ML072340617

10 CFR 50.46 Annual Report

ML072340617
Person / Time
Site:	Peach Bottom
Issue date:	08/22/2007
From:	David Helker Exelon Nuclear
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML072340617 (11)

Text

Exelon Nuclear www.exeloncorp.com 200 Exelon Way Kennett Square, PA 19348 N ucl ear 1 OCFR50.46 August 22,2007 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 Peach Bottom Atomic Power Station, Units 2 and 3 Renewed Facility Operating License Nos. DPR-44 and DPR-56 NRC Docket Nos. 50-277 and 50-278 Subject : 10 CFR 50.46 Annual Report

References:

1. Letter from Pamela B. Cowan (Exelon Generation Company, LLC) to U. S. Nuclear Regulatory Commission, "10 CFR 50.46 30-Day Report," dated August 22, 2006 The purpose of this letter is to transmit the 10 CFR 50.46 reporting information for Peach Bottom Atomic Power Station (PBAPS), Units 2 and

3. The previous 50.46 report for PBAPS, Units 2 and 3 (Reference

1) provided the cumulative Peak Cladding Temperature (PCT) errors for the most recent fuel designs through August 22, 2006. Since the Reference 1 report was issued, no vendor notifications of Emergency Core Cooling System (ECCS) model errorkhanges that are applicable to PBAPS, Units 2 and 3 have been issued.

Also, no ECCS-related changes or modifications have occurred at PBAPS, Units 2 and 3 that affect the assumptions of the ECCS analyses.

Three attachments are included with this letter that provide the current PBAPS, Units 2 and 3 10 CFR 50.46 status. Attachments 1 and 2, "Peak Cladding Temperature Rack- Up Sheet," provide information regarding the PCT for the limiting Large Break Loss of USNRC PBAPS 10 CFR 50.46 Annual Report August 22,2007 Page 2 Coolant Accident (LOCA) Analysis evaluations for PBAPS, Units 2 and 3, respectively.

Attachment 3, "Assessment Notes," contains a detailed description for each change or error reported.

If you have any questions, please contact Tom Loomis at 610-765-5510.

Very truly yours, David P. Helker Manager - Licensing Attachments:

1) Peak Cladding Temperature Rack-Up Sheet (Peach Bottom Atomic Power Station , Unit 2) 2) Peak Cladding Temperature Rack-Up Sheet (Peach Bottom Atomic Power Station , Unit 3) 3) Assessment Notes cc: S. J. Collins, USNRC Administrator, Region I J. Hughey, USNRC Project Manager, PBAPS F. Bowers, USNRC Senior Resident Inspector, PBAPS ATTACHMENT 1 10 CFR 50.46 "Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors" Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of August 22,2007 Peak Cladding Temperature Rack-Up Sheet Peach Bottom Atomic Power Station, Unit 2 Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of August 22,2007 Peak Cladding Temperature Rack-Up Sheet, PBAPS U2 Attachment 1 Page 1 of 2 PLANT NAME: REPORT REVISION DATE: CURRENT OPERATING CYCLE: 17 Peach Bottom Unit 2 0 8/22/0 7 ECCS EVALUATION MODEL: SAFER/GESTR-LOCA ANALYSIS OF RECORD Evaluation Model:

1. 2. 3. 4. NEDC-23785-1 -PA Rev. 1, "The GESTR-LOCA and SAFER Models for the Evaluation of the Loss-Of-Coolant Accident Volume II, SAFER - Long Term Inventory Model for BW R Loss-Of-Coolant Analysis," October 1984.

NEDC-30996P-A, "SAFER Model for Evaluation of Loss-of-Coolant Accidents for Jet Pump and Non-jet Pump Plants, Volume I, SAFER - Long Term Inventory Model for BW R Loss-of-Coolant Analysis," October 1987. NEDC-32950P, "Compilation of Improvements to GENE'S SAFER ECCS-LOCA Evaluation Model," January 2000.

NEDC-23785-1 -PA Rev. I, "The GESTR-LOCA and SAFER Models for the Evaluation of the Loss-Of-Coolant Accident Volume Ill, SAFER/GESTR Application Methodology," October 1984. (Jet Pump Plant - SAFER) Calculations:

1. "Peach Bottom Atomic Power Station, Units 2 and 3 SAFER/GESTR-LOCA Loss-of- Coolant Accident Analysis", NEDC-32163P, January 1 993. 2. "Peach Bottom Atomic Power Station ECCS-LOCA Evaluation for GE14, General Electric Company, GENE-JI1-03716-09-02P, July 2000.

Fuel Analyzed in Calculations:

P8x8R, GE9, GEI 1/13 and GE14 Limiting Fuel Type: GE14 (Note: P8x8R, GE9 and GEI 1/GEl3 are no longer in operation and are not considered for defining the limiting fuel type) Limiting Single Failure: Battery Failure Limiting Break Size and Location: 0.08 ft2 Small Break in a Recirculation Discharge Pipe Reference Peak Cladding Temperature (PCT) - GE14 PCT = 1450°F Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of August 22,2007 Peak Cladding Temperature Rack-Up Sheet, PBAPS U2 10 CFR 50.46 Report dated June 4,2001 (See Note

1) 10 CFR 50.46 Report dated December 18,2002 (See Note 2) 10 CFR 50.46 Report dated December 03,2004 (See Note

3) 10 CFR 50.46 Report dated December 01,2005 (See Note

4) 10 CFR 50.46 ReDort dated Auaust 22.2006 (See Note

5) MARGIN ALLOCATION GE14 APCT = 55°F GE14 APCT = 45°F GE14 APCT = 0°F GE14 APCT = 0°F GE14 APCT = 150°F A. PRIOR LOCA MODEL ASSESSMENTS None Total PCT change from current assessments (GE14)

Cumulative PCT change from current assessments (GEI 4) Attachment 1 Page 2 of 2 GE14 APCT = 0°F CAPCT = 0°F c 1 APCT I = OOF Net PCT (GE14) 1700 OF - B. CURRENT LOCA MODEL ASSESSMENTS ATTACHMENT 2 10 CFR 50.46 "Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors" Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of August 22,2007 Peak Cladding Temperature Rack-Up Sheet Peach Bottom Atomic Power Station, Unit 3 Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of August 22,2007 Peak Cladding Temperature Rack-Up Sheet, PBAPS U3 PLANT NAME: REPORT REVISION DATE:

08/22/07 CURRENT OPERATING CYCLE: 16 Peach Bottom Unit 3 ECCS EVALUATION MODEL: SAFE R/G ESTR-LOCA ANALYSIS OF RECORD Eva1 uat ion Model : Attachment 2 Page 1 of 2 NEDC-23785-1 -PA Rev. 1, 'The GESTR-LOCA and SAFER Models for the Evaluation of the Loss-Of-Coolant Accident Volume II, SAFER - Long Term Inventory Model for BW R Loss-Of-Coolant Analysis," October 1984.

NEDC-30996P-A, "SAFER Model for Evaluation of Loss-of-Coolant Accidents for Jet Pump and Non-jet Pump Plants, Volume I, SAFER - Long Term Inventory Model for BW R Loss-of-Coolant Analysis," October 1 987. NEDC-32950P, "Compilation of Improvements to GENE'S SAFER ECCS-LOCA Evaluation Model," January 2000. NEDC-23785-1 -PA Rev. 1, 'The GESTR-LOCA and SAFER Models for the Evaluation of the Loss-Of-Coolant Accident Volume I I I, SAFER/GESTR Application Methodology," October 1984. (Jet Pump Plant - SAFER) Calculations:

1. "Peach Bottom Atomic Power Station, Units 2 and 3 SAFER/GESTR-LOCA Loss-of- Coolant Accident Analysis

", NEDC-32163P, January 1993.

2. "Peach Bottom Atomic Power Station ECCS-LOCA Evaluation for GE14", General Electric Company, GENE-JI1-03716-09-02P, July 2000. Fuel Analyzed in Calculations: P8x8R, GE9, GEI 1/13 and GE14 Limiting Fuel Type: GE14 (Note: P8x8R, GE9 and GEiI/GE13 are no longer in operation and are not considered for defining the limiting fuel type) Limiting Single Failure: Battery Failure Limiting Break Size and Location: 0.08 ft2 Small Break in a Recirculation Discharge Pipe Reference Peak Cladding Temperature (PCT) - GE14 PCT = 1450°F Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of August 22,2007 Peak Cladding Temperature Rack-Up Sheet, PBAPS U3 10 CFR 50.46 Report dated June 4,2001 (See Note

1) 10 CFR 50.46 ReDort dated December 18.2002 (See Note

2) MARGIN ALLOCATION GE14 APCT = 55°F GE14 APCT = 45°F A. PRIOR LOCA MODEL ASSESSMENTS 10 CFR 50.46 Report dated December 03,2004 (See Note 3) 10 CFR 50.46 Report dated December 01,2005 (See Note 4) 10 CFR 50.46 Report dated August 22,2006 (See Note

5) Attachment 2 Page 2 of 2 GE14 APCT = 0°F GE14 APCT = 0°F GE14 APCT = 150°F 9 1700 OF None Total PCT change from current assessments (GE14) Cumulative PCT chanae from current assessments (GEI 4) GE14 APCT = 0°F CAPCT = 0°F c IAPCT I = OOF B. CURRENT LOCA MODEL ASSESSMENTS ATTACHMENT 3 10 CFR 50.46 "Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors" Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessment Notes Peach Bottom Atomic Power Station, Units 2 and 3 Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of August 22,2007 Assessment Notes, PBAPS, Units 2 and 3 Attachment 3 Page 1 of 2 1. Prior LOCA Assessment The referenced letter reported two GE LOCA errors related to a SAFER condensation error and a SAFER pressure rate error.

The PCT impact for the new errors was determined to be 45OF and 10°F, respectively. These PCT errors applied to all fuel types. This letter constituted a 30-Day report. The total PCT impact of these errors on GE14 fuel was determined to be 55OF. [

Reference:

Letter from J. A. Hutton (PECO Nuclear) to U.S. NRC, "Peach Bottom Atomic Power Station, Units 2 and 3 10 CFR 50.46 Reporting Requirements", dated June 4,2001.1 2. Prior LOCA Assessment The referenced letter provided the annual 50.46 report for Units 2 and 3. This letter reported GE LOCA errors related to a SAFER core spray sparger elevation error and a SAFER bulk water level error. The PCT impact for the new errors was determined to be 4OoF and 5OF, respectively. These PCT errors applied to all fuel types. The total PCT impact of these errors on GE14 fuel was determined to be 45OF. [

Reference:

Letter from Michael P. Gallagher (Exelon) to U.S. NRC, "10 CFR 50.46 Reporting Requirements", dated December 18, 2002.1 3. Prior LOCA Assessment The referenced letter provided the annual 50.46 report for Units 2 and 3. This letter reported GE LOCA errors related to a GESTR file interpolation error, a SAFER computer platform change, a WEVOL S1 volume error, a SAFER IeveVvolume table error, a SAFER separator pressure drop error and a new heat source.

The PCT impact for the new errors was determined to be O°F for each error. The total PCT impact of these errors on GE14 fuel was determined to be O°F. [

Reference:

Letter from Michael P. Gallagher (Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, "1 0 CFR 50.46 Annual Report", dated December 03, 2004.1 4. Prior LOCA Assessment The referenced letter provided the annual 50.46 report for Units 2 and 3. This letter reported that no vendor 50.46 change/error notifications had been received since the last annual report. Therefore, the annual PCT change for GE14 fuel was reported as O°F. [

Reference:

Letter from Pamela B. Cowan (Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, "1 0 CFR 50.46 Annual Report", dated December 01, 2005.1 Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of August 22,2007 Assessment Notes, PBAPS, Units 2 and 3 5. Prior LOCA Assessment Attachment 3 Page 2 of 2 The referenced letter provided a 30-Day 50.46 report for Units 2 and 3. This letter reported a newly discovered sensitivity to the assumed axial power shape for small break LOCA cases. This sensitivity may result in higher calculated PCT values for top- peaked axial power shapes. Due to this sensitivity, the calculated PCT for Peach Bottom was higher than the previously calculated value. The PCT impact was determined to be 1 5OoF for GE14 fuel. The 0.08 ft2 Small Break in a Recirculation Discharge Pipe is the Licensing Basis PCT event for Peach Bottom for GE14 fuel. [

Reference:

Letter from Pamela

6. Cowan (Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, "1 0 CFR 50.46 30-Day Report", dated August 22, 2006.1 6. Current LOCA Assessment None