ML20344A430
| ML20344A430 | |
| Person / Time | |
|---|---|
| Issue date: | 12/02/2020 |
| From: | Advisory Committee on Reactor Safeguards |
| To: | |
| Burkhart, L, ACRS | |
| References | |
| NRC-1259 | |
| Download: ML20344A430 (76) | |
Text
Official Transcript of Proceedings NUCLEAR REGULATORY COMMISSION
Title:
Advisory Committee on Reactor Safeguards Docket Number:
(n/a)
Location:
teleconference Date:
Wednesday, December 2, 2020 Work Order No.:
NRC-1259 Pages 1-55 NEAL R. GROSS AND CO., INC.
Court Reporters and Transcribers 1323 Rhode Island Avenue, N.W.
Washington, D.C. 20005 (202) 234-4433
NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com 1
1 2
3 DISCLAIMER 4
5 6
UNITED STATES NUCLEAR REGULATORY COMMISSIONS 7
ADVISORY COMMITTEE ON REACTOR SAFEGUARDS 8
9 10 The contents of this transcript of the 11 proceeding of the United States Nuclear Regulatory 12 Commission Advisory Committee on Reactor Safeguards, 13 as reported herein, is a record of the discussions 14 recorded at the meeting.
15 16 This transcript has not been reviewed, 17 corrected, and edited, and it may contain 18 inaccuracies.
19 20 21 22 23
1 UNITED STATES OF AMERICA 1
NUCLEAR REGULATORY COMMISSION 2
+ + + + +
3 681ST MEETING 4
ADVISORY COMMITTEE ON REACTOR SAFEGUARDS 5
(ACRS) 6
+ + + + +
7 OPEN SESSION 8
+ + + + +
9 WEDNESDAY 10 DECEMBER 2, 2020 11
+ + + + +
12 The Advisory Committee met via Video-13 Teleconference, at 9:30 a.m. EST, Matthew W.
14 Sunseri, Chairman, presiding.
15 16 COMMITTEE MEMBERS:
17 MATTHEW W. SUNSERI, Chairman 18 JOY L. REMPE, Vice Chairman 19 WALTER L. KIRCHNER, Member-at-large 20 RONALD G. BALLINGER, Member 21 DENNIS BLEY, Member 22 CHARLES H. BROWN, JR. Member 23 VESNA B. DIMITRIJEVIC, Member 24 JOSE MARCH-LEUBA, Member 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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2 DAVID A. PETTI, Member 1
PETER RICCARDELLA, Member 2
3 ACRS CONSULTANT:
6 DESIGNATED FEDERAL OFFICIAL:
9 ALSO PRESENT:
10 JOSEPH ASHCRAFT, NRR 11 JORDAN HOELLMAN, NRR 12 IAN JUNG, NRR 13 SCOTT MOORE, Executive Director, ACRS 14 JOHN SEGALA, NRR 15 DINESH TANEJA, NRR 16 STEPHEN VAUGHN, Public Participant 17 SANDRA WALKER, ACRS 18 19 20 21 22 23 24 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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3 C-O-N-T-E-N-T-S 1
2 Roll Call and Opening Remarks by the ACRS Chairman 3
4 New Design Review Standard for Chapter 7 5
(Instrumentation and Control - I&C): Lessons Learned 6
as a Result of Recent New Reactor Licensing Reviews 7
Related to I&C 8
9 John Segala 8
................ 10 11 Joseph Ashcraft
................ 15 12 Opportunity for Public Comment 13 Stephen Vaughn................. 53 14 Adjourn..................... 55 15 16 17 18 19 20 21 22 23 24 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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4 P-R-O-C-E-E-D-I-N-G-S 1
9:30 a.m.
2 CHAIR SUNSERI: Well, good morning. It's 3
9:30 and the meeting will now come to order. This is 4
the second day of the 681st meeting of the Advisory 5
Committee on Reactor Safeguards. I'm Matthew Sunseri, 6
Chair of the ACRS, and I'll now call the roll to 7
confirm communications and a quorum.
8 I'll start with Ron Ballinger.
9 COMMISSIONER BALLINGER: Here.
10 CHAIR SUNSERI: Dennis Bley?
11 COMMISSIONER BLEY: Here.
12 CHAIR SUNSERI: Charles Brown?
13 COMMISSIONER BROWN: Here.
14 CHAIR SUNSERI: Vesna Dimitrijevic?
15 COMMISSIONER DIMITRIJEVIC: Here.
16 CHAIR SUNSERI: Walt Kirchner?
17 COMMISSIONER KIRCHNER: Here.
18 CHAIR SUNSERI: Jose March-Leuba?
19 MEMBER MARCH-LEUBA: Yes.
20 CHAIR SUNSERI: Dave Petti?
21 COMMISSIONER PETTI: Here.
22 CHAIR SUNSERI: Joy Rempe?
23 VICE CHAIR REMPE: Here.
24 CHAIR SUNSERI: Pete Riccardella?
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5 COMMISSIONER RICCARDELLA: I'm here.
1 CHAIR SUNSERI: All right. Good. We have 2
a quorum. The designated federal officer for this 3
meeting is Ms. Christina Antonescu. During today's 4
meeting the Committee will consider the following: We 5
will have a presentation on the New Design Review 6
Standard for Chapter 7, Instrumentation and Control, 7
I&C, lessons learned, as a result of recent new 8
reactor licensing reviews related to I&C. And 9
following that we will get into preparation of a 10 report on that topic.
11 A bridge line -- a phone bridge line has 12 been opened to allow members of the public to listen 13 in on the presentation and Committee discussions.
14 We've received no written comments or requests to make 15 oral statements from members of the public regarding 16 today's session. There will be an opportunity for 17 public comment and we have set aside time in the 18 agenda for comments from members of the public 19 attending or listening to our meeting. Written 20 comments may be forwarded to Ms. Christina Antonescu, 21 the designated federal officer.
22 A transcript of the open portions of the 23 meeting is being kept and it is requested that the 24 speakers identify themselves and speak with sufficient 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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6 clarity and volume so that they may readily be heard.
1 Additionally, participants should mute themselves when 2
not speaking. I reviewed the -- what appears to be 3
the course of the agenda yesterday afternoon before we 4
recessed, and so today we will get into this topic, 5
but before we get started I need to let you know that 6
I've got some unavoidable personal conflicts with my 7
schedule today between 1:00 and 4:00 p.m. During this 8
time our Vice Chair, Joy Rempe, will be presiding over 9
the meeting.
10 And just looking at the agenda it's 11 possible that we could be completed with today's 12 activities before 4:00, so if so, Joy may recess the 13 meeting until 9:30 tomorrow, or she may use the 14 available time at the discretion of the Committee 15 consistent with the published agenda. Does any other 16 member -- do any members have any comments before we 17 get started with the topic of today?
18 All right. Then at this point I will turn 19 to Member Charles Brown to lead us on the subject.
20 Charlie?
21 COMMISSIONER BROWN: Let me un-mute my mic 22 and maybe we can get started.
23 (Laughter.)
24 COMMISSIONER BROWN: The mouse doesn't 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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7 mouse. Okay. I'm Charles Brown, the Chairman of the 1
Instrumentation and Control Subcommittee. Today's 2
presentation will be by the staff on the New Design 3
Review Guide for Instrumentation and Controls in Non-4 Light Water -- for Non-Light Water Reactor Reviews.
5 We've had two Subcommittee meetings on this. If my 6
memory serves me properly, I believe they were June 7
the 2nd of this year and October 21st of this year.
8 As a result of that second meeting, which 9
we had some very crisp interactive discussions which 10 were very productive, I passed on a number of comments 11 that we had made back to the staff. They have 12 proposed revisions to that, to the document that we 13 reviewed back on October 21st and they will be 14 presenting their resolution of those particular 15 comments -- or their response, excuse me, to those 16 particular comments with any discussion that the 17 members might like to carry out. And I asked them to 18 include some backup slides such that if it wasn't 19 clear, they could pull those slides up and make it a 20 little bit clearer as to what kind of changes they 21 made.
22 So those changes would be the ones that 23 end up based on the feedback we got when they gave us 24 the responses were the only significant changes to the 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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8 document that we reviewed back in October. So I will 1
ask them to confirm that when I turn it over. Let me 2
see if I've missed anything. I think today our 3
presenters will be John Segala, the branch manager, 4
Jordan Hoellman and Joe Ashcroft -- excuse me, Joe 5
Ashcraft. Excuse me, Joe.
6 So with that in mind, John, I will turn it 7
over to you for your opening remarks.
8 MR. SEGALA: Good morning. Thank you, 9
Member Brown. Yes, my name is John Segala. I'm Chief 10 of the Advanced Reactor Policy Branch in the Division 11 of Advanced Reactors and Non-Power Production 12 Utilization Facilities in the Office of Nuclear 13 Reactor Regulation.
14 The purpose of today's briefing is to 15 provide the Full Committee an overview of the Design 16 Review Guide for Instrumentation and Controls. We 17 appreciate the observations and the comments we 18 received from the Subcommittee during the ACRS 19 meetings in June and October. We have made proposed 20 changes to the Design Review Guide to address the ACRS 21 comments and shared the changes with Member Brown.
22 The presentation today will summarize 23 these proposed changes to the Design Review Guide.
24 The staff plans to issue the Design Review Guide with 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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9 the proposed changes after receipt of the ACRS letter.
1 I want to quickly take this opportunity to 2
place this effort in context with the staff's broader 3
efforts to develop advanced reactor guidance. The 4
development of the Instrumentation and Control Design 5
Review Guide was started to identify and apply 6
insights and lessons learned from past new reactor 7
application reviews that are important to be captured 8
and addressed in order for the Agency to be ready to 9
-- for future new and advanced reactor licensing 10 applications.
11 The Design Review Guide was initiated 12 prior to and for the most part was developed 13 separately from the Commission-approved Licensing 14 Modernization Project, and before the recent start of 15 activities associated with the industry-led 16 Technology-Inclusive Content of Application Project, 17 TCAP, and the staff-led Advanced Reactor Content of 18 Application Project, ARCAP, which will provide 19 guidance for risk-informing the scope and level of 20 detail of an application. Both TCAP and ARCAP are 21 based on the Licensing Modernization Project. The 22 staff plans to brief the ACRS on TCAP and ARCAP 23 efforts next calendar year.
24 More recently as the instrumentation and 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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10 control guidance was further developed it incorporated 1
concepts from the Licensing Modernization Project.
2 The staff believes that the guidance for 3
instrumentation and control in the Design Review Guide 4
provides an important example of how a review can be 5
performed using concepts from the Licensing 6
Modernization Project. We're looking forward to 7
hearing from the ACRS Full Committee on this important 8
topic and any insights and feedback that you all may 9
have. At this point I could turn it over to Jordan 10 Hoellman to begin the presentation.
11 MR. HOELLMAN: Great. Thanks, John. This 12 is Jordan Hoellman. I'm a project manager in the 13 Advanced Reactor Policy Branch in NRR and I'm pleased 14 to be here again to present on the Design Review Guide 15 for Instrumentation and Controls.
16 So I'm moving onto the second slide, the 17 agenda slide. So the I&C Design Review Guide, or DRG, 18 provides guidance for the NRC staff to use in 19 reviewing the I&C portions of applications for 20 advanced non-light water reactors within the bounds of 21 existing regulations. This guidance leverages the 22 NuScale Design-Specific Review Standard, or DSRS, 23 Chapter 7 framework while factoring in lessons learned 24 from new reactor reviews.
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11 The guidance supports the NRC's vision and 1
strategy near-term Implementation Action Plans, or 2
IAPs, specifically IAP Strategy 3 which involves 3
developing guidance for flexible regulatory review 4
processes for non-light water reactors within the 5
bounds of existing regulations and a new non-LWR 6
regulatory -- a new advanced reactor regulatory 7
framework that is risk-informed and performance-based 8
and features staff's review efforts commensurate with 9
the demonstrated safety performance of advanced 10 reactor technologies.
11 So quickly to go over the agenda, we'll 12 provide a refresher on how the new DRG is organized 13 around the fundamental principles and how the review 14 process will ensure that each principle is met in the 15 design. We'll then discuss the proposed revisions to 16 the DRG that we plan to make based on ACRS 17 observations from our June and October Subcommittee 18 meetings. And then we will plan to issue the DRG 19 following receipt of the ACRS letter.
20 At the October Subcommittee meeting we 21 presented on some of the comments we received during 22 the public comment period. The resolutions to the 23 public comments did not impact how the fundamental 24 principles are applied by the reviewer in the DRG and 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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12 the resolutions to the public comments did not modify 1
the DRG concepts that were presented in the June and 2
October meetings.
3 So next slide. I'll briefly discuss here 4
how the DRG was revised early in 2020 to align with 5
the Licensing Modernization Project. So the NRC 6
engaged with the Licensing Modernization Project, or 7
LMP, that was led by Southern Company and coordinated 8
by the Nuclear Energy Institute and costs shared by 9
the U.S. Department of Energy. The LMP's objective 10 was to develop technology inclusive risk-informed and 11 performance-based regulatory guidance for licensing 12 non-light water reactors for the NRC's consideration 13 and possible endorsement.
14 The LMP document, or NEI 18-04, outlines 15 an approach for use by reactor developers to select 16 licensing basis events, or LBEs, classify structure 17 systems and components, determine special treatments 18 and automatic controls and to assess the adequacy of 19 a design in terms of providing layers of defense-in-20 depth. In the Staff Requirements Memorandum, or SRM, 21 to SECY-19-0177 the Commission approved the use of the 22 methodology described as a reasonable approach for 23 establishing key parts of the licensing basis and 24 content of applications for licensee -- licenses, 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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13 certifications and approvals for non-light water 1
reactors.
2 Following receipt of the SRM the NRC 3
published Reg Guide 1.233 in June 2020, which endorses 4
with clarifications the principles and methodologies 5
in NEI 18-04 as one acceptable method for determining 6
the appropriate scope and level of detail for parts of 7
applications. The methodology described in NEI 18-94 8
and the Reg Guide also provided general methodology 9
for identifying appropriate scope and depth of 10 information to be provided in applications to the NRC.
11 The DRG has been coordinated to align with 12 the risk-informed performance-based LMP framework and 13 provides review guidance on all aspects of safety-14 significant I&C systems which include safety-related 15 I&C systems and I&C systems that are not safety-16 related but warrant special treatment. For example, 17 per NEI 18-04 safety-significant functions include 18 those classified as risk-significant or credited for 19 defense-in-depth.
20 Although the DRG aligns with the LMP 21 framework, the DRG provides the flexibility for staff 22 to perform I&C reviews for applications that do not 23 implement the LMP framework. The staff will continue 24 to ensure that the DRG aligns with the industry-led 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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14 Technology-Inclusive Content of Application Project, 1
the NRC-led Advanced Reactor Content of Application 2
Project, and other advanced reactor initiatives 3
including the future Part 53 regulatory framework.
4 The staff has already had a few meetings 5
with the ACRS on the Part 53 and has scheduled routine 6
meetings with the ACRS on Part 53 and 20.21. And as 7
John mentioned, the ACRS will also be briefed on the 8
TCAP and ARCAP efforts in 2021.
9 I just wanted to take an opportunity to 10 note that an ACRS Subcommittee observation and NEI 11 comment we received on the DRG noted that the DRG 12 methodology could be used for the evaluation of any 13 new reactor design, light water reactor or non-light 14 water reactor. While the NRC staff agrees that the 15 DRG is technology inclusive and can be used to review 16 any new reactor application, it was developed to 17 address the immediate needs associated with the non-18 LWR community and was intended to be consistent with 19 Reg Guide 1.233 and NEI 18-04, which also include the 20 four non-light water reactors in their titles.
21 So with that I'll turn it over to Joe 22 Ashcraft to go through the evolution of I&C review 23 guidance, unless there are any questions. Go ahead, 24 Joe.
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15 COMMISSIONER BROWN: Is Joe there?
1 CHAIR SUNSERI: I think he's on mute if 2
he's talking.
3 MR. ASHCRAFT: Oh. Now can you hear me?
4 COMMISSIONER BROWN: Got it. Go ahead.
5 MR. ASHCRAFT: Sorry about that. I 6
thought I did un-mute myself. All right. Once again 7
thank you, Jordan. Hello, my name is Joe Ashcraft and 8
I'm the I&C technical reviewer at NRR. I was part of 9
the team for the development of the NuScale Design-10 Specific Review Standard and I'm part of the team for 11 the Design Review Guide.
12 So just a little background of how we got 13 here is the SRP is our primary staff guidance. And 14 this -- and we used it and it has been effective in 15 large light water reviews, but due to its nature the 16 use of the SRP for new reactor reviews had not always 17 been optimized as best they could. However, the staff 18 wanted to improve how we did I&C reviews for small 19 modulars by removing requirements that no longer apply 20 to the small modular reactors. Example: IEEE Standard 21 279, and removing duplicate reviews of the same 22 requirement as they reviewed in -- as many were 23 reviewed in each of the seven sections of the SRP.
24 So along with the Commission's policy that 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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16 required us to develop a design-specific review 1
standard for each application for efficiency and 2
effectiveness, the staff took the opportunity to 3
develop the DSRS and -- it's significantly different 4
from the SRP. It is simpler, more risk-informed, 5
safety-focused while incorporating some lessons 6
learned from our other new reactor reviews.
7 Our primary objectives were to improve the 8
safety focus staff reviews by ensuring an applicant 9
had sufficient licensing bases details presented in 10 their applications to clearly demonstrate that the 11 applicable regulations are met and fundamental I&C 12 design principles are addressed. And we'll be able to 13 improve the efficiency of the reviews by eliminating 14 unnecessary information from being documented and 15 reviewed and by approving guidance to avoid 16 unnecessary and repeated RAIs.
17 So just to highlight, we were in close 18 coordination with the ACRS throughout our development 19 of the DSRS and we had multiple interactions with the 20 Committee. And early availability with the applicants 21 along with close preparation coordinations with the 22 applicant was essential. Unlike other previous new 23 reactor applications, the NuScale I&C review was a 24 huge success at efficiency and effectiveness. It was 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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17 completed earlier than most other areas with no 1
significant challenges.
2 So now we're at the DRG, and it's an 3
evolution of the DSRS. So it reflects the safety-4 focused approach from the DSRS including the four 5
fundamental I&C design principles and simplicity, but 6
was developed while factoring in the feedback from 7
lessons learned from other reviews. And the next 8
slide will discuss the goals of this document.
9 So slide 5, please? So the goal -- the 10 DRG goal is to modernize I&C safety reviews in support 11 of non-advanced -- of advanced non-light water 12 licensing applications. Success within this goal or 13 objective will be reflected by simpler, streamlined 14 and agile I&C review and regulatory infrastructure 15 that will effectively address I&C designs for new and 16 advanced non-light water reactors.
17 The I&C DRG was initiated as a proactive 18 way to modernize I&C safety review of advanced non-19 light water applications and is demonstrated by the 20 experience with the NuScale DSRS I&C review. The 21 staff believes that the DRG will lead to more 22 efficient and effective reviews. Making it available 23 for non-light water designs early will help establish 24 predictable and efficient I&C reviews while the common 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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18 goal of safety is ensured.
1 So the DRG supports the NRC version --
2 NRC's vision and strategy for advanced reactor safety 3
reviews as it could be used for advanced reactors with 4
vastly different technology. Also the DRG allows for 5
the flexibility of the review process within the 6
bounds of the existing regulation.
7 An ACRS Subcommittee observation from June 8
20th and an NEI comment furnished too noted that the 9
methodology could be used for evaluating any new 10 reactor design. And I think as Jordan said that while 11 we agree with that, it was specifically developed for 12 non-light water advanced reactors.
13 So next slide, please? So this is sort of 14 the I&C framework. And if you look at the top two 15 levels above the blue box, they're performed by the 16 Core Review Team with I&C support as necessary. This 17 review will formulate what is required for the I&C 18 staff to evaluate and the I&C reviewer would focus on 19 verifying the applicable attributes of the I&C design 20 that supports the plant-level performance objectives 21 as depicted by the Core Review Team.
22 So the blue box depicts the flow of the 23 review, the full I&C review. The I&C staff will be 24 evaluating that the demonstration -- that the I&C 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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19 performance objectives have been met in terms of 1
reliability of the I&C design and robustness of the 2
I&C design. Okay. Reliability is the probability 3
that a design, that a system or component will meet 4
its minimum performance requirements under plant 5
conditions. Quantitative and qualitative performance 6
measures and criteria are used in support of this 7
portion of the assessment. And that's to the right 8
side of the blue box.
9 And robustness of the design -- I'm sorry.
10 That's to the left of the blue box. Robustness of the 11 I&C design, which is the degree a system or component 12 can function correctly in the presence of invalid 13 inputs or stressful environment conditions. Defense-14 in-depth performance measures are used in support of 15 this portion of the assessment via the use of 16 fundamental I&C design principle from the DSRS as well 17 as the qualification measures such as quality.
18 The figure was revised to show that the 19 fundamental I&C principles show up, so one of our 20 previous Subcommittees -- the blue box in the center 21
-- or this bubble in the center of the blue box would 22 identify the I&C principles for -- I mean, it was in 23 the guide but it wasn't in this figure, so we just 24 added them. So the I&C reviewer should confirm that 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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20 the applicant has established the appropriate set of 1
design principle -- principle design criteria, 2
applicable industry consensus standards and applicable 3
NRC regulatory guidance documents that will be used to 4
ensure the performance measures, defense-in-depth 5
levels and qualitative measures are met.
6 And finally, the I&C should interface with 7
other technical disciplines to verify that any cross-8 disciplines issues are adequately identified and 9
resolved. And that's shown in this bottom bubble 10 below the blue box. So and one of the things we 11 learned with the DSRS we needed better coordination 12 with all the other chapters. I mean, we had it 13 before, but we really started creating more meetings 14 to discuss their issues and our issues and how they 15 conflict with one another. So we just carried that 16 forward and it worked out well.
17 So slide 7. So this just depicts the I&C 18
-- here's how the I&C will work within the DRG.
19 First, we're going to focus on the architecture and 20 system functions available. Optimally this portion of 21 the review is started during pre-application meetings.
22 And as Charlie has noted many times in his crisp 23 observations, getting a look at the architecture goes 24 a long way just to understanding the whole I&C design 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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21 review and whether it's going to be simple or complex.
1 COMMISSIONER BROWN: Joe, can I interrupt 2
you just a second?
3 MR. ASHCRAFT: Sure, Charlie.
4 COMMISSIONER BROWN: Okay. Just --
5 MR. ASHCRAFT: Mr. Brown.
6 COMMISSIONER BROWN: -- listening to your 7
development as to how we eventually got here, one 8
thing that I recall; I went back and looked at this 9
just yesterday because I thought I remembered all of 10 this, back around 2010, a little bit earlier than 11 that, this idea of addressing architecture as opposed 12 to piece-parts, you know, that were more of a top-13 down, was addressed not quite in the detail that we do 14 now, but in ISG 6, the licensing process, the Interim 15 Staff Guidance document, which you all prepared, which 16 we reviewed and wrote a letter on -- that was back in 17 September of 2010. I know we viewed that as kind of 18 a precursor to where we ended up with the DSRSs and 19 everything after we went through the first couple of 20 design certifications.
21 So I just wanted to bring that up so that 22 the members would understand that there was what I 23 call some precursors to some of this stuff that set 24 kind of the architecture as the top-level thing we 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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22 should be looking at. Just for amplification. Okay?
1 Thanks. I'm done.
2 MR. ASHCRAFT: Thank you, Mr. Brown. So 3
the second IRO the staff reviewed focuses on safety 4
and risk-significant functions and selected structure 5
systems and components, SSCs, that support them to 6
ensure that the I&C performance objectives are met.
7 And then finally, reduced or less staff review efforts 8
on SSCs that are not safety-related without special 9
treatment. Specifically the staff's review focuses on 10 ensuring that these SSCs will not inhibit performance 11 of the safety-significant functions.
12 So next slide, slide 8. So you guys --
13 members of the Full Committee, you probably heard this 14 many times, but I just wanted to highlight the four 15 principles plus simplicity, and I'll just briefly go 16 through each one of them.
17 So redundancy. The review should evaluate 18 the level of redundancy used in a safety-related 19 system to ensure that no single failure results in the 20 loss of safety functions and removal from service of 21 any component or channel does not result in the loss 22 of required minimum redundancy unless except if 23 reliability of operation of the I&C can be otherwise 24 demonstrated.
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23 Independence. The objective is to 1
evaluate the methods described in the application used 2
to demonstrate independence of I&C systems between 3
redundant portions of safety-related systems such as 4
redundant revisions, safety-related systems and the 5
effects of a licensing base event, and three, between 6
the safety-related systems and systems that are not 7
safety-related.
8 The staff should also assess the role of 9
independence in I&C systems designed as not safety-10 related but warranting special treatment. The 11 reviewer should evaluate the physical logical 12 interfaces of the I&C system design including specific 13 performance information and the purpose of that 14 information and the meanings asserted in that 15 information.
Example:
hardware or data 16 communications. The review should include not only 17 permanent interfaces but also temporary connections.
18 Example: for maintenance work stations.
19 Diversity.
20 COMMISSIONER BROWN: Let me -- Joe, let me 21 interrupt one more second.
22 MR. ASHCRAFT: Sure.
23 COMMISSIONER BROWN: I'm not disagreeing 24 with anything you said on the redundancy and 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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24 independence points. All well-taken. The point I 1
would just like to wrap that around, there is no 2
redundancy without independence. Okay? You don't 3
need independence if you don't have redundancy. Those 4
two are kind of the linchpins of everything having to 5
do with the architecture. And so that's why the 6
emphasis in most of our reviews have been focused on 7
that as well as how diversity is brought into the 8
picture. So I'll let you go on. I just wanted to 9
make sure that the connection between redundancy and 10 independence is emphasized for the record, because you 11 don't have one without the other. Thanks, Joe.
12 MR. ASHCRAFT: Okay. Let's see, I think 13 a member of team, Ian Jung, wanted to say something.
14 Are you able to un-mute, Ian?
15 MR. JUNG: Can you hear me?
16 MR. ASHCRAFT: Yes.
17 MR. JUNG: Yes. No, I was just checking 18 whether I can speak to it. I just want to mention one 19 thing that -- regarding Joe's diagram earlier. The 20 staff -- the diagram of the whole -- you know, big 21 picture is a simplification of the -- yes, I 22 appreciate that. This is Ian Jung in NRR.
23 I just want to mention that some of the 24 defense-in-depth measures:
independence and 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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25 redundancy, diversity, as well as qualification 1
measures, are very closely related to also reliability 2
portion on the left. So there are interrelated. I 3
just want to highlight that it's not a totally 4
separation of two different concepts, that they are 5
related to each other. And that's why it's shown at 6
the -- near the top of the blue box. Reliability and 7
robustness are interrelated there. I just want to 8
mention that. Thank you.
9 MR. ASHCRAFT: Okay. Thanks, Ian. So I 10 guess we're on diversity. The reviewer should 11 evaluate the common cause failure analysis results 12 provided by the applicant to verify that a potential 13 CCF due to latent systematic faults within the digital 14 I&C system will not result in exceeding the applicable 15 radiological release limits.
16 In performing this evaluation for which 17 event -- evaluating the safety analysis the applicant 18 should perform a D-3 assessment to determine whether 19 a potential CCF due to a systematic fault in the 20 digital I&C could disable a safety function. And two, 21 a diverse means not subject to the same common cause 22 failure is available to perform either the same 23 function different functions such that a
24 radiological release are not exceeded. Note that the 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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26 overall analysis of the licensing basis event and 1
related defense-in-depth assessments for safety 2
functions may include potential contributions from I&C 3
systems.
4 So let's go on to determination. And we 5
call it predictability and repeatability now, but the 6
reviewer should confirm that the application provides 7
a detailed timing analysis describing how the I&C 8
systems that support safety-significant functions 9
including supporting communication systems address the 10 concept of predictability and repeatability. A 11 reviewer should confirm that the application provides 12 sufficient information. For example, in the form of 13 architecture descriptions, functional block diagrams, 14 description of operation, to demonstrate that the 15 proposed digital I&C system's real-time performance is 16 predictable and repeatable.
17 And lastly, simplicity. So in the DSRS 18 simplicity was an appendix. And so we brought it into 19 the DRG, the forefront. So while review guidance for 20 simplicity is not expressly provided, the reviewer 21 should verify that the applicant has incorporated this 22 design in the concept. And what I mean by that is --
23 and it starts really with the architecture. I mean 24 when they provide the architecture, and depending on 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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27 the wires going in and out and just the confusion that 1
we've seen in past designs -- or not confusion, but 2
the complexity -- maybe that's the best word to use --
3 that that's sort of what we're looking for. And 4
there's other measures of simplicity that we would be 5
aspiring to.
6 So let's go to the next slide, slide 9.
7 So this gets into refinements based on ACRS feedback.
8 And one -- I'm just going to read the bullets here:
9 Improve the discussion in Section X.0.1.1., Scope and 10 Review. And the third paragraph, to solely focus on 11 the DRG intent and delete any reference to the type of 12 applications under review.
13 And two -- second bullet: Improve 14 discussions of Item 8,Section X.2.2.1.3, Diversity in 15 support of defense-in-depth to address common cause 16 failures on provisions of displays and controls.
17 And three, added a new Item 7 in Section 18 X.2.2.1.4, Predictable and Repeatable Behavior on 19 Watchdog Timers.
20 COMMISSIONER BROWN: Joe, can you hold on 21 a minute?
22 MR. ASHCRAFT: Sure.
23 COMMISSIONER BROWN: Bullets 2 and 3 are 24 pretty straightforward. The first one most people 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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28 don't -- probably don't -- won't remember this, but in 1
the item we reviewed on October 21st, in the preamble 2
part; I think it was like Section 1.1, the scope tried 3
to differentiate between the level of detail that you 4
might need less or more elements of review. And they 5
had separate out the items such as COLs, site permits, 6
certifications, operating licenses, manufacturing 7
licenses, et cetera, et cetera, and tried to 8
differentiate as to which ones may or may not need 9
more or less review.
10 Unfortunately, they put the design certs 11 in the not needing as much, so I made that 12 observation. Then the thrust of their refinement is 13 that they removed the attempt to try to differentiate 14 and just use that particular paragraph now to say 15 that, hey, you'll use the DRG to assess that the 16 applicant demonstrates all the parameters that we like 17 to see.
18 There's a copy of it if you wanted to read 19 it. It's on slide -- what -- I've forgotten what 20 slide it is, but that was the thrust of the thing.
21 And it's -- that way there's -- we're not trying to 22 make a differentiation as to what particular parts of 23 any -- applicants may submit. We're not going to tell 24 them -- tell the staff. They should review it to make 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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29 sure it meets the staff requirements, period.
1 So did I phrase that right, Joe?
2 MR. ASHCRAFT: Yes, you did. And I think 3
Jordan pulled up slide 14, which -- so we originally 4
were going to make -- refined your observations from 5
what the NEI comment was, but back and forth with OGC 6
and the fact that ARCAP and TCAP really is where this 7
information should revise. So that's why we decided 8
just to delete all that out of the DRG. And that --
9 as it states there, we're just going to assess I&C 10 systems in how they're demonstrate.
11 COMMISSIONER BROWN: Okay. Do any of the 12 members have any questions on that? I wanted to make 13 sure that was clear. It's a little bit muddy, but --
14 I mean it was if you don't -- if you're not steeped in 15 it.
16 Hearing none, go ahead, Joe. Thank you.
17 COMMISSIONER KIRCHNER: Yes, this is an 18 improvement, Charlie. This is Walt.
19 COMMISSIONER BROWN: Oh, yes.
20 COMMISSIONER KIRCHNER: Yes. Thank you.
21 COMMISSIONER BROWN: Definitely agree. I 22 was glad to see it. They initially thought about just 23 taking all the stuff up and not differentiating, and 24 then that obviously came out in subsequent discussions 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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30 with others that, hey, we ought not even be talking 1
about this. There's other documents that give good 2
direction on that. So this is a very good improvement 3
over what was there before. So thank you for --
4 thanks, Joe, for the amplification.
5 MR. ASHCRAFT: Okay. Thank you for 6
bringing it up. So let's go onto slide 10, if there's 7
no more questions on slide --
8 COMMISSIONER BROWN: Hold it. Go back 9
again. I'm going to work on you hard in this. I'd 10 like to hit each bullet and make sure that we make 11 what the specific changes were. So can you go to 12 slide 15?
13 MR. ASHCRAFT: Sure. I knew you were 14 going to do that, Mr. Brown, but --
15 COMMISSIONER BROWN: Well, I've been 16 through it in detail, but the members haven't had as 17 much opportunity as I've had.
18 MR. ASHCRAFT: Understood.
19 COMMISSIONER BROWN: And we did discuss 20 all these six items during the meeting, so go ahead.
21 MR. ASHCRAFT: Okay. So the change that 22 we made in Section X.2.2.1.3, as you can see here, 23 this is the exact -- I mean, this is the change that 24 we made. And what we wanted to do -- I think one of 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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31 the observations was main control room or outside. So 1
that is available, but we revised it so that it's very 2
clear as to what's needed, et cetera.
3 COMMISSIONER BROWN: Yes, their initial 4
change -- their initial version we reviewed just 5
deleted any references to a main control room and 6
there was a provision of a set of controls and 7
displays just accessible to the operator somewhere.
8 We commented that that seemed a little bit vague and 9
it -- like a main control room doesn't exist. So they 10 fixed that, and that's the way they fixed it, which is 11 also an improvement. Okay Joe, you can go on with the 12 last bullet on that page and then pick up slide 16.
13 MR. ASHCRAFT: Okay. Well, I think I'm 14 not going to go back to slides 9 and 10 because 15 they're just bulleted items of what we presented in 16 the backup slides.
17 COMMISSIONER BROWN: Okay.
18 MR. ASHCRAFT: So for the third bullet in 19 slide 9, if you go to the next slide, which is 20 slide --
21 COMMISSIONER BROWN: Sixteen.
22 MR. ASHCRAFT: -- 16. Yes. So this is 23 the change that we made for the predictability and 24 repeatability behavior, and I think the observation 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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32 was we needed to bring the watchdog timer part of it 1
from back in the Appendix A to this section. So as 2
opposed to just pointing back to that appendix we 3
decided just to bring in a new item which discusses --
4 and basically this is the item that --
5 COMMISSIONER BROWN: Which I totally agree 6
with.
7 MR. ASHCRAFT: All right. Well, if 8
there's no other questions from the Full Committee, 9
let's go to slide 17. So this just depicts the 10 bullets or the changes that we presented on slide 10, 11 but this is the actual changes made to the DRG. So 12 we'll just go with this slide.
13 So this is for control of access. And I 14 know we've had may crisp observations going back and 15 forth on this, but this is the change that we've come 16 up with and we hope that it clears everything up. And 17 basically we added to Item 3, Hardware Characteristics 18 that Enforce Unit Directional Communication Features.
19 Example: use of unit directional non-20 software base 3 that is connected to a transmitter in 21 the higher classified system and a receiver in the 22 lower classified systems are considered by the 23 applicant as the preferred means for mitigating any 24 hazards associated with the communication paths. And 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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33 needless to say, this will be as usual a high area of 1
focus in our reviews.
2 COMMISSIONER BROWN: This provided some 3
additional amplification that wasn't there before. It 4
just said you should look at communications. And 5
that's about all it said. So you can see it in the 6
first sentence, and they added some additional 7
clarification. And this reflects actually our 8
conclusions in subsequent and all of our other reviews 9
that we've done.
10 MR. ASHCRAFT: All right. So let's go 11 onto slide 18. And this was for an Appendix A, 12 Section A, multi-unit stations. The observation is 13 Items 1 and 2 seem to conflict, and so the -- oh, are 14 we -- did you -- okay. Yes. So we revised Item 1 as 15 stated and deleted Item 2. So hopefully that removes 16 the conflict that was brought up during the last 17 Subcommittee meeting. I'll let you take a look at it.
18 I don't guess I need to read it unless you want me to.
19 COMMISSIONER BROWN: I just wanted to 20 point out one thing to the members, which we will 21 probably also discuss later in the letter writing. In 22 the initial version of this if you look the lined-out 23 section, that was Item 1. And it said safety-related 24 I&C SSCs are not shared unless it can be shown that 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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34 they do not significantly impair the ability to 1
perform safety functions. And the second one then 2
said you shouldn't use them -- you shouldn't share 3
them at all.
4 So there was a conflict. This conflict 5
will still exist, as you see. The not-shared 6
statement is now the first sentence and the second 7
sentence now says almost the same thing except the 8
word significantly is deleted. Am I correct in that, 9
Joe?
10 MR. ASHCRAFT: I'm going to say yes to 11 that, and I -- yes.
12 COMMISSIONER BROWN: It's close enough.
13 MR. ASHCRAFT: Yes. I agree with you, Mr.
14 Brown.
15 COMMISSIONER BROWN: Significantly agree 16 that delete -- the -- significantly is in the Rule 55, 17 10 C.F.R. 55-something. And IEEE 603 says just 18 impaired.
19 MR. ASHCRAFT: Right.
20 COMMISSIONER BROWN: You all deferred to 21 the impaired from 603 because you retain -- still 22 retain the option to share fundamentally? And that 23 includes reactor trip and safeguard systems. There's 24 no differentiation in what type of safety-related SSCs 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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35 we're talking about.
1 MR. ASHCRAFT: That's correct.
2 COMMISSIONER BROWN: Okay. All right.
3 You can go on. Just wanted to make sure everybody 4
understood the differentiation.
5 MR. ASHCRAFT: Okay. Let's see, I guess 6
we're onto slide 19. So the concern or the 7
observation here was while -- how it was written 8
didn't necessarily reflect the best way the guidance 9
of the Reg Guides were used when we were looking at 10 this automatic and manual controls. And I believe 11 it's Reg Guide 1.62. But we revised the words here as 12 written to address the observation from the last 13 Subcommittee meeting. And bottom line is -- the last 14 sentence I guess says it all, is the connection should 15 not compromise the integrity of interconnecting cables 16 and interfaces between local electrical or electronic 17 cabinets and the plant's electrical mechanical 18 equipment.
19 And I guess the best to describe it, as 20 Charlie was about -- Mr. Brown was about ready to say, 21 is you want your manual controls to be independent 22 from the software, I&C safety system or digital 23 components.
24 COMMISSIONER BROWN:
- Yes, the key 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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36 amplification here is if you look at the lined-out 1
part, it -- after it goes through they should be 2
downstream and not compromise, the last sentence said 3
the manual controls may be connected either to 4
discrete hardwired components or to simple dedicated 5
and diverse software-based digital equipment that 6
performs the coordinated actions.
7 That just seemed to be counterproductive, 8
that you really want your manual controls to be 9
downstream. You don't want to be mucking with other 10 software processes that may compromise your manual 11 operations. So they've revised it to be consistent 12 with that. Am I correct in saying that, Joe?
13 MR. ASHCRAFT: That is correct, Mr. Brown.
14 COMMISSIONER BROWN: Thank you. Where are 15 we now?
16 MR. ASHCRAFT: Well, so I guess if you 17 jump up to slide 11, basically it's our next steps and 18 we look forward the ACRS' letter of recommendation.
19 And we're prepared to publish the final DRG in 2021, 20 or as soon as possible.
21 COMMISSIONER BROWN: Okay.
22 COMMISSIONER BLEY: This is Dennis Bley.
23 I know I've asked you this before, but I'd like to get 24 it today in our Full Committee meeting.
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37 Several times you mentioned that while 1
this was developed to support the LMP approach, it 2
really applies to any kind of reactor anywhere. And 3
your development was really based on to a large extent 4
lessons learned from LWR design certs over the last 10 5
years. And the next LWR design cert, if you had one, 6
really wouldn't use the current SRP; it would use 7
something very close to what you have here.
8 What's the link for a new LWR coming in to 9
get you to something that looks like this? Is it ISGs 10 that you have or how do you update that SRP? And when 11 do you think you might really update the SRP?
12 MR. ASHCRAFT: Well, I think I'll let 13 Dinesh Taneja address this because they are working on 14 a revision to the SRP, but keep in mind the SRP really 15
-- so for existing reactors, if they come in with an 16 amendment that say just affects RPS or whatever -- so 17 it's kind of broken out into systems as opposed to any 18 new reactor design which would be coming in totally 19 digital for the most part where say RPS and SFAS are 20 in the same platform, et cetera. You don't really 21 need to do both chapters in the SRP to accomplish the 22 review. So that's sort of how we progressed from the 23 SRP.
24 But having said that, I think it would be 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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38 up for the application coming up and our management to 1
establish what kind of guidance we would be using to 2
review their application, whether it be similar to the 3
DSRS or this DRG, which either one could review any 4
new application coming in. But it's just a matter of 5
how it be determined up front before it gets to the 6
I&C.
7 COMMISSIONER BROWN: Well, Joe, I've read 8
this thing. Just to amplify Dennis' comment -- is 9
that okay, Dennis? Did I interrupt you or did you 10 want to follow up or can I make an --
11 COMMISSIONER BLEY: That's fine, Charlie.
12 I'm glad you're going to because I -- it's just a 13 little less that satisfying right now.
14 COMMISSIONER BROWN: Yes, that's --
15 exactly that's my response. I mean I've read this 16 thing four times now beginning to end and you made the 17 differentiation between somebody coming in with a 18 license amendment to maybe just replace the RPS and 19 SFAS systems with new computer-based on integrated 20 systems like this.
21 And there's another -- for the life of me 22 I can't see any differentiation at all in any of the 23 requirements or any that we would -- if I would -- if 24 it was me -- up to me, I would use this to review a 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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39 license amendment because it's got all the elements of 1
the architecture in it. And all your connection 2
points to go out to other existing pipes, valves, 3
pumps, et cetera are still the same. So I think --
4 COMMISSIONER BLEY: And it incorporates 5
the lessons learned that you've actually used in the 6
last reviews.
7 COMMISSIONER BROWN: Exactly. When you 8
look at Diablo Canyon, it meets this in spades. All 9
the elements you call out in this Design Review Guide 10 are easily covered and absorbed into that Diablo 11 Canyon review.
12 MR. TANEJA: This is Dinesh Taneja. Let 13 me -- I guess there's couple efforts that are underway 14 right now. Your points, Mr. Brown, are very well-15 taken and we are taking all these into consideration, 16 but there is a project which is the SRP Modernization 17 Project that's underway right now where we are going 18 back and visiting Chapter 7 of the SRP to see how we 19 can address some of these issues, the lessons that 20 we've learned and best practices that -- how we move 21 forward with that.
22 And in addition to that, there is a 23 parallel effort. There is an ISG being developed to 24 support possibly looking at a Part 50 application for 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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40 a small modular light water reactor and --
1 COMMISSIONER BROWN: Why wouldn't this 2
apply to the BWRX-300's RPS system?
3 MR. ASHCRAFT: Precisely.
4 MR. TANEJA: Right. So what we are doing 5
is -- I think there is an ISG being put together where 6
we are basically in the ISG -- I think what we are 7
pointing towards is use of maybe the DSRS of NuScale 8
and the DRG in combination and then evaluating the 9
design for a small modular reactor.
10 So there are those two parallel efforts 11 that are underway right now that we're trying to 12 figure out how to get this concept into that.
13 COMMISSIONER BROWN: But it sounds to me 14 like you're trying to drive your car through the same 15 tracks that you went before, but you're going to allow 16 yourself to wander off course. I mean --
17 MR. TANEJA: Well --
18 (Simultaneous speaking.)
19 COMMISSIONER BROWN: Dinesh, let me finish 20 first here --
21 MR. TANEJA: Okay.
22 COMMISSIONER BROWN: -- please? Thank 23 you. There -- well, I almost lost my thought here.
24 You've -- the template -- this DRG is an expansion of 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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41 the mPower DSRS and whatever changes you all made for 1
the NuScale. I'm not sure you made any at all. I 2
mean, fundamentally it looked like you used the mPower 3
DSRS for that review. I mean, that's what 4
fundamentally what we -- I did. Same approach.
5 So it's difficult to understand why we 6
want to generate new documents when this particular 7
DRG has been rewritten in such a manner to be 8
virtually complete for anything. Why try to duplicate 9
it in some other verbiage? That's just -- I think 10 that -- to Dennis to I that seems -- correct me if I'm 11 wrong, Dennis -- that just doesn't seem to be 12 efficient or productive.
13 MR. TANEJA: I understand exactly your 14 point. And so I think the approach is overall SRP 15 issue and how we had taken the opportunity when we 16 were asked to prepared DSRS to really revamp Chapter 17
- 7. And now I think we are again same challenge.
18 There is the effort to address the SRP modernization 19 as a whole. And then how Chapter 7 gets addressed, we 20 have the opportunity right now to clean that up.
21 COMMISSIONER BROWN: Why not just put 22 Chapter 7 onto this and stick it in the SRP?
23 MR. TANEJA: Well, that might be the way 24 to go.
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42 COMMISSIONER BROWN: How about --
1 MR. TANEJA: That's a possibility.
2 COMMISSIONER BROWN: You want a hint from 3
us?
4 MR. TANEJA: Yes.
5 COMMISSIONER BROWN: We'll probably --
6 COMMISSIONER KIRCHNER: I would -- this is 7
Walt. I would second that. The one objection I've 8
had through this all along is this non-LWR 9
nomenclature. I just -- so I just want to reinforce 10 your and Dennis' points. I just don't see why we're 11 narrowing this down to non-LWR. And when we know, or 12 at least anticipate -- there's likely to be an 13 advanced LWR concept coming in and this should fit 14 fine for the purposes of that review.
15 MR. JUNG: Yes, this is Ian Jung, 16 technical staff in the NRR. I just want to mention 17 that I think at the staff level having involved in 18 this effort we fully understand the Committee members' 19 position and desire. I think technically we agree.
20 Yes, I just want to -- I don't want to go too far 21 here, but I think this whole non-LWR versus 22 technology-inclusive nature, this not unique to the 23 particular area.
24 And in addition -- and it say just the 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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43 dynamics of certain efforts where some are more 1
progressive and more risk-informed and some are not.
2 And when we -- for example, if we bring the light 3
water reactors, then we need to go through whole lot 4
of the engagement and concurrence, and it could 5
potentially delay that and we'll end up dealing with 6
non-concurrence and other topics. That's the nature 7
of where we are. There are people who are not 8
necessarily -- might have brought up on some of these 9
concepts.
10 And I just want to share that that's --
11 I'll take -- I'll put that as my personal opinion, but 12 I think the decision to expand this non-LWR guide into 13 more technology inclusive nature -- I personally 100 14 percent agree, but I think it's a matter of the 15 management and the resources to go with it and 16 potentially delaying the schedule aggregations of 17 this. That's some down side to it. That's -- I just 18 want to share that perspective.
19 MR. SEGALA: And this is John Segala.
20 Just from a bigger picture, we're undertaking a large 21 effort to develop 10 C.F.R Part 53, the new 22 technology-inclusive risk-informed performance-based 23 regulation of advanced reactors as required by the 24 NEIMA Law. And that -- in NEIMA they revised -- in 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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44 January of 2019 they revised the definition of 1
advanced reactors to include non-light water reactors, 2
light water, small modular reactors, as well as fusion 3
reactors.
4 So as we -- and we're going to be engaging 5
extensively with ACRS on that whole effort. We plan 6
to use -- to utilize the existing efforts that we've 7
done on the Licensing Modernization Project, which we 8
endorsed in a Reg Guide, but we endorsed it only for 9
non-light water reactors. Again, that effort, even 10 though it was endorsed only for non-light water 11 reactors, is a technology-inclusive methodology, which 12 theoretically could be used no matter what the reactor 13 technology is.
14 And so as -- and then the TCAP and ARCAP 15 projects that I talked to that are content of 16 application projects looking at how you build your 17 application for the NRC to review and risk-inform that 18 is also a technology-inclusive process, but is also 19 focused on non-light water reactors. But as we use 20 those -- moving into the future as we develop Part 53, 21 Part 53 is going to have to also work for the light 22 water SMRs. And so we're going to be making sure that 23 the guidance moving forward as it supports Part 53 as 24 one acceptable way of meeting the regulations, that 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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45 that guidance, even though it's -- it was originally 1
approved only for non-light water reactors because 2
it's technology-inclusive, would be applicable to 3
light water SMRs as well.
4 And so sort of as we started off on 5
advanced reactors, we were originally focusing 6
advanced reactors only on non-light water reactors, 7
but then as NEIMA has expanded the scope things have 8
changed. A lot of other light water SMRs have started 9
engaging in NRC in pre-application activities. So 10 we're trying to move forward and make progress on 11 guidance that we developed -- started developing many 12 years ago. And we're trying to get those issued, but 13 also to help some of the early movers for the non-14 lights, but also to try to have a longer-term vision 15 of how we're going to make all this fit in with Part 16 53 as we develop that. And there will be numerous 17 ACRS meetings on Part 53 as well as TCAP and ARCAP.
18 I don't know if any of that's helpful.
19 COMMISSIONER BROWN: Well, I will -- I'm 20 just going to make an observation based on this. And 21 I'm not criticizing. I mean, you've gone through what 22 you guys are going through, but fundamentally this 23 document is about as technology-neutral as you can 24 get. You can risk-inform anything you want to. I 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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46 mean, about the only thing you can risk-inform on a --
1 for a reactor protection system is you don't have one.
2 I think that's kind of hard to imagine for any reactor 3
that's a fission reactor, a fusion reactor, or 4
anything else, that it's so safe that we don't need to 5
know what it's doing anytime and don't have to be able 6
to shut it down quickly. And it's independent of any 7
reactor characteristic type. It's totally neutral 8
from that.
9 You could build this -- a fusion reactor.
10 It doesn't matter.
You're going to have 11 instrumentation to protect it or provide some type of 12 safeguard as they're defined for that particular 13 reactor design. And this guide would apply for any 14 types of electronics that you apply. I mean you could 15 build them out magnetic amplifiers or vacuum tubes, or 16 discrete transistorize. You'd be kind of foolish, but 17 you could do that.
18 MR. SEGALA: Well, and I --
19 COMMISSIONER BROWN: So I mean, I just 20 have a hard time seeing wasted effort on spinning your 21 wheels on rewriting what you've already written. This 22 is -- after 12 years of working on this, this is the 23 best compilation I've seen over the last times we've 24 been doing it to address any new design, whether it's 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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47 a light water, a large light water, a small SMR light 1
water, a non-light water, whatever. It doesn't 2
matter. This document does not differentiate anywhere 3
within it other than the words in your preamble about 4
non-light water. That's all. End of --
5 (Simultaneous speaking.)
6 MR. SEGALA: And I think also to make this 7
document work and be consistent, be able to work 8
within the licensing modernization framework you have 9
to keep in mind that LMP uses a lot of similar 10 terminology that's used in the light water reactor 11 world, but some of those definitions have changed as 12 we define them in the Licensing Modernization Project.
13 So to just take a document that was 14 originally developed for non -- that was developed to 15 try to work for non-light water reactors and then made 16 to work within the LMP and then just change the title 17 to say this automatically works for a light water 18 reactor that was -- didn't us LMP, it may create some 19 challenges to go back and make sure that the 20 terminology and the definitions that we have in here 21 work no matter where -- what framework you've designed 22 your facility under.
23 COMMISSIONER BLEY: John --
24 COMMISSIONER KIRCHNER: John, this is Walt 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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48 Kirchner. I'm sorry, Dennis. Go ahead.
1 COMMISSIONER BLEY: I'd go back to where 2
I started. You mentioned wasted effort; I agree with 3
that, but the main thing we're concerned about is this 4
is an evolution of how you've been reviewing I&C 5
systems for light water reactors. And it's applicable 6
to the non-light water reactors. And if you start 7
rethinking and doing things, you're going to lose --
8 the worry -- my worry is you're going to lose some of 9
what you've gained in terms of simplicity and clarity 10 in how you do the reviews. But for me that's enough 11 said.
12 COMMISSIONER KIRCHNER: If I may, Dennis, 13 I just -- I agree with you. And, John, maybe -- you 14 know, things do change. They evolve. What's on your 15 plate is different than probably what you were looking 16 at when the LMP was first envisioned. But this is 17 just one member's opinion. I would just recommend not 18 constantly putting non-LWR in these documents. Just 19 call them advanced reactors or whatever. But for all 20 the reasons Charlie and Dennis cited, this works and 21 it's derivative from your experience with NuScale.
22 And you are evolving towards a technology-inclusive or 23 neutral, or whatever the current terminology is.
24 And then just one further observation.
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49 Whether it's I&C or it's PRA, in all these areas the 1
advanced LWRs are probably going to have the most 2
mature experiential base to back them up. So the best 3
tested LMP and the risk-based approach would probably 4
be an advanced LWR because it's going to have the most 5
database experimental operational controls, everything 6
to back up the estimates that are used and selection 7
of design-basis events, et cetera, et cetera.
8 So I just -- I think we've lodged; or at 9
least I have, this objection many times in the past.
10 I just would recommend that you don't keep propagating 11 this non-LWR terminology in these documents because 12 you've come up with something that's really flexible 13 and inclusive in terms of technologies and yet it kind 14 of starts out with a preamble that boxes it out for an 15 advanced LWR concept. Enough said.
16 COMMISSIONER BROWN: Are there any other 17 members that have a comment or would like to weigh in?
18 COMMISSIONER PETTI: Charlie, I agree with 19 all the discussion and what the members have said.
20 COMMISSIONER BROWN: Okay. Thank you, 21 Dave.
22 COMMISSIONER PETTI: Yes.
23 COMMISSIONER BROWN: Matt, is it time for 24 me to go request public comment?
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50 CHAIR SUNSERI: Charlie, if this is the 1
conclusion of the staff's presentation and members 2
have no questions about the presented material, then 3
yes, you may turn to the public line.
4 COMMISSIONER BROWN: Okay. Let me make 5
sure one more time. Staff, are you -- I think it's --
6 probably we've now spent the last discussion to a 7
fair-the-well. So do you have any other comments 8
you'd like to make relative to the discussions we've 9
had so far before I got hit the members again and then 10 hit the public comments?
11 Absence of silence -- absence of noise, 12 rather, would say you agree -- you don't. One last 13 round, members. Anybody else have anything else 14 before I go off to the public line?
15 MR. ASHCRAFT: I'm sorry. This is Joe 16 Ashcraft. I've been trying to cut in several times, 17 but my microphone was muted.
18 COMMISSIONER BROWN: Okay.
19 MR. ASHCRAFT: I just want to thank Mr.
20 Bley for starting this conversation. And we agree 21 with your comments and look forward to this being in 22 your letter, because I think that would be a way to 23 let our management see the issue as much as any issue 24 that would be in your letter. Anyway, so if you'd go 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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51 to slide 12, that's the end. That's my smoke stack.
1 So the staff is done unless there's any questions.
2 COMMISSIONER BROWN: Okay. Hearing 3
nothing else from the members, is the public line 4
open?
5 MR. DASHIELL: Public bridge line is open.
6 COMMISSIONER BROWN: Okay. Is there 7
anybody on the public line that would like to make a 8
comment? Is there anybody in the public --
9 (Simultaneous speaking.)
10 MR. VAUGHN: -- Brown, this is Steve 11 Vaughn with NEI. Can you hear me?
12 COMMISSIONER BROWN: Say that again?
13 MR. VAUGHN: This is Stephen Vaughn with 14 the Nuclear Energy Institute. Can you hear me?
15 COMMISSIONER BROWN: Yes. Yes.
16 MR. VAUGHN: Okay. Yes. Thank you. This 17 is again Steve Vaughn with the Nuclear Energy 18 Institute and I just had one comment to make. In 19 reviewing the most recent revision of the Design 20 Review Guide I wanted to point specific attention to 21 Section 2.2.1.3 entitled Diversity in Support of 22 Defense-in-Depth to Address Common Cause Failures.
23 And, Member Brown, just to kind of 24 continue with your analogy with the cars and the 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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52 tracks, a lot of what they've got in here comes from 1
a SECY from 1993, and that addressed diversity in 2
defense-in-depth and various software common-cause 3
failure. And take your -- whatever the popular car 4
was in 1993, it sounds like this starts again in 2020, 5
take whatever electric car you want now, but that car 6
is driving the same tracks. And so one high-level 7
comment I want to make is that this car should be on 8
a new set of tracks.
9 So I feel like it's been -- the guidance 10 here is 30 years old. The state-of-the-art in how to 11 do a digital design to minimize systematic failures 12 and design defects that would -- could cause common-13 cause failures with the safety-related components that 14 the digital I&C is designed to control an instrument, 15 this is new state-of-the-art. And I'd just ask that 16 the 10 sort of criteria we have in this section --
17 I'd just offer -- I know it's kind or somewhat late in 18 the game, but maybe start with a blank slate. Maybe 19 we can just -- with what we know now and all the 20 techniques we have now that do elegant design in 21 digital I&C we -- maybe these 10 steps will actually 22 take us down the wrong path. Maybe there's a better 23 way to do this. And, so that's a high-level comment.
24 And one specific comment is in Appendix D 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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53 of this -- in the Design Review Guide for this 1
section. It articulates what sort of disciplines that 2
NRC would need to do the review. And for this section 3
the PRA Group isn't even one of the groups to help 4
support the review. And I would offer that if you 5
mention the term common-cause failure, I think you 6
should bring the risk analyst folks in, because they 7
have a lot of expertise to offer in this area. Thank 8
you.
9 COMMISSIONER BROWN: Okay. Thank you very 10 much, Dave. Is there anyone else on the line that 11 would like to make a public comment?
12 Hearing none, we'll close the public line.
13 Is Thomas on the line to --
14 MR. DASHIELL: Public bridge line is 15 closed.
16 COMMISSIONER BROWN: Thank you very much, 17 Thomas. Matt, with that I think I'm through. I'll 18 pass it back to you.
19 CHAIR SUNSERI: All right. Thank you, 20 Charlie. So let me ask you do you have a draft report 21 prepared for review?
22 COMMISSIONER BROWN: Yes.
23 CHAIR SUNSERI: All right. And I'll ask 24 Scott or Larry, is Sandra available to -- or whoever 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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54 you have to pull up our draft letter?
1 MR. MOORE: This is Scott. Well, let's 2
ask. Sandra, are you on right now?
3 MS. WALKER: Yes.
4 MR. MOORE: Can you -- do you have 5
Charlie's letter to pull up?
6 MS. WALKER: Yes.
7 MR. MOORE: Okay. So, Matt, there's the 8
answer.
9 CHAIR SUNSERI: Okay. Great. Thank you.
10 So, Charlie, I think we could go forward with a read-11 through. And then following that we would get comment 12 from the members on major comments. And then 13 depending on what work may need to be necessary after 14 their major comments, we could go into them either 15 line-by-line or we could send you off to address the 16 major comments. But that's kind of the two forks in 17 the road I see right at this point. So why don't we 18 go ahead with the read-through and then we'll take it 19 from there.
20 COMMISSIONER BROWN: Is everybody okay 21 break-wise?
22 CHAIR SUNSERI: Oh, that's a good 23 question. I got a little ahead of myself. It's 24 10:45. So let's take a 15-minute break to -- well, 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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55 let's see, members like a little longer break, so 1
let's take a 30-minute break to 11:15.
2 (Whereupon, the above-entitled matter went 3
off the record at 10:46 a.m.)
4 5
6 7
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Design Review Guide (DRG):
Instrumentation and Controls for Non-Light Water Reactor (Non-LWR) Reviews Advisory Committee on Reactor Safeguards (ACRS) Full Committee Meeting December 2, 2020 1
- Introduction/Background
- Overview of instrumentation and controls (I&C) DRG for non-LWR application reviews
- Fundamental I&C Design Principles
- Overview of revisions to the DRG to address ACRS observations from the subcommittee meetings 2
Agenda
3 Licensing Modernization Project
- Licensing Basis Events (LBEs)
- Classification of Structures, Systems, and Components (SSCs)
- Defense-in-Depth (DID)
SSCs Including Radionuclide Barriers Safety Related (SR)
SSCs Non-Safety Related SSCs with Special Treatment (NSRST)
Non-safety Related SSCs with No Special Treatment (NST)
SSCs selected for required safety functions to mitigate DBEs within F-C Target*
SSCs performing risk significant functions SSCs performing functions required for defense-in-depth SSCs performing non-safety significant functions SSCs selected for required safety functions to prevent high consequence BDBEs from entering DBE region beyond F-C target Risk Significant SSCs Non-Risk Significant SSCs
- SR SSCs are relied on during DBAs to meet 10 CFR 50.34 dose limits using conservative assumptions
- NUREG-0800, Standard Review Plan (SRP) Chapter 7
- System-based approach for light-water reactor (LWR) licensing reviews
- Guidance not suitable for non-LWRs applications
- NuScale Design-Specific Review Standard (DSRS)
Chapter 7
- Improved safety-focused licensing review approach
- Improved licensing reviews efficiency and effectiveness
- DRG for I&C
- Leverages the DSRS concepts
- Leverages lessons learned from recent new reactor I&C licensing reviews 4
Evolution of I&C Review Guidance
Goals 5
- Modernizes the I&C safety review in support of advanced non-LWR licensing applications
- Supports the NRCs vision and strategy for advanced reactor safety reviews
- Incorporates principles from Regulatory Guide (RG)-
1.233 Safety-focused Risk-informed Technology-Inclusive Performance-based
I&C System Review Framework 6
Overall Review Approach 7
Architecture
- The NRC staff review starts at the I&C architecture level
- Ensure that the information necessary to understand the proposed I&C architecture and system functions are available Safety-Significant Functions
- The NRC staff review focuses on safety-significant functions and selected SSCs that support them
- Ensure that the I&C performance objectives are met Functions Not Safety-Significant
- The design-related review for SSCs that the NRC staff determined are not safety-related and not risk significant should be less
- The NRC staff review focuses on ensuring that failure or operation of such SSCs will not prevent other SSCs from performing their safety-significant functions or adversely affect DID adequacy
8
Refinements based on ACRS Feedback
- Improved discussion in Section X.0.1.1 (Scope of Review), third paragraph to solely focus on the DRG intent and deleted any reference to the type of applications under review.
- Improved discussion in Item 8 of Section X.2.2.1.3 (Diversity in Support of Defense-in-Depth to Address CCFs) on provision of displays and controls.
- Added a new Item 7 in Section X.2.2.1.4 (Predictable and Repeatable Behavior) on Watch Dog Timer.
9
Refinements based on ACRS Feedback (Cont.)
- Added discussion in Item 3 of Appendix A, Section A.6 (Control of Access), on hardware characteristics that enforce unidirectional communication feature(s).
- Improved discussion in Appendix A, Section A.8 (Multi-Unit Stations) on sharing safety-related I&C SSCs among nuclear power plant units.
- Improved discussion in Appendix A, Section A.9 (Automatic and Manual Control) on manual controls.
10
Status and Next Steps
- ACRS letter of recommendation
- Prepare/publish final DRG in 2021 11
12
- CCFs - common cause failures
- DID - defense-in-depth
- DRG - Design Review Guide
- DSRS - design-specific review standard
- I&C - instrumentation and controls
- LBE - licensing basis event
- LWR - light water reactor
- non-LWR - non-light water reactor
- RG - Regulatory Guide
- SRP - standard review plan
- Section X.0.1.1, Scope of Review - Page X-2 and X-3 14 Backup Slides - Proposed Revisions
- Section X.2.2.1.3, Diversity in Support of Defense-in-Depth to Address CCFs, Item 8 - Page X-19 15 Backup Slides - Proposed Revisions
- Section X.2.2.1.4, Predictable and Repeatable Behavior, add Item 7 - Page X-20 16 Backup Slides - Proposed Revisions
- Appendix A, Section A.6, Control of Access, Item 3 -
Page X-29 17 Backup Slides - Proposed Revisions
- Appendix A, Section A.8, Multi-Unit Stations, Items 1 and 2 - Page X-31 18 Backup Slides - Proposed Revisions
- Appendix A, Section A.9, Automatic and Manual Control - Page X-32 19 Backup Slides - Proposed Revisions