ML14069A009

North Anna, Units 1 & 2, six-month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation

ML14069A009
Person / Time
Site:	North Anna
Issue date:	02/27/2014
From:	Sartain M D Virginia Electric & Power Co (VEPCO)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
EA-12-051
Download: ML14069A009 (24)

Text

VIRGINIA ELECTRIC AND POWER COMPANYRICHMOND, VIRGINIA 23261 10 CFR 2.202EA-12-051 February 27, 2014Attention:

Document Control Desk Serial No.: 12-166EU.S. Nuclear Regulatory Commission NL&OS/MAE:

ROAWashington, D.C. 20555-0001 Docket Nos.: 50-338/339 License Nos.: NPF-4/7VIRGINIA ELECTRIC AND POWER COMPANYNORTH ANNA POWER STATION UNITS I AND 2SIX-MONTH STATUS REPORT IN RESPONSE TO MARCH 12, 2012 COMMISSION ORDER MODIFYING LICENSES WITH REGARD TO RELIABLE SPENT FUEL POOLINSTRUMENTATION (ORDER NUMBER EA-12-051)

References:

1. NRC Order Number EA-12-051, Order Modifying Licenses with Regard to ReliableSpent Fuel Pool Instrumentation, dated March 12, 20122. Virginia Electric and Power Company's Overall Integrated Plan in Response to March12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent FuelPool Instrumentation (Order Number EA-12-051),

dated February 28, 2013 (Serial No.12-166B)3. Virginia Electric and Power Company's Six-Month Status Report in Response to March12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent FuelPool Instrumentation (Order Number EA-12-051),

dated August 23, 2013 (Serial No. 12-166D)4. Virginia Electric and Power Company's March 12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051),

Request for Additional Information (RAI) Response, dated July 2, 2013 (SerialNo. 12-166C)5. North Anna Power Station, Units 1 and 2: NRC Interim Staff Evaluation and Request forAdditional Information Regarding to Overall Integrated Plan for Implementation of OrderEA-12-051, Reliable Spent Fuel Pool Instrumentation, dated November 1, 2013On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued an order (Reference 1)to Virginia Electric and Power Company (Dominion).

Reference 1 was immediately effective and directs Dominion to install reliable Spent Fuel Pool (SFP) Level Instrumentation.

Reference 1 required submission of an Overall Integrated Plan (OIP) (Reference

2) pursuantto Section IV, Condition C. Reference 1 also required submission of a status report at six-month intervals following submittal of the OIP.Attachment 1 of this letter provides the second six-month status report and an update ofmilestone accomplishments since the submittal of the first six-month status report (Reference 3), including any changes to the compliance method, schedule, or need for relief and the basis.On May 28, 2013, Dr. V. Sreenivas, the NRC Project Manager for North Anna Power Station,transmitted a Request for Additional Information (RAI) in an email to Mr. David Heacock,President and Chief Nuclear Officer of Dominion, regarding the North Anna SFP Level Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Page 2 of 3Instrumentation system OIP. By letter dated July 2, 2013, Dominion submitted its response tothe RAI (Reference 4).On November 1, 2013, Dominion received an Interim Staff Evaluation (ISE) regarding theNorth Anna SFP Level Instrumentation system OIP in a letter from Dr. V. Sreenivas to Mr.David Heacock (Reference 5). As discussed in a public meeting on February 6, 2014, with theNRC, the RAIs contained in the ISE supersede the May 28, 2013 RAts. Also, anycommitments made in Reference 4 are no longer applicable.

Responses to the RAIscontained in the ISE are provided in Attachment 2.If you have any questions, please contact Ms. Margaret Earle at (804) 273-2768.

Sincerely, Mark D. SartainVice President Nuclear Engineering Virginia Electric and Power CompanyAttachments (2)Commitments made by this letter: No new Regulatory Commitments COMMONWEALTH OF VIRGINIA)COUNTY OF HENRICOThe foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today by Mark D. Sartain who is Vice President Nuclear Engineering of Virginia Electric and Power Company.

Hehas affirmed before me that he is duly authorized to execute and file the foregoing document in behalf of theCompany, and that the statements in the document a e true to the best of his knowledge and belief.Acknowledged before me day o(._A, .2014.My Commission Expires:

.VICK! L. HULL hNotary PublicCommonwealth of Virginia140542 Notary Pubic(SEAL) My Commission Expires May 31, 2014 Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Page 3 of 3cc

Director of Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission One White Flint NorthMail Stop 13H16M11555 Rockville PikeRockville, MD 20852-2738 U. S. Nuclear Regulatory Commission, Region IIRegional Administrator Marquis One Tower245 Peachtree Center Ave., NESuite 1200Atlanta, Georgia 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 Ms. M. C. BarillasNRC Project Manager SurryU. S. Nuclear Regulatory Commission One White Flint NorthMail Stop 08 G-9A11555 Rockville PikeRockville, MD 20852-2738 Ms. J. A. Kratchman U. S. Nuclear Regulatory Commission One White Flint NorthMail Stop 09 D211555 Rockville PikeRockville, MD 20852-2738 NRC Senior Resident Inspector North Anna Power StationMr. J. E. Reasor, Jr.Old Dominion Electric Cooperative Innsbrook Corporate Center, Suite 3004201 Dominion Blvd.Glen Allen, Virginia 23060 Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment ISix Month Status Report for the Implementation of Order EA-12-051, Order Modifying Licenses with Regard to Requirements forReliable Spent Fuel Pool Instrumentation North Anna Power Station Units 1 and 2Virginia Electric and Power Company (Dominion)

Serial No. 12-166EDocket Nos. 50-338/3.39 Order EA-12-051 Attachment 1Page 1 of 3Six Month Status Report for the Implementation of Order EA-12-051 1 Introduction Dominion developed an Overall Integrated Plan (OIP) (Reference

1) documenting therequirements to install reliable Spent Fuel Pool (SFP) Level Instrumentation in responseto Order EA-12-051 (the Order) (Reference 2). This attachment provides an update ofmilestone accomplishments since submittal of the last status report for North AnnaPower Station Unit 2 (Reference

3) including any changes to the compliance method,schedule, or need for relief/relaxation and the basis, if any.2 Milestone Accomplishments The following milestones have been completed since the development of the NorthAnna Power Station OIP for Order EA-12-051 and are current as of January 31, 2014.0SSubmit OIPCommence Engineering and Design3 Milestone Schedule StatusThe following table provides an update to the milestone schedule supporting the NorthAnna Power Station Overall Integrated Plan. This table provides the activity status ofeach item and the expected completion date noting any change. The target completion dates are subject to change as design and implementation details are developed.

Milestone Target Activity Revised TargetCompletion Date Status Completion DateSubmit OIP February 2013 CompleteCommence Engineering and March 2013 CompleteDesignComplete Engineering and December 2013 Started May 2014DesignComplete Procurement of SFP May 2014 StartedInstruments Commence Installation of SFP March 2014 Not Started June 2014Instruments Level Measurement System September 2014 Not StartedFunctional Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 1Page 2 of 3The revised milestone target completion dates for 'Complete Engineering and Design'and 'Commence Installation of SFP Instruments' do not impact the Orderimplementation date for North Anna Power Station.4 Changes to Compliance MethodThere are no changes to Dominion's compliance method with NEI 12-02; however, thevendor for the SFP Level Instrumentation system has changed to Westinghouse.

TheGuided Wave Radar Technology will continue to be utilized and use of this proventechnology will comply with Order EA-12-051, as described in the NAPS SFP LevelInstrumentation OIP. However, although the same technology is being used, some ofthe design details are being changed from the previously selected level instrumentation system (e.g., mounting brackets).

5 Need for Relief/Relaxation and Basis for the Relief/Relaxation Dominion expects to comply with the order implementation date and no relief/relaxation is required at this time.6 Open Items from Overall Integrated Plan and Interim Staff Evaluation No update is required since there were no open items identified in the North AnnaPower Station Overall Integrated Plan submittal for Order EA-12-051.

Request forAdditional Information (RAI) identified in the Interim Staff Evaluation (Reference

4) areaddressed in Attachment 2 of this letter.7 Potential Interim Staff Evaluation ImpactsOn May 28, 2013, Dominion received RAIs requesting detailed design information regarding the North Anna SFP Level Instrumentation system. At that time, the design ofthe previously selected SFP Level Instrumentation system was not complete and onlysome of the design specifics were provided in a RAI response (Reference 5). Theremaining design details were deferred to a later Six-Month Status Update, some ofwhich were provided in the August 2013 Six-Month Status Update. Subsequently, some of this information was referenced in the Interim Staff Evaluation (ISE) issued onNovember 1, 2013.Dominion has performed a comparison of the new Westinghouse SFP LevelInstrumentation design against the design details that were included in the ISE andwere previously provided in the RAI response and the August 2013 Six-Month StatusUpdate. Dominion concludes that differences in the design details of Westinghouse's Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 1Page 3 of 3new instrumentation that could have potential impact on the NRC ISE are limited to thefollowing:

1) Instrument display accuracy2) Back-up DC power sourceClarification of these design details are addressed in RAI Nos. 16a and 14, inAttachment 2, respectively.

8 References The following references support the update to the North Anna Power Station SFPLevel Instrumentation Overall Integrated Plan described in this attachment:

1. "Virginia Electric and Power Company's Overall Integrated Plan in Response toMarch 12, 2012 Commission Order Modifying Licenses with Regard to ReliableSpent Fuel Pool Instrumentation (Order Number EA-12-051),"

Serial No. 12-166B,dated February 28, 2013.2. NRC Order Number EA-12-051, "Order Modifying Licenses with Regard to ReliableSpent Fuel Pool Instrumentation,"

dated March 12, 2012.3. Virginia Electric and Power Company's Six-Month Status Report in Response toMarch 12, 2012 Commission Order Modifying Licenses with Regard to ReliableSpent Fuel Pool Instrumentation (Order Number EA-12-051),

dated August 23,2013 (Serial No. 12-166D).

4. North Anna Power Station, Units 1 and 2: "NRC Interim Staff Evaluation andRequest for Additional Information Regarding to Overall Integrated Plan forImplementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation,"

dated November 1, 2013.5. "Virginia Electric and Power Company's March 12, 2012 Commission OrderModifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051),

Request for Additional Information (RAI) Response,"

dated July 2, 2013 (Serial No. 12-166C).

Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Order EA-12-051 Interim Staff Evaluation (ISE)Request for Additional Information (RAI) Responses North Anna Power Station Units 1 and 2Virginia Electric and Power Company (Dominion)

Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 1 of 16Six Month Status Report for the Implementation of Order EA-1 2-051Interim Staff Evaluation RAI Responses This attachment provides the responses to the RAls contained in the Interim StaffEvaluation (ISE) and Request for Additional Information regarding the North Anna SFPLevel Instrumentation system received on November 1, 2013.NRC RAI No. 1:Please specify which of the two identified values is the correct elevation for Level 1.Dominion

Response

The correct elevation associated with level 1 (level adequate to support operation of thenormal fuel pool cooling system) is 286.6 ft. (286 ft. 7.2 in.) as provided in calculation MISC-1 1798, "Dominion Fleet Spent Fuel Pool Levels to Provide Adequate NPSH to theCooling Pumps with a Saturated Pool."NRC RAI No. 2:Please provide a clearly labeled sketch or marked-up plant drawing of the plan view ofthe SFP area, depicting the SFP inside dimensions, the planned locations/placement ofthe primary and back-up SFP level sensor, and the proposed routing of the cables thatwill extend from these sensors toward the location of the read-out display device.Dominion

Response

A plan view sketch of the SFP area is provided as Figure 1 below. The sketch depictsthe SFP inside dimensions, the planned locations/placement of the primary and back-uplevel sensors, and the proposed routing of cables that extend the sensors toward thelocation of the electronics.

YSerial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 2 of 16M0.N6,4'0oFigure 1 -North Anna SFP Level Instrumentation Plan View Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 3 of 16NRC RAI No. 3:Provide the following:

a) The design criteria that will be used to estimate the total loading on the mountingdevice(s),

including static weight loads and dynamic loads. Describe the methodology that will be used to estimate the total loading, inclusive of design basis maximumseismic loads and the hydrodynamic loads that could result from pool sloshing or othereffects that could accompany such seismic forces.b) A description of the manner in which the level sensor will be attached to the refueling floor and/or other support structures for each planned point of attachment of the probeassembly.

Indicate in a schematic the portions of the level sensor that will serve aspoints of attachment for mechanical/mounting or electrical connections.

c) A description of the manner by which the mechanical connections will attach the levelinstrument to permanent SFP structures so as to support the level sensor assembly.

Dominion

Response

a) The mounting device (mounting bracket) for the Spent Fuel Pool Instrumentation System (SFPIS) is designated as Quality Classification NSQ (non-safety related,with special quality requirements) in accordance with the Dominion Nuclear QualityAssurance Program.

The mounting bracket design will meet the North Anna PowerStation (NAPS) design and licensing basis requirements for Seismic Category Icomponents, and will include consideration of static weight loads and hydrodynamic loads.The analysis method that will be used to qualify the mounting bracket for the loadingconditions, will include the design basis maximum seismic loads and thehydrodynamic loads that could result from pool sloshing.

The North Anna-specific analysis of the mounting bracket is being performed by Westinghouse (SFPISequipment supplier) and the document providing the methods, design criteria, andresults of the analysis will be available for NRC review upon request.b) The level sensor consists of a stranded stainless steel cable level probe that isthreaded on the top end. The probe attaches (threads) into a coupling that issecured to the mounting bracket launch plate and extends down into the pool. Theattachment to the signal cable is via a coaxial connection on the top side of thelaunch plate coupling.

The mounting bracket is attached to the SFP structure at theconcrete curb utilizing expansion-type concrete anchor bolts.The simplified drawing below shows a representation of the attachment of the probeand the sensor cable to the mounting bracket (launch plate) , and mounting bracketattachment to the SFP structure.

Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 4 of 16Coupling(Bottom )c) The level sensor (probe) is designed to be attached near its upper end to themounting

bracket, as described in the response to RAI #3b above. The mountingbracket will be attached to the SFP concrete curb utilizing expansion-type concreteanchor bolts. The mounting bracket to the SFP structure concrete curb anchorage isdesigned to meet the requirements of the North Anna design and licensing basis forSeismic Category I components including seismic loads, static weight loads andhydrodynamic loads.

Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 5 of 16NRC RAI No. 4:For RAI 3(a) above, please provide the analyses used to verify the design criteria andmethodology for seismic testing of the SFP instrumentation and the electronics units,including, design basis maximum seismic loads and the hydrodynamic loads that couldresult from pool sloshing or other effects that could accompany such seismic forces.Dominion ResponseSection 7 of Westinghouse document WNA-PT-00188-GEN, Rev. 1, "Spent Fuel PoolInstrumentation System (SFPIS) Standard Product Test Strategy,"

provides the overalltest strategy for the SFPIS system, and addresses the design criteria and methodology for seismic testing of the SFP instrumentation and the electronics units. The teststrategy includes seismic response spectra that envelope the design basis maximumseismic loads and includes applicable hydrodynamic loading that could result fromconditions such as seismic-induced sloshing effects.

In accordance with WNA-PT-00188-GEN, the seismic adequacy of the SFPIS equipment is demonstrated inaccordance with the applicable guidance in Sections 7, 8, 9 and 10 of IEEE Standard344-2004, "IEEE Recommended Practice for Seismic Qualification of Class 1EEquipment for Nuclear Power Generating Stations,"

by testing (assemblies with activeelectronic components, sensor housing bracket, electronics panel mounting, coupler,and interconnecting cable) and analysis (sensor probe in pool and pool-side bracket).

The North Anna plant-specific analysis of the sensor probe in pool (sloshing effects) andpool-side bracket is being performed by Westinghouse consistent with the test strategydocument, and the report providing the methods, design criteria, and results of theanalysis and will be available for NRC review upon request.The seismic testing that was performed for the SFPIS is described in Section 4.4 ofWestinghouse document EQ-QR-269, Rev. 0, "Design Verification Testing SummaryReport for the Spent Fuel Pool Instrumentation System,"

and the testing results aredescribed in Section 5.4.3. No equipment failures were noted as a result of theseismic testing.

Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 6 of 16NRC RAI No. 5:For each of the mounting attachments required to attach SFP Level equipment toplant structures, please describe the design inputs, and the methodology that wasused to qualify the structural integrity of the affected structures/equipment.

Dominion

Response

As described in RAI 3a, 3b, and 3c above, the level sensing probe is attached to themounting

bracket, which is anchored to the SFP structure at the concrete curb usingconcrete expansion anchors.

The anchorage to the Seismic Category I SFP structure meets the design requirements described in the response to RAI 3c.Each of the additional SFPIS components required to be mounted / anchored will befixed to plant structures consistent with the North Anna design and licensing basis forSeismic Category I components, and include consideration of design basis maximumseismic loads and static weight loads.NRC RAI No. 6:Please provide analysis of the maximum expected radiological conditions (dose rateand total integrated dose) to which the equipment (including transmitters, control boxes,and display panels) will be exposed.

Also, please provide documentation indicating howit was determined that the electronics for the SFP level instrumentation is capable ofwithstanding a total integrated dose of 1X104 Rads. Please discuss the time period overwhich the analyzed total integrated dose was applied.Dominion

Response

A radiation dose rate analysis was performed to support the radiological assessment requirements defined by NEI 12-02 for the SFP and Auxiliary Building areas, the resultsare provided in Calculation RA-0048, "Radiological Evaluation following a BeyondDesign Basis NAPS SFP Draindown for NEI 12-02." The results of this analysisprovided dose rates and integrated doses for 7-days post-BDB event conservatively assuming SFP water level at one foot above the fuel rack. The analysis also provideddose rates and integrated doses for 40-year normal operation.

The 7-day integrated doses were based on the core inventories (spent fuel sources) at 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> aftershutdown as defined in NEI 12-02. The dose rate analysis resulted in a 7-dayintegrated dose of 3.2X106 Rads at the coupler location in the SFP area. The dose rateanalysis resulted in a 7-day integrated dose of 470 Rads and 40-year integrated dose of880 Rads in the Auxiliary Building where the SFPIS sensor transmitters are located.These values were compared to the design criteria of 107 Rads for the SFP area and103 Rads for the Auxiliary Building area and formed the basis for demonstrating reliability of the permanently installed SFPIS.

Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 7 of 16Radiation test results supplied by Westinghouse in qualification summary test reportEQ-QR-269, "Design Verification Testing Summary Report for the Spent Fuel PoolInstrumentation System" have qualified the coupler and coaxial connecting cable togreater than 107 Rads. This comparison formed the basis for demonstrating reliability ofthe permanently installed equipment located in the SFP area.The SFP level instrumentation electronics utilize Commercial-off-the-Shelf (COTS)components containing Complementary Metal Oxide Semiconductor (CMOS) deviceswhich have been found to be capable of withstanding ionizing dose radiation levels ofup to 103 Rads as described in EPRI 1021067 "Nuclear Power Plant Equipment Qualification Reference Manual,"

Rev. 1, and discussed in RG 1.209, "Guidelines forEnvironmental Qualification of Safety-Related Computer Based Instrumentation andControl Systems in Nuclear Power Plants."

Comparing the calculated integrated dosefor both the short-term post-BDB event and the long-term normal operating conditions tothe industry accepted limit formed the basis to demonstrate reliability of the permanently installed sensor transmitter equipment located within the Auxiliary Building under post-BDB event radiological conditions.

The control box, Uninterruptable Power Supply (UPS), and displays are located in theMain Control Room (MCR) where habitability will be maintained as part of the FLEXstrategies and, therefore, will not be subject to excessive radiological conditions.

NRC RAI No. 7:Please provide information indicating (a) what are the temperature ratings and whetherthe temperature ratings for the system electronics (including transmitters, control boxes,and display panels) are continuous duty ratings; and, (b) what will be the maximumexpected ambient temperature in the rooms in which the system electronics will belocated under BDB conditions in which there are no AC power available to run HeatingVentilation and Air Conditioning (HVA C) systems?Dominion

Response

a) The temperature rating for the electronic equipment located in the Auxiliary Buildingand the MCR (transmitter, control box, UPS, display) is 120 degrees F based on acontinuous duty rating and 140 degrees F under abnormal conditions.

The basis forthe temperature ratings is provided in Section 4.6 of Westinghouse designspecification WNA-DS-02957-GEN, Rev. 2. The temperature rating test results forabnormal conditions are provided in Section 4.5 of Westinghouse report EQ-QR-269, "Design Verification Testing Summary Report for the Spent Fuel PoolInstrumentation System."

Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 8 of 16b) The electronic transmitter equipment will be mounted within the Auxiliary Buildingone elevation below the SFP Operating Deck. This area of the Auxiliary Building isdescribed in NAPS "Environmental Zone Description" and is not expected to exceed95 degrees F during normal operations.

The maximum temperature underpostulated BDB conditions in which there is no ac power available to run heatingventilation and air conditioning (HVAC) systems is not expected to exceed 120degrees F. The room temperatures were analyzed utilizing GOTHIC computational code and the results are included in Addendum O0A to NAPS calculation NA-CALC-MEC-ME-0972, "Evaluation of Room Air Temperatures Following Extended Loss ofAC Power (ELAP)."The displays, control box and UPS are located in the Main Control Room (MCR)where habitability will be maintained as part of the FLEX strategies.

NAPScalculation NA-CALC-MEC-ME-0972 evaluates the MCR temperatures andconcludes the MCR will not be subject to temperature conditions beyond the ratingsstated in RAI 7a.NRC RAI No. 8:Please provide information indicating the maximum expected relative humidity in therooms in which the system electronics will be located under BDB conditions, in whichthere are no AC power available to run HVAC systems, and whether the sensorelectronics are capable of continuously performing its required functions under thisexpected humidity condition.

Dominion

Response

The electronic transmitter equipment will be mounted within the Auxiliary Building oneelevation below the SFP Operating Deck. The maximum humidity for NAPS postulated BDB conditions in which there is no ac power available to run heating ventilation and airconditioning (HVAC) system is expected to be less than 95% relative humidity whichwas analyzed utilizing GOTHIC computational code and the results are included inAddendum O0A to NAPS calculation NA-CALC-MEC-ME-0972, "Evaluation of Room AirTemperatures Following Extended Loss of AC Power (ELAP)".

Equipment testingunder normal and abnormal conditions with humidity levels up to 95% were performed by Westinghouse and the results documented in Section 4.5 of EQ-QR-269, "DesignVerification Testing Summary Report for the Spent Fuel Pool Instrumentation System."The results from testing performed by Westinghouse compared to the maximum post-BDB event humidity level of 95% was found to be acceptable.

This comparison formedthe basis to demonstrate reliability of the permanently installed electronic equipment located within the Auxiliary Building under the post-BDB event conditions for relativehumidity.

Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 9 of 16The displays, control box and UPS are located in the Main Control Room (MCR) wherehabitability will be maintained as part of the FLEX strategies.

It is reasonable toassume that the MCR relative humidity would not be any greater than the humidityexperienced in the Auxiliary Building areas. Therefore, the MCR will not be subject toconditions greater than 95% relative humidity.

NRC RAI No. 9:Please provide information describing the evaluation of the comparative sensor design,the shock test method, test results, and forces applied to the sensor applicable to itssuccessful tests demonstrating that the referenced previous testing provides anappropriate means to demonstrate reliability of the sensor under the effects of severeshock.Dominion

Response

The Westinghouse SFPIS sensor consists of a stainless steel braided cable probeattached to a permanently installed mounting bracket anchored to the SFP deck. In theinstalled locations, the SFPIS sensors (probes) will not be subject to shock and vibration loading conditions other than those induced by seismic motions.

The SFPIS is subjectto testing for anticipated maximum seismic conditions as described in the response toRAI No. 4. Section 8.2.4 (Shock and Vibration Qualification)

[DS-02957-1621]

ofWestinghouse document WNA-DS-02957-GEN, Rev. 2, "Spent Fuel PoolInstrumentation System Design Specification,"

provides justification that no additional vibration and shock testing is required.

NRC RAI No. 10:Please provide information describing the evaluation of the comparative sensor design,the vibration test method, test results, and the forces and their frequency ranges anddirections applied to the sensor applicable to its successful tests, demonstrating that thereferenced previous testing provides an appropriate means to demonstrate reliability ofthe sensor under the effects of high vibration.

Dominion

Response

See Response to RAI No. 9 above.NRC RAI No. 11:Please provide information describing the evaluation of the comparative systemelectronics (including transmitters, control boxes, and display panels) ratings againstpostulated plant conditions.

Also provide results of the manufacturer's shock andvibration test methods, test results, and the forces and their frequency ranges and Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 10 of 16directions applied to the system electronics and display panel associated with itssuccessful tests.Dominion

Response

The SFPIS system electronics associated with both SFP level instrument channels willbe permanently installed and anchored to structural walls of seismic category 1structures and will not be subject to shock or vibration inputs other than those inducedby seismic motions.

The SFPIS is subject to testing for anticipated maximum seismicconditions as described in the response to RAI No. 4. Section 8.2.4 (Shock andVibration Qualification),

[DS-02957-1621]

of Westinghouse document WNA-DS-02957-GEN, Rev. 2, identifies that shock and vibration qualification of the system electronics (including transmitters, control boxes, and display panels) is accomplished by seismictesting and provides justification that no additional vibration and shock testing isrequired.

NRC RAI No. 12:Please provide the following:

a) A description of the testing and/or analyses that will be conducted to provideassurance that the equipment will perform reliably under the worst-case credible designbasis loading at the location where the equipment will be mounted.

Include a discussion of this seismic reliability demonstration as it applies to (a) the level sensor mounted inthe SFP area, and (b) any control boxes, electronics, or read-out and retransmitting devices that will be employed to convey the level information from the level sensor tothe plant operators or emergency responders.

b) A description of the specific method or combination of methods that will be used toconfirm the reliability of the permanently installed equipment during and following seismic conditions to maintain its required accuracy.

Dominion

Response

a) Testing and analysis is conducted by Westinghouse to provide assurance that theequipment will perform reliably under the worst-case credible design basis loading atthe location where the equipment will be mounted.

North Anna Procurement Specification IC-1210, Rev. 1, provides the design requirements applicable to theinstalled location for the equipment.

Section 7 of Westinghouse document WNA-PT-00188-GEN, Rev. 1, "Spent Fuel Pool Instrumentation System (SFPIS) StandardProduct Test Strategy,"

provides the overall test strategy for the SFPIS system, andaddresses the design criteria and methodology for seismic testing of the SFPinstrumentation and the electronics units. The test strategy includes seismicresponse spectra that envelope the design basis maximum seismic loads andincludes applicable hydrodynamic loading that could result from conditions such as Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 11 of 16seismic-induced sloshing effects.

In accordance with WNA-PT-00188-GEN, theseismic adequacy of the SFPIS equipment is demonstrated in accordance with theapplicable guidance in Sections 7, 8, 9 and 10 of IEEE Standard 344-2004, "IEEERecommended Practice for Seismic Qualification of Class 1 E Equipment for NuclearPower Generating Stations,"

by testing.The seismic testing performed is described in Section 4.4 of Westinghouse document EQ-QR-269, Rev. 0, "Design Verification Testing Summary Report for theSpent Fuel Pool Instrumentation System."b) The method (testing) and associated performance and acceptance criteria used toconfirm the reliability of the SFPIS during and following seismic conditions aredescribed in Section 2.2 and subsection 3.2.1 of Westinghouse document EQ-QR-269, respectively.

The testing addresses the reliability of the permanently installed equipment to maintain required accuracy following seismic conditions.

Confirmation of SFPIS function and accuracy following seismic testing is adequate to assurereliability since no operator readings or consequential action will be taken until aftera seismic event.NRC RAI No. 13:For RAI #12 above, please provide the results for the selected

methods, tests andanalyses used to demonstrate the qualification and reliability of the installed equipment in accordance with the Order requirements.

Dominion

Response

Results of seismic testing is documented in subsection 5.4.3 of Westinghouse DesignVerification Testing Summary Report EQ-QR-269.

The equipment met the requiredperformance and acceptance criteria described in subsection 3.2.1 of EQ-QR-269.

The SFPIS maintained accuracy and structural integrity, and acceptable functionality was confirmed at the completion of seismic testing.NRC RAI No. 14:Please provide the following:

a) A description of the electrical AC power sources and capabilities for the primary andbackup channels.

b) Please provide the NRC staff with the final configuration of the power supply sourcefor each channel so that the staff may conclude that the two channels are independent from a power supply assignment perspective.

Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 12 of 16Dominion

Response

a) Each instrument channel is normally powered by a 120 VAC distribution panels tosupport continuous monitoring of the SFP level. The 120 VAC distribution panels forthe primary and backup channels are powered by different 480 VAC buses.Therefore, the loss of either of the 480 VAC buses will not result in the failure of bothinstrument channels.

On loss of normal 120 VAC power, each channel is equippedwith a separate UPS that will automatically transfer to a dedicated 72-hour back-upbattery.

If normal power is restored, then the instrument channels will automatically transfer back to the normal 120 VAC power source. The backup batteries aremaintained in a charged state by the associated UPS.The instrument channels can also be powered through a manually selected alternate AC power source, if available.

The Westinghouse SFP Level Instrumentation system design does not include an optional external DC power input.b) See response to RAI #14a above.NRC RAI No. 15:Please provide the results of the calculation depicting the battery backup duty cyclerequirements demonstrating that its capacity is sufficient to maintain the level indication function until offsite resource availability is reasonably assured.Dominion

Response

Westinghouse document WNA-CN-00300-GEN, Rev. 0, "Spent Fuel PoolInstrumentation System Power Consumption Calculation,"

documents the SFPIS powerconsumption analysis.

Table 5-7 (Level Wired Cabinet, 3-Day Battery Charge PowerConsumption) reflects the configuration to be used at North Anna.The calculation concludes that, with an initial full charge, the battery will maintain thelevel indication function without ac power for 101.21 hours2.430556e-4 days <br />0.00583 hours <br />3.472222e-5 weeks <br />7.9905e-6 months <br /> (4.22 days). With anadditional remote display connected to the SFPIS, the battery can maintain the levelindication function for 3 days.The results of the calculation show the battery will provide adequate time for off-siteresources to be deployed by the mitigating strategies resulting from Order EA-12-049.

Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 13 of 16NRC RAI No. 16:Provide the following:

a) A description of the methodology that will be used for determining the maximumallowed deviation from the instrument channel design accuracy that will be employedunder normal operating conditions as an acceptance criterion for a calibration procedure to flag to operators and to technicians that the channel requires adjustment to within thenormal condition design accuracy.

b) Please provide analysis verifying that the proposed instrument performance isconsistent with these estimated accuracy normal and BDB values. Please demonstrate that the channels will retain these accuracy performance values following a loss ofpower and subsequent restoration of power.Dominion

Response

a) Westinghouse document WNA-DS-02957-GEN, Rev. 2, "Spent Fuel PoolInstrumentation System Design Specification,"

provides the required displayaccuracy of the level indication as within +/- 3 inches of the entire range, which is fromnormal water level to the top of the fuel racks under all environmental conditions.

(Note: This display accuracy is for the Westinghouse SFPIS and is a change fromthe value previously reported.)

Westinghouse document WNA-CN-00301-GEN, Rev.0, "Spent Fuel Pool Instrumentation System Channel Accuracy Analysis,"

providesthe SFPIS channel accuracy analysis.

Westinghouse document WNA-TP-04709-GEN, Rev. 3, "Calibration Procedure,"

provides the instructions for calibration of the SFPIS. The calibration check isintended to be performed within 60 days of a planned refueling outage, but not morefrequently than once per 12 months. The calibration procedure specifies the alloweddeviation from the instrument channel required accuracy that initiates a requiredadjustment to within the normal condition design accuracy.

b) Westinghouse document WNA-CN-00301-GEN, Rev. 0, "Spent Fuel PoolInstrumentation System Channel Accuracy Analysis,"

provides the SFPIS channelaccuracy analysis verifying that the instrument performance is consistent with theaccuracy requirements during normal and abnormal conditions.

As described in the response to RAI No. 16 a), Westinghouse document WNA-TP-04709-GEN, Rev. 3, "Calibration Procedure,"

provides the instructions for routinecalibration of the SFPIS to ensure that instrument performance is consistent withaccuracy requirements during operation.

The results of qualification testing are documented in Westinghouse DesignVerification Testing Summary Report EQ-QR-269.

These results demonstrate that Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 14 of 16the channels retained the design accuracy at the completion of each test including loss of power and subsequent restoration of power.NRC RAI No. 17:Please provide a list of the procedures addressing operation (both normal andabnormal response),

calibration, test, maintenance, and inspection procedures thatwill be developed for use of the SFP instrumentation.

The licensee is requested toinclude a brief description of the specific technical objectives to be achieved withineach procedure.

Dominion

Response

Appropriate quality assurance measures that are consistent with Appendix A-1 of NEI12-02 will be established for the SFP level instrumentation as required by order EA-12-051. Site specific procedures will be developed for system inspection, calibration andtest, maintenance, repair, operation, and normal and abnormal responses inaccordance with NAPS procedural controls and will be based on recommended operation and maintenance procedures provided by Westinghouse.

Technical objectives will be achieved through NAPS specific procedures based on the following general types:Type of Procedure Obeective to be Achieved1) System Inspection

2) Calibration and Test3) Maintenance

4) RepairTo verify the system components are in place,complete, and in the correct configuration, and thatthe sensor probe is free from significant boric aciddeposition To verify that the system is within specified

accuracy, is functioning as designed, and is properlyindicating SFP levelTo establish and define scheduled and preventative maintenance requirements and activities necessary to minimize the possibility of interruption To specify troubleshooting steps and component repair and replacement activities in the even of asystem malfunction To provide sufficient instructions for operation and5) Operation Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 15 of 16Type of Procedure Objective to be Achieveduse of the system by plant staff personnel

6) FLEX Support To define the actions to be taken upon observation Guideline (FSG) of system level indications, including actions to betaken at the levels defined in NEI 12-02NRC RAI No. 18:Please provide the following:

a) Further information describing the maintenance and testing program the licenseewill establish and implement to ensure that regular testing and calibration isperformed and verified by inspection and audit to demonstrate conformance withdesign and system readiness requirements.

Please include a description of theplans for ensuring that necessary channel checks, functional tests, periodiccalibration, and maintenance will be conducted for the level measurement systemand its supporting equipment.

b) Information describing compensatory actions when both channels are out-of-order, and the implementation procedures.

c) Additional information describing expedited and compensatory actions in themaintenance procedure to address when one of the instrument channels cannot berestored to functional status within 90 daysDominion

Response

a) Channel Check is not a specified requirement in NEI 12-02. Channel Check isspecified in IEEE 338-1987 for Safety Systems.

SFP level instrument channels arenot safety related and are not subject to testing requirements of safety relatedinstrumentation.

If the plant staff determined a need to confirm that the twochannels are performing as expected, the two channels may be read in the MainControl Room. While the SFP is operating within design basis and at normal level,the indicators may be compared to fixed marks within the SFP by visual observation to confirm indicated level. The periodic calibration verification will be performed within 60 days of a refueling outage considering normal testing scheduling allowances (e.g., 25%). Calibration verification will not be required to be performed more than once per 12 months. These calibration requirements are consistent withthe guidance provided in NEI 12-02 section 4.3. Periodic calibration verification procedures will be in place based on information provided by Westinghouse in WNA-TP-04709-GEN, "Spent Fuel Pool Instrumentation System Calibration Procedure."

Preventive maintenance procedures to include tests, inspection and periodic Serial No. 12-166EDocket Nos. 50-338/339 Order EA-12-051 Attachment 2Page 16 of 16replacement of the backup batteries will be developed based on recommendation from Westinghouse.

b) Provisions associated with out of service (OOS) or non-functional equipment including allowed outage times and compensatory actions will be consistent with theguidance provided in Section 4.3 of NEI 12-02. If one OOS channel cannot berestored to service within 90 days, appropriate compensatory

actions, including theuse of alternate suitable equipment, will be taken. If both channels become OOS,actions would be initiated within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore one of the channels to operablestatus and to implements appropriate compensatory

actions, including the use ofalternate suitable equipment and/or supplemental personnel, within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.Additionally, if both channels are OOS, a Condition Report will be initiated andaddressed through the Dominion's Corrective Action Program.North Anna will maintain sufficient spare parts for the SFPIS, taking into account thelead time and availability of spare parts, in order to expedite maintenance activities, when necessary, to provide assurance that a channel can be restored to servicewithin 90 days.c) See response to RAI 18b.