Past Public Meetings

The Diablo Canyon Independent Safety Committee Notice of Public Meeting

  THE DIABLO CANYON INDEPENDENT SAFETY COMMITTEE
(https://www.dcisc.org)
    NOTICE OF PUBLIC MEETING

NOTICE IS HEREBY GIVEN that on October 9-10, 2024, at the Avila Lighthouse Suites Point San Luis Conference Facility located at First & San Francisco Streets, Avila Beach, California, a public meeting will be held by the Diablo Canyon Independent Safety Committee (DCISC) in five separate sessions, at the times indicated, to consider the following matters.You may also participate in the DCISC's public meeting in real-time by accessing the Zoom webinar meeting via the weblink or meeting ID given below or by using any of the phone numbers provided. Webinar attendees can make oral comments or ask questions of the Committee Members during the webinar meeting by using the "Raise Your Hand" feature or by pressing *9 on your telephone keypad if joining by telephone only. If you are unable to attend or participate in real-time, you may email to dcsafety@dcisc.org with the subject line "Public Comment Agenda Item #___" (insert the item number relevant to your comment) or "Public Comment - Non Agenda Item." Comments will be reviewed and distributed before the meeting if received by noon on Tuesday, October 8, 2024. Comments received after that will be addressed during the item or at the end of the meeting. Each session will include comments by the Committee Members and an opportunity for members of the public to address remarks to the Committee.

Zoom Webinar Meeting ID: 820 9678 8325
Please click the link below to join the webinar
https://us02web.zoom.us/j/82096788325
Zoom Webinar Meeting Telephone Only Participation: One tap mobile: +16699006833,,82096788325# US (San  Jose), +14086380968, 82096788325# US (San Jose);     Dial(for higher quality, dial a number based on your current location):  +1 669 900 6833 US (San Jose), +1 408 638 0968 US (San Jose), +1 669 444 9171 US, +1 719 359 4580 US. +1 253 205 0468 US, +1 253 215 8782 US (Tacoma).+1 346 248 7799 US (Houston). +1 646 931 3860 US, +1 689 278 1000 US, +1 301 715 8592 US (Washington DC), +1 305 224 1968 US, +1 309 205 3325 US, +1 312 626 6799 US (Chicago),+1 360 209 5623 US, +1 386 347 5053 US, +1 507 473 4847 US, +1 564 217 2000 US, +1 646 876 9923 US (New York).

1.         Morning Session - (10/09/2024) – 9:00 a.m.  Introduction of Committee Member Dr. Najmedin Meshkati, the appointee of the Chair of the California Energy Commission to the DCISC; receive informational presentations requested by the Committee from PG&E relating to plant safety and operations, including an update of State of the Plant including organizational changes, significant past and future plant activities, power history, significant equipment issues, Intake Cove Dredging Project, and other station activities since the DCISC's June 2024 public meeting, update on the status of NRC Performance Indicators, regulatory Issues/requests,; and PG&E's evaluations of Technical Concerns on the Seismic Safety of DCPP provided by Dr. Peter Bird in a letter to the DCISC dated May 16, 2024, and Dr. Bird's presentation to the DCISC on June 21, 2024.

2.         Afternoon Session - (10/09/2024) - 1:15 p.m.  Receive informational presentation by the Independent Peer Review Panel for Seismic Hazard Studies of DCPP on the Panel's Report on PG&E's Diablo Canyon Updated Seismic Assessment; and Committee Technical Consultants' reports on, and approval of the August 27-September 24-25, July 31, August 1, and August 21-22, 2024, fact finding visits.

            3.         Evening Session - (10/09/2024) - 5:00 p.m. Informational presentation by the Committee, report on evaluations of public input on studies by Dr. Mark T. Kirk evaluating Unit 1 reactor pressure vessel integrity, Committee consideration of the Kirk Studies and including Conclusions and Recommendations in the DCISC's 34th Annual Report.

            4.         Morning Session - (10/10/2024) - 9:00 a.m.  DCISC business session including acceptance of the Minutes of the June 20-21, 2024 public meeting, review of the Open Items List, reports by Committee Members on their activities and scheduling of future public meetings and fact-findings; and a presentation by the NRC's Senior Resident Inspector for DCPP on the NRC's Annual Assessment of DCPP's End-of Cycle Performance during Calendar Year 2023.

            5.         Afternoon Session - (10/10/2024) - 1:30 p.m.  Receive further informational presentations requested by the Committee from PG&E relating to plant safety and operations, including the Quality Verification Organization's perspective on plant performance, top issues, and recent Quality Performance Assessment Reports, update on recent campaign to move spent fuel assemblies from the Spent Fuel Pool to the Independent Spent Fuel Storage Installation; informational presentation by the Committee on the status of governmental agency interactions, responses to SB846 directives, discussion of regulatory matters including R.23-01-007 Phase 2 issues including funding for extended operations and consideration of term limits for DCISC Members, administrative matters (including ratification of Amendment No. 4 to Consulting Agreement with Dr. Mark Kirk), consideration of approval of new and revised Committee Policies, financial matters, and other Committee business; approval of the DCISC 34th Annual Report on Safety of Diablo Canyon Nuclear Power Plant Operations, July 1, 2023 - June 30, 2024; and wrap-up discussion by Committee members and confirmation of future site visits, study sessions and public meetings.

The meeting will be webcast in real time at: http://www.slo-span.org/ and through https://www.dcisc.org.
The specific meeting agenda will be available at least 72-hours before the meeting and the agenda together with the staff reports and materials regarding the above meeting agenda items will be available for public review commencing Monday, October 7, 2024, at the Special Collections and Archives Department of the Cal Poly Library in San Luis Obispo and online at at www.dcisc.org. For further information regarding the public meeting, please contact Robert Rathie, Committee Assistant Legal Counsel, SW 4th & Mission, Suite 2, P.O. Box 4253, Carmel-by-the-Sea, CA 93921-4253; telephone: 1-800-439-4688 or read the agenda on line by visiting the Committee's website at www.dcisc.org.

Dated: June 9, 2024.

DCISC Agenda for the next Public Meeting

DIABLO CANYON
INDEPENDENT SAFETY COMMITTEE ("DCISC")
(www.dcisc.org)

Committee Members:

Robert J. Budnitz Najmedin Meshkati Per F. Peterson

*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  * * * * * * * * *

Wednesday & Thursday, October 9-10, 2024
Point San Luis Conference Room
Avila Lighthouse Suites
First & San Francisco Streets, Avila Beach, California

PUBLIC MEETING AGENDA

This public meeting will be webcast in real time at:
http://www.slo-span.org/local_webcast/DCISC/stream_index.htm and through https://www.dcisc.org
This meeting is also being produced as a Zoom webinar by AGP Video Inc. and will be broadcast subsequently on San Luis Obispo local government access television, Channel 21.

Zoom Webinar Meeting ID: 820 9678 8325
Please click the link below to join the webinar
https://us02web.zoom.us/j/82096788325

Zoom Webinar Meeting Telephone Only Participation: One tap mobile: +16699006833,,82096788325# US (San  Jose), +14086380968, 82096788325# US (San Jose);     Dial(for higher quality, dial a number based on your current location):  +1 669 900 6833 US (San Jose), +1 408 638 0968 US (San Jose), +1 669 444 9171 US, +1 719 359 4580 US. +1 253 205 0468 US, +1 253 215 8782 US (Tacoma).+1 346 248 7799 US (Houston). +1 646 931 3860 US, +1 689 278 1000 US, +1 301 715 8592 US (Washington DC), +1 305 224 1968 US, +1 309 205 3325 US, +1 312 626 6799 US (Chicago),+1 360 209 5623 US, +1 386 347 5053 US, +1 507 473 4847 US, +1 564 217 2000 US, +1 646 876 9923 US (New York).

PARTICIPATION

You may participate in the DCISC's public meeting in person or in real-time by accessing the Zoom webinar meeting via the weblink and the webinar ID given above or by calling any of the phone numbers provided at the top of this agenda. Instructions on how to access, view and participate in remote meetings are also provided by visiting the DCISC's home page at https://www.dcisc.org.  Attendees can make oral comments or ask questions of the Committee Members during the webinar meeting by using the "Raise Your Hand" feature or by pressing *9 on your telephone keypad if joining by telephone only. If you are unable to participate in real-time, you may email to dcsafety@dcisc.org with the subject line "Public Comment Item#___" (insert the item number relevant to your comment) or "Public Comment - Non Agenda Item."  Comments will be reviewed and distributed before the meeting if received by Noon on Tuesday, October 8, 2024. Comments received after that will be addressed during the item and/or at the end of the meeting. All comments received will be read into and become part of the record, subject to a time limit determined by the presiding officer. Subject to the requirements to publish an agenda in advance, the Committee will have the option to modify its actions on items based on comments received.

In accordance with the Bagley-Keene Open Meeting Act (CA Govt. Code §§11120 et seq.) and the Committee's Policies, for each item on the Agenda the Committee reserves the right, at the discretion of the presiding officer, to limit the total amount of time allocated for public comment on particular issues and/or for each individual public commenter. A time limit for each public commenter will be announced during every session. For any public commenter(s) who previously requested and at the discretion of the presiding officer were granted additional time an announcement will be made at the beginning of the session. Public commenters will not be recognized more than once during public comments on matters not on the agenda or during consideration of an agenda item, but may be called upon subsequently to respond to questions from the Committee. Public commenters may not cede time to other public commenters.

Morning Session - 10/09/2024 - 9:00 A.M.

I    CALL TO ORDER - ROLL CALL

II  INTRODUCTIONS AND COMMITTEE MEMBER COMMENTS

Introduction of Committee Member Dr. Najmedin Meshkati, the appointee of the Chair of the California Energy Commission to the DCISC.

ADVISEMENT
The Committee may consider at any time requests to change the order of a listed agenda item.  Information distributed to the Committee at a public meeting becomes part of the public record of the DCISC. A copy of written material, pictures, etc. must be provided to the Committee's Legal Counsel for this purpose. Correspondence received and sent by the Committee is on file with the Office of the DCISC Legal Counsel and copies are available upon request.  Devices for attendees who may be hearing impaired are available upon request. The meeting will be webcast in real time.

III PUBLIC COMMENTS AND COMMUNICATIONS

Anyone wishing to address the Committee on matters not appearing on the Agenda may do so only at this time. (The public may comment on any matter listed on the morning's Agenda immediately following the time the matter is considered by the Committee.) There will be a time limit for each topic and/or speaker as designated by the presiding officer as announced at the beginning of this session. No action will be taken by the Committee on matters brought up under this item, but they may be referred to staff for further study, response or action.

IV  INFORMATION ITEMS BEFORE THE COMMITTEE

1. Informational Presentations Requested by the Committee of PG&E:

1. State of the Plant Update including Organizational Changes, Significant Past and Future Plant Activities, Power History, Significant Equipment Issues, Intake Cove Dredging Project, and Other Station Activities since the DCISC's June 2024 Public Meeting.
2. Update on the Status of NRC Performance Indicators, Licensee Event Reports, NRC Inspection Reports and Notices of Violation, Issues Raised by NRC Resident Inspectors, Open Compliance Issues, Status of Cross-Cutting Issues Matrix, Current and Future License Amendment Requests, and Other Significant Regulatory Issues/Requests.
3. PG&E Evaluations of Technical Concerns on the Seismic Safety of DCPP Provided by Dr. Peter Bird in His Letter to the DCISC Dated May 16, 2024, and His Presentation to the DCISC on June 21, 2024.

V    ADJOURN MORNING MEETING

Afternoon Session - 10/09/2024 - 1:10 P.M.

VI  RECONVENE FOR AFTERNOON MEETING

VII  COMMITTEE MEMBER COMMENTS

VIII PUBLIC COMMENTS AND COMMUNICATIONS

Anyone wishing to address the Committee on matters not appearing on the Agenda may do so only at this time. (The public may comment on any matter listed on the afternoon's Agenda immediately following the time the matter is considered by the Committee.) There will be a time limit for each topic and/or speaker as designated by the presiding officer as announced at the beginning of this session. No action will be taken by the Committee on matters brought up under this item, but they may be referred to staff for further study, response or action.

IX  INFORMATION ITEM PRESENTED BY THE INDEPENDENT PEER REVIEW PANEL

1. Presentation by the Independent Peer Review Panel for Seismic Hazard Studies of DCPP on the Panel's Report on PG&E's Diablo Canyon Updated Seismic Assessment.

X  TECHNICAL CONSULTANT REPORT; RECEIVE, APPROVE AND AUTHORIZE TRANSMITTAL OF FACT-FINDING REPORT TO PG&E

1. Consultant R. Ferman Wardell, PE:
   Fact-finding Topics; Report on and approval of August 27 - September 24-25, 2024, Fact Finding Report.
2. Consultant R. Ferman Wardell, PE:
   Fact-finding Topics; Report on and approval of July 31-August 1, 2024, Fact Finding Report.
3. Consultant Richard D. McWhorter Jr.:
   Fact-finding Topics; Report on and approval of August 21-22, 2024, Fact Finding Report.

XI  ADJOURN AFTERNOON MEETING

Evening Session - 10/09/2024 - 5:05 P.M.

XII    RECONVENE FOR EVENING MEETING

XIII    COMMITTEE MEMBER COMMENTS

XIV    INFORMATION ITEM PRESENTED BY THE COMMITTEE

1. Informational Presentation by the Committee:
   Report on Evaluations of Public Input on Studies by Dr. Mark T. Kirk
   Evaluating Unit 1 Reactor Pressure Vessel Integrity; Committee Consideration of the Kirk Studies and Including Conclusions and Recommendations in the DCISC's 34th Annual Report.

XV PUBLIC COMMENTS AND COMMUNICATIONS

The public may comment on the matter listed on the evening's Agenda immediately following the time the matter is considered by the Committee. Anyone wishing to address the Committee on matters not appearing on the Agenda may do so following those comments. There will be a time limit for each topic and/or speaker as designated by the presiding officer as announced after the presentation by the Committee. No action will be taken by the Committee on matters b brought up under this item, but they may be referred to staff for further study, response or action.

XVI    ADJOURN EVENING MEETING

Morning Session - 10/10/2024 - 9:00 A.M.

XVII    RECONVENE FOR MORNING MEETING

XVIII    COMMITTEE MEMBER COMMENTS

XIX    PUBLIC COMMENTS AND COMMUNICATIONS

Anyone wishing to address the Committee on matters not appearing on the Agenda may do so only at this time. (The public may comment on matters listed on the morning's Agenda immediately following the time the matter is considered by the Committee.) There will be a time limit for each topic and/or public as designated by the presiding officer as announced at the beginning of this session. No action will be taken by the Committee on matters brought up under this item, but they may be referred to staff for further study, response or action.

XX   ACCEPTANCE OF MINUTES

Minutes of June 20-21, 2024, Public Meeting.

Review/Accept

XXI   ACTION ITEMS

Review of Open Items List.

Discussion/Action

XXII   DISCUSSION, DIRECTION AND ACTION, AS APPROPRIATE, BY THE COMMITTEE, CONSULTANTS & COUNSELPublic Outreach, Site Visits and Other Committee Activities; Scheduling and Confirmation of Future Fact-Finding Visits and Public Meetings.

1. Public Outreach, Site Visits and Other Committee Activities; Scheduling and Confirmation of Future Fact-Finding Visits and Public Meetings.
2. Documents Provided to the Committee

XXIII   INFORMATION ITEM PRESENTED BY THE NUCLEAR REGULATORY COMMISSION SENIOR RESIDENT INSPECTOR FOR DCPP

1. Presentation by the NRC's Senior Resident Inspector for DCPP Mr. Mahdi Hayes on the NRC's Annual Assessment of DCPP's End-of Cycle Performance during Calendar Year 2023.

XXIV  ADJOURN MORNING MEETING

Afternoon Session - 10/10/2024 - 1:30 P.M.

XXV  RECONVENE FOR AFTERNOON MEETING

XXVI  COMMITTEE MEMBER COMMENTS

XXVII  PUBLIC COMMENTS AND COMMUNICATIONS

Anyone wishing to address the Committee on matters not appearing on the Agenda may do so only at this time. (The public may comment on any matter listed on the afternoon's Agenda immediately following the time the matter is considered by the Committee.) There may be a time limit for each topic and/or speaker as designated by the presiding officer. No action will be taken by the Committee on matters brought up under this item, but they may be referred to staff for further study, response or action.

XXVIII   INFORMATION ITEMS BEFORE THE COMMITTEE (Cont'd.)

2. Informational Presentations Requested by the Committee of PG&E (Cont'd.):

4. Quality Verification Organization's Perspective on Plant Performance, Top Issues, and Recent Quality Performance Assessment Reports.
5. Update on Recent Campaign to Move Spent Fuel Assemblies from the Spent Fuel Pool to the Independent Spent Fuel Storage Installation.

XXIX   DISCUSSION, DIRECTION AND ACTION, AS APPROPRIATE, BY THE COMMITTEE, CONSULTANTS & COUNSEL

1. Status of Governmental Agency Interactions, Responses to SB846 Directives, Discussion of Regulatory Matters including R.23-01-007 Phase 2 Issues Including Funding for Extended Operations and Consideration of having Term Limits for DCISC Members, Administrative Matters (including ratification of Amendment No. 4 to Consulting Agreement with Dr. Mark Kirk), Consideration of Approval of New and Revised Committee Policies, Financial Matters, and Other Committee Business.
2. Approval of the DCISC 34th Annual Report on Safety of Diablo Canyon Nuclear Power Plant Operations, July 1, 2023 - June 30, 2024.

XXX    CONCLUDING REMARKS & DISCUSSION BY COMMITTEE MEMBERS OF FUTURE DCISC ACTIVITIES

1. Future Actions by the Committee.
2. Further Information to Obtain/Review.
3. Confirmation of Future Site Visits, and Public Meetings.

XXXI  ADJOURNMENT OF THE ONE HUNDRED AND NINTH PUBLIC MEETING

The DCISC's policy is to schedule its public meetings in locations that are accessible to people with disabilities and to remain in compliance with state guidelines on communicable disease prevention. Hand sanitizers and face coverings are available in the meeting room. The Avila Lighthouse Suites Point San Luis Conference Room is a wheelchair accessible facility. A person who needs a disability-related accommodation or modification in order to participate in the meeting may make a request by contacting the DCISC office (in CA 800-439-4688 or (831) 647-1044) or by sending a written request to the DCISC office at P.O. Box 4523, Carmel-by-the-Sea, CA 93921-4523. Providing your request at least five business days before the meeting will help ensure availability of the requested.

M I N U T E S
of the
DIABLO CANYON INDEPENDENT SAFETY COMMITTEE'S
OCTOBER 9-10, 2024, PUBLIC MEETING
[As  approved at the February 19-20, 2025, Public Meeting.]

Wednesday & Thursday
October 9-10, 2024
Avila Beach, California
Also conducted as a Zoom Webinar

Notice of Meeting.

            A legal notice of the public meeting was published in the San Luis Obispo Tribune and a display advertisement was published in the New Times, both local newspapers of general circulation, and mailed and emailed to the media and those persons on the Committee's mailing list. The meeting agenda and the complete agenda packet for the meeting and the informational presentations made during the meeting together with the fact finding reports to be considered for approval were posted on the Committee's website at prior to the meeting. The meeting agenda contained information on how to access the webinar using a computer, cellphone or a telephone. This in-person meeting was also produced as a Zoom webinar by AGP Video, Inc. and was webcast live on SLO-SPAN at http://www.slo-span.org and through https://www.dcisc.org and was subsequently broadcast on San Luis Obispo, California, local government access television Channel 21.

            CALL TO ORDER - ROLL CALL

            The October 9, 2024, public meeting of the Diablo Canyon Independent Safety Committee (DCISC), the one hundred and ninth public meeting of the Committee, was called to order by Committee Chair Dr. Per F. Peterson at 9:00 a.m. Dr. Peterson welcomed those present and he then introduced a new member of the Committee, Dr. Najmedin Meshkati, a Professor from the University of Southern California. Dr. Peterson requested Dr. Meshkati to say a few words concerning his background.

            Dr. Meshkati stated he is a Professor of Civil/Environmental Engineering, Industrial Systems Engineering and International Relations and he has been at the University of Southern California for almost 39 years as a professor. He commented his research concerns safety culture, human systems, intervention and human factors of complex safety critical systems. He remarked he has worked in the field of nuclear safety for many years and in that work he visited the Three Mile Island Nuclear Generating Station in Pennsylvania, the Chernobyl Nuclear Power Plant in the Ukraine, and the Fukushima Daiichi Nuclear Power Plant in Japan. Dr, Meshkati reported he has also worked in the field of aviation safety and recently served on a Federal Aviation Administration panel investigating the Boeing Company and worked with the Deepwater Horizon accident investigation and Fukushima Daiichi lessons learned panels, as well as in the healthcare patient safety industry. Dr. Meshkati stated he has received and read a number of comments from members of the public and he expressed his thanks to California Energy Commission Chair Mr. David Hochschild for his appointment and stated that he looks forward to learning from his colleagues on the Committee and from those at Diablo Canyon Power Plant (DCPP or the plant) and at the Pacific Gas & Electric Company (PG&E).

            Dr. Peterson then introduced and briefly reviewed the professional background and appointment to the DCISC for his fellow Member, Dr. Robert J. Budnitz, the appointee of the Attorney General of California. Dr. Budnitz then briefly reviewed Dr. Peterson's professional background and reported Dr. Peterson serves on the DCISC as the appointee of the Governor.

Present:	Committee Member Robert J. Budnitz Committee Member Najmedin Meshkati Committee Member Per F. Peterson
Absent:	None

II         INTRODUCTIONS

            Dr. Peterson introduced and briefly reviewed the professional backgrounds of the Committee's Technical Consultants and Assistant Legal Counsel: Technical Consultants Mr. Richard D. McWhorter Jr., Mr. R. Ferman Wardell, P.E., and Dr. Andrew C. Kadak, and DCISC Assistant Legal Counsel Mr. Robert W. Rathie.

III        PUBLIC COMMENTS AND COMMUNICATIONS

            The Chair invited any members of the public who wished to address remarks to the Committee on items not appearing on the agenda for the public meeting to do so at this time. Mr. Rathie reported this meeting is being livestreamed and broadcast on the internet and he welcomed and introduced the technicians from AGP Video who provide this aspect of the Committee's public meetings. He then reviewed the rules adopted to entertain public comment on an equitable basis for all as follows:

→        Speakers should come to the podium and identify themselves;

→        Speakers will be recognized by the Chair in order, first from among those present in the room and then among those attending virtually;

→        Remarks will be limited to four minutes, but this may be varied for each session;

→        Comments from public officials may be taken before those of members of the general public;

→        Speakers may not cede their time to other speakers;

→        Groups may be asked to appoint a spokesperson;

→        Each speaker may only address the Committee once under either the time for items not on the agenda, but within the Committee's subject matter jurisdiction (i.e., the operational safety of DCPP) or when a matter listed on the agenda is heard;

→        The DCISC Chair reserves the right to stop any speaker if he or she believes the speaker   is out of order;

→        The Committee reserved the right to modify the rules in the interest of conducting an effective meeting including granting extra time to certain speakers upon request;

→        Writings used in conjunction with remarks should be provided to the Committee's Legal Counsel; and

→        Email comments received will be read into the record subject to the time limit.

Mr. Rathie reported the Committee's public meeting agendas provide for comments on matters not on the agenda and within the Committee's subject matter jurisdiction at each session and for public comments on matters listed on the agenda to be heard at the time the matter is considered by the Committee. Mr. Rathie stated that when all the members of the Committee are present in the meeting room the hybrid component, which is the ability to participate via Zoom, is provided as a convenience and should the connection be lost the Committee will continue conducting business without the Zoom component. Finally, he remarked the Committee recognizes the technical nature of the matters under its consideration and he stated and the Chair confirmed the Committee welcomes and seeks to be as forthcoming as possible concerning public comment. Dr. Peterson observed the Committee records public comment in the meeting Minutes and in its Open Items List.

            There were no comments from the public at this time.

            Dr. Peterson then introduced Ms. Brandy Lopez, DCPP Strategic Initiatives Licensing Principal. Ms. Lopez plays key roles on behalf of PG&E and DCPP as the principal liaison with the DCISC in coordinating the Committee's activities, providing information, and facilitating the Committee's public meetings and the frequent fact-finding visits conducted by a single member and one of the technical consultants. Dr. Peterson also introduced Mr. Tom Jones, DCPP Senior Director for Regulatory, Environmental and Repurposing, and asked him to introduce the first of the informational presentations requested by the Committee for this meeting.

IV        INFORMATIONAL ITEMS BEFORE THE COMMITTEE

            Mr. Jones introduced DCPP Station Director Mr. Justin Rogers to make the first presentation and reported Mr. Rogers leads a team of more than 500 nuclear professionals in the Operations, Maintenance, Chemistry Radiation Protection organizations and in other safety organizations. Mr. Rogers began his career at DCPP in 2013, received a Senior Reactor Operator License in 2016 and worked in increasing positions of responsibility in the Training and Outage Management organizations. Mr. Rogers is a veteran of the U.S. Navy and holds a Bachelor of Science Degree in Nuclear Energy Engineering Technology from Thomas Edison State University.

State of the Plant Update Including Organizational Changes, Significant Past and Future Plant Activities, Power History, Significant Equipment Issues, Intake Cove Dredging Project, and Other Station Activities since the DCISC's June 2024 Public Meeting.

            Mr. Rogers remarked this was his second time presenting to the Committee and he thanked Dr. Meshkati for joining the Committee. He stated he was honored to be representing PG&E and the DCPP team.

            Mr. Rogers reported Unit 1 and Unit 2 are presently safely and reliably operating at 100% power with no challenges to safety or generation and all NRC Performance Indicators are Green. He reviewed the power history for both units and reported a refueling outage for Unit 2 was conducted in April and May 2024 and Unit 2 has been at 100% power since. Unit 1 has been at 100% power in 2024 except for a period in August and September when bio-fouling cleaning (also known as a "pick and dredge") was performed in the tunnels to remove items off the condenser tube sheets and to dredge to remove material in the circulating water tunnels and accordingly power was reduced to 50%. Mr. Rogers remarked that DCPP has seen an increase in biofouling in 2024 and recently the units were curtailed to perform another pick and dredge. Mr. Rogers reported in timing the pick and dredge operations DCPP consults with the California Independent System Operator (CAL ISO) which manages the flow of electricity across high voltage, long-distance power lines, operates a competitive wholesale energy market, and oversees transmission planning. In response to Consultant McWhorter's inquiry Mr. Rogers stated that typically a pick and dredge is required eight to twelve months after a refueling outage. In response to Consultant Kadak's query Mr. Jones stated the sludge buildup is normal and is not a sedimentary product of the Intake Cove dredging project, but rather consists of shell products from mollusks. He remarked that the Intake Cove dredging project employed turbidity controls.

            In response to Consultant Wardell's inquiry Mr. Rogers stated capacity factor is calculated in different variations, but he confirmed Dr. Budnitz' observation that 100% power is predicated on a particular temperature in the ultimate heat sink (the Pacific Ocean) and colder ocean water produces better thermodynamic efficiencies which can result in the plant exceeding what would otherwise be the capacity factor.

            In response to Consultant McWhorter's request, Mr. Rogers reported that following Unit 2's recent refueling outage the unit experienced a steam leak from a valve on the secondary system[1] and power was stabilized, with the turbine off line, but with the reactor on line, to investigate the leak which required a power reduction to repair. A cause evaluation is being performed which will include review of the extent of condition to assess if broader corrective actions are necessary. Dr. Budnitz and Mr. McWhorter stated the DCISC would take an action to review the cause evaluation report when it is complete. In response to Dr. Meshkati's question Mr. Rogers reported the leak was detected during rounds made in the Turbine Building by the non-licensed operators.

            Mr. Rogers reported the Quality Verification Director is taking a leave of absence and Mr. Chris Newport will be filling that role. He then provided and discussed an update on station activities as follows:

→        June-July 2024: Intake Dredging Project

→        July-Oct. 2024: Used Fuel Outage Campaign (on track to complete)

→        June 10-13, 2024: NRC Age-Related Degradation Inspection

→        July-August 2024: Multiple License Renewal Inspections

→        June 24-27, 2024: Nuclear Safety Oversight Committee (NSOC) On-site Observations

→        July 15, 2024: NRC Operating Exam

→        July 29-Aug 2, 2024: NRC Emergency Preparedness Exercise

→        August 5-19, 2024: World Association of Nuclear Operators (WANO) Peer Review

→        August 12-25, 2024: NRC Radiation Protection Inspection

→        August 24, 2024: Annual Siren Test

→        September 9-13, 2024: NRC Problem Identification & Resolution Inspection

            Mr. Rogers reported the NRC inspections for license extension are primarily related to age-related degradation and no items of significance have been identified. He reported six reactor operators were licensed from the July 15, 2024 examinations and ten senior reactor operators were licensed. There were no failures as a result of the July 2024 examinations. In response to Dr. Meshkati's query Mr. Rogers reported the World Association of Nuclear Operations (WANO) peer review found no significant issues from its review of the Operations, Training, Maintenance, Engineering organizations, configuration control and management, emergency preparedness, fire protection and performance by supervisors and leadership. In response to Consultant Kadak's query Mr. Rogers reported the DCPP Nuclear Safety Oversight Committee (NSOC) found the plant has a strong nuclear safety culture. He reported the NSOC visits the site three times each year. Mr. Rogers remarked the NSOC and the DCISC both provide quality reviews with similarities, but the NSOC is focused on ensuring nuclear safety is maintained from the NRC standpoint. He confirmed the NSOC reviews the reports by the DCISC. Dr. Budnitz observed the DCISC representatives attend the NSOC exit meetings with plant management and review on a confidential basis NSOC's reports and this represents, together with the similar review of the reports of the Institute of Nuclear Power Operations (INPO) and WANO, a valuable opportunity for the DCISC. Dr. Peterson remarked as the DCISC identifies new issues from its review of NSOC, INPO and WANO reports the DCISC follows up on those issues independently. Dr. Budnitz observed the NSOC and INPO reviewers consist of leading nuclear engineering and safety experts.

            Mr. Rogers reviewed upcoming activities as follows:

→        Nuclear Safety Oversight Committee (NSOC) - October 21-24, 2024

→        Diesel Generator 1-3 Maintenance Outage Window (MOW) - October 13-21, 2024

            Mr. Jones then introduced the DCPP Director of Risk and Compliance Mr. Jordan Tyman to make the second presentation on the NRC's assessment of plant performance. Mr. Jones reported Mr. Tyman is responsible for governance and oversight of the Risk Management Program for PG&E's power generation facilities as well as for Regulatory Services, Nuclear Cyber Security and Emergency Planning at DCPP. Mr. Jones reported Mr. Tyman has been employed by PG&E for more than eight years and spent ten years prior to coming to PG&E at Westinghouse Electric Corporation, in support of the development of Westinghouse's AP1000 pressurized water reactor and a number of Westinghouse's subsidiaries. Mr. Jones reported Mr. Tyman is a member of the California Polytechnic University at San Luis Obispo (Cal Poly) Cyber Security Program Advisory Board and holds a Degree in Mechanical Engineering from the University of Massachusetts.

A.        Update on the Status of NRC Performance Indicators, Licensee Event Reports, NRC Inspection Reports and Notices of Violation, Issues Raised by NRC Resident Inspectors, Open Compliance Issues, Status of Cross-Cutting Issues Matrix, Current and Future License Amendment Requests, and Other Significant Regulatory Issues/Request.

            Mr. Tyman reported in his presentation he would cover the period in 2024 from July to September during which DCPP continued to perform at the top of the industry from a regulatory perspective and in which the NRC performed 1,500 hours of inspection activity. This inspection activity included inspections by the two NRC resident inspectors as well as seven routine programmatic evaluation inspections. In response to Consultant McWhorter's question Mr. Tyman reported the routine inspection cycle activity for DCPP was consistent with industry norms with some inspections such as for Problem Identification and Resolution having larger inspection teams. Mr. Tyman and Mr. Jones stated they did not know the number of inspection hours expended by inspection teams in furtherance of license renewal but Mr. Tyman remarked this was consistent with industry norms for license renewal and he offered to subsequently provide that information to the Committee.

            Mr. Tyman reported all violations received during the period of his report were of very low safety significance and DCPP continues to be in the highest performance category as assessed by the NRC Reactor Oversight Process (ROP) which uses 16 separate indicators to evaluate performance. He stated all indicators meet expected performance levels and are in Green[2] status. Mr. Tyman reported the violations received fell within two themes, one of which was the effective use of some procedures and the other the opportunity to improve configuration control.

            In response to Dr. Peterson's request Mr. Tyman stated a fan which tripped off but was not declared to be inoperable immediately was an example of lack of configuration control. Dr Budnitz observed that for the period the fan was inoperable the plant was in an off-normal configuration, a configuration which was not known to all plant personnel. To which Mr. Tyman replied this had extremely low safety significance from a probabilistic risk assessment (PRA) perspective and the Operations Department and the Control Room personnel were aware of and understood the condition. Consultant McWhorter observed this represents more than a procedural issue, as it involves an untimely recognition of entry into Technical Specification[3] (TS) 303 as equipment configuration on opposite trains[4] were in different situations not covered by Technical Specification which adds specific timing requirements for dealing with the situation in shut down. Mr. Tyman reported the other fan was in service, but as the emergency diesel generator (EDG) was out of service for a planned maintenance window there was no backup power for the other fan and the Technical Specification cited by Mr. McWhorter was entered and the delay in recognizing this was part of the NRC's concern. Dr. Budnitz remarked this off-normal configuration represents a safety compromise in the sense that there are some accident sequences that might arise where having the extra equipment would be important and it is necessary to work out the probability of such sequences and their importance and he observed Mr. Tyman reported that probability was calculated and found to be very small. Mr. Tyman, in response to Dr. Peterson's query reported plant personnel identified and self-reported the problem and Dr. Peterson observed it is important that low level problems continue to get reported and this willingness to report problems is a sign of a healthy nuclear safety culture. Dr. Budnitz reported qualitative judgments as to safety significance are something that each person makes each day and in certain industries, including nuclear, there are quantitative methods for quantifying many of these decisions as to their safety significance and for a plant such as DCPP this process requires use of those quantitative analytic methods and judgment based on experience.

            Mr. Tyman reported during this report period there were no Licensee Event Reports (LERs) issued by DCPP and there are two NRC inspections coming in the next reporting period for the Independent Spent Fuel Storage Installation (ISFSI) security and for Security organization access control, both scheduled for October 2024. In concluding his presentation Mr. Tyman reported License Amendment Requests (LARs) have been submitted for NRC review including for 10 CFR[5] 50.59 classification of structures, systems and components and for industry improvements to the Technical Specifications using industry standard submittals.

            In response to Consultant McWhorter's inquiry Mr. Tyman reported all items on the Cross Cutting Matrix[6] for DCPP are within NRC reporting thresholds and each has considerable margin.

            Following Mr. Tyman's presentation, Ms. Linda Parks, a local resident, was recognized and in response to her request for other examples of issues with configuration control Dr. Budnitz referred Ms. Parks to the Committee's fact finding reports where examples are often documented.

            A short break followed.

PG&E Evaluation of Technical Concerns on Seismic Safety of DCPP Provided by Dr. Peter Bird in His Letter to DCISC Dated May 16, 2024, and His Presentation to the DCISC on June 21, 2024.

            Dr. Peterson asked PG&E Senior Director, Regulatory, Environmental and Repurposing, Mr. Tom Jones to introduce the next speaker.

            Mr. Jones introduced Mr. Jeff Bachhuber, Director of the PG&E Geosciences Department, and reported that Mr. Bachhuber and his team have responsibility for seismic safety across the 48 counties in California in which PG&E has assets including buildings, dams, and the nuclear facility. Mr. Bachhuber has 38 years of experience in nuclear and critical facility geohazard and seismic evaluations and joined PG&E in 2016. Mr. Bachhuber is a California professional geologist and certified engineering geologist. He's a member of the National Institute of Building Sciences Lifelines Panel, and an advisor to the National Science Foundation on the geotechnical extreme event team, and he is also a geohazard lead for the American Society of Civil Engineers.

            Mr. Bachhuber stated this presentation was developed at the request of DCISC to walk through the PG&E's review and response to contentions filed by the local group San Luis Obispo Mothers for Peace (Mothers for Peace) and Mothers for Peace consultant Dr. Peter Bird regarding the PG&E 2024 Updated Seismic Assessment developed in response to the mandate of California Senate Bill 846[7] (SB 846). He reported to date his team has received and reviewed the various contentions and declarations and also attended some of the presentations that Dr. Bird has delivered. Mr. Bachhuber noted that the information PG&E has received has been a series of declarations of proponent views and postulations. PG&E has yet to receive a detailed report backed by data that has been peer reviewed and this has impacted the level of detail in PG&E's response. But he stated PG&E has seriously considered all the contentions and comments received. He reported he would be joined in the presentation by Dr. Albert Kottke and Dr. Chris Madugo.

            Mr. Bachhuber reported the 2024 Updated Seismic Assessment was completed and submitted in February 2024 and followed the NRC's Senior Seismic Hazard Analysis Committee (SSHAC) process including developing the center, body and range of technically defensible interpretations for the datasets reviewed. The Technical Integration Team and Participatory Peer Review Team were comprised of known experts in the area of nuclear project seismic studies, seismic research, and also the Central California coast geology of seismic sources. Mr. Bachhuber stated the 2024 Updated Seismic Assessment went beyond the SSHAC process in that an additional third party review by members of the B. John Garrick Institute for the Risk Sciences at the University of California at Los Angeles was conducted. He reported key findings of the 2024 Updated Seismic Assessment were that in reviewing the information and work from the 2015 comprehensive SSHAC Level Three seismic update only one minor change was identified, that being in the source characterization of seismic hazard-significant sources with no resulting significant increase in seismic risk to the plant. The 2024 Updated Seismic Assessment found no new information that would significantly change the 2015 Seismic Source Characterization study's conclusions and the 2024 Updated Seismic Assessment confirms the seismic safety of DCPP.

            Mr. Bachhuber reported PG&E's team remained available to the DCISC consistently through the review process to clarify and respond to questions including concerning the scope of the 2024 Updated Seismic Assessment. The DCISC and representatives from the State of California Department of Water Resources (DWR) participated as observers during the working meetings in the summer and fall of 2023. He reported the DCISC and DWR received the final report inn February of this year, and during the review PG&E has interfaced with and addressed questions including those from San Luis Obispo Mothers for Peace and also reviewed comments from the CPUC Independent Peer Review Panel. Consultant McWhorter observed and Mr. Bachhuber agreed the DCISC representatives very intentionally participated in the process only as observers and waited until the 2024 Updated Seismic Assessment was complete before commenting on the process or the adequacy of the results.

            Mr. Bachhuber introduced Dr. Chris Madugo and stated Dr. Madugo has been a principal seismic geologist in the PG&E Geosciences Department since 2014 and he has over twenty years' experience on fault studies and seismic source characterization. Dr. Madugo holds Masters and Doctorate Degrees in Geology from Central Washington University and Oregon State University respectively. He has performed numerous global earthquake recognizance missions and is well known in the research community because of his extensive collaboration in support of research. Dr. Madugo manages the PG&E U.S. Geological Survey Cooperative Research Agreement which is focused on seismic sources. In the SB846 program Dr. Madugo served as co-sponsor addressing seismic source characterization issues.

            Mr. Bachhuber then introduced Dr. Albert Kottke to continue the presentation and stated Dr. Kottke has been a principal geotechnical engineer in the PG&E Geosciences Department since 2017 and has worked in nuclear site specific ground motions and seismic hazards since 2012, and holds a Doctorate Degree in Civil Engineering from University at Texas, Austin Texas. Dr. Kottke is a licensed professional engineer in California and worked as a post-doctoral researcher at the Pacific Earthquake Engineering Research Institute and as a peer for development of components of the NGA (Next Generation Attenuation) West Two and NGA East projects[8]. He also participated in seismic hazard studies as a SSHAC technical integration team member for the Idaho National Laboratory and is a resource expert for the Natrium Project in Los Alamos National Lab. For the SB 846 project Mr. Bachhuber reported Dr. Kottke was a co-sponsor addressing ground motion issues.

            Dr. Madugo stated his part of the presentation will focus on primary source characterization, characterization of faults, where they are, how fast they are moving, the rate of earthquakes, the size of earthquakes and then Dr. Kottke will discuss ground motions and the seismic hazards process.

            Dr. Madugo observed regarding the contentions raised by Dr. Bird in his May 16, 2024, letter to the DCISC that these may be understood as: (1) is there evidence for a previously uncharacterized thrust fault beneath Diablo Canyon, one that has not been identified before? (2) Is there evidence that model slip rates for faults bounding the Irish Hills located behind Diablo Canyon are higher than have been presented in models? And (3) does the Noto earthquake that happened on January 1, 2024, in Japan indicate that there's an increased seismic hazard and risk for Diablo Canyon?

            Dr. Madugo provided a preview of the findings, based on the technical issues raised by Professor Bird, which include the conclusion that there's no evidence that's been provided to support the existence of an inferred new fault offshore of Diablo Canyon. He stated that the novel slip rate approaches proposed by Dr. Bird are not validated and have poorly characterized uncertainties and are not yet accepted by the seismic hazard community compared to the methods that PG&E has used in its seismic report. He reported the slip rates modeled by PG&E for reverse faults are consistent with rates modeled using geodetic method including those by Dr. Bird. With respect to the Noto earthquake in Japan Dr. Madugo stated PG&E evaluated this earthquake and provided an internal report [by Lettis Consultants International] which was provided to DCISC and Dr. Madugo stated PG&E does not feel that there is a direct analog for seismic hazard assessment at Diablo Canyon, based on differences in geology, seismicity/activity rates, and the scale of the two regions and it is not applicable to estimate core damage. He reported the PG&E hazard model captures the center, body and range of technically defensible interpretations and it has been reviewed at multiple levels, including acceptance by the NRC.

            Dr. Madugo stated with respect to the tectonic environment along Central California coast the contentions focus on convergence or contraction across the Irish Hills at Diablo Canyon, but the region is characterized by both strike slip lateral motion where the earth isn't going up, similar to the San Andreas Fault which he described as the primary mode of deformation in California. He reported on the California Central Coast there are localized areas where you also have compression or contraction and the ground is going up. He stated in the Diablo Canyon region both styles of deformation exist and this is informed by observing faulting from decades of studies, stress inversion, and from data from the San Simeon earthquake in 2003 which he stated had both types of deformation involved in the primary shock and in the aftershocks.

            Dr. Madugo stated concerning the model elements the first part of a source characterization is to identify the faults around the site and he displayed a map of faults around DCPP for which most have been mapped in detail based on multiple different methods, subsurface investigations, and surface mapping. Sensitivity studies show that the faults that are most important to seismic hazard at the plant include the Hosgri, Los Osos, the San Luis Bay, and Shoreline Faults which were labeled on the map. He pointed out the overlay lines representing the source characterization which are used to model the size of earthquakes and also the distance from the plant which he described as an important metric. Dr. Madugo explained seismic faults aren't just lines on the surface, they are planes and the planes are directly correlated to the magnitude of earthquakes. The faults extend into the ground, and they can have earthquakes in areas down to about twelve kilometers depth. He commented there is some uncertainty in how these faults project down into the subsurface and in the 2015 and 2024 models three different geometry models on how the faults project into the earth were used.

            Dr. Madugo described and indicated on a map the first model as the outward vergent model. He stated if one were to look into the earth's surface under the Irish Hills the profile would show the projections of the fault into the subsurface to the base of the seismogenic zone, the base of the zone where earthquakes occur. He reported with this model the San Luis Bay fault on the southwest and the Los Osos fault on the northeast work together to uplift the Irish Hills, together with a bit of lateral movement, together with additional lateral movement on the vertical Hosgri and the Shoreline Faults. Dr. Madugo stated the geometry of these faults are consistent with multiple datasets, geomorphology, surface characteristics of the earth, geophysics, seismicity, stress and analog models. By analog models he stated he means other places in the world where similar geology and tectonics occur, and where this kind of geometry exists. He reported one model that was an anchor for these three geometry models was the San Simeon earthquake in 2003 with a magnitude of 6.6, and a 30 kilometer long rupture in the subsurface. Below are the different geometries that were observed through profiling across that rupture which showed two faults with geometries very similar to what was seen in San Simeon. He observed there are multiple lines of evidence that show what the dip or the angle that the faults go into the subsurface from the San Simeon earthquake and there is a focal mechanism data first movement of the rupture that showed a dip of 46°. Moment tensor showed dips of 32°, 50° and 58° and then detailed seismic modeling of aftershocks going along these fault surfaces showed dips of 60° and changing to 35°, then all the way up to 90°. Dr. Madugo stated he highlighted this data as that in one of Dr. Bird's contentions it was claimed that dips in the range of 50° or greater were impossible in the area of DCPP due to the type of bedrock and Dr. Bird says dips up in the 70° to 80° degree range were ridiculous and Dr. Madugo stated PG&E based its model on observed dips in the same tectonic environment.

            Dr. Madugo remarked that because PG&E was trying to capture the center, body and range, alternative models that explore uncertainty in the different dips were studied. They describe what he termed the southwest vergent model for which the San Luis Bay fault is the main driver, and the Irish Hills are uplifting primarily on that San Luis Bay fault, and the Los Osos fault in the northeast is a secondary structure. He contrasted this with the northeast vergent model which has the Los Osos fault driving the uplift of the Irish Hills and the San Luis Bay fault as a secondary structure. In response to Consultant Kadak's question Dr. Madugo replied all three models are weighted as part of a logic tree.

            Dr. Madugo reported that in terms of how fast the faults are moving vertically on either side of the Irish Hills there is good datum which consists of marine terraces. These terraces were carved during periods of sea level change during high sea levels, and they ring the Irish Hills. There is a suite of coastal marine terraces which wrap around the "nose" of the Irish Hills, and there are other terraces on the other side, on the northeast side of the Irish Hills. He described a map showing the elevations and where those terraces are crossed by the San Luis Bay fault. He stated that as one continues to the northwest and around the nose of the Irish Hills, the elevations within the uncertainty generally stay the same as there are no other faults cutting those terraces. He reported those profiled faults are turned into uplift rates and used to estimate slip rates for the San Luis Bay and Los Osos Faults. He reported for this kind of data, the terraces are 125,000 years old or younger and for low slip rate faults, he remarked these are considered the gold standard. He remarked concerning [uplift] measurements on both sides of the fault and really good age dates [for the terraces]

            Dr. Madugo observed once one understands where the faults are and their geometries and their rates, then you need to consider what kind of earthquakes can occur on those faults, which he stated is structurally related to the length and the width of the area of the fault that is rupturing. He displayed a map showing the surface extent of the fault and the fault's extending to depth, and he observed that is the part of the fault that would rupture during an earthquake. As part of the development of the model one finds all the different earthquakes that could occur on a fault. For the San Luis Bay Fault, Dr. Madugo stated one could have magnitude sixes, or if linked to other faults all the way up to magnitude eight seismic events and the slip rate allocated to different ruptures which is termed "topologies." For different geometry models Dr. Madugo stated many different variations of the different types of earthquakes that can occur have been proposed. He remarked this is important because it is directly related to the Noto Earthquake. He reported one can see ruptures of the San Luis Bay Fault, ruptures of connected faults to the southeast, connections to the Hosgri Fault, the Shoreline Fault, so many different rupture scenarios and Dr. Madugo stated the reason that this is considered in the model is that there isn't a long enough seismic record to see which ones are the dominant ruptures that occur. These are all the possible ruptures that could happen and data showing what happened in the past need to be considered relative to what will happen in the future.

            In response to Consultant Kadak's query Dr. Madugo stated the scenarios he described were all weighted and considered in the model and if one were to choose one scenario that would be a deterministic scenario based hazard assessment, but the process he described was probabilistic, which is logic tree based and considers all the different scenarios.

            Dr. Madugo observed if one looks at the data he presented there are two earthquakes, magnitudes, 6.2 and 6.4, related to the two different lengths between the node he indicated on a map he displayed and he remarked the map identifies larger scenarios with a magnitude 7 for what is termed a characteristic earthquake of magnitude 7.4 for what the study would term the maximum earthquake for this series of faults interconnecting together. He stated there are other scenarios where the faults could link up with the Hosgri fault, which is offshore and goes all the way up to the Oregon border, for which the study indicates could produce earthquakes greater than magnitude 8 but these have a very low probability of occurring. Dr. Kottke stepped in and explained these events are assessed on the maximum magnitude and for these scenarios maximum magnitude is defined in PG&E's distribution. Dr. Kottke stated PG&E knows the slip rate from its fault study, and so can use that to develop a magnitude frequency distribution of the variation from small magnitude to large magnitude event, which varies for the characteristic event for that fault. In reply to Dr. Kadak's question Dr. Kottke confirmed the slip rate defines how much moment has accumulated with time because moment is related to how much slip is occurring, or building up, which is a constant. The question is how that slip is then turned into various earthquake sizes and probabilities of occurrence and the different alternatives represent the terms of what the largest magnitude event could be to consume that slip and the probability of occurrence. He stated this information is contained in the 2015 Seismic Source Characterization, a SSHAC Level Three study, and in the 2024 Updated Seismic Assessment.

            Dr. Madugo observed he had described different potential options for earthquakes and what is termed characteristic earthquakes for the Diablo Canyon area. He remarked for the Noto earthquake the contentions based on Dr. Bird's work state that there's one earthquake that is magnitude 7.5 is the best single choice that's occurred in another part of the world, and that is the earthquake that is appropriate to use for DCPP. He remarked the scale of the two sites is different and the faults that are closest to DCPP are very likely going to generate in the magnitude 6 range. He acknowledged the events can get up to 7 magnitude but there is no basis for saying that a magnitude 7.5 earthquake. He reported the scenarios can get up to a magnitude 7.4 for the maximum possible earthquake but there is no basis for a claim that a magnitude 7 earthquake is the characteristic, the typical, large earthquake that happens offshore at the plant and that is what his review of the model shows, that is, if one doesn't have information for the earthquakes that have happened in your area, one cannot say what that characteristic earthquake will be and this is true even for Japan where they have a lot more earthquakes. For the Noto event he stated there is a range of magnitude 6 to 7, and if one were to do a seismic hazard model for a nuclear plant in the vicinity of the Noto Peninsula one would need to consider the range of possible earthquakes and not just assume that magnitude 7 represents the characteristic large earthquake.

            Dr. Madugo reported that in addition to mapping and characterizing the fault PG&E also has a background seismicity model. This model accounts for seismicity on faults that either have not been identified as they are beneath the ground's surface and don't have a surface expression, or they are faults that we've identified and found to have a very, very low rate such that they are not suitable to be put in a source model as an independent source. These could potentially have smaller earthquakes. This seismicity model was done through a local area source zone around the plant, and he displayed a map. Dr. Madugo stated these are all inferred faults and they have varying dips and angles beneath the ground surface. Many of them go beneath the plant. Again, he stated, through the logic tree the range of geometry in dips is considered and this accounts for seismicity on faults that PG&E does not know about or which have not been characterized very well.

            Dr. Madugo stated he wanted to highlight that everything that he mentioned in the background information he provided was based on reports dating back to the 1980s including the Long Term Seismic Program in 1988 and 1990, and included the 2011 Shoreline Fault Report and the AB 1632 Report. Work was done in support of each of these reports on mapping, geophysics, bathymetry and each was a long multi-year project with experts and were peer reviewed and followed the process he outlined for the Committee, that is, mapping the faults at the surface, estimating the projections of the fault at depth based on analog models or data, developing different rupture scenarios and slip rates, and then going on to assess hazard and risk. These data reports and the seismic hazard reports have multiple levels of review and acceptance by the NRC, the Independent Peer Review Panel (IPRP), the Diablo Canyon Independent Safety Committee, and the State Department of Water Resources. He reiterated Mr. Bachhuber's observation that contentions are usually from one person, one expert, without a full technical report to support them. They have no review, no regulatory review as of this point and this is a contrast that should be considered.

            In response to Consultant Kadak's query concerning the IPRP's research Dr. Madugo replied their research was with respect to the geometry of the fault beneath the Irish Hills and the IPRP has explored the weighting of the scenarios and the confidence level attributed to them and believes that there are new methods that could contribute to this potential research to better constrain the models. He remarked PG&E has had discussions with the IPRP. He stated that in terms of the broader question of why after all the work that's been done we do not have a better constraint on some of these geometries the answer is the work is really difficult and what the IPRP is arguing is that PG&E could do more work to further reduce those uncertainties including in terms of the geometries for the models and in terms of assessments of how those geometries impact the hazard at the plant. Dr. Madugo observed these uncertainties do not have as much of an impact as ground motion uncertainty and accordingly PG&E has prioritized a lot of its work on ground motion attenuation models and slip rates on faults close to the plant. The geometries in the PG&E models do not impact the hazard as much as those topics and PG&E has prioritized it research based on what's most impactful to hazard. In response to Consultant Kadak's question Dr. Madugo stated concerning the uncertainties identified by the IPRP, this includes work done on the Los Osos Fault to see if it could be more of a strike slip fault. Dr. Madugo stated PG&E has looked at that through time and does not see a lot of evidence of it being a strike slip fault on shore and he agreed that offshore there are geophysics data that suggests there could be a component of strike slip, but a strike slip component has already been accounted for in the southwest vergent model and giving that model a higher weight would not have a significant impact on hazard.

            Dr Budnitz provided his view and remarked no one knows which of the three models for the uplift of the Irish Hills presented by Dr. Madugo; the outward vergent, the southwest vergent, and the northeast vergent is correct and it could be that some other model will emerge somewhere along the way that more accurately captures the situation. But Dr. Budnitz stated whatever model is proven correct and therefore worthy of 100% weight, the plant is still adequately safe and that judgment remains whichever of those turns out in the end to be right. So until research produces a resolution that either chooses among them or perhaps primes a different weight, or maybe there's new information, that safety judgment remains robust. Dr. Budnitz stated now the key question to ask about that safety judgment is whether it is true even in spite of the uncertainties and in Dr. Budnitz' judgment in this particular case as none of them produce a ground motion that threatens the plant that is significantly important compared to the ground motions that have been dealt with right along, therefore the plant's safety is not challenged by which of them is right.

            Dr. Madugo stated he organized and would address the contentions raised by Dr. Bird's work as follows: there's a thrust fault at shallow depth under Diablo Canyon with a slip rate of one millimeter a year; fault slip rates were selected subjectively in isolation; seismicity from unexpected, undetected, and subterranean ruptures is a topic; and the analog of the Noto Earthquake applies directly to Diablo Canyon and has an impact on hazard and risk.

            Dr. Madugo stated in its review PG&E considered new data methods, models, technically defensible for use in seismic specific hazard assessment, and whether the existing model captures the goal or the intent of the proponent's models, what is the standard of practice and are there other groups that do seismic hazard assessment considering the same type of data or models?

            Dr. Madugo stated relative to the first contention, despite several arguments for a thrust fault at shallow depth of a kilometer or less beneath the plant and which then comes up to the surface offshore of the plant with a slip rate of one millimeter per year, no such seismic source was included. As mentioned there are no technical reports to show the basis for this fault. He noted that the previously identified Shoreline Fault has been studied in detail and is not shown to be a dip slip or a fault that moves the ground vertically. There is also a note about a topographic scarp on the southwest side of the Irish Hills that would be consistent with this type of fault. He reported during Dr. Bird's presentation to the DCISC, a map was provided that indicates the location of this previously unidentified fault as between the coast and the Shoreline Fault.

            Dr. Madugo stated there were extensive investigations done as part of the 2011 Shoreline Fault Report including offshore, geophysics, dosimetry and in the AB 1632 studies that looked at the issue of whether there are any faults that have been missed offshore of the plant and for the faults that have been identified, are they vertical, are they strike slip, are they dip slip, are they low angle. Onshore drilling, mapping, geophysics do not show a fault at the base of the Irish Hills between the marine terraces and the hill and there is evidence to show that there are undeformed strata crossings that are a hundred thousand years or older which would indicate there is no fault located there. Evidence was found for the Shoreline Fault and the indicators are that it is a strike slip vertical fault, but no evidence has been found of a reverse fault which Dr. Madugo stated would be indicated by a large vertical scarp. He displayed bathymetry data from off the coast of Noto, Japan, where a dark line can be identified that is possibly a thirty foot high scarp on one of these reverse faults. He observed the scarp from the January 1, 2024 Noto earthquake is apparent and it is approximately two meters high and offshore of DCPP the equivalent type of data is not seen. He stated Dr. Bird is arguing not only for a reverse fault that should have expression near the surface, if it's a shallow fault, but also for a relatively fast moving fault. He remarked fast slipping would mean that it has lots of earthquakes and it would be producing these types of features, but over multiple studies and in the contentions themselves there is no evidence for this fault.

            In response to Dr. Kadak's question Dr. Madugo stated a reverse fault moves one side of the fault up relative to the other and for a really big reverse fault one would expect a basin, a big sedimentary basin, on one side and a hill on the other side, and just with a simple dosimetry the topography on the bottom of the ocean one can see that scarp in Noto, Japan, that hill has been created to a height of about 30 feet but nothing like that is seen offshore of Diablo Canyon.

            Dr. Madugo reported Dr. Bird has proposed two different ways, aside from geodesy, to assign a slip rate to that fault including looking at the throw [defined as vertical displacement] of the Obispo Formation, which is a geologic unit, over the last five million years. In a paper that Dr. Bird published in 2007 he said that slip rates over time scales of three to five million years are appropriate for hazard studies. Dr. Madugo observed the NRC, the United States Geological Survey (USGS) and others who perform seismic hazard assessment and fault development and slip rate determination consider rates that are that old not to be of high quality or relatable to current seismic hazards and PG&E concurs. The marine terrace is over a hundred thousand years old and is well defined and well dated and the offsets are well constrained. Dr. Madugo remarked PG&E has a very high quality dataset on the offsets of the faults, or the slip rates on the faults that are there and he does not understand why PG&E would need to consider a five million-year slip rate. Also, without the faults being there, and the correlations of the units across where Dr. Bird says the faults could be, that is not a unique solution. He stated PG&E does not believe that is a technically defensible slip rate unless there is a technical report that provides more information on why that would be a defensible slip rate.

            Dr. Madugo observed another way that Dr. Bird argues for high slip rates on the inferred fault is using Airy isostacy, which he described as a very technical concept, but involves the crust beneath the Irish Hills, and this model will be very weak. It postulates the Irish Hills are floating like an iceberg, with a lot of their mass below the surface and therefore any time the Irish Hills grow by faulting or other means they would have to grow by a factor of 6 below the surface. Mr. Madugo observed Dr. Bird contends that all PG&E is recording relative to those marine terraces is the rise of the growth of the hills, but PG&E is not recording that additional growth of that crustal root. Dr. Madugo stated that for this model to work, one needs a very, very weak crust without rigidity.

            Dr. Madugo reported PG&E developed a simple model, as Dr. Bird didn't provide any technical report on this or technically supporting data, to see what would be seen if this were actually what was happening at the Irish Hills. So one has a block, and it has a fault that would be similar to the inferred coastline fault, and over time as the Irish Hills grew that crustal root would be growing downward. But he stated what ultimately happens is that entire mass, even though the Irish Hills are going up, where the fault is it would be going down beneath the subsurface and he displayed a graphic showing this and stated at a minimum a basin should be seen in the area that is going down and no such basin has been observed off of the Irish Hills on either side. He remarked PG&E does not believe the model for Dr. Bird's contention is applicable at the scale of the Irish Hills as that type of model is used to explain bouyancy of large mountain ranges, like the Himalayas, not a small set of hills. He reported there is a reviewed paper from 2019 on the methodology and it concludes that, given the noted shortcoming of the local isostatic models, one must question their continued use. Dr. Madugo stated that to check if PG&E was missing anything, PG&E reached out to USGS, reviewed site specific hazard studies, other SSHAC studies, slip rate data bases including one that's in a published paper by Dr. Bird. The result of these inquiries was that no one considers this method because at the scale of hills like the Irish Hills one must assume that the crust is rigid, that it doesn't have this low rigidity. No one uses it in their models and no one is considering using it. Dr. Madugo observed any new method needs a lot of work before it can be considered and at the present time PG&E does not consider it to be technically defensible.

            Dr. Madugo quotes Dr. Bird's May 16, 2024 contention in his letter to the DCISC. The contention states that reported fault slip rates were selected subjectively and in isolation, without modern deformation-modeling (as used by USGS) to guarantee that all fault slip-rates and rates of distributed permanent deformation are self-consistent, and also consistent with geodetic velocity and stress-direction data. This is the geodetic rates on the faults and then geodetic rates of deformation between faults and he stated he would address both and commented these are determined from highly accurate stations located on the ground surface and modelers looked at how these stations are moving relative to each other to estimate slip rates or deformation on faults between those stations. These data were mentioned in the 2024 Updated Seismic Assessment and were not fully addressed in the rebuttal contentions, but given the density of fault sources near Diablo Canyon, there's low confidence that geodetic data could resolve rates in kinematics of individual faults. In an ideal geodetic model one needs to have a single fault and stations far enough away to capture the full deformation on the ground surface and relate that to deformation at depth and PG&E has low confidence in any rate that one could get from geodetic models and also, the uncertainties on these models are currently poorly understood and this further reduces confidence. Accordingly PG&E does not use geodetic slip rates directly in its seismic hazard model, but does consider them as a check. Dr. Madugo stated these are regional models, they are used by USGS, but PG&E does not believe they are useful for site specific evaluations but they are compared to PG&E's geologic rates. He stated slip rates are checked against the geodetic models that are used in the USGS model that came out in 2023 and also against their geologic model and he showed a table from the 2024 Updated Seismic Assessment that shows the slip rates for these bounding reverse faults, the Los Osos and San Luis Bay Faults, with the Los Osos Fault of 0.2 to a little over 0.4 millimeters a year which he described as fairly consistent with the geologic model and also with the geodetic model. He remarked PG&E's range captures the mean rates for the geodetic models. He stated there are three different geometry models with a range of 0.16 to 0.22 millimeters and he observed the model by Dr. Bird has a lower rate than PG&E's model.

            In his letter to DCISC Dr. Bird said that all PG&E does in its comparison is look at the Hosgri Fault and does not consider the Los Osos Fault and San Luis Bay Fault. Dr. Madugo then reiterates that he has been showing Table 5.11 from the 2024 Updated Seismic Assessment, which includes comparison of geologic and geodetic rates from the Los Osos and San Luis Bay faults, and that this may have been missed in the review of the report [by Dr. Bird].

            Dr. Madugo stated another of Dr. Bird's contentions involves seismicity from unexpected, undetected or subterranean ruptures between known faults and this was modeled based upon projections of a few decades of micro-seismicity and ignores globally calibrated relationships between long-term tectonic strain rate and tectonically higher long-term mean seismicity, which includes seismic crises.

            Dr. Madugo stated Dr. Bird is essentially saying that the standard method that PG&E used and that USGS used and that other SSHAC projects use is wrong. He remarked what Dr. Bird is promoting is part of these geodetic models which produce rates on faults and he remarked you can also get information for deformation between the faults, but he stated that at this time PG&E does not believe that this data is ready for use and the USGS agrees. He reported the USGS has stated that for the off-fault deformation portion of the geodetic model it is not clear how much of the implied rates or features are real, versus artifacts with model assumptions and approximations and accordingly USGS decided not to use this element in their model and this is consistent with recommendations of a review team. For the first time for this model, USGS had independent reviews of all the deformation models that went into their hazard model and they have geodetic reviewers, geologic reviewers and they published their reviews and concluded for the off-fault deformation the uncertainties are really high and the model results are really different and the USGS does not know exactly what is being reported and so it was dropped from the USGS model, and PG&E also does not consider it presently and has reached out to USGS to do research, to understand the uncertainties in the models, how they can be applied because as a part of the seismic scientific community Dr. Madugo observed PG&E is interested in how this data can be used to understand off-fault deformation, or the deformation between faults.

            Dr. Madugo reported what PG&E does use is a background seismicity model which looks at seismicity in the seismic catalog and uses that to develop rates of earthquakes He reported this method has been used for decades and it is understood that there are some uncertainties with this method and the model has been adjusting to account for those uncertainties and understand those uncertainties and this is the standard peer reviewed model that PG&E used and which is used by everyone else in the community. He commented at some future time PG&E may use the geodetic off-fault models, but again PG&E does not have a report that describes how to apply the geodetic off-fault deformation model, what the uncertainties are, and what they are actually recording. Dr. Madugo commented what Dr. Bird says in his presentation to the DCISC and in some of the contentions is that one of the reasons that these background models are wrong, or they're incorrect, is that they wouldn't capture seismicity from a fixed fault like the San Andreas which can produce magnitude 7 to 8 earthquakes. But Dr. Madugo observed that is not the point of a background seismicity model. For that, he stated, one does detailed work and identifies all the faults, and then the background model is used to capture anything that you may have missed. The high slip rate faults will typically have some sort of expression and one can map them at the ground surface and he displayed a map showing a fault sourced model and commented USGS and others would use the same thing.

            Dr. Madugo then stated for the Noto Earthquake, a magnitude 7.5 earthquake that occurred January 1, 2024, in Japan, in March 2024 the San Luis Obispo Mothers for Peace, Dr. Bird, and others filed a petition to the NRC saying that this earthquake is the earthquake that would happen offshore of the plant on an inferred fault that PG&E sees no evidence for and that the ground motions that happened in Japan, which were quite high and expected for an earthquake like the Noto Earthquake, would also be expected for the dipping reverse faults in the vicinity of the plant. The petitioners claim the Japanese ground motions should be applied directly to the plant, and the petitioners also claim to be able to develop a return period and risk numbers based on that. Dr. Madugo reported under the Long Term Seismic Program, PG&E looks at large notable earthquakes around the world, regardless of whether there are contentions involved, including visiting the sites to determine if there is anything that can be learned for Diablo Canyon or the rest of the PG&E system and in that effort developed a report for the Noto Earthquake which has been provided to the DCISC and is focused primarily on the geology and tectonics. He reviewed in brief the five different things PG&E looked at as including the tectonic setting, fault characteristics, seismicity, deformation patterns, and characteristic earthquakes.

            Regarding the tectonic setting, Dr. Madugo reported that Japan has a large subduction zone which experiences frequent large earthquakes. The area of the Noto Peninsula is not along a subduction zone and it is far away from that what he stated is considered a back arc basin. Dr. Madugo observed the central coast of California has quite a different tectonic environment. It has this lateral sheer and compression which he stated was discussed at the beginning of his presentation. Dr. Madugo acknowledged some elements are similar, at a very high level, because in the Noto Peninsula area, the area extended and a basin was formed and now it's contracting. There is what he termed an inverted basin and those basin deposits are being uplifted. Dr. Madugo stated that is also happening locally in the central coast area of California due to transpression, a combination of contraction and strike slip movement. He acknowledged that at the very highest level there are some similarities, but there are also a lot of differences in the tectonics of the two regions.

            Dr. Madugo reported PG&E next looked at scale of the two areas and characteristics of the fault and he displayed a map of the Noto Peninsula which he observed is much larger than the Irish Hills, with a long axis of 45 miles versus 10 miles for the highest uplifting part of the Irish Hills. He reported there are faults offshore of the Noto Peninsula, with reverse faults on the northwest that are dipping underneath the peninsula and faults on the southeast side of the peninsula also dipping the same direction and the Noto site does not have the wedge model similar to the Irish Hills and he commented this is a significant difference. Also, he stated around the Noto Peninsula there are multiple main active faults which have been shown to rupture independently or together. Dr. Madugo observed at the DCPP site there are not as many faults offshore of the Irish Hills.

            Dr. Madugo stated in terms of seismicity, since the 1990s there have been multiple greater than 6 magnitude earthquakes in the vicinity of the Noto Peninsula and these have been reverse thrust events. There was one magnitude 7, which was the January 1, 2024, earthquake. In the Irish Hills and the central coast, there has been one magnitude 6.6 earthquake and no other earthquake greater than magnitude 5 in the same timeframe.

            Dr. Madugo remarked concerning the deformation pattern, because all the faults in the Noto Peninsula or the most active ones are in the northwest side, you see this block uplift and tilting.. Whereas, in the Irish Hills, you see that block uplifting together symmetrically and Dr. Madugo stated this is why PG&E's preferred model is one where both faults do the work to uplift the hills.

            Dr. Madugo pointed out again that offshore of the Noto Peninsula there is evidence of multiple past reverse fault ruptures with one side of the fault going up relative to the other side. He reported there is a rupture from the most recent earthquake and offshore of DCPP, where this inferred coastline thrust should be according to Dr. Bird, PG&E does not see that pattern of deformation.

            In concluding his part of the presentation Dr. Madugo stated at this point PG&E does not have enough data to say whether that 7.5 magnitude earthquake on the Noto Peninsula is the characteristic earthquake. The Noto Earthquake strung together ruptures on all the faults offshore and then it extended another 30 kilometers offshore, and the aftershock pattern goes another 50 kilometers beyond that. For the Irish Hills and around the plant PG&E has considered models like that, but cannot say which one is the characteristic earthquake. Dr. Madugo stated when Dr. Bird argues that a magnitude 7.5 earthquake offshore of the Noto Peninsula is the earthquake that PG&E needs to consider on this inferred fault offshore of Diablo Canyon, PG&E has seen no basis for that argument. He remarked that it would be helpful if Dr. Bird were to provide a technical report with supporting evidence that would assist in understanding his contentions, but at this point PG&E does not think those contentions can be supported. In conclusion he stated with the tectonic settings between the two areas, there are different mechanisms and styles of deformation, the faults are different, there is a different seismic history, different regional and local uplift patterns, and there's a range of characteristic earthquakes for both areas, but the areas are dissimilar enough that you cannot take parameters from this Noto Earthquake and just substitute them for what's happening in the vicinity at Diablo Canyon.

            Dr. Kottke began his portion of PG&E's presentation by observing Dr. Bird's first contention concerns the rate of failure and Dr. Bird takes the ground motions from the Noto Peninsula event and estimates that the severe accident rate is 47 to 70 times higher. He reported the core damage frequency that Dr. Bird provided is not based on an accepted practice and, as Dr. Madugo stated the Noto Earthquake is not a direct analogy for an event off the California central coast and direct application of ground motion in this manner has not been standard practice for over two decades. He remarked when observed ground motion data is available the data needs to be corrected for site effects, source to site distance, and earthquake event terms and this established practice has been in use for a long time for hazard modeling. As a result of the ground motion data and the probability distributions that PG&E used in its seismic hazard analysis, this produced ground motions that are higher than Noto event and those are used in the fragility assessment for the plant. Dr. Kottke observed the core damage frequency estimate does not take into consideration the structural response or the fragility of the system and therefore the approximation of the hazard suggested by Dr. Bird is not founded in practice.

            In response to Consultant McWhorter's query Dr. Kottke stated Dr. Bird relates the ground motion and estimates a slip rate and amount of slip consumed by the event to come up with a return period of that event and Dr. Bird claims that given that ground shaking, damage would be certain and Dr. Kottke confirmed Mr. McWhorter's impression that Dr. Bird has based the order of magnitude of core damage frequency on the order of magnitude change of the ground motion and concluded damage would be certain. That is, Dr. Bird came up with a return period of the Noto event on an assumed slip rate and his claim is if that ground shaking were to occur, then core damage would occur. The only estimate of frequency that he provides is the rate of occurrence of the earthquake, and from that Dr. Bird claims that the earthquake is so strong, the plant would fail. Dr. Budnitz observed that in Dr. Bird's model it is not that the earthquakes are larger, it is that these large earthquakes come around much more frequently in his model.

            Dr. Budnitz remarked when the seismic community started doing seismic probabilistic assessments 35 years ago, those approximate assumptions were used as a first round of the analysis, but since then they have been superseded by much more detailed and a better understanding and those approximate assumptions are simply not used anymore. Dr. Budnitz reported in the late 1990s he was the author of a report and then participated and chaired a committee in writing an American Nuclear Society (ANS) standardized methodology for seismic probabilistic risk assessment and at that time it was recognized the use of approximate assumptions were embedded with significant errors and uncertainties.

            Dr. Kottke confirmed Dr. Kadak's observation that Dr. Bird has not done any seismic analysis of the plant itself and Dr. Kadak questioned how Dr. Bird developed his core damage number without having done a structural failure analysis. Dr. Kottke remarked there is only one sentence in Dr. Bird's report that states if the ground motion is high that high core damage must occur based apparently on direct numerical scaling.

            In response to Consultant McWhorter's question as to whether PG&E has used Dr. Bird's numbers in its model to produce a change in core damage frequency that is based on a seismic analysis of the plant, Dr. Kottke replied that to do so would not make any sense for the reasons described by Dr. Madugo and because the data Dr. Bird offers on recurrence rates are not backed by any supporting process. In response to Dr. Kadak's observation Dr. Kottke confirmed Dr. Bird's method relates to recurrence of the event versus the size of the event, and does not make a distinction in terms of the evaluation of core damage.

            Dr . Kottke reported Dr. Bird also contends that PG&E did not use a hanging-wall term for modeling the potential ground motion from Los Osos and San Luis thrust faults. He stated this is an inaccurate assertion, as Section 6.3 of the 2015 Seismic Source Characterization report developed five alternative hanging-wall factors developed from established models. He reported PG&E has considered hanging-wall factors for a long time as the issue is important not only to DCPP, but it is also important to PG&E's dam facilities and he reported PG&E funded the original hanging-wall study that was used in NGA-West 2 and PG&E has continued to invest in simulations that extend its database of hanging-wall modeling and this work continues in NGA-West 3. Dr. Kottke reported not only is PG&E using hanging-wall models in its models, PG&E is supporting and developing those models and he displayed information on five alternative branches relative to published models.

            In conclusion Dr. Kottke stated no evidence has been provided for support of the existence of the inferred coastal thrust, the novel slip rate approaches proposed by Dr. Bird have not been validated, and there are poorly constrained uncertainties that are not yet accepted by the seismic hazard community. He stated modeled PG&E slip rates for reverse faults are consistent with those using geodetic methods, including the Shen and Bird approach and the Noto Earthquake is not a direct analogy for a seismic hazard underneath the plant due to differences in geology, seismicity and scale and therefore it is not applicable to estimate core damage frequency given the ground motions and the return period of such an event. He remarked the PG&E hazard model continues to capture the center, body and range of the technically defensible interpretations and it's been reviewed at multiple levels. He remarked PG&E in its assessments has taken each of Dr. Bird's contentions very seriously and PG&E continues to work on characterizing ground motion and the source characterization near the plant and has been reviewing the use of new geologic dating methods to assess deformation style and rates in the Irish Hills with the USGS and is considering vetting and publicizing or publishing structural models for the Irish Hills. Dr. Kottke remarked this was done previously in PG&E's Seismic Source Characterization report and PG&E is looking at doing it in a more public manner with external teams.

            Dr. Kottke concluded his comments and reported PG&E is going to look at an evaluation of the Casmalia Hills regarding the dating and uplift rates and will perform further assessment of on-fault and off-fault geodetic modeling for the Irish Hills, including applicability, constraints and uncertainty. He commented PG&E is doing ongoing work on precariously balanced rock studies and continues to work on NGA-West 3, which is a new round of ground motion modeling and will be applying those results when they are prepared.

            Dr. Meshkati observed the 2024 Updated Seismic Assessment Participatory Peer Review Panel included Drs. Norman Abrahamson and Thomas Rockwell and Dr. Meshkati remarked a colleague had identified those two gentlemen as the best in the field and he further observed the external peer reviewers consisted of the B. John Garrick Institute for the Risk Sciences at UCLA which included Drs Ali Mosleh, Yousef Bozorgnia, and Ralph Archuleta and Dr. Meshkati stated he knows and respects Drs. Mosleh and Bozorgnia and he asked whether those parties would be requested to review any study PG&E performs on Dr. Bird's contentions. Dr. Budnitz responded and he observed Chapter 6 of the 2024 Updated Seismic Assessment deals with Dr. Bird's evaluation and conclusions with the sole exception of the Noto Earthquake which had not yet occurred and both peer review teams concurred with the conclusions stated in Chapter 6 concerning Dr. Bird's evaluations and conclusions which were consistent with the reports just presented by Drs. Madugo and Kottke. Dr. Kottke responded PG&E is considering a formal report documenting its response to Dr. Bird's contentions, but he remarked the contentions are set forth in many different documents and have evolved over time. He observed that a single document laying out Dr. Bird's contentions in full would be helpful in this regard. In response to Dr. Meshkati's request Dr. Kottke offered to provide Dr. Meshkati with the basis used by Dr. Bird in his work setting forth Dr. Bird's basis for connecting ground motion to core damage frequency. Dr. Budnitz reported the Committee will hear more on this topic during the afternoon session. Consultant Wardell commented he would like to hear more about the extent of peer review relative to what PG&E has done and what Dr. Bird and others have done.

            The Chair then recognized Dr. Peter Bird.

            Dr. Bird stated he wanted to begin his comments by briefly responding to misstatements about his work. He observed the first misstatement concerned PG&E's assertion that he had no basis for converting the ground motions in the Noto Earthquake to a certainty of core damage at DCPP. He stated his basis for the conversion was stated very clearly in his declaration to the NRC, and it is the 2018 Seismic Probabilistic Risk Assessment (SPRA) published by PG&E and accepted by NRC. Dr. Bird reported there are tables in that report which show the likelihood of core damage at various levels of spectral acceleration and this provides a firm basis for his conversion.

            Dr. Bird stated a second misstatement concerned mention of the Shannon/Bird published model showing rather low slip rates on the stress faults which PG&E recognizes around the site. He remarked that while technically true, it's seriously misleading. He reported the published model, as required by his and Dr. Shannon's contract with USGS, requires the use of both geologic slip rates and geodetic data. He stated the geodetic data in the area of Diablo Canyon were rather weak because PG&E has not released the velocity that it has measured at the site. Therefore, the result was largely dictated by the geologic slip rate and if one looks at the geologic slip rate in the fault and fold database, that data comes from PG&E and they are based on PG&E's very questionable steep dips for those two faults. Dr. Bird remarked that while it is technically true that that report showed low slip rate, it is purely an "echo chamber effect" and does not represent new information.

            Dr. Bird stated he would not address some omissions from today's presentation by PG&E. On the subject of whether we know all the important stress faults under the Irish Hills, he stated PG&E first omitted, when his inferred coastline thrust fault was presented, to mention that he has maintained it is probably a blind thrust fault.[9] That is, it probably terminates at the base of the Obispo formation or somewhere about that level producing a forced fold. He stated the southwest topographic slope of the Irish Hills is that fold, and the extreme definition of bedrock that is seen right in the foundation of the plant is deformation associated with that forced fold.

            Dr. Bird stated a second serious omission was PG&E not addressing his point that the bedrock under the sedimentary rocks of the Irish Hills is the Franciscan Complex which is basically made of thrust faults consisting of thin sheets of oceanic sediment, continental sediment and ophiolites and such that were stacked up during the subduction of the Farallon Plate in the cretaceous and early tertiary times. Dr. Bird observed any one of those faults could continue to be active or could be reactivated and the fact that we have no evidence about the location of those faults or their hazards is representative of the principle that lack of evidence is not evidence of lack.

            Dr. Bird observed on the question of the slip rate in the Irish Hills region broadly that PG&E has attempted to create a false controversy about whether there is isostasy in the Irish Hills and to assert the Irish Hills have a crustal strength that would preclude isostasy. Dr. Bird claimed this assertion can be disposed of using PG&E's own data published in the 2024 Updated Seismic Assessment that includes an updated isostatic gravity map of the Irish Hills which shows that not only are the Irish Hills compensated by crustal root, but the crustal root is actually larger than you would predict from a simple isostatic area calculation, Therefore, he stated the factor of six that he used to convert from uplift rate to crustal thickening rate was actually probably a bit too small, but he remarked we don't know exactly how much too small.

            Dr. Bird stated he already alluded to the question concerning the net rate of thrusting in the Irish Hills if we knew the rate of crustal shortening across the Irish Hills in the horizontal direction. He commented PG&E has in its power to resolve that question by releasing their GPS velocity data from Diablo Canyon and any adjacent sites on the southwest side of the Irish Hills but has chosen not to do so.

            In concluding his comments, Dr. Bird stated he would speak to the question of the applicability of the Noto Earthquake. He observed it was pointed out that the Noto Earthquake is part of the Japanese Arc[10] that was created adjacent to a subduction zone. Dr. Bird observed the coast of California was engaged in a subduction zone in cretaceous and early tertiary time up to 28 million years ago. The same rocks are present in both places and the same structures are present in both places, and that is why it's a reasonable analog. He remarked the fact that the Irish Hills have a lower seismicity than the Noto Earthquake site is very natural because the Noto Peninsula is in the middle of the seismic crisis, and currently the Irish Hills are not, but he stated one has to look forward and consider the possibility that the Irish Hills may in the future be engaged in such a seismic crisis.

            Dr. Bird thanked the Committee for the opportunity to make his comments.

            The Chair thanked Dr. Bird and stated it would be highly valuable if this could be documented in the form of a report that could then be subject to review.

            Dr. Madugo reported PG&E is in the process of developing a memorandum on Airy isostasy which he described as a very technical topic. In terms of the geodesy and the GPS stations, Dr. Madugo reported PG&E does not run those stations which are run by USGS. PG&E funds the USGS to run those stations, including one at the plant or in the vicinity of the plant. Dr. Madugo reported the USGS is not allowed to act as a consultant to PG&E or anyone, so the data that USGS generates has to be publicly available and the data from the semi-permanent and the continuous stations and the campaign stations, which are visited from time to time, are available online at the USGS site. Dr. Madugo stated he recently reviewed the USGS website for these stations and those data are available and were used in the geodetic model for the USGS seismic hazard assessment so Dr. Madugo said he is not certain what Dr. Bird meant when he stated the data are not available.

            Dr. Madugo commented that in terms of modeling those data, PG&E has not yet developed new models and he mentioned there are multiple reasons why PG&E believes there are issues with modeling geodetic data at a coastal site. He remarked a lot of the faults are offshore where there are no stations. He reported PG&E has talked with USGS about undersea stations, whether those are feasible and they are but they are very expensive and it would take decades to get information on the low slip rate faults that PG&E is looking for but it has been considered. Dr. Madugo commented PG&E is in the process of determining with geodetic experts what modeling could be done to provide some sort of meaningful constraint given the limitations of all the faults in the vicinity, the limited number of stations at a coastal site, and as part of the DCPP Long Term Seismic Program PG&E talks with USGS regularly.

            Dr. Madugo observed with reference to the Franciscan Complex Dr. Bird mentioned during his presentation, in some of Dr. Bird's contentions Dr Bird has said because there are all these shallow dipping ancient faults in the Franciscan Complex, those are the most likely active faults to host large earthquakes and Dr. Madugo stated PG&E disagrees. Dr. Madugo stated in his presentation he tried to point out the San Simeon example where Dr. Bird's preferred dip for faults in Franciscan is 25° and none of the data from the San Simeon Earthquake occurred on faults that were dipping 25°. They were all more than 25°, and most of them were in the 40°, 50°, or higher range, and so this is the impossible range that was mentioned by Dr. Bird in his contentions. He commented there is other data to support the steeper dips as well in other models.

            Dr. Madugo observed that in terms of the surface expression of Dr. Bird's inferred coastline thrust, a deep line thrust would still have some sort of surface expression while a shallow line thrust would have much more of a surface expression. But he reported Dr. Bird is arguing that the folding in the bedrock of the Irish Hills is reflecting that shallow thrust. But he commented PG&E does not see tilting of the 100,000 year old marine terraces or the offshore coastal platforms like was seen at the Noto Peninsula. At the Noto Peninsula the faults came up to the surface, but if those ruptures died out below the surface, instead of seeing a sharp scarp one would see a broad scarp and PG&E does not see that reflected in much younger data than that ancient, folded rock and does not see it where those terraces wrap around the Irish Hills. The Irish Hills are intensely folded by older bedrock, but the terraces aren't folded at all and this is why PG&E argues for block uplift, no significant thrust fault that's deforming.

            Dr. Budnitz reported the DCISC met with Dr. Madugo and his colleagues at the end of August 2024 and received PG&E's interpretation of the Irish Hills as being bounded on the north side by the Los Osos Fault and on the other side by another fault and Dr. Madugo showed figures today that those two faults in PG&E's interpretation provide the extent of the Irish Hills. So the Irish Hills cannot be, for example, 50 miles in extent because they're bounded in that way and at that meeting PG&E explained that its interpretation was that that bounding limited the amount of the length of a fault that might get one into trouble under the Irish Hills and how much energy it could develop because it's related to how long it could be, and that it is shorter than would support such a large motion. Dr. Budnitz commented he read the 2015 Seismic Source Characterization study about that issue and then read what was touched on in the 2024 Updated Seismic Assessment. He asked if Dr. Madugo could explain whether and how firm that evidence is for eliminating the very high possibility of a much bigger feature there in the Irish Hills. Dr. Madugo replied and said first in terms of lower angle thrusts that could dip down to 35°, that's in PG&E's background model to account for some slippage on those plains in the Franciscan, and in terms of the extent of the main bounding fault one is talking about length. He remarked what PG&E is really interested in concerning what Dr. Budnitz was referring to, is the width of the fault going from the surface down to the base of the seismogenic zone, which is 12 kilometers deep. Dr. Madugo stated PG&E did consider other models including the model that Dr. Bird shows in his cross sections with a very low angle fault going down and passing beyond the surface expression of the Irish Hills. But Dr. Madugo observed it would run into other faults and PG&E sees no evidence of a fault doing that and does see from the San Simeon Earthquake that the faults that were involved did not extend beyond the extent of that surface expression of the hill. He stated the Noto Earthquake is useful in some aspects and although one cannot take the exact characteristics of that earthquake and apply them to Diablo Canyon it can inform PG&E's model as when one looks at all the seismicity, there are aftershock patterns in big earthquakes and they have all occurred on faults that don't extend beyond the Noto Peninsula and one does not have very low angled faults in a similar type of bedrock extending at 25° beyond the extent of the Noto Peninsula. He reported all the dips are higher than 30° with some in the 50° range, but all those widths do not extend beyond the Noto Peninsula which supports some of PG&E's modeling decisions.

            Dr. Bird stated he is aware of PG&E's argument that basically one cannot reproduce the Noto Peninsula rupture under the Irish Hills because the Irish Hills are too small, but his response to that is that the shaking at the plant is not primarily determined by the length of the rupture, it is primarily determined by the stress drop immediately underneath the plant. That is, how fast the fault slips and how far it slips immediately underneath the plant and for that reason Dr. Bird stated he would contend that in fact the actual seismograms from the Noto Peninsula Earthquake should be used in modeling and if the industry standard is to exclude those then the industry standard is corrupt.

            Dr. Budnitz stated his understanding of Dr. Bird's comment is that Dr. Bird's believes that the stress drop is significantly larger and it overrides what would otherwise be the geometrical constraint because of the width of the Irish Hills. Dr. Bird stated magnitude is not everything and he agreed with Dr. Budnitz statement.

            The Chair stated the Committee would at this time adjourn for lunch and will return to the same topic area during the afternoon session and members of the public will have the opportunity to make comments at that time.

V         ADJOURN MORNING MEETING            

            The Chair adjourned the morning meeting of the DCISC at 12:10 p.m..

VI        RECONVENE FOR AFTERNOON MEETING

            The afternoon meeting of the DCISC was convened by the Chair at 1:15 p.m.

VII      COMMITTEE MEMBER COMMENTS

            There were no comments by any member at this time.

VIII     PUBLIC COMMENTS AND COMMUNICATIONS

            Dr. Peterson invited members of the public to address the Committee on matters not on the agenda for this meeting.

            Dr. Gene Nelson representing Californians for Green Nuclear Power was recognized. Dr. Nelson stated he recently wrote to the NRC in response to the 10 CFR 2.206 Petition filed by San Luis Obispo Mothers for Peace. He read from a section of his letter wherein he stated his disagreement with the assertion by Dr. Bird that there were significant similarities between the setting of the Noto Peninsula in Japan and DCPP. Dr. Nelson's letter stated that during the largest earthquake near the site of DCPP, the 2003 San Simeon Earthquake with the epicenter located approximately 20 miles north northwest of DCPP which ruptured to the southeast for 20 miles, DCPP operations were unaffected and the plant continued to operate at full power. Dr. Nelson stated that essentially all the active earthquake faults in the immediate vicinity of DCPP are strike-slip.

            Ms. Diane Curran, an attorney for Mothers for Peace was recognized. Ms. Curran stated her concern with an apparent lack of transparency by the DCISC based on the meetings held with PG&E in August and September of 2024 to discuss Dr. Bird's work to which neither Dr. Bird or a representative of Mothers for Peace were notified or invited. Ms. Curran observed there have been at least two written reports provided to the DCISC by PG&E of which her clients were unaware and she requested to be provided with any written reports provided by PG&E to the DCISC which the DCISC is considering in its deliberations. Ms. Curran commented Mothers for Peace were unaware the GPS data which is of concern was publicly available and she requested a reasonable opportunity to respond to that significant information. Ms. Curran closed her remarks with the request that if there are further deliberations that the Mothers for Peace and Dr. Bird be included.

            Drs. Peterson and Budnitz and Assistant Counsel Rathie responded and reported that when the DCISC routinely meets with PG&E or other parties in fact finding only one DCISC member together with one or more consultants is present and participates and therefore there is not a quorum such that the meeting would constitute a public meeting requiring notice and the opportunity for the public participation. The authorship of the fact finding reports remains with the member and consultant until the report is presented and approved by the Committee at a public meeting. Fact finding reports are made publicly available on the Committee's website www.dcisc.org prior to each public meeting. In response to Ms. Curran's observation that an invitation to Dr. Bird would not have violated the Committee's fact finding protocol, Dr. Budnitz replied the Committee often meets with PG&E to discuss reports prepared by others and in this case the purpose of the meeting was for PG&E to address questions posed by Dr. Budnitz.

            Ms. Linda Parks, who identified herself as a member of Mothers for Peace, was recognized. Ms. Parks stated she would appreciate access to the DCISC fact findings. Ms. Parks stated her concern was with previously uncharacterized thrust faults beneath DCPP and the lack of validation of the existence of such faults. She remarked she is concerned the issues raised by Dr. Bird are not being reviewed and she appreciates the concept of having a peer review of Dr. Bird's report and suggested this might be done by the same individuals who reviewed PG&E's report and she observed as the Noto Earthquake occurred after PG&E's report was peer reviewed there was no ability to determine if an equivalency exists between Noto, Japan, and DCPP. Ms. Parks remarked when one speaks in terms of structural damage caused by seismic events when the structure is a nuclear plant one does not see the effects of radiation that can spread for hundreds of miles. She encouraged the DCISC to look at unbiased consultants' reports of Dr. Bird's work by persons not paid by PG&E and commented his claims as to a possibility of core damage being much greater and Dr. Bird's professional credentials warrant the DCISC's review.

            Ms. Linda Seeley of Mothers for Peace as recognized. Ms. Seeley asked the members of the DCISC to think about whether they would endorse building a nuclear power plant where DCPP is now located knowing today that there are at least four active earthquake faults and other faults in the vicinity. Ms. Seeley said she read an article by Mothers for Peace expert the late Mr. Dave Jackson who claimed the most powerful earthquakes in history occurred on faults that were not located.

            PG&E Senior Director Tom Jones was recognized. Mr. Jones observed that SB 846, which modified the California Public Resources Code, was quite vague and lacked specificity as to the requirements for PG&E to conduct and update its seismic assessment as a covenant of the contract between the DWR and PG&E. He observed this made the task challenging for PG&E and PG&E explored with the Independent Peer Review Panel (IPRP)[11] developing a consensus around PG&E's approach to doing the work required by SB 846.

IX        INFORMATION ITEMS BEFORE THE COMMITTEE (Cont'd.)

            Dr. Peterson requested Dr. Gordon Seitz of the Independent Peer Review Panel and the California Geological Survey to make the next presentation.

            Dr. Seitz reported he has worked with the IPRP since 2011 and the focus of his research is on seismic source characterization. Dr. Seitz observed the Hosgri Fault is the primary source for seismic hazard at the DCPP site and he reported the slip rate for the Hosgri has increased based primarily upon one study for which he reported there is now much greater confidence due to several research papers published since the 2015 Seismic Source Characterization report.

            Dr. Seitz stated there are four sites used by PG&E to estimate the slip rate on the Hosgri Fault, those being the San Simeon, Point Estero cross-Hosgri, Southern Estero Bay, and Point Sal sites. Dr. Seitz commented the IPRP agrees with much of the 2024 Updated Seismic Assessment, however, the IPRP disagrees with how the slip rate was weighted in the final determination for the entire slip rate for the Hosgri Fault. He reported the cross-Hosgri slope study at Point Estero has the highest weight now and had a lower weight in the 2015 Seismic Source Characterization but with the new confidence the slip rate used at a higher rate is 2.6 millimeters (mm) per year, plus or minus 0.8 mm. Dr. Seitz described the data as consisting of an offset marker that has been dated by several sediment cores using two different methods, those being by radiocarbon and by optically stimulated luminescence to produce a well-defined slip rate close to DCPP.

            Dr. Seitz stated the key is the weighting of the four slip rate sites and the IPRP agrees there is greater confidence now than in 2015 the geological interpretation of the site is correct and that the slip rate from the site is a reliable estimate of the slip rate for the Hosgri Fault near the plant. He reported one measures the age of the feature and the distance it has been displaced by the fault, the location of the slip rate site in proximity to DCPP, and the confidence that the interpretation of the site provides toward a reliable result. He displayed and described a table summarizing the data for each of the four sites he identified including the San Simeon site which he stated is not well defined and is a complicated feature some 200,000 years old and was weighted in 2015 at 30% and in the 2024 Updated Seismic Assessment at 25% with a slip rate of 1.8 mm. The Point Estero cross-Hosgri site is unique in that it is 12,000 years old which he stated is the best age for determining the hazard today and its weighing has gone from 20% in 2015 to 50% today. Dr. Seitz remarked all these sites are fairly close to DCPP except for Point Sal and confidence is high for each. He commented that for all four sites the slip rate is considerably higher at the cross-Hosgri slope and he stated this is a concern for the IPRP as the Southern Estero Bay and Point Sal sites are 700,000 years old which is not well defined and dated by correlation and thus have lower weight. He referred to a NRC contracted independent evaluation of the Hosgri Fault slip rate based on a structural analysis of the Pull-Apart Basin[12] linking the Hosgri and the San Simeon fault systems that was not considered in the 2024 Updated Seismic Assessment which looked at unconformities in the subsiding basin and correlated to unconformities to sea level stand which determined the slip rates were low at less than 500,000 years while today the slip rates have increased dramatically and he commented if that is the case then using an older slip rate is not representative of the current hazard. Dr. Seitz referred to the two offsets, Southern Estero Bay and Point Sal, at 700,000 years old which he stated lack detail in how the unconformities offshore were modeled and he reported there is detail in the 2015 Seismic Source Characterization but the issue in that report is one that can only be addressed well when one has angular unconformity relationships and accordingly there is a lot of uncertainty, but the takeaway is that the slip rates in the NRC-contracted independent evaluation were much slower in the past and then increased.

            Dr. Seitz commented when one looks at what the slip rate is for the different sites, the one the IPRP has the highest confidence in is the Point Estero cross-Hosgri slope and he displayed a graph showing the cumulative probability against the slip rate for the 2015 Seismic Source Characterization and 2024 Updated Seismic Assessment and the Point Estero cross-Hosgri data. He stated the IPRP believes a better representation of the data would be the full rate of the Pont Estero cross-Hosgri slope as shown on the graph and even though it has been upweighted from 20% to 50%, half of the 2024 Updated Seismic Assessment estimate is based on data the IPRP does not believe to be technically defensible because it is too old and not representative of the current tectonic regime. In response to Dr. Kadak's inquiry Dr. Seitz stated one can imagine all the tectonic blocks in California are like pieces in a puzzle and they move and then get locked up and new faults form and therefore the lifetime of a fault is not infinite. He observed most faults in California are not active and while certain faults may look very dramatic they are not moving. He remarked it gets difficult when one sees old faults that have an orientation similar to active faults because then you cannot use the orientation as the criteria to know if they are moving. He remarked the IPRP has separate data to show that in the past it appears the Hosgri Fault was moving slower. He commented the biggest primary seismic source near DCPP is the Hosgri Fault and it is a big regional fault that can generate large magnitude earthquakes, but the Hosgri Fault is not as long-lived as the San Andreas Fault and it is still evolving and the possibility that its slip rate is changing needs to be addressed.

            Dr. Seitz commented there is a bit of a legacy bias in the way data is looked at because in 2015 the situation was different. There were four slip rate sites and only one had an initial study published, but it wasn't dated or well characterized. Now there are two more publications and the Point Estero site is well characterized and well dated and this has caused the other three to lose value and there is now new data to show the slip rate was slower in the past and is no longer representative of the current hazard. He stated there may be a feeling that these three sites need to be weighted in some manner but the IPRP would say no because it does not believe the other three should be included in any weighting scheme.

            In summary Dr. Seitz stated the IPRP agrees with PG&E that the cross-Hosgri slope slip rate best represents the hazard on the Hosgri Fault, however, the slip rate sites used appear unrepresentative of the current rates of tectonic deformation and bias toward the 2015 Seismic Source Characterization model appears to be part of the reason. He stated the IPRP believes that the cross-Hosgri slope slip rate should receive full weight in the seismic hazard model. He reported if one looks at the geodetic model it also more closely matches this slip rate determination. He described the geodetic model as akin to a decade long measurement of fault slip rates so that would make sense that they are also more closely representative of the current seismic hazard.

            Dr. Peterson introduced Dr. Philip Johnson, a geologist with the California Coastal Commission and a member of the IPRP to make the next presentation.

            Dr. Johnson displayed a map showing what he described as the unique region of the coast ranges where DCPP is located, with the Hosgri Fault located to the west of the power plant. He observed most of the faults are very much northwest striking with a more westerly trend and uplifts. He pointed out the location of the Irish Hills and the Casmalia Hills to the south and stated these form the scene for the IPRP review of the tectonic setting and the seismic hazard. He explained the Los Oso Fault is on the north side of the Irish Hills and extends offshore to where it meets with the Hosgri Fault. On the south side of the Irish Hills there are a series of faults including the San Luis Bay and Wilmar Avenue Faults which is referred to as the South Boundary Fault System. He remarked the Casmalia Hills have the Casmalia Fault on the north side and the Lion's Head Fault to the south and further south there is an east-west trending fault system which Dr. Johnson remarked rotated into place and created a greater north-south impression.

            Dr. Johnson stated the current dataset is not adequate to distinguish between competing fault geometry models for the Irish Hills and the Los Osos Fault and there exists uncertainty as to the slip rate. He stated offshore data may be productive in this regard and the IPRP is hoping offshore investigation will be pursued. He stated the vertical uplift on the Los Osos Fault is relatively small but there is potential for lateral slip. He displayed a map of the area offshore of the Los Osos Fault which he stated shows some indications of vertical strike slip faulting offshore and he observed the assumption has long been that the Los Osos Fault is a reverse type fault and he commented if it is strike slip that this changes the calculation. He reported the marine terraces that can be traced around the Irish Hills are 100,000 years old and the uplift rate is 0.1 to 0.12 mm per year and if the faults bounding the Irish Hills are purely vertical slip there is good data on the uplift of the Irish Hills and the seismic hazard would not be as great, but if there is considerable lateral slip on these faults the hazard would have to be upgraded. He stated the IPRP will be recommending that additional offshore seismic reflection data be collected to characterize the fault zone and potentially quantify rates of lateral slip on the Los Osos Fault as well as looking at offshore from the Casmalia Hills and he stated this would provide two good hypotheses to test, that is, very little lateral slip means the hazard is relatively low, however if there is a great deal more lateral slip than previously thought the concern about the Los Osos Fault is greater.

            Dr. Johnson, in response to Dr. Peterson's comment confirmed that a proposal to perform high energy seismic reflection measurement was made some time ago which was denied due to the potential impact on marine species, but the IPRP will be proposing use of low energy seismic reflection techniques that have been very successful with investigation of the Hosgri Fault and has proven itself as effective in looking at sediments close to the surface. He remarked low energy reflection is not very effective to look deeper and he commented he did not believe the California Coastal Commission would approve the use of high energy investigative technique due to the impact on aquatic species. PG&E Senior Director Tom Jones confirmed the high energy techniques PG&E applied for were rejected by the Coastal Commission and the cutoff was given as 2,000 joules of energy. He reported complete low energy testing was performed in the region in 2013 and 2014. Dr. Seitz observed low energy techniques produce a much higher resolution and have gotten much better in the last 15 years. Dr. Kottke stated low energy investigative techniques have proven to be very effective for the Hosgri cross-slope work and this work was funded by PG&E. As part of that work USGS suggested doing preliminary work using low energy techniques along the Los Osos Fault and there was evidence of strike slip and reverse faulting found, but this preliminary work has not been published in an official paper but has been presented to the IPRP. In response to Consultant McWhorter's question Dr. Seitz stated that these efforts to refine the understanding of the seismic hazard have the potential to significantly change the seismic hazard. Dr, Seitz commented the update on the slip rate for the Hosgri Fault moved on the order of 20% by the 2024 Updated Seismic Assessment and could potentially move another 20% higher. Dr. Seitz stated the change in the ground motion response spectrum (GMRS) from between 2015 and the 2024 Updated Seismic Assessment increased by approximately 3% and he commented this could increase by 6%. Dr. Budnitz remarked that in his presentation later today he would be providing an explanation on his evaluation of the significance of such an increase.

            Dr. Johnson next discussed data that was not included in the 2024 Updated Seismic Assessment including work on the Casmalia Fault performed by Dr. Nathan Onderdonk and Dr. Ian McGregor in 2021 on the Orcutt Formation which Dr. Johnson described as a very young sedimentary unit related to the Casmalia thrust fault which gave a slip rate of 5.6 to 6.7 mm per year for the Casmalia Fault. Dr. Johnson reported the IPRP is recommending that PG&E conduct a comprehensive review of all fault studies in the region surrounding DCPP performed within the last ten years.

            Dr. Johnson reported members of the IPRP have met with members of PG&E's Geosciences Group and the meeting was productive and allowed for clarification of portions of the IPRP's report and he observed continued discussions should be fruitful. He commented PG&E may need additional time over the IPRP's timeline to respond to the IPRP's report.

            In response to Dr. Meshkati's inquiry Dr. Johnson reported the tsunami hazard comes from offshore landslide activation during any earthquake or from a far traveled tsunami occurring from a subduction zone area such as the Cascadia Subduction Zone in northernmost California, Oregon and Washington. He replied the IPRP has not delved into a tsunami analysis in context of its current review but will be looking at it more in the future. He remarked there have been preliminary studies offshore of the Los Osos Fault and with additional work, information on paleo shorelines that could be offset would reveal additional information on lateral slip on that fault. Mr. Bachhuber confirmed PG&E has periodically performed a series of tsunami evaluations, with an update in 2024 which does consider nearby offshore faults and submarine landslides as well as large events from Alaska and Japan. Mr. Bachhuber reported the evaluations show that DCPP has sufficient freeboard between the safety related plant components for even the highest extreme tsunami event. He observed the DCPP evaluations are more conservative than the State's tsunami models

            In response to Consultant Kadak's inquiry Dr. Johnson replied that there were some fault studies performed in the last ten years which PG&E did not review in the 2024 Updated Seismic Assessment and the IPRP wants to make sure any relevant regional fault studies, such as that by Drs. McGregor and Onderdonk, are included even if the impact to DCPP is negligible. Mr. Bachhuber stated in 2015 PG&E did sensitivity studies for what seismic sources affect DCPP and he reported more than 90% of the hazard was from primary fault sources and background sources, minus the San Andreas Fault which contributed 2-3%, in the aggregate, contributed 1% to the hazard. He reported in those studies Casmalia Fault was discussed but at the time it was decided not to do an in-depth evaluation because it was not hazard significant, even if the slip rate on the Casmalia Fault increased to 5-6 mm per year the distance from DCPP precludes a significant hazard increase.

            The Chair called for public comments related to presentations by Drs. Seitz and Johnson  

            Dr. Gene Nelson of Californians for Green Nuclear Power was recognized. Dr. Nelson commented Dr. Johnson referred to the work of Drs. McGregor and Onderdonk and gave a reference [to the Casmalia Fault slip rate] of 5.6 to 6.7 mm per year and he stated he understood the cross-Hosgri slope to have a rate of 2.6 mm per year and the San Andreas Fault of 4.8 cm per year and he commented the reference Dr. Johnson gave seemed like an outlier, Dr. Seitz responded and stated the San Andreas Fault moves close to 30 mm per year and one cannot compare rate estimates as you have to look at the whole structure of the fault. He commented the Casmalia Fault study has been peer reviewed and cannot be dismissed.

X         CONSULTANT REPORT & RECEIVE, APPROVE, AND AUTHORIZE            TRANSMITTAL OF A FACT FINDING REPORT TO PG&E

          

A.        The Chair requested Consultant Mr. Wardell to provide a summary report on the August 27-September 24-25, 2024, fact-finding visit with Dr. Budnitz. Dr. Budnitz and Mr. Wardell reviewed the topics discussed with PG&E during that visit as follows. He stated Dr. Budnitz would be presenting the first two topics:

→        Recent Report by IPRP and its Implications for Site Seismic Hazard – Dr. Budnitz reported that with Consultant Wardell on September 25, 2024, the DCISC Fact Finding Team (FFT) met at the plant with the PG&E Geosciences Group and they discussed the IPRP's most recent report, Report #16 entitled "Initial Review of the PG&E February 2024 Updated Seismic Assessment" which was issued by the IPRP on August 26, 2024. He reported the FFT agreed with each recommendation for additional data gathering made by the IPRP in its report.

The topics selected by FFT for review included an IPRP recommendation concerning the Hosgri Fault slip rate, IPRP comments concerning uplift of the Irish Hills, and IPRP comments on using the Casmalia Hills as an analog or as a connecting fault to the Hosgri system.

            Dr. Budnitz reported the IPRP recommends giving 100% weight to one of four data sets as discussed at this meeting by Dr. Seitz and PG&E does not agree with this recommendation. Dr. Budnitz stated it is important to know that whatever the slip rate is among the options, the understanding of the overall seismic safety of the plant is not affected because the plant's seismic safety is adequate with significant margin. He observed if 100% weight is given to one model that means the earthquakes at issue will come around more frequently than with previously models, possibly 20 to 25% more frequently. He commented the GMRS may be a 3 to 5% greater but this is uncertain. But the plant has margin such that it can survive earthquakes twice as large and the frequency increase is still in the range of 10^-4 or 10^-5. Dr. Budnitz stated his evaluation was that the safety of the plant is not much affected by a change in the slip rate because the seismic safety risk is acceptably low and even if one accepts the higher range of frequency the plant remains seismically safe. He reported concerning the motion produced by a seismic event that the motion propagates through the soil and into structures and certainty in the loads produced isn't known within 10% but the plant remains safe.

            Dr. Budnitz stated he reviewed the 2015 Seismic Source Characterization and the IPRP's statement about uncertainty in the best models concerning the uplift of the Irish Hills. He observed Dr. Madugo identified three different models with differing implications. This has to do not only with the geometry, but also the slope and the rate and Dr. Budnitz stated he agrees that further research and analysis is required to resolve the issue. But he observed that whichever model is correct, the plant has adequate margin because effect of the motion produced by those different configurations on equipment damage do not differ very much and not to a degree that is significant.

            Concerning the Casmalia Hills, Dr. Budnitz stated his belief the IPRP is correct that this area located to the south of the plant could be a useful analog to the Irish Hills. He commented the Casmalia and Hosgri Faults could be linked. He reported PG&E believes that while active research is underway the understanding is too premature to provide useful enough information to support a modified model of the Irish Hills. Dr. Budnitz remarked while he agrees, it does not appear that even the most pessimistic interpretation and its implication would challenge the current overall conclusion about the adequacy of the plant's safety.

            Dr. Budnitz remarked while the IPRP Report provides valuable insight there is nothing in its recommendation that challenges the overall safety of DCPP. But Dr Budnitz added there is a significant caveat in this conclusion as the IPRP Report does not address Dr. Bird's contentions. Dr. Budnitz observed that if Dr. Bird is correct then there is a significant safety challenge. Dr. Budnitz reported a very comprehensive evaluation of the entire seismic safety understanding of the plant was developed and approved by the Committee last year which concluded the plant was safe with a lot of margin. However, this evaluation did not include Dr. Bird's concerns because they had yet to be analyzed carefully.

→        Meet with PG&E Geosciences Group in Oakland on August 27, 2024 – Dr Budnitz stated with Consultant Wardell the FFT attended this meeting with PG&E's Geosciences Group. Dr. Budnitz attended in person while Mr. Wardell listened in remotely from another location. Dr. Budnitz reported this meeting focused on seven matters raised by Dr. Peter Bird on which Dr. Budnitz stated he needed to more fully explore or understand. He reported the DCISC concluded in May 2023, based on engineering analyses, that the seismic safety achieved by the plant was fully adequate and acceptable and in response to the mandate of SB 846 requires no additional upgrades or other changes for extended operations and that conclusion was reiterated by the Committee in June 2024. Dr. Budnitz commented the DCISC is again revisiting this conclusion based on its evaluation of Dr. Bird's analysis. He then discussed those issues as follows:

            â—? The Noto Earthquake – the PG&E representatives presented several reasons why treating information from the Noto Earthquake as directly applicable to DCPP is inappropriate and Dr. Budnitz stated Dr. Madugo discussed these earlier in his presentation. Dr. Budnitz reported Science magazine recently published two articles on the Noto Earthquake which were peer reviewed and these articles do not challenge the current understanding and do not support Dr. Bird's assertion that the Noto Earthquake is an analog. However, he acknowledged that investigations by experts are ongoing and as new insights emerge the DCISC will review them to see if they challenge the current understanding.

            â—? Geodetic and velocity modeling and why geodetic based deformation models are useful but not determinative and should not replace universally used geological slip rate models. The PG&E representatives expressed that in their opinion complex geodetic models are not mature.

            â—? Seismicity from unexpected or undetected ruptures between known faults including a thrust fault under DCPP with a slip rate of approximately 1 mm per year. The PG&E representatives explained they do not believe that wide area or global models are appropriate as site-specific analysis for the coast of California is required and wide regional models are not applicable. The issue of a thrust fault under the plant was addressed in the 2011 Shoreline Fault Report which was peer reviewed and accepted by the NRC. Dr. Budnitz reported using offshore data there was no evidence found of significant thrust or reverse faulting in the wave cut platform.

            â—? Use of micro seismicity rates under the Irish Hills. Dr. Budnitz reported this approach has not been found to be a reliable way to define fault plains as it ignores background sources.

            â—? Applicability of information going back a few million years, Dr. Budnitz reported this issue was just explained by Dr. Seitz in his presentation as to why such information should not be given much weight. The PG&E representatives confirmed much of their research supports that there has been a lot of evolution. Dr. Budnitz observed the fact the tectonic environment today is not the same as then does not mean the information should be discarded but it should be used judiciously.

            â—? Dr. Budnitz observed Airy isostacy hypothesizes that the Irish Hills are floating, similar to an iceberg at sea, and changes require adjustments. The PG&E representatives explained the model of the Irish Hills uplift is not consistent with the understanding of their origin and development and using isostacy principles to calculate fault slip rates is not credible.

            Dr. Budnitz stated he has not found any reason to question the adequacy of the seismic safety of DCPP as nothing in any of the new information changes the broad understanding that there is a lot of margin in the plant's design. He stated since Dr. Bird first advanced his set of explanations, evaluations and data more than one year ago it has been reviewed by numerous persons and to date no one has agreed with Dr. Bird's position. Dr. Budnitz stated he retains an open mind but he bases his conclusions in part on the lack of support in the community for Dr. Bird's position, on his own research and knowledge and from what he has heard from PG&E representatives.

            Dr. Budnitz reported when PG&E developed the 2024 Updated Seismic Assessment the Noto Earthquake had yet to occur but PG&E devoted an entire chapter, Chapter 6, in the 2024 Updated Seismic Assessment to addressing each of Dr. Bird's concerns except the Noto Earthquake and he observed the 2024 Updated Seismic Assessment was peer reviewed by some of the world's most prominent experts, none of whom agreed with Dr. Bird.

            Dr. Budnitz remarked he has found no reason to question the adequacy of the seismic safety of DCPP because none of the interpretations he has seen so far challenge the conclusions that the plant is strong enough and the earthquakes that matter do not come around frequently enough or are of a size to challenge plant safety. He observed the DCISC should continue to review any new seismic related information that may be forthcoming concerning Dr. Bird's evaluations including information from the NRC, from the IPRP and from PG&E or anywhere else. Dr. Budnitz stated that his conclusion, which he recommended the Committee adopt, is there is nothing that has the credentials and the backup to change the broad understanding that the plant is adequately safe against earthquakes.

            The Chair asked for public comment on Dr. Budnitz' presentations.

            Ms. Linda Seeley was recognized. In response to Ms. Seeley's query Dr. Burnitz confirmed the article in the magazine Science made no comparison between the Noto Earthquake and Diablo Canyon and he confirmed his statement that the two peer review teams for the 2024 Updated Seismic Assessment, including the chapter on Dr. Bird's contentions which did not include Dr. Bird's assessment of the Noto Earthquake, did not agree with Dr. Bird's position and the 2024 Updated Seismic Assessment provides an evaluation and analysis of why the report does not agree with Dr. Bird and the peer reviewers agreed. Dr. Budnitz reported the IPRP has also produced a report on the 2024 Updated Seismic Assessment but their report does not include a review of Dr. Bird's contentions. Ms. Seeley stated she believed Dr. Budnitz to be eager to endorse the safety of DCPP and she observed Dr. Madugo in his report discussed the possibility of the Hosgri Fault in concert with another fault producing an earthquake with a 8.0 magnitude. Dr. Budnitz confirmed this was a part of the model described by Dr. Madugo but he stated that this event has a low probability and he remarked that the event could be some distance from the plant. He commented that one should not consider magnitude as the figure of merit for an earthquake, rather it is the size of the motion at the plant or other engineered structure arising from an earthquake and the frequency of the event which are considered to be the figures of merit.

            Dr. Gene Nelson of Californians for Green Nuclear Power was recognized. Dr. Nelson referred to his letter to the NRC which he commented from earlier in this meeting wherein he claimed DCPP has favorable site conditions which attenuate or dissipate earthquake energy over relatively short distances. Due to these conditions the primary earthquake forces at DCPP would be dominated by nearby earthquake sources and by the small section of earthquake rupture closest to the plant. His correspondence cited overall plant ruggedness and seismic hazard insight as supporting safe operation of DCPP with generous safety margins during anticipated earthquakes.

            Ms. Linda Parks of Mothers for Peace was recognized. Ms. Parks inquired if there has been a peer review of Dr. Bird's work and she requested the DCISC not to defend but rather to be open minded and to consider having a peer review done of Dr. Bird's work. She remarked it is up to the DCISC to make sure of the confidence level in Dr. Bird's information, She commented she finds it unusual to have a public process where PG&E can meet with members of the Committee in private, particularly when meetings include topics specific to Mothers for Peace's expert, and she inquired whether the DCISC provided suggestions to PG&E for PG&E's presentation at this meeting. Dr, Budnitz responded and stated that with the exception of Dr. Bird's concerns on the Noto Earthquake there have been five separate individuals doing peer review of Dr. Bird's work. Dr. Budnitz remarked that a Committee member and consultant frequently meet with PG&E to discuss a myriad of issues relative to the operation of DCPP and without these opportunities to review issues the Committee could not accomplish its work. Mr. Rathie observed that individual members of the Committee have met privately with members of Mothers for Peace and have held open houses in the local community to meet with any concerned citizen but he remarked these open houses have not been well attended. He confirmed that state law prevents more than one member from meeting privately with PG&E, an interest group or a member of the public to discuss issues relative to the Committee's charge to review operational safety at DCPP.

            Mr. David Weisman of the Alliance for Nuclear Responsibility was recognized. Mr. Weisman commented a Report by the CEC prepared in 2008 in accordance with the mandate of Assembly Bill 1632 recommended that PG&E provide a report on a deterministic basis of the full effects of a San Simeon-type earthquake occurring directly below the plant particularly for non-safety-related plant components and reliability. Mr. Weisman reported the CEC AB 1632 Report has a table of source characteristics for deterministic ground motion evaluation for the Shoreline, Hosgri, San Luis Bay and Los Osos Faults, but no deterministic evaluation for a blind thrust fault such as produced the San Simeon event directly beneath the plant. He stated his question is has such a deterministic study been done and if so where can it be found? He commented PG&E received $64,000,000 of ratepayer funds to complete these AB 1632 studies and if the study he cited has not been done when might PG&E plan to fulfill the recommendation? He observed if the study has not been done it remains an open item from the 2008 CEC AB 1632 Report and he commented the CEC has just appointed the newest member of the DCISC.

            Mr. Robert Sarvey was recognized. Mr. Sarvey commented the NRC Petition Review Board has accepted the Mothers for Peace Petition to review the contentions raised by Dr. Bird, which are supported by the Independent Peer Review Panel which Dr. Budnitz just dismissed based on PG&E's position. Mr. Sarvey recommended rejecting Dr. Budnitz conclusions as Dr. Budnitz is not a seismic expert and wait for the NRC's determination on whether Dr. Bird and the Independent Peer Review Panel are correct.

            A short break followed.

            The Chair requested Consultant Mr. Wardell to continue with the report on the August 27-September 24-25, 2024, fact-finding visit which he conducted with Dr. Budnitz.

→        Meet with DCPP Officer Maureen Zawalick – Mr. Wardell reported the FFT met with PG&E Vice President for Technical and Business Services Ms. Maureen Zawalick to discuss the fact finding meeting agenda and findings and other items of mutual interest.

→        License Renewal Update – Consultant Wardell reported PG&E filed its License Renewal Application in November 2023 which he described as focused upon aging management. He reported after a sufficiency review the NRC approved the application and oral arguments were held on contentions raised and Mr. Wardell described this as an ongoing process. He reported PG&E remains in communication with NRC staff and responding to requests for additional information.

→        Unit-1 Capsule B Withdrawal – Mr. Wardell reported DCPP has made several unsuccessful attempts to remove surveillance Capsule B[13] and for refueling outage 1R25 for Unit 1 in spring 2025 the removal tool has been resized to better fit the opening on the door to the capsule compartment and during 1R25 the core barrel will be removed which will afford PG&E better access. Mr. Wardell reported a contingency plan is in place to cut out Capsule B if other removal techniques prove to be unsuccessful. In response to Dr. Meshkati's subsequent question whether cutting out Capsule B could affect its structural integrity or testing properties DCPP Director Philippe Soenen replied the contingency involves cutting out the capsule plug which is the access point for the removal tool and this would not result in any damage to surveillance Capsule B.

→        On-Line Maintenance – Consultant Wardell reported while much maintenance occurs at DCPP during refueling outages, some maintenance such as corrective maintenance needs to be dose between outages. He reported on-line maintenance is first reviewed and approved by the shift supervisor and then by the Daily Review Team. He reported if the task is urgent it is referred to a Fix It Now Team (FIN) which is a group dedicated to getting the work done in a short period of time. Mr. Wardell reported other on-line maintenance work is referred to in a twelve-week rolling matrix and then it is scheduled and a risk determination is made by the Integrated Risk Review Team as to personnel and overall risk and the work is then scheduled and completed. The FFT concluded the process was a very tight prescriptive process which gets on-line work done at the right time at the right risk.

→        Observe Licensed Operator Training: Reactor Physics – Mr. Wardell reported the FFT observed licensed operator training which he stated takes place continuously for the five operation teams for refresher and continuing training. The training observed concerned an exercise regarding reactor physics which focused upon reactivity and how neutrons behave in the reactor core. Consultant Wardell commented the instructor was qualified, the materials were good and the operators were engaged.

→        Pressurizer Safety Valve Root Cause Evaluation – Consultant Wardell reported the Pressurizer, which maintains pressure on the primary system, has several relief valves some of which are spring loaded, and open under pressure, and others are power operated relief valves. Following refueling outage 1R24 during startup, one of the safety valves was found to be leaking as the pressure was increased. Mr. Wardell reported the corrective action procedure was to drop the pressure, let the valve reseat and then increase the pressure and this was tried but it did not work in this instance. DCPP conducted an outage to replace the valve and the replacement valve was found to be leaking on restart. The reseat procedure was followed and the valve did successfully seat. A root cause evaluation was initiated to determine the cause of the leak which determined the issue was not with the valve but rather was due to a seismic support around the valve that expanded as the system heated up and this caused the seismic support to contact the valve and prevented the valve from reseating. Mr. Wardell reported the corrective action was to modify the seismic support which was successful in addressing the issue. Unit 2 was inspected as part of the extent of condition review and it was determined Unit 2 has a different design for the seismic support and did not experience leak problems. Mr. Wardell reported each corrective action which arises out of a root cause evaluation is monitored long term for effectiveness.

→        Current Campaign Moving Spent Fuel from Spent Fuel Pool to Independent Spent Fuel Storage Installation (ISFSI) – Consultant Wardell reported that to date there are currently 1,856 fuel assemblies in 58 casks at the ISFSI. He reported the eighth loading campaign began in June 2024 and it is planned to load 192 fuel assemblies in six casks for each unit, with 32 assemblies in each cask. Mr. Wardell reported this loading campaign was based somewhat on problems experienced at the San Onofre Nuclear Generating Station (SONGS) in southern California and employed more experienced workers from the Holtec firm, more robust procedures including improved training, a readiness review, and a challenge board. Mr. Wardell reported the eighth loading campaign has gone smoothly with no problems. Mr. Wardell reported the license for the ISFSI from the NRC is in the process of being renewed with DCPP's application having been submitted in 2022 and the process is ongoing at this time with the technical review expected to be completed in November 2024.

→        Results of July 31, 2024 Evaluated Emergency Preparedness Exercise -Mr. Wardell reported on July 31, 2024, with Dr. Peterson the DCISC representatives observed an emergency exercise but given time constraints the FFT was not able to review the subsequent critique of the exercise. During the September 24-25, 2024, fact finding the Emergency Response organization personnel reviewed the results of the exercise which found personnel adequately demonstrated reasonable assurance to protect the health and safety of the public and the plant employees. Mr. Wardell reported the results of the exercise included 60 out of 60 objectives met, 163 out of 164 facility objectives met, and 707 out of 724 demonstration criteria met. The FFT concluded the emergency exercise was well-designed and well-implemented.

→        Meet with NRC Senior Resident Inspector Mr. Mahdi Hayes and the new Resident Inspector Mr. Eli Garcia – the FFT met with the NRC Senior Resident Inspector to review issues and items under review by the NRC and by the DCISC.

→        Fire Protection Update – Consultant Wardell reported the Fire Protection Program was reviewed by the FFT and they met with the Program Manager and Program Engineer. He stated the Fire Protection Program has features for detection, suppression and separation of nuclear safety-related structures, systems and components. The Program was in Green[14] health status. Regarding the program cornerstones, three were in Green status and one was in Yellow status for work orders older than 100 days and for the incipient fire detection system reliability not meeting targets. Consultant Wardell reported DCPP has plans to resolve these issues and achieve Green status by February 2025. The FFT concluded the Fire Protection Program and systems were satisfactory and improving.

→        Observe Work in Progress: Calibration of Nuclear Instrumentation – Mr. Wardell stated the FFT observed work in the power block[15] which included calibration of nuclear instrumentation in the Control Room. The FFT observed the technicians using "circle and slash" place keeping techniques and numbered procedural steps along with three-way communication, use of the phonetic alphabet and independent verification, The technicians were also wearing proper protective equipment.

            Mr. Wardell requested the Members to consider approval of the August 27-September 24-25, 2024, Fact Finding Report. Dr. Peterson remarked concerning the sections of seismic response and geosciences studies and the concerns raised by Dr. Bird he is unsure if sufficient information is available to reach a definite conclusion, although he commented the recommendations are formulated such that the Committee anticipates reviewing additional information when it becomes available. Dr. Peterson stated his belief that it would be very valuable to have Dr. Bird's concerns documented in a report that could be the subject of external peer review and he commented that in the interim he does not believe there is an action the Committee needs to take specific to Dr. Bird's report. Dr. Meshkati stated he has some questions about the review of Dr. Bird's comments and concerns and he concurred in the value of having Dr. Bird's theories subjected to peer review and evaluated and validated by experts. Drs. Peterson and Meshkati stated they were prepared to consider approval of the August 27-September 24-25, 2024 Fact Finding Report without the discussion concerning Dr. Bird's concerns. Dr. Budnitz replied and he strongly expressed his view that in his discussion with PG&E experts they provided valuable additional information that substantiates the DCISC in performing its own evaluation, but he observed the DCISC has not yet found any reason to question the adequacy of the seismic safety of the plant and Dr. Budnitz emphasized that it is his belief it is important to say that. He stressed that if the Committee found something that questioned the seismic safety of the plant, there would be an obligation on the part of the Committee to make that statement and if it found nothing upon which to question the seismic safety of DCPP the Committee should say so. Dr. Budnitz reviewed the statements made in the Fact Finding Report, including that it is premature for the DCISC to reach a definitive conclusion at this time on the technical issues raised by Dr. Bird and this topic needs to await further work now underway, and he questioned how there could be disagreement on those statements. Dr. Budnitz implored his fellow members that unless they believe there are reasons to question the present seismic adequacy of the plant they should consider approving the report and he observed in his view this is the most important item on today's agenda and it is important to tell the public that at this time there are no compromises to seismic safety identified.    

            Dr. Peterson stated that he had not received a copy of the latest version of the August 27-September 24-25 Fact Finding Report and has not had the chance to review its specific conclusions. He observed the Committee should defer consideration of the report until the following day when it can be again considered and possibly be amended. In response, Dr. Budnitz then made a motion to approve the Fact Finding Report and he observed he felt strongly that his colleagues owed him the courtesy of seconding his motion and voting based on the hours he spent crafting not only the technical details but also the conclusions which Dr. Budnitz stated were purposefully ambiguous. Mr. Rathie reported Dr. Budnitz' motion lacked a second and it would be appropriate at the Chair's discretion to table the discussion until tomorrow. Dr. Peterson then called for public comment.

            Ms. Linda Seeley of Mothers for Peace was recognized. Ms. Seeley observed that when the Committee accepts a document that states the Committee has no reason to think there are any seismic issues that challenge safety at DCPP it is semantically implying that there are no issues with seismic safety at DCPP. She remarked when people read that they believe the Committee has accepted everything is fine in terms of seismic safety. She remarked as the Committee's reports go to the Governor's office the Governor's office will also look at it in the same light because people scan things and don't read them carefully,. Ms. Seeley stated it would be irresponsible for the Committee to accept. The August 27-September 24-25, 2024 Fact Finding Report.

            Dr. Gene Nelson of Californians for Green Nuclear Power was recognized. Dr. Nelson commented he believes there are sufficient caveats provided in the Fact Finding Report that it is not an absolute that the plant is perfectly safe.

            Ms. Julie Mansfield Wells was recognized. Ms. Wells respectfully submitted that Dr. Budnitz' opinion the DCPP is seismically safe should not be attributed to the entire Committee as it has not accepted the Fact Finding Report and she agreed it should be tabled until tomorrow She stated it appears Dr. Budnitz' analysis of Dr. Bird's report is a presentation of PG&E position that the plant is safe and she stated there is adequate reason to question seismic safety as reported by the IPRP and Dr. Bird. She stated she was offended by what she described as Dr. Budnitz bullying of the Committee into accepting the report. She respectfully requested that the DCISC not accept the report until more information is obtained.

            Mr. Daniel Hirsch was recognized. Mr. Hirsch stated he is the retired director of the Program on Environmental and Nuclear Policy at the University of California at Santa Cruz. Mr. Hirsch stated he was deeply shocked by what occurred regarding the issues raised by Dr. Bird. He commented he has not seen an academic process where the investigation is to go to the entity that poses the potential risk, in this case PG&E, and ask them if they agree there is a lack of safety. Mr. Hirsch stated he wanted to plead with Dr. Meshkati to be a restraining force and he observed the issues raised by Dr. Bird were serious. Mr. Hirsch commented concerning Dr. Budnitz assertion concerning margin to deal with earthquakes that the plant was built on the assumption there were no earthquakes within 20 kilometers and the Hosgri Fault was subsequently discovered. He commented PG&E insisted on an amendment from the safety requirements posed by the Hosgri Fault with the statement that there would not be other faults found. Then the Los Osos and subsequently the Shoreline Faults were found. Mr. Hirsch stated therefore the plant was not designed to withstand all of the earthquakes that we now know can occur but was instead designed to withstand none of them. He remarked one should not make a statement that there is no reason to question the adequacy of seismic safety as Dr. Budnitz proposes when one is planning to question the adequacy and conduct further review. He pled with Dr. Meshkati as this is Dr. Meshkati's first meeting to be a restraining force and to push for true science and not to be deeply tied to the operator of the plant that has an economic incentive in sweeping things under the rug.

            Ms. Rochelle Becker of the Alliance for Nuclear Responsibility was recognized. Ms. Becker stated the Alliance has sought to have term limits for the DCISC and the Public Utilities Commission is considering the matter. She stated she was shocked by Dr. Budnitz statement that he was owed a vote on the report.

            Dr. Peterson stated the Committee would return to this topic tomorrow for further discussion and he stated his recommendation would be to modify the conclusions to include a recommendation that a report should be generated and subjected to peer review on the issues raised by Dr. Bird.

B.        The Chair requested Consultant Wardell to provide a summary report on the July 31-August 1, 2024, fact-finding visit with Dr. Peterson. Mr. Wardell reviewed the topics discussed with PG&E during that visit as follows.

→        Observation of the July 31, 2024 NRC Evaluated Emergency Exercise – Mr. Wardell stated the FFT observed the all-day NRC evaluated emergency exercise which was based on a postulated scenario involving a trip on 100% power by Unit 1 due to loss of the 12kV electrical bus, with a small break loss of coolant accident (LOCA) on Unit 2 at which point the Emergency Response Organization was activated as was the County of San Luis Obispo and other agencies. A Containment penetration failure then occurred with radioactive materials in Containment due to the LOCA which allowed radiation to leak to the environment from Containment. The Emergency Response Organization (ERO) then made protective action recommendations to the County for the County to make a decision. The Joint Information Center held a mock news conference and issued press releases as did the County and local municipalities. Mr. Wardell described this as a fairly typical scenario for an emergency exercise. He reported the DCISC representatives began their observation in the Simulator, a full-scale mock-up of the Unit 1 Control Room, and witnessed the operators execute the correct responses to the scenario, then the team moved to the Emergency Operations Facility, which is staffed by DCPP and the County including the County Sheriff's office, and then visited the Joint Information Center where PG&E and the County provided news releases and answered question from the mock media representatives. Mr. Wardell reminded those present he presented the results of the exercise critique during his earlier fact finding report and stated the FFT concluded PG&E did a good job designing the exercise and implementing the emergency plan.

→        DCPP Stranded Plant Procedure and FLEX – Consultant Wardell reported the FFT discussed post-earthquake inspection procedures with DCPP which include determining what equipment and personnel are available and what actions need to be taken after an earthquake. The FFT recommended the plant review the stranded plant procedures and add a review of FLEX[16] equipment availability. Mr. Wardell reported the Stranded Plant procedure was changed in response similar to the change to the post-earthquake procedures. Dr. Peterson commented this issue relates directly to the seismic safety of the plant. He commented DCPP was specifically engineered for high seismic conditions relative to other nuclear power plants and he gave the example of the Containment having a gantry crane instead of a polar crane in the effort to reduce mass and allow Containment to survive substantially higher accelerations. He reported the key thing is the residual risk associated with seismic events is mitigated by the fact that the plant staff have the capability to take actions afterwards and the DCISC's primary concern is make sure everything is prepared so that FLEX equipment is available. He reported the updates to the procedure guidelines provide transition points to restore basic safety functions if necessary. He observed the availability of FLEX type equipment would have dramatically changed the outcome of the accident at the Fukushima Daiichi plant in Japan.

→        Annual Radiological Reports – Consultant Wardell reported the DCISC annually reviews the Radioactive Effluent Release Report and the Radiological Environmental Monitoring Report which respectively monitor radioactive materials released to the environment and the effects of plant activity on the surrounding environment. Both reports are regularly submitted to the NRC. He reviewed the results of the release of liquid gaseous and solid waste which he described as extremely small and very low percentages of permitted amounts. He remarked solid waste is not released to the environment but is shipped offsite to a licensed facility. Mr. Wardell reported direct radiation is not a release to the environment of a radioactive material and is typically gamma rays which might be released from spent fuel at the ISFSI and he reported nothing released from the plant has been determined to reach the site boundary where radioactivity remains at background levels. He reviewed the number of samples taken and evaluated from water, soil, vegetation, air, and from thermoluminescent dosimeters used to measure radiation levels and reported there were some 1,800 analyses performed from substances such as meat, milk, vegetation, drinking water, ground water, well and surface water, aquatic species and ocean sediment. He reported the FFT found there are no unusual environmental isotopic findings from plant operation, there are no unusual trends compared to pre-operational data obtained before the plant began operation, and there are no detectable off-site radiological impacts.

→        Operational Experience Program Update – Consultant Wardell reported this is a program where each nuclear plant shares with the industry and other plants events which occurred at the reporting plant and what actions were taken in response. The input typically comes from the Institute of Nuclear Power Operations (INPO) but may also come from the NRC and equipment vendors. Mr. Wardell stated an Operational Experience Program coordinator at DCPP assesses and logs the input and models or reviews the input with a subject matter expert and implements corrective action tracking in the Corrective Action Program. Each time an item is received it is reviewed and a determination made as to whether it is applicable to DCPP. Mr. Wardell described the Operational Experience Program as very effective and a part of the Performance Improvement Program at the station. He remarked the applicable items typically result in some improvement either in procedures, modifications to equipment or systems or in other areas. In 2024 to date there were 224 reports received with 144 deemed applicable to DCPP, of which 5 resulted in additional actions.

→        Workplace Seismic Safety – Consultant Wardell reported this program at both the corporate and plant level seeks to protect people by bracing office furniture. He reported in the past few years the DCISC has found DCPP to be in compliance but during this visit a cabinet was found in a conference room that was unsecured. The Maintenance Director who happened to be present initiated a notification in the Corrective Action Program. Mr. Wardell stated the FFT issued a concern on this issue.

→        Nuclear Liability Insurance – Mr. Wardell stated the FFT followed up on this topic from a previous visit and reported the federal Price Anderson Act[17] provides up to $10 billion in coverage to the public no matter who is at fault for damage caused by a nuclear power plant accident. Each plant also carries additional private insurance and Mr. Wardell reported DCPP is in compliance. Each plant files a report with the NRC every year and the FFT determined DCPP was appropriately maintaining the required insurance.

→        Meet with DCPP Officer – the FFT met with PG&E Site Vice President Mr. Adam Peck to discuss the fact finding team's agenda and other items of mutual interest.

→        Meet with NRC Senior Resident Inspector – Mr. Wardell reported the FFT met with the NRC Senior Resident Inspector Mr. Mahdi Hayes and he reported a second Resident Inspector, Mr. Eli Garcia, has recently been assigned to DCPP.

→        Spent Fuel Movement to ISFSI – Consultant Wardell reported the FFT followed up on the spent fuel transfer as he reported earlier during this meeting and he reported the transfer of spent fuel is moving along smoothly.

            Ms. Sherry Lewis of Mothers for Peace was recognized. In response to Ms. Lewis question as to how the levels of radioactivity were measured as described in Mr. Wardell's report on environmental monitoring, Dr. Peterson replied as the doses were not detectable above background levels they are too small to actually measure and accordingly they are calculated.

            Ms. Linda Seeley of Mothers for Peace was recognized. Ms. Seeley offered a correction to Mr. Wardell's report and stated the Price Anderson Act now increased liability coverage to $16 billion and she observed cumulative property value in San Luis Obispo County as of 2023 was $78 billion.

            On a motion made by Dr Budnitz, seconded by Dr. Meshkati, the July 31-August 1, 2024 Fact Finding Report was unanimously approved and its transmittal to PG&E authorized.

C.        The Chair requested Consultant McWhorter to provide a summary report on the August 21-22, 2024, fact-finding visit with Dr. Meshkati. Mr. McWhorter reviewed the topics discussed with PG&E during that visit as follows.

→        Plant Design and Major System Functions – Consultant McWhorter reported as this was Dr. Meshkati's first visit to the site an effective briefing on plant design and major systems was provided by DCPP Senior Director of Engineering Mr. Alan Wilson.

→        Site Area Tour – the FFT toured the site including visiting the Intake Cove where information and a waterborne tour was provided and information was given on the design of the Intake Cove and the marine life in the area including the impact of the Intake Facility and of the recent dredging activities on marine life. The FFT also toured the DCPP Fire Department, the ISFSI, the old steam generator storage facility, the switchyards, and the Control Room Simulator.

→        Probabilistic Risk Assessment (PRA) Program – Mr. McWhorter reported the DCISC representatives received an update on the PRA Program including the history of PRA at DCPP and in the industry and current PRA Program activities which he reported consist mostly of risk informed program changes being considered in context of License Amendment Requests (LARs). Mr. McWhorter reported some LARs have been submitted and more are pending with five LARs being done as part of a move to more risk-informed regulatory compliance. The FFT discussed the effects of the license extension on the PRA group which he stated now supports PG&E's corporate non-nuclear organization endeavors as well as DCPP.

→        Station Organization and Major Programs – Consultant McWhorter reported the FFT received information on issues of PG&E corporate safety and governance and the effect on nuclear safety culture at DCPP. The DCISC representatives discussed information concerning the lessons learned from the San Bruno, California, gas explosion and the Camp Fire wildfire events. Consultant McWhorter stated Dr. Meshkati may have additional more questions on these topics which will be further explored during a fact finding in January 2025. Mr. McWhorter commented the Committee often receives comments from members of the public on aspects of corporate safety and culture and any resulting effect on the plant and he remarked PG&E has had a very high visibility concerning its safety struggles in the last ten years. Dr. Meshkati stated this is a very important issue and unfortunately corporate culture and safety was a major issue for the Boeing firm. He remarked on the relationship between the PG&E Board of Directors over the operation of DCPP in terms of safety and quality and he stated he hopes to learn more about the functioning, responsibility, role, accountability and oversight provided by the PG&E Board of Directors Safety and Nuclear Oversight (SNO) Committee. 

→        Meeting with NRC Senior Resident Inspector – the FFT met with Mr. Mahdi Hayes. the NRC Senior Resident Inspector, as well as a Specialty Inspector from NRC Headquarters to discuss items of mutual interest. Mr. McWhorter commented the Senior Resident Inspector would be making a presentation to the DCISC later during this public meeting.

→        Corrective Action Program and Human Performance – Consultant McWhorter reported this was an orientation for Dr. Meshkati as well as to receive an update on human performance at the station. Information was provided on how issues are identified, documented and reviewed by various teams at the station and for equipment deficiencies how work is scheduled to repair and correct those issues. He commented Dr. Meshkati had questions concerning how the Human Factors Analysis and Classification (HFAC) approach is used to review events at the station and to capture lessons learned. Mr. McWhorter reported the FFT has a follow up scheduled to review what types of things after a human performance event occurs trigger doing an analysis under HFAC principles. He reported the FFT found the Corrective Action Program was performing well and human performance tools were being adequately used.

→        Lunch with Senior Leadership Team – Consultant McWhorter reported the FFT met with Site Vice President and Acting Chief Nuclear Officer Mr. Adam Peck, Senior Director Mr. Tom Jones, Director Mr. Justin Rogers and other DCPP senior leadership personnel during a working lunch.

→        License Renewal Application – the FFT received an update on the License Renewal Application and the results of the most recent NRC inspections performed during the last refueling outage around those activities with regards to aging management inspections and Mr. McWhorter reported the results have been generally excellent. He reported Dr. Meshkati posed some specific questions concerning reactor pressure vessel embrittlement which is part of the analysis required by the License Renewal Application. Dr. Meshkati's questions included how uncertainties are handled and concerning reactor vessel performance monitoring. These questions stemmed from Dr. Meshkati's review of a 2022 NRC document that was recently quoted by Mr. Bruce Severance during Mr. Severance's remarks to the Committee at previous public meetings. Mr. McWhorter stated PG&E provided some answers and further discussion on related topics may be part of the presentation to be made during the evening session at this public meeting.

→        Plant Tour – the FFT toured within the protected area including areas within the Turbine Building, the emergency diesel generator areas, the Control Room, spent fuel pools and the cask handling areas. Consultant McWhorter reported the FFT observed a loaded spent fuel storage cask which had been removed from the spent pool fuel having its lid welded and being prepared for transfer to the ISFSI using a HI-TRAC transfer cask. Mr. McWhorter reported the areas of the plant toured by the FFT appeared in good working condition and plant cleanliness was generally good.

            Dr. Meshkati expressed his thanks to PG&E and to Ms. Brandy Lopez for her assistance in organizing this fact finding visit and in subsequently providing material related to the visit and to Senior Director Mr. Tom Jones, as well as to other members of DCPP leadership. He commented the visit was characterized by openness in response to the FFT's questions, transparency, and collegiality.

            On a motion made by Dr. Peterson, seconded by Dr. Meshkati the August 21-22, 2024 Fact Finding Report was approved and its transmittal to PG&E authorized.

XI        ADJOURN AFTERNOON MEETING

            The Chair adjourned the afternoon session of the DCISC at 5:00 p.m.

XII      RECONVENE FOR EVENING MEETING

            Dr. Peterson convened the evening session at 5:05 p.m. and stated this evening the Committee will receive an informational presentation on evaluations of public input on studies by Dr. Mark T. Kirk, evaluating Unit 1 reactor pressure vessel integrity. Dr. Peterson then asked Dr. Kadak to introduce Dr. Kirk. Assistant Legal Counsel Rathie announced the Committee has determined a four minute time limit will apply to public comments, which will follow Dr. Kirk's presentation and the Committee's questions. He reported Mr. Bruce Severance previously asked for extra time to address remarks to the Committee and Mr. Severance will be granted six minutes for that purpose.

XIII     COMMITTEE MEMBER COMMENTS

            There were no comments by Committee Members at this time.

XIV     INFORMATION ITEMS PRESENTED BY THE COMMITTEE

A.        Report on Evaluations of Public Input on Studies by Dr, Mark T, Kirk Evaluating Unit 1 Reactor Pressure Vessel Integrity; Committee Consideration of the Kirk Studies and Including Conclusions and Recommendations in the DCISC's 34th Annual Report.

            Dr. Kadak stated Dr. Kirk was retained by the Committee to do an independent investigation of the status of embrittlement of the Unit 1 reactor pressure vessel (RPV). The Committee's investigation of this topic has been ongoing for almost two years and has resulted in many comments and interactions with the public. Dr. Kadak reported Dr. Kirk would be participating remotely from Japan via Zoom.

            Dr. Kirk stated he would be reporting on an evaluation of public input concerning the embrittlement status of Unit 1. The presentation will cover background, initial public concerns the lead up to the issuance of the two reports written for DCISC and on which Dr. Kirk reported at the February 2024 DCISC public meeting. He reported additional technical evaluations on three different topics have been prepared and summary conclusions that have been proposed for inclusion in the 34th DCISC Annual Report.

            Dr. Kirk reported that prior to his involvement in the matter, at the request of the California Energy Commission the DCISC reviewed the status of reactor vessel integrity for a twenty-year license extension with reference to the phenomenon of pressurized thermal shock (PTS)[18]. In February of 2011 the DCISC evaluated PTS and seismic effects and concluded that, subject to the availability of any new information, at that time both units could safely operate for twenty additional years relative to any concerns about PTS. In 2022 it was announced that DCPP would be not shutting down after forty years of operation, but instead would be seeking a license extension from the NRC. Significant public interest then arose concerning the plant in general and RPV embrittlement in particular and in public meetings held in February, June and September of 2023 the public expressed its concerns about the Unit 1 embrittlement status. These parties in particular have included Mr. Bruce Severance, and the San Luis Obispo Mothers for Peace, and Mothers for Peace have retained Dr. Digby Macdonald as a subject matter expert.

            In October 2023 Dr. Kirk reported the DCISC retained him to help address these concerns, and in late January of 2024 the DCISC issued a report by Dr. Kirk in two parts on its website. He stated these reports and all subsequent communications between himself and the DCISC and the public are available on the DCISC website for public review. Dr. Kirk stated in February 2024 he attended a public meetings and presented Part One and Part Two of his Report to the Committee and to the public. Since that time there have been several additional iterations with public concerns. At the end of February 2024 the DCISC requested additional comments be provided by mid-March 2024, but that was later extended to mid-April. There were several exchanges with both Mr. Severance and Dr. Macdonald, representing the San Luis Obispo Mothers for Peace, and all the questions and replies and the documentation are available for review on the DCISC website at www.dcisc.org.

            Dr. Kirk reviewed the conclusions of his two-part Report on Unit 1 embrittlement which confirmed and validated PG&E's embrittlement calculations, Dr. Kirk was able to determine that Unit 1, which is the unit of concern, meets the NRC's requirements for reactor vessel integrity through an expected sixty years of service. He remarked the credibility of the data (and Dr. Kirk observed credibility is a term that is defined by the NRC to mean that the embrittlement data that is collected through the surveillance program is in good agreement with the embrittlement trend model) was correctly assessed which he stated contributes to the confidence in the calculations having been properly done. DCPP has also made use, as it is required to do by the NRC, of sister plant data. Sister plant data is data from a similar weld metal that has been irradiated in the surveillance program, but was exposed to irradiation at another plant. Dr. Kirk reported PG&E did that calculation correctly and in accordance with NRC requirements.

            Dr. Kirk recognized, as many people are aware, surveillance Capsule B[19], the next surveillance capsule to be withdrawn, was initially scheduled for withdrawal in the mid-2000s but there have been several delays since then. The current schedule is for Capsule B to be withdrawn during 2025 in the 1R25 refueling outage. Dr. Kirk reported the several delays were appropriate and consistent with standard industry practice and additionally the ultrasonic inspection schedule for the vessel is appropriate. Removal of Capsule B is needed by 2028 to be consistent with NRC guidance, but Dr. Kirk stated PG&E has expressed a strong commitment to remove it in 2025 when the reactor core barrel will also be removed which should make it easier to reach the surveillance capsule. Dr. Kirk stated when new data from the removed Capsule B are obtained, or when any new data are obtained, it may change the outcome of the current pressure vessel integrity assessment and one cannot guess at what those results may be.

            Dr. Kirk reported the DCISC asked him not to just simply follow the NRC legal requirements, but also to apply current best practices such are being developed and discussed by the American Society of Mechanical Engineers (ASME) to take a second look at the data. He stated he did that and concluded it is very unlikely that Unit 1 will exceed the PTS screening criteria before sixty years of operation. If modern data analysis is used, as is now being considered for codification by ASME, it can be determined that Unit 1 is forecast to have a longer acceptable lifetime than the current NRC approach.

            Dr. Kirk stated in Part One and Part Two of his Report he also did a supplemental analysis for upper shelf energy[20]. Based on that analysis he concluded that the upper shelf energy may fall below the NRC screening criteria in approximately five years, that is, by 2029 or 2030. However, Dr. Kirk observed in all cases in the United States where a nuclear plant has been forecast to fall below the 68 joules upper shelf energy screening criteria, those plants have then been able to do a more accurate analysis using elastic plastic fracture mechanics to follow the NRC guidance. In all cases these other plants have been able to show that they retain acceptable margin until well below an upper shelf energy of 68 Joules. Dr. Kirk stated that type analysis has not been done for DCPP but Dr. Kirk stated he would be surprised if Unit 1 could not continue to show upper shelf integrity well past 2029.

            Dr. Kirk then turned to the additional exchanges with both Mr. Severance and Dr. Macdonald, since his presentations and reporting at the February 2024 public meeting, all the details of which are on the DCISC website. He reviewed comments by Mr. Severance in April 2024, and the response that was later posted. Mr. Severance again asked whether the NRC procedures were used correctly, in particular the NRC credibility assessment for the use the sister plant data and the existence, in Mr. Severance's opinion, of limited data. Mr. Severance also asked why embrittlement forecasts have changed over time. Dr. Kirk stated, especially for a non-specialist, the procedures for reactor vessel integrity are not completely intuitive, so he has tried his best to explain to Mr. Severance. Dr. Kirk observed he believes Mr. Severance's comments reflect a misunderstanding of NRC procedures. In terms of why the embrittlement forecast changed over time Dr. Kirk reported this is simply a consequence and a natural outcome of the surveillance program which is designed at the beginning of the plant's life to provide a periodic check on the embrittlement level of the vessel. Every time a surveillance capsule is withdrawn new data are obtained and one then adjusts the embrittlement prediction based upon the new data. Therefore, the forecast of embrittlement can improve over time as one gets more data and that is why the embrittlement forecasts have changed over time from start-up of Unit 1 until today.

            Dr, Kirk addressed a second question having to do with deferral of the removal of surveillance Capsule B and its impact and Mr. Severance's claim that the NRC had required a fourth capsule for the original forty year license term. Dr. Kirk stated he reviewed the NRC requirements and DCPP Unit 1 licensee requirements and he again confirmed that Unit 1 is licensed to the 1970 version of ASTM E 185. In 1970 all plants were required to have three capsules during the first forty years of operation and therefore DCPP is a three capsule plant. While the NRC document that Mr. Severance referred Dr. Kirk to from 2006 does discuss a fourth capsule Dr. Kirk stated that it does not amend Diablo Canyon's forty year license to make that fourth capsule mandatory. Dr. Kirk reported that the three surveillance tests that have been done cover the amount of fluence, that is, the amount of neutron exposure that Unit 1 has experienced up until today. Even though the last capsule was removed from Unit 1 some time ago it is representative of the neutron exposure conditions experienced by the Unit 1 RPV today.

            Dr. Kirk reported Mr. Severance reminded him that the supplemental analysis of Upper Shelf Energy shows Unit 1 may reach the screening limit by 2029 or 2030, however, Dir Kirk reported the analysis was not required by the NRC, so the NRC would need to decide to take action on the basis of that analysis or something else submitted by the public should they deem it necessary and to date the NRC has not done so. Dr. Kirk again observed many plants have reached a similar conclusion, i.e., that their Upper Shelf Energy falls below the NRC 68 joules screening criteria and in every case those plants were able to show acceptable continued operating integrity to Upper Shelf Energy values much below the 68 Joules screening criteria.

            Dr. Kirk stated the impact of these discussion is that none of Mr. Severance's concerns change the conclusions of Part One or Part Two of his Report. The embrittlement predictions continue to comply with NRC regulation, PTS screening criteria will not be exceeded during sixty years of operation. USE requirements are currently satisfied, Capsule B was never required to be withdrawn during the first forty years of Unit 1's operation, and PG&E's plan to test Capsule B earlier was at its decision and not pursuant to a requirement of the NRC. Finally, even if NRC's PTS or USE screening criteria are surpassed before 60-years of operation Diablo Canyon will, like all other licensees, have other options by which continued compliance and operating safely can be demonstrated.

            Dr. Kirk reported Mr. Severance made some additional comments in July 2024 to which a reply was made in August. In his comments Mr. Severance challenged the NRC's process of reviewing embrittlement, in many cases referencing Dr. Macdonald's independent correspondence with the Committee. Dr. Kirk observed that Mr. Severance continues to challenge the appropriateness of the use of sister plant data, challenges Dr. Kirk's embrittlement assessment, since it's not NRC approved which Dr. Kirk remarked he has stated that this assessment was not intended to be NRC approved rather it was intended to be current data practice, and Mr. Severance again challenges the claim that Unit 1 is a three capsule plant. Dr. Kirk reported he has addressed most of these comments previously. He observed that as Mr. Severance challenges the NRC's process this is not something that can be addressed either by Dr. Kirk or the Committee, but if Mr. Severance or anyone has concerns that the NRC's process is not appropriate or is not adequately conservative, a 10 CFR 2.206 petition can be filed with the NRC and the NRC is obligated to review and assess the concern raised.

            With reference to Dr. Macdonald's concerns, which began with Dr. Macdonald's presentation to the DCISC during the June 2024 public meeting. Dr. Kirk displayed a listing of Dr. Macdonald's concerns along with Dr. Kirk's responses. Dr. Macdonald stated that Unit 1 is dangerously embrittled and should be shut down. Dr. Kirk observed that while Unit 1 is embrittled he would not use the term dangerously. Unit 1 is embrittled and Unit 1 meets the NRC safety screening criteria through sixty years of operation. Dr. Macdonald stated that Unit 1 has unjustified reliance on integrated surveillance data and he claims that Dr. Kirk's analysis is not credible, meaning appropriately not credible by NRC definition when both DCPP and data from the Palisades Nuclear Generating Station in Michigan (Palisades) are used. Dr. Kirk remarked that Unit 1 does not employ an integrated surveillance program, that is, a separate process for which PG&E would have had to have an approved integrated surveillance program in place in lieu of their plant specific surveillance program and they do not have that. Unit 1 appropriately uses data from similar material from other plants, in this case Palisades, as has been required by the NRC and has become standard practice for all nuclear utilities in the United States. Dr. Kirk remarked that the Palisades and DCPP data which he will show in a graph consistently follow the forecast embrittlement trend in accord with the NRC's Regulator Guide[21] (Reg. Guide) 1.99 Revision 2, which takes from dates from the 1980s, but also with more recent embrittlement trend curves. Dr. Kirk observed there is very good agreement between the plant specific surveillance data and the general trends that are expected, as expressed both by the regulatory equation and by current state of the art equation.

            Dr. Kirk reported Dr. Macdonald proposes his own unique extent of embrittlement (EOE) approach instead of the NRC process. Dr. Macdonald admits that EOE has not been published or peer reviewed, however, when Kirk used the EOE approach he stated he found out that EOE produces results comparable to the NRC approach, but in fact it is a little bit less conservative. So, Dr. Kirk stated if one were to use Dr. Macdonald's EOE approach to forecast the remaining licensable lifetime of Unit 1, one would get a longer lifetime than from using of the NRC's required approach. Dr Macdonald also provided a forecast of RT_NDT with increasing fluence. Dr. Kirk remarked this included one datum that was not used by either Dr. Kirk or PG&E and Dr. Macdonald stated that the use of that datum would reduce the period of PTS acceptability. Dr. Kirk used a graph whose function he explained and showed that Dr. Macdonald found this datapoint at adjusted reference temperature = 161° F and he referred the Committee to a NRC report where Dr. Macdonald got that value. Dr. Kirk observed that this report was the technical basis evaluation for the change from Reg. Guide 1.99 Rev.1 to Reg. Guide 1.99 Rev.2, published in the late 1980s. He remarked that datum, adjusted reference temperature =161° F is not surveillance data akin to other data. It is simply the prediction of a model and so it should not be included in surveillance data analysis. Dr. Kirk remarked Dr. Macdonald was completely correct that if that measurement was valid, that would change the predictions and therefore would change where the regulatory assessment lines, which were shown by curves on a graph displayed by Dr. Kirk, cross the PTS screening criteria. So, Dr. Kirk stated if one did indeed have a high measured value it would change the embrittlement prediction considerably, but Dr. Kirk stated it is not a measured value but rather a prediction and so it does not belong in the analysis. In response to Dr. Peterson's inquiry concerning the basis for the use of uncertainty bounds Dr. Kirk replied Dr. Macdonald was correct to point out that every experimental measurement has uncertainty and the horizontal uncertainty Dr. Macdonald illustrated was plus or minus twenty percent on fluence, which is the NRC value, and the vertical uncertainties that Dr. Macdonald showed were plus or minus one standard deviation on the embrittlement shift value, Dr. Kirk stated that on his original graph he acknowledged that there is uncertainty but he did not include uncertainty bands, the NRC procedures for assessing the allowable remaining lifetime without doing further analysis account for the uncertainty in the measured data.

            Dr. Budnitz stated he wonders how the fluence, which he termed the neutron integrated dose, could be as uncertain by as much as plus or minus twenty percent. Dr. Kirk replied dosimetry is definitely not within his expertise, but what he has learned from others who practice in this field is that the ±20% value is an upper bound dating from regulatory guidance that is now twenty years old and that much better accuracy is now available. Dr. Budnitz stated his recollection was the NRC's regulatory guidance states if one does not know the uncertainty very well using twenty percent, plus or minus is acceptable, but if one can defend a tighter uncertainty that is also acceptable. Dr. Kirk stated he believed Dr. Budnitz was correct.

            Dr. Kirk stated Dr. Macdonald claimed that Unit 1 has had no reliable reference temperature data since 2003 and therefore that Unit 1 needs more testing of capsules and Dr. Macdonald claims the NRC surveillance requirements make DCPP a five capsule plant. Dr. Kirk confirmed that DCPP withdrew its latest surveillance capsule 2003, however, because of the lead factor what that means is that in 2003 PG&E had an embrittlement measurement at a fluence exceeding that which would be experienced by Unit 1 after more than forty years of operation. While the last data was collected in 2003, it gave PG&E a look twenty-plus years into the future. Dr. Kirk remarked consideration of the Palisades data provides data to even higher fluences because of the lead factor inherent to those surveillance capsules. Thus, the Palisades data provides a measured data point in excess of where DCPP will be after sixty years, if the plant should run for sixty years. Dr. Kirk remarked there may have been some misunderstanding about the requirements for surveillance but DCPP Unit 1 was not a five capsule plant. In its initial forty year license it was as a three capsule plant. PG&E has now applied to the NRC for a twenty year license extension and one needs to wait and see what the NRC says, but in Dr. Kirk's opinion the NRC will probably require one more capsule to be withdrawn and tested during the twenty year license extension and that capsule will probably be Capsule B next year.

            Dr. Kirk displayed another graph and remarked both Mr. Severance and Dr. Macdonald have suggested that additional capsule testing is urgently needed due to lack of information. Dr. Kirk stated his opinion that additional testing on an urgent basis is not needed for the following reasons. Since 2011, which is when the data from Palisades was incorporated by a Westinghouse report into the pressure temperature limits assessments for DCPP Unit 1, data has been available for fluence above that of the Unit 1 pressure vessel experience after sixty years of operation so there is direct evidence regarding the limiting weld of what's going to happen twenty years from now. Those data are well predicted by the existing embrittlement models, both the NRC's model which dates from the 1980s, and also a much more recent assessment of embrittlement trends by ASTM. The data has not shown evidence of unexpected behavior that in Dr. Kirk's opinion would warrant additional attention and there will be additional data from Capsule B which will be withdrawn in 2025, tested after that, and reported to the NRC and to the public by 2027. Dr. Kirk observed that will provide another data point that will influence the overall assessment.

            Dr. Kirk commented Dr. Macdonald observed that Unit 1 has performed no ultrasonic testing (UT) since 2005 and Dr. Kirk reported that in 2014 PG&E performed a partial UT of Unit 1. He reported there were some technical difficulties in getting that testing done, therefore PG&E applied for a UT interval extension from ten to twenty years and Dr. Kirk remarked this is not unique to Unit 1, as many plants have had similar extensions approved by the NRC. Dr. Kirk reported PG&E plans for UT testing to happen during the next refueling outage and that is why the reactor core barrel is being removed during 1R25 to provide the inspectors with access to the inner diameter of the vessel. Dr. Kirk pointed out that there is no evidence of flaw growth in pressurized water reactors (PWR) vessels during service and this is why the NRC is granting UT interval extensions. He commented the ten year interval was established in the 1970s for reasons that it seemed valid at that time and he commented he has been unable to find documentation of why ten years was picked. Nevertheless, subsequent service experience has shown that vessels performing 10, 20 and 30 year inspections are basically re-examining a static condition. The initial weld defects are not growing, and this is the technical reason why the NRC has been comfortable granting these extensions.

            In response to Dr. Budnitz' query Dr. Kirk replied that until approximately 2010 every operating nuclear power plant was obligated to do a one hundred percent UT inspection of all the welds in the vessel beltline. So every weld, including the region six inches from the weld center line, has been inspected. All of that information is available and over thirty years, three hundred inspections or so were performed fleet wide. This information shows no evidence of flaw growth over that time. Dr. Budnitz stated he heard that UT was not a very effective way to look for these types of things over long periods of time because UT does not have sufficient resolution power. Dr. Kirk replied and stated he is not an expert in UT but he can say that the resolution of UT has been continuing to increase over time, such that the UT inspection performed at thirty years is better than UT inspections performed at twenty years and better than those performed at ten years. So in Dr. Kirk's opinion UT can reliably find flaws of engineering size.

            Dr. Meshkati asked Dr. Kirk concerning the role of UT in performance monitoring and commented he remembers from Dr. Kirk's reports that Dr. Kirk said UT inspection was effective for identifying flaws in and near the structural weld seams, but not useful for embrittlement monitoring. Dr. Kirk replied that Dr. Meshkati was correct, he stated UT inspection can find initial fabrication defects and it can find if those initial fabrication defects are extending. However, radiation embrittlement involves movement of individual atoms out of place, or causing dislocation pile-ups on impediments to dislocation motion like around a copper precipitate and causes damage at the atomic scale. UT can't find atomic scale defects and wasn't designed to do so. Dr. Kirk stated in his Report he identified both UT and surveillance testing as part of a reactor pressure vessel integrity performance monitoring programs, but they do not monitor the same things. UT is looking for millimeter and greater sized flaws and to see if they are getting larger due to a fatigue or stress corrosion cracking mechanism. The mechanical property tests that are performed from the surveillance capsules provide monitoring of embrittlement.

            Consultant McWhorter observed and Dr. Kirk agreed that while UT inspection is not a direct measure of embrittlement it is related to pressurized thermal shock in that UT testing would detect flaws that exist and could become a source of initiation or a crack developing and that is a very important contributor to pressurized thermal shock in that you have to have that before that crack will propagate. Dr. Kirk stated in order to have a flaw driving force, one needs a crack to commence. He commented with the standard NRC pressurized thermal shock rule, 10 CFR 50.61, the NRC's viewpoint has been that the size of the flaws that were postulated in setting the embrittlement screening limits were so conservative, were so very much larger than anything that's ever been found in service, that there was no need to check any assumptions concerning crack size. Dr. Kirk further stated that it is 10 CFR 50.61 screening criteria with which Unit 1 continues to comply. Dr. Kirk observed if DCPP Unit 1 or any other PWR elects to use the alternative PTS rule 10 CFR 50.61a, then the licensee would be obligated to use ultrasonic inspection to characterize the size and number of flaws in the reactor vessel beltline and then compare that to the size and number of flaws to the values that the NRC used in its calculation to establish the alternative screening criteria in 10 CFR 50.61a.

            Dr. Kirk reported Dr. Macdonald has stated that hydrogen induced cracking may affect Unit 1. Dr. Kirk observed that to date there has been no evidence of hydrogen induced cracking in any U.S. or other PWR reactor anywhere in the world. Also, primary circuit chemistry, water chemistry, is controlled with the express purpose of preventing the condition for hydrogen induced cracking to begin.

            In concluding his remarks concerning Dr. Macdonald's work Dr. Kirk reported Dr. Macdonald has suggested that information from ex-Soviet designed reactor steels could provide useful information for Unit 1. However, Dr. Kirk stated those steels are considerably different in their composition and in their embrittlement behavior, and so in Dr. Kirk's opinion the ex-Soviet data provides no useful information with respect to Unit 1. He reported the international radiation damage community has been working for some time to reconcile the Soviet embrittlement trend data and the western design reactor embrittlement trend data and he reported the underlying physical mechanisms differ, so it is not useful to combine those two datasets or try to infer from one set of data what's going to happen with the other.

            Dr. Kirk stated he would move on in his presentation to address three additional evaluations he performed, together with Dr. Kadak, on three topics. An evaluation was performed of the potential impact of Capsule B results which he described as a sensitivity study, a reevaluation of the Upper Shelf Energy evaluation from Part Two of his Report, and an assessment of the impact of some recent NRC plans for rulemaking.

            Concerning the Capsule B analysis the objective was to postulate what that the results from capsule testing might be and seeing what effect these new data would have on the projected remaining lifetime of Unit 1. Dr. Kirk stated the Capsule B results may place Unit 1 into one of two categories. If the data set that includes Capsule B results is credible per the NRC definition then the vessel will be forecast to have a life that's acceptable for PTS until far beyond sixty years. However, if the data set that includes Capsule B results is not credible per the NRC's definition, then the vessel will be forecast to be acceptable for PTS until approximately fifty years. Dr. Kirk stated in the latter situation, it's up to PG&E to decide what to do next, which might include offering the NRC additional justification as to why they should be allowed to operate longer, for example, by using the alternate PTS rule and incorporating inspection evidence. Alternatively, PG&E could perform additional fracture toughness measurements or a number of other things to justify continued operation. Dr. Kirk observed regardless of the outcome of the Capsule B testing PG&E has time to consider what to do next. Dr. Kirk agreed with Dr. Peterson's observation that it appears there are no scenarios where data from Capsule B would result in a conclusion that the embrittlement would not be acceptable for the five years of extended operation mandated by SB 846. Therefore the only thing that Capsule B data would influence would be a potential State of California decision to further extend the plant's operational life.

            Dr. Kirk reported on additional work to further investigate the finding from the Part Two of his Report that the Upper Shelf Energy may fall below the NRC 68 Joule screening criteria in about five years. Dr. Kirk stated he found that the unirradiated data samples from both the Unit 1 samples and those from the Palisades plant were in fact removed from the exact same weld. One set of specimens was tested associated with the DCPP surveillance program and another set of specimens was tested associated with the Palisades surveillance program. These separate tests produced two different estimates of Upper Shelf Energy which caused the normalization of the percent drop in Upper Shelf Energy to be different for Unit 1 and for Palisades. He reported that when one combines the separately normalized Unit 1 and Palisades data, it produced the outcome of falling below the 68 Joule screening criteria in about five years. In understanding more about the origin of the unirradiated samples came from, Dr. Kirk remarked it is not appropriate to treat those two sample sets as being different because they are all cut from the same weld. Consequently, he combined all the unirradiated data to get a unified estimate of Upper Shelf Energy of 132 Joule in the unirradiated condition for both Unit 1 and Palisades and then used that value to normalize the percent drop from all the data. This produced a curve which he displayed on a graph and compared to the NRC's assessment curve through the most limiting datum. This analysis showed that Unit 1 is not projected to fall below the 68 Joule screening criteria until the plant is far beyond the fluence that will occur even after sixty years. Dr. Kirk observed that based on this reanalysis he has revised the statement from the Part Two of his Report instead stating that the Upper Shelf Energy of Unit 1 is not forecast to fall below the 68 Joule screening criteria until sometime after sixty years of operation.

            Dr. Kirk reviewed the third topic of his work since February and observed that both Dr. Meshkati and Mr. Severance have raised questions about the adequacy of NRC embrittlement predictions and performance monitoring which were motivated by a number of reports and presentations that have been made by the NRC staff in the timeframe from 2021 to 2022. Dr. Kirk stated he reviewed the NRC's statements and the relevant documents and he commented there is additional information on the NRC's website. He stated he also wanted to assess what the implication of the NRC's concerns are, not with respect to the nuclear fleet in general, which is the NRC's job, but with respect to Unit 1 in particular. During 2021-2022, the NRC reviewed the accuracy of its Regulatory Guide 1.99 embrittlement prediction model and monitoring needs for long-term operation. He reported that if the NRC Staff finds a rule or regulatory guide needs modification then the Staff will requests permission from the NRC Commissioners to undertake that effort. Dr. Kirk observed in this request for rulemaking that the Staff outlined in very broad terms what it would do if it were given permission. Dr. Kirk remarked that the NRC staff submitted this rulemaking plan to the Commission to address their technical concerns in March of 2022, however, to date the Commission has not yet voted on that request which has been pending for the last two years.

            Dr. Kirk then explained the basis for the NRC's two main concerns and stated he would assess the impact, if any, of those concerns on Unit 1. He reported the NRC made the statement "although the probability of reactor pressure rupture remains generically low, the impact of embrittlement uncertainty on adequate safety margins and combined with insufficient performance monitoring, impact the staff's confidence in RPV integrity and challenge their finding of reasonable assurance of safety for long-term operation. To restore confidence in long-term RPV integrity, regulation and guidance changes are needed to implement use of an accurate embrittlement trend curve and to ensure continued performance monitoring through surveillance capsule testing." Dr. Kirk remarked this was a summary paragraph from a sixty or seventy page report so it obscures a lot of detail. He stated if one reads the NRC reports in detail, one comes to a conclusion that the NRC staff has two specific technical concerns underlying what's written in their rulemaking request. One concern is non-conservative predictions, meaning the level of embrittlement is under-predicted, made by the embrittlement trend curve and Reg Guide 1.99 Rev. 2 for long-term operation. The second concern is performance monitoring; here the Staff has stated continued deferrals of capsule withdrawals can lead to insufficient information to support structural integrity and licensing decisions. Dr. Kirk commented both of these concerns, at least at a high level, seem to have relevance to Unit 1. He displayed several slides with information giving more detail on the NRC's prediction of transition temperature shift and observed if the NRC's equation is accurate as a function of fluence for both base metals and welds then the majority of the data, ninety-five percent, should fall within the plus or minus two standard deviation tolerance bounds. He remarked that for welds, more or less, the data does this. For base metal, which he pointed out have a large amount of data at higher fluences, there is a downward trend seen where the prediction formula that the NRC requires shows non-conservative predictions, which he stated is of concern to the NRC. He commented that the fluence at which the embrittlement predictions starts to become non-conservative lies somewhere between 3 x 10¹⁹ and 6 x 10¹⁹ n/cm².

Dr. Kirk stated he wanted to point out an important point in that in his Report it was stated that after sixty years of operation Unit 1 will reach only 2 x 10¹⁹ n/cm². So while the NRC may needs to update its embrittlement trend curve to apply to the fleet in general, there should be no concern about lack of trend curve accuracy for Diablo Canyon Unit 1 because the fluence is not high enough.

            Dr. Peterson remarked he understands why there is data showing large fluence values because surveillance capsules are in location where they receive larger doses. Dr. Peterson asked Dr. Kirk which reactors have achieved such high dose. Dr. Kirk replied that for Unit 1 it was known basically from start-up that it would be a high embrittlement plant, because the pressure vessel had high copper content.  Accordingly, Unit 1 implemented a flux reduction program early in plant life to shield the welds from getting too much fluence. Other reactors with lower copper content did not take such early preventative measures and so may experience higher fluences. Also, other PWR reactor's designs are different and so may experience a higher fluence due to their design. To Dr. Peterson's comment, Dr. Kirk responded these higher fluences will only be seen in the United States during the end of first license renewal or second license renewal. He further commented this is why the NRC Staff has said in its rulemaking request that there is time to make the needed modifications to its equations and regulatory guidance.

            Dr. Kirk displayed a graph showing data on welds which he commented is the material of concern at Unit 1, the so-called limiting material, and he stated he limited the data on the graph to higher copper welds (greater than 0.07 weight percent). He stated he did not find it surprising that Reg. Guide 1.99 Rev 2 does not work very well as one gets to higher fluences and it also does not work very well for low copper material, because data on both high fluence and low copper plants conditions were rare in the calibration dataset when Reg Guide 1.99 Rev. 2 was developed in 1987. He observed Unit 1 has mediated its fluence because PG&E knew high fluence would cause the high copper weld in Diablo Canyon to potentially exceed regulatory screening criteria. He remarked what is seen on the graph is the residual or error plot versus fluence and he stated the graph shows all the high copper welds in the ASTM database. Dr. Kirk highlighted the weld 27204 data points, which are from the weld in Diablo Canyon Unit 1. He reported the graph shows all three Diablo Canyon points and the two Palisades data points are very near to a prediction residual of zero which is why he said he made his earlier statement that if one wanted to pick a material that shows Reg. Guide 1.99 Rev 2 is doing a really good job it would be the Diablo Canyon Unit 1 material. Dr. Kirk stated that in his judgment Reg. Guide 1.99 Rev 2 should be updated for technical reasons at some point, but that update will not really affect Diablo Canyon Unit 1 for reasons particular to its operation.

            Dr. Kirk reported on another area of NRC concern, and again stated that at a very high level this sounds similar to what's been going on with DCPP Unit 1, which is the repeated deferral of surveillance capsule withdrawals. Capsule B which was originally scheduled for withdrawal sometime in the mid-2000s has had its withdrawal deferred several times for reasons that the NRC allowed. He reported that PG&E now plans to withdrawal Capsule B in 2025 during refueling outage 1R25. Dr. Kirk confirmed that Capsule B must be withdrawn by 2028 to be compliant with NRC guidelines. He observed the NRC's requirements for surveillance capsules currently permit repeated deferrals of capsule withdrawals for plants seeking license renewal in order to obtain data for subsequent renewal periods up to eighty years while still using the limited amount of capsules that remain in the reactor vessel. Dr Kirk remarked for some plants these deferrals will allow operation after reactor pressure vessel fluence exceeds that of highest available surveillance data because some plants have low lead factor capsules. Dr. Kirk stated that for Diablo Canyon the lead factor is close to three to three and a half, so Diablo Canyon has never operated at a vessel fluence that exceeds its highest surveillance fluence. Conversely, if a plant has low lead factor capsules (lead factor between 1-2) and there is only one capsule left and that capsule is being saved to fulfill the requirement for getting data at eighty years, those plants may experience a period of operation where their vessel fluence exceeds their highest surveillance data. Dr. Kirk observed this is a problem which NRC staff have pointed out but it is not a problem for Unit 1. Even though DCPP Unit 1 has had successive deferrals of the withdrawal of Capsule B, Unit 1 is well monitored to and beyond its sixty year fluence.

            In response to Consultant McWhorter's observation Dr. Kirk agreed that where the NRC talks about adequacy of performance monitoring, which is not a criticism of the entire program, it is a criticism of how the program applies to a specific plant. Dr. Kirk further observed the NRC needs to decide how it wants to fix its requirements and Dr. Kirk stated he could not speculate as to whether the NRC will eventually decide on a targeted approach to address the problem only for certain plants or if the NRC will decides on a more wholesale change.

            Dr. Kirk stated that it is important from both an engineering and a safety point of view to understand that since 2011 DCPP has known about both Palisades data points. Both of those Palisades data points get DCPP Unit 1 to a fluence above their sixty year fluence. So since 2011 DCPP has had data forecasting thirty years in the future and Dr. Kirk reported data from Capsule B will extend that even further when it becomes available, well beyond eighty years of operation. So while the NRC has stated that it needs to further enhance its requirements in general, the staff's concerns about adequate performance monitoring are not pertinent to DCPP Unit 1.

            In response to Dr. Meshkati's question concerning how ASTM and the ASME consensus code compared to NRC regulations, Dr. Kirk explained the NRC sets the legal requirements for operation. In some cases the NRC establishes requirements completely on its own. In other cases, the NRC adopts as their own and incorporates into law requirements that have been established by either the American Society of Mechanical Engineers (ASME) or the American Society for Testing and Materials (ASTM). pertinent to reactor vessel integrity such endorsements have happened in two instances. The NRC has endorsed ASME Boiler and Pressure Vessel Code Section III and Section XI as the guidelines for how nuclear plants are designed and how nuclear plants operate, respectively. Dr. Kirk observed that is not to say the NRC has endorsed each and every section. In some cases they haven't endorsed some sections while in other cases the endorsement is partial. He remarked a running history of this issue is provided in 10 CFR 50.55a, but pertinent to reactor vessel integrity the NRC has endorsed ASME Section XI Appendix G, which informs plants how to calculate pressure-temperature limits for heat-up and cooldown. He reported the NRC has also endorsed ASTM E 185, 1982 or earlier editions if that is a plant's licensing basis, as the requirement for surveillance; this requirement is provided in 10 CFR 50, Appendix H.

            Dr. Meshkati stated he remembered a seminar, article or a chapter in a book about the evolution of ASTM practice from E 185 to E 2215 and he inquired if Dr. Kirk expects these ASTM standards or consensus standards to be revised, improved or updated in the near future. Dr. Kirk responded and stated he serves on the ASTM committee that oversees both of those standards and ASTM employs a continuous improvement process that requires its standards be evaluated for their current applicability and updated if needed every five years. Dr. Kirk stated he expects that E 185 and E 2215 to be revised in the future. Dr. Kirk stated he believes it is apparent from the document with the long history of E 185 he sent to Dr. Meshkati that the changes now are very minimal. He remarked the things that he expects to be new in the coming decade for surveillance concern the surveillance requirements of E 185 being tuned and refined based on the current generation of light water reactors that are operating in the United States. Dr. Kirk commented as the industry moves on to different light water reactor concepts, like small modular reactors and non-light water reactor concepts, he suspected one will see either new standards focused on the challenges presented by those different new reactor designs or perhaps appendices to E 185 and E 2215 to address those new reactor designs.

            In response to Dr. Peterson's request Dr. Kirk summarized the conclusions from his Report and stated the first conclusion is that the Unit 1 reactor pressure vessel complies with the NRC's embrittlement screening criteria through sixty years of operation. He reported there are then six more conclusions, and the short statement is that adequate data is now available to forecast Unit 1 embrittlement without resort to extrapolation. Data from Capsule B will provide additional information when it becomes available. The possible outcomes, as he just reviewed, are that if the Capsule B data are found credible by the NRC's criteria, Unit 1 will continue to comply with the NRC PTS requirements until past eighty years. If the dataset is not credible, then Unit 1 will need to perform additional analysis to justify further operation past fifty years, should PG&E wish to do so. Also, the past supplement concerning Upper Shelf Energy analysis was revised based on a better understanding of the data. This updated analysis shows that the Upper Shelf Energy forecast for Unit 1 is acceptable to beyond sixty years of operation. So the principal summary statement is that Unit 1 is safe to operate from an embrittlement perspective for the next twenty years.

            Dr. Kadak then thanked Dr. Kirk for making the time to make his presentation remotely from Japan.

XV      PUBLIC COMMENTS AND COMMUNICATIONS

            The Chair then opened the floor for comments and questions related to Dr. Kirks' report from members of the public and he confirmed the Committee will provide some extra time for Mr. Severance for his questions and comments.

            Mr. Bruce Severance was recognized. Mr. Severance stated the problem he has with the 2011 Westinghouse report is that the report comes to conclusions that are anomalous and contradictory to prior NRC research. He commented even though Dr. Kirk finds that the procedures are correct, and this may be in fact the case, the mathematical results themselves are anomalous. He observed in his view the Committee has focused on all the positives and has not looked at the negatives. Mr. Severance commented the 1987 NRC report that Dr. Kirk has mentioned which compared the Revision One's mathematical model to the Revision Two mathematical model clearly concluded that Unit 1 was more affected compared to every other RPV in the country because of the high copper and nickel impurities in the welds. He stated there were four different plants that had an underprediction of embrittlement by fifty to sixty-eight degrees RT_PTS value and PG&E was sixty-eight degrees.

            Mr. Severance stated the Revision One projections for which PG&E ran numbers as requested, he commented all plants in the United States were requested to respond to a generic letter issued by the NRC in 1986/1987, and came to the conclusion that Unit 1 had an RT_PTS value of 217° Fahrenheit (F), and NRC said DCPP Unit 1 had eighty-two years of operating time based on that. Then Mr. Severance said the NRC came to PG&E and said "We're really sorry. Your plant is most affected by the embrittlement issue, and you only have forty years of operating time, and the RT_PTS projected to end-of-life is going to be 270°F., not 217°F." Since then Mr. Severance stated PG&E has engaged in flux reduction strategies and issued a new report in 1992 suggesting RT_PTS was 258°F. In 2006 that was revised to approximately 259°F., with the NRC confirming the calculations and Mr. Severance stated that by November 2024 Unit 1 is supposed to be at 259°F. So if one looks at the range between 270°F. and minus 56°F. degrees for the unirradiated material, that's a 326°F. degree range and there is 11°F. of runway left, which is three percent based on that data alone.

            Mr. Severance observed the sum of squares[22] procedure, if it's done correctly, takes one back to 214°F., even lower than the 1986 calculations which the NRC said were the worst underprediction in the country. He reported there is a graph on page 56 of that paper which shows there is a seven-fold underprediction of pressurized thermal shock based on that model and he questions how it could be possible that DCPP is going back to a number that is lower than the 1986 number that the NRC confirmed was seven times an underprediction, compared to Revision One. Mr. Severance remarked he needs a reasonable explanation as to why that no longer matters and he has not received one to this day and he remains concerned. He remarked as a person who lives here and owns a home he does not understand why we're playing the game of financial risk to the State of California for one, and financial risk to the entire economy of this County. He remarked if something bad happens it would be a bad day and $50 billion worth of real estate would be lost as well as the entire grape industry and all the agriculture. Mr. Severance observed this is too big a risk to take a chance on based on anomalous results just because someone says the sum of squares is an okay procedure, which he stated he does not believe. He observed even if it is in accordance with NRC rules, the NRC itself, it one looks at Wichman 95, Wichman even questions the underpredictions that he was starting to see in 1995.

            Mr. Severance commented Dr. Kirk has stated repeatedly in his report and in response to many of Mr. Severance's comments that because it says "shall consider" in 10 CFR 50.61(c)(2) that one is required to use this sister plant data. Mr. Severance stated he has never said sister plant data cannot be used and he remarked sister plant data can reduce uncertainties and in any case where it reduces uncertainties it should be used. But he remarked consideration of all the data, not just sister plant data, is not a mandate to perform the sum of squares procedure, 10 CFR 50.61 equation 5, that allows this reduction from 259°F. down to 214°F.

            He stated the last thing he is going to say is we should be looking at all the data and all the reports that pertain to whether or not the sum of squares procedure is appropriate under these circumstances. He reported he has read the capsule reports several times and they contain terminology that is quite ambiguous. He remarked he made an error because in the summaries where transition temperature is given he assumed that these were RT_PTS values but the RT_PTS values are not stated in any of the three reports and he questioned why that is not required? He reported in 1986 PG&E was required to submit a calculation of RT_PTS at end of license and was required to update that calculation in 1992 and 2006. He questioned why this data is it not in the capsule reports which only contain adjusted RT_NDT values. He commented there is vague reference to transition temperature, but RT_PTS is not stated although it is given in the 2011 Westinghouse report. Mr. Severance stated he wanted to understand and to see the math to know what the conclusions were of those three reports and why that data isn't there. He remarked this data is shown on graphs but he does not find it in the reports and he stated that is a problem and an anomaly for him as the whole point of that report is to estimate embrittlement at end of life and Mr. Severance remarked most people read it the same way as he did, thinking that the references to transition temperatures meant one thing. He commented he suspected the numbers were off and now he realizes they were really just giving the measured values for the transition temperature. He remarked when he started putting it into the equation, which is when he realized he has been misunderstanding these reports all along and they don't state the RT_PTS at end-of-life. He closed his remarks by stating he would appreciate answers to his questions.

            Ms. Marilyn Brown was recognized. Ms. Brown stated she and her family have lived in San Luis Obispo County since 1972 and she has had concerns about the safety of having a nuclear generating plant located nearby her town. She stated her concern was heightened during and after the Fukushima disaster. As a lay person she observed it is difficult to decide between nuclear experts on safety facts as she reads and try to understand the reports made by Drs. Kirk, Macdonald and Bird. She stated she found Dr. Kirk's position on DCPP Unit 1 which she described as "It [DCPP Unit 1] is no different than any other early constructed plant." She commented Dr. Kirk has missed the important fact that according to the NRC 1987 study she referred to, it is claimed that Unit 1 "is the most embrittled reactor in the U.S. fleet." In 2022 Ms. Brown remarked the NRC stated Unit 1 embrittlement was understated. She asked in addition to aging weld impurities and multiple adjacent seismic faults and the possible need to quickly shut down the reactor, when was the last ultrasonic or surveillance testing done and she stated it was her understanding this was twenty years ago and if that was the case it is long overdue. She inquired when persons living in Diablo Canyon's evacuation zone can be assured that the requisite testing has been done and the public notice has been given. She commented on the ballooning cost she and other taxpayers will be paying for years to keep the plant operating when alternatives are at hand. She again commented as a layperson it is difficult to decide between the experts, between Drs. Kirk, Macdonald and Bird, because she stated she does not understand a lot of what they've said and she wants the Committee to explain to her what she does not understand. She then thanked the Committee.

            Ms. Sherry Lewis from Mothers for Peace was recognized. Ms. Lewis commented she spent many hours trying to read and understand the various reports including Mr. Severance's reports and she has questions. One question concerns what is shelf energy and regarding the other she stated it is her understanding that the reason there are coupons or capsules, which are in long pipes filled with samples of the metal that the vessel is made of including the welds, is that over time the capsules are taken out and various pieces of metal are checked to see how embrittled they are and not just how embrittled but how much longer will they survive or will work in the plant. She explained when they are placed in areas where there is more fluence, one can then predict further into the future. She inquired how can these capsules be removed and not used and she observed Capsule B has not been used and how can the material inside Capsule B be measured if it is not taken out and checked and she asked isn't that what must be done. She observed Dr. Kirk is convinced that Capsule B predicts that the plant will survive safely for sixty years but how can he know because of something that happened many years ago. Ms. Lewis commented she suspects that a reason for not having withdrawn Capsule B is that PG&E already knows that the result will not be good. She remarked it has not been checked for twenty years, so it might well be that it's a bad number and PG&E does not want to shut the plant down. She observed Dr. Kirk accepts whatever the NRC regulations are and he says the regulations imply that everything is safe, but he admits that there are a lot of changes that need to be made. Ms. Lewis stated that means there's something wrong with the regulations and until the regulations are changed they don't fit the reality. She questioned why Dr. Kirk is sanguine that the regulations work when he knows they are going to be changing them to make them a little more careful. Ms. Lewis commented she is suspicious of all this and she does not believe the plant is safe for another twenty years.

            Dr. Kadak responded and observed that Dr. Kirk did not say he knew the results from testing Capsule B. Dr. Kirk reported he did a sensitivity study to see what possible outcomes there were when it is tested, what they could be in terms of embrittlement. But that Capsule B would demonstrate the equivalent of over eighty years of fluence.

            Ms. Linda Seeley of Mothers for Peace was recognized. Ms. Seeley observed Dr. Kirk said that Capsule B will be required to be removed by 2028 for extended operation. She remarked that as far as she is aware extended operation of DCPP begins on November 3, 2024, as the operating license [for Unit 1] expires on November 2, 2024. She then asked how it can be that four years after the license expires is a proper time to look at that capsule. She stated she understands PG&E is planning to remove Capsule B if they can in Spring of 2025 which is already beyond the license term. Ms. Seeley observed the public is supposed to just trust that everything is absolutely fine at Diablo Canyon for four years after the expiration of the license. Ms. Seeley stated the proper action for the DCISC would be to recommend shutting the plant down on November 2nd, 2024, in two weeks, and then do the testing that's needed and if it turns out that everything is okay then possibly consider starting it up again.

            Mr. Aaron Pierce was recognized. Mr. Pierce stated he is a Professor of Mathematics at Cal Poly, although he was not speaking as a representative of Cal Poly but as an individual. He stated he is also director of the Initiative for Climate Leadership and Resilience at Cal Poly. He remarked in his understanding the reduction in projected values from RT_PTS 251°F. down to 214°F. arises from using a larger set of data, including two sets of data from the Palisades plant on the theory that more data reduces uncertainties by using an allowed sum of squares procedure. He remarked this would be a correct assumption on the basis that the samples that one is drawing from are truly random. However, he commented the NRC has reported that DCPP is more strongly affected by the embrittlement issue than any other RPV in the U.S. including Palisades. He stated he understands that the incorporation of sister plant data is in accordance with NRC procedure but the existence of this recognized embrittlement issue means that including such data through the sum of squares systematically biases one's data as it is known not to be random. He stated as such it casts serious doubt on the integrity of the results and makes any decision on these results appear to be premature and ill-advised. Professor Pierce strongly encouraged the DCISC to pursue further testing along the lines of what was mentioned by the previous commenter to provide grounded truth before recommending perhaps another twenty years of further operation based on what appears to be a shaky statistical procedure.

            Dr. Gene Nelson of Californians for Green Nuclear Power was recognized. Dr. Nelson commented he finds it very troubling and it is his impression that the people that are doctrinairely opposed to the continued operation of the plant choose to fail to understand basic mathematical concepts that the Committee is well aware of. Namely one starts with the premise that samples are over-irradiated and from that you can determine useful life of a reactor pressure vessel based on those simple mathematical operations. Dr. Nelson stated some people think if it is repeated that this is not right, that somehow or another that is going to convince the DCISC that they're right and plant advocates are wrong. He stated he finds this troubling because it's basically saying ignorance triumphs and that is the problem here. He observed, in other words, if people are not willing to learn the physics and the mathematics and then they say there is something wrong, they are not presenting anything that makes sense from a scientific or engineering perspective and unfortunately this has happened frequently.

            Ms. Linda Parks was recognized. Ms. Parks stated she was with Mothers for Peace and supports their positions. She distributed a report that showed that in 2013 DCPP Unit 1 was considered one of the most embrittled plants in the nation.[23] She commented State Senator Laird who helped usher in SB 846 and Senator Laird has stated in a letter to the San Luis Obispo County Board of Supervisors, in which she stated Senator Larid opposed extending the license to twenty years, that the major provisions of SB 846 include required seismic and other safety review processes so that the continued safety of workers and surrounding residents would be considered in the extension of the operation of an aging facility. Ms. Parks observed the safety analysis will not be completed until the embrittlement of Unit 1 can be tested, and yet PG&E's postponement of the Capsule B testing and similar postponement of ultrasonic imaging is tantamount to flying blind. She commented Unit 1 has been known from all prior reports and assessments to be severely embrittled, yet surveillance testing has not been performed since 2003 and ultrasonic inspections have not been performed until 2005. Ms. Parks observed when PG&E was required to do that testing they said that they tried to retrieve Capsule B, but the reactor core barrel blocked access and the access plug to the capsule did not operate as intended and the tool would not engage in that location. She stated that gives her a lot of concern. Ms. Parks remarked the NRC itself has reported that by not testing it gives them a lack of confidence, and she stated the NRC report concluded specifically that in regard to operator delays on capsule testing, which delays capsule withdrawal for an extended period with the possibility of no future data, represents a lack of performance monitoring. The embrittlement issue will eventually, after about ten years, impact the staff confidence in the integrity of the reactor pressure vessel in long-term operation, i.e., both safety margins and performance monitoring may be impacted. Ms. Parks remarked it's been seventeen years and one cannot do it by testing other plants because as we've heard, Diablo Unit 1 has welds with copper and nickel impurities. She stated her belief that there is potential for catastrophic results, according to Mr. Severance, from underestimating and underpredicting what could happen. She stated the public needs to know, the NRC needs to know, PG&E needs to know and you cannot extrapolate the determinate, you need to actually do the test.

            Ms. Carol Hisasue was recognized. She stated she was speaking as a local resident who lives within ten miles of Diablo Canyon. She observed whether she understands the math or not, she can see that Dr. Macdonald's and Dr. Kirk's studies come to vastly different conclusions. One concludes that Unit 1 needs to be shut down now, while the other concludes that everything is "hunky-dory" now and for many, many more years. She observed there is a big discrepancy between the two studies and with this kind of uncertainty, and in a situation where highly radioactive materials are being used and could be released, would it not be the prudent decision to error on the side of caution and safety? She commented if Dr. Kirk is wrong and you continue to operate Unit 1 and if there is a kind of event like an earthquake that required immediate shutdown the thermal shock would damage the reactor pressure vessel causing a catastrophic radioactive release and a disaster like that would not only make the San Bruno accident pale in comparison, but the effects would last for generations. She commented if Dr. Macdonald is wrong PG&E would lose money from not being able to operate Unit 1 until it can be properly tested, something that's been postponed time and time again and monetarily this loss also pales in comparison to what the cost of a nuclear disaster would be. Ms. Hisasue remarked the common narrative of the Fukushima disaster is that it was the tsunami inundation of the back-up generators that led to meltdown, but Ms. Hisasue stated the truth is that it was complacency and that the disaster was completely preventable, as in February 2011, about a month before the huge earthquake and tsunami, the Japanese Nuclear Regulatory Agency extended the operating license of Fukushima Daiichi, despite expressing reservations about a dubious maintenance record and concerns about stress cracks in the back-up diesel generators that left them vulnerable to inundation. She remarked if TEPCO had not brushed away the possibility that two back-up generators would fail simultaneously and if there were more robust inspections, transparency and accountability, all things necessary for healthy safety culture, the triple meltdown catastrophe that's still ongoing would not have happened. She observed there were other nuclear plants along the same coast even closer to the epicenter that survived the same earthquake and tsunami. Ms. Hisasue asked the Committee to please shut down Unit 1 until the structural integrity of its pressure vessel, not just the welds, but the entire vessel can be assured. She remarked it is not just in the interest of people like her who live here, but it's in the interest of the employees and the shareholders of PG&E.

            Ms. Jane Swanson was recognized and identified herself as one of several spokespersons for San Luis Obispo Mothers for Peace. She observed the question before us regarding the safety of Unit 1 pressure vessel is who has the burden of proof. From reading and hearing the testimonies of Dr. Macdonald and Dr. Kirk, plus observing the responses of the Committee, it appears to her as a layperson that the Committee is placing the burden of proof on Dr. Macdonald to prove that the embrittlement of the pressure vessel does not meet safety standards. But given both the precautionary principle and the truly catastrophic consequences should the pressure vessel fail it seems to her that the burden of proof belongs to PG&E to prove beyond a reasonable doubt that the pressure vessel is sound. This has not been done and others have made the case about the need for accurate testing. She stated she was quoting from Dr. Macdonald and stated unless and until the NRC establishes that the Unit 1 pressure vessel can operate with a reasonable degree of safety, it has no basis to permit continued operation in a license renewal term. Ms. Swanson stated that she wanted to clarify that Dr. Macdonald, while serving as an expert witness for San Luis Obispo Mothers for Peace, is not anti-nuclear. She stated she is anti-nuclear but Dr. Macdonald is not and to the contrary Dr. Macdonald has taught nuclear engineering at U.C. Berkeley for many decades. But, Ms. Swanson commented, his expert opinion, as someone who approves of nuclear, is that Unit 1 at Diablo does not meet safety standards. Ms. Swanson remarked Dr. Kirk disagrees with Dr. Macdonald on what data and what graphs are applicable in evaluating the pressure vessel and he reaches different conclusions. Ms. Swanson commented she understands that scientific uncertainty is a given but in this case the stakes are far too high to impose continued operation of those living downwind from the reactor. A population that, depending on the weather conditions at the time of a radiation release, would certainly extend far beyond Diablo Canyon and far beyond San Luis Obispo County, and very possibly affect neighboring states. Ms. Swanson observed her last few sentences echo what Ms. Hisasue just said so very well. She called upon the Committee to show its independence and to show its priority for safety. She remarked the DCISC is an independent safety committee and she would like to see it act accordingly and not endorse continued operation of this unacceptable reactor.

            Ms. Diane Curran was recognized. Ms. Curran stated she is an attorney representing San Luis Obispo Mothers for Peace and she has worked closely with Dr. Macdonald on his declaration to the NRC in support of a hearing request on the latest extension to the surveillance program for Diablo Canyon, and she has spoken to him recently. Ms. Curran reported Dr. Macdonald is now in a shelter in Florida during Hurricane Milton or she believes he would be on line tonight. Ms. Curran stated one of the last things Dr. Macdonald said to her was they don't have the data. She commented she was shocked to hear Dr. Kirk say that the issue is well covered in terms of surveillance data and she commented Mothers for Peace profoundly disagree. She observed the last time that PG&E removed a surveillance capsule from Unit 1 was in 2003, more than twenty years ago and the data from that capsule was declared by PG&E to be not credible and that was when PG&E started taking data from Palisades, which she described as a questionable comparable. She stated it is important to recognize that Dr. Macdonald is not anti-nuclear, but with all his many years of experience in nuclear reactor materials and corrosion chemistry Dr. Macdonald is of the firm opinion that this reactor should not be allowed to operate until PG&E gets the data that they've been putting off for twenty years. Ms. Curran stated she wanted to also mention the legal issue of why it is that so few capsules have been taken from Unit 1 and that removal of Capsule B was planned at a time after the expiration date of the Unit 1 operating license. She reported in 2006 PG&E applied to NRC for a three year extension of its operating license to recover the time that PG&E tested Unit 1 at full power and in exchange the NRC technical staff asked PG&E to upgrade the Unit 1 surveillance program from three capsules to five capsules and PG&E agreed to this in order to get that three year extension on its current operating license. Then sometime in 2008-2009, when PG&E decided that it was going to go ahead with license renewal, PG&E began maintaining that it was a three capsule program and that Capsule B was only relevant to the license renewal term and could be taken out at any time after the forty-year operating term or later and the NRC went along with this. She commented Mothers for Peace is challenging in federal court what she described as a shell game, has briefed the issues, and will be having an oral argument in early November 2024. Ms. Curran acknowledged that it is always difficult to win at the Court of Appeals, but she believes whether Mothers for Peace prevails or not, it is easily discerned from the factual record that PG&E has been delaying withdrawing Capsule B and has even taken advantage of a license amendment in which it promised to withdraw Capsule B by 2009. Ms. Curran urged the Committee to make sure it gets this data before allowing Unit 1 to continue operating.

            Dr. Peterson commented this has been probably one of the most extensive sets of public comments that the Committee has had the opportunity to receive. He observed this is an extraordinarily important set of topics and the Committee's next step will be for its Members and Consultants to provide responses or additional information relevant to questions that were asked, following which there will be a vote on including Dr. Kirk's Report and the exchanges of information received by the Committee in the 34^th Annual Report. He reported there is an item on the agenda for the following day for the Committee to discuss all of elements of the Annual Report the draft of which has multiple recommendations.

            Dr. Kadak displayed a graphic from Dr. Kirk's presentation which he stated shows the adequacy of the data to be obtained from Capsule B obtained through sixty years of operation for this plant. Dr. Kadak reported that in the sensitivity study Dr. Kirk performed for Capsule B's removal one cannot know whether the results will be credible or not credible relative to what NRC describes as credible. If the data is credible, namely it fits the expected curve, the plant is good for over eighty years. If it's not credible Dr. Kirk concludes the plant probably needs to do additional analysis after fifty years. Dr. Kadak observed the data is there to make a very clear case for acceptable performance out to sixty years, but we have a datapoint that's beyond, actually beyond forty and beyond sixty that will allow for continued operation and he stated that is a critical point and what happened in 1987 or 2011 is not relevant in terms of available data to make a prediction.

            Assistant Legal Counsel Rathie requested that members of audience maintain respectful decorum and abide by the rules as stated earlier in this public meeting. He commented after the June 2024 public meeting the Committee was criticized for being unfair to both supporters and opponents of extended operations and must in all instances enforce its rules fairly and equitably.

            Dr. Kirk observed the concept of credibility as used by the NRC in context of data on reactor vessel embrittlement is explained in his Report. Dr. Kirk remarked the key point that seems difficult for people to accept is that because of the way the capsules are designed, even tests made twenty years ago are pertinent far into the future. Dr. Kirk stated he wanted to respond to a comment Mr. Severance made at the beginning of the public comment period that the 2011 forecast from the Westinghouse Report is somehow anomalous in his point of view because of the statements made in the 1987 NRC Report that compared Reg Guide 1.99 Rev 1 with Reg Guide 1.99 Rev 2. Dr. Kirk commended Mr. Severance for his ability to digest a lot of information which is important but Dr. Kirk observed it is important to recognize that the statements by the NRC in 1987 were comparing the predictions of the Revision One formula to the predictions of the Revision Two formula for the chemical content and operating temperature of Unit 1 and within that context, what Mr. Severance said is completely correct - that the Revision Two formula predicted a far higher level of embrittlement for Unit 1 and therefore a far shorter lifetime before it passed the PTS screening criteria. He remarked that is all absolutely correct. However, if when one goes to 2011, what's different is that now there is data that is shown on the graphic Dr. Kadak displayed. Dr. Kirk reported when you have data from surveillance capsules, the NRC allows you to essentially adjust the NRC's prediction formula to go through the mean of the data and then you use the mean plus two sigma upper bound to account for uncertainty on those data. Dr. Kirk reported what has been found after thirty years of testing of Unit 1 is that the prediction, without the insight of measured plant-specific data for Unit 1, made by the Revision Two formula did indeed predict a more severe situation which PG&E has been living with ever since. But as DCPP collected data, it was found that the Revision Two formula was actually a little bit too pessimistic and when the data is used to adjust the formula, as he showed, one gets to the predictions we have today. Dr. Kirk commented he does not believe it is correct to call a 2011 prediction, based on a predictive formula as adjusted to data, anomalous with respect to a 1987 comparison of just two formulas.

            Dr. Kirk observed with respect to Mr. Severance's comment about no RT_PTS values in surveillance reports that he would also like to see that data in the reports, but that is not the purpose of a surveillance report which just reports the data and the PTS assessment is done in a separate report.

            Dr. Peterson observed there is also a proposed recommendation in the 34^th Annual Report that PG&E should remove Capsule B during outage 1R25 in spring 2025, and he urged DCPP to make sure that happens. He stated based on the analysis from Dr. Kirk the data from Capsule B would not affect the five year extension mandated by Senate Bill 846, but it would provide information that could be relevant to any decision to potentially further extend the operating license.

            The Chair thanked everybody for being polite at this meeting and commented the Committee did have a bad experience at its last public meeting and has found that its usual level of informality for public comments does not work well for these types of issues which are complex and involve significant issues that relate to the safety of the plant. In fact, Dr. Peterson remarked informal discussions can create problems in a public forum because at a certain point it becomes unfair to all participants and so when the Committee does consider these more difficult and controversial issues which are complex and quite important, it is forced to use a more conventional set of rules about public engagement and public comment.

            Dr. Peterson then explained the nature of the vote the Committee will be asked to make this evening which will be to consider directing that Dr. Kirk's Report now be included in the 34^th Annual Report with the subsequent questions concerning specific conclusions and recommendations associated with the Dr. Kirk's Report to be taken up the following day along with other topics in context of its consideration of approval and adoption of the DCISC's 34th Annual Report.

            Mr. Rathie explained concerning the considerable record that has been made in this matter, the Committee accepted Dr. Kirk's Report into the Committee's record in this matter at its February 2024 public meeting. In response to Dr. Meshkati's inquiry Mr. Rathie gave his opinion that the operative effect of accepting and receiving is the same. Consultant McWhorter remarked that the nature of the action pending this evening leaves open the question of whether to modify any of the conclusions or recommendations from the Executive Summary as included in the version with the agenda packet which was made available prior to the public meeting.

            On a motion made by Dr. Budnitz, seconded by Dr. Meshkati, the Committee unanimously approved the inclusion of Dr. Kirk's two part Report in the Committee's 34^th Annual Report.

            Dr. Meshkati then thanked Dr. Kirk for his two volume report which was written before Dr. Meshkati joined the Committee. Dr. Meshkati stated when he joined the DCISC on July 1, 2024, he asked some specific questions about page 31 from an NRC final report dated March 8, 2022 that Mr. Severance also referred to concerning the impact of embrittlement on reactor pressure vessel integrity from a risk informed perspective. Dr. Meshkati remarked he asked some questions of Dr. Kirk and Dr. Kadak based on that report and they graciously responded to him and their response is now available on the DCISC website. Dr. Meshkati stated after a Zoom meeting with the Committee's consultants he asked for some follow-up information which Dr. Kirk graciously provided. Dr. Meshkati stated he would like to thank Dr. Kirk who will not be present tomorrow and Dr. Meshkati remarked that it doesn't mean that if Dr. Kirk is not present and his report does not get "accepted" that Dr. Kirk has not done a great job. Dr. Meshkati observed Dr. Kirk did a great job and he thanked him for providing what he described as a fantastic response to his questions. Dr. Meshkati remarked he still has some further questions about the consensus and other codes and the NRC.

            Dr. Peterson observed at this point the Committee has concluded the business for the day and will be reconvening this public meeting tomorrow at 9:00 a.m. He thanked the members of the public and apologized for the need for us to hold very firm to the time limits and the restrictions on ability to provide public input. He remarked that has been an uncommon practice for the Committee, but given the experience at the last public meeting where there were clear problems around the fairness of the process that the Committee was using, introducing formality in this case was necessary.

XVI     ADJOURN EVENING MEETING

            The Chair adjourned the evening session of the DCISC at 7:33 p.m.

XVII   RECONVENE FOR MORNING MEETING

            The morning meeting of the DCISC, the second day of the 109^th public meeting was convened by the DCISC Chair Dr. Per F. Peterson at 9:00 a.m.

XVIII  COMMITTEE MEMBER COMMENTS

            Dr. Meshkati wished everyone a good morning and remarked that yesterday was his first day on the Committee during a public meeting and he thanked those in the audience for their contributions and input, both in person and by email.

            Dr. Peterson requested Assistant Counsel Rathie to review the protocol for those present in person and online to address remarks to the Committee. Mr. Rathie reviewed the following, which were previously discussed at the beginning of the meeting yesterday:

→        Speakers should come to the podium and identify themselves;

→        Speakers will be recognized by the Chair in order, first from among those present in the    room and then among those attending virtually;

→        Remarks will be limited to four minutes, but this may be varied for each session;

→        Comments from public officials may be taken before those of members of the general public;

→        Speakers may not cede their time to other speakers;

→        Groups may be asked to appoint a spokesperson;

→        Each speaker may only address the Committee once under either the time for items not on the agenda or when a matter listed on the agenda is heard;

→        The DCISC Chair reserves the right to stop any speaker if he or she believes the speaker is out of order;

→        The Committee reserved the right to modify the rules in the interest of conducting an effective meeting including granting extra time to certain speakers upon request;

→        Writings used in conjunction with remarks should be provided to the Committee's Legal Counsel; and

→        Email comments received will be read into the record subject to the time limit.

                      

XIX     PUBLIC COMMENTS AND COMMUNICATIONS

            Dr. Peterson invited members of the public to address the Committee on matters not on the agenda for this meeting.

            Dr. Gene Nelson was recognized. Dr. Nelson stated he is a former science and engineering professor and he has been attending public meetings of the DCISC for 17 years and he views his attendance as an important activity. Dr. Nelson remarked that early in his career he became aware of a program called Megatons to Megawatts which resulted in the equivalent of 20,000 Soviet warheads being used to power U.S. nuclear power plants which he described as the equivalent turning of swords into plowshares. Dr Nelson commented he has visited the ISFSI several times and to him the spent fuel storage canisters are monuments to world peace. Dr. Nelson reported he received a Presidential Citation from the President of the American Nuclear Society in 2022 for his advocacy and he remarked he continues to support conclusions based on science and engineering. He reported the letter from which he read sections during the previous day has now been received into the NRC's records as ML24281A106. Dr. Peterson thanked Dr. Nelson and he confirmed there is material that was once in nuclear weapons aimed at the United States which is now in storage at DCPP.

XX      ACCEPTANCE OF MINUTES

            This item concerned review and acceptance of the Minutes of the Committee's June 20-21, 2024, public meeting conducted in Avila Beach and as a Zoom Webinar. A draft of the June 2024 Minutes was included in the public agenda packet for this meeting. Dr. Peterson remarked that the use of bold text in the Minutes is important as it captures and describes some action or commitment on the part of the Committee which is then often included on the Committee's Open Items List for follow up. The Members and Consultants reviewed the Minutes and provided corrections and substantive changes to certain sections of the Minutes which will be included in the final version of the June 2024 Minutes. Editorial and typographic revisions were provided to legal counsel for incorporation in the final version. The Members and Technical Consultants then conducted a page-by-page substantive review of the June 2024 Minutes and discussed some of the follow-up actions to be taken, provided clarification concerning errors and accuracy of certain statements in the Minutes, and made editorial comments and changes concerning the draft of the June 2024 Minutes.

            Mr. Rathie thanked Ms. Denise Righetti the Wellington & Rathie law firm's office administrator for her work on the transcript of the June public meeting which he stated exceeded 400 pages and is an invaluable tool for purposes of creating the meeting Minutes and he also thanked AGP for providing a rough transcript of the proceedings immediately following the meetings which is created from the closed captioning feature and has proven to be quite helpful.

            On a motion by Dr. Budnitz, seconded by Dr. Meshkati, with Dr. Meshkati abstaining, the Minutes of the June 2024 public meeting were accepted by the Committee and in their final corrected form will become a part of its 34^th Annual Report.

XXI     ACTION ITEMS      

A.        Discussion of Issues on Open Items List.

            Dr. Peterson requested Consultant Wardell lead a review of items on the Open Items List, which he described as an important and dynamic tool used by the Committee to set priorities, track and to follow standard topics, emergent issues, new concerns, information requests and activities identified for subsequent action or receipt during fact-finding or public meetings. Dr. Budnitz remarked from time to time items are added to and followed up on in the Open Items List review based on input from members of the public. Mr. Wardell stated newly added or changed items were shown in red italics while items for which follow up is scheduled prior to the October 2024 public meeting were shown in yellow, and items which were deleted or changed were shown in strike-out on the version of the Open Items List included with the agenda packet and certain items on the list were identified for closure.

Items discussed or concerning which action was taken included the following:

Open Items List[24]

Item	Re:	Action Taken/Next Action
CO-13	Operation in Differing Modes incl. Load Following	Close
EN-1	Long Term Projects	Prior to 1R25
HP-1	Human Performance/Behavior	Add NM to 2Q5FF
RA-6	NRC 50.59 Risk Informed Regulation LAR	Add RJB 11/24FF
SC-15	FLEX Procedures - Post-Earthquake/Fire Dept.	Update/Modify -Rev Use in PRA re Action Timing Add NM (do not close)
SE-14	Monitor Work of IPRP	Monitor Future Reports
EO-9	Review New Seismic Safety Info from IPRP	Monitor Future Activities
EMB-1	U-1 Embrittlement Issue	Close
EMB-2	Dr. Kirk to Review of Capsule B Outcomes	Close
EMB-3	Rev Compliance post Capsule B Analysis	Remains Open
EMB-4	Review Any Information from Third Parties	Close to EMB-5
EMB-5	Review Any All Information from Third Parties [delete Any replace with All]	Remains Open Remove ref to EO-9
EMB-6	Review & Comment on Any All New Information in LRA [delete Any replace with All]	Remains Open 2Q25FF
EMB-7	Review Alternate Methodology for Capsule B Data	Close

DCPP Systems/Programs Reviewed Periodically

Item	Last Reviewed	Next Action
RHR (Residual Heat Removal System)	Jan 2021	Nov 24 FF
10 CFR 50.59 Program	July 2021	Nov 24 FF

            During discussion of the Open Items List Mr. Dave Houghton, a member of the Diablo Canyon Decommissioning Panel, was recognized. In response to Mr. Houghton's comment regarding DCPP's capability to operate in load following modes Drs. Peterson and Budnitz responded that the plant is capable of load following and on occasion power is curtailed to address current conditions and improve overall safety such as during winter storm activity but the key operational issue involves the addition and removal of boron to the reactor coolant and power changes do place certain undesirable stresses on the plant. Dr. Peterson observed French nuclear power plants have had their control rod systems modified using gray control elements[25] and therefore do not need to add or remove boron and Dr. Budnitz remarked the French plants having made those modifications are able to rapidly load follow. Dr. Peterson remarked that were DCPP to plan for routine frequent changes in power, major modifications would be required. Dr. Budnitz in response to Mr. Houghton's inquiry commented DCPP was designed to follow the ramp rates consistent with daily load following, but its routine operation does not contemplate that and he agreed that were these operations to be optimized major modifications would be needed. Consultant McWhorter remarked that a nuclear power plant is not capable of load following as quickly as a gas plant and he remarked many people think of load following as requiring ramp rates that are higher than the plant would normally do.

            Dr. Gene Nelson of Californians for Green Nuclear Power was recognized. Dr. Nelson remarked on another engineering issue regarding load following in that there is a necessity for synchronous grid inertia and DCPP is the largest contributor to synchronous grid inertia on the grid which maintains stability in response to random transients and this is an argument against changing from baseline to baseload operation.

            Ms. Sherry Lewis with Mothers for Peace was recognized. Ms. Lewis asked that the items under "EMB" concerning reactor vessel embrittlement not be closed. Consultant McWhorter asked the Committee to determine in its review what items under EMB are to be closed and which will remain open. The Committee Members confirmed relative to Open Item EMB-7 that Dr. Kirk has in his report addressed use of alternate methodologies for analyzing Capsule B data.

            On a motion made by Dr. Budnitz, seconded by Dr. Meshkati, the Committee Members unanimously approved the Open Items List as amended during their discussion.
                                                         

XXII   DISCUSSION, DIRECTION AND ACTION, AS APPROPRIATE, BY THE COMMITTEE, CONSULTANTS AND COUNSEL          

C.        Public Outreach, Site Visits and Other Committee Activities, Scheduling and Confirmation of Future Fact-Finding Visits and Public Meetings.

            Mr. Rathie reported this agenda topic is for Members or Consultants to make a brief report on their activities or site visits since the last public meeting and to then turn to future scheduling of public meetings and fact finding visits. He commented he recently attended a remote meeting with Dr. Budnitz and representatives of the California Attorney General. Dr. Peterson reported the Committee had hoped to be able to hold a plant tour with members of the public at this meeting, but due to training exercises the Simulator facility was unavailable for a visit. He suggested that consideration be given to conducting a public tour in conjunction with the February 2025 DCISC public meeting as the public tours have in the past been an important aspect of the Committee's public outreach activities.

            Mr. Drew Houghton a Member of the Diablo Canyon Decommissioning Engagement Panel reported the panel recently held a meeting concerning the storage of spent fuel and public attendance at the Panel's meetings has been less than in previous and the panel is now exploring ways to increase public engagement and awareness of its meetings and he remarked to the extent the panel could cooperate with the DCISC in this effort it would try to do so.

            Dr. Peterson commented it would be good if Dr. Meshkati could review the dates for Committee activities which were necessarily selected without his input. The Members then discussed and confirmed future public meetings of the DCISC for February 19-20, June 10-11, 2025 (subsequently changed for June 11-12), and October 22-23, 2025, and the Members and Consultants then scheduled a public meeting for February 18-19, 2026.

            Fact-finding visits were then confirmed, subject to confirmation by DCPP that the plant can support the visit on the selected dates, and scheduled as follows:                            

[2024] November 12-13 RJB/RDM; December 11-12 PFP/RFW.

[2025] January 21-22 NM/RDM; March 18-19 RJB/RFW; April 23-24 NM/RFW during 1R25; May 7-8 (PFP/RDM); July 29-30 PFP/RDM; August 12-13 NM/RFW and September 16-17 RJB/RDM; November 18-19 (RJB/RFW); December 9-10 (PFP/RDM).

[2026] January 20-21 (NM/RFW).

 B.       Documents Provided to the Committee:

            A list of documents provided to the Committee since its last public meeting in June 2024 was included in the agenda packet for this meeting.. Outgoing and incoming correspondence to and from the Committee is on file at the office of its Legal Counsel.

X (Cont'd.)     CONSULTANT REPORT & RECEIVE, APPROVE, AND AUTHORIZE TRANSMITTAL OF A FACT FINDING REPORT TO PG&E

            The Committee then returned to the matter of considering for approval the August 27-September 24-25, 2024 Fact Finding Report which was tabled following discussion yesterday during the afternoon session. Mr. Rathie reported that with Consultants McWhorter and Wardell a revised version of the report's conclusions regarding seismic issues based on the discussion yesterday was drafted last night and distributed individually to the members with no exchanges between them having taken place concerning this draft. Copies of the draft with the revised conclusion were provided in the meeting room. Dr. Peterson remarked he did not have the opportunity to review the prior version of the report proposed for adoption yesterday and was therefore at that time unable to concur in the report. Dr. Peterson stated his primary interest lies in obtaining additional review of Dr. Bird's contentions and this will require that those contentions be formalized in a report that can then be subjected to an external peer review process and he remarked the proposed revision encourages Dr. Bird to develop such a report and addresses the DCISC convening a review panel with independent experts, but in the interim period the Committee's current evaluation with respect to the seismic adequacy of the plant would not change. The Committee members and consultants then engaged in discussion of the revised conclusion of the Fact Finding Report including the subject of peer review, the current documentation on file from Dr. Bird and the needs for a report that is suitable for peer review by other agencies including PG&E and the IPRP.

Dr. Budnitz expressed his view that obtaining additional peer review of Dr. Bird's contentions would be beneficial, but that review should not be sponsored by the Committee rather it should take place in the normal way, that is, by Dr. Bird submitting an article to professional journals. Dr. Meshkati observed that Dr. Bird has addressed a report to the DCISC and he commented he does not believe the DCISC has expertise in neotectonics, which he described as a very narrow geological discipline, to be in a position to review Dr. Bird's contentions and Dr. Meshkati stated he is a follower of the proposition of deferral to the experts. Dr. Budnitz also questioned the use of the term peer review in this effort.

            During the discussion of the August 17-September 24-25, 2024 Fact Finding Report conclusion concerning seismic issues PG&E's Dr. Chris Madugo commented the Technical Integration and the Participatory Peer Review teams review of what is now available concerning Dr. Bird's contentions and he commented there is not a lot of backing to date to support his contentions. Dr. Madugo remarked Dr. Bird needs to provide evidence to counter the evidence that PG&E has produced in the 2024 Updated Seismic Assessment and otherwise. Dr. Madugo stated he believes a peer review might be performed on the documentation that has already been provided by Dr. Bird.

            Dr. Seitz, of the California Geological Survey and a member of the IPRP commented the IPRP has not yet looked at Dr. Bird's data in detail and he suggested that the reference to a report that can be subjected to peer review should be to a report "suited for independent review." Dr. Seitz, in response to Dr. Kadak's query, replied the IPRP has not made a decision on when it will review Dr. Bird's contentions and the IPRP was waiting for the NRC reaction, but given that the NRC has taken up the matter the IPRP's review may be coming sooner and he stated he would be discussing these matters with his fellow IPRP members. Dr. Seitz observed peer review is a part of the SSHAC process and there is a precedent for peer review outside of the literature and he believes a subject matter expert familiar with nuclear hazard risk assessment and source characterization, besides neotectonics, be engaged to ensure familiarity with source characterization, defining slip rates, and hazard modeling.

            Ms. Sherry Lewis of Mothers for Peace was recognized and Ms. Lewis asked that the Committee's review be of a full report by Dr. Bird and not limited to what Dr. Bird has provided to date which has been characterized as not sufficiently complete. She further stated she questions Dr. Budnitz' objectivity.

            PG&E Senior Director Mr. Tom Jones was recognized and Mr. Jones stated PG&E would respond to what the Committee asks of it in context of the Long Term Seismic Program and PG&E will not be amending the 2024 Updated Seismic Assessment, the report completed for SB 846, and he characterized PG&E's involvement as increasing ongoing scope and therefore the Long Term Seismic Program is the proper venue for PG&E's consideration.

            The members of the DCISC then engaged in a dialogue concerning the details of the final wording of the conclusion and the recommendation to be included in Section 3.1 of the August 27-September 24-25, 2024 Fact Finding Report, and after a spirited and detailed discussion the following wording was read into the record for Section 3.1:

"Conclusion: The discussion with PG&E experts during this Fact-Finding meeting provided valuable additional information and clarifications that has substantially aided the DCISC in performing its own evaluation of the positions, claims, and conclusions of Dr. Peter Bird concerning the seismic hazard at the DCPP site. Further review of Dr. Bird's concerns is warranted but will require Dr. Bird to document them in the form of a report that is suitable for an independent peer review. Based upon the review performed during this Fact-Finding, the DCISC does not have a basis to alter our previous conclusions about the adequacy of seismic safety at DCPP. Nevertheless, we encourage Dr. Bird to develop a report that can be subjected to independent peer review by independent subject matter experts. It is premature
for the DCISC to reach any definitive conclusions about Dr. Bird's concerns or to change our current assessment that DCPP has appropriate and adequate seismic safety, until after this independent review information is available. That is, the DCISC's ultimate evaluation of the technical issues raised and any conclusions arising from it will necessarily need to await the further work now under way, including by the NRC staff, the IPRP, PG&E and (to be convened) Neotectonics subject matter experts.
 
Recommendation for DCISC: The DCISC should convene one or more experts with expertise in Neotectonics to further evaluate Dr. Bird's concerns."

            On a motion made by Dr. Peterson, seconded by Dr. Meshkati, the August 27-September 24-25, 2024 Fact Finding Report was unanimously approved and its transmittal to PG&E authorized.

            A short break followed.

XXIII  INFORMATION ITEM PRESENTED BY THE NUCLEAR REGULATORY COMMISSION SENIOR RESIDENT INSPECTOR FOR DCPP

            The Chair requested Consultant McWhorter to introduce the NRC's Senior Resident Inspector for DCPP Mr. Mahdi Hayes. Mr. McWhorter welcomed Mr. Hayes to these proceedings and reported Mr. Hayes is a graduate of Texas A & M University and holds a Bachelor of Science Degree in Nuclear Engineering. He stated Mr. Hayes previously worked for Knolls Atomic Power Laboratory prior to joining the NRC in 2006, after which Mr. Hayes served as the Resident Inspector at the Columbia Nuclear Generating Station in Washington and then as an Operations Engineer and Operations Licensing Examiner in the NRC's Region IV offices in Arlington, Texas after which in 2022 he was assigned as the Senior Resident Inspector for DCPP.

Presentation by the NRC Senior Resident Inspector for DCPP Mr. Mahdi Hayes on the NRC's Annual Assessment of DCPP's End-of-Cycle Performance during Calendar Year 2023.

            Mr. Hayes began his presentation by introducing Mr. Eli Garcia, the Resident Inspector for DCPP and he reported Mr. Garcia began that assignment in September 2024. He also introduced Ms. Amy Elam who is the site administrator in the Region IV office for Diablo Canyon and two other power plants.

            Mr. Hayes reviewed the mission statement for the NRC as follows "NRC licenses and regulates the Nation's civilian use of radioactive materials to provide reasonable assurance of adequate protection of public health and safety and to promote the common defense and security and to protect the environment." He reported the NRC consists of five commissioners nominated by the President and confirmed by the U.S. Senate and the President selects the NRC Chair. He reported the NRC Executive Director of Operations is responsible for the agency's daily operations. The NRC consists of four regions with Region I headquartered in King of Prussia, Pennsylvania, Region II in Atlanta, Georgia, Region III in Chicago, Illinois, and Region IV in Arlington, Texas. Mr. Hayes reported Region IV is the largest in terms of area but it has the lowest number of reactor sites.

            Mr. Hayes asked Resident Inspector Mr. Garcia to review his background. Mr. Garcia reported he holds a Bachelor of Science Degree in Nuclear Engineering from Texas A & M University and he stated he received his training in the Resident Inspector Development Program and was assigned to a rotational assignment at the Hope Creek Nuclear Generating Station in New Jersey and then served as permanent Resident Inspector for two years at the Salem Nuclear Generating Station in New Jersey. Dr. Peterson welcomed Mr. Garcia and remarked the DCISC Members meet frequently with the resident inspection team during fact finding.

            Mr. Hayes reviewed the role of the Resident Inspectors which he described as regulation verification through the conduct of in-depth baseline inspections. He stated all plants get a minimum number of inspections and the resident inspectors facilitate communication and act as the eyes and ears of the NRC by providing operational awareness and detailed facility knowledge, emergency response, and act as the first NRC responders to provide prompt information and an independent assessment concerning any decision making. Dr. Peterson remarked there was discussion earlier about the safety significance of findings, activities of low safety significance, and the self-reported versus self-revealing nature of these activities. In this context Consultant McWhorter commented on the untimely declaration of inoperability of the ventilation fan being designated as Non Cited Violation and considered to be of low safety significance. Mr. Hayes stated performance deficiencies are screened through the enforcement and safety significance determination processes to see if standards apply. He remarked the ventilation fan did not work and accordingly it was assessed for operability to perform its function. A designation is then assigned as a performance deficiency and a determination made as to a regulatory aspect under 10 CFR (Title 10 Code of Federal Regulations which comprises the NRC's safety regulations). Mr. Hayes stated the NRC has a quality assurance program with sixteen different criteria, one of which is corrective actions, and for the ventilation fan issue there was an operability determination procedure that required a declaration of its inoperability at the earliest opportunity in order that prompt correction action can be taken. This was under 10 CFR Part 50 Appendix B, Criterion 5 for the safety-related ventilation fan and he stated once you have a regulatory requirement an enforcement action, a violation can be assigned. Accordingly it was designated as being of low safety significance and was entered into the plant's Corrective Action Program which meant that, unlike for a cited violation, the licensee does not need to review the prospective corrective action with the NRC. He reported the NRC resident inspection team will then get the opportunity to inspect the issue and the final cause determination and corrective action. In response to Consultant McWhorter's request Mr. Hayes identified a previous issue with a condenser being in a condition unable to receive steam and therefore no longer meeting the requirement of the licensing basis for allowing the plant to not go offline at a certain power level and he commented the assigned violation indicates that there was a tie between condenser available and "P9." He reported there is an associated permissive aspect and the licensee is allowed not to take the plant offline in the event of an offsite power rejection. He reported this was designated as a Green issue because the plant was at a high power level and it did not affect the licensing basis.

            Mr. Hayes reported inspection activities employ a baseline inspection program at each

site to review everything from operability determinations for systems and how systems are aligned to fire protection systems and these inspections look at a cross-section of licensee's activities and are focused on items that are in the Technical Specifications or are safety related.

            Mr. Hayes reported for the 2023 Annual Assessment, the NRC determined PG&E operated the plant safely and in a manner that preserved the public health and safety and protected the environment. DCPP was in the Column 1 of the Licensee Response Column with all Performance Indicators and Performance Deficiencies in Green status and for 2023 there were nine Green Non-Cited Violations (NCVs) and one Green Finding issued. Accordingly in 2024 Mr. Hayes reported the NRC will conduct baselines inspections.

            In response to Dr. Meshkati's request Mr. Hayes explained that a Licensee Event Report (LER) is triggered when there exists a regulatory requirement under 10 CFR 50.72 or 50.73 and under the guidance provided by NUREG[26] 1022. He reported in 2022 DCPP initiated a LER for a reactor trip. Mr. Hayes commented the requirements for submitting an LER have been in existence for a long time, well before the advent of the systematic compilation of operating experience.

            Mr. Hayes reported on DCPP inspection activities during 2023 when the NRC completed approximately 1,500 hours of direct inspection out of approximately 2,000 total inspection hours including resident inspection baseline inspections, regional team inspections, emergency preparedness inspection, in-service inspection, radiation safety inspections, Security inspections, commercial grade dedication, licensed operator requalification inspections and license renewal activities were also conducted in 2023. He reported three NRC commissioners visited DCPP during 2023. Mr. Hayes stated inspection reports are produced quarterly and are made publicly available.

            Mr. Hayes then provided his overview of the regulatory process which includes Cornerstones representing the inspection areas. He reported the resident inspectors deal primarily with initiating event, mitigating systems, barrier integrity, and emergency preparedness. Mr. Hayes reported specialist inspectors from Region IV address radiation safety and security inspections. He reported the Cornerstones feed into the risk-informed baseline inspection procedures and those are in turn fed up into the significance determinations and to the Performance Indicator thresholds. The assessment process then continues to the NRC's Action Matrix. Mr. Hayes reported the NRC holds an annual meeting to discuss plant performance and is doing that today with his presentation.

            Mr. Hayes stated the Action Matrix includes making a determination as to whether anything additional is required and that determination is driven by the color significance of the findings and the Performance Indicators that have been issued over the prior calendar year. He reported DCPP remains in Column 1 with all Performance Indicators in Green status.

            In response to Consultant Kadak's query, Mr. Hayes explained the risk-informed baseline inspections are determined due to an inability to review everything at the site and to concentrate on what is addressed in the Technical Specifications and modeled in the PRA. Mr. Hayes commented not every system is necessary for the safe operation of the plant and if there are challenges with any of the equipment that is in the Technical Specification that are of high risk significance, those are the items the NRC inspection activities will focus on. He then described the color bands used for the Acton Matrix:

GREEN (Licensee Response Band )
• Cornerstone objectives fully met. Nominal risk with nominal deviation from expected performance.

WHITE (Increased Regulatory Response Band)
• Cornerstone objectives met with minimal reduction in safety margin. Changes in performance consistent with Δ[27]CDF[28]<10-5 (ΔLERF[29]<10-6).

• YELLOW (Required Regulatory Response Band )
• Cornerstone objectives met with significant reduction in safety margin. Changes in performance consistent with ΔCDF<10-4 (ΔLERF<10-5).

• RED (Extensive Regulatory Response Band )
• Performance within the cornerstone represents an unacceptable loss of safety margin. Changes in performance consistent with ΔCDF>10-4 (ΔLERF >10-5). Sufficient safety margin still exists to prevent undue risk to public health and safety.

Mr. Hayes reported Column 1 indicates all Green Performance Indicators and for findings, if higher risk issues are documented in inspection reports, licensees are moved to different columns. For instance he commented two White designations in any strategic performance area move a plant into Column 2 and this can progress all the way to Colum 4 for unacceptable performance. Mr. Hayes commented the NRC regulates by unit and for two unit plants each unit can be in a different response column. He reported one site in the U.S. is now in a degraded performance category and nine are in the regulatory response category.          

             Mr. Hayes stated the NRC places a high priority on publicly available information and on keeping the public and stakeholders informed of its activities. He reported at www.nrc.gov, one can find site specific oversight information, public meeting dates and transcripts, read NRC testimony, speeches, press releases, and policy decisions; and access the agency's Electronic Reading Room to find NRC publications and documents. He provided the following for use in contacting the NRC: to report an emergency (301) 816-5100 (collect calls accepted), report a safety concern (800) 695-7403, allegation@nrc.gov. General information or questions www.nrc.gov, select "What We Do" for Public Affairs. Mr. Hayes provided forms for the public to use to provide feedback on this NRC public meeting.

            In response to Dr. Meshkati's query as to whether the resident inspectors are exposed to the Human Factor Analyses and Classifications (HFAC) that the plant's Human Performance organization produces routinely Mr. Hayes stated this is not something he is familiar with and he remarked markers are identified that cut across any site and these are applied to any finding or non-cited violation to assess contributors to the finding or NCV. In response to Mr. McWhorter's observation relative to the ventilation fan matter Mr. Hayes stated the Crosscutting aspect for that event was training, that is, human performance and should another event with this aspect be identified, two violations would trigger a change from Green to White status. Mr. McWhorter described this as tracking across issues for similarities. In response to Dr. Meshkati's follow up inquiry Mr. Hayes stated the resident inspection team would not typically need to review the results of the HFAC reviews. Dr. Budnitz commented the NRC has a Research Office that has a group of human factors experts and this group follows research on human factors in other safety areas around the world. He reported there is another group in the Office of Nuclear Reactor Regulation who follow human performance to assure the manner of NRC regulations takes advantage of the latest knowledge. Dr. Budnitz reported these teams provide their additional insights to the resident inspectors at the individual plants and he remarked it is not common that the on-site resident inspectors would follow human performance issues on this level, but when something is ripe for implementation by all the inspectors it becomes part of their tools and the NRC expert teams are available to assist the resident inspectors as needed. Dr. Meshkati reported the HFAC method was developed for the FAA for use in the aviation industry but it is now being migrated to the nuclear industry and he described this as a treasure trove of data with respect to human performance. Dr. Meshkati commented he believes it would be very useful because of the human performance issues the resident inspector are exposed to for them to have access to site specific HFAC applications. Mr. Hayes stated he now better understood Dr. Meshkati's question and he stated if anything occurs at the site that has a human performance aspect the resident inspectors are able review the issue and would make a determination if it rose to the level of documentation. If so it would be documented in an inspection report and be followed up during a future inspection to determine if the corrective actions were implemented. But he commented for a human factors analysis the resident inspectors would see if there was a change to the site and review that change, but would not necessarily inspect or look at the report that implemented the change and he gave the example of the Control Room, which he described as a human factors area, which has been through a process and a program and he stated the resident inspectors look at the final results.

            Dr. Budnitz observed prior to the accident at the Three Mile Island Nuclear Generating Station in Pennsylvania in 1979, the NRC had not paid much attention to human factors and this was understood after the accident to have been a mistake. Dr. Budnitz reported he led the NRC investigation into the accident at Three Mile Island as the Technical Coordinator and as a major finding of the investigation immediately afterward the NRC established a human factors branch in the Office of Nuclear Regulatory Research, for which Dr. Budnitz then served as the Director, and a comparable office was also established in the Office of Nuclear Reactor Regulation. He commented this was propagated to the industry through the efforts of the Electric Power Research Institute and INPO which was founded several years later. Dr. Budnitz observed it is important not to take human factors for granted as this remains one of the key areas where safety compromises can arise.

            In response to Consultant Kadak's request Mr. Hayes described a typical day for a resident inspector as beginning with their attendance at the site's morning meeting for the daily plan, to then see if any issues have developed overnight, and then to review corrective action documents written in the last 24 hours. Following would typically be looking for opportunities to observe work planned in advance for that day which the inspection team previously planned to observe. Mr. Hayes reported the inspectors generally also attend the end of the day plan meeting and they walk down the Control Room on a daily basis. In response to Consultant Kadak's question Mr. Hayes stated the inspectors sometimes attend the Corrective Action Program meetings if there is something to be addressed that is of particular interest and in response to Dr. Kadak's query he stated there is no particular aspect of DCPP that he finds to be more concerning than at the other plants Mr. Hayes has visited.

            In response to Dr. Meshkati's question Mr. Hayes reported that the time a resident inspector is assigned by the NRC to a particular site is generally limited to seven years and the average time is from four to five years. He remarked this limit is not as rigidly enforced as it was previously.

            Dr. Peterson thanked Mr. Hayes for his presentation and again welcomed his colleagues and Dr. Peterson extended a standing invitation to the NRC to attend meetings of the DCISC in the future as this is very useful and it complements the frequent meetings the DCISC fact finding teams have with the NRC resident inspectors at DCPP.

            Senior Director Tom Jones was recognized. Mr. Jones reported PG&E completed an updated re-analysis of tsunami hazard wave height including storm surge and sea level rise projections. This work was completed in July 2024 and was communicated on August 16, 2024 to the California Coastal Commission and Mr. Jones stated it will be sent directly to Dr. Johnson and to Dr Seitz and directly to the IPRP and to the DCISC. He described the work as quite extensive and done at the request of the Coastal Commission for the Coastal Zone Management Act process as part of the License Renewal process. Dr. Peterson stated a Committee review of this report should be scheduled for a future fact finding.

 XXIV ADJOURN MORNING MEETING            

            The Chair adjourned the morning meeting of the DCISC at 12:10 p.m.

XXV   RECONVENE FOR AFTERNOON MEETING

            The afternoon meeting of the DCISC was convened by the Chair at 1:30 p.m. Dr. Peterson welcomed those present and asked for comments from his fellow members.

XXVI  COMMITTEE MEMBER COMMENTS

            There were no comments by any member at this time.

XXVII PUBLIC COMMENTS AND COMMUNICATIONS

            Dr. Justin Cochran, participating remotely, was recognized. Dr. Cochran is the Senior Nuclear Advisor for the California Energy Commission and stated he has attended and enjoyed the sessions of this public meeting over the last two days. He thanked the DCISC for the work it performs and stated the Energy Commission values the information that comes from the DCISC's work and its reports in public meetings. He also recognized and thanked Dr. Meshkati for serving on the DCISC, succeeding former DCISC Member Dr. Peter Lam who served with distinction for many years. Dr. Cochran stated he also wanted to recognize and thank the PG&E team for their work in supporting the DCISC as well as the AGP audio visual team. Dr. Cochran stated he wanted to acknowledge that these public meetings are important and promote the sharing of information and they create a forum for the community and the local entities to express their views and concerns as has been evident in the last sessions. He observed the DCISC supports an independent environment in which complex and technical discussions can be held and debated in a public forum which is extremely important. He stated few people recognize how rare and unique these opportunities are across the nuclear sector in the rest of the United States. Dr. Cochran closed his remarks with the observation this has been a very informative two-day session both for the discussion and the presentations which have been extremely valuable.          

            Mr. Bruce Severance was recognized. Mr. Severance said he has just read a public comment on the Diablo Canyon Decommissioning Engagement Panel's website that he believes could be interpreted as a terrorist threat. He commented failure modes of terrorist attacks are not discussed in a public forum, but he stated his belief it is important for DCISC staff to consider the possibility of attacks by terrorist and security measures. He commented there was recently video footage of a security staff member who was asleep on the job.

XXVIII INFORMATION ITEMS BEFORE THE COMMITTEE (Cont'd.)

            Senior Director Jones introduced Mr. Chris Newport to make the next informational presentation and reported Mr. Newport is the Acting Director for the Quality Verification Program and in that role has responsibility for oversight of audits, assessment, plant quality control, quality control inspections and inspection of received materials as well as for compliance with the requirements of 10 CFR quality assurance programs. He reported Mr. Newport has more than 29 years regulatory experience within the nuclear energy production industry following a career in the U.S. Navy submarine service. Mr. Newport has held roles in regulatory compliance at plants across the U.S. and in the DCPP Operations Department. Mr. Newport holds a Bachelor's Degree in Control System Engineering from the U.S. Naval Academy and a Master's Degree in Engineering Management from Catholic University.                                   

Quality Verification Organization's Perspective on Plant Performance, Top Issues, and Recent Quality Performance Assessment Reports.

            Mr. Newport reported he began his assignment as Acting Director of the Quality Verification one day ago. He stated as required by federal regulation the Quality Verification Department acts as an independent group within DCPP and he reported its functions break down into two areas he termed Quality Verification (QV)and Quality Control (QC). Departmental responsibilities include audits, assessments, independent in-plant inspections which Mr. Newport reported consist of QV functions and plant QC inspections include vendor/supplier audits and material receipt inspections. Mr. Newport stated there is an industry process wherein the vendors supplying materials to nuclear operators are audited such that when parts are received from these vendors they can be certified as acceptable for use in a nuclear context. He explained destructive testing is also done by DCPP at local laboratories which is not unlike the practices followed in the aviation and other industries for critical components.

            Mr. Newport reported in his role he reports directly to the Chief Nuclear Officer and this is to maintain the Quality Verification organization as an independent entity. Dr. Meshkati remarked the concept of an independent role in an organizational hierarchy was raised in the deliberations of the Federal Aviation Administration (FAA) Expert Panel on which Dr. Meshkati participated which was convened to investigate incidents with the Boeing Company in context of the organizational designation authorization (ODA) whereby Boeing employees were delegated to perform independent inspections and Dr. Meshkati remarked the panel's review found this system is very delicate. In response to Dr. Meshkati's question Mr. Newport replied his performance appraisal job review is conducted by the Chief Nuclear Officer and he reported persons rotate in an out of the QV Director assignment for various durations. Dr. Meshkati commended the FAA Expert Panel's Report to Mr. Newport for review as there were numerous issues with respect to the notion of independence explored in that report and PG&E may learn something from the panel's work. Mr. Newport thanked Dr. Meshkati and commented the nuclear industry is arguably the strongest in the use of organizational safety culture aspects through the employment of a Corrective Action Program, the employee concerns process, and the presence of the federal regulators available to receive allegations and he stated emphasis is placed on the ability to always be able to raise safety concerns without fear of retaliation which he reported is illegal under federal law and which in the past has resulted in prosecution by the NRC. Mr. Newport commented besides the QV Department oversight at DCPP also includes other organizations including the Nuclear Safety Oversight Committee (NSOC), the Independent Safety Committee (DCISC) and the NRC.

            In summarizing performance by DCPP, Mr. Newport reported that DCPP continues to exhibit traits reflecting a strong nuclear safety culture. Recent comprehensive assessments by WANO and INPO as well as by the NSOC confirm DCPP continues to effectively implement the Quality Assurance Program consistent with regulatory requirements and its commitments to the NRC. He reported QV has two primary responsibilities including ensuring identification of gaps to compliance as well as closing gaps to excellence. Mr. Newport commented the station focuses on low level issues to prevent more significant issues from emerging and he remarked this philosophy permeates through the nuclear industry thanks for the influence of U.S. Navy Admiral Hyman Rickover, recognized as the father of the U.S. nuclear Navy. Mr. Newport reported DCPP regularly receives the highest industry ratings, but he remarked that does not mean there are no areas for improvement. He reported given the decision to operate to 2030, the station is focused on proficiency after having hired a significant number of new employees over the last 1-2 years in various departments as well as on succession and diversity in experience. He commented DCPP is fortunate to be able to draw upon Cal Poly graduates as well as on experienced engineers from outside the nuclear industry but he stated newly hired individuals need to learn how things are done at DCPP and in the nuclear industry.

            Mr. Newport described and discussed performance summaries for various DCPP organizations as follows:

→        Operations - is focusing on plant status control, including the clearance and tagging process for out of service equipment and station equipment alignment. He reported there have been some near misses which did not result in consequences, but left uncorrected consequences could result. He reported these issues were identified by DCPP's peers in INPO and QV personnel conduct observations in the plant to ensure the corrective actions put into place are effective.

→        Maintenance - is focusing on effectiveness and efficacy of corrective actions in response to lower-level performance challenges including on training and communication concerning corrective actions. In response to a query, Mr. Newport stated the QV organization does not have responsibility for the Corrective Action Program and that responsibility lies with the Performance Improvement organization and he described the Corrective Action Program as a robust program which recently underwent an NRC three-week inspection.

→        Emergency Planning - is focusing on drill & exercise performance including communications with San Luis Obispo County where there have been a few low level problems in recent exercises and on successful and efficient implementation of the Emergency Response organization (ERO) staffing plan.

→        Projects - is focusing on ensuring DCPP processes are effectively integrated across the entire organization and on the replacement of the rod control indication system with a digital system. Mr. Newport commented projects are proceeding at a much faster pace and the Projects organization has brought in a number of new people to assist and is focused on integrating these employees with the processes already in place. He reported subject matter experts from other organizations are providing valuable input to the Projects organization.

→        Engineering - is focused on enhancing plant equipment reliability across the plant, particularly secondary-side equipment and its replacement at the right periodicity to ensure sustained excellence in plant operation. Mr. Newport commented DCPP has not experienced many issues or transients as a result of secondary system equipment when compared to the industry. He reported there is an effort at DCPP to risk-inform and target the most important secondary plant equipment to get it replaced or maintained.

→        Work Management/Outage Management - is focused on the support of outage management milestones as DCPP transitions from two larger scope outages necessary for continued operations to traditional scope outages with tight schedules.

            Mr. Newport concluded his presentation with the observation that overall plant performance remains strong and is on a stable trajectory. QV and the site are focused on sustaining that excellence and the QV organization will continue to assess and challenge the station's performance independently and report out to individual departments, the CNO, the NSOC and to the DCISC. In response to Dr. Meshkati's question Mr. Newport confirmed the QV organization follows up on the resolution of its inspection recommendations, which are referred to as findings, and he stated if a finding is not corrected within 120 days a Yellow classification is triggered which gets visibility from the DCPP leadership team. He remarked that a visual management tool is now used on a monthly basis which employs color-coded designations to permit all employees in the plant to see the QV's information on organizational trajectories and this is a part of the LEAN Management System employed at DCPP and throughout PG&E.

            In response to a query from Consultant McWhorter Mr. Newport reported the last biannual external industry organizational review was conducted and no significant issues were identified. He stated he would need to provide information on when the next such review is scheduled. In response to Dr. Meshkati's inquiry as to interference in the QV organization's independence through pressure for scheduling or financial reasons Mr. Newport reported the QV organization does not experience influence from those types of issues and if QV identified those issues as having affected other organizations in the plant he has a direct reporting obligation to the Chief Nuclear Officer to identify and raise those issues for correction and if he were to receive pushback from other directors he commented those individuals would be strongly coached by multiple levels within the DCPP organization. In response to Consultant Wardell's inquiry Mr. Newport confirmed QV continues to issue annually a Quality Performance Assessment Report (QPAR) and the latest document is from 2023 and the information he provided today was based on that report. He reported the QV organization no longer maintains a Top Ten List as that has been replaced by the color-coded visual management tool he described. In response to Consultant Kadak's query Mr. Newport reported the QV organization consists of 23 employees and other personnel are brought in from time to time from other departments on a rotational basis and he remarked this has proven valuable. In response to Consultant Kadak's question Mr. Newport reported the Performance Improvement organization tracks human performance error by department while QV also has input metrics that track human error. He reported QV does not conduct equipment receipt inspections for embedded computer codes, etc., as that responsibility falls to the Cybersecurity organization which has an entire program for cybersecurity issues. Mr. Newport observed DCPP does not employ a great deal of what he described as cutting edge digital technology in the plant and this assists in limiting cybersecurity vulnerabilities.

            Mr. David Weisman of the Alliance for Nuclear Responsibility was recognized. In response to Mr. Weisman's inquiry as to what proportion of the secondary side equipment described by Mr. Newport is safety-related and of that equipment how many of the upgrades that are needed to secondary side equipment were on the PMO++ List [a part of the Preventative Maintenance Optimization ++[30] Program]. Mr. Newport replied that secondary plant equipment is not safety related, but some failures can cause a transient[31] resulting in a power reduction or even a turbine or reactor trip which is never good. He stated this is a concern with the secondary equipment and all of the secondary equipment was considered as part of the PMO++ List. Mr. Newport observed it takes time to replace equipment and DCPP is specifically targeting secondary side equipment that presents a single point vulnerability that could lead to a transient and ensuring that all such equipment is either adequately maintained or replaced. He reported DCPP has not seen issues with safety-related equipment and is focused on the appropriate application of its resources.

            Mr. Bruce Severance was recognized. Mr. Severance stated in his conversation with PG&E staff he has been impressed by their commitment to continuous improvement and excellence. He commented his focus is on embrittlement and pressurized thermal shock. He stated he is aware there are redundant systems for tracking a loss of coolant accident (LOCA) and he questioned the approach of what he described as the "leak before you break" theory and strategy and he stated in 2000 a number of cross members were removed from primary and secondary coolant system piping. He stated he was puzzled by the theory's proposition that a small leak that is detectable is better than a catastrophic break and he asked if it is still a governing programmatic rule. He commented he feels such a theory might make sense early in the plant's life but stress corrosion cracking and other forms of corrosion can cause degradation to pipe and over time a design basis accident could produce a far greater LOCA. Mr. Newport responded and stated Mr. Severance was describing a LOCA on the primary system and he reported the primary system leak rate is tracked daily and the Technical Specification limit is one gallon per minute and if that limit is exceeded the plant must immediately be shut down. Mr. Newport further reported the primary system piping is rigorously, frequently, and intensively inspected including the welds and joints and essentially no leakage is tolerated. He reported the plant is designed so that if a design basis accident involving a large break LOCA occurs the plant can be safety shutdown and prevent a release of radioactivity. Dr. Budnitz explained that the designers of the plant, the NRC, and industry regulations require extra redundancy to provide extra margin and there are some systems for which when you lose one of them you must shut down but for others that is not necessary. Over time industry programs and the NRC regulations allow taking one system offline to do maintenance while the plant continues to run because data and analysis demonstrates the remaining functional systems are adequate to maintaining a sound safety margin for the given situation. He observed online maintenance is always preferred because shutting down produces stress and transients are undesirable. Mr. Severance thanked Dr. Budnitz and commented his explanation made sense to him.

            Mr. Severance remarked that he has read in reports on pressurized thermal shock that a 25°F. per hour reduction in temperature when engaging in shutdown and he asked if you have a severe break he understood that failure mode analysis does not address multiple pipe breaks at the same time in the primary system as it is considered not probable and he inquired how many gallons per hour can a plant lose until the Emergency Core Cooling System (ECCS) introduced cold water into the reactor core. Dr. Peterson replied this is referred to as a large break coolant accident and the hypothetical limiting case is a double guillotine break on a cold leg, at which point the reactor will depressurize rapidly and all of that accident scenario has been analyzed and the ECCS can provide sufficient cooling to maintain fuel temperatures below any type of failure limit for that specific accident. Mr. Newport observed cool down rates are predicated on a reactor operating for 20 more years, but in a large break LOCA they will be exceeded as water is injected and the reactor cools rapidly in excess of the cool down rate but afterward the unit will not be operated again. Dr. Budnitz observed there are procedures, standards and methodologies used throughout the industry and a part of what the QV organization does is to provide additional checks and a level of assurance that these procedures, standards and methodologies are being followed.

            Senior Director Mr. Tom Jones introduced the next presentation. Mr. Jones introduced DCPP Nuclear Fuel and Decommissioning Director Mr. Al Bates to make that presentation. Mr. Jones reported Mr. Bates rejoined the DCPP leadership team in 2023 after having previously served as Director of Engineering at DCPP. Mr. Jones reported Mr. Bates has responsibilities for fuel procurement for extended operation, spent fuel storage, and decommissioning planning and for engineering and budgeting for those activities . Prior to his return to DCPP Mr. Bates was Senior Manager of Regulatory Affairs and Technical Advisor to the Chief Nuclear Officer for Southern California Edison Company and was a primary participant in the decommissioning oversight of the San Onofre Nuclear Generating Station (SONGS). Mr. Jones reported Mr. Bates has 45 years of experience in the nuclear industry including as a project manager and has worked to advocate for digital control integration and the use of robotics at nuclear facilities. Mr. Bates holds a Bachelor of Science Degree in Nuclear Engineering from Purdue University and previously held a Senior Reactor Operator License at DCPP.

Update on Recent Campaign to Move Spent Fuel Assemblies from the Spent Fuel Pool to the Independent Spent Fuel Storage Installation.

            Mr. Bates began his presentation by displaying a photo of the site of the Independent Spent Fuel Storage Installation (ISFSI) which is located above and behind the plant and he reported the ISFSI is sized to store all fuel through the end of the DCPP current operating licenses, with an additional 20 years' worth of continued operation spent fuel storage available in each of the two spent fuel pools. He observed from that perspective DCPP has sufficient storage capacity available. Mr. Bates reported DCPP has now safely completed seven loading campaigns since 2009 and is currently conducting Campaign No. 8 which provides for the storage of 12 multi-purpose canisters (MPCs) with each containing 32 fuel assemblies.

            Mr. Bates described the scope of Campaign No. 8 as including the transfer of 192 spent fuel assemblies from each spent fuel pool to dry storage. This will require loading 12 canisters, 6 from each unit at the rate of one canister per week with crews working six days a week during the period from July 22 to October 18, 2024. He reported to date Campaign No. 8 has been going very well.

            Mr. Bates reported safe and successful execution of a loading campaign requires robust procedures to govern all work activities and PG&E management oversight of all work activities. He stated PG&E's contract partners (the Holtec and Bragg firms) have provided experienced crews. The Holtec firm has provided the canisters and the Bragg firm performs the heavy lifting. Mr. Bates reported Holtec and Bragg also provide technical support for loading, for seal welding and for transporting the canisters. He reported the crews remain essentially intact and the personnel are used throughout the campaign and this has also been true for the vendors. Reviews to ensure radiation dose levels for workers have been kept as low as possible have continued and this has required adjustments along the way to achieve lower dose.

            Mr. Bates displayed and described several photos. The first was of the process of loading a fuel assembly, each assembly is approximately 12 feet long, from a spent fuel pool into a Holtec MPC and he remarked that the fuel in the pool is covered by 22 feet of water. A second photo shows the installation of the MPC lid after loading has been completed and the removal of the loaded Holtec HI-TRAC transfer cask from the spent fuel pool. He reported the cask lid is 9 inches thick and provides substantial radiation shielding once the MPC comes out of the water.

            The next photo Mr. Bates displayed and described showed the loaded transfer cask in the cask washdown area and within its seismic restraint as the lid was being seal welded in place and the bulk water removed through a forced helium dehydration backfill process which Mr. Bates stated eliminates corrosion within the MPC. He reported the seal welding of the closure ring is performed with a robotic welder and the ports used for the helium dehydration process are also welded shut upon completion of that process. He reported the welds have a 100% dye penetration examination immediately after they are in place. Dr. Peterson remarked that often radiographic inspection is required for welds and Mr. Bates responded the MPCs are designed and licensed for the dye penetration inspection and this is common across the industry and it pertains to the nature of the seal welds. He responded to Dr. Peterson comment that the MPC lid has a structural function and the lid is placed into a recess in the MPC designed to accommodate the lid.

            Mr. Bates next photo showed the removal of a HI-TRAC cask from the Cask Transfer Facility and reported the HI-TRAC casks are transported using the Vertical Cask Transporter which travels slowly over a period of two hours from the plant to the ISFSI. He explained the MPC is lifted a very small amount to take the weight off the bottom and the lower drawer shielded panel is then removed to allow the MPC to then be lowered into the HI-STORM storage cask below. A lid is installed and the HI-STORM cask with the MPC inside is then lifted from the Cast Transfer Facility. He commented radiation shielding is always in place to ensure worker safety. Mr. Bates commented the incident that happened at the San Onofre Nuclear Generating Station involving a storage cask occurred on a different system which had much different clearances than the system in use at DCPP.

            Mr. Bates next photo showed the installation and anchoring of the loaded HI-STORM canister on the ISFSI pad. He reported the HI-STORM cask uses passive cooling ports with cold air entering from the bottom and warm air exiting from the top.

            Mr. Bates reported on the current status of spent fuel with the 2024 Campaign No. 8 which is still underway adding 12 casks containing 384 used fuel assemblies. Mr. Bates commented that the crew's focus since reaching the halfway point in the campaign has been on avoiding complacency, on the use of human performance tools, and on procedural compliance. He reported there are two more casks to be loaded to complete Campaign No. 8. At the end of this campaign, the ISFSI will contain a total of 70 casks with 2240 used fuel assemblies. He reported as of today the ISFSI pad contains 68 storage casks with 2,176 used fuel assemblies and this includes 10 casks from current on-going campaign. Mr. Bates reported the work has been performed safely, and without incident or delay and the NRC inspection yielded no violations and provided positive observations particularly on the work briefs by PG&E and its contractors. ALARA (as low as reasonably achievable dose) goals are being met and lessons learned and improvements identified are being captured. He commented relative to ALARA at the commencement of the current campaign the dose received was at the ALARA limits, but with changes made the numbers were driven lower and the ALARA goal was adjusted down during the campaign. He stated he would provide the ALARA data to the Committee.

            In response to a question from Dr Meshkati, Mr. Bates replied the Bragg firm is a commercial crane company and for the spent fuel loading campaigns Bragg handles the crane and heavy rigging work. The Bragg workforce is the smallest contingent, with the Holtec firm being split into two shifts with 12 persons on each shift for the six-day work week with 24-hour per day periods being required to complete the campaign on time. He reported the PG&E workforce consists of four persons on the day shift and two or three on the night shift performing oversight of the contractors but with radiation protection and mechanical maintenance plant staff in attendance there are probably another 30 persons from PG&E involved in the campaign.

            Dr. Meshkati remarked a serious accident in the Phillips Petroleum Company's Houton Chemical Complex in Pasadena, Texas in 1989 was attributed to issues of contractor safety and Dr. Meshkati observed he has been made aware of safety culture issues in connection with the Holtec firm and he queried how PG&E ensures that the PG&E safety culture is being replicated by all the technical personnel. Mr. Bates replied this starts with meetings between PG&E and Holtec leadership prior to commencing a loading campaign to ensure an alignment of standards and that those standards will be carried through with everyone sent to the site. He reported there is oversight of the contractors and he has on his staff a team dedicated to ensuring PG&E's standards are being met. He reported the use of procedural sign-off is intended to validate that quality and efficiency is maintained throughout. In response to Dr. Meshkati's follow up question Mr. Bates replied that structured reports follow a command and control structure and reports are provided to him through a manager and multiple supervisors and the Holtec firm reports to his manager and the manager to Mr. Bates. He commented he is involved with all aspects of the spent fuel loading campaigns and the entire plant staff is kept timely informed of nuclear significant activities and who is in charge. In response to an inquiry Mr. Bates stated that a licensed senior reactor operator is required to be involved with all movement of the fuel within a spent fuel pool, but beyond that point a senior reactor operator is not required on the separate crews. He reported after all fuel is placed in the MPC there are two independent verifications that the correct fuel assemblies from the correct locations were placed in the designated canister, the first is by a senior reactor operator which is done by use of an overhead camera that identifies the fuel assemblies which are marked with large numbers on the top and sides in the spent fuel pool and then secondarily in the canister to verify that every assembly is in its correct location.

            In response to Consultant Kadak's question Mr. Jones reported there are always at least 772 assemblies in each spent fuel pool to allow for a checkerboard pattern and to act as a heat sink when doing a full core offload of the 193 assemblies from a reactor vessel. Mr. Jones stated DCPP operates in a range between 800 and approximately 1,150-1,200 available spaces in its spent fuel pools. Mr. Jones reported loading campaigns are conducted approximately every four to six years and the next campaign is planned for July 2027, after the spring refueling outages and will involve loading 8 to 10 canisters. He reported the operating licenses from the NRC required DCPP to always have space in the spent fuel pools for a full core offload at any time and this includes factoring in new fuel which might be received in anticipation of the next fuel cycle.

            In response to Dr. Meshkati's query, Mr. Bates replied Campaign No. 7 was conducted approximately five and a half years ago and he confirmed Dr. Meshkati's observation that PG&E expects to use many but not all of the same workers from Campaign No. 8 in Campaign No. 9. Dr. Meshkati observed there will therefore be some impact on experiential knowledge by the contract workers and he remarked this is not an issue unique to the nuclear industry and the issue of experiential knowledge in safety is extremely important as is the cohesiveness of the team and the acculturation that the team receives at DCPP. Mr. Bates replied one cannot assume that the company you contracted with last time is the same company on a subsequent assignment and this review starts with review of qualifications and experience. He reported DCPP has the right of refusal for the makeup of the spent fuel loading crews and he observed he would not accept a crew made up of all new individuals and he commented the contractors also do not want a situation where all its employees leave at the same time. He remarked for Campaign No. 8 DCPP had a very well balanced crew in terms of experience levels, all of whom have the proper qualifications and PG&E personnel provide oversight of the entire process including in verifying qualifications and proficiency and dry runs of critical operations are conducted for this purpose before any spent nuclear fuel is handled. Mr. Jones added that PG&E also has the same range of experience and age distribution on its spent fuel teams to ensure a good composition and Mr. Bates confirmed DCPP has an array of personnel with different skills, abilities and experience.

            In response to a question as to provision made for damaged or leaking fuel Mr. Bates responded prior to any fuel being loaded into a canister the age of the fuel is determined which he stated directly affects how many kilowatts the fuel produces and as to the radiation protection to be provided by the canister and the transfer and storage casks. Mr. Bates reported a four-face inspection is conducted of the fuel assemblies and DCPP has an excellent inventory record of fuel failures from operational cycles to identify leaking or damaged fuel and any damaged or leaking fuel is not chosen for placement in a storage canister and he observed the storage of such leaking or damaged fuel will likely be addressed during decommissioning.

            Mr. Jones remarked PG&E has produced some excellent YouTube videos that show the entire movement of the spent fuel and he commended these to the Committee and the members of the public present. Mr. Rathie commented the DCISC's website also includes videos on the topic of the storage of spent of nuclear fuel.   

XXIX  DISCUSSION, DIRECTION AND ACTION, AS APPROPRIATE, BY THE COMMITTEE, CONSULTANTS AND COUNSEL

            Dr. Peterson asked Mr. Rathie to introduce the next topic.

A.        Status of Governmental Agency Interactions, Response to SB 846 Directives, Discussion of Regulatory Matters including R.23-01-007 Phase 2 Issues Including Funding for Extended Operations and Consideration of having Term Limits for DCISC Members, Administrative Matters (including ratification of Amendment No. 4 to Consulting Agreement with Dr. Mark Kirk), Consideration of Approval of New and Revised Committee Policies, Financial Matters, and Other Committee Business.

            Mr. Rathie recognized the presence in the audience of the Deputy Director for Statewide Energy for the Department of Water Resources (DWR) Ms. Delphine Hou and Dr. Deb Luchsinger of Preferred Licensing Services and Mr. Jerry Bischof formerly Senior Vice President of Nuclear Operations with Dominion Energy who are assisting the DWR with its responsibilities in connection with the license renewal for DCPP extended operations. Mr. Rathie reported DCISC representatives have met several times with DWR representatives including during fact-finding. Mr. Rathie reported DWR representatives met with Dr. Meshkati and Mr. Rathie to provide an orientation. Mr. Rathie thanked the DWR representatives for the cooperation they have extended to the DCISC.

            Mr. Rathie reported that last month he and Dr. Budnitz met with five representatives of the California Attorney General including Deputy Attorney General Ms. Megan Hey who has been instrumental in facilitating meetings between the Attorney General's appointee to the DCISC and the Attorney General's staff members. Dr. Budnitz reported during this meeting he responded to questions and briefed the Attorney General's staff on the DCISC's activities and the status of its reviews including its review pursuant to SB 846 of seismic and maintenance issues and concerning other activities in connection with license renewal.

            Mr. Rathie reported that after September 2022 with the adoption of SB 846, the CPUC opened a rulemaking proceeding to implement the statutory provision of the California Government, Public Resources, Public Utilities and Water Codes which were adopted pursuant to SB 846. That proceeding is presently in Phase 2, with Phase 1 having been considered and concluded in two separate Phases with Phase 1 Track 1 dedicated principally to the operation and funding of the DCISC in the period of transition and relicensing. The Phase 1 Track 2 proceeding considered and approved, prior to the end of 2023, moving forward with the extended operation of DCPP and in that phase the findings of the Committee were considered relative to the seismic safety of the site and maintenance which might have been deferred in anticipation of the plant closing. Mr. Rathie then requested his colleague, Mr. Willis Hon a partner with the law firm Nossaman LLP who serves as special counsel to the DCISC for regulatory affairs, to address the Committee concerning the issues pending in Phase 2 that relate directly to the Committee.

            Mr. Hon reported the parties in Phase 2 have submitted comments and proposals on the DCISC's forecast costs and associated activities during DCPP extended operations. Mr. Hon remarked the Committee is not a party to the rulemaking proceeding and has been advised to provide its comments directly to CPUC Energy Division staff. Mr. Hon stated with Mr. Rathie he will be soliciting the members views and direction on the Phase 2 issues he will brief, and the input received can be passed on to the CPUC staff as either the position of the Committee or of any of its individual members.

            Mr. Hon reported the Alliance for Nuclear Responsibility has proposed term limits for DCISC membership which would limit a member's service on the Committee to two three-year terms. The Small Business Utility Advocates has expressed support for the Alliance's proposal while PG&E has not taken a position on the issue. Dr. Budnitz reported that given there was nothing in the docket expressing a contrary view, as an individual and not as a member of the Committee he submitted a letter in opposition to term limits. Dr. Budnitz remarked he does not believe the reasons put forward in support of term limits, that long service results in too close a relationship with DCPP personnel and the local community and that over a long period of service oversight becomes lax and results in fewer recommendations, are valid. Dr Budnitz explained in some detail whey be believes this is not the case. Dr. Budnitz expressed his view that the appointment discretion should remain with the entities and officials that now appoint the Committee's members. Dr. Budnitz remarked he did not feel it would be appropriate for the Committee as a body to take a position on the issue of term limits for membership. Dr. Budnitz expressed his personal view and conviction that the intent behind the term limits proposal was principally motivated by the desire to remove him, Dr. Peterson and former member Dr. Lam from the Committee so that other people might be brought onto the panel. Dr. Budnitz provided examples of how incumbent members were exempted from the imposition of term limits on other bodies and why a limit should not apply to incumbents. He further stated he discussed this issue with the Attorney General's staff during the meeting last month. Dr. Peterson stated in his view the CPUC should seek advice on the matter of term limits for DCISC membership from the entities that appoint its members and the question is really how much discretion on the appointment process do those agencies wish to maintain. He remarked it is reasonable for the DCISC to inform the appointing entities of the issue. Mr. Rathie summarized the direction to counsel was to formally advise the CPUC to seek advice from the appointing entities and to notify the entities as to the existence of the proposal and to advise that the Committee as a body takes no position on the issue.

            Mr. Hon reviewed the topic in Phase 2 of the methodology for the Committee's funding during the period of extended operation. He reported PG&E made a proposal that included input received from Mr. Rathie which would provide baseline funding in an amount equal to the average of the Committee's expenditures for calendar years 2023, 2024 and 2025, or the amount now provided per previous CPUC decisions whichever is greater with any funds unspent in a calendar year returned to PG&E for credit to the ratepayers providing the funds. This amount would be increased each year in an amount equal to the increase in the Consumer Price Index not to be less than 3%. For overspending in any calendar year the DCISC would provide an invoice to PG&E at the commencement of the following year along with a 10% contingency. Mr. Hon reported the Alliance for Nuclear Responsibility expressed general agreement with this proposal. Mr. Rathie observed that at present, should the Committee expend more in any calendar year than it receives in funding in that event the Committee begins the next year with a deficit. He remarked preliminary estimates are that the new funding formula may result in approximately a 13% increase in funding for the Committee over the existing formula. Senior Director Mr. Tom Jones observed PG&E believes the proposal is reasonable and is linked to California cost increases. Mr. Jones reported there is now a provision in the DCISC Third Restated Charter which provides for budgetary discretion over the budgeted amount in the event a shortfall is incurred as a result of public communication activities by the Committee. Mr. Hon remarked the direction from the Committee on this issue is that the Committee supports the proposal by PG&E.

            Mr. Hon reviewed the revisions to the Committee's current Charter which have been proposed in Phase 2 and reported the Small Business Utility Advocates proposed that recommendations made by the Committee go in a more direct and rapid fashion to the CPUC and to the NRC. The Alliance for Nuclear Responsibility has opposed the proposed change and PG&E has argued such a revision to the Charter is not necessary as the current provisions are adequate. Mr. Hon reported the Small Business Utility Advocates have also proposed that the Committee have immediate and enforceable power to address urgent operational safety issues as the emerge. Dr. Peterson observed a key point is that the Committee has no enforcement authority for its recommendations and it is through the entities appointing its members that the recommendations receive effective and substantial leverage. Dr,. Budnitz observed the Committee also has a direct link to the NRC resident inspection team through its frequent meetings with the resident inspectors at DCPP and he remarked Part 21 of the NRC regulations provide an avenue for any citizen to report a safety concern to the NRC. Mr. Hon observed and the Committee Members agreed the apparent direction is to provide input that the proposed revisions to the Charter are not necessary.

            Mr. Hon reported the final regulatory issue which concerns the DCISC in Phase 2 pertains to the provision of the funds for its operation which the Small Business Utility Advocates suggest should require PG&E to provide funding for the Committee's operation to the CPUC and for the CPUC to then provide those funds to the DCISC. He observed that PG&E has stated its position that this change is not necessary. The Alliance for Nuclear Responsibility has indicated it does not object to the proposed change. Mr. Rathie commented that at this point everything has worked well as far as the funding and the timing of the funding for the Committee's operations including the additional funding received for its transition and relicensing activities and adding a role for the CPUC in the matter would probably complicate and delay the receipt of the required funding. He observed by past practice the Committee accesses its annual funding on a quarterly basis and must at all times operate on a "cash and carry" basis with respect to its activities. The Committee members were then in agreement that this proposed revision is simply not necessary.

            Mr. Hon summarized the Committee's position on the issues he briefed: (1) concerning term limits to let the appointing entities know about the pending proposal and inform them the Committee does not have a formal position on the matter; (2) concerning funding methodology the Committee supports the position of PG&E; (3) concerning the Charter revision and funding logistics proposals the Committee believes those proposals are not necessary. Mr. Hon reported the parties have filed and submitted their opening and reply comments in Phase 2 and the Commission is working on a proposed decision. Mr. Hon stated with Mr. Rathie they will put the Committee's positions on these issues into a brief to be submitted to Mr. David Zizmor of the CPUC Energy Division.          

            The Members then took up the matter of ratification of Amendment No. 4 to the Contract with Dr. Mark Kirk to increase its not to exceed amount of $100,000. On a motion by Dr. Budnitz, seconded by Dr. Peterson, Amendment No. 4 was ratified.

            The Members discussed engaging in the search directed earlier for a consultant or consultants to undertake a peer review of the seismic contentions raised by Dr. Peter Bird and they observed the Committee requested Dr. Bird to document his concerns in a report suitable for peer review. Dr. Kadak observed this review might need to wait for receipt of a suitable report. Dr Meshkati volunteered to work on the matter including assembling a list of possible candidates together with counsel and the Committee's consultants to conduct the interview process. Dr Budnitz invited the members of the public present to provide names for consultants who might be suited for this task and the members and consultants discussed assembling a strong list of potential subject matter independent experts and to return the matter to the Committee at the Februry 2025 public meeting. Dr. Peterson observed the subject matter experts who addressed the Committee at this public meeting each identified gaps in information which would be necessary to have from Dr. Bird in order to conduct an appropriate review and he commented at present identification of those gaps would be required in order to conduct a sufficient review. Dr. Budnitz commented if may be necessary to engage more than one consultant for this review and Dr. Peterson commented as Dr. Meshkati is leading the process of identifying consultants part of that task will be identifying the disciplines needed.

            Mr. Rathie called the Committee's attention to the two draft Committee policies in the agenda packet for consideration. He reported the first is a policy which would document the Committee's present practice of reviewing fact finding reports in a manner which precludes the sharing of information between the members in the interim between public meetings. The second policy proposes a protocol for a response by the Committee in the event of an event notification at the power plant.

            Concerning establishing a policy for a Committee response to events at the plant Mr. Rathie remarked that it would be important for the Committee not to interfere with the response, but he stated the Committee does have a responsibility to understand the nature of an event so that the Committee may be in a position to inform the entities that appoint its members and he observed the Committee does have a role for public outreach, although during an event that would not be its primary function. He reported Senior Director Tom Jones and Ms. Brandy Lopez reviewed the draft policy and have provided suggestions. Mr. Rathie stated at this time the second policy concerning a Committee response to an event was not before the Members for approval but rather for information and discussion and he observed this might be an appropriate topic to address in a future fact finding. Mr. Rathie reported Consultants McWhorter and Wardell have been instrumental in the development of this policy. Dr. Peterson remarked his principal concern is related to the Committee's lack of regulatory or enforcement authority and he remarked the most counterproductive outcome would be if the Committee were to serve as a distraction or impediment to those entities that do have those explicit responsibilities. Consultant McWhorter reported that his input on the policy stemmed from his experience during the earthquake at the North Anna Nuclear Power Plant in Virginia when he was representing the minority owner, as the minority owner is not a part of the emergency response organization but needed to have access to a flow of information on the situation. He remarked there is no intent to be intrusive in this effort, but it is very valuable to have a plan for maintaining access to information when a real event occurs and on occasion rumors can start after an event and the Committee needs to be prepared for questions from the public. PG&E Senior Director Mr. Tom Jones remarked there are ways to employ the DCISC's expertise during an event and he observed the appointing authorities already have defined roles in the State of California's incident command structure and he suggested the DCISC might function on behalf of the public as a technical liaison. He suggested the DCISC review this issue with the San Luis Obispo County Office of Emergency Services and the Governor's Office of Emergency Services and the NRC. Dr. Peterson agreed that this is a good topic to take up in a future fact finding and he offered to sponsor the topic in that context. Dr Budnitz observed the most likely scenario might be that the policy would come into play after an event had successfully terminated and questions are being posed in which case the Committee could be thrust into the discussion and it would be prudent to have groundwork laid so the Committee could respond effectively.

            On a motion made by Dr. Budnitz, seconded by Dr. Meshkati, the Committee unanimously adopted Committee Policy 8 "Review of Fact Finding Reports."

            Mr. Rathie provided his report on financial matters and reported the Committee is currently solvent, but if expenditures continue for the remainder of 2024 as they did for the same period in 2023 the Committee will have overspent the funds it receives both from the PG&E ratepayers and under the Diablo Canyon Transition and Relicensing Memorandum Account which was set up in part to fund transition and relicensing activities by the Committee. He reported that overspending would be recouped in 2025 but as the Committee must always operate on a "cash and carry" the matter of having an adequate cash flow is always of great import to the Committee's operations.

            Mr. Rathie reported the DCISC website has been averaging 365 visits per month and the traffic increases during those months when the Committee conducts its public meetings. Visitors come largely from the United States following by visitors from Canada, China, South Korea, India, Brazil and Japan. He reported the website includes informational videos on the DCISC and on DCPP operations and photos of the Committee members and Consultants during fact finding. He remarked the DCISC informational video has become somewhat dated and in the event the Committee conducts future tours with members of the public it would be good to update the video.

            Consultant McWhorter remarked he has discussed with Consultant Wardell changing how the Committee documents recommendations in its fact finding reports. He observed the current practice is to generally document the DCISC's internal conclusions and infrequently recommendations to PG&E. Mr. McWhorter stated their proposal is to include recommendations by the fact finding teams to the Committee separately from those directed to PG&E and to clearly and specifically document that distinction and at the conclusion of the fact finding report summarize the recommendations made by category. Dr. Meshkati commented he believes Consultant McWhorter's suggestion that the Committee document recommendations by the fact finding teams to the Committee as a whole has merit and he commented in his review of past fact finding reports he found there were very good recommendations that the fact finding teams made to the Committee as a whole and he commented the reports could also serve to document recommendations made to the Committee's appointing agencies. Dr. Peterson expressed his support and commented that the reduced number of recommendations made by the DCISC to PG&E over the past few years is principally due to the fact that a recommendation is not needed because the action is or has already been taken by DCPP and in that case the Committee expressed the action as a Concern. Dr. Budnitz observed the Committee needs to remain cognizant of the threshold for making a recommendation and he remarked he believes the current threshold employed by the Committee is appropriate and he commented the proposal to include recommendations the Committee in the reports is a good idea. He also remarked and observed that the number of recommendations made by the Committee to PG&E has declined over past years due to changes by PG&E and not due to a change in the threshold for the Committee to make a recommendation and he warned against any tendency to lower the threshold in order to simply make more recommendations. The consensus of the Committee was to adopt Mr. McWhorter and Consultant Wardell's suggestion concerning future fact finding reports.

            Mr. David Weisman of the Alliance for Nuclear Responsibility was recognized. Mr. Weisman read from two paragraphs which concern the Alliance for Nuclear Responsibility's proposal for term limits for membership on the DCISC from his organization's Opening Comments in Phase 2 of the present CPUC rulemaking proceeding concerning the extension of operations by DCPP. He stated the proposal would limit membership to two three-year terms and is modeled on the seven-year limit the NRC imposes on its resident inspection teams at individual power plants. Mr. Weisman stated his view that SB 846 codified the DCISC's responsibilities to be more proactive and assertive than the DCISC has performed for the last ten years. He reported the new legislation, Public Utilities Code 712.1 characterizes the DCISC's purpose as to make findings and recommendations appropriate to enhance and improve safety. He contrasted this with what he described as more passive responsibilities described in CPUC Decision 88-012083 which he stated described as assessing and monitoring safety. Mr. Weisman observed the DCISC has had a steady decline in its recommendations, as from 2001 to 2014 there were a total of 66 recommendation and since then there has been only single recommendation made which was made following the passage of SB 846. He described the current members of the DCISC as individuals of exceptional distinction who have each contributed valuable public service, but he reported their initial terms on the Committee commenced in 2004, 2007 and 2009 respectively and he remarked his organization has asked the CPUC to consider whether a mechanism for gradual turnover in the members would better meet the public's expectations as created by SB 846. Mr. Weisman stated the Alliance's emphasis is on what he described as the newly adopted designation of enhance and improve safety with recommendations and not a remedial action over past occurrence, but it is in response to a perception that improvement can be made rather than as a form of compensatory behavior.

            Mr. Bruce Severance was recognized. Mr. Severance thanked the DCISC for its dedication to safety and commented it was his perception there is sincerity in the Committee's effort to review safety issues. He remarked there was debate about adding the DCISC to a role in the event of an emergency and that could create discord in the response and he stated he disagrees with such a conclusion. He remarked he believes the DCISC would have a responsibility to participate and bring attention to the issues as they arise even though other agencies may be involved and he stated he hoped each member of the Committee would see it as a duty to respond without creating confusion and in a proactive effort in furtherance of adding to a concerted effort toward a reasonable solution if an event were to arise.      

            Dr. Peterson asked Consultant Wardell to lead the review of the 34^th Annual Report.

B.        Approval of the DCISC 34^th Annual Report on the Safety of Diablo Canyon Nuclear Power Plant Operations, July 1, 2023 – June 30, 2024.

            Mr. Wardell reported that the draft of the Committee's 34^th Annual Report for the period July 1, 2023 through June 30, 2024 has been through several reviews and the Executive Summary, including the Committee's Conclusions and Recommendations, was part of the public agenda packet for this meeting. Dr, Meshkati thanked Mr. Wardell for assembling the report and remarked while he has no issues with regard to its contents, as he was not a member of the DCISC during the report period it would not be appropriate for him to vote on its approval. Dr. Budnitz observed he was satisfied with the Executive Summary and the sections of the report concerning seismic safety. Dr. Budnitz then offered a motion that the Committee accept the Annual Report as presented which was seconded by Dr. Peterson. Dr. Peterson observed the report includes a specific recommendation to PG&E that while the results from testing of surveillance Capsule B from Unit 1 are not necessary to assure Unit 1 reactor vessel embrittlement is acceptable with reference to the five-year extension, the DCISC recommends that Capsule B be removed during the next refueling outage for Unit 1 and that a reevaluation of reactor vessel integrity including both for PTS and USE be performed when the new data from Capsule B becomes available.

            Mr. Rathie proposed, and the members agreed, as many computers no longer have CD readers, that for the 34^th Annual Report copies continue to be produced in USB format but not in CD format.

            Mr. Rathie remarked in its 34^th Annual Report the Committee has made a formal recommendation to the CPUC that the CPUC and all other necessary California state authorities support the funding of plant upgrades recommended by DCPP.

            Ms. Julie Mansfield Wells, speaking as a member of the public, was recognized. Ms. Wells thanked the Committee and welcomed Dr. Meshkati. Ms. Wells requested that Dr. Digby Macdonald and Dr. Peter Bird's reports as well as Mr. Severance's communications to the DCISC be included in the 34^th Annual Report. Dr. Peterson confirmed those documents are included in the report as exhibits [in Volume II] as well as posted on the DCISC's website.

            Mr. Bruce Severance was recognized. Mr. Severance stated the vote earlier in the meeting to include Dr. Kirk's Report in the 34^th Annual Report was tantamount to an endorsement unless other views including those of Dr. Macdonald are included. Mr. Severance stated his view that the Committee should either clearly endorse or not endorse Dr. Kirk's Report. Mr. Severance remarked he believes any ambiguity to be dangerous due to circumstances in connection with the 2011 Westinghouse PTS evaluation and its revision of RT_PTS value uncertainty ranges of all prior reports and calculations which he stated he has debated with Dr. Kirk in connection with what he termed a gross under prediction in a 1987 Report. He stated he has submitted a report to the DCISC showing a seven fold increase in the likelihood of a PTS event which he characterized as the new information the Committee has asked to see. He further remarked the Capsule Y data report states the results of the analysis are within range which he stated makes the actual value 268°F. which he stated is at the screening limit by the end of license. He commented none of the capsule reports clearly state what the embrittlement values are as to the end of license and Dr. Kirk has admitted this and informed Mr. Severance they are reported elsewhere. Mr. Severance stated he has not seen those reports after having read 5,000 pages of information in the NRC docket in this matter and he is concerned the DCISC may not have seen the data. He stated endorsement of Dr. Kirk's Report is to him highly questionable.

            Dr. Peterson commented the discussion on Unit 1 reactor vessel embrittlement in the Executive Summary of the 34^th Annual Report contains a set of conclusions that the Committee reached as part of drafting the Annual Report and those conclusions are being approved. Dr. Peterson emphasized the Committee is going to continue to investigate this question in some depth. He reported it currently appears the Unit 1 reactor vessel is in compliance with NRC requirements for embrittlement and that it will remain in compliance for the five year period of the license extension, although information from Capsule B's removal could change the longer term conclusions.

            The Committee then voted, with two Members in favor and Dr. Meshkati abstaining, to approve the DCISC's 34^th Annual Report on the Safety of Diablo Canyon Nuclear Power Plant Operations for the period July 1, 2023 through June 30, 2024.

XXX    CONCLUDING REMARKS & DISCUSSION BY COMMITTEE MEMBERS OF FUTURE DCISC ACTIVITIES

                        A.        Future Actions by the Committee.

                        B.        Further Information to Obtain/Review.

                        C.        Confirmation of Future Site Visits, and Public Meetings.

            In response to a Committee question, PG&E Senior Director Mr. Tom Jones reported PG&E has a sufficiency determination from the NRC which allows the continued operation of DCPP. He reported the license renewal process has two tracks, one for safety and the second for environmental issues. He reported there will be meetings in November 2024 on environmental issues and DCPP has a referral to the California Coastal Commission for a Coastal Zone Management Act consistency review of the Coastal Commission's original report to the California Secretary of Natural Resources. Mr. Jones stated the California Legislature stated a coastal development permit was not required and PG&E developed its application for consistency based on that understanding and was informed late in the process that thinking on the matter had evolved and a permit was being required. Mr. Jones said that PG&E does not believe the requirement for a coastal development permit is valid and PG&E is now in negotiation with the agencies involved. He observed the legislation provides for five years of extended operation and the license renewal action with the NRC is for 20 years' reauthorization of operation. Mr. Jones stated there are some issues to be resolved in this context between the NRC and the state processes, but he confirmed these issues are not holding up the license renewal process with the NRC as they are not now on the critical path but he stated they could be in the future.

            Mr. Jones reported that Mr. Severance earlier in this meeting gave a brief and vague update about a threatening correspondence addressed to the Diablo Canyon Decommissioning Engagement Panel and Mr. Jones reported this matter has been referred to the appropriate law enforcement agencies.

XXXI ADJOURNMENT OF THE ONE HUNDRED AND NINTH PUBLIC MEETING

            There being no further business, DCISC Chair Dr. Per Peterson expressed his appreciation to all participants in this public meeting, to PG&E and DCPP senior management, to the AGP Video team, and to the members of the public for their active participation and to the other members and the technical consultants of the DCISC. The Chair then adjourned the afternoon session and this 109^th public meeting at 4:45 p.m.