ML082390087

CFR 50.46 Annual Report

ML082390087
Person / Time
Site:	Peach Bottom
Issue date:	08/22/2008
From:	David Helker Exelon Generation Co, Exelon Nuclear
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML082390087 (11)

Text

Exelon Nuclear www.exeloncorp.com 200 Exelon Way Nuclear Kennett Square, PA 19348 10 CFR 50.46 August 22, 2008 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 David P. Helker (Exelon Generation Company, LLC) to U. S. Nuclear Regulatory Commission, "10 CFR 50.46 Report,"

dated August 22, 2007 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 22,2007.

Since the Reference 1 report was issued, no vendor notifications of Emergency Core Cooling System (ECCS) model error/changes 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 Loss of Coolant Accident (LOCA) Analysis

U.S. Nuclear Regulatory Commission PBAPS, Units 2 and 3 10 CFR 50.46 Report August 22, 2008 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.

Respectfully, 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, 2008 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, 2008 Attachment 1 Peak Cladding Temperature Rack-Up Sheet, PBAPS U2 Page 1 of 2 PLANT NAME: Peach Bottom Unit 2 ECCS EVALUATION MODEL: SAFERIGESTR-LOCA REPORT REVISION DATE: 08/22/08 CURRENT OPERATING CYCLE: 17 ANALVSIS OF RECORD Evaluation Model:

1. 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 BWR Loss-Of-Coolant Analysis," October 1984.

2. 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 BWR Loss-of-Coolant Analysis," October 1987.

3. NEDC-32950P, "Compilation of Improvements to GENE's SAFER ECCS-LOCA Evaluation Model," January 2000.

4. NEDC-23785-1-PA Rev. 1, The GESTR-LOCA and SAFER Models for the Evaluation of the Loss-Of-Coolant Accident Volume III, SAFERIGESTR 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-J11-03716-09-02P, July 2000.

3. Errata & Addendum No.1 to GENE-J11-03716-09-02P, "Peach Bottom Atomic Power Station ECCS-LOCA Evaluation for GE14," October 2007.

Fuel Analyzed in Calculations: P8x8R, GE9, GE11/13 and GE14 Limiting Fuel Type: GE14 (Note: P8x8R, GE9 and GE11/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, 2008 Attachment 1 Peak Cladding Temperature Rack-Up Sheet, PBAPS U2 Page 2 of 2 MARGIN ALLOCATION A. PRIOR LOCA MODEL ASSESSMENTS 10 CFR 50.46 Report dated June 4, 2001 (See Note 1) GE14 LlPCT = 55°F 10 CFR 50.46 Report dated December 18, 2002 (See Note 2) GE14 LlPCT = 45°F 10 CFR 50.46 Report dated December 03, 2004 (See Note 3) GE14 LlPCT = OaF 10 CFR 50.46 Report dated December 01,2005 (See Note 4) GE14 LlPCT = OaF 10 CFR 50.46 Report dated August 22, 2006 (See Note 5) GE14 LlPCT = 150°F 10 CFR 50.46 Report dated August 22, 2007 (See Note 6) GE14 LlPCT = OaF Net PCT lGE141 1700 of B. CURRENT LOCA MODEL ASSESSMENTS None GE14 LlPCT = OaF Total PCT change from current assessments (GE14) LLlPCT = OaF Cumulative PCT change from current assessments (GE14) L ILlPCT I = OaF Net peT (GE14) 1700 of

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, 2008 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, 2008 Attachment 2 Peak Cladding Temperature Rack-Up Sheet, PBAPS U3 Page 1 of 2 PLANT NAME: Peach Bottom Unit 3 ECCS EVALUATION MODEL: SAFERIGESTR-LOCA REPORT REVISION DATE: 08/22/08 CURRENT OPERATING CYCLE: 17 ANALYSIS OF RECORD Evaluation Model:

1. NEDC-23785-1-PA Rev. 1, The GESTR-LOCA and SAFER Models tor the Evaluation ot the Loss-Ot-Coolant Accident Volume II, SAFER - Long Term Inventory Model tor BWR Loss-Ot-Coolant Analysis," October 1984.

2. NEDC-30996P-A, "SAFER Model tor Evaluation of Loss-ot-Coolant Accidents tor Jet Pump and Non-jet Pump Plants, Volume I, SAFER - Long Term Inventory Model tor BWR Loss-ot-Coolant Analysis," October 1987.

3. NEDC-32950P, "Compilation ot Improvements to GENE's SAFER ECCS-LOCA Evaluation Model," January 2000.

4. NEDC-23785-1-PA Rev. 1, The GESTR-LOCA and SAFER Models tor the Evaluation ot the Loss-Ot-Coolant Accident Volume III, SAFER/GESTR Application Methodology," October 1984.

(Jet Pump Plant - SAFER)

Calculations:

1. "Peach Bottom Atomic Power Station, Units 2 and 3 SAFERIGESTR-LOCA Loss-ot-Coolant Accident Analysis," NEDC-32163P, January 1993.

2. "Peach Bottom Atomic Power Station ECCS-LOCA Evaluation tor GE14", General Electric Company, GENE-J11-03716-09-02P, July 2000.

3. Errata & Addendum No.1 to GENE-J11-03716-09-02P, "Peach Bottom Atomic Power Station ECCS-LOCA Evaluation tor GE14," October 2007.

Fuel Analyzed in Calculations: P8x8R, GE9, GE11/13 and GE14 Limiting Fuel Type: GE14 (Note: P8x8R, GE9 and GE11/GE13 are no longer in operation and are not considered tor detining the limiting tuel type)

Limiting Single Failure: Battery Failure Limiting Break Size and Location: 0.08 ft2 Small Break in a Recirculation Discharge Pipe Reterence 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, 2008 Attachment 2 Peak Cladding Temperature Rack-Up Sheet, PBAPS U3 Page 2 of 2 MARGIN ALLOCATION A. PRIOR LOCA MODEL ASSESSMENTS 10 CFR 50.46 Report dated June 4, 2001 (See Note 1) GE14 ~PCT =55°F 10 CFR 50.46 Report dated December 18, 2002 (See Note 2) GE14 ~PCT =45°F 10 CFR 50.46 Report dated December 03, 2004 (See Note 3) GE14 ~PCT =QOF 10 CFR 50.46 Report dated December 01, 2005 (See Note 4) GE14 ~PCT = QOF 10 CFR 50.46 Report dated August 22, 2006 (See Note 5) GE14 ~PCT = 15QOF 10 CFR 50.46 Report dated August 22, 2007 (See Note 6) GE14 ~PCT =QOF Net PCT (GE14) 1700 of B. CURRENT LOCA MODEL ASSESSMENTS None GE14 ~PCT =QOF Total PCT change from current assessments (GE14) L~PCT =QOF Cumulative PCT change from current assessments (GE14) L I~PCT I =QOF Net PCT (GE14) 1700 of

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, 2008 Attachment 3 Assessment Notes, PBAPS, Units 2 and 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 45°F 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 55°F.

[

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.]

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 40°F and 5°F, respectively. These PCT errors applied to all fuel types. The total PCT impact of these errors on GE14 fuel was determined to be 45°F.

[

Reference:

Letter from Michael P. Gallagher (Exelon) to U. S. NRC, "10 CFR 50.46 Reporting Requirements," dated December 18, 2002.]

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 level/volume table error, a SAFER separator pressure drop error and a new heat source. The PCT impact for the new errors was determined to be OaF for each error. The total PCT impact of these errors on GE14 fuel was determined to be OaF.

[

Reference:

Letter from Michael P. Gallagher (Exelon Generation Company, LLC) to U.

S. Nuclear Regulatory Commission, "10 CFR 50.46 Annual Report," dated December 03,2004.]

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 OaF.

[

Reference:

Letter from Pamela B. Cowan (Exelon Generation Company, LLC) to U. S.

Nuclear Regulatory Commission, "10 CFR 50.46 Annual Report," dated December 01 ,

2005.]

Report of the Emergency Core Cooling System Evaluation Model Changes and Errors Assessments as of August 22, 2008 Attachment 3 Assessment Notes, PBAPS, Units 2 and 3 Page 2 of 2

5. Prior LOCA Assessment 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 150°F 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 B. Cowan (Exelon Generation Company, LLC) to U. S.

Nuclear Regulatory Commission, "10 CFR 50.46 30-Day Report," dated August 22, 2006.]

6. 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 OaF.

[

Reference:

Letter from David P. Helker (Exelon Generation Company, LLC) to U. S.

Nuclear Regulatory Commission, "10 CFR 50.46 Annual Report," dated August 22, 2007.]

7. Current LOCA Assessment None