ML22089A093
| ML22089A093 | |
| Person / Time | |
|---|---|
| Issue date: | 04/21/2022 |
| From: | Lois James Licensing Processes Branch |
| To: | Richard Chang Licensing Processes Branch |
| James L | |
| References | |
| Download: ML22089A093 (7) | |
Text
April 21, 2022 MEMORANDUM TO:
Richard Chang, Chief Licensing Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation FROM:
Lois M. James, Senior Project Manager /RA/
Licensing Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
SUBJECT:
MEETING
SUMMARY
- MARCH 4, 2022, MEETING ON STAFF PERSPECTIVES ON RISK-INFORMED MODIFICATION OF INSERVICE INSPECTION PROGRAM On March 4, 2022, the U.S. Nuclear Commission (NRC) staff met with representatives from the Electric Power Research Institute (EPRI) to discuss the staffs perspective on risk-informed modification of the inservice inspection program. The meeting summary is provided as and the list of attendees is provided as Enclosure 2. The meeting notice is dated February 22, 2022, and the meeting agenda is available in the Agencywide Documents and Access Management System at Accession No. ML22053A171. The NRC staff presentation slides are available in ADAMS at Accession No. ML22060A277.
If you have any questions or comments, please contact me via e-mail at Lois.James@nrc.gov.
Enclosures:
- 1. Meeting Summary
- 2. List of Attendees cc w/enclosures:
CONTACT: Lois M. James, NRR/DORL/LLPB 301-415-3306
U.S. Nuclear Regulatory Commission Public Meeting Summary
Title:
Staff Perspectives on Risk-Informed Modification of the Inservice Inspection (ISI)
Program Date of Meeting: March 4, 2022, 1:00 pm - 2:30 pm Location: Webinar Type of Meeting: This was an Observation Meeting in which attendees had an opportunity to observe the U.S. Nuclear Regulatory Commission (NRC) performing its regulatory function or discussing regulatory issues. Attendees had an opportunity to ask questions of the NRC staff or make comments about the issues discussed following the business portion of the meeting; however, the NRC was not actively soliciting comments toward regulatory decisions at this meeting.
Purpose of the Meeting: To communicate the NRC staff perspectives on risk-informed modification of the ISI program.
General Details: The NRC staff held a public, observational meeting with the Electric Power Research Institute (EPRI) to communicate the staff perspectives on risk-informed modification of the ISI program. The meeting began at 1:00 pm and ended 2:30 pm. There were 26 NRC staff members, 4 EPRI representatives, 21 members of industry, and 22 members of the public or individuals who did not identify their affiliation. The meeting began with introductions of the NRC staff, EPRI representatives, and industry members.
Summary of Meeting: The NRC staff began the meeting by noting an increase in ISI submittals that are explicitly or implicitly risk informed. Further, the staff noted that many of these submittals contain novel applications of probabilistic modeling or other risk-based arguments. The staff is reviewing these risk-informed applications, whether explicit or implicit, on their merits under the risk-informed decisionmaking framework.
To ensure a common understanding, the staff described the principles of risk-informed decisionmaking:
- 1. current regulations must be met
- 2. defense in depth consistency
- 3. maintenance of safety margins
- 4. risk-informed analysis
- 5. performance monitoring All five of the principles need to be addressed. The NRC staff provided an example in that probabilistic fracture mechanics (PFM) analyses may support Principle 3, maintenance of safety margin, and Principle 4, risk-informed analysis, but does not address Principle 5, performance monitoring. However, PFM analyses allow for more weight to be given to Principle 4, risk-informed analysis, when combined with adequate Principle 5, performance monitoring.
In discussing Principle 5, the NRC staff explained that performance monitoring provides:
- 1. Direct evidence of the presence and extent of degradation if present
- 2. Validation and confirmation of the adequacy of analyses
- 3. Timely methods to detect novel or unexpected degradation Industry members expressed concern about the 20-year limit and why the NRC staff appears to be deviating from the pilot plants amendments that have been approved.
Regarding the deviating from the pilot plants amendments, the NRC staff explained that not all the subsequent applications submitted have been consistent with the pilot plants application and these inconsistencies have resulted in internal conversations and reconsideration of the path forward. Specifically, the NRC staff acknowledges that it was not as clear as it should have been in the safety evaluations for the pilot plants amendments and that it did not fully address the implications of the decisions as well as it should. When it comes to approving ISI extensions, the NRC staff stated that the three objectives that need to be met for performance monitoring are:
- 1. direct reading,
- 2. to validate basis analysis, and
- 3. it has to be timely.
The NRC staff further stated that performance monitoring does not have to be any specific testing. Rather the testing must be justified as supporting the three objectives listed above.
Regarding the 20-year extension limit, the NRC staff stated that any year is arbitrary. The length of the extension depends on many things, such as the safety significance of the component and the environment of the component. The NRC staff chose 20 years as a judicial, prudent, first step. A longer time can be requested but such a request must have a judicial, prudent, justification which should include an appropriate level of performance monitoring.
The NRC staff restated that two key aspects of performance monitoring are to make sure that basis analysis and calculations remains valid and to see if there are any new or unknown degradations.
Industry members asked if it would have been better to have submitted a topical report (TR).
The NRC staff stated that a TR would have been better. When reviewing a TR, the staff is looking on a general level about what level of sampling is appropriate. The NRC staff has found several levels of sampling acceptable, and sampling is a powerful tool and justification. When reviewing plant specific ISI extensions, the sampling aspects are limited.
The NRC staff ended the meeting by reiterating the practical takeaways:
- 1. Extension of ISI intervals to 20 years may be justified as a prudent first step in optimization of ISI intervals
- 2. Coordination of inspections over extended ISI intervals is prudent to ensure appropriate monitoring and trending of the subject components Monitor for potential unknown degradation mechanisms
Form a basis for potential future applications to further extension Public Participation Themes:
No member of the public spoke on the webinar and no public meeting feedback forms were received.
Related Documents:
- 1. Meeting notice and agenda - ADAMS Accession No. ML22053A171
- 2. NRC slide presentation - ADAMS Accession No. ML22060A277
U.S. Nuclear Regulatory Commission Public Meeting Participants
Title:
Staff Perspectives on Risk-Informed Modification of Inservice Inspection (ISI) Program Date of Meeting: March 4, 2022, 1:00 pm - 2:30 pm U.S. Nuclear Regulatory Commission Participants Name Affiliation Allen Hiser U.S. Nuclear Regulatory Commission (NRC)/Office of Nuclear Reactor Regulation (NRR)/Division of New and Renewed Licenses (DNRL)
David Rudland NRC/NRR/DNRL Brian Smith NRC/NRR/DNRL Bernie Thomas NRC/NRR/DNRL Bill Rogers NRC/NRR/DNRL/License Renewal Projects Branch Isaac Anchondo-Lopez NRC/NRR/DNRL/Vessels and Internals Branch (NVIB)
Michael Benson NRC/NRR/DNRL/NVIB Angie Buford NRC/NRR/DNRL/NVIB David Dijamco NRC/NRR/DNRL/NVIB Carolyn Fairbanks NRC/NRR/DNRL/NVIB Matthew Mitchell NRC/NRR/DNRL/NVIB John Tsao NRC/NRR/DNRL/NVIB Dan Widrevitz NRC/NRR/DNRL/NVIB On Yee NRC/NRR/DNRL/NVIB Undine Shoop NRC/NRR/Division of Operating Reactor Licensing (DORL)/Integrated Program Management and BDB Lois James NRC/NRR/DORL/Licensing Projects Branch Brent Ballard NRC/NRR/DORL/Plant Licensing Branch I (LPL1)
James Danna NRC/NRR/DORL/LPL1 James Kim NRC/NRR/DORL/LPL1 Audrey Klett NRC/NRR/DORL/LPL1 Jason Paige NRC/NRR/DORL/LPL1 Justin Poole NRC/NRR/DORL/LPL1 V. Sreenivas NRC/NRR/DORL/LPL1 Ed Miller NRC/NRR/DORL/Plant Licensing Branch II-1 Blake Purnell NRC/NRR/DORL/Plant Licensing Branch III (LPL3)
Joel Wiebe NRC/NRR/DORL/LPL3 Industry Participants Name Affiliation John Conly Certrec Corporation Roy Linthicum Constellation Nuclear Thomas Loomis Constellation Nuclear Heather Malikowski Constellation Nuclear Sailaja Mokkapati Constellation Nuclear Romit Patel Constellation Nuclear Diane Render Constellation Nuclear Veena Gubbi DEP
Industry Participants Name Affiliation Brian Anderson Duke Energy Lee Grzeck Duke Energy Austin Charles Keller Duke Energy Mark Pyne Duke Energy Victoria Anderson Electric Power Research Institute (EPRI)
James Cirilli EPRI Robert Grizzi EPRI DJ Shim EPRI Kevin Hall (Iddeal)
Iddeal Solutions Scott Kulat Inservice Engineering Donna Slivon NextEra Energy Gary Lofthus Southern Nuclear Company Corey Thomas Southern Nuclear Company Kevin Wong Structural Integrity Associates, Inc.
Marisa Garcia Heras Tecnatom, Spain Daniel Lamond True North Consulting Richard Deopere Xcel Energy Members of the Public Name Kevin Allen Jerri Byers Sarah Champion Steve Chengelis Scott Chesworth Nat Chofie Rob Choromokos Dilip Dehia Hein Do Adam Keyser Matthew King Norman Eugene Kunkel Annie Mayer Steve Mays Kathleen Nevins Nathan Palm Deann Raleigh Chet Austin Sigmon Carroll Trull Mo Uddin Two individuals did not provide a name
Meeting Summary - ML22089A093 Meeting Notice and Agenda - ML22053A171 NRC Slide Presentation - ML22060A277
- via e-mail NRR-106 OFFICE DORL/LLPB/PM DORL/LLPB/LA DNRL/NVIB/BC DORL/LLPB/BC NAME LJames*
DHarrison ABuford RChang DATE 3/28/2022 3/31/2022 4/8/2022 4/21/2022 OFFICE DORL/LLPB/PM NAME LJames DATE 4/21/2022