ML24346A071

December 17, 2024, Meeting Slides - License Amendment Request Revise Watts Bar Technical Specifications to Adopt Risk Informed Completion Times TSTF-505,Rev. 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4 EPID L-20

ML24346A071
Person / Time
Site:	Watts Bar
Issue date:	12/17/2024
From:	Tennessee Valley Authority
To:	Kimberly Green NRC/NRR/DORL/LPL2-2
Green K
References
EPID L-2024--LRM-0141
Download: ML24346A071 (1)

Text

License Amendment Request Revise Watts Bar Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b December 17, 2024

Agenda

• Describe future license amendment request (LAR)

Scope of the Request Variations from TSTF-505 PRA Models and CRMP Summary

• LAR Schedule

• Summary

• Questions/Comments?

2

Scope of the Request

• LAR is based on TSTF-505, Revision 2, and NEI 06-09, Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS)

Guidelines

• RICTs apply to 54 WBN LCOs

- Applicable in Modes 1 and 2

- No loss of function consistent with template

• New TS 5.7 program called the Risk Informed Completion Time Program

• LAR informed by approved precedent and those currently under review

• Includes adoption of TSTF-439, Revision 2, Eliminate Second Completion Times Limiting Time From Discovery of Failure to Meet an LCO 3

TSTF-505 Variations Several types of administrative variations are taken Required Actions (RAs) with different numbering and slightly different wording with same intent TSTF-505 RAs that Watts Bar TS do not have Instrumentation RAs invoked for different Functions or wording that a RICT applies to RICTs not applied since Additional Justifications werent met (e.g., not having a Shutdown PRA), or loss of function could not be confirmed Corrections to obvious minor traveler errors Different Conditions nested with the new default Conditions of TS 3.3.1 and 3.3.2 4

TSTF-505 Variations (continued)

Five technical variations are being taken Instrumentation RAs that are not in STS meet the criteria for applying a RICT RHR spray trains are not included in STS but are RICT eligible DG DC battery chargers are not included in STS, but are RICT eligible DG DC trains are not included in STS, but are RICT eligible AC electrical power distribution subsystems inoperable due to AC shutdown board inoperability is not a Condition in STS, but is RICT eligible 5

Other changes TSTF-439 is included Traveler is cited as prerequisite for applying RICT to RAs with second completion times.

Technical justification is incorporated as a different stand-alone section of the LAR Affects 8 RAs that will allow an RICT to be applied to Seven administrative variations of inconsequential nature Consistent approach used with the Browns Ferry RICT LAR 6

PRA Technical Acceptability Internal Events including Internal Flooding

• Peer Reviewed Using NEI 05-04 Process Against ASME/ANS RA-Sa-2009 (Parts 2 and 3) with RG 1.200 Rev 2 Exceptions

• Finding Closure Review Performed Using Appendix X Process

• No Open Internal Events/Internal Flooding Finding Level F&Os Fire

• Peer Reviewed Using NEI 07-12 Process Against ASME/ANS RA-Sa-2009 (Part 4) with RG 1.200 Rev 2 Exceptions

• Finding Closure Review Performed Using Appendix X Process

• No Open Fire PRA Finding Level F&Os 7

PRA Technical Acceptability (continued)

Seismic

• Peer Reviewed Using NEI 12-13 Process Against ASME/ANS RA-Sa-2009 with RG 1.200 Rev 2 Exceptions

• Finding Closure Review Performed Using Appendix X Process

• No Open Seismic PRA Finding Level F&Os Other External Hazards

• All Other External Hazards Screened Out in accordance with ASME/ANS RA-Sa-2009 (Part 6)

• Screening performed based on approved WBN 10 CFR 50.69 LAR (as updated for the as-built, as-operated plant)

(ML18334A363) 8

RICT Program Real-Time Model A Real-Time Risk Model similar to existing Maintenance Rule a(4) Configuration Risk Management Program

• Incorporates Internal Events, Internal Flooding, Fire and Seismic into a One-Top Multi-Hazard Model

• Uses EPRI Phoenix Risk Monitor Software

• Incorporates RICT Calculation Based on CDF and LERF for Units 1, and 2 with maximum 30-day backstop 9

Schedule

• Projected submittal in December 2024 with a requested approval within one year

• A 180-day implementation period is proposed 10

Summary

• TSTF-505 LAR is scheduled to be submitted in December 2024 with approval requested in one year

• LAR is consistent with TSTF-505 Model Application

• RICT process will follow NEI 06-09-A

• PRA is technically acceptable for the RICT Application 11

Questions/

Comments

???

12