ML043650354

2003 Emergency Core Cooling System Annual 10 CFR 50.46 Report, San Onofre Nuclear Generating Station, Units 2 and 3

ML043650354
Person / Time
Site:	San Onofre
Issue date:	12/23/2004
From:	Scherer A Southern California Edison Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
CENPD-279 Suppl 15
Download: ML043650354 (20)

Text

IiXISOUTHERN CALIFORNIA A. Edward Scherer EDISON Manager of Nuclear Regulatory Affairs An EDISON IXTERNATIONVALe Company December 23, 2004 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D. C. 20555

Subject:

Docket Nos. 50-361 and 50-362, 2003 Emergency Core Cooling System Annual 10 CFR 50.46 Report, San Onofre Nuclear Generating Station, Units 2 and 3.

References:

1. Letter from A. E. Scherer (SCE) to Document Control Desk (NRC), dated December 15, 2003,

Subject:

Docket Nos. 50-361 and 50-362, 2002 Emergency Core Cooling System Annual 10 CFR 50.46 Report, San Onofre Nuclear Generating Station, Units 2 and 3

2. CENPD-279, Supplement 15, "Annual Report on Combustion Engineering ECCS Performance Evaluation Models for PWRs,"

March 2004 Gentlemen:

This letter transmits as Enclosures 1 and 2 the San Onofre Units 2 and 3 annual report for the 2003 calendar year required by paragraph (a)(3)(ii) of 10 CFR 50.46, "Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors." This regulation requires Southern California Edison (SCE) to annually report to the NRC for San Onofre Units 2 and 3 the nature of each change to or error discovered in the Emergency Core Cooling System (ECCS) evaluation model or in the application of this model that affects the temperature calculation and estimated effects of any such changes, errors, or applications on the limiting ECCS analysis. Any significant change or error is required to be reported to the NRC within 30 days.

The previous Emergency Core Cooling System Annual 10 CFR 50.46 Report was submitted to the NRC in Reference 1.

Reference 2 (included as Enclosure 1) describes the codes and methodology used by Westinghouse Electric Company for the San Onofre Units 2 and 3 ECCS analyses for this reporting period. Reference 2, Appendix C summarizes the plant specific evaluation for San Onofre Units 2 and 3. Appendices A, B, D, E, F, and G of Reference 2 apply to plants other than San Onofre, and therefore, are not included.

P.O. Box 128 San Clemente, CA 92674-0128 949-368-7501 N

Fax 949-368-7575

Document Control Desk December 23, 2004 Reference 2, Appendix C describes a plant-specific issue concerning suction leg elevation. This issue had no effect on Peak Cladding Temperature (PCT) for the Large Break Loss of Coolant Accident (LBLOCA) and a 30F effect on the Small Break Loss of Coolant Accident (SBLOCA). This item was previously reported by SCE to the NRC in Reference 1.

SCE made no changes to the LOCA evaluation models. provides a summary of the effect on PCT of the errors or changes to the ECCS evaluation model reported under 10 CFR 50.46 for this reporting period. While not limiting with regard to PCT, detailed information for the Small Break LOCA is also included in Enclosure 2 (in accordance with Supplement 1 to Information Notice 97-15).

Operating Cycle Information Unit 2 and Unit 3 operation for the current reporting period is outlined below.

I Unit Year I Cycle 11 Cycle I January 1, 2003 2 2003 N/A through December 31, 2003 January 1, 2003 February 16, 2003 3 2003 To through January 6, 2003 December 31, 2003 SONGS Units 2 and 3 Larae Break LOCA Evaluation Model - 2003 Reporting Period The Large Break LOCA analysis uses the evaluation model approved on June 1985. The limiting Large Break LOCA PCT did not exceed the 10 CFR 50.46(b)(1) acceptance criterion of 2,200 OF. This is documented in Table 1 (Enclosure 2).

The cumulative (sum of the absolute magnitudes of PCT changes) Large Break LOCA "10 CFR 50.46 model changes and model errors, since the approval of the "June 1985 Evaluation Model," remains less than 1 0F. This is documented in Table 2 (Enclosure 2).

Document Control Desk December 23, 2004 SONGS Units 2 and 3 Small Break LOCA Evaluation Model - 2003 Reporting Period The Small Break LOCA analysis uses the Supplement 2 Model (S2M) SBLOCA evaluation model approved on February 22, 2000. The limiting Small Break LOCA PCT did not exceed the 10 CFR50.46(b)(1) acceptance criterion of 2,200 OF, and remained bounded by the large break LOCA PCT. This is documented in Table 3 (Enclosure 2).

The cumulative (sum of the absolute magnitudes of PCT changes) Small Break LOCA 10 CFR50.46 model changes and model errors, since the approval of the US2M Evaluation Model", is 19 "F. This is documented in Table 4 (Enclosure 2).

An authorization for the NRC to reproduce the copyrighted Reference 2 is provided in in the "Copyright Notice" Section.

If you have any questions or need additional information on this subject, please contact Mr. J. L. Rainsberry at 949/368-7420.

Sincerely, cc: B. S. Mallett, Regional Administrator, NRC Region IV B. M. Pham, NRC Project Manager, San Onofre Units 2 and 3 C. C. Osterholtz, NRC Senior Resident Inspector, San Onofre Units 2 and 3

Enclosure 1 (12 pages including this page)

Westinghouse Non-Proprietary Class 3 CENPD-279, Supplement 15 March 2004 Annual Report on Combustion Engineering ECCS Performance Evaluation Models for PWRs S Westinghouse

CENPD -279, Supp. 15 LEGAL NOTICE This report was prepared as an account of work performed by Westinghouse Electric Company LLC. Neither Westinghouse Electric Company LLC nor any person acting on its behalf:

A. Makes any warranty or representation, express or implied including the warranties of fitness for a particular purpose or merchantability, with respect to the accuracy, completeness, or usefulness of the information contained in this report, or that the use of any information, apparatus, method, or process disclosed in this report may not infringe privately owned rights; or B. Assumes any liabilities with respect to the use of, or for damages resulting from the use of, any information, apparatus, method or process disclosed in this report.

COPYRIGHT NOTICE This report has been prepared by Westinghouse Electric Company LLC (WEC) and bears a Westinghouse Electric Company LLC copyright notice. Information in this report is the property of and contains copyright information owned by NNXEC and/or its subcontractors and suppliers. It is transmitted to you in confidence and trust, and you agree to treat this document and the information contained therein in strict accordance with the terms and conditions of the agreement under which it was provided to you.

You are permitted to make the number of copies of the information contained in this report which are necessary for your internal use in connection with your implementation of the report results for your plant(s) in your normal conduct of business. Should implementation of this report involve a third party, you are permitted to make the number of copies of the information contained in this report which are necessary for the third party's use in supporting your implementation at your plant(s) in your normal conduct of business if you have received the prior, written consent of WEC to transmit this information to a third party or parties. All copies made by you must include the copyright notice in all instances and the proprietary notice if the original was identified as proprietary.

The NRC is permitted to make the number of copies beyond those necessary for its internal use that are necessary in order to have one copy available for public viewing in the appropriate docket files in the NRC public document room in Washington, DC if the number of copies submitted is insufficient for this purpose, subject to the applicable federal regulations regarding restrictions on public disclosure to the extent such information has been identified as proprietary.

Copies made by the NRC must include the copyright notice in all instances and the proprietary notice if the original was identified as proprietary.

© Copyright 2004, Westinghouse Electric Company LLC. All rights reserved.

CENPD -279, Supp. 15 ABSTRACT This report describes changes and errors in the ECCS perfornance evaluation models (EM) for PWk'Rs developed by Combustion Engineering in calendar year (CY) 2003 per the rcquirements of IOCFR50.46. For this reporting period, there were no changes or errors in the evaluation models or application of the models that affect the cladding temperature calculation.

The sum of the absolute magnitude of the generic peak cladding temperature (PCT) changes for the large break LOCA June 1985 EM from all reports to date continues to be less than I F excluding plant specific effects. The generic impact on the peak cladding temperature for the large break LOCA 1999 ENI is less than 1.20 F. The generic sum of the absolute magnitude of the peak cladding temperature changes for the small break LOCA S IM evaluation model from all reports to date is less than 3Cr. There is no generic accumulated change in peak cladding temperature for the small break LOCA S2M\l evaluation model. No change occurred in the PCT due to post-LOCA long term cooling issues. The total effect relative to the 50OF definition of a significant change in PCT for each evaluation model is the sum of the generic effects for that model and plant specific effects, if any, described in Appendices A-G.

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CENPD -279, Supp. 15 TABLE OF CONTENTS Section Title Pme

1.0 INTRODUCTION

1 2.0 COMBUSTION ENGINEERING ECCS EVALUATION MODELS AND CODES 3 3.0 EVALUATION MODEL CHANGES AND ERROR CORRECTIONS 4

4.0 CONCLUSION

S 6

5.0 REFERENCES

7 APPENDICES (Plant Specific Considerations)

A. ARIZONA PUBLIC SERVICE COMPANY (PVNGS Units 1-3)

B. CALVERT CLIFFS NUCLEAR POWER PLANT INCORPORATED (Calvert Cliffs Units I & 2)

C. SOUTHERN CALIFORNIA EDISON COMPANY (SONGS Units 2 & 3)

D. DOMINION RESOURCES (Millstone Unit 2)

E. ENTERGY OPERATIONS, INCORPORATED I. Arkansas Nuclear One Unit 2

2. Waterford Unit 3 F. FLORIDA POWER AND LIGHT COMPANY (St. Lucie Unit 2)

G. CONSUMERS ENERGY COMPANY (Palisades)

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CENPD -279, Supp. 15

1.0 INTRODUCTION

This report addresses the NRC requirement to report changes or errors in ECCS performance evaluation models. The ECCS Acceptance Criteria, Reference 1, spell out reporting requirements and actions required when errors are corrected or changes are made in an evaluation model or in the application of a model for an operating licensee or construction permittee of a nuclear power plant.

The action requirements in IOCFR50.46(a)(3) are:

1. Each applicant for or holder of an operating license or construction permit shall estimate the effect of any change to or error in an acceptable evaluation model or in the application of such a model to determine if the change or error is significant. For this purpose, a significant change or error is one which results in a calculated peak fuel cladding temperature (PCT) different by more than 50'F from the temperature calculated for the limiting transient using the last acceptable model, or is a cumulation of changes and errors such that the sum of the absolute magnitudes of the respective temperature changes is greater than 50'F.

2. For each change to or error discovered in an acceptable evaluation model or in the application of such a model that affects the temperature calculation, the applicant or licensee shall report the nature of the change or error and its estimated effect on the limiting ECCS analysis to the Commission at least annually as specified in 10CFR50.4.

3. If the change or error is significant, the applicant or licensee shall provide this report within 30 days and include with the report a proposed schedule for providing a reanalysis or taking other action as may be needed to show compliance with IOCFR50.46 requirements. This schedule may be developed using an integrated scheduling system previously approved for the facility by the NRC. For those facilities not using an NRC approved integrated scheduling system, a schedule will be established by the NRC staff within 60 days of receipt of the proposed schedule.

4. Any change or error correction that results in a calculated ECCS performance that does not conform to the criteria set forth in paragraph (b) of IOCFR50.46 is a reportable event as described in IOCFR50.55(e), 50.72 and 50.73. The affected applicant or licensee shall propose immediate steps to demonstrate compliance or bring plant design or operation into compliance with IOCFR50.46 requirements.

This report documents all the errors corrected in and/or changes to the presently licensed ECCS performance evaluation models for PWRs developed by Combustion Engineering, made in the Westinghouse Electric Company LLC I

CENPD -279, Supp. 15 year covered by this report, which have not been reviewed by the NRC staff. This document is provided to satisfy the reporting requirements of the second item above. Reports for earlier years are given in References 2-16.

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CENPD -279, Supp. 15 2.0 COMBUSTION ENGINEERING ECCS EVALUATION MODELS AND CODES Five evaluation models (EM) for ECCS performance analysis of PWRs developed by Combustion Engineering are described in topical reports, are licensed by the NRC, and are covered by the provisions of 10CFR50.46. The evaluation models for large break LOCA (LBLOCA) are the June 1985 EM and the 1999 EM. There are two evaluation models for small break LOCA (SBLOCA): the SBLOCA Evaluation Model (S IM) and the S2M SBLOCA EM.

Post-LOCA long term cooling (LTC) analyses use the LTC evaluation model.

Several digital computer codes are used to do ECCS performance analyses of PAWRs for the evaluation models described above that are covered by the provisions of IOCFR50.46. Those for LBLOCA calculations are CEFLASH-4A, COMPERC-I1, HCROSS, PARCH, STRIKIN-Il, and COMZIRC. CEFLASH-4AS is used in conjunction with COMPERC-II, STRIKIN-Il, and PARCH for SBLOCA calculations. The codes for post-LOCA LTC analyses are BORON, CEPAC, NATFLOW, and CELDA.

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CENPD -279, Supp. 15 3.0 EVALUATION MODEL CHANGES AND ERROR CORRECTIONS This section discusses all error corrections and model changes to the ECCS performance evaluation models for PWRs described in Section 2.0 that may affect the calculated PCT.

There were no changes to or errors in the ECCS evaluation models for PAWRs or changes to their operation for calendar year (CY) 2003 that affect the calculated cladding temperature.

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CENPD -279, Supp. 15

4.0 CONCLUSION

S There were no changes to or errors in the ECCS evaluation models for PWRs or their application for LBLOCA, SBLOCA, or post-LOCA long term cooling that affect the calculated cladding temperature during CY 2003.

The sum of the absolute magnitude of the changes in PCT calculated using the June 1985 EM for LBLOCA, including those from previous annual reports, References 2-16, remains less than 10 F.

The maximum impact on PCT calculated with the 1999 EM is less than 1.20 F. Plant specific LBLOCA considerations for each plant are discussed in Appendices A through G.

Previous plant specific PCT effects for both the SIM and S2M SBLOCA evaluation models are discussed in Appendices A through G of Reference 15. In addition, there is a generic effect on maximum cladding temperature for the SBLOCA SIM (due to the change in application of the SBLOCA S IM described in Reference 11) that is less than 30F. There is no previous generic accumulated change in cladding temperature for the S2M. The overall plant specific PCT effects for SBLOCA are summarized in Appendices A through G.

There is no PCT effect for the post-LOCA long term cooling evaluation model.

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CENPD -279, Supp. 15

5.0 REFERENCES

1. "Acceptance Criteria for Emergency Core Cooling Systems for Light Water Nuclear Power Reactors," Code of Federal Regulations, Title 10, Part 50, Section 50.46.

2. "Annual Report on C-E ECCS Codes and Methods for IOCFR50.46," CENPD-279, April, 1989.

3. "Annual Report on C-E ECCS Codes and Methods for IOCFR50.46," CENPD-279, Supplement 1, February, 1990.

4. "Annual Report on C-E ECCS Codes and Methods for IOCFR50.46," CENPD-279, Supplement 2, April, 1991.

5. "Annual Report on C-E ECCS Codes and Methods for IOCFR50.46," CENPD-279, Supplement 3, April, 1992.

6. "Annual Report on C-E ECCS Codes and Methods for IOCFR50.46," CENPD-279, Supplement 4, April, 1993.

7. "Annual Report on C-E ECCS Codes and Methods for IOCFR50.46," CENPD-279, Supplement 5, February, 1994.

8. "Annual Report on ABB C-E ECCS Performance Evaluation Models," CENPD-279, Supplement 6, February, 1995.

9. "Annual Report on ABB C-E ECCS Performance Evaluation Models," CENPD-279, Supplement 7, February, 1996.

10. "Annual Report on ABB CE ECCS Performance Evaluation Models," CENPD-279, Supplement 8, February, 1997.

11. "Annual Report on ABB CE ECCS Performance Evaluation Models," CENPD-279, Supplement 9, March, 1998.

12. "Annual Report on ABB CE ECCS Performance Evaluation Models," CENPD-279, Supplement 1O, February, 1999.

13. "Annual Report on ABB CE ECCS Performance Evaluation Models," CENPD-279, Supplement 11, March, 2000.

14. "Annual Report on Combustion Engineering ECCS Performance Evaluation Models for PWRs," CENPD-279, Supplement 12, April, 2001.

15. "Annual Report on Combustion Engineering ECCS Performance Evaluation Models for P\N'Rs," CENPD-279, Supplement 13, Rev. 1, April, 2002.

16. "Annual Report on Combustion Engineering ECCS Performance Evaluation Models for PWRs," CENPD-279, Supplement 14, Rev. 1, April, 2003.

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CENPD -279, Supp. 15 APPENDIX C SOUTHERN CALIFORNIA EDISON COMPANY Plant Specific Considerations for SONGS Units 2 and 3 Appendix C of the CY 2002 10CFR50.46 report for SONGS Units 2 and 3 in Reference 16 was revised in Reference C.1 to address a plant specific issue concerning the suction leg elevation. It concluded that there was no PCT effect for LBLOCA and a 30 F effect for SBLOCA.

The total effect on PCT is less than 1 F for all LBLOCA analyses of SONGS Units 2 and 3 done to date with the 1985 EM.

There are no new SBLOCA errors for Calendar Year 2003. The suction leg elevation error discussed in Reference C.1 produced a 31F effect. There is an additional 16'F plant specific effect due to the CEFLASH-4AS leak flow error previously reported in Appendix C of Reference

15. The total PCT effect for SBLOCA is 130F1 + 1160 F1 or 19'F.

Reference:

C.l DAR-OA-03-14, Rev. 0, "Calendar Year 2002 10CFR50.46 Report for SONGS Units 2

& 3," P. K. Doherty, September 15, 2003.

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Enclosure 2 (5 pages including this page)

2003 REPORTING PERIOD LOSS OF COOLANT ACCIDENT (LOCA) MARGIN

SUMMARY

SAN ONOFRE NUCLEAR GENERATING STATION UNITS 2 AND 3 Larae Break LOCA Table 1 provides a time line of the items which could affect the Large Break LOCA peak cladding temperature (PCT) for this reporting period. The 10 CFR 50.46 PCT limit of 2,200'F was not exceeded.

Table 1 Limiting Large Break LOCA PCT Unit 2 Unit 3 Limiting Large Break LOCA PCT End of2002 2,135 0 F 2,136 0 F Changes in PCT during 2003 due to:

a) Model changes or Model errors

• Cycle 11 N/A 0OF

• Cycle 12 0OF 00 F b ) Cycle Dependent Input Changes

• Cycle 11 N/A 0OF

• Cycle 12 0 F -7 OF Limiting Large Break LOCA PCT End of 2003 2,135 0F 2,129 0 F Page 1 of 4

The cumulative 10CFR50.46 model changes and model errors for the "Large Break LOCA June 1985 Evaluation Model" are shown in Table 2.

Table 2 Cumulative LBLOCA 10 CFR 50.46 Model Changes and Model Errors A,IA PCTI

• 11Unit3 i Cumulative LBLOCA 10 CFR 50.46 Model Changes and Model Errors Pnorto2003 <1OF <1OF Changes in LBLOCA PCT due to Model Changes and Model Errors Discoveredin 2003

• Cycle 11 N/A 0OF

• Cycle1220F 01 Cumulative LBLOCA 10 CFR 50.46 Model Changes and Model Errors End of2003 <1 OF c 1 OF

• Sum of the absolute magnitude of the 10 CFR 50.46 model changes and model errors.

Page 2 of 4

Small Break LOCA Table 3 provides a time line of the items which could affect the Small Break LOCA peak cladding temperature (PCT) for this reporting period. The SBLOCA 10 CFR 50.46 PCT limit of 2200'F was not exceeded, and remained bounded by the LBLOCA.

Table 3 Limiting Small Break LOCA PCT Unit 2 Unit 3 Limiting Small Break LOCA PCT End of2002 1,903 0 F 1,903 0 F Changes in PCT during 2003 due to:

a) Model changes or Model errors Cycle 11 N/A 0OF Cycle 12 0OF 0OF b ) Cycle Dependent Input Changes Cycle 11 N/A 0OF Cycle 12 0OF 00 F Limiting Small Break LOCA PCT l End of 2003 1,903 0F 1,903 0 F Page 3 of 4

The cumulative 10CFR50.46 model changes and model errors for the "Small Break LOCA S2M Evaluation Model" are shown in Table 4.

Table 4 Cumulative SBLOCA 10 CFR 50.46 Model Changes and Model Errors I,JA PCTJ

• ll Unit2 ll Unit3 Cumulative SBLOCA 10 CFR 50.46 Model Changes and Model Errors Priorto 2003 19 F 19 OF Changes in SBLOCA PCT due to Model Changes and Model Errors Discoveredin 2003

• Cycle 11 N/A 00 F

• Cycle 12 00 F 0OF l Cumulative SBLOCA 10 CFR 50.46 Model Changes and Model Errors End of 2003 19 OF 19F

• Sum of the absolute magnitude of the 10 CFR 50.46 model changes and model errors.

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