L-2004-066, Acceptance Criteria for Emergency Core Cooling Systems for Light Water Nuclear Power Reactors, 10CFR50.46 Annual Report

Acceptance Criteria for Emergency Core Cooling Systems for Light Water Nuclear Power Reactors, 10CFR50.46 Annual Report

ML040890445
Person / Time
Site:	Saint Lucie
Issue date:	03/25/2004
From:	Jefferson W Florida Power & Light Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
L-2004-066
Download: ML040890445 (4)

Text

Florida Power & Light Company. 6501 S. Ocean Drive, Jensen Beach, FL 34957 March 25, 2004 FPL L-2004-066 10 CFR 50.46 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 Re: St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 Acceptance Criteria for Emergency Core Cooling Systems for Light Water Nuclear Power Reactors 10 CFR 50.46 Annual Report Pursuant to 10 CFR 50.46(a)(3)(ii), the nature of any change to or error discovered in the evaluation models for emergency core cooling systems (ECCS), or in the application of such models, that affect the fuel cladding temperature calculations for St. Lucie Units 1 and 2 is reported in the attachment to this letter. The estimated effect from any such change or error on the limiting ECCS analysis for each unit is also addressed. The data interval for the report is from January 1, 2003 through December 31, 2003.

Please contact us should you have any questions regarding this submittal.

Willa r.

Vice P ident St. Lucie Plant WJ/spt Attachment an FPL Group company

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St. Lucie Plant Units I and 2 Docket Nos. 50-335 and 50-389 L-2004-066 Attachment Page 1 St. Lucie Units 1 and 2 10 CFR 50.46 Annual Report Emergency core cooling system (ECCS) analyses for St. Lucie Unit I and St. Lucie Unit 2 are performed by Framatome ANP, Inc. (FRA-ANP) and Westinghouse Electric Company (WJ, respectively. The following information pertaining to the evaluation models for small break loss of coolant accidents (SBLOCA) and large break loss of coolant accidents (LBLOCA), and the application of such models to each St. Lucie unit, is provided pursuant to 10 CFR 50.46(a)(3)(ii). A summary of calculated peak cladding temperature (PCT) changes is provided in Table 1. The data interval for this report is from January 1, 2003 through December 31, 2003.

1.0 ST. LUCIE UNIT I 1.1 No errors were found in the SBLOCA ECCS performance analysis since the previous report of Reference 3.1. The limiting SBLOCA PCT remains at 17660F.

1.2 Two errors/issues were identified impacting the LBLOCA PCT. These errors, not previously reported in Reference 3.1, are described below. Table 1 summarizes the estimated impact of these errors/issues on the St. Lucie Unit I LBLOCA PCT. The limiting LBLOCA PCT with the estimated effect of the changes is 2041 OF.

Error in Main Feedwater and Steam Isolation Times The analysis of record incorrectly used delay times of 0.05 and 1.45 seconds, and ramp rates corresponding to 2.0 and 0.3 seconds ramp for main feedwater and steam isolation, respectively. The delay times and flow ramps were changed to 0.05 and 0.1 seconds, respectively, in compliance with the analysis guidelines. The PCT impact of this error correction on the St. Lucie Unit I LBLOCA analysis is estimated to be +80F.

Error in Bubble Rise Model for Safety Iniection Tanks The analysis of record used values of 1.0 and 20.0 for the bubble gradient (ALPH) and velocity (VBUB), respectively, in the bubble rise model for the safety injection tanks.

The values were corrected to 0.8 and 3.0 for ALPH and VBUB, respectively, consistent with the analysis guidelines. The PCT impact of correcting these errors on the St. Lucie Unit 1 LBLOCA analysis is estimated to be 00F.

2.0 ST. LUCIE UNIT 2 2.1 No errors were found in the SBLOCA analysis impacting the PCTs previously reported in References 3.1 and 3.2. The limiting PCT for SBLOCA is 2132.60F.

O- ;

St. Lucie Plant Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2004-066 Attachment Page 2 2.2 No errors were found in the LBLOCA analysis since those reported in Reference 3.3.

Two PCT estimates reported in Reference 3.3 were revised in the final verification process: i) estimate for the model change is revised from -1400 F to -1490 F (correction of -90F) and ii estimate for the k-factor error is revised from +1100F to +1090 F (correction of -I F). The limiting PCT for LBLOCA is 21260F.

3.0 REFERENCES

3.1 FPL Letter L-2003-078, D. E. Jernigan to USNRC Document Control Desk, 'St. Lucie Units 1 and 2, Docket Nos. 50-335 and 50-389, Acceptance Criteria for Emergency Core Cooling Systems for Light Water Nuclear Power Reactors: 10 CFR 50.46 Annual Report," March 26, 2003 3.2 FPL Letter L-2002-196, D. E. Jernigan to USNRC Document Control Desk, uSt. Lucie Unit 2, Docket No. 50-389, Proposed License Amendment: Reduce the Minimum Reactor Coolant System Flow," October 15, 2002 3.3 FPL Letter L-2003-227, W. Jefferson, Jr. to USNRC Document Control Desk, 'St. Lucie Unit 2, Docket No. 50-389, LBLOCA Evaluation Model: 30-Day 10 CFR 50.46 Report,"

September 10, 2003

i.

St. Lucie Plant Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2004-066 Attachment Page 3 Table 1: 2003 St. Lucie Units 1 and 2 SBLOCA and LBLOCA PCT Summary Unit I SBLOCA Summary POT Year 2002 10 CFR 50.46 Annual Report (L-2003-078) 17660F Change during Year 2003 OOF Year 2003 10 CFR 50.46 Annual Report 17660 F Unit I LBLOCA Summary PCT Year 2002 10 CFR 50.46 Annual Report (L-2003-078) 20330F Change due to error in main feedwater and steam isolation times 80F Change due to error in bubble rise model for safety injection 0F tanks Year 2003 10 CFR 50.46 Annual Report 2041OF Unit 2 SBLOCA Summary PCT Year 2002 10 CFR 50.46 Annual Report (L-2003-078) 21250F Change due to RCS flow reduction from 363,000 gpm to 355,000 760 gpm, previously reported in L-2002-196 Year 2003 10 CFR 50.46 Annual Report 2132.6 F Unit 2 LBLOCA Summary PCT Year 2002 10 CFR 50.46 Annual Report (L-2003-078) 2151 F 30-Day 10 CFR 50.46 Report (L-2003-227) 21360F Correction to the PCT estimate, previously reported in L-2003- -90F 227, for 1985 EM to 1999 EM model change Correction to the PCT estimate, previously reported in L-2003- -10F 227, for locked-rotor k-factor error Year 2003 10 CFR 50.46 Annual Report 21260 F