ML22119A116
| ML22119A116 | |
| Person / Time | |
|---|---|
| Issue date: | 04/27/2022 |
| From: | Meena Khanna NRC/NRR/DRA |
| To: | |
| Zoulis A | |
| References | |
| Download: ML22119A116 (36) | |
Text
Risk Management Committee Meeting PWROG Meeting: April 27, 2022 Meena Khanna, Deputy Director Division of Risk Assessment Office of Nuclear Reactor Regulation 1
Introduction 2
Meena Khanna, Deputy Director, Division of Risk Assessment
AGENDA High Energy Arcing Faults (HEAF)
TSTF-505 Lessons Learned 3
Risk Informed Process for Evaluations (RIPE)
PRA Configuration Control RI Diversity For Common Cause Failure in Digital I&C Systems Seismic Update RG 1.200 Update Risk-Informed Categorization and Treatment of Electrical and Electronic Equipment (IEEE)
4 Risk-Informed Process for Evaluations (RIPE)
Antonios Zoulis, Chief, PRA Oversight Branch
5 IDP PRA RIPE (using existing regulations)
Integrated Decision-making Panel (IDP) Reviews Key Engineering Principles Demonstrated Probabilistic Risk Assessment Acceptability RIPE Leverages Previous Risk-Informed Initiatives
6 1st Application Submitted Under RIPE
- First RIPE exemption request submitted by APS for review January 2021
- Exemption from 10 CFR 50.62(c)(1) (ATWS Rule) for Palo Verde
- The ATWS Rule includes the following three requirements in 50.62(c): (1) the diverse auxiliary feedwater actuation, (2) diverse turbine trip, (3) diverse reactor scram as well as the existing safety related actuation of AFS (AFAS) and the reactor protection system reactor/turbine trip under the conditions of an ATWS
- The RIPE submittal requested a partial exemption to eliminate the Diverse Auxiliary Feedwater Actuation System (DAFAS) requirement only
- Acceptance review did require request for clarifying information
- SE completed and issued on March 23, 2022, within 81/2 weeks
- PVNGS RIPE Exemption SE (ML22054A005)
- PVNGS RIPE Exemption (ML22054A006)
7 Schedule & Resources for Palo Verde Exemption (RIPE)
Milestone RPS Date*
Actual Date Remarks Application declared in ADAMS 1/21/22 1/18/22 Application received on 1/14/22 (COB) (ML22014A415)
Staff sends acceptance review results to licensee 2/7/22 1/31/22 ML22032A031 Staff issues final RCIs to the licensee 2/14/22 2/10/22 ML22035A330 Licensee submits to staff its response to RCIs 2/28/22 2/22/22 ML22053A212 DRA/APOB submits SE input to DORL 3/4/22 2/22/22 DORL provides SE to OGC for NLO/concurrence 3/18/22 2/23/22 OGC completes review 4/1/22 3/17/22 DORL issues exemption 4/18/22 03/23/22 Total hours ~ 97
8 Preliminary Lessons-Learned Lessons Learned Revise Internal Staff Guidance Model SE Internal RIDM Workshops IDP Observation and Results
9 Future Work
- Expand RIPE to allow Technical Specifications changes - guidance is expected to be issued by June 2022
- Continue working with the PWROG on RIPE-G generic process for topical reports
-Observe the GAET process
-Plan for future public meetings
- Any other applications?
10 Potential Benefits
- Focus NRC and licensee resources on the most safety significant issues
- Address low safety significance compliance issues in an efficient and predictable manner consistent with NRC's Principles of Good Regulation
- Leverage existing regulations and risk insights
- Incentivize the further development and use of probabilistic risk assessment models and applications
11 Update on Aluminum High Energy Arcing Fault (HEAF) LIC-504 Assessment Reinaldo Rodriguez, PRA Oversight Branch
12 Status Update
- Received outstanding support from licensees to help NRC improve realism of analysis supporting the LIC-504 evaluation
- Collaborating with reference plants to estimate realistic risk estimates associated with the new PRA HEAF method
- Conduct sensitivity studies to augment the analysis making it more generically applicable
13 Preliminary Insights
- RES/EPRI working group is in the process of addressing this issue
- Based on staff assessments and the site visits completed to date, the HEAF frequency for many sources has decreased; however, due to possible additional targets for bus ducts, we may see some risk increases
- Its too early to tell if any insights would help shape future inspections
14 Next Steps Complete documenting risk-informed insights from operational experience and information obtained from reference plant site visits. (June 2022)
Issue LIC-504 team recommendations on any regulatory actions, as needed, based on results from the LIC-504 assessment (July 2022)
Complete supporting technical documents (December 2022)
15 LIC-504 Team Recommendations
- LIC-504 team recommendations will be informed by results of staff analyses and staffs review of operating experience
-Reference plant site visits enable staff to enhance realism of LIC-504 analyses
16 PRA Configuration Control Antonios Zoulis, Chief, PRA Oversight Branch Edgardo Torres, PRA Oversight Branch
17 PRA Configuration Control Update
- To date, NRC has held two public meetings:
-PRA Acceptability Framework (February 2)
-Information Gathering & Guidance Development Effort (Tabletops) (April 5)
- NEI Sponsored PRA Configuration Control Workshop (April 22)
18 Whats Next?
ROP Change Control Process Refine guidance and share PRA Acceptability Framework recom-mendations for feedback Conduct tabletops Finalize Information Gathering Needs
19 Conducted 2 public meetings February &
March 2022 Identify and select eight facilities for table-tops/
site visits May 2022 Begin table-tops/site visits at facilities July 2022 Complete assessment of information gathered via site visits and guidance development effort December 2022 Brief NRR management on final recommendations of effort March 2023 Discuss findings at ROP monthly public meeting April 2023 Discuss any feedback at ROP Monthly public meeting May 2023 Revise Tier 2 inspection guidance December 2023 Whats Next?
Enter ROP change control process February 2023
20 IEEE 1819-2016 Robert Pascarelli, Chief, PRA Licensing Branch A
21 IEEE 1819-2016 Background
Purpose:
provides methods to categorize electrical and electronic components using a risk-informed process and provides the recommended treatment of categorized components commensurate with their safety significance
- Goal: Seek endorsement by NRC for applicability to electrical and electronic systems and components only
- Public meeting was held on March 16, 2022, to discuss staffs consideration of IEEE 1819-2016
22 IEEE 1819-2016 Current Status
- Public meeting held with representatives from the nuclear industry, including the Institute of Electrical and Electronics Engineers (IEEE) - Nuclear Power Engineering Committee (NPEC)
- Purpose of the meeting was to discuss the NRC staffs consideration of IEEE Std 1819-2016
- Multiple presentations given by NRC, NEI and IEEE. IEEE requested insights from other groups and participation in the development of the next revision of IEEE Std. 1819
- Meeting Summary issued April 4, 2022 (ML22091A227)
23 TSTF-505 Lessons Learned Robert Pascarelli, Chief, PRA Licensing Branch A
24 TSTF - 505 Background
- Allows licensees to create and manage a TS configuration risk management program to establish Risk-Informed Completion Times (RICTs) for LCO Allowed Outage Times (AOTs)
- Adds new program in TS "Administrative Controls" entitled the "Risk-Informed Completion Time Program"
- Provides list of STS Conditions in scope, model license amendment application and model safety evaluation
25 TSTF-505 Background/Current Status
- Revision 2 addressed issues identified in Revision 1 (suspended in November 2016)
- Addresses loss of function conditions
- Additional treatment of Common Cause Failure (CCF)
- Industry has submitted 27 applications to adopt RITS Initiative 4b
- NRC staff has approved 17 applications
- Currently reviewing the remaining 10 applications and Anticipate receiving an additional 7 applications by the end of FY 2022
26 TSTF-505 Best Practices
- Pre-submittal meetings are helpful to staff to understand licensees strategies and goals for LAR
- Allows for early dialogue/clarifications to reduce acceptance review pitfalls
- Reviewing previous submittals and following best practices will facilitate efficient NRC review
- Pro-active measures can also help licensee anticipate and address common RAIs
- Leveraging F&O closure process is a valuable tool to increase efficiency of review process
- Audit preparation facilitates quality NRC review on complex topics
27 Risk-Informing Evaluations of Common Cause Failures in Digital I&C Systems Shilp Vasavada, Acting Chief, PRA Licensing Branch C
28 Risk-Informing Evaluations of Common Cause Failure in Digital I&C Systems This Photo by Unknown Author is licensed under CC BY-SA-NC
- Policy Expansion - SECY under development
- High internal and external interest
- Current policy will remain available
- Aggressive schedule
- Transmittal of SECY to Commission by August 2022
- Five principles of risk-informed decision-making
29 Risk-Informing Evaluations of Common Cause Failure in Digital I&C Systems (Contd)
- Guidance development
- Following issuance of Staff Requirements Memorandum (SRM) on SECY
- Intent is to leverage existing risk-informed decision-making and PRA quality guidance
- Considering options to avoid software reliability determination This Photo by Unknown Author is licensed under CC BY-NC-ND
30 Recent Seismic Hazard Related Activities at NRC Shilp Vasavada, Acting Chief, PRA Licensing Branch C
31 Recent Seismic Hazard Related Activities at NRC
- NUREG/KM-0017 and RIL2021-15 provide updated information for site amplification
- Recent letter provides additional information and timeline(ML21312A077)
- NRCs seismic hazard subject matter experts are preparing for a public meeting in early May
Update on Next Revision to RG 1.200 32 Sunil Weerakkody, Senior Level Advisor, Division of Risk Assessment
33 Background
Summary of Changes in Revision 3 of RG 1.200 Endorsed Nuclear Energy Institute (NEI) 17-07, Revision 2.
Endorsed, with staff exceptions and clarifications, requirements in ASME/ANS RA-S Case 1 for ASME/ANS RA-Sb-2013 Standard for Level 1/LERF PRA of Nuclear Power Plant Applications.
Endorsed several sections of the Pressurized Water Reactor Owners Group (PWROG), PWROG-19027-NP, Revision 2.
Enhanced guidance related to key assumptions and sources of uncertainty Provided a glossary of key terms Provided a list of hazards to be considered in the development and use of PRA.
Modified the staff's previous endorsement of ASME/ANS RA-Sa-2009 in RG 1.200, Revision 2, to reflect endorsement of terms and their definitions derived from PWROG-19027-NP, Revision 2.
34 Scope and Schedule for Next Revision (i.e., Revision 4) to RG 1.200
- Schedule and scope of the next revision will vary depending on needs and priorities of NRC and the stakeholders.
- Scope of documents to be endorsed will include the next edition of the Level 1/LERF PRA standard (ASME/ANS RA-S-1.1-2022; to be published May 2022)
- Other items that will be considered for inclusion in the next technical revision of RG 1.200 are:
- Level 2 LWR PRA standard (ASME/ANS RA-S-1.2) (est. publication ~Feb 2023)
- ALWR PRA standard (ASME/ANS RA-S-1.5) (est. publication ~Nov 2023)
- LPSD PRA standard (2014 trial use std., consensus std. by ~Oct 2023)
- Level 3 PRA standard (2017 trial use std., consensus std. by ~Jan 2023)
- Multi-Unit PRA standard (est. publication ~Nov 2023)
- Public meetings will be used to identify and communicate scope and schedule.
35 Regulatory Implications Revisions to RGs disseminate the staff positions that reflect the current staff views.
NRC staff does not intend to use the guidance in this regulatory guide to support NRC staff actions in a manner that would constitute backfitting (10 CFR 50.109 & NRC Management Directive 8.4).
The staff does not intend to use the guidance to support NRC staff actions in a manner that constitutes Forward Fitting (NRC Management Directive 8.4)
Nor does the NRC staff intend to use revised guidance to affect the issue finality of an approval under 10 CFR Part 52, Licenses, Certifications, and Approvals for Nuclear Power Plants.
36 Questions