ML061810043
| ML061810043 | |
| Person / Time | |
|---|---|
| Site: | Millstone, Kewaunee, Surry, North Anna  |
| Issue date: | 06/28/2006 |
| From: | Grecheck E Dominion Resources Services |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 06-521 | |
| Download: ML061810043 (38) | |
Text
Dominion Resources Services, Inc.
5000 I h r n ~ n m n Boulevard, Glen Allen. VA 2.3060 June 28, 2006 U.S. Nuclear Regulatory Commission Attention: Document Control Desk One White Flint North 1 1555 Rockville Pike Rockville, MD 20852-2738 Serial No.06-521 NL&OSlPRW R1 Docket Nos.
50-305 50-3361423 50-3381339 50-2801281 License Nos.
DPR-43 DPR-65lN PF-49 N PF-417 D PR-32/37 DOMINION ENERGY KEWAUNEE. INC.
DOMINION NUCLEAR CONNECTICUT. INC.
VIRGINIA ELECTRIC AND POWER COMPANY KEWAUNEE POWER STATION MILLSTONE POWER STATION UNITS 2 AND 3 NORTH ANNA POWER STATION UNITS 1 AND 2 SURRY POWER STATION UNITS 1 AND 2 2005 ANNUAL REPORT OF EMERGENCY CORE COOLING SYSTEM (ECCS) MODEL CHANGES PURSUANT TO THE REQUIREMENTS OF 10 CFR 50.46 In accordance with 10 CFR 50.46(a)(3)(ii), Dominion Energy Kewaunee, Inc. (DEK),
Dominion Nuclear Connecticut, Inc. (DNC) and Virginia Electric and Power Company (Dominion) hereby submit the annual summary of changes to the emergency core cooling system (ECCS) evaluation models for Kewaunee Power Station (KPS), Millstone Power Station Units 2 and 3 (MPS 2&3), North Anna Power Station Units 1 and 2 (NAPS 1&2),
and Surry Power Station Units 1 and 2 (SPS I
&2), respectively. of this letter provides a report describing plant-specific evaluation model changes associated with the Westinghouse and AREVA Small Break Loss of Coolant Accident (SBLOCA) and Large Break Loss of Coolant Accident (LBLOCA) ECCS Evaluation Models for KPS, MPS 2&3, NAPS 1 &2, and SPS 1 &2.
Information regarding the effect of the ECCS evaluation model changes on the SBLOCA and LBLOCA analyses of record (AOR) results is provided for KPS, MPS 2&3, NAPS 1 &2, and SPS 1 &2 in Attachments 2, 3,4 and 5, respectively. Currently, the cores at NAPS 1&2 are comprised of both Westinghouse fuel and AREVA fuel.
Therefore!, there are two sets of margin utilization data for NAPS 1&2. The calculated peak cladding temperature (PCT) for the SBLOCA and LBLOCA analyses for KPS, MPS 2&3, NAPS 1 &2, and SPS 1 &2 are summarized below.
Serial Number 06-521 Docket Nos. 50-305/336/423/338/339/280/281 10 CFR 50.46 Annual Report Page 2 of 5 Kewaunee - Small break - Westinghouse Evaluation Model:
Kewaunee - Large break - Westinghouse Evaluation Model:
Millstone Unit 2 - Small break - AREVA Evaluation Model :
Millstone Unit 2 - Large break - AREVA Evaluation Model :
Millstone Unit 3 - Small break - Westinghouse Evaluation Model :
Millstone Unit 3 - Large break - Westinghouse Evaluation Model :
North Anna Unit 1 - Small break - Westinghouse Evaluation Model :
North Anna Unit 1 - Large break - Westinghouse Evaluation Model :
North Anna Unit 1 - Small break - AREVA Evaluation Model :
North Anna Unit 1 - Large break - AREVA Evaluation Model :
North Anna Unit 2 - Small break - Westinghouse Evaluation Model :
North Anna Unit 2 - Large break - Westinghouse Evaluation Model :
North Anna Unit 2 - Small break - AREVA Evaluation Model :
North Anna Unit 2 - Large break - AREVA Evaluation Model :
Surry Units 1 and 2 - Small break - Westinghouse Evaluation Model :
Surry Units 1 and 2 - Large break - Westinghouse Evaluation Model :
The LOCA results for KPS, MPS 2&3, NAPS 1&2, and SPS 1&2 are confirmed to have sufficient margin to the 2200°F limit for PCT specified in 10 CFR 50.46. Based on the evaluatio~n of this information and the resulting changes in the applicable licensing basis PC'T results, no further action is required to demonstrate compliance with the 10 CFR 50.416 requirements. However, as indicated in a letter dated April 20, 2006 (Serial No.06-312), reanalysis of the LBLOCA, utilizing the NRC-approved Westinghouse ASTRUM methodology (WCAP-16009-P-A, January 2005), for Surry Units 1 and 2 is scheduled to be complete by September 30, 2006.
In a letter dated February 27, 2006, DEK submitted the annual operating report for KPS which contained the 10 CFR 50.46 annual report for 2004. Therefore, the (2005) information contained in Attachments 1 and 2 is the second report submitted this year for KPS.
If you have any questions regarding this submittal, please contact Mr. Paul R.
Willoug hby at (804) 273-3572.
Very truly yours, Eugene S. Grecheck Vice President - Nuclear Support Services
Serial Number 06-521 Docket Nos. 50-305/336/423/338/339/280/281 10 CFR 50.46 Annual Report Page 3 of 5 Commitments made in this letter:
No new commitments are being made in this letter; however, in a letter dated April 20, 2006 (Serial No. 06-31 2), Dominion committed to completion of the LBLOCA reanalysis for Surry Units 1 and 2 by September 30, 2006.
Attachments: (5)
Report of Changes in Westinghouse and AREVA ECCS Evaluation Models.
2005 Annual Reporting of 10 CFR 50.46 Margin Utilization - Kewaunee Power Station.
2005 Annual Reporting of 10 CFR 50.46 Margin Utilization - Millstone Power Station Units 2 and 3.
2005 Annual Reporting of 10 CFR 50.46 Margin Utilization - North Anna Power Station Units 1 and 2.
2005 Annual Reporting of 10 CFR 50.46 Margin Utilization - Surry Power Station Units 1 and 2.
Serial Number 06-521 Docket Nos. 50-305/336/423/338/339/280/281 10 CFR 50.46 Annual Report Page 4 of 5 cc:
U.S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, Pennsylvania 19406-1 41 5 U.S. Nuclear Regulatory Region II Sam Nunn Atlanta Federal Center 61 Forsyth Street, SW Suite 23T85 Atlanta, Georgia 30303 U.S. Nuclear Regulatory Commission Region Ill 24143 Warrenville Road Suite 21 0 Lisle, Illinois 60532-4352 Mr. S. C. Burton NFlC Senior Resident lnspector Kewaunee Power Station Mr. S. M. Schneider NFlC Senior Resident lnspector Millstone Power Station Mr. J. T. Reece NFlC Senior Resident lnspector North Anna Power Station Mr. N. P. Garrett NRC Senior Resident lnspector Surry Power Station Mr. D. H. Jaffe NFlC Project Manager - Kewaunee Power Station U. S. Nuclear Regulatory Commission One White Flint North 1 1 !555 Rockville Pike Mali1 Stop 0-7-D-1 Rockville, Maryland 20852-2738
Serial Number 06-521 Docket Nos. 50-305/336/423/338/339/280/281 10 CFR 50.46 Annual Report Page 5 of 5 Mr,. V. Nerses NFlC Senior Project Manager - Power Station U. S. Nuclear Regulatory Commission One White Flint North 1 1 !555 Rockville Pike Mali1 Stop 8C2 Rockville, Maryland 20852-2738 Mr. S. R. Monarque NFlC Project Manager - North Anna Power Station U. S. Nuclear Regulatory Commission One White Flint North 1 1 !555 Rockville Pike Mail Stop 8-H 1 2 Rockville, Maryland 20852-2738 Mr. S. P. Lingam NFlC Project Manager - Surry Power Station U. S. Nuclear Regulatory Commission One White Flint North 1 1 !555 Rockville Pike Mad Stop 8 G9A Rockville, Maryland 20852-2738
Serial Number 06-521 Docket Nos. 50-305/336/423/338/339/280/281 ATTACHMENT 1 2005 ANNUAL REPORT OF EMERGENCY CORE COOLING SYSTEM (ECCS) MODEL CHANGES PURSUANT TO THE REQUIREMENTS OF 10 CFR 50.46 REPORT OF CHANGES IN DOMINION ENERGY KEWAUNEE, INC.
DOMINION NUCLEAR CONNECTICUT, INC.
VIRGINIA ELECTRIC AND POWER COMPANY KEWAUNEE POWER STATION MILLSTONE POWER STATION UNITS 2 AND 3 NORTH ANNA POWER STATION UNITS 1 AND 2 SURRY POWER STATION UNITS 1 AND 2
Serial Number 06-521 Docket Nos. 50-305133614231338133912801281 1 0 CFR 50.46 Annual Report Page 1 of 5 REPORT OF CHANGES IN WESTINGHOUSE AND AREVA ECCS EVALUATION MODELS Generic Westinahouse PCT Assessments with No lm~act on PCT Westingh~ouse identified the following errors and changes applicable to the NOTRUMP Small Break Loss of Coolant Accident (SBLOCA) and BASH Large Break Loss of Coolant Accident (LBLOCA) evaluation models. Each was evaluated to have a PCT impact of 0°F. Since these items have no impact on PCT, they will not be shown on the PCT Margin Utilization sheets provided in Attachments 2 through 5.
- a.
Pressurizer Fluid Volumes (BASHINOTRUMP)
- b.
Lower Guide Tube Assembly Weight (BASHINOTRUMP)
- c.
Discrepancy in NOTRUMP RWST Draindown Calculation (NOTRUMP)
- d.
General Code Maintenance (BASHINOTRUMP)
Westingh~ouse identified the following errors and changes in the 1999 Westinghouse Best Esti~mate LBLOCA evaluation model with application to PWRs with upper plenum injection. This evaluation model is utilized at Kewaunee Power Station. Each was evaluated to have a PCT impact of 0°F. Since these items have no impact on PCT, they will not b'e shown on the PCT Margin Utilization sheets applicable to Kewaunee which are provided in Attachment 2.
Revised Iteration Algorithm for Calculating the Average Fuel Temperature Pellet Radial Profile Option Improved Automation of End of Blowdown Time General Code Maintenance Thermodynamic Properties from THERMO Pressurizer Fluid Volumes Vessel Unheated Conductor Noding Level Boundary Selection Containment Relative Humidity Assumption The following summarizes the plant specific PCT assessments since the previous annual reports.
Kewaunee Power Station
- 1.
No changes or errors were identified in the NOTRUMP SBLOCA analysis.
- 2.
Westinghouse identified a discrepancy in the Spacer Grid Heat Transfer Model Inputs whereby the spacer grid blocked area ratio and open area fraction inputs were revised or corrected, but were not evaluated for impact on the LBLOCA
Serial Number 06-521 Docket Nos. 50-305/336/423/338/339/280/281 10 CFR 50.46 Annual Report Page 2 of 5 analysis. Using revised values, a plant-specific evaluation was performed and de'termined the PCT effect of the blocked area ratio and open area fraction differences to be APCT=+5OF.
Westinghouse identified a discrepancy during the course of a 1999 Westinghouse Best Estimate LBLOCA Evaluation Model analysis whereby some prior analyses failed to model the diffuser plate. As such, the total liquid volume in the lower plenum is overestimated and the total metal mass in the lower plenum is underestimated. The pressure drop calculated through the vessel did account for the loss due to the diffuser plate. A plant specific evaluation was co~mpleted for the affected plants. This evaluation concluded that there is no significant impact on the LBLOCA analysis results due to the small increase in lower plenum liquid volume and small decrease in lower plenum metal mass modeled, leading to an estimated impact on PCT of APCT=O°F. Since this item has no impact on PCT, it will not be shown on the LBLOCA PCT Margin Utilization sheet applicable to Kewaunee which is provided in Attachment 2.
- 4.
Westinghouse identified a discrepancy during the course of a 1999 Westinghouse Best Estimate LBLOCA Evaluation Model analysis whereby the momentum area specified at the top of the downcomer in some prior analyses is inckonsistent with the analysis input guidelines. An evaluation was completed to estimate the effect of these differences on typical LBLOCA analysis results for plants with Upper Plenum Injection. This evaluation concluded that there is no siginificant impact on the LBLOCA analysis results due to the modeling of the momentum area at the top of the downcomer, leading to an estimated impact on PC:T of APCT=O°F. Since this item has no impact on PCT, it will not be shown on the LBLOCA PCT Margin Utilization sheet applicable to Kewaunee which is provided in Attachment 2.
Millstone Power Station Units 2 and 3
- 1.
No changes or errors were identified in the SBLOCA or LBLOCA ECCS eviduation models for Millstone Unit 2.
- 2.
No changes or errors were identified in the Westinghouse SBLOCA or LBLOCA EC:CS evaluation models for Millstone Unit 3.
- 3.
Westinghouse evaluated the impact of a planned plant modification to the Millstone Unit 3 charging pump alternate miniflow line, which required a revision to the charginglsafety injection (CHGISI) flowrates. Westinghouse evaluated the impact of the revised CHGISI flows on PCT. The evaluation indicated that the revised CHGISI flows had a negligible impact on both the SBLOCA and LBLOCA
Serial Number 06-521 Docket Nos. 50-305/336/423/338/339/280/281 10 CFR 50.46 Annual Report Page 3 of 5 Analyses of Record (AOR). As such, the impact of this modification will be tracked as APCT=O°F for both SBLOCA and LBLOCA.
North Anna Power Station Units 1 and 2
- 1.
No1 changes or errors were identified in the Westinghouse SBLOCA or LBLOCA ECCS evaluation models for North Anna Units 1 and 2.
- 2.
No changes or errors were identified in the AREVA SBLOCA evaluation model for North Anna Units 1 and 2.
- 3.
AFlEVA evaluated the following changes and errors in the Realistic LBLOCA evisluation model for North Anna Units 1 and 2:
I RL-BLOCA Choked Flow Disposition I -26°F 1
22°F NAPS1 APCT NAPS2 APCT These items were previously reported to the NRC in letter Serial RL-BLOCA Changes in Uncertainty Parameters Advanced Mark-BW Top Nozzle Modification dated April 20, 2006 to meet the 30-day reporting requirements of 10 CFR 50.46 (a)(3)(ii)-
Surrv Power Station Units 1 and 2 10°F 65°F
- 1.
Dominion quantified the impact on the SBLOCA PCT resulting from the implementation of the Westinghouse Integral Fuel Burnable Absorber (IFBA) fuel product. The current SBLOCA analysis for Surry Units 1 and 2 was pe,rformed using the Westinghouse NOTRUMP evaluation model. For SBLOCA, IFBA need not be explicitly analyzed due to the insignificant difference between IFBA and non-IFBA PCTs. However, the use of annular pellets at the ends of the fuel rods does have a small impact on the SBLOCA analyses. Westinghouse has quantified a generic 10°F PCT penalty to accommodate the impact of an~nular pellets.
10°F 65°F
Serial Number 06-521 Docket Nos. 50-305/336/423/338/339/280/281 10 CFR 50.46 Annual Report Page 4 of 5
- 2.
Dominion quantified Surry-specific sensitivities to assess the PCT impact on the I PAD 4.0 Initial Pellet Temperatures I
-122°F Surry units 1 and 2 BASH LBLOCA results for the following items:
I Removal of Part Length CRDMs I
-66°F LOCBART ZIRLOTM Cladding Specific Heat Model Error Pressurizer Surge Line Piping Schedule Reconciliation SPS1 & 2 APCT 1 6°F These items were previously reported to the NRC in letter Serial No.05-383, dated July 7, 2005 to meet the 30-day reporting requirements of 10 CFR 50.46 (a)(3)(ii).
- 3.
Dominion quantified Surry-specific sensitivities to assess the PCT impact on the I Revised Containment Free Volume Surry units 1 and 2 BASH LBLOCA results for the following items:
I PAD 4.0 Initial Pellet Temperatures I
-11°F 7
Revised Containment Heat Sink Input Revised Containment Spray Flowrate I LOCBART Fluid Property Logic Issue - Augmented I 10°F SPS1 & 2 APCT 1 13°F
-1 7°F Thle -1 1°F PCT assessment for the PAD 4.0 Initial Pellet Temperatures is a revised value from the PCT assessment of -1 22°F which was previously reported as indicated in Item 2 above.
These items were previously reported to the NRC in letter Serial No.05-828, dated January 3, 2006 to meet the 30-day reporting requirements of 10 CFR 50.46 (a)(3)(ii).
Serial Number 06-521 Docket Nos. 50-305/336/423/338/339/280/281 1 0 CFR 50.46 Annual Report Page 5 of 5 Daminion quantified the impact on the LBLOCA PCT resulting from the implementation of the Westinghouse Integral Fuel Burnable Absorber (IFBA) fuel product for the following items:
I LOCBART Fluid Property Logic Issue - Augmented I
-10°F I Wlestinghouse IFBA Fuel Product Implementation 1
These items were previously reported to the NRC in letter Serial No. 06-31 2, dated April 20, 2006 to meet the 30-day reporting requirements of 10 CFR 50.46 (a)(3)(ii).
SPSI & 2 APCT 41 OF Conclusion Based on the information contained in Attachments 2 through 5, the LOCA results for Kewaunee Power Station, Millstone Power Station Units 2 and 3, North Anna Power Station Units 1 and 2, and Surry Power Station Units 1 and 2 are confirmed to have sufficient margin to the 2200°F limit of 10 CFR 50.46. Based upon our evaluation of this information and the associated changes in the applicable licensing basis PCT results, no further action is required to demonstrate compliance with the 10 CFR 50.46 requirements. Reporting of this information is required per 10 CFR 50.46(a)(3)(ii),
which obligates each licensee to report the effect upon calculated temperature of any change or error in evaluation models or their application on an annual basis.
This information satisfies the 2005 annual reporting requirements of 10 CFR 50.46(a)(:3)(ii). In addition, no reanalysis or other actions are necessary to demonstrate compliance with 10 CFR 50.46 requirements.
Serial Number 06-521 Docket No. 50-305 ATTACHMENT 2 2005 ANNUAL REPORT OF EMERGENCY CORE COOLING SYSTEM (ECCS) MODEL CHANGES PURSUANT TO THE REQUIREMENTS OF 10 CFR 50.46 21005 ANNUAL REPORTING OF 10 CFR 50.46 MARGIN UTILIZATION DOMINION ENERGY KEWAUNEE, INC.
KEWAUNEE POWER STATION
Serial Number 06-521 Docket No. 50-305 10 CFR 50.46 Annual Report Page 1 of 2 10 CFR 50.46 MARGIN UTILIZATION - SMALL BREAK LOCA Plant Name:
Kewaunee Power Station Utility Name:
Dominion Energy Kewaunee, Inc.
Analvsis Information EM:
NOTRUMP Limiting Break Size:
3 Inch CL, High Tav Analysis Date:
0511 4/02 Vendor:
Westing house FQ:
2.5 FdH:
1.8 Fuel:
422 Vantage +
SGTP(%):
10 Notes:
Uprate to 1772 MWt. Effective beginning Cycle 26 Clad T e m ~
(OF)
Notes LICENSING BASIS Analysis of Record PCT 1030 (1)
A.
Prior ECCS Model Assessments
- 1.
NOTRUMP Bubble RiseIDrift Flux Model Inconsistency 35 (2)
Corrections B.
Planned Plant Modification Evaluations
- 1.
None C.
2005 ECCS Model Assessments
- 1.
None D.
Otlher
- 1.
None LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
1065 NOTES:
{I)
Transition cycles containing FRA-ANP fuel are bounded by the analysis for a full core of Westinghouse 422+ fuel.
(2)
The accumulation of changes for these items (sum of absolute magnitudes) since the last 30-day report or reanalysis is less than or equal to 50°F and is not significant, as defined in 10 CFR 50.46(a)(3)(i).
Serial Number 06-521 Docket No. 50-305 10 CFR 50.46 Annual Report Page 2 of 2 10 CFR 50.46 MARGIN UTILIZATION - LARGE BREAK LOCA Plant Narne:
Kewaunee Power Station Utility Name:
Dominion Energy Kewaunee, Inc.
Analvsis Information EM:
U PI (1 999)
Limiting Break Size:
Split Analysis Date:
03/25/02 Vendor:
Westinghouse FQ:
2.5 FdH:
1.8 Fuel:
422 Vantage +
SGTP(%):
10 Notes:
Uprate to 1772 MWt. Effective beginning Cycle 26 Clad T e m ~
(OF)
Notes LICENSING BASIS Analysis of Record PCT 2084 (1)
A.
Prior ECCS Model Assessments
- 1.
Revised Blowdown Heatup Uncertainty Distribution 5
(2)
B.
Planned Plant Modification Evaluations
- 1.
None C.
2005 ECCS Model Assessments
- 1.
Spacer Grid Heat Transfer Model Inputs D.
Otlher
- 1.
None LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
2094 Notes:
{I)
Transition cycles containing FRA-ANP fuel are bounded by the analysis for a full core of Westinghouse 422+ fuel.
(2)
Thle accumulation of changes for these items (sum of absolute magnitudes) since the last 30-day report or reanalysis is less than or equal to 50°F and is not significant, as defined in 10 CFR 50.46(a)(3)(i).
Serial Number 06-521 Docket Nos. 50-3361423 ATTACHMENT 3 2005 ANNUAL REPORT OF EMERGENCY CORE COOLING SYSTEM (ECCS) MODEL CHANGES PURSUANT TO THE REQUIREMENTS OF 10 CFR 50.46 2005 ANNUAL REPORTING OF 10 CFR 50.46 MARGIN UTILIZATION DOMINION NUCLEAR CONNECTICUT, INC.
MILLSTONE POWER STATION UNITS 2 AND 3
Serial Number 06-521 Docket Nos. 50-3361423 10 CFR 50.46 Annual Report Page 1 of 5 10 CFR 50.46 MARGIN UTILIZATION - SMALL BREAK LOCA Plant Name:
Millstone Power Station, Unit 2 Utility Name:
Dominion Nuclear Connecticut, Inc.
Analvsis Information EM:
PWR Small Break LOCA, Limiting Break Size:
0.08 rt' S-RELAP5 Based Analysis Date:
01 102 Vendor:
AREVA Peak Linear Power:15.1 kWlft Notes:
None Clad T e m ~
(OF)
Notes LICENSING BASIS Analysis of Record PCT 1941 (11 PCT ASSESSMENTS (Delta PCT)
A.
Prior ECCS Model Assessments
- 1.
Decay Heat Model Error
- 2.
Revised SBLOCA Guideline B.
Planned Plant Modification Evaluations
- 1.
None C.
2005 ECCS Model Assessments
- 1.
None D.
Otlher
- 1.
None LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
1808 NOTES:
{I)
New Analysis of Record using S-RELAP5 based methodology.
(2)
Assessment of this change resulted in a APCT = +66OF. FRA-ANP provided this assessment for information. The +66OF assessment does not apply since the current An'alysis of Record incorporates the revised SBLOCA guideline.
(3)
Thle accumulation of changes for these items (sum of absolute magnitudes) since the last 30-day report or reanalysis is less than or equal to 50°F and is not significant, as defined in 10 CFR 50.46(a)(3)(i).
Serial Number 06-521 Docket Nos. 50-3361423 10 CFR 50.46 Annual Report Page 2 of 5 10 CFR 50.46 MARGIN UTILIZATION - LARGE BREAK LOCA Plant Name:
Millstone Power Station, Unit 2 Utility Name:
Dominion Nuclear Connecticut, Inc.
Analvsis Information EM:
SEMIPW R-98 Limiting Break Size:
1.0 DECLG Analysis Date:
1 1/98 Vendor:
AREVA Peak Linear Power:I 5.1 kW/ft Notes:
None Clad Temr, ( O F )
Notes LICENSING BASIS Analysis of Record PCT PCT ASSESSMENTS (Delta PCT)
A.
Prior ECCS Model Assessments Corrected Corrosion Enhancement Factor ICECON Coding Errors Setting RFPAC Fuel Temperatures at Start of Reflood SISPNCHIujun98 Code Error Error in Flow Blockage Model in TOODEE2 Change in TOODEE2-Calculation of QMAX Change in Gadolinia Modeling PW R LBLOCA Split Break Modeling TEOBY Calculation Error Inappropriate Heat Transfer in TOODEE2 End-of-Bypass Prediction by TEOBY R4SS Overwrite of Junction lnertia lncorrect Junction lnertia Multipliers Errors Discovered During RODEX2 V&V Error in Broken Loop SG Tube Exit Junction Inertia RFPAC Refill and Reflood Calculation Code Errors lncorrect Pump Junction Area Used in RELAP4 Error in TOODEE2 Clad Thermal Expansion Accumulator Line Loss Error Inconsistent Loss Coefficients Used for Robinson LBLOCA Pump Head Adjustment for Pressure Balance Initialization B.
Planned Plant Modification Evaluations
- 1.
None C.
2005 ECCS Model Assessments
- 1.
None D.
Otlher
- 1.
None LICENSING BASIS PCT + PCT ASSESSMENTS PCT 1823
Serial Number 06-521 Docket Nos. 50-3361423 1 0 CFR 50.46 Annual Report Page 3 of 5 Notes:
(1)
The accumulation of changes for these items (sum of absolute magnitudes) since the last 30-day report or reanalysis is less than or equal to 50°F and is not significant, as defined in 10 CFR 50.46(a)(3)(i).
Serial Number 06-521 Docket Nos. 50-3361423 10 CFR 50.46 Annual Report Page 4 of 5 10 CFR 50.46 MARGIN UTILIZATION - SMALL BREAK LOCA Plant Na~me:
Millstone Power Station, Unit 3 Utilitv Name:
Dominion Nuclear Connecticut, Inc.
Analvsis Information EM:
NOTRUMP Limiting Break Size: 3 Inches Analysis Date:
04/04 Vendor:
Westing house FQ:
2.6 FAH :
1.7 Fuel:
RFNVantage 5H SGTP (%):
10 Notes:
None Clad T e m ~
(OF)
Notes LICENSING BASIS Analysis of Record PCT PCT ASSESSMENTS (Delta PCT)
A.
Prior ECCS Model Assessments
- 1.
NOTRUMP Bubble Rise / Drift Flux Model Inconsistency Corrections B.
Planned Plant Modification Evaluations
- 1.
CHGISI Alternate MiniFlow C.
2005 ECCS Model Assessments
- 1.
None D.
Otlher
- 1.
None LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
1009 Notes:
{I)
Thle SBLOCA was reanalyzed in 2001 using NOTRUMP with the COSl colidensation model. The reanalysis did not become the Analysis of Record (AOR) until 2004.
(2)
Thiis error was identified by Westinghouse in 2003. It is applied to the 2004 ECCS Model Assessments consistent with the AOR date.
(3)
The accumulation of changes for these items (sum of absolute magnitudes) since the last 30-day report or reanalysis is less than or equal to 50°F and is not significant, as defined in 10 CFR 50.46(a)(3)(i).
Serial Number 06-521 Docket Nos. 50-3361423 10 CFR 50.46 Annual Report Page 5 of 5 10 '
Plant Na~me:
CFR 50.46 MARGIN UTILIZATION - LARGE BREAK LOCA Millstone Power Station, Unit 3 Utility Name:
Dominion Nuclear Connecticut, Inc.
Analvsis Information EM:
BASH Limiting Break Size: Cd=0.6 Analysis Date:
08/90 Vendor:
Westing house FQ:
2.6 FAH:
1.7 Fuel:
Vantage 5H SGTP (%):
10 Notes:
VHWRFA Clad T e m ~
( O F )
Notes LICENSING BASIS Analysis of Record PCT 1974 PCT ASSESSMENTS (Delta PCT)
A.
Priior ECCS Model Assessments
- 1.
None B.
Planned Plant Modification Evaluations
- 1.
CHG/SI Alternate MiniFlow C.
20105 ECCS Model Assessments
- 1.
None D.
Otlher
- 1.
Rebaseline of AOR LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
2004 Notes:
{I)
The accumulation of changes for these items (sum of absolute magnitudes) since the last 30-day report or reanalysis is less than or equal to 50°F and is not significant, as defined in 10 CFR 50.46(a)(3)(i).
Serial Number 06-521 Docket Nos. 50-3381339 ATTACHMENT 4 2005 ANNUAL REPORT OF EMERGENCY CORE COOLING SYSTEM (ECCS) MODEL CHANGES PURSUANT TO THE REQUIREMENTS OF 10 CFR 50.46 2005 ANNUAL REPORTING OF 10 CFR 50.46 MARGIN UTILIZATION VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNITS 1 AND 2
Serial Number 06-521 Docket No. 50-3381339 10 CFR 50.46 Annual Report Page 1 of 10 10 CFR 50.46 MARGIN UTILIZATION - WESTINGHOUSE SMALL BREAK LOCA Plant Name:
North Anna Power Station, Unit 1 Utility Name:
Virginia Electric and Power Company Analvsis Information EM:
NOTRUMP Limiting Break Size: 3 Inches Analysis Date:
1995 Vendor:
Westing house FQ:
2.32 FAH :
1.65 Fuel:
NAl F SGTP (%):
7 Notes:
None Clad T e m ~
(OF)
Notes LICENSING BASIS Analysis of Record PCT 1704 PCT ASSESSMENTS (Delta PCT)
A.
Priior ECCS Model Assessments
- 1.
NOTRUMP Specific Enthalpy Error 20
- 2.
SALIBRARY Double Precision Error
-1 5
- 3.
Fuel Rod Initialization Error 10
- 4.
Loop Seal Elevation Error
-44
- 5.
NOTRUMP-Mixture Level Tracking Errors 13 1
(1)
- 6.
Removal of Part Length CRDMs
- 7.
(11 NOTRUMP-Bubble RiseIDrift Flux Model Inconsistencies 35 (1)
B.
Plirnned Plant Modification Evaluations
- 1.
None C.
2005 ECCS Model Assessments
- 1.
None D.
Otlher
- 1.
None LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
1724 Notes:
(1)
The accumulation of changes for these items (sum of absolute magnitudes) since the last 30-day report or reanalysis is less than or equal to 50°F and is not significant, as defined in 10 CFR 50.46(a)(3)(i).
Serial Number 06-521 Docket No. 50-3381339 10 CFR 50.46 Annual Report Page 2 of 1 0 10 CFR 50.46 MARGIN UTILIZATION - WESTINGHOUSE LARGE BREAK LOCA Plant Name:
North Anna Power Station, Unit 1 Utility Name:
Virginia Electric and Power Company Analvsis Information EM:
BASH Limiting Break Size: Cd=0.4 Analysis Date:
2004 Vendor:
Westing house FQ:
2.19 FAH :
1.55 Fuel:
NAl F SGTP (Oh):
7 Notes:
None Clad T e m ~
(OF)
Notes LlCENSllNG BASIS An~alysis of Record PCT PCT ASSESSMENTS (Delta PCT)
A.
Prior ECCS Model Assessments
- 1.
LOCBART Fluid Property Logic Issue B.
Plisnned Plant Modification Evaluations
- 1.
None C.
2005 ECCS Model Assessments
- 1.
None D.
Other
- 1.
None LICENSII\\IG BASIS PCT + PCT ASSESSMENTS PCT =
2086 Notes:
{I)
The accumulation of changes for these items (sum of absolute magnitudes) since the last 30-day report or reanalysis is less than or equal to 50°F and is not significant, as defined in 10 CFR 50.46(a)(3)(i).
J UTILIZATION -
Serial Number 06-521 Docket No. 50-3381339 10 CFR 50.46 Annual Report Page 3 of 10 rlA SMALL BREAK LOCA Plant Name:
North Anna Power Station, Unit 1 Utility Name:
Virginia Electric and Power Company Analvsis Information EM:
AREVA SB EM Limiting Break Size: 5.2 Inches (SI Line)
Analysis Date:
2004 Vendor:
AREVA FQ:
2.32 FAH:
1.65 Fuel:
Advanced Mark-BW SGTP (%):
7 Notes:
None Clad T e m ~
(OF)
Notes LICENSING BASIS Analysis of Record PCT 1404 PCT ASSESSMENTS (Delta PCT)
A.
Priior ECCS Model Assessments
- 1.
None 0
B.
Planned Plant Modification Evaluations
- 1.
Revised Test Flow Curve for HHSl
-24 (1)
C.
20105 ECCS Model Assessments
- 1.
None 0
(1)
D.
Other
- 1.
None 0
LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
1380 Notes:
{I)
The accumulation of changes for these items (sum of absolute magnitudes) since the last 30-day report or reanalysis is less than or equal to 50°F and is not significant, as defined in 10 CFR 50.46(a)(3)(i).
Serial Number 06-521 Docket No. 50-3381339 10 CFR 50.46 Annual Report Page 4 of 1 0 10 CFR 50.46 MARGIN UTILIZATION - AREVA LARGE BREAK LOCA Plant Narme:
North Anna Power Station, Unit 1 Utility Nrrme:
Virginia Electric and Power Company Analvsis Information EM:
AREVA RLBLOCA EM Limiting Break Size: DEGB Analysis Date:
2004 Vendor:
AREVA FQ:
2.32 FAH :
1.65 Fuel:
Mixed SGTP (%):
12 NAI FIAdvanced Mark-BW Notes:
None LICENSING BASIS Analysis of Record PCT PCT ASSESSMENTS (Delta PCT)
A.
Priior ECCS Model Assessments 1.
Forslund-Rohsenow Correlation Modeling
- 2.
RWST Temperature Assumption
- 3.
LBLOCNSeismic SG Tube Collapse B.
Planned Plant Modification Evaluations
- 1.
Advanced Mark-BW Top Nozzle Modification C.
20105 ECCS Model Assessments
- 1.
RLBLOCA Choked Flow Disposition Clad T e m ~
(OF)
Notes 1853
- 2.
RLBLOCA Changes in uncertainty Parameters 10 D.
Otlher
- 1.
None LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
1974 Notes:
(1)
A generic steam generator LOCNseismic load evaluation was performed by Wctstinghouse to quantify the potential steam generator tube collapse, which ma.y occur at the time of the LOCA due to combined LOCA and seismic loads.
Based on this analysis, a total steam generator tube reduction equivalent to 5%
tube plugging was allocated as a permanent assessment for those plants that do not have a detailed analysis. The 5% steam generator tube plugging reduction will be used to account for the effects of a combined LOCA/seismic event at North Anna Unit 1 with the AREVA evaluation model.
Serial Number 06-521 Docket No. 50-3381339 10 CFR 50.46 Annual Report Page 5 of 10 (2)
All current and prior PCT assessments have been previously reported to the NRC to meet the 30-Day reporting requirements of 1 0 CFR50.46 (a)(3)(ii). Therefore, the current accumulation of PCT assessments is 0°F.
Serial Number 06-521 Docket No. 50-3381339 10 CFR 50.46 Annual Report Page 6 of 10 10 CFR 50.46 MARGIN UTILIZATION - WESTINGHOUSE SMALL BREAK LOCA Plant Na~me:
North Anna Power Station, Unit 2 Utility Name:
Virginia Electric and Power Company Analvsis Information EM:
NOTRUMP Limiting Break Size: 3 Inches Analysis Date:
1995 Vendor:
Westinghouse FQ:
2.32 FAH:
1.65 Fuel:
NAIF SGTP (%):
7 Notes:
None Clad T e m ~
( O F )
Notes LICENSING BASIS Analysis of Record PCT 1 704 PCT ASSESSMENTS (Delta PCT)
A.
Priior ECCS Model Assessments
- 1.
NOTRUMP Specific Enthalpy Error 20
- 2.
SALIBRARY Double Precision Error
-1 5
- 3.
Fuel Rod Initialization Error 10
- 4.
Loop Seal Elevation Error
-44
- 5.
Removal of Part Length CRDMs 1
13
{I)
- 6.
NOTRUMP-Mixture Level Tracking Errors (1)
- 7.
NOTRUMP-Bubble RiselDrift Flux Model Inconsistencies 35 (1)
B.
Planned Plant Modification Evaluations
- 1.
None C.
2005 ECCS Model Assessments
- 1.
None D.
Other
- 1.
None LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
1724 Notes:
{I)
The accumulation of changes for these items (sum of absolute magnitudes) since the last 30-day report or reanalysis is less than or equal to 50°F and is not significant, as defined in 10 CFR 50m46(a)(3)(i).
Serial Number 06-521 Docket No. 50-3381339 10 CFR 50.46 Annual Report Page 7 of 1 0 10 CFR 50.46 MARGIN UTILIZATION - WESTINGHOUSE LARGE BREAK LOCA Plant Na~me:
North Anna Power Station, Unit 2 Utility Name:
Virginia Electric and Power Company Analvsis Information EM:
BASH Limiting Break Size: Cd=0.4 Analysis Date:
2004 Vendor:
Westinghouse FQ:
2.1 9 FAH :
1.55 Fuel:
NAIF SGTP (%):
7 Notes:
None Clad T
~
D
( O F )
Notes LICENSING BASIS Analysis of Record PCT 2086 PCT ASSESSMENTS (Delta PCT)
A.
Prior ECCS Model Assessments
- 1.
LOCBART Fluid Property Logic Issue 0
(1)
B.
Planned Plant Modification Evaluations
- 1.
None 0
C.
2005 ECCS Model Assessments
- 1.
None 0
(1)
D.
Otlher
- 1.
None 0
LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
2086 Notes:
{I)
The accumulation of changes for these items (sum of absolute magnitudes) since the last 30-day report or reanalysis is less than or equal to 50°F and is not significant, as defined in 10 CFR 50.46(a)(3)(i).
Serial Number 06-521 Docket No. 50-3381339 10 CFR 50.46 Annual Report Page 8 of 10 10 CFR 50.46 MARGIN UTILIZATION - AREVA SMALL BREAK LOCA Plant Name:
North Anna Power Station, Unit 2 Utility Name:
Virginia Electric and Power Company Analvsis Information EM:
AREVA SB EM Limiting Break Size: 3 Inches Analysis Date:
2004 Vendor:
AREVA FQ:
2.32 FAH:
1.65 Fuel:
Advanced Mark-BW SGTP (YO):
7 Notes:
None Clad T e m ~
(OF)
Notes LICENSING BASIS Analysis of Record PCT PCT ASSESSMENTS (Delta PCT)
A.
Prior ECCS Model Assessments
- 1.
None B.
Planned Plant Modification Evaluations
- 1.
None C.
2005 ECCS Model Assessments
- 1.
None D.
Otlher
- 1.
None LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
1370 Notes:
{I)
The accumulation of changes for these items (sum of absolute magnitudes) since the last 30-day report or reanalysis is less than or equal to 50°F and is not significant, as defined in 10 CFR 50.46(a)(3)(i).
Serial Number 06-521 Docket No. 50-3381339 10 CFR 50.46 Annual Report Page 9 of 10 10 CFR 50.46 MARGIN UTILIZATION - AREVA LARGE BREAK LOCA Plant Name:
North Anna Power Station, Unit 2 Utility Name:
Virginia Electric and Power Company Analvsis Information EM:
AREVA RLBLOCA EM Limiting Break Size: DEGB Analysis Date:
2004 Vendor:
AREVA FQ:
2.32 FAH :
1.65 Fuel:
Mixed:
SGTP (Oh):
12 NAI FIAdvanced Mark-BW Notes:
None Clad Temr, ( O F )
Notes LICENSING BASIS Analysis of Record PCT 1789 PCT ASSESSMENTS (Delta PCT)
A.
Prior ECCS Model Assessments 1.
Forslund-Rohsenow Correlation Modeling
- 2.
RWST Temperature Assumption
- 3.
LBLOCNSeismic SG Tube Collapse B.
Planned Plant Modification Evaluations
- 1.
Advanced Mark-BW Top Nozzle Modification C.
2005 ECCS Model Assessments
- 1.
RLBLOCA Choked Flow Disposition
- 2.
RLBLOCA Changes in Uncertainty Parameters D.
Otlher
- 1.
None LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
1958 Notes:
(1)
A generic steam generator LOCNseismic load evaluation was performed by Wctstinghouse to quantify the potential steam generator tube collapse, which may occur at the time of the LOCA due to combined LOCA and seismic loads.
Based on this analysis, a total steam generator tube reduction equivalent to 5%
tube plugging was allocated as a permanent assessment for those plants that do not have a detailed analysis. The 5% steam generator tube plugging reduction will be used to account for the effects of a combined LOCNseismic event at North Anna Unit 2 with the AREVA evaluation model.
Serial Number 06-521 Docket No. 50-3381339 10 CFR 50.46 Annual Report Page 10 of 10 (2) All current and prior PCT assessments have been previously reported to the NRC to meet the 30-Day reporting requirements of 10 CFR 50.46(a)(3)(ii). Therefore, the current accumulation of PCT assessments is 0°F.
Serial Number 06-521 Docket Nos. 50-2801281 ATTACHMENT 5 2005 ANNUAL REPORT OF EMERGENCY CORE COOLING SYSTEM (ECCS) MODEL CHANGES PURSUANT TO THE REQUIREMENTS OF 10 CFR 50.46 2!005 ANNUAL REPORTING OF 10 CFR 50.46 MARGIN UTILIZATION VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION UNITS 1 AND 2
Serial Number 06-521 Docket Nos. 50-2801281 10 CFR 50.46 Annual Report Page 1 of 6 10 CFR 50.46 MARGIN UTILIZATION - WESTINGHOUSE SMALL BREAK LOCA Plant Name:
Surry Power Station, Unit 1 Utility Name:
Virginia Electric and Power Company Analvsis Information EM:
NOTRUMP Limiting Break Size: 3 Inches Analysis Date:
1996 Vendor:
Westing house FQ:
2.5 FAH :
1.7 Fuel:
SI F SGTP (YO):
15 Notes:
None Clad T e m ~
(OF)
Notes LICENSING BASIS An~alysis of Record PCT 171 7 PCT ASSESSMENTS (Delta PCT)
A.
Prior ECCS Model Assessments
- 1.
NOTRUMP - Mixture Level Tracking Errors 13
- 2.
Removal of Part Length CRDMs
-1 5
- 3.
NOTRUMP-Bubble RiseIDrift Flux Model Inconsistencies 35 B.
Planned Plant Modification Evaluations
- 1.
Westinghouse IFBA Fuel Product Implementation 10 (11 C.
2005 ECCS Model Assessments
- 1.
None D.
Other
- 1.
None LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
1760 Notes:
{I)
The accumulation of changes for these items (sum of absolute magnitudes) sir~ce the last 30-day report or reanalysis is less than or equal to 50°F and is not significant, as defined in 10 CFR 50.46(a)(3)(i).
Serial Number 06-521 Docket Nos. 50-2801281 10 CFR 50.46 Annual Report Page 2 of 6 10 CFR 50.46 MARGIN UTILIZATION - WESTINGHOUSE LARGE BREAK LOCA Plant Name:
Surry Power Station, Unit 1 Utility Name:
Virginia Electric and Power Company Analvsis Information EM:
BASH Limiting Break Size: Cd=0.4 Analysis Date:
2001 Vendor:
Westing house FQ:
2.32 FAH :
1.62 Fuel:
SI F SGTP (%):
15 Notes:
None Clad T e m ~
(OF)
Notes LICENSING BASIS Analysis of Record PCT 21 17 PCT ASSESSMENTS (Delta PCT)
A.
Prior ECCS Model Assessments
- 1.
LBLOCA/Seismic SG Tube Collapse
- 2.
- 3.
LOCBART Fluid Property Logic Issue B.
Planned Plant Modification Evaluations 1.
Westinghouse IFBA Fuel Product Implementation 41 C.
2005 ECCS Model Assessments
- 1.
LOCBART ZIRLOT~ Cladding Specific Heat Model Error
- 2.
PAD 4.0 Initial Pellet Temperatures
- 3.
Removal of Part-Length CRDMs
- 4.
Pressurizer Surge Line Piping Schedule Reconciliation
- 5.
LOCBART Fluid Property Logic Issue-Augmented
- 6.
Revised Containment Heat Sink Input
- 7.
Revised Containment Spray Flowrate
- 8.
Revised Containment Free Volume D.
2006 ECCS Model Assessments
- 1.
LOCBART Fluid Property Logic Issue-Augmented (2)
-10 E.
Other
- 1.
None LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
2194
Serial Number 06-521 Docket Nos. 50-2801281 10 CFR 50.46 Annual Report Page 3 of 6 Notes:
(1)
A generic steam generator LOCAIseismic load evaluation was performed by Westinghouse to quantify the potential steam generator tube collapse, which may occur at the time of the LOCA due to combined LOCA and seismic loads.
Based on this analysis, a total steam generator tube reduction equivalent to 5%
tube plugging was allocated as a permanent assessment for those plants that do not have a detailed analysis. The 5% steam generator tube plugging reduction will be used to account for the effects of a combined LOCAIseismic event at Surry.
(2)
All current and prior PCT assessments have been previously reported to the NRC to meet the 30-Day reporting requirements of 10 CFR 50.46(a)(3)(ii). Therefore, the current accumulation of PCT assessments is 0°F.
Serial Number 06-521 Docket Nos. 50-2801281 10 CFR 50.46 Annual Report Page 4 of 6 10 CFR 50.46 MARGIN UTILIZATION - WESTINGHOUSE SMALL BREAK LOCA Plant Name:
Surry Power Station, Unit 2 Utility Name:
Virginia Electric and Power Company Analvsis Information EM:
NOTRUMP Limiting Break Size: 3 Inches Analysis Date:
1996 Vendor:
Westing house FQ:
2.5 FAH :
1.7 Fuel:
SI F SGTP (%):
15 Notes:
None Clad Temr, (OF)
Notes LICENSING BASIS Analysis of Record PCT 171 7 PCT ASSESSMENTS (Delta PCT)
A.
Prior ECCS Model Assessments
- 1.
NOTRUMP - Mixture Level Tracking Errors 13
- 2.
Removal of Part Length CRDMs
-1 5
- 3.
NOTRUMP-Bubble RiseIDrift Flux Model Inconsistencies 35 B.
Planned Plant Modification Evaluations
- 1.
Westinghouse IFBA Fuel Product Implementation 10 (1)
C.
2005 ECCS Model Assessments
- 1.
None D.
Other
- 1.
None LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
1760 Notes:
(1)
The accumulation of changes for these items (sum of absolute magnitudes) since the last 30-day report or reanalysis is less than or equal to 50°F and is not siglnificant, as defined in 10 CFR 50.46(a)(3)(i).
Serial Number 06-521 Docket Nos. 50-280/281 10 CFR 50.46 Annual Report Page 5 of 6 I0 CFR 50.46 MARGIN UTILIZATION - WESTINGHOUSE LARGE BREAK LOCA Plant Name:
Surry Power Station, Unit 2 Utility Name:
Virginia Electric and Power Company Analvsis Information EM:
BASH Limiting Break Size: Cd=0.4 Analysis Date:
2001 Vendor:
Westing house FQ:
2.32 FAH:
1.62 Fuel:
SIF SGTP (%):
15 Notes:
None Clad T e m ~
( O F )
Notes LICENSING BASIS An~alysis of Record PCT 21 17 PCT ASSESSMENTS (Delta PCT)
A.
Prior ECCS Model Assessments
- 1.
LBLOCAlSeismic SG Tube Collapse
- 2.
- 3.
LOCBART Fluid Property Logic Issue B.
Pl~nned Plant Modification Evaluations
- 1.
Westing house IFBA Fuel Product Implementation 41 C.
2005 ECCS Model Assessments
- 1.
LOCBART ZIRLOTM Cladding Specific Heat Model Error
- 2.
PAD 4.0 Initial Pellet Temperatures
- 3.
Removal of Part-Length CRDMs
- 4.
Pressurizer Surge Line Piping Schedule Reconciliation
- 5.
LOCBART Fluid Property Logic Issue-Augmented
- 6.
Revised Containment Heat Sink Input
- 7.
Revised Containment Spray Flowrate
- 8.
Revised Containment Free Volume D.
2006 ECCS Model Assessments (2)
- 1.
LOCBART Fluid Property Logic Issue-Augmented
-1 0 E.
Other
- 1.
None LICENSING BASIS PCT + PCT ASSESSMENTS PCT =
2194
Serial Number 06-521 Docket Nos. 50-2801281 10 CFR 50.46 Annual Report Page 6 of 6 Notes:
A generic steam generator LOCNseismic load evaluation was performed by Westinghouse to quantify the potential steam generator tube collapse, which may occur at the time of the LOCA due to combined LOCA and seismic loads.
Based on this analysis, a total steam generator tube reduction equivalent to 5%
tube plugging was allocated as a permanent assessment for those plants that do not have a detailed analysis. The 5% steam generator tube plugging reduction will1 be used to account for the effects of a combined LOCNseismic event at Surry.
All current and prior PCT assessments have been previously reported to the NRC to meet the 30-Day reporting requirements of 10 CFR 50.46(a)(3)(ii). Therefore, the current accumulation of PCT assessments is 0°F.