RS-14-009, Second Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond Design-Basis External Events (Order No. EA-12-049)

Second Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond Design-Basis External Events (Order No. EA-12-049)

ML14059A429
Person / Time
Site:	Clinton
Issue date:	02/28/2014
From:	Kaegi G T Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
EA-12-049, RS-14-009
Download: ML14059A429 (37)

Text

1 p Exelon Generation Order No. EA-12-049 RS-14-009 February 28, 2014 u.s. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Clinton Power Station, Unit 1 Facility Operating License No. I\IPF-62 NRC Docket No. 50-461

Subject:

Second Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Design-Basis External Events (Order Number EA-12-049)

References:

1. NRC Order Number EA-12-049, "Issuance of Order to Modify Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events," dated March 12,2012 2. NRC Interim Staff Guidance ... ILD-ISG-2012-01, "Compliance with Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events," Revision 0, dated August 29,2012 3. NEI 12-06, "Diverse and Flexible Coping Strategies (FLEX) Implementation Guide," Revision 0, dated August 2012 4. Exelon Generation Company, LLC's Initial Status Report in Response to March 12,2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for 8eyond-Design-Basis External Events (Order Number EA-12-049), dated October 25, 2012 5. Exelon Generation Company, LLC 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 (RS-13-019)

6. Exelon Generation Company, LLC First Six-Month Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for IVlitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated August 28, 2013 (RS-13-117)

7. NRC letter to Exelon Generation Company, LLC, Clinton Power Station, Unit 1 -Interim Staff Evaluation Relating to Overall Integrated Plan in Response to Order EA-12-049 (Mitigation Strategies) (TAC Nos. MF0901), dated December 17,2013 U.S. Nuclear Regulatory Commission Integrated Plan Report to EA-12-049 February 28, 2014 Page 2 On March 12, 2012, the Nuclear Regulatory Commission

("NRC" or "Commission")

issued an order (Reference

1) to Exelon Generation Company, LLC (EGC). Reference 1 was immediately effective and directs EGC to develop, implement, and maintain guidance and strategies to maintain or restore core cooling, containment, and spent fuel pool cooling capabilities in the event of a beyond-design-basis external event. Specific requirements are outlined in Attachment 2 of Reference 1 . Reference 1 required submission of an initial status report 60 days following issuance of the final interim staff guidance (Reference

2) and an overall integrated plan pursuant to Section IV, Condition C. Reference 2 endorses industry guidance document NE112-06, Revision 0 (Reference

3) with clarifications and exceptions identified in Reference

2. Reference 4 provided the EGC initial status report regarding mitigation strategies.

Reference 5 provided the Clinton Power Station, Unit 1 overall integrated plan. Reference 1 requires submission of a status report at six-month intervals following submittal of the overall integrated plan. Reference 3 provides direction regarding the content of the status reports. Reference 6 provides the first six-month status report pursuant to Section IV, Condition C.2, of Reference 1 for Clinton Power Station. The purpose of this letter is to provide the second six-month status report pursuant to Section IV, Condition C.2, of Reference 1, that delineates progress made in implementing the requirements of Reference

1. The enclosed report provides an update of milestone accomplishments since the last status report, including any changes to the compliance method, schedule, or need for relief and the basis, if any. The enclosed report also addresses the !\IRC Interim Staff Evaluation Open and Confirmatory Items contained in Reference

7. This letter contains no new regulatory commitments.

If you have any questions regarding this report, please contact David P. Helker at 610-765-5525.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 28 th day of February 2014. Respectfully submitted, Glen T. Kaegi Director -Licensing

& Regulatory Affairs Exelon Generation Company, LLC

Enclosure:

1. Clinton Power Station, Unit 1 Second Six-Month Status Report for the Implementation of Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events U.S. Nuclear Regulatory Commission Integrated Plan Report to February 28, 2014 Page 3 cc: Director, Office of Nuclear Reactor Regulation NRC Regional Administrator

-Region III NRC Senior Resident Inspector

-Clinton Power Station, Unit 1 NRC Project Manager, NRR -Clinton Power Station, Unit 1 Ms. Jessica A. Kratchman, NRR/,JLD/PMB, NRC Mr. Jack R. Davis, NRRlDPRlMSD, NRC Mr. Eric E. Bowman, NRR/DPRIMSD, NRC Mr. Jeremy S. Bowen, NRR/DPR/MSD/MSPB, NRC Mr. Robert L. Dennig, NRR/DSS/SCVB, NRC Mr. John Boska, NRR/DPR/MSDIMSPB, NRC Illinois Emergency Management Agency -Division of Nuclear Safety Enclosure Clinton Power Station, Unit 1 Second Six-Month Status Report for the Implementation of Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Design-Basis External Events (33 pages)

Enclosure Clinton Power Station's Second Six Month Status Report for the Implementation of Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Basis External Events (33 pages) 1 Introduction Clinton Power Station developed an Overall Integrated Plan (Reference i), documenting the diverse and flexible strategies (FLEX), in response to Reference

2. This attachment provides an update of milestone accomplishments since submittal of the Overall Integrated Plan, including any changes to the compliance method, schedule, or need for relief/relaxation and the basis, if any. 2 Milestone Accomplishments None 3 Milestone Schedule Status The following provides an update to Attachment 2 of the Overall Integrated Plan. It provides the activity status of each item, and whether the expected completion date has changed. The dates are planning dates subject to change as design and implementation details are developed.

Original Target Activity Status Completion Date {Include date changes in this column} Submit 60 Day Status Report Complete Submit Overall Integrated Complete Implementation Plan Contract with RRC Complete , Aug 2013 Submit 6 month update Complete Feb 2014 Submit 6 month update Complete with this submittal Aug 2014 Submit 6 month update Not Started Feb 2015 Submit 6 month update Not Started lViodification Development Mar 2014

• Phase 2 modifications Started Dec 2014 Regional Response Center Started Operational Procedure development Feb 2015 Strategy procedures Started Page 1 of 33 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 Feb 2015 Validate Procedures (NEI12-06, Sect. Not Started 11.4.3) May 2015 Maintenance procedures I\lot Started Feb 2015 Staffing analysis Not Started Modification Implementation May 2015

• Phase 2 modifications Started May 2015 Storage plan and construction Not Started May 2015 FLEX equipment acquisition Started May 2015 Training completion

!\lot Started May 2015 Unit 1 Implementation date Not Started 4 Changes to Compliance Method Note: In the discussions below, italics are used to highlight the significant changes. Change 1 General Integrated Plan Elements BWR -Provide a sequence of events and identify any time constraint required for success including the technical basis for the time constraint. -Item 2 Containment Analysis.

Reason for Change: This discussion is updated to include results from MAAP analysis of the containment strategy using a higher suppression pool temperature as the trigger for suppression pool makeup (SPMU) from the upper containment pool. The increase in the trigger temperature provides additional time to supply the SPMU valves with AC power from a FLEX generator.

The change has a negligible effect on the overall containment response.

Change: As part of the implementation plan of NEI12-06, the BWROG performed evaluations of generic Boiling Water Reactor (BWR) response to Extended Loss of AC Power (ELAP) events to demonstrate the efficacy of the FLEX strategies.

Reference 3 provides the results of those evaluations for several representative BWR plant designs. Several Clinton Modular Accident Analysis Program (MAAP) [Reference 41 cases were run to analyze methods of containment heat removal, including containment venting, suppression pool feed and bleed, and suppression pool cooling using a FLEX strategy.

The MAAP cases indicate an alternate suppression pool cooling method provides the fewest operational challenges while providing margin to the primary containment design pressure limit. UHS temperature was designated at 91.4°F in the alternate suppression pool cooling cases. The following time constraints were used as MAAP input parameters, or were identified in the FLEX suppression pool cooling MAAP Case 17 results: a. RPV pressure is reduced to a pressure band of 150-250 psig at a rate of 50°F/hr starting at t o+ 1 hr. Page 2 of33 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 b. Suppression Pool Heat Capacity Temperature Limit (HCTl) is reached in t o+ 3.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />. Emergency Depressurization is not required since RCIC is being used for level control during SBO conditions per CPS 4402.01, EOP-6 PRIMARY CONTAINMENT CONTROL [Reference 5]. c. Suppression Pool Makeup (SPMU) from the upper containment pool is designated to occur at 190°F suppression pool temperature to extend the time required to establish the suppression pool cooling lineup, and to allow time for a FLEX generator to provide AC power to the SPMU valves in the containment.

Electrical power to the SPMU valves is available at t o+ 5.5 hrs. d. The suppression pool cooling lineup is designated to occur at t o+ 8 hrs to provide the maximum time for establishing a suppression pool cooling lineup using a FLEX strategy, while maintaining acceptable containment parameter values. The service water tube side flow from the FLEX pump was designated at 2000 gpm, and the shell side suppression pool flow was designated at 1500 gpm. These flow rates are within the capacities of the pumps supplying suppression pool and cooling water flow. The peak suppression pool temperature in this case is 209.41 of at to + 19.02 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. This value is well below the acceptable suction temperature established in the BWROG feasibility study for RCIC operation in a prolonged station blackout [Reference 6]. Peak containment pressure is 24.9 psia at to + 45.9 hours1.041667e-4 days <br />0.0025 hours <br />1.488095e-5 weeks <br />3.4245e-6 months <br />, compared to containment design pressure of 29.7 psia. e. Suppression pool makeup from an external source was designated to maintain level between the values of 23 ft. and 23 ft 9 in. The first injection of makeup occurs at to + 8.02 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. Change 2 Maintain Core Cooling -BWR Portable Equipment Phase 2 Reason for Change: This discussion is updated to 1) describe a change in the method used to supply the ADS valves with motive air after the backup air bottles are exhausted, 2) change the RPV pressure assumed for makeup from a FLEX pump from 50 psig to 60 psig, and 3) include a discussion concerning injection of raw water into the RPV. Change: During Phase 2, high pressure RPV makeup is provided from RCIC and RPV pressure control is provided from RCIC and the SRVs. A pre-staged 480 VAC generator will be lined up to the Division 1 AC distribution system to repower the Division 1 battery charger and enable the continued use of RClC, SRVs, and vital instrumentation.

An installed Diesel Generator Starting Air Compressor will be aligned to make up to the ADS backup air bottles, if required (Figure 5). Alternatively, a separate generator can be lined up to the swing battery charger to maintain the Division 1 DC bus energized

[Reference 7]. Once the suppression pool lineup is completed, RCIC suction will be shifted to the RHR heat exchanger shell outlet using installed RHR steam condensing mode piping (Figure 1). This action limits the RCiC system exposure to elevated suppression pool temperature to the first eight hours of the event. The maximum water temperature the RCIC pump is exposed to is 200. l"F according to the MAAP analysis.

Once the RCIC suction is shifted the RCiC suction water temperature is 138°F. To accomplish low pressure RPV makeup when RCIC is no longer available, the suppression pool cooling return path can be directed to the RPV using installed RHR system lPCI valve. Additionally, external water connections will be provided to a location that supports connection to the modified low Pressure Core Spray (lPCS) [Reference 8] and the Residual Heat Removal (RHR) C [Reference 9] injection header. A pre-staged section of fire hose allows the final connection from the external water supply to the injection header (see Figure 3). The injection valves for these two systems are located outside the Page 3 of 33 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 primary containment and can be operated manually with the handwheel or electrically via the FLEX generator.

Raw water flow to the RPV from LPCS or RHR-C is directed inside the core shroud. The potential for blockage of fuel bundle flow orifices is minimized using these systems. Additionally, the procedure for low pressure RPV and suppression pool makeup will provide a prioritized list of cleaner water sources using equipment that may be available after the event has occurred [Confirmatory Item 3.2.1.4.B}.

RPV pressure will need to be further reduced to approximately 60 psig with SRVs to achieve the flow rate necessary from the external water connection.

The supply to the external water connections is described in the Safety Function Support Phase 2 section. The Suppression Pool Cleanup and Transfer Pump and the external connection will each be capable of meeting the decay heat boil-off rate, plus the assumed system leakage from reactor recirculation pump seals. Core cooling can be maintained indefinitely with RCIC first, then the suppression pool cooling pump with SRVs controlling RPV pressure, and finally the pre-staged diesel driven pump with SRVs controlling RPV pressure [Reference 4]. Change 3 Maintain Core Cooling -BWR Portable Equipment Phase 2 -Identify Modifications Reason for Change: Clinton identified a simpler method (Figure 5) of supplying air to ADS valves when the Backup Air Bottles are exhausted.

Change: Identify modifications List modifications Change 4

• Two diverse external connections for a portable diesel powered pump to supply low pressure RPV makeup water in the plant.

• The LPCS and RHR-C injection header flush line will be modified with a connection point for the low pressure water supply.

• Piping will be installed to support the connection of the external connections to the LPCS and RHR-C injection headers.

• A tee will be installed in the ADS Backup Air Bottles charging line in the Division 1 Diesel Generator room to allow an installed Division 1 or Division 2 Diesel Generator Starting Air Compressor to supply motive air to ADS valves when the backup air bottles are exhausted.

• The electrical support and cooling/makeup water support modifications needed for the core cooling function are discussed in the Safety Function Support section. Maintain Core Cooling -BWR Portable Equipment Phase 2 -Storage / Protection of Equipment Reason for Change: Provide more detail concerning storage and protection of equipment.

Change: A table addressing the guidance in NE112-06 Sections 6 through 9 is included in Attachment

2. Page 4 of33 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 Storage / Protection of Equipment:

Describe storage / protection plan or schedule to determine storage requirements Seismic List how equipment is protected or schedule to protect Structures to provide protection of FLEX equipment will be constructed to meet the requirements of NEI 12-06 Section 11. Schedule to construct permanent buildings is contained in Section 3 of this document, and will satisfy the site compliance date. Temporary locations will be used until building construction completion.

Procedures and programs will be developed to address storage structure requirements, haul path requirements, and FLEX equipment requirements relative to the external hazards applicable to Clinton Power Station. With respect to a seismic event, the storage plan does not require clearing debris from a haul path since the FLEX pumps and generators are pre-staged near their connection points. FLEX cables, hoses and permanent plant equipment used in the mitigating strategies are all designed to be protected from the seismic event, or will be analyzed or upgraded to ensure their survival.

Flooding List how equipment is protected or schedule to protect Note: if stored below current Structures to provide protection of FLEX equipment will be constructed to flood level, then ensure meet the requirements of NE112-06 Section 11. Schedule to construct procedures exist to move permanent buildings is contained in Section 3 of this document, and will equipment prior to exceeding satisfy the site compliance date. Temporary locations will be used until flood level building construction completion.

Procedures and programs will be developed to address storage structure requirements, haul path requirements, and FLEX equipment requirements relative to the external hazards applicable to Clinton Power Station. With respect to flooding, the storage building housing the FLEX pumps will not be protected up to the PMF elevation.

Sufficient time will be available to relocate the FLEX pump to a higher elevation in advance of the rising lake level. The haul path for relocating the FLEX pump will not be affected by the flood. Since the FLEX pump connection will be submerged, hoses with sufficient capacity to provide the required flow rate will be deployed with the FLEX pump. The hoses will connect to the Regional Response Center connection point to supply the required flow for the mitigating strategies.

Station procedures governing high lake level will contain guidance for maintaining fLAP response capability during a flooding event. Severe Storms with List how equipment is protected or schedule to protect High Winds Structures to provide protection of FLEX equipment will be constructed to meet the requirements of NE112-06 Section 11. Schedule to construct permanent buildings is contained in Section 3 of this document, and will satisfy the site compliance date. Temporary locations will be used until building construction completion.

Procedures and programs will be Page 5 of 33 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 developed to address storage structure requirements, haul path requirements, and FLEX equipment requirements relative to the external hazards applicable to Clinton Power Station. Snow, Ice, and List how equipment is protected or schedule to protect Extreme Cold Structures to provide protection of FLEX equipment will be constructed to meet the requirements of NE112-06 Section 11. Schedule to construct permanent buildings is contained in Section 3 of this document, and will satisfy the site compliance date. Temporary locations will be used until building construction completion.

Procedures and programs will be developed to address storage structure requirements, haul path requirements, and FLEX equipment requirements relative to the external hazards applicable to Clinton Power Station. With respect to snow, ice, and extreme cold, the storage plan does not require clearing snow or ice from a haul path since the FLEX pumps and generators are prestaged near their connection points. All operator actions during the first hours of the event are performed indoors; either inside the plant or inside the FLEX storage building at the Screen House. High Temperatures List how equipment is protected or schedule to protect Structures to provide protection of FLEX equipment will be constructed to meet the requirements of I\IEI 12-06 Section 11. Schedule to construct permanent buildings is contained in Section 3 of this document, and will satisfy the site compliance date. Temporary locations wifl be used until building construction completion.

Procedures and programs will be developed to address storage structure requirements, haul path requirements, and FLEX equipment requirements relative to the external hazards applicable to Clinton Power Station. Change 5 Safety Functions Support -BWR Portable Equipment Phase 2 Reason for Change: This discussion is updated to correct the electrical deployment time line and tie it to energizing the 480 VAC MCC that supplies the SPMU valves. Change: Electrical Support Key portions of the Division 1, Division 2, and non-divisional 480 VAC distribution system will be able to be re-energized from a pre-staged primary or alternate FLEX generator.

Either generator independently will enable maintaining DC power for RClC, SRV controls and vital instrumentation, and provide AC power for hydrogen igniters, SPMU valves and Suppression Pool Cleanup and Transfer pumps (Figure 4). The primary and alternate FLEX generator and cabling will be permanently housed in the Unit 2 side of the Control and Diesel Generator buildings, so deployment will not be impeded by a beyond design basis external event (BDBEE). Where necessary to meet the requirements of the time line, some connecting Page 6 of 33 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28,2014 cabling will be pre-routed from the vicinity of the primary and alternate FLEX generators to the vicinity of the required 480 VAC unit substations which will have connection points for an external source of power. Where supported by the timeline and staffing, some cabling will be manually deployed at the time of the event. Once the event is identified as an ELAPjLLlHS, operations personnel will line up and start the primary or alternate FLEX generator and perform a lineup that enables key 480 VAC components, including the SPMU valves and Division 1 battery charger, to be re-energized by to+S.S hrs. Change 6 Safety Functions Support -B WR Portable Equipment Phase 2 -Deployment Conceptual Design Reason for Change: This discussion is updated to describe the deployment methods for electrical and mechanical connections.

Change: Deployment Conceptual Design (Figure 7 contains a deployment conceptual sketch) Strategy Modifications Protection of connections Identify Strategy including Identify modifications Identify how the connection is how the equipment will be protected deployed to the point of use. Electrical Support (Figure 4) The primary and alternate

• A permanently staged primary Phase 2 FLEX generator will be and alternate 480 VAC The FLEX electrical connections permanently staged and generator able to supply will be completed inside the do not require necessary portions of the 480 Diesel Generator Building, which deployment.

VAC distribution system to repower the Division 1 battery is protected from all external Pre-staged cabling will be charger or the swing battery hazards. deployed from the FLEX charger and other needed AC Phase 3 generator to the Unit loads. Substations that supply

• Two electrical connection points The electrical connection for an the components needed able to supply necessary external generator from the to meet the FLEX timeline.

portions of the 480 VAC Regional Response Center (RRCj distribution system from an to the required portions of the external source to repower the installed 480 VAC system will be Division 1 battery charger or deployed, if needed, from within the swing battery charger to the Diesel Generator Building supply DC MCC lA, and other through an engineered opening in needed AC loads. external wall to the outside "A2"

• Pre-routed and pre-staged staging area . cabling with cam-lock An alternate connection point connectors and cabling will be located inside Page 7 of 33 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 the protected Control Building.

Cooling/Makeup Water Support (Figure 3) The diesel driven pumps Two external water connections.

will be housed in a storage structure that meets I\IE112-06 Rev.O storage requirements.

A heavy duty truck capable of clearing debris will be stored in the same location.

The proposed means of Connection to the Unit 2 SX routing the water from supply piping from the UHS FLEX the UHS to the plant is via pump. the unused seismically robust Unit 2 SX piping. Change 7 Attachment lA -Sequence of Events Timeline Reason for Change: Phase 2 The FLEX mechanical connections will be completed inside the Control Building, which is protected from all external hazards. Phase 3 The mechanical connection for an external pump from the Regional Response Center (RRC), if needed, to the SX system will be inside a robust building on the Unit 2 side of the Screen House adjacent to the tAl" staging area. An alternate connection will be deployed from within the Diesel Generator Building through an engineered opening in the external wall to the outside ttA2" staging area using a hose pre-staged for this purpose inside the protected Diesel Generator Building.

1. The timeline for energizing key components from a FLEX generator was set at 1:0 + 5 hrs. This was overly restrictive since the DC coping analysis [Reference 10] extended Division 1 battery life to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. The coping analysis itself was conservative in that 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> includes consideration of a battery aging factor. Eliminating the battery aging factor extends the coping time further to 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. 2. An additional MAAP run (Case 17) was performed to analyze the effect on containment response of moving the SPMU trigger from 180°F to 190°F suppression pool temperature.

190°F corresponds to approximately

5.5 hour5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />s

on the timeline.

3. Preliminary calculation of diesel generator fuel consumption rate and tank capacity should provide a minimum of 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> of run time. Assuming the generator is started at 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, refueling is required at To+14 hours. Page 8 of 33 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28,2014 Change: The time to open the SPMU valves occurs on the timeline at to + 5.5 hrs. This is the time at which a FLEX generator needs to be aligned to energize key 480 VAC busses. FLEX fuel oil supply shifted from To+8 hrs. to To+14 hrs. since the generator and pump fuel capacities will provide at least this much time. Time Remarks I Applicability Action Elapsed Action Constraint item Time (if blank then no change from alP YIN submittal) 0 Event starts, Scram, Recirc Pumps Trip NA Level 2 1 RCiC has started and begins to inject NA +30 sec 2 10 min Control level and pressure per procedures Y 3 29 min Bypass RCiC leak detection isolation logic Y Defeat Low RCiC Steam Supply Pressure 4 1 hr Isolation per CPS 4410.01C001, Defeating N RCiC Interlocks 5 1 hr Initiate CPS 4200.01C003, Monitoring CNMT N Temperatures During A SBO 6 1 hr Complete CPS 4200.01C002, DC Load Shedding During A SBO y 7 1 hr Initiate Beyond Design Basis FLEX Strategies Y Begin RPV depressurization to 150 psig with 8 1 hr SRVs at 50°F/hr. Control RPV pressure Y between 150 and 250 psig. 9 1 hr Commence Lining Up FLEX generator N 10 2 hr Commence UHS Pump Deployment N 11 2 hr Place ADS Backup Air Bottles in service per CPS 3101.01, Main Steam (MS, IS & ADS). y 12 5.5 hr Energize MCC 1A3 N Time derived from allowing suppression pool temperature to reach 13 5.5 hr Open the SPMU valves Y 190°F before dumping the upper containment pool. Containment response analyzed in Rev 3 of the MAAP analysis.

14 5.5 hr Energize MCC 1A1 N Page 9 of 33 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 15 5.5 hr Startup Div 1 Battery Charger and supply DC y MCC1A 16 5.5 hr Energize Hydrogen Igniter Distribution Panel (MCC 1A1) N 17 5.5 hr Energize DG MCC 1A and Standby Lighting N Cabinet 1LL70EA 18 6 hr Open RCIC room doors Y 19 8 hr Place FLEX suppression pool cooling strategy y in service 20 8 hr Makeup to Suppression Pool as needed Y Time changed from 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> to 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> in the August 2013 update. 21 8 hr FLEX pump available for RPV makeup N Confirmatory Item 3.2.1.3.A 22 12 hr Initiate supplemental MCR ventilation per N CPS 4200.01C001, MCR Cooling During A SBO 23 12 hr Commence Spent Fuel Pool makeup (>86 y gpm) as needed 24 12 hr Establish Fuel Bldg steam vent path N Preliminary calculation of fuel consumption rate and tank capacity 25 14 hr Connect Div 1 Day Tank 120 VAC portable y should provide a minimum of 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> pump of run time. Assuming the generator is started at 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, refueling is required at To+14 hours. 26 24 hr Commence recharging the ADS backup air bottles with a FLEX air compressor y 27 24 hr First piece of RRC equipment arrives at the N staging area 28 30 hr Establish RCiC Pump Room compensatory y action (portable fan) Continue to maintain critical functions of core cooling (via RClC), containment (via 29 24-72 hr alternate suppression pool cooling) and SFP N cooling (FLEX pump injection to SFP). Utilize initial RRC equipment in spare capacity.

Change 8 Attachment 3 -Conceptual Sketches Page 10 of33 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 Reason for Change: Changes to deployment plan and system alignments required updated sketches.

Change: Figures 1 through 7 of this document.

Change 9 Extent to which the guidance, JLD-ISG-2012-01 and NE112-06, are being followed.

Reason for Change: Address Open Item 3.2.4.8.A in the Clinton Interim Staff Evaluation.

Change: Extent to which the guidance, JLD-ISG-2012-01 and NEI 12-06, are being followed.

Identify any deviations to JLD-ISG-2012-01 and NEI12-06.

Ref: JLO-ISG-2012-01 NEI 12-06 13.1 The use of pre-staged FLEX generators is an acceptable alternate approach to NE112-06 and JLD-ISG-2012-01 for complying with Order EA-12-049 for the following reasons: The location chosen for pre-staging the generators is protected from each of the hazards delineated in NEI12-06.

The guidance Section 11.3.2 for storage of FLEX equipment provides for storing equipment such that it can be operated in place. Additionally, the portable and mounted electrical boxes and cables used to connect the FLEX generator to the installed 480 VAC distribution system are stored in accordance with NE112-06 Sections 5 through 9 in the same area as the generators.

The decision to pre-stage the generators in the location that would otherwise be the deployment destination provides the operators with the fewest challenges implementing the electrical strategy.

The Mark III containment strategy for Clinton requires 480 VAC power at to + 5.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> and suppression pool cooling in service using a FLEX pump to supply essential service water to an RHR heat exchanger in t o+ 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. Pre-staging the generators allows resources to be applied to establishing the required electrical and mechanical lineups that would otherwise be used deploying the generator from a remote location.

5 Need for Relief/Relaxation and Basis for the Relief/Relaxation Clinton Power Station expects to comply with the order implementation date and no relief/relaxation is required at this time. 6 Open Items from Overall Integrated Plan and Draft Safety Evaluation The following tables provide a summary of the open items documented in the Overall Integrated Plan or the Draft Safety Evaluation (SE) and the status of each item. Page 11 of 33 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 Overall Integrated Plan Open Item Status Initial calculations were used to determine the fuel pool timelines.

Formal [Not Started) calculations will be performed to validate this information during development of the spent fuel pool cooling strategy detailed design, and will be provided in a future six (6) month update. Analysis of deviations between Exelon's engineering analyses and the [Completed) analyses contained in BWROG document is expected to be completed, documented on Attachment lB, and provided to the NRC in the August 2013 six (6) month status update. The times to complete actions in the Events Timeline are based on operating

[Not Started) judgment, the conceptual designs, and the current supporting analyses.

The final timeline will be time validated once detailed designs are completed, procedures are developed, and the results will be provided in a future six (6) month update. Identification of storage locations and creation of the administrative

[Not Started) program are open items. Closure of these items will be documented in a six (6) month update. Habitability conditions will be evaluated and a strategy will be developed to Will be tracked under Confirmatory maintain Main Control Room habitability.

The strategy and associated Items 3.2.4.2.B and 3.2.4.6.A.

support analyses will be submitted in a future six (6) month update. [Closed) Battery room conditions will be evaluated and a strategy will be developed Will be tracked under Confirmatory to maintain acceptable conditions.

The strategy and associated support Item 3.2.4.2.A.

analyses will be submitted in a future six (6) month update. [Closed) Inverter room conditions will be evaluated and a strategy will be developed Will be tracked under Confirmatory to maintain acceptable conditions.

The strategy and associated support Item 3.2.4.2.C.

analyses will be submitted in a future six (6) month update. [Closed] The need for further analysis of fuel building conditions during an Will be tracked under Confirmatory ELAP/LUHS and mitigating actions is an open item. Closure of this item will Item 3.2.2.A. be documented in a future six (6) month update. [Closed) Procedures and programs will be developed to address storage structure

[Not Started) requirements, haul path requirements, and FLEX equipment requirements relative to the external hazards applicable to Clinton Power Station. Page 12 of 33 Item Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 Draft Safety Evaluation Open Items Description Status Number 3.1.4.2.C No information was provided in the Integrated Plan to The FLEX pump will take suction from address the ultimate heat sink and the potential that the an existing opening on the Screen flow path may be affected by ice blockage or formation of House deck that was designed for a frazil ice due to extreme low temperatures.

Unit 2 Shutdown Service Water (SX) Pump. This location bypasses the Unit 1 traveling screens and is not susceptible to frazil ice. It is not susceptible to ice blockage since the inlet to the Screen House is at elevation 670', 5 feet below the design water level of the UHS. The occurrence of an estimated ice thickness of 10" in the intake area when the water level is at elevation 675' would not block the flow into the Screen House. The availability of the FLEX pump water supply will not be affected by ice formation in the Screen House area. Additional protection against any probable ice blockage in the intake area is provided with the installation of a warming line at the inlet to the Screen House, designed to maintain a minimum water temperature of 40°F during winter operation.

[Complete]

3.2.4.8.A On page 6 of their six-month update, dated August 28, 2013 See Change 9 in this document. (Agencywide Documents Access and Management System [Complete] (ADAMS) ML 13241 A241), the licensee states that they are proposing to pre-stage both the primary and alternate FLEX generator in the Unit 2 side of the Control/Diesel Generator building.

This use of pre-staged generators appears to be an alternative to N EI 12-06. In a future submittal update the licensee will need to document the proposed method as an alternate to NEI12-06, along with a stronger justification addressing how the approach maintains the flexibility to respond to an undefined event and provide power to the necessary eqUipment.

Page 13 of 33 Item Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28,2014 Draft Safety Evaluation Confirmatory Items Description Status Number 3.1.1.1.A Each section of the Integrated Plan describing protection of See Attachment 2 of this document.

equipment from the hazards makes reference to NEI12-06, [Complete]

Section 11 rather than to the protection guidance described in NEI 12-06 for the applicable hazard; that is 6.2.3.1 for floods, 7.3.1 for wind, etc. The licensee's proposed protection strategy needs to be specific for each hazard. 3.1.1.2.A The Integrated Plan did not provide sufficient information The deployment plan for each of the to conclude that for each mitigation strategy discussed, mitigating strategies requires operators would have access only through seismically personnel access and hose/cable robust structures to deploy the strategy.

As an example, on routing through only seismically robust page 27 of the Integrated Plan, the deployment plan structures.

describes using hoses to connect the FLEX alternate

[Complete]

suppression pool cooling pump to the suppression pool and RHR heat exchanger connections.

licensee needs to address this issue generically.

3.1.1.2.8 It was not evident from the review of the Integrated Plan The design of the storage building at whether or not electrical power would be necessary to the Screen House will specify access move or to deploy mitigation strategies (e.g., to open the doors that can be manually operated.

door from a storage location).

If necessary, provisions If this proves to be impractical, then a would be necessary to provide that power source. portable generator will be stored in the building to provide the necessary electrical power. [Complete]

3.1.1.3.A The licensee should develop a reference source that Containment and Drywell temperature provides approaches for obtaining necessary instrument readings are included in the procedure readings for instruments in addition to the existing for obtaining Suppression Pool guidance for the suppression pool temperature instrument.

temperature readings.

The suppression pool cleanup and transfer pumps will Suppression Pool Cleanup and Transfer require a strategy to provide control power to the pump Pump supply breakers can be closed motor supply breakers.

manually without DC power. [Complete]

3.1.1.3.8 The licensee discussed how internal flooding is mitigated Results of internal flooding analysis will for ECCS pump cubicles, but it is not clear whether or not be included in the August 2014 update. other mitigation strategies may be susceptible to the [Started]

internal flooding hazard. 3.1.1.4.A With regard to the use of off site resources, no information Refer to Figure 7. The 8 Staging Area is was provided regarding the identification of the local arrival shown on the north side of the Page 14 of 33 3.1.2.1.A 3.1.2.2.A 3.1.2.2.B 3.1.2.3.A 3.1.4.2.A Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 staging area or a description of the methods to be used to property.

Two access routes into the deliver the equipment to the site. During the audit process, protected area are shown, and each of the licensee stated that information will be provided in a those routes can reach the A Staging future 6-month update to address the issue. Areas (Al for UHS access and primary water connection, A2 for an electrical and alternate water connection).

[Complete]

On page 4, in the section of its Integrated Plan regarding FLEX pumps and associated equipment key assumptions associated with implementation of FLEX will be stored in a robust structure at strategies, the licensee explained that primary and the Unit 2 side of the Screen House. secondary storage locations for FLEX equipment have not FLEX generators and associated cabling been selected.

Storage locations must be selected that will be stored in the robust Diesel protect FLEX equipment fro m all hazards. Generator, Control, and Auxiliary buildings.

[Complete]

With regard to deployment during flood conditions, the During flooding conditions the FLEX licensee stated that transportation routes from the pumps will be moved from the storage equipment storage area to the FLEX staging areas are not building at the Screen House and yet identified.

The licensee also stated that the relocated to higher ground, in advance identification of storage areas is part of a self identified of the rising lake level, on the Screen open item. House access road. (See Figure 7) [Complete]

The Integrated Plan did not address the potential need to Diesel powered trash pumps will be remove accumulated water from structures in the event stored in the robust Control Building.

that installed sump pumps are not available.

Accumulated water can be pumped to the unused Unit 2 Diesel Generator Fuel Oil Storage Tank rooms in the Diesel Generator Building basement.

[Complete]

The administrative program and procedures for The administrative program and deployment from storage and staging areas in flood procedures for deployment from conditions or after a tornado are not yet developed.

storage and staging areas in flood conditions or after a tornado will be described in a future 6-month update. [Not Started] The licensee does not address the effects of snow, ice, and All manual actions in the early hours of extreme cold on the ability of plant personnel to perform the event are performed indoors, manual operations.

either in the plant or in the FLEX storage building.

Appropriate clothing will be pre-staged for outdoor actions, such as refueling the FLEX DG and Page 15 of 33 3.1.4.2.B 3.2.1.1.A 3.2.1.1.B 3.2.1.1.C 3.2.1.1.0 3.2.1.1.E 3.2.1.3.A 3.2.1.4.A Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 Pump. [Complete]

Although debris removal and haul requirements are The site Snow Removal Plan will be addressed as previously discussed in this report, there is revised to staff appropriately when insufficient information in the Integrated Plan to conclude there is a significant threat to off-site the licensee will conform to guidance with respect to the power sources. removal of snow and ice from haul pathways and staging [Started]

areas. Need benchmarks to demonstrate that the Modular Information that validates the use Accident Analysis Program (MAAP4) is the appropriate code MAAP4 will be included in a future 6-for simulation of ELAP. month update. [Started]

Collapsed level must remain above Top of Active Fuel and Information that validates the use cool down rate must meet technical specifications.

MAAP4 will be included in a future 6-month update. [Started]

MAAP4 use must be consistent with June 2013 position Information that validates the use paper. MAAP4 will be included in a future 6-month update. [Started]

In using MAAP4, the licensee must identify and justify the Information that validates the use subset of key modeling parameters cited from Tables 4-1 MAAP4 will be included in a future 6-through 4-6 ofthe "MAAP4 Application Guidance, Desktop month update. Reference for Using MAAP4 Software, Revision 2" (Electric

[Started]

Power Research Institute Report 1020236).

The specific MAAP4 analysis case that was used to validate Information that validates the use the timing of mitigating strategies in the Integrated Plan MAAP4 will be included in a future 6-must be identified and should be available on the ePortal month update. for NRC staff to view. Alternately, a comparable level of [Started]

information may be included in the supplemental response.

f The sequence of events timeline is not final. The licensee Results of time line vaidation will be stated that the final sequence of events timeline will be included in a future 6-month update. time validated once detailed designs are completed and [Not Started] procedures are developed.

The licensee stated that the results will be provided in a future 6-month update. Also, the final sequence of events timeline needs to identify FLEX pump availability for RCIC backup when the FLEX pump is staged to supply backup for RCiC. included in Change 7 ofthis document.

[Complete] has not yet completed the analyses to FLEX pump flow analysis will be Page 16 of33 3.2.1.4.B 3.2.1.S.A 3.2.2.A 3.2.3.A 3.2.3.B 3.2.3.C Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 demonstrate adequate head and flow will be provided by included in a future 6-month update. the FLEX pumps for cooling strategies.

[Started]

The concerns related to raw water injection by FLEX Raw water flow to the RPV from LPCS strategies are being add ressed by the Boiling Water or RHR-C is directed inside the core Reactor Owners Group and the resulting evaluation will be shroud. The potential for blockage of included in a future 6-month update. fuel bundle flow orifices is minimized using these systems. Additionally, the procedure for low pressure RPV and suppression pool makeup will provide a prioritized list of cleaner water sources using equipment that may be available after the event has occurred.

[Complete]

Additional information is needed to address the associated The RFP for the FLEX generators will measurement tolerances/accuracy of instrumentation used specify the need to have to monitor portable/FLEX electrical power equipment to instrumentation and protection for the ensure that: 1) the electrical equipment remains protected generator.

This will remain open until (from an electrical power standpoint-e.g., power we have the final contract for the fluctuations) and 2) the operator is provided with accurate equipment.

information to maintain core cooling, containment, and [Startec:j]

spent fuel cooling. The licensee stated that evaluation of the spent fuel pool Evaluation of Spent Fuel Pool Area for area for steam and condensation had not yet been steam and condensation will be performed.

The results of this evaluation and the vent path included in a future 6-month update. strategy, if needed, will be provided in a future 6-month [Not Started] update. The licensee plans to circulate suppression pool water The plan to restore and maintain the through the shell side of an RHR heat exchanger using RHR piping to operable status will be abandoned RHR steam condensing mode piping. It is not provided in a future 6-month update. clear how the abandoned RHR piping used will be returned [Not Started] to an operable status. The licensee stated the plan to restore and maintain the RHR piping to operable status will be provided in a future 6-month update. It is not clear from the licensee's Integrated Plan that The plan for maintenance and testing current maintenance and testing for the suppression pool for the suppression pool cleanup and cleanup and transfer pumps would conform to the transfer pumps to conform to the standards for FLEX equipment because the pumps are not standards for FLEX equipment will be currently relied upon to mitigate accidents or transients or included in a future 6-month update. the consequences of a beyond-design-basis event. [Not Started] The expected peak temperatures predicted by MAAP4 The potential for wetwell air space calculations are 18S.06 degrees F for the wetwell air space temperatures exceeding the 18S0F and 2S3.8 degrees F for the drywell. The wetwell air space design limit will be included in a future Page 17 of33 3.2.4.2.A 3.2.4.2.B 3.2.4.2.C 3.2.4.2.0 3.2.4.4.A Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 peak is marginally above the 185 degree F limit for the 6-month update. containment.

Because there are unresolved concerns with [Started]

the MAAP4 analyses, the licensee will need to address the potential for wetwell air space temperatures exceeding the 185 degree F design limit. The information provided in the Integrated Plan regarding Battery room ventilation information battery room ventilation did not address potential regarding temperature and hydrogen temperature increases/decreases on the station batteries concerns will be provided in a future 6-due to loss of battery ventilation resulting from an ELAP. A month update. discussion is also needed on hydrogen limits in battery [Not Started] room while charging the batteries during Phase 2 and 3.The licensee stated that battery room ventilation information will be provided in a future 6-month update. The licensee stated on page 41 regarding phase 2 main Main Control Room cooling control room cooling that further analysis is needed to information will be provided in a develop strategies.

These strategies and supporting analysis future 6-month update. are to be provided in a future 6-month update [Not Started] On page 41, in the section of the Integrated Plan regarding Inverter Room cooling information will safety function support, phase 2, the licensee stated that be provided in a future 6-month inverter room conditions will be evaluated and a strategy update. will be developed to maintain acceptable conditions.

The (Not Started] strategy and associated support analyses will be submitted in a future 6-month update In general, the discussion of ventilation in the submittal The impact of elevated temperature provides insufficient information on the impact of elevated on equipment credited as part of the temperatures, as a result of loss of ventilation and/or ELAP strategies will be included in a cooling, on the support equipment being credited as part of future 6-month update. the ELAP strategies (e.g., electrical equipment in the RCiC [Not Starteq] pump rooms). As an example, there is no discussion regarding whether the initial temperature condition assumed the worst-case outside temperature with the plant operating at full power. No list was provided or referenced of electrical components located in the pump rooms that are necessary to ensure successful operation of required pumps. Also, no information was provided regarding the qualification level for temperature and pressure for these electrical components for the duration that the pumps are assumed to perform its mitigating strategies function.

During the audit process, the licensee explained that these issues will be addressed by providing information in a 6-month update. Confirm upgrades to communication system that resulted Upgrades to communication systems from the licensee communications assessment.

Reference that resulted from the communications Page 18 of 33 3.2.4.6.A 3.2.4.8.B 3.2.4.8.C 3.2.4.9.A Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 assessment correspondence (ADAMS Accession Nos. assessment will be confirmed in a ML 12306A199 and ML 13056A135).

future 6-month update. [Started]

On page 41 of the Integrated Plan, in the section describing Main Control Room habitability safety function support for phase 2, the licensee stated that information will be provided in a habitability conditions will be evaluated and a strategy will future 6-month update. be developed to maintain Main Control Room habitability.

[Not Started] On page 50, in the Integrated Plan, the submittal includes a The 500 KW "Low Voltage Diesel table that lists additional equipment, "Medium Voltage and Generator" will be connected to an Low Voltage Diesel Generators", for phase 3; however, this external electrical connection point equipment is not discussed in the body of the Integrated and will supply the 480 VAC electrical Plan. It is not clear from the information presented in the distribution system as shown in Figure plan regarding; when and how the "Medium Voltage and 4. The generator will serve as a Low Voltage Diesel Generators" identified in the table redundant source to the primary and would be used, what loads would be served, or what alternate generators staged at the site. generating capacity would be provided.

The licensee stated [Complete]

the strategies for the deployment of phase 3 equipment Guidance for deployment of planned would be developed and incorporated into pre-planned "Medium Voltage Diesel Generator" (4 guidance.

The guidance will provide flexible and diverse kV) generators will be included in a direction for the acquisition, deployment, connection, and future 6-month update. operation of the equipment.

[Not Started] The Integrated Plan does not provide information or The FLEX generator sizing calculations references regarding sizing calculations for the FLEX will be provided on the eportal for the generators to demonstrate they can adequately provide August 2014 update. power to the assumed loads. The licensee's response [Not Started] addressed this issue by stating that the FLEX generator sizing calculations will be submitted in a future 6-month update. The licensee did not address assessing and maintaining fuel Fuel oil quality concerns will be quality for fuel oil supplies to the FLEX equipment.

addressed in a future 6-month update. [Not Started] Also, the licensee did not address a concern with regard to The fuel oil strategy uses the installed providing an indefinite fuel supply. diesel generator storage tanks to replenish the FLEX diesel driven equipment.

The fuel oil level equivalent to a 7-day supply at the maximum post-LOCA load demand for the Division 1 Diesel Generator is 51,000 gallons (primary Page 19 of 33 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 strategy), for the Division 2 Diesel Generator is 45,000 gallons (alternate strategy).

The quantity of fuel oil required in either the primary or alternate strategy can be served by the respective fuel oil storage tank for well beyond 7 days. The Emergency Response Organization would be able to transfer fuel oil, if needed, from the opposite division, and another 29,500 gallons of fuel oil in the Division 3 storage tank could be used as well. [Complete]

3.4.A The Integrated Plan failed to provide any information as to Clinton has established a contract with how conformance with NEI12-06, Section 12.2 guidelines 2 Pooled Equipment Inventory Company through 10 will be met regarding the capabilities of the off (PEICo) and has joined the Strategic site resou rces. Alliance for FLEX Emergency Response (SAFER) Team Equipment Committee for off-site facility coordination.

The contract with SAFER addresses items in NE112-06 section 12.2. [Complete]

7 Potential Draft Safety Evaluation Impacts There are no potential impacts to the Draft Safety Evaluation identified at this time. 8 References The following references support the updates to the Overall Integrated Plan described in this enclosure.

1. Clinton Power Station's 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. 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. 3. BWROG report NEDC-33771P Rev 2, "GEH Evaluation of FLEX Implementation Guidelines Rev 2" 4. CL-IVIISC-009 Rev 3 MAAP Analysis to Support FLEX Initial Strategy 5. CPS 4402.01, EOP-6 PRIMARY CONTAINMENT CONTROL 6. 0000-0143-0382-R1, DRF 0000-0143-0380, "BWROG RetC System Operation in Prolonged Station Blackout -Feasibility Study" 7. Clinton UFSAR Section 8.1.3.4 Page 20 of33 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 8. CPS Drawing M05-1073, Sheet 001, Rev AG, LOW-PRESSURE CORE SPRAY (LPCS) (LP) 9. CPS Drawing M05-1075, Sheet 003, Rev AG, RESIDUAL HEAT REMOVAL (RH) 10. EC 391824 FLEX Battery Coping Study 9 Attachments

1. NSSS Significant Reference Analysis Deviation Table (Attachment 1B in the Overall Integrated Plan Report Template).

2. FLEX Equipment Protection per NE112-06 10 Figures 1. RCiC Operation During Phase 2 2. Suppression Pool Cooling and Low Pressure RPV Makeup from Suppression Pool 3. Supply from Ultimate Heat Sink 4. Electrical Strategy 5. FLEX ADS Air Supply 6. FLEX Fuel Oil Supply 7. FLEX Deployment Conceptual Sketch Page 21 of 33 Item Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28,2014 Parameter of Interest Attachment 1 NSSS Significant Reference Analysis Deviation Table (Attachment 1B in the Overall Integrated Plan Report Template)

NEDC-NEDC-33771P 33771P Design Rev 2 Value Page Plant Applied Value Value Gap and Discussion NEDC-33771P Rev 2 Appendix 5 is closest to the Clinton strategy for Maintaining Containment Integrity.

Differences between the GEH SHEX case and the MAAP analysis of the Clinton strategy are listed below. Input Parameter Values 1 Core thermal power Note 1 20 3473 MWT NA The GEH model BWR 6 Mark III plant has larger 2 Heat Sink Temperature Note 1 21 91.4 D F NA decay heat load than Clinton by 26.9%. 3 Primary System Leakage Note 1 20 100gpm NA The SHEX input parameter values for the GEH model plant differ in some cases from the 4 RPV Depressurization Rate Note 1 20 50 D F/hr NA MAAP input parameter values for Clinton due 5 Drywell Free Volume Note 1 20 215,000 ft3 NA to differences in assumptions and some design differences.

6 Initial Drywell Temperature Note 1 20 150 D F NA Despite these differences the SHEX case for 7 Initial Drywell Pressure Note 1 20 15.3 psi a NA the model plant and the MAAP case for Clinton 8 Initial Drywell Humidity Note 1 20 55% NA demonstrate the effectiveness of suppression pool cooling in reducing suppression pool 9 Wetwell Free Volume Note 1 20 1,512,341 ft3 NA temperature and stabilizing containment 10 Initial Wetwell Pressure Note 1 20 14.31 psi a NA pressure and temperature as shown in Figures 5-1,5-2, and 5-3 in NEDC-33771P Revision 2. 11 Suppression Pool Volume Note 1 20 130,000 ft3 NA 12 Containment Pool Volume Note 1 20 15,000 ft3 NA 13 Containment Pool Initial Note 1 20 100°F NA Temperature 14 Suppression Pool Temperature Note 1 20 95°F NA Page 22 of33 15 16 17 18 19 20 21 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 Heat Removal (BTU/sec-OF)

Note 1 21 200.8 -202.4 NA SHEX uses a heat removal constant to (BTU/hr)/(3600*(Supp Pool characterize the RHR heat exchanger.

MAAP Temp-RHR HX Shell Out uses Clinton specific RHR heat exchanger Temp))] details. The Clinton heat removal value was calculated from MAAP data for comparison . RCiC Suction Source Note 1 21 * < to + 8 hrs -Suppression NA In the Clinton strategy, RCiC suction is shifted Pool from the suppression pool to the RHR heat

• exchanger shell outlet at to + 8 hrs. This action exchanger outlet (138°F) limits the RCiC system exposure to elevated suppression pool water temperature.

Resultant Parameter Values Maximum Suppression Pool Note 1 33 209.44°F (to + 19.02 hrs) 185°F The decay heat load of the GEH model BWR 6 Temperature Mark III plant drives suppression pool Maximum Wetwell Temperature Note 1 33 185.06°F (to + 43.8 hrs) 185°F temperature to [Note 1] by the time suppression pool cooling is started at to + 8 Maximum Wetwell Pressure Note 1 33 24.9 psi a (to + 45.9 hrs) 29.7 hrs. This causes containment and drywell psi a pressure to reach a higher value than the Maximum Drywell Temperature Note 1 33 253.79°F (to + 71.7 hrs) 330°F Clinton strategy.

Maximum Drywell Pressure Note 1 33 29.12 psi a (to + 47.8 hrs) 44.7 In the Clinton strategy, suppression pool psia temperature is 200.5°F when cooling is started at to + 8 hrs. It continues to rise and peaks at 209.41 of at to + 19.02 hrs, when the heat transfer rate in the RHR heat exchanger matches the decay heat input. --'-----------Note 1: The NEDC-33771P Rev 2 values are proprietary but can be found on the referenced pages of the document.

Page 23 of 33 I Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 Attachment 2 FLEX Equipment Protection per NEI 12-06 5.3.1 Protection of FLEX Equipment (Seismic)

1. FLEX equipment should be stored in one or more of following three configurations:

a. In a structure that meets the plant's design basis for the Safe Shutdown Earthquake (SSE){e.g., FLEX equipment will be installed in existing safety-related structure).

structures designed to survive a SSE. b. In a structure designed to or evaluated equivalent to ASCE 7-10, Minimum Design Loads for NA Buildings and Other Structures.

c. Outside a structure and evaluated for seismic interactions to ensure equipment is not damaged by NA non-seismically robust components or structures.

2. Large portable FLEX equipment such as pumps and power supplies should be secured as appropriate FLEX pumps and generators will be to protect them during a seismic event (Le., Safe Shutdown Earthquake (SSE) level). installed to survive a SSE. 3. Stored equipment and structures should be evaluated and protected from seismic interactions to FLEX equipment will be protected and ensure that unsecured and/or non-seismic components do not damage the equipment.

stored in areas where the potential for seismic interactions with unsecured and/or non-seismic equipment is minimal. 6.2.3.1 Protection of FLEX Equipment (Flooding)

These considerations apply to the protection of FLEX equipment from external flood hazards: 1. The equipment should be stored in one or more of the following configurations:

a. Stored above the flood elevation from the most recent site flood analysis.

The evaluation to FLEX equipment will be stored above determine the elevation for storage should be informed by flood analysis applicable to the site the PMF elevation with the exception from early site permits, combined license applications, and/or contiguous licensed sites. of the FLEX pumps and associated equipment, and the haul/debris removal vehicle. b. Stored in a structure designed to protect the equipment from the flood. NA c. FLEX equipment can be stored below flood level if time is available and plant FLEX pumps and associated equipment, procedures/guidance address the needed actions to relocate the equipment.

Based on the timing of the limiting flood scenario{s), the FLEX equipment can be relocated to a position that is and the haul/debris removal vehicle protected from the flood, either by barriers or by elevation, prior to the arrival of the potentially will be stored below the PMF elevation.

damaging flood levels. This should also consider the conditions on-site during the increasing flood Procedures governing high lake level levels and whether movement of the FLEX equipment will be possible before potential inundation will include guidance for relocating this occurs, not just the ultimate flood height. equipment ahead of rising lake level. Page 24 of33 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 2. Storage areas that are potentially impacted by a rapid rise of water should be avoided. Rapid rise in lake level is not a credible event. 7.3.1 Protection of FLEX Equipment (Wind) These considerations apply to the protection of FLEX equipment from high wind hazards: 1. For plants exposed to high wind hazards, FLEX equipment should be stored in one of the following configurations:

a. In a structure that meets the plant's design basis for high wind hazards (e.g., existing safety-FLEX equipment will be installed in related structure).

structures that will survive the design basis wind. b. In storage locations designed to or evaluated equivalent to ASCE 7-10, Minimum Design Loads for Buildings and Other Structures given the limiting tornado wind speeds from Regulatory Guide 1.76 or design basis hurricane wind speeds for the site. Given the FLEX basis limiting tornado or hurricane wind speeds, building loads would be computed in accordance with requirements of NA ASCE 7-10. Acceptance criteria would be based on building serviceability requirements not strict compliance with stress or capacity limits. This would allow for some minor plastic deformation, yet assure that the building would remain functional.

• Tornado missiles and hurricane missiles will be accounted for in that the FLEX equipment will be stored in diverse locations to provide reasonable assurance that N sets of FLEX equipment will remain deployable following the high wind event. This will consider locations adjacent to NA existing robust structures or in lower sections of buildings that minimizes the probability that missiles will damage all mitigation equipment required from a single event by protection from adjacent buildings and limiting pathways for missiles to damage equipment.

• The axis of separation should consider the predominant path of tornados in the geographical location.

In general, tornadoes travel from the West or West Southwesterly direction, diverse locations should be aligned in the North-South arrangement, where possible.

Additionally, in NA selecting diverse FLEX storage locations, consideration should be given to the location of the diesel generators and switchyard such that the path of a single tornado would not impact all locations.

• Stored mitigation equipment exposed to the wind should be adequately tied down. Loose equipment should be in protective boxes that are adequately tied down to foundations or slabs to prevent protected equipment from being damaged or becoming airborne. (During a NA tornado, high winds may blow away metal siding and metal deck roof, subjecting the equipment to high wind forces.) c. In evaluated storage locations separated by a sufficient distance that minimizes the probability NA --Page 25 of33 I Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 that a single event would damage all FLEX mitigation equipment such that at least N sets of FLEX equipment would remain deployable following the high wind event. (This option is not applicable for hurricane conditions).

• Consistent with configuration b., the axis of separation should consider the predominant path of tornados in the geographical location.

NA

• Consistent with configuration b., stored mitigation equipment should be adequately tied NA down. 8.3.1 Protection of FLEX Equipment (Snow, Ice, Cold) These considerations apply to the protection of FLEX equipment from snow, ice, and extreme cold hazards: 1. For sites subject to significant snowfall and ice storms, portable FLEX equipment should be stored in one of two configurations:

a. In a structure that meets the plant's design basis for the snow, ice and cold conditions (e.g., FLEX equipment will be installed in existing safety-related structure).

structures that will survive the design basis for snow, ice, and cold. b. In a structure designed to or evaluated equivalent to ASCE 7-10, Minimum Design Loads for NA Buildings and Other Structures for the snow, ice, and cold conditions from the site's design basis. c. Provided the N FLEX equipment is located as described in a. or b. above, the N+l equipment may be stored in an evaluated storage location capable of withstanding historical extreme weather NA conditions and the equipment is deployable.

2. Storage of FLEX equipment should account for the fact that the equipment will need to function in a FLEX pumps and generators and their timely manner. The equipment should be maintained at a temperature within a range to ensure its likely function when called upon. For example, by storage in a heated enclosure or by direct heating storage location will include (e.g., jacket water, battery, engine block heater, etc.). appropriate heating. 9.3.1 Protection of FLEX Equipment (High Temperature)

The equipment should be maintained at a temperature within a range to ensure its likely function when called FLEX pumps, generators, and the upon. haul/debris removal vehicle, and their storage locations will include appropriate cooling such that the equipment will run without overheating.

Page 26 of 33 Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 Figure 1 RCIC Operation During Phase 2 Cnmt UpperCnmt UH5 OWl Sl! -Page 27 of 33 Spray Pool Keel'"FiIl Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28,2014 Figure 2 Suppression Pool Cooling and low Pressure RPV Makeup from Suppression Pool Cnmt Spray Upper Cnmt Pool RCIC Suction To Turbine Bldg ("J" Suppression Pool Letdown IA IA UHS l5F009 l5FOll Div 1 SX Supply l5F010A From RHR-A Pump 15F01PA Suppression Pool Cleanup Pumps 1750 gpm, 230' head Page 28 of33 Feedwater Keep-Fill lE12-F49l lEH-FOllA lE12-F024A lE12-f042A LPCI Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 Figure 3 Supply from Ultimate Heat Sink " "

"",,,Une --l)I(1 tit II' lPCSlnjO<1iontORI'V Bfad lines depict permanent plant equipment Red lines deplcl flEX eqUipment Dotted lines depict manually deployed lE12,f{)l48 i :l! i .. 15X354B lE12-F0688

................ "

Opoen!"c ./' to OUI;$lde * * * * * * * * * * .. Unit 2 DIY 2 SX Burlttd 30-Supply UI'W! Page 29 of33 U>IS " c; 1E12*F06aA lElZ-f-l114A .. I'.! {i J

• • :::::.:::::::

• • Existing Plant Equipment Pre-Installed Cable Runs Cable Spools Spooled Cable Runs Spare Cubkle Inserts Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28,2014 Figure 4 Electrical Strategy 1> ...... * + +. IF)(OllCA Primary FLEX ,: "u .. lFX01KB Alternate FLEX . . Generator : Generator

... .+ ... -."J0. t .... --

._._---, ... -'" : : RRC Generator

/irK Pre-Installed Terminal Boxes -, PIHT't 1 f'vR RCO}nncc\l{10 e:: *

• ..............*

Primary Strategy Alternate Strategy *' ! i . " .. .. : 4160 VAC SWltf 1Al 4160 VAC Swgr 1B1 416""OVA( l rt!!!:1 :. * *

• I

• 8 J::. 4160{480V" 4160/480 VA' f 1

• I ..........

w ... __ w_ .. .... : L... . .! ...... ,+; ........ -.:J-.. .. ' .... I .:.......

• ** ='W! '" Hi I * : * ( rllTd !rid. ... "'.. I 1 : * ""'i-*> ............

-,., ..................

-.............

.1 I' : : ..........................

-_ ........... .

• i l , .! :'" "-1! ", I* ".j .....................................................

-....................................

-... -......................

.., ...... * ..... -... -.. tit .. .. ..... t ..................................................

S I, 8 ...................

--........ -..... -..................

,! li-.. ..J.

• I: : .! i : l .. * ! 6900 VAC Swgr lA i" *** '_ !;_. *** i ....... -... -.. --...........

-........

': ;t.. ...,!sa--, 6900 VAC Swgr 19 6900/4S0VAC -r 6900/480VAC I **1 6900/480 VAC -.-6900/480 VAC i,'" "-1-It ...... "" .........

""", ... ""-.. .. ,,.. ..-rr ... --..............

--1 . : ..... .. .... : "t : i ...................................

: It. _.-f . l 1 or 1! : : : ., . . . :: : : : ...

• i t : : -----: ' : .. -----_ ... _-....... _ ..........................................

_ .. _-* * , I";': * * * : : * * * * * * . '" .....................

,., ..........

_ ....... ,.. ...........................................

_ ......................

'" ... '" -"' .. !. .........................................

_--.. ----_ ..... --_ ..........

-_ ...... --_ ... -_ .... 1 I

• I I I *

• I t I

• I * , I I I * * * * * , *

• t * * * , I

• I *

• t *

• I *

• e I * * ,

• I I Page 30of33 -------------........*

ADS Backup Air Bottles Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 1DG011B 1DG01CA Air Dryers Bypassed 1DG011A 'IDG01CB Figure 5 FLEX ADS Air Supply 1DG168 "',..,..

.........

.....

.. .,...,,,.

....... "G'oo ............... . 1DG154 /------1 1DG04TA Division 1 (Division 2 Similar) 1DG169 /------1 1DG04TB 11A044A 1 B21-F051C 1B21-F051G 1B21-F047A 1 B21-F047C 1 B21-F041C Outside Fill Connection To SRVs 11A013A To SRVs 11A012A Page 31 of33 1DG625 1DG02MB !It ..... . .,.",,,,,'" ",,,,,,,,, .. ,,,, " 1 B21-F041 B 1 B21-F041 F 1 B21-F041D 1 B21-F051D 11A044B 1DG152 1DG153 * ",,,,,,,,,,, .. ,,,,,,,,,,,,,, "'oP" ... "',§ .' . , , . . * * * * * *

• iTo DG Air Start . " Motors ADS Backup Air Bottles Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 Figure 6 flEX Fuel Oil Supply 1 1 1 'Day Tank supplied from the DG Fuel Oil Storage Tank using the installed Fuel Oil Transfer Pump, powered from the FLEX DG Unit 1 Div 1 DG Room Portable 120 VAC Pump (using receptacle , ***.* wered from FJ:.£X . DG) :// Connection to FLEX Truck Fuel Tanks Unit 1 Div 2 DG Room Unit 2 Div 1 DG Room Page 32 of 33 1 Unit 2 Div 2 DG Room External connection from FLEX DG on 762'elevation Clinton Power Station's Second Six Month Status Report for the Implementation of FLEX February 28, 2014 Figure 7 FLEX Deployment Conceptual Sketch

• Ai Staging Area Storage building housing the prestaged FLEX pumps, hose trailers, and F-750 truck used for debris removal. Operators need to travel on foot to this location to gain access to the building to lineup the FLEX pump.

• A2 Staging Area External water and electrical connection used for RRC redundant equipment, and is the location of the source offuel oil to refill the FLEX pumps.

• Pedestrian Travel Route Personnel travelling on foot to the Al Staging Area follow a route that includes areas 3, 4, 5, and 1. The primary or alternate vehicle routes can be used as well.

• Phase 2 Primary Vehicle Travel Route The primary travel route between Al and A2 Staging Area includes areas 1, 2, 3, and 4.

• Phase 2 Alternate Vehicle Travel Route ---The alternate travel route between Al and A2 Staging Area includes areas 1, 5, 6, 2, 3, and 4.

• 8 Staging Area The laydown area for Phase 3 equipment arriving from the RRC or other locations.

• Phase 3 Primary Vehicle Travel Route The primary travel route from the B staging area to the Al and A2 staging areas includes area 7 before it connects to the on-site deployment route.

• Phase 3 Alternate Vehicle Travel Route ---The alternate travel route from the B staging area to the Al and A2 staging areas includes area 8 before it connects to the on-site deployment route. Page 33 of 33