ML22094A198
| ML22094A198 | |
| Person / Time | |
|---|---|
| Issue date: | 04/05/2022 |
| From: | Edgardo Torres NRC/NRR/DRA/APOB |
| To: | |
| Edgardo Torres | |
| References | |
| Download: ML22094A198 (16) | |
Text
1 APRIL 5, 2022 Second PRA Configuration Control Public Workshop DISCLAIMER: THIS MEETING WILL BE RECORDED Edgardo Torres Reliability and Risk Analyst Office of Nuclear Reactor Regulation Division of Risk Assessment PRA Oversight Branch
2 Purpose/Agenda
- Key Messages
- February Public Workshop Take-aways
- Discuss Information Gathering in Support of Voluntary Tabletops and Guidance Development Update
- Q&A/Feedback Session
3 Key Messages
- The existing oversight process is adequate to ensure appropriate implementation of risk-informed programs
- However, we believe that there is a current gap in the oversight of PRA Configuration Control
- We are taking a Balanced Approach to ensure continued PRA acceptability and adherence to the regulatory guidance documents, while maintaining a risk-informed performance-based approach
- NRCs enhancement to the oversight framework will be informed by continued interactions with industry and the public
4 Key Messages (Contd.)
- NRC information requests to support the voluntary site tabletops will be from licensees existing, readily available information
- Information will be used to support different aspects of enhanced guidance development to ensure NRCs ability to:
- Independently verify licensees PRA configuration control program
- Conduct performance-based risk informed sampling
- Confirm PRA represents as-built as-operated plant
- Develop a balanced approach with appropriate level-of-effort and resources
5 February Public Workshop Take-away
- How is the PRA Configuration Control process going to provide feedback to the new version of the standard that has some improvement and additional elements of clarification in the PRA Configuration Control technical elements?
- Once the staff has completed this effort, the NRC plans to provide the ASME Committee with any lessons learned
- The NRC will consider potential process improvements, as appropriate, for consideration in a future revision of RG 1.200
6 February Public Workshop Take-away (Contd.)
- Is Section 1.5 of the PRA consensus standard something worth a different schedule of endorsement once some of this feedback and observations are built and some feedback from the NRC can be developed?
- Since we are in the early stages of the process, NRC will evaluate the appropriate course of action in this context considering resources, other activities, and anticipated completion schedules
7 Information Gathering and Guidance Development -
Voluntary Tabletops
- Coordination with NEI for voluntary tabletops:
- Two with SFCP
- Two with SFCP and 50.69
- At least two NFPA 805
- Considerations:
- One facility per licensee
- Balance facilities across the four regions (two per region)
- Information gathering will be focused on plant's implementation of Configuration Controls for approved risk-informed initiatives
- NRC will contact non-NEI members
8 Information Gathering and Guidance Development (Contd.)
- Purpose of the tabletops are to help focus and develop future inspection guidance
- Voluntary Information request in support of NRC tabletops
- Procedures:
- PRA Configuration Control per ASME/ANS RA-Sa-2009
- Input Monitoring/Control
- Maintenance/Upgrade
- Pending Changes (Cumulative Risk); Information request after procedure review.
- PRA Computer Code Configuration Control; Information request after procedure review.
- Database control (Documentation)
9 Information Gathering and Guidance Development (Contd.)
- Procedures:
- Configuration control interface with Surveillance Frequency Control Program (SFCP), 10 CFR 50.69 and Risk-Informed Completion Time (RICT).
- NFPA 805 internal fire Configuration Control if different from PRA Configuration Control
- Design and Engineering Changes Control
- EOP, AOP and Standard Operating Procedures change control
- Internal and Industry Operating Experience program
10 Information Gathering and Guidance Development (Contd.)
- PRA Notebooks - Staff to identify PRA-specific documentation based upon targeted review of licensee applied risk-informed applications and scope of PRA changes
- Licensed operator lesson plans for top 10 risk-significant systems based on risk achievement worth (RAW) and Fussel-Vesely (FV) for each approved hazard group model
- Copies of the last two PRA model-of-record (MOR) updates CDF awareness summaries to site management or an initiating event percent distribution chart
11 Information Gathering and Guidance Development (Contd.)
- List of components and operator actions basic events for CDF based on RAW and FV from the current and prior MOR update. Provide similar information for additional approved hazard group models. Include the below importance measures.
- FV
- RAW
- Birnbaum (BI)
- List of components and operator actions basic events for LERF based on RAW and FV from the current and prior MOR update. Provide similar information for additional approved hazard group models. Include the below importance measures.
- FV
- RAW
- BI
12 Information Gathering and Guidance Development (Contd.)
- List of top 20 baseline dominant sequences and associated top 50 cut sets from current and prior MOR. Provide similar information for additional approved hazard group models.
- Basic events nomenclature information to understand association to components/human events used in PRA
- List of PRA Configuration Control updates (maintenance/upgrade) evaluations or model change log/tracking changes software, from the prior through current MOR update period for all approved hazard group models
13 Information Gathering and Guidance Development (Contd.)
- Pending changes from model change logs/tracking change software to the current MOR and additional approved hazard group models.
- List of high priority (i.e., I, II, III) condition reports (CRs) or action request (AR) from the prior through current MOR update.
14 Information Gathering and Guidance Development (Contd.)
- List of changes from the following areas from the prior through current MOR update:
- Design/Engineering changes (Fully/Partially Installed)
- Tracking and control of systems, structures, and components (SSCs) unavailability hours data for top 50 risk-significant components, based on FV and RAW, per approved hazard group
- Tracking and control of SSC reliability data for top 50 risk-significant components, based on FV and RAW, per approved hazard group
- Plant and industry operating experience from the prior through current MOR update
15 Path Forward
- Coordination and preparations for site-visits/tabletops (April/May 2022)
- Commence site visits/tabletops (May 2022)
- Complete preliminary report with observations from site visits, etc. (December 2022)
- Conduct public meeting to discuss observations and recommendations for feedback (February 2023)
16 Feedback and Q&A Session