LR-N04-0337, Loss of Coolant Accident Peak Clad Temperature Annual Report

Loss of Coolant Accident Peak Clad Temperature Annual Report

ML042230290
Person / Time
Site:	Salem
Issue date:	07/29/2004
From:	Mannon S Public Service Enterprise Group
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LR-N04-0337
Download: ML042230290 (4)

Text

PSEG Nuclear LLC P.O. Box 236, Hancocks Bridge, New Jersey 08038-0236 JUL 2 9 2004 0 PSEG LR-N04-0337 NuclearLLC United States Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 SALEM LOSS OF COOLANT ACCIDENT PEAK CLAD TEMPERATURE ANNUAL REPORT SALEM GENERATING STATION, UNIT NOS. I AND 2 FACILITY OPERATING LICENSE DPR-70 AND DPR-75 DOCKET NOS. 50-272 AND 50-311 Under IOCFR50.46, PSEG Nuclear is required to submit an annual report to the NRC identifying the status of the peak clad temperatures predicted by the Large Break (LB) and Small Break (SB) Loss of Coolant Accident (LOCA) evaluation models for Salem.

The last Peak Clad Temperature (PCT) report PSEG Nuclear filed with the NRC for Salem was dated August 08, 2003 (LRN-03-0333).

In our last report to the NRC, the following LOCA peak clad temperatures (PCTs) were identified.

Si LB LOCA-PCTast report = 20830F S1 SB LOCA-PCTjast report = 16890F S2 LB LOCA-PCTiastreport = 20830F S2 SB LOCA-PCTiast report = 16890F Two additional penalties have been identified and one planned plant change impacting the PCT has been implemented since our last report. These changes have not yet been reported to the NRC. The change to the PCT as a result of the penalties and planned plant change are discussed below.

.AoD' 95-2168 REV. 7/99

Document Contlol Desk 2 UUL 2 9 2804 LR-N04-0337

1. NOTRUMP Bubble Rise I Drift Flux Model Inconsistency Corrections Small Break LOCA-PCT NOTRUMP was updated to resolve some inconsistencies in several drift flux models as-well as the nodal bubble rise I droplet fall models. These changes include: bubble rise and droplet fall model calculations were made consistent with flow link calculations.

Corrections were made to limits employed in the vertical counter-current flooding models. Checking logic was added to correct situations where drift flux model inconsistencies could result. Also, a more rigorous version of the Yeh Drift Flux Model was implemented since the previous version of this model was incorrectly restricted to a 50% void fraction limit. The implementation of these corrections leads to a bounding 350 F increase in the calculated PCT. Per standard Westinghouse evaluation methodology, an additional 50F penalty was assessed to account for "burst and blockage" and 'time in life" issues that result due to the SB-LOCA PCT exceeding 1700 0F. Thus, the total penalty assessed for the Small Break LOCA-PCT for both Salem Units 1 and 2 is +400F. A "30-Day Report" to the NRC was not required since this penalty resulted in a change in PCT of less than 500F.

2. Removal of "Transition Core Penalty" for Salem Unit 2 Large Break LOCA-PCT Both Salem Units have previously been assessed a +500F 'Transition Core Penalty" as a result of a mixed core of V5H and RFA fuel types. Salem Unit 2 Cycle 14, which began operation in November 2003, now contains all RFA fuel. Thus, this planned plant change implemented via the 50.59 process allows the removal of the previously assessed +500F "Transition Core Penalty" for Salem Unit 2. A '30-Day Report" to the NRC was not required since changes to the PCT resulting from planned plant changes implemented under the 50.59 process do not count towards the 500F threshold per WCAP-13451. Note that Salem Unit 1 continues to operate with a mixed core, hence the 'Transition Core Penalty" remains applicable to Salem Unit 1.

3. LOCBART Fluid Property Logic Correction of Discrepancies Large Break LOCA-PCT Several minor discrepancies related to the LOCBART fluid property logic were discovered and corrected, resulting in an assessment of +50F for the Large Break LOCA-PCT.

Document Control Desk 3 'JUL 2 9 0 LR-N04-0337 Thus, the current LOCA-PCT for Salem Units 1 and 2 Is summarized below. The SB and LB LOCA analyses for both units still remain within the criteria set forth In 10 CFR 50.46.

Si LB LOCA-PCTcurrent = 20880 F (20830 F + 5-F)

Si SB LOCA-PCTcurnnt = 17291F (1689 0 F + 40 0F)

S2 LB LOCA-PCTcurrent = 2038°F (20830 F - 500 F + 50F)

S2 SB LOCA-PCTurmnt = 17290 F (1689OF + 400F)

Should you have any questions regarding this report, please contact Michael Mosier at (856) 339-5434.

Sincerely, Steven R. Mannon Manager Nuclear Safety and Licensing

Document Control Desk 4 'UL 2 9 2004 LR-N04-0337 C Regional Administrator - NRC Region I U. S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Mr. D. Collins, Project Manager - Salem U.S. Nuclear Regulatory Commission Mail Stop 08C2 Washington, DC 20555-0001 USNRC Senior Resident Inspector - Salem (X24)

Mr. K. Tosch, Manager IV Bureau of Nuclear Engineering P.O. Box 415 Trenton, NJ 08625