ML16155A084

APS Response to Request for Additional Information Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Lnstrumentation

ML16155A084
Person / Time
Site:	Palo Verde
Issue date:	04/29/2016
From:	Lacal M Arizona Public Service Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
102-07248-MLL/TNW/PJH, EA-12-051
Download: ML16155A084 (32)

Text

EA-12,-051 Oaps MARI~ L, LACAL Senior Vice President Nuclear Regulatory and Over-Sight Palo Verde Nuclear Generating Station P.O. Box 52034 Phoenix, AZ 85072 Mali Station 7605 102-07248-MLL/TNW/PJH Tel 623.39~:6491 April 29, 2016 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk 11555 Rockville Pi~e Rockville, MD 20852

References:

1. NRC Order Number EA-12-051, Order Modit'ying Licenses with Regard to Reliable Spent.Pue/ Pool L'eve/ Instrumentation, dated March 12, 20;1.2 .

2. NRC Letter, Palo Verde Nuclear Generating Station, Units 1, 2, and 3 - Interim Staff !;valuation and Request tor Additional Information (RAI) Regarding Overall Integrated Plan for Implementation of Order EA-12-051, "Reliable Spent Fuel Pool Instrumentation (SFPI)," dated October 29, 2013

3. NRC Email, NRC Staff Request for FLEX $FPI Information, dated May 13, 2014

4. NRC Email, NRC Request to Docket Palo Verde FLEX SFPI RAis, dated March 19, 2016

Subject:

Palo Verde Nuclear G~nerating Station (PVNGS)

Units 1, 2, and 3 Docket Nos. STN 50-528, 50-529, and 50-530 APS Response to Request for Additional Information Regarding Overall Integrated Plan for Implementation of Order EA 051, Reliable Spent Fuel Pool lnstrumentai:ion On March 12, 2012, the Nuclear R~gulatory Commission (NRC) issued an order (Reference 1) to Arizona Public Service Company (APS). Reference 1 was immediately effective and directed that PVNGS must have a reliable means of remotely monitoring Wide-range Spent Fuel Pool (SFP) levels to support effective

• prioritization of event mitigation and recovery actions in the event of a beyond-design-b~sis ~xternal event. Specific requirements are outlined in Attachment 2 of Reference 1.

The NRC issued PVNGS Interim Staff Evaluation {IS!:) and RAI regarding the overaU integrated plan. for implementation of Order EA-12-051 in Reference 2. These RA!

responses were provided in the electronic reading room. The enclosure to this letter contains the APS responses to the NRC RAis contained in References 3 and 4. These RAI responses have been updated to reflect current practices and/or configuration information.

A member of the STARS (Strategic Teaming and Resource Sharing)

Callaway

• Diablo Canyon

• Palo Verde

• Wolf Creek

102-07248-MLL/TNW/PJH ATTN: Do~ument Control Desk U.S. Nuclear Regulatory Commission

~PS Response to RAis Reg~rding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation Page 2 No commitments are being made to the NRC by this letter.

Should you have any questions concerning the content of this letter, please contact Mike Dilorenzo, Section Leader, Nuclear Regulatory Affairs, at (623) 393-3495.

I declare under penalty of perjury that the foregoing is true anq c:orrect.

Executed on APtZ-1 L 2 0/ '2.0/ t/;

(Date)

Sincer~ly, MLL/TNW/PJH/af

Enclosure:

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation cc: M. L. Dapas NRC Region IV Regional Administrator S. P. Lingam NRC NRR Project Manager for PVNGS M. M. Watford NRC NRR Project Manager C. A. Peabody NRC Senior Resident Inspector far PVNGS J.P. Boska NRC NRR/JLD/PPSD/JOMB Project Manager A member of the STAR8 (Strategic Teaming and Resource Sharing) Alliance Callaway

• Diablo Canyon

• Palo Verde

• Wolf creek

ENCLOSURE Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order ~A-12-051, R.~liable Spent fuel Pool Instrumentation INTRODUCTION On March 12, 2012, the U.S. Nuclear R~gulatory Commission (NRC) issued Order EA-12-051, Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation [Agencywide Documents Access and Management System (ADAMS)

Accession No. ML12054A679], to all power reactor licensees and holders of construction permits in active status. This order required licensees to have a reliable indication of the water level in associated spent fuel storage pools capabl~ of supporting identification of the following pool water level conditions by trained personnel: ( 1) level that is adequate to support operation of the normal fuel pool cooling system, (2) level that is adequate to provide substantial radiation shielding for a person standing on the Spent Fuel Pool operating deck, and (3) level where fuel remains covered and actions to implement make-up water addition should no longer be deferred.

By letter dated February 28, 2013 (ADAMS Accession No. ML13070A077), Arizona Public Service Company (APS) provided the Overall Integrated Plan (OIP) for the Palo Verde Nuclear Generating Station {PVNGS) describing how compliance with of Order EA-12-051 would be achieved; by fall 2014 for Unit 1, fall 2015 for Unit 2, and spring 2015 for Unit 3 .. By letter dated June 10, 2013 (ADAMS Accession No. ML13157A065), the NRC staff provided a request for additional information (RAJ) to APS. Supplemental information was provided to the NRC by APS letter nu.mbers 102-06728 dated July 11, 2013 (ADAMS Accession No. ML13199A033), and 102-06759 dated August 28, 2013 {ADAMS Accession No. ML13246A008). By letter dated October 29, 2013 (ADAMS Accession No. ML13296A006), the NRC staff provided a request for additional information (RAI) to AP5j. NRC Email, dated March 23, 2016, requested the RAI responses be docketed.

This enclosure contains the APS response to the RAis regarding Reliable Spent Fuel Pool Instrumentation updated to reflect current practices *and/or configuration Information. The NRC staff introductory information in the October 29, 2013 letter, related to the background for the RAis, is not included in this enclosure. The request for information is restated, followed by the AP~ response.

1

Respon*se to NRC ~Is Regarding {)vercill Integrated Plan for Implementation of Order EA-12-~05i, Re!iiJl;J/e spent Fuel Pool Instrurnentation Order EA-12-051. Rel_iable Spent Fuel Pool Instrumentation RAI #i DescriDtion of Other SFP Structures Please j>tovjde tf~e followiil~:

a) A description of h.ow the other structures in ~he vicinity of the SFPs (cask loading pit, transfe*r canals and *gates) shown iil Figure *2, "Spent Fuel P.ool Geometry and Dimen.sions;' are conn*ected to the SFPs.

• b) If additional structures, other than the SFP~ i.n each unit, are used for fuel storage, d~scribe in detail their usage, operation, and provide ju~tifications for not installing s.eparate level instrl.iineritation in other*

structures used for fuel storage.

APS Response a) The Spent Fuel Pool (SFP) is connected to two refueling structures; the Transfer Canal and the Cask Loading Pit, reference Figure 1. A Seismic Category I gate, with dual seals separates the inventory betwe~n the SFP and the Cask Loading Pit. A Seismic Category I gate and seal separ~tes the inventory between the SFP artd the Transfer Canal. This seal is currently being modified to a dual seal design independent of Order EA-12-051. In addition, a Seismic Category I gate, with dual seals, separates the inventory between the Cask Loading Pit and the Cask Decontamination Pit, which connect:S to the Fuel Building at grade elevation. This gate is only removed during dry cask campaign? when the gate between the SFP and Cask Loading Pit is installei;I. The lowest elevation of the gate between the Cask Loading Pit and the c;ask Decontamination Pit is 124 feet, O inches which is above the tpp of the SFP storage rack (114 feet, 2 inches). The dual gate seals are pressurized by a redundant, air ahd nitrogen gas supply and have an additional Seismic Category I back,.up nitrogen source~ The SFP is configured to comply with the requirements of Regulatory Gµide l.i.3, Spent Fuel Storage Facility Design Basis, Revision 0.

b) The independent spent fuel storage installation (ISFS~) is designed to store PVNGS irradiated spent nuclear fuel. The ISFSI consists of twelve large rectangular concrete pads. The concrete storage pads are apprqximately 285 feet Icing by 35 feet wide and are situated In a 3-pad by 4-pad array. Each storage pad is designed to accommodate 28 spent fuel storage.casks arranged in two parallel rows of i4 casks. NAC international Inc. (NAC) was selected as the cask

?Ystem supplier for Palo Verde. The NAC spent fuel cask system is_ a canister-based design for storage of sp~nt nuclear fuel. After the ta.sl!:p' TRUE NORTI!

SPENI' FUEL POOL CASK LOADING OECON PIT GATE GATE CASK DECONrA.WNAllO PIT FIJEL (NEW)

!NSPECllON PIT 1~

Plan Vjew Figure 1 3

Response to NRC RAis Regard ing Overall Integrated Plan for Implementation of Order EA 051 , Reliable Spent Fuel Pool Instrumentation Order EA-12-051. Reliable Spent Fuel Pool Instrumentation RAI #2 Summary of Proposed Wireless Technology Please provide your plant-specific performance evaluation result and a brief summary of the proposed wireless technology that will be used in the primary and backup measurement systems to address the criteria summarized in Section 3.1 of NEI 12-02.

APS Response PVNGS opted to use hardwired SFP level measurement systems instead of wireless, for both the primary and alternate systems installed in each SFP. The hardwired

" system for level instrumentation meets each of the requirements of Section 3.1 of NEI 12-02, Industry Guidance for Compliance with NRC Order EA-12-051 , "To Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation."

4

Response t o NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA- 12-051, Reliable Spent Fuel Pool Instrumentation Order EA- 12-051. Reliable Spent Fuel Pool Instrumentation RAI #3 Primary and Back-Up SFP Level Sensor Please provide the following:

a) The final locations/placement of the primary and back- up SFP level sensor.

b) Additional information describing how the proposed arrangement of the sensor probe assembly and routing of the cabling between the sensor probe assembly and the electronics in the Auxiliary Building meets the Order requirement to arrange the SFP level instrument channels in a manner that provides reasonable protection of the level indication function against missiles that may result from damage to the structure over the SFP.

APS Response a) The primary instrument channel sensor Is mounted in accordance with JN350-A00038 (Reference 17 of th is enclosure) in the northeast corner of the SFP on th e east wall. The back-up (alternat e) instru ment channel sensor is located in the southeast corner of the Spent Fuel Pool (SFP) on the south wall, as shown in Figure 2.

b) Physica l separation of the primary and alternate Instrument channel signal cables and power cables is maintained using train separation requirements identified in PVNGS Specification 13-EN-0611, Installation Specification for Reg. Guide 1.75 Cable and Raceway Separation. The IEEE Standards for the Level Sensor Coaxial Signal Cable are IEEE 323-2003, IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations, and IEEE 383-2003, IEEE Standard for Qualifying Class 1 E Electric Cables and Field Splices for Nuclear Power Generating Stations.

The Resistance Temperatu re Detector {RTD} Cables meet the requirements of IEEE-572- 1985, IEEE Standard for Qualification ofClass 1£ Connection Assemblies for Nuclear Power Generating Stations, IEEE- 383- 1974, IEEE Standard for Type Test of Class 1 E Electric Cables, Field Splices, and Connections for Nuclear Power Generating Stations, and IEEE - 1202- 1991, IEEE Standard for Flame Testing of Cables for Use in Cable Tra y in Industrial and Commercial Occupancies, as shown on document JN350-A00010 (Reference 1 of th is enclosure) .

The sensors are located close to th e side walls of the SFP and below the floor elevation to utilize the pool walls as inherent protection . From the primary sensor, the primary signal cable, contained in rigid metal conduit , is run east along the floor to the east wall of the Fuel Building . The primary signal cable is t hen routed along the east wall until it penetrates the wall into the Aux iliary Bu ilding. From the alternate sensor, the alternate signa l cable, contained in rigid metal conduit, is run east along the fl oor to the east wall of t he Fuel Building. The alternate signal cable is then routed along the east wall until it penetrat es the 5

Response to NRC RAIS Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation wall into the Auxil iary Building. The raceway containing the signal cables share only a small distance along the common east wall of the Fuel Building where they penetrate the wall and enter the Auxiliary Building .

Once the cables enter the Auxil iary Building they are routed to separate locations prior to connecting to the electronics. The SFP walls and comers provide inherent missile protection for the level sensor cable. See Figure 2 for a depiction of the conduit routing.

The Fuel and Auxili ary Buildings are classified as Seismic Category I structures designed to remain intact and functional following a Safe Shutdown Earthquake (SSE) or Operating Basis Earthquake (OBE) event. The inherent design function of the structures precludes any part of the building structure from falling or becoming a missile during/after a seismic event. Seismic Category I components attached to the building structures are designed to the same requirements as the structures and will remain intact and functional following an

• SSE or OBE event. Non-Seismic Category I components are also attached to the bui lding structures. These components are classified as Seismic Category IX and are designed to remain intact following an SSE event. Seismic Category IX components are not required to rema in functional and can deform but are designed to preclude falling or becoming a missile during/after a seismic event.

Additionally, Seismic Category I structures are designed for, and protected against, the effects of internal and external missiles. The missiles considered were both tornado-generated (external) and internally-generated (i.e., turbine missiles). For each potential missile, its origin, size, impact velocity or energy, and direction were considered . Seismic Category I structures were analyzed for these values per the analysis and design guidelines of Bechtel Topical Report BC-TOP-9A, Design of Structures for Missile Impact, UFSAR Section 3.5, Missile Protection, and UFSAR Appendix 3C, Design of Structures for Tornado Missile Impact. Missile-resistant barriers and structures were designed to withstand and absorb missUe impact loads in order to prevent damage to protected structures, systems, and components.

Tornado missile protection for Seism ic Category I structures, other than the Containment Building, is provided by the following exterior wall and roof thicknesses:

• Walls : Minimum 21 inches (f' c = 4000 lb./in 2 )

• Roofs: Minimum 16 inches (f' c = 5000 lb./in 2 )

6

Response to NRC RAis Regard ing Overall Integrated Plan for Implementation of Order EA-12-05 1, Reliable Spent Fuel Pool Instrumentation Back-up (alternate) instrument channel sensor location Primary instrument channel sensor location

- - - Primary

- - - Alternate Routing of Sensor Cables from Sensor Location to Display Locations Figure 2 7

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order l;:A-12-051, Reliable Spent Fuel Pool Ins.trumenta~ipn Order EA-12-051, Reliable Spent Fuel Pool Instrumentation RAI #4 Seismic Testing of the Sensor Probe Assembly Please provide the analyses verifyfog that the seismic testing of the sensor probe assembly and the ele.ctronics units, and the licensee's analysis of the combined maximum seismic and hydrodyn~mic forces on the sensor probe assembly exposed to the potentiaf sloshing effects, show that the SFP instrument design configuration will be maintained during and following the maximum seismic ground motion considered in the design of the SFP structure.

APS Response Level Sensor Bracket: The mounting bracket for the sensing pro~e was designed according to the plant design basis for Safe Shutdown Earthquake (SSE) seismic hazard curve at the pool deck elevation, as documented in JN350-A00083 (Reference 2 of this enclosure). Loads that were considered in the evaluation of the bracket and its mounting are: *

(1) Static loads including the dead weight of the mounting bracket in addition to the weight of the level sensing instruments, stilling well and cabling; (2) Dynamic loads including the seismic load due to excitation of the instruments dead weight in addition to the hydrodynamic effects resulting from the excitation of the SFP water.

A response spectra analysis was performed for the seismic evaluation of the mounting bracket using GTSTRUDL (Reference 3 of this enclosure). Hydrodynamic effects on the mounting bracket were evaluated using Technical Report Nuclear Reactors and Earthquakes, TID-7024, dated August 196;3 and added to the GTSTRUDL model. Plant acceptance criteria and applicable codes were used for the design of the bracket and Its anchorage.

Results were shown to be adequate for the loads and load combinations used in the analysis. Welded and bolted connections were evaluated and were shown to be adequate. The base plate of the mounting bracket and the anchorage to the concrete were evaluated using Plate Wizard in GTSTRUDL and designed to meet the plant criteria for base plates and anchors.

Spent Fuel Pool Instrumentation System CSFPISl Equipment {sensor and electronics): The seismic testing for the Sensor and Electronics is documented in JN350-A00076 (Reference 4 of this enclosure). The seismic testing was satisfied for SSE in accordance with IEEE 344-2004, IEEE Recommended Practice for Seismic Qualification of Class 1E Equipment for Nuclear Power Generating Stations, Required Response Spectra (RRS) to IEEE 323-2003 with 10% margin included. SSE is shown in Figure 3. The Operating Basis Earthquake (OBE) RRS at 5% critical damping was at least 70% of the respective SSE seismic level of Figure 3.

The sensor and electronics met each of the required performance and acceptance criteria, maintained structural integrity during the acceptable SSE test runs, and acceptaple QBE test runs to the RRS. Acceptable functionality of the electronics and 8

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation sensor was confirmed upon completion of seismic testing. In accordance with the requirements of JN350-A00076 (Reference 4 of this enclosure), testing included five successful OBE tests and two successful SSE tests. The post-test .inspection, performed upon completion of the seismic tests, revealed no major structural issues or damage.

SFPIS DBE and SSE Required Response Spectrum

• 5% Critical Damping 1 10 100 Frequency (HZ)

SFPIS OBE and SSE RRS for all Principal Directions at 50/o Critical Damping (100/o Margin Included)

Figure 3 9

Response to NRC RAis Regarding Overall Integrated l?l'an for Implementation of Order EA-12-051, Reliable Spent Fuel Pool jnstrumentation Order EA...12-051. Reliable Spent Fuel Pool Instrumentation RAI #5 Mounting Attachments for SFP Level Equipment For each of the mounting attachments required to attach SFP Level equipment to plant structures, please describe the design iraputs, and the methodology that was used to qualify the st.ructural integrity of the affect~d structures/ equipment.

APS Response The design input and qualification methodology is consistent with the current seismic design for existing plant structures/equipment.

• With the exception of the level sensor probe mounting bracket which was qualified by analysis, all the system equipment is seismically qualified by testing. The outputs of the seismic test of equipment were used as the design input for the qualification of the mounting of that specific equipment.

The sensing prope mounting bracket was designed accordin*g to the plant design basis for Safe Shutdown Earthquake (SSE) or Operating Basis Earthquake (OBE) at the appropriate plant elevation. In order to ensure adequate design margin for the SSE and OBE events, the seismic inputs were increased by 10%. The following loads that were considered in the evaluation of the bracket and its mounting:

(1) Static loads including the dead weight of the mounting bracket in addition to the weight of the level sensing instruments, stilling well and cabling; (2) Dynamic loads including the seismic load due to excitation o(the dead weight of the system in addition to the hydrodynamic effects resulting from the excitation of the SFP water.

A response Spectra analysis was performed for the seismic evaluation of the mounting bracket using GTSTRUDL software (Reference 3 9f this enclosure) and using floor response spectrum at the operating deck elevation as identified in the PVNGS UFSAR Revision 17 and the Palo Verde Design Basis Manual CS, Revision 4, Seismic Topical. Hydrodynamic effects on the mounting bracket were evaluated using Technical Report Nuclear Reactor~ and Earthquakes, TID-7024, dated August 1963. Plant acceptance criteria and applicable codes were used for the design of the bracket and its anchorage. Evaluations of support members and connections showed a design margin of 10% or more (JN,350-A0.0083, Reference 2 of this enclosure).

The seismic testing for the sensor electronics bracket is documented in JN350-A00076 (Reference 4 of this enclosure). The seismic testing was satisfied by performing seismic testing to the SSE in accordance with IEEE 344-2004. The Required Response Spectra (RRS) in accordance with IEEE 323-2003 Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations including a 10% margin.

10

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation

• order EA-12-051. Reliabie Spent Fuel Pool.Instrumentation RAI #6 Radiological Conditions at Equipment Location Please provide analysis of the maximum expected radiological conditions (dose rate and total integrated d~se) to which the equipment located within the control building or AB [Auxiliary Building] will be exposed. Also, please provide documentation indicating the radiological dosage amount that the electrQnics for this equipment is capable of withstanding. Please di.scuss the time period over which the analyzed total integrated dose was applied.

APS Response During a beyond-design-basis external event (BDBEE) it is expected that conditions in the Auxiliary and Control Buildings are consistent with the normal operating conditions established in the PVNGS Equipment Qualification (EQ) Program Manual.

For the Auxiliary Building Total Integrated Dose (TIO) for a 40 year period is 1.00 E0.6 Rads gamma at the location of the subject instrumentation. TIO for the 140 foot of the Control Building is not identified in the EQ Program Manual as it is considered a mild environment. Mild environment conditions are those occurring during normal plant operation (all modes), including any abnormal operating occurrence. For the Auxiliary Building and Control Building, all areas with instrumentation dose rates are typically <0*.2 mRem per hour.

A summary of the radiological conditions to which the equipment is qualified is provided below.

Radiological conditions for the Spent Fuel Pool Instrumentation System (SFPIS) components in the SFP area:

The coaxial cable, the c<;>upler, the p<;>ol-side bracket, and the probe In the SFP area will operate reliably in the seniice environmental conditions specified in the table below.

Parameter Normal*, Beyond Design Basis*

Radiation TIO 1.00 E03 Rads (above pool) aamma 1.00 E07 Rads gamma R9diation TIO 1.00 E09 Rads

(.12" above top of fuel gamma rack) (probe & weiaht onM LOO E07 Rads gamma

• Per Table 4. L2-1 of JN350-A00079 (Reference 5 of this enclosure) and Table 4.8-1 of JN350-A00078 (Referem;e 9 of this enclosure)

The SFP area radiological conditions are detailed In JN350-A00079 (Referen!=e 5 of this enclosure).

• 11

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation Radiological conditions outside of the SFP area:

The level sensor electronics (i.e., transmitter), sensor electronics bracket, indicators, and the electronics enclosures outside of the SFP area are required to operate reliably in the service environmental conditions specified in the table below.

Beyond Design Parameter Normal**

Basis**

Radiation TID ~ 1E03 Rads gamma ~ 1E03 Rads qamma

• • Per Table 4.1.3-1 of JN350-A00079 (Reference 5 of this enclosure) and Table 4.8-2 of JN350-A00078 (Reference 9 of this enclosure)

\

I 12

R,esponse to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable spent Fuel Pool Instrumentation Order EA-12-051. Reliable Sqent Fuel Pool Instrumentation RAI #7 Temperature Ratings for System Electronics Please provide informatiop in(licating a) the temperature ratings for all system electronics (including sensor electronics, system electronics, transmitter, receiver and display) and whether the rjitings are continuous duty ratings; and, b) what will be the maximum expected temperature and relative humidity conditi.ons in the room(s) in which the sensor electronics will be located under BOB [Beyond Design Basis] conditions i11 whiCh there will be no at power available to run Heati.ng Ventilation and Air Conditioning (HVAC) systems.

APS Response a) For components in the Auxiliary and Control Buildings, the sensor electronics are rated for minimum high temperature of 140°F at atmospheric pressure and a humidity of 0-100% (non-condensing). Other Spent Fuel Pool Instrumentation System (SFPIS) components located in the Auxiliary and Control Buildings (e.g.,

thos~ in the display cabinets) are rated for minimum high temperature of 140°F at atmospheric pressure and a humidity of o-95% (non-condensing).

Components (level sensor guided wave radar wire cable, Resistance Temperature Detector (RTD), and their respective interconnecting cables) in the Fuel Building are qualified for BOB conditions of 212°F at atmospheric pressure and 100%

humidity (saturated steam). All equipment is qualified for continuous duty.

b) The Control Room environment under BOB conditions has been evaluated to be a maximum temperature of <113°F (PVNGS Study 13-NS-A108, Reference 6 of this enclosure) with a relative humidity (RH) <75% (UFSAR Table 2.3-15, Reference 7 of this enc[osure) in equilibrium with outside air. For the Auxiliary Building Rooms A-302 and A-345, the PVNGS design conditions are considered to be bounding, with a maximum design temperature of 104°F (Table 3-2A of Auxiliary Building HVAC System (HA) System Design Basis Manual, Reference 8 of this enclosure). However, under BDB conditions, the temperatures in the Auxiliary Building rooms could be the same as the apjacent Control Room,

<113°F and< 75% RH in equilibrium with outside air (established in Study 13-NS-A108, PVNGS Engineering responses to INPO IER-11-4, Near-Term Actions to Address the Effects of an Extended Loss of All AC Power in Response to the Fukushima Daiichi Event).

13

Response to NRC RAis Regqrding Overall Integrated Plan for Implementation of 6ri;ler EA-12-051, Reliabl~ Spent Fuel Pool Instrumentation Order EA-12-051, Reliable Spent Fuel Pool Instrumentation* RAI #8 Evaluation of Sensor Electronics Design and Testing Please provide the following:

a) information describing the evaluation of the sensor electronics design, the shock test method, test re~;ults, and forces applied to the sen$o'r electronics applicable to its succf;!ss.ful tests demonstrating that the testing provide.s an appropriate. means to demonstrate reliability of the sensor electronics under the effects of severe shock.

b) inf.ormation describing ~he evaluation of the sensor electronics design, th~ vibration test method, test results, the forces and their frequency ranges and directions applied to the sensor applicable to its suc~essful tests, demonstrating that the testing provides an appropriate means to demonstrate reliability of the sensor electroili~s under the effects of high vibration.

APS Response a) The active electronic components of the Spent Fuel Pool Instrumentation System (Sf PIS) are firmly mounted inside NEMA-4X enclosures which are seismicaily qualified as detailed in documents JN350-A00076 (Reference 4 of this enclosure) and JN350-A00079 (Reference 5 of this encJosure). These housings are mounted to a seismically qualified wall ahd will not be subject to additional shock forces outside of those for seismic. The location selected was also reviewed for II/I (2/1) seismic and rotary equipment and missile generation impact. Therefore, no additional shock testing is required beyond Seismic Qualification Requirements as defined in IEEE 344-2004, IEEE Recommended Practice for Seismic Qualification of Cl~ss 1E Equipmt;nt for Nuclear Power Generating Stations.

The SFPIS equipment seismic adequacy is demonstrat~d based on the guidance in SectiOl1!? 7, 8, 9, anc;l 1d of IEEE 344-2004.

b) The active electronic components of the SFPIS are firmly mounted inside NEMA-4X enclosures. These enclosures are mounted to seisniically qualified walls and will not be ~ubject to additional vibration forces outside of those for seismic.

Therefore, no a.dditional vibration testing is required b~yond Seismic Qualification Requirements defined in IEEE 344-2004.

14

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation Order EA-i2-0S1. Reliable Spent Fuel Pool Instrumentation RAI #9 Analysis of Seismic Testing Results Please provide analysis of the seismic testing results and show that the instrument performance reliability, following e~posµre to simulated seismic conditions representative of the envirQnment anticipated for the SFP structures at Palo Verde, has been adequately demonstrated. Include information describing the design inputs and methodology used in any analyses of the mountings of electronic equipment ontQ plant structures, as requested in RAI #5 above.

APS Response The Spent Fuel Pool Instrumentation System (SFPIS), with the exception of the pool-side bracket, is qualified per IEEE 344-2004, IEEE Recommended Practice for Seismic Qualification of Class 1E Equipment for Nuclear Power Generating Stations. The objective of the testing and analysis was to demonstrate that the SFPIS meets the seismic performance requirements of JN350-A00078 (Reference 9 of this enclosure).

The Required Response Spectrum (RRS) for this program includes the 10% margin recommended by IEEE 323-2003, Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations. The seismic test and analysis results are documented in JN350-A00076 and JN350-A00079 (References 4 and 5, respectively of this enclosure). The pool-side bracket is qualified as Seismic Category I, per JN350-A00083 (Reference 2 of this enclosure).

15

Response to NRC RAis Regarding Overall Integrated *Plan for Implementation of Order EA-12,-051, Reliable Spent- Fuel Pool Instrumentation Order EA~12*051. Reliabl'!! Spent Fuel Pool 1n*strumentation RAI #10 Final Configuration of Power Supply Source Please prQvide the NRC staff with the final configuration of the power supply source for each channel so that the staff may conclude that the two channels are independent from a power supply assignment perspective.

APS Response The primary and alternate Spent Fuel Pool Instrumentation System (SFPIS) channels are powered by different Class AC buses. There are two Train~, each comprised of two Channels. for a total of four Channels. Train A is c;:omprised of Channels A and C, and Train B is comprised of Channels B and D. For the following equipment numbers x=the Unit, and is a 1, 2 or 3. The primary SFPIS channel receives its primary power from xEPNCD2726 (Train A, Channel C) which is powered from Class 1E Battery MCC

~EPKCM43 (Train A, ~hannel C). This Primary SFPIS channel receives its back-up power from xEPNDD2826 (Train B, Channel D) which is powered from Class 1E Battery MCC xEPKDM44 (Train B, Channel D). The alternate SFPIS channel receives its primary power from xEPNDD2826 (Train B, Channel D) powered from Class 1E Battery MCC xEPKDM44 (Train B, Channel D) with back-up power from xEPNCD2726

{Train A, Channel C) which is powered from Class 1E Bcittery MCC xEPKCM43 (Train A; Channel C). Primary and Back-up power sources for both the Primary and Backup Display Systems are isolated from each other through the use of manual Transfer

$witches xEPCNUOS and xEPCNU06, respectively.

Each SFPIS channel of equipment has an independent power supply and an independent Uninterruptible Power Supply (UPS) with 24V battery backup that ensures at least 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> of power without AC power, per the power consumption calculation JN350-A00081 (WNA-CN-00300-GEN, Reference 10 of this enclosure).

16-

Res.ponse to NRC RAis Regarding Overall Integrated Plan for ImplementC)tion of Order E:A-12-051, Re/fable Spent Fuel Pool Instru.mentation Order EA-12~os1, Reliable Spent Fuel Pool Instrumentation RAI #11 Electrical AC Power Sou~ces and Battery Backup Duty.Cycle Requirements Please provide the following:

a) A description of the electric:al ac power sources and capabiiities for the primary and backup channels.

b) Please provide ttle results of the calculation depicting ~he ba~ery backup duty cycle requirements d~~oostr~ting that it~ capacity is sufficient to maint~in the level indication function until offs.ite resource availability is reasonably assured.

APS Response.

a) For Local Electronics Enciosure xJPCNEOlS @rim~ry Display) the primary power is fed via exiSt:ing 120 VAC vital instrumentation and controls panel xEPNCD27 breaker 02726 (Train A, Channel C). The back-up power is 120 VAC vital instrumentation and controls pariel xEPNDD28 breaker 02826 (Train B, Channel D). The power source can be transferred from primary to backup via manual transfer switch xEPCNUOS.

Local Electronics Enclosure xJPCNE016 (Back-up Display) primary power is xEPNDD28 breaker 02826 {Train B, Channel D) and back-up power is xEPNCD27 breaker D2726 (Train A, Channel C). The power source for the Backup Display can be transferred from primary to backup via manual transfer switch xEPCNU06.

The 120 VAC vital instrumentcition panels xEPNCD27 and xEPNDD28 are normally fec;I from station class-lE batteries xEPKCF.13 and xEPKDF14; respectively, via inverters xEPNCN13 and xEPNDN14. The existing 120 VAC vital instrumentation and controls panels xEPNCD27 and xEPNDD28 also have a back-up AC source via voltage regulators xEPNCV27 and xEPNDV28.

Each Display Panel contains a 24 Voe UPS inverter. Upon loss of normal AC power this UPS Is used to feed the SFPIS electronics (i.e. indicator, di"splays, etc.). Power consumption calculation JN350-A00081 (Reference 10* of this enclosure) shows the UPS battery oack-up configuration identified in Table 1 will provide power for 5.07 days, which in excess of the 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> reqljired.

In th~ case of an extended loss of all AC power, the primary and ba.ckup SFPIS are powered from their respective l)PS until AC power is rest9red withrn 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

b) Table 1 is a summary of the calculation contained in the vendor document)N350-A00081 (Reference 10 of this* enclosure) demonstrating the capacity of the fully charged UPS is sj.Jfficient to maintain the SFPIS indication function for the stated 72 hpur requireme*nt of NEI 12-02, industry Guidance for Compliance with NRC Order EA-12-051, To Modify Li~enses with Regard to Relii!ble Spent FU<# Pool InstnJmentatfon. The c;:alculatiori results demonstrate a capacity of more than 126.

17

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation hours of operation for both the primary and backup SFPIS systems. The approximately 120 hours0.00139 days <br />0.0333 hours <br />1.984127e-4 weeks <br />4.566e-5 months <br /> UPS capacity provides sufficient margin for the SFP level indication to function until PVNGS transitions to Phase 2, as outlined in APS letter 102-06670 (Reference 11 of this enclosure). During Phase 2 operation, the SFPIS will be powered from an AC power source via the same inverters (xEPNCN13 and xEPNDN14) mentioned above while also recharging the SFPIS UPS. This alignment allows the instrumentation to function until an offsite resource is available.

Part# Description Amps Notes Loop powered device with 20mA MTSOOO Radar Level Sensor into transmitter 0.020 max current draw.

2864273 Temp. to 4-20 mA converter 0.021 per datasheet 1

Calculated based on idle load dissipation iri battery mode per 2320212 Uninterrupted Power Supply 0.054 datasheet. 1.3W/24V = 0.054A.

Rational, the normal load of 3.3W is at SA where the SFPIS is less than 0.5A.

2864176 4-20ma splitter - Level 0.030 Per datasheet, max.

2864176 4-20ma splitter - Temperature 0.030 Per datas.heet, max.

Per datasheet, 2 watts max. This calculates to 0.083 A. Not using 2864215 Digital Display - Level 0.053 the optional output (30mA).

0.083 A - 0.030 A = 0.053 A Per datasheet, 2 watts max. This calculates to 0.083 A. Not using 2864215 Digital Display - Temperature 0.053 the optional output (30mA).

0.083 A - 0.030 A = 0.053 A Average Consumption {Amps) 0.261 In accordance with Section 6.2.2 of Including Design Margin {100/o) 0.287 IEEE 485-2010 In accordance with Section 6.2.3 of Including Aging Margin {250/o) 0.359 IEEE 485-2010 Including Temperature Correction In accordance with Section 6.2.1 and 0.427 Table 1 of IEEE 485-2010 Factor@ 50 °F (190/o)

Amp Hours of 2320429 26.00 x 2 52.00 Battery Provided Total Hours Battery will last at Full 121.76 Charge Total Days Battery will Last at Full 5.07 Charge Table 1 18

Response to NR<;: RAis Regarding Overall Integrated Plan for Implementation of Orper EA-12-051, Re/fable Spent Fuel Pool Instrumentation Order EA-12-051. Reliable Spent Fuel Pool Instrumentation RAI #12 Instrument Channel Accuracy Performance and Maximum Allowed Deviation Please provide the foUowing:

a) An estimate of the expected instrument channel accuracy performance under both (a) normal SFP level conditions (appro>dmately Level 1 or higher) and (b) at the BDB conditions (i.e., radiation, temperature, humidity, post-seismic and po_st-shock conditions) th~t would be present if the SFP level were at the Level 2 and Level 3 datum points.

b) A de!['cription of the methodology that will be used for determining the maximum allowed deviation from the Instrument channel design accuracy that wi*ll be employed under l'.IOrmal operating conditions as an acceptance criterion for a calibration procedure to flag to operators and to technicians that the channel requires adjustment to within the normal condition design accuracy.

APS Response a) The channel accuracy for each Spent Fuel Pool Instrumentation System (SFPIS) instrument channel is+/- 3 inches for the full level measurement range which envelqpes level 1, 2, and 3 datum points. This covers the normal SFP surface level or higher to within six inches of the fuel assembly under both normal and BOB conditions. More details regarding the requirements on measurement accuracy are defined in the design specification document JN350-A00078 (Reference 9 of this enclosure) and the channel accuracy calculation document JN350-A00080 (Reference 12 of this enclosure).

• b) The channel accuracy requirements are identified in document JN350-A00078 (Reference 9 of this endosure) and demonstrated by the channel accuracy caltulation, JN350-A00080 (Reference 12 of this enclosure). NJ:I 12-02, Industry Guidance for Compliance with NRC Order EA-12-051, To Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation, and ISA-RP67 .04.02, Method9/ogies for the Determination of Set points for Nuclear Safety-Related Instrumentation, were used for calculating the overall channel accuracy.

Both SFP primary and backup redundant sensor electronics require periodic calibration verification to check that the channel's measurement performance is within the specified tolerance ( +/- 3 inches). If the difference Is larger than the allowable tolerance during the verification process, an electronic output verification/calibration will be required. If the electronic output verification/calibration does not restore the performance, a calibration adjustment will be required.

The electronic output v~rifi~ation/callbration will verify electronics are working properly using simulated probe signals.

19

Response to NRt RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Re/ipble Spent Fuel Pool Instrumentation The calibration adjustment is performed to restore level measurement accuracy within the acceptance criteria at 0%, 25%, 50%, 75%, and 100% points of the full span. The calibration acceptance criteria and procedures are defined in JN350-A00077 (Reference 13 of this ~nclosure).

The calibration verification ls an empirical two-point check using the sliding bracket calibration verification method in Section 2.2 of document JN350-A00077 (Reference 13 of this enclosure) or the fixed bracket caJibration verification method in Section 2.3 of document JN350-A00077 (Reference 13 of this enclosure). These methods use different level positions to verify the sensor and sensor electronics are in proper working order to detect level differences. This check is to be completed within 60 days of a planned refu,eling outage, considering normal testing scheduling allowances (e.g., 25%). This check is not required to be performed mcire than once per 12 months per NEI 12-02, Industry Guidance for Compliance with NRC Order EA-12-051, To Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation.

20

Response to NRC RAis Regarding Overall Integrated Plan for Implementation.

of Order EA-12-0S;L, Reliable.Spent Fuel Poof Instrumentation Order EA-12-0Si, Reliable Spent Fuel Pool Instrumentation RAI #13 Level Sensing Equipment Capability. Testing, Fu'nctional Checks, and Maintenance Tasks Please provide the following:

a) A desc.ript.ion of th.e capability and provisicm~ the proposed level sensing equipment will have to enable periodic testing and calibration, including how this capability enables the equipment to be tested in-situ.

b) A description of how such testing and calibration will enable the conduct of regular channel checl!e along the expected travel p~th.

The maximum estimated dose rate to an <;>perator is predicted to be less than 15 mRem per hour during this evolution arid well within the quarterly limits of 10 CFR

20. . '

The alternate display location eriVironmental conditions (temperature and humidity),

following a BOB event, would be very similar to the conditions at the primary SFP level instrumentation display, in the Main Control Room. The location on the 140 foot elevation of the Auxiliary Building is near the emergency plan Operation Support Center (OSC) and the normal Radiological Controlled Area {RCA) access ,point Personnel Will not be continuously stationed at the <;lisplay location.; it will be monitored periodically as determined necessary by the Control Room ~taff. Refe'rence RAI #7 response for additional details regarding environrnentcil conditions.

23.

Response to NRt RAIS Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Inst1ymentation Order EA-12-051, Reliable Spent Fuel Pool Instrumentation RAI #15 List of Procedures Please provide a list of the procec;lures addressing. operation {both no_rmal and abnormal response), caiibration, t;est, maintenance, and inspection procedures th~t will be developed for use of the spent SFP instrumentC1tioi1.

The licensee is requested to include a brief description of the specific technical objectives to be achieved within each procedure.

APS Respon~e Normal operation of the Spent Fuel Pool Instrumentation System {SFPIS) is addressed in Procedure 400P-9PC06, Spent Fuel Pool Operations. Guidance is provided in the procedure for placing the SFPIS in service, transferring power between the normal and b13ckup power supplies and removing the SFPIS from service.

There are no specific abnormal operations required for theSFPIS. However the SFPIS is one of the level instruments to be considered when determining the Entry Conditions for abnormal operating procedure 40A0-9ZZ23, Loss of SFP Level or Cooling.

• Calibration and testing of the two SFPIS channels (primary and alternate) are performed using 36MT-9FH01, Spent Fuel Pool Instrumentation System Level and Temperature Calibration Check - Primary and 36MT-9FH02, Spent Fµel Pool Instrumentation System Level and Temperature Calibration Check - Alternate. These procedures are based on information from JN350-A00077 (Reference 13 of this enclosure), Spent Fuel Instrumentation System Calibration Procedure, which contains the calibration and test procedures, the periodic calibration verification checks, and periodic maintenance checks for the probes. These procedures ensure that the SFPIS will retain its accuracy as defined by the design specification d_ocument JN350-A00078 (Reference 9 of this enclosure), the NRC Order {EA 051) and NEI guidance (NEI 12-02, Industry Guidance for Compliance with NRC Order EA-12-051, To Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation) as clarified by the interim staff guidance JLD-ISG-2012-03 (Reference 14 of this enclosure) Compliance with Order EA-12-051> Reliable Spent F_uel Pool Instrumentation.

Inspection and verification of SFPIS op~rati6n are addressed in the nightly Control Room surveillances. The seven surveillance procedures are mode specific and are -

listed as follows:

40ST-9ZZM1, Operations Mode 1 Surveillance Logs 40ST-9ZZM2, Operations Mode 2 Surveillance Logs 40ST,.9ZZM3, Operations Mode 3 Surveillance Logs 40ST-9ZZM4, Operations Mode 4 Surveillance Logs 40ST-9ZZM,5, Operations Mode 5 Surveillance logs 40ST-9ZZM6, Operations Mode 6 Surv~illance Logs 40Sl-9ZZM7, Operations DefL}eled Surveillance Logs 24

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Poof Instrumentation The procedures include a nightly check of the system including comparison with existing level systems and guidance for required action(s) should a channel(s) be found non-functional. Additionally, the area operator logs include a nightly check of the indicators located in the Auxiliary Building to verify proper operation and notification to the Control Room if the system is not functioning as expected. The area logs are Procedures 40DP-90PA3, Area 3 Operator Logs, Modes 1-4 and 40DP-90PB1, Primary Operator Logs, Modes 5, 6 and Defue!ed.

JN350-A00082 (Reference 16 of this enclosure) contains instructions for installation, normal operation, abnormal response/troubleshooting, cleaning, calibration, maintenance, spare parts, and special tools for the SFPIS, as well as the major components of the system. This document was used to develop the above listed procedures.

25

Response to NRC RAis Rt;!garding Overal.1 Integrated Plan for Impler'nentgtion

• of Order EA-12-051, R~/if!bfe.$pent i=uel Pool Instrumentation

. Order EA-12-051, Rel_iaf>.le Spent Fuel Poo~ Instrumentation RAl: #16 Maintenance and Testing Program and In-Situ Calibration Process Please provide the following:

a) Fum:-tl}er information describing the m_ainten~nce and t~sting program th~

licensee will establish and implement *to .en~ure th.at regular testing and calibration is performed and verified by inspection and audit to

~emonstrate conforma_nce \!llith design *an_~ systern readiness requirements. Inelude a description of'your plans for ens1,1ring that necessary channel checks, functional tests, periodic calibratlo'n; and maintenance will be conducted fo.r the level meas1,.1rement system an.d its supp*orting eqµipment.

b) A description of the in-situ calibration proce~s at the SFP locat.io~ that will resuit in th~ c"-annel calibration being maintained at its design accuracy.

APS Response a) The maint¢nance and testing* program will ensures that regular testing and calibration are performed and verified*, Calibration and testing for the instruments

• are based on SDOC JN350-A00077 (Reference 13 of this enclosure) as adapted to specific site procedures. Con~urrent with calibration activities, maintenance activities include partially extracting the level probe from the pool for inspection to ensure no frays or nicks have occurred since the last verification check, and to remove ariy significant accum4ICJtion of boron where the probe tran*sitions from water to air.

Site specific procedures define the periodicity for Operator rounds to compare the primary and backup instrument channel indications to existing SFP level instrumentation to determine if nior'e immediate action is required for calibration, maintenance or compensatory action in:tplement!=ltion. The periodic calibration verification check is performed within 60 day~ of a planned refuel_ing outage considering normal testing scheduling allowances (e.g., 25°19).

b) The sensor electronics module (l.e., transmitt;er) has electronic verification/calibration capaqilities to check for correct signal output and verify correct level in~trument loop operation.

If the verification/calibration indicates that the instrur(ient loop is operating out bf specifications or an anomaly is observed, then a full range calibratfon adjustment is performed l.,fsing a calibration test kit. The test kit is used with the sensor elettronics mod.ule to perform a full range calibration. The test kit consists of a replicate probe, coupler, launch plate, sfrm.ilated pool liner, coax signal cable, and a movable target prate (to simulate water level). The probe, coupler, launch plate and coax ,Signal cable is equivalent to the instaii~d equipment in the SFP area.

The full range calibration can be performed inside/outside of the SFP area.

26

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation The calibration verification, electronic output verification/calibration, and the calibration adjustment are defined in SDOC JN350-AOOD77 (Reference 13 of this enclosure).

27

Response to NR~ RAis Regarding Overall Integrated. Plan for implementation

.of Order EA-12-0Si, Relial:)le Spent Fuel Pool Instrumentation References

1. Jl'.11350-A00010 (Document 10116D46), Spent Fµel Pool Instrumentation System Instrumentatipn Resistance temperature Detector (RTDj Procurement

2. JN350-AOQ083 (CN,..f>Eus:.13..,26), Seismic Analysis of the Spent fuel Pool Mounting Bracket for the Palo Verde Nut/ear Plant

3. Westinghouse Letter-SST-13-2, Rev. 1, Software R~/ease Letter for GTSTRUDL 32 for the XP and XP64 System States. §eorgia Iech STRUctural Design 1,anguage (GTSTRl)DL). A finite element analysis compute code, Georgia Tech Research Corporation.

4. JN350-A00076 (Document EQ-QR-269), Design Verification Testing Summary Report for the Spent Fuel Pool Instrumeritation System *

5. JN3!?0-A00079 (Document WNA-TR~03149-GEN), SFPIS Standard Product Final Summary Design Verification Report

6. S.tudy 13-NS-A108, PVNGS Engineering Responses.to INPO IER-11-4

7. UFSAR Ta~le 2.3-15

8. Design Basis Manual (HA), Auxiliary Building HVAC System, Table 3.:.2A, Auxiliary Building Normal Air Handling Units-(AHUs), 13.:.M-HAN-AOlA & B

9. JN350-A00078 (WNA-DS-02957-GEN), Nuclear Automation Spent Fuel Pool

[nstrumentation Systems Standard Production Non-$afety Augmented Quality De$ign Specification

10. JN350-A00081 (Document WNA-CN-00300-GEN), Spent Fuel Pool Instrumentation System Power Consumption Calculation

11. APS Letter 102-06670, APS Overall Integrated Plan in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated February 28, 2013

12. JN350-A00080 (WNA-CN-00301-GEN), Spent Fuel Pool Instrum~ntation System Channel Accuracy Analysis

13. JN350-AOOQ77 (WNA-TP-04709-t;;EN), Spent Fuel Pool InstrumentC;Jtion System Calibration Procedure

14. Interim Staff Guidance JLD-ISG-2012-03, Compliance with Order EA-12-051, Order Modifying Licenses With Regard to Reliable Spent Fuel Pool Instrumentation

15. APS letter to NRC 102-06728, Palo Verde Nuclear Gen~rating Station (PVNGS)

Units 1, 2, and 3 Docket Nos. STN 5()-528, 50-529, and 50-53 Response to Request for Additional Information for the PVNGS Overall Integrated Plan in Response to March 12, 2012 Commission Order Modifying Licen$es with Regard to Relir;Jble Spent Fuel Pool Level Instrumentation (Order Number EA-12~051), dated July 11, 2013

16. ji\J350-A00082 (Document WNA-G0-00127-GEN), Spent Fuel Pool Instrumentation Systt;!m Techn.ical Manual

17. JN350-AOQ038 (Drawing 10067E04)1 Spent Fuel POCJI Primary and Backup Instrumentation Mounting Brac.kets Plan, S~ctions and Details 28

Response to NRC RAis RegardJng Overall Integrated Plan for Implementation

. of Order EA-12-051, Reliable Spent Fuel Poql Instrumentation RAI Number: None (Additional information reauesteci by the NRC Staff on Phone call on S/15/2014)

Staff question (transmitted by Email May 1~, 2014)

From: Boska, John To: Kelsey, David H "EMI: This is a f~llow up question that we will have with all vendors

~sing Westinghouse Electric Company (WEC). We kn~w th.at the WEC instrument was tested and passed EMI testing to a level B. That means that some signals could preclude the instrument from working but once that signal is gone, the instrument is goo~. We j~st want the information from the licensee where they tell us what actions they are tak_ing to m.a.ke sure no signal will interfere with th~ instrument when it is needed. This could be something added to a procedure or a line painted around the area where no walkie-talkie~ are allowed, spmething along those li.nes. It might not evei:i be an i.ssue because of

- tile location of the instrument, and if that's the case then we just need them to tell us."

APS Response APS has completed the following actions to minimize the potential for Electromagnetic Interference (EMI) interference:

1. A caution ?ign has been posted at the Spent Fuel Pool Instrumentation System (SFPIS) electronic compon~nts {local electronics enclosures) which are located on the 140 foot elevation of the Auxiliary Building adjacent to the Radiation Protection (RP) Island. Also, caution signs have been posted at the

~AO foot elevation of the primary and alternate readout module locations in the Control Rc:iom envelope and Auxiliary Building, respectively.

2. op*erators are briefed in general training on the susceptibility of various plant equipment to EMI.

3. Design Verification Testing (DVT) was performed after installation in one PVNGS unit within the Fuel Building, to assess the potential for EMI impacts on essential equipment operation, such as the probe, bare guide wave cable aiid connectors. Since PVNGS is implementing the SFPIS with the 'stilling well' protection feature, no EMI interference was expected or encountere<f. As a result of the DVT, APS has determined that no additional actions are warranted.

1 The stilling well Is a 3-lnch diameter 299-lnch long Schedule 40 stainless steel tube which is welded to the launch plate and extends Into the pool. The Level Sensor' probe drops Into the pool and Is inside the tube. The stilling well serves both to shield the probe from EMI and to reduce any wave effects on the probe that might occur due to sloshing In the pool.

29

EA-12,-051 Oaps MARI~ L, LACAL Senior Vice President Nuclear Regulatory and Over-Sight Palo Verde Nuclear Generating Station P.O. Box 52034 Phoenix, AZ 85072 Mali Station 7605 102-07248-MLL/TNW/PJH Tel 623.39~:6491 April 29, 2016 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk 11555 Rockville Pi~e Rockville, MD 20852

References:

1. NRC Order Number EA-12-051, Order Modit'ying Licenses with Regard to Reliable Spent.Pue/ Pool L'eve/ Instrumentation, dated March 12, 20;1.2 .

2. NRC Letter, Palo Verde Nuclear Generating Station, Units 1, 2, and 3 - Interim Staff !;valuation and Request tor Additional Information (RAI) Regarding Overall Integrated Plan for Implementation of Order EA-12-051, "Reliable Spent Fuel Pool Instrumentation (SFPI)," dated October 29, 2013

3. NRC Email, NRC Staff Request for FLEX $FPI Information, dated May 13, 2014

4. NRC Email, NRC Request to Docket Palo Verde FLEX SFPI RAis, dated March 19, 2016

Dear Sirs:

Subject:

Palo Verde Nuclear G~nerating Station (PVNGS)

Units 1, 2, and 3 Docket Nos. STN 50-528, 50-529, and 50-530 APS Response to Request for Additional Information Regarding Overall Integrated Plan for Implementation of Order EA 051, Reliable Spent Fuel Pool lnstrumentai:ion On March 12, 2012, the Nuclear R~gulatory Commission (NRC) issued an order (Reference 1) to Arizona Public Service Company (APS). Reference 1 was immediately effective and directed that PVNGS must have a reliable means of remotely monitoring Wide-range Spent Fuel Pool (SFP) levels to support effective

• prioritization of event mitigation and recovery actions in the event of a beyond-design-b~sis ~xternal event. Specific requirements are outlined in Attachment 2 of Reference 1.

The NRC issued PVNGS Interim Staff Evaluation {IS!:) and RAI regarding the overaU integrated plan. for implementation of Order EA-12-051 in Reference 2. These RA!

responses were provided in the electronic reading room. The enclosure to this letter contains the APS responses to the NRC RAis contained in References 3 and 4. These RAI responses have been updated to reflect current practices and/or configuration information.

A member of the STARS (Strategic Teaming and Resource Sharing)

Callaway

• Diablo Canyon

• Palo Verde

• Wolf Creek

102-07248-MLL/TNW/PJH ATTN: Do~ument Control Desk U.S. Nuclear Regulatory Commission

~PS Response to RAis Reg~rding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation Page 2 No commitments are being made to the NRC by this letter.

Should you have any questions concerning the content of this letter, please contact Mike Dilorenzo, Section Leader, Nuclear Regulatory Affairs, at (623) 393-3495.

I declare under penalty of perjury that the foregoing is true anq c:orrect.

Executed on APtZ-1 L 2 0/ '2.0/ t/;

(Date)

Sincer~ly, MLL/TNW/PJH/af

Enclosure:

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation cc: M. L. Dapas NRC Region IV Regional Administrator S. P. Lingam NRC NRR Project Manager for PVNGS M. M. Watford NRC NRR Project Manager C. A. Peabody NRC Senior Resident Inspector far PVNGS J.P. Boska NRC NRR/JLD/PPSD/JOMB Project Manager A member of the STAR8 (Strategic Teaming and Resource Sharing) Alliance Callaway

• Diablo Canyon

• Palo Verde

• Wolf creek

ENCLOSURE Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order ~A-12-051, R.~liable Spent fuel Pool Instrumentation INTRODUCTION On March 12, 2012, the U.S. Nuclear R~gulatory Commission (NRC) issued Order EA-12-051, Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation [Agencywide Documents Access and Management System (ADAMS)

Accession No. ML12054A679], to all power reactor licensees and holders of construction permits in active status. This order required licensees to have a reliable indication of the water level in associated spent fuel storage pools capabl~ of supporting identification of the following pool water level conditions by trained personnel: ( 1) level that is adequate to support operation of the normal fuel pool cooling system, (2) level that is adequate to provide substantial radiation shielding for a person standing on the Spent Fuel Pool operating deck, and (3) level where fuel remains covered and actions to implement make-up water addition should no longer be deferred.

By letter dated February 28, 2013 (ADAMS Accession No. ML13070A077), Arizona Public Service Company (APS) provided the Overall Integrated Plan (OIP) for the Palo Verde Nuclear Generating Station {PVNGS) describing how compliance with of Order EA-12-051 would be achieved; by fall 2014 for Unit 1, fall 2015 for Unit 2, and spring 2015 for Unit 3 .. By letter dated June 10, 2013 (ADAMS Accession No. ML13157A065), the NRC staff provided a request for additional information (RAJ) to APS. Supplemental information was provided to the NRC by APS letter nu.mbers 102-06728 dated July 11, 2013 (ADAMS Accession No. ML13199A033), and 102-06759 dated August 28, 2013 {ADAMS Accession No. ML13246A008). By letter dated October 29, 2013 (ADAMS Accession No. ML13296A006), the NRC staff provided a request for additional information (RAI) to AP5j. NRC Email, dated March 23, 2016, requested the RAI responses be docketed.

This enclosure contains the APS response to the RAis regarding Reliable Spent Fuel Pool Instrumentation updated to reflect current practices *and/or configuration Information. The NRC staff introductory information in the October 29, 2013 letter, related to the background for the RAis, is not included in this enclosure. The request for information is restated, followed by the AP~ response.

1

Respon*se to NRC ~Is Regarding {)vercill Integrated Plan for Implementation of Order EA-12-~05i, Re!iiJl;J/e spent Fuel Pool Instrurnentation Order EA-12-051. Rel_iable Spent Fuel Pool Instrumentation RAI #i DescriDtion of Other SFP Structures Please j>tovjde tf~e followiil~:

a) A description of h.ow the other structures in ~he vicinity of the SFPs (cask loading pit, transfe*r canals and *gates) shown iil Figure *2, "Spent Fuel P.ool Geometry and Dimen.sions;' are conn*ected to the SFPs.

• b) If additional structures, other than the SFP~ i.n each unit, are used for fuel storage, d~scribe in detail their usage, operation, and provide ju~tifications for not installing s.eparate level instrl.iineritation in other*

structures used for fuel storage.

APS Response a) The Spent Fuel Pool (SFP) is connected to two refueling structures; the Transfer Canal and the Cask Loading Pit, reference Figure 1. A Seismic Category I gate, with dual seals separates the inventory betwe~n the SFP and the Cask Loading Pit. A Seismic Category I gate and seal separ~tes the inventory between the SFP artd the Transfer Canal. This seal is currently being modified to a dual seal design independent of Order EA-12-051. In addition, a Seismic Category I gate, with dual seals, separates the inventory between the Cask Loading Pit and the Cask Decontamination Pit, which connect:S to the Fuel Building at grade elevation. This gate is only removed during dry cask campaign? when the gate between the SFP and Cask Loading Pit is installei;I. The lowest elevation of the gate between the Cask Loading Pit and the c;ask Decontamination Pit is 124 feet, O inches which is above the tpp of the SFP storage rack (114 feet, 2 inches). The dual gate seals are pressurized by a redundant, air ahd nitrogen gas supply and have an additional Seismic Category I back,.up nitrogen source~ The SFP is configured to comply with the requirements of Regulatory Gµide l.i.3, Spent Fuel Storage Facility Design Basis, Revision 0.

b) The independent spent fuel storage installation (ISFS~) is designed to store PVNGS irradiated spent nuclear fuel. The ISFSI consists of twelve large rectangular concrete pads. The concrete storage pads are apprqximately 285 feet Icing by 35 feet wide and are situated In a 3-pad by 4-pad array. Each storage pad is designed to accommodate 28 spent fuel storage.casks arranged in two parallel rows of i4 casks. NAC international Inc. (NAC) was selected as the cask

?Ystem supplier for Palo Verde. The NAC spent fuel cask system is_ a canister-based design for storage of sp~nt nuclear fuel. After the ta.sl!:p' TRUE NORTI!

SPENI' FUEL POOL CASK LOADING OECON PIT GATE GATE CASK DECONrA.WNAllO PIT FIJEL (NEW)

!NSPECllON PIT 1~

Plan Vjew Figure 1 3

Response to NRC RAis Regard ing Overall Integrated Plan for Implementation of Order EA 051 , Reliable Spent Fuel Pool Instrumentation Order EA-12-051. Reliable Spent Fuel Pool Instrumentation RAI #2 Summary of Proposed Wireless Technology Please provide your plant-specific performance evaluation result and a brief summary of the proposed wireless technology that will be used in the primary and backup measurement systems to address the criteria summarized in Section 3.1 of NEI 12-02.

APS Response PVNGS opted to use hardwired SFP level measurement systems instead of wireless, for both the primary and alternate systems installed in each SFP. The hardwired

" system for level instrumentation meets each of the requirements of Section 3.1 of NEI 12-02, Industry Guidance for Compliance with NRC Order EA-12-051 , "To Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation."

4

Response t o NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA- 12-051, Reliable Spent Fuel Pool Instrumentation Order EA- 12-051. Reliable Spent Fuel Pool Instrumentation RAI #3 Primary and Back-Up SFP Level Sensor Please provide the following:

a) The final locations/placement of the primary and back- up SFP level sensor.

b) Additional information describing how the proposed arrangement of the sensor probe assembly and routing of the cabling between the sensor probe assembly and the electronics in the Auxiliary Building meets the Order requirement to arrange the SFP level instrument channels in a manner that provides reasonable protection of the level indication function against missiles that may result from damage to the structure over the SFP.

APS Response a) The primary instrument channel sensor Is mounted in accordance with JN350-A00038 (Reference 17 of th is enclosure) in the northeast corner of the SFP on th e east wall. The back-up (alternat e) instru ment channel sensor is located in the southeast corner of the Spent Fuel Pool (SFP) on the south wall, as shown in Figure 2.

b) Physica l separation of the primary and alternate Instrument channel signal cables and power cables is maintained using train separation requirements identified in PVNGS Specification 13-EN-0611, Installation Specification for Reg. Guide 1.75 Cable and Raceway Separation. The IEEE Standards for the Level Sensor Coaxial Signal Cable are IEEE 323-2003, IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations, and IEEE 383-2003, IEEE Standard for Qualifying Class 1 E Electric Cables and Field Splices for Nuclear Power Generating Stations.

The Resistance Temperatu re Detector {RTD} Cables meet the requirements of IEEE-572- 1985, IEEE Standard for Qualification ofClass 1£ Connection Assemblies for Nuclear Power Generating Stations, IEEE- 383- 1974, IEEE Standard for Type Test of Class 1 E Electric Cables, Field Splices, and Connections for Nuclear Power Generating Stations, and IEEE - 1202- 1991, IEEE Standard for Flame Testing of Cables for Use in Cable Tra y in Industrial and Commercial Occupancies, as shown on document JN350-A00010 (Reference 1 of th is enclosure) .

The sensors are located close to th e side walls of the SFP and below the floor elevation to utilize the pool walls as inherent protection . From the primary sensor, the primary signal cable, contained in rigid metal conduit , is run east along the floor to the east wall of the Fuel Building . The primary signal cable is t hen routed along the east wall until it penetrates the wall into the Aux iliary Bu ilding. From the alternate sensor, the alternate signa l cable, contained in rigid metal conduit, is run east along the fl oor to the east wall of t he Fuel Building. The alternate signal cable is then routed along the east wall until it penetrat es the 5

Response to NRC RAIS Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation wall into the Auxil iary Building. The raceway containing the signal cables share only a small distance along the common east wall of the Fuel Building where they penetrate the wall and enter the Auxiliary Building .

Once the cables enter the Auxil iary Building they are routed to separate locations prior to connecting to the electronics. The SFP walls and comers provide inherent missile protection for the level sensor cable. See Figure 2 for a depiction of the conduit routing.

The Fuel and Auxili ary Buildings are classified as Seismic Category I structures designed to remain intact and functional following a Safe Shutdown Earthquake (SSE) or Operating Basis Earthquake (OBE) event. The inherent design function of the structures precludes any part of the building structure from falling or becoming a missile during/after a seismic event. Seismic Category I components attached to the building structures are designed to the same requirements as the structures and will remain intact and functional following an

• SSE or OBE event. Non-Seismic Category I components are also attached to the bui lding structures. These components are classified as Seismic Category IX and are designed to remain intact following an SSE event. Seismic Category IX components are not required to rema in functional and can deform but are designed to preclude falling or becoming a missile during/after a seismic event.

Additionally, Seismic Category I structures are designed for, and protected against, the effects of internal and external missiles. The missiles considered were both tornado-generated (external) and internally-generated (i.e., turbine missiles). For each potential missile, its origin, size, impact velocity or energy, and direction were considered . Seismic Category I structures were analyzed for these values per the analysis and design guidelines of Bechtel Topical Report BC-TOP-9A, Design of Structures for Missile Impact, UFSAR Section 3.5, Missile Protection, and UFSAR Appendix 3C, Design of Structures for Tornado Missile Impact. Missile-resistant barriers and structures were designed to withstand and absorb missUe impact loads in order to prevent damage to protected structures, systems, and components.

Tornado missile protection for Seism ic Category I structures, other than the Containment Building, is provided by the following exterior wall and roof thicknesses:

• Walls : Minimum 21 inches (f' c = 4000 lb./in 2 )

• Roofs: Minimum 16 inches (f' c = 5000 lb./in 2 )

6

Response to NRC RAis Regard ing Overall Integrated Plan for Implementation of Order EA-12-05 1, Reliable Spent Fuel Pool Instrumentation Back-up (alternate) instrument channel sensor location Primary instrument channel sensor location

- - - Primary

- - - Alternate Routing of Sensor Cables from Sensor Location to Display Locations Figure 2 7

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order l;:A-12-051, Reliable Spent Fuel Pool Ins.trumenta~ipn Order EA-12-051, Reliable Spent Fuel Pool Instrumentation RAI #4 Seismic Testing of the Sensor Probe Assembly Please provide the analyses verifyfog that the seismic testing of the sensor probe assembly and the ele.ctronics units, and the licensee's analysis of the combined maximum seismic and hydrodyn~mic forces on the sensor probe assembly exposed to the potentiaf sloshing effects, show that the SFP instrument design configuration will be maintained during and following the maximum seismic ground motion considered in the design of the SFP structure.

APS Response Level Sensor Bracket: The mounting bracket for the sensing pro~e was designed according to the plant design basis for Safe Shutdown Earthquake (SSE) seismic hazard curve at the pool deck elevation, as documented in JN350-A00083 (Reference 2 of this enclosure). Loads that were considered in the evaluation of the bracket and its mounting are: *

(1) Static loads including the dead weight of the mounting bracket in addition to the weight of the level sensing instruments, stilling well and cabling; (2) Dynamic loads including the seismic load due to excitation of the instruments dead weight in addition to the hydrodynamic effects resulting from the excitation of the SFP water.

A response spectra analysis was performed for the seismic evaluation of the mounting bracket using GTSTRUDL (Reference 3 of this enclosure). Hydrodynamic effects on the mounting bracket were evaluated using Technical Report Nuclear Reactors and Earthquakes, TID-7024, dated August 196;3 and added to the GTSTRUDL model. Plant acceptance criteria and applicable codes were used for the design of the bracket and Its anchorage.

Results were shown to be adequate for the loads and load combinations used in the analysis. Welded and bolted connections were evaluated and were shown to be adequate. The base plate of the mounting bracket and the anchorage to the concrete were evaluated using Plate Wizard in GTSTRUDL and designed to meet the plant criteria for base plates and anchors.

Spent Fuel Pool Instrumentation System CSFPISl Equipment {sensor and electronics): The seismic testing for the Sensor and Electronics is documented in JN350-A00076 (Reference 4 of this enclosure). The seismic testing was satisfied for SSE in accordance with IEEE 344-2004, IEEE Recommended Practice for Seismic Qualification of Class 1E Equipment for Nuclear Power Generating Stations, Required Response Spectra (RRS) to IEEE 323-2003 with 10% margin included. SSE is shown in Figure 3. The Operating Basis Earthquake (OBE) RRS at 5% critical damping was at least 70% of the respective SSE seismic level of Figure 3.

The sensor and electronics met each of the required performance and acceptance criteria, maintained structural integrity during the acceptable SSE test runs, and acceptaple QBE test runs to the RRS. Acceptable functionality of the electronics and 8

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation sensor was confirmed upon completion of seismic testing. In accordance with the requirements of JN350-A00076 (Reference 4 of this enclosure), testing included five successful OBE tests and two successful SSE tests. The post-test .inspection, performed upon completion of the seismic tests, revealed no major structural issues or damage.

SFPIS DBE and SSE Required Response Spectrum

• 5% Critical Damping 1 10 100 Frequency (HZ)

SFPIS OBE and SSE RRS for all Principal Directions at 50/o Critical Damping (100/o Margin Included)

Figure 3 9

Response to NRC RAis Regarding Overall Integrated l?l'an for Implementation of Order EA-12-051, Reliable Spent Fuel Pool jnstrumentation Order EA...12-051. Reliable Spent Fuel Pool Instrumentation RAI #5 Mounting Attachments for SFP Level Equipment For each of the mounting attachments required to attach SFP Level equipment to plant structures, please describe the design iraputs, and the methodology that was used to qualify the st.ructural integrity of the affect~d structures/ equipment.

APS Response The design input and qualification methodology is consistent with the current seismic design for existing plant structures/equipment.

• With the exception of the level sensor probe mounting bracket which was qualified by analysis, all the system equipment is seismically qualified by testing. The outputs of the seismic test of equipment were used as the design input for the qualification of the mounting of that specific equipment.

The sensing prope mounting bracket was designed accordin*g to the plant design basis for Safe Shutdown Earthquake (SSE) or Operating Basis Earthquake (OBE) at the appropriate plant elevation. In order to ensure adequate design margin for the SSE and OBE events, the seismic inputs were increased by 10%. The following loads that were considered in the evaluation of the bracket and its mounting:

(1) Static loads including the dead weight of the mounting bracket in addition to the weight of the level sensing instruments, stilling well and cabling; (2) Dynamic loads including the seismic load due to excitation o(the dead weight of the system in addition to the hydrodynamic effects resulting from the excitation of the SFP water.

A response Spectra analysis was performed for the seismic evaluation of the mounting bracket using GTSTRUDL software (Reference 3 9f this enclosure) and using floor response spectrum at the operating deck elevation as identified in the PVNGS UFSAR Revision 17 and the Palo Verde Design Basis Manual CS, Revision 4, Seismic Topical. Hydrodynamic effects on the mounting bracket were evaluated using Technical Report Nuclear Reactor~ and Earthquakes, TID-7024, dated August 1963. Plant acceptance criteria and applicable codes were used for the design of the bracket and its anchorage. Evaluations of support members and connections showed a design margin of 10% or more (JN,350-A0.0083, Reference 2 of this enclosure).

The seismic testing for the sensor electronics bracket is documented in JN350-A00076 (Reference 4 of this enclosure). The seismic testing was satisfied by performing seismic testing to the SSE in accordance with IEEE 344-2004. The Required Response Spectra (RRS) in accordance with IEEE 323-2003 Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations including a 10% margin.

10

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation

• order EA-12-051. Reliabie Spent Fuel Pool.Instrumentation RAI #6 Radiological Conditions at Equipment Location Please provide analysis of the maximum expected radiological conditions (dose rate and total integrated d~se) to which the equipment located within the control building or AB [Auxiliary Building] will be exposed. Also, please provide documentation indicating the radiological dosage amount that the electrQnics for this equipment is capable of withstanding. Please di.scuss the time period over which the analyzed total integrated dose was applied.

APS Response During a beyond-design-basis external event (BDBEE) it is expected that conditions in the Auxiliary and Control Buildings are consistent with the normal operating conditions established in the PVNGS Equipment Qualification (EQ) Program Manual.

For the Auxiliary Building Total Integrated Dose (TIO) for a 40 year period is 1.00 E0.6 Rads gamma at the location of the subject instrumentation. TIO for the 140 foot of the Control Building is not identified in the EQ Program Manual as it is considered a mild environment. Mild environment conditions are those occurring during normal plant operation (all modes), including any abnormal operating occurrence. For the Auxiliary Building and Control Building, all areas with instrumentation dose rates are typically <0*.2 mRem per hour.

A summary of the radiological conditions to which the equipment is qualified is provided below.

Radiological conditions for the Spent Fuel Pool Instrumentation System (SFPIS) components in the SFP area:

The coaxial cable, the c<;>upler, the p<;>ol-side bracket, and the probe In the SFP area will operate reliably in the seniice environmental conditions specified in the table below.

Parameter Normal*, Beyond Design Basis*

Radiation TIO 1.00 E03 Rads (above pool) aamma 1.00 E07 Rads gamma R9diation TIO 1.00 E09 Rads

(.12" above top of fuel gamma rack) (probe & weiaht onM LOO E07 Rads gamma

• Per Table 4. L2-1 of JN350-A00079 (Reference 5 of this enclosure) and Table 4.8-1 of JN350-A00078 (Referem;e 9 of this enclosure)

The SFP area radiological conditions are detailed In JN350-A00079 (Referen!=e 5 of this enclosure).

• 11

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation Radiological conditions outside of the SFP area:

The level sensor electronics (i.e., transmitter), sensor electronics bracket, indicators, and the electronics enclosures outside of the SFP area are required to operate reliably in the service environmental conditions specified in the table below.

Beyond Design Parameter Normal**

Basis**

Radiation TID ~ 1E03 Rads gamma ~ 1E03 Rads qamma

• • Per Table 4.1.3-1 of JN350-A00079 (Reference 5 of this enclosure) and Table 4.8-2 of JN350-A00078 (Reference 9 of this enclosure)

\

I 12

R,esponse to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable spent Fuel Pool Instrumentation Order EA-12-051. Reliable Sqent Fuel Pool Instrumentation RAI #7 Temperature Ratings for System Electronics Please provide informatiop in(licating a) the temperature ratings for all system electronics (including sensor electronics, system electronics, transmitter, receiver and display) and whether the rjitings are continuous duty ratings; and, b) what will be the maximum expected temperature and relative humidity conditi.ons in the room(s) in which the sensor electronics will be located under BOB [Beyond Design Basis] conditions i11 whiCh there will be no at power available to run Heati.ng Ventilation and Air Conditioning (HVAC) systems.

APS Response a) For components in the Auxiliary and Control Buildings, the sensor electronics are rated for minimum high temperature of 140°F at atmospheric pressure and a humidity of 0-100% (non-condensing). Other Spent Fuel Pool Instrumentation System (SFPIS) components located in the Auxiliary and Control Buildings (e.g.,

thos~ in the display cabinets) are rated for minimum high temperature of 140°F at atmospheric pressure and a humidity of o-95% (non-condensing).

Components (level sensor guided wave radar wire cable, Resistance Temperature Detector (RTD), and their respective interconnecting cables) in the Fuel Building are qualified for BOB conditions of 212°F at atmospheric pressure and 100%

humidity (saturated steam). All equipment is qualified for continuous duty.

b) The Control Room environment under BOB conditions has been evaluated to be a maximum temperature of <113°F (PVNGS Study 13-NS-A108, Reference 6 of this enclosure) with a relative humidity (RH) <75% (UFSAR Table 2.3-15, Reference 7 of this enc[osure) in equilibrium with outside air. For the Auxiliary Building Rooms A-302 and A-345, the PVNGS design conditions are considered to be bounding, with a maximum design temperature of 104°F (Table 3-2A of Auxiliary Building HVAC System (HA) System Design Basis Manual, Reference 8 of this enclosure). However, under BDB conditions, the temperatures in the Auxiliary Building rooms could be the same as the apjacent Control Room,

<113°F and< 75% RH in equilibrium with outside air (established in Study 13-NS-A108, PVNGS Engineering responses to INPO IER-11-4, Near-Term Actions to Address the Effects of an Extended Loss of All AC Power in Response to the Fukushima Daiichi Event).

13

Response to NRC RAis Regqrding Overall Integrated Plan for Implementation of 6ri;ler EA-12-051, Reliabl~ Spent Fuel Pool Instrumentation Order EA-12-051, Reliable Spent Fuel Pool Instrumentation* RAI #8 Evaluation of Sensor Electronics Design and Testing Please provide the following:

a) information describing the evaluation of the sensor electronics design, the shock test method, test re~;ults, and forces applied to the sen$o'r electronics applicable to its succf;!ss.ful tests demonstrating that the testing provide.s an appropriate. means to demonstrate reliability of the sensor electronics under the effects of severe shock.

b) inf.ormation describing ~he evaluation of the sensor electronics design, th~ vibration test method, test results, the forces and their frequency ranges and directions applied to the sensor applicable to its suc~essful tests, demonstrating that the testing provides an appropriate means to demonstrate reliability of the sensor electroili~s under the effects of high vibration.

APS Response a) The active electronic components of the Spent Fuel Pool Instrumentation System (Sf PIS) are firmly mounted inside NEMA-4X enclosures which are seismicaily qualified as detailed in documents JN350-A00076 (Reference 4 of this enclosure) and JN350-A00079 (Reference 5 of this encJosure). These housings are mounted to a seismically qualified wall ahd will not be subject to additional shock forces outside of those for seismic. The location selected was also reviewed for II/I (2/1) seismic and rotary equipment and missile generation impact. Therefore, no additional shock testing is required beyond Seismic Qualification Requirements as defined in IEEE 344-2004, IEEE Recommended Practice for Seismic Qualification of Cl~ss 1E Equipmt;nt for Nuclear Power Generating Stations.

The SFPIS equipment seismic adequacy is demonstrat~d based on the guidance in SectiOl1!? 7, 8, 9, anc;l 1d of IEEE 344-2004.

b) The active electronic components of the SFPIS are firmly mounted inside NEMA-4X enclosures. These enclosures are mounted to seisniically qualified walls and will not be ~ubject to additional vibration forces outside of those for seismic.

Therefore, no a.dditional vibration testing is required b~yond Seismic Qualification Requirements defined in IEEE 344-2004.

14

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation Order EA-i2-0S1. Reliable Spent Fuel Pool Instrumentation RAI #9 Analysis of Seismic Testing Results Please provide analysis of the seismic testing results and show that the instrument performance reliability, following e~posµre to simulated seismic conditions representative of the envirQnment anticipated for the SFP structures at Palo Verde, has been adequately demonstrated. Include information describing the design inputs and methodology used in any analyses of the mountings of electronic equipment ontQ plant structures, as requested in RAI #5 above.

APS Response The Spent Fuel Pool Instrumentation System (SFPIS), with the exception of the pool-side bracket, is qualified per IEEE 344-2004, IEEE Recommended Practice for Seismic Qualification of Class 1E Equipment for Nuclear Power Generating Stations. The objective of the testing and analysis was to demonstrate that the SFPIS meets the seismic performance requirements of JN350-A00078 (Reference 9 of this enclosure).

The Required Response Spectrum (RRS) for this program includes the 10% margin recommended by IEEE 323-2003, Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations. The seismic test and analysis results are documented in JN350-A00076 and JN350-A00079 (References 4 and 5, respectively of this enclosure). The pool-side bracket is qualified as Seismic Category I, per JN350-A00083 (Reference 2 of this enclosure).

15

Response to NRC RAis Regarding Overall Integrated *Plan for Implementation of Order EA-12,-051, Reliable Spent- Fuel Pool Instrumentation Order EA~12*051. Reliabl'!! Spent Fuel Pool 1n*strumentation RAI #10 Final Configuration of Power Supply Source Please prQvide the NRC staff with the final configuration of the power supply source for each channel so that the staff may conclude that the two channels are independent from a power supply assignment perspective.

APS Response The primary and alternate Spent Fuel Pool Instrumentation System (SFPIS) channels are powered by different Class AC buses. There are two Train~, each comprised of two Channels. for a total of four Channels. Train A is c;:omprised of Channels A and C, and Train B is comprised of Channels B and D. For the following equipment numbers x=the Unit, and is a 1, 2 or 3. The primary SFPIS channel receives its primary power from xEPNCD2726 (Train A, Channel C) which is powered from Class 1E Battery MCC

~EPKCM43 (Train A, ~hannel C). This Primary SFPIS channel receives its back-up power from xEPNDD2826 (Train B, Channel D) which is powered from Class 1E Battery MCC xEPKDM44 (Train B, Channel D). The alternate SFPIS channel receives its primary power from xEPNDD2826 (Train B, Channel D) powered from Class 1E Battery MCC xEPKDM44 (Train B, Channel D) with back-up power from xEPNCD2726

{Train A, Channel C) which is powered from Class 1E Bcittery MCC xEPKCM43 (Train A; Channel C). Primary and Back-up power sources for both the Primary and Backup Display Systems are isolated from each other through the use of manual Transfer

$witches xEPCNUOS and xEPCNU06, respectively.

Each SFPIS channel of equipment has an independent power supply and an independent Uninterruptible Power Supply (UPS) with 24V battery backup that ensures at least 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> of power without AC power, per the power consumption calculation JN350-A00081 (WNA-CN-00300-GEN, Reference 10 of this enclosure).

16-

Res.ponse to NRC RAis Regarding Overall Integrated Plan for ImplementC)tion of Order E:A-12-051, Re/fable Spent Fuel Pool Instru.mentation Order EA-12~os1, Reliable Spent Fuel Pool Instrumentation RAI #11 Electrical AC Power Sou~ces and Battery Backup Duty.Cycle Requirements Please provide the following:

a) A description of the electric:al ac power sources and capabiiities for the primary and backup channels.

b) Please provide ttle results of the calculation depicting ~he ba~ery backup duty cycle requirements d~~oostr~ting that it~ capacity is sufficient to maint~in the level indication function until offs.ite resource availability is reasonably assured.

APS Response.

a) For Local Electronics Enciosure xJPCNEOlS @rim~ry Display) the primary power is fed via exiSt:ing 120 VAC vital instrumentation and controls panel xEPNCD27 breaker 02726 (Train A, Channel C). The back-up power is 120 VAC vital instrumentation and controls pariel xEPNDD28 breaker 02826 (Train B, Channel D). The power source can be transferred from primary to backup via manual transfer switch xEPCNUOS.

Local Electronics Enclosure xJPCNE016 (Back-up Display) primary power is xEPNDD28 breaker 02826 {Train B, Channel D) and back-up power is xEPNCD27 breaker D2726 (Train A, Channel C). The power source for the Backup Display can be transferred from primary to backup via manual transfer switch xEPCNU06.

The 120 VAC vital instrumentcition panels xEPNCD27 and xEPNDD28 are normally fec;I from station class-lE batteries xEPKCF.13 and xEPKDF14; respectively, via inverters xEPNCN13 and xEPNDN14. The existing 120 VAC vital instrumentation and controls panels xEPNCD27 and xEPNDD28 also have a back-up AC source via voltage regulators xEPNCV27 and xEPNDV28.

Each Display Panel contains a 24 Voe UPS inverter. Upon loss of normal AC power this UPS Is used to feed the SFPIS electronics (i.e. indicator, di"splays, etc.). Power consumption calculation JN350-A00081 (Reference 10* of this enclosure) shows the UPS battery oack-up configuration identified in Table 1 will provide power for 5.07 days, which in excess of the 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> reqljired.

In th~ case of an extended loss of all AC power, the primary and ba.ckup SFPIS are powered from their respective l)PS until AC power is rest9red withrn 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

b) Table 1 is a summary of the calculation contained in the vendor document)N350-A00081 (Reference 10 of this* enclosure) demonstrating the capacity of the fully charged UPS is sj.Jfficient to maintain the SFPIS indication function for the stated 72 hpur requireme*nt of NEI 12-02, industry Guidance for Compliance with NRC Order EA-12-051, To Modify Li~enses with Regard to Relii!ble Spent FU<# Pool InstnJmentatfon. The c;:alculatiori results demonstrate a capacity of more than 126.

17

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation hours of operation for both the primary and backup SFPIS systems. The approximately 120 hours0.00139 days <br />0.0333 hours <br />1.984127e-4 weeks <br />4.566e-5 months <br /> UPS capacity provides sufficient margin for the SFP level indication to function until PVNGS transitions to Phase 2, as outlined in APS letter 102-06670 (Reference 11 of this enclosure). During Phase 2 operation, the SFPIS will be powered from an AC power source via the same inverters (xEPNCN13 and xEPNDN14) mentioned above while also recharging the SFPIS UPS. This alignment allows the instrumentation to function until an offsite resource is available.

Part# Description Amps Notes Loop powered device with 20mA MTSOOO Radar Level Sensor into transmitter 0.020 max current draw.

2864273 Temp. to 4-20 mA converter 0.021 per datasheet 1

Calculated based on idle load dissipation iri battery mode per 2320212 Uninterrupted Power Supply 0.054 datasheet. 1.3W/24V = 0.054A.

Rational, the normal load of 3.3W is at SA where the SFPIS is less than 0.5A.

2864176 4-20ma splitter - Level 0.030 Per datasheet, max.

2864176 4-20ma splitter - Temperature 0.030 Per datas.heet, max.

Per datasheet, 2 watts max. This calculates to 0.083 A. Not using 2864215 Digital Display - Level 0.053 the optional output (30mA).

0.083 A - 0.030 A = 0.053 A Per datasheet, 2 watts max. This calculates to 0.083 A. Not using 2864215 Digital Display - Temperature 0.053 the optional output (30mA).

0.083 A - 0.030 A = 0.053 A Average Consumption {Amps) 0.261 In accordance with Section 6.2.2 of Including Design Margin {100/o) 0.287 IEEE 485-2010 In accordance with Section 6.2.3 of Including Aging Margin {250/o) 0.359 IEEE 485-2010 Including Temperature Correction In accordance with Section 6.2.1 and 0.427 Table 1 of IEEE 485-2010 Factor@ 50 °F (190/o)

Amp Hours of 2320429 26.00 x 2 52.00 Battery Provided Total Hours Battery will last at Full 121.76 Charge Total Days Battery will Last at Full 5.07 Charge Table 1 18

Response to NR<;: RAis Regarding Overall Integrated Plan for Implementation of Orper EA-12-051, Re/fable Spent Fuel Pool Instrumentation Order EA-12-051. Reliable Spent Fuel Pool Instrumentation RAI #12 Instrument Channel Accuracy Performance and Maximum Allowed Deviation Please provide the foUowing:

a) An estimate of the expected instrument channel accuracy performance under both (a) normal SFP level conditions (appro>dmately Level 1 or higher) and (b) at the BDB conditions (i.e., radiation, temperature, humidity, post-seismic and po_st-shock conditions) th~t would be present if the SFP level were at the Level 2 and Level 3 datum points.

b) A de!['cription of the methodology that will be used for determining the maximum allowed deviation from the Instrument channel design accuracy that wi*ll be employed under l'.IOrmal operating conditions as an acceptance criterion for a calibration procedure to flag to operators and to technicians that the channel requires adjustment to within the normal condition design accuracy.

APS Response a) The channel accuracy for each Spent Fuel Pool Instrumentation System (SFPIS) instrument channel is+/- 3 inches for the full level measurement range which envelqpes level 1, 2, and 3 datum points. This covers the normal SFP surface level or higher to within six inches of the fuel assembly under both normal and BOB conditions. More details regarding the requirements on measurement accuracy are defined in the design specification document JN350-A00078 (Reference 9 of this enclosure) and the channel accuracy calculation document JN350-A00080 (Reference 12 of this enclosure).

• b) The channel accuracy requirements are identified in document JN350-A00078 (Reference 9 of this endosure) and demonstrated by the channel accuracy caltulation, JN350-A00080 (Reference 12 of this enclosure). NJ:I 12-02, Industry Guidance for Compliance with NRC Order EA-12-051, To Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation, and ISA-RP67 .04.02, Method9/ogies for the Determination of Set points for Nuclear Safety-Related Instrumentation, were used for calculating the overall channel accuracy.

Both SFP primary and backup redundant sensor electronics require periodic calibration verification to check that the channel's measurement performance is within the specified tolerance ( +/- 3 inches). If the difference Is larger than the allowable tolerance during the verification process, an electronic output verification/calibration will be required. If the electronic output verification/calibration does not restore the performance, a calibration adjustment will be required.

The electronic output v~rifi~ation/callbration will verify electronics are working properly using simulated probe signals.

19

Response to NRt RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Re/ipble Spent Fuel Pool Instrumentation The calibration adjustment is performed to restore level measurement accuracy within the acceptance criteria at 0%, 25%, 50%, 75%, and 100% points of the full span. The calibration acceptance criteria and procedures are defined in JN350-A00077 (Reference 13 of this ~nclosure).

The calibration verification ls an empirical two-point check using the sliding bracket calibration verification method in Section 2.2 of document JN350-A00077 (Reference 13 of this enclosure) or the fixed bracket caJibration verification method in Section 2.3 of document JN350-A00077 (Reference 13 of this enclosure). These methods use different level positions to verify the sensor and sensor electronics are in proper working order to detect level differences. This check is to be completed within 60 days of a planned refu,eling outage, considering normal testing scheduling allowances (e.g., 25%). This check is not required to be performed mcire than once per 12 months per NEI 12-02, Industry Guidance for Compliance with NRC Order EA-12-051, To Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation.

20

Response to NRC RAis Regarding Overall Integrated Plan for Implementation.

of Order EA-12-0S;L, Reliable.Spent Fuel Poof Instrumentation Order EA-12-0Si, Reliable Spent Fuel Pool Instrumentation RAI #13 Level Sensing Equipment Capability. Testing, Fu'nctional Checks, and Maintenance Tasks Please provide the following:

a) A desc.ript.ion of th.e capability and provisicm~ the proposed level sensing equipment will have to enable periodic testing and calibration, including how this capability enables the equipment to be tested in-situ.

b) A description of how such testing and calibration will enable the conduct of regular channel checl!e along the expected travel p~th.

The maximum estimated dose rate to an <;>perator is predicted to be less than 15 mRem per hour during this evolution arid well within the quarterly limits of 10 CFR

20. . '

The alternate display location eriVironmental conditions (temperature and humidity),

following a BOB event, would be very similar to the conditions at the primary SFP level instrumentation display, in the Main Control Room. The location on the 140 foot elevation of the Auxiliary Building is near the emergency plan Operation Support Center (OSC) and the normal Radiological Controlled Area {RCA) access ,point Personnel Will not be continuously stationed at the <;lisplay location.; it will be monitored periodically as determined necessary by the Control Room ~taff. Refe'rence RAI #7 response for additional details regarding environrnentcil conditions.

23.

Response to NRt RAIS Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Inst1ymentation Order EA-12-051, Reliable Spent Fuel Pool Instrumentation RAI #15 List of Procedures Please provide a list of the procec;lures addressing. operation {both no_rmal and abnormal response), caiibration, t;est, maintenance, and inspection procedures th~t will be developed for use of the spent SFP instrumentC1tioi1.

The licensee is requested to include a brief description of the specific technical objectives to be achieved within each procedure.

APS Respon~e Normal operation of the Spent Fuel Pool Instrumentation System {SFPIS) is addressed in Procedure 400P-9PC06, Spent Fuel Pool Operations. Guidance is provided in the procedure for placing the SFPIS in service, transferring power between the normal and b13ckup power supplies and removing the SFPIS from service.

There are no specific abnormal operations required for theSFPIS. However the SFPIS is one of the level instruments to be considered when determining the Entry Conditions for abnormal operating procedure 40A0-9ZZ23, Loss of SFP Level or Cooling.

• Calibration and testing of the two SFPIS channels (primary and alternate) are performed using 36MT-9FH01, Spent Fuel Pool Instrumentation System Level and Temperature Calibration Check - Primary and 36MT-9FH02, Spent Fµel Pool Instrumentation System Level and Temperature Calibration Check - Alternate. These procedures are based on information from JN350-A00077 (Reference 13 of this enclosure), Spent Fuel Instrumentation System Calibration Procedure, which contains the calibration and test procedures, the periodic calibration verification checks, and periodic maintenance checks for the probes. These procedures ensure that the SFPIS will retain its accuracy as defined by the design specification d_ocument JN350-A00078 (Reference 9 of this enclosure), the NRC Order {EA 051) and NEI guidance (NEI 12-02, Industry Guidance for Compliance with NRC Order EA-12-051, To Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation) as clarified by the interim staff guidance JLD-ISG-2012-03 (Reference 14 of this enclosure) Compliance with Order EA-12-051> Reliable Spent F_uel Pool Instrumentation.

Inspection and verification of SFPIS op~rati6n are addressed in the nightly Control Room surveillances. The seven surveillance procedures are mode specific and are -

listed as follows:

40ST-9ZZM1, Operations Mode 1 Surveillance Logs 40ST-9ZZM2, Operations Mode 2 Surveillance Logs 40ST,.9ZZM3, Operations Mode 3 Surveillance Logs 40ST-9ZZM4, Operations Mode 4 Surveillance Logs 40ST-9ZZM,5, Operations Mode 5 Surveillance logs 40ST-9ZZM6, Operations Mode 6 Surv~illance Logs 40Sl-9ZZM7, Operations DefL}eled Surveillance Logs 24

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Poof Instrumentation The procedures include a nightly check of the system including comparison with existing level systems and guidance for required action(s) should a channel(s) be found non-functional. Additionally, the area operator logs include a nightly check of the indicators located in the Auxiliary Building to verify proper operation and notification to the Control Room if the system is not functioning as expected. The area logs are Procedures 40DP-90PA3, Area 3 Operator Logs, Modes 1-4 and 40DP-90PB1, Primary Operator Logs, Modes 5, 6 and Defue!ed.

JN350-A00082 (Reference 16 of this enclosure) contains instructions for installation, normal operation, abnormal response/troubleshooting, cleaning, calibration, maintenance, spare parts, and special tools for the SFPIS, as well as the major components of the system. This document was used to develop the above listed procedures.

25

Response to NRC RAis Rt;!garding Overal.1 Integrated Plan for Impler'nentgtion

• of Order EA-12-051, R~/if!bfe.$pent i=uel Pool Instrumentation

. Order EA-12-051, Rel_iaf>.le Spent Fuel Poo~ Instrumentation RAl: #16 Maintenance and Testing Program and In-Situ Calibration Process Please provide the following:

a) Fum:-tl}er information describing the m_ainten~nce and t~sting program th~

licensee will establish and implement *to .en~ure th.at regular testing and calibration is performed and verified by inspection and audit to

~emonstrate conforma_nce \!llith design *an_~ systern readiness requirements. Inelude a description of'your plans for ens1,1ring that necessary channel checks, functional tests, periodic calibratlo'n; and maintenance will be conducted fo.r the level meas1,.1rement system an.d its supp*orting eqµipment.

b) A description of the in-situ calibration proce~s at the SFP locat.io~ that will resuit in th~ c"-annel calibration being maintained at its design accuracy.

APS Response a) The maint¢nance and testing* program will ensures that regular testing and calibration are performed and verified*, Calibration and testing for the instruments

• are based on SDOC JN350-A00077 (Reference 13 of this enclosure) as adapted to specific site procedures. Con~urrent with calibration activities, maintenance activities include partially extracting the level probe from the pool for inspection to ensure no frays or nicks have occurred since the last verification check, and to remove ariy significant accum4ICJtion of boron where the probe tran*sitions from water to air.

Site specific procedures define the periodicity for Operator rounds to compare the primary and backup instrument channel indications to existing SFP level instrumentation to determine if nior'e immediate action is required for calibration, maintenance or compensatory action in:tplement!=ltion. The periodic calibration verification check is performed within 60 day~ of a planned refuel_ing outage considering normal testing scheduling allowances (e.g., 25°19).

b) The sensor electronics module (l.e., transmitt;er) has electronic verification/calibration capaqilities to check for correct signal output and verify correct level in~trument loop operation.

If the verification/calibration indicates that the instrur(ient loop is operating out bf specifications or an anomaly is observed, then a full range calibratfon adjustment is performed l.,fsing a calibration test kit. The test kit is used with the sensor elettronics mod.ule to perform a full range calibration. The test kit consists of a replicate probe, coupler, launch plate, sfrm.ilated pool liner, coax signal cable, and a movable target prate (to simulate water level). The probe, coupler, launch plate and coax ,Signal cable is equivalent to the instaii~d equipment in the SFP area.

The full range calibration can be performed inside/outside of the SFP area.

26

Response to NRC RAis Regarding Overall Integrated Plan for Implementation of Order EA-12-051, Reliable Spent Fuel Pool Instrumentation The calibration verification, electronic output verification/calibration, and the calibration adjustment are defined in SDOC JN350-AOOD77 (Reference 13 of this enclosure).

27

Response to NR~ RAis Regarding Overall Integrated. Plan for implementation

.of Order EA-12-0Si, Relial:)le Spent Fuel Pool Instrumentation References

1. Jl'.11350-A00010 (Document 10116D46), Spent Fµel Pool Instrumentation System Instrumentatipn Resistance temperature Detector (RTDj Procurement

2. JN350-AOQ083 (CN,..f>Eus:.13..,26), Seismic Analysis of the Spent fuel Pool Mounting Bracket for the Palo Verde Nut/ear Plant

3. Westinghouse Letter-SST-13-2, Rev. 1, Software R~/ease Letter for GTSTRUDL 32 for the XP and XP64 System States. §eorgia Iech STRUctural Design 1,anguage (GTSTRl)DL). A finite element analysis compute code, Georgia Tech Research Corporation.

4. JN350-A00076 (Document EQ-QR-269), Design Verification Testing Summary Report for the Spent Fuel Pool Instrumeritation System *

5. JN3!?0-A00079 (Document WNA-TR~03149-GEN), SFPIS Standard Product Final Summary Design Verification Report

6. S.tudy 13-NS-A108, PVNGS Engineering Responses.to INPO IER-11-4

7. UFSAR Ta~le 2.3-15

8. Design Basis Manual (HA), Auxiliary Building HVAC System, Table 3.:.2A, Auxiliary Building Normal Air Handling Units-(AHUs), 13.:.M-HAN-AOlA & B

9. JN350-A00078 (WNA-DS-02957-GEN), Nuclear Automation Spent Fuel Pool

[nstrumentation Systems Standard Production Non-$afety Augmented Quality De$ign Specification

10. JN350-A00081 (Document WNA-CN-00300-GEN), Spent Fuel Pool Instrumentation System Power Consumption Calculation

11. APS Letter 102-06670, APS Overall Integrated Plan in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated February 28, 2013

12. JN350-A00080 (WNA-CN-00301-GEN), Spent Fuel Pool Instrum~ntation System Channel Accuracy Analysis

13. JN350-AOOQ77 (WNA-TP-04709-t;;EN), Spent Fuel Pool InstrumentC;Jtion System Calibration Procedure

14. Interim Staff Guidance JLD-ISG-2012-03, Compliance with Order EA-12-051, Order Modifying Licenses With Regard to Reliable Spent Fuel Pool Instrumentation

15. APS letter to NRC 102-06728, Palo Verde Nuclear Gen~rating Station (PVNGS)

Units 1, 2, and 3 Docket Nos. STN 5()-528, 50-529, and 50-53 Response to Request for Additional Information for the PVNGS Overall Integrated Plan in Response to March 12, 2012 Commission Order Modifying Licen$es with Regard to Relir;Jble Spent Fuel Pool Level Instrumentation (Order Number EA-12~051), dated July 11, 2013

16. ji\J350-A00082 (Document WNA-G0-00127-GEN), Spent Fuel Pool Instrumentation Systt;!m Techn.ical Manual

17. JN350-AOQ038 (Drawing 10067E04)1 Spent Fuel POCJI Primary and Backup Instrumentation Mounting Brac.kets Plan, S~ctions and Details 28

Response to NRC RAis RegardJng Overall Integrated Plan for Implementation

. of Order EA-12-051, Reliable Spent Fuel Poql Instrumentation RAI Number: None (Additional information reauesteci by the NRC Staff on Phone call on S/15/2014)

Staff question (transmitted by Email May 1~, 2014)

From: Boska, John To: Kelsey, David H "EMI: This is a f~llow up question that we will have with all vendors

~sing Westinghouse Electric Company (WEC). We kn~w th.at the WEC instrument was tested and passed EMI testing to a level B. That means that some signals could preclude the instrument from working but once that signal is gone, the instrument is goo~. We j~st want the information from the licensee where they tell us what actions they are tak_ing to m.a.ke sure no signal will interfere with th~ instrument when it is needed. This could be something added to a procedure or a line painted around the area where no walkie-talkie~ are allowed, spmething along those li.nes. It might not evei:i be an i.ssue because of

- tile location of the instrument, and if that's the case then we just need them to tell us."

APS Response APS has completed the following actions to minimize the potential for Electromagnetic Interference (EMI) interference:

1. A caution ?ign has been posted at the Spent Fuel Pool Instrumentation System (SFPIS) electronic compon~nts {local electronics enclosures) which are located on the 140 foot elevation of the Auxiliary Building adjacent to the Radiation Protection (RP) Island. Also, caution signs have been posted at the

~AO foot elevation of the primary and alternate readout module locations in the Control Rc:iom envelope and Auxiliary Building, respectively.

2. op*erators are briefed in general training on the susceptibility of various plant equipment to EMI.

3. Design Verification Testing (DVT) was performed after installation in one PVNGS unit within the Fuel Building, to assess the potential for EMI impacts on essential equipment operation, such as the probe, bare guide wave cable aiid connectors. Since PVNGS is implementing the SFPIS with the 'stilling well' protection feature, no EMI interference was expected or encountere<f. As a result of the DVT, APS has determined that no additional actions are warranted.

1 The stilling well Is a 3-lnch diameter 299-lnch long Schedule 40 stainless steel tube which is welded to the launch plate and extends Into the pool. The Level Sensor' probe drops Into the pool and Is inside the tube. The stilling well serves both to shield the probe from EMI and to reduce any wave effects on the probe that might occur due to sloshing In the pool.

29