CNL-18-060, Completion of Required Action for NRC Order EA-13-109, Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions

Completion of Required Action for NRC Order EA-13-109, Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions

ML18169A178
Person / Time
Site:	Browns Ferry
Issue date:	05/31/2018
From:	James Shea Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
CAC MF4542, CNL-18-060, EA-13-109
Download: ML18169A178 (17)

Text

Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402 CNL-18-060 May 31, 2018 10 CFR 2.202 10 CFR 50.4 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Browns Ferry Nuclear Plant, Unit 3 Renewed Facility Operating License No. DPR-68 NRC Docket No. 50-296

Subject:

Tennessee Valley Authority, Browns Ferry Nuclear Plant, Unit 3, Completion of Required Action for NRC Order EA-13-109, Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (CAC No. MF4542)

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 (ML13143A321)

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 14, 2013 (ML13304B836)

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 23, 2015 (ML15113B318)

4. Letter from TVA to NRC, Tennessee Valley Authoritys 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 (Order Number EA-13-109), dated June 30, 2014 (ML14181B169)

5. Letter from TVA to NRC, Tennessee Valley Authority's Browns Ferry Nuclear Plant First 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), dated December 19, 2014 (ML14353A428)

U.S. Nuclear Regulatory Commission CNL-18-060 Page 2 May 31, 2018

6. Letter from NRC to TVA, Browns Ferry Nuclear Plant, Units 1, 2, and 3 -

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. MF4540, MF4541 and MF4542), dated February 11, 2015 (ML14356A362)

7. 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 29, 2015 (ML15104A118)

8. Letter from TVA to NRC, Tennessee Valley Authority's Browns Ferry Nuclear Plant Second 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), dated June 29, 2015 (ML15181A338)

9. Letter from TVA to NRC, Tennessee Valley Authority's Browns Ferry Nuclear Plant Third Six-Month Status Report and Phase 1 and Phase 2 Overall Integrated Plan 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), dated December 29, 2015 (ML15365A554)

10. Letter from TVA to NRC, Tennessee Valley Authoritys Browns Ferry Nuclear Plant Fourth 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), dated June 30, 2016 (ML16182A517)

11. Letter from TVA to NRC, Tennessee Valley Authority Browns Ferry Nuclear Plants Fifth 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), dated December 22, 2016 (ML16357A577)

12. Letter from TVA to NRC, Tennessee Valley Authority Browns Ferry Nuclear Plants 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), dated June 30, 2017 (ML17181A333)

13. Letter from TVA to NRC, Tennessee Valley Authority Browns Ferry Nuclear Plants Seventh Sixth-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), dated December 20, 2017 (ML17354A250)

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ENCLOSURE Tennessee Valley Authority, Browns Ferry Nuclear Plant, Unit 3, Completion of Required Action for NRC Order EA-13-109, Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions BACKGROUND On June 6, 2013, the Nuclear Regulatory Commission (NRC) issued Order EA-13-109, Order Modifying Licenses with Regard to Requirements for Reliable Hardened Containment Vents (HCVS) Capable of Operation Under Severe Accident Conditions (Reference 1), to Tennessee Valley Authority (TVA). This Order was immediately effective and directs the Browns Ferry Nuclear Plant (BFN), Units 1, 2, and 3, to install 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 Order EA-13-109. BFN developed an Overall Integrated Plan (OIP) (Phase 1 in Reference 2 and Phases 1 and 2 in Reference 5) to provide HCVS. The information provided herein, as well as the implementation of the OIP, documents full compliance for BFN, Unit 3, in response to the Order (Reference 1).

OPEN ITEM RESOLUTION The Phase 1 and 2 NRC Interim Staff Evaluation (ISE) Open Items (References 10 and 11, respectively) have been addressed and documented in the subsequent Order EA-13-109 six-month status reports (References 3-9). A list of the ISE open items and a summary of the closure action is listed below:

Browns Ferry Nuclear Plant HCVS Response Phase 1 ISE Open Items 1 Make available for NRC staff An evaluation of temperature and radiological conditions audit an evaluation of was performed to ensure that Operating personnel can temperature and radiological safely access and operate controls at the Remote conditions to ensure that Operating Station located in the Diesel Buildings and in operating personnel can safely the Reactor Building. This evaluation is documented in access and operate controls Unit 3 DCN 71391 Design Change Technical Evaluation.

and support equipment. MDQ0000642015000351, HCVS Operator (Mission) Dose Calculation, and MDQ0009992014000291, Temperature Response of the Reactor Building Following an Extended Loss of AC Power, were used to validate the evaluation.

This ISE Open Item was closed as documented in Reference 12.

2 Make available for NRC audit For Unit 3, 3-EOI Appendix-13 Revision 6 was revised to documentation that procedure include venting for loss of DC power.

1/2/3-EOI Appendix-13 has This ISE Open Item was closed as documented in been revised to include venting Reference 12.

for loss of DC power.

CNL-18-060 E-1

Browns Ferry Nuclear Plant HCVS Response Phase 1 ISE Open Items 3 Make available for NRC staff Calculation EDQ0009992013000202, 250V DC Unit audit documentation Batteries, 1, 2, & 3 Evaluation for the Beyond Design demonstrating that all load Basis External Event (BDBEE) Extended Loss of AC sheds will be accomplished Power (ELAP), has been issued to determine load within one hour of event shedding impact on the unit batteries. The performance of initiation and will occur in an the load shed is directed by 0-FSI-1, FLEX Support area not impacted by a Instruction, and performed in accordance with 0-FSI-3F, possible radiological event. Load Shed of 250V Main Bank Battery 1, 2, 3. The load shed is performed in the Control Bay and Electrical Board rooms only and will not require entry into areas that are impacted by a possible radiological event.

This ISE Open Item was closed as documented in Reference 12.

4 Make available for NRC staff A conceptual meeting was held in November 2014, and a audit documentation that staging plan was used to separate the existing Hardened demonstrates that operating Wetwell Vent (HWWV) from the HCVS. The HCVS has units that have not been implemented on Unit 3.

implemented the order will be This ISE Open Item was closed as documented in able to vent through the Reference 12.

existing vent system unaffected by the implementation of HCVS on other units.

5 Make available for NRC staff The existing wetwell vent and the HCVS have been audit analyses demonstrating designed for 1 percent of rated thermal power at Extended that HCVS has the capacity to Power Uprate (3952 MWt) conditions. This analysis is vent the steam/energy available and documented in Calculation equivalent of one percent of NDQ0000642015000341, HCVS MAAP Analysis.

licensed/rated thermal power This ISE Open Item was closed as documented in (unless a lower value is Reference 12.

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.

CNL-18-060 E-2

Browns Ferry Nuclear Plant HCVS Response Phase 1 ISE Open Items 6 Make available for NRC staff A communication system has been implemented audit documentation that (DCN 70852) that uses hand held radios for demonstrates adequate communication between the main control room (MCR) and communication between the the remote operating station. This Radio System consists remote HCVS operation of a Ultra High Frequency (UHF)/Very High Frequency locations and HCVS decision (VHF) trunked system and an independent VHF channel makers during ELAP and (F4). The In-plant Radio System is accessed by handheld severe accident conditions. radios. The In-plant Radio System has normal and emergency diesel generator backed power supply. The radio system is powered from two Class 1E redundant power sources, the 480V DG Auxiliary Boards A and B.

Primary power source will be from the 480V DG Auxiliary Board A via a second 480-208V/120V transformer/distribution center. In the event of loss of primary power source, power to radio equipment will be automatically transferred to backup source via transfer switches located in each cabinet, with exception of cabinet 4, which receives power via cabinet 1 transfer switch.

Backup power source includes Uninterrupted Power Supply (UPS) with battery capacity to supply four (4) UHF channels for three hours. Therefore, in this configuration, capacity is reduced from five simultaneous conversations to three. The loads supplied via UPS can be alternatively supplied from a portable generator via a transfer switch (0-FSI-4B).

UPS conservation can be accomplished by switching off one of the two UPSs until such time the active UPS reaches low level. Then, the UPS previously switched off can be returned to service extending the overall time the radio system can remain operable without portable generator power to approximately 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

BFN maintains a large number of handheld radios, batteries, and charging units. The FLEX program does not maintain dedicated handheld radios. These units, spare batteries, and chargers will be gathered if not readily available in the control rooms.

Handheld Radios can additionally be operated in Radio-to-Radio mode enabling communications not affected by shielding or distance.

This ISE Open Item was closed as documented in Reference 12.

CNL-18-060 E-3

Browns Ferry Nuclear Plant HCVS Response Phase 1 ISE Open Items 7 Make available for NRC staff An evaluation was performed and concluded that the audit documentation of an containment isolation valves will open under the maximum evaluation verifying the expected differential pressure and is documented in existing containment isolation Flowserve Report RAL-70181, Design Review Report of valves, relied upon for the Size 14 Class 150 Wafer Butterfly Valve with Pneumatic HCVS, will open under the Actuator, Revision 1.

maximum expected differential This ISE Open Item was closed as documented in pressure during BDBEE and Reference 12.

severe accident wetwell venting.

8 Make available for NRC staff Electrical and instrument and control components were audit documentation of a procured as seismically qualified or as Seismic Class I to seismic qualification evaluation ensure their functionality following a seismic event.

of HCVS components. Seismic qualification reports of HCVS components are available for audit.

This ISE Open Item was closed as documented in Reference 12.

9 Make available for NRC staff Instrumentation and controls necessary to implement this audit descriptions of all order including equipment description, location, and instrumentation and controls qualifications are available for audit.

(existing and planned) This ISE Open Item was closed as documented in necessary to implement this Reference 12.

order including qualification methods.

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

transmitters, indicators, This ISE Open Item was closed as documented in electronics, control devices, Reference 12.

and etc.) required for HCVS venting including confirmation that the components are capable of performing their functions during ELAP and severe accident conditions.

CNL-18-060 E-4

Browns Ferry Nuclear Plant HCVS Response Phase 1 ISE Open Items 11 Make available for NRC staff HCVS batteries/battery charger final sizing evaluation was audit the final sizing evaluation performed and documented in the Design Change for HCVS batteries/battery Technical Evaluation of DCN 71391 for Unit 3. There is no charger including incorporation incorporation of the HCVS battery/battery charger required into FLEX DG loading into the FLEX DG loading calculation due to no plans or calculation. requirements to recharge the HCVS battery after depletion. The HCVS electrical loads will be aligned back to their normal power supply which is the Unit Battery.

The recharging of the Unit Battery is incorporated into the FLEX DG loading calculations. Calculation EDQ0003602014000281 Revision 3, Electrical Evaluation for Portable Power Supply for Unit Battery Chargers, and calculation EDQ0003602015000325 Revision 1, Electrical Evaluation for 4KV Spare FLEX Turbine Generators, were used to validate the evaluation.

This ISE Open Item was closed as documented in Reference 12.

12 Make available for NRC staff The HCVS evaluation has been completed and audit documentation of the documented in DCN 71391 for Unit 3 and calculation HCVS nitrogen pneumatic MDQ0000322015000347, HCVS Nitrogen System Sizing system design including sizing Analysis. As documented in DCN 71391 Design Change and location. Technical Evaluation (Page 26 of 69), there are 9 Nitrogen Cylinders required for Unit 3 for 7 days of Hardened Vent operation. 24 Nitrogen Cylinders are required for Units 2 and 3 for 7 days simultaneous operation. There are 5 Nitrogen Cylinders installed to support Hardened Vent operation for Units 2 and 3. There are 6 Nitrogen Cylinder carts with 6 Nitrogen Cylinders on each cart available in the FLEX Storage building with no other committed use of them.

This ISE Open Item was closed as documented in Reference 12.

13 Make available for NRC staff Tornado and seismic missile criteria are located in the audit the seismic and tornado Primary Containment System (64A) Design Criteria missile final design criteria for Document (DCD). As part of DCN 71391 for Unit 3, a the HCVS stack. markup reflecting these changes has been generated and will be incorporated in the next revision of the DCD per TVA process.

This ISE Open Item was closed as documented in Reference 12.

CNL-18-060 E-5

Browns Ferry Nuclear Plant HCVS Response Phase 1 ISE Open Items 14 Provide a description of the The final design of HCVS at BFN to address hydrogen final design of the HCVS to detonation and deflagration is the installation of a check address hydrogen detonation valve near the vent discharge release point. A description and deflagration. of this design is contained in the Technical Evaluation for DCN 71391 for Unit 3.

This ISE Open Item was closed as documented in Reference 12.

15 Provide a description of the The HCVS provides a direct vent path from the wetwell to strategies for hydrogen control an exhaust point above the Reactor Building Roof in that minimizes the potential for accordance with NEI 13-02, Section 4.1.5. This is a leak hydrogen gas migration and tight system with no boundary valves outside the primary ingress into the reactor containment isolation valves (PCIVs) that would allow building or other buildings hydrogen gas migration and ingress into the Reactor Building or other buildings. Per NEI 13-02 Frequently Asked Question FAQ-04, an effluent release velocity of 8000 feet per minute will assure that the effluent plume will not be entrained into the roof recirculation zone of a given building. A description of this design is contained in the Technical Evaluation for DCN 71391 for Unit 3.

This ISE Open Item was closed as documented in Reference 12.

16 Provide design details that The BFN design includes a separate HCVS stack for each minimize unintended cross unit as well as meeting the testing criteria and valve flow of vented fluids within a requirements for PCIVs and control and boundary valves.

unit and between units on the A description of this design is contained in the Technical site. Evaluation for DCN 71391 for Unit 3.

This ISE Open Item was closed as documented in Reference 12.

Browns Ferry Nuclear Plant HCVS Response Phase 2 ISE Open Items 1 Licensee to perform a Calculation MDN0003602014000233, Hydraulic Analysis hydraulic evaluation to ensure for Fukushima FLEX Connection Modifications, was flow adequacy can be met for revised to include a bounding case that concluded that a all 3 units using 1 FLEX pump single FLEX pump (with booster pump) can provide to support SAWA flow 500 gallons per minute (gpm) to the Unit 3 reactor requirement. pressure vessel (RPV) at an RPV pressure of 106 pounds per square inch gage (psig) in response to a Severe Accident Water Addition (SAWA) event.

This ISE Open Item was closed as documented in Reference 12.

CNL-18-060 E-6

Browns Ferry Nuclear Plant HCVS Response Phase 2 ISE Open Items 2 Licensee to evaluate the Equipment and Controls SAWA equipment and controls, Plant instrumentation for Severe Accident Water as well as the ingress and Management (SAWM) is qualified to NRC Regulatory egress paths for the expected Guide (RG) 1.97 or equivalent and is considered qualified severe accident conditions for the sustained operating period without further (temperature, humidity, evaluation. The following plant instruments are qualified radiation) for the sustained to RG 1.97:

operating period.

Drywell (DW) Pressure Indicators, 1,2,3-PI-64-67B, and Suppression Pool Level Indicators, 1,2,3-LI-64-159A.

Passive components that do not need to change state after initially establishing SAWA flow do not require evaluation beyond the first 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, at which time they are expected to be installed and ready for use to support SAWA/SAWM.

The following additional equipment performing an active SAWA/SAWM function is considered:

SAWA/SAWM flow instrument, SAWA/SAWM pump, FLEX generator, and SAWA throttle valve.

These components will be used at a remote location (outside Reactor Building) and have been evaluated for the environmental conditions applicable at those locations.

Ingress and Egress For locations outside the Reactor Building between 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br /> and 7 days when SAWA is being utilized, BFN performed a qualitative evaluation of equipment and deployment locations and confirmed they are protected by distance and/or buildings with substantial shielding to minimize dose rates. A quantitative evaluation of expected dose rates, AREVA document 51-9262174-003, Projected Dose Rate Contour Map of Shine from the HCVS Vent Line Extending Above Refueling Floor (BFNP), has been performed per HCVS-WP-02 and found the dose rates at deployment locations including ingress/egress paths are acceptable.

This ISE Open Item was closed as documented in Reference 12.

CNL-18-060 E-7

Browns Ferry Nuclear Plant HCVS Response Phase 2 ISE Open Items 3 Licensee to demonstrate how Equipment and Controls SAWA flow is capable to Plant instrumentation for SAWA that is qualified to perform its intended function RG 1.97 or equivalent is considered qualified for the for the sustained operating sustained operating period without further evaluation. The period under the expected following plant instruments are qualified to RG 1.97:

temperature and radiological DW Pressure Indicators, 1,2,3-PI-64-67B, and conditions.

Suppression Pool Level Indicators, 1,2,3-LI-64-159A.

Passive components that do not need to change state after initially establishing SAWA flow do not require evaluation beyond the first 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, at which time they are expected to be installed and ready for use to support SAWA/SAWM.

The following additional equipment performing an active SAWA/SAWM function is considered for temperature and radiation effects:

• SAWA/SAWM flow instrument,

• FLEX/SAWA pump,

• FLEX generator, and

• SAWA throttle valve.

Temperature The location of SAWA equipment and controls that are the same or similar as FLEX will be bounded by the FLEX evaluations for temperature.

Radiation For equipment locations outside the Reactor Building between 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br /> and 7 days when SAWA is being utilized, BFN performed a qualitative evaluation of equipment and deployment locations and confirmed they are protected by distance and/or buildings with substantial shielding to minimize dose rates. A quantitative evaluation of expected dose rates, AREVA document 51-9262174-003, Projected Dose Rate Contour Map of Shine from the HCVS Vent Line Extending Above Refueling Floor (BFNP), was performed per HCVS-WP-02, Sequences for HCVS Design and Method for Determining Radiological Dose from HCVS Piping, and found the dose rates at deployment locations are acceptable.

This ISE Open Item was closed as documented in Reference 12.

CNL-18-060 E-8

Browns Ferry Nuclear Plant HCVS Response Phase 2 ISE Open Items 4 Licensee to demonstrate that The wetwell vent has been designed and installed to meet containment failure as a result NEI 13-02 Revision 1 guidance which will ensure that it is of overpressure can be adequately sized to prevent containment overpressure prevented without a drywell under severe accident conditions.

vent during severe accident The SAWM strategy will ensure that the wetwell vent conditions. remains functional for the period of sustained operation.

BFN will follow the guidance (flow rate and timing) for SAWA/SAWM described in BWROG-TP-15-008, SAWA Timing, and BWROG-TP-15-011, SAWM Supporting Evaluations. The wetwell vent will be opened prior to exceeding the Primary Containment Pressure Limit value of 62 psig. Therefore, containment over pressurization is prevented without the need for a drywell vent.

This ISE Open Item was closed as documented in Reference 12.

5 Licensee to demonstrate how Using Figure 2.1.C from the combined Phase 1 and 2 OIP, the plant is bounded by the compare the reference plant parameters to the plant reference plant analysis that specific parameters.

shows the SAWM strategy is Reference Plant Browns Ferry successful in making it unlikely that a drywell vent is needed. Nuclear Plant Torus freeboard volume is Torus freeboard volume is 525,000 gallons 757,544 gallons SAWA flow is 500 gpm at SAWA flow is 500 gpm at 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> followed by 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> followed by 100 gpm from 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> to 100 gpm from 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> to 168 hours0.00194 days <br />0.0467 hours <br />2.777778e-4 weeks <br />6.3924e-5 months <br /> 168 hours0.00194 days <br />0.0467 hours <br />2.777778e-4 weeks <br />6.3924e-5 months <br /> The above parameters for BFN compared to the reference plant that determine success of the SAWM strategy demonstrate that the reference plant values are bounding. Therefore, the SAWM strategy implemented at BFN makes it unlikely that a DW vent is needed to prevent containment overpressure related failure.

This ISE Open Item was closed as documented in Reference 12.

6 Licensee to demonstrate that BFN utilizes the Harris Radio System to communicate there is adequate between the MCR and the operator at the FLEX pump.

communication between the This communication method is the same as accepted in MCR and the operator at the Order EA-12-049. These items will be powered and FLEX pump during severe remained powered using the same methods as evaluated accident conditions. under EA-12-049 and continued for the period of sustained operation.

This ISE Open Item was closed as documented in Reference 12.

CNL-18-060 E-9

MILESTONE SCHEDULE - ITEMS COMPLETE Milestone Target Activity Comments Completion Date Status Submit Phase 1 Overall June 2014 Complete Integrated Plan Submit Phase 2 Overall December 2015 Complete Integrated Plan Submit 6 Month Updates:

Update 1 December 2014 Complete Update 2 June 2015 Complete Update 3 December 2015 Complete Simultaneous with Phase 2 OIP Update 4 June 2016 Complete Update 5 December 2016 Complete Update 6 June 2017 Complete Update 7 December 2017 Complete Update 8 June 2018 Not Started Update 9 December 2018 Not Started Phase 1 Specific Milestones Phase 1 Modifications:

Hold preliminary/conceptual November 2014 Complete design meeting Unit 3 Design Engineering On- July 2017 Complete site/Complete Unit 3 Implementation Outage March 2018 Complete Unit 3 Walk Through April 2018 Complete Demonstration/Functional Test Phase 1 Procedure Changes Operations Procedure July 2016 Complete Changes Developed Site Specific Maintenance July 2016 Complete Procedure Developed Procedure Changes Active November 2016 Complete Phase 1 Training:

Training Complete September 2016 Complete Phase 1 Completion Unit 3 HCVS Implementation April 2018 Complete CNL-18-060 E-10

Phase 2 Specific Milestones Phase 2 Modifications:

Milestone Target Activity Comments Completion Date Status Hold preliminary/conceptual January 2017 Complete design meeting Unit 3 Design Engineering On- September 2017 Complete site/Complete Unit 3 Walk Through March 2018 Complete Demonstration/Functional Test Unit 3 Implementation Outage March 2018 Complete Phase 2 Procedure Changes Operations Procedure March 2018 Complete Changes Developed Site Specific Maintenance March 2018 Complete Procedure Developed Procedure Changes Active March 2018 Complete Phase 2 Training:

Training Complete March 2018 Complete Phase 2 Completion Unit 3 HCVS Implementation March 2018 Complete Submit Unit 3 Phase 1 and 2 May 2018 Complete Completion Report with this submittal ORDER EA-13-109 COMPLIANCE ELEMENTS

SUMMARY

The elements identified below for BFN, Unit 3, as well as the HCVS Phase 1 and Phase 2 OIP (Reference 5), the 6-Month Status Reports (References 3-9) and additional docketed correspondence demonstrate compliance with Order EA-13-109.

HCVS PHASE 1 AND PHASE 2 FUNCTIONAL REQUIREMENTS AND DESIGN FEATURES - COMPLETE The BFN, Unit 3, Phase 1 HCVS provides a vent path from the wetwell to remove decay heat, vent the containment atmosphere, and control containment pressure within acceptable limits. The Phase 1 HCVS will function for those accident conditions for which containment venting is relied upon to reduce the probability of containment failure, including accident sequences that result in the loss of active containment heat removal capability during an extended loss of alternating current power.

The BFN, Unit 3, Phase 2 HCVS provides a reliable containment venting strategy that makes it unlikely that the plant would need to vent from the containment drywell before alternative reliable containment heat removal and pressure control is reestablished. The BFN, Unit 3, Phase 2 HCVS strategies implement SAWA with SAWM as an alternative venting strategy. This strategy consists of the use of the Phase 1 wetwell vent and SAWA hardware to implement a water management strategy that will preserve the wetwell vent path until alternate reliable containment heat removal can be established.

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The BFN, Unit 3, Phase 1 and Phase 2 HCVS strategies are in compliance with Order EA-13-109. The modifications required to support the HCVS strategies for BFN, Unit 3, have been fully implemented in accordance with the station processes.

HCVS PHASE 1 AND PHASE 2 QUALITY STANDARDS - COMPLETE The design and operational considerations of the Phase 1 and Phase 2 HCVS installed at BFN, Unit 3, comply with the requirements specified in the Order and described in NEI 13-02, Revision 1, Industry Guidance for Compliance with Order EA-13-109. The Phase 1 and Phase 2 HCVS has been installed in accordance with the station design control process.

The Phase 1 and Phase 2 HCVS components, including piping, piping supports, containment isolation valves, containment isolation valve actuators and containment isolation valve position indication, have been designed consistent with the design basis of the plant. All other Phase 1 and Phase 2 HCVS components including electrical power supply, valve actuator pneumatic supply, and instrumentation have been designed for reliable and rugged performance that is capable of ensuring Phase 1 and Phase 2 HCVS functionality following a seismic event.

HCVS PHASE 1 AND PHASE 2 PROGRAMMATIC FEATURES - COMPLETE Storage of portable equipment for BFN, Unit 3, Phase 1 and Phase 2 HCVS use provides adequate protection from applicable site hazards, and identified paths and deployment areas will be accessible during all modes of operation and during severe accidents, as recommended in NEI 13-02, Revision 1, Section 6.1.2.

Training in the use of the Phase 1 and Phase 2 HCVS for BFN, Unit 3, has been completed in accordance with an accepted training process as recommended in NEI 13-02, Revision 1, Section 6.1.3.

Operating and maintenance procedures for BFN, Unit 3, have been developed and integrated with existing procedures to ensure safe operation of the Phase 1 and Phase 2 HCVS. Procedures have been verified and are available for use in accordance with the site procedure control program.

Site processes have been established to ensure the Phase 1 and Phase 2 HCVS is tested and maintained as recommended in NEI 13-02, Revision 1, Sections 6.1.2 and 6.2.

BFN, Unit 3, has completed validation in accordance with industry developed guidance to assure required tasks, manual actions, and decisions for HCVS strategies are feasible and may be executed within the constraints identified in the HCVS Phase 1 and Phase 2 OIP for Order EA-13-109 (Reference 5).

BFN, Unit 3, has completed evaluations to confirm accessibility, habitability, staffing sufficiency, and communication capability in accordance with NEI 13-02, Sections 4.2.2 and 4.2.3.

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REFERENCES:

The following references support the BFN, Unit 3, compliance with the requirements of Order EA-13-109:

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 (ML13143A321).

2. Letter from TVA to NRC, Tennessee Valley Authoritys 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 (Order Number EA-13-109), dated June 30, 2014 (ML14181B169)

3. Letter from TVA to NRC, Tennessee Valley Authority's Browns Ferry Nuclear Plant First 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), dated December 19, 2014 (ML14353A428)

4. Letter from TVA to NRC, Tennessee Valley Authority's Browns Ferry Nuclear Plant Second 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), dated June 29, 2015 (ML15181A338)

5. Letter from TVA to NRC, Tennessee Valley Authority's Browns Ferry Nuclear Plant Third Six-Month Status Report and Phase 1 and Phase 2 Overall Integrated Plan 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), dated December 29, 2015 (ML15365A554)

6. Letter from TVA to NRC Tennessee Valley Authoritys Browns Ferry Nuclear Plant Fourth 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), dated June 30, 2016 (ML16182A517)

7. Letter from TVA to NRC Tennessee Valley Authority Browns Ferry Nuclear Plants Fifth 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),dated December 22, 2016 (ML16357A577).

8. Letter from TVA to NRC Tennessee Valley Authority Browns Ferry Nuclear Plants 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), dated June 30, 2017 (ML17181A333).

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9. Letter from TVA to NRC Tennessee Valley Authority Browns Ferry Nuclear Plants Seventh 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), dated December 20, 2017 (ML17354A250).

10. Letter from NRC to TVA, Browns Ferry Nuclear Plant, Units 1, 2, and 3 - 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. MF4540, MF4541, and MF4542), dated February 11, 2015 (ML14356A362)

11. Letter from NRC to TVA, Browns Ferry Nuclear Plant, Units 1, 2, and 3 - Interim Staff Evaluation Relating to Overall Integrated Plan in Response to Phase 2 of Order EA-13-109 (Severe Accident Capable Hardened Vents) (CAC Nos. MF4540, MF4541, and MF4542), dated September 6, 2016 (ML16244A762)

12. Letter from NRC to TVA, Browns Ferry Nuclear Plant, Units 1, 2, and 3 - Report for the Audit of Licensee Responses to Interim Staff Evaluations Open Items Related to NRC Order EA-13-109 To Modify Licenses With Regard To Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions (CAC Nos. MF4540, MF4541, and MF4542; EPID L-2014-JLD-0044), dated February 21, 2018 (ML18038B606)

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