ML12079A287
| ML12079A287 | |
| Person / Time | |
|---|---|
| Site: | Kewaunee  |
| Issue date: | 03/15/2012 |
| From: | Jordan A Dominion Energy Kewaunee |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 12-100 | |
| Download: ML12079A287 (17) | |
Text
Dominion Energy Kewaunee, Inc.
N490 Hwy 42. Kewaunee, W1 54216 ftminion oif Web Address: www.dom.com March 15, 2012 ATTN: Document Control Desk Serial No.12-100 U. S. Nuclear Regulatory Commission LIC/JG/R0 11555 Rockville Pike Docket No.: 50-305 Rockville, MD 20852-2738 License No.: DPR-43 DOMINION ENERGY KEWAUNEE. INC.
KEWAUNEE POWER STATION RESPONSE TO INFORMATION REQUEST PURSUANT TO 10 CFR 50.54(f)
RELATED TO THE ESTIMATED EFFECT ON PEAK CLADDING TEMPERATURE RESULTING FROM THERMAL CONDUCTIVITY DEGRADATION IN THE WESTINGHOUSE FURNISHED REALISTIC EMERGENCY CORE COOLING SYSTEM (ECCS) EVALUATION AND 30-DAY REPORT OF ECCS MODEL CHANGES PURSUANT TO THE REQUIREMENTS OF 10 CFR 50.46 By letter dated February 16, 2012 (Reference 1), the U.S. Nuclear Regulatory Commission (NRC) issued a letter to Dominion Energy Kewaunee, Inc. (DEK) requesting information pursuant to 10 CFR 50.54(f). Specifically, the letter required DEK to provide information regarding the effect of fuel pellet thermal conductivity degradation (TCD) on peak cladding temperature (PCT) calculated with the Westinghouse Electric Company (Westinghouse) realistic emergency core cooling system (ECCS) evaluation model (EM) employed for the Large Break Loss of Coolant Accident (LBLOCA) analysis for Kewaunee Power Station (KPS). The letter required that DEK provide information on KPS regarding the effect of a potentially significant error, as defined in 10 CFR 50.46(a)(3)(i), associated with TCD and the estimated effect on PCT. The purpose of the request was to ensure continued compliance with the PCT acceptance criterion promulgated in 10 CFR 50.46(b)(1).
The NRC required that DEK address the following specific issues within 30 days of the date of the information request:
- 1) An estimation of the effect of the thermal conductivity degradation error on the peak fuel cladding temperature calculation for the emergency core cooling system evaluations at the Kewaunee Power Station.
- 2) A description of the methodology and assumptions used to determine the estimates. This description shall include consideration of experimental data relevant to thermal conductivity degradation and specific information regarding any computer code model changes which were necessary to address these data.
In support of the DEK response, Westinghouse has submitted, directly to the NRC in Reference 2, a description of the methodology and assumptions used to determine the estimated PCT impact due to TCD. Reference 2 includes consideration of experimental data relevant to thermal conductivity degradation and specific information regarding
Serial No.12-100 Response to 10 CFR 50.54(f) Request Page 2 of 5 computer code and model changes that were necessary to address the issues. The LBLOCA assessment for KPS uses the Westinghouse methodology in Reference 2.
Regarding NRC issue #1, Attachments 1 and 2 to this letter identify plant-specific assumptions for peaking factor burndown and the estimated PCT effect for the Blowdown, Reflood 1, and Reflood 2 phases of the KPS LBLOCA analysis. Attachment 1 provides information regarding the evaluation to determine the estimated PCT effects of fuel pellet TCD and peaking factor burndown, as well as the PCT effect due to design input changes. The two assessments are coupled via the plant-specific evaluation using the methodology described in Reference 2. Attachment 2 documents the impact of the estimated PCT effects for the evaluation of burnup effects due to TCD and peaking factor burndown and the design input changes on the KPS LBLOCA analysis of record results. Revised LBLOCA PCT margin utilization sheets are included in .
The current KPS LBLOCA analysis has a licensing basis PCT of 20450 F. The estimated impact on the KPS LBLOCA analysis from fuel pellet TCD is 0°F for Blowdown, 15°F for Reflood 1, and 50°F for Reflood 2 for 10 CFR 50.46 reporting purposes. The estimated impact on the KPS LBLOCA analysis from peaking factor margin was determined to be -35°F for Blowdown, -40'F for Reflood 1, and -1 150 F for Reflood 2 for 10 CFR 50.46 reporting purposes. Attachment 2 documents a new licensing basis LBLOCA PCT of 1980 0 F, which is less than the regulatory limit of 2200 0 F. After consideration of fuel pellet TCD, KPS continues to demonstrate compliance with 10 CFR 50.46(b)(1).
Evaluation of 10 CFR 50.46 Reporting The maximum estimated impact on the KPS LBLOCA EM from fuel pellet TCD is +50°F for Reflood 2. The maximum estimated impact on the KPS LBLOCA EM from peaking factor margin is -1 15 0F for Reflood 2. In addition, the current LBLOCA PCT rackup includes a +1 0°F PCT change from a HOTSPOT Fuel Relocation Error (see Attachment 2, Item A.5 in the rackup tables). While unrelated to the changes described in this report, this error is included in the determination of whether the sum of the absolute values of LBLOCA PCT changes is significant. Since the sum of the absolute magnitude of the respective changes is greater than 50 0 F, the changes represent a significant change in PCT as defined in 10 CFR 50.46(a)(3)(i).
10 CFR 50.46(a)(3)(ii) requires the licensee to provide a report within 30 days, including a proposed schedule for providing a reanalysis or taking other action as may be needed to show compliance with 10 CFR 50.46. DEK has reviewed the information provided by Westinghouse and determined that the adjusted LBLOCA PCT values and the manner in which they were derived continue to comply with the requirements of 10 CFR 50.46.
DEK has evaluated the requirement for reanalysis specified in 10 CFR 50.46(a)(3)(ii) and hereby proposes the following schedule for reanalysis.
Serial No.12-100 Response to 10 CFR 50.54(f) Request Page 3 of 5 Before December 15, 2016, DEK will submit to the NRC for review and approval a LBLOCA analysis that applies NRC-approved methods that include the effects of fuel TCD. The date for the analysis submittal is based on the following milestones, which must be completed in order to perform a revised licensing basis LBLOCA analysis with an NRC-approved ECCS EM that explicitly accounts for TCD:
- 1) NRC approval of a fuel performance analysis methodology that includes the effects of TCD. The new methodology for developing inputs to the LBLOCA EM would replace the current KPS licensing basis methodology in WCAP-15063-P-A, Revision 1 (Reference 3), which is referenced in Section 14.3.3.2 of the KPS Updated Safety Analysis Report (USAR).
- 2) NRC approval of a LBLOCA EM that includes the effects of TCD and accommodates the ongoing 10 CFR 50.46(c) rulemaking process. The new methodology would replace the current licensing basis methodologies in WCAP-12945-P-A (Reference 4) and WCAP-14449-P-A (Reference 5), which are referenced in Section 14.3.3.2 of the KPS USAR.
This information satisfies the reporting requirements of 10 CFR 50.46(a)(3)(ii).
If you have questions or require additional information, please feel free to contact Mr.
Craig Sly at 804-273-2784.
Very truly yours, Site Vi President - Kewaunee Power Station STATE OF WISCONSIN )
)
COUNTY OF KEWAUNEE )
The foregoing document was acknowledged before me, in and for the County and State aforesaid, today by A. J. Jordan, who is Site Vice President Kewaunee Power Station of Dominion Energy Kewaunee, Inc. He has affirmed before me that he is duly authorized to execute and file the foregoing document in behalf of that Company, and the statements in the document are true to the best of his knowledge and belief.
Acknowledged before me this /Q-.*( day of /A7*? i- , 2012.
My Commission expires: I)-,,* AI, .-.2 7. I/
Notary Public NOREEN WENBORNE Notary Public State of Wisconsin IL __ __ __
- Serial No.12-100 Response to 10 CFR 50.54(f) Request Page 4 of 5 Attachments:
- 1. Information Regarding Evaluation of Thermal Conductivity Degradation
- 2. 10 CFR 50.46 Report and Peak Cladding Temperature Rackup Sheets
References:
- 1. Letter from Michele G. Evans, U.S. Nuclear Regulatory Commission, to David A.
Heacock, Dominion Energy Kewaunee, "Kewaunee Power Station - Information Request Pursuant to 50.54(f) Related to the Estimated Effect on Peak Cladding Temperature Resulting from Thermal Conductivity Degradation in the Westinghouse Furnished Realistic Emergency Core Cooling System Evaluation (TAC No. M99899)," February 16, 2012. [ADAMS Accession No. ML120410195]
- 2. Letter from J. A. Gresham (Westinghouse) to USNRC Document Control Desk, "Westinghouse Input Supporting Licensee Response to NRC 10 CFR 50.54(f)
Letter Regarding Nuclear Fuel Thermal Conductivity Degradation (Proprietary/Non-Proprietary)," LTR-NRC-12-27, March 7, 2012.
- 3. WCAP-15063-P-A, Revision 1 with Errata (Proprietary), Foster J. P., et al.,
"Westinghouse Improved Performance Analysis and Design Model (PAD 4.0),"
July 2000.
- 4. WCAP-12945-P-A, Volume 1, Revision 2, and Volumes 2 - 5, Revision 1 (Proprietary), Bajorek, S. M., et al., "Code Qualification Document for Best Estimate LOCA Analysis," March 1998.
- 5. WCAP-14449-P-A, Revision 1 (Proprietary), Dederer, S. I., "Application of Best Estimate Large Break LOCA Methodology to Westinghouse PWRs with Upper Plenum Injection," October 1999.
WCAP-1 5063-P-A, Revision 1 with Errata (Proprietary), Foster J. P., et al.,
"Westinghouse Improved Performance Analysis and Design Model (PAD 4.0),"
July 2000.
Commitments made by this letter:
Before December 15, 2016, DEK will submit to the NRC for review and approval a LBLOCA analysis that applies an NRC-approved ECCS Evaluation Model that includes the effects of fuel thermal conductivity degradation.
Serial No.12-100 Response to 10 CFR 50.54(f) Request Page 5 of 5 cc: Director, Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission One White Flint North, Mail Stop 13-H16M 11555 Rockville Pike Rockville, MD 20852-2738 Regional Administrator, Region III U. S. Nuclear Regulatory Commission 2443 Warrenville Road Suite 210 Lisle, IL 60532-4352 Mr. Karl D. Feintuch Project Manager U.S. Nuclear Regulatory Commission One White Flint North, Mail Stop 08-H4A 11555 Rockville Pike Rockville, MD 20852-2738 NRC Senior Resident Inspector Kewaunee Power Station
Serial No.12-100 ATTACHMENT 1 RESPONSE TO INFORMATION REQUEST PURSUANT TO 10 CFR 50.54(f)
RELATED TO THE ESTIMATED EFFECT ON PEAK CLADDING TEMPERATURE RESULTING FROM THERMAL CONDUCTIVITY DEGRADATION IN THE WESTINGHOUSE FURNISHED REALISTIC EMERGENCY CORE COOLING SYSTEM (ECCS) EVALUATION AND 30-DAY REPORT OF ECCS MODEL CHANGES PURSUANT TO THE REQUIREMENTS OF 10 CFR 50.46 Information Regarding Evaluation of Thermal Conductivity Degradation KEWAUNEE POWER STATION DOMINION ENERGY KEWAUNEE, INC.
Serial No.12-100 Attachment 1 Page 1 of 3 Information Regarding Evaluation of Thermal Conductivity Degradation
1. Background
The Nuclear Regulatory Commission (NRC) approved 1999 Westinghouse Best Estimate Large Break LOCA Evaluation Model, Application to PWRs with Upper Plenum Injection (References 1 and 2), is based on the PAD 3.4 fuel performance code (Reference 3). Upon NRC approval of PAD 4.0 (Reference 4), its usage was extended to the 1999 Westinghouse Best Estimate Large Break LOCA Evaluation Model, Application to PWRs with Upper Plenum Injection, as reported to the NRC in Reference
- 5. PAD 4.0 was licensed without explicitly considering fuel pellet thermal conductivity degradation (TCD) with burnup. Explicit modeling of fuel pellet TCD in the fuel performance code leads to changes in the fuel rod design parameters beyond beginning-of-life which are input to the Large Break LOCA (LBLOCA) analysis. The effects of explicitly modeling fuel pellet TCD on the Kewaunee LBLOCA analysis have been considered due to a request from the NRC staff. Westinghouse considers the modeling of fuel pellet TCD a Non-Discretionary Change in accordance with Section 4.1.2 of WCAP-1 3451 (Reference 6).
Fuel performance data that accounts for fuel pellet TCD (using an unlicensed model) was used as input to the Kewaunee evaluation. The new PAD fuel performance data was generated with a representative model that includes explicit modeling of fuel pellet TCD. Therefore, the evaluations performed consider the fuel pellet TCD effects cited in NRC Information Notice 2011-21 (Reference 7).
- 2. Large Break LOCA Input Parameters The evaluation of analysis design input changes with respect to plant operation considered the following input parameter changes to the LBLOCA analysis:
- Reduction in full-power FDH (hot rod average power, including uncertainties) from 1.8 (analysis of record value) to 1.7 (current COLR limit)
- Corresponding reduction in hot assembly average power (including uncertainties)
The evaluation of fuel pellet thermal conductivity degradation considered the following input parameter changes to the LBLOCA analysis:
- Peaking factor burndown shown in Table 1
Serial No.12-100 Attachment 1 Page 2 of 3
- 3. Large Break LOCA Evaluation Description The evaluation method described in Reference 8 for the calculation of the margin PCT was used to assess the impact of the reduction in maximum peaking factors on the Kewaunee LBLOCA analysis. Specifically, the reference transient was re-run at beginning-of-life conditions with the reduced peaking factors, and a PCT benefit was assigned based on the plant-specific run results.
The evaluation method discussed in Reference 8 was used to determine the estimated effect of fuel pellet TCD and peaking factor burndown.
- 4. Large Break LOCA Evaluation Results The results of the evaluation of fuel pellet thermal conductivity degradation and peaking factor burndown as well as the design input changes are presented in Table 2.
- 5. References
- 1. WCAP-12945-P-A, Volume 1, Revision 2, and Volumes 2 through 5, Revision 1, "Code Qualification Document for Best Estimate LOCA Analysis," March 1998.
- 2. WCAP-14449-P-A, Revision 1, "Application of Best Estimate Large Break LOCA Methodology to Westinghouse PWRs with Upper Plenum Injection," October 1999.
- 3. WCAP-10851-P-A, "Improved Fuel Performance Models for Westinghouse Fuel Rod Design and Safety Evaluations," August 1988.
- 4. WCAP-15063-P-A with Errata, Revision 1, "Westinghouse Improved Performance Analysis and Design Model (PAD 4.0)," July 2000.
- 5. LTR-NRC-01-6, "10 CFR 50.46 Annual Notification and Reporting for 2000," March 13, 2001.
- 6. WCAP-13451, "Westinghouse Methodology for Implementation of 10 CFR 50.46 Reporting," October 1992.
- 7. NRC Information Notice 2011-21, "Realistic Emergency Core Cooling System Evaluation Model Effects Resulting From Nuclear Fuel Thermal Conductivity Degradation," December 13, 2011.
- 8. LTR-NRC-12-27, "Westinghouse Input Supporting Licensee Response to NRC 10 CFR 50.54(f) Letter Regarding Nuclear Fuel Thermal Conductivity Degradation (Proprietary/Non-Proprietary)," March 7, 2012.
Serial No.12-100 Attachment 1 Page 3 of 3 Table 1 Peaking Factor Burndown Considered in the Evaluation of TCD Rod Burnup FQ FDH(',2)
(MWD/MTU) FQ Steady-State ransien 0 2.1 2.5 1.7 30,000 2.0 2.5 1.7 50,000 1.625 2.125 1.406 62,000 1.4 2.125 1.3 (1) Includes uncertainties.
(2) Hot assembly average power follows the same burndown, since it is a function of FDH.
Table 2 Fuel Pellet TCD and Plant Margin Evaluation Results Evaluation Blowdown Reflood 1 Reflood 2 APCT (0F) APCT (-F) APCT (-F)
TCD (including burndown) 0 15 50 Plant Peaking Factor -35 -40 -115 Margins I I _I
Serial No.12-100 ATTACHMENT 2 RESPONSE TO INFORMATION REQUEST PURSUANT TO 10 CFR 50.54(f)
RELATED TO THE ESTIMATED EFFECT ON PEAK CLADDING TEMPERATURE RESULTING FROM THERMAL CONDUCTIVITY DEGRADATION IN THE WESTINGHOUSE FURNISHED REALISTIC EMERGENCY CORE COOLING SYSTEM (ECCS) EVALUATION AND 30-DAY REPORT OF ECCS MODEL CHANGES PURSUANT TO THE REQUIREMENTS OF 10 CFR 50.46 10 CFR 50.46 Report and Peak Cladding Temperature Rackup Sheets KEWAUNEE POWER STATION DOMINION ENERGY KEWAUNEE, INC.
Serial No.12-100 Attachment 2 Page 1 of 7 Evaluation of Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown (Non-Discretionary Change)
Background
Fuel pellet thermal conductivity degradation (TCD) and peaking factor burndown were not explicitly considered in the Large Break Loss of Coolant Accident (LBLOCA)
Analysis of Record (AOR) for Kewaunee. The Nuclear Regulatory Commission (NRC) requested DEK to provide an estimated effect of TCD on the peak cladding temperature (PCT) calculation for the emergency core cooling system at Kewaunee. This change represents a Non-Discretionary Change in accordance with Section 4.1.2 of WCAP-13451 (Reference 1).
Affected Evaluation Model(s) 1999 Westinghouse Best Estimate Large Break LOCA Evaluation Model, Application to PWRs with Upper Plenum Injection (References 3 and 4)
Estimated Effect A quantitative evaluation as discussed in Reference 2 was performed to assess the effect of TCD and peaking factor burndown with other considerations of burnup on PCT and the LBLOCA analysis for Kewaunee. The evaluation concluded that the estimated PCT impact is 0°F for Blowdown, 150 F for Reflood 1, and 50'F for Reflood 2 for 10 CFR 50.46 reporting purposes. The peaking factor burndown included in the evaluation is provided in Table 1. Dominion and its vendor, Westinghouse Electric Company LLC, utilize processes which ensure that LOCA analysis input values conservatively bound the as-operated plant values for those parameters. The peaking factor burndown is conservative for the current cycle and will be validated as part of the reload design process.
Table 1: Peaking Factors Versus Rod Burnup Rod Burnup (MWD/MTU) FQ Steady-State FQ Transient( 1 F 0 2.1 2.5 1.7 30,000 2.0 2.5 1.7 50,000 1.625 2.125 1.406 62,000 1.4 2.125 1.3 (1) Includes uncertainties.
(2) Hot assembly average power follows the same burndown, since it is a function of FDH.
Serial No.12-100 Attachment 2 Page 2 of 7 References
- 1. WCAP-13451, "Westinghouse Methodology for Implementation of 10 CFR 50.46 Reporting," October 1992.
- 2. LTR-NRC-12-27, "Westinghouse Input Supporting Licensee Response to NRC 10 CFR 50.54(f) Letter Regarding Nuclear Fuel Thermal Conductivity Degradation (Proprietary/Non-Proprietary)," March 7, 2012.
- 3. WCAP-12945-P-A, Volume 1, Revision 2, and Volumes 2 through 5, Revision 1, "Code Qualification Document for Best Estimate LOCA Analysis," March 1998.
- 4. WCAP-14449-P-A, Revision 1, "Application of Best Estimate Large Break LOCA Methodology to Westinghouse PWRs with Upper Plenum Injection," October 1999.
Serial No.12-100 Attachment 2 Page 3 of 7 Evaluation of Design Input Changes With Respect to Plant Operation
Background
To demonstrate compliance with the 10 CFR 50.46(b)(1) acceptance criterion concerning peak cladding temperature (PCT) when explicitly considering fuel pellet thermal conductivity degradation (TCD) and peaking factor burndown in the Large Break Loss of Coolant Accident (LBLOCA) Analysis of Record (AOR) for Kewaunee, design input values were revised to more closely represent current plant operation.
These input changes do not constitute changes to the approved 1999 Westinghouse Best Estimate Large Break LOCA Evaluation Model, Application to PWRs with Upper Plenum Injection. The updated inputs for Kewaunee include:
" Reduction in full-power FDH (hot rod average power, including uncertainties) from 1.8 (analysis of record value) to 1.7 (current COLR limit)
- Corresponding reduction in hot assembly average power (including uncertainties)
Dominion and its vendor, Westinghouse Electric Company LLC, utilize processes which ensure that LOCA analysis input values conservatively bound the as-operated plant values for those parameters.
Affected Evaluation Model(s) 1999 Westinghouse Best Estimate Large Break LOCA Evaluation Model, Application to PWRs with Upper Plenum Injection (References 2 and 3)
Estimated Effect A quantitative evaluation as discussed in Reference 1 was performed to estimate an overall PCT change due to changes in design input parameters. The evaluation concluded that the estimated PCT impact of these analysis input changes is -35 0 F for Blowdown, -40°F for Reflood 1, and -1 15 0F for Reflood 2 for 10 CFR 50.46 reporting.
References
- 1. LTR-NRC-12-27, "Westinghouse Input Supporting Licensee Response to NRC 10 CFR 50.54(f) Letter Regarding Nuclear Fuel Thermal Conductivity Degradation (Proprietary/Non-Proprietary)," March 7, 2012.
- 2. WCAP-12945-P-A, Volume 1, Revision 2, and Volumes 2 through 5, Revision 1, "Code Qualification Document for Best Estimate LOCA Analysis," March 1998.
- 3. WCAP-14449-P-A, Revision 1, "Application of Best Estimate Large Break LOCA Methodology to Westinghouse PWRs with Upper Plenum Injection," October 1999.
Serial No.12-100 Attachment 2 Page 4 of 7 Westinghouse LOCA Peak Clad Temperature Summary for Best Estimate Large Break Plant Name: Kewaunee Power Station Utility Name: Dominion Energy Kewaunee, Inc.
Composite Analysis Information EM: UPI (1999) Analysis Date: 3/25/2002 Limiting Break Size: Split FQ: 2.5 FdH: 1.8 Fuel: 422 Vantage + SGTP (%): 10 Notes: Uprate to 1772 MWt. Effective beginning Cycle 26. Post-AOR evaluation of FdH = 1.7.
Clad Temp (OF) Notes LICENSING BASIS Analysis-Of-Record PCT 2084 PCT ASSESSMENTS (Delta PCT)
A. PRIOR ECCS MODEL ASSESSMENTS
- 1. Revised Blowdown Heatup Uncertainty Distribution 5
- 2. Spacer Grid Heat Transfer Model Inputs 5
- 3. Inconsistent Vessel Vertical Level Modeling 0
- 4. Revised Downcomer Gap Inputs -59
- 5. HOTSPOT Fuel Relocation Error 10 B. PLANNED PLANT MODIFICATION EVALUATIONS I. Design Input Changes with Respect to Plant Operation -115 (ab)
C. 2012 ECCS MODEL ASSESSMENTS
- 1. Evaluation of Pellet Thermal Conductivity Degradation and Peaking Factor Bumdown 50 (a)
D. OTHER I. None 0 LICENSING BASIS PCT + PCT ASSESSMENTS PCT = 1980 Notes:
(a) These assessments are coupled via an evaluation of bumup effects which include thermal conductivity degradation, peaking factor bumdown and design input changes.
(b) Design input changes were a reduction in FdH from 1.8 to 1.7, and a corresponding reduction in Pbar-HA.
Serial No.12-100 Attachment 2 Page 5 of 7 Westinghouse LOCA Peak Clad Temperature Summary for Best Estimate Large Break Plant Name: Kewaunee Power Station Utility Name: Dominion Energy Kewaunee, Inc.
Blowdown Analysis Information EM: UPI (1999) Analysis Date: 3/25/2002 Limiting Break Size: Split FQ: 2.5 FdH: 1.8 Fuel: 422 Vantage + SGTP (%): 10 Notes: Uprate to 1772 MWt. Effective beginning Cycle 26. Post-AOR evaluation of FdH = 1.7.
Clad Temp (OF) Notes LICENSING BASIS Analysis-Of-Record PCT 1924 PCT ASSESSMENTS (Delta PCT)
A. PRIOR ECCS MODEL ASSESSMENTS I. Revised Blowdown Heatup Uncertainty Distribution 49
- 2. Revised Downcomer Gap Inputs -3
- 3. Inconsistent Vessel Vertical Level Modeling 0
- 4. HOTSPOT Fuel Relocation Error 0 B. PLANNED PLANT MODIFICATION EVALUATIONS
- 1. Design Input Changes with Respect to Plant Operation -35 (a,b)
C. 2012 ECCS MODEL ASSESSMENTS
- 1. Evaluation of Pellet Thermal Conductivity Degradation and Peaking Factor Bumdown 0 (a)
D. OTHER
(a) These assessments are coupled via an evaluation of bumup effects which include thermal conductivity degradation, peaking factor bumdown and design input changes.
(b) Design input changes were a reduction in FdH from 1.8 to 1.7, and a corresponding reduction in Pbar-HA.
Serial No.12-100 Attachment 2 Page 6 of 7 Westinghouse LOCA Peak Clad Temperature Summary for Best Estimate Large Break Plant Name: Kewaunee Power Station Utility Name: Dominion Energy Kewaunee, Inc.
Reflood 1 Analysis Infoirmation EM: UPI (1999) Analysis Date: 3/25/2002 Limiting Break Size: Split FQ: 2.5 FdH: 1.8 Fuel: 422 Vantage + SGTP (%): 10 Notes: Uprate to 1772 MWt. Effective beginning Cycle 26. Post-AOR evaluation of FdH = 1.7.
Clad Temp (IF) Notes LICENSING BASIS Analysis-Of-Record PCT 1892 PCT ASSESSMENTS (Delta PCT)
A. PRIOR ECCS MODEL ASSESSMENTS
- 1. Revised Blowdown Heatup Uncertainty Distribution 5
- 2. Spacer Grid Heat Transfer Model Inputs 5
- 3. Inconsistent Vessel Vertical Level Modeling 0
- 4. Revised Downcomer Gap Inputs -29
- 5. HOTSPOT Fuel Relocation Error 5 B. PLANNED PLANT MODIFICATION EVALUATIONS
- 1. Design Input Changes with Respect to Plant Operation -40 (a,b)
C. 2012 ECCS MODEL ASSESSMENTS
- 1. Evaluation of Pellet Thermal Conductivity Degradation and Peaking Factor Bumdown 15 (a)
D. OTHER I. None 0 LICENSING BASIS PCT + PCT ASSESSMENTS PCT = 1853 Notes:
(a) These assessments are coupled via an evaluation of bumup effects which include thermal conductivity degradation, peaking factor bumdown and design input changes.
(b) Design input changes were a reduction in FdH from 1.8 to 1.7, and a corresponding reduction in Pbar-HA.
Serial No.12-100 Attachment 2 Page 7 of 7 Westinghouse LOCA Peak Clad Temperature Summary for Best Estimate Large Break Plant Name: Kewaunee Power Station Utility Name: Dominion Energy Kewaunee, Inc.
Reflood 2 Analysis Information EM: UPI (1999) Analysis Date: 3/25/2002 Limiting Break Size: Split FQ: 2.5 FdH: 1.8 Fuel: 422 Vantage + SGTP (%): 10 Notes: Uprate to 1772 MWt. Effective beginning Cycle 26. Post-AOR evaluation of FdH = 1.7.
Clad Temp (IF) Notes LICENSING BASIS Analysis-Of-Record PCT 2084 PCT ASSESSMENTS (Delta PCT)
A. PRIOR ECCS MODEL ASSESSMENTS
- 1. Revised Blowdown Heatup Uncertainty Distribution 5
- 2. Spacer Grid Heat Transfer Model Inputs 5
- 3. Inconsistent Vessel Vertical Level Modeling 0
- 4. Revised Downcomer Gap Inputs -59
- 5. HOTSPOT Fuel Relocation Error 10 B. PLANNED PLANT MODIFICATION EVALUATIONS
- 1. Design Input Changes with Respect to Plant Operation -115 (ab)
C. 2012 ECCS MODEL ASSESSMENTS
- 1. Evaluation of Pellet Thermal Conductivity Degradation and Peaking Factor Bumdown 50 (a)
D. OTHER
(a) These assessments are coupled via an evaluation of bumup effects which include thermal conductivity degradation, peaking factor bumdown and design input changes.
(b) Design input changes were a reduction in FdH from 1.8 to 1.7, and a corresponding reduction in Pbar-HA.