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Transcript of 980618 ACRS Subcommittee on Advanced Reactor Designs Meeting in Rockville,Md.Pp 236-310.W/reporters Certificate
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Issue date:	06/18/1998
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RGLNAL Ad8S7= 30Y3 OFFICIAL TRANSCRIPT OF PROCEEDINGS NUCLEAR REGULATORY COMMISSION ADVISORY COMMITTEE ON REACTOR SAFEGUARDS

Title:

SUBCOMMITTEE ON-ADVANCED REACTOR DESIGNS TRC4 (gcpg! Docket No.: RETURN ORIGINAL B J W}.fl T E 4 s M/S T-2E26 415-7130 THANKs! Work Order No.: ASB-300-344 I LOCATION: Rockville, Maryland DATE: Thursday, June 18,1998 PAGES: 236-310 624( 6 980618 0 T 7043 ros ANN RILEY & ASSOCIATES, LTD. 1250 i Street, NW, Suite 300 g . d j ()() } Washington, D.C. 20005 U ACTS 0"Ee'dcijy-RETT Fo"::e Life of1:ne Com": tee

l O DISCLAIMER UNITED STATES NUCLEAR REGULATORY COMMISSION'S ADVISORY COMMITTEE ON REACTOR SAFEGUARDS 1 JUNE 18, 1998 The contents of this transcript of the proceeding of the United States Nuclear Regulatory Commission Advisory Committee on Reactor Safeguards, taken on June 18, 1998, as reported herein, is a record of the discussions recorded at the meeting held on the above date. This transcript had not been reviewed, corrected and edited and it may contain inaccuracies. O

236 1 UNITED STATES NUCLEAR REGULATORY COMMISSION 2 ADVISORY COMMITTEE ON REACTOR SAFEGUARDS 3 4 5 SUBCOMMITTEE ON 6 ADVANCED REACTOR DESIGNS 7 8 9 U.S. Nuclear Regulatory Commission 10 11545 Rockville Pike 11 Room 2B-3 -12 Rockville, Maryland 20852-2738 13 14 Thursday, June 18, 1998 k 15 16 The Subcommittee met pursuant to notice at 8:30 17 a.m. 18 19 MEMBERS PRESENT: 20 JOHN J. BARTON, Chairman, ACRS 21 MARIO H. FONTANA, Member, ACRS 22 ROBERT SEALE, Member, ACRS 23 DANA A. POWERS, Member, ACRS 24 DON W. MILLER, Member, ACRS 25 GEORGE E. APOSTOLAKIS, Member, ACRS ( ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

237 1 PROCEEDINGS () 2- [8:30 a.m.] 3 CHAIRMAN BARTON: The meeting will now come to 4 order. l 5 This is the second day of a meeting of the ACRS 6 Subcommittee on Advanced Reactor Designs. 7 I'm John Barton, Chairman of the Subcommittee. 8 ACRS members in attendance are George Apostolakis, 9 Mario Fontana, Don Miller, Dana Powers, and Robert Seale. -10 We also have in attendance ACRS consultant James 11 Carroll. 12 The purpose of this meeting is to continue review 13 of the Westinghouse AP600 design. 14 Today the Subcommittee will review containment () 15 spray system design, security system design, WCAP-14477, 1 16 adverse interactions evaluation report, answers to open ACRS 17 questions, and discussion and review of the proposed ACRS 18 report on the AP600 design. 19 The Subcommittee will gather information, analyze 20 relevant issues and facts, and formulate proposed positions 21 and action as appropriate for deliberation by the full 22 committee. 23 Noel Dudley is the cognizant ACRS staff engineer 24 for this meeting. 25 Rules for participation in today's meetings have 4 ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C 20036 (202)' 842-0034 \\

238 1 been announced as part of the notice of this meeting () 2 previously published in the Federal Register on May 22, 3' 1998. 4 A transcript of the meeting is being kept and will '5 be made available as stated in the Federal Register notice. 6 It is requested that speakers first identify ( 7 themselves and speak with sufficient clarity and volume so j l i 8 that they can be readily heard. 9 We have received no written comments or requests 10 for time to make oral statements from members of the public. 11 We will now proceed with the meeting, and I call 12 upon Brian McIntyre of Westinghouse to begin. 13 -MR. McINTYRE: Okay. Thank you, Mr. Barton. 14 The first presentation today will be Terry Schulz () 15 on discussing the containment spray system design for the 16 AP600. 17 The second scheduled topic is security and then 18 followed by the adverse systems interaction. 19 If you don't mind, I'd like to reverse the adverse 20 systems interactions and the security. The security 21 reviewer won't be here until nine and hasn't seen what I'm 22 going to present, and at least he should have a few minutes 23 to look 0.t it. 24 CHAIRMAN BARTON: Sounds like a real good security 25 system to me. ANN RILEY & ASSOCIATES, LTD. s.. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

l 239 1 MR. McINTYRE: And then Mr. Schulz, if he gets () 2 done, can_then jump in his car and be back at work by noon. 3 CHAIRMAN B.%P. TON: Well, we'll have lots of 4 questions for Mr. Schulz. 5 That's fine. 6 MR. McINTYRE: Okay. We bring you Mr. Schulz 7 again. 8 MR. SCHULZ: Good morning. My name is Terry 9 Schulz, and the first topic we'd like to discuss is the 10 containment spray system for AP600. 11 This system is not a safety-related system. It's 12 not required to function during design basis accidents. The 13 doses for AP600 are limited to acceptable values with 14 natural removal mechanisms. () 15 The system is required by SECY-97-044 to provide 16 . additional capability in severe accidents. It's not 17 required to be safety-related to perform that function. 18 The design of the system uses the fire water 19 protection system to provide water from a water supply, the 20 tanks, and pressure for the spray. 21 There's a connection made to the fire protection 22 system inside containment that connects up to two ring l 23-headers that are located up in the top of the containment. 24 These nozzles are at least 100 foot above the operating deck 25 of the containment. O* ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue,'NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

r 240 1 The fire protection -- one of the fire protection () 2 pumps, either one, provides a little more than 1,000 gpm at 3 20 pai. 4 We use 20 psi because of the severe accident 5 studies that we looked at. The pressure in the containment 6 is no more than 20 psi at about an hour or so after the 7 accident, when we would anticipate the operators possibly 8 using this system. 9 The spray nozzles provide essentially 100-percent 10 coverage above the operating deck. The 83 percent comes 11 about because there's obviously regions below the operating 12 deck that aren't sprayed. l 13 The system was set up to run for about three 14 hours. 15 The system cannot run indefinitely, because it's 16 just pumping water into the containment, and we have 17 established a maximum water level that we want to allow 18 during this system operation, and at this flow rate, we've 19 got about three hours of operation. 20 DR. CARROLL: I've made this comment before, but 21 I'll make it again. Do the fire insurance underwriters like 22 your idea of compromising their fire protection system? 23 Having fought a battle of that sort once, I'm sensitive to 24 the issue. 25 MR. SCHULZ: We have not talked to insurance eg ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

i 241 1 people about this. There are in existing plants some uses () 2 of the fire system for limited back-up kind of make-ups to 3 either aux feed water or, in some cases, service water -- or 4 not service water -- CCW make-up, that kind of thing. 5 As long as there is very careful control of the 6 use of that, both from a -- say, operator procedures and a 7 mechanical type -- you know, what it takes to turn this on 8 -- and one of the things you see here, that in order to get 9 spray, we need to open this air-operated valve inside 10 containment, we need to open this lock-closed valve outside, 11 which is a containment isolation valve, and to actually get-12 water from the fire pumps, we need to open a third valve. 13 So, it's very unlikely or incredible to us that 14 this would get inadvertently used, and we think that the () 15 situation where you've actually damaged the core -- this is 16 a severe accident management kind of a thing, far beyond any 17 design basis situation. 18 So, we think that's a reasonable approach, but we 19 haven't actually discussed that. We haven't had an issue, 20 as far as I know, with the NRC staff. 21 MR. SNODDERLY: This is Mike Snodderly, 22 Containment Systems and Severe Accident Branch. 23 Dr. Carroll, if you notice, in the original 24 design, either the primary or the second fire protection 25 tanks could be use to supply the system. O-ANN RILEY & ASSOCIATES, LTD. Court Reporters 1 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

242 1 As a result of discussions with our fire () 2 protection people, they didn't like that, and the system's i 3 been changed so that now only the secondary tank, the 1 4 350,000-gallon tank, is the only tank that can supply the 5 spray system. 6 So -- 7 DR. SEALE: So, you've scratched off the 425. 8-MR. SNODDERLY: Right. And that is to be totally 9 dedicated for just fire protection purposes, and that was as 10 a result of comments from our fire protection people. 11 DR. CARROLL: Okay. 12 DR. SEALE: And there is no make-up from the sump 13 internal to the containment for this. 14 MR. SCHULZ: That is correct. It's strictly in a ) 15 external spray into the containment. There is no-recirc 16 capability. 17 DR. SEALE: Either for the sprays or for the fire 18 headers. 19 MR. SCHULZ: That's correct, yes. 20 So, you see here the basic arrangement, and as I 21 mentioned, the connection, what was added to the design was 22 this connection from the fire header inside containment up 23 to the spray nozzles, including this air-operated valve. 24 This valve is a fail-open valve, so that if you 25 actually had severe conditions in containment, it would O ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

243 1 . expect it to be already open. Air would have been shut off () 2 to the valve, that kind of thing, and even if it wasn't 3 open, it could be opened. 4 Originally,.I think we had a fail closed valve, 5 and that probably would not be expected to function in a '6 . adverse condition inside containment. So, we changed it.. 7 During a shut-down mode of operation, I'll point 8 out that this additional manual valve here is closed so that 9 the -- you can open up the fire header inside containment 10 for potential fire-fighting duties without risking 11 inadvertent spray in the containment. 12 So, again, the basic idea is that you've got 13 300,000 gallons of water or so that you can put into the 14 containment. ( 15 The system can run for about three hours in that 16 situation, and the containment water level will stay within 17 acceptable levels, within a foot or so of the levels that 18 you might reach otherwise in the containment. 19 DR. SEALE: Let me make sure I understand. 20 MR. SCHULZ: Sure. 21 DR. SEALE: The smaller of the two reservoirs over 22 there on the right is now the only one available for the 23 sprays. The other one is still there, but it's strictly 24 dedicated to fire protection. 2S .MR. SCHULZ: Right. Right. O ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

l 244 1 DR. SEALE: Okay. () 2 DR. CARROLL: And that's done by administrative 3 controls, or is it physically impossible to use it? 4 MR. SNODDERLY: I believe it's administrative 5 control, because the system's design -- I probably mis-spoke 6 when I said the system design change -- how the system will 7 be used. 8 DR. CARROLL: Okay. 9 MR. SCHULZ: Yes. There's valves in this ring 10 header that I don't show here, that separate it out, and 11 those valves will be used, along with the procedures, to 12 provide that control. 13 When would the system be used? 14 Again, its purpose is a severe accident kind of () 15 capability. 16 So, we would use the core exit thermo-couple high 17 temperature, which is an indication of loss of core cooling, 18 and get into the emergency procedures and the severe 19 accident management guidelines before this system would be 20 used by the operators. 21 I mentioned it would be run continuously until it 22 pumped in its 300,000 gallons of water or so. The 23 containment water level is limited. Post-accident 24 monitoring, qualified containment water level instruments 25 verify that the level is not too high. O ANN RILEY & ASSOCIATES, LTD. \\ssl Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

245 1 It does help with the removal of iodine. You get () 2 about a 50-percent reduction in iodine ~by running the system 3 in this way. 4 DR. FONTANA: Is that figured on elemental or 5 aerosols or both? I 6 MR. SCHULZ: Aerosols. 7 DR.-FONTANA: Okay. 8 MR. SCHULZ: Exactly 9 DR. FONTANA: There's no pH control in the sprays, 10 are there? 'll MR. SCHULZ: There's no pH control in the spray. 12 You'll see in a slide we did evaluate the impact of putting 13 this water into the spray, into the containment and what it 14 would have affect on the pH, and it is minor and 15 insignificant. 16 CHAIRMAN BARTON: Terry, this water level, less l l l 17 109 foot elevation -- how many hundred thousand gallons is 18 that? 19 MR. SCHULZ: That's 300,000 gallons. 20 DR. FONTANA: About 45,000 cubic feet. 21 MR. SCHULZ: We normally flood up to about 107 22 foot elevation, but we don't flood all the volumes to get to 23 that level. There's -- the PXS rooms and the CVS rooms 24 don't normally flood. 25 If we do flood all the volumes, you're down around I l () ANN RILEY & ASSOCIATES, LTD. I Court Reporters -1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 -(202) 842-0034 i

246 1 the 103 level -- /I 2 -DR. FONTANA: Okay. 3 MR. SCHULZ: -- when you get like a wall-to-wall 4 flood. 5 DR. FONTANA: Yes. 6 MR. SCHULZ: So, you go -- you would go from like 7 the 103 level up to the 109 level by adding 300,000 gallons 8 of water. 9' So, it may be a little confusing. If you're used 10 to thinking of our re-circ level as 107 plus and we add that 11 much water, you know, does it really make sense that we're 12' only going up a foot or two, and there's other volumes that 13 we would end up flooding in this situation. 14 I was just saying chat the amount of -- the (O ,/ 15 benefit of the system is somewhat dependent on the sequence 16 of events and the timing. We've done some sensitivity 17 studies of starting at one hour, hour-and-a-half, two hours 18 after the sourc-e term that we used in the SSAR. 19 You get some variation but not a lot in the 20 benefit of iodine reduction. 21 We had to tried to assure ourselves that the 22 addition of this system doesn't cause any serious adverse 23 problems. 24 One of the things that we looked carefully at, was 25 it possible to have an inadvertent spray, and as I showed O ANN RILEY & ASSOCIA7TS, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

247 1 you, there's these three valves that have to be realigned, 2 mis-positioned, open up in order to cause spray. So, we 3 have concluded that that's not credible. 4 DR. APOSTOLAKIS: What kind of probability would 5 you think that event has? 6 MR. SCHULZ: Totally insignificant, beyond 7 calculation. 8 We've got one lock-closed manual valve that's a [ 9 containment isolation valve. So, that's got a very high 10 degree of assurance. 11 Typically, that one valve is enough to not assume 12 'that -- in design basis space -- that a system is realigned. 13 However, that by itself would not give you a insignificant 14 probability. 15 But combined with these other two, in my 16 understanding of the PR4, it wouldn't even be modeled in the 17 PRA. It would be thrown out by screening-type criteria. 18 So, I don't know what the number would be, but in my 19 opinion, it would be completely insignificant. 20 DR. SEALE: Is this the moral equivalent of *,he 22 conservatism that are in the thermal hydraulics 22 calculations? 23 If-I take a little over 1,000 gallons per minute 24' 'and divide it into 350,000 gallons in that tank, I get over j 25 five hours of capacity, and you indicate you have three l i -ANN RILEY & ASSOCIATES, LTD. Court Reporters-1025 Con:.ecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

248 1 hours. () 2 MR. SCHULZ: Yes. 3 DR. SEALE: Is that just conservancy? 4 MR. SCHULZ: That's just conservatism, yes. It 5 could run -- '6 DR. CARROLL: The tank had already been sized. 7 MR. SCHULZ: The tank's already been sized. 8 DR. SEALE: I appreciate it, but it's more than L 9 five hours, it's not three hours. 1 10 CHAIRMAN BARTON: In three hours you put like 11 186,000 gallons. 12 DR. SEALE: Yes. 13 MR. SCHULZ: Yes. 14 OR. SEALE: So, it is the moral equivalency of ) 15 neglecting the heat capacity in the containment pressure 16 calculation. 17 MR. SCHULZ: But the containment pressure, I don't 18 think is -- 19 DR. SEALE: That's another issue we dealt with the l 20 other day. 21 MR. SCHULZ: Right. The procedure would be to l 22 keep running that water in there. So, if the water is ~ 23 really available and it doesn't cause the water level to go R24 above the 109, you'd really get your four or five hours. 25 DR. SEALE: Yes. 1 l-I ANN RILEY & ASSOCIATES, LTD. i s-- _ Court Reporters i 1025 Connecticut Avenue,-NW, Suite 1014 i Washington, D.C. 20036 (202) 842-0034

249 1 DR. FONTANA: What do the operators require to () 2 start this thing up? 3 MR. SCHULZ: Say again? 4 DR. FONTANA: What signals? 5 CHAIRMAN BARTON: It gets you into the severe 6 accident management guideline. 7 MR. SCHULZ: This is a very key input into getting 8 into the severe accident management guidelines, and there's 9 a number of steps that you start taking -- l 10 DR. FONTANA: Okay. l 11 MR. SCHULZ: -- once you get into here in terms of 12 trying to get the reactor system pressure down to avoid a 13 high-pressure melt-type sequence, to dumping the IRWST to 14 establish the ex-vessel cooling, and another action in that () 15 list'would be to line up the spray system and to -- so that 16 it can be used when it's judged appropriate to use it. c l. -17 DR. FONTANA: Now, if your thermo-couples don't l 18 work, you don't run. Is that correct? 19 MR. SCHULZ: Not by procedures. If you had no 20 indication of high core exist thermo-couple temperatures, -21 there's other temperature indicators in the hot legs. You 22 know, you're into something -- 23 DR. CARROLL: You've also got radiation L 24 monitoring. 25 MR. SCHULZ: You've got radiation monitors, ) ANN RILEY &-ASSOCIATES, LTD. / Court Reporters 1025' Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

250 1-although I don't know how -- () 2 CHAIRMAN BARTON: Is there a dome monitor in this 3 containment, radiation dome monitor? 4 MR. SCHULZ: There's'several -- I don't know if 5 they're actually located in the dome, but they're in the 6 atmospheric space. 7 DR. CARROLL: I think Reg. Guide 1.97 tells you it 8 has to be up there. 9 CHAIRMAN BARTON: You have to have one up there,- 10 'right? 11 DR. CARROLL: I think so. 12 MR. SCHULZ: So, we think that,'in our minds, 13 'we're relying on these core exist thermo-couples to give us 14 a very clear signal to the operators of when to do it, when () 15 -not to do it, so that we can not get into situations where 16 it -- the operators might inadvertently decide, oh, gee, I 17 think I need it and turn it on in design basis accidents. 18 So, the clear and unambiguous indication is an important 19 - part of this judgement that the inadvertent spray during 20 design basis-type accidents are not a credible event. 21 CHAIRMAN BARTON: Does the staff agree that it's '22- 'not credible'and requires misalignment of three valves for 23 inadvertent containment spray?

24~

-MR. SNODDERLY: This is Mike Snodderly. 25 'I don't'know if I would use the word " incredible," l ) ANN RILEY & ASSOCIATES, LTD. Court Reporters i ~1025 Connecticut Avenue, NW, Suite 1014 Washington', D.C. 20036-(202) 842-0034

251 1 because we didn't do the analysis or the PRA, but we felt () 2 that it was sufficient to preclude the need for -- 3 CHAIRMAN BARTON: The reason I ask is because, in 4 a discussion on leak before break in feedwater, it requires 5 the same kind of thing, misalignment of several valves, get 6 the water hammer, and you guys thought it was credible. So, 7 I just -- that's why I asked. 8 DR. CARROLL: I think I would strike the word 9 " credible" from our nuclear vocabulary. It has caused a lot 10 of trouble over the years. 11 DR. APOSTOLAKIS: Highly unlikely. 12 CHAIRMAN BARTON: Highly unlikely. 13 DR. CARROLL: That sounds better. 14 MR. SCHULZ: Other design basis evaluations we ( 15 performed were evaluation of boron dilution -- and again, 16 key to this evaluation was the going-in assumption, based on 17 the previous page, that spray -- inadvertent spray is not an 18 event that you have to consider in design basis space, it's 19 - only used in severe accident. 20 In severe accidents, the core is severely damaged, 21 its geometry is changed, and the need for boron is not a 22 requirement anymore. So, as a result, boron dilution is not 23 a concern, and we have not evaluated it. 24 DR. CARROLL: This change of core geometry is 25 .always in the direction of making the core less reactive? ( ANN RILEY & ASSOCIATES, LTD. A Court Reporters 1025 Connecticut Avenue, NW,' Suite 1014 Washington, D.C. 20036 (202) 842-0034 l

252 1 MR. SCHULZ: That's my understanding. I'm not an ( 2 expert in that area, but there also tends to be less space 3 for water to get, you know, in -- that's part of it. 4 Containment pH we looked at, and we actually did a 5 little sensitivity study where w'e put in 300,000 gallons of 6 water and looked at our long-term pH calculation, and the i 7 indications were that the pH would increase but only very 1 1 8 slightly, and as a result, we don't think there's any issue 9 w; th re-evolvement of iodine. l 10 DR. SEALE: Basically no problem. l 11 MR. SCHULZ: No problem. 12 DR. CARROLL: And in your modeling, you did have 13 the tri-sodium phosphate. 14 MR. SCHULZ: We had tri-sodium phosphate. (O ,/ 15 DR. CARROLL: It is buffered with tri-sodium 16 phosphate as you're adding this neutral water. 17 MR. SCHULZ: Right. We attempted to account for 18 the sulfuric acid from cable' degradation, nitric acid from 19 the air. 20 DR. POWERS: I think, at one time, I asked what G 21 value you're using for your nitric acid in the air. 22 MR. SCHULZ: I don't know the answer to that. I 23 didn't do the calculation myself. I'm not aware. 24 DR. POWERS: Do you know where that calculation 25 was done? l r ANN RILEY & ASSOCIATES, LTD. \\- Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

253 1 MR. SCHULZ: Fauske & Associates did the () 2 calculation for us. I think it was made available for staff 3 review and they did look at it. I don't know - far as I 4 know, there was no -- they considered there was no problem 5 . with it, but I don't know what the extent of their review 6 was. 7 DR. POWERS: You indicated that putting in 300,000 8 gallons of spray increases the pH? 9 MR. SCHULZ: No. 10 DR. POWERS: It decreases. 11 MR. SCHULZ: Decreases the pH, yes. I didn't 12 really say that there, but -- 13 DR. CARROLL: Yes, you did. 14 CHAIRMAN BARTON: Just said changes. 15 DR. CARROLL: Decreases. 16 MR. SCHULZ: No, decreases. It's kind of removed 17 from the pH there, 30 days are in the middle, so it's -- 18 yes, you're right, I did. It does decrease it. 19 DR. POWERS: Phosphate interacts with a lot of 20 things to form precipitates. Is there a concern about the 21 phosphate loss, consequently a loss of buffering capacity, 22 due to interactions with lots of things -- concrete, steel, 23_ iron, contaminants, things like.that? l 24 MR. SCHULZ: I don't know the answer to that 25 question. I would have to ask that if you wanted an answer. I ANN RILEY & ASSOCIATES, LTD. g i - Court Reporters ( 1025 Connecticut Avenua NW, Suite 1014 L Washington, D.C. 20036 l (202) 842-0034 l'

254 1 DR. CARROLL: Put that on the Dudley list, Dana? () 2 DR. POWERS: I think it's a back-of-the-envelope 3 calculation, probably not a very big-effect, as long as the 4 phosphate solution is not in contact with concrete. 5 MR. SCHULZ: Well, there's coatings on concrete. 6 AP600 has a lot of steel modules. So, it tends to have a 7 bit less concrete than operating plants does, although there 8 is still some 9 DR. POWERS: I assume most of the sumps are 10 steel-lined, aren't they? 11 MR. SCHULZ: The sumps are steel-lined, but we do 12 float up the loop compartment. 13 Now, the loop compartment walls are steel. The 14 floor, I believe, is concrete. I () 15 DR. POWERS: Coated. Some sort of coating on it? 16 MR. SCHULZ: Yes. Yes. And the floor would be 17 thick kind of a epoxy on the floor. 18 DR. POWERS: I suspect it's difficult to be -- to 19 do the calculation in a way that persuades the more 20 skeptical, but I'll bet you that, in reality, that you get 21 some precipitation, but it's not enough to change, got 22 enough -- in there to -- a lot of coveralls. 23 MR. SCHULZ: Yes, there is a lot. 24 We have committed to a number of ITAAC test 25 inspections -- one, just to visually inspect that there are O ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 i (202) 842-0034

[ 255 1 nozzles in the containment, in the spray headers. (,s) 2 There's a verification that the water fire 3 protection pumps have adequate had flow, the water tank has 4 adequate volume, and we've also added, more recently, a 5 inspection to -- for valves that would be used to isolate 6 the spray header from the normal fire protection system so 1 7 that they can be aligned during normal operation and provide 8 the desired separation and avoidance of inadvertent spray. l l 9 DR. SEALE: I remember several years ago, many 10 years ago now, that in connection with an experimental 11 facility that was steel-lined, a concern for electrical 12 shock hazard was expressed and, let's say, administrative 1y 13 cleared, as I recall, and then, as it turned out later, 14 someone, in fact, did get fatally injured from an electrical 15 shock. 16 Is there any -- has there been any concern for 17 these large rooms with essentially steel linings as being a 18 peculiarly severe electrical hazard? 19 DR. CARROLL: Not if they're grounded, I don't 20 think. 21 DR. SEALE: These were grounded, but -- I'm just 22 curioua. It was just something that was in the back of ng-23 mind. 24 MR. SCHULZ: I have not heard any concern raised, 25 but I don't really -- I'm not really an expert in that area. ,~. ( ANN RILEY & ASSOCIATES, LTD. 4 \\# Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

256 1. Are there any other questions? () 2 DR. SEALE: Is there any problem along those lines 3 that you're aware of, staff? 4 MR. SNODDERLY: No, sir. 5 DR. SEALE: Okay. 6 MR. SNODDERLY: That wasn't something we 7 considered. 8 DR. CARROLL: I don't think there's any history in 9 the nuclear industry of that sort of thing. 10 CHAIRMAN BARTON: Most of those compartments are '11 basically concrete painted, shield or painted concrete 12 compartments. 13 DR. SEALE: You're not working a steel tank. 14 CHAIRMAN BARTON: Steel-line compartments I don't ) 15 think are prevalent in today's design. 16 DR. CARROLL: Well, your torse is a steel 17 container. I 18 MR. SCHULZ: The two-loop plants that are 19 operating in the United States have steel containments. 20 CHAIRMAN BARTON: Oh, yes. 21 MR. SCHULZ: And the ice containments, I think, 22 are steel. 23 CHAIRMAN BARTON: I think Bob's question was more 24 towards %scompu tments -- at least our understanding was 25 you're talking about sub-compartments within containment s ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite in14 Washington, D.C. 20036 (202) 842-0034

257 1 that had steel-lined walls or something. I () 2 DR. SEALE: Yes. You're truly grounded in 3 something like that. I mean there's a good path to ground i 4 if you ever ma. age to come in contact with anything. 5 MR. SNODDERLY: The Mark I containment, that type 6 of containment, you've got the steel torse, and I can't 7 recall any incidents of electrocution. 8 DR. SEALE: Okay. 9 CHAIRMAN BARTON: Any other questions of Terry? 10 [No response.] 11 CHAIRMAN BARTON: Looks like not. Thank you. 12 DR. CARROLL: I think he got off easy today. 13 MR. SCHULZ: You'll have another chance here. I 14 DR. POWERS: Is the staff going to have an /3 () 15 opportunity to comment on what they did to review the nitric 3 16 acid production? 17 If you have a G-value of .01, then, yes, you're 18 not going to change the pH at all. If you use a G-value of l 19 5, you'll probably change the pH by a lot. So, the question 20 is what value was used? 21 MR. SCHULZ: We could get an answer to that. 22 MR. McINTYRE: We should be able to call back and 23 find that. 24 DR. POWERS: It's a straightforward calculation. 25 You need the dose to the atmosphere, and you need the amount l '( 1 ANN RILEY & ASSOCIATES, LTD. k' Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 2003u 1 (202) 842-0034 l l

258 1. of-time, and you need a G-value. 2 CHAIRMAN BARTON: Are you taking that on as an 3 action item, Brian? 4 MR. McINTYRE: Yes. 5 MR. SCHULZ: We performed an evaluation which we 6 reported in a WCAP on adverse systems interaction for AP600. 7 This was a very interesting exercise evaluation. 8 There's not exactly a rule book on how to do this 9 kind of thing, and we found that, for the most part, we had 10 done,. piecemeal-wise, a rather good job in finding adverse 11 interactions, but we had not done a very good job in 12 describing that and conveying that information. 13 So, a lot of what was in this WCAP was pulling 14 together information out of different areas of our design () 15 and analysis and presenting them in a systematic fashion to 16 explain what has been done or hasn't been done. 17 There were three basic types of interaction that 18 we looked for -- what we call functional interactions -- 19 these are thermal hydraulic kind of things, two different 20 systems running at the same time that might somehow 21 interfere with each other -- human intervention interactions 22 -- these are more of the errors of commission in most cases, 23 possibly cognitive errors, and the spatial interactions. 24 These are hazard-induced fire, flood, that kind of thing, j 25 that could possibly affect multiple systems. [~'[ ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 i Washington, D.C. 20036 (202) 842-0034

259 1 We did go through and try to look at both the 2 passive, safety-related systems and the active, 3 non-safety-related systems, both in combinations of act of 4 interfering or interacting with passive, as well as between 5 passive systems. 6 DR. CARROLL: I'm curious about something, 7 probably for the staff. Is this the first time a study as 8 comprehensive as this one has been done on a new design? 9 MR. HUFFMAN: This is Bill Huffman, Projects. 10 I don't know the answer to that question. I'm 11 getting feedback here for the evolutionary designs that such 12 a similar study was done. I don't know how extensive it 13 was. 14 DR. CARROLL: Why don't I remember that? I guess 15 I'm getting old. 16 DR. SEALE: Well, I know Carlisle Michelson had 17 quite a few questions along these lines. 18 DR. CARROLL: Yes. I think the study Westinghouse 19 has done would have gone a long way to making Carl happy. 20 MR. HUFFMAN: The additional feedback I'm getting 21 is that, in the evolutionary designs, it was in response to 22 one of the USI-GSI generic issues for interaction. So, it 23 may not have been as comprehensive. 24 DR. CARROLL: Thank you. 25 MR. SCHULZ: What I'd like to now do is to go O ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 84 b34

260 1 through these three different types of interactions and try () 2 to explain what we did do. 3 In terms of the functional interactions, we tried. 4 to look at the potential or tried to discover potential 5 adverse interactions, and the underlying basis for that was 6 our understanding of AP600 system behavior, and that 7 understanding has a lot of separate activities that form 8 that understanding, going back to detailed hand-type 9 calculations and evaluations, small-scale-type research that 10 was done on AP600 features, larger separate effects testing 11 that was done on AP600 features, and probably very important 12 was the interval systems testing at SPES and OSU, where we 13 actually did run some of the sequences with both active and 14 passive systems functioning at the same time, as well as, 15 obviously, the passive systems working together. 16 A lot of work and thinking goes into the DBA 17 analysis to consider, and that's one of the fundamental jobs 18 of the analysts that do the DBA analysis, is to think about 19 what is the worst set of conditions. 20 So, they do -- historically have done a lot of 21 thinking of how can the feedwater system malfunction, how 22 can these other systems malfunction that are non-safety 23 systems and adversely affect the course of an accident. 24 Now, AP600 throws a few wrinkles into that, 25 because we have a little different mix of systems, but the o f ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

F 261 1 fundamental part of DBA analysis is to do some of this 2 thinking. 3 The PRA success criteria thermal hydraulic 4 analysis is another large body of analysis that was.done and 5 has some of the same objectives. 6 More analysis was done in support of the ERGS. 7 So, together, this analysis, testing, and thinking l 8 about these -- the way the systems perform form the basis 9 for our understanding of the plant. 10 Now, what we do with that understanding? 11 For this evaluation, we tried to put a matrix 12 together of systems and -- active systems and basically 1 13 passive systems or functions and then tried to look at where j 1 14 we thought there might be a potential interaction, and where I (k 15 you see these numbers, these are actually section numbers 16 out of the WCAP, and so, in section 2.2.1, we basically 17 discuss the potential of reactor coolant pumps to cause 18 interactions with the core, core make-up tanks, and passive 19 RHR. 20 We didn't consider in the other areas potential 21 interactions, and again, this was based on our understanding 22 of the plant. 23 I'm not going to through this whole table. 24-There's a lot of information that's in WCAP. I do have 25 basically'an example to talk about, and that happens to be -[~D AJUJ RILEY & ASSOCIATES, LTD. k/ Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

( 262 1 the reactor coolant pump item. () 2 DR. APOSTOLAKIS: Did you consider potential 3 interactions among active systems? 4 MR. SCHULZ: Not explicitly, but when we were -- 5 in this review. 6-I think there was a less concern -- I think the 7 concern as expressed by the staff was you have.-- was the 8 ' passive systems, because they are the primary defense in 9 both -- of course, in DBA space, they are the defense that 10 was relied upon to keep the plant safe. 11 In the PRA, they are the primary defense, provide 12 most of the protection of the plant. If those things work, 13 you're okay. 14 There was also this concern that, gee, passive () 15 systems are sensitive, small DPs, may be more subject to 16 interactions. 17 So, I think those two factors led us to focus on 18 the passive systems and whether or not active systems could 19 adversely interact with them or between themselves, and we 20 haven't really looked at active to active. 21 DR. APOSTOLAKIS: Or between themselves. You mean 22 what? 23 MR. SCHULZ: Between core make-up tanks and f24 passive RHR. 25 'D'L APOSTOLAKIS: I see. (( ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 L Washington, D.C. 20036 (202) 842-0034 _ _ = _

I 263 1 MR. SCHULZ: That kind of thing. And that's the () 2 next table I was going to show you. We did a similar kind o 3 matrix for the passive features, which basically just lists 4 the same systems on -- across the top and down below, and 5 then to discuss the potential for interactions. 6 There's a few of them that we basically excluded, 7 but most of them -- as you see, this is all filled in up 8 here -- we discussed in the WCAP. 1 9 DR. APOSTOLAKIS: So, what was your conclusion? 10 MR. SCHULZ: The conclusion -- well, two more 11 slides. 12 DR. APOSTOLAKIS: Okay. But even interactions i 13 among active systems -- I mean the guys who developed the 14 event trees must have taken them into account. If you have ) 15 more than one active system in an event tree, you really 16 have to look for potential dependencies, right? 17 MR. SCHULZ: Well -- 18 DR. APOSTOLAKIS: So, maybe it was not part of 19 this study, but -- 20 MR. SCHULZ: Absolutely, dependencies, if this 21 system needs this one to work, and then I suppose the 22 converse of that is, if this one doesn't work, that one 23 doesn't work. So, absolutely. 24 DR. APOSTOLAKIS: What if they share -- 25 MR. SCHULZ: Yes. ^ (d-) ANN RILEY & ASSOCIATES, LTD. Court Reporters x 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

264 1 DR. APOSTOLAKIS: -- components and all of this. () 2 MR. SCHULZ: Yes. From that point of view, the 3 PRA -- that's one of the basic fundamental things that's 4 done in the PRA, is to look for those interactions. 5 DR. APOSTOLAKIS: This study, then, was sort of '6 -special because of the introduction of the passive systems, 7 you had to do this excellent work. 8 MR. SCHULZ: Yes. And to see if the - 'to try to l 9 look for something that might have been missed in everything 10 else you do. 11 DR. APOSTOLAKIS: Right. 12 MR. SCHULZ: This matrix here is primarily looking 13 at Chapter 15 analysis, and again, there's multiple pages of 14 this in the WCAP, and what it's looking at is listing the 15 active systems and assumptions made in the SSAR, and 16 basically, what this table summarizes is that there are a 17 number of active systems in PWRs that historically -- and 18 with AP600, also -- are potential adverse interaction 19 situations. Excessive main feedwater is a good example. 20 And there are valves and controls and interlocks 21 to minimize the potential, to prevent those kind of 22 interactions I 23 AP600 typically has done maybe a little bit more 24 in that area because of our -- in some cases, the passive 25 systems allows us to automatically shut off start-up O ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034 L _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ = - _ _

265 1 feedwater, because it's not the safety-related way of '2 cooling the' reactor in a transient. 3 So, if things get a little out of whack or start 4 looking like threatening core cooling, we can turn off 5 start-up feedwater. It's a very dangerous thing to do in a 6 plant where that is your safety-related means of cooling. 7 The same thing with CVS make-up -- that's our 8 high-pressure make-up, and so, if we have a potential 9 pressurizer overfill situation developing, we can shut off 10 the CVS without worrying too much that we're defeating our 11 safety-related means of make-up. 12 DR. FONTANA: What are the entries again -- N.2, 13 A.2, that sort of thing? 14 MR. SCHULZ: These are notes in the WCAP that -- 15 DR. FONTANA: Oh, okay. 16 MR. SCHULZ: -- basically tell you something about 17 the assumptions made in the safety analysis relative to this 18 event versus this feature. 19 The next slide had a little example of 20 active-passive kind of interaction and sort of illustrates 21-the approach and what we did in these -- in little sections 22 that dealt with -- so, you'll find a section in the WCAP on 23 reactor coolant pumps, which is 2.2.1, and it basically goes 24 through a function discussion, what the reactor coolant 25 pumps do. O ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 7 (202) 842-0034

T: 266 1 Of course, they circulate reactor coolant through () 2 the reactor coolant system, through the core, and during an 3 event, their operation tend to increase the heat transfer 4 out of the core, which is usually good and sometimes can 5 actually cause interactions by itself. 6 Then.we, understanding the context of the 7 component you're talking about, thought about the potential l 8 interactions as we identified in that table, and there were l 9 like three of them. 10 One of them was core cooling, and what were 11 thinking about here was, in particular, the small LOCA 12 situation of running reactor coolant pumps during a small 13 LOCA and then, possibly with the loss of the reactor coolant 14 pumps, get core uncovery or something actually outside the () 15 design basis, and we deal with that in AP600 with automatic 16 safety-related reactor coolant pump trip. 17 So, in a safety injection signal, we stop the 18-reactor coolant pumps, and that prevents this adverse 19 interaction, whereas in operating plants, they don't trip 20 the pumps, they allow -- rely on the operators to trip them 21 when they think it's appropriate. 22 The operation of the reactor coolant pumps can 23 adversely -- or degrade to some degree the circulation -24 through the core make-up tanks. Again, we automatically 25 trip the reactor coolant pumps-when we actuate the core O ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

267 1 make-up tanks to prevent that interaction. () 2 ' Operation of the reactor coolant pumps enhances, 3 increases passive RHR heat removal. Again, depending on the 4 situation, that can either be good or can lead to some 5 adverse interactions. During a steam line break, operation 6 of the reactor coolant pumps tends to make the accident 7 worse. 8 We do get into safety-related tripping of the 9 reactor coolant pumps on a excessive cool-down kind of 10 signal, which minimizes this effect, and then basically the 11 passive RHR transitions from a forced circulation to a 12' natural circulation mode, flows down, and so, the 13 interaction is minimized. 14 So, in this particular case, in going through this () 15 process, there were potential adverse interactions. 16 They had already been dealt with in the design 17 basically by automatic reactor coolant pump trip, which was 18 a part of the design, and that the design basis accidents 19 and PRA evaluations had accounted for this, and in fact, you 20 see in the PRA -- was discussed yesterday in the level one 21 that the core make-up tank / reactor coolant pump trip is 22 typically' treated as a -- both are necessary to get core 23 make-up tanks 24 So, kind of in summary for the functional 25 interactions, a number of active / passive adverse systems ] ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

268 1 interactions were identified. Many of them are the same () 2 kind of interactions you have in today's plants -- i.e., 3 excessive feedwater kind of thing. 4 Some are unique to AP600, like the reactor coolant 5 pump that I talked about. All of them are addressed, that 6 we identified, in the DBA and the PRA analysis, and again, 7 some of them require mitigating features like feedwater 8 isolation or reactor coolant pump trip. 9 We did not identify any significant 10 passive-passive interactions. 11 Now, there were some there. They are dealt with 12 in the testing and the analysis. So, we don't do anything 13 in terms of trying to control it by operator action or 14 basically interlocks and control featurec. () 15 We have identified the potential interaction and 16 quantify that in the analysis of the plant. 17 Probably the most challenging aspect to this whole 18 study was the human factors, human intervention. As you 19 heard yesterday in our PRA level one discussion, the PRA 20 accounts for, quantifies operator errors where the operator 21 fails to take an action. 22 So, they quantify that kind of interaction, but 23 they don't really quantify errors of commission, where the 24 operator takes the wrong action. 25 As a result of that -- of PRA -- and also the O ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

269 1 fact, as you saw yesterday, that AP600 is relatively () 2 insensitive to operator actions, must less sensitive than 3 operating plants. 4 So, what we looked at in this study was primarily 5 cognitive-type errors, errors of commission that we tried to 6 look at. 7 In talking with our human factors experts, they l 8 advised us that the kind of things that can lead to those 9 problems are maybe three, three-fold, as they're outlined in 10 the WCAP -- unfortunately, I didn't quite get them up here 11 -- goal conflict kind of errors. 12 DR. APOSTOLAKIS: What conflict? 13 MR. SCHULZ: Goals, conflicts in goals, like what 14 happened TMI, where you had the high head pumps running and () 15 you wanted the pumps to run, but you were overfilling the 16 pressurizer. 17 So, the pumps running were -- there was a goal l l 18 conflict there. That's one way of looking at it. 19 Now, AP600, with the passive systems, eliminates 20 some of those fundamental goal conflicts from the plant. 21 The passive systems don't tend to cause some of 22 those events that -- goal conflicts that the active systems 23 do, or we can, like I say, isolate charging pumps or isolate 24 start-up feedwater to eliminate that goal conflict, whereas 25 in operating plants, those are your safety-related means and [~' ANN RILEY & ASSOCIATES, LTD. \\-- Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

270 1 you've got to be careful about stopping them. () 2 A second potential cognitive error you can get 3 into with too much information, too little information to 4 the operators. 5 Now, that's not something we can explicitly deal 6 with here. 7 'That's a objective we've taken on, and it's 8 described the SAR in Chapter 18 for the man-machine 9 interface design of the plant, which is ongoing and in the 10 future, to provide the right amount of information and in 11 the right way, in the right priorities. 12 Another thing that can cause cognitive errors is 13 knowledge-based-type decisions, and again, Chapter 18 takes 14 on commitments for the structure of the ERGS, the functional D(,) 15 -- the task-based-type decisioning, decision-making, the 16 symptom-based ERGS are a primary defense against that kind 17 of a problem. 18 So, what did we do? We basically took the 19 potential adverse interactions that we identified in the 20 first part of this study, the functional adverse 21 interactions, and we looked at each of those, and we asked 22 ourselves some questions, and those three questions are kind 23 of outlined -- 24 DR. APOSTOLAKIS: You have a last bullet there l 25 that says safety versus economic consequences. l ANN RILEY & ASSOCIATES, LTD. 1 \\ Court Reporters i 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

271 1 I don't see what the designer can do about it. I I 2 mean that's really for the owner and operator of the plant, 3 the licensee, to make sure that we don't have conflicts 4 there, but you guys cannot do it. 5 MR. SCHULZ: No, we can. 6 DR. APOSTOLAKIS: What can you do? 7 MR. SCHULZ: We did. By making the design so that 8 it minimized -- this is kind of a goal conflict again, and 9 one of the key examples is the feed-and-bleed cooling. You 10 know, the goal is to cool the core and you're running out of 11 options, you know, that is your kind of last resort option. 12 However, if you do turn that on, you mess up the 13 containment. So, oh, gee, what do I do? 14 In AP600, we think we have done something to () 15 minimize that, You dcn't eliminate it but minimize it by 16 design. 17 One, we're, in our minds, less likely to get into 18 that situation, because we have more ways of cooling the 19 core before we get into feed-and-bleed. 20 We have start-up feedwater, main feedwater, which i 21 a current plant's got to have. We have passive RHR, which 22 is an extremely reliable passive system. If it works, you l 23 don't need to feed-and-bleed. So, that's one step. 24 The other step is that, if you get into l 25 feed-and-bleed cooling, we can get into that with almost no l l l l /~ ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

I 272 1 containment consequences, assuming the r.ormal RHR pum, () 2 works, and that is the normal procedure. 3 If you get into ADS and you only open the first 4 three stages, which is when you initiate bleed out of the 5 system, that's all you're really -- the operator is 6 committing to. 7 He knows, in his current plant, that if he opens 8 up the power-operated relief valve, he is going to very 9 quickly burst the rupture disk out of the PRT and he's going 10 to get steam into the containment. 11 AP600, we have this half-a-million-gallon tank, 12 and the operator will know from the design and analysis 13 anyway that if he gets into that situation and gets his 14 normal RHR pump running, he won't steam the containment. ) 15 So, now, yes, if that pump fails, then he gets into there. 16 So, we think we've done something along those 17 lines. You can debate about how important that really is, 18 how significant it is. 19 DR. APOSTOLAKIS: That's fine. We try to avoid 20 situations where the operators would have these conflicts. 21 MR. SCHULZ: Yes. 22 DR. APOSTOLAKIS: Did human factors engineering do 23 anything to you that you found useful? 24 MR. SCHULZ: That's a loaded question. 25 In this effort here, the discussion about what can I ) ANN RILEY & ASSOCIATES, LTD. \\d Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

273 1 lead to a cognitive error pretty much comes out of human () 2 factor kind of considerations in terms of the goal 3 conflicts, too much, too little information, the 4 knowledge-based decision, and then how we're trying to deal 5 with that. 6 Now, some of it we can't do anything about now, 7 it's a commitment for the future in terms of the control l 8 room -- i l 9 DR. APOSTOLAKIS: That's not really human factors, 10 though, but anyway, I see what you mean. But your design of 11 the control room, perhaps, was influenced by human factors i 12 engineering, right? 13 MR. SCHULZ: Oh, tremendously, and that's still 14 going on as the details go on, but yes, yes. () 15 DR. APOSTOLAKIS: I remember. 16 MR. SCHULZ: So, there are a number of tables like 17 this that are in the WCAP again, and there's a couple 18 questions that we ask for each of these potential adverse i 19 interactions that we identified in the functional 20 interaction part of the document. l l 21 The first question was, does an opportunity exist 22 for the operator to make an error based on the procedures, 23 and we had the ERGS that we looked in this part of the j 24 study. 25 So, in case of the reactor coolant pump versus f~3 ANN RILEY & ASSOCIATES, LTD. \\m / Court Reporters 1025 Connc-cticut Avenue, NW, Suite 1014 l Washington, D.C. 20036 (202) 842-0034 Il m _.._.______.m_

I 274 ( l 1 core cooling, we said no, an opportunity doesn't exist, () 2 primarily because the -- first of all, the pumps trip 3 automatically, so that the operators don't have the need and 4 possibly make the error of not tripping them. There's also 5 reactor coolant pump restart criteria that avoids adverse 6 interactions in a recovery situation. 7 The second question was, are there safeguards 8 against the human error, and again, in this case, the pumps 9 are tripped automatically, and that's a safeguards -- the 10 ERGS also provide a bit of a safeguards on the restart. 11 A third question is the adverse interaction 12 modeled in the PRA, and in this case, you're really talking i 13 aber,. the restart is not modeled. The tripping of the pump 14 acteally is modeled, but it's more in conjunction with the () 15 core make up tank operation. 16 DR. APOSTOLAKIS: Okay. 17 MR. SCHULZ: And then there's kind of a 18 conclusion, which is aimed at, you know, is there a concern 19 with human intervention? 20 DR. APOSTOLAKIS: Well, I think this could have 21 been input to the PRA. I mean the PRA is not -- you said 22 that they didn't do it. I mean PRA doesn't do -- PRA 23 doesn't do anything. I mean it depends on who does it and 24 what they decide to include. I 25 CHAIRMAN BARTON: George, I'm surprised at you. ( ANN RILEY & ASSOCIATES, LTD. l \\ Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

275 1 PRA doesn't do anything. (" h ( ) 2 DR. POWERS: It's a quote that will live to haunt 3 him. 4 DR. APOSTOLAKIS: But it is true that the PRA that 5 was presented to us yesterday does not include errors of 6 commission, and again, you have to go with the state of the 7 art. I mean if -- 8 DR. CARROLL: I think we've got a cart and horse 9 situation, too. The PRA predates this effort by a lot, 10 doesn't it? 11 MR. SCHULZ: It predates this WCAP, yes. 12 DR. APOSTOLAKIS: .Now, the other thing is, though 1 13 -- well, I mean this qualitative analysis, you know, given 14 the state of the art, the current state of the art, is 15 probably good enough. l 16 Again, I have a problem with the word " credible." ) 17 -I mean, yesterday, we were given probabilities on the order 18 of 10 to the minus 3, 10 to the minus 4, 10 to the minus 5. 19 So, there is no credible concern means, now, what, that you 20 are below that ? i l 21 MR. SCHULZ: This is obviously qualitative. 2? DR. APOSTOLAKIS: I understand. l 23 But also yesterday we had situations where yes, I l 24 auttmatic actuation failed, now the operators had 10 minutes 1 25 or 20 minutes to act.. l ,\\ { ) ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 I (202) 842-0034

I 276 1 Here, though, you say, if there is a provision for () 2 automatic actuation, then that's a safeguard against human 3 error, which is philosophically a little bit at odds with 4 the discussion yesterday, because the human error -- human 5 action yesterday came into the picture after the automatic 6 system failed, whereas today you're saying, if there is an 7 automatic capability, that's a safeguard. 8 So, there are some inconsistencies there. 9 Now, I don't know how important they are, but we l 10 can't keep silent, right? 11 So, that -- I guess that's fine. 12 MR. SCHULZ: Our point of view here was largely in 13 less extreme situations than you get into the PRA, where-you 14 have multiple things going wrong. ( 15 Now, you do have to consider that in the ERGS, in 16 the whole design of the human factor, man-machine interface. 17 We were looking here for more can the operatora do 18 things in either design basis accidents or more likely 19 things that would cause a problem all by itself? 20 So, wnen we use the word " credible" here, it is, 21 first of all, qualitative judgement kind of thing based on 22 these first three columns. 23 DR. APOSTOLAKIS: I understand. 24 MR. SCHULZ: That's all it is. 25 DR. CARROLL: I guess the one thing that goes into O' ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

277 1 the credible discussion is every operator knows how to () 2 bypass things if he wants to, and we never consider that, 3 but it's something that happens at times. 4 DR. APOSTOLAKIS: That's the real concern, really, 5 ycq, but we don't know how to analyze that. 6 DR. CARROLL: It's fine to say it's an automatic 7 trip, but I can make it un-automatic. 8 DR. APOSTOLAKIS: At the same time, of course, it 9 depends on the operators. They have done things in the past 10 that were innovative and saved the plant, so -- but you're 11 right, that's really the issue, and crazy things have 12 happened sometimes. 13 So, we're hoping ATHENA will tell us how to handle 14 those things, right? () 15 DR. POWERS: Undoubtedly to three decimal points, 16 rigot? 17 MR. SCHULZ: Our conclusion in the human i 18 factor-human intervention part of this study was that we 19 didn't see any potential for significant human adverse 20 interactions, and kind of a summary of why that is so is 21 that the passive features require less either automatic or 22-manual actions for them to continue working. 23 The required actions that -- the actions that are 24 required are automatic, and if they work, then there's l 25 really no need for operator action. If they don't work, l.} ANN RILEY & ASSOCIATES, LTD. l Court Reporters l 1025 Connecticut Avenue, NW, Suite 1014 l Washington, D.C. 20036 (202) 842-0034

278 1 then you get into some of the beyond-design-basis PRA () 2 considerations. 3 And the ERGS are structured ano designed to avoid 4 adverse interactions. 5 I think there was some discussion yesterday about 6 the goal tree monitoring that goes on independent of the 7 operators that are actually managing the plant in an 8 accident situation, and that's, you know, another example of 9 the procedures and how they attempt to avoid cognitive-type 10 errors. 11 The final, third part was actually the most 12 straightforward part of the adverse interaction study, 1.? looking at spatial-type, hazard-induced interactions, and 14 tha studies that are typically done for plants, the fire () 15 hazards, the flooding hazards, missiles, seismic pipe 16 breaks, all these, basically their objective is to look for 17 such interactions, high-energy line breaks on non-safety 18 systems and their impact of jetting and flooding on safety 19 systems, so -- and the PRA does some independent look at 20 some of these things, in particular the fire and floods. 21 So, we basically looked at these hazards analysis, 22 and they all concluded that there weren't any problems with 23 the plant design, and that was pretty much the extent of 24 this part of the study. 25 The kind of underlying reasons why, you know, ) /] ANN RILEY & ASSOCIATES, LTD. \\- ' Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034 l

279 1 there weren't problems in those areas is that the AP600 () 2' design has very effective separation, very sort of 3 block-wise kind of separation, safety division, the division 4 outside containment, non-safety to safety, both. 5 There's less stuff outside of containment, a lot 6 less stuff to worry about. You don't have the train of 7 cooling water, service water, CCW into the plant, into HVAC, 8 into RHR cooling. 9 We don't have continuously operating equipment. 10 So, fire and flood effects are somewhat less significant, 11 because once we get our passive systems working, you don't 12 need power to run equipment anymore. 13 Simplified flood protection -- this actually is 14 related to the passive systems in that we don't have large 15 water supplies outside of containment that are needed to 16 provide safety injection or steam generator feedwater that 17 are located in safety areas that can interact adversely. 18 Sc, we have a very simple, basically exclude large 19 water supply kind of approach to flooding, and we don't have 20 to worry about as much of that as the current plants do, and l l 21 we have done some upgrading inside containment on fire 22 protection, which then helps this whole story of minimizing 23 fire-induced interactions. i 24 I think that's the last slide I had, if you have 25' any questions. a l ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 i Washington, D.C. 20036 (202) 842-0034 i U

280 1 DR. FONTANA: What was the WCAP number you were () 2 referring to? 3 CHA'2 E < BARTON: 14477. 4 MR ~FaZ: Yes. There's a Rev. 1 that's out on s 5 that. l 6 DR. CARROLL: Looks like that's an extra one l 7 sitting there if you want it. 8 CHAIRMAN BARTON: Looks like no further questions, 9 Terry. Thank you. 10 DR. APOSTOLAKIS: Yes, I would like a copy of 11 that. 12 CHAIRMAN BARTON: Does the staff have any 13 comments? 14 MR. HUFFMAN: This is Bill Huffman, Projects. 15 Allen Levin, with the support of -- you know, it 16 was a cross-section of most of the technical review 17 branches, but Allen Levin was the lead reviewer in this 18 effort, and he agrees with Westinghouse that the design in 19 the event of restart and other proceduralized things that 20 might happen beyond what the design is automatically capable 21 of being done are covered in the ERGS and in the design and 22 there aren't any other adverse interactions that they could 23 find. 24 CHAIR"s:</4 BARTON: Okay. 25 Another nice tie today, Mr. McIntyre. You dressed l l I \\ ANN RILEY & ASSOCIATES, LTD. \\ Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

t 281 1-for the occasion. () 2 MR. McINTYRE: Thank you. It's not an engineer's 3' tie. l' 4 CHAIRMAN BARTON: That's why I said you dressed 5 for the occasion. 6-DR. CARROLL: A good-looking tie? Why would you 7 wear something like that? 8 MR. McINTYRE: Well, people have thought this was 9 my NRC tie, because that's actually an eagle in the center, 10 and I've been accused, and I was thinking about ties this

11 morning.

12 We had these AP600 ties made up, and they're 13 wonderful, and one of my tasks in life is to get rid of -- I 14 have about 2,000 of them, and they're not exactly going 15 fast, you can only do so much. I think we've actually given 16 them to the NRC. They fit well within the $25 limit. 17 Actually, they come in two colors. I don't know 18 if they say Westinghouse. They say AP600. I was thinking, 19 since I've got these left, I'll drag a gross of them down 20 and give them to Noel, because they're not violating 21 anything there. 22 Security -- this is in response to Mr. Carroll's 23 and Mr. Barton's comment of, gee, this plant is really going 24 to be'a pain to maintain, and we may have cut down our 25 security force, but our maintenance force is now going to ANN RILEY & ASSOCIATES, LTD. S-Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036-(.202) 842-0034

i 282 1 have to have a security force equal to the security force 1 () 2 that we thought we were getting rid of to let these guys in, 3 and I'm' going to start 4 DR. CARROLL: Plus operators, plus fire 5 protection. { 6 MR. McINTYRE: Yes. I'm going to start on the 7 middle slide. That's always a good place to start,_because 8 it makes a little more sense there. 9 This is the 117-foot elevation, and all these nice 10 things aren't colored in on the ones that I handed out, 11 because I wasn't going to color them all. You can color 12 them in if you so desire. 13 The original design, as you will recall -- and 14 I'll speak mostly to Jay and John, because they were the ) 15 people who had the concern -- is they had a little jail cage 16 drawn around each one of these that required -- because the 17 guy would leave -- the color code is -- on the red side -- 18 is the vital area, the blue shaded in is the protected area, l 19 and what they had before were these little jail cages here, 20 and this one -- right there -- so that if the guy was going 21 to go out to maintain this, he had to go out -- because he 22 was going from the vital area to the protected area, out 23 into the general plant, and then back in again, he had to l 24 have a guard, he had to be searched, he had to be looked at, 25 and you guys didn't like that. I guess that's a fair ~ [~ ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

283 1 statement. 2 So, we'went back, and it turns out that the design 3 you see here is really the design that the designer j j 4 originally had, and he was just tickled pink that you guys j 5 -- I mean I called back and said, look, they have this 6 problem. 7' By the time I got back that night, they had this, 8 because the guy had them in a drawer, and he just pulled -- 9 he liked it better and he got talked out of it. 10 So, after we got over all I-told-you-so's, what 11 we've done is there's a column line right here, and instead 12 of having the jail cages, we're moving to this column line, 13 and it's a floor-to-ceiling -- it's either a steel siding 14 with slots cut in it for ventilation or a wire mesh with 15 intrusion detection. 16 This whole area is then covered with CCTV so that 17 they can watch to see if people are bothering the doors, but I 18 the guy never has to go out to maintain the plant. He'll 19 just go out through these doors and then he can card back in 20 through there, so he never really goes out into the plant. 21 He'll go from the vital area to the protected area back into 22 the vital area again. 23 DR. SEALE: So, essentially, he has a lock in the 24 form of a card to get through the door. 25 MR. McINTYRE: Yes, right. ['} ANN RILEY & ASSOCIATES, LTD. v Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034 1 1

284 1 DR. SEALE: He doesn't have to go through -- 2 ~ MR. McINTYRE: Yes. He's searched when he gets 3' into this area. 4 CHAIRMAN BARTON: He does it one time, then. 5 MR. McINTYRE: Right. He does it one time, and he 6 can maintain that. 7 So, this whole area is covered. It's grating on 8 the floor. This is 19 feet, 3 inches, so there's enough -9 room to do maintenance and get things in and out of the 10 room. 11 You'll see, on this end -- I'm starting on this 12 because -- at this elevation, because the previous elevation 13 doesn't really look significantly different, but to get down 14 to the lower elevation and to the upper elevation, there's a 15 set of stairs right there. 16 So, now, if you go back to the first slide, you 17 .can see that we still have -- getting into the annex 18 building, they still have the jail cage, because that makes 19 sense. 20 We didn't want to -- one is there's too much 21 equipment, and two is you don't really need to, but we 22 couldn't move all these things. We had to move some 23 equipment. 24 If you look at the old drawings to the new 25 drawings, there was some equipment that got moved outside of ANN RILEY & ASSOCIATES, LTD. A Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

285 1-that line. We couldn't move these things. So, this still () 2 has the jail cage, but you're not -- there won't be a lot of 3 access into.there. 4 If he wants to get to this room for -- the valve 5 piping penetration room, he would come in from the other 6 elevation and go down the stairs and get to this room, and 7 you'll also see some equipment relocated in that area. 8 DR. CARROLL: So, I can go down the stairs as 9 opposed to going through the jail cage -- .10 MR. McINTYRE: Yes. 11 DR. CARROLL: -- anyplace in this -- 12 MR. McINTYRE: Sure. Yes. 13 DR. CARROLL: -- elevation. 14 MR. McINTYRE: And then if you look at the 15 135-foot elevation, it's basically the same. The three jail 16 cages'that went to the MSIV rooms are gone There are the 17 stairs. 18 And basically, it's the same arrangement, that he 19 would go out through here and then he could just card back 20 .in without needing to be searched. 21 The'one other thing that we're doing -- we're 22 having to redo the vulnerability analysis and the security 23 plan as part of this, because it's making a significant 24 change. 25 You recall, last time I talked, we had added a b ANN RILEY & ASSOCIATES, LTD. \\~/~ Court Reporters . 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

1 286 1 security officer for other reasons, and we are going to be () 2 stationing that security officer right here. So, this will 3 be -- I believe our intent right now -- we're still working 4 on the analysis -- would be to have this -- not only have 5 CCTV but have it continuously manned with an officer in that 6 area. 7 CHAIRMAN BARTON: So, he would be there to help 8 people -- l 9 MR. McINTYRE: Right. 1 10 CHAIRMAN BARTON: -- do the ingress and egress -- 11 MR. McINTYRE: Yes. 12 CHAIRMAN BARTON: -- if they had to go out for 13 material or supplies or whatever. 14 Has the staff seen this? ) 15 MR. McINTYRE: They saw it about an hour ago. 16 CHAIRMAN BARTON: Okay. 17 MR. McINTYRE: So, I don't think they'll have any 18 -- well, I'd like the guy to stand -- Ron to stand up and l 19 say, boy, that's a tremendous design. He hasn't seen it and 20 certainly hasn't seen the vulnerability analysis, because we l 21 don't have it done. 22 CHAIRMAN BARTON: Well, in our letter, we asked 23 the staff to go look at the previous design from safety and 24 operational aspects, and so, I'd be interested to see what 25 the staff thinks of this, l [~' ANN RILEY & ASSOCIATES, LTD. \\ Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034 l

i I 287 1 You know, from this brief description you've () 2 given, this looks like a major improvement from what we've 3 seen before. I don't know if it solves all problems. We 4 need the staff to still look at this modified design, but it 5-sure does look like an improvement. 6 DR. SEALE: Will this involve any changes in the 7 expected staffing level-for security? 8 MR. McINTYRE: No. 9 DR. SEALE: You can always add, but you can never i 10 take away. 11 CHAIRMAN BARTON: Just like taxes. 12 MR. McINTYRE: You can't go below a minimum 13 staffing. 14 DR. CARROLL: Now, I think there's a lesson to be 15 learned here, both on the staff's part and on Westinghouse's 16 part. 17 When you get into a highly specialized area like 18 security, you've got to be very careful, because your 19 experts tend to want to have the latest and greatest in 20 their opinion, and they don't really have a lot of regard 21 for what else is implied by their design. 22 MR. McINTYRE: Interestingly enough, the designer 23 who originally had this design was talked out of it by the 24-utility guy. 25 DR. CARROLL: Well, you hired a consultant. O-' ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

288 1 MR. McINTYRE: No, he was a utility security guy. ( 2 He was the one who talked him out of it. 3 DR. SEALE: You just said the magic word. 4 MR. McINTYRE: Yes. 5' DR. SEALE: The security guy from the utility. 6 MR. McINTYRE: Yes. But he is the guy who also 7 has to deal with it in a real-life situation. l 8 DR. SEALE: Maybe he won. 9 MR. McINTYRE: If you look at the old drawings and 10 the new drawings, it looks like -- this equipment was 11 originally here and there was some other equipment here that 12 looks like it may have disappeared. 13 CHAIRMAN BARTON: You had to relocate some 14 equipment? 15 MR. McINTYRE: Yes. What we did is we added 16 another -- it's actually -- the equipment that was here is 17 actually Jitting a little bit off the top here, and we added 18 a partial elevation -- I think it was some tanks or some 19 condensers or some sort of equipment that was here. 20 CHAIRMAN BARTON: Okay. l 21 MR. McINTYRE: These guys were here. They moved 22 over here. The stuff that was here is up. L 23 CHAIRMAN BARTON: He's up a half-a-floor or 24 something. 25 MR. McINTYRE: These are really a low piece of i - FY ANN RILEY & ASSOCIATES, LTD. k/ Court Reporters s 1025 Connecticut' Avenue, NW, Suite 1014 Washington,-D.C. 20036 (202) 842-0034

289 1 equipment. They're not very tall. So, we put like a () 2 platform to put it up there. 3 CHAIRMAN BARTON: All right. 4 MR. McINTYRE: So, this is the proposed change to 5 security. We're in the process of revising the report, and 6 we'll get it in to the NRC, hopefully, in the next couple of 7 weeks-8 CHAIRMAN BARTON: Looks like an improvement. 9 Thank you. 10 Any questions? 11 (No response.] 12 CHAIRMAN BARTON: Well, we're a little ahead of 13 schedule, but we'll break now until 10:15. 14 [ Recess.) 15 CHAIRMAN BARTON: Back in session. 16 I'm sorry, Brian. Next item on the agenda is open 17 items issues. 18 MR. McINTYRE: Okay. 19 I gave Noel -- going to the list, there's one four i 20 down, SRM on 97-044 staff work to understand marginally 1 21 adequate, and I think Tom's comment yesterday -- I think 22 this was Tom's comment is we were going to talk about i 23 that this morning, when Terry did his presentation that had 24 to do with containment spray, that our design was marginally 25 adequate, their terms. Maybe it was your terms, or it was M(s/ ' ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 I (202) 842-0034 I L l h.

290 1 somebody's terms. 2 CHAIRMAN BARTON: It was Tom Kress' concern. 3 DR. SEALE: Well, I think the reason was that, in l 4 the initial discussion of the capabilities of the spray-5 system,.there was some concern as s whether or not it was 6 enough to deliver any significant flow -- 7 MR. McINTYRE: Okay. 8 DR. SEALE: -- against the internal pressure of 9 the containment.

10 MR. McINTYRE:

Okay. 11~ DR. SEALE: And I guess now you've indicated that 12 it's 3,000 gallons per minute with an internal pressure of l 13 20 psi -- I mean 1,000 gallons a minute with an internal 14 pressure of 20 psi. So, I assume that's an adequate 15 fire-fighting flow. 16 DR. CARROLL: Fire-fighting? 17 DR. SEALE: I mean spraying flow. 18 DR. FONTANA: There's a little bit of a gotcha 1 19 there, because in a design basis accident, the passive l 20 system is supposed to hold containment pressure to 45 psi or l 21 less. 22 MR. McINTYRE: Right. 23 DR. FONTANA: Okay. j 24 MR. McINTYRE: Okay. l l .25 DR. FONTANA: Now say you're near there and then l l - O - ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

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291 1 you get into some kind of a glitch for some reason. Now you [) 2 want to use the spray system that's designed for 20. Can't v 3 us' it. 4 DR. CARROLL: The whole notion is that you'd never 5 use the spray system for a design basis accident. 6 CHAIRMAN BARTON: This is really a severe 7 accident. 8 DR. FONTANA: I understand, exactly. I'm saying 9 you're in a design basis accident and now, f or sc.ne reason, 10 something's not working right and you want to use the spray 11 system. 12 CHAIRMAN BARTON: Not designed to do that, Mario. 13 Not intended to do that. 14 DR. FONTANA: But see, you're not going to be at (O) 15 45 psi. You're going to be -- 16 MR. McINTYRE: -- something less. 17 DR. FONTANA: -- something less. If you're at 20, l 18 you're okay. 19 MR. SCHULZ: What we've done is we've tried to 20 mechanistically look at, if you get into core cooling 21 problems, you've got a lot of energy now going into melting 22 the core. It's not going into the containment. The 23 containment brings the pressure down substantially during 24 that damage phase. 25 So, even if the pressure was up at 45 when you had O ANN RILEY & ASSOCIATES, LTD. \\- Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

292 1 your loss of core cooling failure, whatever it was, you ( 2 don't instantly need spray. You don't want spray at that 3 point. You want the spray when the activity comes out. The 4 activity won't come out until after you've damaged the core. 5 That takes time. During that time, that's energy 6 going into the core, not into the containment, and the 7 pressure comes down. So, there's a mechanistic connection 8 between why you would want the spray -- i.e., the core is 9 damaged -- and the pressure coming down. 10 DR. FONTANA: See, once you've got the spray going 1 11 in there, then that will take some containment pressure 12 down. Once you can get it going, you know, you'll be all 13 right. 14 MR. SCHULZ: And what we're saying is that.the () 15 passive containment cooling system will bring the pressure 16 down very nicely to this 20-pound gauge in a severe accident 17 sequence. 18 DR. SEALE: The other question is the 20 -- the 19 three-hour duration of the flow -- or five hours, whichever 20 it turns out to be -- does cover the time span in which you 21 do get delayed gas release, fission product gas release. 22 MR. SCHULZ: That's my understanding, is that's 23 really where the three hours came from. 24 DR. SEALE: Yes. 25 Does that sound right to you, Dana? ('Il-ANN RILEY & ASSOCIATES, LTD. 's / Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

I 293 1 DR. POWERS: You'd have to say it again, Bob. () 2 DR. SEALE: The idea that there is a three-hour 3 duration for the spray system following the 1,200-degree 4 core temperature thermo-couple onset of spray covers the 5 time during which you'd expect to get fission gases 6 released. 7 DR. POWERS: It's really when you have the most 8 intense particle release that the spray's going after, and 9 from everything we have seen, with the new source terms and l 10 things like that, which are fairly strongly based on 11 physical evidence from experiments, the most intense 12 releases are occurring in that -- over a two-or-three-hour 13 period, and then you get a pretty dramatic e-folding on the 14 concentrations, and then, if your containment remains 15 intact, all you're worried about is the leakage problem, and 16 clipping the tops on the concentration does a lot for you. 17 I mean it doesn't take much, and sprays are 18 awfully effective. I mean there are a lot of questions, and 19 some of the chemical engineers phrased questions about -- 20 you've got a lot of droplets coming down, well something's 21 got to cp> up, and if that going up is not uniform, you 22 create some bypass flow, and they worry about that a lot in 23 the chemical processing industry, but it's not so important 24 in the containment, because it's a sealed up thing. 25. So, suppose you do have the spray all pushed to O' ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 .(202) 842-0034

294 1 one side and stuff coming up. Well, that stuff that comes 2 up t a has to come back down again. 3-So, it gets. multiple passes through this thing, 4 and so, some of those subtleties that the chemical 5 engineering community worries about, that, for instance, ~6. this analysis did not, they're interesting, but they're not 7 terribly germane. 8 DR. SEALE: You get more than one shot at it. 9 DR. POWERS: You get multiple shots at the came 10 gas -- 11 DR. SEALE: Yes. 12 DR. POWERS: -- and maybe you. don't know the 13 timing exactly, but you're worrying about big blocks of 14 time, and what happens in any given one minute is pretty () 15 inconsequential. 16 What you're worried about is what happens over 20 17 minutes, 30 minutes, and hour and whatnot, because it's the 18 leakage-type source term that you're worried about here. If 19 you got containment rupture, that's a bad thing. You didn't 20 want to do that anyway. 21 DR. SEALE: Well, I think those were the kind of 22 questions that Tom had in mind when he was questioning the 23 efficacy of the spray system, its capacity to handle those '24 kind of issues. 25-DR. POWERS: Yes. I think, to be quite honest, I i ( ANN RILEY &' ASSOCIATES, LTD. I Court Reporters .1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

295 1 believe Dr. Kress was interrogating to find the depth of () 2 knowledge rather than any doubts about the efficacy of l 3 sprays. 4 MR. McINTYRE: Did we pass? 's CHAIRMAN BARTON: Sounds like you must have. 1 C MR. McINTYRE: Okay. l 7 DR. FONTANA: I have another question here. 8 Now, the PRA was written prior to the 9 consideration of sprays? In other words, potential spray 10 use is not in the PRA? 11 MR. McINTYRE: It's not in the PRA. 12 DR. FONTANA: Okay. 13 Now, the next question is, does the PRA go along 14 with the certification for -- when a utility buys this, are O(_/ 15 they going to be probably required to update the PRA? 16 MR. McINTYRE: The part that goes along with the 17 certification are the insights, which is basically a summary 18 of here are design features that were credited in the PRA 19 that we want to make sure they don't get lost when they 20 update the plant, and whether or not it goes along with 21 design -- you know, what they have to do at design 22 certification time, what we're saying is that they need to 23 make sure that the plant is consistent with the PRA. 24 DR.. FONTANA: Well, the plant's going to be a 25 little different if the PRA's got a spray system in it. l l l () ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

296 1 It's not safety-related. 2 MR. McINTYRE: Well, that won't affect core -- 3 .that would only affect 4 DR. FONTANA: Oh, no. 5 MR. McINTYRE: -- the level three. 6 DR. FONTANA: Yes. 7 MR. QUAY: This is Ted Quay of the staff. 8 To answer part of your question, the staff has 9 before it in the rule-making activity plan a rule that would 10 ask for a living PRA. 11 MR. McINTYRE: I think we can mark that one 12 closed. 13 CHAIRMAN BARTON: Does that staff have any further 14 comment or question on the spray issue? ) 15 MR. KENYON: This is Tom Kenyon with the staff. 16 No, we found it to be acceptable. 17 DR. CARROLL: Marginally. 18 MR. KENYON: Those were your terms. 19 DR. CARROLL: Oh, okay. 20 Well, this living PRA concept would not really be 21 back-fittable to the evolutionary plants or to AP600, would 22 it? 23 MR. QUAY: What it would do is it would tell the .24 COL applicant that they have to maintain the PRA. 25 So, it would be -- in other words, it wouldn't be l~ - '(~/). ANN RILEY & ASSOCIATES, LTD. Court Reporters . 1025 Connecticut Avenue, NW, Suite 1014 Washington, D C. 20036 (202).842-0034

297 1 backfit to the design certification, but as these plants are () 2 going through the licensing process, if any changes are 3 made, that PRA would have to be updated. But that's in the 4 rule-making activity plan. 5 DR. SEALE: Is that for Part 52 plants or all 6 plants? 7 MR. QUAY: That's Part 52 plants. 8 DR. SEALE: Okay. 9 DR. CARROLL: Is that really consistent with the 10 notion of one-stop licensing? 11 MR. QUAY: The certification stands as is. The 12 certification would not change. l 13 MR. McINTYRE: It's not inconsistent. It's more 14 in line with risk-informed, performance-based regulation. () 15 The next item was the -- Westinghouse agreed to 16 discuss the suitability of results of reactivity code, and 17 yesterday, Dr. Powers said tell me what data facts you used, 18 and the next question is why. 19 Noel has to hand out from the SSAR the page 20 15.4-36, and it is subsection -- I love this -- l l 21 15.4.8.2.1.4, which is why we thought it would be easier to 22 hand it out, and I even underlined the answer, so we don't l 23 have to look, and it says, just reading it, "To allow for 24 future cycles, pessimistic values of beta effective of.55 25 percent at the beginning of cycle and.44 percent at end of i \\ ANN RILEY & ASSOCIATES, LTD. N_ Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 l (202) 842-0034

F L 298 1 cycle are used in the analysis," and I'll speak for Dr. () 2 Powers -- I'm sure he won't be bashful here. 3 He said yes, that does, indeed, answer the 4 question, so -- and it explains the why we used it. 5 His one comment he did have was that he thought 6 that perhaps those values were high when we start looking at 7 high burn-up fuels, but that really probably isn't an AP600-8 issue as much as that it's going to be an extended burn-up 9 fuel issue. 10 CHAIRMAN BARTON: Okay. 11 MR. McINTYRE: I'll ask him if he considers it 12 closed. 13 CHAIRMAN BARTON: Dana? 14 DR. POWERS: Yes. I hate to say this, but I think ' () 15 I agree with Brian on this one. 16 DR. SEALE: Spooky. 17 DR. POWERS: There must be something wrong with my 18 thinking today, but'I guess I -- they strike me as 19 conservative for the BOL and optimistic for the long-term 20 burn-ups, but I agree with him, things are sufficiently 21 unresolved enough in that are for the high burn-up fuels, 22 and it's sufficiently -- and whatever happens, we know that i 23 the fuel that's going to be used for extended burn-up in an 24 AP600 reactor is going to be different from any of the fuels 25 that we have now, and so, it would be pointless for ANN RILEY & ASSOCIATES, LTD. + Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

299 1 Westinghouse to go to great heroic lengths to address those () 2 . fuels, and they're going to have to be addressed as part of 3 the loading process anyway, and so, I guess I -- I.also know 4 that the analyses that are-done in the design basis analysis 5 don't give them credit for energy losses into the clad 6 anyway, regardless of the pulse: width. 7 So, I think it's a closed issue here but one to be 8 aware of when we go to loading high burn-up fuel. But I'm 9 sure that that will come of its natural course. 10 CHAIRMAN BARTON: All right. 11 MR. McINTYRE: The next open one is the locked 12 rotor peak clad temperature, and I mentioned that we're 13 working on that one, and we'll submit that in a written 3 14 form, and on the second page, the security design -- -15 CHAIRMAN BARTON: Did we close out' Carroll's item 16 on the adverse interactions? 17 DR. CARROLL: As far as I'm concerned. 18 CHAIRMAN BARTON: You missed one here, Brian. 19 MR. McINTYRE: Well, I already had it closed out. 20 CHAIRMAN BARTON: Oh, you already did.

Okay, 21 DR. CARROLL:

Simply because you got up there and 22 talked,'you're going to close it out? 23 CHAIRMAN BARTON: Jay,.are you happy? 24 DR. CARROLL: Yes. 25 CHAIRMAN BARTON: Okay. ) I O ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 j (202) 842-0034 L_

l 300 1 DR. CARROLL: I thought they did a very () 2 comprehensive job on that. I'm impressed. 3 CHAIRMAN BARTON: I'm sorry. Where are you going 4 next, Brian? 5 MR. McINTYRE: We'll thank Mr. Corelleti for you. 6 I remember, last time, Mr. Corelleti was substituting for _hulz is returning the favor, so Mr. 7 Mr. Schulz. Mr. 8 Corelleti can be in Italy or Spain. 9 The other ones on the next page, security design 10 11 CHAIRMAN BARTON: Yes, marked improvement. 12 Is the staff still looking at this, though? 13 DR. CARROLL: Yes, they're doing a vulnerability Westinghouse is doing a vulnerability analysis. 14 (O _,/ 15 MR. KENYON: We're going to be looking at it 16 probably -- we'll get the vulnerability analysis from 17 Westinghouse about the end of June sometime. So, we can 18 make a comment on it at the July meeting. 19 CHAIRMAN BARTON: Okay. 20 MR. McINTYRE: And we picked up one yesterday from 21 Mr. Carroll that a th1ee-hour fire door is not a smoke door 22 and how do you deal with that, and I think we've answered 23 that before. We'll talk. to Mr. Winters when we get back to 24 Westinghouse and provide an answer on that. 25 And this morning, Dr. Powers wanted to know what G ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

301 i l 1 value we used in the nitric acid calculations. My person i -s} 2 back at Westinghouse is looking for that. 3 The calc note happens to be in our Rockville 4 office. I will scoot out there over my lunch hour and drag l 5 the calc note back and find something in there that says G 6 equals and pass that along to you right after lunch. 7 DR. POWERS: See the penalties you get when I 8 agree with you? 9 MR. McINTYRE: These meetings are like scavenger 10 hunts. 11 So, we're down to a couple of items here. 12 CHAIRMAN BARTON: Okay. l 13 Looks like we ran out of agenda items here. l l 14 Let's talk a little bit about the July meeting, <N(,) 15 what we've still got left to do in July. 16 DR. CARROLL: We're not going to do aerosols? 17 CHAIRMAN BARTON: Where do you see aerosols? 18 DR. CARROLL: Items five and six. 19 CHAIRMAN BARTON: That's getting resolved in l 1 20 Germany. So, we'll probably hear when the troops return I 21 from Germany. 22 DR. CARROLL: You're not going to trust Kress' 23 judgement, are you? 24 CHAIRMAN BARTON: Well, I don't know, at this 25 time, what else we've got to go by. Westinghouse's people l l / ANN RILEY & ASSOCIATES, LTD. kl Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 l Washington, D.C. 20036 l (202) 842-0034 1 i

302 1 are over there, I guess, Kress is over there. () 2 MR. McINTYRE: The staff guy is over there. 3 CHAIRMAN BARTON: Staff is over there. The only 4 person that knows anything about aerosols here is Dana, and 5 he'll be talking to himself, I guess, if we talked about the 6 aerosol issue. l 7 DR. POWERS: I have to recuse myself completely 8 from that. 9 CHAIRMAN BARTON: I think aerosols is a dead issue 10 for today's meetit0 l l '11 DR. SEALE: If he does talk, it's just a mumble. 12 DR. POWERS: I will tell everybody about some 13 exciting news that we are getting out of the -- apparently 14 coming from some of the PHEBUS tests, giving us some () 15 information on shape factors that may be pertinent to 16 aerosol behavior in the AP600 containment. 17 The shape factors are running between two and 18 three from the PHEBUS experiments. That's exciting to me, 19 simply because those are numbers that the staff used in ) 20 their analysis. I have no idea where they got those 21 numbers. 22 DR. CARROLL: Good guess. 23 DR. POWERS: And it's a brilliant model and 24 deductive science that someone somewhere applied to the 25 staff's analysis. 4 -l 1 O ANN RILEY & ASSOCIATES, LTD. Court Reporters 102b Connecticut Avenue, NW, Suite 1014 2 84 $ b34

303 1 DR. FONTANA: Shape factor goes up. Is that () 2 better or worse? Shape factor goes from assumed -- 3 something's assumed spherical to something else. Is that 4 correct? 5 DR. POWERS: Well, that's one view on shape 6 factor. Shape factor is a little more complicated than 7 that. 8 The simplest way to understand shape -- shape 9 factors are a way to deal with the fact that the aerosol 10 physics models are all based on the behavior of spheres, and l 11 aerosol particles aren't spheres, and the simple use of 12 shape factors and where they originally arose was in 13 describing gravitational settling, and bigger shape facters

1. 4 mean sloser settling, so you have higher concentrations in

() 15 the atmosphere and lower concentrations on the floor. 16 So, in depends on where you're worried. 17 If you're worried about dose effects on water 18 solutions and things like that, then big shape factors slow 19 that process down. 20 If you're worried about concentrations in 21 atmospheres and gravitational settling is four predominant 22 concern, then big shape factors mean you have higher 23 concentrations for longer periods of time in your *eactor 24 containment. i 25 Shape factors have very small effect in sprays. [ ') ANN RILEY & ASSOCIATES, LTD. \\s Court ReporterG 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

304l 1 They will -- collision shape factors will enhance removal () 2 due to interception. Other than that, they're~-- sprays are 3 like hitting it with a sledgehammer, and it kind of ignores-4 subtleties. 5 AP600 is not -- is unusual. It has a huge 6 containment, and you'd ordinarily say gravitational cettling 7 is the dominant removal mechanism, but it's a cold ( 8 containment, and if, indeed, the thermal hydraulics in the 9 containment are correctly portrayed, then the dominant 10 removal mechanism is a diffusio-phoretic force on the 11 particles, and diffusio-phoresis and shape factors are 12 things that just don't mesh well. They are two concepts 13 that just have never interacted especially well. 14 If you take a simplistic view and say shape () 15 factors are shape factors are shape factors, then shape 16 factors tend to slow down the diffusio-phoretic removal. i l 17 DR. FONTANA: Steam sweeping them toward the wall. 18 DR. POWERS: That's right. 19 DR. FONTANA: A higher shape factor tends to slow 20 that down? 21 DR. POWERS: Yes. Because you've got steam coming 22 in, that means you have to have a gas coming off to keep l l 23 pressure balanced, and so gas is pushing particles out, it's l 24. got more to push on. It becomes a complicated analysis. 25-But what the staff showed in their analysis, in ANN RILEY & ASSOCIATES, LTD. A Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 i Washington, D.C. 20036 (202) 842-0034 i

305 1 comparison to Westinghouse's analysis, even though they used () 2 different assumptions on the shape factors and things like 3 that, they got about the same amount of removal, and so, it 4 was about the same result. 5 it depends directly on the thermal hydraulics in i 6 the containment, but if everybody agrees on that, then the 7 aerosol physics, everybody kind of agrees. 8 Is that a correct characterization? 9 MR. McINTYRE: I believe that's correct, or fair. 10 CHAIRMAN BARTON: We do have a meeting scheduled l 11 in July, a subcommittee, for the 6th and 7th, and some 12 discussion with Noel and the staff -- it doesn't look like 13 we've got two days worth of issues still on the plate here. 14 It looks more like maybe one day of subcommittee work prior 15 to full committee on July 8th, I believe, is the full 16 committee. So, it looks now like we will be maybe having a 17 subcommittee meeting on the 7th, instead of 6th and 7th, and 18 then the full committee will start on the 8th. 19 We've got rome thermal hydraulic issues, some open 20 questions. 21 Noel, what else is there? 22 MR. DUDLEY: That's it, unless members have any 23 other issues that they need to -- 24 CHAIRMAN BARTON: -- to bring up at that time, i 25 MR. DUDLEY: -- bring up or get answers for. So, l( ) ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 1 (202) 842-0034

l 306 1 this is an opportunity to identify any other questions you () 2 have on the AP600 design so that the staff and Westinghouse 3 can respond, prepare to respond to those in the July 4 meeting. 5 CHAIRMAN BARTON: Now, for the full committee in 6 July, Brian, I think, based on members that are absent, 7 probably an overview of the ITAAC, adverse system 8 interaction, and I don't c, ink we need four hours of PRA 9 level one, but I think enough of the level one to let the 10 members that missed yesterday's presentation get a sense 11 for, you know, how thorough the level one PRA was done. I 12 think there was a real good job yesterday, but I don't think 13 we need that much time on it. You don't have that much time 14 on July 8th at the full committee meeting. k 15 What are we allowing them on July 8th? A couple 16 of hours? i 17 DR. SEALE: Yes. l 18 CHAIRMAN BARTON: So, you've got ITAAC, adverse 19 system, PRA, plus whatever cats and dogs come up between now 20 and then -- l 21 MR. McINTYRE: Okay. l 22 CHAIRMAN BARTON: -- for the July 8th meeting. l 23 MR. McINTYRE: It would be useful for the 24 subcommittee meeting on the 7th if we could get those as 25 soon as -- anything that you want to hear about, because we O' ANN RILEY & ASSOCIATES, LTD. Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

307 1 need to know what -- you're getting to the end when you get () / 2 to cats and dogs. We have to bring an army, and while Mr. 3 Schulz is yeoman, some of these are not necessarily his 4 area. 5 DR. CARROLL: He fakes it pretty good. 6 MR. McINTYRE: Yes, he does. 7 So, rather than -- we can't have any unanswered 8 questions at the end of that. 9 So, anything that comes up, we may bring the army 10 anyway. I don t know, we'll see, but if you guys have any o 11 questions, let us know. 12 CHAIRMAN BARTON: All right. 13 DR. FONTANA: So, it's definite now? We've 14 changed travel and have only a meeting on the 7th. f(, 15 CHAIRMAN BARTON: I don't see a need for a two-day 16 subcommittee. We had this laid out way in advance, the 17 subcommittee meeting, and it just looks like there's not 18 that much left out there. We can't support a two-day 19 subcommittee. 20 I think, you know, if we got one day to wrap up 21 open issues, that would probably be plenty of time we would 22 need for subcommittee. 23 CHAIRMAN BARTON: Has the thermal hydraulic 24 subcommittee finished their -- 25 I think they've had all their meetings. They've t ANN RILEY & ASSOCIATES, LTD. \\- Court Reporters 1025 Connecticut Avenue, NW, Suite 1D14 Washington, D.C. 20036 (202) 842-0034

308 1 ~ got some issues and questions, I believe. [\\ 2 MR. McINTYRE: I think I can speak to that. d 3 MR. DUDLEY: My understanding from talking to Paul 4 is that he will need about two to three hours during the 5 July meeting, the July 7th subcommittee meeting,.to clean up 6 his items. 7 CHAIRMAN BARTON: Okay. So, it looks like maybe a 8 full day on the 7th should do it. 9 Don, you had something? 10 JR. MILLER: I just already scheduled a meeting 11 the afternoon of the 7th, but it doesn't sound like I'm 12 going to be needed anyway. 13 CHAIRMAN BARTON: At this point, do we need the 14 recorder anymore? () 15 DR. CARROLL: I guess I have one thing for the 16 staff. 17 You're going to review the vulnerability analysis 18 for security when submitted by Westinghouse. Are you also 19 going to show the design to some of your more operationally 20 oriented people to see if they can find any glitches in the 21 new design? 22 MR. McINTYRE: I don't know that the vulnerability 23 analysis would help the operational people much, because 24 what that is is, given a threat, how quickly we can respond 25 to it. [/\\ ANN RILEY & ASSOCIATES, LTD. 1 \\s-Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034 i

309 1 DR CARROLL: Yes. Well, I'm just saying, in () 2 conjunction with that, are they going to -- 3 MR. KENYON: I understand your question, and the 4 focus of the staff is going to be, now that Westinghouse has 5 proposed a fix or design modifications to address the 6 particular issue you've raised -- it's not our intent to go 7 back and take a look at the rest of the design in terms of, 8 you know, operability ease or maintenance ease. 9 It goes back to what we were talking about at the l 10 last -- or one of the former subcommittee meetings. If they 11 meet the regulations, if an inconvenience because of 12 maintenance, it's not a problem with the staff. 13 DR. CARROLL: To me, it's potentially a real 14 safety issue, Tom. If the operators are going to be delayed 15 in getting to equipment -- 16 MR. KENYON: I don't have the security man here, 17 but he'll tell you, when there is a problem of operability 18 and there is a need to get access to this equipment, a lot 19 of the security -- it's my understanding that a lot of the 20 security requirements are temporarily put on hold. 21 DR. CARROLL: That's correct. You can throw a 22 switch and open the doors. 23 MR. KENYON: So, we're looking at it from the 24 perspective of addressing the particular concern. 25 We understand and agree with you that it was a l) ANN RILEY & ASSOCIATES, LTD. V Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034

310 1 good idea to make the modification, but other than that, we () 2 feel that the other security measures that are in place and 3 the capability to remove security requirements in case of 4-emergency meet the regulations and are adequate. 5 DR. CARROLL: Okay. 6 CHAIRMAN BARTON: Any other discussion questions 7 at this time with Westinghouse or the staff? If not, I 8 don't think we need the recorder anymore. 9 [Whereupon, at 10:47 a.m., the meeting was 10 concluded.] 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 n' ( ANN RILEY & ASSOCIATES, LTD. '\\ I Court Reporters 1025 Connecticut Avenue, NW, Suite 1014 Washington, D.C. 20036 (202) 842-0034 l

REPORTER'S CERTIFICATE This is to certify that the attached proceedings before the United States Nuclear Regulatory Commission in the matter of: NAME OF PROCEEDING: SUBCOMMITTEE ON ADVANCED REACTOR DESIGNS f DOCKET NUMBER: 1 PLACE OF PROCEEDING: Rockville, MD 1 l were held as herein appears, and that this is the original transcript thereof for the file of the United States Nuclear Regulatory Commission taken by me and thereafter reduced to typewriting by me or under the direction of the court reporting company, and that the transcript is a true and accurate record of the foregoing proceedings. b . AM (( U 0 Jon Hundley l l Official Reporter Ann Riley & Associates, Ltd. 1 O}}

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