the annual reporting year in which this assessment was included.
REFERENCES 1.
WCAP-16762-P, Revision 1, Best-Estimate Analysis of the Large-Break Loss-of-Coolant Accident for the Comanche Peak Nuclear Power Plant Unit 1 Using the ASTRUM Methodology, March 2009.
2.
TBX-LOCA-TM-A5-000002, 10 CFR 50.46 Reporting Text and LBLOCA PCT Summary Sheet Update for the Evaluation of the Comanche Peak Unit 1 Cycle 24 PBOT/PMID Violations, October 2023.
3.
LTR-LIS-12-410, Comanche Peak Units 1 and 2 10 CFR 50.46 Notification and Reporting for Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown, September 2012.
4.
LTR-LIS-13-359, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for Revised Heat Transfer Multiplier Distributions, July 2013.
5.
LTR-LIS-14-43, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for the HOTSPOT Burst Strain Error Correction, January 2014.
NOTES:
(a) This evaluation credits peaking factor burndown, see Reference 3.
Version: COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Cycle_24_ASTRUM_1.1 V.V to TXX-25024 15 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 2 EM:
NOTRUMP AOR
Description:
Appendix K Small Break Summary Sheet Status: Retired 2024 COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_Appendix_K_SBLOCA_1.2 V.V PCT(°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1210 1
1210.0 °F REFERENCES 1.
WCAP-16840-P, Comanche Peak Nuclear Power Plant Stretch Power Uprate Licensing Report, August 2007.
NOTES:
(a) None Version: COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_Appendix_K_SBLOCA_1.2 V.V to TXX-25024 16 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 2 EM:
ASTRUM (2004)
Description:
Best Estimate Large Break Summary Sheet Status: Retired 2024 COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_ASTRUM_1.2 V.V PCT(°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1632 1
ASSESSMENTS*
Delta PCT
(°F)
Reference #
Note #
Reporting Year**
1.
Evaluation of Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown 190 2
(a) 2012 2.
Revised Heat Transfer Multiplier Distributions
-17 3
2013 3.
Changes to Grid Blockage Ratio and Porosity 24 4
2013 4.
Error in Burst Strain Application 21 5
1850.0 °F The licensee should determine the reportability of these assessments pursuant to 10 CFR 50.46.
- The Reporting Year refers to the annual reporting year in which this assessment was included.
REFERENCES 1.
WCAP-16763-P, Revision 1, Best-Estimate Analysis of the Large-Break Loss-of-Coolant Accident for the Comanche Peak Nuclear Power Plant Unit 2 Using the ASTRUM Methodology, March 2009.
2.
LTR-LIS-12-410, Comanche Peak Units 1 and 2 10 CFR 50.46 Notification and Reporting for Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown, September 2012.
3.
LTR-LIS-13-359, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for Revised Heat Transfer Multiplier Distributions, July 2013.
4.
LTR-LIS-13-472, Comanche Peak Units 1 and 2 10 CFR 50.46 Reports for Changes to Grid Blockage Ratio and Porosity, October 2013.
5.
LTR-LIS-14-43, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for the HOTSPOT Burst Strain Error Correction, January 2014.
Version: COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_ASTRUM_1.2 V.V NOTES:
(a) This evaluation credits peaking factor burndown, see Reference 2. to TXX-25024 17 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 2 EM:
ASTRUM (2004)
Description:
Best Estimate Large Break Summary Sheet Status: Cycle 21 - Retired 2024 COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Cycle_21_ASTRUM_1.2 V.V PCT(°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1632 1
ASSESSMENTS*
Delta PCT
(°F)
Reference #
Note #
Reporting Year**
1.
Evaluation of Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown 190 3
(a) 2012 2.
Revised Heat Transfer Multiplier Distributions
-17 4
2013 3.
Changes to Grid Blockage Ratio and Porosity 24 5
2013 4.
Error in Burst Strain Application 21 6
2013 5.
PBOT/PMID Violation 0
2 2023 AOR + ASSESSMENTS PCT =
1850 °F The licensee should determine the reportability of these assessments pursuant to 10 CFR 50.46.
- The Reporting Year refers to the annual reporting year in which this assessment was included.
REFERENCES 1.
WCAP-16763-P, Revision 1, Best-Estimate Analysis of the Large-Break Loss-of-Coolant Accident for the Comanche Peak Nuclear Power Plant Unit 2 Using the ASTRUM Methodology, March 2009.
2.
TCX-LOCA-TM-A5-000002, 10 CFR 50.46 Reporting Text and LBLOCA PCT Summary Sheet Update for the Evaluation of the Comanche Peak Unit 2 Cycle 21 PBOT/PMID Violations, April 2023.
3.
LTR-LIS-12-410, Comanche Peak Units 1 and 2 10 CFR 50.46 Notification and Reporting for Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown, September 2012.
4.
LTR-LIS-13-359, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for Revised Heat Transfer Multiplier Distributions, July 2013.
5.
LTR-LIS-13-472, Comanche Peak Units 1 and 2 10 CFR 50.46 Reports for Changes to Grid Blockage Ratio and Porosity, October 2013.
6.
LTR-LIS-14-43, Comanche Peak Units 1 and 2 10 CFR 50.46 Report for the HOTSPOT Burst Strain Error Correction, January 2014.
Version: COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Cycle_21_ASTRUM_1.2 V.V NOTES:
(a) This evaluation credits peaking factor burndown, see Reference 3. to TXX-25024 18 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 1 EM:
FSLOCATM AOR
Description:
FULL SPECTRUM LOCA EM Large Break Summary Sheet Status: Future COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_FSLOCA_LBLOCA - 1.2 V.V PCT (°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1566 1
(a)
1566.0 °F REFERENCES 1
WCAP-18417-P, Engineering Summary Report of the Comanche Peak Unit 1 Loss-of-Coolant Accident (LOCA) Analysis with the FULL SPECTRUM LOCA (FSLOCA) Methodology, February 2019.
NOTES:
(a) The analysis-of-record PCT reflects the uncertainty analysis that included the error in gamma energy redistribution uncertainty (1546°F) as well as the correction of the error (20°F).
Version: COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_FSLOCA_LBLOCA - 1.2 V.V to TXX-25024 19 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 1 EM:
FSLOCA AOR
Description:
FULL SPECTRUM LOCA EM Small Break Summary Sheet Status: Future COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_FSLOCA_SBLOCA - 1.2 V.V PCT (°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1032 1
(a)
1032.0 °F REFERENCES 1
WCAP-18417-P, Engineering Summary Report of the Comanche Peak Unit 1 Loss-of-Coolant Accident (LOCA) Analysis with the FULL SPECTRUM LOCA (FSLOCA) Methodology, February 2019.
NOTES:
(a) The analysis-of-record PCT reflects the uncertainty analysis that included the error in gamma energy redistribution uncertainty (1017°F) as well as the correction of the error (15°F).
Version: COMANCHE PEAK 1 TBX_LOCA-50.46_TBX_Base_FSLOCA_SBLOCA - 1.2 V.V to TXX-25024 20 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 2 EM:
FSLOCA AOR
Description:
FULL SPECTRUM LOCA EM Small Break Summary Sheet Status: Current COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_FSLOCA_SBLOCA_1.4 V.V PCT(°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1116 1
(a)
1116 °F REFERENCES 1.
WCAP-18418-P, Engineering Summary Report of the Comanche Peak Unit 2 Loss-of-Coolant Accident (LOCA) Analysis with the FULL SPECTRUM LOCA (FSLOCA) Methodology, March 2019.
NOTES:
(a) The analysis-of-record PCT reflects the uncertainty analysis that included the error in gamma energy redistribution uncertainty (1113°F) as well as the correction of the error (3°F).
Version: COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_FSLOCA_SBLOCA_1.4 V.V to TXX-25024 21 of 22
LOCA Peak Cladding Temperature (PCT) Summary Plant Name:
COMANCHE PEAK 2 EM:
FSLOCA AOR
Description:
FULL SPECTRUM LOCA EM Large Break Summary Sheet Status: Current COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_FSLOCA_LBLOCA_1.3 V.V PCT(°F)
Reference #
Note #
ANALYSIS-OF-RECORD 1610 1
(a)
1610 °F REFERENCES 1.
WCAP-18418-P, Engineering Summary Report of the Comanche Peak Unit 2 Loss-of-Coolant Accident (LOCA) Analysis with the FULL SPECTRUM LOCA (FSLOCA) Methodology, March 2019.
NOTES:
(a) The analysis-of-record PCT reflects the uncertainty analysis that included the error in gamma energy redistribution uncertainty (1579°F) as well as the correction of the error (31°F).
Version: COMANCHE PEAK 2 TCX_LOCA-50.46_TCX_Base_FSLOCA_LBLOCA_1.3 V.V to TXX-25024 22 of 22