ML14058A044

Email from S. Weerakkody, NRR to F. Ferrante, NRR OUO SRI - in Dam Failure Frequency

ML14058A044
Person / Time
Site:	Oconee
Issue date:	10/17/2011
From:	Sunil Weerakkody Office of Nuclear Reactor Regulation
To:	Ferrante F Office of Nuclear Reactor Regulation
Shared Package
ML14055A421	List: ML090570117 ML090680737 ML091620669 ML092020480 ML092940769 ML100280954 ML101750619 ML101890803 ML102990064 ML103410042 ML12268A404 ML14055A410 ML14055A411 ML14055A474 ML14058A015 ML14058A016 ML14058A017 ML14058A018 ML14058A019 ML14058A020 ML14058A021 ML14058A022 ML14058A023 ML14058A024 ML14058A025 ML14058A026 ML14058A027 ML14058A028 ML14058A029 ML14058A030 ML14058A031 ML14058A032 ML14058A033 ML14058A034 ML14058A035 ML14058A036 ML14058A037 ML14058A038 ML14058A039 ML14058A040 ML14058A042 ML14058A043 ML14058A044 ML14058A045 ML14058A046 ML14058A047 ML14058A048 ML14058A049 ML14058A050 ML14058A051 ... further results
References
FOIA/PA-2012-0325
Download: ML14058A044 (2)

Text

Ferrante, Fernando From: Weerakkody, Sunil (/ '*--*

Sent: Monday, October 17, 2011 11:47 AM To: Ferrante, Fernando

Subject:

RE: OUO SRI - RE: IN Dam Failure Frequency -- SUNSI Review - OUO-SRI Nice! Thank you.

Sunil From: Ferrante, Fernando \ "

Sent: Monday, October 17, 2011 11:41 AM To: Beaulieu, David Cc: Rosenberg, Stacey; Weerakkody, Sunil

Subject:

OUO SRI - RE: IN Dam Failure Frequency -- SUNSI Review - OUO-SRI

Dave, I have been closely following the issue with OUO-SRI with respect to GI-204 and based on my understanding of how RES resolved this issue with NSIR and the current content of their screening report, I can confirm the correctness of my original Form 665S SUNSI review determination.

This is based on the fact that (i) there is no discussion in the IN with respect to specific impacts to an NPP site as described in the redacted paragraph for the screening report, and (ii) discussion of Jocassee Dam/ONS and failure rates for dams (the core of the discussions in the IN) are also contained in the screening report. The GSI screening report, in fact, goes beyond information in the IN and explicitly refers to dam failure rates included in non-public NRC internal analysis, which the IN does not mention. Hence, I believe the IN is more conservative with respect to the guidance provided by NSIR, but appropriate for the context of the IN. Last, but not least, the content of the IN has been briefed to DRA management and in LT/ET meetings and the recommendation has always been to issue the IN publicly. I believe the effort undertaken by RES with NSIR regarding the screening report actually reinforces the decision to publicly release the IN.

Thank you, Fernando From: Beaulieu, David Sent: Monday, October 17, 2D11 9:51 AM To; Ferrante, Fernando Cc: Rosenberg, Stacey

Subject:

IN Dam Failure Frequency -- SUNSI Review As you know, because the IN and GSI must made publicly available together at the same time, the final signature of the IN has been delayed because NRR concurrence on the GSI had delayed to resolve whether the GSI contains OUO-Security Related Information. I spoke with Richard Perkins last week who said that it is his understanding that NRR intended resolve OUO-SRI concern by blacking out the below paragraph from the public version of the GSI making the entire GSI uncontrolled. I reviewed the latest version of the IN (attached) and found no similar plant-specific details. Fernando, please review the IN in light of this new information and confirm the correctness of your Form 665S SUNS[ review where you specified a document availability of Publicly Available, Non-Sensitive.

Notification from Jocassee would occur before a total failure of the dam; however, for purposes of this timeline, notification is assumed to be at the same time the dam fails.

Following notification from Jocassee, the reactor(s) are shutdown within approximately 1

hour. The predicted flood would reach [Oconee Nuclear Station] in approximately 5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />, at which time the [Standby Shutdown Facility] walls are overtopped. The

[Standby Shutdown Facility] is assumed to fail, with no time delay, following the flood level exceeding the height of the [Standby Shutdown Facility] wall. The failure scenario results are predicted such that core damage occurs in about 8 to 9 hours1.041667e-4 days <br />0.0025 hours <br />1.488095e-5 weeks <br />3.4245e-6 months <br /> following the dam break and containment failure in about 59 to 68 hours7.87037e-4 days <br />0.0189 hours <br />1.124339e-4 weeks <br />2.5874e-5 months <br />. When containment failure occurs, significant dose to the public would result.

AVID BEAULIEU PROJECT MANAGER NRR/OPR/PGCB (bwl-yer) 301-415-3243 I 012H17 I David.Beaulieu@nrc.gov U.S. Nuclear Regulatory Commission 2