ML15351A449

Notification of Full Compliance with NRC Orders EA-12-049 and EA-12-051 for Unit 2

ML15351A449
Person / Time
Site:	Palo Verde
Issue date:	12/17/2015
From:	Lacal M Arizona Public Service Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
102-07157-MLL/TNW, EA-12-049, EA-12-051
Download: ML15351A449 (18)

Text

EA-12-049 EA-12-051 Maria L. Lacal Vice President, Nuclear Regulatory & Oversight Palo Verde Nuclear Generating Station P.O. Box 52034 Phoenix, AZ 85072 Mail Station 7605 Tel 623.393.6491 102-07157-MLL/TNW December 17, 2015 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk 11555 Rockville Pike Rockville, MD 20852

References:

1. NRC Order Number EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events, dated March 12, 2012

2. NRC Order Number EA-12-051, Order Modifying Licenses with Regard to Requirements for Reliable Spent Fuel Pool Instrumentation, dated March 12, 2012

Subject:

Palo Verde Nuclear Generating Station (PVNGS)

Units 1, 2, and 3 Docket Nos. STN 50-528, 50-529, and 50-530 Notification of Full Compliance with NRC Orders EA-12-049 and EA-12-051 for PVNGS Unit 2 On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued orders regarding mitigation strategies for beyond design bases external events and reliable spent fuel pool instrumentation (References 1 and 2).

Reference 1 required full implementation of mitigating strategies for beyond design basis external events no later than two refueling cycles after submittal of the Overall Integrated Plan (OIP) or December 31, 2016, whichever comes first. Reference 2 required full implementation of reliable spent fuel pool instrumentation no later than two refueling cycles after submittal of the OIP or December 31, 2016, whichever comes first. The orders also directed that achievement of full compliance be reported to the Commission.

This letter with the enclosure fulfills the requirement of the orders to report to the Commission that full compliance with the referenced orders has been achieved in PVNGS Unit 2. The enclosure provides a brief summary of the key elements associated with compliance to the orders. The attachment to the enclosure provides a high level summary response for each of the open and pending items being tracked by the NRC staff with regard to the orders. This letter also fulfills the requirement of the orders to report to the Commission that full compliance with the referenced orders has been achieved for PVNGS Units 1, 2, and 3. The Final Integrated Plan A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway

• Diablo Canyon

• Palo Verde

• Wolf Creek

102-07157-MLL/TNW ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Notification of Full Compliance with NRC Orders EA-12-049 and EA-12-051 for PVNGS Unit 2 Page 2 (FIP) reflecting the strategies for PVNGS Units 1, 2, and 3 is being submitted via separate letter.

No commitments are being made to the NRC by this letter.

Should you have any questions concerning the content of this letter, please contact Thomas Weber, Department Leader, Regulatory Affairs, at (623) 393-5764.

I declare under penalty of perjury that the foregoing is true and correct.

Executed on December 17, 2015 (Date)

Sincerely, Digitally signed by Lacal, Lacal, Maria Maria L(Z06149)

DN: cn=Lacal, Maria L(Z06149)

L(Z06149)

Date: 2015.12.17 10:22:13

-07'00' MLL/TNW/PJH/af

Enclosure:

PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051) cc: M. L. Dapas NRC Region IV Regional Administrator M. M. Watford NRC NRR Project Manager for PVNGS C. A. Peabody NRC Senior Resident Inspector for PVNGS J. P. Boska NRC NRR/JLD/JOMB Project Manager

ENCLOSURE PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

1. Introduction Arizona Public Service Company (APS) developed an Overall Integrated Plan (OIP)

(Reference 1) to provide diverse and flexible strategies (FLEX) in response to Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Reference 2). The information provided herein, as well as the implementation of the OIP, documents compliance with Order EA-012-049 for Palo Verde Nuclear Generating Station (PVNGS) Unit 2.

APS also developed an OIP (Reference 3) to address reliable spent fuel pool (SFP) instrumentation in response to Order EA-12-051 Order Modifying Licenses with Regard to Requirements for Reliable Spent Fuel Pool Instrumentation (Reference 4).

The information provided herein, as well as the implementation of the OIP, documents compliance with Order EA-012-051 for PVNGS Unit 2.

The full compliance with the referenced orders has been achieved for PVNGS Units 1, 2, and 3.

2. Open Item Resolution Issues from the NRC Interim Staff Evaluation (ISE) (Reference 5) and Audit Report (Reference 6) have been addressed by APS. The issues that were identified as open and pending in the NRC tracking system are listed below:

ISE Open Item (ISE OI) - ISE OI 3.1.1.2.A ISE Confirmatory Items (ISE CI) - ISE CI 3.2.2.A and 3.2.4.10.A Licensee Identified Open Items - PVNGS has no open or pending licensee identified open items.

Audit Questions/Audit Report Open/Pending Items - Items RAI-2-B, RAI-14-B, RAI-27-B, SE-4 (1)-(b), SE-6, SE-8, RAI-33-B and RAI-34-B A summary of the response to each of the issues is provided in the attachment to this enclosure. The open and pending items do not affect the compliance of Unit 2 to Order EA-012-049 or Order EA-012-051.

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

3. Milestone Schedule - Items Complete Unit 2 FLEX and SFPI Unit 2 FLEX Unit 2 SFPI Milestone Completion Date Completion Date Submit Overall Integrated Plan February 2013 February 2013 Submit 6 Month Updates:

Update 1 August 2013 August 2013 Update 2 February 2014 February 2014 Update 3 August 2014 August 2014 Update 4 February 2015 February 2015 Update 5 August 2015 August 2015 FLEX Strategy Evaluation September 2013 N/A Perform Staffing Analysis June 2014 N/A 1

Modifications:

Modifications Final Design Completion November 2014 July 2014 Unit 2 Final Modification Implementation October 2015 October 2015 Storage:1 Storage Design Engineering Completion March 2014 N/A Storage Implementation April 2015 N/A FLEX Equipment: 1 Procure On-Site Equipment April 2015 December 2014 1

Milestone actions were completed prior to Unit 2 Cycle 19 startup on November 14, 2015.

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

4. Order EA-12-049 Compliance Elements Summary The elements identified below for PVNGS Unit 2 as well as the FLEX OIP (Reference 1), the 6-Month Status Reports (References 7, 8, 9, 10, and 11) and additional docketed correspondence, demonstrate compliance with Order EA-12-049.

Strategies - Complete PVNGS Unit 2 strategies are in compliance with Order EA-12-049.

There are no strategy related Open Items, Confirmatory Items, or Audit Questions/Audit Report Open Items.

Modifications - Complete The modifications required to support the FLEX strategies for PVNGS Unit 2 have been fully implemented in accordance with the station processes.

Equipment - Procured and Maintenance & Testing - Complete The equipment required to implement the FLEX strategies for PVNGS Unit 2 has been procured, received at PVNGS, initially tested and performance verified as recommended in accordance with NEI 12-06, Diverse and Flexible Coping Strategies (FLEX) Implementation Guide and is available for use.

Maintenance and testing requirements are included in the PVNGS Preventative Maintenance Program such that equipment reliability is monitored and maintained.

Protected Storage - Complete The storage facility required to implement the FLEX strategies for PVNGS Unit 2 has been constructed and provides adequate protection from the applicable site hazards. The equipment required to implement the FLEX strategies for PVNGS Unit 2 is stored in its protected configuration.

The Units 1, 2, 3, and N+1 equipment have been moved into their final storage facility.

Procedures - Complete FLEX Support Guidelines (FSGs) for PVNGS Unit 2 have been developed and integrated with existing procedures. The FSGs and applicable procedures have been verified and are available for use in accordance with the site procedure control program.

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

Training - Complete Training for PVNGS Unit 2 has been completed in accordance with an accepted training process, as recommended in NEI 12-06, Diverse and Flexible Coping Strategies (FLEX) Implementation Guide.

Staffing - Complete The PVNGS Phase 2 staffing study for PVNGS (Reference 12) has been completed in accordance with 10 CFR 50.54(f) letter (Reference 13).

The NRC has reviewed the Phase 2 staffing study and concluded that it adequately addresses the response strategies needed to respond to a beyond design basis external event using Palo Verde procedures and guidelines. This is documented in NRC letter dated September 29, 2014 (Reference 14).

National Safer Response Centers - Complete APS has established a contract with Pooled Equipment Inventory Company (PEICo) and has joined the Strategic Alliance for FLEX Emergency Response (SAFER) Team Equipment Committee for off-site facility coordination. It has been confirmed that PEICo is ready to support PVNGS with Phase 3 FLEX equipment stored in the National SAFER Response Centers in accordance with the site specific SAFER Response Plan.

Validation - Complete APS has completed validation in accordance with industry developed guidance to assure required tasks, manual actions and decisions for FLEX strategies are feasible and may be executed within the constraints identified in the FLEX OIP for Order EA-12-049 (References 1 and 2).

FLEX Program Document - Established The APS PVNGS FLEX Program Document has been developed in accordance with the requirements of NEI 12-06, Diverse and Flexible Coping Strategies (FLEX) Implementation Guide.

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

5. Order EA-12-051 Compliance Elements Summary APS has completed implementation of the new SFP level monitoring system which includes: diverse level sensors in the SFP, backup uninterruptible power supplies (UPS), and level indicators in the control room area and the Auxiliary Building. Modifications and training are complete and applicable procedures have been verified and are available for use in accordance with the site procedure control program.

6. Previous PVNGS Compliance Letter for NRC Orders EA-12-049 and EA 051 APS provided notification of full compliance with NRC Orders EA-12-049 and EA-12-051 for PVNGS Unit 1 (Reference 15) and Unit 3 (Reference 16).

References

1. 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, [Agencywide Documents Access And Management System (ADAMS) Accession No. ML13070A342]

2. NRC Order Number EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events, dated March 12, 2012, [ADAMS Accession Nos. ML13326A713 and ML13336A775]

3. APS Letter 102-06669, APS Overall Integrated Plan in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051), dated February 28, 2013,

[ADAMS Accession No. ML13070A077]

4. NRC Order Number EA-12-051, Order Modifying Licenses with Regard to Requirements for Reliable Spent Fuel Pool Instrumentation, dated March 12, 2012 [ADAMS Accession No. ML12054A682]

5. NRC Letter Palo Verde Nuclear Generating Station, Units 1, 2, and 3 - Interim Staff Evaluation Relating to Overall Integrated Plan in Response to Order EA-12-049 - Mitigation Strategies, dated November 25, 2013 [ADAMS Accession Nos. ML13326A713 and ML13308C153]

6. NRC Letter Palo Verde Nuclear Generating Station, Units 1, 2, and 3 - Report for the Audit Regarding Implementation of Mitigating Strategies and Reliable Spent Fuel Pool Instrumentation Related to Orders EA-12-049 and EA-12-051, dated September 8, 2014 [ADAMS Accession No. ML14239A181]

7. APS Letter 102-06758, APS First 6-Month Status Report on the PVNGS Overall Integrated Plan for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated August 28, 2013 [ADAMS Accession No. ML13246A007]

8. APS Letter 102-06840, APS Second 6-Month Status Report on the PVNGS Overall Integrated Plan for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated February 28, 2014 [ADAMS Accession No. ML14066A036]

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

9. APS Letter 102-06932, APS Third 6-Month Status Report on the PVNGS Overall Integrated Plan for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated August 28, 2014 [ADAMS Accession No. ML14246A211]

10. APS Letter 102-07005, APS Fourth 6-Month Status Report on the PVNGS Overall Integrated Plan for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated February 27, 2015 [ADAMS Accession No. ML15065A032]

11. APS Letter 102-07091, APS Fifth 6-Month Status Report on the PVNGS Overall Integrated Plan for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated August 14, 2015 [ADAMS Accession No. ML15232A028]

12. APS Letter 102-06885, APS Submittal of Phase 2 Staffing Assessment Report, dated June 11, 2014 [ADAMS Accession No. ML14167A397]

13. NRC Letter, Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Regarding Recommendations 2.1, 2.3, and 9.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-Ichi Accident, dated March 12, 2012 [ADAMS Accession No. ML12053A340]

14. NRC Letter, Response Regarding Licensee Phase 2 Staffing Submittals Associated With Near-Term Task Force Recommendation 9.3 Related To The Fukushima Dai-Ichi Nuclear Power Plant Accident, dated September 29, 2014,

[ADAMS Accession No. ML14262A296]

15. APS Letter 102-06985, Notification of Full Compliance with NRC Orders EA 049 and EA-12-051 for PVNGS Unit 1, dated January 9, 2015, [ADAMS Accession No. ML15012A444]

16. APS Letter 102-07048, Notification of Full Compliance with NRC Orders EA 049 and EA-12-051 for PVNGS Unit 3, dated May 26, 2015, [ADAMS Accession No. ML15149A020]

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT PVNGS Unit 2 Responses to Unit 2 Open and Pending Items

Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items APS provides the following responses for the Open and Pending Items identified in the NRC tracking system.

Item Description Summary Response ISE OI Separation of vehicles APS evaluated the seismic stability of 3.1.1.2.A to avoid seismic parked utility vehicles under the FLEX (Open) interactions canopy structure. The analysis was performed for the four categories of vehicles, namely, commercial trucks, debris removal vehicles, all-terrain vehicles (ATVs), and yard trucks.

The analysis concluded that the vehicles may slide by as much as 1 inch. Using a safety factor of 2, the design sliding displacement is 2 inches. The corresponding maximum horizontal displacement at the extreme top of the vehicles, as a result of rocking of these vehicles is calculated to be 4 inches. The calculated seismic movement is significantly less than the minimum prescribed separation distance of six feet.

Reference:

NM1000-A00057, Rev. 1, PVNGS FLEX Mods

- Yard Vehicles Seismic Stability Analyses:

Separation Requirements For Various Vehicles Under The Canopy Structure To Avoid Seismic Interaction ISE CI Analysis for ability of APS calculated the available net positive 3.2.2.A SFP makeup pump to suction head (NPSH) for the new FLEX (Open) deliver 200 gpm pump. The FLEX pump will take suction from either the Condensate Storage Tank (CST) or the Refueling Water Tank (RWT).

The pump discharge piping will be installed to provide make-up water to the Spent Fuel Pool (SFP) during beyond design basis external events. There will be fire hoses staged to connect either the CST or the RWT to the suction of the FLEX pump, depending upon availability and plant conditions.

The NPSH requirements were provided by the FLEX pump supplier and input into the computer model. The NPSH available for the Page 1

Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items Item Description Summary Response ISE CI required pump flow rate of 200 gallons per 3.2.2.A minute (gpm) is considerably higher than (Open) required and provides a substantial margin (Continued) above the NPSH requirements.

Reference:

NM1000-A00032, Rev. 1, Spent Fuel Pool Cooling FLEX Pump NPSH Availability ISE OI Station battery Performance testing was completed on 3.2.4.10.A extended discharge NCN-17 model batteries. The NCN-17 model (Open) rates battery was selected to represent all cell sizes due to the fact that it contains the least amount of electrolyte per unit volume for the NCN product line and it contains the largest number of plates per unit volume.

This was considered to be conservative and representative.

Two NCN-17 batteries were cycled in a controlled manner. Discharges were performed as follows:

• 8-hour discharge @ 150A

• 24-hour discharge @ 56A

• 72-hour discharge @ 21.2A This test data justifies that the discharge rates used for the PVNGS load shed battery analysis are reasonable.

References:

1. NEI Position Paper, Mitigating Strategies Resolution of Extended Battery Duty Cycles Generic Concern, ADAMS Accession No. ML13241A186

2. EN050B-A00024, Rev. 4, Installation, Operation And Maintenance Manual For Class 1E Batteries And Racks

3. NM1000-A00048, FLEX Project Study Report For The Battery Discharge Capacity During Extended Loss Of AC Power (ELAP)

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items Item Description Summary Response RAI-2-B Operator Actions and The FLEX Support Guideline (FSG) was (Open) consistency with CENTS based on the strategy developed from the analysis assumptions CENTS computer program, which used a 25 for RCP seal leakage gpm leak per Reactor Coolant Pump (RCP) to model the event. Operator training was developed based on the FSG and the analysis for responding to the Extended Loss of AC Power (ELAP) event. The Operations simulator ELAP scenario was programmed with the 25 gpm RCP seal leak/pump from an initiating seismic event and the time sensitive actions associated with Phase 1 and Phase 2 per the OIP were time validated to be feasible within the constraint times.

Item SE-8 below further describes the procedures.

References:

1. NM1000-A00002, Rev. 0, Palo Verde Units 1, 2 & 3 Beyond Design Bases Event-Extended Loss of AC Power

2. NLR14S050501 (Simulator Scenario)

Fukushima FLEX (CENTS Computer Model)

3. NLR14C050200 (Operator Training)

Fukushima FLEX Mods

4. 79IS-9ZZ07, Rev. 0, PVNGS Extended Loss of All Site AC Guideline Modes 1 - 4 RAI-14-B FLEX equipment should APS procurement specifications were issued (Open) be rated for the to purchase commercial FLEX portable environmental equipment, with the requirement of conditions in which it continuous operation at an ambient may be required to temperature of 130 degrees Fahrenheit (F).

operate. The limiting ambient temperature was selected based on the historical peak temperature recorded for Maricopa County, Arizona plus a design margin. All the FLEX equipment vendors have met this requirement.

References:

1. NM1000-A00015, Rev. 0, Electric Powered Positive Displacement Pumps For Palo Verde Diverse and Flexible Coping Page 3

Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items Item Description Summary Response RAI-14-B Strategies (FLEX)

(Open) 2. NM1000-A00016, Rev. 0, Diesel Powered (Continued) Centrifugal Pumps For Palo Verdes Diverse and Flexible Coping Strategies (FLEX)

3. NM1000-A00022, Rev. 1, 480 Volt Generator (APS FLEX)

RAI-27-B Analysis for FLEX pump Makeup flow requirements for the Steam (Open) sizing Generator (SG) and Reactor Coolant (RC)

Systems were developed per the ELAP analysis and used as an input for the FLEX pump sizing analysis. APS developed hydraulic models of the primary and alternate makeup flowpaths for both the SG and RC makeup strategies that will be used to implement FLEX for PVNGS.

The hydraulic models used a specified flow rate at a delivered system pressure and iterated the tank level until the NPSH requirements were met. The corresponding tank level, available NPSH, pump inlet pressure, and pump head were reported.

The pump speed was determined by examining the vendor data plots.

FLEX pumps were selected based on the analysis and vendor data.

Reference:

NM1000-A00020, Rev. 2, APS Palo Verde Nuclear Generating Station Detailed FLEX AFT FATHOM Models SE-4 (1)-(b) FLEX generator sizing Palo Verde plans to use two 800kW 480V (Open) FLEX generators for each unit to support Phase 2 operation during an ELAP event.

These generators are rated for 725kW at 104 degrees Fahrenheit ambient temperature. At a maximum ambient temperature of 130 degrees Fahrenheit the generators are conservatively derated to 500kW. APS has calculated the power factor (pf) of the total load demand and confirmed that the FLEX generators derated capacity exceeds the total load demand.

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items Item Description Summary Response SE-4 (1)-(b) The station is not using a 4160V power (Open) strategy as part of the FLEX coping (Continued) strategy (Phase 2). The 800kW 480V FLEX generators are adequate to supply the required power for the coping strategy per NEI 12-06 requirements.

Reference:

NM1000-A00065, Rev. 1, Palo Verde FLEX -

Load Flow & Motor Starting Calculation -

480V Train 'A' SE-6 Fuel Management The initial fuel management strategy is to (Open) Strategy for FLEX fill the Phase 2 diesel driven generators and Equipment and pumps from a selected emergency diesel Procedures generator day tank at each unit. Each day tank in the diesel building has a capacity of 1,100 gallons and a Technical Specification minimum volume of 550 gallons. The smaller diesel driven generators and pumps will be filled using portable fuel containers and fuel tote trailers. The fuel containers hold five gallons of fuel and are deployed with the specific equipment to the applicable locations. Three fuel tote trailers that hold 500 gallons (25 gpm transfer rate) each will be used to fill the portable FLEX equipment at each unit.

The fuel management strategy is governed by an approved PVNGS procedure.

Reference:

Procedure 14DP-0BD01, Rev. 0, PVNGS Portable FLEX Equipment Administrative Deployment Strategy SE-8 Verification and The FSGs have been developed and aligned (Open) Validation with industry guidelines. Site specific analysis and the FSG background documents prepared by the PWR Owners Group were used by APS during the development and verification of the FSGs.

The FSGs were reviewed and verified by the involved industry groups to ensure that the strategies are feasible and satisfy the Page 5

Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items Item Description Summary Response SE-8 guidance of NEI 12-06.

(Open)

(Continued) The FLEX equipment was tested under the procurement process (Factory Acceptance Testing) and the Design Change Process (Site Acceptance Testing) to verify equipment capability and performance PVNGS used the NEI FLEX Validation process to assure that required individual tasks, manual actions, and decisions for the FLEX strategies directed in the FSGs are feasible, may be executed as planned, and that there is reasonable margin to account for the unknown. Control Room FSG actions were validated in the simulator. Validations of field directed FSGs were performed to ensure that the FLEX equipment could be deployed and that portable equipment, including hoses, cables, fittings, etc., could be assembled as designed. These validations included transporting and staging pumps and generators, routing hoses and cables, simulating the alignment of makeup water sources and electrical distribution systems, and other actions in accordance with the FSGs.

An integrated validation was also completed to ensure adequate resources are available to accomplish the FLEX strategy as a whole.

PVNGS developed an integrated FLEX FSG schedule which included the required FSG actions and accounted for the associated resource (including staffing and equipment).

The integrated validation confirmed that PVNGS can successfully implement the FLEX strategies per the timeline using the minimum staffing documented in the Phase 2 Staffing Study.

Reference:

Condition Report Action Item (CRAI) 4580242 FLEX Validation Page 6

Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items Item Description Summary Response RAI-33-B Discuss the analysis

• Subsequent to the time this RAI was (Complete) (including methods, submitted NEI provided a position assumptions, and paper for Shutdown / Refueling results) to show that Modes, which has been accepted by core cooling with SG the NRC. This paper states that due not available can be to the large and diverse sets of maintained through individual equipment and system once through heat outage conditions which might exist removal from the RCS during a plant outage the strategies via coolant boil-off. are not fully analyzed. NEI 12-06 relies on the established concepts for outage planning and control including integrated management, level of activities, defense-in-depth, contingency planning, training and outage safety review. To effectively manage risk and maintain safety during outages, plants maintain contingencies to address the precautions and response actions for a loss of cooling but also direct the actions to be taken to respond to such an event. Consideration is given in the shutdown risk assessment process to:

• Maintaining FLEX equipment necessary to support shutdown risk processes and procedures readily available, and

• How FLEX equipment could be deployed or pre-deployed/pre-staged to support maintaining or restoring the key safety functions in the event of a loss of shutdown cooling.

RAI-34-B Provide the following

• Subsequent to the time this RAI was (Complete) items regarding the submitted NEI has provided a discussion of core position paper for Shutdown /

cooling with steam Refueling Modes, which has been generators not available accepted by the NRC. This paper in Phases 2 and 3: states that due to the large and diverse sets of individual equipment

b. The source of and system outage conditions which borated coolant once might exist during a plant outage the Page 7

Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items Item Description Summary Response the inventory of the strategies are not fully analyzed.

refueling water tank is NEI 12-06 relies on the established depleted (e.g., reactor concepts for outage planning and grade water, raw water control including integrated mixed with boric acid). management, level of activities, defense-in-depth, contingency planning, training and outage safety review. To effectively manage risk and maintain safety during outages, plants maintain contingencies to address the precautions and response actions for a loss of cooling but also direct the actions to be taken to respond to such an event.

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EA-12-049 EA-12-051 Maria L. Lacal Vice President, Nuclear Regulatory & Oversight Palo Verde Nuclear Generating Station P.O. Box 52034 Phoenix, AZ 85072 Mail Station 7605 Tel 623.393.6491 102-07157-MLL/TNW December 17, 2015 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk 11555 Rockville Pike Rockville, MD 20852

References:

1. NRC Order Number EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events, dated March 12, 2012

2. NRC Order Number EA-12-051, Order Modifying Licenses with Regard to Requirements for Reliable Spent Fuel Pool Instrumentation, dated March 12, 2012

Subject:

Palo Verde Nuclear Generating Station (PVNGS)

Units 1, 2, and 3 Docket Nos. STN 50-528, 50-529, and 50-530 Notification of Full Compliance with NRC Orders EA-12-049 and EA-12-051 for PVNGS Unit 2 On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued orders regarding mitigation strategies for beyond design bases external events and reliable spent fuel pool instrumentation (References 1 and 2).

Reference 1 required full implementation of mitigating strategies for beyond design basis external events no later than two refueling cycles after submittal of the Overall Integrated Plan (OIP) or December 31, 2016, whichever comes first. Reference 2 required full implementation of reliable spent fuel pool instrumentation no later than two refueling cycles after submittal of the OIP or December 31, 2016, whichever comes first. The orders also directed that achievement of full compliance be reported to the Commission.

This letter with the enclosure fulfills the requirement of the orders to report to the Commission that full compliance with the referenced orders has been achieved in PVNGS Unit 2. The enclosure provides a brief summary of the key elements associated with compliance to the orders. The attachment to the enclosure provides a high level summary response for each of the open and pending items being tracked by the NRC staff with regard to the orders. This letter also fulfills the requirement of the orders to report to the Commission that full compliance with the referenced orders has been achieved for PVNGS Units 1, 2, and 3. The Final Integrated Plan A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway

• Diablo Canyon

• Palo Verde

• Wolf Creek

102-07157-MLL/TNW ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Notification of Full Compliance with NRC Orders EA-12-049 and EA-12-051 for PVNGS Unit 2 Page 2 (FIP) reflecting the strategies for PVNGS Units 1, 2, and 3 is being submitted via separate letter.

No commitments are being made to the NRC by this letter.

Should you have any questions concerning the content of this letter, please contact Thomas Weber, Department Leader, Regulatory Affairs, at (623) 393-5764.

I declare under penalty of perjury that the foregoing is true and correct.

Executed on December 17, 2015 (Date)

Sincerely, Digitally signed by Lacal, Lacal, Maria Maria L(Z06149)

DN: cn=Lacal, Maria L(Z06149)

L(Z06149)

Date: 2015.12.17 10:22:13

-07'00' MLL/TNW/PJH/af

Enclosure:

PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051) cc: M. L. Dapas NRC Region IV Regional Administrator M. M. Watford NRC NRR Project Manager for PVNGS C. A. Peabody NRC Senior Resident Inspector for PVNGS J. P. Boska NRC NRR/JLD/JOMB Project Manager

ENCLOSURE PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

1. Introduction Arizona Public Service Company (APS) developed an Overall Integrated Plan (OIP)

(Reference 1) to provide diverse and flexible strategies (FLEX) in response to Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Reference 2). The information provided herein, as well as the implementation of the OIP, documents compliance with Order EA-012-049 for Palo Verde Nuclear Generating Station (PVNGS) Unit 2.

APS also developed an OIP (Reference 3) to address reliable spent fuel pool (SFP) instrumentation in response to Order EA-12-051 Order Modifying Licenses with Regard to Requirements for Reliable Spent Fuel Pool Instrumentation (Reference 4).

The information provided herein, as well as the implementation of the OIP, documents compliance with Order EA-012-051 for PVNGS Unit 2.

The full compliance with the referenced orders has been achieved for PVNGS Units 1, 2, and 3.

2. Open Item Resolution Issues from the NRC Interim Staff Evaluation (ISE) (Reference 5) and Audit Report (Reference 6) have been addressed by APS. The issues that were identified as open and pending in the NRC tracking system are listed below:

ISE Open Item (ISE OI) - ISE OI 3.1.1.2.A ISE Confirmatory Items (ISE CI) - ISE CI 3.2.2.A and 3.2.4.10.A Licensee Identified Open Items - PVNGS has no open or pending licensee identified open items.

Audit Questions/Audit Report Open/Pending Items - Items RAI-2-B, RAI-14-B, RAI-27-B, SE-4 (1)-(b), SE-6, SE-8, RAI-33-B and RAI-34-B A summary of the response to each of the issues is provided in the attachment to this enclosure. The open and pending items do not affect the compliance of Unit 2 to Order EA-012-049 or Order EA-012-051.

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

3. Milestone Schedule - Items Complete Unit 2 FLEX and SFPI Unit 2 FLEX Unit 2 SFPI Milestone Completion Date Completion Date Submit Overall Integrated Plan February 2013 February 2013 Submit 6 Month Updates:

Update 1 August 2013 August 2013 Update 2 February 2014 February 2014 Update 3 August 2014 August 2014 Update 4 February 2015 February 2015 Update 5 August 2015 August 2015 FLEX Strategy Evaluation September 2013 N/A Perform Staffing Analysis June 2014 N/A 1

Modifications:

Modifications Final Design Completion November 2014 July 2014 Unit 2 Final Modification Implementation October 2015 October 2015 Storage:1 Storage Design Engineering Completion March 2014 N/A Storage Implementation April 2015 N/A FLEX Equipment: 1 Procure On-Site Equipment April 2015 December 2014 1

Milestone actions were completed prior to Unit 2 Cycle 19 startup on November 14, 2015.

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

4. Order EA-12-049 Compliance Elements Summary The elements identified below for PVNGS Unit 2 as well as the FLEX OIP (Reference 1), the 6-Month Status Reports (References 7, 8, 9, 10, and 11) and additional docketed correspondence, demonstrate compliance with Order EA-12-049.

Strategies - Complete PVNGS Unit 2 strategies are in compliance with Order EA-12-049.

There are no strategy related Open Items, Confirmatory Items, or Audit Questions/Audit Report Open Items.

Modifications - Complete The modifications required to support the FLEX strategies for PVNGS Unit 2 have been fully implemented in accordance with the station processes.

Equipment - Procured and Maintenance & Testing - Complete The equipment required to implement the FLEX strategies for PVNGS Unit 2 has been procured, received at PVNGS, initially tested and performance verified as recommended in accordance with NEI 12-06, Diverse and Flexible Coping Strategies (FLEX) Implementation Guide and is available for use.

Maintenance and testing requirements are included in the PVNGS Preventative Maintenance Program such that equipment reliability is monitored and maintained.

Protected Storage - Complete The storage facility required to implement the FLEX strategies for PVNGS Unit 2 has been constructed and provides adequate protection from the applicable site hazards. The equipment required to implement the FLEX strategies for PVNGS Unit 2 is stored in its protected configuration.

The Units 1, 2, 3, and N+1 equipment have been moved into their final storage facility.

Procedures - Complete FLEX Support Guidelines (FSGs) for PVNGS Unit 2 have been developed and integrated with existing procedures. The FSGs and applicable procedures have been verified and are available for use in accordance with the site procedure control program.

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

Training - Complete Training for PVNGS Unit 2 has been completed in accordance with an accepted training process, as recommended in NEI 12-06, Diverse and Flexible Coping Strategies (FLEX) Implementation Guide.

Staffing - Complete The PVNGS Phase 2 staffing study for PVNGS (Reference 12) has been completed in accordance with 10 CFR 50.54(f) letter (Reference 13).

The NRC has reviewed the Phase 2 staffing study and concluded that it adequately addresses the response strategies needed to respond to a beyond design basis external event using Palo Verde procedures and guidelines. This is documented in NRC letter dated September 29, 2014 (Reference 14).

National Safer Response Centers - Complete APS has established a contract with Pooled Equipment Inventory Company (PEICo) and has joined the Strategic Alliance for FLEX Emergency Response (SAFER) Team Equipment Committee for off-site facility coordination. It has been confirmed that PEICo is ready to support PVNGS with Phase 3 FLEX equipment stored in the National SAFER Response Centers in accordance with the site specific SAFER Response Plan.

Validation - Complete APS has completed validation in accordance with industry developed guidance to assure required tasks, manual actions and decisions for FLEX strategies are feasible and may be executed within the constraints identified in the FLEX OIP for Order EA-12-049 (References 1 and 2).

FLEX Program Document - Established The APS PVNGS FLEX Program Document has been developed in accordance with the requirements of NEI 12-06, Diverse and Flexible Coping Strategies (FLEX) Implementation Guide.

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

5. Order EA-12-051 Compliance Elements Summary APS has completed implementation of the new SFP level monitoring system which includes: diverse level sensors in the SFP, backup uninterruptible power supplies (UPS), and level indicators in the control room area and the Auxiliary Building. Modifications and training are complete and applicable procedures have been verified and are available for use in accordance with the site procedure control program.

6. Previous PVNGS Compliance Letter for NRC Orders EA-12-049 and EA 051 APS provided notification of full compliance with NRC Orders EA-12-049 and EA-12-051 for PVNGS Unit 1 (Reference 15) and Unit 3 (Reference 16).

References

1. 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, [Agencywide Documents Access And Management System (ADAMS) Accession No. ML13070A342]

2. NRC Order Number EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events, dated March 12, 2012, [ADAMS Accession Nos. ML13326A713 and ML13336A775]

3. APS Letter 102-06669, APS Overall Integrated Plan in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051), dated February 28, 2013,

[ADAMS Accession No. ML13070A077]

4. NRC Order Number EA-12-051, Order Modifying Licenses with Regard to Requirements for Reliable Spent Fuel Pool Instrumentation, dated March 12, 2012 [ADAMS Accession No. ML12054A682]

5. NRC Letter Palo Verde Nuclear Generating Station, Units 1, 2, and 3 - Interim Staff Evaluation Relating to Overall Integrated Plan in Response to Order EA-12-049 - Mitigation Strategies, dated November 25, 2013 [ADAMS Accession Nos. ML13326A713 and ML13308C153]

6. NRC Letter Palo Verde Nuclear Generating Station, Units 1, 2, and 3 - Report for the Audit Regarding Implementation of Mitigating Strategies and Reliable Spent Fuel Pool Instrumentation Related to Orders EA-12-049 and EA-12-051, dated September 8, 2014 [ADAMS Accession No. ML14239A181]

7. APS Letter 102-06758, APS First 6-Month Status Report on the PVNGS Overall Integrated Plan for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated August 28, 2013 [ADAMS Accession No. ML13246A007]

8. APS Letter 102-06840, APS Second 6-Month Status Report on the PVNGS Overall Integrated Plan for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated February 28, 2014 [ADAMS Accession No. ML14066A036]

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

9. APS Letter 102-06932, APS Third 6-Month Status Report on the PVNGS Overall Integrated Plan for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated August 28, 2014 [ADAMS Accession No. ML14246A211]

10. APS Letter 102-07005, APS Fourth 6-Month Status Report on the PVNGS Overall Integrated Plan for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated February 27, 2015 [ADAMS Accession No. ML15065A032]

11. APS Letter 102-07091, APS Fifth 6-Month Status Report on the PVNGS Overall Integrated Plan for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated August 14, 2015 [ADAMS Accession No. ML15232A028]

12. APS Letter 102-06885, APS Submittal of Phase 2 Staffing Assessment Report, dated June 11, 2014 [ADAMS Accession No. ML14167A397]

13. NRC Letter, Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f) Regarding Recommendations 2.1, 2.3, and 9.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-Ichi Accident, dated March 12, 2012 [ADAMS Accession No. ML12053A340]

14. NRC Letter, Response Regarding Licensee Phase 2 Staffing Submittals Associated With Near-Term Task Force Recommendation 9.3 Related To The Fukushima Dai-Ichi Nuclear Power Plant Accident, dated September 29, 2014,

[ADAMS Accession No. ML14262A296]

15. APS Letter 102-06985, Notification of Full Compliance with NRC Orders EA 049 and EA-12-051 for PVNGS Unit 1, dated January 9, 2015, [ADAMS Accession No. ML15012A444]

16. APS Letter 102-07048, Notification of Full Compliance with NRC Orders EA 049 and EA-12-051 for PVNGS Unit 3, dated May 26, 2015, [ADAMS Accession No. ML15149A020]

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT PVNGS Unit 2 Responses to Unit 2 Open and Pending Items

Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items APS provides the following responses for the Open and Pending Items identified in the NRC tracking system.

Item Description Summary Response ISE OI Separation of vehicles APS evaluated the seismic stability of 3.1.1.2.A to avoid seismic parked utility vehicles under the FLEX (Open) interactions canopy structure. The analysis was performed for the four categories of vehicles, namely, commercial trucks, debris removal vehicles, all-terrain vehicles (ATVs), and yard trucks.

The analysis concluded that the vehicles may slide by as much as 1 inch. Using a safety factor of 2, the design sliding displacement is 2 inches. The corresponding maximum horizontal displacement at the extreme top of the vehicles, as a result of rocking of these vehicles is calculated to be 4 inches. The calculated seismic movement is significantly less than the minimum prescribed separation distance of six feet.

Reference:

NM1000-A00057, Rev. 1, PVNGS FLEX Mods

- Yard Vehicles Seismic Stability Analyses:

Separation Requirements For Various Vehicles Under The Canopy Structure To Avoid Seismic Interaction ISE CI Analysis for ability of APS calculated the available net positive 3.2.2.A SFP makeup pump to suction head (NPSH) for the new FLEX (Open) deliver 200 gpm pump. The FLEX pump will take suction from either the Condensate Storage Tank (CST) or the Refueling Water Tank (RWT).

The pump discharge piping will be installed to provide make-up water to the Spent Fuel Pool (SFP) during beyond design basis external events. There will be fire hoses staged to connect either the CST or the RWT to the suction of the FLEX pump, depending upon availability and plant conditions.

The NPSH requirements were provided by the FLEX pump supplier and input into the computer model. The NPSH available for the Page 1

Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items Item Description Summary Response ISE CI required pump flow rate of 200 gallons per 3.2.2.A minute (gpm) is considerably higher than (Open) required and provides a substantial margin (Continued) above the NPSH requirements.

Reference:

NM1000-A00032, Rev. 1, Spent Fuel Pool Cooling FLEX Pump NPSH Availability ISE OI Station battery Performance testing was completed on 3.2.4.10.A extended discharge NCN-17 model batteries. The NCN-17 model (Open) rates battery was selected to represent all cell sizes due to the fact that it contains the least amount of electrolyte per unit volume for the NCN product line and it contains the largest number of plates per unit volume.

This was considered to be conservative and representative.

Two NCN-17 batteries were cycled in a controlled manner. Discharges were performed as follows:

• 8-hour discharge @ 150A

• 24-hour discharge @ 56A

• 72-hour discharge @ 21.2A This test data justifies that the discharge rates used for the PVNGS load shed battery analysis are reasonable.

References:

1. NEI Position Paper, Mitigating Strategies Resolution of Extended Battery Duty Cycles Generic Concern, ADAMS Accession No. ML13241A186

2. EN050B-A00024, Rev. 4, Installation, Operation And Maintenance Manual For Class 1E Batteries And Racks

3. NM1000-A00048, FLEX Project Study Report For The Battery Discharge Capacity During Extended Loss Of AC Power (ELAP)

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items Item Description Summary Response RAI-2-B Operator Actions and The FLEX Support Guideline (FSG) was (Open) consistency with CENTS based on the strategy developed from the analysis assumptions CENTS computer program, which used a 25 for RCP seal leakage gpm leak per Reactor Coolant Pump (RCP) to model the event. Operator training was developed based on the FSG and the analysis for responding to the Extended Loss of AC Power (ELAP) event. The Operations simulator ELAP scenario was programmed with the 25 gpm RCP seal leak/pump from an initiating seismic event and the time sensitive actions associated with Phase 1 and Phase 2 per the OIP were time validated to be feasible within the constraint times.

Item SE-8 below further describes the procedures.

References:

1. NM1000-A00002, Rev. 0, Palo Verde Units 1, 2 & 3 Beyond Design Bases Event-Extended Loss of AC Power

2. NLR14S050501 (Simulator Scenario)

Fukushima FLEX (CENTS Computer Model)

3. NLR14C050200 (Operator Training)

Fukushima FLEX Mods

4. 79IS-9ZZ07, Rev. 0, PVNGS Extended Loss of All Site AC Guideline Modes 1 - 4 RAI-14-B FLEX equipment should APS procurement specifications were issued (Open) be rated for the to purchase commercial FLEX portable environmental equipment, with the requirement of conditions in which it continuous operation at an ambient may be required to temperature of 130 degrees Fahrenheit (F).

operate. The limiting ambient temperature was selected based on the historical peak temperature recorded for Maricopa County, Arizona plus a design margin. All the FLEX equipment vendors have met this requirement.

References:

1. NM1000-A00015, Rev. 0, Electric Powered Positive Displacement Pumps For Palo Verde Diverse and Flexible Coping Page 3

Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items Item Description Summary Response RAI-14-B Strategies (FLEX)

(Open) 2. NM1000-A00016, Rev. 0, Diesel Powered (Continued) Centrifugal Pumps For Palo Verdes Diverse and Flexible Coping Strategies (FLEX)

3. NM1000-A00022, Rev. 1, 480 Volt Generator (APS FLEX)

RAI-27-B Analysis for FLEX pump Makeup flow requirements for the Steam (Open) sizing Generator (SG) and Reactor Coolant (RC)

Systems were developed per the ELAP analysis and used as an input for the FLEX pump sizing analysis. APS developed hydraulic models of the primary and alternate makeup flowpaths for both the SG and RC makeup strategies that will be used to implement FLEX for PVNGS.

The hydraulic models used a specified flow rate at a delivered system pressure and iterated the tank level until the NPSH requirements were met. The corresponding tank level, available NPSH, pump inlet pressure, and pump head were reported.

The pump speed was determined by examining the vendor data plots.

FLEX pumps were selected based on the analysis and vendor data.

Reference:

NM1000-A00020, Rev. 2, APS Palo Verde Nuclear Generating Station Detailed FLEX AFT FATHOM Models SE-4 (1)-(b) FLEX generator sizing Palo Verde plans to use two 800kW 480V (Open) FLEX generators for each unit to support Phase 2 operation during an ELAP event.

These generators are rated for 725kW at 104 degrees Fahrenheit ambient temperature. At a maximum ambient temperature of 130 degrees Fahrenheit the generators are conservatively derated to 500kW. APS has calculated the power factor (pf) of the total load demand and confirmed that the FLEX generators derated capacity exceeds the total load demand.

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Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items Item Description Summary Response SE-4 (1)-(b) The station is not using a 4160V power (Open) strategy as part of the FLEX coping (Continued) strategy (Phase 2). The 800kW 480V FLEX generators are adequate to supply the required power for the coping strategy per NEI 12-06 requirements.

Reference:

NM1000-A00065, Rev. 1, Palo Verde FLEX -

Load Flow & Motor Starting Calculation -

480V Train 'A' SE-6 Fuel Management The initial fuel management strategy is to (Open) Strategy for FLEX fill the Phase 2 diesel driven generators and Equipment and pumps from a selected emergency diesel Procedures generator day tank at each unit. Each day tank in the diesel building has a capacity of 1,100 gallons and a Technical Specification minimum volume of 550 gallons. The smaller diesel driven generators and pumps will be filled using portable fuel containers and fuel tote trailers. The fuel containers hold five gallons of fuel and are deployed with the specific equipment to the applicable locations. Three fuel tote trailers that hold 500 gallons (25 gpm transfer rate) each will be used to fill the portable FLEX equipment at each unit.

The fuel management strategy is governed by an approved PVNGS procedure.

Reference:

Procedure 14DP-0BD01, Rev. 0, PVNGS Portable FLEX Equipment Administrative Deployment Strategy SE-8 Verification and The FSGs have been developed and aligned (Open) Validation with industry guidelines. Site specific analysis and the FSG background documents prepared by the PWR Owners Group were used by APS during the development and verification of the FSGs.

The FSGs were reviewed and verified by the involved industry groups to ensure that the strategies are feasible and satisfy the Page 5

Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items Item Description Summary Response SE-8 guidance of NEI 12-06.

(Open)

(Continued) The FLEX equipment was tested under the procurement process (Factory Acceptance Testing) and the Design Change Process (Site Acceptance Testing) to verify equipment capability and performance PVNGS used the NEI FLEX Validation process to assure that required individual tasks, manual actions, and decisions for the FLEX strategies directed in the FSGs are feasible, may be executed as planned, and that there is reasonable margin to account for the unknown. Control Room FSG actions were validated in the simulator. Validations of field directed FSGs were performed to ensure that the FLEX equipment could be deployed and that portable equipment, including hoses, cables, fittings, etc., could be assembled as designed. These validations included transporting and staging pumps and generators, routing hoses and cables, simulating the alignment of makeup water sources and electrical distribution systems, and other actions in accordance with the FSGs.

An integrated validation was also completed to ensure adequate resources are available to accomplish the FLEX strategy as a whole.

PVNGS developed an integrated FLEX FSG schedule which included the required FSG actions and accounted for the associated resource (including staffing and equipment).

The integrated validation confirmed that PVNGS can successfully implement the FLEX strategies per the timeline using the minimum staffing documented in the Phase 2 Staffing Study.

Reference:

Condition Report Action Item (CRAI) 4580242 FLEX Validation Page 6

Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items Item Description Summary Response RAI-33-B Discuss the analysis

• Subsequent to the time this RAI was (Complete) (including methods, submitted NEI provided a position assumptions, and paper for Shutdown / Refueling results) to show that Modes, which has been accepted by core cooling with SG the NRC. This paper states that due not available can be to the large and diverse sets of maintained through individual equipment and system once through heat outage conditions which might exist removal from the RCS during a plant outage the strategies via coolant boil-off. are not fully analyzed. NEI 12-06 relies on the established concepts for outage planning and control including integrated management, level of activities, defense-in-depth, contingency planning, training and outage safety review. To effectively manage risk and maintain safety during outages, plants maintain contingencies to address the precautions and response actions for a loss of cooling but also direct the actions to be taken to respond to such an event. Consideration is given in the shutdown risk assessment process to:

• Maintaining FLEX equipment necessary to support shutdown risk processes and procedures readily available, and

• How FLEX equipment could be deployed or pre-deployed/pre-staged to support maintaining or restoring the key safety functions in the event of a loss of shutdown cooling.

RAI-34-B Provide the following

• Subsequent to the time this RAI was (Complete) items regarding the submitted NEI has provided a discussion of core position paper for Shutdown /

cooling with steam Refueling Modes, which has been generators not available accepted by the NRC. This paper in Phases 2 and 3: states that due to the large and diverse sets of individual equipment

b. The source of and system outage conditions which borated coolant once might exist during a plant outage the Page 7

Enclosure PVNGS Unit 2 Summary of Compliance with NRC Orders Regarding Mitigation Strategies for Beyond-Design-Basis External Events (EA-12-049) and Reliable Spent Fuel Pool Instrumentation (EA-12-051)

ATTACHMENT - Responses to Unit 2 Open and Pending Items Item Description Summary Response the inventory of the strategies are not fully analyzed.

refueling water tank is NEI 12-06 relies on the established depleted (e.g., reactor concepts for outage planning and grade water, raw water control including integrated mixed with boric acid). management, level of activities, defense-in-depth, contingency planning, training and outage safety review. To effectively manage risk and maintain safety during outages, plants maintain contingencies to address the precautions and response actions for a loss of cooling but also direct the actions to be taken to respond to such an event.

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