ML12088A458
| ML12088A458 | |
| Person / Time | |
|---|---|
| Site: | Indian Point  |
| Issue date: | 01/26/2005 |
| From: | Advisory Committee on Reactor Safeguards |
| To: | Atomic Safety and Licensing Board Panel |
| SECY RAS | |
| References | |
| RAS 22104, 50-247-LR, 50-286-LR, ASLBP 07-858-03-LR-BD01 | |
| Download: ML12088A458 (27) | |
Text
ENT000087 Submitted: March 28, 2012 Official Transcript of ProceedingsAn NUCLEAR REGULATORY COMMISSION
Title:
Advisory Committee on Reactor Safeguards Thermal Hydraulic Phenomena Subcommittee
-J Docket Number: (not applicable)
PROCESS USING ADAMS I,-
- F4 '
TEMPLATE: ACRS/ACNW-005 IC)3 Location: Rockville, Maryland SISP REVIEW COMPLETE Date: Wednesday, January 26, 2005 Work Order No.: NRC-1 94 Pages 1-364 NEAL R. GROSS AND CO., INC.
Court Reporters and Transcribers 1323 Rhode Island Avenue, N.W.
Washington, D.C. 20005 (202) 234-4433 G TUMOF.TPE COMMITTEE
. 4.
DISCLAIMER UNITED STATES NUCLEAR REGULATORY COMMISSION'S ADVISORY COMMITTEE ON REACTOR SAFEGUARDS January 26, 2005 The contents of this transcript of the proceeding of the United States Nuclear Regulatory Commission Advisory Committee on Reactor Safeguards, taken on January 26, 2005, as reported herein, is a record of the discussions recorded at the meeting held on the above date.
This transcript has not been reviewed, corrected and edited and it may contain inaccuracies.
1 1 UNITED STATES OF AMERICA 2 NUCLEAR REGULATORY COMMISSION 3
4 MEETING 5 ADVISORY COMMITTEE ON REACTOR SAFEGUARDS 6 (ACRS) 7 SUBCOMMITTEE ON THERMAL-HYDRAULIC PHENOMENA 8
9 WEDNESDAY, 10 JANUARY 26, 2005 11 12 ROCKVILLE, MARYLAND 13 14 15 The Subcommittee met at the Nuclear Regulatory 16 Commission, Two White Flint North, Room T2B3, 11545 17 Rockville Pike, at 8:30 a.m., Dr. Graham Wallis,
- 18. Chairman, presiding.
19 COMMITTEE MEMBERS:
20 GRAHAM B. WALLIS, Chairman 21 F. PETER FORD, Member 22 THOMAS S. KRESS, Member 23 VICTOR H. RANSOM, Member 24-; STEPHEN L. ROSEN, Member 25 JOHN D. SIEBER, Member NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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2 1; ACRS STAFF PRESENT:
2e RALPH CARUSO 33- NRC STAFF PRESENT:
HERBERT BERKOW V.
ROBERT DAVIS 6 MICHELLE HART 7- STEVE JONES 8 N. (KALY) KALYANAM 95 RICHARD LOBEL 1 O- LOUISE LUND 1 fKAMAL MANOLY 12 - L.B. (TAD) MARSH 13, JAMES MEDOFF 14 J SAM MIRANDA 15, KRIS PARCZIEWSKI 16- PAUL PRESCOTT 17 WILLIAM H. RULAND 18' ANGELO STUBBS 19 MARTIN A. STUTZKE 2 JAMES TATUM 2I JOHN TSAO 2i2 .LEN W. WARD 23`
24' 25.
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3 17 ALSO PRESENT:
2 tROB ALEKSICK, CSI Technologies 3 JEFF BROWN, Westinghouse 4s PRASANTA R. CHOWDHURY, Entergy 5$ JOSEPH CLEARY, Westinghouse
- 6. DAVID CONSTANCE, Entergy 7- STEVEN CYBERT, Westinghouse 8- THOMAS FLEISCHER, Entergy 9' JAMIE GOBELL, Entergy 10 MARIA ROSA GUTIERREZ, Entergy 11$ ALAN HARRIS, Entergy 12; JERRY HOLMAN, Entergy
- 13. THEODORE LEONARD, Entergy G. SINGH MATHARU, Entergy 15- JOSEPH REESE, Entergy
- 16. RALPH K. SCHWARTZBECK, Enercon 17 PAUL SICARD, Entergy 18 DON SISKA, Westinghouse 19,. DAVID VIENER, Entergy 20'- ARTHUR (GENE) WEMETT, Entergy 2W 22 23" 24-w ~25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS
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4 A-G-E-N-D-A 2 INTRODUCTION . . . . . . . . . . . . . . . . . . 6 3 OPENING REMARKS, Tad Marsh . . . . . . . . . . . 8 4 INTRODUCTION, N. Kalyanam . . . . . . . . . . . . 13 5, LICENSEE PRESENTATION 6-^ Overview of EPU, Tim Mitchell . . . . . . . 21 7- Safety Analysis, Paul Sicard . . . . . . . 27 8 Risk Considerations, Jerry Holman . . . . . 88 9 Engineering Plant Impact, David Viener . 110 10 Operational Impact, Gene Wemett . . . . . 144 1 RCS Flow, Paul Sicard . . . . . . . . . . 178 12 Concluding Remarks, Tim Mitchell . . . . 181 13, STAFF'S PRESENTATION 41 Mechanical and Chemical Engineering, Jim Medoff 182 15Bob Davis . . . . . . . . . . . . . . . . 190 16l John Tsao.. . ..... 195 17 Mechanical and Civil Engineering, Kamal Manoly 207 18.: Plant Systems, Angelo Stubbs . . . . . . . . . 215 19 Increased flow through steam generator, Ken Karwoski, 20` EMCB . . . . . . . . . . . . . . . . . . 234 21 CHECWORKS/FAC program, Louise Lund . . . . . 238 22" Rob Aleksick, CSI Technologies . . . . . 242 23'.; Containment Performance, Richard Lobel . . . . 249 24- Reactor Systems, Sam Miranda . . . . . . . . . 259 U2 5',,~
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A-G-E-N-D-A (con't) 2; STAFF'S PRESENTATION Independent Calculations/Long Term Cooling, Len Ward . . . . . . . . . . . . . . . . 266 9; l Source Term and Radiological Consequences, Michelle Hart . . . . . . . . . . . . . . 308 Power Ascension and Testing, Paul Prescott . . 318 Risk Evaluation, Martin Stutzke . . . . . . . . 340 4 Closing Remarks, Allen Howe . . . . . . . . . . 351 115 7
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.' I 196 1 Okay. I also review the section on leak 2 before break. And the operating conditions under the 3 uprated conditions will not alter the conclusions of 4 the previous leak before break analysis for Waterford 5 3. It's still valid.
6 Are there any additional questions?
7 I'll turn it over to John Tsao.
8 MR. TSAO: I'm John Tsao from the 9 Materials and Chemical Engineer Branch. I reviewed 10 five sections; coding system, flow accelerated 11 corrosion programs, steam generator tube inspections, 12 steam generator blowdown systems and chemical and 13 volume control systems.
14 I will be talking about only two systems 15 here; flow accelerated programs and steam generator 16 tube inspections because they are more significant in 17 terms of power uprate.
18 For the flow accelerated corrosion 19 programs, this morning there was some issue as to how 20 much you increase. I have this backup slide.
21 The FAC program measure the wear rates in 22 terms of mils per year. And these are the changes 23 that would be due to power uprate conditions.
24 Also, I want to show you another slide 25 1 that gives the effectiveness of the FAC program. This NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE.. N.W.
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197 1 is provided by the licensee. And as licensee said, it 2 is more in the -- they used CHECWORKS. It's a 3 computer program that considers hydrodynamics, heat 4 balance, temperature in particular.
5 As you can see the predictive method is 6 conservative considered to actual measurement.
7 DR. FORD: I'm sorry. Could you explain 8 that?
9 MR. TSAO: Okay.
10 DR. FORD: It looks as though it's equally 11 scattered around the one to one line. So why are you 12 saying it's conservative?
13 MR. TSAO: Well, for example, you can see 14 -- let's see.
15 You can see just for example, this point 16 here the measurement is about 300 mils. The predict
- 17. value, let's say, from here to here is about 240 mils.
18' So what it says is that the methodology will predict 19 that the tube wall thinner than measured, therefore it 20 also indicated that the licensee may need to do some 21 monitoring or replacement of that pipe.
22 DR. FORD: But equally there are points on 23 the other side which are not, what you call it --
24 MR. TSAO: Well, that's true. Yes, that's 25 correct. But as you know this is only a prediction.
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198 1 Predictions, hopefully -- well, from the data point 2 you can see they are scattered toward the conservative 3 side. And also the FAC program according to EPRI is 4 that it's a process. In other words, the licensees 5 would go out, make an inspection, UT or ultrasonic 6 measurements or the pipe thickness and then they will 7 come back and they input that data into the computer 8 code so that to make sure there is a certain accuracy 9 in their predictions.
10 Also predict that the -- in the prediction 11 method they include some safety factors.
12 DR. FORD: It seems to me as though 13 there's a huge amount of scatter around that one-to-14 one line. And so the question immediately arises as 15 to what is the impact of that in terms of could you 16 get a through wall erosion event taking place when you 17 had predicted it would not have done so?
18 MR. TSAO: It could.
19 DR. FORD: Did you go through that sort of 20 "what if" argument? I mean if you look at that data 21 base, you don't really have too much confidence in 22 CHECWORKS.
23 MR. TSAO: Well, I wouldn't say they would 24 be relying on CHECWORKS per se. The licensees, not 25 only Waterford but other licensees, you know they NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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199 1 include other factors. For example, other industry 2 experience. You know if some plants have some problem 3 with FAC water lines, then they will consider --
4 DR. FORD: I recognize that.
5 MR. TSAO: Right.
6 DR. FORD: But this particular EPU is 7 putting a lot of basis on CHECWORKS to manage this 8 problem. And if this a general observation as to how 9 good CHECWORKS is, my confidence is a little bit 10 shattered.
11 MR. TSAO: I should point out that 12 Waterford is not unique. I did the review for license 13 renewal, and I also asked questions. And this is type 14 of plot that, you know, other licensee has shown me.
15 DR. FORD: Yes, I know.
16 MR. TSAO: In other words, I don't think 17 that licensee is depending solely on what prediction 18 is. They also, you know, include other experiences and 19 inspections. Not only the inspections for the fact, 20 but there are other SME code inspections they have to 21 perform.
22 DR. FORD: I'll ask again. Did you go 23 through the "what if" scenario?
24 MR. TSAO: I have Kris Parcziewski from my 25 branch to elaborate on this.
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200 1 DR. FORD: With that amount of uncertainty 2 in your modeling capability and therefore your 3 management capability, do you not feel uncomfortable?
4 MR. TSAO: No.
5 DR. FORD: No?
6 MR. PARCZIEWSKI: Kris Parcziewski from 7 the Chemical Engineering Branch.
8 To answer your question, those points are 9 predicted. CHECWORKS predicts but in addition there 10 is a correction factor for each individual line which 11 is here at the top right hand side, line correction 12 factor which indicates that it is corrected for each 13 individual line all the points predicted in the line 14 are corrected by this line correction factor. And the 15 line is defined as a portion of the system which has 16 the same chemistry but not necessarily the same 17 temperature. If I answer your question.
18 So all those points are already corrected.
19 Ideally, if they were ideal, they would lie in the 45 20 degree line, the middle line. However, obviously, 21 there is some scatter.
22 DR. FORD: I understand the physics --
23 MR. PARCZIEWSKI: Yes.
24 DR. FORD: -- of the erosion process.
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201 1 temperature. Highly dependent on corrosion potential 2 and all of those things are interacting. So that if 3 you're a little bit off on your definition of one of 4 those parameters, then you're going to get a big 5 change. So I can understand why there is a scatter 6 there because you're not able to define your system 7 adequately enough, and therefore that's the physical 8 origin of your LCF. But I still feel uncomfortable 9 about that huge scatter and how you use it in 10 management from their point of view and in terms of 11 regulation from your point of view.
12 MR. TSAO: Okay. For regulation, 13 basically there's no regulation on FAC program.
14- DR. FORD: That's what worries me.
15 MR. TSAO: The FAC program is instituted 16 because of the bulletin. Back in the '80s it was 17 result of Bulletin 87-01 where Surry had a --
18 DR. FORD: Yes, sure.
19 MR. TSAO: -- a rupture. And Generic 20 Letter 89-08 that required the licensees to institute 21 some type of program, FAC program. And then the 22 industry, you know, with EPRI guidance come up with 23 this program. And so --
24 DR. FORD: I understand all that. I'm 25 just looking at what the history has been since then.
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202 1 And, you know, a few months ago we had fatalities in 2 Japan because of this phenomnen6n, which was not 3 managed well. And you know if this is supposed to be 4 the state-of-the-art of prediction of management and 5 therefore regulation, I just don't feel comfortable.
6 MR. TSAO: Okay. Speaking of the 7 Japanese, again from my understanding is that Japanese 8 did not inspect, you know, the last 20, 30 years.
9 DR. FORD: Correct.
10 MR. TSAO: Where here under FAC program 11 the licensees will have to inspect at least they say 12 50 to 100 inspection points for their large bore 13 piping and small bore piping they probably sometime
> 14 inspect 100 percent. And so there's a constant 15 inspections going on to make sure that the --
16 DR. FORD: I understand that.
17 MR. TSAO: Right.
18 DR. FORD: All I'm pointing out is 19 everyone bows to CHECWORKS and says yes, yes that's 20 the best thing that's around. And I'm just 21 questioning it. Is it adequate?
22 MR. HOWE: This is Allen Howe.
23 And I'd just like to add in at this point 24 that we understand the question and we will be happy 25 to get back with you with a response on that.
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203 1 DR. FORD: Thank you.
2 MR. TSAO: Okay. Next slide.
3 Next slide I will be talking about is the 4 related to steam generator tube inspections.
5 This morning you also raised about the 6 question that -- sorry.
7 Next slide. The power operator will effect 8 the anti-vibration tubes for locations. What it does 9 at the increase of feedwater flow will cause the tube 10 to vibrate a little bit more. And the possible 11 degradation is where the anti-vibration bar, they call 12 the bat wings on top of that square shape, hitting the 13 supports.
14 Now, we have the requirement in tech spec 15 that we have the leakage requirement, which the 16 licensee has reduced to 75 gallons per day of a steam 17 generator. This is pretty significant in that the 18 normal primary to secondary leakage limit is 150 19 gallons per day. And Waterford is willing to go down 20 to 75 gallons per day. And that it is very good 21 limits to detect any potential leakage. Because 75 for 22 tech spec translate into administrative limit.
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240 1 by the ASME 3 code or anything like that. Similarly 2 it's just stress code in cracking that's been 3 accelerated.
4 MR. SIEBER: But wear phenomenon is 5 covered by the ASME code.
6 DR. FORD: Yes.
7 MR. KARWOSKI: Through the plugging limits 8 and what not and through the plant technical 9 specifications.
10 DR. FORD: Right.
11 CHECWORKS?
12 MR. KARWOSKI: I think Louise Lund was 13 going to talk about CHECWORKS.
14 DR. FORD: Maybe if I could just state 15 what my problem was, Louise, and that would make it 16 more efficient for you to answer it.
17 MS. LUND: Should I introduce myself first 18 for the record?
19 DR. FORD: Yes.
20 MS. LUND: I'm Louise Lund. I'm the 21 Section Chief for the Steam Generator and Integrity 22 and Chemical Engineering Section, NRR. And, anyway, 23 I was asked to come over and discuss the FAC program.
24 DR. FORD: My concern was that the way 25 that they're using CHECWORKS right now, it is NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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241 1 primarily a prioritization tool as to where you're 2 going to look in the carbon steel piping. From the 3 measures that were shown this morning, it's apparent 4 that CHECWORKS is not good on one-to-one correlation.
5 Therefore, it's quite possible that you may use 6 CHECWORKS to say that I should not look at that pipe 7 because of the particular operating conditions of that 8 pipe, but I should look at this pipe. But in fact that 9 pipe there might well be eroding at quite a large 10 rate, but you wouldn't look at it for one, two, three 11 cycles. In that time you could go through wall. So 12 that was essentially my worry that you're using a 13 model which is not precise to make prioritization 14 decisions.
15 MS. LUND: Right. And I just want to say 16 off the top, you know we have a very active interest 17 in the FAC programs. Specifically we've had generic 18 letters or generic correspondence that has asked 19 industry to put together these type of programs which 20 manage FACs and also have these predictive 21 methodologies. However, it's not a case of just using 22 the predictive methodologies blindly and looking at 23 information on one line or another; there's a number 24 of things that inform the decision as far as what's 25 inspected and how it's inspected. Because it is a NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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242 1 tool, but it's not a blind tool in that particular 2 way. And, in fact, this gentleman I believe is from 3 Waterford and he was mentioning, we had a kind of 4 off line discussion about it and that's why I asked him 5 to come up here and help discuss this, and 6 specifically for Waterford.
7 I also wanted to say that for these FAC 8 programs, I think that we have an interest in looking 9 at them through power uprate and license renewal in 10 that we ask that the licensee provide information on 11 their most susceptible lines with their measures 12 versus their predicted and whether it gave them 13 information such that they could replace the lines, 14 you know, in a timely manner. Because that's really 15 what we want to know is, is it giving you the 16 information at the time that you need it in order to 17 make the decisions you need to make good decisions 18 about running your plant.
19 So that's the kind of questions we ask. We 20 do not do a re-review of their CHECWORKS data. We do 21 not take all their raw data and subsequently do an 22 audit of it. Okay. So I just wanted to kind of 23 clarify what it is that we do, you know, in our review 24 process. Usually through a request for additional 25 information we usually will ask them for the most NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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243 1 susceptible lines.
2flMR. ROSEN: We call that a performance-V based regime?
4 MS. LUND: Right. Right. And when we put 5 out that generic letter where we asked the licensees 6 to put together a FAG program and also have these 7 predictive methodologies, we did inspections of those 8 programs at that time. Okay. In fact, to make sure 9 that these programs were in place and in fact doing 10 what we thought that they were doing. Okay.
11 Now, I now in license renewal, true 12] license renewal we've been asked to come and give a 13~ presentation to the ACRS on FAG and FAG programs. And 14 we've actually been in contact with CHECWORKS user 15.: script to ask them to come in and help present this 16' information such that you can look industry-wide at 17, how well these FAC programs are working, specifically 18 with the CHECWORKS program and give you a lot of sense 19 -- instead of looking at just one graph, kind of get 20 a sense for generically how this is working and where 21 it may be challenged in certain ways or another, 22 because they think that they have a very good story to 23~ tell.
24' Now maybe if you could introduce yourself, 251 and then also explain how programmatically it'Is a much NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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244 1 lighter look at how you choose the lines and --
2 because there's a surrogate aspect to it where, you 3 know, if you see something you look at other things 4 that are like that. There are a lot of things that go 5 into the program that don't rely on just this 6 measurement.
7 So, anyway --
8 MR. ALEKSICK: Good afternoon. My name is 9 Rob Aleksick. I'm with CSI Technologies representing 10 Entergy today.
11 Real quick about my background. I've had 12 the opportunity to be involved with flow accelerated 13, corrosion since 1989 and in particular have modeled or 14 otherwise addressed approximately 20 EPU efforts in 15 the last two years.
16 Dr. Ford made a very good point earlier 17 when he said that the graph that we looked at did not 18 display a very good correlation between the measured 19: results and the predicted results out of CHECWORKS.
20 Programmatically -- well, let me back up a second.
21, That is certainly true in the example that we looked 22 at. That is not always the case.
23 CHECWORKS models are on a per line or per 24 run basis. The run --
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245 1, graph that we saw? The graph was a plot of thickness 2r versus predicted thickness.
3: MR. ALEKSICK: That's correct.
4 CHAIRMAN WALLIS: Because if you looked at 5 amount removed versus predicted amount removed, it
- 6. seems to me the comparison will be even worse.
7 MR. ALEKSICK: That's correct. In fact --
8 CHAIRMAN WALLIS: That's what you're 9 really trying to predict is how much is removed.
101 MR. ALEKSICK: Yes, that is true. And my 11 point is that in some subsets of the model, the one 12' that we looked at here which was high pressure 13: extraction steam, the correlation between measured and 14.' predicted is not so good. And in some subsets of the 15: model, the correlation is much better.
16, CHAIRMAN WALLIS: It looks to me that in 171 some cases it's predicting no removal whereas in fact 18 there's a lot of removal. So the error is percentage 19i wise enormous?
20 MR. ALEKSICK: Yes, exactly. Exactly.
21 Some runs results are imprecise and some more precise.
22t And we look at both accuracy and precision.
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246
, coming out of the model that are substantiated by 2 observations, we treat those piping segments 3; differently programmatically than we do areas where 4 the model is less good. If the model results do not 5t correlate well with reality, different actions are 6' taken primarily increased inspection coverage to 7 increase our level of confidence that those systems 8' can continue to operate safely.
9 In addition to the CHECWORKS results many 10, other factors are considered to assure that the piping 11 retains its integrity, chief among these are industry 12 experience as exchanged through the EPRI sponsored 13k CHUG group. Plant experience local to Waterford in K14 this case. And the FAC program owner maintains an 15.~ awareness of the operational status of the plant so 16; that, for example, modifications or operational 17! changes that occur are taken into account in the 18i inspection of the secondary site FAC susceptible 19: piping.
20; DR. FORD: And my final question on this 21j particular subject was given the uncertainties in the 221 model, changed by this performance based aspect that 23t you just talked about, is there any way that you can 24k come up with a quantification of the risk associated K 25 with a failure of a specific pipe?
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247 1t MR. ALEKSICK: There's currently no 2:: accepted methodology to quantify that risk, no.
However, it is accounted for primarily on a judgment 4 basis through industry experience and information 5~ exchange through the EPRI CHUG group.
6; DR. FORD: Okay.
- 7. MR. MITCHELL: Yes, this is Tim Mitchell.
8 Just to give you a feel for how we're 9 addressing for this upcoming refueling outage, we have 10 increased our scope for a couple of reasons. One to 11i get additional data and we always do more than just 12! exactly what CHECWORKS supports. So you're always out 13; validating and getting more data to be able to help 14' predict where do you need to be looking. But in 15 addition, we're taking some additional points to make 16^ sure we have good baseline data for the next cycle to 17 ensure that those points give us a good indication 18' going forward after the EPU.
19 The analysis for flow accelerated 20' corrosion shows very minimal changes as a result of 21 power uprate. But we are taking seriously our
- 22. inspection program and expanding it for this upcoming 23 outage to ensure that we know what's happening not 24 just what we're predicting.
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248 1 Tim. Can you tell me like for the last three or four 2 outages have you done some actual replacement of 3 piping based on predictions of FAC from the CHECWORKS 4' code or have you never replaced anything? What are 5 you seeing at Waterford?
6 MR. MITCHELL: I can give you non-7 Waterford data better than I can give Waterford to 8 ponder.
9 MR. CHOWDHURY: My name is Prasanta 10 Chowdhury and I'm working with Entergy design for last 11 20 years.
12 I was involved with FAC also for several 13 years in the past.
14 It's not the CHECWORKS model that 15 determines what replacement is to be done. We base it 16 on actual measurement we take during the refuel 17 outage. So we also project based on actual measurement 18 that what will be our future projected thickness in 19 next refueling outage. So you can survive until next 20 cycle. And then we do some evaluation based on our 21 criteria that makes the stress criteria -- or based on 22 the code requirement. Like make all the equation.
23 Now code allows to go thinning in local 24 area but the FAC is a local thinning. So we do some 25 local thinning evaluation to make sure that it goes to NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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249 1 the next cycle.
2 Does that answer your question?
3 MR. ROSEN: No.
4 MR. MITCHELL: Did we replace any piping 5 in the last three outages?
6 MR. CHOWDHURY: I don't recall. I don't 7 recall. But we did extensive modification on 8 extraction steamline in the past. But it changed to 9 crack piping or stainless steel piping or chrome moly, 10 which is more corrosion resistance piping. I don't 11 answer your question --
12 MR. ROSEN: You say you have made 13 extensive modifications --
14 MR. CHOWDHURY: In the past.
15 MR. ROSEN: -- you changed to chrome moly?
16 MR. CHOWDHURY: Several years back, yes.
17 MR. ROSEN: Okay.
18 MR. CHOWDHURY: So whatever we did, see 19 the corrosion of thinning, we took it out and made 20 modifications.
21 MR. ROSEN: Yes, well, that's typically 22 the plant's response. If you find substantial 23 thinning, then you just don't go back and put in 24 carbon steel back in the same place.
25 MR. CHOWDHURY: Right.
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11 4
250 1 MR. ROSEN: Because what happened before 2 will happen again.
3 MR. CHOWDHURY: I mean we have also made 4 a procedural entry into this FAC that anytime we do a 5 replacement, we use a better corrosion resistant 6 material or EPRI guidelines.
7 MR. ROSEN: Okay. So you're saying you 8 have made those kinds of modifications.
9 MR. CHOWDHURY: Yes. But still we are 10 ongoing and doing things. If we see something we need 11 to change, we change it.
12 Does that answer your question, sir?
13 MR. ROSEN: It's a little better. Not a 14 100 percent.
15 MR. CHOWDHURY: Okay.
16' MR. ROSEN: I would prefer something, and 17 maybe for next meeting you can come back with some 18 real data that there are 11 locations that you changed 19 in the last five years or something.
20 MR. CHOWDHURY: Yes, we can do that.
21 Because I don't have the data with me. I can get in 22 touch with the FAC program engineer and get those 23 information. Thank you.
24 CHAIRMAN WALLIS: That would be excellent.
25 DR. FORD: Thanks very much indeed. I NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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251 1 appreciate it.
2 MR. KALYANAM: Next we have the 3 Containment Systems group Richard Lobel.
4 MR. LOBEL: Good afternoon. My name is 5 Richard Lobel. I'm with the Probabilistic Safety 6 Assessment Branch but in the Containment System area.
7 Next slide, please.
8 I wanted to talk about the review of the 9 analysis that were done for the containment accident 10 analysis. This slide lists the areas that were looked 11 at. Basically the analysis of containment response to 12 a LOCA both the mass release and the containment 13 response and the containment response to a main 14 steamline break, both mass and energy into the 15 containment and the containment response and 16 subcompartment analysis also, which is a type of LOCA.
17 Next slide.
18 CHAIRMAN WALLIS: You mean that PSA Branch 19 actually does this sort of thermal-hydraulic analysis?
20 MR. LOBEL: We're the orphan section. We 21 go to the branch meetings but don't understand what 22 they're talking about, because it's all acronyms 23 dealing with risk and we just sit there and listen.
24 But that's where they put us.
25 The mass and energy for the LOCA was NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.
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