ML14251A016

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 Number EA-12-049)

ML14251A016
Person / Time
Site:	Millstone
Issue date:	08/28/2014
From:	Mark D. Sartain Dominion, Dominion Nuclear Connecticut
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
14-393, EA-12-049
Download: ML14251A016 (42)

Text

Dominion Nuclear Connecticut, Inc.

5000 Dominion Boulevard, Glen Mien, VA 23060 Dominion Web Address: www.dom.com 10 CFR 2.202 EA- 12-049 August 28, 2014 Attention: Document Control Desk Serial No.: 14-393 U.S. Nuclear Regulatory Commission NL&OS/MAE: R1 Washington, D.C. 20555-0001 Docket No.: 50-336 License No.: DPR-65 DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 2 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 NUMBER EA-12-049)

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. Dominion Nuclear Connecticut, Inc.'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 (Serial No. 12-1611B)

3. Dominion Nuclear Connecticut, Inc.'s 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 Number EA-12-049), dated February 28, 2014 (Serial No. 12-161E)

On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued an order (Reference 1) to Dominion Nuclear Connecticut (DNC). Reference 1 was immediately effective and directed DNC to develop, implement, and maintain guidance and strategies to maintain core cooling, containment, and spent fuel pool cooling capabilities in the event of a beyond-design-basis external event.

Reference 1 required submission of an Overall Integrated Plan (OIP) (Reference 2) pursuant to Section IV, Condition C. Reference 1 also required submission of a status report at six-month intervals following submittal of the OIP. to this letter provides the third six-month status report and an update of milestone accomplishments since the submittal of the previous six-month status report

Serial No.14-393 Docket Nos. 50-336 Order EA-12-049 Page 2 of 3 (Reference 3), including any changes to the compliance method, schedule, or need for relief and the basis. provides the ventilation strategy, identified as Open Item 19 for the OIP.

This information is provided in the template format used for the originally submitted OIP.

The pages provided in Attachment 2 for Section F5, "Safety Function Support (Ventilation)," supersede Section F5 in the originally submitted OIP.

If you have any questions, please contact Ms. Margaret Earle at (804) 273-2768.

Sincerely, Mark D. Sartain Vice President - Nuclear Engineering Attachments (2)

Commitments made by this letter: No new Regulatory Commitments COMMONWEALTH OF VIRGINIA COUNTY OF HENRICO The foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today by Mark D. Sartain who is Vice President Nuclear Engineering of Dominion Nuclear Connecticut, Inc. He has affirmed before me that he is duly authorized to execute and file the foregoing document in behalf of the Company, and that the statements in the document are true to the best of his knowledge and belief.

Acknowledged before me this 2 7fday of, .AvIjQ*/, 2014.

My Commission Expires: 5- _31 J (Notary Public (SEAL) commonwuoft Ofl"0 Reg-# 140542 Comm~u60f Eprsmay 31, 2016

Serial No.14-393 Docket Nos. 50-336 Order EA-12-049 Page 3 of 3 cc: Director of Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission One White Flint North Mail Stop 13H116M 11555 Rockville Pike Rockville, MD 20852-2738 U. S. Nuclear Regulatory Commission, Region I Regional Administrator 2100 Renaissance Blvd.

Suite 100 King of Prussia, PA 19406-2713 Mr. M. C. Thadani NRC Senior Project Manager Millstone Units 2 and 3 U. S. Nuclear Regulatory Commission One White Flint North Mail Stop 08 B1 11555 Rockville Pike Rockville, MD 20852-2738 NRC Senior Resident Inspector Millstone Power Station

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Six-Month Status Report for the Implementation of Order EA-1 2-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events August 2014 Millstone Power Station Unit 2 Dominion Nuclear Connecticut, Inc. (DNC)

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 1 of 29 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 1 Introduction Dominion Nuclear Connecticut, Inc. (DNC) developed an Overall Integrated Plan (OIP)

(Reference 1), documenting the diverse and flexible strategies (FLEX) for Millstone Power Station Unit 2 (MPS2) in response to NRC Order Number EA-12-049 (Reference 2). This attachment provides an update of milestone accomplishments and open items since the last status report (Reference 16), including any changes to the compliance method, schedule, or need for relief/relaxation and the basis, if any.

2 Milestone Accomplishments The following milestones have been completed since the development of the OIP, and are current as of July 31, 2014.

• Submit Integrated Plan

" Develop Strategies

" Develop Training Plan

• Purchase Equipment

• Create Maintenance Procedures 3 Milestone Schedule Status The following table provides an update to Attachment 2A of the OIP. It provides the activity status of each item as of July 31, 2014, and whether the expected completion date has changed. The dates are planning dates subject to change as design and implementation details are developed.

The revised milestone target completion dates for 'Develop Modifications,' 'Implement Modifications,' 'Implement Training,' 'Issue FSGs and Associated Procedure Revisions,'

'Receive Equipment,' and 'Create Maintenance Procedures' do not impact the Order implementation date.

Target Activity Revised Target Milestone Completion Atity Revise Tare Date Status Completion Date Submit Integrated Plan February 2013 Complete Develop Strategies April 2014 Complete Develop Modifications July 2014 Started December 2014*

Implement Modifications August 2014 Started October 2015*

Develop Training Plan April 2014 Complete

Serial No.14-393 Docket No. 50-336 Order EA-1 2-049 Attachment 1 Page 2 of 29 Target Activity Revised Target Milestone Completion Status Completion Date Date__ _ _ _ _ _ _ _ _ _ _ _ _ _

Implement Training August 2014 Started April 2015*

Issue FLEX Support Guidelines and September Started July 2015*

Associated Procedure Revisions 2014 Develop Strategies/Contract with National SAFER Response Center August 2014 Started (NSRC)

Purchase Equipment February 2014 Complete Receive Equipment August 2014 Started September 2014*

Validation Walk-throughs or December Demonstrations of FLEX Strategies 2014 Not Started and Procedures Create Maintenance Procedures* August 2014 Complete Outage Implementation October 2015 Not Started Refer to Section 8, Supplemental Information, for an explanation of the change to this Milestone.

4 Changes to Compliance Method By letter dated February 28, 2013, (Reference 1), DNC provided an OIP to address Beyond-Design-Basis (BDB) events at MPS2 and Millstone Power Station Unit 3 (MPS3) as required by Order Number EA-12-049, dated March 12, 2012. The first Six-Month Status Update of the OIP for MPS2 and MPS3 was provided by letter dated August 23, 2013 (Reference 14). The second Six-Month Status Update for MPS2 was provided by letter dated February 28, 2014 (Reference 16). The following are changes to the compliance method information provided in the MPS2 OIP and subsequent updates, which continues to meet Nuclear Energy Institute (NEI) 12-06 (Reference 3):

a) Regarding the previously reported strategy for Modes 5 & 6, credit was taken for the Refueling Water Storage Tanks (RWSTs) to provide a borated water source for injection into the Reactor Coolant System (RCS). Although the RWSTs are not missile protected, credit as a borated water source was based on the assumption that it was improbable that both tanks would be destroyed by a single tornado. Subsequently, the strategy has been enhanced to address the scenario that both RWSTs are unavailable. The revised strategy includes the provision to utilize other water sources onsite (which are protected from a tornado) if both RWSTs are unavailable. If a clean water source is used, flow must be controlled in order to match the rate of water loss (due to boiling) so that dilution of the boron concentration in the RCS does not occur.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 3 of 29 b) Based on a study that included a chemical analysis of the various water sources onsite, the preferred order of clean water sources for use in both the primary and secondary sides of the Nuclear Steam Supply System (NSSS) was revised. Additionally, use of water from Long Island Sound or the onsite pond following a flooding event have been excluded as water sources for either the primary or secondary sides of the NSSS since they contain high concentrations of salt. As a last resort, however, they are not excluded as a water source for the Spent Fuel Pool.

c) DNC is pursuing an alternate means of compliance to NEI 12-06, Section 3.2.2, regarding additional "spare" cables and hoses. Typically, the hoses utilized to implement a FLEX strategy are not a single continuous hose, but are composed of individual sections of a smaller length joined together to form a sufficient length. In the case of cables, multiple individual lengths of cable are used to construct a circuit.

Hoses and cables are passive devices, that are unlikely to fail provided they are appropriately inspected and maintained. The most likely cause of failure is mechanical damage during handling provided that the hoses and cables are stored in areas with suitable environmental conditions. The hoses and cables for the FLEX strategies will be stored and maintained in accordance with manufacturers' recommendations including any shelf life requirements. Initial inspections and periodic inspections or testing/replacement will be incorporated into the site's maintenance and testing program and implemented in accordance with Section 11.5 of NEI 12-06.

The industry has proposed for NRC Staff consideration alternate methods of compliance to the N+1 requirement applicable to hoses and cables, as stated in Section 3.2.2 of NEI 12-

06. DNC supports this industry proposal and has adopted the agreed upon method for hoses in that 10% of the total length and at least one of the longest single lengths for each hose size has been purchased. With regard to cables, the 120/240VAC generators and the 480VAC generators are backups to each other; therefore, only N sets of cables are required. Consequently, once NRC endorsement of this alternate approach is complete, DNC will have achieved alternate compliance with the NEI 12-06 N+1 requirement for hoses.

d) The structural integrity of the reactor Containment building will not be challenged due to increasing Containment pressure during a BDB Extended Loss of AC Power (ELAP) event.

Additionally, analysis has shown that any increase in temperature following an ELAP event does not challenge the key parameter instrumentation in the Containment for at least seven (7) days.

Multiple Containment cooling methods described in previous submittals are available as options for heat removal to maintain Containment temperature for equipment design limits.

However, they are not required to be specifically designated as primary and alternate strategies. Adequate time is available utilizing equipment from the NSRC to deploy the cooling methods described.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 4 of 29 e) The BDB and NSRC equipment details in OIP Table 1, PWR Portable Equipment Phase 2, and OIP Table 2, PWR Portable Equipment Phase 3, respectively, have changed. Updates to the 'List Portable Equipment,' are included as well as associated changes/deletions in footnotes. Minor changes to the number of components have been included for some of the support equipment categories, but no changes have been made to the quantities of any of the major FLEX components. Revised OIP Tables 1 and 2 are attached.

5 Need for Relief/Relaxation and Basis for the Relief/Relaxation DNC expects to comply with the order implementation date and no relief/relaxation is required at this time.

6 Open Items The NRC has established an audit process to allow the exchange of information between the licensees and the NRC Staff (Reference 19). Between July 21, 2014 and July 25, 2014, MPS2 and MPS3 were the subject of an NRC onsite audit where the site specific aspects of DNC's proposed FLEX Mitigating Strategies were reviewed. During this NRC onsite audit, the staff reviewed site specific documentation and, upon completion of the audit, indicated that further review of several items was not anticipated as DNC proceeds towards compliance for Orders EA-12-049 and EA-12-051. These items are identified in the following tables in Section 6.

Note that the tables provided in Sections 6.4 and 6.5 are new and are the result of the ongoing NRC audit process.

6.1. Open Items from Overall Integrated Plan The following table provides a summary of the status of Open Items (01) identified by DNC and documented in Attachment 2B of the MPS2 Overall Integrated Plan submitted on February 28, 2013 and the status of each item.

Overall Integrated Plan Open Items 01 # Description Status Verify response times listed in timeline Started 1 and perform staffing assessment.

Scheduled completion date: December 2014 Preliminary analyses have been Complete.

performed to determine the time to steam generator (SG) overfill without (Reference 4) operator action to reduce Auxiliary Feedwater (AFW) flow, time to SG During the July 2014 NRC Onsite Audit, the dryout without AFW flow, and time to NRC Staff indicated that further review of depletion of the Condensate Storage this item was not anticipated as DNC Tank (CST). Final durations will be proceeds towards compliance for Orders EA-provided when the analyses are 12-049 and EA-12-051.

completed. I

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 5 of 29 Overall Integrated Plan Open Items 01 # Description Status Analyses will be performed to develop Complete.

fluid components performance requirements and confirm fluid The hydraulic calculation for the FLEX pumps hydraulic-related strategy objectives deployed using their associated hose can be met. networks have confirmed that the primary and the alternate connections for core cooling/decay heat removal, RCS Inventory, and reactivity control (RCS Injection), and Spent Fuel Pool (SFP) make-up strategies can be satisfactorily accomplished in 3 response to an ELAP/Loss of Ultimate Heat Sink (LUHS) event. (Reference 8)

Hydraulic calculations have confirmed that the SW flows for the Containment cooling options are adequate. (Reference 8)

During the July 2014 NRC Onsite Audit, the NRC Staff indicated that further review of this item was not anticipated as DNC proceeds towards compliance for Orders EA-12-049 and EA-12-051.

A study is in progress to determine the Complete.

design features, site location(s), and number of equipment storage facilities. A single 10,000 sq. ft. Type 1 building is being The final design for BDB equipment constructed at MPS for storage of BDB storage will be based on the guidance equipment. The building is designed to meet contained in NEI 12-06, Section 11.3, the plant's design basis for the Safe Shutdown Equipment Storage. A supplement to Earthquake, high wind hazards, snow, ice and this submittal will be provided with the cold conditions, and is located above the flood results of the equipment storage study. elevation from the most recent site flood analysis.

The BDB Storage Building is sited south of the railroad bridge, on the west side of the MPS access road, adjacent to the existing northeast contractor parking lot.

(References 13 and 17)

FLEX Support Guidelines (FSGs) will Started.

be developed in accordance with 5 PWROG guidance. Existing Scheduled completion date: July 2015*

procedures will be revised as necessary to implement FSGs.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment I Page 6 of 29 Overall Integrated Plan Open Items 01 # Description Status Electric Power Research Institute Complete.

(EPRI) guidance documents will be used to develop periodic testing and EPRI guidance documents have been used, preventative maintenance procedures where available, to develop the testing and for BDB equipment. Procedures will be preventative maintenance strategies for all sites.

developed to manage unavailability of Fleet-wide templates have been developed and equipment such that risk to mitigating input into the individual site maintenance strategy capability is minimized, strategies. Specific Periodic Maintenance (PM) procedures based on these strategies will be 6 implemented prior to the required MPS2 compliance date for Order EA-12-049.

A fleet-wide FLEX Strategy Program Document has been developed (Refer to Open Item 7).

The program includes the requirement to manage unavailability of equipment such that risk to mitigating strategy capability is minimized. A fleet-wide procedure has been developed to specifically address equipment unavailability. (Reference 20)

An overall program document will be Complete.

developed to maintain the FLEX strategies and their bases, and provide During the July 2014 NRC Onsite Audit, the 7 configuration control and change NRC Staff indicated that further review of management for the FLEX Program. this item was not anticipated as DNC proceeds towards compliance for Orders EA-12-049 and EA-12-051.

(Reference 21)

The DNC Nuclear Training Program Complete.

will be revised to assure personnel proficiency in the mitigation of BDB During the July 2014 NRC Onsite Audit, the 8 events is developed and maintained. NRC Staff indicated that further review of These programs and controls will be this item was not anticipated as DNC developed and implemented in proceeds towards compliance for Orders EA-accordance with the Systematic 12-049 and EA-12-051.

Approach to Training (SAT). (Reference 19)

Complete.

Confirm consistency of the FLEX The Combustion Engineering (CE) Owners steies c ithenyPWROG evaluation Group has issued generic guidelines to strategies with theACROGwevalat address plant response for post-loss of all AC 9 of post-loss of all AC power plant pwrfrCmuto niern lns response for Combustion Engineering power for Combustion Engineering plants.

rpoantse Based on these guidelines, DNC has plants, developed plant specific FSGs for MPS2 to address plant response for post-loss of all AC power. Specifically, depressurization of SGs

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 7 of 29 Overall Integrated Plan Open Items 01 # Description Status to a plant specific value of a target SG pressure to prevent Safety Injection Tank (SIT) nitrogen injection.

(Reference 7)

Develop strategy for use of the BDB Complete.

AFW Pump to provide SG injection in the unlikely event of loss of TDAFW In accordance with storm preparation 10 pump due to hurricane related storm procedures, one BDB AFW pump will be surge flooding of the Turbine Building. deployed early in the MPS2 Turbine Building Truck Bay.

(Reference 17)

Plant modifications will be completed Started.

for permanent plant changes required for implementation of FLEX strategies. Scheduled completion date: See Milestone Schedule above.

Complete.

Complete the engineering evaluation of The evaluation identified the need for a plant 12 the main steam atmospheric dump modification to the ADV outlet lines. The valve (MS ADV) outlet lines, identified modification is included in Open Item 11.

(Reference 22)

Complete.

Complete the evaluation of TDAFW 13 pump long term operation with < 120 TDAFW pump operation and adequate AFW psig inlet steam pressure. flow to the SGs at SG pressures < 120 psig has been confirmed. (References 5 and 6)

The Phase 3 coping strategy to Complete.

maintain Containment integrity is under development. Methods to monitor and During the July 2014 NRC Onsite Audit, the 14 evaluate Containment conditions and NRC Staff indicated that further review of depressurize/cool Containment, if this item was not anticipated as DNC necessary, will be provided in a future proceeds towards compliance for Orders EA-update.12-049 and EA-12-051.

(References 16 and 17)

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 8 of 29 Overall Integrated Plan Open Items 01 # Description Status Analyses will be performed to develop Complete.

electrical components performance requirements and confirm electrical Calculations have been completed for the loading-related strategy objectives can sizing and loading analysis of the 120VAC, be met. 480VAC, and 4160 VAC generators and confirm the electrical loading-related strategy 15 objectives can be met (Reference 11).

During the July 2014 NRC Onsite Audit, the NRC Staff indicated that further review of this item was not anticipated as DNC proceeds towards compliance for Orders EA-12-049 and EA-12-051.

Complete.

An evaluation of all BDB equipment An evaluation of all BDB equipment fuel 16 fuel consumption and required re-fill consumption and required refill strategies has strategies will be developed, been completed and provided as part of the ongoing NRC audit process.

(Reference 17)

A lighting study will be performed to Complete.

validate the adequacy of supplemental lighting and the adequacy and A lighting study has been completed validating practicality of using portable lighting to the adequacy of supplemental lighting and the 17 perform FLEX strategy actions. adequacy and practicality of using portable lighting to perform FLEX Strategy actions.

This was provided as part of the ongoing NRC audit process.

(Reference 17)

A comprehensive study of Complete.

communication capabilities is being performed in accordance with the A study documenting the communications commitments made in DNC letter S/N strategy has been completed. The study 12-205F dated October 29, 2012 in concludes that effective implementation of the response to Recommendation 9.3 of FLEX strategies will include the use of satellite the 10 CFR 50.54(f) letter dated March phones and hand-held radios. The study 18 12, 2012. The results of this study will acknowledges that MPS2 does not have a identify the communication means sound-powered phone system or equivalent available or needed to implement and that radio usage is limited (Reference 9).

command and control of the FLEX Accordingly, the tabletop assessment of the strategies at Millstone. Validation of FLEX strategies performed as part of the communications required to implement Phase 2 Staffing study has identified that the FLEX strategies will be performed as coordination of command and control of the part of Open Item No. 1. FLEX strategies will require the use of dispatched personnel.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 9 of 29 Overall Integrated Plan Open Items 01 # Description Status Details of the ventilation strategy are Complete.

under development and will conform to 19 the guidance given in NEI 12-06. The See Attachment 2, OIP Section F5 - Safety details of this strategy will be provided Functions Support (Ventilation).

at a later date.

Preferred travel pathways will be Complete.

determined using the guidance contained in NEI 12-06. The pathways The soil liquefaction study has been 20 will attempt to avoid areas with trees, completed (Reference 12), which supports the power lines, and other potential location of the storage building and the haul obstructions and will consider the routes. The results will be included with the potential for soil liquefaction, final design package for the storage building (Reference 13).

The equipment listed in Table 1 will be Started.

21 received on site. Scheduled completion date: September 2014*

• Refer to Section 8, Supplemental Information, for an explanation of the change to this Open Item.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 10 of 29 6.2. Open Items from Interim Staff Evaluation (ISE)

The following table provides a summary of the Open Items (01) from the MPS2 Interim Staff Evaluation (Reference 15) and the status of each item.

Interim Staff Evaluation Open Items 01 # Description Status 3.2.1.8.A Core Subcriticality and Boron Mixing: The Complete.

PWROG submitted to NRC a position paper, dated August 15, 2013, which provides test During the July 2014 NRC Onsite data regarding boric acid mixing under single- Audit, the NRC Staff indicated that phase natural circulation conditions and further review of this item was not outlined applicability conditions intended to anticipated as DNC proceeds ensure that boric acid addition and mixing towards compliance for Orders would occur under conditions similar to those EA-12-049 and EA-12-051.

for which boric acid mixing data is available. (References 17 and 19)

During the audit process, the licensee informed the NRC staff of its intent to abide by the generic approach discussed above. The licensee should address the clarifications in the NRC endorsement letter dated January 8, 2014.

!3.2.4.1.A The licensee did not provide sufficient This ISE 01 has been addressed as information regarding cooling functions follows:

provided by such systems as auxiliary building cooling water, service water, or component Permanently installed plant cooling water cooling when ac power is lost equipment used to support FLEX during the ELAP for Phase 1 and 2. For strategies do not require cooling example, the potential need for cooling water support systems, such as for the TDAFW pump bearings was not component cooling water and discussed. Additional analysis by the licensee service water, to perform their is required to determine the acceptability of the required functions. Therefore, no licensee's plans to provide supplemental additional analysis is required to cooling to the subject components when confirm the acceptability of normal cooling will not be available during the supplemental cooling to plant ELAP. equipment supporting Phase 1 or 2 strategies.

(Reference 17)

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 11 of 29 6.3. Confirmatory Items from Interim Staff Evaluation The following table provides a summary of the Confirmatory Items (CI) from the MPS2 Interim Staff Evaluation (ISE) and the status of each item.

Interim Staff Evaluation Confirmatory Items CI # Description Status 3.1.1.2.A Confirm that the preferred travel pathways are This ISE Cl is being addressed determined using the guidance contained in through the ongoing NRC audit NEI 12-06. The pathways will attempt to avoid process.

areas with trees, power lines, and other (References 17 and 19) potential obstructions and will consider the potential for soil liquefaction. This is scheduled to be completed in June 2014.

3.1.1.3,A Confirm that a review is completed to During the July 2014 NRC Onsite determine impacts from large internal flooding Audit, the NRC Staff indicated that sources that are not seismically robust and do further review of this item was not not require ac power. anticipated as DNC proceeds towards compliance for Orders EA-12-049 and EA-12-051.

(References 17 and 19) 3.1.1.4,A The licensee's plan for implementing the use This ISE Cl is being addressed of off-site resources is not complete. The through the ongoing NRC audit local assembly areas have not been identified. process.

The licensee is also evaluating the possibility (References 17 and 19) of boat transport for personnel.

3.1.2.2,A The licensee has identified open items related During the July 2014 NRC Onsite to deployment of equipment during flooding Audit, the NRC Staff indicated that conditions resulting from a hurricane, to verify further review of this item was not response times listed in the timeline and anticipated as DNC proceeds perform staffing assessment, and to perform towards compliance for Orders an evaluation of all BDB equipment fuel EA-12-049 and EA-12-051.

consumption and required re-fill strategies, (References 17 and 19) and to determine preferred travel pathways using the guidance contained in NEI 12- 06.

The pathways will attempt to avoid areas with trees, power lines, and other potential obstructions.

3.2.1.A Confirm that Combustion Engineering Case During the July 2014 NRC Onsite 21 in WCAP-1 7601 -P, as evaluated in MPS2 Audit, the NRC Staff indicated that document ETE-NAF-2012-0150, Section 6.1, further review of this item was not is representative for MPS2 and appropriate for anticipated as DNC proceeds simulating the ELAP transient. towards compliance for Orders EA-12-049 and EA-12-051.

(References 19 and 22)

Serial No.14-393 Docket No. 50-336 Order EA-1 2-049 Attachment 1 Page 12 of 29 Interim Staff Evaluation Confirmatory Items CI # Description Status 3.2.1.1.A Confirm that Westinghouse letter LTR-TDA- During the July 2014 NRC Onsite 13-31, Rev. 0-B, Attachment 1, shows that the Audit, the NRC Staff indicated that CENTS code used in the ELAP analysis for further review of this item was not Combustion Engineering (CE) plants is limited anticipated as DNC proceeds to analyzing the flow conditions before reflux towards compliance for Orders boiling initiates. This review should confirm EA-12-049 and EA-12-051.

an acceptable definition for the initiation of reflux boiling. (Generic)

_________(Reference 19) 3.2.1.2.A The RCP seal initial maximum leakage rate This ISE Cl is being addressed should be greater than or equal to the upper through the ongoing NRC audit bound expectation for the seal leakage rate process.

for the ELAP event discussed in the PWROG position paper addressing the RCP seal (Generic) leakage for CE plants (ADAMS Accession No. (References 19 and 23)

ML13235A151 (Non-Publicly Available)) or justification should be provided for use of a lower value.

3.2.1.6.A Sequence of Event (SOE) action Item 5 This ISE Cl is being addressed indicates that the ELAP is declared at 45 through the ongoing NRC audit minutes, and Action Item 6 indicates that at 50 process.

minutes (5 minutes after the declaration of the (References 4, 17, and 19)

ELAP), the operator controls SG atmospheric dump valves (ADVs) and AFW flow locally as an on-going action for cooldown and decay heat removal. On page 105 of the integrated plan in Attachment 1B NSSS Significant Reference Analysis Deviation Table, the licensee notes in item 6 that cooldown starts at 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> at 75 degrees F/hr. to a SG pressure of 135 psia. Clarification is needed to correct this apparent inconsistency.

3.2.1.6.B The licensee did not provide a discussion This ISE Cl is being addressed regarding the operator actions required to through the ongoing NRC audit control SG ADVs and AFW flow and process.

justification is needed to determine that all the (References 4, 17, and 19) required operator actions are reasonably achievable within the required time constraint of 50 minutes during the ELAP conditions, or a discussion regarding the required cooldown completion time that is supportable by analysis.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 13 of 29 Interim Staff Evaluation Confirmatory Items Cl # Description Status 3.2.1.6.C Confirm that response times listed in the SOE During the July 2014 NRC Onsite timeline are verified and that staffing Audit, the NRC Staff indicated that assessment has been performed. further review of this item was not anticipated as DNC proceeds towards compliance for Orders EA-12-049 and EA-12-051.

(Reference 24) 3.2.2.A Following a BDB event, a vent pathway would During the July 2014 NRC Onsite be required in the event of SFP bulk boiling Audit, the NRC Staff indicated that and can be established by opening the Fuel further review of this item was not Building roll-up doors for inlet and outlet air anticipated as DNC proceeds flow. However the licensee's strategy for towards compliance for Orders providing air flow to remove steam generated EA-12-049 and EA-12-051.

from pool boiling is not clear. The path for (References 17 and 19) inlet and exhaust air is apparently the same i.e., the fuel building rollup doors. It is not clear from the discussion provided how this will enable a flow path to vent the steam and condensate from the Fuel Building.

3.2.3.A During the audit process the licensee stated that This ISE Cl is being addressed the details of the long term Containment through the ongoing NRC audit cooldown and depressurization strategies for process.

MPS2 are still under development. Upon selection of the preferred strategy, detailed (See Section 4d and Reference 19)

GOTHIC analysis will be performed to document and validate the strategy and also to provide operators with timelines and guidelines for actions to ensure the long term integrity of the Containment throughout the Phase 3 of the postulated ELAP/LUHS scenario. Confirm that the revised analyses and the selected strategy are acceptable.

3.2.4.2.A The ventilation evaluation will be completed During the July 2014 NRC Onsite later this year and the results will be provided in Audit, the NRC Staff indicated that the February 2014 6-Month update. Confirm further review of this item was not that the evaluation and results are acceptable. anticipated as DNC proceeds towards compliance for Orders EA-12-049 and EA-12-051.

(See Attachment 2)

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 14 of 29 Interim Staff Evaluation Confirmatory Items Cl # Description Status 3.2.4.4.A Confirm the adequacy of existing lighting and During the July 2014 NRC Onsite the adequacy of portable lighting to perform Audit, the NRC Staff indicated that FLEX strategy actions. further review of this item was not anticipated as DNC proceeds towards compliance for Orders EA-12-049 and EA-12-051.

(References 17 and 19) 3.2.4.4.B Confirm that upgrades to the site's This ISE CI is being addressed communications systems have been completed. through the ongoing NRC audit process. (Reference 9) 3.2.4.6.A Additional information is needed to confirm This ISE Cl is being addressed habitability of the Main Control Room during the through the ongoing NRC audit ELAP. process. (References 17 and 19) 3.2.4.7.A Westinghouse is currently performing an During the July 2014 NRC Onsite analysis to determine the consequences of Audit, the NRC Staff indicated that usage of impure water sources in the steam further review of this item was not generators. The results of the analysis are anticipated as DNC proceeds expected to provide the allowed time limits on towards compliance for Orders usage of these sources. The NSRC will provide EA-12-049 and EA-12-051.

equipment to initiate residual heat removal and (See Section 4b and Reference 17) water treatment equipment such that heat removal can be ensured for extended durations.

Confirm that the analysis results and resultant strategies are acceptable.

3.2.4.9.A A secondary source for fuel oil will be the MPS3 During the July 2014 NRC Onsite Diesel Fuel Oil Storage Tanks. These Audit, the NRC Staff indicated that underground tanks contain a minimum of further review of this item was not 32,670 gallons of fuel oil. They are seismic and anticipated as DNC proceeds missile protected. Confirm the ability to transfer towards compliance for Orders this fuel, and complete an evaluation of all BDB EA-12-049 and EA-12-051.

equipment fuel consumption and required re-fill (References 17 and 19) strategies, including any gasoline required for small miscellaneous equipment.

3.2.4.1 0.A The licensee has completed an analysis of the During the July 2014 NRC Onsite battery capability regarding expected time Audit, the NRC Staff indicated that available with ac power. Site specific further review of this item was not procedural guidance governing load stripping anticipated as DNC proceeds will be developed. Confirm electrical towards compliance for Orders components performance requirements and EA-1 2-049 and EA-1 2-051.

electrical loading-related strategy objectives can (Reference 11) be met.

_____________________________________________________________________ .1.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 15 of 29 Interim Staff Evaluation Confirmatory Items Cl # Description Status 3.4.A The licensee's plans for the use of off-site This ISE Cl is being addressed resources conform to the minimum capabilities through the ongoing NRC audit specified in NEI12-06 Section 12.2, with regard process.

to the capability to obtain equipment and (Reference 19) commodities to sustain and backup the site's coping strategies (item 1). Confirm the licensee addresses the remaining items (2 through 10),

or provides an appropriate alternative.

6.4. Audit Questions Reviewed During the MPS2 NRC Onsite Audit Various MPS2 Audit Questions (AQs) were evaluated during the MPS Unit 2 NRC Onsite Audit.

The following AQs were evaluated and remain "Open".

I *1 Audit NEI 12-06 Section 5.3.2 Consideration 1 specifies that This AQ is being Question equipment deployment routes to be traveled should be addressed through the

1. 1 reviewed for potential soil liquefaction that could impede ongoing NRC audit equipment movement following a severe seismic event. process.

(References 17 and 19)

Dominion did not provide a definite conclusion regarding the potential for liquefaction along deployment routes or if liquefaction was an issue at MPS2. Dominion identified that liquefaction may be a problem but no analysis was provided to evaluate this potential deployment issue. Provide a discussion regarding the potential for seismic event liquefaction that clearly defines this deployment hazard for MPS2.

(Reference Item 3.1.1.2.A)

________ .1.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 16 of 29 Audit NEI 12-06 Section 5.3.3 Consideration 1 specifies that This AQ is being Question seismically qualified electrical equipment can be affected by addressed through the

1. 2 beyond-design-basis seismic events; therefore, guidance ongoing NRC audit should be available for determining instrument reading for process.

both main control room (MCR) and non-control room (References 19 and 25) readouts regarding how and where to measure key instrument readings at containment penetrations for example, where applicable, using a portable instrument.

Dominion's integrated plan did not include providing guidance for this situation. Provide a discussion of how plant staff will determine required key instrument readings if MCR instrumentation is not functioning following a seismic event.

(Reference Item 3.1.1.3.A)

J 4 Audit NEI 12-06, Section 9.3.3 requires providing procedural This AQ is being Question enhancements that involve addressing the effects of high addressed through the

1. 9 temperatures on the portable equipment. Dominion did not ongoing NRC audit provide any information regarding operation of portable process.

equipment at the high temperatures that may be (See Attachment 2) experienced due to the ELAP, i.e., would the equipment have to operate in any high temperature areas of the plant when deployed. A review of the diagrams provided in Figures 1-8 of the integrated plan appear to show that all portable FLEX equipment, (BDB pumps and ac generators) will be set up in areas outside of the buildings where the connections will be made. This would allow operation only in the high ambient temperatures external to plant buildings.

Dominion plans on storing BDB equipment so that it will be protected from high temperature events while stored in the BDB Storage Building(s) or in protected areas of the plant.

However, as noted on page 27 of the integrated plan, Dominion plans on locating the BDB AFW pump inside the Turbine Building for the specific case of imminent flooding for the installed TDAFW pump. In this situation the portable pump would be operating inside a confined space, subject to high temperatures due to lack of ventilation. Provide a discussion regarding the ability of FLEX equipment to operate at potentially high ambient temperatures for placement of portable FLEX equipment in the situation where the portable BDB AFW pump is operated inside the Turbine Building. (Reference Item 3.1.5.3.A)

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 17 of 29 Audit NEI 12-06, Section 3.2.2, Paragraph (5) provides that: plant This AQ is being Question procedures/guidance should ensure that a flow path is addressed through the

1. 10 promptly established for makeup flow to the steam ongoing NRC audit generator/nuclear boiler and identify backup water sources process.

in order of intended use. Additionally, plant (References 17 and 19) procedures/guidance should specify clear criteria for transferring to the next preferred source of water. Dominion did provide supporting information regarding the analyses used to determine: (1) the required time of 1.8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> to control the AFW flow for SG overfill prevention, and (2) the required CST- Long Island Sound switchover time of no greater than 8.4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, and did not address the adequacy of the analyses including the computer codes/methods and assumptions used. For example, it was not clear if the decay heat model was based on ANS 5.1-1979 + 2 sigma model. Discuss the analysis that was used to determine the timing of switchover from CST to the UHS water supplies for SG makeup, and address the adequacy of the analysis, computer codes/methods, and assumptions used in the analysis. Also, discuss and justify the decay heat model used in this analysis.

(Reference Item 3.2.1.A)

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 18 of 29 Audit NEI 12-06, Section 3.2.2, Paragraph (5) provides that: plant This AQ is being Question procedures/guidance should ensure that a flow path is addressed through the

1. 36 promptly established for makeup flow to the steam ongoing NRC audit generator/nuclear boiler and identify backup water sources process.

in order of intended use. This section also specifies that (See Section 4b and when all other preferred water sources have been depleted, References 17 and 19) lower water quality sources may be pumped as makeup flow using available equipment and that procedures/guidance should clearly specify the conditions when the operator is expected to resort to increasingly impure water sources. Dominion noted for the alternate strategy for RCS makeup, that water would be added to a batching tank and that "Bags of powdered boric acid are easy to deploy to any area of the plant where the batching tanks are required. Water for mixing would be supplied by the BDB High Capacity pump." The water supplies in this instance would be water from either a 3 million gallon site pond or the UHS. Both of these makeup water supplies could potentially contain debris or foreign material. Provide a discussion and analysis of the possible consequences of injecting potentially impure or contaminated water from the UHS or the site 3 million gallon pond into the RCS or the SG's. (Reference Item 3.2.4.5.B)

Audit Section 3.2 of WCAP-17601-P discusses the PWROG's This AQ is being Question recommendations that cover the following subjects for addressed through the

1. 44 consideration in developing FLEX mitigation strategies: (1) ongoing NRC audit minimizing RCP seal leakage rates; (2) adequate shutdown process.

margin; (3) time initiating cooldown and depressurization; (References 17 and 19)

(4) prevention of the RCS overfill; (5) blind feeding an SG with a portable pump; (6) nitrogen injection from SITs; and (7) asymmetric natural circulation cooldown (NCC). Discuss Dominion's position on each of the recommendations discussed above for developing the FLEX mitigation strategies. List the recommendations that are applicable to the plant, provide rationale for the applicability, address how the applicable recommendations are considered in the ELAP analysis, and discuss the plan to implement the recommendations. Also, provide rationale for each of the recommendations that are determined to be not applicable to the plant.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 19 of 29 Audit Reference Item 3.2.1.8.C. Section C.2 describes that if This AQ is being Question venting of the RCS is necessary, the operators will use the addressed through the

1. 58 remotely-operated reactor head vents. This information ongoing NRC audit does not provide reasonable assurance that the plan process.

conforms to the guidance of NEI 12-06, Section 3.2.2, (References 17 and 19)

Paragraph (3), since this section does not describe how these head vents are going to be operated (i.e., will portable battery packs be used to open and/or close the head vents?). Please provide information about operation of the head vents and if power will be necessary for their operation.

6.5. Additional Items Reviewed During the MPS2 NRC Onsite Audit The following table provides a list of the additional Safety Evaluation (SE) Review items identified and evaluated during the MPS2 NRC Onsite Audit and the status of each item.

Safety WCAP-17792-P - Provide a detailed discussion on the During the July 2014 NRC Evaluation applicability to MPS2 of the recommendations in Onsite Audit, the NRC Staff Review WCAP-17792 to vent the RCS while makeup is being indicated that further Item #1 provided for the mitigating strategies involving RCS review of this item was not makeup and boration. This discussion should include if anticipated as DNC the MPS2 strategy includes venting the RCS, methods proceeds towards of venting, vent operations criteria, related fluid dynamic compliance for Orders EA-analysis, involving instrumentation, and related 12-049 and EA-12-051.

parameter thresholds. (References 17 and 19)

Safety Time to reflux cooling - Please clarify whether the During the July 2014 NRC Evaluation intended timeline for aligning the FLEX RCS makeup Onsite Audit, the NRC Staff Review pump may be delayed based on procedural guidance indicated that further Item #3 that derives from the analysis in WCAP-1 7792-P, pages review of this item was not 3-10 through 3-16. Although the staff recognizes that anticipated as DNC plant operators require leeway to control pumps and proceeds towards equipment in response to plant indications and other compliance for Orders EA-symptoms, the staff considers it prudent that equipment 12-049 and EA-12-051.

alignments proceed as outlined in the integrated plan to (References 19 and 23) the extent possible. Therefore, provide justification if the operators would delay the alignment of the FLEX RCS makeup pump(s) beyond the time specified in the integrated plan based on initial indications that the reactor coolant pump seal leakage is lower than the value assumed in the ELAP analysis.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 20 of 29 Safety Human factors questions addressed during walkdowns This SE Review Item is Evaluation of plant equipment as well as in discussion with being addressed through Review personnel. the ongoing NRC audit Item #4 process. (Reference 19)

Safety Please provide adequate basis that, when considering During the July 2014 NRC Evaluation mixing time, there is sufficient flow capacity to support Onsite Audit, the NRC Staff Review borated makeup to both units from a single RCS indicated that further Item #5 makeup pump taking suction from a portable batching review of this item was not tank. anticipated as DNC proceeds towards compliance for Orders EA-12-049 and EA-12-051.

(Reference 19)

Safety EMC Compliance During the July 2014 NRC Evaluation Onsite Audit, the NRC Staff Review indicated that further Item #6 review of this item was not anticipated as DNC proceeds towards compliance for Orders EA-12-049 and EA-12-051.

(Reference 19)

Safety Provide evaluation for the cross-tie of the Unit 2 During the July 2014 NRC Evaluation batteries 201A and 201 B. Onsite Audit, the NRC Staff Review indicated that further Item #7 review of this item was not anticipated as DNC proceeds towards compliance for Orders EA-12-049 and EA-12-051.

(Reference 19)

Safety Evaluate vendor information for the C&D batteries (Unit This SE Review Item is Evaluation 2) for operation beyond an 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> duty cycle, being addressed through Review the ongoing NRC audit Item #8 process. (Reference 19)

Safety Security Related Issues. This SE Review Item is Evaluation being addressed through Review the ongoing NRC audit Item #9 process. (Reference 19) 7 Potential Safety Evaluation Impacts Section 6.5 provides a list of the additional Safety Evaluation (SE) Review items identified and evaluated during the MPS NRC Onsite Audit and the status of each item.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 21 of 29 Additionally, DNC is participating in the ongoing industry effort to develop guidance for the Final Integrated Plan that will support NRC preparation of the Safety Evaluation documenting MPS2 compliance with Order EA-12-049. The format of the Final Integrated Plan is consistent with the Safety Evaluation Template provided with the July 1, 2014 Jack Davis memorandum (ML14161A643)(Reference 18).

8 Supplemental Information This supplemental information provides details of the changes identified in the status updates above and addresses the following topics: a) a revision to Milestone Task 'Develop Modifications,' b) a revision to Milestone Task 'Implement Modifications,' c) a revision to Milestone Task 'Implement Training,' d) a revision to Milestone Task 'Issue FSGs and Associated Procedure Revisions,' e) a revision to Milestone Task 'Receive Equipment,' f) a revision to Milestone Task 'Create Maintenance Procedures,' g) a revision to Open Item No. 5, and, h) a revision to Open Item No.21.

a) MPS2, Milestone Task 'Develop Modifications': The revision to the scheduled target completion date is needed to obtain final design change approval of the MPS2 modifications to the Atmospheric Dump Valve (ADV) outlet piping supports.

b) MPS2, Milestone Task 'Implement Modifications': The revision to the scheduled milestone target completion date is required since the ADV modification requires a unit outage. This revised date is consistent with the date for full implementation of the FLEX Mitigating Strategies for MPS2.

c) MPS2, Milestone Task 'Implement Training': The revision to the scheduled milestone target completion date corresponds to the training completion date set for MPS3, since MPS2 and MPS3 BDB training is performed jointly. The MPS3 date is the result of a relaxation of Condition A.2 of the Order requested by DNC and accepted by the NRC.

The revised target completion date meets the schedule for full implementation of the FLEX Mitigating Strategies for MPS2.

d) MPS2, Milestone Task 'Issue FSGs and Associated Procedure Revisions': The revision to the scheduled milestone target completion date allows for completion of the MPS2 FSGs in line with the schedule for validation and training on the FSGs.

e) MPS2, Milestone Task 'Receive Equipment': The majority of the purchased major equipment has been received onsite. However, delivery of the final items has been delayed and is not expected until September 2014.

f) MPS2, Milestone Task 'Create Maintenance Procedures': The Milestone is to be restated as 'Develop Maintenance Strategies." This change is to revise the current milestone to reflect the intended activity which was to develop the maintenance strategies based on industry and vendor supplied information. As per the response provided above for Open Item 6, the restated task has been completed. The design change implementing the FLEX Mitigating Strategies Program identifies the

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 22 of 29 maintenance strategies required for the FLEX implementation and requires that Periodic Maintenance (PM) procedures be developed. Submittal of requests for creation of these PMs is in accordance with the Design Control Program and will be tracked. The PMs will be prioritized such that the near-term requirements, (e.g., 30 day walkdown inspections) are in-place prior to FLEX Mitigating Strategy implementation date. The PMs for the longer term requirements will be implemented prior to their first performance interval.

g) MPS2, Open Item 5: The Open Item completion date is revised to July 2015. The revision to the scheduled Milestone target completion date allows for completion of the MPS2 FSGs in line with the schedule for validation and training on the FSGs.

h) MPS2, Open Item 21: The majority of the purchased major equipment has been received onsite. However, delivery of the final items has been delayed and is not expected until September 2014.

9 References The following references support the updates to the Overall Integrated Plan described in this attachment and are available in ADAMS or have been provided to the staff for their review.

1. DNC'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 (Serial No. 12-161B).

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. NEI 12-06, "Diverse and Flexible Coping Strategies (FLEX) Implementation Guide,"

Revision 0, dated August 2012.

4. DNC's Supplement to Overall Integrated Plan in Response to March 21, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis Events (Order Number EA-12-049), dated April 30, 2013 (Serial No. 12-161C).

5. Calculation 13-024, "Turbine Driven Auxiliary Feedwater (TDAFW) Pump Delivered Flow at Reduced Steam Generator Pressure," April 22, 2013.

6. Engineering Technical Evaluation ETE-MP-2013-1034, "MP2 Turbine Driven Aux Feedwater Pump Minimum Continuous Operating Speed," dated March 12, 2013.

7. PWROG letter, OG-13-197, Transmittal of PA-PSC-0965 Final CE-NSSS Specific ELAP Response (FLEX) Guidelines, May 17, 2013.

8. Calculation 13-015, "MP2 & MP3 FLEX Strategy Hydraulic Calculations," Rev. 0.

9. ETE-CPR-2013-0003, "Beyond Design Basis Communications Strategy/Plan," Rev. 1.

10. Calculation 13-015, "MP2 & MP3 FLEX Strategy Hydraulic Calculations," Rev. 2.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 23 of 29

11. Calculation 2013-ENG-04383E2, "Millstone Power Station Unit 2 Beyond Design Basis -

FLEX Electrical 4160V, 4840V and 120VAC System Loading Analysis," Rev. 0.

12. URS Geotechnical Investigation and Engineering Report, FLEX Storage Building Project, Millstone Power Station, Waterford, Connecticut, dated January 27, 2014.

13.Design Change MPG-13-00010, "BDB Storage Building/Millstone Power Station/Units 2&3."

14.DNC's 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 Number EA-12-049), dated August 23, 2013 (Serial No. 12-161D).

15. Millstone Power Station, Units 2 and 3 - Interim Staff Evaluation Relating to Overall Integrated Plan in Response to Order EA-12-049 (Mitigating Strategies), dated January 31, 2014.

16. DNC's 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 Number EA-12-049), dated February 28, 2014 (Serial No. 12-161E).

17.ETE-CPR-12-0008, Rev. 3 "Beyond Design Basis - FLEX Strategy Overall Integrated Plan Basis Document."

18. Memorandum from Jack R. Davis, JLD, Office of NRR, to Stewart N. Bailey, Sheena A, Whaley, and Jeremy S. Bowen, "Supplemental Staff Guidance for the Safety Evaluations for Order EA-12-049 on Mitigation Strategies for Beyond-Design-Basis External Events and Order EA-12-051 on Spent Fuel Pool Instrumentation," dated July 1, 2014 (ML14161A643).

19. NRC letter from Jack R. Davis, Director Mitigating Strategies Directorate to All Operating Reactor Licensees and Holders of Construction Permits, "Nuclear Regulatory Commission Audits of Licensee Responses to Mitigating Strategies Order EA-12-049,"

dated August 28, 2013 (ML13234A503)

20. Procedure CM-AA-BDB-102, "Beyond Design Basis FLEX Equipment Unavailability Tracking."

21. Procedure CM-AA-BDB-1 0, "Beyond Design Basis FLEX Program."

22. Zachary Engineering Evaluation EE 13-E02, Evaluation of Atmospheric Dump Valve (ADV) Pipe for Tornado Generated Missile - Millstone Unit 2, Rev. 0

23. ETE-CPR-2012-0150, Rev. 1, Add. 0, "Core Cooling Evaluation for Dominion Fleet and Prepared Input for Response to Order EA-12-049."

24. DNC's March 12, 2012 Information Request, Phase 2 Staffing Assessment Report, dated June 12, 2014 (Serial No.14-198).

25. FSG-7, "Loss of Vital Instrumentation or Control Power."

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 24 of 29 Table 1 - PWR Portable Equipment Phase 21 Use and (Potential I Flexibility) Diverse Uses Performance Maintenance Criteria Maintenance!

List Portable Preventive Equipment Core Containment SFP Instrumentation Accessibility Maintenance Requirements BDB High Capacity Will follow EPRI diesel-driven pump (2) X X X 1200 gpm @ template and assoc. hoses and 150 psid templte fittings requirements BDB AFW pump (3) and 300 gpm @ Will follow EPRI assoc. hoses and X 500 psid template fittings requirements BDB RCS Injection Will follow EPRI pump (2) and assoc. 45 gpm @ Wilate hoses and fittings X 3000 psid template requirements 120/240VAC generators Will follow EPRI (3) and associated X 23.3 kW template cables, connectors and requirements switchgear

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 25 of 29 Table 1 - PWR Portable Equipment Phase 21 Use and (Potential I Flexibility) Diverse Uses Performance Maintenance Criteria Maintenance/

List Portable Preventive Equipment Core Containment SFP Instrumentation Accessibility Maintenance Requirements 120/240VAC generators (8)2 and associated Will follow EPRI cables, connectors and X 5-6.5 kW template switchgear (to power requirements support equipment) 480VAC generators (3) and associated cables, connectors and Will follow EPRI switchgear (to re-power X X X 500 kW template requirements battery chargers, inverters, and Vital Buses)

Portable boric acid gal Will follow EPRI batching tank (2) template requirements Will follow EPRI Light plants (2) X template requirements

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 26 of 29 Table 1 - PWR Portable Equipment Phase 21 Use and (Potential I Flexibility) Diverse Uses Performance Maintenance Criteria Maintenance/

List Portable Preventive Equipment Core Containment SFP Instrumentation Accessibility Maintenance Requirements Front end loader (1)2 X Will followrequirements template EPRI Tow vehicles (2) 2 X X X X Will follow EPRI template requirements Hose trailer (2) and Will follow EPRI Utility vehicle (1)2 X X X X template requirements Fans / blowers (10)2 X Will followrequirements template EPRI Air compressors (6)2 X X Will followrequirements template EPRI Fuel truck (1) with 1,100 X X X X X Will follow EPRI gal. tank and pumps template requirements Fuel carts with transfer Will follow EPRI pumps (2) 2 X X X X X template requirements Communications Will follow EPRI equipment 3 X X X X X template requirements

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 27 of 29 Table 1 - PWR Portable Equipment Phase 21 Use and (Potential I Flexibility) Diverse Uses Performance Maintenance Criteria Maintenance/

List Portable Preventive Equipment Core Containment SFP Instrumentation Accessibility Maintenance Requirements Misc. debris removal Will follow EPRI equipment 2 X template requirements Misc. Support Will follow EPRI Equipment 2 template requirements NOTES:

1. This table is based on one BDB Storage Building containing equipment for both MPS2 and MPS3.

2. Support equipment. Not required to meet N+1.

3. Quantities are identified in ETE-CPR-2013-0003 that was developed in response to the results of the communications study performed for Recommendation 9.3 of the 10 CFR 50.54(f) letter dated March 12, 2012.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 28 of 29 Table 2 - PWR Portable Equipment Phase 3 Use and (Potential / Flexibility) Diverse Uses Performance Criteria Maintenance Notes List Portable Quantity Quantity Power Core Cont. Access Instrumentation RCS Preventative Equipment Req'd Provided Cooling Cooling/ Inventory Maintenance

/Unit IUnit Integrity Required Medium Jet Performedby Voltage 2 2 Turb. X X X 4.16 KV 1 MW NSRC (1)

Generators Low Voltage 0 Jet X X X 480VAC 1100 KW Performedby (2)

Generators Turb. NSRC H ig h .. .

Pressure Performed by Diesel X 3000# 60 GPM NSRC (2)

Injection PumpI S/G RPV Makeup 0 1 Diesel X X 500# 500 GPM NSRC by Performed (2 (2)

Pump Low Presue/Perform ed by Pressure 0 1 Diesel X 300# 2500 GPM Medium NSrC NSRC (2)

Flow Pump Low Pressure 1 Diesel X X 150# 5000 GPM Performed by High Flow NSRC (3)

Pump Lighting Diesel X.40,000.Lu.Performed by 0 1 *  : 40,000 Lu NSRC (4)

Towers

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 1 Page 29 of 29 Table 2 - PWR Portable Equipment Phase 3 Use and (Potential I Flexibility) Diverse Uses Performance Criteria Maintenance Notes List Portable Quantity Quantity Power Core Cont. Access Instrumentation RCS Preventative Equipment Req'd Provided Cooling Cooling/ Inventory Maintenance

/Unit I Unit Integrity Required Diesel Fuel 0 AR N/A X 500 Gal Performed by (2)

Transfer NSRC Mobile Performedby Water 0 2 Diesel X X 150 GPM NSRC (2)f(5)

Treatment Mobile Boration 0 N/A X 1000 Gal Performed (2)

Skid NSRC Note 1 - NSRC 4KV generator supplied in support of Phase 3 for Core Cooling, Containment Cooling, and Instrumentation FLEX Strategies. (Includes a distribution panel and sufficient cables for connection to site 4kV buses.)

Note 2 - NSRC Generic Equipment - Not required for FLEX Strategy - Provided as Defense-in-Depth.

Note 3 - NSRC Low Pressure / High Flow pump supplied in support of Phase 3 for Core Cooling and Containment Cooling FLEX Strategies.

Note 4 - NSRC components provided for low light response plans.

Note 5 - Usage dependent on Westinghouse Water Quality Study results.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 2 Overall Integrated Plan Section F5 Safety Function Support (Ventilation)

Millstone Power Station Unit 2 Dominion Nuclear Connecticut, Inc. (DNC)

Serial No.14-393 Docket Nos. 50-336 Order EA-12-049 Attachment 2 Page 1 of 8 F5 - Safety Functions Support (Ventilation)

Determine Baseline coping capability with installed coping 1 modifications not including FLEX modifications.

F5.1 - PWR Installed Equipment Phase I Provide a general description of the coping strategies using installed equipment including station modifications that are proposed to maintain and/or support safety functions.

Identify methods and strategy(ies) utilized to achieve coping times.

The FLEX strategies for maintenance and/or support of safety functions involve several elements. One element is to ensure that ventilation, heating, and cooling are adequate to maintain acceptable environmental conditions for equipment operation and personnel habitability. Per the guidance given in NEI 12-06, FLEX strategies must be capable of execution under the adverse conditions (unavailability of installed plant lighting, ventilation, etc.) expected following a BDB External Event (BDBEE) resulting in an Extended Loss of AC Power/Loss of Ultimate Heat Sink (ELAP/LUHS). The primary concern with regard to ventilation is the heat buildup which occurs with the loss of forced ventilation in areas that continue to have heat loads.

The key areas identified for all phases of implementation of the FLEX Mitigating Strategy activities are the Main Control Room (MCR), East & West DC Switchgear (SWGR)

Rooms, Enclosure Building - East & West Penetration Rooms (location of the Atmospheric Dump Valves, ADVs), East 480V Load Center, TDAFW Pump Room, Upper 4kV SWGR Room, MCC B61 Enclosure, Charging Pump Cubicles, the Control Room A/C (CRAC)/Mechanical Equipment Room (MER), and the Track Bay area of the Turbine Building. These areas have been evaluated to determine the temperature profiles following an ELAP/LUHS event. With the exception of the TDAFW Pump Room, the Upper 4kV SWGR Room and the Charging Pump Cubicle, results of the evaluations have concluded that for all other identified areas, some actions are needed (either short term or long term actions) in order for temperatures to remain within acceptable limits following a BDBEE. The evaluations are based on conservative input heat load assumptions for all areas and with preemptive actions being taken, only when necessary, to reduce heat load or to establish either active or passive ventilation (e.g., portable fans, open doors, etc.)

The Phase 1 actions for ventilation are actions involving existing plant structures, primarily doors, and constitute the short term actions required. The Phase 1/short term 1 Coping modifications consist of modifications installed to increase initial coping time, i.e.,

generators to preserve vital instruments or increase operating time on battery powered equipment.

Serial No.14-393 Docket Nos. 50-336 Order EA-12-049 Attachment 2 Page 2 of 8 actions for the MCR are those required by existing procedures for Station Blackout (SBO) and require certain instrument cabinets to be opened within 30 minutes. The Phase 1 actions for the DC SWGR Rooms (which include the station battery rooms), East 480V Load Center, and MCC 61 Enclosure are to open various designated doors within 30 minutes, 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, and 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, respectively. No Phase 1 actions are required for the CRAC/MER or areas inside the Turbine Building.

The Enclosure Building East and West Penetration Rooms do not require supplemental ventilation, either passive or active. However, since an operator must pass through the Spent Fuel Pool (SFP) area to get to the east penetration room to operate the ADVs, the actions to open up the several designated doors in the SFP area is considered a Phase 1 action.

Details:

F5.1.1 - Provide a brief Confirm that procedure/guidanceexists or will be developed to description of support implementation.

Procedures /

Strategies / Guidelines The Unit 2 Station Blackout Procedure (AOP 2530) directs the actions to be taken within the MCR.

The FLEX Strategy Guideline FSG-5 will include the actions to open the various designated doors to allow for natural circulation of air where necessary. This action alone will ensure that the temperatures in the affected rooms remain acceptable.

No other actions are required to maintain equipment operation or personnel habitability following an ELAP/LUHS event in Phase 1.

F5.1.2 - Identify List modifications and describe how they support coping time.

modifications No ventilation related modifications are required for any phase of the ELAP/LUHS response.

F5.1.3 - Key List instrumentationcredited for this coping evaluation phase.

Parameters No key ventilation parameters have been identified as required to maintain acceptable equipment and personnel environments for any phase of the ELAP/LUHS response.

Notes:

The information provided in this section is based on the following reference(s):

- Beyond Design Basis - FLEX Strategy Overall Integrated Plan Basis Document, ETE-CPR-

Serial No.14-393 Docket Nos. 50-336 Order EA-12-049 Attachment 2 Page 3 of 8 2012-0009, Rev. 3.

F5 - Safety Functions Support (Ventilation)

F5.2 - PWR Portable Equipment Phase 2 Provide a general description of the coping strategies using on-site portable equipment including station modifications that are proposed to maintain and/or support safety functions. Identify methods and strategy(ies) utilized to achieve coping times.

Per the guidance given in NEI 12-06, FLEX strategies must be capable of execution under the adverse conditions (unavailability of installed plant lighting, ventilation, etc.) expected following a BDBEE resulting in an ELAP/LUHS. The ventilation related actions that are taken in Phase 1 are expected to dissipate the minimal heat loads from the DC battery sources and residual heat loads in the de-energized equipment. However, Phase 2 introduces additional loads when the BDB 480 VAC diesel generator is placed into service.

The Phase 2 actions are adequate for the longer term ventilation needs. Primarily these actions involve the restoration of existing ventilation equipment using power supplied by the BDB 480 VAC generators. This includes the MCR HVAC system and the supply and exhaust fans in DC SWGR Rooms and 480V Load Center. Additionally, since the MCR HVAC is energized, the heat load in the CRAC/MER Room increases and supplemental cooling (by means of a fan in the open doorway to the 480V Load Center) is required to maintain acceptable temperatures.

The enclosure for MCC B61 has a dedicated HVAC unit. If a jumper cannot be used to repower the cooling unit, it is sufficient to open the enclosure door and blow air into the enclosure using one of the fans available in the miscellaneous BDB equipment.

An additional Phase 2 action may be required in the unlikely scenario that the diesel powered BDB AFW pump is required to operate while it is pre-staged inside the Turbine Building Track Bay. If this were to occur, the BDB procedure to operate the pump inside the Track Bay would require that the nearby rollup door (behind the closed flood gate) and a door on the 70' elevation be opened to allow air exchange in the area of the operating pump. This would be required coincident with the starting of the pump but would no longer be necessary after the flood gates are opened and the BDB AFW pump is re-located to its normally deployed location just outside of the Track Bay.

Details:

F5.2.1 - Provide a brief Confirm that procedure/guidanceexists or will be developed to description of support implementation with a description of the procedure /

Procedures I Strategies strategy/guideline.

I Guidelines

Serial No.14-393 Docket Nos. 50-336 Order EA-12-049 Attachment 2 Page 4 of 8 The FLEX Strategy Guideline, FSG-5, will include the actions to open the various designated doors to allow for natural circulation of air where necessary.

FSG-3 will open the necessary doors if the BDB AFW pump is operated inside the Turbine Building.

FSG-4 directs the restoration of installed ventilation and cooling systems when power is available.

F5.2.2 - Identify List modifications necessary for phase 2 modifications No ventilation related modifications are required for any phase of the ELAP/LUHS response.

F5.2.3 - Key Parameters List instrumentationcredited or recovered for this coping evaluation.

No key ventilation parameters have been identified as required to maintain acceptable equipment and personnel environments for any phase of the ELAP/LUHS response.

F5.2.4 - Storage I Protection of Equipment:

Describe storage / protection plan or schedule to determine storage requirements Seismic List how equipment is protected or schedule to protect All equipment necessary to implement the Unit 2 ventilation strategy is stored in areas that are protected against seismic hazards.

Flooding List how equipment is protected or schedule to protect All equipment necessary to implement the Unit 2 ventilation strategy is stored in areas that are above the maximum flood levels for the Millstone site.

Severe Storms with List how equipment is protected or schedule to protect High Winds All equipment necessary to implement the Unit 2 ventilation strategy is stored in areas that are protected from hurricanes, tornados, and strong winds.

Serial No.14-393 Docket Nos. 50-336 Order EA-12-049 Attachment 2 Page 5 of 8 Snow, Ice, and Extreme List how equipment is protected or schedule to protect Cold All equipment necessary to implement the Unit 2 ventilation strategy is stored in areas that are protected from extreme weather conditions.

High Temperatures List how equipment is protected or schedule to protect All equipment necessary to implement the Unit 2 ventilation strategy is stored in areas that are protected from extreme weather conditions.

F5.2.5 - Deployment Conceptual Design Strategy Modifications [Protection of connections

a. Identify Strategy Identify modifications Identify how the connection including how the is protected equipment will be deployed to the point of use. No ventilation related No ventilation related modifications are needed to connections are needed to There is a minimal support the implementation of support the implementation deployment of the ELAP/LUHS coping of the ELAP/LUHS coping supplemental ventilation strategies. strategies.

equipment in the ELAP/LUHS coping strategies. Most of the ventilation provided by the strategy is existing plant equipment that is repowered by the 480 VAC diesel generator.

In addition to opening doors, the strategy only identifies two areas where supplemental cooling, using portable fans, is required. These areas are: 1) the area between the CRAC/MER Room and the 480V Load Center and 2) the MCC B61 Enclosure.

Serial No.14-393 Docket Nos. 50-336 Order EA-12-049 Attachment 2 Page 6 of 8 Although no additional cooling measures, other than those identified above, are necessary, the operating staff will periodically monitor area temperatures to insure habitability and equipment survivability conditions are acceptable. Additional natural convection flow paths or portable ventilation fans and/or stand alone AC units may be utilized if the area temperature measurements indicate unacceptable increasing trends.

Notes:

The information provided in this section is based on the following reference(s):

- Beyond Design Basis - FLEX Strategy Overall Integrated Plan Basis Document, ETE-CPR-2012-0009, Rev. 3.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 2 Page 7 of 8 F5 - Safety Functions Support (Ventilation)

F5.3 - PWR Portable Equipment Phase 3 Provide a general description of the coping strategies using phase 3 equipment including modifications that are proposed to maintain and/orsupport safety functions. Identify methods and strategy(ies) utilized to achieve coping times.

Per the guidance given in NEI 12-06, FLEX strategies must be capable of execution under the adverse conditions (unavailability of installed plant lighting, ventilation, etc.) expected following a BDBEE resulting in an ELAP/LUHS. Any additional heat loads added as a result of Phase 3 repowering efforts utilizing the 4kV generator from the National SAFER Response Center (NSRC) are addressed by the existing ventilation systems repowered by either the BDB 480VAC diesel generator or the 4kV generator received from the NSRC.

Therefore, no Phase 3 actions are required to maintain equipment operation or personnel habitability.

Details:

F5.3.1 - Provide a brief Confirm that procedure/guidanceexists or will be developed to description of support implementation with a description of the procedure/

Procedures I Strategies strategy / guideline.

I Guidelines No procedures/strategies are required to maintain any Phase 3 equipment operation or personnel habitability following an ELAP/LUHS event.

F5.3.2 - Identify List modifications necessary for phase 3 modifications No ventilation related modifications are required for any phase of the ELAP/LUHS response.

F5.3.3 - Key Parameters List instrumentationcredited or recovered for this coping evaluation.

No key ventilation parameters have been identified as required to maintain acceptable equipment and personnel environments for any phase of the ELAP/LUHS response.

Serial No.14-393 Docket No. 50-336 Order EA-12-049 Attachment 2 Page 8 of 8 F5 - Safety Functions Support (Ventilation)

F5.3 - PWR Portable Equipment Phase 3 F5.3.4 - Deployment Conceptual Design Strategy I Modifications Protection of connections

a. Identify Strategy including Identify modifications Identify how the connection how the equipment will be is protected deployed to the point of use.

There is no required No ventilation related No ventilation related deployment of supplemental modifications are needed to connections are needed to ventilation equipment in the support the implementation support the implementation ELAP/LUHS coping of the ELAP/LUHS coping of the ELAP/LUHS coping strategies for Phase 3. strategies. strategies.

Although no additional compensatory cooling measures are expected to be necessary, for defense in depth, the operating staff will periodically monitor area temperatures to insure habitability and equipment survivability conditions are acceptable. Additional natural convection flow paths or portable ventilation fans and/or stand alone AC units may be utilized if the area temperature measurements indicate unacceptable increasing trends.

Notes:

The information provided in this section is based on the following reference(s):

- Beyond Design Basis - FLEX Strategy Overall Integrated Plan Basis Document, ETE-CPR-2012-0009, Rev. 3.