RS-13-115, First 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)

First 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)

ML13241A279
Person / Time
Site:	Byron
Issue date:	08/28/2013
From:	Kaegi G Exelon Generation Co
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
EA-12-049, RS-13-115
Download: ML13241A279 (11)

Text

1 Exelon Generation Order No. EA-12-049 RS-13-115 August 28, 2013 u.s. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Byron Station, Units 1 and 2 Facility Operating License Nos. NPF-37 and NPF-66 NRC Docket Nos. STN 50-454 and STN 50-455

Subject:

First 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, " Issuance of Order to Modify Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events," dated March 12, 2012

2. NRC Interim Staff Guidance JLD-ISG-2012-01, "Compliance with Order EA-12-049, Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events," Revision 0, dated August 29,2012

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

Revision 0, dated August 2012

4. Exelon Generation Company, LLC's Initial Status Report in Response to March 12,2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated October 25,2012

5. Exelon Generation Company, LLC Overall Integrated Plan in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049), dated February 28, 2013 (RS-13-018)

On March 12, 2012, the Nuclear Regulatory Commission ("NRC" or "Commission") issued an order (Reference 1) to Exelon Generation Company, LLC (EGG). Reference 1 was immediately effective and directs EGC to develop, implement, and maintain guidance and strategies to maintain or restore core cooling, containment, and spent fuel pool cooling capabilities in the event of a beyond-design-basis external event. Specific requirements are outlined in of Reference 1.

U.S. Nuclear Regulatory Commission Integrated Plan Report to EA-12-049 August28,2013 Page 2 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 NEI 12-06, Revision 0 (Reference 3) with clarifications and exceptions identified in Reference 2. Reference 4 provided the EGC initial status report regarding mitigation strategies. Reference 5 provided the Byron Station, 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 the last status report, including any changes to the compliance method, schedule, or need for relief and the basis, if any.

This letter contains no new regulatory commitments. If you have any questions regarding this report, please contact David P. Helker at 610-765-5525.

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

Respectfully submitted, Glen T. Kaegi Director - Licensing 8( Regulatory Affairs Exelon Generation Company, LLC

Enclosure:

1. Byron Station, Units 1 and 2 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: Director, Office of Nuclear Reactor Regulation NRC Regional Administrator - Region '"

NRC Senior Resident Inspector - Byron Station, Units 1 and 2 NRC Project Manager, NRR - Byron Station, Units 1 and 2 Ms. Jessica A. Kratchman, NRR/JLD/PMB, NRC Mr. Robert J. Fretz, Jr, NRR/JLD/PMB, NRC Mr. Robert L. Dennig, NRRlDSS/SCVB. NRC Illinois Emergency Management Agency - Division of Nuclear Safety

Enclosure Byron Station, Units 1 and 2 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 (8 pages)

Byron Station, Units 1 and 2 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 1 Introduction Byron Station developed an Overall Integrated Plan (Reference 1 in Section 8), documenting the diverse and flexible strategies (FLEX), in response to Reference 2. This enclosure provides an update of milestone accomplishments since submittal of the Overall Integrated Plan, including any changes to the compliance method, schedule, or need for relief/relaxation and the basis, if any.

2 Milestone Accomplishments None 3 Milestone Schedule Status The following provides an update to Attachment 2 of the Overall Integrated Plan. It provides the activity status of each item, and whether the expected completion date has changed. The dates are planning dates subject to change as design and implementation details are developed.

Site: Byron Original Target Activity Status Revised Target Completion Date Completion Date Submit 60 Day Status Report Complete Submit Overall Integrated Complete Implementation Plan Contract with RRC Complete Submit 6 Month Updates:

Aug 2013 Update 1 Complete with this submittal Feb 2014 Update 2 Not Started Aug 2014 Update 3 Not Started Page 1 of 8

Byron Station, Units 1 and 2- First Six Month Status Report for the Implementation of FLEX August28,2013 Feb 2015 Update 4 Not Started Aug 2015 Update 5 Not Started Unit 1 Unit 2 Modification Development Aug Dec

• Phase 1 modifications Conceptual 2014 2013 Designs Complete.

Detailed Designs Started.

Aug Dec

• Phase 2 modifications Conceptual 2014 2013 Designs Complete.

Detailed Designs Started.

Aug Dec

• Phase 3 modifications Not Started 2014 2013 Unit 1 Unit 2 Modification Implementation Sept Oct

• Phase 1 modifications Not Started 2015 2014 Sept Oct

• Phase 2 modifications Not Started 2015 2014 Sept Oct

• Phase 3 modifications Not Started 2015 2014 Procedure Development Oct 2014

• Strategy procedures Started Validate Procedures (NEI 12-06, Sect.

Apr 2014 Not Started 11.4.3)

Oct 2014

• Maintenance procedures Not Started Jun 2014 Staffing analysis Not Started Oct 2014 Storage Plan and construction Conceptual Design Started Oct 2014 FLEX equipment acquisition Started Oct 2014 Training completion Not Started Aug 2014 Regional Response Center Not Started Operational Page 2 of 8

Byron Station, Units 1 and 2- First Six Month Status Report for the Implementation of FLEX August 28, 2013 Sept 2015 Unit 1 Implementation date Not Started Oct 2014 Unit 2 Implementation date Not Started 4 Changes to Compliance Method Byron FLEX Integrated Plan Changes (Reference 1)

Change 1 Section: General Integrated Plan Elements PWR - Provide a sequence of events and identify any time constraint required for success including the technical basis for the time constraint.

Reason for Change: Modification design details were refined as parts of the standardized modification design process and manual actions have been added and verified to accomplish these tasks.

Change: The time from step initiation to completion is now 5 to 50 minutes.

Change 2 Section: General Integrated Plan Elements PWR - Provide a sequence of events and identify any time constraint required for success including the technical basis for the time constraint.

Reason for Change: The information within this section was incorrectly tied to the references within that section.

Change: The (1) one hour time constraint is based on the results of MAAP analysis BW-MISC-009, dated Nov 1, 2011.

Change: The 3.6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> time constraint is based on the results of EC Evaluation 391872 dated Feb 8,2013.

Change 3 Section: General Integrated Plan Elements PWR - Provide a sequence of events and identify any time constraint required for success including the technical basis for the time constraint.

Reason for Change: Change the cool down rate wording to be consistent throughout the Byron FLEX integrated plan.

Change: 1.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> - The control room will begin to direct a cooldown of the RCS by local operation of the S/G PORVs and local control of the AF flow control valves to reduce S/G pressure down to at least 300 psia at approximately 75°F/hr.

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Byron Station, Units 1 and 2- First Six Month Status Report for the Implementation of FLEX August28,2013 Change 4 Section: General Integrated Plan Elements PWR - Provide a sequence of events and identify any time constraint required for success including the technical basis for the time constraint.

Reason for Change: Multiple operators may be used to perform this evolution instead of the implied single operator.

Change: After the Station DGs have been verified not available an operator is dispatched to the Div 2 ESF Switchgear Bus _32X and verifies all breakers are open. The same operator or an additional operator will proceed to the FLEX Building to prep and align the FLEX DG to the station connections.

Change 5 Section: Maintain Core Cooling & Heat Removal, PWR Installed Equipment Phase 1.

Reason for Change: The timeline expectation is for operators to start a cool down within 90 minutes of the event initiation, not to complete the cool down within 90 minutes as stated. This change is to align the wording in this section to be consistent with the expectations.

Change: Within 90 minutes, operators will commence cooling down the plant at approximately 7SoF/hr to 420°F (Tcold).

Change 6 Section: Maintain Core Cooling & Heat Removal, PWR Installed Equipment Phase 1.

Reason for Change: Editorial change to correct a reference Change: Change reference # three (3) to OU-AP-1 04. Shutdown Safety Management Program Byron /Braidwood Annex. Revision 17. dated September 27. 2012.

Change 7 Section: Maintain Core Cooling & Heat Removal, Phase 1, Identify Modifications.

Reason for Change: The gaps identified, preventing operation of the DDAF pump, will be resolved with a combination of modifications and manual actions instead of just modifications.

Change: The following gaps have been identified that prevent operation of the DDAF pump:

Byron station will utilize modifications and/or manual actions to close these gaps prior to FLEX implementation.

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Byron Station, Units 1 and 2- First Six Month Status Report for the Implementation of FLEX August 28,2013 Change 8 Section: Maintain RCS Inventory Control, PWR Installed Equipment Phase 1.

Reason for Change: The timeline expectation is for operators to start a cool down within 90 minutes of the event initiation, not to complete the cool down within 90 minutes as stated. This change is to align the wording in this section to be consistent with the expectations.

Change: Within 90 minutes, operators will commence cooling down the plant at approximately 75°F/hr to 420°F (Tcold).

Change 9 Section: Attachment 1A, Sequence of Events time line, Action Item Number 3.

Reason for Change: Modification design details were refined as parts of the standardized modification design process and manual actions have been added and verified to accomplish these tasks.

Change: The time from step initiation to completion is now 5 to 50 minutes.

Change 10 Section: Attachment 1A, Sequence of Events time line, Action Item Number 7.

Reason for Change: Add the word 'approximately' to align the strategy to actual plant conditions and for consistency throughout the integrated plan.

Change: Start depressurization of SlGs to 300 psia at approximately 75°F/hr cooldown with SG PORV local/manual operation. SG feed is controlled with Local/Manual operation of AFW flow control valves.

Change 11 Section: Attachment 3, Conceptual Sketches Reason for Change: Modification design details were refined as part of the standardized modification design process resulting in changes to the mechanical and electrical power conceptual sketches.

Change: Current mechanical conceptual sketch is attached to this document.

No other changes to the FLEX strategies have been identified at this time.

5 Need for Relief/Relaxation and Basis for the Relief/Relaxation Byron Station, Units 1 and 2 expects to comply with the order implementation date and no relief/relaxation is required at this time.

Page 5 of 8

Byron Station, Units 1 and 2- First Six Month Status Report for the Implementation of FLEX August28,2013 6 Open Items from Overall Integrated Plan and Draft Safety Evaluation The following tables provide a summary of the open items documented in the Overall Integrated Plan or the Draft Safety Evaluation (SE) and the status of each item.

Section Reference Overall Integrated Plan Open Item Status Key Site assumptions (p.3) Primary and secondary storage locations Started have not been selected yet; once locations are finalized implementation strategies and routes will be assessed for hazard impact.

Sequence of events (p.S) The final time line will be time validated once Not detailed designs are completed and Started procedures are developed.

Identify how strategies will be Identification of storage area and creation of Started deployed (p.6) the administrative program.

Programmatic controls (p.7) Develop an administrative program for FLEX Started responsibilities, and testing & maintenance.

Regional Response Center plan Development of Byron Station's playbook. Not (p.8) Started Key Reactor Parameters (p. Identify additional parameters that are needed Not multiple) in order to support key actions identified in the Started plant procedures/guidance or to indicate imminent or actual core damage.

Deployment Conceptual Design Develop the storage structure conceptual Started (p. multiple) design.

Maintain RCS Inventory Control, A calculation will be required for the timing of Started Phase 2 (p.22) the boration and quantity required.

Maintain Containment, Phase 1 Additional calculations will be performed to Not (p.30) evaluate containment response. Started Maintain Spent Fuel Pool Cooling, Procedure development for Initial Spent fuel Not Phase 1 (p.37) pool make-up with gravity drain from the Started RWST.

Maintain Spent Fuel Pool Cooling, Initial calculations were used to determine the Not Phase 1 (p.37) fuel pool timelines. Formal calculations will be Started performed to validate this information during development of the spent fuel pool cooling strategy detailed design.

Maintain Spent Fuel Pool Cooling, Evaluation of the spent fuel pool area for Not Phase 1, (p.37 and p.40) steam and condensation will be performed Started and used to determine if vent path strategy is needed.

Page 6 of 8

Byron Station, Units 1 and 2- First Six Month Status Report for the Implementation of FLEX August 28, 2013 Safety Functions Support, Phase Habitability conditions will be evaluated and a Not 2 (p.48) strategy will be developed to maintain Main Started Control Room.

Safety Functions Support, Phase Critical ventilation assets may be required to Not 2 (p.48) support DDAF pumps, station battery rooms, Started miscellaneous electric equipment rooms, and fuel handling building personnel habitability and/or component survivability. Specific analyses of these rooms will be performed.

Draft Safety Evaluation Open Item Status N/A N/A 7 Potential Draft Safety Evaluation Impacts There are no potential impacts to the Draft Safety Evaluation identified at this time.

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

1. Byron Station, Units 1 and 2, "Overall Integrated Plan in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events (Order Number EA-12-049)," dated February 28, 2013 (RS-13-018).

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. NE112-06 Rev. 0, Diverse and Flexible Coping Strategies (FLEX) Implementation Guide, dated August 2012.

Page 7 of 8

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