RC-15-0100, Submittal of 2014 Emergency Core Cooling System (ECCS) Evaluation Model Revisions Annual Report

Submittal of 2014 Emergency Core Cooling System (ECCS) Evaluation Model Revisions Annual Report

ML15181A255
Person / Time
Site:	Summer
Issue date:	06/24/2015
From:	Gatlin T South Carolina Electric & Gas Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LTD 321, RC-15-0100, RR 8375
Download: ML15181A255 (18)

Text

Thomas D. Gatlin Vice President,Nuclear Operations 803.345.4342 June 24, 2015 A SCANA COMPANY Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555

Subject:

VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT I DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 ECCS EVALUATION MODEL REVISIONS REPORT South Carolina Electric & Gas Company (SCE&G), acting for itself and as agent for South Carolina Public Service Authority, hereby submits the 2014 Emergency Core Cooling System (ECCS) Evaluation Model Revisions Annual Report for VCSNS. This report is being submitted pursuant to 10 CFR 50.46, which requires licensees to notify the NRC on at least an annual basis of corrections to or changes in the ECCS Evaluation Models.

Summary sheets describing changes and enhancements to the ECCS Evaluation Models for 2014 are included in Attachment I. Peak Clad Temperature (PCT) sheets are included in Attachment I1.

If you have any questions, please call Bruce L. Thompson at (803) 931-5042.

Very truly yours, Thomas D. Gatlin TS/TDG/wm Attachments c: K. B. Marsh S. A. Williams S. A. Byrne NRC Resident Inspector J. B. Archie K. M. Sutton N. S. Carns NSRC J. H. Hamilton RTS (LTD 321, RR 8375)

J. W. Williams File (818.02-17)

W. M. Cherry PRSF (RC-15-0100)

V. M. McCree Acc)ýa'

,\'A4 V.C.Summer Nuclear Station P.O.Box 88 *Jenkinsville, SC .29065

• F(803) 941-9776

Document Control Desk Attachment I LTD 321 RC-1 5-0100 Page 1 of 6 Attachment I Changes and Enhancements to the ECCS Evaluation Models for 2014

Document Control Desk Attachment I LTD 321 RC-15-0100 Page 2 of 6 GENERAL CODE MAINTENANCE

Background

Various changes have been made to enhance the usability of codes and to streamline future analyses. Examples of these changes include modifying input variable definitions, units and defaults; improving the input diagnostic checks; enhancing the code output; optimizing active coding; and eliminating inactive coding. These changes represent Discretionary Changes that will be implemented on a forward-fit basis in accordance with Section 4.1.1 of WCAP-1 3451.

Affected Evaluation Models 1996 Westinghouse Best Estimate Large Break LOCA Evaluation Model 2004 Westinghouse Realistic Large Break LOCA Evaluation Model Using ASTRUM 1985 Westinghouse Small Break LOCA Evaluation Model with NOTRUMP Estimated Effect The nature of these changes leads to an estimated Peak Cladding Temperature (PCT) impact of 0°F.

Document Control Desk Attachment I LTD 321 RC-15-0100 Page 3 of 6 REVISED TOTAL CODE UNCERTAINTY IN BE LBLOCA MONTE CARLO SIMULATIONS

Background

As part of the WCOBRAJTRAC validation basis for use in Best-Estimate (BE) Large-Break Loss-of-Coolant Accident (LBLOCA) analysis, simulations of many separate effects tests (SETs) and integral effects tests (lETs) were performed. In the Westinghouse 1996 BE LBLOCA evaluation model (CQD evaluation model), the simulations of the test data which included core heat transfer measurements were used in the uncertainty methodology in two ways:

1. To develop heat transfer multiplier distributions which are used in the HOTSPOT code for local hot rod calculations.

2. To determine the minimum code uncertainties for blowdown and reflood that are used in the MONTECF code for the Monte Carlo uncertainty calculations.

The effects of several changes and error corrections to the WCOBRA/TRAC code were previously reported in 2013, including effects of revised heat transfer multiplier distributions. As a result of previously reported changes and error corrections made to WCOBRA/TRAC, the total code uncertainty values utilized in the MONTECF code for both blowdown and reflood were recalculated. The recalculated total code uncertainty values are lower than the previous values.

Resolution of this issue represents a Non-Discretionary Change in accordance with Section 4.1.2 of WCAP-13451.

Affected Evaluation Model 1996 Westinghouse Best Estimate Large Break LOCA Evaluation Model Estimated Effect The total code uncertainty value is essentially a minimum limit for the superposition correction in the Monte Carlo simulations performed with the MONTECF code. As a result, a reduction in the minimum superposition correction would be expected to produce a small benefit, and will thus be conservatively assigned a 0°F estimate of effect.

Document Control Desk Attachment I LTD 321 RC-15-0100 Page 4 of 6 FUEL ROD GAP CONDUCTANCE ERROR

Background

An error was identified in the fuel rod gap conductance model in the NOTRUMP computer code (reactor coolant system response model). The error is associated with the use of an incorrect temperature in the calculation of the cladding emissivity term. This error corresponds to a Non-Discretionary Change as described in Section 4.1.2 of WCAP-13451.

Affected Evaluation Model(s) 1985 Westinghouse Small Break LOCA Evaluation Model with NOTRUMP Estimated Effect The estimated effect was determined based on a combination of engineering judgment of the phenomena and physics of a small break LOCA and sensitivity calculations performed with the advanced plant version of NOTRUMP. It was concluded that this error has a negligible effect on small break LOCA analysis results, leading to an estimated Peak Cladding Temperature (PCT) impact of 0°F.

Document Control Desk Attachment I LTD 321 RC-1 5-0100 Page 5 of 6 RADIATION HEAT TRANSFER MODEL ERROR

Background

Two errors were discovered in the calculation of the radiation heat transfer coefficient within the fuel rod model of the NOTRUMP computer code (reactor coolant system response model).

First, existing logic did not preclude non-physical negative or large (negative or positive) radiation heat transfer coefficients from being calculated. These erroneous calculations occurred when the vapor temperature exceeded the cladding surface temperature or when the predicted temperature difference was less than 1OF. Second, a temperature term incorrectly used degrees Fahrenheit instead of Rankine. These errors represent a closely related group of Non-Discretionary problems in accordance with Section 4.1.2 of WCAP-13451.

Affected Evaluation Model(s) 1985 Westinghouse Small Break LOCA Evaluation Model with NOTRUMP Estimated Effect The estimated effect was determined based on a combination of engineering judgment of the phenomena and physics of a small break LOCA and sensitivity calculations performed with the advanced plant version of NOTRUMP. It was concluded that this error has a negligible effect on small break LOCA analysis results, leading to an estimated Peak Cladding Temperature (PCT) impact of 0°F.

Document Control Desk Attachment I LTD 321 RC-15-0100 Page 6 of 6 SBLOCTA PRE-DNB CLADDING SURFACE HEAT TRANSFER COEFFICIENT CALCULATION

Background

Two errors were discovered in the pre-departure from nucleate boiling (pre-DNB) cladding surface heat transfer coefficient calculation in the SBLOCTA code (cladding heat-up calculations). The first error is a result of inconsistent time units (hours vs. seconds) in the parameters used for the calculation of the Reynolds and Prandtl numbers, and the second error relates to an incorrect diameter used to develop the area term in the cladding surface heat flux calculation. Both of these issues impact the calculation of the pre-DNB convective heat transfer coefficient, representing a closely related group of Non-Discretionary Changes to the Evaluation Model as described in Section 4.1.2 of WCAP-1 3451.

Affected Evaluation Model(s) 1985 Westinghouse Small Break LOCA Evaluation Model with NOTRUMP Estimated Effect These errors have been corrected in the SBLOCTA code. Because this condition occurred prior to DNB, it was judged that these errors had no direct impact on the cladding heat-up related to the core uncovery period. A series of validation tests were performed and confirmed that these errors have a negligible effect on SBLOCA analysis results, leading to an estimated Peak Cladding Temperature (PCT) impact of 00 F.

Document Control Desk Attachment II LTD 321 RC-15-O100 Page 1 of 11 Attachment II Peak Clad Temperature (PCT) Rackup Sheets

Document Control Desk Attachment II LTD 321 RC-15-0100 Page 2 of 11 Westinghouse LOCA Peak Clad Temperature Summary for Best Estimate Large Break Plant Name: V. C. Summer Utility Name: South Carolina Electric & Gas Revision Date: 2/10/2015 Composite Analysis Information EM: CQD (1996) Analysis Date: 2/3/2003 Limiting Break Size: Guillotine FQ: 2.5 FdH: 1.7 Fuel: Vantage + SGTP (%): 10 Notes: Delta 75 Replacement Steam Generator Uprate Core Power 2900 MWt Clad Temp (°F) Ref. Notes LICENSING BASIS Analysis-Of-Record PCT 1988 1 PCT ASSESSMENTS (Delta PCT)

A. PRIOR ECCS MODEL ASSESSMENTS

1. Backfit Through 2001 Reporting Year 0 2

2. Revised Blowdown Heatup Uncertainty Distribution 5 3

3. PAD 4.0 Implementation -118 6

4. Evaluation of Fuel Pellet Thermal Conductivity 123 6 (a)

Degradation and Peaking Factor Burndown

5. Transverse Momentum Cells for Zero 0 6 (b)

Cross-flow Boundary Condition Error

6. Revised Heat Transfer Multiplier Distributions -35 7

7. Changes to Grid Blockage Ratio and Porosity 24 8

8. Error in Burst Strain Application 0 9 B. PLANNED PLANT MODIFICATION EVALUATIONS

1. Fan Cooler Performance Increase 2 2

2. Upflow Conversion Evaluation -29 4

3. Additional Heat Sinks and Increased Spray Flow Rate 1 5 C. 2014 ECCS MODEL ASSESSMENTS

1. None 0 D. OTHER

1. None 0 LICENSING BASIS PCT + PCT ASSESSMENTS PC T= 1961 References

1. WCAP-1 6043, "Best Estimate Analysis of the Large Break Loss of Coolant Accident for the Virgil C. Summer Nuclear Station," June 2003.

2. CGE-03-12, "10 CFR 50.46 Annual Notification and Reporting for 2002," March 2003.

3. CGE-05-20, "10 CFR 50.46 Annual Notification and Reporting for 2004," April 2005.

4. LTR-LIS-08-578, Revision 2, "10 CFR 50.46 Reports for the V. C. Summer (CGE)

Upflow Conversion Large Break LOCA Evaluation and Assessment of Transverse Momentum Cells with a Zero Cross-flow Boundary Condition Error," January 2009.

5. CGE-10-29, "BELOCA Summary Report," November 2010.

6. LTR-LIS-12-372, "V. C. Summer, 10 CFR 50.46 Notification and Reporting for Fuel

Document Control Desk Attachment II LTD 321 RC-1 5-0100 Page 3 of 11 Pellet Thermal Conductivity Degradation and Peaking Factor Burndown,"

September 20, 2012.

7. LTR-LIS-13-353, "V. C. Summer 10 CFR 50.46 Report for Revised Heat Transfer Multiplier Distributions," July 2013.

8. LTR-LIS-13-476, "V. C. Summer 10 CFR 50.46 Report for Changes to Grid Blockage Ratio and Porosity," October 2013.

9. LTR-LIS-14-37, "V. C. Summer 10 CFR 50.46 Report for the HOTSPOT Burst Strain Error Correction," January 2014.

Notes:

(a) This evaluation credits peaking factor burndown; see Reference 6.

(b) This input error was originally reported in Reference 4. That evaluation is superseded by the report in Reference 6.

Document Control Desk Attachment II LTD 321 RC-1 5-0100 Page 4 of 11 Westinghouse LOCA Peak Clad Temperature Summary for Best Estimate Large Break Plant Name: V. C. Summer Utility Name: South Carolina Electric & Gas Revision Date: 2/10/2015 Blowdown Analysis Information EM: CQD (1996) Analysis Date: 2/3/2003 Limiting Break Size: Guillotine FQ: 2.5 FdH: 1.7 Fuel: Vantage + SGTP (%): 10 Notes: Delta 75 Replacement Steam Generator Uprate Core Power 2900 MWt Clad Temp (7F) Ref. Notes LICENSING BASIS Analysis-Of-Record PCT 1860 1 PCT ASSESSMENTS (Delta PCT)

A. PRIOR ECCS MODEL ASSESSMENTS

1. Backfit Through 2001 Reporting Year 0 2

2. Revised Blowdown Heatup Uncertainty Distribution 49 3

3. PAD 4.0 Implementation -83 6

4. Evaluation of Fuel Pellet Thermal Conductivity 0 6 (a)

Degradation and Peaking Factor Burndown

5. Transverse Momentum Cells for Zero Cross-flow 0 6 (b)

Boundary Condition Error

6. Revised Heat Transfer Multiplier Distributions -5 7

7. Changes to Grid Blockage Ratio and Porosity 0 8

8. Error in Burst Strain Application 0 9 B. PLANNED PLANT MODIFICATION EVALUATIONS

1. Fan Cooler Performance Increase 0 2

2. Upflow Conversion Evaluation -7 4

3. Additional Heat Sinks and Increased Spray Flow Rate 0 5 C. 2014 ECCS MODEL ASSESSMENTS

1. None 0 D. OTHER

1. None 0 LICENSING BASIS PCT + PCT ASSESSMENTS PC T= 1814 References

1. WCAP-1 6043, "Best Estimate Analysis of the Large Break Loss of Coolant Accident for the Virgil C. Summer Nuclear Station," June 2003.

2. CGE-03-12, "10 CFR 50.46 Annual Notification and Reporting for 2002," March 2003.

3. CGE-05-20, "10 CFR 50.46 Annual Notification and Reporting for 2004," April 2005.

4. LTR-LIS-08-578, Revision 2, "10 CFR 50.46 Reports for the V. C. Summer (CGE)

Upflow Conversion Large Break LOCA Evaluation and Assessment of Transverse Momentum Cells with a Zero Cross-flow Boundary Condition Error," January 2009.

5. CGE-10-29, "BELOCA Summary Report," November 2010.

Document Control Desk Attachment II LTD 321 RC-1 5-0100 Page 5 of 11

6. LTR-LIS-12-372, "V. C. Summer, 10 CFR 50.46 Notification and Reporting for Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown," September 20, 2012.

7. LTR-LIS-13-353, "V. C. Summer 10 CFR 50.46 Report for Revised Heat Transfer Multiplier Distributions," July 2013.

8. LTR-LIS-13-476, "V. C. Summer 10 CFR 50.46 Report for Changes to Grid Blockage Ratio and Porosity," October 2013.

9. LTR-LIS-14-37, "V. C. Summer 10 CFR 50.46 Report for the HOTSPOT Burst Strain Error Correction," January 2014.

Notes:

(a) This evaluation credits peaking factor burndown, see Reference 6.

(b) This input error was originally reported in Reference 4. That evaluation is superseded by the report in Reference 6.

Document Control Desk Attachment II LTD 321 RC-1 5-0100 Page 6 of 11 Westinghouse LOCA Peak Clad Temperature Summary for Best Estimate Large Break Plant Name: V. C. Summer Utility Name: South Carolina Electric & Gas Revision Date: 2/10/2015 Reflood 1 Analysis Information EM: CQD (1996) Analysis Date: 2/3/2003 Limiting Break Size: Guillotine FQ: 2.5 FdH: 1.7 Fuel: Vantage + SGTP (%): 10 Notes: Delta 75 Replacement Steam Generator Uprate Core Power 2900 MWt Clad Temp (°F) Ref. Notes LICENSING BASIS Analysis-Of-Record PCT 1808 1 PCT ASSESSMENTS (Delta PCT)

A. PRIOR ECCS MODEL ASSESSMENTS

1. Backfit Through 2001 Reporting Year 0 2

2. Revised Blowdown Heatup Uncertainty Distribution 5 3

3. PAD 4.0 Implementation -118 6

4. Evaluation of Fuel Pellet Thermal Conductivity 113 6 (a)

Degradation and Peaking Factor Burndown

5. Transverse Momentum Cells for Zero Cross-flow 0 6 (b)

Boundary Condition Error

6. Revised Heat Transfer Multiplier Distributions 5 7

7. Changes to Grid Blockage Ratio and Porosity 24 8

8. Error in Burst Strain Application 20 9 B. PLANNED PLANT MODIFICATION EVALUATIONS

1. Fan Cooler Performance Increase 1 2

2. Upflow Conversion Evaluation -44 4

3. Additional Heat Sinks and Increased Spray Flow Rate 0 5 C. 2014 ECCS MODEL ASSESSMENTS

1. None 0 D. OTHER

1. None 0 LICENSING BASIS PCT + PCT ASSESSMENTS PC T= 1814 References

1. WCAP-1 6043, "Best Estimate Analysis of the Large Break Loss of Coolant Accident for the Virgil C. Summer Nuclear Station," June 2003.

2. CGE-03-12, "10 CFR 50.46 Annual Notification and Reporting for 2002," March 2003.

3. CGE-05-20, "10 CFR 50.46 Annual Notification and Reporting for 2004," April 2005.

4. LTR-LIS-08-578, Revision 2, "10 CFR 50.46 Reports for the V. C. Summer (CGE)

Upflow Conversion Large Break LOCA Evaluation and Assessment of Transverse Momentum Cells with a Zero Cross-flow Boundary Condition Error," January 2009.

Document Control Desk Attachment II LTD 321 RC-15-0100 Page 7 of 11

5. CGE-10-29, "BELOCA Summary Report," November 2010.

6. LTR-LIS-12-372, "V. C. Summer, 10 CFR 50.46 Notification and Reporting for Fuel Pellet Thermal Conductivity Degradation and Peaking Factor Burndown," September 20, 2012.

7. LTR-LIS-13-353, "V. C. Summer 10 CFR 50.46 Report for Revised Heat Transfer Multiplier Distributions," July 2013.

8. LTR-LIS-13-476, "V. C. Summer 10 CFR 50.46 Report for Changes to Grid Blockage Ratio and Porosity," October 2013.

9. LTR-LIS-14-37, "V. C. Summer 10 CFR 50.46 Report for the HOTSPOT Burst Strain Error Correction," January 2014.

Notes:

(a) This evaluation credits peaking factor burndown, see Reference 6.

(b) This input error was originally reported in Reference 4. That evaluation is superseded by the report in Reference 6.

Document Control Desk Attachment II LTD 321 RC-15-0100 Page 8 of 11 Westinghouse LOCA Peak Clad Temperature Summary for Best Estimate Large Break Plant Name: V. C. Summer Utility Name: South Carolina Electric & Gas Revision Date: 2/10/2015 Reflood 2 Analysis Information EM: CQD (1996) Analysis Date: 2/3/2003 Limiting Break Size: Guillotine FQ: 2.5 FdH: 1.7 Fuel: Vantage + SGTP (%): 10 Notes: Delta 75 Replacement Steam Generator Uprate Core Power 2900 MWt Clad Temp (°F) Ref. Notes LICENSING BASIS Analysis-Of-Record PCT 1988 1 PCT ASSESSMENTS (Delta PCT)

A. PRIOR ECCS MODEL ASSESSMENTS

1. Backfit Through 2001 Reporting Year 0 2

2. Revised Blowdown Heatup Uncertainty Distribution 5 3

3. PAD 4.0 Implementation -118 6

4. Evaluation of Fuel Pellet Thermal Conductivity 123 6 (a)

Degradation and Peaking Factor Burndown

5. Transverse Momentum Cells for Zero Cross-flow 0 6 (b)

Boundary Condition Error

6. Revised Heat Transfer Multiplier Distributions -35 7

7. Changes to Grid Blockage Ratio and Porosity 24 8

8. Error in Burst Strain Application 0 9 B. PLANNED PLANT MODIFICATION EVALUATIONS

1. Fan Cooler Performance Increase 2 2

2. Upflow Conversion Evaluation -29 4

3. Additional Heat Sinks and Increased Spray Flow Rate 1 5 C. 2014 ECCS MODEL ASSESSMENTS

1. None 0 D. OTHER

1. None 0 LICENSING BASIS PCT + PCT ASSESSMENTS PC T= 1961 References

1. WCAP-1 6043, "Best Estimate Analysis of the Large Break Loss of Coolant Accident for the Virgil C. Summer Nuclear Station," June 2003.

2. CGE-03-12, "10 CFR 50.46 Annual Notification and Reporting for 2002," March 2003.

3. CGE-05-20, "10 CFR 50.46 Annual Notification and Reporting for 2004," April 2005.

4. LTR-LIS-08-578, Revision 2, "10 CFR 50.46 Reports for the V. C. Summer (CGE)

Upflow Conversion Large Break LOCA Evaluation and Assessment of Transverse Momentum Cells with a Zero Cross-flow Boundary Condition Error," January 2009.

5. CGE-10-29, "BELOCA Summary Report," November 2010.

6. LTR-LIS-12-372, "V. C. Summer, 10 CFR 50.46 Notification and Reporting for Fuel

Document Control Desk Attachment II LTD 321 RC-l 5-0100 Page 9 of 11 Pellet Thermal Conductivity Degradation and Peaking Factor Burndown," September 20, 2012.

7. LTR-LIS-1 3-353, "V. C. Summer 10 CFR 50.46 Report for Revised Heat Transfer Multiplier Distributions," July 2013.

8. LTR-LIS-13-476, "V. C. Summer 10 CFR 50.46 Report for Changes to Grid Blockage Ratio and Porosity," October 2013.

9. LTR-LIS-14-37, "V. C. Summer 10 CFR 50.46 Report for the HOTSPOT Burst Strain Error Correction," January 2014.

Notes:

(a) This evaluation credits peaking factor burndown, see Reference 6.

(b) This input error was originally reported in Reference 4. That evaluation is superseded by the report in Reference 6.

Document Control Desk Attachment II LTD 321 RC-15-0100 Page 10 of 11 Westinghouse LOCA Peak Clad Temperature Summary for Appendix K Small Break Plant Name: V. C. Summer Utility Name: South Carolina Electric & Gas Revision Date: 2/4/2015 Analysis Information EM: NOTRUMP Analysis Date: 9/12/2006 Limiting Break Size: 3 Inch FQ: 2.45 FdH: 1.62 Fuel: Vantage + SGTP(%): 10 Notes:

Clad Temp (°F) Ref. Notes LICENSING BASIS Analysis-Of-Record PCT 1775 9 (a)

PCT ASSESSMENTS (Delta PCT)

A. PRIOR ECCS MODEL ASSESSMENTS

1. None 0 B. PLANNED PLANT MODIFICATION EVALUATIONS

1. Upflow Conversion 148 10,11 C. 2014 ECCS MODEL ASSESSMENTS

1. None 0 D. OTHER

1. None 0 LICENSING BASIS PCT + PCT ASSESSMENTS PCT= 1923 References

1. CGE-94-205, "South Carolina Electric and Gas Company, Virgil C. Summer Station, 10 CFR 50.46 Notification and Reporting Information," February 8, 1994.

2. CGE-94-228, "South Carolina Electric and Gas Company, Virgil C. Summer Station, SBLOCTA Axial Nodalization," October 27, 1994.

3. CGE-95-201, "South Carolina Electric and Gas Company, Virgil C. Summer Station, 10 CFR 50.46 Notification and Reporting Information," February 3, 1995.

4. CGE-96-202, "South Carolina Electric and Gas Company, Virgil C. Summer Station, 10 CFR 50.46 Annual Notification and Reporting," February 9, 1996.

5. CGE-96-213, "South Carolina Electric and Gas Company, Virgil C. Summer Station, 10 CFR 50.46 Small Break LOCA Notification and Reporting," July 8, 1996.

6. CGE-00-044, "South Carolina Electric and Gas Company, Virgil C. Summer Nuclear Station, 10 CFR 50.46 Appendix K (BART / BASH / NOTRUMP) Evaluation Model, Mid-Year Notification and Reporting for 2000," June 30, 2000.

7. CGE-03-80, "10 CFR 50.46 Mid-Year Notification and Reporting for 2003,"

January 2004.

8. LTR-LIS-06-344, "Transmittal of Updated V. C. Summer SBLOCA PCT Rackup Sheets," November 2006.

9. LTR-LIS-06-662, Transmittal of V. C. Summer SBLOCTA PCT Rackup Sheets for HHSI Throttle Valve Replacement," November 2006.

10. WCAP-1 6980-P, Revision 1, "Reactor Internals Upflow Conversion Program

Document Control Desk Attachment II LTD 321 RC-1 5-0100 Page 11 of 11 Engineering Report V. C. Summer Nuclear Station Unit 1," December 2008.

11. LTR-LIS-09-18, "10 CFR 50.46 Report for the V. C. Summer (CGE) Upflow Conversion Program Small Break LOCA Evaluation," January 2009.

Notes:

(a) The Rebaseline Analysis includes the impacts of the following model assessments:

1-LUCIFER Error Corrections (Ref. 1) 2-Effect of SI in Broken Loop (Ref. 1) 3-Effect of Improved Condensation Model (Ref. 1) 4-Axial Nodalization, RIP Model Revision and SBLOCTA Error Corrections Analysis (Ref. 2) 5-Boiling Heat Transfer Error (Ref. 3) 6-Steam Line Isolation Logic Error (Ref. 3) 7-NOTRUMP Specific Enthalpy Error (Ref. 4) 8-SALIBRARY Double Precision Error (Ref. 4) 9-SBLOCTA Fuel Rod Initialization Error (Ref. 5) 10-NOTRUMP Mixture Level Tracking / Region Depletion Errors (Ref. 6) 11-NOTRUMP Bubble Rise / Drift Flux Model Inconsistency Corrections (Ref. 7) 12-Refined Break Spectrum (Ref. 8) 13-High head safety injection (HHSI) flow increase (Ref. 9)