NRC 2011-0050, Emergency Core Cooling System Evaluation Model Changes
| ML111260218 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 05/05/2011 |
| From: | Jim Costedio Point Beach |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| NRC 2011-0050 | |
| Download: ML111260218 (4) | |
Text
May 5,201 1 POINT BEACH NRC 201 1-0050 10 CFR 5OS46(a)(3)(ii)
U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 Point Beach Nuclear Plant, Units 1 and 2 Dockets 50-266 and 50-301 Renewed License Nos. DPR-24 and DPR-27 Emergencv Core Coolincl Svstem Evaluation Model Changes In accordance with 10 CFR 50.46(a)(3)(ii), NextEra Energy Point Beach (NextEra), LLC, is submitting this annual report of changes to, and errors discovered in, emergency core cooling system (ECCS) evaluation models for Point Beach Nuclear Plant (PBNP), Units 1 and 2. This letter provides a summary of the ECCS evaluation model changes and errors identified since the previous annual report dated June 21, 201 0. describes the ECCS evaluation model changes and errors for the large and small break loss of coolant accident (LOCA). Enclosure 2 provides the large break LOCA margin summary sheet for 2010. Enclosure 3 provides the small break LOCA margin summary sheet for 201 0.
There were no changes or errors to the large break or small break LOCA evaluation models during this reporting period that resulted in a change to the calculated peak clad temperature.
This submittal contains no new commitments or revisions to existing commitments.
Very truly yours, NextEra Energy Point Beach, LLC James Costedio Licensing Manager Point Beach Nuclear Plant Enclosures cc:
Administrator, Region Ill, USNRC Project Manager, Point Beach Nuclear Plant, USNRC Resident Inspector, Point Beach Nuclear Plant, USNRC NextEra Energy Point Beach, LLC, 6610 Nuclear Road, Two Rivers, WI 54241
ENCLOSURE I NEXTERA ENERGY POINT BEACH, LLC POINT BEACH NUCLEAR PLANT, UNITS I AND 2 ECCS EVALUATION MODEL CHANGES AND ERRORS
References:
,(I)
NextEra Energy Point Beach, LLC letter to NRC, dated June 21, 201 0, ECCS Evaluation Model Changes (MLI 01 740064)
(2)
NRC letter to NextEra Energy Point Beach, LLC, dated October 29,2009, Issuance of Amendment Re: Use of ASTRUM for LBLOCA (ML092931684)
This is the annual report of changes to, and errors discovered in, emergency core cooling system (ECCS) evaluation models for Point Beach Nuclear Plant (PBNP) Units 1 and 2, for 2010. The report provides a summary of ECCS evaluation model changes and errors identified since the previous annual report dated June 21, 2010 (Reference 1). Westinghouse Electric Company is the analysis of record holder for the large break and small break loss of coolant accident (LOCA) analyses for PBNP. The large break LOCA analysis is performed using the 2004 Westinghouse Realistic Large Break LOCA Evaluation Model using ASTRUM. The small break LOCA analysis is performed using the 1985 Westinghouse Small Break LOCA Evaluation Model with NOTRUMP.
LARGE BREAK LOCA ECCS EVALUATION MODEL CHANGES AND ERRORS The large break LOCA analysis was reanalyzed using the 2004 Westinghouse Realistic Large Break LOCA Evaluation Model using ASTRUM, as approved by the NRC via Amendments 235 and 239 to DPR-24 and DPR-27, respectively dated October 29, 2009 (Reference 2). There were no changes or errors in the new analysis during this reporting period that resulted in a change to the calculated peak clad temperature (PCT). Enclosure 2 provides a summary of PCT changes for Units I and 2.
SMALL BREAK LOCA ECCS EVALUATION MODEL CHANGES AND ERRORS There were no changes or errors to the small break LOCA evaluation model during this reporting period that resulted in a change to the calculated PCT for PBNP. Enclosure 3 provides a summary of PCT changes for PBNP Units 1 and 2.
Page 1 of 1
ENCLOSURE 2 NEXTERA ENERGY POINT BEACH, LLC POINT BEACH NUCLEAR PLANT, UNITS I AND 2 LARGE BREAK LOCA MARGIN
SUMMARY
SHEET FOR 2010 Evaluation Model:
2004 Westinghouse Realistic Large Break LOCA Evaluation Model using ASTRUM.
Evaluation Model PCT (Unit 1IUnit 2):
1975°F/18100F Net PCT Effect Absolute PCT Effect Unit l/Unit 2 Unit IIUnit 2 Prior 10 CFR 50.46 Changes or A
Error Corrections - up to Year 2009 APCT Prior 10 CFR 50.46 Changes or Errors Corrections - Year 201 0 APCT O"F/O°F 10 CFR 50.46 Changes in Year 2010 Since Item B Absolute Sum of 10 CFR 50.46 Changes None APCT O°F/OOF None The sum of the PCT from the most recent analysis using an acceptable evaluation model and the estimates of PCT impact for changes and errors identified since this 1975°F/1810"F < 2200°F analysis Page 1 of 1
ENCLOSURE 3 NEXTERA ENERGY POINT BEACH, LLC POINT BEACH NUCLEAR PLANT, UNITS I AND 2 SMALL BREAK LOCA MARGIN
SUMMARY
SHEET FOR 2010 Evaluation Model:
1985 Westinghouse Small Break LOCA Evaluation Model with NOTRUMP Evaluation Model PCT (Unit 1IUnit 2):
1 157"F/I 046°F Net PCT Effect Absolute PCT Effect Unit 11Unit 2 Unit 1IUnit 2 Prior 10 CFR 50.46 Changes or A
Error Corrections - up to Year 2009 APCT
+48"F/+48"F
+48"F/+48"F Prior 10 CFR 50.46 Changes or Errors Corrections - Year 201 0 10 CFR 50.46 Changes in Year 2010 Since Item B Absolute Sum of 10 CFR 50.46 Changes APCT None APCT None The sum of the PCT from the most recent analysis using an acceptable evaluation model and the estimates of PCT impact for changes and errors identified since this 1205"F/1094"F < 2200 OF analysis Page 1 of 1