RS-16-108, Fourth Six Month Status Report for Phases 1 & 2 Integrated Plan in Response to 06/06/2013 Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (EA-13-1

Fourth Six Month Status Report for Phases 1 & 2 Integrated Plan in Response to 06/06/2013 Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (EA-13-10

ML16182A011
Person / Time
Site:	Limerick
Issue date:	06/30/2016
From:	Jim Barstow Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
EA-13-109, RS-16-108
Download: ML16182A011 (13)

Text

Exelon Generation ~)

RS-16-108 June 30, 2016 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Limerick Generating Station, Units 1 and 2 Renewed Facility Operating License Nos. NPF-39 and NPF-85 NRC Docket Nos. 50-352 and 50-353 Order No. EA-13-109

Subject:

Fourth Six-Month Status Report For Phases 1 and 2 Overall Integrated Plan in Response to June 6, 2013 Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (Order Number EA-13-109)

References:

1. NRC Order Number EA-13-109, "Issuance of Order to Modify Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions," dated June 6, 2013

2. NRC Interim Staff Guidance JLD-ISG-2015-01, "Compliance with Phase 2 Order EA-13-109, Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation under Severe Accident Conditions", Revision 0, dated April 2015

3. NEI 13-02, "Industry Guidance for Compliance With Order EA-13-109, BWR Mark I & II Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions", Revision 1, dated April 2015

4. Exelon Generation Company, LLC's Answer to June 6, 2013, Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (Order Number EA-13-109), dated June 26, 2013

5. Exelon Generation Company, LLC Phase 1 Overall Integrated Plan in Response to June 6, 2013 Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (Order Number EA-13-109), dated June 30, 2014 (RS-14-060)

6. Exelon Generation Company, LLC First Six-Month Status Report Phase 1 Overall Integrated Plan in Response to June 6, 2013 Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (Order Number EA-13-109), dated December 17, 2014 (RS-14-304)

7. Exelon Generation Company, LLC Second Six-Month Status Report Phase 1 Overall Integrated Plan in Response to June 6, 2013 Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (Order Number EA-13-109), dated June 30, 2015 (RS-15-150)

U.S. Nuclear Regulatory Commission Integrated Plan Report to EA-13-109 June 30, 2016 Page 2

8. Exelon Generation Company, LLC Phase 1 (Updated) and Phase 2 Overall Integrated Plan in Response to June 6, 2013 Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (Order Number EA-13-109), dated December 15, 2015 (RS-15-301)

9. NRC letter to Exelon Generation Company, LLC, Limerick Generating Station, Units 1 and 2 - Interim Staff Evaluation Relating to Overall Integrated Plan in Response to Phase 1 of Order EA-13-109 (Severe Accident Capable Hardened Vents) (TAC Nos. MF4418 and MF4419), dated April 1, 2015 On June 6, 2013, the Nuclear Regulatory Commission ("NRC" or "Commission") issued an Order (Reference 1) to Exelon Generation Company, LLC (EGC). Reference 1 was immediately effective and directs EGC to require their BWRs with Mark I and Mark II containments to take certain actions to ensure that these facilities have a hardened containment vent system (HCVS) to remove decay heat from the containment, and maintain control of containment pressure within acceptable limits following events that result in loss of active containment heat removal capability while maintaining the capability to operate under severe accident (SA) conditions resulting from an Extended Loss of AC Power (ELAP). Specific requirements are outlined in Attachment 2 of Reference 1.

Reference 1 required submission of an Overall Integrated Plan (OIP) by June 30, 2014 for Phase 1 of the Order, and an OIP by December 31, 2015 for Phase 2 of the Order. The interim staff guidance (Reference 2) provides direction regarding the content of the OI P for Phase 1 and Phase 2. Reference 2 endorses industry guidance document NEI 13-02, Revision 1 (Reference 3) with clarifications and exceptions identified in Reference 2. Reference 4 provided the EGC initial response regarding reliable hardened containment vents capable of operation under severe accident conditions. Reference 5 provided the Limerick Generating Station, Units 1 and 2, Phase 1 OIP pursuant to Section IV, Condition D.1 of Reference 1. References 6 and 7 provided the first and second six-month status reports pursuant to Section IV, Condition D.3 of Reference 1 for Limerick Generating Station. Reference 8 provided the Limerick Generating Station, Units 1 and 2, Phase 1 updated and Phase 2 OIP pursuant to Section IV, Conditions D.2 and 0.3 of Reference 1.

The purpose of this letter is to provide the fourth six-month update report for Phases 1 and 2, pursuant to Section IV, Condition D.3 of Reference 1, that delineates progress made in implementing the requirements of Reference 1 for Limerick Generating Station, Units 1 and 2.

The enclosed report provides an update of milestone accomplishments since the last status report, including any changes to the compliance method, schedule, or need for relief and the basis, if any. The enclosed report also addresses the NRC Interim Staff Evaluation open items contained in Reference 9.

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

U.S. Nuclear Regulatory Commission Integrated Plan Report to EA-13-109 June 30, 2016 Page 3 I declare under penalty of perjury that the foregoing is true and correct. Executed on the 30th day of June 2016.

Respectfully submitted, James Barstow Director - Licensing & Regulatory Affairs Exelon Generation Company, LLC

Enclosure:

Limerick Generating Station, Units 1 and 2 Fourth Six-Month Status Report for Phases 1 and 2 Implementation of Order EA-13-109, Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions cc:

Director, Office of Nuclear Reactor Regulation NRC Regional Administrator - Region I NRC Senior Resident Inspector - Limerick Generating Station NRC Project Manager, NRR - Limerick Generating Station Mr. Raj Auluck, NRR/JLD/TSD/JCBB, NRC Mr. John D. Hughey, NRR/JLD/JOMB, NRC Director, Bureau of Radiation Protection - Pennsylvania Department of Environmental Resources R. R. Jana ti, Chief, Division of Nuclear Safety, Pennsylvania Department of Environmental Protection, Bureau of Radiation Protection

Enclosure Limerick Generating Station, Units 1 and 2 Fourth Six.. Month Status Report for Phases 1 and 2 Implementation of Order EA.. 13.. 109, Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (9 pages)

Enclosure Limerick Generating Station, Units 1 and 2 Fourth Six-Month Status Report for Phases 1 and 2 Implementation of Order EA-13-109, "Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions" 1 Introduction Limerick Generating Station (LGS) developed an Overall Integrated Plan (Reference 1 ),

documenting the installation of a Hardened Containment Vent System (HCVS) that provides a reliable hardened venting capability for pre-core damage and under severe accident conditions, including those involving a breach of the reactor vessel by molten core debris, in response to Reference 2. Starting with this six month status report, updates of milestone accomplishments will be based on the combined Phases 1 and 2 Overall Integrated Plan dated December 15, 2015.

LGS developed an updated and combined Phases 1 and 2 Overall Integrated Plan (Reference 1 ), documenting:

1. The installation of a Hardened Containment Vent System (HCVS) that provides a reliable hardened venting capability for pre-core damage and under severe accident conditions, including those involving a breach of the reactor vessel by molten core debris, in response to Reference 2.

2. An alternative venting strategy that makes it unlikely that a drywell vent is needed to protect the containment from overpressure related failure under severe accident conditions, including those that involve a breach of the reactor vessel by molten core debris, in response to Reference 2.

This enclosure provides an update of milestone accomplishments since submittal of the combined Phases 1 and 2 Overall Integrated Plan, including any changes to the compliance method, schedule, or need for relief/relaxation and the basis, if any.

2 Milestone Accomplishments The following milestone(s) have been completed since the December 15, 2015 status report (Reference 1) and are current as of May 15, 2016.

Fourth Six-Month Update (complete with this submittal) 3 Milestone Schedule Status The following provides an update to Attachment 2 of the combined Phases 1 and 2 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.

Page 1of9

Limerick Generating Station, Units 1 and 2 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Comments Target

{Include date Milestone Completion Activity Status Date changes in this column}

Phases 1 and 2 HCVS Milestone Table Submit Overall Integrated Plan (Phase 1)

Jun 2014 Complete Reference 7 Submit 6 Month Updates Update 1 Dec 2014 Complete Reference 8 Update 2 Jun 2015 Complete Reference 9 Update 3 [Simultaneous with Phase 2 Dec 2015 Complete Reference 1 OIP]

Update 4 Jun 2016 Complete with this submittal Update 5 Dec 2016 Not Started Update 6 Jun 2017 Not Started Update 7 Dec 2017 Not Started Update 8 Jun 2018 Not Started Update 9 Dec 2018 Not Started Phase 1 Specific Milestones Phase 1 Modifications Hold preliminary/conceptual design Jun 2014 Complete meeting Modifications Evaluation Mar 2017 Started Unit 1 Design Engineering On-Mar 2017 Started site/Complete Unit 1 Implementation Outage Apr2018 Not Started Unit 1 Walk Through Apr2018 Not Started Demonstration/Functional Test Unit 2 Design Engineering On-Nov 2016 Started site/Complete Unit 2 Walk Through May 2017 Not Started Demonstration/Functional Test Page 2of9

Limerick Generating Station, Units 1 and 2 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Comments Target

{Include date Milestone Completion Activity Status Date changes in this column}

Phases 1 and 2 HCVS Milestone Table Unit 2 Implementation Outage May 2017 Not Started Phase 1 Procedure Changes Active Unit 1 Operations Procedure Changes Feb 2018 Not started Developed Unit 1 Site Specific Maintenance Feb 2018 Not started Procedure Developed Date moved to Unit 1 Procedure Changes Active Apr2018 Not started match outage date Unit 2 Operations Procedure Changes Feb 2017 Not started Developed Unit 2 Site Specific Maintenance Feb 2017 Not started Procedure Developed Date moved to Unit 2 Procedure Changes Active May 2017 Not started match outage date Phase 1 Training Unit 1 Training Complete Feb 2018 Not started Unit 2 Training Complete Feb 2017 Not started Phase 1 Completion Unit 1 HCVS Implementation Apr2018 Not Started Unit 2 HCVS Implementation May 2017 Not Started Full Site HCVS Implementation Apr 2018 Not Started Submit Unit 1 Completion Report [with Date moved to Jun 2018 Not Started match 60 days

. Phase 2 compliance report]

after outage Submit Unit 2 Completion Report [with Date moved to Jul2019 Not Started match 60 days Phase 2 compliance report]

after outage Page 3of9

Limerick Generating Station, Units 1 and 2 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Comments Target

{Include date Milestone Completion Activity Status Date changes in this column}

Phases 1 and 2 HCVS Milestone Table Phase 2 Specific Milestones Phase 2 Modifications Hold preliminary/conceptual design Jun 2016 Not started meeting Modifications Evaluation Feb 2019 Not Started Unit 1 Design Engineering On-Moved to align Feb 2017 Not Started with outage site/Complete milestone Unit 1 Implementation Outage Apr2018 Not Started Unit 1 Walk Through Apr2018 Not Started Demonstration/Functional Test Unit 2 Design Engineering On-Moved to align Mar 2018 Not Started with outage site/Complete milestone Unit 2 Walk Through Apr2019 Not Started Demonstration/Functional Test Unit 2 Implementation Outage May 2019 Not Started Phase 2 Procedure Changes Active Unit 1 Operations Procedure Changes Feb 2018 Not Started Developed Unit 1 Site Specific Maintenance Feb 2018 Not Started Procedure Developed Unit 1 Procedure Changes Active Apr 2018 Not Started Unit 2 Operations Procedure Changes Feb 2019 Not Started Developed Unit 2 Site Specific Maintenance Feb 2019 Not Started Procedure Developed Unit 2 Procedure Changes Active May 2019 Not Started Page 4 of 9

Limerick Generating Station, Units 1 and 2 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Comments Target

{Include date Milestone Completion Activity Status Date changes in this column}

Phases 1 and 2 HCVS Milestone Table Phase 2 Training Unit 1 Training Complete Feb 2018 Not started Unit 2 Training Complete Feb 2019 Not started Phase 2 Completion Unit 1 HCVS Implementation Apr2018 Not Started Unit 2 HCVS Implementation May 2019 Not Started Date moved to Full Site HCVS Implementation May 2019 Not Started match outage date Submit Unit 1 Phase 1 and Phase 2 Completion Report [60 days after Unit Jun 2018 Not Started 1 compliance]

Submit Unit 2 Phase 1 and Phase 2 Date moved to Completion Report [60 days after Unit Jul2019 Not Started match outage 2 compliance]

date 4 Changes to Compliance Method There are no changes to the compliance method as documented in the combined Phases 1 and 2 Overall Integrated Plan (Reference 1 ).

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

Page 5 of 9

Limerick Generating Station, Units 1 and 2 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 6 Open Items from Combined Phases 1 and 2 Overall Integrated Plan and Interim Staff Evaluations The following tables provide a summary of the open items documented in the combined Phases 1 and 2 Overall Integrated Plan or the Interim Staff Evaluation (ISE) and the status of each item.

Combined Phase 1 and Phase 2 OIP Open Items Status Phase 1 Open Items 01-1 Determine how Motive Power and/or HCVS Battery Power Closed to /SE -1 will be disabled during normal operation.

01-2 Confirm that the Remote Operating Station (ROS) will be in Closed to /SE-3 an accessible areafollowing a Severe Accident (SA).

01-3 Determine wetwell line size to meet 1 % venting criteria.

Closed to /SE-4 01-4 Confirm suppression pool heat capacity.

Closed to /SE-4 01-5 Determine the approach for combustible gases.

Closed to /SE-9 and /SE-JO 01-6 Provide procedures for HCVS Operation.

Closed to /SE-13 01-7 Verify the external piping consists solely of large bore Started piping and its supports have less than 300 square feet of cross section.

01-8 Evaluate drywell pressure indication for environmental Not Started qualifications to ensure this instrument can survive for 7 days after an event.

01-9 Determine Performance Criteria for Motive gas Cylinders, Started Argon Cylinders, FLEX Diesel Generator, and FLEX (SA WA) pump pressure at 500 gpm.

0/-10 Perform radiological evaluationfor Phase 1 vent line Not Started impact on ERO response actions.

Phase 2 Open Items None Phase 1 Interim Staff Evaluation Open Items Status ISE-1 Make available for NRC staff audit documentation of a Started method to disable HCVS during normal operation to provide assurances against inadvertent operation that also minimizes actions to enable HCVS operation Page 6of9

ISE-2 ISE-3 ISE-4 ISE-5 ISE-6 ISE-7 Limerick Generating Station, Units 1 and 2 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Phase 1 Interim Staff Evaluation Open Items Status following an ELAP.

Make available for NRC staff audit the final sizing Not Started evaluationfor HCVS batteries/battery charger including incorporation into FLEX DG loading calculation.

• Make available for NRC staff audit an evaluation of Not Started temperature and radiological conditions to ensure that operating personnel can safely access and operate controls and support equipment.

Make available for NRC staff audit analyses Started demonstrating that HCVS has the capacity to vent the The required one percent steam/energy equivalent of one percent of licensed/rated capacity at the lower of thermal power (unless a lower value is justified), and Primary Containment Pressure that the suppression pool and the HCVS together are Limit or containment design able to absorb and reject decay heat, such that following pressure will be verified using a reactor shutdown from full power containment Reactor Excursion and Leak pressure is restored and then maintained below the Analysis Program (RELAP). In primary containment design pressure and the primary addition, Modular Accident contailunent pressure limit.

Analysis Program (MMP) analyses will be credited to verify that venting can be delayed for at least three hours and that anticipatory venting can be credited to maintain Reactor Core Isolation Coolin~ ( RCIC) functional.

Make available for NRC staff audit the seismic and Started tornado missile final design criteriafor the HCVS stack.

As discussed in the December 2015 OIP submittal, the Limerick design complies with the reasonable tornado protection criteria of "Missile Evaluation for HCVS Components 30 feet above Grade" HCVS-WP-04 (Reference JO).

Make available for NRC staff audit the descriptions of Not Started local conditions (temperature, radiation and humidity) anticipated during ELAP and severe accident for the components (valves, instrumentation, sensors, transmitters, indicators, electronics, control devices, etc.) requiredfor HCVS venting including confirmation that the components are capable of peiforming their functions during ELAP and severe accident conditions.

Make available for NRC staff audit documentation of the Not Started HCVS nitrogen pneumatic system design including sizing and location.

Page 7of9

ISE-8 ISE-9 ISE-10 ISE-11 ISE-12 ISE-13 Limerick Generating Station, Units 1 and 2 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 Phase 1 Interim Staff Evaluation Open Items Status Make available for NRC staff audit documentation that Not Started demonstrates adequate communication between the remote HCVS operation locations and HCVS decision makers during ELAP and severe accident conditions.

Provide a description of the final design of the HCVS to Started address hydrogen detonation and deflagration.

As discussed in the December 2015 OIP submittal, the Limerick design will use an Argon purge system to prevent the possibility of hydrogen detonation and deflagration.

Provide a description of the strategies for hydrogen Started control that minimizes the potential for hydrogen gas As discussed in the December migration and ingress into the reactor building or other 2015 OJP, the Limerick buildings.

wetwell vent line for each unit has a dedicated HCVS flowpathfrom the wetwell penetration to the outside with no interconnected system. The discharge point nieets the guidance of "HCVS Release Point", HCVS-FAQ-04 (Reference 11).

Make available for NRC staff audit documentation of a Not Started seismic qualification evaluation of HCVS components.

Make available for NRC staff audit descriptions of all Not Started instrumentation and controls (existing and planned) necessary to implement this order including qualification methods.

Make available for NRC staff audit the procedures for Not Started HCVS operation.

Phase 2 Interim Staff Evaluation Open Items Status Phase 2 /SE not issued 7

Interim Staff Evaluation Impacts There are no potential impacts to the Interim Staff Evaluation(s) identified at this time.

Page 8of9

Limerick Generating Station, Units 1 and 2 Fourth Six-Month Status Report for the Implementation of HCVS Phases 1 and 2 June 30, 2016 8 References The following references support the updates to the combined Phases 1 and 2 Overall Integrated Plan described in this attachment.

1. Limerick Generating Station, Units 1 and 2, Overall Integrated Plan in Response to June 6, 2013 Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (Order Number EA-13-109)," dated December 15, 2015

2. NRC Order Number EA-13-109, "Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions" dated June 6, 2013

3. NEI 13-02, "Industry Guidance for Compliance with NRC Order EA-13-109, 'To Modify Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions, 11 Revision 1, dated April 2015

4. NRC Interim Staff Guidance JLD-ISG-2013-02, 11Compliance with Order EA-13-109, Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions, 11 Revision 0, dated November 2013 (Accession No. ML133048836)

5. NRC Endorsement of Industry "Hardened Containment Venting System (HCVS) Phase 1 Overall Integrated Plan Template (EA-13-109) Rev O," dated May 14, 2014 (Accession No. ML14128A219)

6. NRC Interim Staff Guidance JLD-ISG-2015-01, 11Compliance with Phase 2 of Order EA-13-109, Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions, 11 Revision 0, dated April 2015 (Accession No. ML15104A118)

7. Exelon Generation Company, LLC, Phase 1 Overall Integrated Plan in Response to June 6, 2013 Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (Order Number EA-13-109), dated June 30, 2014

8. Exelon Generation Company, LLC, First Six-Month Status Report for Phase 1 Overall Integrated Plan in Response to June 6, 2013 Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (Order Number EA-13-109), dated December 17, 2014

9. Exelon Generation Company, LLC, Second Six-Month Status Report for Phase 1 Overall Integrated Plan in Response to June 6, 2013 Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (Order Number EA-13-109), dated June 30, 2015

10. Missile Evaluation for HCVS Components 30 feet Above Grade, HCVS-WP-04, Revision O (ML15244A923), 8/8/2015

11. HCVS Release Point, HCVS-FAQ-04, Revision 1, (ML14120A289), 4/14/ 2014 Page 9of9