ML22095A007
| ML22095A007 | |
| Person / Time | |
|---|---|
| Issue date: | 03/18/2022 |
| From: | Advisory Committee on Reactor Safeguards |
| To: | |
| Snodderly, M, ACRS | |
| References | |
| NRC-1888 | |
| Download: ML22095A007 (124) | |
Text
Official Transcript of Proceedings NUCLEAR REGULATORY COMMISSION
Title:
Advisory Committee on Reactor Safeguards BWRX-300 Subcommittee: Open Session Docket Number: (n/a)
Location: teleconference Date: Friday, March 18, 2022 Work Order No.: NRC-1888 Pages 1-80 NEAL R. GROSS AND CO., INC.
Court Reporters and Transcribers 1716 14th Street, N.W.
Washington, D.C. 20009 (202) 234-4433
1 1
2 3
4 DISCLAIMER 5
6 7 UNITED STATES NUCLEAR REGULATORY COMMISSIONS 8 ADVISORY COMMITTEE ON REACTOR SAFEGUARDS 9
10 11 The contents of this transcript of the 12 proceeding of the United States Nuclear Regulatory 13 Commission Advisory Committee on Reactor Safeguards, 14 as reported herein, is a record of the discussions 15 recorded at the meeting.
16 17 This transcript has not been reviewed, 18 corrected, and edited, and it may contain 19 inaccuracies.
20 21 22 23 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 UNITED STATES OF AMERICA 2 NUCLEAR REGULATORY COMMISSION 3 + + + + +
4 ADVISORY COMMITTEE ON REACTOR SAFEGUARDS 5 (ACRS) 6 + + + + +
7 BWRX-300 GE-HITACHI TOPICAL REPORT, "BWRX-300 8 CONTAINMENT EVALUATION METHOD" SUBCOMMITTEE 9 + + + + +
10 OPEN SESSION 11 + + + + +
12 FRIDAY 13 MARCH 18, 2022 14 + + + + +
15 The Subcommittee met via Video 16 Teleconference, at 1:00 p.m. EDT, Jose March-Leuba, 17 Chairman, presiding.
18 COMMITTEE MEMBERS:
19 JOSE MARCH-LEUBA, Chair 20 RONALD G. BALLINGER, Member 21 CHARLES H. BROWN, JR. Member 22 VESNA DIMITRIJEVIC, Member 23 GREG HALNON, Member 24 DAVID PETTI, Member 25 JOY L. REMPE, Member NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
2 1 ACRS CONSULTANT:
2 STEPHEN SCHULTZ 3
4 DESIGNATED FEDERAL OFFICIAL:
7 ALSO PRESENT:
8 SHAWN CAMPBELL, RES 9 JESUS DIAZ-QUIROZ, GEH 10 MICHAEL DUDEK, NRR 11 THOMAS GEORGE, Zachary Engineering 12 BERNARD GILLIGAN, GEH 13 SYED HAIDER, NRR 14 ROSEANNE HARRINGTON, GEH 15 DAVID HINDS, GEH 16 CHARLES HECK, GEH 17 ANDREW IRELAND, NRR 18 SCOTT KREPEL, NRR 19 NECDET KURUL, GEH 20 PETER LIEN, NRR 21 SHANLAI LU, NRR 22 JUN MATSUMOTO, GEH 23 RYAN NOLAN, NRR 24 DAN PAPPONE, GEH 25 LISA SCHICHLEIN, GEH NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
3 1 JAMES SHEA, NRR 2 JOE STAUDENMEIER, RES 3 CARL THURSTON, NRR 4 GEORGE WADKINS, GEH 5 FROSTIE WHITE, GEH 6
7 8
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4 1 CONTENT 2 Opening Remarks . . . . . . . . . . . . . . . . . 5 3 Discussion of GE-Hitachi Topical Report, 4 BWRX-300 Containment Evaluation Method . . . . 12 5 Staff's Evaluation of GE-Hitachi's 6 Topical Report . . . . . . . . . . . . . . . . . 40 7 Public Comment . . . . . . . . . . . . . . . . . 79 8
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5 1 P R O C E E D I N G S 2 (1:00 p.m.)
3 CHAIR MARCH-LEUBA: The meeting will now 4 come to order.
5 This is a meeting on the BWRX-300 ACRS 6 Subcommittee. I am Jose March-Leuba, the SC chairman.
7 Because of COVID-19 concerns, this meeting 8 is being conducted in a highly minded manner. In 9 addition to in-person attendance at NRC headquarters, 10 the meeting is broadcast via MS Meetings. Members in 11 attendance are Ron Ballinger, Charles Brown, David 12 Petti. And I haven't checked on the -- Vesna, are 13 you, are you in?
14 MEMBER DIMITRIJEVIC: Yes, I am.
15 CHAIR MARCH-LEUBA: Vesna Dimitrijevic is 16 present, too.
17 And we have Steve Schultz, our consultant.
18 Anybody I have missed?
19 MR. BROWN: Is Greg going to be in the 20 meeting?
21 CHAIR MARCH-LEUBA: When Greg shows up I 22 will put it on the record.
23 MR. BROWN: And Joy?
24 CHAIR MARCH-LEUBA: Today's topic is 25 Licensing Topic Report NEDC-33922P by General NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
6 1 Electric-Hitachi, BWRX-300 Containment Evaluation 2 Method. Portions of our meeting will be closed to the 3 public to protect GEH proprietary information.
4 We shall now receive the questions and 5 provide comments plus an opportunity for spur-of-the-6 moment public comments before the beginning of the 7 closed section of the meeting.
8 The ACRS was established by statute and is 9 governed by the Federal Advisory Committee Act, FACA.
10 As such, the committee can only speak to this 11 published letter report.
12 The rules for participation in all ACRS 13 meetings were announced in the Federal Register on 14 June 13th, 2019. The ACRS section of the U.S. NRC 15 public website provides our charter, bylaws, agendas, 16 letter reports, and full transcripts for the open 17 portions and all full and subcommittee meetings, 18 including the slides presented there.
19 The representative federal official today 20 is Mike Snodderly.
21 A transcript of the meeting is being kept.
22 So, speak into the microphones clearly, and state your 23 name for the benefit of the court reporter, especially 24 during the meeting using the bridge line. Please 25 leave the microphone on mute when not being used and NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
7 1 when you are speaking you have 15 minutes.
2 I note that members Greg Halnon and Joy 3 Rempe have joined us.
4 We are expecting to analyze this topic 5 during the full committee meeting on April 6th, and 6 possibly to write a letter.
7 At this point let's request Mr. Mike Dudek 8 from NRC to present his opening remarks.
9 Mike, are you ready?
10 MR. DUDEK: Yes, sir.
11 So, thank you, Subcommittee Chairman 12 March-Leuba. And thank you to the rest of the ACRS 13 subcommittee for allowing us to present this second 14 important topical report for GEH's BWRX-300 technology 15 today. Specifically, this one that we're discussing 16 this afternoon, as Subcommittee Chairman March-Leuba 17 said, is the BWRX-300 containment evaluation method 18 topical reports.
19 It was first submitted to the NRC in the 20 fall of 2020, and subsequently had three different 21 revisions submitted, up to and including January 7th, 22 2022. And the purpose of the topical report is to 23 really present the acceptable analysis methods for the 24 BWRX-300 containment and thermal hydraulic 25 performance, and demonstrate that the containment NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
8 1 designs satisfy the acceptance criteria outlined in 2 the topical report.
3 And more specifically, you know, 4 associated with that containment performance analysis, 5 it really outlines subject topic areas such as AOOs, 6 station blackouts, ATWS, Large and Small Break LOCAs, 7 and things of that nature.
8 The staff conducted a very in-depth review 9 on this topic report over a 2-year period, and 10 developed a very inclusive safety evaluation reports 11 in accordance with several rounds of RAIs and a very 12 in-depth and topic-specific audit that was discussed.
13 So, without any further ado, I will turn 14 it over back to you, Subcommittee Chairman March-15 Leuba, and I'll look forward to the discussions and 16 any questions that you have today.
17 CHAIR MARCH-LEUBA: Thank you.
18 We will, without any wait, we'll go to the 19 GE. I understand management wants to make, George 20 Wadkins will make some introductory remarks and you 21 will present your team.
22 I remind everybody we are in the open 23 portion of the meeting. And this topical report 24 contains proprietary information. So, reserve your 25 questions for an hour from now when we move to the NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
9 1 closed session.
2 George, go ahead.
3 MR. WADKINS: Thank you. My name is George 4 Wadkins. I am the Vice President of New Power Plants 5 and Products Licensing for GE-Hitachi.
6 I wish to thank the ACRS subcommittee for 7 allowing us to present the overview of the content for 8 this licensing topical report. Today we will be 9 describing the use of GOTHIC thermal hydraulics code 10 as the methodology to be used to verify that design 11 requirements for the BWRX-300 dry containment will be 12 met in the preliminary and final design of the BWRX-13 300.
14 This will include, for example, maximum 15 allowed containment, post-accident pressure and 16 temperature response.
17 As noted in our previous discussions with 18 the ACRS, the BWRX-300 builds upon our most recent 19 experiences in development and certification of the 20 Economic Simplified Boiling Water Reactor, or ESBWR.
21 One major difference between the ESBWR and 22 the BWRX-300 is in the functional design of the 23 containment. The ESBWR utilized a compartmentalized 24 containment with a dry well surrounding the reactor 25 and connected systems, including piping and vales, and NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
10 1 a wet well containing a suppression pool. The 2 suppression pool functions to condense steam from the 3 reactor, depressurization, and to allow passive 4 injection of water to maintain water inventory in 5 cooling of the reactor core, while maintaining 6 acceptably low containment pressures and temperatures.
7 The BWRX-300 has a relatively large, 8 relatively large dry containment that does not require 9 a wet well as a containment pressure and temperature 10 suppression feature, but it does include a passive 11 containment cooling system for heat removal from 12 containment.
13 Reactor depressurization is achieved 14 through use of the isolation condenser system instead 15 of through an automatic depressurization system that 16 releases steam to the suppression pool.
17 And the BWRX-300 does not require the more 18 complicated passive injection systems used in the 19 ESBWR design.
20 Because of the simplified design of the 21 containment, the analytical methods requirements are 22 also simplified, with the application of a different 23 methodology using GOTHIC instead of the traditional 24 TRACG code used for containment pressure and 25 temperature response for the ESBWR and other BWRs.
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11 1 This licensing topical report seeks 2 approval for use of GOTHIC as an acceptable code 3 methodology for the BWRX-300.
4 I first want to thank the NRC staff for 5 their in-depth review of this licensing topical 6 report. The interactions with the NRC's technical 7 staff, including the conduct of the audit, really 8 helped to ensure that the content of the licensing 9 topical report was complete, understandable, accurate, 10 and met the applicable regulatory requirements and 11 guidance.
12 I also wish to thank staff of the Canadian 13 Nuclear Safety Commission for their participation in 14 the joint review of this licensing topical report with 15 the NRC staff.
16 And I look forward to continuing this and 17 future interactions with the NRC staff, Canadian 18 Nuclear Safety Commission staff, and the ACRS.
19 Next slide, please.
20 So, for this meeting we are going to 21 provide an extensive open session discussion of the 22 content of this licensing topical report, as shown in 23 this agenda. This report also has a proprietary 24 version which will be discussed in the closed session 25 later, following this open session meeting.
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12 1 During our presentation we will pause at 2 the end of each slide to allow for questions from the 3 ACRS members. But please feel free to raise questions 4 at any time. If the discussions involve proprietary 5 information, then we will request tabling the 6 questions until the latter closed session.
7 Next slide, please.
8 I will now turn over the presentation to 9 Lisa Schichlein, U.S. Licensing Manager.
10 Thank you.
11 MS. SCHICHLEIN: Good afternoon. My name 12 is Lisa Schichlein, and I am the U.S. Licensing 13 Manager for New Power Plants and Products at GE-14 Hitachi Nuclear Energy Americas. I would like to 15 thank the ACRS subcommittee for the opportunity to 16 present the BWRX-300 containment evaluation method 17 licensing topical report.
18 With me on the call today are -- is the 19 licensing engineer Frostie White; consulting engineer 20 for nuclear applications Charles Heck; principal 21 engineer for containment Necdet Kurul; Dan Pappone, 22 the chief consulting engineer for plant performance; 23 David Hinds, principal engineer for plant integration; 24 Roseanne Harrington, manager of LOCA and containment 25 analysis; and Guangjun Li, technical lead for LOCA and NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
13 1 containment analysis.
2 In addition, we have Dr. Tom George, who 3 is a consultant from Zachary Engineering. And with us 4 today also are Bernard Gilligan and Jun Matsumoto from 5 Hitachi America Ltd.
6 As questions arise, I may direct the 7 questions to one or more of these individuals.
8 GEH is seeking NRC approval to apply an 9 analysis method for evaluating the dry containment 10 thermal hydraulic performance of the BWRX-300 small 11 modular reactor, using the TRACG and GOTHIC computer 12 codes.
13 The reason for this new method is because 14 the BWRX-300 has a dry containment. Therefore, we are 15 using a different code than we have used in the past 16 for reactor and containment thermal hydraulic 17 performance. Specifically, GOTHIC is now being used 18 with inputs from TRACG to evaluate thermal hydraulic 19 performance.
20 The scope of this topical report includes 21 a method description and qualification, sensitivity 22 studies, application of the method to the BWRX-300 for 23 the events identified earlier or discussed earlier, 24 and demonstration cases.
25 The analysis method used for the BWRX-300 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
14 1 containment thermal hydraulics performance 2 demonstrates that the containment design complies with 3 the following acceptance criteria, which are discussed 4 in more detail in Section 4.0 of the Topical report.
5 The containment pressure boundary and 6 penetrations are designed for the design pressure and 7 temperature to be established for design basis 8 accident in accordance with GDCs 2, 4, 16, 38, 41, 50, 9 and 51.
10 The containment design pressure will be 11 evaluated to bound the peak accident containment 12 pressure resulting from the most limiting large break 13 LOCA in accordance with GDCs 4, 16, 38, 41, 50, and 14 51.
15 The containment design features establish 16 an essentially leak-tight barrier, and will be 17 demonstrated to reduce containment pressure and 18 temperature rapidly, maintaining them at acceptably 19 low pressures following a LOCA, in accordance with 20 GDCs 16, 38, and 50.
21 The containment structure and its internal 22 compartments can accommodate, without exceeding the 23 design leakage rate and with sufficient margin, the 24 calculated pressure and temperature conditions 25 resulting from a LOCA in accordance with GDCs 16, 38, NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
15 1 and 50.
2 I would like to emphasize that GEH is not 3 seeking NRC approval for any exemptions from 4 regulatory requirements.
5 I want to close out this section by 6 restating that the methodology described in the 7 topical report complies with all applicable regulatory 8 requirements as written.
9 And GEH is not requesting NRC approval for 10 exemptions from any regulatory requirements.
11 CHAIR MARCH-LEUBA: Lisa, this is Jose.
12 Can you hear me?
13 MS. SCHICHLEIN: Yes. Yes, I can.
14 CHAIR MARCH-LEUBA: Yeah, because I opened 15 my mouth before and it wasn't working.
16 In Slide 5 I noticed that we are asking 17 for a 10 percent margin during the PSAR phase. That's 18 right in the middle of the slide, the bullet No. 2.
19 What do you mean by "during the PSAR phase"? It's not 20 for the licensed facility?
21 MS. SCHICHLEIN: I'm sorry. Frostie, would 22 you like to address that question?
23 MS. WHITE: I'm sorry if you can't hear me.
24 There's a terrible thunderstorm going on right now, 25 so.
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16 1 CHAIR MARCH-LEUBA: We can hear you.
2 MS. WHITE: We, when we first wrote this 3 section this was from when, as you said, two years 4 ago. And in that part of it we were in our 5 preliminary phrase. But this would be applicable 6 throughout the life of the plant.
7 CHAIR MARCH-LEUBA: Okay. So, it's just a 8 godfather sentence language.
9 MS. WHITE: Correct.
10 CHAIR MARCH-LEUBA: Thank you.
11 MR. WADKINS: Yes, this is George Wadkins.
12 I did want to explain.
13 The 10 percent margin in the PSAR stage is 14 actually a recommendation or a guideline within the 15 SRP. It is an initial margin which is established in 16 the old Part 50 process as the margin that you need to 17 have at preliminary design stage, which equates to the 18 PSAR stage for a construction permit application.
19 So, I just wanted to clearly state that.
20 We do not necessarily have to maintain a 10 percent 21 margin throughout the license of the plant. So, in 22 the operating license application with the final 23 safety analysis report that margin is not necessarily 24 a requirement.
25 CHAIR MARCH-LEUBA: Okay. I will ask the NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
17 1 staff to remember in your presentation to see if you 2 agree with this section. Okay? Thank you.
3 MS. SCHICHLEIN: Thank you.
4 Let's now move into the technical 5 evaluation.
6 Section 1.3 of the topical report contains 7 the acceptance criteria for the containment 8 performance.
9 The acceptance criteria include:
10 Accident pressure and temperature less 11 than the design pressure and temperature with an 12 appropriate margin:
13 Containment pressure reduced to less than 14 50 percent of the peak accident pressure for the most 15 limiting LOCA within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />; 16 For LOCAs that do not produce the peak 17 accident pressure, the containment pressure response 18 after 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is maintained below 50 percent of the 19 peak pressure for the most limiting LOCA; 20 And for the containment atmos -- and the 21 containment atmosphere remains sufficiently mixed such 22 that deflagration or detonation does not occur inside 23 containment.
24 The containment evaluation method 25 presented in the topical report is an acceptable NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
18 1 method to demonstrate that the above performance 2 design criteria are met.
3 CHAIR MARCH-LEUBA: Lisa, can you describe 4 in the open session what the containment atmosphere is 5 during operation?
6 MS. SCHICHLEIN: I would like to pass that 7 question off, please, to either Charlie Heck or Necdet 8 Kurul.
9 Either Charlie or Necdet, if you could 10 come off of mute and address that?
11 MR. HECK: Yeah, I think we can say here 12 that -- Go ahead, Necdet.
13 MR. KURUL: No. Yeah, please go ahead.
14 MR. HECK: All right. This is, it's not 15 proprietary, but this is inerted to containment.
16 CHAIR MARCH-LEUBA: Okay. Thank you. So, 17 until you reach separation it's because there is so 18 much inert gas, I will assume nitrogen, that there is 19 no oxygen, there is no oxygen to deflagrate. Correct?
20 MR. HECK: Correct. Or very, very limited 21 oxygen. Let's put it that way.
22 CHAIR MARCH-LEUBA: Yeah. But it's so 23 diluted with the nitrogen that hydrogen and oxygen 24 don't get to see each other.
25 Okay. Keep going.
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19 1 MS. SCHICHLEIN: The reactor pressure 2 vessel, including the isolation condenser, piping and 3 reactor isolation valves, are described in the NRC 4 approved topical report NEDC-33910P, "RPV Isolation 5 and Overpressure Protection."
6 The conceptual containment design, 7 penetrations, isolation valves, and Passive 8 Containment Cooling System, are described in the NRC 9 approved topical report NEDC-33911P, "Containment 10 Performance."
11 There are several containment design 12 features that are relevant to the containment 13 evaluation methodology.
14 The containment is a dry enclosure, and 15 near atmospheric pressure during normal operation.
16 It is also inerted with nitrogen during 17 normal operation.
18 And there are no subcompartments 19 containing large bore high energy lines.
20 And these subcompartments have 21 sufficiently large openings so the boundaries of the 22 subcompartments do not experience large pressure 23 differentials from pipe breaks outside of the 24 subcompartments.
25 Additionally, it should be noted that the NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
20 1 containment design, pressure, and temperature are 2 within the experience base of conventional BWRs.
3 Topical report Section 3 discusses the 4 loss of coolant accident scenarios evaluated and 5 limiting pipe breaks.
6 The limiting large pipe breaks evaluated 7 are the main steam pipe and feedwater pipe with all 8 large pipe breaks assumed to rapidly isolate at the 9 reactor pressure vessel nozzle.
10 For small breaks, the limiting small break 11 is an unisolated instrument line break.
12 Let's move into an overview of the 13 containment evaluation model.
14 The containment evaluation method involves 15 the use of two codes, TRACG and GOTHIC. TRACG is 16 specifically used to evaluate the mass and energy 17 release consistent with its use in evaluating mass and 18 energy release for the ESBWR.
19 This method has been previously approved 20 by the NRC as part of the ESBWR design certification.
21 GOTHIC is the code used to evaluate the 22 containment thermal hydraulic response, and uses a new 23 containment model developed for BWRX-300.
24 The GOTHIC code has been benchmarked to 25 separate effect and integral tests. Benchmarking to NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
21 1 the test data of a similar size containment is 2 included in the topical report.
3 The containment response evaluation method 4 for BWRX-300 uses both base and conservative cases.
5 For the conservative cases, key inputs, 6 assumptions, and modeling parameters are 7 simultaneously conservatively biased, which is the 8 same approach used and approved for ESBWR.
9 Section 5.0 of the topical report provides 10 details on the prior applications of TRACG.
11 The purpose of this section in the topical 12 report is to demonstrate that the previous TRACG code 13 qualification remains applicable to the BWRX-300.
14 The ESBWR TRACG LOCA method is applied to 15 the BWRX-300 mass and energy release calculations to 16 evaluate the large and small steam and feedwater pipe 17 break base and conservative cases. The following 18 bullets on this and the next slide outline the high-19 level content discussed in the topical report.
20 More specifically, the topical report 21 provides details on the modeling biases in the 22 Phenomena Identification and Ranking Table, or PIRT, 23 as well as details on the nodalization and the initial 24 conditions for the conservative cases.
25 To assist the NRC in their review of this NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
22 1 methodology, GEH performed both base and conservative 2 demonstration cases for the main steam and feedwater 3 large breaks, as well as for the small steam and 4 liquid pipe break cases.
5 GOTHIC then takes the output from the 6 TRACG mass energy release calculations to evaluate the 7 containment performance. Both base and conservative 8 cases were evaluated.
9 As is done with the TRACG mass and energy 10 release calculations, for the conservative cases the 11 individual key inputs, assumptions, and modeling 12 parameters are conservatively biased simultaneously, 13 This is the same approach taken for the ESBWR 14 containment method.
15 This next slide outlines the content 16 provided in the topical report detailing the 17 containment analysis method for the BWRX-300.
18 Section 6.0 of the topical report 19 identifies the relevant inputs and phenomena relevant 20 to the BWRX-300 containment response, and a selection 21 of the models and correlations used to develop the 22 base GOTHIC containment model.
23 It also includes the GOTHIC input model 24 for the BWRX-300 containment, as well as the base 25 cases and the results obtained from those base cases.
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23 1 It includes a discussion of how 2 nodalization impacts the calculated results.
3 There is also a discussion regarding which 4 GOTHIC model uncertainties and biases are most 5 important to the application of the GOTHIC model to 6 the BWRX-300 containment evaluation methodology; the 7 key model uncertainties and biases that are used in 8 developing the conservative GOTHIC containment model; 9 and the benchmark predictions of test data.
10 Section 6.0 of the topical report also 11 includes the large steam line break and small steam or 12 liquid break demonstration analyses showing the 13 containment response for various break sizes and 14 locations using the conservative GOTHIC containment 15 model.
16 There is also a summary of the assumptions 17 and inputs used in the GOTHIC conservative cases.
18 In conclusion, I would like to wrap up 19 this presentation by restating that the methodology 20 described in the licensing topical report complies 21 with all applicable regulatory requirements as 22 written.
23 GEH is not requesting NRC approval for 24 exemptions from any regulatory requirements.
25 The method uses two computer codes, TRACG NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
24 1 and GOTHIC.
2 TRACG uses the applicable parts of the 3 approved topical report for the application of TRACG 4 to ESBWR, which is incorporated in the approved ESBWR 5 design certification.
6 And GOTHIC is a standard industry code 7 used for thermal hydraulic containment evaluations in 8 the nuclear industry.
9 Within the methodology, individual key 10 inputs, assumptions, and modeling parameters are 11 conservatively biased simultaneously, which is the 12 same approach taken for the ESBWR containment method 13 in the NRC-approved topical report Report NEDC-33083 14 P-A, Revision 1, "TRACG Application for ESBWR."
15 I'd now like to ask for any questions or 16 comments for the GEH team.
17 CHAIR MARCH-LEUBA: Members, any comments 18 for GEH on the open session?
19 I don't see anything. Thank you very 20 much. Hold on.
21 Vesna, do you have any, any questions?
22 MEMBER DIMITRIJEVIC: No.
23 CHAIR MARCH-LEUBA: Thank you.
24 MR. SCHULTZ: I have a comment, Jose.
25 This is Steve Schultz. Lisa, a couple NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
25 1 just general questions.
2 In the staff presentation they indicate 3 that we've seen a couple of reports here now on the 4 containment evaluation, and also containment 5 performance. There's another report from GEH coming 6 in next on safety strategy.
7 Is there a nexus to the evaluations that 8 we've seen here on containment and safety strategy, or 9 is that something different? Just curiosity.
10 MS. SCHICHLEIN: I would like to have 11 George Wadkins address that question, please.
12 George, if you're able to comment?
13 MR. WADKINS: Yes. This is George Wadkins.
14 There is only a limited amount of 15 relationship between this and the safety strategy in 16 that the safety strategy will define the functional 17 safety functions that have to be met in the design as 18 far as defense-in-depth. And, obviously, the 19 containment function is one that we then design the 20 plant to.
21 So, the safety strategy will define those 22 defense lines necessary to meet the containment 23 functional safety function requirement. And then also 24 look at the postulated initiating events and sequences 25 for AOOs and DBAs and severe accidents in order to NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
26 1 establish when the containment function is required in 2 the transient analysis.
3 So, that is the connection. The safety 4 strategy establishes mainly functional requirements 5 for containment. And then the transient analyses that 6 are affected and required to be analyzed using the 7 functional requirements of the containment.
8 MR. SCHULTZ: Thank you, George.
9 And my next question is related, well, it 10 relates to what's coming up in the presentations by 11 the staff with respect to the limitations and 12 conditions that are proposed associated with their 13 review.
14 And in those limitations and conditions 15 the expectation is a requirement of either a 16 particular or specified design and performance 17 characteristic capabilities of the BWRX-300 design.
18 Can perhaps get the issues addressed with some 19 analysis demonstrations.
20 But are there any particular design 21 characteristics or changes that you would anticipate 22 as a result of a way to meet those limitations and 23 conditions in a generic fashion so that licensees in 24 the future don't have to address them? I presume with 25 the BWRX-300 SMR that you want to have one design that NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
27 1 you can apply across the customer base.
2 Is there any particular design features 3 that you are considering changing to address the 4 limitations and conditions?
5 MS. SCHICHLEIN: I'd like to see if Necdet, 6 would you like to speak to that?
7 MR. KURUL: Okay. This is Necdet Kurul, 8 GE-Hitachi.
9 Yes, there will be some designs to, design 10 development to address some of the limitations and 11 conditions. In terms of the isolation condenser 12 radiolytic gas removal, there is a specific design 13 being developed for that.
14 Also, isolation condenser return line 15 design limitation and condition No. 2, that 16 configuration is currently under development.
17 Limitation and condition No. 3, we do not 18 believe that it is going to require any design change.
19 Limitation and condition No. 4, there will 20 be some changes to passive containment cooling system.
21 But we believe that is going to make the analysis even 22 simpler than what is presented in this LTR, without 23 changing any of the phenomena.
24 MR. SCHULTZ: Thank you for the response.
25 I wanted to see that on the public record.
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28 1 Thank you.
2 CHAIR MARCH-LEUBA: And just for 3 clarification on public record, those will be part of 4 the final design. We are only reviewing now how the 5 methodologies work with or without them. Is that 6 correct? Basically, we're not assuming they have been 7 implemented, and we don't need to because we're 8 reviewing the methodology of how we will arise them in 9 the system.
10 MS. SCHICHLEIN: Correct.
11 MR. KURUL: That's correct.
12 CHAIR MARCH-LEUBA: Thank you.
13 Any more questions, including Vesna?
14 (No response.)
15 CHAIR MARCH-LEUBA: So, this ends the open 16 portion of the GE presentation. And we're going to 17 transfer to the staff. Now we will have the staff 18 presentation.
19 So, we're going to see the open session 20 for the staff.
21 So, I want to mention for the people that 22 are not present that it's a big milestone today. For 23 the first time in two years we have actual in-person 24 presenters in this room. We're very happy to see you.
25 And it is a new configuration. So, keep your NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
29 1 microphones on red unless you are talking. And when 2 you want to talk, put them on green.
3 So, and you are going to be sharing the 4 slides?
5 MR. SHEA: Yeah. I was just going to ask 6 permission, this is Jim Shea, I was going to ask 7 permission to share my slides, my screen.
8 Understand.
9 CHAIR MARCH-LEUBA: You're the presenter; 10 right?
11 MR. SHEA: Yes.
12 MR. DUDEK: Jim, Subcommittee Chairman 13 March-Leuba, I think Scott has some opening remarks as 14 the responsible branch chief, if we do have a minute?
15 CHAIR MARCH-LEUBA: We always have time for 16 that. Please go ahead.
17 MR. KREPEL: Can you hear me?
18 CHAIR MARCH-LEUBA: Yes, we can.
19 MR. KREPEL: Okay, hello. Hi. This is 20 Scott Krepel. I'm actually speaking through a sign 21 language interpreter.
22 I am the Branch Chief for the Lead 23 Technical Review Branch, Nuclear Systems Performance 24 Branch. This is a complex review with staff from four 25 different branches, as well as a novel coordinator NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
30 1 with the Canadian Regulatory Agency.
2 Some of you may recall that before I 3 became a branch chief I was a topical report reviewer.
4 I can say that I've seen comparable reviews take two 5 to three years, or even longer. The staff did a good 6 job of completing its review in just a little more 7 than one year, despite some unexpected challenges.
8 I would like to commend the GEH staff for 9 being very responsive to our questions and requests, 10 which was crucial to our ability to support this 11 schedule.
12 Thank you, everyone.
13 MEMBER REMPE: Well, I have a question.
14 I'd like to hear a little bit more about 15 what happened with the coordination with the Canadian 16 review. And I don't know if Scott or one of you could 17 answer what impact it had and how it progressed?
18 Be sure and state your name.
19 MR. LU: Shanlai Lu from staff. And I'm 20 Acting Branch Chief for Branch 7.
21 So, we do have the agreement signed off 22 between two agencies regarding the BWRX-300. And my 23 understanding is the Canadian has, you know, approach 24 and is in the process to review six BWRX-300 units.
25 So, their CNSC staff is working closely NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
31 1 with the NRC staff through the entire review process.
2 And we have, we shared all the proprietary information 3 between the GEH and CNSC. And so, actually they are 4 on this, too.
5 MEMBER REMPE: But, again, I'd like more 6 detail. Is it healthy? Is it taking longer? I 7 assume it will make it easier in the long run. But 8 are they, how do you do this? Will you divide it, 9 say, okay, you take?
10 MR. LU: Yes. You can see Mike Dudek is 11 the Licensing Branch, can talk to that.
12 CHAIR MARCH-LEUBA: Yeah. Mike wants to 13 talk to that.
14 MR. DUDEK: So, it's a very good question.
15 This was a joint effort in every way, shape, and form.
16 They actually, we actually split, swapped some staff 17 members. The NRC sent a staff member to go up, 18 virtually to go up to Canada and learn about their 19 process, procedures, and integrate with their staff 20 during their portions of the review.
21 And they had a staff member come down and 22 attend just about every working group session, and 23 every technical discussion, and every audit discussion 24 that we had on this.
25 So, with that being said, certain parts NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
32 1 weren't assigned to certain organizations; it was a 2 collaborative effort. You know, we, instead of 3 having, you know, a technical staff member sitting 4 down at a desk and doing the technical review solo, 5 you know, they would bring into a group atmosphere and 6 have a group discussion on some of those items. And 7 then they would jointly write it in the SharePoint 8 file, then have, and have that dialog and have those 9 discussions as they went.
10 So, it's a true joint effort in every way, 11 shape, and form. And we actually developed a joint 12 report that we're very, very close to bringing to 13 closure. I spoke to division management today and, 14 hopefully, going to ops management next week. And 15 hopefully out sometime in early August in which we 16 developed a lot of these thoughts to help explain how 17 we conducted the review, the things we found, some 18 mutual learnings, and some good taskings that we could 19 take back and use during both of our reviews when we 20 have the applications come to pass.
21 Does that answer your question, Chairman 22 Rempe?
23 MEMBER REMPE: Yes. I just am curious. I 24 apologize, but I can't help ask one more question.
25 Did you see that they had certain aspects NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
33 1 they were focused more on than the U.S. or vice versa?
2 Or is that too much to ask and I ought to just be 3 patient and wait for the report?
4 MR. DUDEK: So, a lot of that's outlined in 5 the report. They definitely have a different 6 perspective. I believe that the NRC's reviews are 7 more focused on the codes and running those 8 independent analyses. And I think that we learned a 9 lot about each other's regulatory structures and how 10 we do the reviews.
11 I think that can be summarized as the 12 majority of the learnings. So, very beneficial for 13 both parties to get that perspective.
14 MEMBER REMPE: Well, that's great. Send 15 the report when it's available to my staff and we can 16 distribute it to us. But I appreciate the time to 17 divert on this topic.
18 Thank you.
19 MR. DUDEK: Absolutely. And we hope to 20 have that report finalized and sent to you before the 21 full committee meeting. That's our goal.
22 MEMBER REMPE: Great.
23 CHAIR MARCH-LEUBA: Yes. We are going to 24 see within a week-and-a-half. Okay.
25 MR. SHEA: Just to have a slight add to NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
34 1 that. This is Jim Shea again, the project manager for 2 the BWRX-300 for the NRC staff.
3 Just that they participated in the audit 4 process. The audit went almost a full year. It was 5 every week we had a meeting. And number of issues, 6 approximately 45 issues that were resolved. Some 7 ended up in RAI space. But it was very extensive, and 8 the Canadians participated in that process.
9 Good afternoon. My name is Jim Shea.
10 Like I said, Office of Nuclear Reactor Regulation, the 11 Division of New and Renewed License, DNRL. I'm the 12 project manager for the GE BWRX-300 design licensing 13 topical report, and the lead project manager for the, 14 overall for the GEH BWRX-300.
15 I want to thank the ACRS full committee 16 for this time to allow the staff to present its review 17 of this licensing topical report as reflected in the 18 staff safety evaluation report which was submitted 19 publicly March 9th, 2020 in ADAMS.
20 The staff review focused on the approval 21 of the GEH BWRX-300 containment evaluation method.
22 You may see an acronym used: CEM. You'll see that's 23 Containment Evaluation Method. For the evaluation of 24 the design basis accidents as stated in the safety 25 evaluation report.
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35 1 The NRC staff will evaluate the compliance 2 of the final BWRX-300 SMR design, including the 3 containment evaluation method, during future licensing 4 activities in accordance with 10 C.F.R. Part 50 or 10 5 C.F.R. Part 52.
6 The LTR was submitted to NRC on September 7 25th, 2020. Revision 1 was supplemented with RAI 8 responses and was submitted to the NRC on November 9 19th. And additional Revision 2 was submitted 10 December 17th, 2021 11 I just want to go quickly as the lead TM 12 to look at our status in the big picture for pre-13 application activities.
14 You can see that during the presentation 15 the DEH and the NRC we referred back to some of these 16 LTRs that had been approved. You could almost look at 17 the approved containment performance as a precursor 18 for this LTR. They kind of fit together, the 19 requirements that were outlined and that became the 20 performance LTR are what are being addressed in this 21 LTR as far as the DBAs and criteria.
22 Two LTRs are currently under review, the 23 two that we had viewed today. And there's three more 24 expected this year. Sometime in June a safety 25 strategy methods that we talked about earlier, and a NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
36 1 severe accident management source term methodology 2 later. Also an instrumentation and controls 3 architecture will be coming out.
4 CHAIR MARCH-LEUBA: Jim, I always start my 5 questions with can you describe in open session what 6 the safety strategy LTR is about, high level? It was 7 mentioned earlier. I know what it is but I don't know 8 if it's proprietary.
9 MR. SHEA: Yeah, I don't believe it's 10 proprietary. I think GEH already kind of answered it.
11 They're looking at their safety strategy 12 method. It's taking the IAEA methodology for looking 13 at safety systems, really classification of safety 14 systems, and using that hierarchy, and seeing how this 15 reactor will fit into that hierarchy. Even though 16 they're still going to meet all of our, you know, our 17 regulations. But they're just taking that because 18 that, you know, for their, you know, the Canadians are 19 using that architecture for it.
20 CHAIR MARCH-LEUBA: My understanding, and 21 I haven't seen the topical, is they're going to align 22 the IAEA requirements with the NRC requirements.
23 Whatever is higher --
24 MR. DUDEK: Chairman March-Leuba, yes, I 25 would refer to maybe, perhaps, GEH to answer the NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
37 1 specifics behind their intent on these topical 2 reports. I would hate to speculate, since we haven't 3 seen, you know, in-depth details about what is 4 included in these, the NRC staff.
5 CHAIR MARCH-LEUBA: We will ask them in the 6 closed session.
7 MR. SHEA: Thanks, Mike.
8 I can refer to you there is some of that 9 discussed in the LTR that's already -- that has been 10 approved on the activity control. There is some 11 discussion about that criteria in the hierarchy that's 12 kind of confusing folks. But that's --
13 MR. BROWN: This is Charlie Brown. The 14 instrumentation control architecture, and don't take 15 this, my comments the wrong way, I'm saying this 16 talking. We first reviewed this, or I first reviewed 17 this back in 2009 for ESBWR. All right. And it was 18 difficult. The architecture is not well defined, very 19 little detail relative to what we've done in the rest 20 going up to APR-1000, NuScale, APR-1400.
21 But the last two went very, very smoothly 22 because it addressed what the committee's been looking 23 for: good architecture diagrams, good explanations of 24 control of access, independence, all the stuff that 25 goes into the fundamentals.
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38 1 Is this just going to be a repeat of the 2 ESBWR design? Because it took almost a year-and-a-3 half or two to finally get any change of I&C or 4 manager.
5 MR. SHEA: I think, I think that what Mike 6 said is accurate. We don't really know at this stage.
7 They haven't been submitted.
8 But I think GEH is listening. So, I think 9 they probably took your comment.
10 MR. WADKINS: Yes. This is George Wadkins 11 from GEH.
12 I understand your comment. We are, we are 13 going to follow on with the more later applications, 14 including the NuScale application approach. So, we 15 believe that we will be able to hit the mark based on 16 the more current approval of I&C architecture.
17 MR. BROWN: Okay. That will be excellent.
18 Thank you. Makes it very, very easy when that 19 architecture is well defined, including the definition 20 of one-way hardware-based non-software configured 21 communication devices in a network, et cetera.
22 So, does that --
23 MR. LU: This is Shanlai Lu. Thanks for 24 the comments.
25 I think this, for the purpose of today's NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
39 1 presentation. It's a part of this topical report is 2 the continuing methodology. Whether we hear that one 3 --
4 MR. BROWN: I'm just trying to make sure.
5 MR. LU: Yes.
6 MR. BROWN: So, early understanding of what 7 we might be expecting.
8 MR. LU: Got it.
9 MR. BROWN: At least what the committee's 10 going to be expecting to be able to do.
11 MR. LU: Got it. We got it.
12 MR. BROWN: That would be helpful instead 13 of waiting for six months to say that's not --
14 MR. LU: I agree. We all agree. We all 15 agree with that.
16 MR. BROWN: All right. Thank you. I will 17 stop.
18 CHAIR MARCH-LEUBA: Shanlai, you might 19 start thinking that maybe we wasted 10 minutes on 20 this. But this is very useful for the membership, 21 good to know what's coming and that there are labor --
22 MR. LU: Yes.
23 CHAIR MARCH-LEUBA: -- and we have a lot of 24 work. Thank you. Thank you for that.
25 MR. SHEA: Okay, thank you. And we will NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
40 1 get back to the task at hand.
2 And the next slide we have the NRC staff 3 review team. And I'll turn it over to Syed Haider, 4 who is the lead reviewer for this, for this LTR.
5 MR. HAIDER: Thank you, Jim.
6 Good afternoon to everyone. My name is 7 Syed Haider. I'm the lead reviewer on the GEH 8 licensing topical report LTR NEDC-33922P on BWRX-300 9 containment evaluation method, which is mainly related 10 to modeling the containment pressure and temperature 11 response that were reserved from the limiting design 12 base events involving mass energy leaks from the 13 reactor pressure vessel into the containment for the 14 BWRX-300 SMR design.
15 My Nuclear Systems Performance Branch at 16 NRR had the lead for the review under Branch Chief 17 Scott Krepel; Jim Shea, the NRR New Reactor Licensing 18 Branch GPM.
19 Carl Thurston and Shanlai Lu from NRR's 20 Nuclear Methods, Systems & New Reactors Branch were 21 the reviewers of the LTR part related to the TRACG 22 modeling and mass energy release calculation 23 methodology, that is covered under Section 5.0 of the 24 safety regulation report.
25 I, myself, mainly reviewed the GOTHIC NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
41 1 modeling and containment pressure and temperature 2 response calculation methodology that's covered under 3 Section 6.0 of the SER.
4 Chang Li from Containment and Plant 5 Systems Branch reviewed combustible gas, gases inside 6 the containment. Throughout the review the NRR staff 7 was supported by the research staff that includes 8 Peter Lien, Joe Staudenmeier, and Andrew Ireland from 9 the Code and Reactor Analysis Branch, and Shawn 10 Campbell from the Fuel & Source Term Code Development 11 Branch.
12 The staff were responsible for the 13 development of the TRACE and confirmatory models that 14 were used to analyze and relegate the TRACG and GOTHIC 15 model reserves. And terms presented in the LTR we can 16 provide those details during the closed session.
17 Next slide, please.
18 This slide shows the outline of the 19 current open staff presentation during which we will 20 avoid discussing any proprietary information. That 21 will be covered during the closed session later.
22 First, the staff will give an overview of 23 the intended purpose and scope of the BWRX-300 LTR.
24 It's worth mentioning here that even though the LTR 25 title is BWRX-300 containment evaluation method, the NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
42 1 LTR covers the methodology and modeling details for 2 both the BWRX containment as well as the operating 3 site.
4 First I'll go with the BWRX-300 5 containment design background that drives the code of 6 the presented methodology.
7 We will review the components of the BWRX-8 300 design as they relate to the TRACG and GOTHIC code 9 based RTV and containment analysis methodologies with 10 the eventual objective to predict the containment 11 thermal hydraulic response with sufficient concept 12 data.
13 In this regard, we will explain the 14 regulatory requirements and BWRX-300 acceptance 15 criteria for the containment response underlying the 16 LTR and how they relate to the present safety 17 evaluation for the design basis accidents.
18 Then I will give a summary of the BWRX-300 19 containment evaluation method, demonstration and 20 analyses that I presented in the LTR.
21 After these introductory slides, my NRR 22 colleague Carl Thurston will present a few slides on 23 the TRACG code based mass energy release calculation 24 methodology review. After that, I'll present a few 25 slides on our GOTHIC code based containment response NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
43 1 calculation methodology.
2 The detailed technical research for the 3 TRACG is mass energy methodology, and GOTHIC is 4 containment response methodology, are proprietary and 5 will be presented during the closed session.
6 Again, Carl and I will describe the full 7 conditions and limitations on the LTR as they emerged 8 during the staff review of the LTR.
9 Then we will finish the presentation of 10 the staff reviews.
11 Next slide, please.
12 This slide describes the scope of the 13 BWRX-300 containment evolution methodology LTR as 14 reviewed by the staff. Basically GE-Hitachi has 15 submitted this LTR to obtain the NRC staff's approval 16 of the overall BWRX-300 containment peak pressure and 17 temperature analysis methodology, as presented in the 18 LTR.
19 The NRC regulations and acceptance 20 criteria that deal with the BWRX-300 containment 21 thermal hydraulics performance are listed in a 22 separate GE-Hitachi licensing topical report on BWRX-23 300 containment performance. That was presented to 24 ACRS last year.
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44 1 will be used to perform the BWRX-300 containment 2 safety analysis to support either a licensing 3 application for a construction permit and operating 4 license under 10 C.F.R. Part 50, or a design 5 certification and combined license application under 6 10 C.F.R. Part 52.
7 Next slide, please.
8 So, I now will summarize the state-of-the-9 art of the BWRX-300 containment design and its 10 relation with the current staff review and the 11 methodology. And this slide just presents the salient 12 design features of the BWRX-300 containment that are 13 relevant to the containment safety analysis 14 methodology for the design basis accidents.
15 These design features drive several 16 initial and conditions in the containment GOTHIC 17 model. So, basically BWRX-300 has a dry containment 18 that's inerted with nitrogen during normal operation.
19 It does not have a suppression pool inside 20 the containment like ESBWR had.
21 This information is relevant to initial 22 containment pressurization and the post-accident 23 mixing of steam and radiolytic gases inside the 24 containment.
25 A key design feature of the BWRX-300 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
45 1 design is the early closure of its RPV isolation valve 2 that limits the mass and energy release into the 3 containment during the large break LOCA which dictates 4 the peak containment pressure.
5 However, the RPV isolation valve does not 6 close for small breaks that remain unisolated 7 resulting in a continuous break flow for the small 8 break LOCA analysis period.
9 And the BWRX-300 design employs a passive 10 containment cooling system, or PCCS, that's used to 11 remove heat from the containment reactor cavity pool 12 that's located above the containment. PCCS plays an 13 important role in the long-term containment pressure 14 reduction and mitigation.
15 In this regard, the LTR demonstration 16 analyses were performed with the specific PCCS design 17 unit described in the LTR. The reactor cavity pool 18 that's used by the PCCS for containment located above 19 the containment.
20 So --
21 MEMBER HALNON: I have a quick question.
22 This is Greg.
23 Small break LOCA, as I mentioned, there 24 was an instrument line.
25 MEMBER HALNON: -- the limiting break?
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46 1 MR. HAIDER: Limiting break for small 2 break LOCA.
3 MEMBER HALNON: It is a limiting break?
4 MR. HAIDER: Yeah.
5 MEMBER HALNON: You're talking about half 6 inch, quarter inch? What's the instrument line size?
7 (Simultaneous speaking.)
8 MEMBER HALNON: Sorry.
9 CHAIR MARCH-LEUBA: Yeah, let me remind 10 everybody of the new rule. The microphones are really 11 good for the people that are outside of the room. But 12 they don't amplify anything inside of the room. So 13 please speak. When you speak into the -- when you 14 talk into speaker -- microphone, people outside the 15 room hears you very well but we don't. So, like, 16 we're not hearing you.
17 MEMBER HALNON: Soft spoken. Got it.
18 MR. HAIDER: So the staff has performed 19 this review with a clear understanding that the BWRX-20 300 design is not final yet. And the analysis 21 presented in the LTR are demonstration cases. The 22 objective of the present review is to evaluate the 23 applicability of the methodology, the BWRX-300 design, 24 and access the degree of conservatism.
25 This has required the staff to focus on NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
47 1 the uncertainty and the methodology and predicted 2 trends without getting unduly exact numbers. The 3 staff has the understanding that the input and output 4 numbers may vary in the final design. That would be 5 submitted in the licensing stage.
6 So the overriding question the staff 7 resolved was how to approve the evaluation methodology 8 even if the BWRX-300 or similar design has not been 9 evaluated. Next slide, please. This slide highlights 10 the four acceptance criteria for containment response 11 used in the methodology. These acceptance criteria 12 are identified in the LTR for the BWRX-300 design 13 safety analysis and are essentially driven by several 14 NRC regulation.
15 This slide also captures two key 16 regulatory requirements for the containment safety 17 analyses that deliver the short term peak containment 18 pressure and temperature and the long term pressure 19 and temperature response of the containment. One key 20 regulatory requirement that is rooted in GDC 16 and 50 21 of 10 CFR, R50, Appendix C is to ensure that the peak 22 containment pressure and maximum wall temperature 23 calculated for the limiting mass-energy release design 24 basis accidents are bounded by the BWRX-300 design, 25 pressure, and temperature of its sufficient margin.
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48 1 I believe the question that was raised 2 during the presentation by GEH was about the 10 3 percent. The 10 percent margin is an interpretation 4 of SRP Section 6.2.1.1.A. All of them were sufficient 5 to use in GDC 50.
6 So GDC 50 requires sufficient (audio 7 interference). SRP Section 6.2.1 interprets it as 10 8 percent. So it's a guidance. It's not a regulation.
9 It's not a requirement.
10 CHAIR MARCH-LEUBA: The 10 percent really 11 didn't confuse me as much. It could be 8, could be 12 12. What confused me is that it applies to the 13 preliminary SAR and doesn't apply afterwards. That's 14 what I thought George Wadkins said and certainly what 15 the slide implied. So the sufficient margin would 16 apply to the final design.
17 MR. HAIDER: That's right.
18 CHAIR MARCH-LEUBA: And we will have to 19 agree whether 10 percent is sufficient or not.
20 MR. HAIDER: Correct. That's right.
21 CHAIR MARCH-LEUBA: All right. So when we 22 have a final design, you will come back here and tell 23 us what sufficient is. Thank you.
24 MR. HAIDER: Yeah, one more clarification 25 that I would like to make here is that the word, NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
49 1 margin, exactly is not relevant to this review. The 2 correct word is conservatism. The staff focused on 3 the conservatism. The margin when it comes up in the 4 design is final. That would be the difference between 5 the final design attributes and the limiting 6 conservative results.
7 CHAIR MARCH-LEUBA: Yeah, I can see your 8 point.
9 MR. HAIDER: So the second key regulatory 10 requirement is driven by GDC 38 of 10 CFR Part 50 11 Appendix A for containment heat removal that is 12 interpreted by the standard review plan as to ensure 13 that the containment pressure is reduced to less than 14 50 percent of the peak pressure for the most limiting 15 LOCA within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. So that is for a long term 16 pressure response. GDC 38 also requires that the 17 containment pressures 24 hours after LOCA is 18 maintained below 50 percent of the peak pressure for 19 the most limiting LOCA.
20 So not only the depressurization should 21 get the containment to less than 50 percent in 24 22 hours2.546296e-4 days <br />0.00611 hours <br />3.637566e-5 weeks <br />8.371e-6 months <br />, the pressure should as remain low, that the 23 mitigation can be interpreted. So essentially the 24 first three acceptance criteria, GDC 50, 16, and 38 25 that we have described, collectively ensure that the NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
50 1 containment structure can accommodate the pressure and 2 temperature condition exerting from any mass and 3 energy release from the RPV without exceeding the 4 design decay rate and it's sufficient margin. The 5 full acceptance criterion requires that the 6 containment atmosphere remains sufficient mixed so 7 that the deflagration or degradation does not operate 8 inside the containment.
9 CHAIR MARCH-LEUBA: Using GOTHIC, can we 10 estimate mixing? Or is that based on first 11 principles? I don't see how GOTHIC predict that the 12 atmosphere remains sufficient mixed, do you?
13 MR. HAIDER: They have covered 14 benchmarking that I was going to talk later, CVTR.
15 And that has certification. And the benchmark showed 16 benchmarking of GOTHIC code against the certification 17 for the CVTR.
18 CHAIR MARCH-LEUBA: Also, you're saying 19 that GOTHIC is actually qualified to identify 20 certification?
21 MR. HAIDER: That is my understanding.
22 And that's also the information they have included.
23 Next slide, please. So the LTR presents the 24 methodology demonstration in L&Cs and reserved for 25 evaluating the BWRX-300 containment and hydraulic NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
51 1 performance against the acceptance criteria for the 2 limiting design basis accident. In this backdrop, the 3 LTR presented alerts for large-break loss of coolant 4 accident and small-break loss of coolant accident 5 inside the containment.
6 The containment design basis analysis 7 presented in the LTR include both liquid and steam 8 breaks. This shows that the four acceptance criteria 9 were satisfied for the demonstration of cases.
10 However, the applicant would have to demonstrate 11 meeting the acceptance criteria for the final BWRX-300 12 design at the licensing stage while meeting the four 13 conditions and limitations the staff has imposed on 14 the LTR at the start of this review.
15 As mentioned earlier, the methodology uses 16 TRACG code to calculate mass-energy release from the 17 RPV into the containment. And GOTHIC code is used to 18 calculating exerting containment response. The LTR 19 provides the TRACG later detailed in Section 5 and 20 GOTHIC detailed in Section 6 of the LTR. And now I 21 will ask my NRR colleague, Carl Thurston, to present 22 the public summary of the TRACG modeling of the mass-23 energy release for BWRX-300 containment.
24 MR. THURSTON: So my name is Carl 25 Thurston, and I am the primary reviewer for the TRACG NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
52 1 code calculation of M&E releases. The TRACG code has 2 a long history of review by NRC staff to disable 3 previous topical reports submitted, including ESBWR, 4 ESBWR, and the existing fleet of BWR 2 to 6 reactors.
5 For review of the code, the staff focused its review 6 on code changes made since ESBWR.
7 And staff basically determined that there 8 were no significant changes since the analysis was 9 completed for ESBWR. The RPV model and internal 10 components were essentially scaled from ESBWR. The 11 methodology uses a decouple method so that the 12 containment is maintained at atmospheric pressure 13 throughout the full event, whether it's a small break 14 or a shorter time -- or excuse me, large break for a 15 shorter break or a small break for up to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
16 The containment --
17 (Simultaneous speaking.)
18 CHAIR MARCH-LEUBA: So there is no 19 feedback from GOTHIC back into TRACG?
20 MR. THURSTON: That's correct.
21 CHAIR MARCH-LEUBA: And that is 22 conservative because we estimate a larger flow --
23 MR. THURSTON: That's correct.
24 CHAIR MARCH-LEUBA: -- out of the vessel?
25 MR. THURSTON: That's correct. The NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
53 1 methodology relies heavily upon previous TRACG topical 2 reports and their compatibility with BWRX-300, 3 particularly for the ESBWR qualification. So the 4 ESBWR qualifications extended to BWRX-300 such that 5 ESBWR PIRT and model biases apply directly to the RPV 6 and internals.
7 In addition, the BWR/2 through 6 methods 8 were invoked because there were some events where core 9 uncover results and you need a more detailed model to 10 resolve the phenomenon. The isolation condensers have 11 a significantly more important safety function than 12 was used for ESBWR. And so it's modeled in 13 considerably more detail for the BWRX-300. Staff 14 determined that the modeling was adequate for M&E 15 release calculations with consideration of the limits 16 and conditions being applied. Next slide.
17 CHAIR MARCH-LEUBA: Oh, of particular 18 concern, everybody will tell you -- you will tell us.
19 Is the presence of non-condensable isolation 20 condenser? How will this TRACG model non-condensable 21 gases?
22 MR. THURSTON: My understanding is that 23 TRACG can model non-condensable gases within the code.
24 And we'll get into this more in our proprietary 25 session.
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54 1 CHAIR MARCH-LEUBA: Okay. We'll wait --
2 (Simultaneous speaking.)
3 MR. THURSTON: That was the reasons why 4 they did include it. So the next slide focuses on 5 unique features. And I think this has been covered 6 and fairly detailed already. But the larger breaks 7 are all isolated by valves that are mounted on the 8 nozzles of the RPV that close quickly so that any 9 release from a larger break is limited.
10 There's no suppression pool. And the 11 isolation condensers are the primary. They are the 12 only mechanism of decay heat removal for this plant.
13 RPV isolation valves limits break flow and mass 14 release indicated.
15 But the small breaks are un-isolated and 16 continue to blowdown for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. For this analysis, 17 one of the trains of ICS was considered inoperative 18 due to single failure. The determined that 19 conservative inputs were used for initial power, power 20 history, scram, choke flow model, and the fact that 21 they used atmospheric boundary condition. And in 22 addition, the operating conditions also were 23 conservative. Next slide.
24 So there were two key issues that the 25 staff found and related to the TRACG calculation of NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
55 1 mass and energy release. The first one is related to 2 accumulation of radiolytic gases and the isolation 3 condenser. The staff looked at the methodology that 4 was used by GEH and did not feel the gases were 5 appropriately modeled.
6 The staff did confirmatory analysis that 7 we will show in a closed session. So those gases that 8 can be generated in the reactor can transport to the 9 isolation condensers. And if they get there, they 10 will heat transfer and the isolation condensers are 11 not able to perform as rated.
12 CHAIR MARCH-LEUBA: And the most direct 13 pass is a return line, not the forward line?
14 MR. THURSTON: So both passes are 15 potentially allowing radiolytic gases to get to the 16 IC, whether it goes to the steam line or through the 17 return line.
18 CHAIR MARCH-LEUBA: And the solution with 19 this recommendation, they will talk more detail in the 20 closed session. It's to either license better it 21 better or fix it.
22 MR. THURSTON: Yeah, so we will get into 23 that.
24 CHAIR MARCH-LEUBA: Yeah, we'll wait.
25 MR. THURSTON: So as we indicated, the NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
56 1 non-condensable gases will build up in a lower drum.
2 And that degrades the heat transfers. It can 3 significantly degrade heat transfer in isolation 4 condensers.
5 The second issue that the staff found and 6 write an RAI about is related to the design of the 7 return line. So for the ESBWR, the return line was 8 discharged into the downcomer. And for this plant 9 design, if I'm going too far, GEH will correct me, it 10 discharges into the chimney region which is a slightly 11 higher pressure.
12 So it increases the likelihood that steam 13 can back flow into the return line and again make it 14 to the isolation condenser and in effect heat transfer 15 in the isolation condenser. So that's the first and 16 second limited conditions. The next slide --
17 (Simultaneous speaking.)
18 CHAIR MARCH-LEUBA: Is the concern that 19 steam will go through the back flow through the return 20 line or non-condenser?
21 MR. THURSTON: Steam and non-condensers 22 will be in the steam. And when it condenses --
23 (Simultaneous speaking.)
24 CHAIR MARCH-LEUBA: But the following will 25 be the -- I mean, if more steam makes it to the ICS, NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
57 1 it's working better. ICS works like condensing steam.
2 The more steam you put up there, the more liquid 3 you're sending down.
4 MR. THURSTON: That's right.
5 CHAIR MARCH-LEUBA: The problem will be 6 the non-condensable --
7 (Simultaneous speaking.)
8 MR. HAIDER: Hi, this is Syed Haider back 9 to cover the GOTHIC and containment slide of the 10 review. This slide presents an overview of the GOTHIC 11 code as reviewed by the staff of the BWRX-300 12 containment response and the LTR application for the 13 NRC approval. GOTHIC code is an established computer 14 code that has been widely used in the industry for 15 containment response analysis.
16 This is a continuously improved code that 17 is compliant with the pertinent NRC regulation, 10 CFR 18 Part 50, Appendix B. GEH has used the latest GOTHIC 19 version 8.3 of the BWRX-300 analysis demonstrated in 20 the LTR. During the order, GEH clarified that they 21 followed the relevant analysis process should there be 22 a need to use a different GOTHIC version for the final 23 design of the licensing stage.
24 As far as the GOTHIC based applications in 25 the past are concerned, GOTHIC code has been NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
58 1 previously approved by NRC for containment response 2 analyses. The staff also reviewed BWRX-300 3 containment PIRT method phenomenology and found it 4 covered by the available GOTHIC functionalities. The 5 staff also reviewed the GOTHIC benchmarking against 6 the CVTR test data that the LTR presented for the 7 BWRX-300 containment methodology qualification.
8 The information provided in the LTR and 9 RAI responses demonstrated that GOTHIC is qualified 10 for the thermal stratification and 3D effects. These 11 features are important for the nodalization-based 12 containment design approach of distributed PCCS units.
13 Next slide, please. This slide captures the key 14 features of the GOTHIC model development under 15 containment response calculation methodology and the 16 LTR.
17 The evaluation method for the BWRX-300 18 containment response for design basis accident has 19 been developed following the applicability of Reg 20 Guide 1.203 that is used to establish an acceptability 21 evaluation method and analyze transient nuclear power 22 plant responses during the postulated design basis 23 accidents. Reg Guide describes a multi-step process 24 for developing evaluation models for assessing well 25 defined figures of merit. The BWRX-300 containment NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
59 1 evaluation methodologies based on decoupled 2 calculation between TRACG and GOTHIC where TRACG RPV 3 model calculate the mass-energy release into the 4 containment assuming it remains the same initial 5 atmospheric pressure throughout the accident duration.
6 That means that the TRACG RPV model mass-energy 7 release calculations do not account for the increasing 8 containment backpressure.
9 We're using the decoupled approach. The 10 standalone GOTHIC containment model independently uses 11 the mass energy release calculated by TRACG as a 12 containment boundary condition to calculate the 13 containment pressure and temperature response. The 14 staff agrees that this ensures a conservative mass-15 energy release into the containment with respect to 16 containment pressure and temperature response. As 17 described in the LTR, the containment evaluation 18 method is based on four component GOTHIC model that 19 include a nodalized mean component of containment, a 20 nodalized dome, a nodalized PCCS, and a lumped reactor 21 cavity pool in aerospace.
22 A Conservative Diffusion Layer Model, DLM, 23 is used and justified for modeling condensation heat 24 transfer on the containment shell and PCCS surface.
25 The option for condensation built into GOTHIC to NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
60 1 calculate the condensation rate is based on a 2 mechanistic model of the underlying phenomena which is 3 based on heat and mass transfer analogy. A 4 nodalization-based modeling of fluids accounts for the 5 thermal stratification inside the containment. Next 6 slide, please.
7 This slide summarizes the staff review of 8 the BWRX-300 GOTHIC containment response methodology.
9 More information will be provided about these events 10 during the closed session. The staff reviewed the 11 applicability of the important physical phenomena 12 identified by the GOTHIC PIRT table for the BWRX-300 13 design and found them appropriate.
14 The applicants submitted GOTHIC decks 15 based on conservative cases for both big and small 16 break LOCAs, we reviewed the GOTHIC input model and 17 used the submitted GOTHIC decks to gather information 18 to develop the TRACE and MELCOR decks for confirmatory 19 analyses. Key modeling and uncertainties and 20 conservative biases were reviewed to establish the 21 overall GOTHIC model conservatism. We'll review and 22 we'll provide more information about the nodalization 23 sensitivity studies for the containment and PCCS 24 during the closed session. We also reviewed the LTR 25 benchmarking of the GOTHIC code against the CVTR test NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
61 1 data and the justification for bounding the 2 containment, condensation, and natural convection heat 3 transfer correlations by using the coping (phonetic) 4 test data.
5 The staff also made sure that the BWRX-300 6 containment response analyses do account for 7 appropriate break location and break flow direction 8 sensitivities. The staff also reviewed the PCCS 9 capacity to reduce and mitigate the containment 10 pressure in the long-term, identifying a small un-11 isolated liquid break as a potential limiting small 12 break LOCA. Containment mixing was also reviewed with 13 respect to combustible gasses accumulation inside the 14 containment. The staff also performed confirmatory 15 analyses to develop necessary insights during the 16 review.
17 CHAIR MARCH-LEUBA: I've seen the 18 proprietary version of this. And you kind of put the 19 confirmatory analyses at the end as bullet number 10.
20 And it was a pretty significant effort. I wanted to 21 emphasize in the open session that there was a 22 significant effort by the staff to do confirmatories.
23 And I confirmed that if it works.
24 MEMBER REMPE: And I don't know what you 25 can say in the open session. But can you saw the NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
62 1 tools that you used? It's in the SE. Is that not 2 allowed to say what codes or methods you used --
3 (Simultaneous speaking.)
4 MR. HAIDER: You mean the confirmatory --
5 MEMBER REMPE: Analysis was done with?
6 MR. HAIDER: Was with TRACE and MELCOR 7 codes.
8 MEMBER REMPE: Yeah, I just would like to 9 have that.
10 MR. HAIDER: Yeah, TRACE and MELCOR codes 11 were used to develop the confirmatory model. Yeah, it 12 was a significant part. And that complimented our 13 staff because significant insights came from the 14 confirmatory analysis that the research conducted 15 throughout.
16 MEMBER REMPE: Thank you. I just would 17 like to have it in the open.
18 CHAIR MARCH-LEUBA: Yeah, while we're on 19 the record -- you found a key point. It's not the 20 confirmatory analysis per se. It's the inside of the 21 staff review and the design that you obtain by having 22 to do the confirmatory. That provides significant 23 value. That insight is what's invaluable.
24 MR. HAIDER: That's true. That's very 25 true. Thanks for highlighting that. Next slide, NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
63 1 please. This slide gives a summary of the key 2 technical issues that the staff encountered on the 3 containment side of the review. We will present the 4 needed technical details of the issues resolution and 5 the supporting confirmatory analysis (audio 6 interference) are during the closed session.
7 The already submitted Rev 0 of the LTR and 8 not performed any break location or break flow 9 direction studies -- sensitivity study. The staff 10 will elaborate on its concerns about the limiting 11 break location and flow orientation during the closed 12 session. The staff also noticed that limiting a small 13 break was a steam break LOCA in the LTR who had no 14 containment analysis was performed for this small 15 liquid break LOCA.
16 So RAI is where it should and their 17 response showed sensitivity to the break location and 18 break flow direction. We've modified the limiting 19 large break location and break flow orientation. It 20 responds also -- showed that a liquid rather than a 21 steam break while the limiting small break LOCA with 22 respect to peak containment pressure.
23 The staff had noticed that even though the 24 applicant had presented a containment and nodalization 25 study for large break LOCA but with four different NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
64 1 nodalization schemes. Non-light sensitivity study was 2 performed for the small break in the original 3 submittal. So an RAI was issued and a small break 4 LOCA nodalization study revealed that even though the 5 peak containment pressure was sensitive to the 6 nodalization of the scheme, it was always smaller than 7 the limiting peak containment pressure that occurs 8 during the large break LOCA for the containment design 9 and used in the demonstration analyses.
10 It was also observed that the sensitivity 11 to small break LOCA nodalization diminished in the 12 long-term response. However, the deck point, the 13 applicant try to go around the containment pressure 14 response by using the limiting RPV pressure response 15 in a quasi-best estimate fashion. Those details will 16 be provided in the closed session.
17 However, using the limiting RPV and 18 containment pressure for SBLOCA for the long term 19 containment response evaluation raises a distinct 20 possibility of break flow reversal on containment 21 break to the RPV with non-condensable gases on the 22 containment entering the RPV and degrading the 23 isolation condenser. This has led to the development 24 of limitation and condition number 3 that essentially 25 requires that the BWRX-300 final design has to be NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
65 1 demonstrated for no safety significant break flow 2 reversal. This will be further discussed during the 3 closed session.
4 CHAIR MARCH-LEUBA: Let me stop you right 5 there because this is key. Because if you generate 6 radiolytic gases inside the vessel, hydrogen, and you 7 can recombine it with oxygen and get rid of it. But 8 if you input a lot of nitrogen into the vessel, there 9 is nothing you can do short of bending it.
10 So when we have a final design, we will 11 expect you to look at this design and make sure no 12 reverse flow happens with sufficient confidence. I'm 13 certain (audio interference) know everything. But 14 allowing a lot of nitrogen into the vessel is bad for 15 this design. You know that.
16 MR. HAIDER: Yes, that's correct. That 17 was the prime mover on limitation and condition number 18 3. So this will be -- of the condensation and natural 19 convection heat transfer biases used in the model, and 20 significant differences between the GOTHIC of 21 predicted dome and PCCS heat transfers in the 22 confirmatory analysis.
23 The applicant deep dived into the GOTHIC 24 decks and also identified a major error in the PCCS 25 condensation heat transfer modeling. This was a NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
66 1 significant correction to a large number of plots in 2 the LTR that left to the revision of an LTR revision 3 -- one LTR revision. We'll provide further details of 4 the error and the resolution in the closed session.
5 The staff also showed an RAI on the PCCS 6 modeling and performed a PCCS confirmatory study to 7 validate the PCCS sensitivity study presented in the 8 LTR. More detail will be provide about these staff 9 concerns and their disposition. In the RAI, the 10 applicant did mention that even though they have 11 presented the demonstration cases with a specific PCCS 12 configuration.
13 And they may use a different PCCS 14 configuration for the final design. In this regard, 15 the staff has introduced limitation and condition 16 number 4 for the applicability to the final PCCS 17 design for licensing basis. Now I'll ask Carl 18 Thurston to describe the two RPV-specific limitations 19 and conditions that we attached.
20 MR. THURSTON: Thank you, Syed. So now 21 we'll basically just review those two limit and 22 condition. I think we described them I think in 23 fairly good detail already. If there's any questions, 24 I think we can address those.
25 But the first one is related to the NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
67 1 accident, if the normal steam going into the isolation 2 condenser can accumulate, it degrades the 3 effectiveness of the isolation condenser. And again, 4 because the isolation condenser is the primary path of 5 decay heat removal, it has to function correctly and 6 at the rate it conditions. The next limit and 7 conditions are related to the return line.
8 And again, the main emphasis is to prevent 9 the flow of radiolytic acids back to the isolation 10 condenser and not disrupting the flow. Also there's 11 reverse flow, it can affect the amount of flow that's 12 going to the -- back through the lines. So the line 13 has to flow efficiently to keep the whole cycle 14 working. So that's the reason for limit and condition 15 number 2. So I'll turn it back over to you, Syed.
16 CHAIR MARCH-LEUBA: Before you move to the 17 next, the 72-hour period in my opinion is a leftover 18 from active large lightwater plants where LOCA and 19 ECCS failure was dependent on loss of power. And we 20 decided 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> was sufficient long enough to restore 21 it. Now here we have passive plants. Does the 72-22 hour still make sense or do we need to make a week, a 23 month?
24 MR. THURSTON: So we are still using the 25 72-hour as an analysis. Maybe I can turn it over to NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
68 1 Shanlai Lu. It's been our guidance and our practice.
2 I don't know if it's codified how we apply it 3 directly. So Shanlai can clarify that question.
4 MR. HAIDER: Can I offer my comment? Syed 5 here. I engaged GEH on this specific issue of 72 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and the applicability of the methodology through 7 an RAI and also through audit discussions. Their 8 outlook pretty much was that this methodology is 9 driven by, in part, phenomena identification table.
10 So their position was that as long the 11 phenomenology remains applicable and doesn't change 12 for any reason, they believe that the methodology 13 should or could be extended beyond 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. So the 14 acceptance criterion is the applicability of the 15 phenomenon rather than the 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> deadline.
16 CHAIR MARCH-LEUBA: I understand why 17 you're saying that. Today we're talking about the SER 18 on this topical report which is a methodology. My 19 question -- and I apologize. I maybe should have ask 20 it today or maybe I should ask it two years from now.
21 If we survive -- if the X-300 design 22 survives for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> and we know it's on trend that 23 it's going to fail in two hours later or two weeks 24 later, would that be accepted? And this is a bridge 25 we'll have to cross two years from now when we review NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
69 1 the X-300. As of today, we're looking at the 2 methodology -- and what you say is correct, the 3 methodology -- is applicable here.
4 That's what we're concluding today. But 5 keep thinking forward. ACRS wrote a letter saying 6 that transients in passive plans have to be analyzed 7 all the way to when you reach a stable condition, 8 whether it's 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, or 150 hours0.00174 days <br />0.0417 hours <br />2.480159e-4 weeks <br />5.7075e-5 months <br />.
9 If you are continuously degrading and 10 getting into a less safe condition, you should not 11 artificially stop at 72. That's our position and 12 maybe go against regulation. But certainly the logic 13 tells us that's what one should do.
14 MEMBER REMPE: On the other hand, it's for 15 mitigating actions could occur which should be within 16 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. And the fact that it's still not a stable 17 state, I'm not sure your logic holds.
18 CHAIR MARCH-LEUBA: No, what I'm saying 19 you have analyze it.
20 MEMBER REMPE: But if they want longer 21 than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, yeah, it ought to be longer. But if 22 you can say, I can get my --
23 (Simultaneous speaking.)
24 CHAIR MARCH-LEUBA: I'm not against 25 getting credit for mitigation actions past 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
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70 1 MEMBER REMPE: Okay.
2 CHAIR MARCH-LEUBA: You don't have any 3 Class 1E power. But you are going to get power in 72 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
5 MEMBER REMPE: Yeah, and that was the 6 reason. So I was having trouble following your logic.
7 But if you want longer for mitigating strategies to be 8 implemented, then I get what you're saying. But 9 anyhow, I just had to --
10 MR. SHEA: Actually, it's kind of 11 interesting because I researched this extensively. I 12 was -- anybody on the phone?
13 MR. NOLAN: Yeah, this is Ryan Nolan from 14 the staff. I was going to try to add some context.
15 But go ahead, Jim. You go first.
16 MR. SHEA: Okay. I was looking at this 17 myself because I was curious on the 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. And 18 it's not really in any regulation. And when I was 19 thinking about it, there's a lot of other things come 20 into play when you're talking about events, including 21 RTNSS. And so when you get the whole design and they 22 talk about all the mitigation that's going to come to 23 play, including then mitigating strategies.
24 For a design basis case, it's a specific 25 thing. It's artificial in a way. And that's what NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
71 1 they have to do to meet these LOCA regulations in the 2 DBA. So that's what kind of comes into play in my 3 mind.
4 CHAIR MARCH-LEUBA: Let me say something 5 before you go. We have a tendency of concentrating a 6 lot because that's what we do on Chapter 15 design 7 basis events. My comment was more related to Chapter 8 19, low probability events.
9 And we kind of tend not to think about 10 those for some reason simply because we always do 11 Chapter 15. That's what our job is. That's how we've 12 been doing all this life. And we need to think beyond 13 Chapter 15. I think Shanlai wanted to say something 14 or Joe.
15 MR. STAUDENMEIER: Yeah, I was going to 16 say the history --
17 CHAIR MARCH-LEUBA: Your name?
18 MR. STAUDENMEIER: Joe Staudenmeier. The 19 history of that 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, it was something that came 20 up with some utility requirements that EPRI put 21 together something saying for the passive plants, 22 like, the first two were ESBWR and they peak at 600.
23 And the Commission endorsed those requirements at the 24 time saying, yes, these are good things to meet. But 25 they're not really regulation. But it was guidelines NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
72 1 that the passive plants would have to survive for 72 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />.
3 CHAIR MARCH-LEUBA: As I said before, it's 4 not relevant to what we're discussing today. But it 5 will become eventually.
6 MR. NOLAN: Yeah, so this is Ryan Nolan 7 with the staff. I'll just add that when we do receive 8 an application, the Commission policy not only is it 9 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> with no operator actions. But it's also cope 10 onsite for 7 days for all design basis events.
11 And so the staff will look at a minute a 12 7-day period of time. You just get additional 13 flexibility under the regulatory treatment of non-14 safety system policies for what systems you can use 15 and what quality those systems need to be post 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> and post-7 days. And so, yeah, we agree with 17 you. You have to remain in a safe stable condition.
18 It's just after 72 hours, there's 19 additional flexibility for what you're allowed to use 20 in your analysis. And whether that analysis 21 ultimately ends up in Chapter 15 or 19, that's a 22 virtual cost when we get the application. But it's 23 certainly something we'll be looking at.
24 MR. LU: I think Ryan has already covered 25 that one specifically. So it will be handled by NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
73 1 Chapter 19 specifically, the partition between PRA 2 branch and the reactor system branch. But the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> 3 as Joe mentioned, it was initially proposed by EPRI 4 and endorsed by the Commission with the SRM for 72 5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />. But I think that Ryan mentioned that we are in 6 alignment with ACRS for the long term mitigation 7 beyond the 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> and the readiness program there.
8 But it will be reviewed by Chapter 19.
9 CHAIR MARCH-LEUBA: Okay. Thank you to 10 staff for this discussion.
11 MEMBER HALNON: Yeah, and this is Greg.
12 For the record, that covers my question on the small 13 break LOCA. I will hold it till Chapter 15 and 19.
14 CHAIR MARCH-LEUBA: I don't see any raised 15 hands. So let's continue.
16 MEMBER DIMITRIJEVIC: I just also want to 17 mention that in Chapter 19, simply the mission time 18 for the large release is 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. That changed 19 simply just for the new plans from 44. And I couldn't 20 find the base for the change. I mean, I was trying to 21 see how that change occurred from 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to 72. But 22 what Joy said, this is after 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. You can apply 23 different mitigation measures.
24 CHAIR MARCH-LEUBA: Thank you, Vesna.
25 MR. HAIDER: This is Syed Haider back.
NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
74 1 This slide provides the two containment specific 2 limitations and conditions number 3 and 4 that the 3 staff imposed as a result of the staff review.
4 According to the limitation and condition number 3 as 5 mentioned earlier in the presentation, limitation and 6 condition number 3 merged out of the potential 7 degradation of the isolation condenser heat transfer 8 performance should there be a reverse flow with one 9 condenser from the containment to the RPV.
10 Such a flow could take place if PCCS is 11 not properly sized to deal with the most limiting flow 12 reversal condition. Therefore, the licensing stage, 13 the applicant will need to demonstrate that either no 14 reverse flow would occur or any reverse flow that 15 occurs under the most bounding flow reversal 16 conditions is not safety-significant with respect to 17 the methodologies acceptance criteria. Regarding 18 limitation and condition number 4 requires that if any 19 alternate PCCS design configuration and placement is 20 used for the BWRX-300 design and the licensing basis 21 stayed other than the one presented in this LTR, the 22 applicability of this method. And the PCCS modeling 23 approach would have to be review and approved by the 24 NRC.
25 CHAIR MARCH-LEUBA: I made the same NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
75 1 comment earlier this morning, but you guys were not 2 here. On safety evaluation reports, language makes a 3 difference. And there is a difference between the 4 word review and the word audited.
5 So if your intention is to audit the new 6 PCCS, that means you have an approval to keep using 7 TRACG-GOTHIC for this analysis unless we find 8 something wrong. If you say, it must be reviewed and 9 approved, it kind of implies that you must issue a new 10 SER or a revision of the SER for the new PCCS. What 11 is your intent?
12 MR. HAIDER: The intent is a review.
13 CHAIR MARCH-LEUBA: Review and approve 14 means you must issue an SER. And you can review it in 15 an audit in which case it's by exception. You have 16 approval to do it unless we tell you otherwise.
17 But if you say must be reviewed and 18 approved, you don't have approval to do it until we 19 send you documentation that you can. So language 20 makes a difference. And you need to find out what is 21 it that you are going to do.
22 MR. HAIDER: Okay. I think we can 23 probably discuss some of the detail that might be 24 relevant.
25 CHAIR MARCH-LEUBA: I'm just putting it in NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
76 1 your brain so you understand the difference between 2 you are approved to do it unless we tell you otherwise 3 versus you cannot do it until I give you documentation 4 that you can. It's a big difference.
5 MR. HAIDER: Okay.
6 MEMBER REMPE: Am I hearing that you have 7 already or you're already aware of this difference and 8 you want to review it? Or you want to think about it 9 more?
10 MR. HAIDER: The language that we have 11 crafted in the limitation and condition number 4 is 12 review and approve.
13 MEMBER REMPE: And that's what you want.
14 MR. HAIDER: I'm not willing to discuss 15 the design details. They have commented on what kind 16 of changes they might be implementing in the PCCS 17 design.
18 CHAIR MARCH-LEUBA: My concern, I'm always 19 thinking what can possibly go wrong. We might be 20 making our life difficult by using the wrong wording 21 because a safety evaluation report has -- I mean, it's 22 not low. But the language has weight. You must 23 define.
24 MR. SHEA: This is Jim Shea again. I 25 think the key to all these LTRs is that there will be NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
77 1 a final review -- a staff review for a licensing 2 action. These aren't licensing actions. They're pre-3 application LTRs that we're using as a means to 4 approve, like in this case, a methodology.
5 And the methodology would be used no 6 matter what the PCCS final design is and that's what 7 we're saying. But however, like Syed said, he would 8 open that up to an audit to see that the methodology 9 is still applying to that newer design and overall 10 that the SE for the final licensing action would be 11 the closure.
12 MEMBER REMPE: So to make sure I 13 understand, you're saying if they put it in a 14 construction permit or a Part 52 type of application 15 that the final review and approval will be the staff 16 SE on that.
17 MR. SHEA: Correct.
18 MEMBER REMPE: Okay.
19 MR. SHEA: Yeah.
20 MR. HAIDER: Okay. Thank you. Now 21 finally we will present the staff conclusions for our 22 LTR review. In summary, the proposed BWRX-300 23 analytical approach, and the TRACG and GOTHIC modeling 24 of mass-energy release and containment response are 25 acceptable with the appropriate conservative biases NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
78 1 demonstrated in the LTR. With the four Limitations 2 and Conditions as specified in the staff SER, the 3 analysis method presented in the LTR Revision 2 is 4 acceptable for BWRX-300 containment pressure and 5 temperature analysis of the design basis accidents.
6 The NRC staff will be required to evaluate 7 the regulatory compliance of the final BWRX-300 8 containment design using the containment evaluation 9 methodology during the future licensing activities, in 10 accordance with 10 CFR Part 50 or 10 CFR Part 52, as 11 applicable to the application. And this concludes our 12 presentation. Thank you very much for attending. Now 13 the staff would like to address any additional 14 questions the Committee still might have.
15 CHAIR MARCH-LEUBA: And in spite of all my 16 best efforts, we are still on time. So we do have 17 time for a couple of questions. If the members or 18 Vesna want to ask anything from the staff?
19 (Simultaneous speaking.)
20 CHAIR MARCH-LEUBA: Anything else? Vesna, 21 you said I don't?
22 MEMBER DIMITRIJEVIC: Yeah, I said I'm 23 good.
24 CHAIR MARCH-LEUBA: Thank you. I don't 25 see any questions from the staff. I am going to open NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
79 1 the floor for public comments. So at this point, I 2 would like to open the session to comments from the 3 public.
4 You are attending the MSTeams. Just 5 unmute yourself. If you're calling on the bridgeline, 6 unmute via *6. Just a reminder that this is an 7 opportunity to add comments to the public record for 8 Committee consideration.
9 If you have any questions or particular 10 requests, please address them directly to our DFO, 11 Mike Snodderly. His email is 12 michael.snodderly@nrc.gov. Any public comments, 13 please say your name and give us your comments.
14 (No audible response.)
15 CHAIR MARCH-LEUBA: I don't hear anybody.
16 So at this point, we're going to recess for 15 minutes 17 until 3:00 o'clock Eastern and in which case we will 18 start the closed session. So anybody that belongs in 19 the closed session has a link.
20 Please call as soon as possible so the 21 staff and GEH can confirm that you can join. And this 22 always takes some time. So I will recommend that you 23 join the session now, put yourself on mute, and take 24 the break after that. So we will reconvene on the 25 closed session at 3:00 o'clock Eastern Time in 15 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
80 1 minutes. This meeting is recessed and we will not be 2 going back to this line.
3 (Whereupon, the above-entitled matter went 4 off the record at 2:45 p.m.)
5 6
7 8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1716 14th STREET, N.W., SUITE 200 (202) 234-4433 WASHINGTON, D.C. 20009-4309 www.nealrgross.com
GE Hitachi Nuclear Energy George E. Wadkins GE-Hitachi Nuclear Energy Americas, LLC Vice President, New Power Plants and Products Licensing 3901 Castle Hayne Road Wilmington, NC 28402 USA T 910.200.3295 George.Wadkins@ge.com M220009 March 9, 2022 U.S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555-0001 Canadian Nuclear Safety Commission 280 Slater Street P.O. Box 1046, Station B Ottawa, Ontario, K1P 5S9, Canada
Subject:
ACRS Subcommittee Open Session Presentation Slides for NEDC-33922P, BWRX-300 Containment Evaluation Method Licensing Topical Report Enclosed are the final presentation slides that GE Hitachi Nuclear Energy (GEH) will present during the Open Session at the upcoming Advisory Committee on Reactor Safeguards (ACRS) subcommittee meeting on March 18, 2022. These slides support the ACRS review of NEDC-33922P Revision 2, BWRX-300 Containment Evaluation Method, and the corresponding Advanced Safety Evaluation Report (SER) with No Open Items. contains non-proprietary information and may be made available to the public.
If you have any questions, please contact me at 910-200-3295.
Sincerely, George E. Wadkins Vice President, New Power Plants and Products Licensing GE-Hitachi Nuclear Energy Americas, LLC
Enclosure:
- 1. ACRS Subcommittee Open Session Presentation Slides for NEDC-33922P, BWRX-300 Containment Evaluation Method Licensing Topical Report - Non-Proprietary Information
M220009 Page 2 of 2 Document Components:
001 M220009 Cover Letter.pdf 002 M220009 Enclosure 1 Non-Proprietary.pdf cc: James Shea, US NRC Chantal Morin, CNSC PLM Specification 006N9430 Revision 0
ENCLOSURE 1 M220009 ACRS Subcommittee Open Session Presentation Slides for NEDC-33922P, BWRX-300 Containment Evaluation Method Licensing Topical Report Non-Proprietary Information
ACRS Subcommittee Presentation GE-Hitachi (GEH)
Licensing Topical Report (LTR) NEDC-33922P BWRX-300 Containment Evaluation Method (Open Session)
March 18, 2022
Agenda
- Licensing Topical Report Purpose and Scope
- Acceptance Criteria for Containment Evaluation Method
- RPV and Containment Features Pertinent to the Method
- LOCA Scenarios and Limiting Pipe Breaks
- Overview of the Evaluation Model
- TRACG Method for Mass and Energy Release
- Containment Analysis Method Using GOTHIC Copyright 2022 GE Hitachi Nuclear Energy Americas, LLC - All Rights Reserved 2
Licensing Topical Report Purpose and Scope LTR Purpose and Scope (LTR Section 1.1)
GEH is seeking NRC approval for application of an analysis method to be used for evaluating the BWRX-300 dry containment thermal hydraulic performance.
The LTR scope includes:
- Method description
- Method qualification
- Sensitivity studies
- Application of the method to the BWRX-300 for the events identified above
LTR Purpose and Scope (LTR Section 1.1)
The analysis method to be used for the BWRX-300 containment thermal hydraulics performance demonstrates that the containment design complies with the following acceptance criteria listed in Section 4.0 of Licensing Topical Report (LTR) NEDC-33911P, BWRX-300 Containment Performance:
- The containment pressure boundary and penetrations are designed for the design pressure and temperature to be established for design basis accidents (DBAs) during future licensing activities in accordance with 10 CFR 50, Appendix A, General Design Criteria (GDC) 2, 4, 16, 38, 41, 50, and 51.
- In accordance with 10 CFR 50, Appendix A, GDC 4, 16, 38, 41, 50, and 51, containment design pressure will be evaluated during future licensing activities to bound the peak accident containment pressure resulting from the most limiting large break loss-of-coolant accident (LOCA) with margin, with no less than 10%
margin during the preliminary safety analysis report (PSAR) phase in order to conform to Standard Review Plan (SRP) 6.2.1.1.A Acceptance Criteria.
- In accordance with 10 CFR 50, Appendix A, GDC 16, 38, and 50, the BWRX-300 containment design features establish an essentially leak-tight barrier, and will be demonstrated during future licensing activities to reduce containment pressure and temperature rapidly, and maintains them at acceptably low levels following a LOCA; and the containment structure and its internal compartments can accommodate, without exceeding the design leakage rate and with sufficient margin, the calculated pressure and temperature conditions resulting from a LOCA.
Copyright 2022 GE Hitachi Nuclear Energy Americas, LLC - All Rights Reserved 5
LTR Purpose and Scope (LTR Section 1.1)
- The methodology described in the LTR complies with all applicable regulatory requirements as written.
- GEH is not requesting NRC approval for exemptions from any regulatory requirements.
Copyright 2022 GE Hitachi Nuclear Energy Americas, LLC - All Rights Reserved 6
Technical Evaluation Containment Design Acceptance Criteria (LTR Section 1.3)
- Accident pressure and temperature are less than design pressure and temperature with appropriate margin
- Containment pressure is reduced to less than 50% of the peak accident pressure for the most limiting LOCA within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />
- Containment pressure responses after 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> for LOCAs that do not produce the peak accident pressure are maintained below 50% of the peak pressure for the most limiting LOCA
- Containment atmosphere remains sufficiently mixed such that deflagration or detonation does not occur inside containment The containment evaluation method presented in the topical report is an acceptable method to demonstrate that the above performance design criteria are met.
Copyright 2022 GE Hitachi Nuclear Energy Americas, LLC - All Rights Reserved 8
Relevant RPV and Containment Design Features (LTR Section 2.0)
The RPV, including the isolation condenser, piping and RPV isolation valves, are described in NEDC-33910P, RPV Isolation and Overpressure Protection Conceptual containment design, penetrations, isolation valves, and Passive Containment Cooling System (PCCS) are described in NEDC-33911P, Containment Performance The following containment design features are relevant to the purposes of the LTR:
- Containment is a dry enclosure, near atmospheric pressure during normal operation
- Containment design pressure and temperature are within the experience base of conventional BWRs
- Containment is inerted with nitrogen during normal operation
- There are no subcompartments containing large bore high energy lines
- The subcompartments have sufficiently large openings such that the boundaries of the subcompartments do not experience large pressure differentials resulting from pipe breaks outside the subcompartments Copyright 2022 GE Hitachi Nuclear Energy Americas, LLC - All Rights Reserved 9
LOCA Scenarios and Limiting Pipe Breaks (LTR Section 3.0)
- All large bore piping attached to the RPV has 2 isolation valves. The RPV isolation valves, except for those on the IC piping, close on either of the following conditions:
- High drywell pressure
- Low-low RPV water level
- An assumed single failure rendering an ICS train inoperative is the most limiting single failure for small breaks because the small breaks rely on ICS to depressurize the RPV.
- The limiting large breaks are:
- Main steam pipe
- Feedwater pipe
- All design basis large breaks are rapidly isolated at the RPV nozzle.
- The limiting small breaks are unisolated instrument line breaks, either in the steam or liquid space.
Copyright 2022 GE Hitachi Nuclear Energy Americas, LLC - All Rights Reserved 10
Overview of the Evaluation Model Overview of the Evaluation Model (LTR Section 4.0)
TRACG is used to evaluate the mass and energy release from the BWRX-300 RPV
- Utilizes applicable parts of TRACG Application for ESBWR approved LTR, which is incorporated in the approved ESBWR Design Certification
GOTHIC is used to evaluate the BWRX-300 containment response
- New containment model developed for BWRX-300
- Based on GOTHIC computer code - meets 10 CFR 50 Appendix B QA requirements
- The GOTHIC code has been benchmarked to separate effect and integral tests. Benchmarking to the test data of a similar size containment is included in the LTR.
Evaluation method for the BWRX-300 containment response to design basis events developed per the applicable elements of RG 1.203.
- Uses base and conservative cases
- Individual key inputs, assumptions and modeling parameters conservatively biased simultaneously in the conservative cases (same approach taken for the ESBWR containment method in NEDC-33903P-A Revision 1, TRACG Application for ESBWR)
- Evaluation method described in LTR Section 6.0.
Copyright 2022 GE Hitachi Nuclear Energy Americas, LLC - All Rights Reserved 12
TRACG Method for Mass and Energy Release (LTR Section 5.0)
- TRACG Code and Qualification (LTR Section 5.1)
- TRACG is the GE Hitachi Nuclear (GEH) proprietary version of the Transient Reactor Analysis Code (TRAC).
- TRACG uses realistic 1D and 3D models and numerical methods to simulate phenomena that are experienced in the operation of boiling water reactors (BWRs)
- TRACG ECCS-LOCA analysis method for BWR/2-6 and for ESBWR have been approved previously.
- The uncertainties in the TRACG ECCS-LOCA analysis methods are quantified for the BWR/2-6 and for ESBWR
- Only the uncertainties relating to RPV inventory and break flow are accounted for in the BWRX-300 application Copyright 2022 GE Hitachi Nuclear Energy Americas, LLC - All Rights Reserved 13
TRACG Method for Mass and Energy Release (LTR Section 5.0)
- Applies the ESBWR TRACG-LOCA method to the BWRX-300 mass and energy release calculations (LTR Section 5.2)
- The main steam piping of both loops up to the turbine stop valves are included in the model, and a large steam pipe break flow includes the flow from both ends of the break conservatively assuming instantaneous separation of the pipes.
- Channel Grouping, Decay Heat, and Power Shape (LTR Section 5.2.3)
- Modeling of the Isolation Condenser and Radiolytic Gases (LTR Section 5.2.4)
- Modeling Biases (PIRTs) (LTR Section 5.2.5)
- Conservative biases (LTR Table 5-1) are used to bound uncertainties in key TRACG models
- For conservative cases, the initial operating conditions are also conservatively biased (LTR Table 5-4)
- Initial Conditions for Conservative Cases: Trips and Isolation Signals bound the time required to reach the analytical setpoint, signal development time, and the time required for valve stem travel until the area restriction starts to occur. (LTR Section 5.2.6)
Copyright 2022 GE Hitachi Nuclear Energy Americas, LLC - All Rights Reserved 14
TRACG Method for Mass and Energy Release (LTR Section 5.0)
GEH performed both base and conservative demonstration cases:
- Demonstration Cases (Base and Conservative) for Main Steam and Feedwater Large Breaks (LTR Sections 5.3, 5.3.1, 5.3.2)
- Demonstration Cases (Base and Conservative) for Small Steam and Liquid Pipe Break Cases (LTR Section 5.4)
Copyright 2022 GE Hitachi Nuclear Energy Americas, LLC - All Rights Reserved 15
Containment Analysis Method Using GOTHIC (LTR Section 6.0)
The GOTHIC application methodology includes base cases and conservative cases.
- Base Cases:
- Nominal inputs, assumptions, and correlations
- Conservative Cases:
- Individual key inputs, assumptions and modeling parameters are conservatively biased simultaneously
- This method compounds conservatisms and provides reasonable assurance that the overall method results bound the uncertainties.
- This is the same approach that was taken for the ESBWR containment method.
Copyright 2022 GE Hitachi Nuclear Energy Americas, LLC - All Rights Reserved 16
Details of Containment Analysis Method Using GOTHIC (LTR Section 6.0)
- Identification of the relevant inputs and phenomena relevant to the BWRX-300 containment response and the selection of the models and correlations used to develop the base GOTHIC containment model (LTR Sections 6.1 - 6.4)
- Base cases and the results obtained from those base cases (LTR Section 6.6)
- How nodalization impacts the calculated results (LTR Section 6.7)
- Which model uncertainties and biases of the GOTHIC methodology are most important for application of the GOTHIC model for analyses of the BWRX-300 containment (LTR Sections 6.5 through 6.7)
- Key model uncertainties and biases used in developing the conservative GOTHIC containment model (LTR Section 6.8)
- Benchmark predictions of test data (LTR Section 6.9)
- Demonstration analyses showing the BWRX-300 containment response for various break sizes and locations using the conservative GOTHIC containment model (LTR Section 6.10)
- Large steam line break (LTR Section 6.10.1)
- Small steam or liquid breaks (LTR Section 6.10.2)
Copyright 2022 GE Hitachi Nuclear Energy Americas, LLC - All Rights Reserved 17
Conclusion In summary
- The methodology described in the LTR complies with all applicable regulatory requirements as written.
- GEH is not requesting NRC approval for exemptions from any regulatory requirements.
- TRACG utilizes the applicable parts of the TRACG Application for ESBWR approved LTR, which is incorporated in the approved ESBWR Design Certification
- Utilizes GOTHIC, a standard code used for evaluating thermal-hydraulic containment response in the nuclear industry
- Individual key inputs, assumptions and modeling parameters conservatively biased simultaneously in the conservative cases (same approach taken for the ESBWR containment method)
Copyright 2022 GE Hitachi Nuclear Energy Americas, LLC - All Rights Reserved 18
Questions or Comments Regulatory Review of GEH Topical Report BWRX-300 Containment Evaluation Method NEDC-33922P, Revision 2 NRC Staff Presentation-Open Session BWRX-300 Small Modular Reactor ACRS Subcommittee Meeting March 18, 2021 1
We make SAFE use of nuclear technology POSSIBLE.
GEH BWRX-300 Pre-Application Status
- September 26, 2019 - BWRX-300 Pre-Application Kick of Meeting
- 3 LTRs have been approved Reactivity Control LTR (NEDC-33912P) (04/01/21)
Reactor Pressure Vessel Isolation and Overpressure Protection LTR (NEDC-33910P) (08/16/21)
Containment Performance LTR (NEDC-33911P) (01/07/22)
- 2 LTRs currently under review Containment Evaluation Method LTR (NEDC-33922P) (AFSE 2/18/22)
Advanced Civil Construction and Design Approach LTR (NEDC-33914P) (AFSE 2/18/22)
- 3 LTRs expected in 2022 Safety Strategy (NEDC-33934P) 2Q22 Severe Accident Management and Source Term Methodology (NEDC-33913P) 3Q22 Instrumentation and Controls Architecture (NEDC-33925P) 3Q22 2
We make SAFE use of nuclear technology POSSIBLE.
NRC Staff Review Team
- NRR Nuclear Systems Performance Branch (SNSB)
- NRR New Reactor Licensing Branch (NRLB)
- NRR Nuclear Methods, Systems & New Reactors Branch (SNRB)
- NRR Containment and Plant Systems Branch (SCPB)
- Chang Li
- RES Code and Reactor Analysis Branch (CRAB)
- Peter Lien, Joe Staudenmeier, Andrew Ireland
- RES Fuel & Source Term Code Development Branch (FSTCB)
- Shawn Campbell 3
We make SAFE use of nuclear technology POSSIBLE.
Presentation Outline
- Overview of BWRX-300 Containment Evaluation Method (CEM) LTR NEDC-33922P, Revision 2
- BWRX-300 containment design background
- Regulatory requirements & BWRX-300 acceptance criteria for containment response
- BWRX-300 containment evaluation method demonstration analyses
- TRACG mass and energy release calculation methodology review
- GOTHIC containment response calculation methodology review
- Resulting four limitations and conditions
- Conclusions 4
We make SAFE use of nuclear technology POSSIBLE.
NRC Staff Review of the LTR
- The purpose of GEH LTR NEDC-33922P, Revision 2, is to obtain NRC staff approval of the BWRX-300 containment peak pressure and temperature analysis methodology.
- The NRC regulations and acceptance criteria dealing with the BWRX-300 containment thermal hydraulics performance are referenced in GEH LTR NEDC-33911P, BWRX-300 Containment Performance.
- The approved methodology will be used to design the BWRX-300 containment and support a license application for a CP and OL under 10 CFR 50 or a DCA and COL under 10 CFR 52.
5 We make SAFE use of nuclear technology POSSIBLE.
BWRX-300 Containment Design Background
- BWRX-300 has a nitrogen-inerted, dry containment
- No suppression pool inside the containment
- Passive Containment Cooling System (PCCS)
Long-term containment SBLOCA pressure mitigation Demo with specific LTR described units
- Reactor cavity pool for containment heat removal
- Containment dome interfacing with the reactor cavity pool 6
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Regulatory Requirements & BWRX-300 Acceptance Criteria for Containment Response
- Key Regulatory Requirements Short term peak containment pressure/temperature Long term pressure/temperature
- BWRX-300 LTR Acceptance Criteria Accident pressure and temperature are less than design pressure and temperature with appropriate margin Containment pressure is reduced to less than 50% of the peak accident pressure for the most limiting LOCA within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Containment pressure responses after 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> for LOCAs that do not produce the peak accident pressure are maintained below 50% of the peak pressure for the most limiting LOCA Containment atmosphere remains sufficiently mixed such that deflagration or detonation does not occur inside containment 7
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BWRX-300 Containment Evaluation Method Demonstration Analyses
- Containment analysis method for BWRX-300 thermal-hydraulic performance is used to demonstrate that the containment design satisfies the acceptance criteria for:
Large-Break Loss-of-Coolant Accident (LBLOCA)
Small-Break Loss-of-Coolant Accident (SBLOCA)
- Analyzed containment DBEs include liquid and steam breaks
- TRACG code is to calculate the mass and energy release and GOTHIC code to calculate the containment response
- Acceptance criteria were satisfied for the LTR demonstration cases 8
TRACG Code - Overview for BWRX-300
- Overview of TRACG code Latest TRACG versions used in analysis, no significant changes since ESBWR RPV model and internal components scaled from ESBWR De-coupled method assumes Containment remains at atmospheric pressure
- Past TRACG approval and relevance to BWRX-300 ESBWR qualification extended to BWRX-300, such that ESBWR PIRT and model biases applied for RPV and internals BWR/2-6 methods evoked since some events result in core uncover ICs safety function changed and modeled in considerably more detail Modeling deemed adequate for M&E release calculations (w/ L&Cs applied) 9 We make SAFE use of nuclear technology POSSIBLE.
TRACG Code - Mass and Energy Release Calculation Methodology
No suppression pool ICs are the primary decay heat removal path
- RPV isolation valves limits break flow and M&E release for large piping but small breaks are un-isolated and continue blowdown for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />
- One ICS train inoperative (due to limiting single failure)
- Conservative inputs for initial power level, power history, scram time, choke flow model, atmospheric pressure break boundary condition and bounding operating conditions 10 We make SAFE use of nuclear technology POSSIBLE.
TRACG Code - Mass and Energy Release Calculation Methodology Significant Issues and Resolution RAI - Radiolytic gas accumulation and removal in the ICs L&C 1: total volumetric fraction of radiolytic gases in the IC lower drum limited to a sufficiently low level such that condensation heat transfer in the ICs is not adversely affected and the hydrogen deflagration margin is maintained RAI - ICs return line steam trap L&C 2: IC return line layout must include a loop seal, or water trap, that prevents reverse flow from RPV back into the IC return line 11 We make SAFE use of nuclear technology POSSIBLE.
GOTHIC Code Overview for BWRX-300
- Overview of GOTHIC code An established industry code widely used in the containment response analysis 10 CFR Part 50, Appendix B compliant code Latest GOTHIC version 8.3 used in the BWRX-300 analysis
- Past GOTHIC approval and relevance to BWRX-300 GOTHIC previously approved for containment response analysis BWRX-300 containment PIRT consistent with GOTHIC functionalities BWRX-300 relevant GOTHIC benchmarking against CVTR test data reviewed GOTHIC is qualified for the thermal and species stratification and 3D effects 12 We make SAFE use of nuclear technology POSSIBLE.
GOTHIC Code - Containment Response Calculation Methodology
- Based on Reg Guide 1.203, "Transient and Accident Analysis Methods
- Decoupled M&E release from the TRACG RPV model with no backpressure as a containment BC for the stand-alone GOTHIC containment model
- 4-component GOTHIC model
- Containment (nodalized)
- Dome (nodalized)
- PCCS (nodalized)
- Reactor Cavity Pool (lumped)
- Conservative Diffusion Layer Model (DLM) used for condensation
- Thermal stratification inside the containment 13 We make SAFE use of nuclear technology POSSIBLE.
Staff Review of the BWRX-300 GOTHIC Containment Response Methodology
- Physical phenomena (GOTHIC PIRT)
- GOTHIC input model (Nominal inputs, assumptions, and correlations)
- Key modeling uncertainties and conservative biases -- Overall GOTHIC model conservatism
- Nodalization sensitivity studies for the containment and PCCS
- Benchmark predictions of test data
- BWRX-300 containment response analyses for large/small breaks
- PCCS capacity to mitigate the containment pressure in the long-term.
- Containment mixing for combustible gases
- Staff confirmatory analyses 14 We make SAFE use of nuclear technology POSSIBLE.
Significant Containment-specific Issues & Resolutions
- Break location & and break flow orientation sensitivities Limiting PCP LBLOCA location and orientation modified A liquid, and not steam, SBLOCA is limiting
- Sensitivity to containment nodalization Potential for reverse flow for SBLOCA and non-condensable gas return to RPV L&C #3 - No break flow reversal
- Containment heat transfer modeling Identification of the PCCS condensation modeling error.
- PCCS modeling and nodalization sensitivity study L&C #4 - Applicability to the final PCCS design for licensing basis 15 We make SAFE use of nuclear technology POSSIBLE.
RPV-specific Limitations and Conditions
- L&C #1 The use of this CEM is limited to a BWRX-300 design that limits the total volumetric fraction of radiolytic gases in the IC lower drum to a sufficiently low level throughout a 72-hour period following the event such that condensation heat transfer in the ICs is not adversely affected and the hydrogen deflagration margin is maintained
- L&C #2 The use of this CEM is limited to a BWRX-300 design that a proper isolation condenser return line layout is chosen, such as a loop seal or a water trap, to prevents reverse flow from RPV into the IC return line throughout a 72-hour period following the event or where an applicant or licensee referencing this report demonstrates that the TRACG code is capable of conservatively modeling the overall ICs heat removal capacity when reverse flow occurs in the IC discharge lines.
16 We make SAFE use of nuclear technology POSSIBLE.
Containment-specific Limitations and Conditions
- L&C #3.
The use of this CEM is limited to a BWRX-300 design in which the PCCS is sized sufficiently large such that a reverse flow from containment back to RPV does not occur during the first 72-hours into the event. The applicant or licensee referencing this report needs to demonstrate that no reverse flow could occur, or any reverse flow that occurs under the most bounding flow reversal conditions resulting in the degradation of IC heat transfer is not safety-significant with respect to the acceptance criteria for the BWRX-300 CEM.
- L&C #4.
The use of this CEM was demonstrated for a BWRX-300 design with the PCCS described in this LTR. For any alternate PCCS design configuration and placement, the applicability of this method and the PCCS modeling approach must be reviewed and found to be acceptable by the NRC for BWRX-300 licensing-basis analyses.
17 We make SAFE use of nuclear technology POSSIBLE.
Conclusions
- The proposed BWRX-300 analytical approach, and TRACG/GOTHIC modeling described in the LTR for M&E release and containment response are acceptable, with the appropriate conservative biases and modeling inputs to address the model uncertainties.
- With the four Limitations and Conditions specified in the staff SER Section 7.0, the NRC staff concludes that the evaluation methodology presented in GEH LTR NEDC-33922P, Revision 2, is acceptable for BWRX 300 containment peak containment pressure and temperature analysis of the containment design basis accidents.
- The NRC staff will evaluate the regulatory compliance of the final BWRX-300 containment design using the CEM during the future licensing activities, in accordance with 10 CFR Part 50 or 10 CFR Part 52, as applicable.
18 Proprietary Information We make SAFE use of nuclear technology POSSIBLE.
Meeting Summary Meeting Title ACRS Subcommittee Meeting - Containment Evaluation Meeting Start Time 3/18/2022, 11:56:56 AM Meeting End Time 3/18/2022, 3:44:56 PM Meeting Id cdbd34f7-2b0d-47aa-8257-8272a09baa49 Full Name Email Snodderly, Michael Michael.Snodderly@nrc.gov March-Leuba, Jose Jose.March-Leuba@nrc.gov Campbell, Shawn Shawn.Campbell@nrc.gov Brown, Christopher Christopher.Brown@nrc.gov Schichlein, Lisa (GE Power Portfolio) lisa.schichlein@ge.com Dashiell, Thomas Thomas.Dashiell@nrc.gov Burkhart, Larry Lawrence.Burkhart@nrc.gov Court Reporter - Sam Wojack (Guest)
Nolan, Ryan Ryan.Nolan@nrc.gov Heck, Charles (GE Power Portfolio) Charles.Heck@ge.com Shea, James James.Shea@nrc.gov Carl Thurston Syed Haider Joe Staudenmeier Ireland, Andrew Andrew.Ireland@nrc.gov Vesna B. Dimitrijevic Schiller, Alina Alina.Schiller@nrc.gov Kurul, Necdet (GE Power Portfolio) necdet.kurul@ge.com White, Frostie (GE Power Portfolio, consultant) Frostie.White@ge.com Gilligan, Bernard Bernard.Gilligan@hal.hitachi.com George, Thomas L. GeorgeT@zachrynuclear.com Li, Guangjun (GE Power Portfolio) Guangjun.Li@ge.com Matsumoto, Jun Jun.Matsumoto@hal.hitachi.com Lien, Peter Peter.Lien@nrc.gov Hinds, David H (GE Power Portfolio) david.hinds@ge.com Delja, Aleksandar Aleksandar.Delja@cnsc-ccsn.gc.
Li, Chang Chang.Li@nrc.gov Ballinger, Ronald Ronald.Ballinger@nrc.gov Dudek, Michael Michael.Dudek@nrc.gov Krepel, Scott Scott.Krepel@nrc.gov Harrington, Roseanne (GE Power Portfolio) Roseanne.Harrington@ge.com Daigle, David Louis dldaigle@tva.gov Ball, Erick Erick.Ball@nrc.gov Wadkins, George (GE Power Portfolio) George.Wadkins@ge.com Pappone, Daniel C. (GE Power Portfolio) daniel.pappone@ge.com Bellinger, Alesha Alesha.Bellinger@nrc.gov Fice, Kevin kevin.fice@cnsc-ccsn.gc.ca Lu, Shanlai Shanlai.Lu@nrc.gov Parillo, John John.Parillo@nrc.gov Skov, Tammy Tamara.Skov@nrc.gov Stubbs, Angelo Angelo.Stubbs@nrc.gov Nie, Jinsuo Jinsuo.Nie@nrc.gov
Sircar, Madhumita Madhumita.Sircar@nrc.gov Esmaili, Hossein Hossein.Esmaili@nrc.gov Diaz-Quiroz, Jesus G. (GE Power Portfolio) Jesus.Diaz-Quiroz@ge.com Proffitt, Andrew Andrew.Proffitt@nrc.gov Adam Stein (Breakthrough Institute) (Guest)
Walker, Shakur Shakur.Walker@nrc.gov Tabatabai, Omid Omid.Tabatabai-Yazdi@nrc.gov Lanese, Louis (GE Power Portfolio, consultant) Louis.Lanese@ge.com Barrett, Antonio Antonio.Barrett@nrc.gov Murray, Charles Charles.Murray@nrc.gov Armstrong, Kenneth Kenneth.Armstrong@nrc.gov Walker, Sandra Sandra.Walker@nrc.gov