VIRGINIA ELECTRIC AND POWER COMPANY

RICHMOND, VIRGINIA 23261

January 23, 201410 CFR 50.90

U. S. Nuclear Regulatory Commission Serial No. 13-145AATTN: Document Control Desk NL&OS/GDM R2Washington, D. C. 20555 Docket Nos. 50-280/281

50-338/339License Nos. DPR-32/37

NPF-4/7

VIRGINIA ELECTRIC AND POWER COMPANYSURRY POWER STATION UNITS I AND 2NORTH ANNA POWER STATION UNITS 1 AND 2PROPOSED LICENSE AMENDMENT REQUEST (LAR)ADDITION OF AN ANALYTICAL METHODOLOGY TO THE NORTH ANNA ANDSURRY CORE OPERATING LIMITS REPORTS (COLRS) AND AN INCREASE TOTHE SURRY MINIMUM TEMPERATURE FOR CRITICALITYRESPONSE TO NRC REQUEST FOR ADDITIONAL INFORMATION

By letter dated June 26, 2013 (Serial No. 13-145), Virginia Electric and Power Company(Dominion) requested amendments, in the form of changes to the TechnicalSpecifications (TS) to Facility Operating License Numbers NPF-4 and NPF-7 for NorthAnna Power Station Units 1 and 2, and the Technical Specifications (TS) to FacilityOperating License Numbers DPR-32 and DPR-37 for Surry Power StationUnits 1 and 2, respectively. The proposed LAR requests approval of the followingitems: 1) generic application of Appendix D, "Qualification of the ABB-NV and WLOPCritical Heat Flux (CHF) Correlations in the Dominion VIPRE-D Computer Code," toFleet Report DOM-NAF-2-A, "Reactor Core Thermal-Hydraulics Using the VIPRE-DComputer Code," 2) the plant specific application of Appendix D to DOM-NAF-2-A toNorth Anna and Surry Power Stations (in accordance with Section 2.1 of DOM-NAF-2-A), and 3) an increase in the Surry Power Station TS Minimum Temperature forCriticality. The plant specific application of Appendix D to DOM-NAF-2-A requires theinclusion of the appendix to the TS list of references for determining core operatinglimits (i.e., the TS list of COLR references).

In an email dated December 24, 2013, the NRC provided a request for additionalinformation (RAI) in support of their technical review. Dominion's response to the RAI isprovided in the attachment to this letter.

The information provided in this letter does not affect the conclusion of the significanthazards consideration or the environmental assessment discussion contained in theDominion letter dated June 26, 2013.

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If you have any questions or require additional information,Mr. Thomas Shaub at (804) 273-2763.

please contact

Sincerely,

Mark D. SartainVice President - Nuclear Engineering and Development

COMMONWEALTH OF VIRGINIA

COUNTY OF HENRICO

)))

The foregoing document was acknowledged before me, in and for the County andCommonwealth aforesaid, today by Mark D. Sartain, who is Vice President of NuclearEngineering and Development, of Virginia Electric and Power Company. He hasaffirmed before me that he is duly authorized to execute and file the foregoing documentin behalf of that Company, and that the statements in the document are true to the bestof his knowledge and belief.

Acknowledged before me this ,j :-day of

My Commission Expires: 3/ 2C

2014.

Notary PublicCommonwealth of Virginia

140542My Commission Expires May 31, 2014 Notary Public

Commitments made in this letter: None

Attachment: Response to NRC Request for Additional Information

Serial No.13-145ADocket Nos. 50-280/281 and 50-338/339

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cc: U.S. Nuclear Regulatory CommissionRegion IIMarquis One Tower245 Peachtree Center Avenue, NE Suite 1200Atlanta, Georgia 30303-1257

NRC Senior Resident InspectorNorth Anna Power Station

NRC Senior Resident InspectorSurry Power Station

Ms. K. R. Cotton GrossNRC Project ManagerU. S. Nuclear Regulatory CommissionOne White Flint NorthMail Stop 08 G-9A11555 Rockville PikeRockville, Maryland 20852-2738

Dr. V. SreenivasNRC Project ManagerU. S. Nuclear Regulatory CommissionOne White Flint NorthMail Stop 08 G-9A11555 Rockville PikeRockville, Maryland 20852-2738

Mr. J. E. Reasor, Jr.Old Dominion Electric CooperativeInnsbrook Corporate Center, Suite 3004201 Dominion Blvd.Glen Allen, Virginia 23060

State Health CommissionerVirginia Department of HealthJames Madison Building - 7 th Floor109 Governor StreetRoom 730Richmond, Virginia 23219

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RESPONSE TO NRC REQUEST FOR ADDITIONAL INFORMATION

Virginia Electric and Power Company(Dominion)

Surry Power Station Units I and 2North Anna Power Station Units 1 and 2

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RESPONSE TO NRC REQUEST FOR ADDITIONAL INFORMATION

By letter dated June 26, 2013, Virginia Electric and Power Company (Dominion),requested amendments to the Renewed Facility Operating License (FOL) NumbersNPF-4 and NPF-7 for North Anna Power Station (North Anna) Units 1 and 2,respectively, and the Technical Specifications (TS) to FOL Numbers DPR-32 andDPR-37 for Surry Power Station (Surry) Units 1 and 2, respectively. The proposedlicense amendment request (LAR) requested the approval of the following items:(1) generic application of Appendix D, "Qualification of the ABB-NV and WLOP CriticalHeat Flux (CHF) Correlations in the Dominion VIPRE-D Computer Code," to FleetReport DOM-NAF-2-A, "Reactor Core Thermal-Hydraulics Using the VIPRE-DComputer Code," (2) the plant specific application of Appendix D to DOM-NAF-2-A toNorth Anna and Surry (in accordance with Section 2.1 of DOM-NAF-2-A), and (3) anincrease in the Surry TS minimum temperature for criticality.

The NRC technical review staff has reviewed the LAR and determined that additionalinformation is needed to complete its evaluation. The NRC questions and theassociated Dominion responses are provided below.

RAI-I Attachment 1. Sections 1. 2.3. and 5.1.2

(a) Describe the impact of increasing the Minimum Temperature for Criticality for SurryUnits on maintaining the shutdown margin during the startup of the units.

Response

Shutdown margin (SDM) is defined in Surry TS as the amount by which the reactor corewould be subcritical at hot shutdown (average temperature -> 547°F) conditions. Bydefinition, changing the minimum temperature for criticality (from 5220F to 5380F) doesnot technically affect SDM. The impact of the change is to the analytical calculation ofSDM. As specified in internal analysis guidance documents for Dominion's ReloadSafety Analysis Checklist (RSAC) process, the calculation of SDM conservativelyaddresses parameters which may produce conditions outside of the definition, such asinstrument uncertainty and minimum temperature for criticality. An increase in theminimum temperature for criticality reduces the temperature range to be bounded inDominion's RSAC process, resulting in an increase in the minimum available shutdownmargin for two otherwise identical cores. The process of unit startup is unaffected bythe increase in the minimum temperature for criticality. The increased minimumtemperature for criticality TS limit will be reflected in the applicable station procedures.

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(b) It is stated that "the increased Minimum Temperature for Criticality will continue to beverified against the assumptions in the safety analyses on a reload basis and doesnot impact the NRC approved analytical methods used to determine the coreoperating limits such as the MTC. Describe the processes/procedures in place toachieve this objective.

Response

The minimum temperature for criticality is an input to various RSAC calculations. TheRSAC calculations are performed each cycle per Dominion's NRC-approved ReloadNuclear Design Methodology (Reference 1.1). The proposed value will be incorporatedinto the appropriate Dominion internal analysis guidance documents that include theminimum temperature for criticality, such as Moderator Temperature Coefficient (MTC)calculations. Increasing Surry's minimum temperature for criticality will result inrequired updates to affected Dominion internal analysis guidance documents to reflectthe new minimum temperature for criticality.

(c) Explain how the increase in TS Minimum Temperature for Criticality coupled withintroduction of the W-3 alternate CHF correlations at Surry units will provide(1) increased flexibility in loading pattern development as well as improved margins,and (2) improved predictive capabilities in determining the thermal-hydraulicperformance at Surry, as claimed in Section 2.3 of Attachment I of the LAR.

Response

The improved predictive capabilities of the W-3 Alternate CHF correlations provideDominion additional thermal margin as shown in the response to RAls 3(b) and 4 below.This additional margin removes the reload core design constraint imposed by the MainSteam Line Break (MSLB) and Rod Withdrawal from Subcritical (RWSC) accidentanalyses, and reload axial power shape departure from nucleate boiling (DNB) analysis.The increase in the minimum temperature for criticality results in more margin to themost positive MTC limit, which allows consideration of loading patterns with slightlyhigher soluble boron. Together these changes provide flexibility to consider moreoptimized loading patterns.

References

1.1. Topical Report, VEP-FRD-42-A, Rev. 2.1-A, "Reload Nuclear DesignMethodology," August 2003.

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RAI-2 Attachment I Section 4.2

Please provide details of how the retained DNBR margin is used to offset generic DNBRpenalty for rod bow. Explain how the rod bow penalty is quantified in the analysis.

Response

Retained DNB ratio (DNBR) margin is quantified as the percent difference between theSafety Analysis Limit (SAL) and Deterministic Design Limit (DDL) as discussed inAttachment 1, Sections 4.2 and 4.3 of Reference 2.1 for North Anna and Surry,respectively. The DDLs are developed using the population statistics of the appropriateCHF correlation test databases and are set such that the probability of avoiding DNBwill be at least 95% at a 95% confidence level (Attachment 6, Section D.6 of Reference2.1 for ABB-NV and WLOP). Therefore, the DDLs are fixed and any changes to theirvalues would require NRC review and approval. Dominion evaluates the Updated FinalSafety Analysis Report (UFSAR) Chapter 14 and 15 safety analyses for Surry and NorthAnna, respectively, against the self-imposed SAL, which is greater than the DDL. Thedifference between the DDL and SAL provides DNB margin to offset the effect of rodbow and other DNB penalties, which are most effectively addressed on a generic basis.The SALs for DNB analyses may be changed without prior NRC review and approvalprovided the changes meet the criteria established in Reference 2.2.

The method for calculating the rod bow penalty and using retained DNBR margin tooffset the rod bow penalty is consistent with the North Anna and Surry licensing basis.Dominion calculates the generic DNBR penalty for rod bow using the NRC approvedmethodology described in WCAP-8691, Revision 1 (References 2.3 and 2.4). Specificdiscussion can be found on the rod bow methodology and its application to retainedDNBR margin in the North Anna UFSAR, Sections 4.4.1.1 and 4.4.2.3.4.2 and the SurryUFSAR, Section 3.4.3.5.

References

2.1. Letter from David A. Heacock (Dominion) to Document Control Desk (NRC),"Virginia Electric and Power Company, Surry Power Station Units 1 and 2, NorthAnna Power Station Units 1 and 2, Proposed License Amendment Request (LAR),Addition of an Analytical Methodology to the North Anna and Surry Core OperatingLimits Reports (COLRS) and an Increase to the Surry Minimum Temperature forCriticality," Serial No. 13-145, ADAMS Accession No. ML13179A014, June 26,2013.

2.2. Technical Report, NEI 96-07, Revision 1, "Guidelines for 10 CFR 50.59Implementation," Nuclear Energy Institute, November 2000.

2.3. Topical Report, WCAP-8691-P-A, Revision 1, "Fuel Rod Bow Evaluation," July1979.

2.4. Letter from C. 0. Thomas (NRC) to E. P. Rahe, Jr. (Westinghouse), "Acceptancefor Referencing of Licensing Topical Report WCAP-8691(P)ANCAP-8692(NP),"December 29, 1982.

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RAI-3 Attachment 1, Sections 4.2 and 4.3

It is stated that WLOP CHF correlation is to be applied when the conditions occuroutside of the range of applicability of the primary CHF correlation, say, for low pressureor low flow conditions. Please provide response to the questions below:

(a) Provide details of the correlation(s) currently used to analyze low pressure or lowflow transients at Surry and North Anna Units.

Response

As described in Attachment 1, Section 2.1 of Reference 3.1, the WLOP CHF correlationis a replacement for the W-3 CHF correlation at low pressure and low flow operatingconditions. The WLOP CHF correlation will replace the W-3 correlation as applied tothe MSLB event because of the lower pressures encountered.

Dominion currently uses the W-3 correlation when determining the thermal-hydraulicperformance of Westinghouse fuel products within North Anna and Surry's cores whenthe conditions occur outside of the range of applicability of the primary CHF correlation,such as at low pressure and low flow conditions. W-3 is one of the CHF correlationscontained in the USNRC approved generic version of VIPRE-01 (References 3.2and 3.3). Appendix B, Section B.2 and Appendix C, Section C.2 of DOM-NAF-2-A(Reference 3.4) describe the approved application of W-3 with the WRB-1 and WRB-2MCHF correlations in VIPRE-D, respectively. DOM-NAF-2-A, Appendix B has beenincorporated into the Surry Core Operating Limits Report (COLR) list of approvedmethodologies and DOM-NAF-2-A, Appendix C has been incorporated into the NorthAnna COLR list of approved methodologies.

(b) What is the impact/advantage on DNBR and thermal performance margins whenSurry and North Anna transition to WLOP CHF correlation to analyze low pressureor low flow transients.

Response

The advantage to DNBR and thermal performance margins with a North Anna andSurry transition to the WLOP CHF Correlation can be illustrated by the increase inretained DNBR margin. Retained DNBR margin is discussed in detail in the responseto RAI 2. Currently, the W-3 CHF Correlation provides 9.7% retained DNBR margin atand above 1000 psia and 9.9% retained DNBR margin below 1000 psia for both Surryand North Anna (Attachment 4, Section 4.3 of References 3.5 and 3.6). The resultingavailable retained DNBR margin with use of WLOP in VIPRE-D will yield 12.8% retainedDNBR margin for Surry (Attachment 1, Section 4.3 of Reference 3.1) and 21.2%retained DNBR margin for North Anna (Attachment 1, Section 4.2 of Reference 3.1).

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North Anna and Surry have different SALs for the WLOP CHF correlation due to theDNBR results for each site's specific MSLB transient analysis. The DNBR results fromthe site-specific transient evaluation set an upper bound on the allowed SAL.Dominion's response to RAI 4 provides a sample minimum DNBR (MDNBR)comparison between W-3 and WLOP for a representative MSLB event.

References

3.1. Letter from David A. Heacock (Dominion) to Document Control Desk (NRC),"Virginia Electric and Power Company, Surry Power Station Units 1 and 2, NorthAnna Power Station Units 1 and 2, Proposed License Amendment Request (LAR),Addition of an Analytical Methodology to the North Anna and Surry Core OperatingLimits Reports (COLRS) and an Increase to the Surry Minimum Temperature forCriticality," Serial No. 13-145, ADAMS Accession No. ML042800118, datedJune 26, 2013.

3.2. Letter from C. E. Rossi (NRC) to J. A. Blaisdell (UGRA Executive Committee),"Acceptance for Referencing of Licensing Topical Report, EPRI NP-2511-CCM,'VIPRE-01: A Thermal-Hydraulic Analysis Code for Reactor Cores,' Volumes 1, 2,3 and 4," dated May 1, 1986.

3.3. Letter from A. C. Thadani (NRC) to Y. Y. Yung (VIPRE-01 Maintenance Group),"Acceptance for Referencing of the Modified Licensing Topical Report, EPRI NP-2511-CCM, Revision 3, 'VIPRE-01: A Thermal Hydraulic Analysis Code forReactor Cores,' (TAC No. M79498)," dated October 30, 1993.

3.4. Fleet Report, DOM-NAF-2-A, Rev. 0.2-P-A, including Appendixes A, B and C,"Reactor Core Thermal-Hydraulics Using the VIPRE-D Computer Code," ADAMSAccession No. ML102390419, August 2010.

3.5. Letter from J. Alan Price (Dominion) to Document Control Desk (NRC), "VirginiaElectric and Power Company Surry Power Station Units 1 and 2 Proposed LicenseAmendment Request Relocation of Core Operating Limits to the Core OperatingLimits Report (COLR) and Addition of COLR References," Serial No. 09-581,ADAMS Accession No. ML092960616, October 16, 2009.

3.6. Letter from J. Alan Price (Dominion) to Document Control Desk (NRC), "VirginiaElectric and Power Company North Anna Power Station Units 1 and 2 ProposedLicense Amendment Request (LAR) Addition of Analytical Methodology to COLR,"Serial No. 10-404, ADAMS Accession No. ML102020165, July 19, 2010.

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RAI-4 Attachment 1. Sections 4.2 and 4.3

Please show with typical calculations in support of your statement that there are nochanges to the OTAT, OPA T, FAH, reactor protection system, or the Reactor CoreSafety Limits (RCSLs) due to the implementation of the W-3 alternate CHF correlationsat North Anna and Surry units.

Response

The OTAT, OPAT and f(AI) reactor protection functions are established to ensurebounding protection for the core thermal limits. The response below demonstrates thatthe ABB-NV and WLOP CHF correlations provide improved calculated thermalperformance over the W-3 CHF correlation, and that the current reactor protectionsetpoints would continue to provide bounding protection if analyzed with the alternateCHF correlations. The RCSLs are unaffected by the W-3 Alternate CHF correlations asthe RCSLs fall within the NRC-approved range of applicability of the primary CHFcorrelation (e.g. WRB-1 or WRB-2M).

Sections 4.2 and 4.3 of Reference 4.1 describe how the W-3 Alternate CHF correlationswill be applied at North Anna and Surry and the impact of the W-3 Alternate correlationson the Reactor Protection System (RPS) and UFSAR transients. The ABB-NV CHFcorrelation is to be applied when the limiting location of DNBR occurs below the firstmixing vane grid (MVG) and the WLOP CHF correlation is to be applied when theMDNBR condition occurs outside of the range of applicability of the primary CHFcorrelation. Specifically, the ABB-NV CHF correlation is employed in the presence of ahighly bottom skewed power shape (when the limiting MDNBR occurs below the firstMVG, e.g., RWSC) and the WLOP CHF correlation is employed at low pressure and lowflow conditions (e.g., MSLB).

Dominion performed statepoint calculations across the licensing basis range of the W-3CHF correlation at North Anna and Surry to quantify the DNB margins generated ateach statepoint with use of the W-3 Alternate CHF correlations. The current licensingbasis range of W-3 at North Anna and Surry includes the RWSC event (ABB-NVlimiting), MSLB event (WLOP limiting), and the statepoints used in the development ofreactor protection (RP) setpoints which result in a MDNBR below the first MVG(ABB-NV limiting). Table 4-1 lists the MDNBR results for a selection of North Anna andSurry UFSAR and RP statepoints evaluated to quantify the thermal-hydraulicperformance margin provided with use of the alternate CHF correlations. The differencebetween the VIPRE-D result and the DDL is provided in Table 4-1 as the margin to theDDL:

/M oNBR - DL)Margin to the DDL [%] =, DDL ) 100

The appropriate DDLs for comparison are contained within the table footnotes. Theresults of the calculations demonstrate that the minimum DNBR values are equal to or

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greater than the appropriate North Anna or Surry DNBR DDLs and SALs for the RCSLs,the OTAT, OPAT, and f(AI) reactor trip setpoints, as well as the applicable UFSARevents (i.e., RWSC and MSLB). Thus, the current RPS setpoints and RCSLs wouldcontinue to provide bounding protection of the core thermal limits when analyzed withthe ABB-NV and WLOP CHF correlations in lieu of the W-3 CHF correlation.

Table 4-1: Sample Statepoints Used for the Development of North Anna and SurryDNBR Limits for the W-3 Alternate CHF Correlations

Power W-3 ABB-NVIWLOPCase psure [% of Rated Margin to Mar

[psial Thermal Power] DDL1 [%] MDNBR DDL" to

ABB-NV - RP1 2400 100 1.44 10.77 1.85 62.28ABB-NV- RP2 2250 100 1.44 10.77 1.84 61.40ABB-NV- RP3 2000 100 1.44 10.77 1.80 57.89ABB-NV - RP4 1860 100 1.44 10.77 1.77 55.26ABB-NV - RP5 2250 90 1.44 10.77 1.88 64.91ABB-NV - RP6 2250 118 1.44 10.77 1.76 54.39

ABB-NV - RWSC 2320 35.4 2.01 54.62 2.34 105.26WLOP - MSLB 869.8 23.7 2.34 61.38 2.01 64.75

1. VIPRE-D/V-3 DDL (2:1000 psia): 1.30; VIPRE-DAW-3 DDL (<1000 psia): 1.45 (References 4.2 and 4.3)2. VIPRE-D/ABB-NV DDL: 1.14; VIPRE-DNVLOP DDL: 1.22 (Reference 4.1)

References

4.1. Letter from David A. Heacock (Dominion) to Document Control Desk (NRC),"Virginia Electric and Power Company, Surry Power Station Units 1 and 2, NorthAnna Power Station Units 1 and 2, Proposed License Amendment Request (LAR),Addition of an Analytical Methodology to the North Anna and Surry Core OperatingLimits Reports (COLRS) and an Increase to the Surry Minimum Temperature forCriticality," Serial No. 13-145, ADAMS Accession No. ML042800118, dated June26, 2013.

4.2. Letter from J. Alan Price (Dominion) to Document Control Desk (NRC), "VirginiaElectric and Power Company Surry Power Station Units 1 and 2 Proposed LicenseAmendment Request Relocation of Core Operating Limits to the Core OperatingLimits Report (COLR) and Addition of COLR References," Serial No. 09-581,ADAMS Accession No. ML092960616, October 16, 2009.

4.3. Letter from J. Alan Price (Dominion) to Document Control Desk (NRC), "VirginiaElectric and Power Company North Anna Power Station Units 1 and 2 ProposedLicense Amendment Request (LAR) Addition of Analytical Methodology to COLR,"Serial No. 10-404, ADAMS Accession No. ML102020165, July 19, 2010.

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RAI-5

Limitations and Conditions Number 3 for the Safety Evaluation Report for WCAP-14565-P-A stipulates that Selection of the appropriate DNB correlation, DNBR limit,engineering hot channel factors for enthalpy rise, and other fuel dependent parameterswill be justified for each application of each correlation on a plant specific basis.This is also listed as Number 7 of Section 7.0 Conclusions of Topical ReportWCAP- 14565-P-A.

Please describe how the Limitations and Conditions number 3 is justified/implementedin connection with the use of ABB-NV and WLOP correlations in North Anna and Surryunits.

Response

Dominion performs DNBR analysis of the North Anna and Surry Units in accordancewith the approved thermal-hydraulic methodology outlined in DOM-NAF-2-A(Reference 5.1). Consistent with the requirements of DOM-NAF-2-A, qualification of theABB-NV and WLOP CHF correlations has been performed and the results have beendocumented in Appendix D to DOM-NAF-2-A (Reference 5.2, Attachment 6).Furthermore, use of the ABB-NV and WLOP CHF correlations in licensing DNBRcalculations for the North Anna and Surry Units is governed by DOM-NAF-2-A.

Section 2.2 of Reference 5.1 provides the conditions under which Dominion applies theVIPRE-D computer code to meet the USNRC's requirements listed in the VIPRE-01Safety Evaluation Report (SER) (References 5.3 and 5.4) which satisfy Limitation andCondition Number 3 of the WCAP-14565-P-A, Addendum 2-P-A SER (Reference 5.5).The specific VIPRE-D conditions which comply with Limitation and Condition Number 3of Reference 5.5 are provided below:

Condition 2 of Section 2.2 "Compliance with VIPRE-01 SER" of DOM-NAF-2-Astates: "VIPRE-D analyses will only use DNB correlations that have beenreviewed and approved by the USNRC. The VIPRE-D DNBR calculations will bewithin the USNRC approved parameter ranges of the DNB correlations, includingfuel assembly geometry and grid spacers. The correlation DNBR design limitswill be derived or verified using fluid conditions predicted by the VIPRE-D code.Each DNB correlation will be qualified or verified in appendixes to this report."

Section B.2 of DOM-NAF-2-A, Appendix B and Section C.2 of DOM-NAF-2-A,Appendix C state the range of applicability of the W-3 CHF correlation with use ofthe WRB-1 and WRB-2M CHF correlations, respectively. The ABB-NV andWLOP CHF correlations are used as alternatives to the W-3 correlation whereW-3 is applicable. The applicability of the W-3 Alternate CHF correlations isprovided in Section D.2 of DOM-NAF-2-A, Appendix D: "The ABB-NV and WLOPCHF correlations are applicable for use in the thermal-hydraulic evaluation of

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14x14 fuel products with a rod outside diameter (OD) of 0.400 or 0.422 inches;15x15 fuel products with a rod OD of 0.422 inches; 16x16 fuel products with arod OD of 0.360 or 0.374 inches; and 17x17 fuel products with a rod OD of 0.360or 0.374 inches (Reference D4)." Therefore, condition 2 of DOM-NAF-2-A,Section 2.2 with the approved CHF correlation applicability ranges discussedabove satisfy the "selection of the appropriate DNB correlation" and "DNBR limit"portion of Limitation and Condition Number 3 of the WCAP-14565-P-A,Addendum 2-P-A SER.

Condition 3 of Section 2.2, "Compliance with VIPRE-01 SER" of DOM-NAF-2-Astates: "This report provides the necessary documentation to describe theintended uses of VIPRE-D for PWR licensing applications. The report providesjustification for Dominion's specific modeling assumptions, including the choice oftwo-phase flow models and correlations, heat transfer correlations and turbulentmixing models. Dominion only applies models and correlations already existing inVIPRE-01 and previously approved by the USNRC."

The engineering enthalpy-rise hot channel factor is obtained from the fuel vendorfor a given fuel type and is independent of the DNB correlation. The hot channelfactor is accounted for in licensing DNBR calculations as described inSection 4.10 of DOM-NAF-2-A (Reference 5.1). The selection of other fueldependent parameters and their use in licensing DNBR calculations are outlinedin Section 4.0 of DOM-NAF-2-A. As noted above, Dominion performs DNBRanalysis of the North Anna and Surry Units in accordance with the approvedthermal-hydraulic methodology outlined in DOM-NAF-2-A. Therefore, condition 3of DOM-NAF-2-A, Section 2.2 with the approved VIPRE-D modeling criteriadescribed in Section 4.0 of DOM-NAF-2-A satisfy the selection of the"appropriate engineering hot channel factors for enthalpy rise" and "other fueldependent parameters" portion of Limitation and Condition Number 3 of theWCAP-14565-P-A, Addendum 2-P-A SER.

References

5.1. Fleet Report, DOM-NAF-2-A, Rev. 0.2-P-A, including Appendixes A, B and C,"Reactor Core Thermal-Hydraulics Using the VIPRE-D Computer Code," ADAMSAccession No. ML1 02390419, August 2010.

5.2. Letter from David A. Heacock (Dominion) to Document Control Desk (NRC),"Virginia Electric and Power Company, Surry Power Station Units 1 and 2, NorthAnna Power Station Units 1 and 2, Proposed License Amendment Request (LAR),Addition of an Analytical Methodology to the North Anna and Surry Core OperatingLimits Reports (COLRS) and an Increase to the Surry Minimum Temperature forCriticality," Serial No. 13-145, ADAMS Accession No. ML042800118, dated June26, 2013.

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5.3. Letter from C. E. Rossi (NRC) to J. A. Blaisdell (UGRA Executive Committee),"Acceptance for Referencing of Licensing Topical Report, EPRI NP-2511-CCM,'VIPRE-01: A Thermal-Hydraulic Analysis Code for Reactor Cores,' Volumes 1, 2,3 and 4," May 1, 1986.

5.4. Letter from A. C. Thadani (NRC) to Y. Y. Yung (VIPRE-01 Maintenance Group),"Acceptance for Referencing of the Modified Licensing Topical Report, EPRI NP-2511-CCM, Revision 3, 'VIPRE-01: A Thermal Hydraulic Analysis Code forReactor Cores,' (TAC No. M79498)," October 30, 1993.

5.5. Letter from Ho K. Nieh (NRC) to James A. Gresham (Westinghouse), "Final SafetyEvaluation for Westinghouse Electric Company (Westinghouse) Topical Report(TR) WCAP-14565-P, Addendum 2, Revision 0, 'Addendum 2 to WCAP-14565-P-A, Extended Application of ABB-NV Correlation and Modified ABB-NV CorrelationWLOP [Westinghouse Low Pressure] for PWR [Pressurized Water Reactor] LowPressure Applications' (TAC No. MD3184)," ADAMS Accession No.ML080360381, February 14, 2008.

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