ML121740051

List of Questions for Supplement to Complete Acceptance Review, License Amendment Request to Adopt NFPA-805 Performance-Based Standard for Fire Protection for LWR Electric Generating Plants

ML121740051
Person / Time
Site:	Cooper
Issue date:	06/21/2012
From:	Lynnea Wilkins Plant Licensing Branch IV
To:	Mccutchen E Nebraska Public Power District (NPPD)
Wilkins, L E, NRR/DORL/LPL4, 415-1377
Shared Package
ML121740044	List: ML121740047 ML121740051
References
TAC ME8551
Download: ML121740051 (1)

Text

1. LAR, Attachment G states that a majority of recovery actions (RA) currently credited have been assessed under the existing Fire Protection Program, which included field validation. However, according to LAR Attachment S, Implementation Item S-3.6, a confirmatory demonstration (field validation walk-through) of the feasibility for the credited NFPA 805 recovery actions will be performed and documented as part of LAR implementation. It appears that the extent to which the RA feasibility evaluation remains to be completed. Please provide the results of the completed evaluation and clarify the potential impact this remaining work may have on the results presented in the LAR.

2. The additional risk of recovery actions is reported in LAR Table W-2 to be negative in several fire areas. This appears to be due to combining the risk reductions from plant modifications with the additional risk of recovery actions in the going forward plant, but not in the baseline (compliant) plant. To correct the calculation of the additional risk of recovery actions, plant modifications must be credited in the going forward plant as well as the baseline; in other words, the only difference in the going forward plant PRA and the baseline PRA is the credit for recovery actions. Please provide corrected results for the additional credit for recovery actions identified in Table W-2 on a fire area basis.

3. LAR section V.2 identifies deviations from the guidance in NUREG/CR-6850. For Transient Fire Frequency, influence factors less than one were used. Also, a factor of 0.1 was used to modify both fire frequency from transients (bins 7, 25, and 37) and transient fires caused by welding and cutting (bins 6, 24, and 36) for certain fire zones.

Please provide a simultaneous or composite sensitivity analysis of the impact on CDF, LERF, CDF, and LERF using NUREG/CR-6850 methods. It is expected that, concurrently, the credit for the factor of 0.1 which modifies the fire frequency would be removed, i.e. 1 would replace the 0.1, and that influence factors less than 1 would be replaced by those integers documented in Table 6-3 of NUREG/CR-6850.

4. LAR Attachment U uses the term vendor and utility when describing the makeup of the team that performed the R.G. 1.200 Rev 1 peer review of the internal events PRA. This is confusing terminology potentially implying that the review was not an independent peer review as defined in the ASME/ANS PRA Standard. Provide clarification that the peer review of the internal events PRA discussed in Attachment U met the requirements of Sections 1-6 and 2-3 of the ASME/ANS PRA Standard for a peer review. If not provide the F&Os and resolutions from the most recent full-scope peer review.