JAFP-24-0034, 10 CFR 50.46 Annual Report

10 CFR 50.46 Annual Report

ML24213A006
Person / Time
Site:	FitzPatrick
Issue date:	07/31/2024
From:	David Gudger Constellation Energy Generation
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
JAFP-24-0034
Download: ML24213A006 (1)

Text

200 Energy Way Kennett Square, PA 19348 www.constellation.com

10 CFR 50.46

JAFP-24-0034

July 31, 2024

United States Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001

James A. FitzPatrick Nuclear Power Plant Renewed Facility Operating License No. DPR-59 NRC Docket No. 50-333

Subject:

10 CFR 50.46 Annual Report

The purpose of this letter is to submit the 10 CFR 50.46 reporting information for James A.

FitzPatrick Nuclear Power Plant (JAF). The most recent 10 CFR 50.46 Annual Report for JAF was provided on July 31, 2023 (JAFP-23-0043).

Three attachments are included in this letter that provide the current JAF 10 CFR 50.46 status. Attachment 1, "Peak Cladding Temperature (PCT) Rack-Up Sheet for GNF2 Fuel," and Attachment 2, "Peak Cladding Temperature (PCT) Rack-Up Sheet for GNF3 Fuel" provide updated information regarding the PCT for the limiting analysis of GNF2 Fuel and GNF3 Fuel, respectively. Attachment 3, "Assessment Notes for JAF," contains a detailed description of each change or error reported.

No new regulatory commitments are established in this submittal.

If additional information is needed, please contact Abul Hasanat at abul.hasanat@constellation.com

Respectfully,

David T. Gudger Senior Manager - Licensing & Regulatory Affairs Constellation Energy Generation, LLC

Attachments: 1) Peak Cladding Temperature Rack-Up Sheet for GNF2 Fuel

2) Peak Cladding Temperature Rack-Up Sheet for GNF3 Fuel

3) Assessment Notes for JAF

cc: USNRC Administrator, Region I USNRC Project Manager, JAF USNRC Senior Resident Inspector, JAF A. L. Peterson, NYSERDA ATTACHMENT 1

Annual Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of July 10, 2024 Peak Cladding Temperature Rack-Up Sheet for GNF2 Fuel

Annual Report of the Emergency Core Cooling System Attachment 1 Evaluation Model Changes and Errors Page 1 of 2 Assessments as of July 10, 2024 Peak Cladding Temperature Rack-Up Sheet for GNF2 Fuel

PLANT NAME: James A. FitzPatrick ECCS EVALUATION MODEL: SAFER/GESTR-LOCA supplemented with PRIME REPORT REVISION DATE: 07/10/2024 CURRENT OPERATING CYCLE: 26

ANALYSIS OF RECORD CALCULATIONS

1. 0000-0076-4111-R0, Rev. 0, James A. FitzPatrick Nuclear Power Plant GNF2 ECCS-LOCA Evaluation, August 2008 (JAF-RPT-08-00014, Rev. 0)

Fuels Analyzed in Calculations and in Operation: GNF2 Limiting Fuel Type: GNF2 Limiting Single Failure: Battery Failure Limiting Break Size and Location: Double-Ended Guillotine in a Recirculation Suction Pipe Reference Peak Cladding Temperature (PCT): GNF2 = 1800 °F

MARGIN ALLOCATION

A. PRIOR LOCA MODEL ASSESSMENTS 10 CFR 50.46 Report dated December 22, 2008 (Note 1) GNF2: PCT = 0 10 CFR 50.46 Report dated July 31, 2009 (Note 2) GNF2: PCT = 0 10 CFR 50.46 Report dated July 31, 2010 (Note 3) GNF2: PCT = 0 10 CFR 50.46 Report dated August 1, 2011 (Note 4) GNF2: PCT = 50 10 CFR 50.46 Report dated August 1, 2012 (Note 5) GNF2: PCT = 0 10 CFR 50.46 Report dated August 1, 2013 (Note 6) GNF2: PCT = 40 10 CFR 50.46 Report dated August 1, 2014 (Note 7) GNF2: PCT = 35 10 CFR 50.46 Report dated August 3, 2015 (Note 8) GNF2: PCT = -25 10 CFR 50.46 Report dated August 1, 2016 (Note 9) GNF2: PCT = 0 10 CFR 50.46 Report dated August 1, 2017 (Note 10) GNF2: PCT = 0 10 CFR 50.46 Report dated August 1, 2018 (Note 11) GNF2: PCT = 0 10 CFR 50.46 Report dated August 1, 2019 (Note 12) GNF2: PCT = 0 10 CFR 50.46 Report dated July 28, 2020 (Note 13) GNF2: PCT = 0 10 CFR 50.46 Report dated July 29, 2021 (Note 14) GNF2: PCT = 0 10 CFR 50.46 Report dated July 29, 2022 (Note 15) GNF2: PCT = 10 10 CFR 50.46 Report dated July 31, 2023 (Note 16) GNF2: PCT = 0 NET PCT GNF2: 1910 °F Annual Report of the Emergency Core Cooling System Attachment 1 Evaluation Model Changes and Errors Page 2 of 2 Assessments as of July 10, 2024 Peak Cladding Temperature Rack-Up Sheet for GNF2 Fuel

B. CURRENT LOCA MODEL ASSESSMENTS None (Note 17) GNF2: PCT = 0

Total PCT change from current assessments GNF2: PCT = 0

Cumulative PCT change from current assessments GNF2: lPCTl = 0

NET PCT GNF2: 1910 °F

ATTACHMENT 2

Annual Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of July 10, 2024 Peak Cladding Temperature Rack-Up Sheet for GNF3 Fuel

Annual Report of the Emergency Core Cooling System Attachment 2 Evaluation Model Changes and Errors Page 1 of 1 Assessments as of July 10, 2024 Peak Cladding Temperature Rack-Up Sheet for GNF3 Fuel

PLANT NAME: James A. FitzPatrick ECCS EVALUATION MODEL: SAFER/PRIME REPORT REVISION DATE: 07/10/2024 CURRENT OPERATING CYCLE: 26

ANALYSIS OF RECORD CALCULATIONS

1. 006N3902, Rev. 0, James A. FitzPatrick Nuclear Power Plant GNF3 ECCS-LOCA Evaluation, February 2022.

Fuels Analyzed in Calculations and in Operation: GNF3 Limiting Fuel Type: GNF3 Limiting Single Failure: Battery Failure Limiting Break Size and Location: Double-Ended Guillotine in a Recirculation Suction Pipe Reference Peak Cladding Temperature (PCT): GNF3 = 1880 °F

MARGIN ALLOCATION

A. PRIOR LOCA MODEL ASSESSMENTS 10 CFR 50.46 Report dated July 31, 2023 (Note 16) GNF3: PCT = 0

NET PCT GNF3: 1880 °F

B. CURRENT LOCA MODEL ASSESSMENTS None (Note 17) GNF3: PCT = 0

Total PCT change from current assessments GNF3: PCT = 0

Cumulative PCT change from current assessments GNF3: lPCTl = 0

NET PCT GNF3: 1880 °F

ATTACHMENT 3

Annual Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of July 10, 2024 Assessment Notes for JAF

Annual Report of the Emergency Core Cooling System Attachment 3 Evaluation Model Changes and Errors Page 1 of 4 Assessments as of July 10, 2024 Assessment Notes for JAF

1) Prior LOCA Model Assessment GNF2 fuel was first installed during Refueling Outage 18, October 2008.

No changes or errors were reported against GNF2 during this reporting period.

[

Reference:

Letter from E. Dorman (Entergy Nuclear Operations) to the U.S. Nuclear Regulatory Commission, JAFP-08-0133, "10 CFR 50.46 Annual Report - Errors in Emergency Core Cooling System (ECCS) Evaluation Models," dated December 22, 2008.]

2) Prior LOCA Model Assessment No changes or errors were reported against GNF2 during this reporting period.

[

Reference:

Letter from J. Pechacek (Entergy Nuclear Operations) to the U.S. Nuclear Regulatory Commission, JAFP-09-0091, "10 CFR 50.46 Annual Report - Changes and Errors in Emergency Core Cooling System (ECCS) Evaluation Models," dated July 31, 2009.]

3) Prior LOCA Model Assessment No changes or errors were reported against GNF2 during this reporting period.

[

Reference:

Letter from J. Pechacek (Entergy Nuclear Operations) to the U.S. Nuclear Regulatory Commission, JAFP-10-0084, "10 CFR 50.46 Annual Report - Changes and Errors in Emergency Core Cooling System (ECCS) Evaluation Models," dated July 31, 2010.]

4) Prior LOCA Model Assessment Two errors were reported against GNF2 fuel during this reporting period.

Error 2011-02 described the database error for heat deposition on peak cladding temperature (PCT) for 10x10 fuel bundles. The error was estimated to increase the GNF2 PCT by +45°F.

Error 2011-03 described the updated formulation for gamma heat deposition to the channel wall for 10x10 fuel bundles. The error was estimated to increase the GNF2 PCT by +5°F.

[

Reference:

Letter from Eugene W. Dorman (Entergy Nuclear Operations) to the U.S.

Nuclear Regulatory Commission, JAFP-11-0097, "10 CFR 50.46 Annual Report - Changes and Errors in Emergency Core Cooling System (ECCS) Evaluation Models," dated August 1, 2011.]

5) Prior LOCA Model Assessment No changes or errors were reported against GNF2 during this reporting period.

[

Reference:

Letter from Jorge OFarrill (Entergy Nuclear Operations) to the U.S. Nuclear Regulatory Commission, JAFP-12-0089, "10 CFR 50.46 Annual Report - Changes and Errors in Emergency Core Cooling System Evaluation Models," dated August 1, 2012.]

Annual Report of the Emergency Core Cooling System Attachment 3 Evaluation Model Changes and Errors Page 2 of 4 Assessments as of July 10, 2024 Assessment Notes for JAF

6) Prior LOCA Model Assessment One change was reported against GNF2 during this reporting period.

Change 2012-01 described the impact from PRIME implementation to compute fuel properties. The error was estimated to increase the GNF2 PCT by +40°F.

[

Reference:

Letter from Chris M. Adner (Entergy Nuclear Operations) to the U.S. Nuclear Regulatory Commission, JAFP-13-0096, "10 CFR 50.46 Annual Report - Changes and Errors in Emergency Core Cooling System Evaluation Models," dated August 1, 2013.]

7) Prior LOCA Model Assessment Four changes and errors were reported against GNF2 fuel during this reporting period.

Change 2014-01 described code maintenance changes. These changes were estimated to have no impact upon the GNF2 PCT.

Error 2014-02 described a mass non-conservatism. The error was estimated to increase the GNF2 PCT by +10°F.

Error 2014-03 described an error in the minimum core differential pressure model. The error was estimated to increase the GNF2 PCT by +20°F.

Error 2014-04 Rev 0 described an error in the bundle / lower plenum counter-current flow-limited head model. The error was estimated to increase the GNF2 PCT by +5°F.

[

Reference:

Letter from Chris M. Adner (Entergy Nuclear Operations) to the U.S. Nuclear Regulatory Commission, JAFP-14-0094, "10 CFR 50.46 Annual Report - Changes and Errors in Emergency Core Cooling System Evaluation Models," dated August 1, 2014.]

8) Prior LOCA Model Assessment One error was reported against GNF2 fuel during this reporting period.

Error 2014-04 Rev 1 was issued as a revision to error notification 2014-04 Rev 0 (Note 7).

The revision identified a change to the hot bundle pressure head used as input to the counter-current flow-limited head model that resulted in a benefit (PCT reduction). With this revised notice, the prior PCT change of +5°F was replaced by a PCT change of -20°F.

Consequently, the error was estimated to have a net change upon GNF2 PCT of -25°F.

[

Reference:

Letter from Chris M. Adner (Entergy Nuclear Operations) to the U.S. Nuclear Regulatory Commission, JAFP-15-0092, "10 CFR 50.46 Annual Report - Changes and Errors in Emergency Core Cooling System Evaluation Models," dated August 3, 2015.]

9) Prior LOCA Model Assessment No changes or errors were reported against GNF2 during this reporting period.

[

Reference:

Letter from William C. Drews (Entergy Nuclear Operations) to the U.S. Nuclear Regulatory Commission, JAFP-16-0121, "10 CFR 50.46 Annual Report - Changes and Errors in Emergency Core Cooling System Evaluation Models," dated August 1, 2016.]

Annual Report of the Emergency Core Cooling System Attachment 3 Evaluation Model Changes and Errors Page 3 of 4 Assessments as of July 10, 2024 Assessment Notes for JAF

10) Prior LOCA Model Assessment One error was reported against GNF2 during this reporting period.

Error 2017-01 identifies that the GNF2 leakage paths between the bundle and the bypass (lower tie plate flow hole and channel to lower tie plate interface) were incorrectly modeled.

The error was estimated to have no impact upon the GNF2 PCT.

[

Reference:

Letter from James Barstow (Exelon Generation) to the U.S. Nuclear Regulatory Commission, JAFP-17-0076, "10 CFR 50.46 Annual Report," dated August 1, 2017.]

11) Prior LOCA Model Assessment One error was reported against GNF2 during this reporting period.

Change 2017-02 describes a change in the GNF2 upper plenum model. The generic upper plenum model was changed to more explicitly model the GNF2 fuel design. The change was estimated to have no impact upon the GNF2 PCT.

[

Reference:

Letter from James Barstow (Exelon Generation) to the U.S. Nuclear Regulatory Commission, JAFP-18-0069, "10 CFR 50.46 Annual Report," dated August 1, 2018.]

12) Prior LOCA Model Assessment No changes or errors were reported against GNF2 during this reporting period.

[

Reference:

Letter from James Barstow (Exelon Generation) to the U.S. Nuclear Regulatory Commission, JAFP-19-0072, "10 CFR 50.46 Annual Report," dated August 1, 2019.]

13) Prior LOCA Model Assessment Notification 2019-05 identifies that the upper and lower limits for the SAFER code forward and backward bypass leakage were coded incorrectly for the control rod guide tube to control rod drive housing interface backward leakage path. The error was estimated to have zero degree upon the GNF2 PCT.

Notification 2020-01 identifies that the PRIME code contained errors in irradiation growth after a breakaway neutron fluence, thermal conductivity applied to the zirconium barrier for cladding temperature drop, and gap conductance during pellet-cladding gap closure. The errors were estimated to have zero degree impact upon the GNF2 PCT.

[

Reference:

Letter from David T. Gudger (Exelon Generation) to the U.S. Nuclear Regulatory Commission, JAFP-20-0063, "10 CFR 50.46 Annual Report," dated July 28, 2020.]

14) Prior LOCA Model Assessment Notification 2021-01 identifies an error in the fuel rod stress and perforation model due to an incorrect value used for the fuel pellet to plenum spring conductance input. The error was a result of an incorrect conversion from SI units in preparing the input for SAFER analyses. The error was estimated to have a zero degree impact upon the GNF2 PCT.

Notification 2021-02 identifies an error in the inner cladding surface roughness value in the gap conductance model. An inconsistency was identified between the roughness value used in the fuel performance model PRIME and the input to the SAFER and TRACG calculations. The error was estimated to have a zero degree impact upon the GNF2 PCT.

[

Reference:

Letter from David T. Gudger (Exelon Generation) to the U.S. Nuclear Regulatory Commission, JAFP-21-0071, "10 CFR 50.46 Annual Report," dated July 29, 2021.]

Annual Report of the Emergency Core Cooling System Attachment 3 Evaluation Model Changes and Errors Page 4 of 4 Assessments as of July 10, 2024 Assessment Notes for JAF

15) Prior LOCA Model Assessment

Notification 2021-06 identifies a process error that occurred during GNF2 New Fuel Introduction (NFI) analysis at JAF. The error was a result of only using updated fuel-related basedecks, rather than a full set of updated SAFER basedecks. This resulted in omitting updated input for the plant. The error was estimated to have a change of +10°F upon the GNF2 PCT.

It was recently discovered that a change in 2011 was made to the decay heat (DH) input used in nominal calculations for the SAFER evaluation model. The updated DH model is a best estimate decay heat curve based on the 1979 ANS 5.1 standard and considers SIL 636. This change was discovered during review of the GNF3 New Fuel Introduction and additional vendor assessments estimated an impact of 0°F upon the GNF2 PCT.

No ECCS related changes or modifications occurred at Fitzpatrick that affected the assumptions in the GNF2 LOCA analysis of record.

[

Reference:

Letter from David T. Gudger (Constellation Energy Generation, LLC) to the U.S.

Nuclear Regulatory Commission, JAFP-22-0040, "10 CFR 50.46 Annual Report," dated July 29, 2022.]

16) Prior LOCA Model Assessment

The new GE Hitachi SAFER/PRIME Evaluation Model and calculation has been implemented at FitzPatrick for the fresh GNF3 fuel loaded into the Cycle 26 core. This model reports a limiting PCT of 1880°F and has no additional PCT impacts or estimates.

The change in 2011 to the decay heat input used in the SAFER evaluation model, as discussed in Note 15, was found prior to loading GNF3 into the Cycle 26 core, but after the current Analysis of Record. However, as this change was implemented in 2011, it is already incorporated into the initial GNF3 LOCA evaluation and thus has no impact on the GNF3 LOCA analysis of record.

There were no new changes, error corrections or enhancements to the GE Hitachi SAFER/GESTR-LOCA Evaluation Model used for the GNF2 fuel loaded at JAF.

Lastly, no ECCS-related changes or modifications occurred at FitzPatrick that affected the assumptions to any of the LOCA analyses or record.

[

Reference:

Letter from David T. Gudger (Constellation Energy Generation, LLC) to the U.S.

Nuclear Regulatory Commission, JAFP-23-0043, "10 CFR 50.46 Annual Report," dated July 31, 2023.]

17) Prior LOCA Model Assessment

After the previous 10 CFR 50.46 report, no notifications were received. Likewise, no ECCS related changes or modifications occurred at FitzPatrick Unit 1 that affected the assumptions in the LOCA analyses of record.