ML102240453

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Draft Request for Additional Information LAR on Fuel Assembly Movement
ML102240453
Person / Time
Site: San Onofre  Southern California Edison icon.png
Issue date: 08/11/2010
From: Hall J
Plant Licensing Branch IV
To: Conklin L
Southern California Edison Co
Hall, J R, NRR/DORL/LPL4,301-415-4032
Shared Package
ML102240452 List:
References
TAC ME3136, TAC ME3137
Download: ML102240453 (1)


Text

DRAFT REQUEST FOR ADDITIONAL INFORMATION REGARDING MOVEMENT OF FUEL ASSEMBLIES TECHNICAL SPECIFICATION CHANGE SAN ONOFRE NUCLEAR GENERATING STATION, UNITS 2 AND 3 (TAC NOS. ME3136 and ME3137)

The Nuclear Regulatory Commission (NRC) staff has determined that additional information is needed to complete its review of the subject license amendment request (LAR) for San Onofre Nuclear Generating Station (SONGS), Units 2 and 3, sent by application dated January 14, 2010, (ML100210200) from Southern California Edison (SCE or the licensee). The following question constitutes our request for additional information.

1. In Section 3.2, Discussion of the LAR the licensee states, A new analysis, "Updated SONGS 2 & 3 Fuel Assembly Drop Analysis of Record" (AOR) (Reference 2) was performed and has subsequently replaced the Fuel Bundle Drop Fuel Rod Failure Evaluation for SCE Units 2 & 3 (Reference 1).

For fuel bundle drop scenarios in the fuel storage pool and core locations, the results of the updated analysis demonstrate that the maximum total number of fuel rods predicted to fail in the dropped and impacted fuel bundles is a total of 472 rods (this represents all fuel rods in both assemblies).

The control room and offsite dose consequences of 472 rods being failed were evaluated and determined to meet the 10 CFR 50.59 minimal dose increase criterion as defined in Regulatory Guide 1.187.

Based on the above statement, the licensee currently has a new fuel assembly drop analysis of record (AOR) that uses heavier bundle weights, and includes the weights of components, handling grapples, and a discretionary margin of 50 pounds, which have not been accounted for in previous fuel assembly drop analyses.

Although the new AOR was performed in accordance with Title 10 of the Code of Federal Regulation (10 CFR) 50.59, the evaluation provides the basis supporting the proposed technical specification changes. As such, the NRC staff cannot adequately evaluate the impact of the proposed changes without conducting a review of the analysis and results. Therefore, please submit the applicable new AOR and/or the corresponding 10 CFR 50.59 evaluation, in order for NRC staff to evaluate the impact of the changes on the control room and offsite doses associated with the fuel handling accident.

If providing the new AOR, please explain how the change impacts the frequency of occurrence of the fuel handling accident previously evaluated. Also, please explain how the change impacts the fuel handling accident previously evaluated.

Enclosure