ML14177A725
| ML14177A725 | |
| Person / Time | |
|---|---|
| Site: | Watts Bar  |
| Issue date: | 06/25/2014 |
| From: | Arent G Tennessee Valley Authority |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| TAC ME3334 | |
| Download: ML14177A725 (100) | |
Text
Tennessee Valley Authority, Post Office Box 2000, Spring City, Tennessee 37381-2000 June 25, 2014 10 cFR 50.4 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Watts Bar Nuclear Plant, Unit 2 NRC Docket No. 50-391
Subject:
WATTS BAR NUCLEAR PLANT (wBN) UNIT 2 - PROBABILISTIC RtsK ASSESSMENT (PRA)
SUMMARY
REPORT - INFORMATION PREVTOUSLY COMMITTED TO PROVIDE (TAC NO. ME3334)
References:
- 1. TVA letter dated February 9,2010, Watts Bar Nuclear Plant (WBN)
Unit 2 - Probabilistic Risk Assessment lndividual Plant Examination Summary Report"
- 2. TVA letter dated June 8, 2010, "Watts Bar Nuclear Plant WBN) Unit 2
- Request forAdditional lnformation Regarding lndividual Plant Examination (TAC No. ME3334)"
The purpose of this letter is to provide information previously committed to in References 1 and 2 above. ln Reference 1, TVA committed to confirming that the Unit 2 PRA model matches the as-built, as-operated plant. Enclosure 1 provides TVA Calculation MDN-000-999-2008-0151, R1, 'WBN Probabilistic Risk Assessment -
Summary Document," which satisfies this commitment. lt should be noted that the calculation provided in Enclosure 1 contains icon links to other documents. These other documents are available, if needed, for NRC review at TVA's corporate offices.
Regarding the second commitment, in Reference2, TVA committed to provide information regarding how the model and the peer review process addresses the items in the Regulatory Guide 1.200, Revision 2 tables related to internal events including internal flooding for which the NRC endorsed position included "Qualifications," that required response. Enclosure 2 provides the information required to satisfy this commitment.
U.S. Nuclear Regulatory Commission Page2 June 25,2014 There are no new commitments contained in this letter. lf you have any questions, please contact me at (423) 365-2004.
I declare under penalty of perjury that the foregoing is true and correct. Executed on the 25h day of June, 2014.
Respectfully, Mt 1.
2.
Director, Licensing Watts Bar
Enclosures:
WBN Probabilistic Risk Assessment - Summary Document lnformation Related to how the Model and the Peer Review Process Addressed the Items in the Regulatory Guide 1.200 Revision 2 Tables cc (Enclosures):
U. S. Nuclear Regulatory Commission Region Il Marquis One Tower 245 Peachtree Center Ave., NE Suite 1204 Atlanta, Georgia 30303-1257 NRC Resident lnspector Unit 1 Watts Bar Nuclear Plant 1260 Nuclear Plant Road Spring City, Tennessee 37381 NRC Resident lnspector Untt2 Watts Bar Nuclear Plant 1260 Nuclear Plant Road Spring City, Tennessee 37381
ENCLOSURE 1 Tennessee Valley Authority Watts Bar Nuclear Plant, Unat2 Docket No. 50-391 WBN Probabilistic Risk Assessment - Summary Document E1-1
NPG CALCULATION COVERSHEET CTS UPDATE t14 WBN Probabilistic Risk Assessment - Summary Document MDN-000-9992008-0151 crs UPDATE ot-tly E (Verifier and Approval Signatures Not Required)
NO CTS CHANGES g (For calc revislon, crs has been reviewed and no crs changes required)
IJNII (check one)
OEI, 1E,2EI,Str
$YSTEMS 999 UNIDS rvA APPLTCABLE pgFlgN pocu MENI(S) tl/A SAFETY RELATED?
(lf yes, QR = yes)
Yes El No El Yes EI tto El CALCULATTON NUJ4EIER REOUESTOR.
Name: N/A Phone:
PREPARER (PRINT NAME AND SlGN)
GHECKER (PRlNT NAME AND SIGN)
Bradley W. Dolan,f,
VERIFIER (PRINT NAME AND SIGN)
APPROVAL (PRlNT NAME AhrD SrcN)
STATEMENT OF PROBLEITT/ABSTRACT Abstract:
This calculation documents a sumrnary of the wBN pRA.
No E FrcHE NUMEERG)
Page 1 af2 10-31-201 1l
NPG CALCULATION COVERSHEET / CTS UPDATE CROSS-REFERE NCES (A-add, D-delete)
Page 2 CALC ID ORG PLANT BRANCH NUMBER REV NUC WBN MEB M DN-000-999-2008-0 1 5 1 001 BUTLDTNGIROOMIELEVATlONICOORp/MIM FIRM CATEGORIES KEYWORDS (A-add, D-delete)
ACTION (A/D)
KEYWORD 1@
KEY}VORD ACTION (A/D)
XREF CODE XREF PLANT XREF TYPE XREF NUMBER XREF REV CTS ONLY UPDATES:
Following are required only when making keyword/cross reference CTS updates and page 1 of form NEDP-2-1 is not included:
PREPARER (PRINT NAME AND SIGN)
DATE CHECKER (PRINT NAME AND SIGN)
DATE PREPARER PHONE NO.
EDMS ACCESSION NO.
TVA 40s32 Page 2 of 2 NEDP-2-1 t10-31 -2011h
NPG CALCULATION RECORD OF REVISION calculation ldentifier: MDN-000-ggg-2009-01 s1 WBN Probabilistic Risk Assessment - Summ ary Document DESCRIPTION OF REVISION lnitial lssue The safety Analysis Report (sAR) has been revierared by /s/ carla A. Bonelli (11116/10) and this revision of the carcuration does not affect tne sAn]-
The Tech Specs have been reviewed and have been determined to not be affected.
Total Number of Pages = 383 Summary Notebook updated to reflect the update model information.
- ilE,3;f fl#lilf'lT"ffillf ffiJ,T
- ?,::ff^:"ff *ov@*,/a/t.na The Tech Specs have been reviewed and have been determined to not be affected.
Total Number of Pages = 29S TVA 40709 [10-2008]
Page: 3 NEDP-2 -2110-20-2008I
Page: 4 NPG CALCULATION TABLE OF CONTENTS Calculation ldentifier: MDN-000-999-2008-01 51 Revision: 001 TABLE OF CONTENTS SECTION TITLE PAGE NPG Calculation Coversheet / CTS Update
..............1 NPG Galculation Record Of Revision..............
........3 NPG Calculation Table Of Contents............
..............4 NPG Computer Input File Storage Information Sheet
.............9 1.0 Purpose
....................10 2.0 References and Acronyms
.......10 2.2 Acronyms..
....................13 3.0 Design lnput
.............15 4.0 Assumptions..........
...................15 5.0 Special Requirements/Limiting Conditions.......
.......15 6.0 Computations and Analyses.
....................15 6.'l Model Deve1opment..................
.......15 6.1.1 lnitiating Events.........
................. 15 6.1.2 Accident Sequences Analysis......
..................17 6.1.3 Success Criteria
.....18 6.1.4 Systems Analysis......
................. 19 6.1.5 Data Ana1ysis.................
............20 6.1.6 Human Reliability Analysis......
.......................22 6.1.7 lntemal Flooding
........................22 6.1.8 Large Early Release FrequencyAnalysis......
....................23 6.1.9 Quantification.................
............24 6.1.10 Maintenance & Update/Configuration Control (MU)...........
...................24 6.1.11 Softryare
.................25 6.1.12 Resolution of F&Os from Peer Review of the RISKMAN R4 Model..........................25 6.1.13 Resolution of F&Os from Peer Review of the CAFTA R0 model....
.......25 6.'1.14 Major Changes from Riskman R4 model to the CAFTA R0 mode1............................ 26 6.2 Results.......
....................26 6.2.'l Core Damage Frequency
...........26 6.2.2 Large Early Release Frequency
....................29 7.0 Supporting Graphics..............
...................31
Page: 5 NPG CALCULATION TABLE OF CONTENTS Calculation ldentifier: MDN-000-999-2008-0151 Revislon: 001 TABLE OF CONTENTS SECTION TITLE PAGE 7.2 8.0 Tables Table I - lnitiating Events
....................31 Table 2 - Summary of WBN lnitiating Event Evidence....
..........39 Table 3 - lnitiating Event Prior and Posterior Distributions.................
........40 Table 4 Comparison of lnitiating Event Frequencies
................51 Table 5 - Plant Damage States.........
.......................53 Table 6 - lnitiating Event Linkage to Accident Sequence Event Trees
......54 Table 7 -- Success Criteria for LLOCA
................... 56 Table 8 - Success Criteria for MLOCA
...................57 Table 9 -- Success Criteria for SLOCA.
.................. 59 Table 10 -- Success Criteria for SLOCAV
............... 63 Table 11 -- Success Criteria for SSBI
..................... 64 Table 12 -- Success Criteria for SSBO....
................67 Table 13 -- Success Criteria for GTRAN.
................71 Table 14 -- Success Criteria for SGTR....
................72 Table 15 -- Success Criteria for ATWS
................... 76 Table 16 -- Success Criteria for ISLOGA
................78 Table 17 - Success Criteria Gomparison: LLOCA
...................80 Table 18 - Success Criteria Comparison: MLOCA
.................. 81 Table 19 - Success Criteria Comparison: SLOCA....
...............83 Table 20 - Success Criteria Comparison: SLOGAV..
...............85 Table 21 - Success Criteria Gomparison: Transient
...............87 Table 22-Success Griteria Comparison:
SGTR!
t t. t t t r.rr... t...r.......
- r. r.............t t t.................!...
89 Table 23 - MAAP Runs...........
..............91 Table24 - Comparison of RCP Seal Leaks.
...........99 Table 25.- Probabilities of RCP Seal Leaks.
..........99 Table 26.. Time to HPR........
.............. 100 Table27.. Time to LPR........
..............100 Table 28 -- HRA Support Timings
.....101 Table 29 -- WBN PRA System Notebooks
............ 105 Table 30 - Component Failure Rates..........
.......... 106 Table 31 - Component Failure Rate Comparison..........
.........111 Table 32.- Unavailability Results
......113 Table 33.. Unavailability Comparison...........
.......121 Table 34.. Common Cause Groups and MGL Variables
........122 7.1
Page: 6 NPG CALCULATION TABLE OF CONTENTS Calculation ldentifier: MDN-000-999-2008-01 51 Revision: 001 TABLE OF CONTENTS SECTION TITLE PAGE Table 35.. Comparison of MGL Variables....
........123 Table 36 - Summary of Pre-lnitiatorActions and Probabilities..........
...... 130 Table 37 -- Summary of Post-lnitiator Actions and Probabilities..........
.... 131 Table 38 --Summaryof Flooding RecoveryActions and Probabilities..........
..............135 Table 39.. Comparison of HEPs
....... 136 Table 40.. Summary of Flood Sources Analyzed in lF-PRA...
.................. 138 Table 41.. Sample Propagation Path Calculation...........
........141 Table 42 - Qualitative Screening Assessment of Flooding Sources, Auxiliary Buitding...............142 Table 43 - Qualitative Screening Assessment of Flooding Sources, Control Buitdlng.................142 Table 44 - Qualitative Screening Assessment of Flooding Sources, Diesel Generator Building. 142 Table 45 - Qualitative Screening Assessment of Flooding Sources, lntake Pumping Station.....142 Table 46 - Qualitative Screening Assessment of Flooding Sources, Turbine 8ui1din9.................142 IiI!:liilIi[=illmirmfu,#,,1...::::::::::::::::::::........................:::::.::':::lli Table 51 - Listing and Description of WBN PRA Mode! Fi1es............
.........'146 Table 52 - Listing and Description of Software Used for WBN PRA
.........147 Table 53 - (Not Used)
.....148 Table 54 - Summary of CDF and LERF..
............... 149 Table 55 - CDF Results By Accident Sequence for Unit 1..................
....... 150 Table 56 - Breakdown of CDF Gutsets in Each Frequency Range, Unit 2.........
............ 151 Table 57 - Top 100 Cutsets for Unit 1 CDF
..........152 Table 58 - Top 100 Cutsets for Unit 2 CDF
.......... 153 Table 59 - CDF By lnitiator for Unit 1..................
..................... 154 Table 60.. Unit I CDF Gomparison
......................156 Table 61.. CDF By lnitiator for Unit 2..................
..................... 157 Table 62.. Unit I System lmportance for CDF, F-V > 0.5%.
... 159 Table 63 - Unit 1 System lmportance for CDF, RAW > 2.................
.......... 160 Table 64.- Unit 2 System lmportance for CDF, F-V > 0.5%.
....................... 161 Table 65 - Unit 2 System lmportance for CDF, RAW > 2.................
.......... 162 Table 66 - Unit 1 Component lmportance for CDF, F-V > 0.5%........
......... 163 Table 67 - Unit 1 Component lmportance for CDF, RAW > 2..............
......164 Table 68 - Unit 2 Component lmportance for CDF, F-V > 0.5%........
.........171 Table 69 - Unit 2 Component lmportance for CDF, RAW > 2..............
......172 Table 70 - Unit 1 HRA CDF lmportance F-V >0.5%.........
........179 Table 71 - Unit 1 HRA CDF lmportance RAW >2...............
.....180 TableT2 - Unit 2 HRA CDF lmportance F-V >0.5%.........
........181 Table 73 - Unit 2 HRA CDF lmportance RAW > 2..............
.....182 Table 74.. Unit 1 Basic Event GDF lmportance F-V >0.5%
....183 Table 75 - Unit 1 Basic Event CDF lmportance RAW > 2..............
.............185 Table 76 - Unit 2 Basic Event CDF lmportance F-V >0.5o/o
....199 Table 77 - Unit 2 Basic Event CDF lmportance RAW > 2...............
............202 Table 78 - Unit 1 Test and Maintenance CDF lmportance F-V > 0.5%.
.....217 Table 79 - Unit 1 Test and Maintenance GDF lmportance RAW > 2.................
............218 Table 80.. Unit 2 Test and Maintenance CDF lmpoftance F-V >0.5%..
.....219 Tabfe 81 - Unit 2 Test and Maintenance CDF lmportance RAW > 2.................
............220 Table 82 - LERF By Accident Sequence for Unit 1..................
...................221
Page: 7 NPG CALCULATION TABLE OF CONTENTS Calculation ldentifier: MDN-000-999-2008-01 51 Revision: 001 TABLE OF CONTENTS SECTION TITLE PAGE Table 83 - Breakdown of LERF Gutsets in Each Frequency Range, Unit 2.........
..........222 Table 84 - Top 100 Cutsets for Unlt 1 LERF
........223 Table 85 - Top 100 Cutsets for Unit 2 LERF
........223 Table 86 - (Not Used)..........
...............224 Table 87 - (Not Used)..........
...............224 Table 88: (Not Used).
.....225 Table 89: (Not Used)
.......225 Table 90: (Not Used).
.....225 Table 9l -- LERF By lnitiatorfor Unit 1
.................226 Table 92 - Unit 1 LERF Comparison
....................227 Table 93 - LERF By lnitiatorfor Unit 2.......
..........228 Table 94 - Unit 1 System lmportance for LERF, F-V > 0.5%
......................229 Table 95 - Unit 1 System lmportance for LERF, RAW > 2.................
........229 Table 96 - Unit 2 System lmportance for LERF, F-V > 0.5%
......................230 Table 97 - Unit 2 System lmpoftance for LERF, RAW > 2.................
........230 Table 98 - Unit 1 Gomponent lmportance for LERF, F-V > 0.5%.
..............231 Table 99 - Unit 1 Component lmportance for LERF, RAW > 2.................
.....................232 Table 100 - Unit 2 Component lmportance for LERF, F-V > 0.5%.
............234 Table 101 - Unit 2 Component lmportance for LERF, RAW > 2.................
...................235 Table 102 - Unit 1 HRA LERF lmportance F-V >0.5%.........
....237 Table 103 - Unit 1 HRA LERF lmportance RAW > 2..............
..................... 238 Table 104 - Unit 2 HRA LERF lmportance F-V >0.5%.........
....239 Table 105 - Unlt 2 HRA LERF lmportance RAW > 2.-----...
.....................240 Table 106 - Unit 1 Basic Event LERF lmportance F-V >0.5o/o
....................241 Tabfe 107 - Unit 1 Basic Event LERF lmportance RAW > 2..............
.........243 Table 108 - Unit 2 Basic Event LERF lmportance F-V >0.5%
....................24 Table 109 - Unit 2 Basic Event LERF lmportance RAW > 2..............
.........250 Table 110.. Unit 1 Test and Maintenance LERF lmpoftance F-V >0.5%..
.....................255 Table 111 - Unit I Test and Maintenance LERF Importance RAW > 2.................
........256 Table 112 - Unit 2 Test and Maintenance LERF lmportance F-V >0.5%..
.....................257 Table 113 - Unit 2 Test and Maintenance LERF lmportance RAW > 2.................
........258 lliffilm*..........................'.-..............:.....:..............................:.....:........:.lfi Figure 10 - ISLOCA Event Tree...........
.................. 269 Figure 11 - Maior Phases and Tasks of IF-PRA
......................270 Figure 12 - Sample Propagation Path Diagram................
.,....271 Figure 13 - Unit 1 Flooding CDF............
...............272 Figure 14 - Unit 1 Flooding LERF..........
...............273
NPG GALCULATION TABLE OF CONTENTS Calculation ldentifier: MDN-000-999-2008-01 51 Revision: 001 TABLE OF CONTENTS SECTION TITLE PAGE Figure 15.. Unit 2 Flooding CDF............
Figure 16.. Unit 2 Flooding LERF..........
Figure 17 - Containment Event Tree............
Figure 18 - lndustry Comparison of CDF........
Figure 19 - Unit 1 CDF Uncertainty P1ot............
Figure 20 - Unit 2CDF Uncertainty Plot............
Figure 21 - Unit 1 GDF lnitiator Distribution Figure 22 -Unil2 CDF lnitiator Distribution Figure 23 - LERF Comparison wlth Westinghouse 4-loop Plants Figure 24 - LERF Comparison with Westinghouse lce Condenser Containments Figure 25 - Unit 1 LERF Uncertainty Plot............
Figure 26 - Unit 2 LERF Uncertainty P1ot............
Figure 27 -Unil l LERF Phenomena Distribution Figure 28 - Unit 2 LERF Phenomena Distribution Figure 29 - Unit 1 LERF PDS Distribution..........
Figure 30 - Unit 2 LERF PDS Distribution..........
Figure 31 - Unit 1 LERF lnitiator Contributions.................
Figure 32 - Unit 2 LERF lnitiator Contributions.................
274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 Page: I NEDP-2-3 [10-20-2008]
TVA 40710 [10-2008]
NPG COMPUTER INPUT FILE STORAGE INFORMATION SHEET Document MDN-000-999-2008-0151 I Rev. 001 I Plant: WBN
Subject:
Probabilistic Risk Assessment - Summary Document n
Electronic storage of the input files for this calculation is not required. Comments:
x lnput files for this calculation have been stored electronically and sufficient identiffing information is provided below for each input file. (Any retrieved file requires re-verification of its contents before use.)
Electronic files are stored in Filekeeper.
File Name: WBN_Summary_Files_Rev. 1.zip Document ldentifier: 323197 tr Microfiche/eFiche Page: 9 TVA 40533 [10-2008]
NEDP-2 -4 110-20-2008I
Calculation No. MDN-000-999-2008-01 51 Rev: 001 Plant: WBN Unit 0 Page: 10
Subject:
WBN PROBABILISTIC RISK ASSESSMENT -
SUMMARY
1.0 Purpose This calculation documents the summary of the results Watts Bar Nuclear Plant (WBN)
Units 1 and2 PRA model.
As part of the conversion of the WBN PRA from a RISKMAN platform to a CAFTA platform, the analyses supporting the PRA were completely redone. All documentation for the lnternal Events (ASME/ANS RA-Sa-2009 Part 2, Reference 1) and lnternal Flooding (ASME/ANS RA-Sa-2009 Part 3, Reference 1) PRA has been upgraded to meet the requirements of Regulatory Guide 1.200 Rev. 2 (Reference 2). The WBN PRA now meets at Ieast category 2 of the requirements of the ASME/ANS Standard and Regulatory Guide '1.200, R2, with respect to interna! events. However, fire and external events such as seismic events, high winds, and external floods are not evaluated in the WBN model.
The original R0 CAFTA model has been updated to revision 1. This revision of the Summary Notebook documents the changes which were made.
2.0 References and Acronyms 2.1 References
- 1. ASME/ANS RA-Sa-2009, Addenda to ASME/ANS RA-S-2008, Standard for Level 1/Large Early Release Frequency Probabilistic Risk Assessment for Nuclear Power Plant Applications.
- 2. Regulatory Guide 1.200, An Approach for Determining the TechnicalAdequacy of Probabilistic Risk Assessment Results for Risk lnformed Activities, Rev 2.
- 3. NEI 05-04, Process for Performing lnternal Events PRA Peer Reviews using the ASME/ANS PRA Standard, Rev. 2.
- 4. EPRI-TR-1021086, Pipe Rupture Frequencies for lnternal Flooding PRAs, Revision 2, November 2010
- 5. SPP-9.11, NPG Standard Programs and Processes, Probabilistic Risk Assessment (PRA) Program, Rev. 0.
- 6. NEDP-2, NPG Department Procedure, Design Calculation Process Control, Rev.14.
- 7. NEDP-26, NPG Department Procedure, Probabilistic Risk Assessment (PRA),
Rev.2.
Calculation No. MDN-000-999-2008-01 51 Rev: 001 Plant: WBN Unit 0 Page:11
Subject:
WBN PROBABILISTIC RISK ASSESSMENT -
SUMMARY
- 8. NUREG/CR-6928, U.S. Nuclear Regulatory Commission, Industry-Average Performance for Components and lnitiating Events at U.S. Commercial Nuclear Power Plants, February 2007.
- 9. NUREG/CR-5497, Common-Cause Failure Parameter Estimations, October 1998.
- 10. Not used.
- 11. Regulatory Guide 1.174, "An Approach For Using Probabilistic Risk Assessment ln Risk-lnformed Decisions On Plant-Specific Changes To The Licensing Basis" November 2002.
- 12. Regulatory Guide 1.177, An Approach for Plant-Specific, Risk-lnformed Decision-making: Technical Specifications, August 1998.
- 13. LTR-RAM-I!-09-084, RG 1.200 PRA Peer Review Against the ASME/ANS PRA Standard Requirements for the Wafts Bar Nuclear Power Plant Probabilistic Risk Assessment, (B45 100125 001).
- 14. WCAP-16141, Rev 0, RCP Sea! Leakage PRA Model lmplementation Guidelines for Westinghouse PWRs.
1 5. CN-N UC-WBN-MEB-MDN-000-00 1 -2008-0122, WBN Probabilistic Risk Assessment - Main Steam System, Rl 1 6. CN-NUC-WBN-M EB-MDN-000-002-2008-0123, WBN Probabilistic Risk Assessment - Condensate and Feedwater System, R1 17. CN-NUC-WBN-MEB-MDN-000-003-2008-0124, WBN Probabilistic Risk Assessment - Auxiliary Feedwater System, R4 1 8. CN-NUC-WBN-MEB-MDN-000-003-2008-0125, WBN Probabilistic Risk Assessment - Steam Generator lsolation System, R0 1 9. CN-NUC-WBN-MEB-MDN-000-032-2008-0126, WBN Probabilistic Risk Assessment - Plant Compressed Air System, Rl
- 20. CN-NUC-WBN-MEB-MDN-000-062-2008-0127, WBN Probabilistic Risk Assessment - Chemical and Volume Control System, R3 21. CN-NUC-WBN-MEB-MDN-000-062-2008-0128, WBN Probabilistic Risk Assessment - RCP Seal lnjection and Thermal Barrier Cooling, R0
- 22. CN-NUC-WBN-MEB-MDN-000-063-2008-01 29, WBN Probabilistic Risk Assessment - Safety lnjection System, R0
Calculation No. MDN-000-999-2008-01 51 Rev: 001 Plant: WBN Unit 0 Page: 12
Subject:
WBN PROBABILISTIC RISK ASSESSMENT -
SUMMARY
- 23. CN-N UC-WBN-M EB-MDN-000-067 -2008-0130, WBN Probabilistic Risk Assessment - Essential Raw Cooling Water System, R5
- 24. CN-NUC-WBN-MEB-MDN-000-068-2008-01 31, WBN Probabilistic Risk Assessment - Pressurizer Power-Operated Relief Valves and Safety Valves System, R0
- 25. CN-NUC-WBN-MEB-MDN-000-070-2008-01 32, WBN Probabilistic Risk Assessment - Component Cooling System, R2
- 26. C N-N U C-WB N-M E B-M D N-000-07 2-2008-0133, WBN Probabil istic Risk Assessment - Containment Spray System, R0 27. CN-NUC-WBN-MEB-MDN-000-074-2008-01 34, WBN Probabilistic Risk Assessment - Residual Heat Remova! System, R2
- 28. CN-NUC-WBN-MEB-MDN-000-099-2008-01 35, WBN Probabilistic Risk Assessment - Reactor Protection System, R0
- 29. CN-NUC-WBN-MEB-MDN-000-099-2008-01 36, WBN Probabilistic Risk Assessment - Engineered Safety Features Actuation System, R0
- 30. CN-NUC-WBN-MEB-MDN-000-999-2008-01 37, WBN Probabilistic Risk Assessment - Electric Power System, R3 31. CN-NUC-WBN-MEB-MDN-000-999-2008-01 38, WBN Probabilistic Risk Assessment - LOOP Non-Recovery Probabilities, R1
- 32. CN-NUC-WBN-MEB-MDN-000-999-2008-01 39, WBN Probabilistic Risk Assessment - Containment System, R0
- 33. CN-NUC-WBN-MEB-MDN-000-999-2008-01 40, WBN Probabilistic Risk Assessment - lnitiating Events Analysis, R2
- 34. CN-NUC-WBN-M EB-MDN-000-999-2008-01 41, WBN Probabilistic Risk Assessment - Accident Sequence Analysis, R1
- 35. CN-N UC-WBN-MEB-MDN-000-999-2008-01 42, WBN Probabilistic Risk Assessment - Success Criteria, R3
- 36. CN-NUC-WBN-MEB-MDN-000-999-2008-01 43, WBN Probabilistic Risk Assessment - Systems Analysis Summary, R1 37. CN-NUC-WBN-MEB-MDN-000-999-2008-01 44, WBN Probabilistic Risk Assessment - Human Reliability Analysis, R3
Calculation No. MDN-000-999-2008-01 51 Rev: 001 Plant: WBN Unit 0 Page: 13
Subject:
WBN PROBABILISTIC RISK ASSESSMENT -
SUMMARY
- 38. CN-NUC-WBN-MEB-MDN-000-999-2008-01 45, WBN Probabilistic Risk Assessment - Data Analysis, R4
- 39. CN-NUC-WBN-MEB-MDN-000-999-2008-01 46, WBN Probabilistic Risk Assessment - lnternal Flooding Analysis, R2
- 40. CN-NUC-WBN-MEB-MDN-000-999-2008-01 48, WBN Probabilistic Risk Assessment - Level 2 (LERF) Analysis, R3 41. CN-NUC-WBN-MEB-MDN-000-999-2008-01 49, WBN Probabilistic Risk Assessment - Loss of Offsite Power Frequency Analysis, R0
- 42. CN-NUC-WBN-MEB-MDN-000-999-2008-01 50, WBN Probabilistic Risk Assessment - lnterfacing Systems LOCA Analysis, R0
- 43. CN-NUC-WBN-M EB-MDN-000-999-2008-01 53, WBN Probabilistic Risk Assessment - Thermal Hydraulics Analysis, Leve! !, R1
- 44. CN-NUC-WBN-MEB-MDN-000-999-2008-01 47, WBN Probabilistic Risk Assessment - Quantification, R4
- 45. CN-N UC-WBN-MEB-MDN-000-999-2009-01 62, WBN Probabilistic Risk Assessment - Sensitivity and Uncertainty, R2 2.2 Acronyms The following acronyms are used in this document:
AC Alternating Current ANS American Nuclear Society ASME American Society of Mechanical Engineers ATWS Anticipated Transient Without SCRAM CAFTA Computer Aided Fault Tree Analysis System CCF Common Cause Failure CCF Common Cause Failure CCS Component Cooling System CCW Condenser Circulating Water CDF Core Damage Frequency CET Containment Event Tree CPNPP Comanche Peak Nuclear Power Plant
Calculation No. MDN-000-999-2008-01 51 Rev: 001 Plant: WBN Unit 0 Page:14
Subject:
WBN PROBABILISTIC RISK ASSESSMENT -
SUMMARY
DC EDG EPRI ERCW F&O FMEA F-V GTRAN HEP HFE HPFP HRA IF ISLOCA LERF LLOCA LOCA LOOP MAAP MGL MLOCA MOR NEI PRA RAW RCP RCW SGTR SLOCA SLOCAV SR Direct Current Emergency Diesel Generator Electric Power Research lnstitute Essential Raw Cooling Water Fact and Observation Failure Modes and Effects Analysis Fussell - Vesely General Transient Human Error Probability Human Failure Event High Pressure Fire Protection Human Reliability Analysis lnternal Flooding lnterfacing Systems LOCA Large Early Release Frequency Large LOCA Loss of Coolant Accident Loss of Offsite Power Modular Accident Analysis Program Multiple Greek Letter Medium LOCA Model of Record Nuclear Energy Institute Probabilistic Risk Assessment Risk Achievement Worth Reactor Coolant Pump Raw Cooling Water Steam Generator Tube Rupture Small LOCA Very Small LOCA Supporting Req uirement
Calculation No. MDN-000-999-2008-0 1 51 Rev: 001 Plant: WBN Unit 0 Page: 15
Subject:
WBN PROBABILISTIC RISK ASSESSMENT -
SUMMARY
SSBI Secondary Side Break lnside Containment SSBO Secondary Side Break Outside Containment SSC Structure, System, or Component T&M Test and Maintenance TLPCA Total Loss of Plant Compressed Air TVA Tennessee Valley Authority WBN Watts Bar Nuclear 3.0 Design Input All inputs to this calculation are listed in section 2.1. The documentation requirements for the PRA are provided in Section 3.6 of NEDP-26 (Reference 7). Table 10 provides a listing and description of WBN PRA model files. Attachment B of this calculation documents the Model of Record (MOR).
4.0 Assumptions Assumptions used in the development and quantification of the WBN PRA are listed in the PRA model documentation (References 15 through 45).
The dual unit model was updated based on the as-built, as-operated configuration of the plant as of April 30,2013. Significant modifications to Unit 2 intended for completion prior to unit startup were also included. lt was assumed that no new significant modifications will be developed for unit 2 prior to startup.
5.0 Special Requirements/Limiting Gonditions None 6.0 Computations and Analyses The following sections provide a summary of the changes that were made to the PRA since the last revision and a summary of the results of the PRA quantification.
6.1 Model Development 6.1.1 Initiating Events The initiating event analysis has been updated to include current industry generic data, recent plant events and multi-unit initiators. The scope of this analysis included: 1) a review of all initiators in the RISKMAN model to ensure applicability, 2) resolution of previously identified problems, 3) a review of common initiators that could result in
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challenging both units, 4) the Bayesian updating of the initiating event frequency distributions, 5) the development of support system initiating event fault trees, and 6) the development of an updated lnitiating Event Notebook (Reference 33) and a Loss of Offsite Power (LOOP) Frequency Notebook (Reference 41). Flooding initiating events are identified in the lnternal Flooding Analysis Notebook (Reference 39). lnterfacing LOCA initiating events are identified in the ISLOCA Frequency Notebook (Reference 42).
6.1.1.1 New lnitiators Table 1 provides a listing of all initiators in the 2-unit WBN PRA CAFTA model. Where applicable, the equivalent RISKMAN initiator identifier is also given in Table 1. No RISKMAN identifiers are listed for the new initiators that have no RISKMAN model equivalent. Note that the RISKMAN R4 model did not address unit 2. lnternal flooding initiators were expanded from 6 to 133. lnterfacing System LOCA initiators were expanded from 2 to 24. One new transient initiator, Total Loss of Plant Compressed Air (TLPCA), was added.
No new initiators were identified for the Revision 1 CAFTA model.
6.1.1.2 lnitiators Removed from the Model No lnitiators were removed from the model.
6.1.1.3 Updates to Support System lnitiating Event Fault Trees Support system initiating event fault trees were built for the following initiating events:
. Partial Loss of ERCW o Total Loss of ERCW
. Loss of Train A CCS o Total Loss of CCS o Loss of 4 125Y DC busses
. Loss of8 120VAC busses The support system initiator fault trees are described in detai! in their system notebooks (References 23,25, and 30). Models for the unit 2 AC and DC busses are new to the CAFTA R0 analysis.
The following model changes were made for Revision 001:
o AFW 1-51 (trip and throttle) valves added. Note that this could be considered to be subsumed in the TDAFWP but the valve was modeled separately at the request of the station Maintenance Rule / MSPI coordinator, to facilitate data tracking and risk monitoring. Use of generic TDAFWP failure data as an input to the data evaluation may be slightly conservative as a result.
o RHR 74-12 and -24 (minimum flow) valves added o Data updated
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. Logic for vital inverters and battery chargers enhanced (see Electric Power Notebook for details) o DG ERCW supply valves changed from locked open to closed, required to open for DG success
. ERCW model enhancements (See ERCW notebook for details).
. CCS model enhancements (See CCS Notebook for details) o Minor changes to HRA preinitiators (See HM Notebook for details) o Revised HRA dependency approach to retain individual HEPs in cutsets
. Added N2 supply to AFW LCVs and PCVs 6.1.1.4 Updates to lE Frequencies from Generic and Plant Specific Data The generic initiating event frequencies used in the WBN PM have been updated as described in Section 6.3.2 of the lnitiating Events Notebook (Reference 33). The plant specific data used for the update is given in Table 2. The prior and posterior initiating event frequencies are provided in Table 3. Bayesian updating was not used to calculate the frequencies for flooding initiators or ISLOCA initiators.
6.1.1.5 Gomparison of lE Frequencies A comparison of initiating event frequencies between the Riskman R4 mode! and the CAFTA R0 model is provided in Table 4.
6.1.2 Accident Sequences Analysis The level 1 accident sequence analysis models, chronologically (to the extent practical),
the different possible progressions of events (i.e., accident sequences) that can occur from thEstart of the initiating event to either successful mitigation or core damage. The accident sequences account for the systems that are used (and available) and operator actions performed to mitigate the initiator based on the defined success criteria and plant operating procedures (e.9., plant emergency and abnormaloperating instructions) and training. The availability of a system includes consideration of the functional, phenomenological, and operationa! dependencies and interfaces between the various systems and operator actions during the course of the accident progression. A set of plant damage states were defined to account for important conditions that may affect containment response and possible offsite releases after a severe accident event.
These plant damage states, listed in Table 5, provide the interface between the Level 1 PRA models and the Level 2 PRA model. Licensed operators were interviewed as part of this process to ensure reasonable scenarios and corresponding conditions were modeled.
The accident sequences analysis was revised for the WBN PRA conversion from RISKMAN to CAFTA. The initiating events were grouped into classes that could be evaluated collectively. For each functiona! group of initiating events, an event tree model was developed that defines the possible plant responses, mitigating system functions, and operator actions that determine the event sequence progression.
A total of 10 event trees were developed for the WBN PRA:
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o LLOCA - Large LOCA o MLOCA - Medium LOCA
. SLOCA - Small LOCA o SLOCAV - Very Small LOCA o SSBI - Secondary Side Break lnside Containment o SSBO - Secondary Side Break Outside Containment
. GTRAN - Generaltransient
. SGTR - Steam Generator Tube Rupture o ATWS - Anticipated Transient Without SCRAM o ISLOCA - lnterfacing Systems LOCA These event trees are shown in Figures 1 through 10, respectively. Linking between the initiating events and the event trees is provided in Table 6.
Accident sequence models did not change in CAFTA model revision 1.
6.1.3 Success Criteria The success criteria analysis was revlsed for the WBN PRA conversion from RISKMAN to CAFTA. Success criteria analysis determines the minimum requirements for each function (and ultimately the systems used to perform the functions) used to prevent core damage (or to mitigate a release) given an initiating event. The requirements defining the success criteria are based on acceptable engineering analyses that represent the design and operation of WBN. Functional success criteria are dependent on the initiator and the conditions created by the initiator. The computer codes used for developing the success criteria are validated and verified for both technical integrity and suitability to assess plant conditions for the reactor pressure, temperature, and flow range of interest, and the phenomena of interest. Calculations are performed by personnel who are qualified to perform the types of analyses of interest and are wel! trained in the use of the codes.
The objectives of the success criteria element are to define the plant-specific measures of success and failure that support the other technical elements of the PRA in such a way that overall success criteria are defined. Success criteria are defined for critical safety functions, supporting systems, structures, and components (SSCs) and operator actions necessary to support accident sequence development.
During risk model development, existing safety analyses were reviewed, and selected thermal hydraulic analyses were performed to establish realistic success criteria for the mitigating systems and operator actions that are modeled in the PRA. ln some cases, conservative success criteria may be used to simpliff the models or their supporting analyses when the degree of conservatism does not have an important impact on the overall PRA results.
The success criteria are documented in detail in the Success Criteria notebook (Reference 35). Tables 7 through 16 provide a summary of the success criteria for
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each of the event trees. Tables 17 through 22 provide a comparison of success criteria between WBN PRA and the Comanche Peak Nuclear Power Plant (CPNPP) PRA.
6.1.3.1 Summary of Success Criteria Changes Based on a review of the documentation for the RISKMAN model, there were no significant changes in the success criteria previously used for the WBN PRA. No changes to success criteria were made for CAFTA model revision 1.
6.1.3.2 MAAP Analyses All thermal hydraulics calculations used as the basis for the success criteria were updated (or re-run) and documented in the Thermal Hydraulics Notebook (Reference 34). Table 23 provides a listing of MAAP runs. The sensitivity of core damage timing with respect to the size of RCP seal leakage is shown in Table 24. Table 25 provides the conditional probability of various size RCP seal leaks, taken from WCAP 16141 (Reference 14). Table 26 and Table 27 provide the sensitivity of timing to high pressure and low pressure recirculation for a variety of conditions and LOCA sizes.
!n addition, MAAP runs were executed to determine the sequence timing for the Human Reliability Analysis (HRA). A summary of these results is provided in Table 28.
6.1.4 Systems Analysis All systems that are required for accident mitigation and those systems supporting accident mitigating systems have been re-analyzed as part of the conversion from RISKMAN to CAFTA. Each system notebook is documented in a separate calculation, References 15 through 32, as Iisted in Table 29. The analysis for the Raw Cooling Water (RCW) System is documented in an appendix to the ERCW System notebook (Reference 23), and the analysis for the Condenser Circulating Water (CCW) System and Condenser Vacuum System is documented in an appendix to the Condensate and Feedwater System Notebook (Reference 16); these are new system analyses. There are two calculations pertinent to Electric Power, the system analysis (Reference 30),
and the Electric Power Recovery Notebook (Reference 31). The System Summary Notebook, (Reference 36) provides information common to the system analyses, such as model naming conventions, notebook format and content requirements and generic system assumptions.
6.1.4.1 Walkdowns Each system modeled in the PRA was walked down by a group of PRA analysts to evaluate
. Component location and operational status; o Environmental considerations such as heat sources, ventilation, and steam/humidity sources; o Considerations for manual operation; and o Physical characteristics of the room/area.
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The walkdowns are documented in Appendix A of the individual system notebooks.
6.1.4.2 System Engineer Review and Interviews Each system notebook was reviewed by the responsible system engineer(s).
Subsequently, the PRA analysts interviewed the system engineers. The purpose of the interview is as follows:
o Ensure system modeling in the PRA is consistent with the as-built, as-operated plant (SY-A4) o Ensure potential initiating events have not been overlooked (!E-AO) o Ensure system operating experience is properly considered and documented in the PRA (lE, DA)
The interviews are documented in Attachment A of each system notebook.
6.1.4.3 Design Changes lmpacting PRA The new CAFTA model included system engineer review and operator interviews to ensure that it was developed to reflect the as-built, as-operated plant. Future revisions of this document will included a discussion of design changes that require changes to the model.
The following model changes were made for Revision 001:
. AFW 1-51 (trip and throttle) valves added. Note that this could be considered to be subsumed in the TDAFWP but the valve was modeled separately at the request of the station Maintenance Rule / MSPI coordinator, to facilitate data tracking and risk monitoring. Use of generic TDAFWP failure data as an input to the data evaluation may be slightly conservative as a result.
o RHR 74-12 and -24 (minimum flow) valves added o DG ERCW supply valves changed from locked open to closed, required to open for DG success
. Revised HRA dependency approach to retain individual HEPs in cutsets 6.1.5 Data Analysis The objectives of the data analysis are to provide estimates of the parameters used to determine the probabilities of the basic events representing equipment failures and unavailabilities modeled in the PRA. Such parameters include the following:
o Failure rates
. Unavailability due to test and maintenance
. Common Cause Failure (CCF) Multiple Greek Letter (MGL) parameters.
The data analysis is documented in the Data Analysis Notebook (Reference 39).
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6.1.5.1 Unreliability Data The unreliability (or failure rate) data are based on generic industry data that has undergone Bayesian updating with plant specific data. Plant specific data for the period 11112003 to 413012013 was evaluated and used as input to the Bayesian analysis. A screening process was implemented to determine whether the generic, updated, or plant specific data should be used for the analysis. Table 30 provides a listing of failure data for which plant specific failure data was collected. Table 31 provides a comparison of failure data between the RISKMAN R4 model and the CAFTA R0 model. For Revision 1 of the CAFTA model, data was updated through 413012011. Revision 1 represents an incremental change from Revision 0, therefore comparison tables between revisions are not required.
6.1.5.2 Unavailability Data The unavailability data is based on plant-specific data collected in support of the Maintenance Rule or derived from other plant records, generic industry data, or estimates from plant personne! such as system engineers or operations staff. Plant specific data is the preferred method for determining unavailabili$ since it represents historical equipment unavailability. Plant maintenance unavailability data is based on the same time period as the failure data,11112003 to 413012013. Generic industry data from NUREG/CR-6928 (Reference 8) was used for components for which no plant specific data was available. lf no plant specific or generic industry data were available, estimates from plant personnel such as system engineers or operations staff were used.
Table 32 provides a listing of unavailability data for which plant specific data was collected. Table 33 provides a comparison of unavailability parameters between the RISKMAN R4 model and the CAFTA R0 model. Revision 1 of the CAFTA model represents an incremental change from Revision 0, therefore comparison tables between these revisions are not required.
6.1.5.3 Gommon Cause Data Components of similar manufacture and functions are subject to CCF. Common cause failure can result in failure of a system when identica!, non-diverse, and active components are used to provide redundancy. Failure of two or more components in a common cause group can occur if they are of the same design, perform the same function, share the same installation and maintenance procedures, and are located in the same location or environment.
ln the conversion of the WBN PRA from a RISKMAN model to a CAFTA model, the Multiple Greek Letter (MGL) methodology, described in NUREG/CR-5485, was retained. MGL factors were assigned to each CCF group and CAFTA automatically calculated the probability of the CCF basic events using equations based on the group size and the number of failed components. In a few instances, such as for system models to determine initiating event frequencies, specific basic events were inserted into the fault tree model to capture CCF probabilities.
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The CCF probabilities for the WBN PRA were conservatively calculated assuming that alltesting is performed on a non-staggered testing. The MGL factors were converted from alpha values provided in WCAP-16672-P via formulas provided in NUREG/CR-5485. This is a different data source than used for the RISKMAN R4 model. ln addition, no Bayesian updating of MGL factors was performed. Table 34 provides a list of CCF groups and associated MGL factors. Table 35 provides a comparison of MGL factors between the CAFTA R0 model and the RISKMAN R4 model.
The common cause analysis is documented in the Data Analysis Notebook (Reference 38).
6.1.6 Human Reliability Analysis The purpose of the HRA is to identify human interactions that play a role in the accident sequences, and to provide an estimate of the probabilities for failure events corresponding to those interactions. This analysis includes pre-initiators and post initiators. The HRA for the WBN PRA was revised and is documented in Reference 37.
Table 36 provides a list of the pre-initiator Human Failure Events (HFEs) and associated probabilities. Table 37 provides a Iist of the post-initiator HFEs. Table 38 provides a list of the post-initiator HFEs associated with recovery from flooding events. Table 39 provides a summary comparison of Human Error Probabilities (HEPs) between the CAFTA R0 model and the RISKMAN R4 mode!. Revision 1 of the CAFTA model represents an incremental change from Revision 0, therefore comparison tables between these revisions are not required.
6.1.7 lnternal Flooding The internal flooding (lF) analysis for the WBN PRA was updated based on the new flood frequencies provided in EPRI-TR-1021086 (Reference 4), and is documented in the lnternal Flooding Analysis Notebook, Reference 39. That calculation documents the development and application of the internal flooding analysis consistent with the guidance provided in the ASME PRA Standard RA-Sa-2009 (Reference 1).The scope of the flooding events covered includes allfloods originating within the plant boundary. lt does not include floods resulting from external events (e.9., weather, offsite events such as upstream dam rupture, etc.).
The IF-PRA methodology is organized into two major phases, as shown in Figure 11. ln the first phase of !F-PRA, Qualitative Analysis, the information that is needed for the lF-PRA is collected and the initial qualitative analysis tasks are performed. There are four key tasks that are completed in this phase; (Task 1) identification of flood areas and SSCs, (Task 2) identification of flood sources, (Task 3) performance of a plant walkdown, and (Task 4) completion of a qualitative screening evaluation of plant locations.
!n the second phase of !F-PRA, plant locations which have not been screened out are addressed in six separate tasks that comprise the quantitative evaluation phase of lF-PRA. These tasks are organized around the key steps in defining flood scenarios and quantifying their impacts in the PRA model in terms of their contributions to CDF and
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LERF. These steps include (Task 5) the definition of flood scenarios in terms of (Task 6) flood initiating events, (Task 7) the consequences of the flood on SSCs, (Task 8) human actions to mitigate the consequences of the flood and to control the plant, and (Task 9) the interfacing of the flood scenario with the PRA event tree/fault tree logic. Once the scenarios have been properly characterized, this phase also addresses (Task 10) the quantification of the flood initiating event frequency, CDF, and LERF.
Table 40 provides a summary of flooding sources. Table 4'l and Figure 12 provide a sample propagation calculation. Tables 42 through 46 provide the results of the qualitative screening assessment. Table 47 provides a description and frequency of the internal flooding initiators. Table 48 provides a description of the effects of the flooding initiators. Table 49 provides a summary of the HEPs that were modified to accommodate the flooding analysis. Figures 13 through 16 provide a summary of the CDF and LERF results of the flooding analysis.
6.1.7.1 Walkdowns Several plant walkdowns were performed to assess the plant for partitioning into flood zones, characterize the flood sources in each zone, examine the flow propagation paths between flood areas, and determine the susceptibility of PRA equipment to flood and spray effects. Table 50 provides a sample walkdown data sheet.
6.1.7.2 Raw Water Piping in the Auxiliary Building Pipe failure frequencies calculated for risk significant raw water piping in the Auxiliary Building are based on leak-before-break methodology. lt is assumed that WBN will implement a monitoring program for risk significant raw water piping in the Auxiliary Building similar to that employed at SQN.
6.1.8 Large Early Release Frequency Analysis The Level 2 Analysis was revised as part of the conversion from a RISKMAN model to a CAFTA model, and is documented in Reference 40.
The Level 2 Analysis describes the process used to identify core damage sequences that could lead to large early fission product releases to the environment and therefore contribute to the WBN Large Early Release Frequency (LERF).
The LERF sequences are identified through the development of a containment event tree (CET). The Level 2 Analysis documents the development of the CET and the process used to quantify LERF using the CET; results of the LERF quantification are contained in the PRA Quantification Notebook (Reference 44). Table 23 provides a listing of MAAP runs.
The CET is shown in Figure 17. The structure of the CET has been formulated to include the following features for the assessment of LERF:
o to properly represent the time sequence of events and to divide the CET into major time periods;
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o to incorporate all important system, human and phenomenological occurrences including possible recovery; o to maintain a simplified representation; o to preserve the nature of the challenge throughout the analysis; o to explicitly recognize the effect of postulated containment failure modes; o to allow the identification of recovery and repair actions that can terminate or mitigate the progression of a severe accident; and o to categorize the end-states of the resulting sequences into groups that can be assessed for their affect on public safety. This grouping has been simplified to meet Reg. Guide 1.174 requirements.
The CET end-states are as follows:
o INTACT - an intact containment with no release to the environment o BLERF - Large early release via bypass of the containment
. ILERF - Large early release via failure of isolation of the containment o LLERF - Large early release during low pressure sequences o HLERF - Large early release during high pressure sequences o LATE - Iate release
. BSERF - Small early release via bypass of the containment o ISERF - Small early release via failure of isolation of containment
. SERF - Small early release via recovery of AC power o PI-SGTR - Pressure induced steam generator tube rupture o TI-SGTR - Temperature induced steam generator tube rupture.
The Level 2 analysis interfaces with the Level 1 accident sequence analysis through the appropriate definition of a set of plant damage states. These states are the endpoints of the sequences in the Level 1 portion of the event trees and the initiating events for the CET.
6.1.9 Quantification The WBN PRA CAFTA model was quantified after the conversion from a RISKMAN model. The Quantification is documented in Reference 44.
The input files used for the quantification are listed in Table 51 and are stored as zip fifes in Filekeeper. Refer to the computer storage information sheet of Referen ce 44 for file names and Filekeeper identification numbers.
6.1.10 Maintenance & Update/Configuration Control (MU)
The TVA process for controlling updates to the PRA is documented in TVA procedures SPP-9.11, "The Probabilistic Risk Assessment Program" and NEDP-26, "Probabilistic Risk Assessment".
SPP-9.11 (Reference 5) covers the management of PRA applications, periodic updates, and interdepartmental PRA documentation. This procedure provides definitions for PRA model update, PRA model application, and PRA evaluation. This procedure also defines
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responsibilities of other departments such as operations and system engineering for review of the PRA.
NEDP-26 (Reference 7) describes the process used by the PRA staff to perform applications, model updates and PRA model maintenance and review. The terms PM upgrade and maintenance are defined in the ASME standard (Reference 1). The procedure requires that updates be completed at least once every other fuel cycle (for the lead unit at multiunit sites) or sooner if estimated cumulative impact of plant configuration changes exceeds +l-10o/o of CDF or LERF. Changes in PRA inputs or discovery of new information are evaluated to determine whether such information warrants PRA update. ltems exceeding the above threshold are tracked in the Corrective Action Program. Changes that do not meet the threshold for immediate update are tracked in the PM Model Open ltems Database. PRA updates follow the guidelines established by the ASME Standard for a minimum of a Category !l assessment.
NEDP-26 also defines the requirements for PRA documentation of the model of record (MOR) and PRA applications. The MOR is composed of the 1) PRA computer model and supporting documentation,2) MAAP model and supporting documentation, and 3) other Supporting Computer Evaluation Tools (e.9., UNCERT, EPRI HRA Calculator, etc). The purpose of the PRA MOR is to provide a prescriptive method for quality, configuration, and documentation control. PRA applications and evaluations are referenced to a MOR and therefore the pedigree of PRA applications and evaluations is traceable and verifiable. NEDP-26 also specifies the requirements for independent review and periodic self assessments of the model.
After September 2008 all PRA notebooks modified will be converted to desirable calculations. The NEDP-2 (Reference 6) calculation process requires calculations to be prepared and independently checked and approved.
6.1.11Software The software packages used in the WBN PRA quantification are listed in Table 52.
6.1.12 Resolution of F&Os from Peer Review of the RISKMAN R4 Model The RISKMAN model R4 underwent a peer review by the Westinghouse (WOG) and received a total of 80 Facts and Observations (F&Os). The F&Os and current status are provided in Appendix A.
6.1.13 Resolution of F&Os from Peer Review of the CAFTA R0 model The WBN Units 1 and 2Internal Events PRA peer review was performed in November, 2009 at the TVA offices in Chattanooga, TN, using the process described in NEI 05-04 (Reference 3), the ASME PRA Standard (Reference 1), and Regulatory Guide 1.200 (Reference 2). A team of independent PRA experts from nuclear utility groups and PRA consulting organizations carried out these peer review certifications.
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The purpose of the peer review is to provide a method for establishing the technical adequacy of a PRA for the spectrum of potential risk-informed plant licensing applications for which the PRA may be used. The 2009 WBN PRA Peer Review provided a full-scope review of the technical elements of the interna! events, at-power PRA, including internal flooding. The PRA was not reviewed for fires, extemal flooding, seismic, high winds, or other external events.
This intensive peer review involved over two person-months of engineering effort by the review team and provides a comprehensive assessment of the strengths and limitations of each element of the PRA mode!. The review team determined that the WBN PRA meets, at capability category ll or greater,258 of a total of 326 supporting requirements (SRs), with 9 SRs determined to be not applicable. Table 53 provides a summary of the assessment results. A total of 112 F&Os were generated, consisting of 50 findings and 62 suggestions. All finding-level F&Os were addressed to at least the requirements of capability category ll; see related notebooks for details (i.e. For flooding F&Os, see the flooding notebook. For system F&Os, see the appropriate system notebook).
6.1.14 Major Ghanges from Riskman R4 model to the CAFTA R0 model The WBN Unit 1 PRA R4 (operating via Riskman software) underwent substantial revision including a change to the CAFTA software suite. The revised model is referred to as the CAFTA R0 model. Major differences are listed below.
o lnclusion of unverified Unit 2 model o Upgraded to address requirements of ASME/ANS M-Sa-2009 o Processed to comply with requirements of TVA procedure NEDP-2 (engineering calculations)
. Upgraded flooding analysis approach
. Expansion of flooding initiating events from 6 to 133
. Expansion of ISLOCA initiating events from 2 to 24 o Addition of TLPCA initiating event
. Expanded CCF coverage 6.2 Results 6.2.1 Core Damage Frequency Table 54 summarizes the CDF and LERF for each unit and the number of cutsets saved for each quantification. Table 55 provides a listing of the dominant accident sequences.
Table 56 provides the distribution of core damage sequences across the frequency range. Figure 18 provides a comparison of WBN CDF with that of otherWestinghouse plants. A listing of the top 100 cutsets is provided in Table 57 and Table 58 for unit 1 and unit 2, respectively.
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6.2.1.1 Total CDF with Uncertainty Analysis The CDF uncertainty analysis was performed using the UNCERT computer program.
Plots showing the uncertainty distributions are provided in Figure 19 and Figure 20.
6.2.1.2 Initiator Contribution to CDF The initiator contribution to CDF for each unit is shown graphically in Figure 21 and Figure 22 and in tabular form in Table 59 and Table 61. Table 60 provides a comparison of initiator contributions to unit 1 CDF between the CAFTA R0 and RISKMAN R4 models.
6.2.1.3 System lmportance to CDF The importance of systems to CDF was calculated using the SYSIMP computer code.
Table 62 provides the systems with a Fussel! - Vesely (F-V) importance greater than 0.5% for Unit 1 CDF, sorted on F-V importance. Table 63 provides the systems with a Risk Achievement Worth greater than 2 for Unit 1 CDF, sorted on Risk Achievement Worth (RAW). Table 64 provides the systems with a F-V importance greater than 0.5%
for Unit 2CDF, sorted on F-V importance. Table 65 provides the systems with a RAW greater than 2 for Unit 2 CDF, sorted on RAW.
6.2.1.4 Gomponent lmportance to CDF The importance of components to CDF was calculated using the SYSIMP computer code. Table 66 provides the components with a F-V importance greater than 0.5% for Unit 1 CDF, sorted on F-V importance. Table 67 provides the components with a RAW greater than 2 for Unit 1 CDF, sorted on RAW. Table 68 provides the components with a F-V importance greater than 0.5% for Unit 2 CDF, sorted on F-V importance. Table 69 provides the components with a RAW greater than 2 for Unit 2CDF, sorted on RAW.
Appendix C contains an Excel spreadsheet with a complete listing of component importance measures.
6.2.1.5 Operator Action lmportance to GDF The importance of operator actions to CDF was calculated using CAFTA and the CDF cutset files. Those operator actions with a F-V greater than O.5o/o ila listed in Table 70 and Table 72,for unit 1 and 2, respectively. Those operator actions with a RAW value greater than 2 are listed in Table 71 and Table 73, for unit 1 and 2, respectively.
6.2.1.6 Basic Event lmportance to CDF The importance of basic events to CDF was calculated using CAFTA and the CDF cutset files. Those basic events with a F-V greater than 0.5% are listed in TableT4 and Table 76, for unit 1 and 2, respectively. Those basic events with a RAW value greater than 2 are listed in Table 75 and Table 77, for unit 1 and 2, respectively.
Appendix C contains an Exce! spreadsheet with a complete listing of basic event importance measures.
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6.2.1.7 Test and Maintenance lmportance to CDF The importance of Test and Maintenance (T&M) events to CDF was calculated using CAFTA and the CDF cutset files. T&M events with a F-V greater than 0.5%
are listed in Table 78 and Table 80, for unit 1 and2, respectively. T&M with a RAW value greater than 2 are listed in Table 79 and Table 81, for unit 1 and 2, respectively.
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6.2.2 Large Early Release Frequency Table 54 summarizes the CDF and LERF for each unit and the number of cutsets saved for each quantification. Table 82 provides a listing of the dominant accident sequences.
Table 83 provides the distribution of large early release sequences across the frequency range. Figure 23 provides a comparison of WBN LERF with that of other Westinghouse plants. Figure 24 provides a comparison of WBN LERF with that of other Westinghouse plants with ice condenser containments. A listing of the top 100 cutsets is provided in Table 84 and Table 85 for unit 1 and unit 2, respectively.
6.2.2.1 Total LERF Uncertainty Analysis The LERF uncertainty analysis was performed using the UNCERT computer program.
Plots showing the uncertainty distributions are provided in Figure 25 and Figure 26.
6.2.2.2 Phenomena Gontribution to LERF The phenomena contribution to LERF for each unit is shown graphically in Figure 27 and Figure 28 and in tabular form in Table 86 and Table 87.
6.2.2.3 PDS Contribution to LERF The PDS contribution to LERF for each unit is shown graphically in Figure 29 and Figure 30 and in tabular form in Table 88 and Table 90. Table 89 provides the mapping between the PDSs of the level 1 analysis and the Bins of the level 2 analysis.
6.2.2.4 lnitiator Gontribution to LERF The initiator contribution to LERF for each unit is shown graphically in Figure 31 and Figure 32 and in tabular form in Table 91 and Table 93. Table g2 provides a comparison of initiator contributions to LERF between the CAFTA R0 and RISKMAN R4 models. Revision 1 of the CAFTA model represents an incrementa! change from Revision 0, therefore comparison tables between these revisions are not required.
6.2.2.5 System lmportance to LERF Table 94 provides the systems with a F-V importance greater than 0.5% for unit 1 LERF, sorted on F-V importance. Table 95 provides the systems with a RAW greater than 2 for unit 1 LERF, sorted on RAW. Table 96 provides the systems with a F-V importance greater than 0.5% for unit 2 LERF, sorted on F-V importance. Table g7 provides the systems with a RAW greater than 2 for unit 2 LERF, sorted on RAW.
6.2.2.6 Component lmportance to LERF Table 98 provides the components with a F-V importance greater than 0.5o/o for unit 1 LERF, sorted on F-V importance. Table 99 provides the components with a RAW greater than 2 for unit 1 LERF, sorted on RAW. Table 100 provides the components with a F-V importance greater than 0.5Yo for unit 2 LERF, sorted on F-V importance.
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Table 101 provides the components with a RAW greater than 2 for Unit 2 LERF, sorted on RAW.
6.2.2.7 Operator Action lmportance to LERF Those operator actions with a F-V greaterthan 0.5% are listed in Table 102 and Table 104, for unit 1 and 2, respectively. Those operator actions with a RAW value greater than 2 are listed in Table 103 and Table 105, for unit 1 and 2, respectively.
6.2.2.8 Basic Event lmportance to LERF Those basic events with a F-V greater than 0.5o/o are listed in Table 106 and Table 108, for unit 1 and 2, respectively. Those basic events with a RAW value greater than2 are listed in Table 107 and Table 109, for unit 1 and 2, respectively.
6.2.2.9 Test and Maintenance Importance to LERF Test and maintenance events with a F-V greater than 0.5% are listed in Table 110 and Table 112,for unit 1 and 2, respectively. Test and maintenance events with a RAW value greater than 2 are listed in Table 111 and Table 113, for unit 1 and 2, respectively.
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7.0 Supporting Graphics 7.1 Tables Tablp. fl
- lnitiating iEvents ood: Unit 1 AFW line break in general areas (and 737.0-A3) ood: AFW line break in room 692.0-A6 ood: AFW line break in room 692.0-A7 ood: Unit 1 AFW line break in general areas (and 737.O-AL?\\
ood: AFW line break in room 592.0-A25 ood: AFW line break in room 592.0-A26 lood: AFW line break in room 713.0-A19 FLAFWTI3Ab lood: AFW line break in room 713.0-A5 lood: AFW line break in room 737.A-As lood: AFW line break in room 737.O-A9 FLCRDMlF ood event: HPFP or RCW line break in room 782.0-AL lood event: HPFP or RCW line break in room 782.0-A3 FLCV61592A10 lood event induced by CVCS break in room 592.0-A10.
lood event induced by CVCS break in room 692.0-A9.
lood event induced by CVCS break in area 713.0-A0 (Unit 1)
FLCVCSLTL3A6 ood event induced by CVCS break in room 713.0-A5.
FLCVCSLTST ALO lood event induced by CVCS break in area 757.0-Al:O FLCVCSlPITS lood event induced by Unit 1 CVCS break in sealed pits.
FLCV62692A22 lood event induced by CVCS break in room 69?.0-A22.
lood event induced by CVCS break in room 592.0-A23.
FLCV627r3AO ood event induced by CVCS break in area 713.0-A0 (Unit 2) ood event induced by CVCS break in room 713.0-A19.
FLCVCS2PITS ood event induced by Unit 2 CVCS break in sealed pits.
lood event induced by DWS line break in room 713.0-A19 FLDWSTL3A6 lood event induced by DWS line break in room 713.0-A5 ood event induced by DWS in the common areas of the Auxiliary uilding (multip ood event induced by unisolated ERCW break associated with FLERCW1AESFRCF F room cooling tr ajor flood event induced by unisolated ERCW break associated FLERCW1AESFRCMF ith ESF room coo!
ood event induced by unisolated ERCW break associated with
%OFLERCWlBESFRCF F room cooling tr ajor flood event induced by unisolated ERCW break associated LAFW1592A6 FLAFW2692A25 FIAFW2692A26 FLAFW713A19 FLAFW737A9
%OFLCRDM2F FLCV61592A9
%0F1CV61713A0 FLCV62692A23 FLCVCSZ7L3AL9 FLDWS713A19
%OFLDWSAB
%OFLERCWlBESFRCM F ith ESF room cool
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Table 'l - lhitiating Events A IDENT]FIER ESGRIPTION Flood event induced by unisolated ERCW break associated with i
,l F room cooling tr i
ajor flood event induced by unisolated ERCW break associated h ESF room cool I
Flood event induced by unisolated ERCW break associated with i
ESF room cooling tr Major flood event induced by unisolated ERCW break associated I ith ESF room cool i
LERCW692A25 Flood: ERCW break - supply header 2A in room 692.0-A25.
ood event induced by ERCW line break: discharge header B (AFW i
%OFLERCW592A25F pump room)
Flood event induced by ERCW line break: discharge header A (AFW i TD pump rooml i
Major flood event induced by ERCW line break: discharge header A i LERCW592A5MF AFW TD pump ro i
Flood: ERCW break - supply header 18 in room 692.0-A7.
I Flood: ERCW break - supply header 2A in room 713.0-A19.
lood: ERCW break - supply header 18 in room 713.0-A28.
FLERCW7L3A29 ood: ERCW break - supply header 2A in room 713.0-A29.
i FLERCWTL3A6 ood: ERCW break - supply header 18 in room 713.0-A5.
ood: ERCW break - supply header 18 in room 737.0-A5.
lood: ERCW break - supply head er 2A in room 737.0-Ag.
lood event induced by unisolated ERCW break at elevation 676' of i uxitiary Buil i
Flood event induced by unisolated ERCW break at etevation 676' ofi uxiliary Buil l
i Flood event induced by unisolated ERCW break at elevation 676' of Auxiliary Buil i
Ftood event induced by unisolated ERCW break at etevation 675' of i RCWAB576F-28 uxiliary Buil i
ajor flood event induced by unisolated ERCW break in room i
%OFLERCWABST6MF-1A 76.0-A1 (ESF room co i
ajor flood event induced by unisolated ERCW break in room i
FLERCWABSTSMF-1B 76.0-A1 (ESF room co i
Major flood event induced by unisolated ERCW break in room 75.0-A1 (ESF room co Major flood event induced by unisotated ERCW break in room f
FLERCW592A5F FLERCWABGTSMF-2B FLERCW2AESFRCF FLERCW2AESFRCMF LERCW2BESFRCF LERCW2BESFRCMF FLERCW592A25MF LERCW692A7 FLERCW737A5 FLERCW737A9 FLERCWAB6T6F-1A FLERCWAB6TSF-18 LERCWAB57GF.2A FLERCWAB6TSMF-2A 76.0-A1 (ESF room co
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Table I - lnitiating-E fit$
AFTA IDENTIFIER LERCWDISBMF LERCWIPSA LERCWIPSB FLHELBO1A FLH ELBO1B LHPFP737A5F LHPFP737A9F
%OFLHPFPAB757A2 FLHPFPAB772A7 LHPFPABF FLH PFPI PS FLRCW737 ASF
%0FLRCW737A5MF LRCW757AL7 LRCW772A8 Flood event induced by ERCW line break in Control Building.
Flood event induced by ERCW line break: discharge header A Major flood event induced by ERCW line break: discharge header A i Flood event induced by ERCW line break: discharge header B i
ajor flood event induced by ERCW line break: discharge header B i ood event in ERCW Strainer room A lood event in ERCW Strainer room B ELB: CVCS line break in 713.0-A28 HELB: CVCS line break in 713.0-A29 HELB: CVCS line break in737.O-A7 HELB: CVCS line break in737.0-A8 Flood event induced by a HPFP line break in room 692.0-A25 i ood event induced by a HPFP line break in room 692.0-Al i
ood event induced by HPFP line break in room 737.A-AS event induced by HPFP line break in room 737.0-A9 Flood event induced by HPFP line break in room 713.0-A19 or 7L3.0-A2L Flood event induced by HPFP line break in room 713.0-A6 or 713.0- i Flood event induced by break of HPFP line in room 757.0-Az Flood event induced by break of HPFP line in room 757.}-AzL Flood event induced by break of HPFP line in room 757.o-A24 lood event induced by break of HPFP line in room 757.0-A5 ood event induced by break of HPFP line in room 772.0-AL0 ood event induced by break of HPFP line in room 772.0-A7
\\
oodeventinducedbyHPFPinthecommonareasoftheAuxiliary uilding (multi lood event induced by a HPFP line break in the Control Building I Flood event induced by a HPFP or RCW line break in room 711.0-E1 r
Flood event induced by rupture of RCW lines in room 737.0-A5 Major flood event induced by rupture of RCW lines in room 737.0- '
Flood event induced by rupture of RcW lines in room 737.0-A9 ood event induced by rupture of RCW line in room 757.0-AL7 ood event induced by rupture of RCW line in room 757.O-A9 ood event induced by rupture of RcW line in room 772.0-A8 Flood event induced by rupture of RcW line in room 772.0-A9 Flood event induced by RCW in the common areas of the Auxiliary
%OFLERCWCB
%OFLERCWDISAF
%OFLERCWDISAMF FLERCWDISBF FLHELBO2A
%OFLHELBO2B FLHPFP592A25F FLHPFP692 A7F LHPFPAB713A192LF
%OFLHPFPAB713A58F
%OFLHPFPAB757 AzL FLHPFPAB757A24 FLHPFPAB757A5 LHPFPABTTaALO FLH PFPCB FLRCW737AgF LRCW772A9
%OFLRCWABF
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Table {. Initiating Events LRWSTT692A7
%OFLRWST1713 A28 FLRWST1SIS FLRWST?TL3HX
%OFLRWST2AB575 FLRWST2ABSgzAL FLTBCST2MF FLTBSPRAY4 OSP-GR OSP-WI E8CRIPilOT..I uilding (multip Major flood event induced by RCW in the common areas of the liary Building (
Flood event induced by break in the lines from RWST 1 in room 92.4-A7 Flood event induced by break in the lines from RWST 1 in rooms 2.0-A8 or 713.0 Flood: break in the lines from RWST 1 in room 713.0-A28 Flood: rupture of the lines from RWST1 in any of the Unit 1 HX s at elevatio ood: Unisolated line break from RWST 1 - elevation 676' of uxiliary Building lood event induced by rupture of RWST I header in room 592.0-1 1
lood: SIS line break in any of the Unit 1 SIS pump room.
lood event induced by break in the lines from RWST 2 in rooms 92.0-A24 or 7L3.
Flood event induced by break in the lines from RWST 2 in room 92.0-A25 Flood: break in the lines from RWST 2in room 713.0-A29 Flood: rupture of the lines from RWST2 in any of the Unit 2 HX oms at elevatio Flood: unisolated line break from RWST 2 - elevation 676' of liary Building Flood event induced by rupture of RWST 2 header in room 592.0-ood: SIS line break in any of the Unit 2 SIS pump room.
ajor flood in the Turbine Building involving line break from CST1.
ajor flood in the Turbine Building invotving line break from CST2. i ajor flood in the Turbine Building ray event on 6.9kV board 1D and 2A ray event on common board 205 B ray event on air compressor D and sequencer ray event on dryers Loss of Offsite Power (Grid Related)
Loss of Offsite Power (Plant Centered)
Loss of Offsite Power (Weather lnduced) otal Loss of ERCW AFTA IDE}.ITIFIER LRCWABMF
%OFLRWST1592A8 FLRWST1713HX FLRWST1AB575 FLRWSTlAB592A1 LRWST2692A24 WST2592A25 FLRWSTZ7L3A29 FLTBSPRAYl-A-D
%OTLPCA otal Loss of Plant Compressed Air
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Table 1 - lnitiating Events A IDENTIFIER ESGRIPTION 1EXMFW 1FLCCS1AB592A7 1FLCCS7L3A28 1FLCCS737A5 lFLHELBAFW
%1FLRT!E
%lFLTBSPRAYI-A-B lFLTBSPRAYI-C-D ltsL-tEx107 lrsL-rEx15 ltsL-tEx20A 1ISL.IEX21 lISL-IEX33 lISL-RHRPMPSEAL lLDAAC lLDBAC otal Loss of Component Cooling System Unit 1 Loss of Component Cooling System Train 1A re Power Excursion CESSTVE LOCA (VESSEL RUPTURE) cessive Main Feedwater ood event induced by CCS line break (Train A) ood: CCS line break in room 692.0-A7
- unisolated break in CCS line in room 713.0-A28 Flood: CCS line break in room 737.0-A5 Flood event induced by CCS line break in room 757.0-A13 (Surge nk A).
HELB scenario induced by MSS supply to AFW line break. Unit 1 ntribution to reactor trip initiating event frequency due to pipe breaks - Uni pray event on Unit 1 5.9kV boards A and B pray event on Unit 1 6.9kV boards B and C pray event on Unit 1 5.9kV boards C and D pray event on U1 board 203A (480V TB) pray event on U1 board 2038 (480V TB) pray event on distribution board WBN-O-DPL -239-0001 Inadvertent Closure of all MSIVs I nadvertent Safety Injection ISLOCA RWST PIPING INITIATOR FLAG ISLOCA RHR Supply Line lnitiator Flag SL - LETDOWN LINE INITIATOR FIAG SLOCA RHR HOT LEG INITIATOR FLAG SLOCA RHR COLD LEG INJECIION B lnitiator Flag SLOCA RHR COLD LEG INJECIION A lnitiator Flag SLOCA SI HOT LEG B INITIATOR FLAG SLOCA SI HOT LEG A INITIATOR FIAG SLOCA Sl COLD LEG INJECIION lnitiator Flag SLOCA RHR PUMP SEAL INITIATOR FLAG SLOCA SI PUMP SEAL A lnitiator FIag SLOCA Sl PUMP SEAL B lnitiator Flag of 120V AC Vita! lnstrument Board I of 120V AC Vital lnstrument Board ll of 120V AC Vital Instrument Board lll 1FLCCS757AL3 lFLTBSPRAYI-B-C lFLTBSPRAY2A lFLTBSPRAYzB lFLTBSPRAYS lIMSIV lISL-IERWSTRHR lISL-IEXL7 lISL-IEX2OB ltsL-rEx32 lISL-SIPMPSEALA lISL-SIPMPSEALB
%1LDCAC lLDDAC of 120V AC Vital lnstrument Board lV
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%LLLOCA-CL1
%LLLOCA-CL2 Table I - lnitiating FTA IDENTIFIER ESCRIPTION CA ON COLD LEG 1 LLOCA ON COLD LEG 2 LLOCA ON COLD LEG 3 lLLOCA-CL4 LLOCA ON COLD LEG 4 Loss of Condenser Vacuum Loss of Primary Flow ss of Battery Board 1 of Battery Boa rd 2
%LMLOCA-CL1 LOCA ON COLD LEG 1
%LMLOCA-CL2 LOCA ON COLD LEG 2 MLOCA ON COLD LEG 3 MLOCA ON COLD LEG 4 nadvertent Closure of 1 MSIV team Generator PORV Fails Open artial Loss of ERCW UNIT 1 Partial Loss of Main Feedwater eactor Trip 1SGTRSGl RUPTURED STEAM GENERATOR IS SGl lSGTRSG2 RUPTURED STEAM GENERATOR IS SGz lSGTRSG3 RUPTURED STEAM GENERATOR IS SG3 RUPTURED STEAM GENERATOR IS SG4 lSLOCA-CLI LOCA ON COLD LEG 1 1SLOCA-CL2 LOCA ON COLD LEG 2 LOCA ON COLD LEG 3 LOCA ON COLD LEG 4 mall LOCA Stuck Open Safety Relief Valve lSLOCAV RY SMALL LOCA INITIATING EVENT 1 !S THE FAULTED SG 2 IS THE FAULTED SG 3 IS THE FAULTED SG IS THE FAULTED SG lMLOCA-CL3 lMLOCA-CL4 lPLERCW
%IPLMFW
%lSLOCA-CL4
%1SSBO-1 ECONDARY BREAK OUTSIDE CONTAINMENT SG 1
%1SSBO-2 CONDARY BREAK OUTSIDE CONTAINMENT SG 2
%1SSBO-3 CONDARY BREAK OUTSIDE CONTAINMENT SG 3
%1SSBO-4 CONDARY BREAK OUTSIDE CONTAINMENT SG 4 1TLMFW 1TTIE otal Loss of Main Feedwater urbine Trip
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Table I - lnitiatingEvente ESCRIPTIOH otal Loss of Component Cooling System Unit 2 2CCS2A oss of Component Cooling System Train 2A Power Excursion CESSTVE LOCA (VESSEL RUPTURE)
EXMFW cessive Main Feedwater Flood event induced by CCS line break (Train B)
%2FLCCS2AB592A25 Flood event induced by ccs line break in room 692.0-A15 FLCCS713A29 ood: unisolated break in CCS line in room 7L3.0-A2g FLCCS737A9 ood: CCS line break in room 737.O-A9 event induced by cCS line break in room 757,0-A13 (Surge nk B).
HELB scenario induced by MSS supply to AFW line break. Unit 2 ntribution to reactor trip initiating event frequency due to pipe
%2FLRTIE reaks - Uni
%zFfiBSPRAYI.A-B ray event on Unit 2 5.9kV boards A and B ray event on Unit 2 6.9kV boards B and C ray event on Unit 2 6.9kV boards C and D ray event on U2 board 2038 (480V TB) nadvertent Closure of all MSIVs nadvertent Safety lnjection ISLOCA RWST PIPING INITIATOR FLAG ISLOCA RHR Supply Line lnitiator Flag ISL - LETDOWN LINE INITIATOR FLAG ISL-tEX17 SLOCA RHR HOT LEG INITIATOR FLAG
!SL-IEX2OA SLOCA RHR COLD LEG INJECTION B lnitiator Flag SLOCA RHR COLD LEG lNJEgflON A lnitiator Flag rsL-tEx21 ISLOCA SI HOT LEG B INITIATOR FLAG tsL-tEx32 ISLOCA SI HOT LEG A INITIATOR FLAG ISLOCA Sl COLD LEG INJECI1ON lnitiator Flag ISLOCA RHR PUMP SEAL INITIATOR FLAG
%2ISL-SIPM PSEALA ISLOCA Sl PUMP SEAL A Initiator Flag ISLOCA Sl PUMP SEAL B lnitiator FIag of 120V AC Vital lnstrument Board I LDBAC of 120V AC Vital lnstrument Board ll 2LDCAC ss of 120V AC Vital lnstrument Board lll 2LDDAC of 120V AC Vita! Instrument Board lV LLOCA.CLl LLOCA ON COLD LEG 1 FLCCS757A13 2FLHELBAFW FLTBSPRAYI-B-C FLTBSPRAYl-C-D 2FLTBSPRAY2B 2rMStV 2ISL-IERWSTRHR tsL-tEx107 ISL-IEX15 tsL-tEx20B 2ISL-IEX33 ISL-RHRPMPSEAL
%2ISL-SIPM PSEALB LLOCA.CLz LLOCA ON COLD LEG 2
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Table{ -tnitiefffigEu#
CAFTA IDENTIFIER ESCRIPJION
))
%aLLOCA-CL3 LLOCA ON COLD LEG 3
%2LLOCA-CL4 LOCA ON COLD LEG 4
%zLOc).t of Condenser Vacuum 2LRCP 2LVB83 Loss of Primary Flow Loss of Battery Board 3 Loss of Battery Board 4 MLOCA-CLI MLOCA ON COLD LEG 1 MLOCA-CL2 MLOCA ON COLD LEG 2 MLOCA.CL3 LOCA ON COLD LEG 3 MLOCA-CL4 LOCA ON COLD LEG 4 Inadvertent Closure of 1 MSIV team Generator PORV Fails Open Partial Loss of ERCW UNIT 1 Partial Loss of Main Feedwater Reactor Trip UPTURED STEAM GENERATOR IS SG1 SGTRSG2 UPTURED STEAM GENERATOR IS SG2 SGTRSG3 UPTURED STEAM GENERATOR IS SG3 UPTURED STEAM GENERATOR IS SG4 25LOCA-CLI LOCA ON COLD LEG 1 LOCA ON COLD LEG 2 LOCA ON COLD LEG 3 LOCA ON COLD LEG 4 all LOCA Stuck Open Safety Relief Valve ERY SMALL LOCA INITIATING EVENT 1 E THE FAULTED SG IS THE FAULTED SG IS THE FAULTED SG IS THE FAULTED SG ECONDARY BREAK OUTSIDE CONTAINMENT SG 1 ECONDARY BREAK OUTSIDE CONTAINMENT SG 2 ECONDARY BREAK OUTSIDE CONTAINMENT SG 3
%2SSBO-4 ECONDARY BREAK OUTSIDE CONTAINMENT SG 4 otal Loss of Main Feedwater urbine Trip 2SSBO-1 2SSBO-2
References:
CAFTA R1 Database, lE Notebook
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Initiator T'UBN4 LER Events Reactor Trip (RTIE)
LER 390-2004-02 1
LER 390-2004-01 1
LER 390-2008-002 1
LER 390-2010-03 1
Tota!
4 Turbine Trip (TTIE)
LER 390-2006-04 1
LER 390-2006-05 1
LER 390-2003-03 1
LER 390-2003-01 1
LER 390-2008-004 1
LER 390-2010-01 1
Total 6
Total Loss of Main Feedwater (TLMFW)
LER 390-2010-02 1
Total 1
Tota! of all IEs 11 Exposure Time 7.5 year Reference 33, Table 5-3
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lnitiator Designator lnitiator Description Variable Name Prtor Posterior Mean Frequency Distribution Error Factor Mean Frequency Distribution Error Factor
%OLOSP.GR Loss of Offsite Power (Grid Related)
LOSP-GR 1.01E-02
%OLOSP-PC Loss of Offsite Power (Plant Centered)
LOSP-PC 8.12E-03
%oLosP-wr Loss of Offsite Power (Weather lnduced)
LOSP-WI 2.03E-03
%OTLERCW Total Loss of ERCW 6.78E-06
%OTLPCA Total Loss of Plant Compressed Air TLPCA 9.81E-03 Lognormal 8.4
%1CCS Total Loss of Component Cooling System Unit 1 2.49E-04
%1CCS1A Loss of Component Cooling System Train 1A 7.99E-03 oIfLCPEX Core Power Excursion CPEX 3.29E-03 Lognormal L.4
%LEX EXCESSTVE LOCA (VESSEL RUPTURE}
3.22E-O8 Lognormal 10
%IEXMFW Excessive Main Feedwater EXMFW 2.96E-02 Lognormal L.4 2.93E-O2 Lognormal L.4 OrtUMSIV lnadvertent Closure of all MSIVs
!MSIV 1.53E-02 Lognormal 1.3
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Table 3 - Initiating Event Prior and Posterior Distributions Initiator Designator lnitiator Description Variable Name Prior Posterior Mean Frequency Distribution Error Factor Mean Frequency Distribution Error Factor
%1IS!
I nadvertent Safety I njection tsr 1.55E-03 Lognormal L,4
%LtsL-IERWSTRHR ISLOCA RWST PIPING INITIATOR FLAG 1.56E-08
%1ISL-IEX1O7 ISLOCA RHR Supply Line lnitiator Flag 1.38E-07
%1tsL-tEx15 ISL - LETDOWN LINE INITIATOR FLAG 4.37E-LA
%LtsL-rEx17 ISLOCA RHR HOT LEG INITIATOR FLAG 1.78E-10
%1ISL-IEX2OA ISLOCA RHR COLD LEG INJECTION B lnitiator FIag L.74E-08
%1rsL-rEx20B ISLOCA RHR COLD LEG INJECIION A lnitiator Flag L.74E-08
%1rsL-rEx21 ISLOCA SI HOT LEG B INITIATOR FLAG 2,L2E-L2
%1tsL-tEx32 ISLOCA SI HOT LEG A INITIATOR FLAG 2,L2E-L2
%1rsL-rEx33 ISLOCA SI COLD LEG INJECTION lnitiator FIag 3.03E-09
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Table 3 - lnitiating Event Prior and Initiator Designator lnitiator Description Variable Name Prior Posterior Mean Frequency Distribution Error Factor Mean Frequency Distribution Error Factor
%1tsL-RHRPMPSEAL ISLOCA RHR PUMP SEAL INITIATOR FLAG 9.19E-05 o/oLISL-SIPMPSEALA ISLOCA SI PUMP SEAL A lnitiator Flag 1.30E-08
%1ISL-SIPMPSEALB ISLOCA SI PUMP SEAL B lnitiator Flag 1.30E-09
%1LDAAC Loss of 120V AC Vital lnstrument Board I 4.89E-03
%lLDBAC Loss of L}OV AC Vital lnstrument Board ll 4.89E-03
%lLDCAC Loss of L2OV AC Vital lnstrument Board lll 4.89E-03
%lLDDAC Loss of 120V AC Vital lnstrument Board lV 4.89E-03
%LLLOCA-CL1 LLOCA ON COLD LEG 1 LLOCA/4 3.28E-07 Lognormal LO.7
%LLLOCA-CL2 LLOCA ON COLD LEG 2 LLOCA/4 3.28E-O7 Lognormal LO.7
%LLLOCA-CL3 LLOCA ON COLD LEG 3 LLOCA/4 3.28E-07 Lognormal LO.7
%LLLOCA-CL4 LLOCA ON COLD LEG 4 LLOCA/4 3.28E-O7 Lognormal LO.7
%LLOCY Loss of Condenser Vacuum LOCV 5.58E-02 Lognormal 1,.3 5.50E-02 Lognormal 1.3
%1LRCP Loss of Primary Flow LRCP 3.62E-02 Lognormal L.4 3.58E-02 Lognormal L.4
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lnitiator Designator lnitiator Description Variable Name Prior Posterior Mean Frequensy Distribution Error Factor Mean Frequency Distribution Error Factor
%1LVBB1.
Loss of Battery Board 1 4.36E-03
%oLLVBBZ Loss of Battery Boa rd 2 4.36E-03 OALMLOCA-CL1 MLOCA ON COLD LEG 1 MLOCA/4 3.55E-06 Lognormal 10
%LMLOCA.CLz MLOCA ON COLD LEG 2 MLOCA/4 3.55E-05 Lognormal 10
%LMLOCA-CL3 MLOCA ON COLD LEG 3 MLOCA/4 3.55E-06 Lognormal 10 OrtLMLOCA-CL4 MLOCA ON COLD LEG 4 MLOCA/4 3.55E-05 Lognormal 10
%1MSIV lnadvertent Closure of 1 MSIV MSIV 1.32E-01 Lognormal L.4
%1MsVO Steam Generator PORV Fails Open MSVO 1.65E-03 Lognormal L.4
%LPLERCW Partial Loss of ERCW UNIT 1 3.28E-03
%LPLMFW Partial Loss of Main Feedwater PLMFW 1.35E-01 Lognormal L,4 1.29E-0L Lognormal L,4
%1RTIE Reactor Trip RTIE 3.20E-01 Lognormal L.4 3.27E-OL Lognormal 1.38
%ISGTRSG1 RUPTURED STEAM GENERATOR IS SG1 sGTR/4 8.85E-04 Lognormal 8.4
%lSGTRSG2 RUPTURED STEAM GENERATOR IS SG2 sGTR/4 8.85E-04 Lognormal 8.4
%1SGTRSG3 RUPTURED STEAM GENERATOR IS SG3 sGTR/4 8.85E-04 Lognormal 8,4
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Table 3 - lnitiating Event Prior and Posterior Distrirbutions lnitiator Designator lnitiator Description Variabh Name Posterior Mean Frequency Distribution Errur Factor Mean Frequency Distribution Error Factor
%1SGTRSG4 RUPTURED STEAM GENERATOR IS SG4 sGTR/4 8.85E-04 Lognormal 8,4
%lSLOCA-CLI SLOCA ON COLD LEG 1 sLocANl4 L.29E-O4 Lognormal 8.4
%lSLOCA-CL2 SLOCA ON COLD LEG 2 sLocAN/4 L.29E-O4 Lognormal 8.4
%ISLOCA-CL3 SLOCA ON COLD LEG 3 sLocANl4 L.29E-O4 Lognormal 8,4
%ISLOCA-CL4 SLOCA ON COLD LEG 4 slocAN/4 L.29E-44 Lognormal 8.4
%1SLOCAL Small LOCA Stuck Open Safety Relief Valve SLOCAL 2.88E-03 Lognormal 8.4
%1SLOCAV VERY SMALL LOCA INITIATING EVENT SLOCAV 3.82E-03 Lognormal 8.4
%1SSBr-1 SG1 IS THE FAULTED SG sLBrc/4 2.50E-04 Lognormal 3L.62
%1SSBr-2 SG2 IS THE FAULTED SG sLBrc/4 2.50E-04 Lognormal 3L.62
%1SSBr-3 SG3 IS THE FAULTED SG sLBrc/4 2.50E-04 Lognormal 3L.62
%1SSBr-4 SG4 IS THE FAULTED SG sLBrc/4 2.50E-04 Lognormal 3r.62
%1SSBO-1 SECON DARY BREAK OUTSI DE CONTAINMENT SG 1 SLBOC/4 2.50E-03 Lognormal 1.84
%1SSBO-2 SECON DARY BREAK OUTSI DE CONTAINMENT SG 2 sLBOC/4 2.50E-03 Lognormal L.84
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Table 3 - lnitlating Ev t"Flldr and Posterior Distributions lnitiator Designator lnitiator Description Variable Name Prior Posterior Mean Frequency Distribution Error Factor Mean Frequency Distributidn Error Factor
%1SSBO-3 SECON DARY BREAK OUTSI DE CONTAINMENT SG 3 sLBOC/4 2.50E-03 Lognormal L.84
%1SSBO-4 SECON DARY BREAK OUTSI DE CONTAINMENT SG 4 sLBOC/4 2.50E-03 Lognormal L.84
%ITLMFW Total Loss of Main Feedwater TLMFW 9.59E-02 Lognormal 3.5 1.10E-01 Lognormal 2.74 OALTTIE Turbine Trip TTIE 2.O4E-OL Lognormal L.4 2.4LE-OL Lognormal 1.35 o/oZCCS Total Loss of Component Cooling System Unit 2 2.49E-O4
%2CCS2A Loss of Component Cooling System Train 2A 7.65E-03
%zCPEX Core Power Excursion CPEX 3.29E-03 Lognormal L.4 ortzEK EXCESSTVE LOCA (VESSEL RUPTURE)
EX 3.22E-08 Lognormal 10
%ZEXMFW Excessive Main Feedwater EXMFW 2.96E-O2 Lognormal L.4 2.93E-02 Lognorrnal L.4
%zIMSIV lnadvertent Closure of all MSIVs IMSIV 1.53E-02 Lognorma!
1.3
%ztst I nadvertent Safety I njection ISI 1.65E-03 Lognormal L.4 ortzsL-IERWSTRHR ISLOCA RWST PIPING INITIATOR FLAG 1.55E-08
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Table 3 - lnitiating Event Prior and Posterior Distributions Initiator Designator lnitiator Description Variable Name Prior Posterior Mean Frequency Distribution Error Factor Mean Frequency Distribution Error Factor
%ztsL{Ex107 ISLOCA RHR Supply Line Initiator Flag 1.38E-07 o/ozlsL-lEX15 ISL - LETDOWN LINE INITIATOR FLAG 4.37E-L0 o/62lsL-lEXt7 ISLOCA RHR HOT LEG INITIATOR FIAG 1.78E-10
%ztsL-rEx20A ISLOCA RHR COLD LEG INJECTION B lnitiator Flag L.74E-O8 ot62lsL-lEX20B ISLOCA RHR COLD LEG INJECTION A lnitiator Flag 1.74E-08 ortasL-!Ex21 ISLOCA SI HOT LEG B INITIATOR FLAG 2.r2E-L2 o/62lsL-lEX32 ISLOCA SI HOT LEG A INITIATOR FLAG 2.L2E-L2 o/oZlSL-lEX33 ISLOCA SI COLD LEG INJECIION lnitiator FIag 3.03E-09 o6ztsL-RHRPMPSEAL ISLOCA RHR PUMP SEAL INITIATOR FLAG 9.19E-05 o6ztsL-SIPMPSEALA ISLOCA SI PUMP SEAL A lnitiator Flag 1.30E-08
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Table 3 - lnitiating Event Prior and Posterior Distributions lnitiator Designator lnitiator Description Variable Name Priui Posterior Mean Frequenf,y Distiibution Error Factor Mean Frequency Distributisn Error Factor
%ztsL-SIPM PSEALB ISLOCA S! PUMP SEAL B lnitiator Flag 1.30E-08 o/62LDAAC Loss of LZOV AC Vital lnstrument Board I 4.89E-03
%ZLDBAC Loss of L20V AC Vital Instrument Board ll 4.89E-03
%zLDCAC Loss of 120V AC Vital lnstrument Board lll 4.89E-03
%ZLDDAC Loss of L20V AC Vital lnstrument Board lV 4.89E-03
%ZLLOCA-CL1 LLOCA ON COLD LEG 1 LLOCA/4 3.28E-07 Lognormal LO.7
%aLLOCA-CL2 LLOCA ON COLD LEG 2 LLOCA/4 3.28E-O7 Lognormal LO.7
%ZLLOCA-CL3 LLOCA ON COLD LEG 3 LLOCA/4 3.28E-O7 Lognormal LO.7 o/62LLOCA-CL4 LLOCA ON COLD LEG 4 LLOCA/4 3.28E-O7 Lognormal LO.7 YoZLOO'l Loss of Condenser Vacuum LOCV 6.58E-02 Lognormal 1.3 5.50E-02 Lognormal 1.3 O6ZLRCP Loss of Primary Flow LRCP 3.62E-O2 Lognormal L.4 3.58E-02 Lognormal L.4
%zLVBB3 Loss of Battery Board 3 4.35E-03 OAaINBB4 Loss of Battery Board 4 4.36E-03 o/oZMLOCA-CL1 MLOCA ON COLD LEG 1 MLOCA/4 3.55E-05 Lognormal 10
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Distributions Table 3 - lnitiating Event Prior and Posterior Distribul lnitiator Designator lnitiator Description Variable Name Posterior Mean Frequency Distribution Error Factor Mean Frequency Distribution Eror Factor o/IZMLOCA-CLz MLOCA ON COLD LEG 2 MLOCA/4 3.55E-05 Lognormal 10 o/oZMLOCA-CL3 MLOCA ON COLD LEG 3 MLOCA/4 3.55E-06 Lognormal 10 o/62MLOCA-CL4 MLOCA ON COLD LEG 4 MLOCA/4 3.55E-06 Lognormal 10
%2MSrV lnadvertent Closure of 1 MSIV MSIV 1.32E-01 Lognormal L.4 o/62MSVO Steam Generator PORV Fails Open MSVO 1,55E-03 Lognormal L.4
%2PLERCW Partial Loss of ERCW UNIT 1 3.26E-03
%2PLMFW Partial Loss of Main Feedwater PLMFW 1.35E-01 Lognormal L.4 1.29E-01 Lognormal L.4
%aRTIE Reactor Trip RTIE 3.20E-01 Lognormal L.4 3.27E-OL Lognormal 1.38
%ZSGTRSG1 RUPTURED STEAM GENERATOR IS SG1 sGTR/4 8.85E-04 Lognormal 8.4 OAZSGTRSG2 RUPTURED STEAM GENERATOR IS SG2 scrR/4 8.85E-04 Lognormal 8,4 o/IZSGTRSG3 RUPTURED STEAM GENERATOR IS SG3 sGTR/4 8.85E-04 Lognormal 8.4 o/IZSGTRSG4 RUPTURED STEAM GENERATOR IS SG4 sGTR/4 8.85E-04 Lognormal 8.4 o,AZSLOCA-CL1 SLOCA ON COLD LEG 1 sLocAN/4 L.29E-O4 Lognormal 8.4
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lnitiator Designator lnitiator Description Variable Name Posterior Mean Frequency Error Factor Mean Frequency Distrihutlon Error Factor oAZSLOCA-CL2 SLOCA ON COLD LEG 2 sLocAN/4 L.29E-O4 Lognormal 8.4 o/oZSLOCA-CL3 SLOCA ON COLD LEG 3 sLocAN/4 L.29E-O4 Lognormal 8.4
%ZSLOCA-CL4 SLOCA ON COLD LEG 4 sLocAN/4 L.29E-O4 Lognormal 8.4 oI62SLOCAL Small LOCA Stuck Open Safety Relief Valve SLOCAL 2.88E-03 Lognorma!
8.4 o/IZSLOCAV VERY SMALL LOCA INITIATING EVENT SLOCAV 3.82E-03 Lognormal 8.4
%2SSBr-1 SG1 IS THE FAULTED SG sLBtc/4 2.50E-04 Lognormal 3L.62
%2SSBr-2 SG2 IS THE FAULTED SG sLBtc/4 2.50E-04 Lognormal 3L.62
%2SSBr-3 SG3 IS THE FAULTED SG sLBrc/4 2.50E-04 Lognormal 3L.62
%2SSBr-4 SG4 IS THE FAULTED SG sLBtc/4 2.50E-04 Lognormal 3L.62
%2SSBO-1 SECON DARY BREAK OUTSI DE CONTAINMENT SG 1 SLBOC/4 2.50E-03 Lognormal L.84
%2SSBO-2 SECON DARY BREAK OUTSI DE CONTAINMENT SG 2 sLBOC/4 2.50E-03 Lognormal 1.84
%2SSBO-3 SECON DARY BREAK OUTSI DE CONTAINMENT SG 3 sLBOC/4 2.50E-03 Lognormal L.84
%2SSBO-4 SECONDARY BREAK OUTSI DE CONTAINMENT SG 4 sLBOC/4 2.50E-03 Lognormal 1.84
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Initiator Designator Initiator Description Variable Name Prior Posterior Mean Frequency Distribution Error Factor Mean Frequency Distribution Error Factor OA2TLMFW Total Loss of Main Feedwater TLMFW 9.59E-02 Lognormal 3.6 1.10E-01 Lognormal 2.74 o/oZTTlE Turbine Trip TTIE 2.04E-OL Lognormal L,4 2.4LE-OL Lognormal 1.35 Reference CAFTA model, Reference 33 Table 5-2 and Section 6, Reference 42Table 8-2.
Calculation No. MDN-000-999-2008-01 51 Rev: 001 Plant: WBN Unit 0 Page: 51
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lnitiating Event CCSTL Tota! Loss of CCS 2.49E-04 2.49E-04 Oo/o ISLOCAs, total 9.41E-05 9.41E-05 Oo/o Flooding, total 2.26E-O2 2.26E-02 Oo/o SLBIC Steam Line Break lnside Containment 1.00E-03 1.00E-03 o%
ERCW1B Partial Loss of ERCW 3.28E-03 3.28E-03 0%
ERCW2A Partial Loss of ERCW 3.25E-03 3.25E-03 o%
SLBOC Steam Line Break Outside Containment 1.00E-02 1.00E-02 o%
CCSA Loss of CCS Train 1A 7.99E-03 7.99E-03 o%
LVBBx Loss of Battery Board x 4.35E-03 4.35E-03 o%
SLOCAN Small LOCA Non-lsolable 5.20E-04 5.14E-04
-LOA IMSIV lnadvertent Closure of all MSIVs 1.53E-Oz 1.53E-02 o%
TLMFW Total Loss of Main Feedwater 7.OLE-Oa 1.10E-01 57%
EXMFW Excessive Main Feedwater 3.95E-02 2.93E-02
-2604 SLOCAV Very Small LOCA Non-lsolable 3.88E-03 3.92E-03
-204 ISI I nadvertent Safety I njection 1.03E-02 1.55E-03
-9404 RTIE Reactor Trip 2.85E-01 3.40E-01 L9%
SGTR Steam Generator Tube Rupture 3.54E-03 3.54E-03 o%
MLOCA Medium Break LOCA 1.44E-05 1.42E-05
-LOA LLOCA Large Break LOCA 1.33E-06 1.31E-06
-2%
LRCP Loss of 1 or More RCs/Primary FIow 2.89E-02 3.58E-02 24Yo PLMFW Partial Loss of Main Feedwater 1.46E-01 1.29E-01
-L2%
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mftiefin*
Event Description LOCV Loss of Condenser Vacuum 5.53E-02 5.50E-02 o%
LOSP-xx Loss of Offsite Power, total 2.03E-02 2.03E-02 o%
MSIV lnadvertent Closure of One MSIV L.97E-02 L.32E-02
-33%
CPEX Core Power Excursion 7.27E-O3 3.29E-03
-55o/o ELOCA Excessive LOCA 1.00E-07 3.22E-09
-68%
MSVO Steam Generator PORV Fails Open 8.55E-04 1.55E-03 93%
TTIE Turbine Trip 2.32E-OL 2.4LE-OL 4%
U1 LDXAC Loss of 120V AC Vital Board x 4.89E-03 4.89E-03 o%
ERCWTL Total Loss of ERCW 6.78E-06 6.78E-06 o%
SLOCAL Stuck Open Safety/Relief Valve 2.98E-03 2.88E-03 o%
TLPCA Total Loss of Plant Compressed Air 9.81E-03 9.81E-03 o%
Reference 33, Table 8-1, Table 9-1 Reference 41, Table 7-1 Reference 42,Table 8-2 CAFTA Flooding lE Frequency from model Revision 4 values from R4 lE Notebook
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PDS NHD Containment is not bypassed. There is no or small leakage from the RCS and it is at a high pressure at the time of core damage. There is no feedwater or auxiliary feedwater to the steam generators and the steam generators are dry at the time of core damage.
NLD Containment is not bypassed. There is a medium or large LOCA from the RCS and it is at low or atmospheric pressure at the time of core damage.
There is no feedwater or auxiliary feedwater to the steam generators and the steam generators are dry at the time of core damage.
NHW Containment is not bypassed. There is no or small leakage from the RCS and it is at a high pressure at the time of core damage. Feedwater or auxiliary feedwater is being supplied to the steam generators and the steam generator water level is at nominal level at the time of core damage.
NLW Containment is not bypassed. There is a medium or large LOCA from the RCS and it is at low pressure at the time of core damage. Feedwater or auxiliary feedwater is being supplied to the steam generators and the steam generator water level is at nominal level at the time of core damage.
BHD The containment is bypassed at the time of core damage (i.e., Steam Generator Tube Rupture (SGTR) or ISLOCA). There is no or small leakage from the RCS and it is at high or intermediate pressure (above the accumulator setpoint) at the time of core damage. There is no feedwater or auxiliary feedwater to the steam generators and the steam generators are dry at the time of core damage.
BLD The containment is bypassed at the time of core damage (i.e., SGTR or ISLOCA). There is a large leakage from the RCS or the RCS has been depressurized and it is at a low pressure at the time of core damage. There is no feedwater or auxiliary feedwater to the steam generators and the steam generators are dry at the time of core damage.
BHW The containment is bypassed at the time of core damage (i.e., SGTR or ISLOCA). There is no or small leakage from the RCS and it is at high/intermediate pressure at the time of core damage. Feedwater or auxiliary feedwater is being supplied to the steam generators and the steam generators are at nominal level at the time of core damaqe.
BLW The containment is bypassed at the time of core damage (i.e., SGTR or ISLOCA). There is large leakage from the RCS or the RCS has been depressurized and it is at a low pressure at the time of core damage.
Feedwater or auxiliary feedwater is being supplied to the steam generators and the steam generators are at nominal level at the time of core damaqe.
Reference 34, T able 6.3-1
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Group Gategory lnitiator Designator Loss of Coolant
- 1. Excessive LOCA (reactor vessel failure) o/o1EX NONE
- 2. Large LOCA (> 6-inch diameter) o/o1LLOCA-cL1,2,3,4 LLOCA
- 3. Medium LOCA (>2 to < 6-inch diameter)
%lMLOCA-cl1,2,3,4 MLOCA
- 4. Small LOCA (non-isolable)
%lSLOCA-cl1,2,3,4 SLOCA
- 5. Small LOCA (isolable)
%lSLOCAL SLOCA
- 6. Verv Small LOCA (non-isolable)
%lSLOCAV SLOCAV
- 7. Steam Generator Tube Rupture
%1SGTRSG1
,2,3,4 SGTR
- 8. Interfacing Systems LOCA - Large and Medium
%1rsl-IERWSTRHR,
%1lSL-lEXxxx ISLOCA
- 9. Interfacing Systems LOCA - Small
%1!SL-xxxPMPSEAL ISLOCA Transients
- 10. Reactor Trips
%1RTIE GTRAN
- 11. Core Power Excursion o/olCPEX GTRAN
- 12. Turbine Trip o/olTTlE GTRAN
- 13. lnadvertent Safetv lniection
%1rsr GTRAN
- 14. Total Loss of All Main Feedwater
%lTLMFW GTRAN
- 15. Partial Loss of Main Feedwater o/oIPLMFW GTRAN
- 16. Loss of Condenser Vacuum o/olLOCV GTRAN
- 17. Excessive Feedwater o/oIEXMFW GTRAN
- 18. lnadvertent Closure of One MSIV
%1MSIV GTRAN
- 19. lnadvertent Closure of All MSIVs o/ollMSlV GTRAN
- 24. Loss of Primary Flow
%1LRCP GTRAN 21. Steam Line Break Outside Containment
%1SSBO-1,
2,3,4 SSBO
- 22. Steam Line Break Inside Containment
%1SSBI-1,2,3,4 SSBI
- 23. lnadvertent Opening of Main Steam Relief Valves
%1MSVO SSBO
- 24. lnadvertent Safety Iniection
%1ISI GTRAN Loss of Support
!nitiating Events
%OLOSP-GR, PC, WI GTRAN
- 26. Loss of 1-l Vital AC lnstrument Board o/o1LD,AAC, GTRAN
- 27. Loss of 1-ll Vital AC lnstrument Board o/oILDBAC GTRAN
- 28. Loss of 1-lll Vital AC Instrument Board o/oILDCAC GTRAN
- 29. Loss of 1-lV Vital AC lnstrument Board o/oILDDAC GTRAN
- 30. Loss of Vital Batterv Board I o/o1LVBB1 GTRAN
- 31. Loss of Vita! Battery Board ll
%1LVBB2 GTRAN
- 32. Total Loss of CCS
%1CCS GTRAN
- 33. Loss of CCS Train A o/o1CCS1A GTRAN
- 34. Total Loss of ERCW
%OTERCW GTRAN
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Group Category
- 35. Loss of ERCW to Unit 1 o/o1PLERCW GTRAN
- 36. Total Loss of Plant Compressed Air
%OTLPCA GTRAN Reference 34, Table 6. 1 -1
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Table 7 -- Suceess Griteria for LLOCA Path Name ACG LPIS LPH LLOCA-oo1 3 of 3 to intact legs 1 of 2 RHR pumps to 3 of 3 intact legs 1of 2 RHR pumps to 1 of 2 intact legs 1 ot 2 RHR pumps to 2 of 4 Iegs and 1 of 2 SI pumps to 2 of 4 legs Reference 35, Table 7.2-1
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Table I -- Success Griteria for IUILOCA Path Name CVCS SI HPR AFW LPI Mission Time MLOCA-o01 1 of 2 CVCS pumps to 3 of 3 intact legs N/A 1 of 2 CVCS pumps to 3 of 3 intact Iegs supported by 1 ot 2 RHR pumps taking suction from the sump N/A N/A N/A N/A MLOCA-OO2 1 of 2 CVCS pumps to 3 of 3 intact legs N/A FAILED 1ot2 MDAFW pumps or 1 of 1 TD AFW pump tolSG Open 1 SG PORV or 1 bank of steam dumps within 15 minutes of HPR failure N/A 1of 2 RHR pumps to 1 of 2 Iegs MLOCA-OO6 FAILED 1 of 2 Safety Injection pumps to3of3intact legs 1 of 2 SI pumps to3of3intact legs supported by 1 of 2 RHR pumps taking suction from the sump N/A N/A N/A N/A
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Path Name CVCS SI HPR AFW AFVTIl LPI LPR Mission Time
< I hour'
< t hour'
> 23 hours2.662037e-4 days <br />0.00639 hours <br />3.80291e-5 weeks <br />8.7515e-6 months <br />' N/A I hour' 23 hours2.662037e-4 days <br />0.00639 hours <br />3.80291e-5 weeks <br />8.7515e-6 months <br /> 6-16 hours 6-18 hours" 8-18 hours*
7-19 hours' 5-17 hours' MLOCA-OO7 FA!LED 1 of 2 Safety lnjection pumps to3of3intact legs FAILED 1of 2 MDAFW pumps or 1 of 1 TD AFW pump tolSG Open 1 SG PORV or 1 bank of steam dumps within 15 minutes of HPR failure N/A 1of 2 RHR pumps to 1 of 2 Iegs MLOCA-o11 FAILED FAILED N/A 1ot2 MDAFW pumps or 1 of 1 TD AFW pump tolSG Open 1 SG PORV or 1 bank of steam dumps within 15 minutes of initiator 1of 2 RHR pumps to 3 of 3 intact legs 1of 2 RHR pumps to 1 of 2 legs Note 1: Times g Note 2: Times g ven are with containment spray in operation.
ven are without containment spray in operation.
Reference 35, Table 7.3-1
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Path Name CVCS sr.
ATW
.HPR LPR LT.HR Mission Time
< t hourl
< t hourr
'13 houre N/A
<1 hourl
>23 hoursl 11 hours1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br /> 24 hours 15 hour1.736111e-4 days <br />0.00417 hours <br />2.480159e-5 weeks <br />5.7075e-6 months <br />sz 14 hours1.62037e-4 days <br />0.00389 hours <br />2.314815e-5 weeks <br />5.327e-6 months <br />s 5
hourtz 19 hour2.199074e-4 days <br />0.00528 hours <br />3.141534e-5 weeks <br />7.2295e-6 months <br />sz SLOCA.OOl 1of 2 CVCS pumps to 3of3 intact legs N/A 1 of 2 MD AFW pumps or 1 of 1 TD AFW pump to 'l SG N/A N/A 1of 2 CVCS pumps to 3 of 3 intact legs supported by 1 of2 RHR pumps taking suction from the sump N/A N/A N/A CST refill N/A SLOCA-OO3 1of 2 CVCS pumps to 3of3 intact legs N/A 1 of 2 MD AFW pumps or 1 of 1 TD AFW pump to 1 SG N/A N/A FAILED Open 1 SG PORV or 1 bank of steam dumps within 30 minutes of HPR failure N/A 1of 2 RHR pumps tolof 2 legs CST refil!
N/A sLocA-006 1ot2 CVCS pumps to 3of3 intact legs N/A 1 of 2 MD AFW pumps or 1 of 1 TD AFW pump to 1 SG N/A N/A FA!LED FAILED N/A N/A N/A Transfer Successful
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Path Name CVCS SI AFUtfz BF HPR AFVUS LPII LFR LIHR,'
MUSL Mission Time
< I hourl
'
- I hourl N/A N/A
>23, hoursr 11 hours1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br /> 15 hoursz 14 hours1.62037e-4 days <br />0.00389 hours <br />2.314815e-5 weeks <br />5.327e-6 months <br />s 5
hoursz 19 hour2.199074e-4 days <br />0.00528 hours <br />3.141534e-5 weeks <br />7.2295e-6 months <br />sz sLocA-008 1of 2 CVCS pumps to 3of3 intact legs N/A FAILED N/A 1of 2 CVCS pumps and open 1 PZR PORV within 30 minutes of 260/o SG WR 1of 2 CVCS pumps to 3of3 intact legs supported by 1 of2 RHR pumps taking suction from the sump N/A N/A N/A N/A N/A slocA-01 1 FAILED 1of 2 Safety lnjection pumps to 3of3 intact legs 1 ot 2 MD AFW pumps or 1 of 1 TD AFW pump to 1 SG N/A N/A 1 of 2 Sl pumps to 3of3 intact legs supported by 1 ot2 RHR pumps taking suction from the sump N/A N/A N/A CST refill N/A sLocA-o13 FA!LED 1of 2 Safety lnjection pumps to 3of3 intact 1 of 2 MD AFW pumps or 1 of 1 TD AFW pump to 1 SG N/A N/A FAILED Open 1 SG PORV or 1 bank of steam dumos N/A 1of 2 RHR pumps tolof 2 legs CST refill N/A
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SUMMARY
Criteiia for SLOCA Path Name CVCS SI AFW AFWz
.BF.
HPR AFtrtIS LPR LTHR MUSL Mission Time
< t hou/
< t hourt I3 houre N/A NIA
>2?
hourer 11 houls 15 hour1.736111e-4 days <br />0.00417 hours <br />2.480159e-5 weeks <br />5.7075e-6 months <br />s2 14 hurs2 5
hoursz 19 hour2.199074e-4 days <br />0.00528 hours <br />3.141534e-5 weeks <br />7.2295e-6 months <br />sz legs within 30 minutes of HPR failure SLOCA.O16 FAILED 1of 2 Safety lnjection pumps to 3of3 intact legs 1 of 2 MD AFW pumps or 1 of 1 TD AFW pump to 'l SG N/A N/A FAILED FAILED N/A N/A N/A Transfer Successfu!
sLocA-o18 FA!LED 1of 2 Safety lnjection pumps to 3of3 intact legs FAILED N/A 1ot2 Safety lnjection pumps and open 2PZR PORVs within 25 minutes of 260/o SG WR 1 of 2 Sl pumps to 3of3 intact legs supported by1ot2 RHR pumps taking suction from the sump N/A N/A N/A N/A N/A SLOCA-021 FAILED FAILED 1 of 2 MD AFW pumps or 1 of 1 TD AFW pump to 1 SG Open 1 SG PORV or 1 bank of steam dumps within 60 minutes N/A N/A N/A 1ot2 RHR pumps to3of 3 intact legs 1ot2 RHR pumps tolof 2 legs CST refill N/A
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Tahle S Path Name CVGS SI AFW AFUI'z
.BF HPR AFWS LPI LPR LTHR
..MUSL Mission Time
< I hour{
< I hourl N/A
<1 houl
> 23' hourrgl 11 hours1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br /> 15 hounsz 14 hour1.62037e-4 days <br />0.00389 hours <br />2.314815e-5 weeks <br />5.327e-6 months <br />sl 5
hoursz 19 hour2.199074e-4 days <br />0.00528 hours <br />3.141534e-5 weeks <br />7.2295e-6 months <br />sa of initiator Note 1: Times given are with containment spray in operation.
Note 2: Times given are without containment spray in operation.
Reference 35, Table 7.4-1
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Table t0 -- tiuccess Criteria for StOGAtf Path Name AFW LTHR cvcs SI BF HPR Mission Time lS lmurs I hours 3.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />' lE hours'
.NIA
&10 hours' SLOCAV-OO1 1of 2MDAFW pumps or 1 of 1 TD AFW pump to 1 SG CST refill N/A N/A N/A N/A SLOCAV-OO2 lof2MDAFW pumps or 1 of 1 TD AFW pump to 1 SG FAILED 1 of 2 CVCS pumps to 4 of 4 legs N/A 1 of 2 CVCS pumps, 1 PZR PORV within 15 minutes of 26% SG WR 1 of 2 CVCS pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump SLOCAV.OOs 1of 2MDAFW pumps or 1 of 1 TD AFW pump to 1 SG FA!LED FAILED 1 of 2 Safety
!njection pumps to 4 of 4 legs 1 of 2 Safety lnjection pumps, 2 PZR PORVs within 10 minutes of 26% SG WR 1of2Sl pumpsto4of4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump SLOCAV-OOg FAILED N/A 1 of 2 CVCS pumps to 4 of 4
!egs N/A 1 of 2 CVCS pumps, 1 PZR PORV within 15 minutes of 26% SG WR 1 of 2 CVCS pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump SLOCAV-012 FAILED N/A FAILED 1 of 2 Safety lnjection pumps to 4 ol 4 legs 1 of 2 Safety lnjection pumps, 2 PZR PORVs within 10 minutes of 260/0 SG WR 1of 2Sl pumpsto4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump Note 1: Times given are with containment spray in operation. Mission times without containment spray are not given because GTRAN is more representative of the accident scenarios without containment spray in operation.
Reference 35, Table 7.5-1
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Path Name CVCS sl AFlttl lsot_t ssr PR RSI BF HPR Mission Time
< t hour
<1 hour I hourc N/A N/A NTA r8 hure N/4,,
N/A
> 23 hours2.662037e-4 days <br />0.00639 hours <br />3.80291e-5 weeks <br />8.7515e-6 months <br /> ssBr-001 1of 2 CVCS pumps to 4 of 4 legs N/A 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation of faulted SG or 3 of 4 non-faulted SGs Within t hour of pressurizer level 32ft PORV reseats CST refill N/A NIA N/A ssBr-002 1ot2 CVCS pumps to 4 of 4 legs N/A 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation of faulted SG or 3 of 4 non-faulted SGs Within t hour of pressurizer level 32 ft PORV reseats FAILED Successful Sl system reinitiation within t hours of CST depletion 1 of 2 CVCS pumps, 1 PZR PORV within 15 minutes of 26%
SG WR 1 of 2 CVCS pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ssBt-006 1of 2 CVCS pumps to 4 of 4 legs N/A 1 of 2 MD AFW pumps orloflTD AFW pump to lSGSG Successful lsolation of faulted SG or 3 of 4 non-faulted SGs Within t hour of pressurizer level 32 ft FAILED N/A Successful Sl system reinitiation within t hours of CST depletion N/A 1 of 2 CVCS pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ssBr-009 1of 2 CVCS pumps to 4 of 4 legs N/A 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation of faulted SG or 3 of 4 non-faulted SGs FAILED N/A N/A N/A N/A 1 of 2 CVCS pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ssBt-01 1 1of 2 CVCS pumps to 4 of 4 legs N/A 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG FAILED N/A N/A CST refill N/A N/A N/A
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Table 11 -- Success Griteria for SSBI Path Name CVGS sl AF'TIV ISOLl ssl PR LTHR RSI BF HPR Mission Time
< I hour N/A NfA
.}UA Nf,A N/A
> 23 hours2.662037e-4 days <br />0.00639 hours <br />3.80291e-5 weeks <br />8.7515e-6 months <br /> ssBt-012 1of 2 CVCS pumps to 4 of 4 legs N/A 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG FAILED N/A N/A FA!LED N/A 1 of 2 CVCS pumps, l PZR PORV within 15 minutes of 260/o SG WR 1 of 2 CVCS pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ssBt-015 1of 2 CVCS pumps to 4 of 4 legs N/A FAILED FAILED N/A N/A N/A N/A 1 ot 2 CVCS pumps, 1 PZR PORV within 15 minutes of 260/o SG WR 1 of 2 CVCS pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ssBt-018 FA!LED 1 of 2 Sl pumps to 4 of 4 legs 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation of faulted SG or 3 of 4 non-faulted SGs Within t hour of pressurizer level 32 ft PORV reseats CST refill N/A N/A N/A ssBr-019 FAILED 1 of 2 Sl pumps to 4 of 4 legs 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation of faulted SG Or 3 of 4 non-faulted SGs Within t hour of pressurizer level 32 ft PORV reseats FAILED Successful Sl system reinitiation within t hours of CST depletion 1 of 2 Safety lnjection pumps, 2 PZR PORVs within 30 minutes of 26%
SG WR 1 of 2 Sl pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ssBr-023 FAILED 1 of 2 Sl pumps to 4 of 4 legs 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation of faulted SG or 3 of 4 non-faulted SGs Within t hour of pressurizer level 32 ft FAILED N/A Successful Sl system reinitiation within t hours of CST depletion N/A 1 of 2 Sl pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump
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Table {1, -; Success Criteria for SSBI Path Name GVCS SI AFW rsoLr ssr PR LTHR RSI BF HPR Mission Time
< t hour
<1 hoUr I houns N/A lrlrA MA N/A N/A
> 23 hours2.662037e-4 days <br />0.00639 hours <br />3.80291e-5 weeks <br />8.7515e-6 months <br /> ssBt-026 FAILED 1 of 2 Sl pumps to 4 of 4 legs 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation of faulted SC or 3 of 4 non-faulted SGs FAILED N/A N/A N/A N/A 1 ol 2 Sl pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ssBr-028 FAILED 1 of 2 Sl pumps to 4 of 4 legs 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG FAILED N/A N/A CST refill N/A N/A N/A ssBr-029 FAILED 1 of 2 Sl pumps to 4 of 4 legs 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG FAILED N/A N/A FAILED N/A 1 of 2 Safety lnjection pumps, 2PZR PORVs within 30 minutes of 260/o SG WR 1 of 2 S! pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ssBt-032 FAILED 1 of 2 Sl pumps to 4 of 4 legs FAILED FAILED N/A N/A N/A N/A 1 of 2 Safety lnjection pumps, 2 PZR PORVs within 30 minutes of 26%
SG WR 1 of 2 Sl pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ssBr-035 FAILED FAILED 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation of fautted SG or 3 of 4 non-faulted SGs N/A N/A GST refill N/A N/A N/A Reference 35, Table 7.6-1
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Table Path Name CVCS st AFW rsoL0
,ssl PR LTHR RSI BF HPR Mission Time 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 6 hours N/A N'A N/A tl6 houre N/A 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> ssBo-oo1 1 of 2 CVCS pumps to 4 of 4 legs N/A 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation all non-faulted SGs Within t hour of pressurizer level 32 ft PORV reseats CST refill N/A N/A N/A ssBo-002 1 of 2 CVCS pumps to 4 of 4 legs N/A 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation all non-faulted SGs Within t hour of pressurizer level 32 ft PORV reseats FAILED Successful Sl system reinitiation within t hours of CST depletion 1 of 2 CVCS pumps, 1 PZR PORV within 15 minutes of 260/o SG WR 1 of 2 CVCS pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ssB0-006 1 of 2 CVCS pumps to 4 of 4 legs N/A 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation all non-faulted SGs Within t hour of pressurizer level 32 ft FAILED N/A Successful Sl system reinitiation within t hours of CST depletion N/A 1 of 2 CVCS pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ssB0-009 1 of 2 CVCS pumps to 4 of 4 legs N/A 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation all non-faulted SGs FAILED N/A N/A N/A N/A 1 of 2 CVCS pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump
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rs Criteria for SSBO Path Name CVCS SI AFW rsoLo ssl PR LTHR RSI BF HPR Mission Time 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 6 hours I hourr NlA N/A NIA 16,hours N/A Ft/A 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> ssBo-o1 1 1 of 2 CVCS pumps to 4 of 4 legs N/A 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG FAILED N/A N/A CST refill N/A N/A N/A ssBo-o12 1 of 2 CVCS pumps to 4 of 4 legs N/A 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG FAILED N/A N/A FAILED N/A 1 of 2 CVCS pumps, 1 PZR PORV within 15 minutes of 260/o SG WR 1 of 2 CVCS pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ssBo-o15 1 of 2 CVCS pumps to 4 of 4 legs N/A FAILED FAILED N/A N/A N/A N/A 1 ot 2 CVCS pumps, 1 PZR PORV within 15 minutes of 260/0 SG WR 1 of 2 CVCS pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ssBo-o18 FAILED 1 of 2 Sl pumps to 4 of 4 legs 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation all non-faulted SGs Within t hour of pressurizer level 32 ft PORV reseats CST refill N/A N/A N/A ssBo-o19 FAILED 1 of 2 Sl pumps to 4 of 4 legs 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation all non-faulted SGs Within t hour of pressurizer level 32 ft PORV reseats FAILED Successful Sl system reinitiation within t hours of CST depletion 1 of 2 Safety lnjection pumps, 2 PZR PORVs within 30 minutes of 260/o SG WR 1 of 2 Sl pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump
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Path Narne CVCS sl AFW tso[o s8r PR LTHR RSI BF rHPR Mission Time 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 6 hours I hours N/A NIA.
NTA 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> N/A T{/A 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> ssBo-023 FAILED 1 of 2 Sl pumps to 4 of 4 legs 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation all non-faulted SGs Within t hour of pressurizer level 32 ft FAILED N/A Successful Sl system reinitiation within t hours of CST depletion N/A 1 of 2 Sl pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ss80-026 FAILED 1 of 2 Sl pumps to 4 of 4 legs 1 of 2 MD AFW pumps orl of 'l TD AFW pump to 1SG Successful lsolation all non-faulted SGs FAILED N/A N/A N/A N/A 1 of 2 Sl pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ssB0-028 FAILED 1 of 2 Sl pumps to 4 of 4 legs 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG FAILED N/A N/A CST refill N/A N/A N/A ssB0-029 FA!LED 1 of 2 Sl pumps to 4 of 4 legs 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG FAILED N/A N/A FAILED N/A 1 of 2 Safety lnjection pumps, 2 PZR PORVs within 30 minutes of 260/o SG WR 1 of 2 S! pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump ssBo-032 FAILED 1 of 2 Sl pumps to 4 of 4 legs FAILED FAILED N/A N/A N/A N/A 1 of 2 Safety lnjection pumps, 2 PZR PORVs within 30 minutes of 260/, SG WR 1 of 2 Sl pumps to4of4intact legs supported by 1 of 2 RHR pumps taking suction from the sump
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Table 12 - Success Griteria for SSBO Path Name CVGS sr AFW ISOLO SSI PR TTTIR RSt BF HPR Mission Time 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 6 hours I hours
}UA N/A NIA N/A N/A 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> ssB0-035 FAILED FAILED 1 of 2 MD AFW pumps orloflTD AFW pump to 1SG Successful lsolation all non-faulted SGs N/A N/A CST refill N/A N/A N/A Reference 35, Table 7.7-1
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Table t3 -- $uccess Griteria for GTRAN Path Name AFW LTHR CVC$
SI BF HPR Mission Tirne 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> 14 hourc
< I hour N/,A
>23 hours GTRAN-OO1 1of 2 MDAFW pumps or 1 of 1 TD AFW pump to 1 SG CST refi!!
N/A N/A N/A N/A GTRAN-O02 1of 2 MDAFW pumps or 1 of 1 TD AFW pump to 1 SG FAILED 1 of 2 CVCS pumps to 4 of 4 legs N/A 1 of 2 CVCS pumps, 1 PZR PORV within 10 minutes of 260/o SG WR 1 of 2 CVCS pumps to 4 of 4 intact Iegs supported by 1 of 2 RHR pumps taking suction from the sump GTRAN-OO5 1of 2 MDAFW pumps or 1 of 1 TD AFW pump to 1 SG FAILED FAILED 1of2SI pumps to 4 of 4legs 1 of 2 Safety lnjection pumps, 2 PZR PORVs within 10 minutes of 260/o SG WR 1 of 2 Sl pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump GTRAN-OO9 FAILED N/A 1 of 2 CVCS pumps to 4 of 4 legs N/A 1 of 2 CVCS pumps, 1 PZR PORV within 10 minutes of 260/0 SG WR 1 of 2 CVCS pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump GTRAN-o12 FAILED N/A N/A 1of2SI pumps to 4 of 4legs 1 of 2 Safety lnjection pumps,2 PZR PORVs within 10 minutes of 26%
SG WR 1 of 2 Sl pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump Reference 35, Table 7.8-1
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Table t4 -- $uccess Criteria for SGTR Path Name CVCS SI AFW SL AFWS BF ssl RT,TIST RHR REGIRC Misslon Time 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> 36 hours 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> NIA N/A N'A.'
N/A 33 hours3.819444e-4 days <br />0.00917 hours <br />5.456349e-5 weeks <br />1.25565e-5 months <br /> SGTR-OO1 1of 2 CVCS pumps to 4of4 legs N/A lof2MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG lsolate ruptured SG within 15 minutes of initiator Open 1 SG PORV or 1 bank of steam dumps within 25 minutes of initiator N/A Within t hour of pressurizer level 32 ft N/A 1of 2 RHR pumps to 2of2 intact legs N/A N/A SGTR.OO2 1of 2 CVCS pumps to 4of4 legs N/A 1of 2 MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG lsolate ruptured SG within 15 minutes of initiator Open 1 SG PORV or 1 bank of steam dumps within 25 minutes of initiator N/A Within t hour of pressurizer level 32 ft N/A FAILED N/A CST refill SGTR.OO4 1of 2 CVCS pumps to 4of4 legs N/A lof2MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG lsolate ruptured SG within 15 minutes of initiator Open 1 SG PORV or 1 bank of steam dumps within 25 minutes of initiator N/A FAILED RWST refill N/A N/A N/A SGTR.OO5 1of 2 CVCS pumps to 4of4 legs N/A lot2MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG lsolate ruptured SG within 15 minutes of initiator Open 1 SG PORV or 1 bank of steam dumps within 25 minutes of initiator N/A FAILED FAILED N/A N/A CST refill SGTR.OOT 1ot2 CVCS pumps to 4of4 legs N/A lof2MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG lsolate ruptured SG within 15 minutes of initiator FAILED N/A N/A RWST refill N/A N/A N/A
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Path Name GVCS SI AFW SL AFWS BF sst RWST RHR RECIRC LTHR Mission Time 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> 36 hours 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> N/A N/A N/A NIA 36 houns 33 hours3.819444e-4 days <br />0.00917 hours <br />5.456349e-5 weeks <br />1.25565e-5 months <br /> 24 hours SGTR.OOS 1ot2 CVCS pumps to 4ot4 legs N/A lof2MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG lsolate ruptured SG within 15 minutes of initiator FAILED N/A N/A FAILED N/A N/A CST refill SGTR-O1O 1of 2 CVCS pumps to 4of4 legs N/A lof2MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG FAILED N/A N/A N/A RWST refill N/A N/A N/A SGTR.OI 1 1of 2 CVCS pumps to 4of4 legs N/A 1of 2 MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG FAILED N/A N/A N/A FAILED N/A N/A CST refill SGTR-o13 1of 2 CVCS pumps to 4of4 legs N/A FAILED N/A N/A 1 of 2 CVCS pumps, 1 PZR PORV within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> of 260/o SG WR N/A N/A N/A 1 of 2 CVCS pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump N/A SGTR.O16 N/A 1 of 2 Sl pumps to 4of4 Iegs lof2MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG lsolate ruptured SG within 15 minutes of initiator Open 1 SG PORV or 1 bank of steam dumps within 25 minutes of initiator N/A Within t hour of pressurizer level 32 ft N/A 1ot2 RHR pumps to 2of2 intact legs N/A N/A
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SUMMARY
Table 14'- Success Griteria for SGTR Path Name CVGS SI AFT/I' SL AFWS BF
.,,s$l r RWST RHR RECIRC Mission Time 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> 36 hours 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> H/A N/A NIA N/A 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> 36 hours 33 hours3.819444e-4 days <br />0.00917 hours <br />5.456349e-5 weeks <br />1.25565e-5 months <br /> 24, hours SGTR.O17 N/A 1 of 2 Sl pumps to 4of4 legs IofZMDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG lsolate ruptured SG within 15 minutes of initiator Open 1 SG PORV or 1 bank of steam dumps within 25 minutes of initiator N/A Within t hour of pressurizer level 32 ft N/A FAILED N/A CST refill SGTR-o19 N/A 1 of 2 Sl pumps to 4of4 legs lof2MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG lsolate ruptured SG within 15 minutes of initiator Open 1 SG PORV or 1 bank of steam dumps within 25 minutes of initiator N/A FAILED RWST refill N/A N/A N/A SGTR-02O N/A 1 of 2 Sl pumps to 4of4 legs lof2MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG lsolate ruptured SG within 15 minutes of initiator Open 1 SG PORV or 1 bank of steam dumps within 25 minutes of initiator N/A FAILED FAILED N/A N/A CST refill SGTR.O22 N/A 1 of 2 Sl pumps to 4ot4 legs lof2MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG lsolate ruptured SG within 15 minutes of initiator FAILED N/A N/A RWST refill N/A N/A N/A SGTR-023 N/A 1 of 2 Sl pumps to 4ot4 legs lof2MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG lsolate ruptured SG within 15 minutes of initiator FAILED N/A N/A FAILED N/A N/A CST refill SGTR-025 N/A 1 of 2 Sl pumps to 4of4 legs lofZMDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG FAILED N/A N/A N/A RWST refill N/A N/A N/A
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Table {4 --,$IIG*tss Criteria for SGTR Path Name CVCS SI AFIIV st
- AFYtf6 BF.
ssr RWST RHR RECIRC LTHR Mission Time 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> 36 hours 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> N/A t{/A MA..
NIA 38 hours4.398148e-4 days <br />0.0106 hours <br />6.283069e-5 weeks <br />1.4459e-5 months <br /> 33,hours
,24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> SGTR-026 N/A 1 of 2 Sl pumps to 4of4 legs lof2MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG FAILED N/A N/A N/A N/A N/A N/A CST refill SGTR-028 N/A 1 of 2 Sl pumps to 4of4 legs FAILED N/A N/A 1 of 2 Safety lnjection pumps, 2 PZR PORVs within 30 minutes of FR.H.1 N/A N/A N/A 1 of 2 Sl pumps to 4 of 4 intact legs supported by 1 of 2 RHR pumps taking suction from the sump N/A SGTR.O31 FAILED FAILED 1of 2 MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG lsolate ruptured SG within 15 minutes of initiator Open 1 SG PORV or 1 bank of steam dumps within 25 minutes of initiator N/A N/A N/A 1of 2 RHR pumps to 2of2 intact legs N/A N/A SGTR.O32 FAILED FAILED lof2MDAFW pumps or 1 of 1 TD AFW pump to 1 unaffected SG lsolate ruptured SG within 15 minutes of initiator Open 1 SG PORV or 1 bank of steam dumps within 25 minutes of initiator N/A N/A N/A FAILED N/A CST refill Reference 35, Table 7.9-1
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Path Name MRI AM AFlOS AFSO SR LTS LTHR Mission Time N/A NIA AFW purnps rnUst be available and iniecting for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> N/A t hour ATWS-OO1 Rod insertion is successful AMSAC is successful 2of 2MD AFW pumps and 1 of 1 TD AFW pump to 4 of 4 SGs N/A 3 of 3 pressurizer safety valves and required pressurizer PORVs Successful Emergency Boration N/A ATWS-OO2 Rod insertion is successful AMSAC is successful 2 ot2MD AFW pumps and 1 of 1 TD AFW pump to 4 of 4 SGs N/A 3 of 3 pressurizer safety valves and required pressurizer PORVs FAILED CST refill ATWS-OO5 Rod insertion is successful AMSAC is successful FAILED 2of2MDAFWorlofl TDAFWorl of 2MD AFW and 1 of 1 TD AFW to 4 of 4 SGs 3 of 3 pressurizer safety valves and required pressurizer PORVs Successful Emergency Boration N/A ATWS.OO6 Rod insertion is successful AMSAC is successful FA!LED 2of 2MDAFWorl of 1 TDAFWorl of 2 MD AFW and 1 of 1 TD AFW to 4 of 4 SGs 3 of 3 pressurizer safety valves and required pressurizer PORVs FAILED CST refill ATWS-o11 FAILED AMSAC is successful 2of zMD AFW pumps and 1 of 1 TD AFW pump to 4 of 4 SGs N/A 3 of 3 pressurizer safety valves and required pressurizer PORVs Successful Emergency Boration N/A
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Path Name MRI AM LTS LTHR Mission Time N/A N/A AFW purnps must be'availEble and iniectin g tor 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> AFW pumps rnust'S available and iniec'tfng for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> t hour 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> ATWS-012 FAILED AMSAC is successful 2ot2MD AFW pumps and 1 of 1 TD AFW pump to 4 of 4 SGs N/A 3 of 3 pressurizer safety valves and required pressu nzer PORVs FAILED CST refill ATWS-o15 FAILED AMSAC is successful FAILED 2of 2MD AFWorl of 1 TDAFWorl of 2 MD AFW and 1 of 1 TD AFW to 4 of 4 SGs 3 of 3 pressurizer safety valves and required pressurizer PORVs Successful Emergency Boration N/A ATWS-o16 FAILED AMSAC is successful FAILED 2of2MDAFWorlofl TDAFWorl of 2MD AFW and 1 of 1 TD AFW to 4 of 4 SGs 3 of 3 pressurizer safety valves and required pressurizer PORVs FAILED CST refill Reference 35, Table 7.10-1
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Table 16 -- Success Griteria for ISLOCA Path Name CVCS SI STL AFW LTHR BF HPR RWST Mission Time 24 hourc N/A 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> t:
12 hsurs N/A 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> 24 hours ISLM-OO1 1 of 2 CVCS pumps to 4 of 4 legs N/A Path Isolation 1ot2 MD AFW pumps orloflTD AFW pump to 1SG CST refil!
N/A N/A N/A ISLM-OO2 1 of 2 CVCS pumps to 4 of 4 legs N/A Path lsolation 1of 2 MD AFW pumps orloflTD AFW pump to 1SG FAILED 1 ot 2 CVCS pumps, 1 PZR PORV within 15 minutes of 26% SG WR 1 of 2 CVCS pumps, 1 of 2 RHR pumps to 4 of 4legs N/A tsLM-005 1 of 2 CVCS pumps to 4 of 4 legs N/A Path lsolation FAILED N/A 1 of 2 CVCS pumps, 1 PZR PORV within 15 minutes of 26% SG WR 1 of 2 CVCS pumps, 1 of 2 RHR pumps to 4 of 4legs N/A rsLM-008 1 of 2 CVCS pumps to 4 of 4 legs N/A FAILED FAILED N/A N/A N/A RWST refill
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Table Path Name CVCS SI STL AFW LTHR BF FtPR RVTIST Mission Time 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />
,24 hourui N/A 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> 18 hours 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> rsLM-o10 FAILED 1of2Sl pumps to 4 of 4 legs Path lsolation 1of 2 MD AFW pumps orloflTD AFW pump to 1SG CST refill N/A N/A N/A rsLM-011 FAILED 1of2Sl pumps to 4 of 4 legs Path Isolation 1of 2 MD AFW pumps orloflTD AFW pump to 1SG FAILED 1 of 2 Safety Injection pumps, 2 PZR PORVs within 30 minutes of 260/o SG WR 1 of 2 Safety lnjection pumps, 1 of 2 RHR pumps to 4 of 4legs N/A tsLM-o14 FAILED 1of2Sl pumps to 4 of 4 legs Path lsolation FAILED N/A 1 of 2 Safety
!njection pumps, 2 PZR PORVs within 30 minutes of 260/o SG WR 1 of 2 Safety lnjection pumps, 1 of 2 RHR pumps to 4 of 4legs N/A rsLM-o17 FAILED 1of2Sl pumps to 4 of 4 legs FAILED FAILED N/A N/A N/A RWST refill Reference 35, Table 7. 11-1
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CPNPP Delta Accumulators 2 of 4 accumulators to 2 of 4 cold legs 3 of 3 accumulators to 3 of 3 intact cold legs MAAP 4.0.5 analysis cannot determine the success of accumulators in break sizes greater than 10 inches. Therefore, the success criteria must be determined from the UFSAR (Section 15.4 of Reference 3).
Low Pressure lnjection 1 of 2 RHR pumps to 1 of 4 cold legs 1 of 2 RHR pumps to 3 of 3 intact cold legs The results cannot justify 1 of 4loops based on flow balancing that limits flow through a single loop.
Cold Leg Low Pressure Recirculation 1 of 2 RHR pumps to 1 of 4 cold legs 1 of 2 RHR pumps to 1 of 2 intact cold legs During recirculation mode, the RHR pumps can only discharge to 2 RCS leqs.
Hot Leg Low Pressure Recirculation 1 of 2 RHR trains or 1 of 2 Sl trains 1 of 2 RHR pumps to 2 of 4 legs and 1 of 2 SI pumps to 2 of 4legs The WBN success criteria is correct per Reference 2.
Reference 35, Appendix B
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GPNPP Delta AFW 1 of 2 MD AFW pumps or 1 TD AFW pump to 1 of 4 SGs 1 of 2 MD AFW pumps or 1 TD AFW pump to 1 of 4 SGs No delta.
High pressure injection (CCPs) 1 of 2 centrifugal charging pumps to 1 of 4 cold legs lof2CVCSto3of3 cold legs The results cannot justify 1 of 4loops based on flow balancing that Iimits flow through a single loop.
High pressure injection (SIPs) 1 of 2 Safety lnjection Pumps to 1 of 4 cold legs 1 of 2 Sl pumps to 3 of 3 cold legs The results cannot justify l of 4loops based on flow balancing that limits flow through a single loop.
Secondary depressurization and Secondary heat removal 1 of 4 Atmospheric Relief Valves or 1 of 3 Banks of Steam Dump Valves 1 of 4 SG PORVs or 1 Bank of Steam Dumps No delta.
Accumulator Injection 2 oI4 Accumulators to 2 of 4 cold legs Not credited The accumulators are not credited in this model.
Low pressure injection 1 of 2 RHR pumps to 1 of 4 cold legs 1 of 2 RHR pumps to 3 of 3 cold legs The results cannot justify 1 of 4loops based on flow balancing that limits flow through a sinqle loop.
Cold leg low pressure recirculation 1 of 2 RHR trains from the containment sump to 1 of 4 cold legs 1 of 2 RHR pumps taking suction from the containment sump to 1 of 2 cold leqs During recirculation mode, the RHR pumps Gan only discharge to 2 RCS leqs.
Hot leg low pressure recirculation 1 of 2 RHR trains in hot leg recirculation from the containment sump to 1 of 4 hot legs Not required Hot leg recirculation is not required for MLOCAS because the water in the core does not deplete to the levels of a LLOCA. LLOCAs require hot leg recirculation because the water leaves the core very rapidly and the boron concentration may reach its solubility limits very quickly.
However with a MLOCA, the water in the core does not evacuate as quickly.
(Reference 13)
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MLOGA CPNPP
,'Delta Long term cooling 1 of 2 RHR trains to 1 of 4 cold legs taking suction from the containment sump Credited via low pressure reci rculation No delta.
High pressure recirculation No information 1 of 2 CVCS pumps or 1 of 2 SI pumps aligned to 1 of 2 RHR pumps For a MLOCA, high pressure recirculation is required (and gives success) when only the high pressure ECCS pumps are available.
Reference 35, Appendix B
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CPNPP iWBH
'Delta Auxiliary Feedwater 1 of 2 MD pumps or 1 TD pump to 1 of 4 SGs 1 of 2 MD pumps or 1 TD pump to 1 of 4 SGs No delta.
High pressure injection (CCPs) 1 of 2 centrifugal charging pumps to 1 of 4 cold legs lof2CVCSto3of3 cold legs The results cannot justify 1of 4loops based on flow balancing that limits flow through a single loop.
High pressure injection (SIPs) 1 of 2 Safety lnjection Pumps to 1 of 4 cold legs 1 of 2 Sl pumps to 3 of 3 cold legs The results cannot justify 1of 4loops based on flow balancing that limits flow through a sinqle loop.
Secondary Depressurization and Secondary Heat Removal 1 of 4 Atmospheric Relief Valves or 1 of 3 Banks of Steam Dumps Valves 1 of 4 SG PORVs or 1 Bank of Steam Dumps No delta.
Bleed and Feed 1 CCP and 1 SIP and 1 PZR PORV 1 of 2 CVCS pumps and 1 PZR PORV or 1 of 2 SI pumps and 2 PZR PORVs The CPNPP success criteria is based on conservative !icensing basis analysis. WBN is based on realistic analysis.
Accumulator injection 2 of 4 accumulators to 1 of 4 cold legs Not credited The accumulators not credited in model.
are this Low pressure injection 1 of 2 RHR pumps to 1 of 4 cold legs 1 of 2 RHR pumps to 3 of 3 cold legs The results cannot justify 1of 4loops based on flow balancing that limits flow through a single loop.
High pressure cold leg recirculation 1of?CCPto1of4 cold legs and 1 of 2 RHR trains taking suction from the containment sumps and providing suction flow to the available CCP 1 of 2 SlPs to 1 of 4 cold legs and 1 of 2 RHR trains taking suction from the containment sumps and providing suction flow to the available SIP 1 of 2 CVCS pumps to 3 of 3 cold legs aligned to 1 of 2 RHR pumps taking suction from the containment sump 1 of 2 Sl pumps to 1 of 4 cold legs aligned to 1 of 2 RHR pumps taking suction from the containment sump The results cannot justify 1of 4loops based on flow balancing that limits flow through a single loop.
Low pressure cold leg recirculation 1 of 2 RHR trains to 1 of 4 cold legs taking suction from the containment sump 1 of 2 RHR pumps taking suction from the containment sump delivering to 2 of 2 cold leqs During recirculation mode, the RHR pumps can only discharge lo 2 RCS legs.
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GPNPP WBN
[I6lts Long term RHR shutdown cooling 1 of 2 RHR trains to 1 of 4 cold legs taking suction from the containment sump Credited via low pressure reci rculation No delta.
Reference 35, Appendix B
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CPNPP WBH Delta Main Feedwater 1 of 2 main feedwater pumps to 1 of 4 SGs Not credited Main feedwater is not credited in this analysis.
Given a reactor trip (the first node in SLOCAV Event Tree), the main feedwater will terminate.
Auxiliary Feedwater 1 of 2 MD AFW pumps or 1 TD AFW pump to 1 of 4 SGs 1 of 2 MD AFW pumps orlTDpumptolof4 SGs No delta.
High pressure injection (CcPs) 1 of 2 centrifugal charging pumps to 1 of 4 cold legs 1 of 2 CVCS pumps to 4 of 4 cold legs The results cannot justify 1of 4loops based on flow balancing that limits flow through a single loop.
High pressure injection (SIPs) 1 of 2 safety injection pumps to 1 of 4 cold leos Not credited This analysis models normal charging and ECCS charqinq.
Secondary Depressurization and Secondary Heat Removal 1 of 4 Atmospheric Relief Valves or 1 of 3 banks of Steam Dump Valves 1 of 4 SG PORVs or 1 Bank of Steam Dumps No delta.
Bleed and Feed 1 CCP and 1 SIP and 1 PORV or 2 CCPs and 1 PORV 1 of 2 CVCS pumps and 1 PZR PORV or 1 of 2 Sl pumps and 2 PZR PORVs The CPNPP success criteria is based on conservative licensing basis analysis. WBN is based on realistic analvsis.
Low pressure injection 1 of 2 RHR pumps to 1 of 4 cold legs 1 of 2 RHR pumps to 4 of 4 cold legs The results cannot justify 1of 4loops based on flow balancing that limits flow through a single
!oop.
High pressure cold leg recirculation lof2CCPstolof4 cold legs and 1 of 2 RHR trains taking suction from the containment sumps and providing suction flow to the available CCP lofzSlPstolof4 cold legs and 1 of 2 RHR trains taking suction from the containment sumps and providing suction flow to the available SIP 1 of 2 CVCS pumps to 4 of 4 cold legs aligned to 1 of 2 RHR pumps taking suction from the containment sump 1 of 2 SI pumps to 4 of 4 cold legs aligned to 1 of 2 RHR pumps taking suction from the containment sump The results cannot justify 1of 4loops based on flow balancing that limits flow through a single loop.
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SLOGAV CPNPP WBN Low pressure cold leg recirculation 1 of 2 RHR trains to 1 of 4 cold legs taking suction from the containment sump and providing flow to the available CCP or SIP 1 of 2 RHR pumps taking suction from the containment sump delivering to 2 of 2 cold legs During recirculation mode, the RHR pumps can only discharge lo 2 RCS legs.
Long term RHR shutdown cooling 1 of 2 RHR trains to 1 of 4 cold legs taking suction from the containment sump Credited via low pressure reci rculation No delta.
Reference 35, Appendix B
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GPNPP UUBN Delta Main Feedwater 1 of 2 main feedwater pumps to 1 of 4 SGs Not credited Main feedwater is not credited in this analysis.
Given a reactor trip (the first node in GTRAN Event Tree), the main feedwater will terminate.
Auxiliary Feedwater 1 of 2 MD AFW pumps or 1 TD AFW pump to 1 of 4 SGs 1 MD AFW pump or 1 TD pump to 1 of 4 SGs No delta.
Condensate 1 of 2 condensate pumps to 1 of 4 SGs Not credited Condensate pumps are not credited in this model.
High pressure injection (CCPs) 1 of 2 centrifugal charging pumps to 1 of 4 cold leqs Not credited This analysis does not credit high pressure iniection.
High pressure injection (SIPs) 1 of 2 safety injection pumps to 1 of 4 cold leqs Not credited This analysis does not credit high pressure iniection.
Secondary depressurization and heat removal 1 of 3 AFW pumps (ITDAFW or 1 ot 2 MDAFW) or 1 of 2 MFW pumps to 1 of 4 Steam Generators 1 of 2 MD AFW pumps orlTDpumptolof4 SGs No delta.
Bleed and Feed 1 centrifugal charging pump (CCP) and 1 safety injection pump (SlP) and 1 PORV or 2 CCPs and 1 PORV 1 of 2 CVCS pumps and 1 PZR PORV or 1 of 2 Sl pumps and 2 PZR PORVs The CPNPP success criteria is based on conservative Iicensing basis analysis. WBN is based on realistic analysis.
High pressure recirculation lof2CCPstolof4 cold legs and 1 of 2 RHR trains taking suction from the containment sumps and providing suction flow to the available CCP lof2SlPstolof4 cold legs and 1 of 2 RHR trains taking suction from the containment sumps and providing suction flow to the available SIP 1 of 2 CVCS pumps to 4 of 4 cold legs aligned to 1 of 2 RHR pumps taking suction from the containment sump 1 of 2 SI pumps to 4 of 4 cold legs aligned to 1 of 2 RHR pumps taking suction from the containment sump The results cannot justify 1of 4loops based on flow balancing that limits flow through a single loop.
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Table 21 ; SUucess Criteria Gomparison: Transient
, CPNPP WBN Low pressure recirculation 1 of 2 RHR trains to 1 of 4 cold legs taking suction from the containment sump and providing flow to the available CCP or SIP Not credited Low pressure recirculation is not credited in this model.
Long term RHR shutdown cooling 1 of 2 RHR trains to 1 of 4 cold legs taking suction from the containment sump and providing suction flow to the available CCP or SIP Credited via SGs or normal RHR Credit taken from transition to normal RHR cooling.
Reference 35, Appendix B
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GPNPP IlllBhl.,'.
Delta SG Isolation lsolate AFW and Main Steam on the faulted SG Operator ldentifies and isolates the ruptured SG No delta.
Main Feedwater 1 of 2 main feedwater pumps to 1 of 4 SGs Not credited Main feedwater is not credited in this analysis.
Given a reactor trip (the first node in SGTR Event Tree), the main feedwater will terminate.
Auxiliary Feedwater 1 of 2 MD AFW pumps or 1 TD AFW pump to 1 of 4 SGs 1 of 2 MD AFW pumps orlTDAFWtolof3 unaffected SGs No delta.
Condensate 1 of 2 condensate pumps to 1 of 4 SGs Not credited Condensate pumps not credited in model.
are this High pressure injection (CCPs) 1 of 2 centrifugal charging pumps to 1 of 4 cold legs 1 of 2 CVCS pumps to 4 of 4 cold legs The results cannot justify 1of 4loops based on flow balancing that Iimits flow through a single loop.
High pressure injection (SlPs) 1 of 2 Safety lnjection Pumps to 1 of 4 cold Iegs 1 of 2 SI pumps to 4 of 4 cold legs The results cannot justify 1of 4loops based on flow balancing that limits flow through a single loop.
Secondary Depressurization and Heat removal 1 of 3 AFW pumps or 1 of 2 MFW pumps to 2 INTACT Steam Generators and Steam Relief with 2 of 4 ARVs on INTACT Steam Generators with successful feedwater makeup or 1 of 3 Banks of Steam Dump valves 1 of 2 MD AFW pumps or 1 TD AFW pump to 1 of 3 intact SGs and 1 of 3 SG PORVs No credit taken for the steam dumps.
Bleed and Feed 1 CCP and 1 SIP and 1 PORV or 2 CCPs and 1 PORV 1 of 2 CVCS pumps and 1 PZR PORV or 1 of 2 Sl pumps and 2 PZR PORVs The CPNPP success criteria is based on conservative licensing basis analysis. WBN is based on realistic analysis.
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SGTR.
CPNPP WBN High pressure recirculation 1of?CCPto1of4 cold legs and 1 of 2 RHR trains taking suction from the containment sumps and providing suction flow to the available CCP 1of 2 SlPto 1 ot4 cold legs and 1 of 2 RHR trains taking suction from the containment sumps and providing suction flow to the available SIP 1 of 2 CVCS pumps to 4 of 4 cold legs aligned to 1 of 2 RHR pumps taking suction from the containment sump 1 of 2 Sl pumps to 4 of 4 cold legs aligned to 1 of 2 RHR pumps taking suction from the containment sump The results cannot justify 1of 4loops based on flow balancing that Iimits flow through a single Ioop.
Low pressure recirculation 1 of 2 RHR trains to 1 of 4 cold legs taking suction from the containment sump and providing flow to the available CCP or SIP No credited.
Low pressure recirculation is not credited in this model.
Long term RHR shutdown cooling 1 of 2 RHR trains to 1 of 4 cold legs taking suction from the containment sump or 1 of 3 AFW pumps to 1 of 4 SGs with long term suction from 1of 2 Station Service Water supply lines 1 of 2 RHR pumps taking suction from the hot leg and discharging into the cold leg.
No delta.
Reference 35, Appendix B
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MffiF Run ldentifier BF-A 3/8 inch equivalent break modeling success path SLOCA-008 BF-B 3/8 inch equivalent break modeling success path SLOCA-O18 BFC Bleed and Feed Requirements, BFD Bleed and Feed Requirements, BFE Bleed and Feed Requirements, BF-F Bleed and Feed Requirements, BF-G Bleed and Feed Requirements, GTRAN C Models success path GTRAN-001 GTRAN C 4SG Reactor Trip at time zero with AFW delivered to 4 SG GTRAN D CST depletion time ISLOCA C Models success path ISLM-001 ISLOCA D Models success path ISLM-002 ISLOCA E Models success path ISLM-005 ISLOCA F Models success path ISLM-008 ISLOCA J Models success path ISLM-010 ISLOCA_K Models success path ISLM-O11 ISLOCA-M Models success path !SLM-017 L2-ARF6.inp Supports ARF model L2-Basecasebf.inp SLOCA with delayed B&F. AII systems available.
L2-CS2.inp SLOCA with loss of AFW, lC available.
L2-CS4C.inp SLOCA with failed HPR, produces approximately 900 lbs Hz.
L2-Ex-vessel.inp 6 inch LOCA with ex-vessel cooling is enabled.
L2-Ex-vesse!1.inp 2 inch LOCA with ex-vessel cooling is enabled.
L2-Ex-vessel2.inp 6 inch LOCA with ex-vessel cooling is disabled.
L2-Ex-vessel3.inp 2 inch LOCA with ex-vessel cooling is disabled.
L2_GTRAN2.inp General Transient produces 550 lbs of H2 L2_GTRAN2A.inp General Transient with 15 v/o Hz at vessel breach Containment peak pressure of 26.6 psia L2_GTRAN2c.inp General Transient with igniters available
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Containment peak pressure of 45.5 psia L2 GTRAN2D.inp General Transient with 12 vlo H2 at vessel breach L2-H2det.inp Supports ARF model L?-HLCreep2.inp Supports ARF model L?-HLCreep3.inp Supports ARF model L2-lC2.inp lnitial ice mass available with inlet doors unavailable.
SLOCA with loss of AFW; CS available.
L2-lC_lDD4.inp Initial ice mass available with 4 intermediate deck doors.
L2-lC-LlD2.inp lnitial ice mass available with 2 sets of lower inlet doors L2-lC_LlD4.inp lnitial ice mass available with 4 sets of lower inlet doors L2-!C_LID6.inp lnitial ice mass available with 6 sets of lower inlet doors L2-lC_TDD4.inp lnitial ice mass available with 4 top deck doors.
L2-lC_SC.inp lnitial ice mass with 4 sets of lower inlet doors, 4 intermediate deck doors, and 4 top deck doors.
L2-lgniter3A.inp Supports ARF mode!
L2_LLOCMA.inp Supports ARF model L2_LLOCA2B.inp Supports ARF model L2 LLOCA4c.inp LLOCA with no ECCS mitigation.
L2-RCP3.inp SBO conditions with 480 gpm RCP seal LOCA L2-RCP3b.inp SBO with RCP sea! LOCA L2-RCP6cc.inp RCP Seal LOCA at 480 gpm L2_SBO.inp SBO produces approximately 500 lbs of Hz. (Standard Parameters)
Containment peak pressure of 51 psia L2-SBO5.inp SBO conditions that give DCH with any vessel failure L2_S806.inp SBO conditions that give DCH with only creep vessel failure L2_SBO1 f.inp SBO case without Seal Table failure modeled.
SBO produces approximately 500lbs Hz.
Simultaneous HPME and H2 burns. Produces highest containment pressure
= 80 psia (Temp Spike = 900'F).
Containment peak pressure of 81 psia L2_SBO12.inp SBO case with Seal Table failure modeled.
L2_SBO13.inp SBO with power recovery produces approximately 600 lb H2
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Table 2!
- MAAP Runs MAAP Run ldentifler ln-core H2 generation of 570 lbs L2_SBOA_4ACC.inp ln-core H2 generation of 533 lbs L2_SBOc.inp SBO with igniters available Containment peak pressure of 51 psra L2_SBOe.inp SBO produces approximately 560 lbs of Hz L2-WB_SBO_1.inp Supports ARF model LLOCA A 6 inch equivalent break modeling success path LLOCA-001 LLOCA B 10 inch equivalent break modeling success path LLOCA-001 LLOCA E 6-inch mission time for LLOCA LLOCA F Minimum recirculation time; RWST depletion LLOCA G Hot leg recirculation LLOCA M Design Basis Accident modeling success path LLOCA-001 MLOCA A 6 inch equivalent break modeling success path MLOCA-001 MLOCA B 2 inch equivalent break modeling success path MLOCA-001 MLOCA C 6 inch equivalent break modeling success path MLOCA-006 MLOCA D 2 inch equivalent break modeling success path MLOCA-006 MLOCA E 2 inch equivalent break modeling success path MLOCA-007 MLOCA F Minimum recirculation time MLOCA G 6 inch equivalent break modeling success path MLOCA-007 MLOCA-H 2 inch, LPR time with containment spray MLOCA-J 2 inch equivalent break modeling success path MLOCA-01 1 MLOCA_K 6 inch, LPR time with containment spray MLOCA-L 6 inch equivalent break modeling success path MLOCA-O11 MLOCA-M 6 inch, LPR time with containment spray MLOCA-N 2 inch, LPR time with containment spray MLOCA P 2 inch equivalent break modeling success path MLOCA-002 MLOCA O 6 inch equivalent break modeling success path MLOCA-002 MLOCA R 2 inch, HPR time with containment spray MLOCA S 6 inch, HPR time with containment spray MLOCA T 2 inch, HPR time with containment spray MLOCA U 6 inch, HPR time with containment spray
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Table 23 - MAAP Rune MAAP Run ldentlfler Description MLOCA V Operator fails to decrease RCS MSA Transient Bleed and Feed MS-B Transient Bleed and Feed RCP_A.inp RCP seal leaks compared to LOCA RCP_B.inp RCP seal leaks compared to LOCA RCP_C.inp RCP seal leaks compared to LOCA RCP_D.inp RCP seal leaks compared to LOCA RCP_E.inp RCP seal leaks compared to LOCA RCP_F.inp RCP seal leaks compared to LOCA SBO-A Models AFW, 4 hr battery time, 21 gpm per pump seal LOCA, Do AC power recovery SBO_B Models AFW, 4 hr battery time, 182 gpm per pump seal LOCA, no AC power recovery SBO-C Models AFW, 4 hr baftery time, 480 gpm per pump seal LOCA, no AC power recovery SBO-D Models AFW and RCS cooldowh, 4 hr battery time, 21 gpm per pump seal LOCA, ro AC power recovery SBO-E Models AFW and RCS cooldowh, 4 hr battery time, 182 gpm per pump seal LOCA, ho AC power recovery SBO-F Models AFW and RCS cooldowr, 4 hr battery time, 480 gpm per pump seal LOCA, ro AC power recovery SBO G Models AFW and RCS cooldowh, 8 hr battery time, 21 gpm per pump seal LOCA, ro AC power recovery SBO H Models AFW and RCS cooldowh, 8 hr battery time, 182 gpm per pump seal LOCA, ho AC power recovery SBO J Models 21 gpm per pump seal LOCA, ro AC power recovery SBO-K Models 182 gpm per pump seal LOCA, ro AC power recovery SBO L Models 480 gpm per pump seal LOCA, ro AC power recovery SBO_M Models AFW, 8 hr battery time, 21 gpm per pump seal LOCA, ho AC power recovery SBO_N Models AFW, I hr battery time, 182 gpm per pump seal LOCA, no AC power recovery SBO-P Models AFW, 8 hr battery time, 480 gpm per pump seal LOCA, no AC power recovery SBO O Models AFW and RCS cooldowr, 8 hr battery time, 480 gpm per pump seal
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LOCA, flo AC power recovery SGTR-A Charging pumps with AFW SGTR-AA Models success path SGTR-005 SGTR AB Models success path SGTR-020 SGTR AC Models success path SGTR-008 SGTR AD Models success path SGTR-023 SGTR AE Models success path SGTR-026 SGTR B Sl pump with AFW SGTR C Charging pumps with no AFW SGTR E RCS depressurization SGTR F CST depletion times SGTR G CST depletion times SGTR H Models success path SGTR-001 SGTR K Models success path SGTR-013 SGTR-L Sl pump with AFW SGTR_M Models success path SGTR-028 SGTR_N Models success path SGTR-004 SGTR-P RWST refill SGTR-Q Models success path SGTR-032 SGTR-R Models success path SGTR-O16 SGTR-S Models success path SGTR-017 SGTR-T Models success path SGTR-019 SGTR-U Models success path SGTR-022 SGTR-V Models success path SGTR-025 SGTR_W Models success path SGTR-031 SGTR-X Models success path SGTR-010 SGTR Y Models success path SGTR-007 SGTR Z Models success path SGTR-002 SGTR27 Models success path SGTR-01 1 SLB_A Pressurizer Overfill SLOCA-A 2 inch equivalent break modeling success path SLOCA-001
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Table 23 - MAAP Runs MAAP Run ldentifler Descriptlon SLOCA B 3/8 inch equivalent break modeling success path SLOCA-001 SLOCA_C 2 inch equivalent break modeling success path SLOCA-01 1 SLOCA-D 3/8 inch equivalent break modeling success path SLOCA-011 SLOCA-E 2 inch equivalent break modeling success path SLOCA-013 SLOCA-ECS SLOCA with containment spray and LPR SLOCA F 3/8 inch equivalent break modeling success path SLOCA-O13 SLOCA FCS SLOCA with containment spray and LPR SLOCA-G 3/8 inch equivalent break modeling success path SLOCA-003 SLOCA GCS SLOCA with containment spray and LPR SLOCA H 2 inch equivalent break modeling success path SLOCA-003 SLOCA HCS SLOCA with containment spray and LPR SLOCA J CST depletion times with charging injection SLOCA K CST depletion times with Sl injection SLOCA L Recirculation switchover times SLOCA-M 3/8 inch equivalent break modeling success path SLOC A-021 SLOCA_MCS SLOCA with containment spray and LPR SLOCA-N 2 inch equivalent break modeling success path SLOC A-021 SLOCA-NCS SLOCA with containment spray and LPR SLOCA-P 2 inch, ho depressurization, core damage SLOCA O 318 inch, ro depressurization, core damage SLOCA-S Operator fails to depressurize RCS SLOCA-T SLOCA with containment spray and HPR SLOCA-U SLOCA with containment spray and HPR SLOCA-V SLOCA with containment spray and HPR SLOCA-W SLOCA with containment spray and HPR SLOCA-X SLOCA with containment spray and HPR SLOCA-Y Modeling success path SLOCA-006 SLOC A-Z Modeling success path SLOCA-O16 SLOCAV A Models success path SLOCAV-0O1 SLOCAV B Models success path SLOCAV-OOS SLOCAV C Plant response, no operator actions modeled
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SLOCAV D Blocked Sl signal SLOCAV-E Long term cooling with RHR SLOCAV-F Success with 1/8 inch equivalent break size SLOCAV G Success with 1/8 inch equivalent break size SLOCAV J Models success path SLOCAV-OO2 SLOCAV K Models success path SLOCAV-00S SLOCAV N Models success path SLOCAV-OO9 SLOCAV P Models success path SLOCAV-O12 SSBI-OO1 Models success path SSBI-001 SSBI-OO2 Models success path SSBI-002 SSBI-006 Models success path SS8I-006 SSBI-OO9 Models success path SSBI-009 SSBI.OI 1 Models success path SSBI-01 1 ssBt-o12 Models success path SSBI-012 ssBr-o15 Models success path SSBI-015 SSBI-015A Charging pump bleed and feed SSBI-018 Models success path SSBI-018 SSBI-019 Models success path SSBI-019 ssBr-023 Models success path SSBI-023 ssBr-026 Models success path SS8I-026 ssBr-028 Models success path SSBI-028 ssBt-029 Models success path SSBI-029 ssBr-032 Models success path SSB!-032 SSBI-032A S! pump bleed and feed ssBr-035 Models success path SSBI-035 ssBo-o01 Models success path SSBO-001 ssBo-002 Models success path SSBO-002 ss80-006 Models success path 5S80-006 ssBo-009 Models success path SSBO-009 ssBo-o1 1 Models success path SSBO-01 1 ssBo-012 Models success path SSBO-012