PLA-7612, Sixth Six-Month Status Report 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 EA-13-09)

Sixth Six-Month Status Report 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 EA-13-09)

ML17166A472
Person / Time
Site:	Susquehanna
Issue date:	06/15/2017
From:	Rausch T Susquehanna, Talen Energy
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
EA-13-109, PLA-7612
Download: ML17166A472 (13)

Text

Timothy S. Rausch Susquehanna Nuclear, LLC President and Chief Nuclear Officer 769 Salem Boulevard Berwick, PA 18603 TALEN~

Tel. 570.542.3445 Fax 570.542 .1504 Timothy.Rausch@talenenergy.com ENERGY JUN 1.v 5 2017 U.S. Nuclear Regulatory Commission 10 CFR2.202 ATTN: Document Control Desk Washington, DC 20555-0001 SUSQUEHANNA STEAM ELECTRIC STATION SIXTH SIX-MONTH STATUS REPORT IN RESPONSE TO JUNE 6, 2013 COMMISSION ORDER MODIFYING LICENSES WITH REGARD TO RELIABLE HARDENED CONTAINMENT VENTS CAPABLE OF OPERATION UNDER SEVERE ACCIDENT CONDITIONS Docket Nos. 50-387 (ORDER NUMBER EA-13-109) and 50-388 PLA-7612

References:

1. 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.

2. NRC Interim Staff Guidance JLD-ISG-2013-02, "Compliance with Order EA-13-109, Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions," Revision 0, dated November 2013 (Accession No. ML13304B836 and JLD-ISG-2015-01, Revision 0, dated Apri/2015 (Accession No. ML15104A118)).

3. NRC Endorsement of industry "Hardened Containment Venting System (HCVS) Phase 1 Overall Integrated Plan Template (EA-13-109) Rev 0" (Accession No. ML14128A219).

4. NEI13-02, "Indusfly 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," Revisions 0 and 1.

5. PPL Letter (PLA-7180), "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 26, 2014.

6. PPL Letter (PLA-7269) T. S. Rausch (PPL Susquehanna, LLC) to US. NRC, "First Six-Month Status Report 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 23, 2014.

7. Susquehanna Letter (PLA-7345) T. S. Rausch (Susquehanna Nuclear, LLC) to US. NRC, "Second Six-Month Status Report 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 23, 2015.

Document Control Desk PLA-7612

8. NRC Endorsement of industry "Hardened Containment Venting System (HCVS) Phase 1 and 2 Overall Integrated Plan Template, "Revision 1, dated September 22, 2015, and Frequently Asked Questions (FAQs) 10, 11, 12, and 13 (Accession No. ML15273A141).

9. Susquehanna Letter (PLA-7421), "Combined Phase 1 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 23, 2015.

10. Susquehanna Letter (PLA-7488) T S. Rausch (Susquehanna Nuclear, LLC) to US. NRC, "Fourth Six-Month Status Report 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 29, 2016.

11 Susquehanna Letter (PLA-7550) T S. Rausch (Susquehanna Nuclear, LLC) to US. NRC, "Fifth Six-Month Status Report 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 19, 2016.

On June 6, 2013, the Nuclear Regulatory Commission ("NRC" or "Commission") issued an order (Reference 1) to PPL Susquehanna, LLC (PPL). Reference 1 was immediately effective and directs Susquehanna to install a primary containment venting capability in accordance with the requirements outlined in Attachment 2 of Reference 1.

The Order (EA-13-109) requires that licensees ofBWR facilities with Mark I and Mark II containment designs ensure that these facilities have a reliable hardened containment vent system (HCVS). The HCVS must be able to remove decay heat from the containment and maintain control of containment pressure within acceptable limits following events that result in the loss of active containment heat removal capability.

The HCVS must maintain the capability to operate under severe accident (SA) conditions resulting from an Extended Loss of AC Power (ELAP).

The Order requirements are applied in a phased approach where:

• "Phase 1 involves upgrading the venting capabilities from the containment wetwell to provide reliable, severe accident capable hardened containment vents to assist in preventing core damage and, if necessary, to provide containment venting capability during severe accident conditions." (Completed "no later than startup from the second refueling outage that begins after June 30, 2014, or June 30, 2018, whichever comes first.")

• "Phase 2 involves providing additional protections for severe accident conditions through installation of a reliable, severe accident capable drywell vent system or the development of a reliable containment venting strategy that makes it unlikely that a licensee would need to vent from the containment drywell during severe

Document Control Desk PLA-7612 accident conditions." (Completed "no later than startup from the first refueling outage that begins after June 30, 2017, or June 30, 2019, whichever comes first.")

The NRC provided an acceptable approach for complying with Order EA-13-109 through Interim Staff Guidance (JLD-ISG-2013-02 issued in November 2013 and JLD-ISG-2015-0 1 issued in April 20 15). The ISGs endorse the compliance approach presented in NEI 13-02 Revisions 0 and 1, Compliance with Order EA-13-109, Severe Accident Reliable Hardened Containment Vents, with clarifications. Except in those cases in which a licensee proposes an acceptable alternative method for complying with Order EA-13-109, the NRC staffwill use the methods described in the ISGs to evaluate licensee compliance as presented in submittals required in Order EA-13-109.

The Order also requires submittal of an overall integrated plan which will provide a description of how the requirements of the Order will be achieved (Reference 8).

Susquehanna submitted a Combined Phase 1 and Phase 2 Overall Integrated Plan (OIP) for complying with Order EA-13-109 using the methods described in NEI 13-02 and endorsed by NRC JLD-ISG-2013-02 and JLD-ISG-2015-01 (Reference 9).

Reference 1 requires submission of status reports at six-month intervals following submittal of the Combined Phase 1 and Phase 2 Overall Integrated Plan. References 2 and 4 provide direction regarding the content of the status reports. The purpose of this letter is to provide the sixth six-month status report pursuant to Section IV, Condition D, of Reference 1, that delineates progress made in implementing the requirements of Reference 1. The enclosed Status Report provides an update of milestone accomplishments since submittal of the Combined Phase 1 and Phase 2 Overall Integrated Plan and the fifth six-month 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.

Should you have any questions regarding this submittal, please contact Mr. Jason Jennings, Manager- Nuclear Regulatory Affairs at (570) 542-3155.

I declare under penalty of petjury that the foregoing is true and correct.

Executed on:

Document Control Desk PLA-7612

Enclosure:

Susquehanna Nuclear, LLC's Sixth Six-Month Status Report in Response to the 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) cc: Director, Office of Nuclear Reactor Regulation NRC Region I Mr. Rajender Auluck, NRR/JLD/PSB, NRC Mr. Brian Lee, NRR/JLD/JOMB, NRC Ms. L. H. Micewski, NRC Sr. Resident Inspector Ms. T. E. Hood, NRC Project Manager Mr. W. D. Reckley, NRR/JLD/PSB, NRC Mr. M. Shields, PA DEP/BRP

Enclosure to PLA-7612 Sixth Six-Month Status Report In Response to the 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)

Enclosure to PLA-7612 Page 1 of8 Susquehanna Nuclear, LLC's Sixth Six Month Status Report for the 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 Susquehanna Nuclear, LLC developed an Overall Integrated Plan (Reference 1, all references mentioned in this enclosure are in Section 8 of this enclosure), 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.

This six month status repmt provides updates of milestone accomplishments based on the Combined Phase 1 and 2 Overall Integrated Plan dated December 23 , 2015 (Reference 8) since submittal of the fifth six month status report (Reference 13).

Susquehanna Nuclear, LLC developed an updated and Combined Phase 1 and 2 Overall Integrated Plan (Reference 8 in Section 8), 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 altemative 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 fifth six month status report (Reference 13), including any changes to the compliance method, schedule, or need for relief/relaxation and the basis, if any. The information in this update is cuiTent as ofMay 31 , 2017.

2 Milestone Accomplishments The following milestone(s) have been completed since the submittal of the fifth six month status repmt (Reference 13 ), and are current as of May 31, 2017.

• Unit 2 Phase 1 installation is complete.

• Unit 1 Phase 1 installation has stmted.

3 Milestone Schedule Status The following provides an update to the Milestone Schedule presented in Patt 5 of the Combined Phase 1 and 2 Overall Integrated Plan (Reference 8). 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.

The revised milestone target completion dates do not impact the order implementation date.

Enclosure to PLA-7612 Page 2 of8 Comments Target

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

Phase 1 and 2 HCVS Milestone Table Submit Overall Integrated Plan Jun 2014 Complete Submit 6 Month Updates:

Update 1 Dec. 2014 Complete Update 2 Jun.2015 Complete Simultaneous with Update 3 Dec. 2015 Complete Phase 2 OIP Update 4 Jun.2016 Complete Update 5 Dec. 2016 Complete Jun. 2017 Complete with Update 6 this submittal Update 7 Dec. 2017 Not Started Update 8 Jun.2018 Not Stmied Update 9 Dec. 2018 Not Statied Phase 1 Specific Milestones Phase 1 Modifications:

Hold preliminary/conceptual design June 2014 Complete meeting Unit 2 Design Engineering Complete Apr. 2016 Complete Unit 2 Implementation Outage Mar. 2017 Complete Unit 2 Walk Through Apr. 2017 Complete Demonstration/Functional Test Unit 1 Design Engineering Complete Mat*. 2017 Complete May 2017 April2018 (Non-outage Unit 1 Implementation Outage Mar. 2018 Not Statied installation scope has statied)

Unit 1 Walk Through Apr. 2018 Not Started Demonstration/Functional Test Phase 1 Procedure Changes Active U2 Operations Procedure Changes Dec. 2016 Complete April2017 Developed U2 Maintenance Procedure Changes Dec. 2016 Complete April2017 Developed U2 Procedure Changes Active Apr. 2017 Complete U1 Operations Procedure Changes Dec. 2017 Started April2018 Developed U1 Maintenance Procedure Changes Dec. 2017 Not Started April2018 Developed

Enclosure to PLA-7612 Page 3 of8 Comments Target

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

Phase 1 and 2 HCVS Milestone Table Changed from Mar.

U1 Procedure Changes Active Apr. 2018 Not Stmied 2018 per outage schedule Phase 1 Training:

U2 Training Complete Apr. 2017 Complete U1 Training Complete Apr. 2018 Not Stmied Phase 1 Completion Unit 2 HCVS Implementation Apr. 2017 Complete Unit 1 HCVS Implementation Apr. 2018 Started Full Site HCVS Implementation Apr. 2018 Stmied 60 days after Phase Submit Phase 1 Completion Repmi Jun.2018 Not Stmied 1 compliance Phase 2 Specific Milestones Phase 2 Modifications:

Hold preliminary/conceptual design Oct. 2015 Complete meeting Unit 1 Design Engineering On-Dec. 2016 Stmied site/Complete Unit 1 Implementation Outage Mar. 2018 Not Stmied Unit 1 Walk Through Apr. 2018 Not Stmied Demonstration/Functional Test Unit 2 Design Engineering On-Dec. 2017 Started site/Complete Unit 2 Implementation Outage Mar. 2019 Not Started Unit 2 Walk Through Apr. 2019 Not Stmied Demonstration/Functional Test Phase 2 Procedure Changes Active Unit 1 Operations Procedure Changes Apr. 2018 Not Stmied Developed Unit 1 Maintenance Procedure Apr. 2018 Not Stmied Changes Developed Unit 1 Procedure Changes Active Apr. 2018 Not Started Unit 2 Operations Procedure Changes Apr. 2019 Not Started Developed Unit 2 Maintenance Procedure Apr. 2019 Not Stmied Changes Developed Unit 2 Procedure Changes Active Apr. 2019 Not Statied Phase 2 Training:

U1 Training Complete Apr. 2018 Not Stmied U2 Training Complete Apr. 2019 Not Statied

Enclosure to PLA-7612 Page 4 of8 Comments Target

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

Phase 1 and 2 HCVS Milestone Table Training Complete Apr. 2019 Not Started Phase 2 Completion Unit 1 HCVS Implementation Apr. 2018 Started Unit 2 HCVS Implementation Apr. 2019 Stmied Full Site HCVS Implementation Apr. 2019 Stmied 60 days after full site Submit Completion Rep01i Jun.2019 Not Stmied compliance 4 Changes to Compliance Method There are no changes to the compliance method as documented in the Combined Phase 1 and 2 Overall Integrated Plan (Reference 8).

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

6 Open Items from Combined Phase 1 and 2 Overall Integrated Plan and Interim Staff Evaluations The following tables provide a summary of the open items documented in the Combined Phase 1 and 2 Overall Integrated Plan or the Interim Staff Evaluation (IS E) and the status of each item.

Combined Phase 1 and 2 OIP Open Item Status Phase 1 Open Items 1 Confirm suppression pool heat capacity. Complete 2 Deployment under severe accident conditions will be confirmed for the Complete deployment of the FLEX generators credited to re-energize battery chargers.

3 Deployment under severe accident conditions will be confirmed for Complete deployment of the supplemental gas bottles.

4 The gas supply will be sized to supp01i HCVS operation for a minimum Complete of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> (a minimum of 8 valve cycles of valve operation is assumed, consistent with recommendations in HCVS-WP-02). This design assumption will require future validation in the design phase of this project.

Enclosure to PLA-7612 Page 5 of8 Combined Phase 1 and 2 OIP Open Item Status 5 An assessment of temperature and radiological conditions will be Complete performed to ensure that operating personnel can safely access and operate controls at the remote operating station, based on time constraints listed in Attachment 2 of the Overall Integrated Plan.

6 Evaluate viable options to address Hydrogen detonation concems in Complete HCVS piping to meet the requirements ofEA-13-109, Section 1.2.11 and incorporate in HCVS design. SSES will determine the method to be deployed once NRC review ofHCVS-WP-03 is complete.

7 An evaluation will be perfmmed to confi1m the HCVS power supply Complete can support HCVS operation for a minimum of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

Phase 2 Open Items 1 Revise EC-016-1043 to include simultaneous SAWA and FLEX case. Complete Ensure the SAWA flow instmment will operate in the conditions 2 Complete expected.

Phase 1 Interim Staff Evaluation Open Item Comment Status 1 Make available for NRC staff audit an evaluation that Section 3 .1 .2 Complete con:fitms that all load stripping to supp011 HCVS operation can be accomplished within fmiy five minutes of event initiation.

2 Make available for NRC staff audit the final sizing Section 3.2.1 Complete evaluation for HCVS batteries/battery charger including Section 3.2.2.4 incorporation into FLEX DG loading calculation. Section 3.2.3.1 Section 3 .2.3 .2 Section 3.2.4.1 Section 3.2.4.2 Section 3 .2.5 .1 Section 3.2.5.2 Section 3.2.6 3 Make available for NRC staff audit documentation of the Section 3.2.1 Complete HCVS nitrogen pneumatic system design including sizing Section 3.2.2.4 and location. Section 3 .2.3 .1 Section 3.2.3.2 Section 3.2.4.1 Section 3.2.4.2 Section 3.2.5.1 Section 3.2.5.2 Section 3.2.6

Enclosure to PLA-7612 Page 6 of8 4 Make available for NRC staff audit an evaluation of Section 3 .2.1 Complete temperature and radiological conditions to ensure that Section 3.2.2.3 operating personnel can safely access and operate controls Section 3.2.2.4 and suppmi equipment. Section 3.2.2.5 Section 3 .2.2.1 0 Section 3 .2.4.1 Section 3.2.4.2 Section 3.2.5.2 Section 3.2.6 5 Make available for NRC staff audit analyses demonstrating Section 3.2.2.1 Complete that HCVS has the capacity to vent the steam/energy Section 3.2.2.2 equivalent of one percent of licensed/rated thermal power (unless a lower value is justified), and that the suppression pool and the HCVS together are able to absorb and reject decay heat, such that following a reactor shutdown from full power containment pressure is restored and then maintained below the primary containment design pressure and the primary containment pressure limit.

6 Make available for NRC staff audit the seismic and tornado Section 3.2.2.3 Complete missile final design criteria for the HCVS stack.

7 Make available for NRC staff audit the descriptions of local Section 3.2.2.3 Complete conditions (temperature, radiation and humidity) anticipated Section 3.2.2.5 during ELAP and severe accident for the components Section 3.2.2.9 (valves, instrumentation, sensors, transmitters, indicators, Section 3.2.2.10 electronic, control devices, and etc.) required for HCVS venting including confirmation that the components are capable of performing their functions during ELAP and severe accident conditions.

8 Make available for NRC staff audit documentation that Section 3.2.2.5 Complete demonstrates adequate communication between the remote Section 3.2.2.10 HCVS operation locations and HCVS decision makers during ELAP and severe accident conditions.

9 Provide a description of the final design of the HCVS to Section 3.2.2.6 Complete address hydrogen detonation and deflagration.

10 Provide a description of the strategies for hydrogen control Section 3.2.2.6 Complete that minimizes the potential for hydrogen gas migration and ingress into the reactor building or other buildings.

11 Provide a justification for deviating from the Section 3.2.2.9 Complete instrumentation seismic qualification guidance specified in NEI 13-02, endorsed, in pati, by JLD-ISG-2013-02 as an acceptable means for implementing applicable requirements of Order EA-13-109.

12 Make available for NRC staff audit descriptions of all Section 3.2.2.10 Complete instrumentation and controls (existing and planned) necessary to implement this order including qualification methods.

Enclosure to PLA-7612 Page 7 of8 Phase 2 Interim Staff Evaluation Open Item Comment Status

1. Licensee to evaluate the SAWA equipment and controls, as Section 3.3.2.3 Started well as ingress and egress paths for the expected severe accident conditions (temperature, humidity, radiation) to ensure that operating personnel can safely access and operate controls and support equipment for the sustained operating period.

2. Licensee to demonstrate that SAWA components and Section 3.3 .2.3 Started connections extemal to protected buildings have been protected against the screened-in hazards of Order EA 049 for the station.

3. Licensee to demonstrate that containment failure as a result Section 3.3.3 Staried of overpressure can be prevented without a drywell vent during severe accident conditions.

4. Licensee shall demonstrate how the plant is bounded by the Section 3.3.3.1 Staried reference plant analysis that shows the SA WM strategy is successful in making it unlikely that a drywell vent is needed.

5. Licensee to demonstrate that there is adequate Section 3.3.3.4 Staried communication between the MCR and the operator at the FLEX pump during severe accident conditions.

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

8 References The following references suppmi the updates to the Combined Phase 1 and 2 Overall Integrated Plan described in this Enclosure.

1. PLA-7180, Susquehanna, LLC's 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 109)," dated June 26, 2014.

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," Revision 1, dated April2015.

4. NRC Interim Staff Guidance JLD-ISG-2013-02, "Compliance with Order EA-13-109, Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions," Revision 0, dated November 2013 (Accession No. ML13304B836).

Enclosure to PLA-7612 Page 8 of 8

5. NRC Endorsement of industry "Hardened Containment Venting System (HCVS) Phase 1 Overall Integrated Plan Template (EA-13-109) Rev 0" (Accession No. ML14128A219).

6. PPL Letter (PLA-7269) T. S. Rausch (PPL Susquehanna, LLC) to U.S. NRC, "First Six-Month Status Report 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 23, 2014.

7. Susquehanna Letter (PLA-7345) T. S. Rausch (Susquehanna Nuclear, LLC) to U.S.

NRC, "Second Six-Month Status Repmi 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 23, 2015.

8. Susquehanna Letter (PLA-7421), Susquehanna, LLC's Combined Phase 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 23,2015. (Also the Third Six-Month Update.)

9. NRC Interim Staff Guidance JLD-ISG-2015-01, "Compliance 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," Revision 0, dated April 2015 (Accession No. ML15104A118).

10. NRC Endorsement of industry "Hardened Containment Venting System (HCVS) Phase 1 and 2 Overall Integrated Plan Template," Revision 1, dated September 22, 2015, and Frequently Asked Questions (FAQs) 10, 11, 12, and 13 (Accession No. ML15273A141).

11. Susquehanna Letter (PLA-7488) T. S. Rausch (Susquehanna Nuclear, LLC) to U.S.

NRC, "Fomth Six-Month Status Repmi 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 29, 2016.

12. NRC Letter toSSES (Jon Franke), Interim Staff Evaluation for Phase 2 with 5 Open Items, August 25, 2016, ML16231A509.

13. Susquehanna Letter (PLA-7550) T. S. Rausch (Susquehanna Nuclear, LLC) to U.S.

NRC, "Fifth Six-Month Status Repmi 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 19, 2016.