ML13087A574
| ML13087A574 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf  |
| Issue date: | 03/28/2013 |
| From: | Wang A Plant Licensing Branch IV |
| To: | Davant G Entergy Operations |
| Wang A | |
| References | |
| TAC ME9873 | |
| Download: ML13087A574 (2) | |
Text
From:
Wang, Alan To:
"DAVANT, GUY H" Cc:
Lent, Susan; Burkhardt, Janet; Ward, Steven; SEITER, JEFFERY ALAN
Subject:
Grand Gulf Nuclear Station Request for Additional Information Regarding Final Feedwater Temperature Reduction (FFWTR) license amendment request (ME9873)
Date:
Thursday, March 28, 2013 11:38:47 AM
- Guy, By letter dated October 26, 2012 (Agencywide Documents Access management System (ADAMS) Accession number ML123060613), Entergy Operations, Inc. (the licensee),
requested an amendment to Facility Operating License Number NPF-29 for Grand Gulf Nuclear Station, Unit 1 (GGNS). The license amendment request (LAR) proposes to delete Section 2.C.(32) of the GGNS Operating License, which currently prohibits operating with partial feedwater heating for the purpose of extending the fuel cycle.
The NRC staff has determined that additional information is needed to complete our review of this request. The following request for additional information (RAIs) are related to your LAR dated October 26,2012:
- 1) In the first paragraph of Section 2.1 (page 9) of Attachment 2 (Reference 1) to the LAR, it was stated that the effect of the 100°F FWHOOS condition on the ECCS performance for the limiting break failure combination was previously evaluated for the GGNS Extended Power Uprate using the NRC-approved SAFER/GESTR-LOCA methodology, and that the results of this evaluation are also applicable to a 100°F FFWTR.
Please provide the following additional information:
a) Clarify, whether the only difference between the analyses for 100°F FWHOOS and 100°F FFWTR cases are the core exposure levels assumed in the two cases, because FWHOOS event is expected to occur before End-of-Cycle (EOC) and FFWTR after EOC. And if so, b) Provide the core exposure levels assumed in the 100°F FWHOOS and the FFWTR analyses, and corresponding values for MAPLHGR and PCT for the two cases.
c) If the difference between the two cases involves more than just the core exposure level, then discuss those differences and their effects on the safety analysis results.
- 2) Provide the exposure-dependent MAPLHGR limit curve showing in the curve the higher exposure level that will be achieved for FFWTR operation and the exposure at which the limiting PCT (i.e., the current licensing-basis PCT of 1,690°F) occurs.
- 3) In Section 6.1 of Attachment 2 (page 24) of the LAR, it was stated, Any effects of a slightly higher core exposure with FFWTR on the AOO performance is addressed as part of the cycle-specific reload analysis.
Clarify, for which operating cycles (the current cycle and/or the future cycles) the licensee is planning to operate with FFWTR. If it includes the current operating cycle, then provide the cycle-specific reload analysis report that should have been specifically performed for the current cycle with FFWTR, and discuss any effects of a slightly higher core exposure on the plant safety analyses, including thermal-hydraulic stability analysis.
References
- 1. GEH Report NEDC-33671P, Safety Analysis Report for Operation with Final Feedwater Temperature Reduction at Grand Gulf Nuclear Station, Rev. 0, October 2012.
This RAI was discussed with Mr. Guy Davant of on March 28, 2013, and it was agreed that a response would be provided within 60 days of receipt of this email. If circumstances result in the need to revise the requested response date, please contact me at (301) 415-1445 or via e-mail at Alan.Wang@nrc.gov.
Alan Wang Project Manager (Grand Gulf Nuclear Station)
Nuclear Regulatory Commission Division of Operating Reactor Licensing Alan.Wang@NRC.gov Tel: (301) 415-1445 Fax: (301) 415-1222