ML21250A301
| ML21250A301 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 09/07/2021 |
| From: | Tennessee Valley Authority |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| Download: ML21250A301 (13) | |
Text
License Amendment Request Revise Browns Ferry Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b September 7, 2021
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
- Applicable in Modes 1 and 2
- No loss of function consistent with template
- New TS 5.5 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 BFN 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 4
TSTF-505 Variations (continued)
Four technical variations are being taken BFN Instrumentation RAs that are not in STS meet the criteria for applying a RICT BFN RHR suppression pool cooling system differs from STS reference plant BFN RHR Service Water system differs from STS reference plant Site-specific Electrical Distribution RAs that are not in STS due to shared system capability which meet the criteria for applying a RICT 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 4 RAs that will allow an RICT to be applied to Six administrative variations Consistent approach proposed by Callaway Deletion of one-time historical change to BFN Unit 2 TS 3.5.1 6
PRA Technical Acceptability Internal Events including Internal Flooding
- Finding Closure Review Performed Using Appendix X Process
- No Open Internal Events/Internal Flooding Finding Level F&Os Fire
- 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-Sb-2013 (Code Case 1) with NRC Conditions (ML18017A963)
- 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
- Screening performed based on approved BFN 10 CFR 50.69 LAR (as updated for the as-built, as-operated plant) 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 Analysis Software
- Incorporates RICT Calculation Based on CDF and LERF for Units 1, 2, and 3 with maximum 30-day backstop 9
Schedule
- Projected submittal in November 2021 with a requested approval within one year
- A 180-day implementation period is proposed 10
Summary
- RICT process will follow NEI 06-09-A
Questions/
Comments
???
12