RS-09-045, Plant Specific ECCS Evaluation Changes - 10 CFR 50.46 Report
| ML090861014 | |
| Person / Time | |
|---|---|
| Site: | LaSalle  |
| Issue date: | 03/27/2009 |
| From: | Simpson P Exelon Generation Co, Exelon Nuclear |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| RS-09-045 | |
| Download: ML090861014 (6) | |
Text
lxeion Nuclear www,exeiencorp-cor*
4300 W infield Read VVarrenvlle,1L 6c5S5 March 27, 2009 U. S. Nuclear Regulatory Commission ATTN : Document Control Desk Washington, DC 20555-0001 LaSalle County Station, Units 1 and 2 Facility Operating License Nos. NPF-11 and NPF-18 NRC Docket Nos. 50-373 and 50-374
Subject:
Plant Specific ECCS Evaluation Changes - 10 CFR 50.46 Report a-Exe1%
Nuclear RS-09-045 10 C FR 50.46 Reference :
Letter from D. P. Rhoades (Exelon Generation Company, LLC) to U. S. NRC, "Plant Specific ECCS Evaluation Changes - 10 CFR 50.46 Report," dated March 28, 2008 In accordance with 10 CFR 50.46, "Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors," Exelon Generation Company, LLC (EGC) is submitting the attached information to fulfill the annual reporting requirements for LaSalle County Station (LSCS), Units 1 and 2.
In the referenced letter, EGC reported a fuel peak cladding temperature (PCT) of 1460°F for Units 1 and 2 for the General Electric (GE) fuel, calculated based on an acceptable model. For the current reporting period, there is a 10°F increase, to 1470°F, in the PCT for the GE fuel.
The referenced letter also provided a fuel PCT of 1729°F for Units 1 and 2 for the AREVA NP (formerly Framatome Advanced Nuclear Power (FANP)) fuel, calculated based on an acceptable model. For the current reporting period, there is no change in the PCT for the AREVA NP fuel.
Unit 1 and Unit 2 employ a mixed core design containing co-resident GE and AREVA NP fuel.
The loss-of-coolant accident (LOCA) analyses of record for both GE and AREVA NP fuel are within the acceptance criteria set forth in 10 CFR 50.46.
Attachments 1 and 2 provide the PCT information for the limiting LOCA evaluations for LSCS, Units 1 and 2, as of February 12, 2009. The assessment notes are contained in Attachment 3 and provide a detailed description for each change reported.
March 27, 2009 U. S. Nuclear Regulatory Commission Page 2 There are no regulatory commitments contained in this letter.
If you have any questions concerning this letter, please contact Mr. Kenneth M. Nicely at (630) 657-2803.
Respectfully, Patrick R. Simpson Manager - Licensing Attachments:
1.
LaSalle County Station, Units 1 and 2, 10 CFR 50.46 Report (GE Fuel) 2.
LaSalle County Station, Units 1 and 2, 10 CFR 50.46 Report (AREVA NP Fuel)
- 3.
LaSalle County Station, Units 1 and 2, 10 CFR 50.46 Report (Assessment Notes) cc :
Regional Administrator - NRC Region III NRC Senior Resident Inspector-LaSalle County Station
ATTACHMENT 1 LaSalle County Station, Units 1 and 2, 10 CFR 50.46 Report (GE Fuel)
PLANT NAME :
LaSalle County Station, Units 1 and 2 ECCS EVALUATION MODEL :
SAFER/GESTR LOCH REPORT REVISION DATE :
February 12, 2009 CURRENT OPERATING CYCLES :
L1C13 and L2C13 ANALYSIS OF RECORD Evaluation Model Methodology:
NEDE-23785-1-PA, Rev. 1, "GESTR-LOCH and SAFER Models for the Evaluation of the Loss-of-Coolant Accident (Volume III), SAFER/GESTR Application Methodology," October 1984.
Calculation :
GE-NE-0000-0022-8684-R2, "Exelon LaSalle Units 1 and 2 SAFER/GESTR Loss-of-Coolant Accident Analysis for GE 14 Fuel," November 2006.
Fuel :
GE14 Limiting Single Failure:
High Pressure Core Spray Diesel Generator Limiting Break Size and 0.08 ft2 Recirculation Pump Suction Line Break Location :
Reference Peack Cladding 1460°F Temperature (PCT) :
MARGIN ALLOCATION A. PRIOR LOSS-OF-COOLANT ACCIDENT (LOCA) MODEL ASSESSMENTS B. CURRENT LOCA MODEL ASSESSMENTS 10 CFR 50.46 report dated August 28, 2006 (Note 1)
APCT = 0°F 10 CFR 50.46 report dated March 30, 2007 (Note 3)
APCT = 0°F 10 CFR 50.46 report dated March 28, 2008 (Note 4)
APCT = 0°F Net PCT 1460°17 Steam Flow Induced Error (Note 5
-~ APCT = 10°F Total PCT change from_
current assessments Y-APCT = 10°F Cumulative PCT change from current assessments Y-APCT = 10°F Net PCT 1470`17
ATTACHMENT 2 LaSaIle County Station, Units 1 and 2, 10 CFR 50.46 Report (AREVA NP Fuel)
PLANT NAME :
ECCS EVALUATION MODEL:
REPORT REVISION DATE :
CURRENT OPERATING CYCLES :
ANALYSIS OF RECORD Evaluation Model Methodology:
Calculation:
Fuel :
Limiting Single Failure :
Limiting Break Size and Location :
Reference Peak Cladding Temperature (PCT):
B. CURRENT LOCA MODEL ASSESSMENTS LaSaIle County Station, Units 1 and 2 EXEM BWR-2000 Evaluation Model February 12, 2009 LlC13 and L2C13 EMF-2361 (P)(A) Revision 0, EXEM BWR-2000 ECCS Evaluation Model, Framatome ANP, May 2001.
EMF-3230 (P) Revision 0, LaSaIle Units 1 and 2 EXEM BWR-2000 LOCA Break Spectrum Analysis for ATRIUM - 10 Fuel, November 2005.
EMF-3231 (P) Revision 0, LaSaIle Units 1 and 2 EXEM BWR-2000 LOCA-ECCS Analysis MAPLHGR Limit for ATRIUM - 10 Fuel, November 2005.
ATRIUM-10 Low Pressure Coolant Injection Diesel Generator Double Ended Guillotine/0.8 discharge coefficient of Recirculation Pump Suction Piping 1729°F MARGIN ALLOCATION A. PRIOR LOSS-OF-COOLANT ACCIDENT (LOCA) MODEL ASSESSMENTS 10 CFR 50.46 report dated August 28, 2006 (Note 2)
APCT = 0`F 10 CFR 50.46 report dated March 30, 2007 (Note 3)
APCT = 0°F 10 CFR 50.46 report dated March 28, 2008 (Note 4)
APCT = 0°F Net PCT F
- 1729°F I ATRIUM-10 XM Lead Test Assembliesfote 5Z - - - --
APCT = 0°F Total PCT chan e from current assessments assessments
=-0'F 1APCT I APCT !=0-F Net PCT 1729°F
ATTACHMENT 3 LaSalle County Station, Units 1 and 2, 10 CFR 50.46 Report (Assessment Notes) 1. Prior Loss-of-Coolant Accident (LOCA) Model Assessment for General Electric (GE) Fuel To address the impact of axial power shape on the small break LOCA (SBLOCA) a complete SBLOCA break spectrum analysis was performed in November 2006. Additionally all reported 10 CFR 50.46 errors/issues that affect the small break Emergency Core Cooling Systems (ECCS) LOCA analysis have been accounted for in this analysis. As reported in the referenced letter, the large break LOCA (LBLOCA) is non-limiting. There are no input errors, code errors, or modeling changes that have been identified which would require adjustment to the LBLOCA results reported in the referenced letter.
[Reference : Letter from D. J. Enright (Exelon Generation Company, LLC) to U. S. NRC, "Plant Specific ECCS Evaluation Changes -10 CFR 50.46 Report," dated August 28, 2006.]
2.
Prior LOCA Model Assessment for AREVA NP Fuel An AREVA NP (formerly FANP) LOCA evaluation was performed in November 2005 due to the discharge of ATRIUM-9 fuel and the reanalysis of the ATRIUM-10 fuel for cycle L1 C12.
This analysis was reported to the NRC in the referenced letter. The AREVA NP analysis for cycle L2C12 demonstrated that the LOCA analysis performed for cycle L1 C12 in November 2005 is applicable to cycle L2C12. Since the performance of the November 2005 LOCA analysis, no input errors, code errors, or modeling changes have been identified which would require adjustment to the results. The referenced letter also provided the Unit 2 peak cladding temperature (PCT) of 1832°F (i.e., including all assessments) for the AREVA NP fuel based on an acceptable model for a mixed core of ATRIUM-9 and ATRIUM-10, with ATRIUM-9 being the limiting fuel type. Since the last evaluation, ATRIUM-9 fuel has been discharged from the Unit 2 core, making ATRIUM-10 fuel the limiting fuel type. Because the PCT for the ATRIUM-10 fuel for Unit 2 is 1729°F, this is a change of over 50°F from the last evaluation using an NRC approved acceptable model.
For Unit 1, there were no changes for ATRIUM-10 fuel and the PCT remains at 1729°F.
[Reference : Letter from D. J. Enright (Exelon Generation Company, LLC) to U. S. NRC, "Plant Specific ECCS Evaluation Changes - 10 CFR 50.46 Report," dated August 28, 2006.]
- 3.
Prior LOCA Model Assessment for GE and AREVA NP Fuel The 10 CFR 50.46 report submitted to the NRC in the referenced letter did not report any LOCA model assessments for GE fuel or AREVA NP fuel.
[Reference : Letter from D. J. Enright (Exelon Generation Company, LLC) to U. S. NRC, "Plant Specific ECCS Evaluation Changes -10 CFR 50.46 Report," dated March 30, 2007.]
- 4.
Prior LOCA Model Assessment for GE and AREVA NP Fuel During the performance of the Unit 2 Reload 11 outage inspection of the Core Spray sparger, a bent flow deflector in one of the High Pressure Core Spray sparger nozzles was noted.
Both GE and AREVA NP performed an evaluation and determined that the impact of this bent flow deflector on the LOCA analyses was insignificant. A zero degree PCT impact was assigned. This evaluation was reported to the NRC in the referenced letter.
This PCT impact was only applicable to Unit 2.
Page 1 of 2
ATTACHMENT 3 LaSalle County Station, Units 1 and 2, 10 CFR 50.46 Report (Assessment Notes)
[Reference : Letter from D. P. Rhoades (Exelon Generation Company, LLC) to U. S. NRC, "Plant Specific ECCS Evaluation Changes-10 CFR 50.46 Report," dated March 28, 2008.]
5.
Current LOCA Model Assessment for GE and AREVA NP Fuel The steam flow induced error (SFIE), or Bernoulli Error, affects the Level 3 water level measurements, where water level could reach the bottom of the dryer and allow steam to bypass to the annulus. This error resulted in a 10°F PCT penalty for GE fuel. The AREVA NP LOCA evaluation was not impacted by this error.
During the Unit 2 Reload 12 outage, eight ATRIUM-1 0XM lead test assemblies (LTAs) were loaded into the cycle L2C13 core. The PCT of the ATRIUM-10XM LTAs was less than the PCT for ATRIUM-10 fuel. The cycle L1 C13 core does not have any ATRIUM-10XM fuel.