ML060730382
| ML060730382 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 03/14/2006 |
| From: | Harden P Nuclear Management Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML060730382 (3) | |
Text
Palisades Nuclear Plant Operated by Nuclear Management Company, LLC March 14,2006 10 CFR 50.46 U. S. Nudear Regulatory Commission AlTN: Document Control Desk Washington, DC 20555-0001 Palisades Nuclear Plant Docket 50-255 License No. DPR-20 Report of Chanaes in Ememencv Core Coolina System Models Nuclear Management Company, LLC (NMC), is submitting a 30-day report of changes in the emergency core cooling system (ECCS) modets for the Palisades Nuclear Plant (PNP). The report is submitted in accordance with 10 CFR 50.46(a)(3)(ii) as a significant change in peak cladding temperature (PCT) of greater than 50' F.
NMC identified a potential issue with thecontainment heat structures in the Final Safety Analysis Report (FSAR) Appendix K large break loss of coolant accident (LBLOCA) analysis for PNP (FANP CR 20054791). NMC provided new containment heat structure data to Framatome-ANP (FANP) and requested an analysis of the impact on
- PCT, White performing the analysis for the impact on PCT, FANP found conservative errors in the ICECON input for the Palisades Appendix K LBLOCA analysis of record (FANP CR 2006-585). The original 1975 development of the model overstated the thickness of some containment heat structures.
The PCT impact of these two errors is included in the enclosure. Note that the two errors identified have removed excessive consenratisms in the containment heat sinks used in the LOCA mass and energy calculation, and have resulted in a reduction in the PCT. A reanalysis is not considered to be necessary since the identified errors will result in a significant benefit, and more than compensate for the PCT penalties identified in previous 10 CFR 50.46 reports, as summarized in the enclosure.
27780 Blue Star Memorial Highway rn Covert, Michigan 49043-9530 Telephone: 269.764.2000
Document Control Desk Page 2 There remains over 250' F of margin to the PCT limit of 2200 F; therefore. PMP continues to meet all 10 CFR 50.46 requirements, and does not intend to perform a reanalysis to incorporate these identified errors.
Summaw of Commitments This letter contains no new commitments and no revisions to existing commitments.
Paul A. Harden Site Vice President, Palisades Nuclear Plant Nuclear Management Company, LLC Enclosure CC Administrator, Region 111, USNRC Project Manager, Palisades, USNRC Resident Inspector, Palisades, USNRC
ENCLOSURE LARGE BREAK LOSS OF COOLANT ACCIDENT PEAK CLADDING TEMPERATURE
SUMMARY
Page 1 of 1 PCT (Last Acceptable M ode1 Results) 10 CFR 50.46 Changes CR 9266 Error In Break Loop SG Exit Junction Inertia CR 9429 Error In Fast Flux Input To RODEX2 PCT (2001 Annual Report) 10 CFR 50.46 Changes CR 9156 Error In TOODEE2 Clad Thermal Expansion CR 8674 RFPAC V&V Findings From CDUP PCT (2002 Annual Report)
PCT (2003 Annual Report)
PCT (2004 Annual Report)
PCT (2005 Annual Report) 10 CFR 50.46 Changes CR 2005-4791 Large Break LOCA Containment Heat Sink Modeling Inputs CR 2006-585 Incorrect ICECON Heat Structure Input for Palisades Appendix K LBLOCA APCT ("F)
+I
+4
-1
+28
-5 4 1 FCT (OF) 1929 4934 1961 1961 1961 1961 1956 1915