ML13247A288

First Six-Month Status Report in Response to the 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) for Watts Bar Nuclea

ML13247A288
Person / Time
Site:	Watts Bar
Issue date:	08/28/2013
From:	James Shea Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
DPPR-0092, EA-12-049
Download: ML13247A288 (10)

Text

Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402 August 28, 2013 10 CFR 2.202 10 CFR 50.4 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Watts Bar Nuclear Plant, Unit 1 Facility Operating License No. NPF-90 NRC Docket Nos. 50-390 Watts Bar Nuclear Plant, Unit 2 Construction Permit No. CPPR-92 NRC Docket No. 50-391

Subject:

First Six-Month Status Report in Response to the 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) for Watts Bar Nuclear Plant

References:

1. NRC Order Number EA-1 2-049, "Issuance of Order to Modify Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events," dated March 12, 2012 (ML12054A735)

2. NRC Interim Staff Guidance JLD-ISG-2012-01, "Compliance with Order EA 049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events,"

Revision 0, dated August 29, 2012 (ML12229A174)

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

Implementation Guide" Revision 0, dated August 2012 (ML12242A378)

4. Letter from TVA to NRC, "Tennessee Valley Authority (TVA) - Initial Status Report in Response to the 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 October 29, 2012 (ML12307A104)

Printed on recycled paper

U.S. Nuclear Regulatory Commission Page 2 August 28, 2013

5. Letter from TVA to NRC, "Tennessee Valley Authority (TVA) - Overall Integrated Plan in Response to the 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) for Watts Bar Nuclear Plant," dated February 28, 2013 (ML13067A030)

On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued an order (Reference

1) to Tennessee Valley Authority (TVA). Reference 1 was immediately effective and directs TVA to develop, implement, and maintain guidance and strategies to maintain or restore core cooling, containment, and spent fuel pool cooling capabilities following 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 Nuclear Energy Institute (NEI) 12-06, Revision 0 (Reference 3) with clarifications and exceptions identified in Reference 2. Reference 4 provided the TVA initial status report regarding mitigation strategies. Reference 5 provided the TVA Watts Bar Nuclear Plant, Units 1 and 2 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. The purpose of this letter is to provide the first 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 submittal of the overall integrated plan, including any changes to the compliance method or schedule.

The Enclosure describes the plans that TVA will use to meet the regulatory requirements outlined in Attachment 2 of Reference 1, but does not identify any additional actions to be taken by TVA. Therefore, this letter contains no regulatory commitments.

If you have any question regarding this submittal, please contact Kevin Casey at (423) 751-8523.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 28th day of August 2013.

Respec 11 J.

Viie P sident, Nuclear Licensing Enclosure cc: See Page 3

U.S. Nuclear Regulatory Commission Page 3 August 28, 2013

Enclosure:

Tennessee Valley Authority Watts Bar Nuclear Plant's First 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 cc (Enclosure):

NRR Director - NRC Headquarters NRO Director - NRC Headquarters NRC Regional Administrator - Region II NRC Project Manager - Watts Bar Nuclear Plant, Unit 1 NRC Project Manager - Watts Bar Nuclear Plant, Unit 2 NRC Senior Resident Inspector - Watts Bar Nuclear Plant

ENCLOSURE TENNESSEE VALLEY AUTHORITY WATTS BAR NUCLEAR PLANT'S FIRST 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

ENCLOSURE Introduction Tennessee Valley Authority developed an Overall Integrated Plan (Reference I in Section 8) for Watts Bar Nuclear Units 1 and 2, 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 or schedule.

2 Milestone Accomplishments The following milestone(s) have been completed since the development of the Overall Integrated Plan (Reference 1), and are current as of July 30, 2013.

• FLEX Strategy Evaluation - Complete

• Modifications Evaluations - Complete

" Unit 1 N-1 Walkdown - Complete

• Unit 2 Walkdown - Complete

• Procedures - PWROG issues NSSS-specific guidelines - Complete 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.

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~Q~hp~eAd, Activit Target Mn S,'tatu's Completion Submit 60 Day Status Report Oct 2012 Complete Submit Overall Integrated Plan Feb 2013 Complete Update 1 Aug 2013 Complete Update 2 Feb 2014 Not Started Update 3 Aug 2014 Not Started Update 4 Feb 2015 Not Started Update 5 Aug 2015 Not Started Update 6 Feb 2016 Not Started Update 7 Aug 2016 Not Started FLEX Strategy Evaluation June 2013 Complete Walk-throughs or Demonstrations Sep 20141 Not Started Perform Staffing Analysis June 2014 Not Started Modifications Evaluation Apr 2013 Complete Unit 1 N-1 Walkdown Apr 2013 Complete Unit 1 Design Engineering Oct 2013' On Track Unit I Implementation Outage Apr 2014 Not Started Sept 2014 Unit 2 Construction Walkdown Apr 2013 Complete Unit 2 Design Engineering Oct 2013' On Track Unit 2 Implementation (Startup) Apr 2014 Not Started Sept 2014 Storage Design Engineering ] IComplete =

Storage Implementation Sept 2014' Not Started Procure ] Jun 2013 On Track Dec 2013 Develop Strategies with RRC 3 Dec 2013 On Track 3 Install Off-site Delivery Station Apr 2014 On Track PWROG issues NSSS-specific June 2013 Complete guidelines Create Site-Specific FSIs June 2014 On Track Create Maintenance Procedures June 2014 Not Started Develop Training Plan Jan 2014 On Track Training Complete Sep 2014 Not Started Unit I FLEX Implementation Sep 2014 Not Started Unit 2 FLEX Implementation Sep 2014 Not Started Full Site FLEX Implementation Sep 2014 Not Started Submit Completion Report Aug 2014 Not Started Oct 2014 Notes: 1. These milestones were not included in the February 28, 2013, Overall Integrated Plan E2 of 6

a 4 Changes to Compliance Method The following is a list of changes made to the information provided in the February 28, 2013, Overall Integrated Plan (Reference 1). These changes meet the NEI 12-06 compliance method.

4.1 Revise Assumption 1 pg E-6, Note 14 pg E-9, Condensate Storage Tank (CST) references pg E-21 and E-23.

Install a new qualified Auxiliary Feedwater Supply Tank (AFWST) instead of using the Condensate Storage Tank (CST) for FLEX.

4.2 Revise reference to tank connections on pgs E-9, E-22 and E-23.

Change inlet and outlet FLEX connections from the CST to the new AFWST.

4.3 Revise the Refueling Water Storage Tank (RWST) alternate option for Reactor Coolant System (RCS) inventory on pg E-32.

Revised alternate RCS Inventory control flood option utilizing RWST as suction source for High Pressure pump. This source can be accessed utilizing the installed SI piping by routing a suction hose from the existing SIP A inlet drain valve to the High Pressure FLEX Pump inlet. The discharge of the High Pressure FLEX Pump will be routed using high pressure hose to the SIP A discharge piping.

4.4 Delete Core Exit Thermocouples (CETs) referenced on pgs E-16, 20, 27, 30, 33, 37, and Open Item 01-15, pg E-74.

CETs will not be required for flood.

4.5 Revised strategy for Attachment 1A, "Sequence of Events Timeline," pgs EAI-1 to EA1-9 for the following changes:

a. Revised and separated Timing and Deployment in both Flood and Non-flood Scenarios.

0 Revised hose deployment based on detailed review.

b. Revise 3 MWe DG from available within 40 hours4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br /> to available within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> in the event timelines.

• Taking credit for 3 MWe DG being available at 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> in timelines

• Taking credit for 3 MWe DG as a backup for the 225 kva DG E3 of 6

c. Revise reference to Spent Fuel Pool (SFP) strategy as described below:

• Utilize 3 MWe DGs to return normal SFP Cooling Pumps to service at 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

• Primary and secondary strategies swapped

• Increase in time for hose deployment to SFP from 6.9 hours1.041667e-4 days <br />0.0025 hours <br />1.488095e-5 weeks <br />3.4245e-6 months <br /> to 15 hours1.736111e-4 days <br />0.00417 hours <br />2.480159e-5 weeks <br />5.7075e-6 months <br />.

• Time for boil off of SFP level to reach 10 feet above the SFP racks increase from 37 to 85 hours9.837963e-4 days <br />0.0236 hours <br />1.405423e-4 weeks <br />3.23425e-5 months <br /> (normal decay heat load).

• Time for boil off of SFP level to reach 10 feet above the SFP racks increase from 25 to 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> (maximum decay heat load).

Note - TVA will provide a revised Attachment 1A to reflect these changes on or before the next 6-Month Update due February 28, 2014.

5 Need for Relief and Basis for the Relief Watts Bar expects to comply with the order implementation date and no relief is required at this time.

6 Open Items from Overall Integrated Plan and NRC Evaluation The following table provides a summary of the open items documented in the Overall Integrated Plan or the NRC Evaluation and the status of each item.

Open Item Description Status Number 1 The current Condensate Storage Tank (CST) is a Closed non-seismic tank that is not missile protected. The site is currently pursuing two options; the A new qualified Auxiliary qualification and hardening of the existing CST or Feedwater Supply Tank the construction of a new seismically qualified and (AFWST) instead of using missile protected CST. One of these options must the Condensate Storage be completed before the volume of the CST can be Tank (CST) for FLEX.

credited.

2 Liquefaction of haul routes for FLEX will be Started analyzed.

3 No detailed analysis has been provided regarding Closed initial FLEX fuel supplies to determine a need time for access to 7 day tank supplies or resupply of the Fuel consumption 7 day tanks. It is assumed that each FLEX spreadsheet completed to component is stored with a minimum supply of 8 show that fuel supply of hours of fuel at constant operation. This equipment will last seven assumption will need to be assessed once all days.

FLEX equipment has been purchased and equipment specifications are known.

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Open Item Description Status Number 4 No need time has been identified for action to Open protect containment. This includes actions to mitigate pressurization of containment due to steaming when reactor coolant system (RCS) vent paths have been established or actions to mitigate temperature effects associated with equipment survivability. An evaluation will be provided to prove indefinite containment coping.

5 The Phase 3 equipment staging area has not been Open determined.

6 A strategy for clearing and removing debris will be Started determined.

7 A thorough analysis of the makeup flow rate Started requirements and other equipment characteristics will be finalized during the detailed design phase of FLEX.

8 The need time for spent fuel pool (SFP) cooling Started actions (deployment of hose, venting, and alignment of makeup) was determined using worst case heat loads. This item will continue to be assessed and later action times may be acceptable. Note that the timing for this step during an outage is different, but resources will be available to complete the required actions.

9 Functional requirements for each of the Phase 3 Started strategies, equipment and components will be completed at a later time and will be provided in the six month updates to the February 28, 2013 submittal.

10 Containment temperature instrumentation is only Started available until flood waters enter the technical support center (TSC) inverter or station battery rooms. A method to monitor containment temperature, post-flood, will be developed.

11 The heating, ventilation and air conditioning Started (HVAC) analysis is preliminary, and has not been finalized.

12 Verify ability to deploy FLEX equipment to provide Open core cooling in Modes 5 and 6 with steam generators (SGs) unavailable.

13 An evaluation of the impact of FLEX response Started actions on design basis flood mode preparations will be performed. This evaluation will include the potential for extended preparation time for FLEX.

Changes which affect the Integrated Plan will be included in the six month update.

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Open Item Description Status Number 14 Further analysis will be performed to determine the Closed required timeline for implementing the 3 MWe diesel generators (DGs) as an alternate power The 3 MWe DGs are source for the loads supplied by the 225 kva 480 available within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. A Vac DGs. line will be added to 225kva timing to state that if 225s not available, then 3MWe to be started.

15 The CETs are only available until water enters the Closed auxiliary instrument room. A method to monitor CET, post flood, will be evaluated and developed, if CETs will not be required required. for flood event.

16 Strategies to address extreme cold conditions on Closed the refueling water storage tank (RWST) and/or boric acid tanks (BATs), including potential need to Irrelevant as the BATs will reenergize heaters have not been finalized, be exhausted by the time the extreme cold has an effect on the tanks.

17 Establish a contract with the Strategic Alliance for Started FLEX Emergency Response (SAFER) team in accordance with the requirements of Section 12 of NEI 12-06.

18 Manual station blackout (SBO) load shedding time Closed in References 4 and 5, Section 8.3.2.1.1, will be revised from 30 minutes to 45 minutes as supported by the 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> extended loss of alternating current power (ELAP) battery calculations.

7 Potential NRC Evaluation Impacts There are no potential impacts or Ols to the NRC Evaluation identified at this time.

8 References The following references support the updates to the Overall Integrated Plan described in this enclosure.

1. Letter from TVA to NRC, "Watts Bar'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.

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