Text

North Anna, Unit 2, Status of Required Actions for EA-12-049 Issuance of Order to Modify Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events
	ML14349A320
Person / Time
Site:	North Anna
Issue date:	12/08/2014
From:	Mark D. Sartain; Virginia Electric & Power Co (VEPCO)
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	14-394A, EA-12-049
	Download: ML14349A320 (63)
	v • d • e

VIRGINIA ELECTRIC AND POWER COMPANYRICHMOND, VIRGINIA 23261December 8, 2014U. S. Nuclear Regulatory Commission Serial No.: 14-394AAttention:

Document Control Desk NLOS/ETS:

R1Washington, DC 20555-0001 Docket No.: 50-339License No.: NPF-7VIRGINIA ELECTRIC AND POWER COMPANYNORTH ANNA POWER STATION UNIT 2STATUS OF REQUIRED ACTIONS FOR EA-12-049 ISSUANCE OF ORDER TO MODIFY LICENSES WITH REGARD TO REQUIREMENTS FORMITIGATION STRATEGIES FOR BEYOND-DESIGN-BASIS EXTERNAL EVENTSOn March 28, 2012 the NRC issued EA-12-049, "Order to Modify Licenses with Regard toRequirements for Mitigation Strategies for Beyond-Design-Basis External Events" which required athree-phase approach for mitigating beyond-design-basis external events. The initial phase requiresthe use of installed equipment and resources to maintain or restore core cooling, containment andspent fuel pool (SFP) cooling capabilities.

The transition phase requires providing sufficient,

portable, onsite equipment and consumables to maintain or restore these functions until they can beaccomplished with resources brought from offsite.

The final phase requires obtaining sufficient offsite resources to sustain those functions indefinitely.

Condition C.3 of the Order required allLicensees to report to the Commission when full compliance with the requirements of the order isachieved.

This letter provides notification that Dominion has completed the requirements of EA-12-049 and isin full compliance with the Order for Unit 2. The attachments to this letter provide:

1) a summary ofhow the compliance requirements were met, and 2) the responses to the Open Items andConfirmatory Items from the Interim Staff Evaluation for EA-1 2-049 (ML1 3338A445) from the NRC,plus Dominion's responses to additional items identified in Attachments 4 and 5 of the North AnnaPower Station Onsite Audit Report dated September 24, 2014 (ML14259A458).

Should you have any questions or require additional information, please contact Margaret Earle at(804) 273-2768.

Respectfully, Mark Sartain I PUBLICVice President

-Nuclear Engineering Reg# 140542COMMONWEALTH OF VIRGINIACOUNTY OF HENRICOThe foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today by Mr. Mark D. Sartain, who is Vice President

-Nuclear Engineering, of Virginia Electric and Power Company.

He has affirmed before me that he is duly authorized to execute and file the foregoing document inbehalf of that company, and that the statements in the document are true to the best of his knowledge and belief.Acknowledged before me this day of be .C,6 , 2014.My Commission Expires:

/Notary Public 2 Serial No. 14-394ADocket No. 50-339Compliance with EA 12-049Page 2 of 2Order EA-12-049 Compliance Requirements SummaryResponse to ISE Open Items and ISE Confirmatory Items plus Additional ItemsIdentified in Attachments 4 and 5 of North Anna Power Station Units 1 and 2Onsite Audit Report, September 24, 2014Attachments:

1.2.Commitments contained in this letter:1. The Final Integrated Plan for North Anna Power Station, Units 1 and 2, will be submitted nolater than 60 days following the end of the North Anna Unit 1 second refueling outage following submittal of the OIP, currently scheduled for Spring 2015.2. When the new EPRI template for the RCS injection pumps is issued, the guidance in thetemplate will be reviewed and evaluated for incorporation in the periodic maintenance procedure.

cc: U.S. Nuclear Regulatory Commission

-Region IIMarquis One Tower245 Peachtree Center Avenue, NE Suite 1200Atlanta, GA 30303-1257 Dr. V. Sreenivas NRC Project Manager North AnnaU.S. Nuclear Regulatory Commission One White Flint NorthMail Stop 08 G-9A11555 Rockville PikeRockville, MD 20852-2738 Mrs. Lisa M. RegnerU.S. Nuclear Regulatory Commission One White Flint NorthMail Stop 011 F111555 Rockville PikeRockville, MD 20852-2738 Mr. Blake A. PurnellU.S. Nuclear Regulatory Commission One White Flint NorthMail Stop 012 D2011555 Rockville PikeRockville, MD 20852-2738 Mr. Steven R. JonesU.S. Nuclear Regulatory Commission One White Flint NorthMail Stop 010 Al11555 Rockville PikeRockville, MD 20852-2738 NRC Senior Resident Inspector North Anna Power Station Serial No. 14-394ADocket No. 50-339Compliance with EA 12-049Attachment 1Order EA-12-049 Compliance Requirements SummaryVirginia Electric and Power CompanyNorth Anna Power Station Unit 2 Serial No. 14-394ADocket No. 50-339Compliance with EA 12-049Attachment 1North Anna Power Station, Unit 2Order EA-12-049 Compliance Requirements SummaryNorth Anna Power Station developed an Overall Integrated Plan (OIP) (Reference 1),documenting diverse and flexible strategies (FLEX) in response to Order EA-12-049, "OrderModifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events,"

(Reference 2). The OIP for North Anna Power Station,Units 1 and 2 was submitted to the NRC on February 28, 2013 and was supplemented bySix-Month Status Reports (References 3, 4, and 5), in accordance with Order EA-12-049, along with an additional supplemental letter that was submitted on April 30, 2013(Reference 6).Full compliance of Order EA-12-049 was completed on October 8, 2014. This datecorresponds to the end of the second refueling outage after submittal of the OIP as requiredby Reference

2. The information provided herein documents full compliance withReference 2 for North Anna Power Station, Unit 2.Completion of the elements identified below for North Anna Power Station, Unit 2, as well asReferences 1, 3, 4, 5, and 6 document full compliance with Order EA-12-049 for North AnnaPower Station, Unit 2.NRC ISE AND AUDIT ITEMS -COMPLETEDuring the ongoing audit process (Reference 7), Dominion provided responses for thefollowing items for North Anna:" Interim Staff Evaluation (ISE) Open Items" ISE Confirmatory Items" Licensee Identified Open Items* Audit Questions

" Safety Evaluation Review ItemsThe "NRC North Anna Power Station, Units 1 and 2 -Report for the Onsite Audit Regarding Implementation of Mitigating Strategies and Reliable Spend Fuel Instrumentation Related toOrders EA-12-049 and EA-12-051" (Reference

8) delineated the items reviewed during theNorth Anna Power Station onsite audit. The report also identified additional audit items,specified as Safety Evaluation Review Items, which were added following the audit andrequired supplemental information to address these items.As requested by the NRC, Dominion's responses, or references to the source document forresponses, to the ISE Open Items or ISE Confirmatory Items (Reference 13), are provided inPage 1 of 5 Serial No. 14-394ADocket No. 50-339Compliance with EA 12-049Attachment 1Attachment 2 of this letter. Attachment 2 also provides the responses, or references to thesource document for responses, to Open or Pending Audit Questions and Licensee Identified Open Items related to Order EA-12-049 from Reference 7 and responses, or references tothe source document for responses to the Safety Evaluation Review Items associated withOrder EA-12-049.

It is Dominion's position that no further actions related to any of the aboveitems are required.

MILESTONE SCHEDULE

-ITEMS COMPLETEUnit 2 Milestone Completion DateSubmit Integrated Plan February 2013Develop Strategies October 2013Develop Modifications July 2014Implement Unit 2 Modifications October 2014Develop Training Plan April 2014Implement Training September 2014Issue FSGs and Associated Procedure Revisions September 2014Develop Strategies/Contract with NSRC August 2014Purchase Equipment February 2014Receive Equipment August 2014Validation Walk-Throughs or Demonstrations of FLEX August 2014Strategies and Procedures Create Maintenance Strategies August 2014Unit 2 Outage Implementation October 2014STRATEGIES

-COMPLETEStrategy related Open Items, Confirmatory Items, Audit Questions or Safety Evaluation Review Items have been addressed as documented in Reference 8 or Attachment 2 of thisletter. The North Anna Power Station, Unit 2 strategies are in compliance with Order EA-12-049.Page 2 of 5 Serial No. 14-394ADocket No. 50-339Compliance with EA 12-049Attachment 1MODIFICATIONS

-COMPLETEThe modifications required to support the FLEX strategies for North Anna Power Station,Unit 2 have been completed in accordance with the station design control process.EQUIPMENT

-PROCURED AND MAINTENANCE

& TESTING -COMPLETEThe equipment required to implement the FLEX strategies for North Anna Power Station,Unit 2 has been procured in accordance with NEI 12-06, Section 11.1 and 11.2, received atNorth Anna Power Station, initially tested, the performance verified as identified in NEI 12-06,Section 11.5, and is available for use.Maintenance and testing will be conducted through the use of the North Anna Power StationPreventative Maintenance program such that equipment reliability is maintained.

PROTECTED STORAGE -COMPLETEThe storage facility required to protect BDB equipment has been completed for North AnnaPower Station.

The BDB equipment is protected from the applicable site hazards and willremain deployable to assure implementation of the FLEX strategies for North Anna PowerStation, Unit 2.PROCEDURES

-COMPLETEFLEX Support Guidelines (FSGs), for North Anna Power Station, Unit 2, have beendeveloped and integrated with existing procedures.

The FSGs and affected existingprocedures have been approved and are available for use in accordance with the siteprocedure control program.TRAINING

-COMPLETETraining of personnel responsible for the mitigation of beyond-design-basis events at NorthAnna Power Station, Unit 2 has been completed in accordance with an accepted trainingprocess as recommended in NEI 12-06, Section 11.6.STAFFING

-COMPLETEThe staffing study for North Anna Power Station has been completed in accordance with"Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f)Regarding Recommendations 2.1, 2.3, and 9.3, of the Near-Term Task Force Review ofInsights from the Fukushima Dai-ichi Accident,"

Enclosure 5 pertaining to Recommendation 9.3, dated March 12, 2012 (Reference 9), as documented in letter dated May 7, 2014, "NorthAnna Power Station Units 1 and 2, March 12, 2012 Information

Request, Phase 2 StaffingAssessment Report,"

(Reference 10), and in the response to a Request for Additional Information (Reference

11) Regarding Phase 2 Staffing Assessment Report,Recommendation 9.3, dated September 22, 2014.Page 3 of 5 Serial No. 14-394ADocket No. 50-339Compliance with EA 12-049Attachment 1FSG strategies can be successfully implemented using the current minimum on-shift staffing.

NATIONAL SAFER RESPONSE CENTERS -COMPLETEDominion has established a contract with Pooled Equipment Inventory Company (PEICo) andhas joined the Strategic Alliance for FLEX Emergency Response (SAFER) Team Equipment Committee for off-site facility coordination.

It has been confirmed that PEICo is ready tosupport North Anna Power Station with Phase 3 equipment stored in the National SAFERResponse Centers in accordance with the site specific SAFER Response Plan(Reference 12).VALIDATION

-COMPLETEDominion has completed validation testing of the FLEX strategies for North Anna PowerStation, Unit 2 in accordance with industry developed guidance.

The validations assure thatrequired tasks, manual actions, and decisions for FLEX strategies are feasible and may beexecuted within the constraints identified in the Overall Integrated Plan (OIP)/Final Integrated Plan (FIP) for Order EA-12-049.

The FIP for North Anna Power Station, Units 1 and 2, will besubmitted no later than 60 days following the end of the North Anna Unit 1 second refueling outage following submittal of the OIP, currently scheduled for Spring 2015.FLEX PROGRAM DOCUMENT

-ESTABLISHED The Dominion FLEX Program Document has been developed in accordance with therequirements of NEI 12-06 and is in effect for North Anna Power Station, Unit 2.REFERENCES The following references support the North Anna Power Station, Unit 2 FLEX Compliance Summary:1. North Anna Power Station Units 1 and 2, "Overall Integrated Plan in Response to March12, 2012 Commission Order Modifying Licenses with Regard to Requirements forMitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049)," February 28, 2013 (ML13063A182).

2. NRC Order Number EA-12-049, "Order Modifying Licenses with Regard toRequirements for Mitigation Strategies for Beyond-Design-Basis External Events,"

datedMarch 12, 2012 (ML12229A174).

3. Letter from Dominion to NRC, "North Anna Power Station Units 1 and 2 Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenseswith Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis ExternalEvents (Order Number EA-12-049),"

dated August 23, 2013 (ML13242A012).

Page 4 of 5 Serial No. 14-394ADocket No. 50-339Compliance with EA 12-049Attachment 1REFERENCES (CONTINUED)

4. Letter from Dominion to NRC, "North Anna Power Station Units 1 and 2 Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenseswith Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis ExternalEvents (Order Number EA-12-049),"

dated February 27, 2014 (ML14069A012).

5. Letter from Dominion to NRC, "North Anna Power Station Units 1 and 2 Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenseswith Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis ExternalEvents (Order Number EA-12-049),"

dated August 28, 2014 (ML14251A024).

6. Letter from Dominion to NRC, "Supplement to Overall Integrated Plan in Response toMarch 12, 2012 Commission Order Modifying Licenses with Regard to Requirements forMitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049)," dated April 30, 2013 (ML13126A207).

7. NRC letter to All Operating Reactor Licensees and Holders of Construction Permits,"Nuclear Regulatory Commission Audits of Licensee Responses to Mitigation Strategies Order EA-12-049,"

dated August 28, 2013 (ML13234A503).

8. NRC letter from John Boska, Senior Project Manager, JLD, Office of NRR, to David A.Heacock, President and chief Nuclear Officer, Virginia Electric and Power Company,"NRC North Anna Power Station, Units 1 and 2 -Report for the Onsite Audit Regarding Implementation of Mitigating Strategies and Reliable Spend Fuel Instrumentation Related to Orders EA-12-049 and EA-12-051,"

dated September 24, 2014(ML14259A458).

9. 10CFR50.54(f),

"Request for Information Pursuant to Title 10 of the Code of FederalRecommendations 2.1, 2.3, and 9.3, of the Near-Term Task Force Review of Insightsfrom the Fukushima Dai-ichi Accident,"

Recommendation 9.3, dated March 12, 2012(ML2073A348).

10. Letter from Dominion to NRC, "North Anna Power Station Units 1 and 2, March 12, 2012Information Request Phase 2 Staffing Assessment Report,"

May 7, 2014(ML14133A01 1).11. Letter from Dominion to NRC, "North Anna Power Station Units 1 and 2, March 12, 2012Response to Request for Additional Information Regarding Phase 2 StaffingAssessment Report Recommendation 9.3," dated September 22, 2014.12. NRC letter from Jack Davis, JLD, Office of NRR, to Joseph E. Pollock, Vice President, Nuclear Operations, NEI, "Staff Assessment of National Safer Response CentersEstablished in Response to Order EA-12-049,"

September 26, 2014 (ML14265A107).

13. NRC letter from Jeremy S. Bowen, Chief, Mitigating Strategies Branch Office of NRR, toDavid A. Heacock, President and Chief Nuclear Officer, Virginia Electric and PowerCompany, "North Anna Power Station, Units 1 and 2 -Interim Staff Evaluation Relatedto Overall Integrated Plan in Response to Order EA-12-049 (Mitigating Strategies),"

dated January 29, 2014 (ML13338A445).

Page 5 of 5 Serial No. 14-394ADocket No. 50-339Attachment 2Response to Interim Staff Evaluation (ISE) Open Items and ISE Confirmatory Items plusAdditional Items Identified in Attachments 4 and 5 of the North Anna Power Station UnitsI and 2 Onsite Audit Report, September 24, 2014Virginia Electric and Power CompanyNorth Anna Power Station Unit 2 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2Response to Interim Staff Evaluation (ISE) Open Items and ISE Confirmatory Items plusAdditional Items Identified in Attachments 4 and 5 of the North Anna Power Station Units 1and 2 Onsite Audit Report, September 24, 2014ISE Open Item (01) 3.2.1.2.B Demonstration of the acceptability of the use the Flowserve N-9000 seals with theAbeyance feature and validation of an acceptable leakage rate for these seals.Dominion

Response

The acceptability of the use of Flowserve N-9000 seals with the Abeyance feature asreplacement seals for the North Anna reactor coolant pumps was evaluated as part of theDominion Design Control Program.

The replacement seals were approved for useconsistent with the requirements of 10 CFR 50.59. In the Flowserve document "WhitePaper on the Response for the N-Seal Reactor Coolant Pump (RCP) Seal Package toExtended Loss of AC Power (ELAP),"

Revision 0, dated February 11, 2014 (Proprietary),

Flowserve documented that, for an ELAP event followed by cooldown anddepressurization to a temperature range of 350 OF to 425 °F within six hours, degradation of elastomers in the three primary N-seal stages is not likely, and the expected RCP sealleakage would be limited to the Controlled Bleedoff (CBO) rate at normal operating temperature and pressure conditions.

This expected seal leakage is a small percentage ofthe leakage value assumed in the Reference NOTRUMP ELAP analysis in WCAP-17601 applied for North Anna. A copy of the white paper has previously been provided to theNRC staff and is available for their review.North Anna plans to initiate a cooldown/depressurization no later than two hours afterdeclaration of an ELAP event. At that time, the maximum temperature of the RCS will be5560F. In accordance with existing Emergency Operating Procedures, cooldown willproceed at 70-100°F per hour, ending at an RCS temperature of -4190F. The Flowserve white paper documents a test that exceeds the temperature for the North Anna RCP N-9000 seals during approximately the first 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months of the ELAP. The integration of thetemperature difference between the test temperature and the seal temperature during theELAP, when converted using the Arrhenius equation to estimate material degradation, shows that the N-9000 seals can remain at 419°F for more than a day before leakageincreases.

The initial leakage is minimal and improves the RCS response significantly relative to the Westinghouse high temperature seal package.

The additional leakage alsooccurs well after the RCS makeup pump is deployed and installed for RCS inventory makeup.Page 1 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE 01 3.2.1.8.A The Pressurized-Water Reactor Owners Group (PWROG) submitted to NRC a positionpaper, dated August 15, 2013 (ADAMS Accession No. ML13235A135 (non-public forproprietary reasons)),

which provides test data regarding boric acid mixing under single-phase natural circulation conditions and outlined applicability conditions intended to ensurethat boric acid addition and mixing would occur under conditions similar to those for whichboric acid mixing data is available.

During the audit process, the licensee informed theNRC staff that its boric acid mixing model is based on the PWROG method. Since theaudit discussions, the NRC endorsed the PWROG guidance with several clarifications inthe letter dated January 8, 2014. The licensee should address the clarifications inalignment with the NRC endorsement letter for the development of an adequate model fordetermining the mixing of boric acid in the reactor coolant system during natural circulation with the potential for two-phase flow conditions.

Dominion

Response

The NRC staff clarifications to the PWROG's position paper on boron mixing areaddressed as follows.Clarification (1): The North Anna evaluation for boron mixing has considered both thecase of maximum RCP seal leakage (21 gpm total), as well as the zero leakage case.Westinghouse Letter LTR-FSE-13-46, Revision 0, "Westinghouse Response to NRCGeneric Request for Additional Information (RAI) on Boron Mixing in Support of thePressurized Water Reactor Owners Group (PWROG),"

August 15, 2013 argued that thezero leakage case is more limiting than the high leakage case from the standpoint ofmixing because it delays the boron contribution from accumulator injection, resulting inmore reliance on pumped injection from the RCS FLEX pump. However, Dominion hasnot credited boron from accumulator injection in developing its FLEX strategy.

Therefore, the maximum leakage case is the most limiting.

A copy of LTR-FSE-13-46 has previously been provided to the NRC staff and is available for their review.Clarification (2): For the maximum leakage case, North Anna intends to initiate RCSmakeup of 45 gpm by the 16th hour following the onset of the ELAP/LUHS condition.

Thisis well in excess of the maximum RCS leakage at 16 hours1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months (see WCAP-17601 Figure5.2.2-6, Total RCS Leakage Flow). Westinghouse Letter LIS-14-79

, "PWROG ASCReflux Cooling Position Paper for Westinghouse Designed PWRs," Attachment 1,calculated that for a 3-loop Westinghouse plant, such as North Anna, the time at whichtwo-phase flow drops below single phase natural circulation flow is slightly more than 17hours. Since makeup flow will begin prior to this time and will exceed that maximumleakage flow, the approach to the condition where two-phase flow drops below singlephase natural circulation flow would be halted and, in fact, reversed.

Accordingly, theconditions identified in 2a are applicable as the RCS flow stays within the favorable conditions identified for boron mixing The conditions identified in 2b will not occur with thePage 2 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2above RCS makeup strategy.

A copy of LTR-FSE-14-79 has previously been provided tothe NRC staff and is available for their review.Clarification (3): Provided that the flow in all loops is greater than or equal to thecorresponding single-phase natural circulation flow rate, the staff considers a mixing delayperiod of one hour following the addition of the targeted quantity of boric acid to the reactorcoolant system to be appropriate.

Dominion's reactivity calculations show that no increasein boron concentration is required prior to 37 hours4.282407e-4 days 0.0103 hours 6.117725e-5 weeks 1.40785e-5 months for steam pressures down to the 290psig target steam pressure in ECA-0.0.

Cooldown below this point is not anticipated untilbeyond Phase 2. Thus, available boron mixing time will be approximately 21 hours2.430556e-4 days 0.00583 hours 3.472222e-5 weeks 7.9905e-6 months (37hours -16 hours) which is much greater that the one hour specified in Clarification (3).It should be noted that the North Anna maximum RCP seal leakage was determined to belarger for the Westinghouse RCP seals as a result of NSAL-14-1.

This change results inno impact to boron mixing since for Unit 2, 2 of 3 Westinghouse RCP seals have beenreplaced with the Flowserve N-9000 low leakage seals. Therefore, the RCP leakage rateassumptions in the analysis remain bounding for NAPS Unit 2.Page 3 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE CI 3.1.1.1.A Storage & Protection of FLEX equipment

-Confirm final design of FLEX storage structure conforms to NEI 12-06, Sections 5.3.1, 6.2.3.1, 7.3.1, and 8.3.1 for storage considerations for the hazards applicable to North Anna.Dominion

Response

The North Anna BDB Storage Building has been constructed per the specifications provided in Design Change (DC) NA-13-00061.

The design of the BDB Storage Buildingfor North Anna conforms to NEI 12-06, Sections 5.3.1, 6.2.3.1, 7.3.1, and 8.3.1 for storageconsiderations for the hazards applicable to North Anna as follows:Section 5.3.1: The North Anna BDB Storage Building has been designed to meet orexceed NEI 12-06, Section 5.3.1.1.a

(... a Structure that meets the plant's design basis forthe Safe Shutdown Earthquake (SSE)). The actual criteria used for the design of the NorthAnna BDB Storage Building is in accordance with Dominion Specification CV-0004 whichstates, "Earthquake motion in terms of acceleration response spectra (in horizontal andvertical directions) at bedrock corresponding to the 8/23/11 earthquake and the designbasis earthquake (DBE) site ground response spectra for soil-founded structures shall beconsidered.

The Supplier shall use the governing earthquake data between the two." Thefinal vendor calculation, IND1312902, confirmed compliance with Dominion Specification CV-0004 and has previously been provided to the NRC staff and is available for theirreview.Per Section 5.3.1.2, large portable FLEX equipment have been evaluated and are securedas described in Section 11.1.1 of ETE-CPR-2012-0012 to protect them during a designbasis seismic event. ETE-CPR-2012-0012 has been previously provided to the NRC staffand is available for their review.Per Section 5.3.1.3, the stored equipment and structures have been evaluated andprotected, as appropriate, from seismic interactions to ensure that unsecured and/or non-seismic components do not damage equipment.

This includes shelving which is requiredto be secured, appropriately loaded, or in an area clear of interactions.

Section 6.2.3: The North Anna BDB Storage Building has been designed to NEI 12-06,Section 6.2.3.1.1.a

(...is located above the flood elevation from the most recent site floodanalysis) and is not in an area that is subject to a rapid rise of water. Specifically, theNorth Anna BDB Storage Building has a finished floor elevation of 309.5 feet, which is wellabove the Probable Maximum Flood (PMF) water elevation of approximately 267.4 feet.The PMF level was taken from the Flood Hazard Re-evaluation Report (ADAMS Accession No. ML13318A090) for North Anna requested by the 10 CFR 50.54(f) letter dated March12, 2012. The general grade around the BDB Storage Building location slopes away fromthe building thereby minimizing the possibility of significant water accumulation or pondingin the area.Page 4 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2Section 7.3.1: The North Anna BDB Storage Building has been designed to NEI 12-06,Section 7.3.1.1.a

(...a structure that meets the plant's design basis for high wind hazards).

The actual criteria being used for the design of the North Anna BDB Storage Building is inaccordance with Dominion Specification CV-0004 which states, the minimum designtornado wind load is "360 mph (approximately 332 psf) with a pressure drop of 3 psi in 3seconds (300 mph rotational

velocity, 60 mph translational velocity with 1000 ft overalldiameter).

The maximum wind pressure shall be multiplied by applicable shape factors anddrag coefficients as given in ASCE Paper 3269 and applied to the silhouette of thestructure."

The final vendor calculation, IND1312902, confirms compliance with DominionSpecification CV-0004, and has previously been provided to the NRC staff and is available for their review.Section 8.3.1: The North Anna BDB Storage Building has been designed to NEI 12-06,Section 8.3.1.1.a

(...a structure that meets the plant's design basis for snow, ice and coldconditions).

The actual criteria used for the design of the North Anna BDB StorageBuilding is in accordance with Dominion Specification CV-0004 which states, "The designof the HVAC systems shall be based on maintaining the following indoor design conditions:

Heating:

minimum indoor temperature of 500F; Cooling:

maximum indoor temperature of1000F." This ensures that the FLEX equipment stored in the BDB Storage Building ismaintained within its design limits of 35°F to 1150F. The design basis high and lowtemperatures for North Anna are provided in Section A.1 of the North Anna OverallIntegrated Plan dated February 28, 2012 (ADAMS Accession No. ML13036A182) and theUFSAR.Page 5 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE CI 3.1.1.3.A Procedural Interface Considerations (Seismic)

-Confirm FLEX support guideline toprovide operators with direction on how to establish alternate monitoring and controlcapabilities.

Dominion

Response

FLEX Support Guidelines (FSG) 1/2-FSG-7, "Loss of Vital Instrumentation or ControlPower," have been confirmed to provide operators with direction on how to establish alternate monitoring and control capabilities.

1/2-FSG-7 include:

1) instructions to restorepower to the Remote Monitoring Panel to facilitate reading critical RCS and SGparameters,

2) instructions to obtain key parameter information reading from penetrations, and 3) instructions to read Core exit thermocouples using a battery powered thermocouple calibrator.

1/2-FSG-7 have been developed in accordance with Pressurized WaterReactor Owner's Group (PWROG) guidance and were approved prior to FLEXimplementation at North Anna Power Station.

Copies of the approved North Anna FSGshave previously been provided to the NRC staff and are available for their review.Page 6 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE CI 3.1.1.4.A Off-Site Resources

-Confirm RRC local staging area, evaluation of access routes, andmethod of transportation to the site.Dominion

Response

The National SAFER Response Center (NSRC -previously designated as the RRC) localstaging areas, access route evaluations, and transportation evaluations to the site havebeen completed and documented in the SAFER Trip Report for North Anna Power Station.The SAFER Response Plan for North Anna has also been finalized.

Copies of thesedocuments have previously been provided to the NRC staff and are available for theirreview.In response to questions received during the May 2014 NRC Onsite Audit, the following additional information is provided:

1) The gravel parking lot located south of the station access road from the new BDBStorage Building has been designated as the Staging Area "B" for equipment to bedelivered by helicopter from the NSRC. A clear area of 250' x 250' has been specified tothe NSRC for consideration of what helicopter to use to fly in equipment.

The overall areathat is available for staging equipment is greater (approximately 270 ft. X 600+ ft.) thanthe clear area dimensions that have been specified to the NSRC for their resourceplanning.

2) The staging area is slightly sloped to maintain appropriate drainage.

However, anyequipment or material that is delivered to this staging area will be assessed for stability and will be chocked as necessary to prohibit rolling.3) Liquefaction of Staging Area B has been evaluated.

Staging Area B was not initially included in the evaluation of liquefaction potential performed for the BDB Storage Buildingand haul routes, however, it is adjacent to these areas and no problems were anticipated.

Subsequently, a review of available construction test records and construction specifications was performed.

Based upon these test records and the test locationelevations it is evident that several feet of fill have been placed in the area that meet orexceed the required compaction density.

Using the required

density, established with theModified Proctor Test (ASTM D 1557), as a basis of estimating a relative density for theSM and SW-SM soils placed to construct the parking area (Staging Area "B") andcorresponding N60 value, the compacted soils are expected to exhibit N-values in excessof 30 blows per foot. Such soils and associated compactness will typically not liquefy in aseismic event. Additionally, data from a test boring from Staging Area B located on thenorth side of the station access road and just outside of the BDB Storage Buildingdemonstrated similar characteristics as the borings for the BDB Storage Building; therefore, liquefaction is not a concern.Page 7 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment

24) Dominion has placed a decision point within Attachement 4 of procedure EP-AA-FLX-101, "Single Point of Contact."

Attachment 4, "Travel Route Assessment and DebrisRemoval Guidance" is used by Dominion's Single Point of Contact (SPOC) who isresponsible for interfaces with the SAFER organization as the NSRC Phase 3 equipment is traveling towards the station.

The procedural guidance was enhanced to include a stepthat states: "If projected road/haul paths from Staging Area C to the station areinaccessible or bridges have not been cleared by the State Emergency Management forNSRC ground transportation, then contact the SAFER SPOC to dispatch groundtransportation to Staging Area D for helicopter operation to the station."

5) In a joint effort with the SAFER organization, Dominion's Beyond Design Basis (BDB)and Emergency Preparedness (EP) groups, conducted an information sharing session inApril 2014 titled, "Industry Approach to Addressing Order EA-12-049 Mitigating Strategies."

This session was attended by both state and local counties emergency responders andwas conducted at the Virginia's State Emergency Operations Center. Local countyrepresentative from both the Surry and North Anna sites were in attendance.

The sessionconsisted of a joint presentation by Dominion's BDB group and the SAFER organization onwhat is a Beyond Design Basis External Event (BDBEE) and also addressed Dominion's BDB Mitigating Strategies which included the SAFER organization's response to aBDBEE. The presentation was followed by a Q&A session.

Also, EP holds periodicmeetings with the local county officials to ensure offsite agencies are aware of and willsupport emergency situations such as BDB External Events in accordance with Dominion's Emergency Response Plan.Page 8 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE CI 3.1.5.2.A In the Integrated Plan, the licensee did not address considerations for any manual actionsrequired by plant personnel in high temperature conditions as recommended in NEI 12-06,Section 9.3.2. Discuss effects of high temperatures on any manual action performed byplant personnel and any applicable contingencies.

Dominion

Response

During an ELAP on site, ventilation providing cooling to occupied areas and areascontaining FLEX strategy equipment will be lost. Loss of ventilation analyses have beenperformed for North Anna to quantify the maximum steady state temperature reached inspecific areas to ensure the environmental conditions remain acceptable for personnel habitability and equipment qualification.

Calculation ME-0972 analyzes the heat-up of thefollowing areas during Phases 1 and 2 of the ELAP event to ensure the loss of forcedventilation and resulting room temperatures would not affect any credited mitigation equipment nor limit access of personnel required for performance of FLEX strategies:

-Main Control Room (MCR),-Emergency Switchgear Room (ESGR),-Main Steam Valve House (MSVH) S/G Power Operated Relief Valve(PORV) area,-Mechanical Equipment Room (MER) in the Turbine Building,

-Quench Spray (QS) Pumphouse,

-Auxiliary

Building, and-Auxiliary Feedwater (AFW) Pumphouse Turbine Driven AFW (TDAFW)Pump RoomResults of the analyses concluded no issues in terms of equipment function or personnel access for the duration of an ELAP with the exception of the TDAFW pump room. TheTDAFW pump room was previously analyzed in calculation 01040.4410-USB-268 fortemperature transients during a Station Blackoput (SBO). The analysis was based on theconservative assumption that the door to the AFW pumphouse was closed. With thisassumption, the TDAFW Pump Room maximum temperature was below 130 OF, but wasstill increasing at the end of the evaluation period (-8 hours). In order to consider thetemperatures achievable during the significantly longer time periods associated with anELAP event, calculation ME-0972 was amended to evaluate the TDAFW Pump Room withthe assumption that the TDAFW Pump Room door to the AFW Pumphouse was open.Under this assumption, the TDAFW Pump Room "steady state" temperature remains lessthan 120 °F.The North Anna Environmental Zone Description does not state a maximum ambienttemperature for the TDAFW Pump Room, but limits the temperature of the pumped AFWfluid to 120 OF. Calculation ME-0972 states that, since the steady state temperature in theTDAFW Pump Room remains below 120 OF, the temperature in this room is not expectedto adversely affect the performance or reliability of the pump or pump motor. Therefore, Page 9 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2taking the compensatory action to open the AFW Pumphouse door has been included inthe FLEX coping procedures which ensures acceptable temperatures following an ELAPevent. No other operator action to deploy portable ventilation equipment is expected to benecessary during the plant response to an ELAP.However, even at 120 OF, heat stress is a concern.

Therefore, for this area (or any areaswith elevated temperatures requiring access to implement the FLEX mitigating strategies),

current station procedures regarding heat stress management would be in effect.Procedure SA-AA-109, "Heat Stress Management" would be used to provide guidelines forstay times, the need for hydration, and to determine the need for cooling garments.

Copies of the calculations referenced above and procedure SA-AA-109 have previously been provided to the NRC staff and are available for their review.Page 10 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE CI 3.2.1.1.A Confirm that the use of NO TRUMP code for the ELAP analysis of North Anna is limited tothe flow conditions before reflux condensation initiates, including specification of anacceptable definition for reflux condensation cooling.Dominion

Response

The PWROG has documented the applicability of the NOTRUMP code for the evaluation of the ELAP event and application of its results with regards to criteria for boron mixing andreflux cooling for Westinghouse designed PWRs in PWROG-14064.

PWROG-14064 provides a comparison of results from the NOTRUMP and NRC's TRACE computer codesfor the parameters of interest and shows that the NOTRUMP predicted results agree wellor are conservative with respect to the TRACE predicted results.

Furthermore, thecomparison shows that NOTRUMP provides a conservative estimate of the required timewhen the RCS Injection pumps are required for an ELAP event as compared to TRACE.Therefore, it is concluded that NOTRUMP is acceptable for simulation of the ELAP eventwhen used within the criteria for reflux cooling and boron mixing.The definition of reflux cooling can be related to the quality in the SG U-bend region. FromPWROG-14064, the onset of "reflux cooling" is considered to exist when the one hourcentered moving average flow quality of the steam generator U-bend flow quality hasincreased to a value of 0.1 in any one loop. This condition is considered to be conservative since it is defined prior to either the onset of inadequate boron mixing in the RCP suctionleg or reflux cooling heat transfer.

That is, when this set of circumstances occurs, thedilution process in the RCP suction legs has not yet started.

As such, the RCS has not yetreached a stratified state where true reflux cooling heat transfer is possible.

Thus, thedefinition of the onset of reflux cooling is conservative for establishing the time when RCSmakeup is desired.The PWROG has documented leakage rates for Westinghouse RCP Original Equipment Manufacturer (OEM) Seals in PWROG-14015, Revision 1 using a bounding plantconfiguration.

The initial leakage information consisted of three points: initial leakage atnormal operating temperature and normal operating pressure (NOT/NOP);

peak leakage at1500 psia; and leakage at the cooled-down, depressurized conditions.

Additional studieshave been documented in PWROG-14015, Revision 1 to evaluate the linear assumptions between points and the effect of minimal subcooling for Category 1 seals. Theintermediate flow rates are slightly above what is predicted by the linear assumption forseal leakage between the Revision 0 points. The seal leakage flow rate is almostunaffected from the change from 50F of sub-cooling to less than 1IF of sub-cooling.

Foreach pressure

analyzed, these points are within 0.1 gpm.ETE-NAF-2012-0150, Revision 2, documents the time to reach the onset of reflux coolingin order to validate the time RCS makeup should be initiated for North Anna Units 1 and 2.The configuration for North Anna Unit 2 is now, subsequent to the Fall 2014 refueling Page 11 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2outage, one Westinghouse RCP OEM seal and two Flowserve RCP seals. ETE-NAF-2012-0150, Revision 2 incorporates the Westinghouse RCP OEM seal leakage valuesfrom PWROG-14015, Revision 1 for Category 3, and the normal response leakage for theFlowserve seal. As documented in Attachment G, as of the compliance date for NorthAnna Unit 2 (October 8, 2014) the estimated time to reach reflux cooling is 17.6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months withthe configuration of one Westinghouse OEM seal and two Flowserve seals; and a marginof 1.6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months is available to the established time of 16 hours1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months for the implementation of theRCS makeup pump.The PWROG documents and ETE-NAF-2012-0150, Revision 2 have previously beenprovided to the NRC staff and are available for their review.Page 12 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE CI 3.2.1.1.B Confirmation that the generic analysis in Section 5.2.1 of WCAP-17601-P is applicable orbounding with respect to North Anna for an appropriate figure of merit for defining entryinto the reflux condensation cooling mode.Dominion

Response

The Pressurized Water Reactor Owner's Group (PWROG) documented the applicability ofthe NOTRUMP code for the evaluation of the ELAP event and application of its results withregards to criteria for boron mixing and reflux cooling for Westinghouse designed PWRs inPWROG-14064.

PWROG-14064 provides a comparison of results from the NOTRUMPand TRACE computer codes for the parameters of interest and shows that the NOTRUMPpredicted results agree well, or are conservative, with respect to the TRACE predicted results.

Further, the comparison shows that NOTRUMP provides a conservative estimateof the required time when the primary make-up pumps are required for an ELAP event ascompared to TRACE. Therefore, it is concluded that NOTRUMP is acceptable forsimulation of the ELAP event within the constraints with regards to reflux cooling andboron mixing.Section 5.2.1 of WCAP-17601 provides a Reference Case which assumes standard RCPseal packages to determine the minimum adequate core cooling time with respect to RCSinventory (i.e., core uncovery).

The Reference Case models a Westinghouse 4-loop plantwith a core height of 12 feet (i.e., a 412 plant), a Tcold upper head, at 3723 MWt, with aModel F steam generator and Model 93A/A-1 reactor coolant pumps.PWROG-14064 indicates that the initiation time for reflux cooling will be set to 17.0 hour0 days 0 hours 0 weeks 0 months sfor the WCAP-17601, Section 5.2.1, Westinghouse 4-loop TcoId Reference Case.PWROG-14064 also indicates that 17.0 hours0 days 0 hours 0 weeks 0 months will be used, as a conservative basis, forWestinghouse 3-loop Thot upper head plant (i.e., for North Anna Units 1 and 2).The PWROG issued parameter templates for the reference cases presented in WCAP-17601 and WCAP-17792 that delineated the values for the important parameter used inthe analyses.

Table F.3 in ETE-NAF-2012-0150, Revision 2 provides these parameter values as compiled for North Anna Power Station (NAPS), Units 1 and 2. These NAPSplant values are available from the UFSAR and are, in general, only slightly different fromthe PWROG issued parameter templates.

(This is expected because the 3-LoopReference Case in WCAP-17792 is a representation of North Anna.) Therefore, theWestinghouse 3-Loop Thot Reference Case from WCAP-17792 is representative of NorthAnna.The WCAPs, PWROG documents, and ETE-NAF-2012-0150, Revision 2 have previously been provided to the NRC staff and are available for their review.Page 13 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE CI 3.2.1.1.C Confirm the consistency of the margin imposed to prevent accumulator nitrogen injection with the cooldown terminus assumed in WCAP-17601-P Dominion ResponseThe generic analysis applicable to North Anna is presented in WCAP-17601, Section5.2.1. The analysis assumes that the RCS cooldown/

depressurization is terminated at asteam pressure of 300 psia. North Anna procedure ECA-0.0, "Loss of All AC Power,"specifies terminating the cooldown at a steam pressure of 290 psig (approximately 305psia), which is conservative relative to the WCAP-17601 terminus with respect topreventing accumulator nitrogen injection.

Terminating the cooldown at 290 psig retainsthe 100 psi margin to accumulator nitrogen injection, which is stated as potentially occurring at 190 psig in ECA-0.0.

A copy of procedure ECA-0.0 has previously beenprovided to the NRC staff and is available for their review.Page 14 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE CI 3.2.1.2.C (1) Confirm that stresses resulting from a cooldown of the RCS will not result in the failureof seal materials.

(2) As applicable, confirm that reestablishing cooling to the seals willnot result in increased leakage due to thermal shock.Dominion

Response

The following responses are applicable to RCPs with Westinghouse Seals:(1) North Anna procedure ECA-0.0, "Loss of All AC Power," limits the RCS cooldown rateto 100°F/hr.

This constraint on cooldown rate is based on protecting the RCP sealsfrom damage due to thermal shock. A copy of procedure ECA-0.0 has previously beenprovided to the NRC staff and is available for their review. The Westinghouse Owner'sGroup Emergency Response Guidelines Background Documents recommend that theintact steam generators should be depressurized

quickly, to cool the RCS and minimizeRCP seal degradation and resultant inventory loss, but not so rapidly as to thermally shock the RCP seals, at a rate limited to 100°F/hr.

(2) Emergency response procedures direct that the intact steam generators aredepressurized to reduce primary system temperature, thus cooling the seals. Sealinjection and/or thermal barrier cooling are not restored following a loss of all ac powerevent until the RCS is cooled to cold shutdown conditions to prevent thermal shock orincreased seal leakage.The following response is applicable to RCPs with Flowserve Seals:As described in Flowserve document "White Paper on the Response for the N-SealReactor Coolant Pump (RCP) Seal Package to Extended Loss of AC Power (ELAP),"Revision 0, dated February 11, 2014 (Proprietary),

the Flowserve N-Seal design has beendemonstrated by testing to have no negative effects from rapid cooling.

Therefore, it is notfeasible for RCS cooldown rate or seal cooling (seal injection or thermal barrier cooling)restoration to result in failure of Flowserve N-9000 seal materials or increased sealleakage due to thermal shock. A copy of the white paper has previously been provided tothe NRC staff and is available for their review.Page 15 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE CI 3.2.1.6.A Sequence of Events -Confirm that the final timeline has been time validated after detaileddesigns are completed and procedures are developed.

The results will be provided in afuture 6-month update.Dominion

Response

The validation of response times for the North Anna FLEX Mitigation Strategies wascompleted on 09/30/14 during the Verification and Validation (V&V) phase of the FSGdevelopment/ECA-0.0 revision process.

There were no significant changes to the timeline.

The results of the validation effort have been documented in ETE-CPR-2014-1004, "NorthAnna BDB Validation of Time Sensitive Actions."

A copy of ETE-CPR-2014-1004 haspreviously been provided to the NRC staff and is available for their review.Page 16 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE CI 3.2.1.8.B Complete calculations demonstrating adequate shutdown margin for North Anna in ELAPscenarios with and without seal leakage.Dominion

Response

Demonstration of adequate shutdown margin for the ELAP scenario is provided inCalculation MISC-1 1788, "Investigation of Reactivity Control during Extended StationBlackout

-North Anna Units 1 and 2," Revision

0. A copy of Calculation MISC-1 1788,Revision 0 has previously been provided to the NRC staff and is available for their review.Calculation MISC-11788 is based on the no RCS leakage case, which bounds the highleakage case modeled in WCAP-17601-P.

As documented in Calculation MISC-11788, for depressurization to the target ECA-0.0 secondary pressure of 290 psig, boron additionis not needed before 37 hours4.282407e-4 days 0.0103 hours 6.117725e-5 weeks 1.40785e-5 months to maintain K-effective

< 0.99. However, borated makeupwill be initiated well in advance of this time, i.e. at 16 hours1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months . Additionally, 2,600 gallons ofRWST water (or equivalent boron concentration) is required to borate the system to K-effective

= 0.99, at the xenon free condition.

This requirement is based on completemixing of the 2,600 gallons at 2,600 ppm with the initial RCS inventory.

Assuming therated BDB RCS Injection pump flow rate (45 gpm), this makeup can be added in just underan hour (i.e., by 17 hours1.967593e-4 days 0.00472 hours 2.810847e-5 weeks 6.4685e-6 months ).By comparison, for the high leakage case (all Westinghouse seals) modeled in WCAP-17601, Section 5.2.1, and shown in Figure 5.2.2-8, total RCS inventory has decreased toabout 88% of its initial value at 16 hours1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months (57,600 seconds) due to RCS leakage.

With RCSmass at about 88% of its initial value, the requirement for borated makeup to achieve theXenon-free reactivity requirement would be reduced from 2,600 gallons of RWST water toapproximately 2,300 gallons.

At the rated BDB RCS Injection pump flow rate (45 gpm), thismakeup can be achieved within about 51 minutes.

Note that the indicated leakage inFigure 5.2.2-8 is offset somewhat by accumulator injection between around 10,000 -15,000 seconds.

Dominion's reactivity analysis does not credit the boron concentration from the accumulators.

For either case (high leakage or low leakage),

deployment of theBDB RCS Injection pump by 16 hours1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months ensures that adequate boration is achievedapproximately 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months prior to any required increase (i.e., 37 hours4.282407e-4 days 0.0103 hours 6.117725e-5 weeks 1.40785e-5 months -16 hours -1 hour).Furthermore, deployment of the BDB RCS Injection pump by 16 hours1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months ensures that thereflux cooling condition is avoided and many hours of boron mixing time are available before the boron increase is required.

Page 17 of 54 Serial No. 14-394ADocket No. 50-339Order EA-1 2-049Attachment 2ISE CI 3.2.1.8.C Confirm that shutdown margin calculations will be verified to remain bounding for futureoperating cycles and clarify the method that will be used to make this determination.

Dominion

Response

A check has been incorporated into the normal reload design and safety analysis processto confirm that the ELAP reactivity analyses remains bounding for new cycle designs.

Asimple statepoint check has been incorporated into the North Anna section of theDominion standard for the Reload Safety Analysis

-Overview.

The appropriate statepoint for a reload core is the calculated boron concentration required for a 1 % shutdown margin(SDM) at the conditions of end-of-cycle (EOC), all control rods in (ARI), no xenon, and at290 psig steam pressure

(-419°F RCS cold leg temperature).

The corresponding statepoint value determined from the ELAP reactivity

analysis, Calculation MISC-1 1788, is131 ppm. Any significant increase from the statepoint value of 131 ppm would initiate amore detailed evaluation to determine the time at which boron addition would be requiredto maintain a 1% SDM considering time-dependent xenon reactivity.

The current ELAPreactivity analysis reference value is 37 hours4.282407e-4 days 0.0103 hours 6.117725e-5 weeks 1.40785e-5 months for this statepoint.

Any time less than 37hours would have to be justified through consideration of the margin available based onthe RCS make-up strategy.

Page 18 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE Cl 3.2.1.9.A Confirm that the licensee provides sufficient BDB RCS Injections Pumps to conform to thespare capability (N+ 1) guidance of NEI 12-06, Section 3.2.2.Dominion

Response

Two BDB RCS Injection pumps are sufficient to comply with the guidance of NEI 12-06,Section 3.2.2. If one of the two pumps stored in the on-site BDB Storage Building isinoperable, the operable pump may be used to supply RCS inventory makeup from eitherRefueling Water Storage Tank (RWST) to both units by alternating RCS injection betweenthe units.In this configuration, the RCS Injection pump would discharge to the alternate RCSInjection connection located in the Hydrogen Recombiner Vault so that the single pumpcan supply borated water to either unit through valve manipulation of the charging systemcross-tie piping. Flow is alternated between Unit 1 and Unit 2 by manually operating thenormal charging headers cross-tie valves. Components in this CVCS flow path are safety-related, seismically constructed/mounted and located in missile protected facilities.

Oncealigned, the transfer of flow from one unit to the other is controlled by two manual valves,one for each unit. Flow to the reactor coolant system will be through the Cold Leg injection path via the Boron Injection Tanks (BITs).RCS injection would begin with the BDB RCS Injection pump supplying makeup to the unitwith the lower indicated RCS inventory for approximately 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months , starting no later than 15hours from the onset of ELAP. One hour of RCS inventory addition at rated BDB RCSInjection pump flow rate (45 gpm) recovers more than 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months of RCP seal leakage at themaximum assumed Westinghouse seal leakage rate. The BDB RCS Injection pump wouldthen be used to supply makeup to the opposite unit for approximately 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months .The alternating RCS injection process would be repeated until either: 1) RCS level wasindicated in the pressurizer(s),

or 2) a replacement RCS Injection pump was received fromthe NSRC (approximately 28 hours3.240741e-4 days 0.00778 hours 4.62963e-5 weeks 1.0654e-5 months from the onset of the ELAP condition) and deployed forRCS makeup for one of the two units.[Note: Refer to the response to Safety Evaluation Review Item #8 for a discussion of thisscenario with no RWSTs available.]

Page 19 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE Cl 3.2.1.9.B Confirm that calculations documenting the AFW supply, SFP makeup, and RCS inventory hydraulic analysis demonstrate the pumps have adequate capacity for the strategies theysupport.Dominion

Response

Calculation ME-0966, "BDB High Capacity Pump and BDB AFW Pump Hydraulic Analysisfor Spent Fuel Pool Makeup and AFW Injection at NAPS Units 1 and 2," Revision 0documents the hydraulic analysis of the BDB High Capacity pump and the associated hoses and installed piping systems to confirm that the BDB High Capacity pump minimumflow rate and head capabilities exceed the FLEX strategy requirements for AFW supplyand SPF makeup. Calculation ME-0965, "Evaluate the BDB High Head Injection pump forBeyond Design Basis (BDB) at the primary and alternative supply locations in Modes 1-4and the BDB AFW Pump in Modes 5 and 6," Revision 0, documents the hydraulic analysisof the BDB RCS Injection pump with the associated hoses and installed piping systems toconfirm that the BDB RCS Injection pump minimum flow rate and head capabilities exceedthe FLEX strategy requirements for maintaining RCS inventory and controlling reactivity.

Calculations ME-0966 and ME-0965 have previously been provided to the Staff and areavailable for their review.Page 20 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE CI 3.2.2.ASFP venting -Confirm that opening of the roll-up doors would provide an adequateventilation path for the SFP area.Dominion

Response

The Fuel Building and the adjoining Decontamination Building have several large roll-updoors that when opened would allow significant airflow through the Fuel Building with nofans operating.

The Southeast section of the Fuel Building (South wall of the New Fuel Area Enclosure area), has an 18' wide by 16' high roll-up door (1-BLD-DR-FA71-3) which opens to theoutside.

Approximately 65' north of this door, there is an 18' wide by 20' high roll-up door(1-BLD-DR-F72-2) between the New Fuel Area Enclosure and the main Fuel Buildingarea. Both of these doors are at grade elevation (271') and when open establish a directpath of outside air to the lower level of the main Fuel Building.

In the Southwest corner of the Decontamination Building at elevation 291', there are two15' wide by 40' high rolling steel doors in series (1-BLD-DR-D91-2, 1-BLD-DR-D91-3).

The first door connects the Fuel Building to the Decontamination Building; the second doorconnects the Decontamination Building to the outside.

Together these doors, when open,establish a direct path from the upper portion of the main Fuel Building to the outside.Opening these roll-up doors in accordance with procedures provides a direct path for air toflow into the Fuel Building at elevation 271', over the SFP, and outside through the doorsat the 291' elevation.

Given the elevation difference between the mid-points of openings(approximately 30') and large open area (minimum opening of approximately 290 ft2),these open roll-up doors would allow significant natural circulation airflow through the FuelBuilding and provide an adequate ventilation path for the SFP area.In Attachment 5 of the North Anna Onsite Audit Report, Dominion was requested to"Provide SFP area habitability analysis and/or hose deployment strategy."

The responseto that request is as follows:A bounding estimate of the airborne contamination in the Fuel Building following anELAP event has been performed and is documented in ETE-CPR-2012-0012, Revision

5. The evaluation concluded that the expected maximum level of airbornecontamination in the Fuel Building following an ELAP / loss of SFP cooling eventwould not prevent implementation of any BDB FLEX strategies for SFP inventory makeup and cooling.

Therefore, deployment of hoses inside the Fuel Building at atime beyond 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months is acceptable.

A copy of ETE-CPR-2012-0012, Revision 5has previously been provided to the NRC staff and is available for their review.Page 21 of 54 Serial No. 14-394ADocket No. 50-339Order EA-1 2-049Attachment 2ISE CI 3.2.3.AContainment

-Confirm containment analysis to determine any containment temperature and pressure actions beyond 7 days.Dominion

Response

Overall Integrated Plan (OIP) Open Item No. 4 was completed and documented as"Complete" in the Six-Month Status Update letter dated February 27, 2014 (SN: 12-162E).

Section 4c and Attachment 2 of the update letter provided the Containment coolingstrategy.

Calculation MISC-1 1793, Revision 0, "Evaluation of Long-Term Containment Pressure andTemperature Profiles Following an Extended Loss of AC Power (ELAP),"

is a conservative

analysis, which concluded that Containment temperature and pressure response willremain below design limits following an ELAP event and that key parameter instrumentation subject to the Containment environment will remain functional for at leastseven days.As described in Chapter 5 of ETE-CPR-2012-0012, Revision 5, multiple Containment cooling methods are available as options to remove heat from Containment in order tomaintain the Contatinment temperature within the equipment design limits, However,these methods are not required to be specifically designated as primary and alternate strategies since they are Phase 3 actions and occur many days following the ELAP event.Adequate time is available utilizing onsite personnel resources and equipment receivedfrom the NSRC to deploy and implement the various Containment cooling methodsdescribed.

In documenting the closure for OIP Open Item No.4, it was indicated that OIP Open ItemNo. 5 would encompass the thermal and hydraulic calculations which would determine theadequacy of any containment temperature and pressure reduction actions beyond 7 days,if any. Calculation ME-12126, Revision 0, "FLEX Beyond Design Basis (BDB) ServiceWater (SW) Containment Integrity Strategy Hydraulic Analysis,"

was completed and hasconfirmed that the SW flows available based on NSRC supplied pumps for Containment cooling options are adequate.

OIP Open Item No. 5 was subsequently closed in theAugust 2014 Six-Month Status Report.Copies of ETE-CPR-2012-0012, Revision 5, Calculation MISC-1 1793, Revision 0 andCalculation ME-12126, Revision 0 have previously been provided to the NRC staff and areavailable for their review.Page 22 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE CI 3.2.4.2.A Ventilation

-Equipment Cooling -Confirm development of the ventilation strategy.

Dominion

Response

The commitment for Overall Integrated Plan (OIP) Open Item No. 13 for North Anna, wasto provide details of the ventilation strategy that conform to the guidance given in NEI 12-06. This information was provided and documented as "Complete" in the Six-Month StatusUpdate letter dated February 27, 2014 (SN: 12-162E).

Attachment 2 of the update letterprovided the ventilation strategy for North Anna following an ELAP event. Calculation ME-0972, Revision 0, Addendum A, "Evaluation of Room Air Temperatures Following Extended Loss of AC Power (ELAP),"

supporting the North Anna Unit 1 and 2 ventilation strategies has previously been provided to the NRC staff and is available for their review.In Attachment 5 of the North Anna Onsite Audit Report, Dominion was requested to"Provide the analysis assumptions for the actions specified in the FSGs." The response tothat request is as follows:The ventilation actions specified in FSG-5, "Initial Assessment and FLEX Equipment Staging,"

Step 7 involve the following:

1. Blocking open the doors to the Turbine Driven Auxiliary Feedwater (TDAFW) pumproom in each unit,2. Establishing natural circulation ventilation in the Fuel Building,

3. Establishing battery room exhaust fans when battery charging is initiated

4. Opening of equipment room doors, energized cabinet doors, and deployment ofportable fans.FSG-5 has previously been provided to the NRC staff and is available for their review.1. Regarding the basis for blocking the TDAFWP Rooms open, Section 13 ofCalculation ME-0972, Revision 0, Addendum A indicates:

"The bulk air temperature in the TDAFWP room will remain below 120 OF (119.4 OFas noted in Section 11) during an ELAP event, providing the room door to theoutside is opened within approximately 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months . Note that the NUMARC methoddoes not credit the heat sink effect of the floor or other steel in the room. Theanalysis also does not credit the effect of opening the supply and exhaustventilation dampers."

Sections 8 and 9 of Calculation ME-0972, Revision 0, Addendum A list all of thedesign inputs and analysis assumptions, respectively.

Calculation ME-0972,Revision 0, Addendum A, has previously been provided to the NRC staff and isavailable for their review.Page 23 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment

22. Regarding the basis for natural circulation in the Fuel Building, no analysis wasperformed since, by engineering

judgment, the configuration of Fuel Building doorswould be more than sufficient to support natural circulation ventilation through thestructure.

The response to NAPS ISE Cl 3.2.2.A provided the door sizes, locations, and elevations of the doors to be opened by Attachment 2 of FSG-5 (per Step 7).Additionally, during the May 2014 NRC Onsite Audit the Fuel Building area waswalked down and the ventilation path was identified.

3. Regarding the use of the battery room exhaust fans, no analysis was performed since the exhaust fans are required to be running in their normal plant configuration prior to energizing the battery chargers.

The temperature and hydrogenconsiderations for the battery rooms have been addressed in the responses to ISECl 3.2.4.2.B

4. Regarding the statements for opening equipment room doors, energized cabinetdoors, and deployment of portable fans, calculation ME-0972 concluded thatopening doors and cabinets in the Main Control Room and Emergency Switchgear Room would not be required.

This conclusion was based on GOTHIC analyses ofthese areas with no ventilation or cooling, coincident with loss of the heat loadduring an ELAP. The ventilation strategy for North Anna was provided for staffreview in Attachment 2 to the second Six-Month Status Report dated February 27,2014. In the ventilation strategy it was identified that, for the purpose of defense indepth, area temperatures would be monitored and opening doors and the use ofportable fans were available options.Page 24 of 54 Serial No. 14-394ADocket No. 50-339Order EA-1 2-049Attachment 2ISE CI 3.2.4.2.B Confirm the adequacy of the battery room ventilation provided in the context of an ELAP.Dominion

Response

North Anna Units 1 and 2 are designed with four battery rooms for each unit. Two batteryrooms are partitioned in each Emergency Switchgear Room (ESGR) at elevation 254'.The normal ventilation for these battery rooms is provided by recirculation of air via a smallexhaust fan on the top of the battery room which pulls air from the ESGR via an inlet nearthe floor and exhausts the air back into the ESGR. The other two battery rooms arelocated in each Cable Tray Spreading Room at elevation 294'. These rooms are aboveeach Main Control Room (MCR). The normal ventilations for these battery rooms isprovided by recirculation of air via a small fan in the battery room which pulls air from theMCR ceiling level and exhausts the air back into the MCR via an inlet near the floor. Thefire dampers in the inlet and exhaust openings for both of these battery room locations remain open on loss of power or during a design basis accident.

Explicit modeling of thefour battery rooms is not necessary since during battery discharge in Phase 1 of the ELAPscenario the exhaust fans are not operating and the heat addition internal to the batteryrooms from the batteries is negligible.

During Phase 2 when power is available to thebattery chargers and the ventilation fans are running, the rooms would essentially be inequilibrium with the areas associated with the recirculation paths, either the MCR or theESGR. There are no significant heat loads in the battery rooms and heat from thebatteries during re-charging is minimal.

Since FSG-4 requires the battery room fan to beoperating before starting the chargers, the battery room ventilation will be in its normalconfiguration, therefore, also accounting for the generation of hydrogen during charging.

The battery chargers are located in the ESGR and their heat loads were accounted for inCalculation ME-0972, Revision 0, Addendum A, "Evaluation of Room Air Temperatures Following Extended Loss of AC Power (ELAP)."

The calculation shows that the expectedloss of ventilation transient temperatures in the sources of suction for the battery roomventilation systems (i.e., the ESGR and CR) are expected to remain below 120°Findefinitely.

The impact of extreme low temperatures is not expected to be significant dueto the continuous connection with the CR and ESGR spaces and the heat storage capacityof the battery room concrete walls/floors/ceilings.

However, if decreasing battery roomtemperatures become a concern, the FSG procedures provide for the use of portableheating equipment.

A copy of FSG-4 and calculation ME-0972, Revision 0, Addendum Ahave previously been provided to the NRC staff and are available for their review.Page 25 of 54 Serial No. 14-394ADocket No. 50-339Order EA-1 2-049Attachment 2ISE Cl 3.2.4.4.A Verify the lighting study validates the adequacy of supplemental lighting and the adequacyand practicality of using portable lighting to perform FLEX strategy actions.Dominion

Response

In order to validate the adequacy of supplemental lighting and the adequacy andpracticality of using portable lighting to perform FLEX strategy

actions, an evaluation of thetasks to be performed and the available lighting in the designated task areas wascompleted.

The results are documented in Section 10.5 of ETE-CPR-2012-0012, Revisioin 5, "Beyond Design Basis Overall Integrated Plan Basis Document."

Tasksevaluated included traveling to/from the various areas necessary to implement the FLEXstrategies, making required mechanical and electrical connections, performing instrumentation monitoring, and component manipulations.

Battery Powered (Appendix "R") emergency lights were determined to provide adequate lighting for all primaryconnection points in the BDB Strategies including the illumination for all interior travelpathways needed to access the connection points. These emergency lights are designedand periodically tested to insure the battery pack will provide a minimum of 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months oflighting with no external AC power sources.

Prior to the depletion of the Appendix "R"lighting units, portable battery powered Remote Area Lighting Systems (RALS) would bedeployed to support the FLEX strategy tasks. These RALS's are rechargeable LEDlighting systems designed to power the LED lights for 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months at 6000 Lumens and 40hours at 500 lumens. In addition to installed Appendix "R" lighting, and the stored RALSsand portable light plants, the BDB storage building includes a stock of flashlights and headlights to further assist the staff responding to a BDB event during low light conditions.

There are no emergency lighting fixtures in the yard outside of the protected area toprovide necessary lighting in those areas where portable BDB equipment is to bedeployed.

Therefore, the diesel powered pumps and generators are outfitted with lightplants that are powered from their respective diesels to support connection and operation.

In addition to the lights installed on the portable BDB equipment, portable light plants areincluded in the FLEX response strategies.

These portable diesel powered light plants canbe deployed from the BDB Storage Building as needed to support night time operations.

A copy of ETE-CPR-2012-0012, Revision 5 has previously been provided to the NRC staffand is available for their review.Page 26 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE CI 3.2.4.4.B Communications

-Confirm the licensee's proposed enhancements and interim measuresto the site's communications systems and that they have been completed.

Dominion

Response

The study documenting the communications strategy has been completed.

Subsequently, Overall Integrated Plan (OIP) Open Item No. 18 was documented as "Complete" in theSix-Month Status Update letter dated February 27, 2014. The study concluded that FLEXstrategies can be effectively implemented with a combination of sound powered phones,satellite phones and hand-held radios. Although the overall communications plan has notchanged, the details regarding the components to be used and the number of components have continued to evolve. At this time, the quantity of components needed to implement the communications strategy has been determined to be 20 satellite phones, 30 hand heldradios, and 10 additional, dedicated sets of sound powered phone headsets and extension cords. Distribution of the satellite phones includes the Control Room (CR), the Technical Support Center (TSC), Security, Health Physics Survey Teams, and the surrounding county Offsite Response Organizations (OROs). The hand held radios are for commandand control of the FLEX mitigating strategies and include 10 spare radios and 3 batteries per device.The CR and TSC satellite phones are installed "desk set" units which required a plantDesign Change to be installed.

Design Change NA-14-01077 installed these satellite phones. The antennae setup will be a deployable system with fiber optics cable from theinside "desk sets" to outdoor portable dish antennae.

Handheld satellite phones areavailable and adequate for initial notifications.

This portion of the communications strategyis intended to suffice for approximately the first 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .Once augmented staff arrives on site, a mobile communications trailer designed to handleboth satellite voice and data traffic, as well as to function as a radio repeater to enhanceon-site communications, will be deployed from the BDB Storage Building.

The finalcommunications strategy has been completed and is detailed in ETE-CPR-2013-003, Revision

2. Copies of ETE-CPR-2013-0003, Revision 5 and Design Change NA-14-01077 have previously been provided to the NRC staff and are available for their review.In response to an additional question received during the May 2014 NRC Onsite Auditregarding the connections for the "desk set" satellite phones, the following detail isprovided:

Design Change NA-14-01077 installed the communications infrastructure in the plantrequired to ensure availability of off-site communications.

Three satellite phones, a Cisconetwork switch, and one UPS were installed in the Unit 1 Computer Room. Four satellite phones and a Cisco network switch are stored in the TSC Computer Room. The portablesatellite dish for deployment outdoors is permanently stored in the TSC HVAC Room.Page 27 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2ISE CI 3.2.4.8.A Electrical Power Sources -Confirm load calculations for the phase 2 and 3 FLEXgenerators will support supplied loads.Dominion

Response

The North Anna Phase 2 load calculations for the 120 VAC and the 480 VAC dieselgenerators (DGs), for Unit 1 (Calculation EE-863) and Unit 2 (Calculation EE-865) confirmthe BDB portable DGs are sized properly to support the required BDB loads. Additionally, the calculations include the determination of the corresponding cable ampacity rating alongwith the breaker settings and coordination with the North Anna system components.

The North Anna Unit 1 and 2 Phase 3 load calculation for the 4kV NSRC generator ratingand power cable ampacity rating (Calculation EE-871) confirm that 2 1MW NSRC EDGsare adequate to properly support the required BDB Phase 3 loads. Initially, calculation EE-871, was going to incorporate information regarding the breaker settings and coordination with the NAPS systems once the NSRC 4kV DG information/specs became available.

However, it was later determined that this revision was not required because the 4 kVgenerators are not needed for several days following an ELAP event and at that time,sufficient time and engineering resources will be available to address this interface.

Also,a breaker coordination study was not needed because, in addition to the existing NAPSsystem electrical protection

schemes, the NSRC generators and distribution panel areprotected by breakers that are sufficiently sized and tested to provide both equipment andpersonnel safety. If a fault occurs, the existing system/component breaker should trip. Inthe unlikely event that the NSRC breaker at the 4kV distribution panel would trip before theexisting faulted system/component

breaker, the fault would be located and isolated, theNSRC breaker would be reset, and the NSRC breaker would be adjusted if necessary toprovide appropriate coordination with the existing plant breakers.

NSRC personnel will beavailable to provide technical expertise to Dominion personnel during the startup andoperation of the 4kV generators.

Any coordination interface issues could be promptlyaddressed at that time.Copies of Calculations EE-863, EE-865, and EE-871 have previously been provided to theNRC staff and are available for their review.During the May 2014 NRC Onsite Audit, Dominion was requested to provide additional information regarding potential derating of the portable DGs due to high ambienttemperatures.

The response to this request is as follows:Performance data tables for altitude and temperature for both the 120/240 VAC and480 VAC DGs shows no derating at elevations corresponding to the North Anna siteelevation and for temperatures up to 120 Deg OF. Therefore, the 120/240 VAC andthe 480 VAC diesel generator loading calculations for North Anna did not addressderating due to high ambient temperatures.

The vendor supplied performance dataPage 28 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2showing no derating at the elevation corresponding to the North Anna site and fortemperatures up to 120 Deg OF for the 480 VAC DGs is shown in Attachment 13.5of Calculation EE-0863, Revision

2. This information is typical of both the 120/240and 480 VAC DGs.The 120/240 VAC DGs have approximately 20% margin between the maximumloads and the generator design capacity and the 480 VAC DGs have approximately 45% margin between the maximum loads and the generator design capacity.

Therefore, margin is available in the generator sizing to accommodate potential derating concerns.

Page 29 of 54 Serial No. 14-394ADocket No. 50-339Order EA-1 2-049Attachment 2ISE CI 3.2.4.9.A Fuel Supplies

-Confirm the adequacy of the fuel consumption evaluation.

Confirm thatthe procedural guidance governing re-fueling strategies addresses:

(a) how the quality ofthe fuel oil and gasoline supplies will be controlled in order to ensure proper diesel orgasoline-powered FLEX equipment operation, (b) available sources of gasoline and howthose sources will be protected to ensure availability following a BDB event, and (c) if theonsite fuel capacity provides an indefinite supply of fuel or if the RRC is capable ofproviding an indefinite, ongoing supply of fuel (both diesel and gasoline).

Dominion

Response

The BDB FLEX equipment includes a refueling tank truck. This truck is stored in the fullyprotected FLEX Storage Building and is used to refuel diesel fueled BDB event responseequipment.

This refueling truck has a capacity of 1100 gallons and is maintained approximately 80% full (880 gal). The tank truck is equipped with necessary pumps,hoses, meters and valve necessary to fill the truck and refuel the BDB equipment.

The re-fueling strategy (sources, frequencies, locations, etc.) is directed as part of the FSGs. Allof the key BDB equipment (generators, pumps, vehicles, etc.) is maintained with full tanksof fuel. This strategy helps protect the equipment from moisture accumulation in the fueland corrosion of the fuel tanks. In addition, this strategy will facilitate the promptdeployment and placing the BDB equipment in service following a BDB external event.Preventative maintenance will be performed to sample, condition and/or replace the fuel inall of the BDB equipment to insure proper fuel conditions are maintained for equipment operation.

The refueling tank truck is equipped with an on-board Blackmere TDA 2A pump drivenfrom the truck's PTO. This pump is used for filling the truck as well as refueling the BDBEquipment.

The pump has a variable flow rate adjustment with a max capacity of > 50GPM. The truck is also equipped with 125 ft. of 1" discharge hose and line nozzle forrefueling operations.

It is expected the truck can be filled in approximately 20 minutes.The fuel truck can be refilled from any of the three diesel fuel sources identified in Section10.7.1 of ETE-CPR-2012-0012, Revision 5, "Beyond Design Basis Overall Integrated PlanBasis Document" using the fuel truck's on-board fuel oil pump. Two of these diesel fuelsources are protected for all of the BDB hazards.

A copy of ETE-CPR-2012-0012, Revision 5 has previously been provided to the NRC staff and is available for their review.The table below identifies the components and fuel requirements to support the FLEXstrategy implementation.

Not all of the BDB equipment listed below (which includes theN+1 equipment) would be required and operating simultaneously at full load during a BDBexternal event response.

However, using a conservative combined fuel consumption rateof 120 Gal/hr, the refueling tank truck has sufficient capacity to support continuous operation of the major BDB equipment expected to be deployed and placed into servicefollowing a BDB external event. At this conservative fuel consumption rate, the twoprotected 45,000 gallon underground Fuel Oil Storage Tanks, which are protected for BDBPage 30 of 54 ISerial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment

2hazards, have adequate capacity to provide the on-site BDB equipment with diesel fuel for>30 days. The NSRC will also be able to provide diesel fuel for diesel operated equipment thus providing additional margin.The diesel fuel consumption information above does not include the large 4KV generators to be received from the RRC. More than adequate diesel fuel is available onsite for thesegenerators if the partially protected above ground 275,000 gallon Fuel Oil Storage Tank isavailable.

If it is not, provisions for receipt of diesel fuel from offsite sources would benecessary prior to implementing the Phase 3 re-powering strategy with the 4Kv dieselgenerators.

The BDB external event response strategy includes a very limited number of small supportequipment that is powered by gasoline engines (chain saws, chop saws and smallelectrical generator units). These components will be re-fueled using portable containers offuel. Gasoline fuel will be obtained from the station's two (2) 8,500 gal underground gasoline fuel storage tanks or from private vehicles on site. Gasoline Fuel sources arediscussed further in section 10.7.1 of ETE-CPR-2012-0012, Revision 5, "Beyond DesignBasis Overall Integrated Plan Basis Document".

North Anna BDB Equipment Diesel Fuel Consumption Evaluation Min. RunTank Max. Fuel Time Run TankComponent Capacity Usage Rate Time w/Full Construction TankBDB AFW Pump #1 275 Gal 10.9 Gal / Hr 24 hrs Double WallBDB AFW Pump #2 275 Gal 10.9 Gal / Hr 24 hrs Double WallBDB AFW Pump #3 275 Gal 10.9 Gal / Hr 24 hrs Double WallBDB RCS Injection 300 Gal 7.75 Gal / Hr 24 Hrs Double WallPump #1BDB RCS Injection 300 Gal 7.75 Gal / Hr 24 Hrs Double WallPump #2BDB HighCapacity*

500 Gal 14.3 Gal / Hr 30 Hrs Double WallPump #1 (GodwinHL130M)BDB High CapacityPump #2 (Godwin 175 Gal 11.7 Gal / Hr 15 Hrs Double WallHL5M B.5.b pump)Diesel Fire Pump* 220 Gal 13.2 Gal / Hr 16.5 Hrs Single WallPage 31 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2North Anna BDB Equipment Diesel Fuel Consumption Evaluation Min. RunTank Max. Fuel Time Run TankComponent Capacity Usage Rate Time w/Full Construction Tank480 VAC Gen #1 500 Gal 28.4 Gal / Hr 17 Hrs Double Wall480 VAC Gen #2 500 Gal 28.4 Gal / Hr 17 Hrs Double Wall480 VAC GenTC*500 Gal 28.4 Gal / Hr 17 Hrs Double WallTSC**120 VAC Gen #1 100 Gal 4.2 Gal / Hr*** 24 Hrs Double Wall120 VAC Gen #2 100 Gal 4.2 Gal / Hr*** 24 Hrs Double Wall120 VAC Gen #3 100 Gal 4.2 Gal / Hr*** 24 Hrs Double WallJohn Deere -John Tatr 58 Gal Varies Varies Single WallM6125 TractorJohn Deere -John Tatr 58 Gal Varies Varies Single WallM6125 TractorJohn Deere -Utility 6 Gal Varies Varies Single WallVehicle (Gator)Caterpillar 924 60 Gal Varies Varies Single WallloaderFuel Truck 40 Gal Varies Varies Single WallFuel Truck Tank 880 Gal N/A N/A Single WallCommunications 32 Gal 0.4 Gal/Hr 80 Hrs Single WallTrailer (COW)Light Plant #1 30 Gal 0.3 Gal/Hr > 3 days Single WallLight Plant #2 30 Gal 0.3 Gal/Hr > 3 days Single Wall* Diesel Driven Fire Pump is bounded by the operation of the BDB High Capacitypump.** Optional-Not FLEX credited equipment.

Estimated from run time specification.

Page 32 of 54 Serial No. 14-394ADocket No. 50-339Order EA-1 2-049Attachment 2ISE CI 3.4.AConfirm the implementation of considerations 2 through 10 in NEI 12-06, Section 12.2.Dominion

Response

Considerations 2 through 10 in Section 12.2 of NEI 12-06 are, in general, considerations applicable to the third party organization handling the Phase 3 portion of the FLEXMitigating Strategies.

This organization, SAFER, has prepared a White Paper addressing these 9 considerations.

This White Paper was formally transmit to the NRC forendorsement on September 11, 2014, (ADAMS Accession No. ML14259A222),

andendorsed by the NRC by letter dated September 26, 2014 (ADAMS Accession No.ML14265A107).

Page 33 of 54 Serial No. 14-394ADocket No. 50-339Order EA-1 2-049Attachment 2Licensee Identified 01 10The Dominion Nuclear Training Program will be revised to assure personnel proficiency inthe mitigation of BDB events is developed and maintained.

These programs and controlswill be developed and implemented in accordance with the Systematic Approach toTraining (SAT).Dominion

Response

FLEX Support Guidelines (FSGs) have been developed to provide guidance to Operations personnel for implementing new FLEX strategies and operating new FLEX equipment necessary to mitigate the consequences of beyond-design-basis external events (BDBEE).Dominion Nuclear Training used the SAT process to review the draft FSGs and identified that there were new tasks that were required to be performed by operations personnel.

Consequently, the SAT process was used to perform a Job Analysis of these newoperational tasks utilizing the FSGs.The results of the Job Analysis for the new operational tasks were presented andapproved by the Operations Curriculum Review Committee.

The new operational taskshave been integrated into the Initial and Continuing Operations Training Programs.

Forexample, the Nuclear Control Room Operator Development Program (NCRODP)

ProgramGuide has been updated to include the new tasks.The completed Job Analysis Worksheets and a copy the NCRODP Program Guide havepreviously been provided to the NRC staff and are available for their review.Page 34 of 54 Serial No. 14-394ADocket No. 50-339Order EA-1 2-049Attachment 2Licensee Identified 0111Complete the evaluation of TDAFW pump long term operation with < 290 psig inletsteam pressure.

Dominion

Response

TDAFW pump operation and adequate AFW flow to the steam generators (SGs) at SGpressures

< 290 psig has been confirmed by Calculation ME-0968, Revision 0,"Evaluation of the TDAFW Pump Performance at Low Steam Generator Pressures,"

August 2013. A copy of Calculation ME-0968, Revision 0 has previously been providedto the NRC staff and is available for their review.Page 35 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2Licensee Identified 0112Plant modifications will be completed for permanent plant changes required forimplementation of FLEX strategies.

Dominion

Response

The plant modification design changes (DCs) implemented in support of the FLEXstrategies for Unit 2 compliance, including Spent Fuel Pool Level Instrumentation, areas follows:Unit 2 Modifications:

FLEX Mechanical Connections (NA-12-00066),

FLEX Electrical Connections (NA-13-01018),

Quench Spray (QS) Piping Connection (NA-13-00081),

Primary Grade Water Tank Mechanical Connection (NA-13-00084),

Power Feeds toSupport Pre-Stage 120VAC Generators (NA-13-00088),

and Condenser HotwellConnections (NA-14-00035).

Modifications common to both Units 1 and 2: Spent Fuel Pool Mechanical Connections (NA-12-01218),

Alternate RCS Injection Connection (NA-13-00085),

Alternate Auxiliary Feedwater (AFW) Connection (NA-13-00083),

Service Water Mechanical Connection (NA-13-00090),

Concrete Pads and Grounding Connection for Pump Draft Locations (NA-14-00027),

BDB Storage Building (NA-13-00061),

BDB Offsite Communications (NA-14-01077),

and Spent Fuel Pool Level Instrumentation (NA-13-01043).

Copies of these DCs have previously been provided to the NRC staff and are available for their review.Page 36 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2Safety Evaluation item 1Feb 2014 Update Section 4a. Portable 120/240VAC DG will now be pre-staged.

Dominion

Response

Attachment 1, Item 4a, of the Six Month Status Update letter dated February 27, 2014[ML14069A009]

revised the strategy for repowering key instrumentation by pre-staging the BDB portable 120/240 VAC diesel generator.

This strategy change was notrequired, but was proposed to facilitate the connection of the 120/240 VAC generators in a timely manner. Since the pre-staged 120/240 VAC generators were not fullyprotected against BDB External Event hazards, it has always been the case that eitherthe backup 120/240 VAC generator or the alternate 480 VAC generator were available in the protected BDB Storage Building and were capable of being deployed andconnected prior to the depletion of the station batteries at 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months following the onset ofthe ELAP event.However, it was recently determined that pre-staging the generators in the alleyways adjacent to the Units 1 and 2 Service Buildings resulted in a fire safety issue due to theconcern that the generator would contain approximately 100 gallons of diesel fuel andcould not be positioned to meet the required safe distance requirements applicable atNorth Anna.Therefore, the re-powering strategy using the 120/240 VAC diesel generators hasreverted back to the original proposed strategy presented in the February 2013 0IP.Specifically, the 120/240 VAC diesel generators will be stored in the BDB StorageBuilding and are capable of being deployed and connected prior to the depletion of thestation batteries at 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months following the onset of the ELAP event.Additionally, the North Anna Onsite Audit Report, Attachment 5, requested Dominion to:"Provide time validation study results confirming equipment can be deployed, staged,connected to the electrical distribution system, and supply power to the loads within thetimes assumed in the licensee's overall integrated plan." This NRC request isaddressed as follows:The time validation for transporting and setting up the 120/240 VAC Diesel Generators (DGs) has been completed for North Anna and is documented in ETE-CPR-2014-1004, "North Anna Power Station Beyond Design Basis FLEX Validation for Time Sensitive Actions (TSA's)."

As documented in the validation ETE, the time to transport and placethe generators was validated separately from the connection and startup of the DG.Validation was performed for both units and was assumed to start 3 hours3.472222e-5 days 8.333333e-4 hours 4.960317e-6 weeks 1.1415e-6 months following theELAP. This includes the 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months delay for declaration of the ELAP and a 2 hour2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months periodfor debris removal.Page 37 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2The transport time assumed travel from the station to the BDB Storage Building, theconnection of the DG to the tow vehicle, transport of the DG to its deployment

location, and placement of the DG at the deployment location.

The resulting validation timeswere 0.7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months and 0.75 hours8.680556e-4 days 0.0208 hours 1.240079e-4 weeks 2.85375e-5 months for Units 1 and 2, respectively.

The connection/setup validation included routing and connection of the 120 VAC cablesand simulation of the DG startup per FSG-4, Attachments 4 and 5. Again, both unitswere validated separately with the results being 0.75 hour8.680556e-4 days 0.0208 hours 1.240079e-4 weeks 2.85375e-5 months and 0.9 hours1.041667e-4 days 0.0025 hours 1.488095e-5 weeks 3.4245e-6 months for Units 1 and2, respectively.

The connection/setup for the first DG would begin following completion of itsdeployment and coincident with the transport and placement of the second generator.

Considering the longest transportation time (0.75 hours8.680556e-4 days 0.0208 hours 1.240079e-4 weeks 2.85375e-5 months ) and the longestconnection/setup time (0.9) hours, the time required to deploy and connect both the Unit1 and 2 120 VAC DGs would be approximately 2.40 hours4.62963e-4 days 0.0111 hours 6.613757e-5 weeks 1.522e-5 months .These times, combined with the initial 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months delay prior to the declaration of an ELAPand the two hour debris removal period, demonstrate DG availability for both units canbe achieved in less than 5.5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months providing a minimum 2.5 hour5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months margin until depletion of the station batteries.

FSG-4 and a copy of ETE-CPR-2014-1004 have previously been provided to the NRCstaff and are available for their review.Page 38 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2Safety Evaluation Item 42. (Westinghouse Standard RCP Seals: NSAL-14-1)

On February 10, 2014,Westinghouse issued Nuclear Safety Advisory Letter (NSAL)-14-1, which informedlicensees of plants with standard Westinghouse RCP seals that 21 gpm may not bea conservative leakage rate for ELAP analysis.

This value had been previously usedin the ELAP analysis referenced by many Westinghouse PWRs, including thegeneric reference analysis in WCAP-17601-P.

Therefore, please clarify whether theassumption of 21 gpm of seal leakage per RCP (at 550 degrees F, 2250 psia)remains valid in light of the issues identified in NSAL-14-1.

In so doing, pleaseidentify the specifics of the seal leak off line design and #1 seal faceplate materialrelative to the categories in NSAL-14-1 and identify the corresponding presumedleakage rate from NSAL-14-1 that is deemed applicable.

Dominion

Response

Westinghouse issued a Nuclear Safety Advisory Letter, NSAL-14-1, which concluded that based on Westinghouse RCP Seal leakoff line configuration, the previously assumed value of 21 gpm following a loss of seal cooling event could be non-conservative.

The NSAL determined that for four potential seal configuration casesbased on seal type, seal leakoff line piping size and length, and flow orifice size, theseal leakage rates vary. Based on a review of North Anna's seal leakoff configuration, the NSAL Case 2 represents the NAPS RCP seal design for those pumps withWestinghouse seals (i.e., No. 1 seal faceplate material made from Silicon Nitride(Si3N4), greater than 3/4" leakoff lines, and a 3/8" diameter flow orifice).

The estimated leakage from this configuration per the NSAL is 24 gpm, which is greater than the 21gpm currently assumed in the reference analysis.

For Unit 2, 2 of 3 Westinghouse RCPseals have been replaced with the Flowserve N-9000 low leakage seals. By the fullcompliance date for Unit 1 (4/1/15),

at least 2 of the 3 Westinghouse RCP seals willhave been replaced with Flowserve N-9000 low leakage seals. Therefore, the expectedmaximum RCP seal leakages would also be around 65% of the value assumed in thereference analysis.

Maximum total RCP seal leakage (all three pumps) is therefore expected to be around 65% of the value assumed in the reference analysis.

These sealconfigurations account for the increased potential leakage in the remaining Westinghouse seal identified in NSAL-14-1.

Therefore, the assumptions for the totalRCP seal leakage rate in the analysis remain bounding for NAPS Units 1 and 2.In response to NSAL 14-1, the Pressurized Water reactor Owner's Group (PWROG)has documented leakage rates for Westinghouse RCP Original Equipment Manufacturer Seals in PWROG-14015, Revision

1. The initial leakage information consisted of three points: initial leakage at normal operating temperature and normaloperating pressure (NOT/NOP);

peak leakage at 1500 psia; and leakage at the cooled-down, depressurized conditions.

Additional studies have been completed thatdemonstrate the reasonableness of the linear assumptions between points, the peakleakage, and the effect of minimal subcooling.

Page 39 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2Leakage values have been incorporated in ETE-NAF-2012-0150, Revision 2 thatcalculates the estimated time for the onset of reflux cooling in order to validate the timeRCS makeup should be initiated for North Anna Units 1 and 2. The estimated time toreach reflux cooling for Unit 2 is 17.6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months . The margin to the established time of 16hours for the implementation of the RCS makeup is 1.6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months for Unit 2 with twoFlowserve seals.Copies of PWROG-14015, Revision 1 and ETE-NAF-2012-0150, Revision 2 havepreviously been provided to the NRC staff and are available for their review.Safety Evaluation Item 8Please provide adequate basis that, when considering mixing time, there is sufficient flow capacity to support borated makeup to both units from a single RCS makeup pumptaking suction from a portable batching tank.Dominion

Response

The ability to provide makeup to the RCS of both units using a single RCS Injection pump in conjunction with the on-site portable BDB Boric Acid Mixing Tanks (BAMTs) isa viable strategy with a reasonable amount of margin (>15%). The entry conditions ofthis scenario are that both RWSTs are unavailable, only one RCS injection pump isavailable, and both portable BAMTs from the BDB Storage Building are available.

Ifone of the two BDB RCS Injection Pumps stored in the on-site BDB Storage Building isinoperable, the single operable RCS Injection pump may be used to supply RCSinventory makeup to both units by alternating RCS injection between the units. In thisconfiguration, the RCS Injection pump would discharge to the alternate RCS Injection connection located in the Hydrogen Recombiner Vault so that the single pump cansupply borated water to either unit through valve manipulation of the charging systemcross-tie piping.Flow is alternated between Unit 1 and Unit 2 by manually operating the normal chargingheaders cross-tie valves. Components in this CVCS flow path are Safety Related,seismically constructed/mounted and located in missile protected facilities.

Oncealigned, the transfer of flow from one unit to the other is controlled by two manualvalves, one for each unit. Based on the location of the valves, it is reasonable toassume that the transfer of flow can be achieved within a 5 minute period. Flow to theRCS will be through the Cold Leg injection path via the Boron Injection Tanks (BIT's).The borated water supply for the RCS Injection Pump would be the 1,000 gallonportable BAMTs deployed from the BDB Storage Building.

The two portable BAMTs willbe transported from the BDB Storage Building and positioned next to the BDB RCSInjection pump. Bags of boric acid crystals can be added to the portable BAMTs andPage 40 of 54 Serial No. 14-394ADocket No. 50-339Order EA-1 2-049Attachment 2mixed with dilution water from the BDB AFW pump or from the BDB High Capacitypump. Each 1,000 gallon batch of borated water would use 2/2 50 lb bags of dry boricacid to provide a boron concentration comparable to the RWST boron concentration of2,600 ppm. The dry boric acid is added to a basket strainer at the top of the tank whichenhances the dispersion of dry boric acid into the tanks. Dilution water to the BAMTswill be from one of the following

sources, based on operating staff evaluation ofavailability and any competing demands (e.g., addition to the steam generators or spentfuel pool) and in the order of priority as listed:-The Emergency or Main Condensate Storage Tanks (ECST / CST)-The Primary Grade Water Storage Tanks 1-PG-TK-1A/1-PG-TK-1B

-The Condenser Hotwell 1/2-CN-SC-1A/B

-Lake Anna-Fire Protection

-Service WaterUsing the BDB AFW Pump (or the BDB High Capacity Pump), the fill time for a portableBAMT is less than 10 minutes (51,000 gallons at >100 gpm). Mixing is performed usinga mechanical agitator (one available for each tank) powered by a portable 120 VACgenerator.

Mechanical agitation will prevent settling of undissolved acid particles belowthe tank outlet, therefore, complete dissolution of the acid in the tank is not necessary.

Assuming a 15 minute mixing time, the complete cycle to prepare a 1,000 gallon batchof borated water with a concentration greater than the RWST is approximately 25minutes (<10 minutes fill and 15 minutes mixing).It is assumed only 90% of the BAMT volume is injected with each injection cycle.Injecting 900 gallons of borated water into the RCS at a rate of 45 gpm with the RCSInjection pump will take 20 minutes.

The time remaining until the next batch is available (using the other tank and a 25 minute batch cycle) is 5 minutes.

As previously stated,this is more than adequate time to re-align the two valves necessary to swap theinjection feed to the opposite unit. Therefore, it is reasonable to credit 900 gallons ofborated water makeup to each RCS every 50 minutes.It is conservatively assumed that the borated water temperature in the BAMT is 900F.At this temperature, the amount of borated water injected into the RCS over a 50 minuteperiod is 7,474 Ibm. If the loss of RCS inventory due to seal leakage is less than 7,474Ibm, then the RCS inventory will be increasing.

The following is an assessment of the RCS inventory loss due to seal leakage assumingthe most conservative RCP seal configuration for North Anna which consists of 1Westinghouse seal and 2 Flowserve seals for Unit 2. RCS makeup will commence nolater than 16 hours1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months after the onset of the ELAP event. This is well after the RCScooldown and depressurization has been performed in accordance with ECA-0.0, whichstarts at 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months and will be take approximately 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months to complete.

Therefore, RCPseal leakage at the initiation of the RCS makeup activity will be significantly reducedPage 41 of 54 Serial No. 14-394ADocket No. 50-339Order EA-1 2-049Attachment 2below its initial value. Based on conservative RCP seal leakage rates for a configuration of 1 Westinghouse seal and 2 Flowserve seals and the inclusion of a 1 gpm unidentified leakage rate, a total RCS leakage rate of 2.15 Ibm/sec is assumed.

This corresponds toa 6,450 Ibm reduction of RCS inventory over a 50 min period from RCP seal leakageand unidentified leakage.

As stated above, 900 gallons of borated water from theBAMT corresponds to approximately 7,476 Ibm of RCS inventory makeup. Thismakeup mass is -15% greater than the mass lost due to RCP seal leakage.

Therefore, based on the most limiting configuration of installed seals, conservative RCP seal leakrates, and the time necessary to prepare and inject batches of borated water using theportable BAMTs, the RCS inventory for Unit 2 would be increasing at a rate ofapproximately 1,026 Ibm every 50 minute period or an average of 1,230 Ibm/hr.The NRC requested Dominion to "evaluate the case when both units achieve fullcompliance in Spring 2015 using the latest seal leakage values."

In this configuration, the Unit 2 seals would be as discussed above and the expected Unit 1 sealconfiguration would consist of 3 Flowserve seals. Calculation MISC-1 1788, AddendumB, "Investigation of Reactivity Control During Extended Station Blackout, North AnnaUnits 1 and 2 -Boric Acid Mixing/Batching Operations,"

examines the timing of mixingand batching of boric acid to support RCS injection during an ELAP with both NorthAnna units in full compliance status.The leakage from the Unit 1 Flowserve seals (and 1 gpm of unidentified leakage) wouldbe less than half of the evaluated Unit 2 seal leakage.

The makeup mass from theBAMT is that same for both units; therefore, the RCS inventory for Unit 1 would beincreasing at an average rate greater than twice that of Unit 2. In the event Unit 1 onlyreplaces 1 Westinghouse RCP seal; then the Unit 1 configuration would be the same asthe current Unit 2 configuration.

This Unit 1 seal configuration (like Unit 2) would beacceptable for compliance with regards to maintaining sufficient flow capacity to supportborated makeup to both units.The following conclusions are drawn:1. For the worst-case scenario of no RWST's and only 1 BDB RCS injection pumpavailable, it is possible to batch and mix two portable tanks and inject them in amanner that keeps up with worst-case reactor coolant pump seal leakage in bothunits.2. The time available to perform the operations is adequate.

There is -15% marginbetween integrated makeup and leakage for the highest leakage configuration (1Westinghouse and 2 Flowserve seals) and -145% margin on the lowest leakageconfiguration (all Flowserve seals).3. The exact strategy, timing and sequencing of injection between units woulddepend on RCS leakage trends, which can be estimated by the operators usingPage 42 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2available pressurizer and RVLIS level indications, as well as an assessment ofavailable equipment.

Calculation MISC-1 1788, Addendum B, has previously been provided to the NRC staffand is available for their review.Page 43 of 54 Serial No. 14-394ADocket No. 50-339Order EA-1 2-049Attachment 2Safety Evaluation item 11Unprotected water sources in Modes 5 & 6Dominion

Response

North Anna Power Station will abide by the Nuclear Energy Institute position paperentitled "Shutdown

/ Refueling Modes" addressing mitigating strategies in shutdown andrefueling modes that is dated September 18, 2013 and has been endorsed by the NRCstaff. The primary source of borated water for injection into the RCS is the RWST.Although, the RWSTs are not missile protected, credit as a borated water source wasbased on the assumption that it was improbable that both tanks would be destroyed bya single tornado.

Subsequently, the strategy has been revised to address the scenariowhere both RWSTs are unavailable.

The revised strategy includes the provision toutilize other non-borated onsite water sources with priority given to the highest qualitysources first, as available.

The prioritization of these non-borated sources is given inSection 2.2.1 of ETE-CRP-2012-0012, Revision

5. The constraint with this approach isthat flow must be controlled in order to match the rate of water loss (due to boiling) sothat dilution of the boron concentration in the RCS does not occur.Guidance to prevent dilution of the boron concentration during RCS makeup in Modes 5and 6 is contained in FSG-14. This FSG includes a prioritized list of water sources forRCS makeup water to the core. If a borated source is used, the RCS makeup flow ratemust be equal to or greater than the minimum injection flow identified in the curveprovided in Attachment 9 of FSG-14, Minimum RCS Flow Rate vs. Time After Trip. If anon-borated source is used, FSG-14 includes guidance that the RCS makeup flow ratemust equal the minimum flow shown in the curve provided in Attachment 9.Copies of ETE-CRP-2012-0012, Revision 5 and FSG-14 have previously been providedto the NRC staff and are available for their review.Page 44 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2Safety Evaluation Item 12FLEX 120/480 VAC cable storage,

testing, and maintenance.

Dominion

Response

Details on maintenance and testing and storage of 120v/240v pre-staged cables andthe 480v cables stored in the BDB Storage Building are provided below.Both the 120v/240v and 480v cables are inspected and tested on initial receipt.

Thisincludes:

-Visual inspection for damage or breakdown.

-Inspection of cord ends to ensure supplied dust caps are snug and in place andthere is no internal damage.-Performance of OHM measurement (continuity check) of each conductor.

-Performance of megger check between each current carrying conductor and theconductor to ground.The 120v/240v pre-staged power cables will be stored on cable reels located in theHydrogen Recombiner Control Panel Vault. Additional (spare) cables will be stored inthe BDB Storage Building.

Periodic Maintenance procedures for BDB FLEX equipment have been reviewedagainst existing EPRI Templates in accordance with the Dominion Equipment Reliability Process.

When the new EPRI template for the RCS injection pumps is issued, theguidance in the template will be reviewed and taken into consideration for incorporation.

In Attachment 5 of the North Anna Onsite Audit Report, the NRCstaff requested Dominion to provide additional input regarding the following:

"The staff expects someperiodic maintenance will be performed to uncover any degradation over time. Alsoaddress how the cables will be stored to prevent any damage as a result of anearthquake (i.e., anchored/secured to the floor or wall within a seismically protected structure)."

Based on the request for additional input, Dominion has revised the FLEX 120/240 VACand 480 VAC Cables Fleet Template and Maintenance Strategies to include a periodicvisual/tactile inspection for evaluating cable system component aging and a continuity test in addition to the visual inspection on the molded ends of the cable to ensure theirreliability.

The cable storage location is the Hydrogen Recombiner Control Panel Vault area in theUnit 2 Alleyway.

This location is missile protected with the exception of the accessdoor. This is acceptable since the cables are staged away from the door and theoutside is not visible from the storage location.

The cables are stored on K-Kart cablereels. There is no seismic sensitive equipment in the area where the cable carts arePage 45 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2located.

It should be noted that the cable carts are designed to be tip-proof.

This tip-proof design further prevents the possibility of any damage to the carts or surrounding equipment during a seismic event. The ratio of the cable cart height to the smallestbase is less than two, and thus the carts will remain stable during a seismic event. Thecarts do have two wheels in the back to make them carts and are thereby classified as amobile stable commodity.

The front of the cart consists of a flat plate or foot, whichcreates a high friction contact area that prevents the cart from rolling.

The carts areconfigured in a row, front to back, with the wheels of the last cart chocked.

Storage ofthe cable carts in this configuration will avoid movement during a seismic event;therefore, preventing the possibility of any damage to the carts or surrounding equipment.

Page 46 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2Safety Evaluation Item 16Please provide adequate justification for the seal leakage rates calculated according tothe Westinghouse seal leakage model that was revised following the issuance of NSAL-14-1. The justification should include a discussion of the following factors:a. benchmarking of the seal leakage model against relevant data from tests oroperating events,b. discussion of the impact on the seal leakage rate due to fluid temperatures greater than 550°F resulting in increased deflection at the seal interface,

c. clarification whether the second-stage reactor coolant pump seal would remainclosed under ELAP conditions predicted by the revised seal leakage model and atechnical basis to support the determination, and,d. justification that the interpolation scheme used to compute the integrated leakagefrom the reactor coolant pump seals from a limited number of computer simulations (e.g., three) is realistic or conservative.

Dominion

Response

16a) The PWROG is performing a benchmark of the EDF 7" seal. Testing of the EDF7" seal occurred in the mid-1980's.

WCAP-10541, Revision 2 includes a summary of thetest. The benchmark will use the analysis methodology described in the response toItem 16b below.WCAP-10541, Revision 2 documented the No. 1 seal leakage rates of an 8"Westinghouse reactor coolant pumps (RCP) following a loss of all Alternating Current(AC) power for a reference case. MPR Associates was contracted by Westinghouse toperform independent calculations of RCP seal leakage, the results of which areprovided in MPR-797.

In addition, the NRC contracted with Energy Technology Engineering Center (ETEC) to perform an independent investigation of the seal leakagerates for Westinghouse RCPs following a loss of all seal cooling.

The ETEC work issummarized in WCAP-10541, Revision

2. These analyses used the same overallmethodology which is summarized in the response to Item 16b below. The seal flowrate predicted by ETEC at low RCS pressure is approximately one-half of that predicted by Westinghouse.

The estimated times to reach reflux cooling for the North Anna units is 17.6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months whichprovides a margin to the established time of 16 hours1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months for the implementation of the RCSmakeup of 1.6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months . This margin is judged to be sufficient based on the comparison ofthe independent evaluations of the RCP leakage in WCAP-10541, Revision

2. This willbe confirmed by the benchmark analysis.

16b) PWROG-14013, Revision 1 "Summary of Validation of Seal Flow Calculations atReduced Reactor Coolant System Pressures Report,"

provides a description of theoverall analysis methodology which is summarized in Section 2.4 as follows:Page 47 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2-Determination of seal deformation due to pressure and temperature gradients using a finite element evaluation,

-Determination of seal flow and seal gap as a function of seal inlet and outletpressures based on assumed seal gap, and-Determination of seal outlet pressure due to No. 1 seal leak-off line pressure drop.Westinghouse performed a finite element evaluation to determine the effect of pressureand temperature boundary conditions on the mechanical deformation of the No. 1 seal.The Westinghouse seal flow rates provided in PWROG-14015, Revision 2, used theITCHSEAL code to determine the seal flow rate. The ITCHSEAL code is a merger oftwo programs:

the ITCH program, which is used to model general thermal hydraulic transients, and the SEAL program, which solves the hydraulic and force balances forthe film riding seals. The ITCHSEAL code uses the results of the finite element analysisas input.Therefore, the impact on the seal leakage rate due to fluid temperatures greater than550°F (increased deflection) has been incorporated into the ITCHSEAL analyses.

Theresults of these calculations are documented in PWROG-14015, Revision 2.16c) Section 3.1.1 of PWROG-14017, Revision 1, provides a discussion of theevaluation of the No. 2 seal performance from WCAP-10541, Revision

2. Section 4.3 ofWCAP-10541, Revision 2, states that Westinghouse performed thermal-hydraulic andmechanical finite element analysis for the pressure and temperature conditions on theNo. 2 seal ring and runner assemblies similar to the No. 1 seal described in Section 4.1of WCAP-10541.

The analysis indicates that the converging film induced in the No. 2seal by pressure forces, causing mechanical face rotation, is reversed by the largethermal gradient the phase change in the No. 2 leak-off in situations where the No. 1seal remains functional.

Further, it is stated that the thermal face rotation is more thanan order of magnitude greater than the pressure induced deflection.

Testing of the 7"EDF seal was discussed in Section 7 of WCAP-10541.

Therein, it is stated that the No.2 seal established the thermal gradients and pressure loadings which forced the sealfaces to be diverging resulting in the closure of the No. 2 seal in the manner predicted by the analysis of the 8-inch standard and 8-inch cartridge seal. Therefore, it wasconcluded that the No. 2 seal is considered to be functioning, but is modeled as a tightlyclosed obstruction which does not allow flow to pass.16d) The PWROG has documented leakage rates for Westinghouse RCP OriginalEquipment Manufacturer (OEM) Seals in PWROG-14015, Revision 2 using boundingplant configurations.

The initial leakage information consisted of three points: initialleakage at normal operating temperature and normal operating pressure (NOT/NOP);

peak leakage at 1500 psia; and leakage at the cooled-down, depressurized conditions.

Additional studies have been documented in PWROG-14015, Revision 2 to evaluate thelinear assumptions between points and the effect of minimal subcooling for Category 1seals. The intermediate flow rates are slightly above what is predicted by the linearPage 48 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2assumption for seal leakage between the Revision 0 points. The seal leakage flow rateis almost unaffected from the change from 5°F of sub-cooling to less than IVF of sub-cooling.

For each pressure

analyzed, these points are within 0.1 gpm. PWROG-14015, Revision 2 transmits the results of the calculation of the seal flow rate for each categoryof plant identified in PWROG-14008, Revision

1. Westinghouse has performed sufficient calculations to confirm the reasonableness of linear interpolation between points, thatthe peak leakage occurs at 1,500 psia, and to include minimal subcooling.

Page 49 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2Safety Evaluation item 17The NRC staff understands that Westinghouse has recently recalculated seal leakoffline pressures under loss of seal cooling events based on a revised seal leakage modeland additional design-specific information for certain plants.a. Please clarify whether the piping and all components (e.g., flow elements, flanges,valves, etc.) in your seal leakoff line are capable of withstanding the pressurepredicted during an ELAP event according to the revised seal leakage model.b. Please clarify whether operator actions are credited with isolating low-pressure portions of the seal leakoff line, and if so, please explain how these actions will beexecuted under ELAP conditions.

c. If overpressurization of piping or components could occur under ELAP conditions, please discuss any planned modifications to the seal leakoff piping and component design and the associated completion timeline.

d. Alternately, please identify the seal leakoff piping or components that would besusceptible to overpressurization under ELAP conditions, clarify their locations, andprovide justification that the seal leakage rate would remain in an acceptable range ifthe affected piping or components were to rupture.Dominion

Response

PWROG-14008-P, Revision 2, "No. 1 Seal Flow Rate for Westinghouse ReactorCoolant Pumps Following Loss of All AC Power, Task 1: Documentation of PlantConfigurations" (September 2014) defines North Anna as a "Category 3" plant relativeto PWROG-14015-P.

PWROG-14015-P, Revision 0, "No. 1 Seal Flow Rate forWestinghouse Reactor Coolant Pumps Following Loss of All AC Power, Task 2:Determine Seal Flow Rates" (June 2014) defines a Category 3 plant as a plant with amaximum 2,250 psia operating pressure at the pump/seal connection and 224 psia (209psig) downstream of the seal leakoff line flow elements.

The Westinghouse analysisassumes the seal leakoff line relief valve is lifting at its set point of 150 psig and thepiping downstream of the flow element pressurizes above the set point due to flowresistance from the flow elements to the relief valve.a. The Westinghouse analysis assumptions for line size for determining themaximum operating pressure downstream of the flow elements are conservative relative to the NAPS seal leakoff line configuration.

Specifically, theWestinghouse analysis conservatively assumes a 1.5" diameter for thedownstream piping. The majority of the piping and piping components (fittingand valves) downstream of the flow element at NAPS is 2" and 3" diameter Class153A (TP304SS)

Sch. 40S piping, however, NAPS does have a relatively smallamount of 3/4" piping (both Class 1502 and Class 153A) immediately downstream of the flow elements.

The Class 1502 3/4" piping and associated isolation valvesis 1,500 psig class piping. All of the Class 153A (TP304SS)

Sch. 40S piping andfittings have maximum working pressures greater than 1500 psig at temperatures up to 6000F. The only components in the system that are rated below 1500 psigPage 50 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2are the Class 153A valves. However, all of these valves are located downstream of the seal leakoff line relief valve and would not be subject to pressures inexcess of 150 psig (RV setpoint).

Therefore, Dominion does not anticipate thecomponents downstream of the flow elements to be in danger of failure at theconservative Westinghouse analysis maximum pressure downstream pipingconditions.

b. Operator actions are not taken to isolate the Class 153A (TP304SS) sections ofseal leakoff line piping for RCPs with Westinghouse seals. Per ECA-0.0,Operator actions are taken to isolate the Class 153A sections of the seal leakoffline piping for RCPs with Flowserve seals. However, during an ELAP, theContainment Instrument Air system is not credited and, therefore, isolation of theseal leakoff lines for RCPs with Flowserve seals is not assumed.c. No modifications to the piping configuration are planned for the Class 153Asections of seal leakoff line piping.d. No components in the seal leakoff lines between the pressure reducing flowelement and the relief valve are susceptible to over-pressurization under ELAPconditions.

Page 51 of 54 4Serial No. 14-394ADocket No. 50-339Order EA-1 2-049Attachment 2Audit Question 44Provide a detailed discussion on the loads that will be shed from the dc bus, theequipment location (or location where the required action needs to be taken), and therequired operator actions needed to be performed and the time to complete each action.In your response, explain which functions are lost as a result of shedding each load anddiscuss any impact on defense in depth and redundancy.

Dominion

Response

There are four (4) 125 VDC buses per unit at North Anna. The four DC bus distribution panels per unit are located in the Emergency Switchgear Room (ESGR) at elevation 254', directly below the Main Control Room (MCR) at elevation 274'. The ESGR hasmultiple access points including the stairwell behind the MCR, two access points fromelevation 254' in the Turbine Building, and the Control Rod Drive Room. The ESGR is apart of the MCR pressure envelope and is in a Category 1 turbine-missile and floodprotected room. Multiple access points provide reasonable assurance that the 125 VDCpanels will remain accessible during any BDB ELAP scenario.

Upon declaration of an ELAP, an operator will be dispatched from the MCR to performDC Bus load stripping per the guidance in FLEX Support Guideline, 1/2-FSG-4, "ELAPDC Bus Load Shed and Management."

Within 60 minutes following the onset of anELAP event, 1/2-ECA-0.0 instructs the operator to secure the DC Seal Oil Pump andDC Turbine Oil Pump after ensuring the hydrogen gas has been vented from the MainGenerators.

After declaration of an ELAP event (at 60 minutes),

the operator will thenstrip the remaining DC loads from the DC buses and the AC loads from the vital buseswithin the following 30 minutes.

Therefore, all load stripping will be completed within 90minutes following initiation of the ELAP event.The four (4) DC buses per unit each provide power to their respective vital businverters, which convert 125 VDC to 120 VAC. All loads are stripped from the DCbusses with the exception of these vital bus inverters.

Load stripping in FSG-4 alsoincludes the guidance to strip selected 120 VAC vital bus loads to preserve theemergency batteries.

The required actions to strip the 120 VAC loads from the ACbuses are performed in the Hathaway and Computer Rooms, which are an extension ofthe Main Control Room, elevation 274'. The DC bus loads and the 120 VAC vital busloads that are being stripped are identified in Tables provided in Section 19.1 (Appendix 7A) of ETE-CPR-2012-0012, Revision

5. These tables provide a detailed description ofthe vital bus AC loads and the DC loads that are being stripped and the basis forstripping the load. The tables are provided for Unit 1 only, but are typical for Unit 2.Per NEI 12-06, Section 3.2.1.3(9),

FLEX strategies do not need to assume additional failures beyond those attributed to the BDB External Event directly.

Therefore, instrumentation redundancy is not a requirement for the key parameter indications which remain available after load stripping has been performed.

However, as a defensePage 52 of 54 I-Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2in depth approach, alternate indications are available from an independent sources,such as a local pressure gauge, level versus flow indication, etc., for many of the NorthAnna key parameters identified in the Overall Integrated Plan. Tables 7.1.1.1 thru7.1.1.4 in ETE-CPR-2012-0012, Revision 5 address this alternate indication.

During the May 2014 NRC Onsite Audit, a question was received regarding clarification on the timing of the load stripping activities.

The response to that question is as follows:Calculation EE-0009, Rev 1, Addendum J, "125DC System Analysis,"

assumes the DCpowered Emergency Turbine Oil Pumps (ETOP) and the DC powered Air Side Seal OilBackup Pumps (ASSOBP) are secured at or prior to 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months ( T= 60 minutes) following aBDB External Event (BDBEE).

The shutdown of these two critical DC powered oilpumps is directed by Emergency Procedure 1/2-ECA-0.0 "Loss of All AC Power" at orPRIOR to T=60 minutes.

Specifically, Step 21 of ECA-0.0 provides direction to theControl Room Operator to shutdown these DC powered oil pumps. This action isaccomplished using control switches located on each units main control boards.Additionally, a "NOTE" prior to step 21 of ECA-0.0 has been upgraded to a "CAUTION" to warn the operator that "Operation of the DC powered Turbine Oil Pumps and DCpowered Air Side Seal Oil Pumps for more than 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months with the Battery Chargers out ofservice significantly reduces remaining battery capacity."

Calculation EE-0009, Rev 1, Addendum J, further assumes the remaining non-critical DC and Vital AC loads are stripped PRIOR to T=90 Minutes following a BDBEE. ECA-0.0 directs the operators to restore AC power within 60 minutes OR declare anExtended Loss of All AC Power (ELAP) event has occurred and initiate FLEX StrategyGuideline 1/2-FSG-4 "ELAP DC Bus Load Shed / Management."

If the ELAP event isdeclared at T= 60 minutes the operators have 30 minutes to complete the load stripping of the remaining non-critical DC and Vital AC loads per the guidance provided in 1/2-FSG-4.A tabletop review for the load stripping activity assumed 10 minutes would pass from anELAP declaration to the time when operators would begin to execute load stripping inaccordance with the attachments for load shedding in FSG-4. A time of 15 minutes wasconsidered reasonable for the completion of each attachment that accomplished aportion of the load shedding.

There are a total of four attachments (two for each unit)needed to perform the load shedding.

1/2-FSG-4 directs the load shedding attachments to be performed simultaneously by two operators per unit (total of four operators) toensure that BDB response times are met. These four operators are included in theminimum staffing requirements.

An actual timed walk down of the two Unit 2 attachments (which have more actions thanthe Unit 1 attachments) was performed from the direction point (Control Room) until theattachments were completed utilizing all safety precautions, PPE and HumanPerformance tools. These Unit 2 attachments were executed in six and seven minuteseach which was considerably less than the assumed time of 15 minutes per attachment.

Page 53 of 54 Serial No. 14-394ADocket No. 50-339Order EA-12-049 Attachment 2This timed walkdown executed the Unit 2 attachments one after the other, however, perthe direction in 1/2-FSG-4, the attachments would be executed simultaneously.

Whenadded to the delay time of 10 minutes after an ELAP is declared, the simultaneous execution of the four load stripping attachments is easily less than the 30 minutesassumed in the battery life calculations.

The load stripping of non-critical DC and Vital AC loads within 30 minutes is considered an Operator Time Sensitive Action and has been identified as such in Table 9.1-1 ofETE-CPR-2012-0012, Revision 5.The North Anna Onsite Audit Report, Attachment 5, requested Dominion to: "Provideformal results of the time validation of dc load shedding."

The response to this requestis as follows:The time validation of the DC and Vital AC load stripping activities was completed forNorth Anna and is documented in ETE-CPR-2014-1004, "North Anna Power StationBeyond Design Basis FLEX Validation for Time Sensitive Actions (TSA's),"

Aspreviously indicated, the load stripping activities are performed simultaneously usingfour separate operators, each with one of four separate load stripping attachments fromFSG-4.Copies of FSG-4, ETE-CPR-2012-1004, and ETE-CPR-2014-1004 have previously been provided to the NRC staff and are available for their review.Page 54 of 54

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