ML25192A006
| ML25192A006 | |
| Person / Time | |
|---|---|
| Site: | Electric Power Research Institute |
| Issue date: | 07/15/2025 |
| From: | Delosreyes J Licensing Processes Branch |
| To: | Electric Power Research Institute |
| References | |
| Download: ML25192A006 (1) | |
Text
1 REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION REVIEW OF (3002028674/5) EPRI ANALYSIS LOCA-INDUCED FFRD FOR 2/3/4-LOOP WESTINGHOUSE PLANTS (NON-BILLABLE)
EPRI SDA DOCKET NO. 99902021 ISSUE DATE: 07/15/2025
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Background===
By letter dated April 26, 2024 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML24121A203), Electric Power Research Institute (EPRI) submitted EPRI Report 3002028674 (P)/3002028675 (NP), "LOCA Analyses of Fuel Fragmentation, Relocation, and Dispersal for Westinghouse 2-Loop, 3-Loop, and 4-Loop Plants - Proprietary, Evaluation of Cladding Rupture in High Burnup Fuel Rods susceptible to Fine Fragmentation,"
(henceforth EPRI Report 3002028674/5) to the U.S. Nuclear Regulatory Commission (NRC) for review and approval. EPRI Report 3002028674/5 proposes to demonstrate acceptable performance for LOCA-induced FFRD phenomena in high burnup PWR fuel by developing bounding composite models and utilizing the cladding rupture methodology proposed in WCAP-18850-P/NP, Revision 0, "Adaptation of the FULL SPECTRUM LOCA (FSLOCA) Evaluation Methodology to Perform Analysis of Cladding Rupture for High Burnup Fuel." The NRC staff has reviewed EPRI Report 3002028674/5, conducted a regulatory audit on January 24, 2025, and determined that additional information is required to complete the review.
Regulatory Basis The NRC staff is reviewing EPRI Report 3002028674/5 to ensure compliance with the requirements associated with the postulated loss-of-coolant accident (LOCA), including Title 10 of the Code of Federal Regulations (CFR) 50.46 and General Design Criteria 35. The purpose of EPRI Report 3002028674/5 is to develop bounding composite PWR plant models to demonstrate acceptable performance with respect to LOCA-induced FFRD for high-burnup fuel rods susceptible to fine fragmentation. Assuring acceptable margin to cladding rupture for high-burnup fuel is a means of demonstrating compliance with existing requirements for the LOCA, including the requirement in 10 CFR 50.46(b)(4) to maintain a coolable geometry.
Question 1 EPRI Report 3002028674/5 was submitted concurrently with the review of WCAP-18850, which is the base methodology supporting EPRI Report 3002028674/5. Any changes to WCAP-18850 that have occurred during the course of the NRC's review must be considered for any impacts to EPRI Report 3002028674/5. Specifically, the NRC is requesting that the following be reviewed:
- a. Any methodology changes to WCAP-18850 that affect the LOCA evaluations included in EPRI Report 3002028674/5.
- b. Any substantive differences between the proposed limitations and conditions in the as-submitted version of WCAP-18850 and the final limitations and conditions of WCAP-18850.
For any items identified to be within the scope of (a) or (b) please provide justification that the existing LOCA evaluations included in EPRI Report 3002028674/5 remain applicable or provide new LOCA evaluations including the changes to the methodology or limitations and conditions.
2 OFFICE NRR/DORL/LLPB/PM NRR/DORL/LLPB/BC NRR/DSS/SFNB/BC NAME JDelosreyes JRankin SKrepel DATE 07/09/2025 07/09/2025 06/06/2025