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Transcript of 931008 402nd ACRS Meeting in Bethesda,Md.Pp 262-377
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Issue date:	10/08/1993
From:	; Advisory Committee on Reactor Safeguards
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	ACRS-T-1981, NUDOCS 9310130294
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%w ACRsT-Its/ i ^~ i 10 FFICIAL TRANSCRIPT OF PROCEEDINGS ' t t -i m..i Agency: Nuclear Regulatory Commission. Advisory Committee on Reactor Safeguards

Title:

402nd ACRs Meeting I - i Docket No. B<TND .,:a r; w ::q r.y %. ; j'2 lj W{^ [ y,.. O w ~ fp, ~ t. 00[}c}99] Af-789/QU;Mj2g(3g .g ~ i LOCATION: Bethesda, Maryland ' i J - i DATE. Friday, October 8, 1993 PAGES: 262 - 377 flhhh ~f[f.29 P;unR9V l c-e n 30 Not Remove from ACRS 07 ice 1 .O 130098 ANN RILEY.& ASSOCIATES, LTD. 1612 K St.,N.W. Suite 300 Washington, D.C. 20006 j 9310130294 93i008 (202) 293-3950 PCR ACRS l T-1981 PDR 1' - J

_~. PUBLIC NOTICE BY THE O UNITED STATES NUCLEAR REGULATORY COMMISSION d ADVISORY COMMITTEE ON REACTOR SAFEGUARDS i .I DATE: October 8, 1993 I 'l O The contents of this transcript of the proceedings of the United States Nuclear Regulatory Commission's Advisory Committee on Reactor Safeguards, (date) October 8, 1993 , as Reported herein, are a. record of the discussions recorded at-the meeting held on the above date. l This transcript'has not been reviewed, corrected I or edited, and it-may contain inaccuracies. i 'j 4 t (O i ANN RILEY & ASSOCIATES, Ltd. i Court Reporters 1812 K. Street, N.W., Suite 300 Washington, D. C. 20006 .l t&IcwA>Mterea

', 1 262. 1 UNITED STATES OF AMERICA 2 NUCLEAR REGULATORY COMMISSION 3 s 4 ADVISORY COMMITTEE ON REACTOR SAFEGUARDS 5 6 7 402ND ACRS MEETING-4 I 8 s i 9 10 Nuclear Regulatory Commission 11 Conference-Room P-110 i 12 Phillips Building I. 13 7920 Norfolk Avenue 14 Bethesda, Maryland o 15 q b I 16 Friday, Oct)ber 8, 1993-17 I h 18 The above-entitled proceedings commenced at 8:32 19 a.m., pursuant to notice, J. Ernest Wilkins, Jr., Committee i l 20 Chairman, presiding. 22 .i 22 ACRS MEMBERS PRESENT: -l l 4-23 l 1 24 J. WILKINS, Chairman 25 J. CARROLL, Vice Chairman of the ACRS 4 I 4 i ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K-Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

ij i 263 l N 1 ACRS MEMBERS PRESENT (Continued) : j 2 3 T. KRESS i 4 C. MICHELSON i l 5 W. LINDLBAD { i 6 P. DAVIS -I 7 R. SEALE -l 8 W. SHACK j 9 I. CATTON 10 C. WYLIE i 11 t 12 l 13 14 15 ) 16 i 17 18 i 1 19 20 r [ I 21 22 ? 23 i i 24 l 25 i t ANN R.ILEY & ASSOCIATES, LTD. Court Reporters l 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 (202) 293-3950 I

-~ .= l 264 1 1 PROCEEDINGS 2 [8:32 a.m.) 3 MR. WILKINS: The meeting will now come to order. l 4 This is the second day of the 402nd meeting of the 5 Advisory Committee on Reactor Safeguards. During today's I 6 meeting, the Committce will discuss and/or hear reports on i 7 the following: l 8 One, steam generator tube rupture event at Palo i 9 Verde, Unit 2. Two, proposal final amendments to 10 CFR, l 1 1 10 Part 55. Three, report of the Planning and Procedures l i I 11 Subcommittee. Four, preparation of ACRS reports.

Five, j

12 ACRS Subcommittee activities. l ? f 13 Portions of today's meeting may be closed to 1 14 discuss organizational and personnel matters that relate i 15 solely to the internal personnel rules and practices of this l 16 Advisory Committee, matters the release of which would s 17 represent a clearly unwarranted invasion of personal 18 privacy, and to discuss proprietary information related to 19 Westinghouse AP600 test programs. t i 20 This meeting is being conducted in accordance with j 21 the provisions of the Federal Advisory Committee Act. Mr. 22 Doug Coe is the designated Federal official for the initial j t i 23 portion of the meeting. l i 24 We have received no written statements or requests I { 25 for time to make oral statements from members of the public l l t l i ANN RILEY & ASSOCIATES, LTD. Court Reporters l 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 { (202) 293-3950

1 i-265. l 1 regarding today's sessions. A transcript of portions of the 2 meeting is being kept. It is requested that each speaker 3 use one of the microphones, identify himself or herself, and i 4 speak with sufficient clarity and volume so that he or she i 5 can be readily heard. 6 I don't have any observations of general interest f 7 to make. Are there any from any of the members of the j 8 Committee? t ^ 9 [No response.] 10 MR. WILKINS: If not, we will then proceed with i F 11 the first agenda item, which is a discussion of the Palo 12 Verde Unit 2 rupture event. i 13 Mr. Carroll, you are the Subcommittee Chairman. 1 14 MR. CARROLL: Okay. This event, which occurred l L 15 back in March, is very interesting from a nunter of points i 16 of view. I am particularly interested in hearing about how 17 the operators responded to it because I think there are some 18 real lessons to be learned there. I think we are also very l l 19 intcrested in the failure mechanism of the steam generator l 20 tubes. 1 21 So, with that I will turn it over to Mr. Chaffee l e 22 to tell us about those things. t 23 MR. CHAFFEE: Thank you. I am Al Chaffee. I am l l 24 Chief of the Events Systems Branch. We brought several l 25 folks here today to make presentations and be prepared to { i s 3 ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 (202) 293-3950 1 l f

266 l 1 1 try to. answer your questions. () 2 Jim Wiggins, who is the Division Director for the ] 3 Div.tsion of Engineering is here. He is our senior staff 'I l 4 member. We also have Bob Jones who is a Reactor Systems. 5 Branch Chief present and the Project Manager, as well as t 6 many other folks as well. l 1 7 The presentation is going to be made by three-l 3 I i 8 different folks today. The first one is Dennis Kirsch. [ 9 Dennis was the Augmented Inspection Team Leader. He will 10 make the first presentation, and spend about a half a hour j 11 taking us through the sequence of events, and talking about 12 what the team found, and the various problems that they I t 13 found. -f i 14 At that point,' Jim Reese, who is the Branch Chief 15 in Region 5 for the Facilities Radiological Protection i 16 Branch, will talk about another aspect of activities prior f i 17 to the event regarding the problems the licensee had in 18 detecting the leak. We are also in the process in putting 'l 19 an information notice out on that. i r 20 Then last, Ken Karwoski from the Materials and t 21 Chemical Engineering Branch, will talk about the cause of f k 4 the tube rupture and NRC actions that are taking place in l l 22 2 23 regard to that. Also, Jim Wiggins will probably mention a l 24 few things at the end about what the NRC is doing in the big l 25 picture relative to the variety of steam generator tube [ h 1 5 i ANN RILEY & ASSOCIATES, LTD. l I l Court Reporters l 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 5 (202) 293-3950 1 i I ..., _ _ _. _. ~.. J

i 267-1 problems that have-occurred of late. 2. Hopefully we will get this all done in an hour and 3 a half. When we did the dry run on this, there is a lot of .i 4 information. So hopefully you will see we will be touching ]. 1 5 some of the high points. We will try to go in depth ) + 6 wherever you want to, to the extent we can. 7 d i l 7 So at this point I will turn it over to Dennis i-8 Kirsch. i j 9 MR. CARROLL: What's this Region 5 business? I-10 thought that had disappeared. I l 11 MR. CRAFFEE: Not yet. ] i f 12 MR. CARROLL: Not yet. Okay. i 13 MR. WILKINS: What is the effective date of that? j j 14 I know that is an unfair question, but maybe you know. 15 MR. KIRSCH: October 1, 1994. i 1 i 16 MR. WILKINS: '94. Th

e. you.

4 ) 17 MR. CARROLL: I noticed when I talked to Dennis 18 over across the street he is already cowboy boots. I don't 19 know what that means. f l 20 MR. KIRSCH: This ol' Montana boy doesn't have-far l i 21 to go, to go to Texas. -) l '22 [ Laughter.] [ -l j 23 MR. KIRSCH: Good morning. My name is Dennis i 24 Kirsch. I am with Region 5, soon to be a Field Office of i 25 Region 4. Where my career is going to lead, God only knows.. i a ANN RILEY & ASSOCIATES, LTD. l i Court Reporters j 1612 K Street, N.W., Suite 300 j Washington, D.C. 20006 i-(202) 293-3950 i _, ~,,. -,,. - - _ _

- _. _ - ~. _ i ? 268 f 1 First of all, let's go through a little bit of the .j h 2 sequence of. events. Could you focus that, please, or is 3 that my eyes? Good. 4 On the 14th of March '93, the Palo Verde Unit 2 i ~ 5 had a steam generator tube rupture at 4 :34 in the morning. 6 Based upon an analysis of the initial pressurizer level 7 curves obtained from the T-DAS system, the leak rate was j 8 approximately 240 gpm at the time of rupture. It decreased l t 9 exponentially or quadratically, as one would expect, with j 10 pressure decrease in the primary system. 11 The main steam line r.liation monitors alarmed at f I i 12 that time for Steam Generator Number 2. At 4:47, the' 13 operators figured out that they weren't going to be able to j 14 hold on to that thing so they manually tripped it before it l 15 went out itself. i 16 At 4:48, the safety injection containment I 17 isolation actuation signal automatically initiated. With l 18 that, the main steam line radiation monitor alarm clears and j I 19 the blow down isolates. Why did that happen? You can take 20 away the N-2 from the main steam line radiation monitor and I 21 the blow down isolated due to the containment isolation i j - i 22 actuat1on 31 gnat. 23 At 5:02, the alert was declared. Why did they 24 declare an alert? The alert is declared, according to their-l. 25 EPIPs on a leak greater than 44 gpm. 1 J ANN RILEY & ASSOCIATES, LTD. l Court Reporters 1612 K Street, N.W., Suite 300 i Washington, D.C. 20006 (202) 293-3950 i 5

j; 269 a 1 At 06:03, they commenced cool-down in accordance 3 i 2 with their functional-recovery procedures. You will notice 3 in here from the time of the rupture all the way down to the l 4 point that they isolated the steam generator was j j ] 5 approximately 2 hours and 54 minutes-. l 1 6 That was a long time. That' bothered us. It still' l l 7 bothered us a little bit, but'during the AIT we determined j i ) 8 that the utility at no time was in danger of releasing l 9 activity off-site or to have caused a danger to the public. l ) 10 They were following their procedures, going through all 11 their procedures in a deliberate manner. i 12 At 06:24 they exited the functional recovery .l 13 procedures after they recovered the pressurized level to 14 better than 33 percent. That is the criteria that they can l 15 exit the functional recovery procedure. They reentered the i + 16 diagnostic logic tree at that point. 1 i 17 Shortly thereafter, they diagnosed the steam l i i 18 generator tube rupture and continued down through at 7:28, -l } 19 isolated the generator. At 10:29, they entered Mode 4. 20 Then on the next day they terminated the alert. I 3 21 MR. MICHELSON: Excuse me, you are using that 33 22 percent number on the pressurizer level. There is a i 23 corresponding subcooling requirement on that; isn't there? I 24 MR. KIRSCH: Yes. 25 MR. MICHELSON: Where were they on the subcooling? 1 e i-ANN RILEY & ASSOCIATES, LTD. l Court Reporters j 1E12 K Street, N.W., Suite 300 i Washington,.D.C. 20006 ) (202) 293-3950 l l

.. ~.. _.. _. _ _ _ _ _ _ _ l t 2 270 1 MR. KIRSCH: They were above their subcooled 2 margin. l r 3 MR. MICHELSON: Okay. Do you know by how much? l i 4 MR. KIRSCH: I don't know the exact number, but ( 5 they did have sufficient margin above that number. 1 6 MR. MICHELSON: But they were following their 3 1 7 subcooling cu: /e down as well? 8 MR. KIRSCH: They maintained that pressure during i i 9 that period of time up in the neighborhood of 1,800 pounds, j i 10 So they were well above. j i 11 MR. MICHELSON: Oh, that should be well above it, 12 yes. Okay. They weren't coming down very fast, in other } l 13 words. l i 14 MR. DAVIS: I have a related question. In the l 15 more detailed chronology that we have, the operators .j 3 l l 16 energized the pressurized backup heaters manually. I guess ) 17 that is before they knew they had a tube rupture? I i 18 wouldn't guess that would be a good thing to do. i i 4 j 19 MR KIRSCH: No, they didn't know that they had a 20 tube rupture at that time; that is true. They knew they had 21 a leak. The backup heaters -- they turned them on manually 22 to try to recover pressure. They didn't know how bad the 23 leak was at that point. 24 MR. DAVIS: Okay. One other thing. I noticed a 25 they also isolated the steam generator atmospheric dump ANN RILEY & ASSOCIATES, LTD. l Court Reporters l 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 l (202) 293-3950 ) i 1 A

~, 271 i i 1 valves and switched it over to manual operation. Is that' l 2 part of the procedures? 3 MR. KIRSCH: That is a part of the procedure. i 4 MR. DAVIS: You are violating the protection of 5 the secondary when you do that, it seems to me. Now you are' 6 going to depend on the operator to open those valves if the 7 pressure gets too high? 7 i 8 MR. KIRSCH: That's right. That was a part of 9 their procedure as part of that kind of a trip where they 10 have that sort of thing happening. The part of the guidance l i 11 in their procedure and the way they are trained on the i 12 simulator was to put those dump valves and those atmospheric 13 dumps in manual. j i 14 MR. MICHELSON: That doesn't affect the safeties, { l 15 of course. I 16 MR. DAVIS: The safeties are still there. l 17 MR. BERNIER: My name is Dick Bernier. I am from } l 18 Palo Verde. There is no automatic function on the automatic l 19 dump valves. They are strictly manually operated. 20 MR. DAVIS: There is no automatic function on the t f 21 automatic dump valves? 1 22 MR. BERNIER: On the atmospheric dump valves; I'm j 23 sorry. l l 24 MR. DAVIS: Okay. Thank you. 25 MR. KIRSCH: Thanks, Dick. i 1 l 1 ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 4 -v = ,,, - +,, -...m-c., --,,---im,,,,,,,-,m.,,, ,---,,%,,-.p-y- ,,w,-,,-,ymm,.,%,,,e,3 .--e.- g.-.ne wn 1 -++ g e, p e, y e--y

l 272 1 MR. BERNIER: You're welcome. 'k_ 2 MR. CARROLL: Dennis, for the benefit of some of 3 the members of the Committee who aren't as familiar with 4 steam generator incidents, could you explain what steam 5 generator 2 isolated means? When are you isolated? 6 MR. KIRSCH: That means buttoned up, close the 7 main steam isolation valve, and the feed valve. 8 MR. WILKINS: Which means that no fluid is 9 entering and no fluid is -- 10 MR. KIRSCH: Well, they were feeding on the bypass 11 for some period of time when the main steam isolation valve 12 was open. Once they got the steam generator pressure and 13 the primary pressure equalized, they could button the steam 14 generator up and there would be no more substantial 15 inventory gained in the steam generator. ? 16 Next slide, please. 17 [ Slide.) 18 MR. KIRSCH: The AIT made a number of conclusions 19 and findings in these four primary areas: emergency 20 operating procedures, radiation monitoring system 21 contributors, the emergency plan implementing procedures, 22 and in human factor training deficiencies. 23 First of all, the emergency operating procedures. l 24 AIT found that the utility had a flawed approach in the use 25 of their diagnostic logic tree. They chose to implement the f i ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 e .,a

i l 273 1 statement of the CEN 152 with the question of'CEN 152, "Is 2 there activity in the steam plant?," by asking the question, 3 "Was there an alarm on one of three radiation monitors?," 4 that being, main steam line monitors, the blowdown monitors, 5 or the condenser air rejecter exhaust monitors. 6 The process that they used was that, at the. point 7 in time where they were proceeding through the tree, they 8 asked the question at that point in time, neglecting whether l 9 or not there was a trend previously. At that point in time 10 when they were proceeding through this tree, there was no 11 alarm. After the reactor tripped, the main steam line 12 monitor went away and there were no more alarms, therefore, 13 it did not branch them off to the steam generator tube 14 rupture procedure. 15 They continued through the diagnostic logic. tree 16 until they reached a point where it led them.to a non-17 complicated reactor trip. They knew that that was wrong. 18 They went back to the beginning of the diagnostic logic 19 tree, and proceeded through it again, and arrived at the 20 same point because of that flawed snapshot approach. That i 21 has been corrected. 22 MR. CARROLL: Am I right in saying that they had 23 only shortly before this time implemented new EOP's that had 24 this feature? 25 MR. KIRSCH: Shortly before thic time, they had ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

I 274 1 completed revised or substantially revised their emergency l 2 operating procedures, that is true. 3 MR. CARROLL: But they were well-trained on these 4 new procedures, on the simulator'and so'forth? 5 MR. KIRSCH: Yes, sir. Indeed they were. l 6 MR. WILKINS: And the new procedures have this 7 flawed logic? 8 MR. KIRSCH: Yes. 9 MR. WILKINS: How about the previous ones? You I i 10 didn't go back that far? I 11 MR. KIRSCH: We didn't concern ourselves with the l 12 previous ones. 'i 13 MR. WILKINS: Yes, who cares, right? Fair enough. 14 Does the NRC, as a matter of routine, look at emergency i 1 - @ r i 15 operating procedures when they are substantially revised? l 16 MR. KIRSCH: Yes, sir. We had done up an EOP'on i 17 these procedures previous. { i 18 MR. WILKINS: So NRC missed this also? l i 19 MR. CARROLL: Apparently so. <j i I j 20 MR. KIRSCH: Continuing, their emergency operating 21 procedures do not allow for re-diagnosis of an event after 22 they enter the functional recovery procedures. Once they_ 23 went through into functional recovery procedures, they 24 proceeded through these functional recovery procedures, as I. 25 said, in a very deliberate manner. They knew that plant was j ANN RILEY & ASSOCIATES, LTD. j Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 u

3: 275 safe;_they knew that proceeding through these procedures j 1 1 2 would maintain the. plant in a safe condition. j i. 3 There was no exit in the functional recovery i j 4 procedures to re-branch them back into the diagnostic logic .l f 5 tree or out into the steam generator tube rupture procedure. .l J

i i

6 There, however, was one -- the application of a continuously 1 7 applicable condition in a functional recovery procedure-

)

[ 8 would have allowed a transition to the steam generator tube l 9 rupture procedure. i i 10 During the transition through the functional i =i 11 recovery procedure, when they came to a point which asked: l i j 12 "Was there an alarm on the radiation monitor?," if that I !i t 13 alarm, that indication in the functional recovery procedure, l 14 had been a continuously applicable step as you transition f 15 the functional recovery procedure, within five minutes of i l 16 asking that question an alarm did come in, and it would"have j 17 transitioned them to the steam generator tube rupture t i 18 procedure. But that alarm, that question at that point was l l 19 not a continuously applicable question through that sequence i i 20 of the functional recovery procedures. As a result they did l l 21 not transition. l i l 22 MR. CARROLL: In interviewing the operators, l 23 Dennis, how soon did they really know they had a steam )/ 24 generator tube rupture, but they still had to act like j 25 robots and follow the procedures? l l' l a i ANN RILEY & ASSOCIATES, LTD. Court Reporters l. 1612 K Street, N.W., Suite 300 L Washington, D.C. 20006 (202) 293-3950 t

1 -4.A+ 4 W 1 d.-.am.. .e W. a a l 276 l i 1 MR. KIRSCH: Based on our interviews with the 2 operators, several of them indicated that very early on in ^ t 3 this event they knew -- they believed they had a steam l 4 generator tube rupture procedure. Very early on in the ] 5 event. They were most reluctant to deviate from their j 6 training and their procedure set, and go directly to a steam j 7 generator tube rupture procedure because, to be quite 8 honest, they had been roughed-up rather badly previous for 9 doing precisely that. 10 MR. DAVIS: I have a related question. According j i 11 to the report, they may have been confused a little bit by a i 12 high temperature indication on the pressurizer relief valve ) i 13 tailpipe which existed at the time of the event. i 14 MR. KIRSCH: That really caused them no confusion 15 at all. That was due to a leaking valve and had been in i 16 place for some time. 17 MR. DAVIS: I thought that you weren't supposed if f i 18 that valve -- if that temperature was showing an elevated I 19 indication. You don't know of any restrictions? This is i 20 the same thing that happened to TMI 2. I think they were l 4 21 out of spec with that high temperature on the relief pipe. l 22 MR. MICHELSON: At TMI they were. 23 MR. KIRSCH: This, if I recall, was not that high l 24 a temperature. 25 MR. DAVIS: Okay. It just says here that this ' l idN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

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) l 277 i 1 made the operators. consider'a stuck open-pressurizer relief j 'f J 2 valve. 3 MR. KIRSCH: They thought about it and rejected l 4 it. I I 5 MR. DAVIS: Okay. Thank you. i i 6 MR. MICHELSON: What kind of training did they' l i 7 have on the simulator using this same EOP? I assume it was 8 tested on the simulator. l t 9 MR. KIRSCH: It certainly was. They proceeded { 10 through their emergency operating procedures in the plant l 11 during the event in precisely the same like manner that they j l 12 had been trained on the simulator. ?

f 13 MR..

MICHELSON: Why didn't they pick up then on l b c, l 14 the simulator because the simulator is simulating the real .I t 15 event, and their procedure didn't lead to the right 16 conclusion? i 17 MR. KIRSCH: There is more to the story. Next .I 18 slide please. I 19 MR. CARROLL: There is the answer. 1 [ 20 MR. KIRSCH: Radiation monitoring system l 21 contributors. As it turns out, the utility based their set. l I l 22 point of the alert and alarm points on the main steam line 23 condenser exhaust monitors on not exceeding the regulatory j l I 24 dose limits, I believe, 500 MR at site boundary. J l 25 Information notices 88, 99 and 9143, utility did l t I f l ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 i (202) 293-3950 i i

____-m. t i 'l 278 l 1 look at those. There response to those information notices-l 2 did not result in a complete evaluation of the condenser ~ 3 vacuum' exhaust monitor. set point'. What does that mean? j 4 The condenser vacuum monitor exhaust set point i 5 with the activity that was in the primary system at that 6 time, and with the leakage that occurred 240 gpm, that alarm e 7 would have gone off in approximacely, as calculations later 8 turned out, about 20 minutes. i i 9 Now, in partial answer to your question, Mr. 10 Michelson, the training of the operators in the simulator, ) } 11 led the operators to believe that on a steam generator tube I i 12 rupture you will get either main steam line monitor or that i 13 alarm within two to three minutes, and they will lock in. + 1 14 The design of the facility did not let that happen, l 15 therefore, training in this regard was negative. Next i 16 slide. Any questions there? l 17 [No recponse. ) 18 MR. KIRSCH: Emergency plant operating ) 19 implementing procedures. They emergency plant operating l i j 20 procedures didn't differentiate between a small break LOCA l 4 { 21 and a steam generator tube rupture procedure. The guidance l ? 22 of NUREG-0654 was not implemented. You can't classify a l 23 steam generator tube rupture procedure separately as an 24 alert and treat it separately from a small break LOCA. That ] 25 was the utility's choice. They are evaluating, or at least l b ANN RILEY & ASSOCIATES,. LTD. Court Reporters 4 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 i (202) 293-3950 l 4 r i -.a,- l

l 279 [ 1-some time ago. Maybe Dick Bernier would be able to tell me ll 2 whether they've completed that evaluation, but they were 3 evaluating treating those two events separately. 4 MR. BERNIER: I think the EPIP's have been changed 1 5 already, Dennis, to treat them as separate events. 6 MR. KIRSCH: Thank you. The leak rate in access 7 of the available changing pump capacity would have been 8 classified as a site area emergency. 9 MR. WILKINS: Excuse me. You said., "would have l 10 been," but for what event? 11 MR. KIRSCH: Pardon me. l 12 MR. WILKINS: Your language says, "Would have been 13 classified." 14 MR. KIRSCH: That's right. l l 15 MR. WILKINS: And I am asking: but for what event? a 16 MR. KIRSCH: Okay. But for what. The utility 17 operators entered their emergency plan implementing 1 18 procedures, and they knew at the time they entered the I ( 19 emergency plan implementing procedures that they had a leak l 20 in excess of 44 gpm. They had the charging pumps -- all i i 21 charging pumps were running charging into the plant, the l 22 pressure was down in the neighborhood of around 1800 23 something-in-that-order pounds. 24 They though -- the utility thought that they were 25 in excess of 44 gpm, which would, in accordance with their ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

l I 280 f ~ 1. _ procedure, lead them to an alert. However, if the utility-i 2 operators remembered or recalled that back during the 1 3.. initial phases of the' event, they'had'a' leak rate far in l i 4 excess of the 44 gpm. They knew that because three charging l i 5 pumps came on and since three charging' pumps came on that { 6 put them in the neighborhood of somewhere around 120 gpm, L 7 and that they would have been classified as a site area 8 emergency. 9 MR. CHAFFEE: Let me interject something. So' 10 because apparently the licensee didn't distinguish between a j i 11 steam and a tube rupture, a small break loss of coolant j 12 accident, having a leakage in excess of their charging ~ pump 13 capacities got them into a site area emergency. Whereas, if 14 they had had that distinction, they would not have been in a I 15 situation where they should have declared a site area j 16 emergency because identifying it as a steam or tube rupture, I 17 you could have higher leakages and not get to that level of 18 emergency classification? 19 MR. KIRSCH: Yes. Now, also if you look at^ the. i 20 event, it wasn't classified as required by the emergency 21 plan implementing procedures, but no one on the team or_in l 22 the agency ever believed that this thing was properly a site 23 area emergency throughout. It was at the right level. How l 24 did it turn out to be pretty much at the right level? By a 25 combination of circumstances. ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

m 281' 1 EOF and TSC. Utility has a' goal of activating l 2 them in one hour. They weren't activated within one hour. 3 It was some number -- some few minutes over that hour. 4 However, when they were activated, they were staffed with t 5 adequate numbers of highly-qualified people. i 6 MR. CARROLL: What day of the week'was this? 7 MR. KIRSCH: Pardon me, please. j 8 MR. CARROLL: What day of the week did this happen l 9 on? 1 10 MR. KIRSCH: Oh, hell. Sunday. That's right. I 11 was drug out of bed. ] 12 MR. CARROLL: Okay. I 13 MR. SEALE: At 4:35 in the morning. 14 MR. KIRSCH: That's right. i 15 MR. CARROLL: I understand. But, of course, 16 everybody lives very close to Palo Verde. .j 17 MR. KIRSCH: It took them -- it took everybody a 18 while to come in. l t 19 MR. CARROLL: Tell me about this one-hour goal. t 20 Is that a regulatory requirement? Is that something that is 21 just normally done? 22 MR. KIRSCH: I don't know. Maybe Jim Reese gan t 23 answer that question. I think the goal of tae emergency [ t 24 operating plan goals -- it is a goal. 25 MR. REESE: It is just that: it is' goal. We try t ANN RILEY & ASSOCIATES, LTD. . Court Reporters 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 (202) 293-3950 l ., f

l 282 i 1 to have people staff the facility within an hour, and we try 2 to make the approval of their plan contingent upon that. l 3 But it is a goal, so there is no regulatory requirement on I i 4 that. 5 MR. CARROLL: Okay. But in a situation like Palo 6 Verde where everybody lives an hour away or more, that's a 7 pretty tough goal to meet, isn't it? 8 MR. REESE: An extremely tough goal to meet. 9 MR. LINDBLAD: I'm not sure I understand. Does 10 activated within one hour mean one hour after being called. 11 out, or one hour after the event? i 12 MR. REESE: One hour after declaration of the 13 event. l 14 MR. KIRSCH: Declaration is the key. i 15 MR. DAVIS: According the report, it'was like two i 16 hours before they were activated, 6:42 and 6:50. 17 MR. KIRSCH: Yes. i 18 MR. DAVIS: So it was more than one hour and a few l 19 minutes, I guess. 20 MR. WILKINS: It was two hours. 21 MR. CARROLL: No, after declaration of the event. 22 MR. KIRSCH: After declaration. 23 MR. CARROLL: Not after -- 24 MR. KIRSCH: Declarations. And it shortens that 25 two-hour time up somewhat. ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

.. - -. ~..... t 'l Li 283 1 MR. WILKINS: The al'ert was declared at-5:02, if-I. 2 read this correctly. f 3 MR. CARROLL: Yes. i E 4 MR. KIRSCH: Okay. The assembly and the 5 accountability. They have a requirement in their procedures 6 of doing -- being able to accomplish this within 30 minutes. [ i 7 Due to a combination of circumstances, it took them about.6 8 hours and 44 minutes to do that. f 9 MR. CARROLL: Now, how good was the NRC response j i 10 to this? How quickly did Region V put its emergency l 11 response facility into operation on a Sunday morning? 12 MR. KIRSCH: Let me see here. i 13 MR. CARROLL: How quickly did you. activate the t 14 response facility? 15 MR. KIRSCH: Yes, we did do that. Let me think. 16 I think we activated somewhere, if I recall, right around 17 6:00 o' clock in the morning. I think I got over there j 18 around 6:00 o' clock in the morning. There were a f 19 significant number of people already at the emergency l 20 response facility from the region. 21 MR. DAVIS: They were notified at 5:30, according 22 to the -- 23 MR. KIRSCH: Yes. I \\ 24 MR. DAVIS: Okay. 25 MR. KIRSCH: And I got there somewhere between i t ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 (202) 293-3950

284 1 6:00 -- somewhere between 6:00-6:30. I know Stu Richards 2 gave me a call. 3 MR. CARROLL: How about here in Bethesda? 4 MR. KIRSCH: Good question. I don't know the 5 answer to that, sir. 6 MR. CARROLL: Was it activated? 7 MR. KIRSCH: Oh, yes. Oh, yes. It was with some 8 difficulty, however, because of a real good snow storm 9 during that period of time. 10 MR. CARROLL: Oh, I know that weekend. 11 MR. KIRSCH: The staff back here had to run aroOEd 12 with some four-wheel drive and drag people in. 13 MR. CARROLL: It certainly was. 14 MR. KIRSCH: Okay. 15 Human factors. As I said before, in the 16 simulator, the condenser vacuum and main steam line monitor 17 alarms are programmed in the simulator to come in and remain 18 in alarm within two to three minutes of the event. That is 19 not quite the way things happened in the real world.

Small, 20 unmonitored steam release pathways, such as a unit auxiliary 21 steam relief line were not adequately addressed in simulator 22 exercises or in the classroom.

23 Why are we talking about this? It turned out that 24 March 4th Unit 1 operators realized that because Unit 2 had 25 a small steam generator tube leak that it would not be a \\ ANN RILEY & ASSOCIATES, LTD. Court Reporters I 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

-m t 285 -1 realigood idea to supply the' auxiliary steam header.from f 2 Unit 2 steam, as it.had been previously. Shortly 3 thereafter, in' fact, the very next morning, the supply for l 4 the auxiliary steam header for the site was changed to Unit l 5 3 steam. However, Unit 2 still was the supply for Unit 2 t 6 auxiliary steam. l 7 During the event, the operators had reports which l t 8 later no one could confirm and later turned out to be false, i 9 that an auxiliary steam relief line had lifted at' Unit 2, i 10 meaning that this was an unmonitored pathway. And the j ) i 11 operators' training in the simulator or in the classroom i I i 12 only considered very large sources of unmonitored release i l 13 being such as a steam generator relief or an ADV or 14 something like that. t L 15 Simulator training did not discuss the q l t i 16 possibilities. J 17 MR. CARROLL: What's the resolution of this? a a 18 MR. KIRSCH: They have fixed that. l 19 MR. CARROLL: In what sense? Did they put j I s 20 monitors on it? 1 ] ii 21 MR. KIRSCH: No. It's not monitored, but they -- I f 22 the utility has made the operators and the people aware that-i 23 there are a number of significant pathways which may be ' { 24 smaller than those large ones and what to do about those and 25 how to be aware -- make sure that they are aware of those. l l t fh ANN RILEY & ASSOCIATES, LTD. Court Reporters j 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 b-7...

286 1 It is in the simulator, and it is in the-train in the 2 classroom now. 3 MR. CARROLL: Okay. 4 MR. KIRSCH: The simulator training did not 5 discuss the possibility that high-pressure safety injection 6 flow may occur up to approximately 1,860 pounds. 1 I 7 HPSI flow is indicated as zero, below about 65 2 8 gpm. And, in actuality, due to the shut-off head of the 9 pump, you can get flows of 20 to 30 GPM, up to about l',860 i 10 pounds. Why is this? It is because of a square root j i 11 extractor in the flow circuitry. It cuts off at a pressure I 12 or at a low flow it just cuts off because of the inherent 13 errors in the -- or problems with square root extractors -- l i 14 not errors, but just the biasing of square root extractor. i 15 Radiation monitoring systems in the control room. ~ t 16 They are not user friendly and they inhibited the monitoring [ i I 17 of trends. In fact, you -- in the control room, to use the 18 radiation monitoring system, you do not enter into that

l 1

19 system directly a channel number. You have to go to a j 20 conversion table and enter a code for that channel number, { j 21 and then you can look at the trend A radiation monitor. You 22 cannot trend a number of radiation monitors. a 23 Because of the operators' activity at that point I 24 in time and the difficulty in using this thing, they really f f 25 didn't use it to its best ability. That concludes'my part l 4 h ANN RILEY & ASSOCIATES, LTD. Court Reporters j 1612 K Street, N.W., Suite.300 Washington, D.C. 20006 (202) 293-3950 l 3 I

_.. _. _ _ _ _. _ _ _ _ _ _ _.. _.. = _ _. _. _. _ _ _. _ _ _. _ _.. ~ _. _ _ _. _. _ _. _ _ _. - 287 1 of the presentation. Are there any questions? 4 fI 2 MR. CARROLL: I want-to go back to the square' root i 3 extraction problem. Did somebody come up with a fix for: l 4 4 this? 5 MR. CATTON: Change the chip. That's not the probl'em. 6 MR. CARROLL: No, no, no. 7 MR. LINDBLAD: Is this a common mode failure in an { 8 analog system? I r 9 MR. KIRSCH: No, I think -- in answer to the l 10 question, I do not believe the circuitry has been changed. i i 11 To my knowledge it hasn't. If it has, Dick Bernier could 12 tell me. 13 MR. CARROLL: What is the range of these flow i i i 14 meters? Zero to what? 15 MR. KIRSCH: Zero to 200 and something gallons a d l. 16 minute I believe. 17 MR. CARROLL: Well, okay. You should be able to 18 see 65. 19 MR. KIRSCH: So, you are getting way down in the 20 low end. But, it really would not cause an operator any l 21 problem so long as he were to realize that the shut-off head i[ 22 of the pump is about 800, 1860 pounds and the -- you are 1 [ 23 going to get flows up to about that pressure, even though i 24 the circuitry tells you zero above 1800 pounds. It really l 25 shouldn't cause them that much difficulty. [] f ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 l-(202) 293-3950

~. 288 Hi 1 MR. CARROLL: Now, the only solution-I know of is. .f h 2 two flow meters -- a high range and low range or something 3 like that. Not a new problem around power plants. 4 MR. KIRSCH: No. 5 MR. DAVIS: How hig.. did the pressure get on the 6 secondary after the steam generator was isolated? 7 MR. KIRSCH: They were equalized about that time. 8 And, as I recall, they were equalized at approximately -- I 9 don't know the number. The primary pressure was down at 10 that point in time when they equalized. 11 MR. CHAFFEE: In fact, don't they have to get the i i 12 pressure in the primary down low enough, below the secondary 13 main steam before they can even think about closing the main l 14 steam -- J 15 MR. KIRSCH: Yes. That's part of the criteria for 16 equalizing, j 17 MR. CHAFFEE: Maybe you covered it. But, the l. 18 reason -- did you get into the reason why not recognizing 19 there is a small amount of flow from HPSI -- the 20 significance that has? i 21 MR. KIRSCH: The operators weren't trained that 22 this would happen in either the classroom or in the 23 simulator. That was another training deficiency. 24 MR. MICHELSON: I would like to go back to the ] 25 first bullet for a moment. Whoever designed the simulator l JJM RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 a

289 1 had to do it from the drawings of the plant. That -- if you 2 are making a simulator, it presumably simulates the plant. 3 And apparently when he did it he either missed the fact that 4 the alarms didn't lock in or he was working from drawings 5 that did show they locked in. Now, did you go back to ask nh 6 why the simulator locks in or seals in but the plant 7 doesn't? r 8 MR. CARROLL: It doesn't seal in. It is just that 9 the -- 10 MR. MICHELSON: It has to be clear. 11 MR. CARROLL: No. The radiation levels are high 12 enough. 13 MR. MICHELSON: No, no. But, I thought you said 14 that on the simulator, once you get the high alarm, it seals 15 in, it stays? 16 MR. KIRSCH: Yes, I did. 17 MR. MICHELSON: It seals in. 18 MR. KIRSCH: Okay. 19 MR. WILKINS: It remains in the line. 20 MR. MICHELSON: Yes, until you clear it with a 21 button. 22 MR. CARROLL: Is that because it seals in or 23 because -- 24 MR. KIRSCH: No, no, no. It doesn't -- it is not l 25 a seal in. The -- the assumption in the simulator is that j MRI RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 1

o e r i j 250 1 you have this leak and you have a high enough activity level l ) s 2 that the alarm comes on and because of the alarm -- 3 MR. CARROLL: It stays on. 7 i 4 MR. KIRSCH: -- activity level, it stays on. ~ 5 MR. MICHELSON-You are saying then, on a 1 6 simulator, it does not include the fact that alarms can go 7 away again, which was the case here at the plant that i e created the problem? i l 9 MR. KIRSCH: It could. The simulator can be i I 10 programmed to have the alarm go away. e l l 11 MR. MICHELSON: Sure. { 12 MR. KIRSCH: Yes, sir. j 4 i 13 MR. MICHELSON: And a good simulator design -- [ 14 MR. KIRSCH: Generally, that's not the way it was 'j 15 handled in a steam generator tube v.p*ure scenario in the i 16 simulator. I i 17 MR. MICHELSON: Well, I had thought the simulator 18 was -- this was not an engineering simulator. This is some 4 19 kind of a program for each event separately. I thought this 20 was an engineering simulation. 21 MR. KIRSCH: The simulator operator has a rather 22 significant amount of latitude that he can exercise in the - 23 - in the initiating of a particular scenario and the course 24 of a particular scenario. 25 MR. MICHELSON: Well, then that is something you ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washingtcn, D.C. 20006 (202) 293-3950

-.- ~ ~. -. - 291 j 1 might want to inquire into because then, if the operator has k 2 that much control then, of course, he is affecting training e 3 significantly. I thought this was an engineering simulation 4 and the operator didn't have to put in what the electronics 5 normally does. Most big simulators really do follow what i a 6 the electronics of the plant does. That is why you'-- i 7 MR. CARROLL: Yes. _But, you have to make some: 8 assumption as to how much activity is getting out. 9 MR. MICHELSON: The seal-in circuit was all I was i L 10 discussing. j n I l 11 MR. CARROLL: But, there is no seal-in circuit. 1 12 MR. KIRSCH: There was none. l j 13 MR. MICHELSON: There is -- the designer of the l l 14 simulator put a seal-in on it. 15 MR. CARROLL: That's not what it -- l 16 MR. MICHELSON: Now, he had to get that 17 information from somewhere. 5 l 18 MR. KIRSCH: No. It is not a seal-in, sir. It is ) l 19 not a. seal-in circuit on the simulator, nor is it a seal-in I [ 20 circuit -- the lock-in circuit on the plant. 21 MR. MICHELSON: Why did it stay on in the i 22 simulator? i 23 MR. KIRSCH: It comes on in the plant and is l-24 presumed to stay on because of the actual activity level at t i i 25 the time. j t l ANN RILEY & ASSOCIATES, LTD. Court Reporters l 1612 K Street, N.W., Suite 300 j Washington, D.C. 20006 j (202) 293-3950 j g l

m 292 1 MR. MICHELSON: You mean the board on the J 2 simulator -- the light stays on? 3 MR. KIRSCH: The simulator being a. digital machine-4 r 5 MR. MICHELSON.: Yes. i 6 MR. KIRSCH: -- wh'en you program.it in, if you 7 don't take that away, it will stay in. l 8 MR. MICHELSON: It will stay on. Right. 9 MR. WILKINS: Whether you want to call that seal-l 10 in, who cares? l 11 MR. MICHELSON: It is a seal-in. i 12 MR. CARROLL: A seal-in has a special function. - j I 13 MR. KIRSCH: Greg has got it. l l 14 MR. GALLETTI: This is Greg Galletti from NRR. I j 15 think the point that is important to stress is that in the j 16 simulator, when they do a steam generator tube rupture 4 17 scenario, it is expected that you are going to get one of . i 18 these alarms in. So, when they are going through the 19 scenario, when they get to that diagnostic logic. tree and 20 they are asked that question, at that point in time, they. l 21 will see one of those alarms. In the real situation, that 22 was not.the case.. 23 MR. MICHELSON: Well, all I asked was whether you i d i i 24 see that alarm still on the simulator if I looked back there 25 If minutes later? l, IJN RILEY & ASSOCIATES, LTD. Court Reporters 1612-K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 i I ..l

~ . -. ~.... .293 1 MR. GALLETTI: I couldn't tell you whether after l 2 15, but I can tell you when they get to that point-in the l 3 logic diagnostic. tree, which could be five minutes into the i q D 4 scenario, they will.have those alarms. l 5 MR. MICHELSON: I have no doubt of that. ~ - 1 6 MR. KIRSCd: Again, it isn't -- l 7 MR. MICHELSON: Otherwise, they would have caught- '1 1 8 it when they did the first time running. l i 9 MR. CATTON: What it really gets down to is j i 10 fidelity of.modeling in the simulator. l l 11 MR. MICHELSON: Yes. That's the problem. j 12 MR. CATTON: If the simulator thinks the level -' i a 't 13 goes down, maybe the light is going to go off. 1 [ 14 MR. SEALE: Well, but then getting to what l t 15 happened in reality. It is my understanding that the set 16 point for the alarm was based on a site boundary dose level' L 17 and not the level that might be expected if you had a leak J t 18 in excess of 41 or whatever that leak rate was,-which would. ] 1 i 19 be the threshold for the steam generator tube leak' exceeding l 20 the recharge pump delivery rate or whatever. . i 21 MR. KIRSCH: Dr. Seale is quite right. -The alarm 22 on -- in the plant at that time, which has since been [ I 23 changed, but at that time, was based upon this higher level. 'I { 24 With the activity level -- if you had a very clean primary 25 system and you had a small leak, this alarm -- the alarm on l i 1 i i ANN RILEY & ASSOCIATES, LTD, j Court Reporters l 1612 K Street,-N.W., Suite 300 .j Washington, D.C. 20006 (202) 293-3950 j 6, ,,,rm...m- ..~,,_,,....._..e .s - -- -- -mw

t l 294 'l p 1 the air ejector monitor could take a long time to alarm, a l E .t 2 very lono time. In' fact, with this level of activity in the l 3 primary at that time that they had the rupture and the 4 magnitude of the leak at the time of the rupture calculated ) 5 240 gpm, the calculation performed by the utility's own i i 6 engineering department subsequent to it, indicated that-it i 4 7 would be approximately 20 minutes before the condenser air l ) 8 ejector exhaust monitor would alarm. j e j 9 MR. CARROLL: No more questions for Dennis? f I I 10 [Ik) response.] ~ i i i 11 MR. KIRSCH: Thank you. l 12 MR. CARROLL: I really expected you, Dennis, to-13 blame the former resident inspector at Palo Verde for all of l 14 these problems. But, you didn't, huh? j i 15 MR. KIRSCH: I have better sense than that, j l I l 16 [ Laughter.] t I 17 MR. REESE: Can you all hear me all right? l 18 My name is Jim Reese, and I am the Branch Chief I l l l 19 for the Facilities Radiological Protection in the soon to Se l 20 defunct Region V. My purpose of my talk today is to talk ? I i 21 about some of the leak rate determination problems that the l l 22 licensee had and their methodologies during the tube ) 23 rupture. l. 1 i l 24 I am going to start off by looking at some of the l 25 history of the leak rate, going into the rupture. We are j l l i i j ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 l l Washington, D.C. 20006 j l (202) 293-3950 i 6 g. i -.~....

i 295 i 1 also going to review a little bit of the radiological 7 2 consequences that are going on in the RCS at this time. We 3 are going to look at their leak rate determination methods, ? l 4 and then look at some of their corrective actions-that they j 5 have done since that time. { 6 The FSAR in Chapter 15 analyzes for a steam 7 generator tube rupture and in that and also the offsite 1 i 8 radiological consequences, and in that analysis they utilize-l 9 an RCS activity of about 60 microcuries per gram. 10 At the time of the rupture, Palo Verde Unit 2 was l 11 actually operating with an RCS iodine activity of.13 12 microcuries per gram, so you can see there is a significant 13 difference in that. l 14 It is really important for two reasons, j i 15 One is that it shows that this event had very i 16 minimal offsite radiological consequences; secondly, it l-t 17 gave them problems in their leak rate determination methods. r 1 ( [ 18 In other words, it restricted the methods they could use l J 19 because they weren't getting enough activity across to the .l 4 { 20 secondary, as you would expect if you had a higher activity l 1 21 in the primary system. I 22 The first indication of a tube leak -- this may i l 23 not necessarily be the same tube -- but of a tube leak came 3 i es in July of 1992 when the licensee detected tritium in the I I L 25 condensate samples. The concentration of tritium in these i t ANN RILEY & ASSOCIATES, LTD. l Court Reporters l 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

. -~ . - ~.__ s 296 1 samples equaled about a gallon per day leakage. -Upon j 2 detection of that then the licensee initiated increased 3 monitoring of the condenser off-gas and blow-down radiation 4 monitors and also increased sampling. i 5 In December, 1992, Combustion Engineering sent a .j 6 letter to Palo Verde indicating that results of some tests' 7 performed in 1987 showed that their primary sample point for i 8 steam generator bulk chemistry, which was the-steam 9 generator hot-leg blow-down sample point, was being diluted 10 by incoming feedwater spilling over the center divider j i 11 plate. o 12 I have -- let's see. What are we looking at here? i I 13 Here is the hot-leg sample point down here and what happens I-14 is you have the feedwater coming in and spilling over this l i t 8 divider plate and it's giving them some dilution in there. l j 15 It~ This letter also at the same time recommended that j t l' .7 they change their sampling location to the downcomer up here l I 18 for bulk chemistry analysis. 19 In January the Site Chemistry Manager issued a l k t 20 directive to Chemistry personnel, and what he did is he i 6 21 changed the sample location -- { i 22 MR. CATTON: Is there any reason'that it takes 23 five years for information like that to get out? 24 MR. REESE: The information as I understand it was' l 25 available to the licensee. It was over in the Engineering i i ? ~ l i t I ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.H., Suite 300 Washington, D.C. 20006 (202) 293-3950

L l 297 ~! I section and for some reason it was not acted upon over 2 there. 3. MR. CATTON: We care about that sort of thing. 'i 4 MR. REESE: The Site Chemistry Manager issues a 5 directive out, changing the sample location for bulk a 6 chemistry from the hot-leg blow-down to the downcomer. 7 However, at the same time they maintain the sample location 8 for radioactivity at the hot-leg blow-down and-they did that l 9 for two reasons. 10 First of all, they felt it gave them a better 11 indication of radioactivity leaving the steam generator and 5 12 also provided them with a mechanism of predicting the 13 radioactivity loading of the condensate and blow-down I 14 demineralizers. 15 In February they hed indications that the leak 16 rate was increasing and the indications came in the form of l 17 detection of fission prodt ets in the hot-leg blow-down i 18 sample such as Iodine-131. When they got that, then they. l 19 increased, again stepped up their monitoring of the i 20 condenser off-gas and blow-down monitors. At the same time i 21 they also then increased the setpoints on the blow-dovrn i i i 22 radiation monitors. l l 23 On March 4th, they had a spike in the leak'and the 24 spike whipped from about 2 to 5 gallons per day up to about .l i 25 105 gallons per day and then over the next-three days it j k ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

298. i 1 gradually came back down and levelled out at about 20 to 30

)

2 gallons per day, where it stayed until the tube ruptured. ~ 3 On the 14th'the tube ruptured;-as Denny said. The 1 4 leak rate at that time was about 240, estimated to be about' 't 5 240 gallons per minute. l 6 At the time of the leak the licensee had five j 7 methods procedurally available to them-for leak rate 8 determination. There was a tritium activity in the 9 secondary plant, actually in a condensate; measurement of l I 10 fission prcduct activity in the steam generator blow-down; i 11 measurement of the fission gases' activity in the condenser j 12 off-gas and this is by grab sample; launching the condenser 13 off-gas radiation monitor readings; and finally measurement i 14 of boron in the steam generator secondary side. 15 However, because of the low activity they were 16 really only able to use these three methods here at the time l 17 of the leak rate. l 18 Go to the next slide first. 19 The first method the licensee was using at this' 20 time was actually tritium in the secondary and-the reason l 21 they were using this was very simple. It was the only i 22 radionuclide they were detecting at that time. j i 23 When we looked at the tritium, there was two i 24 problems we identified with that. First is that the l 25 equation they were using relied upon a continuous buildup of i ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 = (202) 293-3950 1

.~... _ 299 1 tritium in the secondary side and it also at the same time .2 because it did this, it did not consider the losses in the i 3 secondary system. i 4~ So what effect did this have on it?.When we're 5 relying upon tne continuous buildup in the secondary side, i 6 once the tritium reached equilibrium value, then your leak 7 rate determinations based on the'r equation would give them ] l' 8 false readings and in some case actually gave them negative 9 leak rates because -- if you'll.put the next up -- this is' 10 their equation they were using at the time. t 11 They relied upon two samples, the first sample and 12 the second sample taken about two hours apart. If you hit l 13 equilibrium values, then this sample may end up being 14 negative -- being lower than this sample and you end up with } 15 a negative number and thus a negative leak rate. That was i 16 the problem with it. 11 7 You also see in here that there is no accounting i 18 for a loss out of the secondary system. I I '9 MR. SEALE: I vaguely remember this was right i 20 before a planned shutdown, wasn't it? j 21 MR. REESE: Yes. About a week before, if I 22 remember. 23 MR. SEALE: Okay, so the boron levels were way I 24 down? 'l 25 MR. REESE: Yes. lj L l ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 j (202) 293-3950 t l

, ~. l 300 a 1 MR. SEALE: Because of end of core life. 2 MR. REESE: That's correct. 3 The second method, then, on about March 3rd, the 1 4 licensee had enough activity in the' hot-leg blow-down, the ) 5 switchover to the iodine method. Our review of the iodine { 6 method again brought up two areas. ] 7 First of all, they did not account for the j i 8 dilution that Combustion Engineering had informed them of; 2 3 9 secondly, they were not accounting for hideout, iodine l 10 hideout in the secondary, which is a tough thing to model in j i 11 itself. f '12 The 3rd method they were using.was condenser off-1 ? i 13 gas radiation monitor readings. During the event it was r 14 discovered that these monitor readings were off by about a i 15 factor of 6. Subsequent investigation by the licensee t } 16 afterwards indicated that they had a detector and photo j l 17 multiplier tube degradation and they speculated that this i 4 18 was caused by heat tracing that they put around the sample l 19 lines to keep moisture from getting in, f 20 Finally, we looked at their procedure. In their 21 procedure we identified three areas that could have been ? l 22 improved. i 23 Firstly, they did not specify a hierarchy of i l 24 methods to be used -- in other words, do you want to use, j t 25 which is your primary method do you use first. There was no i ANN RILEY & ASSOCIATES,'LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 7 (202) 293-3950 j 1 l 1 - _ =- 1

301 1 requirement for verification by using a different method of' ~ l h 2 your leak rate determinations and also it did not fully. I 3 delineate all the limitations of the method such as with ] 1 4 tritium it didn't specify that when you reach equilibrium 5 you could have problems. 6 MR. DAVIS: What would be wrong with using N-16 to 7 monitor that? I realize it's half-life is pretty short.but j 8 it seems like it still might be -- l 9 MR. REESE: Well, the short half-life would .f i 10 preclude sampling for N-16, obviously, but for monitors that 11 is a good way to go and the licensee is now looking at 12 putting N-16 monitors on their steam lines. j l 13 MR. DAVIS: Oh, really? i 14 MR. REESE: Yes. I 15 MR. DAVIS: Good. 16 MR. WIGGINS: This is Jim Wiggins from the '7 Division of Engineering, NRR. 'j i 18 N-16 monitors are fairly commonly used outside '19 this country for main steam line monitors and it's growing l 20 inside this country. Nationally people are beginning to i 'I j 21 install N-16 and N-16 monitors and steam lines can give.you a 22 real-time online leakage detection at very low levels. f 23 There are some problems with it. It's not very 24 useful, it's not useful at all at hot standby or i 25 nonoperating conditions and it's not very useful at ) h ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

302 f 1-escalation and power de-escalation periods:when it somewhat 2 requires an equilibrium to get a reliable leak rate but it [ 3 will still tell you something different is going on_in 4 there. j 5 When we get to the final part of the presentation, 6 we'll talk a little bit about -- I'll try to address.a i 7 little bit about what the role of leakage detection we think j 8 plays now in how you manage these steam generator degraded j f 9 conditions. 10 MR. REESE: Prior to the restart of Unit 2, j 11 licensee made several changes in their program. 12 First of all, they revised the procedure and the 13 procedure now does give the hierarchy, does specify { 3 i 14 limitations and also talks about comparison of samples in 15 there. i i 16 They have also set up what they call a leak rate .} t 17 plan and this leak rate action plan has three action levels. 18 At leak rates less than 10 gallons per day, they 19 begin daily calculations of the leak rate and also frequent, t 20 no time period specified but frequent monitoring of i i 21 radiation trends to see what is going on with the leak rate. i i 22 MR. LINDBLAD: Mr. Reese, is it true that these j i 23 corrective actions are limited to your scope of the 24 presentation, is that right? 25 MR. REESE: As far as I know, yes. ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 -l

.~.... .-... -. - ~.. -..-- 303 I e 1 MR. LINDBLAD: But they are not encompassing 2 corrective actions but just the chemistry sampling? 3 MR. REESE: Right. 4 MR. LINDBLAD: Thank you. 5 MR. REESE: At 10 to 50 gallons per day, if the [ 6 leak rate, first of all, increases by 50 percent in a 24-l L l 7 hour period or if it is greater than 25 gallons per day, the I f 8 Chemistry organization, Engineering and Operations get' -I 3 9 together to evaluate continued operation of the unit. i s i 10 At 50 gallons per day, the Shift Supervisor i 11 initiates an orderly shutdown of the unit and then notifies { } 12 Management. 13 That ends my presentation, j i l l 14 Any questions? l l 15 MR. WILKINS: Do you notify the NRC at 50 gallons j n 5 16 per day? i s-l 17 MR. REESE: I think at plant shutdown they would ~ i 18 notify the NRC, yes. 19 MR. CHAFFEE: Okay. While we are changing i ? l 20 . speakers, you had asked earlier about the NRC's response to j 21 the event at Palo Verde and we're just going to include some i I { 22 information. j i i l~ 23 Apparently we made the decision to go to the i L 24 standby mode within 22 minutes of being notified of the j i i 25 event and although there was -- j t i i i I ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 t 4 l Washington, D.C. 20006 (202) 293-3950 i e y,v,-r~, e-e n --, w -,r ,--,+.e,r--n,,e-ee n-w ,-+--nm r- ,--,--+r.,,, - ~ - -n 4

..,, ~,... ~ __

n. - -.. _.

i 304 1. MR. CARROLL: And that means people get called or 3 2 alerted that they may have to come in but -- P k 3 MR. CRAFFEE: Yes, but in fact typically we would l .I 4 notify some people to come in even before we made that l i l 5 decision and in fact, even though we weren't able to get a .i i i 6 full complement available due to the storm that was going i i f l' 7 on, they did have within an hour a response team including' 8 ET members and Reactor Safety Team members that were ini i, 9 place and in the Operations Center in Headquarters, as far-l 10 as Headquarters response goes. l i ) 11 MR. WIGGINS: Just to clarify, when he said j 1 4 12 " standby mode," that is Ed Jordan took the agency to standby i 13 and what that ends up with is a full complement of incident j i ( 14 responders in the Regional Incident Response Center which l 15 include the full spectrum operations, radiation protection, 16 state liaison, government liaison -- the whole waterfront is t 17 covered in the region, but in Headquarters there is more of l I 1 18 a skeletal staff. Some key people would be at least i l 19 attempting to get in. f 20 That's the first move before the agency would i i i 21 escalate up to some part where the region would be stripping J F a 22 down and sending a site team. By that time the Headquarters l 23 organization would be fully manned and would have to take I 24 over the incident, so it was the first historically official r 25 stage of NRC mobilization. There's some others, there's l i l i j ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 j' (202) 293-3950 a. 1 1 l t

_m. t 305 I ( 1 another stage that's actually less than that that it's more l 2 of a monitoring role. That isn't what was going on here. 3 This was a full standby operation. 4 MR.. CARROLL: I remember very well, since I was i l 5 snowbound back here. It is amazing anybody got in. { 6 MR. WIGGINS: Yes. And there were other things i 7 going on as a result of that snowstorm, if it is the l 8 remember. I was in Region I at the time, and there were a f 9 number of plant problems as a result of the snowstorm that 10 we were handling out of that Region. So, it was a busy 11 weekend. 12 MR. KARKOSKI: Good morning. My name is Ken I 13 Karwoski, and I am going to be talking about the root cause 14 of failure for the Unit II steam generator tube rupture. I 15 will primarily discuss the materials aspects, but I would 16 like to point out that you should be aware that the staff's 3 J 17 safety evaluation primarily relied on a systems' safety l t 18 analysis to address the overall safety significance of the i 19 steam generator tube-rupture to justify operation for the 6-20 month interval. 1 21 Palo Verde Unit 2 has two System 80 steam j 22 generators. There are approximately 11,000 tubes in these 23 steam generators. I am going to be referring to various 24 support structures during my presentation. There are nine l 25 support plates in the steam generator. The top two are i i ANN RILEY & ASSOCIATES, LTD. Court Reporters l 1612 K Street, N.W Suite 300 Washington, D.C. 20006 (202) 293-3950

r 306 i i 1 partial egg crate supports. The bottom support is a' drill I fh 2 tool hold support. 3 Other support structures that I am going to be { i 4 referring to are the bat wing. support and also the vertical j 5 straps. I am going to limit my discussion to the hot leg-t 6 side of the steam generator because that is where the i 7 majority of the degradation was found. These supports -- 8 the top two supports are 08H and 09H, and that's where the j 9 primary -- most of the degradation observed-was in these 't 10 areas. I 11 Let me point out one other thing. There are only i 12 three plants with C System 80 steam generators. Those are j .I 13 the three Palo Verde plants. These steam generators have j 14 their own thermal hydraulic characters. So, at this time, t W 15 we believe the problem is unique to Palo Verde. Some-of the I 16 unique characteristics of these steam generators are they f 17 have an economizer region down here, which pre-heats the i feedwater prior to entering the evaporator section of the 18 j 1 19 steam generator which, as I will get into, promotes dry-out l 20 in the upper portion of the tube bundle. l 21 MR. CARROLL: Do you know if System 80-Plus' steam i 22 generators are the same as this or different? 23 MR. KARWOSKI: We have been talking with CE about 24 that and we are aware and we are following up on that. 25 MR. CARROLL: Are they the same? l ' f ANN RILEY & ASSOCIATES, LTD. Court Reporters ) 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 i - -.... _. ~,.. _. -.,,.., - -... - _ _., _ - -. -,. -. -~,~. _ _--.,,. - --.~ -., -.,. -. - ~,

t l J 307 2 1 MR. KARWOSKI: They are very similar. I couldn't 2 say if they were the same or not. 3 MR. SEALE: Larger volume. i 4 MR. CARROLL: Yes. That's right. 5 MR. KARWOSKI: Okay. The primary mode of f 6 degradation observed at Palo Verde Unit 2 prior to the tube i 7 rupture was primarily wear. The licensee was observing wear I 8 in the upper egg crate portions, at the bat wing, at the i 9 vertical straps and also in the cold leg corners of the l 10 steam generator. However, the licensee did identify several i l 11 axial indications in the outage just prior to the tube 12 rupture. Six of the seven axial cracks identified at that 13 time were at the O1H support. Outside diameter stress, 14 corrosion and cracking at the first -- at support plates is 15 not that uncommon. However, the licensee did identify one i 16 axial indication in the upper portion of the tube bundle 1 17 just above the 098 support. This indication was l t 18 approximately 1.07 inches long and 76 percent through-wall. t i 19 As a result of that indication, the licensee did expand { i 20 their inspection scope to ensure that similar indications i 21 were identified; however, they did not address the potential 22 safety significance of that. indication. 23 MR. LINDBLAD: So, was that a sampling inspection? t 24 And what fraction of the tubes were inspected? 25 MR. KARWOSKI: In the inspection prior to the I 1 f ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 j Washington, D.C. 20006 i (202) 293-3950 i' .a.

.. ~.. ~. ~. ~ 308-1 refueling, I,would say essentially did a hundred percent j l. 2 inspection in that area. 3 MR. MICHELSON: How much service time was on the i i 4 tube that failed? l 5 MR. KARWOSKI: The plant has been in commercial 6 operation since approximately 1985. i 7 MR. MICHELSON: Okay. l t 8 MR. KARWOSKI: So, about eight years. 9 MR. LINDBLAD: This was an. eddy current 30 inspection? I '1 MR. KARWOSKI: Yes. 12 MR. LINDBLAD: That was? l 13 MR. KARWOSKI: I will be getting back to that in l 14 detail. 15 MR. CATTON: Are you going to talk about the.cause i' 16 of the wear? i 17 MR. KARWOSKI: Of the wear? No. That was just to l t t l 18 give you a little background. j 19 MR. DAVIS: Were any tubes plugged atLthis point? = a 20 MR. KARWOSKI: Oh, yes. There were approximately 9 i I 21 -- in steam generator 2 of Unit 2 there were approximately 22 200 tubes plugged prior to that roughly. i 23 MR. CARROLL: For what reason? j i 24 MR. KARWOSKI: Primarily wear. l J 25 MR. DAVIS: Based on the inspections previous to i ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 2 Washington, D.C. 20006 (202) 293-3950 L.. i

s k V a 309 a. i 1 that? -2 MR. KARWOSKI: Right. Correct. 3

Okay, I think --

) i 4 MR. CARROLL: Had the unit ever had an inoperation i 5 tube rupture before? s a 6 MR. KARWOSKI: No. This'was their first. tube 7 rupture. They did have other leakage primarily from plugs, 8 but this was their first tube rupture. That was minor l l 9 leakage. i i 10 MR. CARROLL: Okay. l 1 i 11 MR. KARWOSKI: One other thing I would like to l i 12 point out There was this one axial indication in the upper 13 portion of the tube bundle called at that time. After the l l 14 tube rupture, they went back and reevaluated some data. 15 They reclassified two other axial indications up in that j i 16 upper portion of the tube bundle. They have been classified l 17 as potential loose parts indications and they subsequently f 18 reclassified them as axial indications. I 19 MR. CATTON: What does this wear'look like? Is it l 20 because the tube is moving in the supports or something? I i l 21 MR. KARWOSKI: It's usually because of contact due l- - 22 to support plate or some support structure. Correct. i 23 MR. CATTON: But there is some motion? l t 24 MR. KARWOSKI: Yes. Enough to cause the wear, l 'I 25 right. I i I I I I f ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 i Washington, D.C. 20006 (202) 293-3950 l f 4 .m_,,_,..,,,,,,----,,_,,..-o,,,-,,.-,,-,,,,,-

t i 310 ~ 1 MR. DAVIS: This wasn't a denting problem -- l 2 MR. KARWOSKI: No. Palo Verde 3 MR.-DAVIS: -- that has been seen in Westinghouse? i 4 MR. CATTON: That was like a vibration problem. 5 MR. KARWOSKI: -- has egg crate supports. 6 MR. DAVIS: Oh. Okay. 7 MR. KARWOSKI: In addition, there are stainless 8 steel supports so they have not experienced any significant ) 9 denting, as you are referring to. 10 MR. SHACK.: This is' threading wear. I mean, it is 11 vibrating within this? l 12 MR. KARWOSKI: Yes. 13 MR. CATTON: Okay. That's an interesting problem. l 14 MR. KARWOSKI: Yes. That is another problem. 4 ~ 15 But, as was mentioned earlier, one week prior to a scheduled l ) 16 refueling outage, there was a 240 gallon per minute steam l 37 generator tube rupture in steam generator 2 of Unit 2. The {, 18 ruptured tube had a two to two and a half inch axial l 4 19 fishmouth opening. The entire crack length of the l 20 indication was approximately eight inches long. 21 MR. CARROLL: What is the idea of'these tubes? l 1 22 MR. KARWOSKI: Excuse me? 23 MR. CARROLL: The OD? 24 MR. KARWOSKI: The OD is three-quarter inch. Wall. 1' 25 thickness is about 42 mils. ANN RILEY & ASSOCIATES, LTD. Court Reporters l 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 m. 3 - +, -m.3 -, - l

lt 5 e -I i 311 1 ) l As mentioned previously, the indication in the 1 e i 2 prior cycle is located right above the 098 support. This t- ^ 3 indication was located right below the 098 support. l f 4 MR.. SHACK: It's eight inches long, so right below I l l' 5 means that the tip is -- i. l 6 MR. KARWOSKI: Is right below'-- about three or j l' l i. 7 four inches below the bottom of the 098 support. .i L i 8 As a result of this indication, the licensee j i l 9 reviewed the eddy current results from the ' previous ~ l l l 10 inspection. When they reviewed those records, they could 4 l 11 not discern any detectable degradation. So, essentially, 12 this crack went from no detectable degradation to a tube 13 rupture in 15 months of operation, indicating a fairly-high f l I' i { 14 growth rate. l 15 In addition, there was measurable primary to j l 16 secondary leakage prior to the event. However, the licensee j i 17 could not conclusively identify this leakage or contribute f l 5 I 1 i 18 this leakage to the ruptured tube. In addition, in the j 19 hours prior to the event, there was no conclusive evidence j 20 of a slow stable increase in the leak rate. The j

I 21 significance of this is this tube may not have leaked before i

t j 22 it broke, thereby, it would not provide indications of j 23 precursor leakage indicating a potential failure is 1 24 imminent. 25 MR. DAVIS: I thought we did here that there was a ANN RILEY & ASSOCIATES, LTD. l Court Reporters j 1612 K Street., N.W., Suite 300 Washington, D.C. 20006 l (202) 293-3950 l .,..,.. _,.. - _ _. ~ _ _ _.. _ _ _ _ _ _ __ _,.______.._____ _____._-

a i 312 1 rather significant increase in leakage prior to the event. 2 MR. KARWOSKI: There was leakage prior to the 3 event, and it was fluctuating. There was an increase 1 I 4 approximately three days prior to the event, however, the j i 5 licensee could not attribute that to that tube. The leakage 6 in the last two days prior to the event was actually 7 decreasing from that spike. l 8 MR CHAFFEE: Also, the leakage increase that' l 1 9 occurred before the event that we talked about where it went i 10 up to -- I think it was 105 gallons per day,.the licensee l l 11 didn't recognize that at the time. I think the results of 12 their analysis of the results only indicated the leakage i 13 rate -- I think it was increasing from a couple of gallons j 14 per day to like maybe up to 10 gallons per day. 15 MR. KARWOSKI: Yes. 16 MR. CHAFFEE: So, what they saw was an increase, ] I 17 but only like from one or two gallons per day to 10 gallons r 18 a day, as opposed to after the fact looking back. Really + i 19 what they had were indications indicating they went from. l I t 20 about 20 gallons per day to about 105 gallons per day. 21 MR. DAVIS: But it is still arguable whether that 22 is attributable to this particular tube or not. l t 23 MR. CHAFFEE:

Yes, l

24 MR. KARWOSKI: That is true. -j .} 25 MR. DAVIS: But, didn't they inspect all.other l [ t t' i 4 ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 i

i 313' 1 . tubes after the event? 2 MR. KARWOSKI: Yes. The reason that they could j 3 not conclusively identify that is for several reasons, j 4 There were other through-wall cracks that were identified l 5 during the inspection and also the fact that when they did a 'l 6 pressure test prior to restarting,.they identified several 7 leaking plugs. And so the leakage could have been from the i e plugs. It could have been from other cracks. So,'you j i 9 cannot conclusively say that the leakage was from that l r 10 indication. I 11 MR. DAVIS: Thank you. i 12 MR. WIGGINS: This is Jim Wiggins again. I think 4 13 I just want to emphasize a point here too. You would i 14 certainly like, from an operational point of view, and even f 15 from an engineering point of view to have a steam generator l t 16 rupture play out as a small leak that you then see increase'

5 17 before break.

One thing that is happening here at Palo j i 18 Verde, and it is not uncommon, is the middle regime doesn't ? P 19 occur. You go from small leak to break; you don't go from l 20 small leak to bigger leak to break. Then there are some l J i 21 ramifications more generally in the need for better leak l 22 detection, as a whole, in these PWRs, and a more aggressive 23 approach in terms of emergency operating procedures and the-l 1 24 ability to cope with an event. Most of our regulatory i l-25 direction at this point, and you will hear that as we go l l l ANN RILEY & ASSOCIATES, LTD. l Court Reporters L 2612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 I

d 314 1 further on from Palo~ Verde is directed in those areas. ~ 2 MR. KARWOSKI: I would like to now talk about the 3 inspections that the licensee did during.the inspection. 4 The licensee primarily relied on eddy current testing to j 5 inspect a hundred percent of the tube bundle. They did a j 6 hundred percent bobbin coil inspection. They also did a 4. 7 considerable number of motorized rotating pancake coil 4 j f [ 8 inspections. Bobbin coil is typically used to rapidly scan i 9 the tube for defects. ) 10 The MRPC, or motorized rotating pancake coil 11 probe, is typically used to further characterize indications i i 12 identified by the bobbin coil. However, as the licensee { 13 proceeded in their inspection, they began to notice a number i i 14 of defects that were identified only with the MRPC and not 4. 15 with the bobbin coil. As a result, in the area of interest, l j 16 which I will describe shortly, they primarily relied on the ] 17 MRPC to identify the indications. j t 18 MR. CATTON: What is MRPC? t 19 MR. KARWOSKI: Motorized rotating pancake coil l 20 probe. It is a much more sensitive probe for certain types 21 of defects. a 22 As I mentioned, as the inspection proceeded, the 23 licensee identified an area where a disproportionate number I i 24 of indications were being identified. This area is referred l 25 to as an arc. And it primarily consists of tubes in the l i ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 i (202) 293-3950 I - -, _ _,,,, m ..--.,m ,,,m. ..,,,........-..,...,,r..,y>

315 1 outer periphery of-the tube. bundle. This arc is also 2 limited in an axial extent. The majority of the indications N 3 were being found from the 08H to the first vertical strap on ] I 4 the hot leg side. So, indications were being'found within 5 the support plates in the free span between the -- and free 6 span between the different support stlactures. l 4 i 2 7 As I mentioned, the --'they were finding a 1 8 disproportionate number of indications in this area. As.a J 9 result, they tried to determine some type of physical i 10 explanation of why this phenomena was occurring. j i 11 They performed a thermal hydraulic analysis which l 4 f 12 indicated that the upper portion of the tube bundle, from 13 the 07H support to the bat wing, was highly susceptible to 14 contaminant accumulation or deposition on the tubes. This 15 is a result of dry-out in that region of the tube bundle. 16 As I mentioned at the beginning of my presentation, they l I 17 have this economizer region which allows the water to be 18 preheated prior to entering the evaporator section, a ] t 19 resulting in dry-out in the upper portion of the bundle. I 20 As the inspection proceeded, however, they began i i 21 noticing indications outside the area that the thermal 22 hydraulic analysis predicted was susceptible to accumulating i 23 these deposits. As a result, they had to rely primarily on I i 24 the inspection scope to identify an area of interest. Their 25 inspection plan primarily resulted in performing MRPC i i l ANN RILEY & ASSOCIATES, LTD. Court Reporters i 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 i

316 1 examinations within the arc to ensure that they had bounded 2 the problem. They had done two things. If they had found 3 an indication adjacent to where they -- they expanded the 4 arc. Excuse me. Let me start over. They expanded the arc 5 as necessary to provide a five-tube buffer between the last 6 indication and the edge of the arc. That would ensure that 7 the problem was bounded radially. In-addition, to ensure I 8 that nothing was happening out in this region, they i 9 performed random MRPC examinations from the 08H support to 10 the first vertical strap. 11 MR. CARROLL: Now, the line on your tube map'is. 12 not a physical line, it's -- or it is not something physical t- ) 13 in the steam generator. i 14 MR. KARWOSKI: Right. i i 15 MR. CARROLL: This is the line they drew as a f d 16 result of their inspection program? i 17 MR. KARWOSKI: That's right. But, I would like to 19 point out that their thermal hydraulic analysis indicated j 4 19 that this portion of the tube bundle up high, above the 07H l i 20 support was susceptible to deposit accumulation, which is a 21 contributor to -- 22 MR. CATTON: Is that because it showed that there l 23 was a higher void fraction there or something -- I mean, i 24 more 25 MR. KARWOSKI: There was a transition to a film f l i I ANN RILEY & ASSOCIATES, LTD. l Court Reporters 4 1612 K Street, N.. W., Suite 300 Washington, D.C. 20006 (202) 293-3950 i i ..*.n. . _... _ _., ~....... -. _ _ _,,. ~. ~ m...m.. _.,,. ,r-,4 ,-.--e....,~,-+-,.

~ = 317 1 boiling occurring in that region. And, as a result, the () 2 tubes were drying out and any contaminants in the bulk water j 3 were being deposited on the tube. .j 4 MR. CARROLL: How good is their feedwater bin? 5 Have they had a lot of condenser leaks? l I 6 MR. KARWOSKI: In that outage, they did not have j 7 considerable condenser leaks. They primarily prescribed to 8 the EPRI guidelines. As I get into the root cause 9 evaluation, I will describe a little bit about their I -{ 10 chemistry and what the conti 'iting factors were. In t 11 general, they followed the industry guidelines on water i i 12 chemistry. l 13 As I was saying, they performed random MRPC 14 examinations out here to ensure that the problem was j ,j 15 bounded. The random inspections do not reveal any axial 16 indications in that portion. 17 In addition, to ensure that the problem was l ) 18 axially bounded, the licensee inspected below the 08H 19 support. They found a few indications there, but those 20 indications were identified with the bobbin coil, and the 21 licensee believes they bounded the problem. 22 To address the root cause of failure,.the licensee 23 pulled eight tubes during this outage. As a result of the 24 metallurgical analysis, they determined that the root cause 25 of failure was outside diameter initiated, inner-granule + ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 i i

L V i 318 i i, 1 attack, inner-granule stress corrosion cracking due to tube-i i l 4 2 to-tube crevice formation. .l g, ?, s 3 Crevices at the support plite'and in the tube l 1 1 4 cheet are well-known, and people are familiar with those. -j [ 5 But, what the licensee is postulating is that:the1 tubes are i 1i 6 actually coming closer together. And due to the potential l' \\ 7 for contaminants to accumulate in the upper portion of the I l 8 bundle, they are forming a crevice up in that region. l 9 MR. CARROLL: Meaning? F i j 10 MR. LINDBLAD: I have trouble with the word i 11 " crevice." Is this a gap that is bridging? j 12 MR. KARWOSKI: Essentially, by crevice, what'I -t 13 mean is the fact that some of these tubes are actually -- as 14 I get into ith they -- from the metallurgical examination, l 1 j 15 they identified that several tubes are bowing. They also i s l 16 observed that visually during other inspections. l 17 MR. CARROLL: Bowing and then coming in contact? I l l 18 MR. KARWOSKI: Not necescarily coming in contact, l l 19 but narrowing the gap and then, because of the increased 20 susceptibility of deposit accumulation up in that bundle, 21 these deposits can tend to bridge that gap. I s 22 MR. CARROLL: Got you. i i f i 23 MR. KARWOSKI: And then that is like a j i l 24 concentrating. 25 MR. SHACK: Can they visually see these deposits? d E i i i f I j ANN RILEY & ASSOCIATES, LTD. Court Repcrters ~ 4 i 1612 K Street, N.M., Suite 300 s Washington D.C. 20006 (202) 293-3950 3

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l Lj 319' ~ MR. KARWOSKI: Yes. After they pulled some of.the 1 2 tubes, they did video i.nspections, and they could go -- they 3 went up there with the video probe and actually saw the j 4 deposits on the tubes and also the narrowed space.in between i l 5 the tubes. l 6 MR. SHACK: I see. _i 7 MR. KARWOSKI: In addition, their eddy current 8 inspection, for several of the deposits identified that the n 9 deposits tend to be paired -- another indicator that maybe -l 3l' 10 these two -- that these-deposits are actually bridging the. ] l 11 twr tubes. 2 l 12 In addition, the metalography -- from the 13 metalography they determined that the attack was in an i 14 alkaline to caustic environment. This is primarily based on i i i 15 chromium depletion at the crack tips. In addition, they 'l L j j 16 noticed sulphate and reduced sulfur associated with the i l 17 crack tips. The sulfur is believed to accelerate the rate l 18 of corrosion and to be a contributing factor. The sulfur t l 19 comes primarily from resin which was identified by visual i I 20 inspection of the steam generator. The licensee has had l l 21 historical -- or has had problems with retention elements on 22 two of their condensate demineralizers. And that is the 23 source of the sulfur. 24 MR. CARROLL: Now, when you say elevated sulfur j 25 levels, you mean elemental sulfur? i i h ANN RILEY & ASSOCIATES, LTD. Court Reporters t i 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 (202) 293-3950 t

l 320 l 1 MR. KARWOSKI: No. Actually, some sulfur would be 2 expected, but elevated meaning more than normal. '{ 3 MR. CARROLL: No, no. 4 MR. SHACK: Do you mean sulphate, not elemental 'l 5 sulfur -- some sulfur compound? You haven't really j 6 determined what compound? j 7 MR. KARWOSKI: Well, there was sulphate and some i 8 reduced sulfur. 9 So, in summary, the root cause was due to tube-l 10 to-tube crevice -- was due to inner-granule attack, inner-j 11 granule stress corrosion cracking due to tube-to-tube 1 12 crevice formation. The deporits in the sulfur and the l I 13 environment led to a rapid attack. In addition -- j i 14 MR. LINDBLAD: Do these deposits build up between 15 tubes, but not between the egg crate and the tube? i i 16 MR. KARWOSKI: Primarily between tubes.

But, j

i 17 there are two types of deposits. There's the general i 18 scaling which occurs throughout the tube bundle on all 19 tubes, and is pretty common throughout the industry.

But, l

l 20 these deposits are more like ridge-like deposits, and these 21 are primarily forming in the upper portion of the tube 22 bundle. 2 23 MR. LINDBLAD: But you don't see the deposits in i 24 the egg crate area where there are even closer supports to 25 tube? j ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

'I s 321' 7L i 1 'R. KARWOSKI: There were no deposits that.I can j M 1 l 2 remember' identified inside the egg crate -- not the ridge- ? 3 like deposits. l 4 t 4 MR. LINDBLAD: And this is from. external physical j i 5 inspection rather than eddy current inspection;-is that l j i 6 right? i. 7 MR. KARWOSKI: Well, the -- there were some visual I l 8 inspections, and there were also some -- but, the visual ) 3 9 inspections were limited. So, the eddy current can detect I 10 some of these deposits. So, there is a combination of the j j 11 two. 12 MR. LINDBLAD: But, the egg crate supports may { 13 hide whatever deposits may be there in eddy current j 14 inspection? -l 15 MR. KARWOSKI: Yes. From my. recollection of j t 16 seeing the videos, I do not recall any of these ridge-like 17 deposits being in this. j i 18 MR. CARROLL: So, the bridging was happening at j t. 19 mid-span kind of stuff? j 20 MR. KARWOSKI: Yes. The bridging was primarily up l i l 21 in here, in these regions here. j i 22 MR. SHACK: But the big crack is three inches j n 23 below the OBH plate? l l i 24 MR. KARWOSKI: Below the 09H. i 25 MR. SHACK: The 09H. I i ANN RILEY & ASSOCIATES, LTD. Court Reporters j i 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 i (202) 293-3950 i 1 j

l 322 1 MR. KARWOSKI: In the free span between. 2 MR. SHACK: You are seeing deposits above and 3 below the 09H plate, but not within the 09H egg crate 4 itself? ~I 5 MR. KARWOSKI: From my recollection of that, yes. 6 MR. DAVIS: Excuse me. What is the pressure in I 1 7 these tubes? 8 MR. KARWOSKI: It's a triangular pitch tube sheet 9 i 10. MR. DAVIS: Right. 11 MR. KARWOSKI: -- and there is about a quarter l 12 inch spacing between the tubes. i 13 MR. DAVIS: At the closest wall-to-wall dimension? i i 14 MR. KARWOSKI: Yes. 15 The licensee also, as they were doing the f 1 16 destructive examination, identified that the ruptured tube ) 17 had a microstructure not typical of the high-temperature 18 annealed tubing. This is believed to have contributed to 19 the rapid failure of this tube. In addition, there were two 20 other tubes that were identified, which could be 21 characterized as a substandard microstructure and resulted j 22 in rapid crack growth. 23 In addition, the licensee identified several 24 surface scratches which could lead to more rapid crack l 25 initiation. l l = l ANN RILEY & ASSOCIATES, LTD. 1 Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

323. 1 MR. LINDBLAD: Excuse me, Kenneth. But,.these J ) '2 tubes that are in the arc in manufacture had to be made of i 3 longer tube material'than the remainder of the bundle. Is 4 there anything in terms of the production method-that might j i 5 have led to the sensitivity? j II 6 MR. KARWOSKI: The licensee looked =at-the 1 l 7 fabrication records of the steam generator and from that. i 8 they could not come up with anything conclusively. =! 9 MR. LINDBLAD: But all of the tube material was j i 10 the same -- the inner ones were just cut short, compared to 11 the outer ones? I 12 MR. KARWOSKI: Well, there were different heats of i 13 materials within the steam generator, so it was not all from 14 one heat. l 15 MR. CARROLL: So, when we first heard about this' 16 there was some suspicion that the pilgering process that was l 17 used to fabricate these tubes might have played a role? t 18 That has been subsequently discounted? i 19 MR. KARWOSKI: The problem with the pilgering is j I l 20 an inspectability issue. Pilgering tends to make the eddy 21 current very noisy, and it is very difficult to pick out 22 flaws. So, that was the concern of the pilgering. 23 MR. CARROLL: It would seem to me it would leave p 24 more residual stresses also then conventional drawing. l 25 MR. KARWOSKI: I am not certain about that. l I i ANN RILEY & ASSOCIATES, LTD. I Court Reporteis 1612 K Street, N.W., Suite 300 t 2 Washington, D.C. 20006 (202) 293-3950 I e .,e w =.,. _.,,, _

. _.... ~.. - .] 324 1 MR. CARROLL: Okay. 2 MR. SHACK: Do you know what the heat treatment 3 was on this tubing? Was this a two-step heat treatment? 9 4 MR. KARWOSKI: I'm not. 5 MR. CARROLL: I guess it came as sort of a 6 surprise to me that they are into film boiling up at the top 'l 7 of the bundle. Is that charar eristic of all steam i 8 generators? 9 MR. KARWOSKI: Well, their thermal hydraulic 10 analysis indicated that there was a transition to film 11 boiling occurring in that upper portion of the bundle. As I. ] 12 said, the design of the System 80 steam generators is 13 unique. j l 4 14 At a hundred percent power, as this slide shows, i l l l~ 15 approximately 90 percent of the feedwater comes in at the 4 l I 16 top of the tube sheeting and can be preheated prior to j 17 entering the evaporator portion and only 10 percent of the I i 18 flow enters up at the -- l i 19 MR. CATTON: What's the recirculation ratio on the 20 steam generator? 21 MR. KARWOSKI: The recirculation ratio is 22 approximately three to one, which is a little lower than. l t i 23 typical steam generator -- recirculating steam generators. 24 MR. WIGGINS: I guess Combustion Engineering has 25 indicted that it is low relative to the rest of their fleet? 4 l

l. '

ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 L Washington, D.C. 20006 (202) 293-3950 i I

.~ -~ n n, -... ~ _., E 325 1 1 MR. KARWOSKI: Right. h 2 MR. WIGGINS: 'I' don't know if we'have asked the 3 Westinghouse question. But,.they are certainly part of the 4 answer for drawing this out. It-is buried'in the fact that i -i 5 the recirc ratios are so low. ? 6 MR. CARROLL: Is my impression correct that - l t s 7 Westinghouse steam generators do not experience film boiling 8 at full load? 9 MR. CATTON: I don't think anybody plans on film 10 boiling in something like this. 11 MR. KARWOSKI: Certainly Westinghouse -- 12 MR. CATTON: You don't want it. ) 13 MR. KARWOSKI: -- has not had this experience.. 14 MR. CARROLL: I know that. 9' 15 MR. LINDBLAD: Could you show us again that slide j p 16 of the elevation of the steam generator? 17 MR. CARROLL: Film boiling is really going to get i 18 you in trouble. [ t t 19 MR. CATTON: That's right. 1 i 20 MR.. LINDBLAD: Where is the top of the bundle l f 21 compared to water level? 1 ] 22 MR. CARROLL: I am surprised at -- { 1 23 MR. SHACK: You see that the utility's thermal i d I 24 hydraulics -- CE didn't design this thing to have film j ) 25 boiling, did they? l 4 i 1 i ANN RILEY & ASSOCIATES, LTD. l Court Reporters { 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 j (202) 293-3950 1 4

[ i .326 eF-1 MR. CATTON: The thermal hydraulics of a steam 2 generator are pretty. flaky, frankly. I 3 MR. LINDELAD: There is the top'of the tube, l 4 compared to the water level? I 5 MR. CATTON: You can see the scalloped thing l' 6 across it. 7 MR. LINDBLAD: How much submergence on the tube? ] l' 8 I don't see it. ) 9 MR. KARWOSKI: Well, there is a transition. 10 MR LINDBLAD: Oh, I see it now. Yes. Okay. 5 11 MR. KARWOSKI: I think this was -- but, I mean, i 1 i 12 there is a transition -- J 13 MR. CATTON: It's probably about

eet.

i l 14 MR. KARWOSKI: -- to boiling, so ..;r level i. l 15 MR. WIGGINS: What is the water level inside the in the steam generator is kind of an academic question. 16 area 17 You only measure the stuff in the annulus. So, the drawing i l 18 up there is a bit artificial I would think anyhow. In any 19 steam generator, you know, when you talk about level and l l 20-steam generator, there are always annulus measurements. It i l 21 is kind of an engineering argument what really is happening i i 22 inside the bundle I would think. I think it is fair to i 23-assume in any generator that there is something going on 24 that is forming steam. So, what you at least have is an I. L 25 increasing steam quality or reducing moisture. I l ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 ( 2 0.2 ) 293-3950

..m.. 327 1 MR. LINDBLAD: Or, it might be a dryer un there. i 2 MR. CATTON: So, are they going to increase the-3 recirculation ratio, or at this point they don't know? 4 MR. CARROLL: Or can they? [ 5 MR. KARWOSKI: We have asked them t' hat. Right-6 now, they -- as I wi'l get into shortly -- they'have reduced 7 power level primarily to approximately 85 percent, in order. 8 to reduce the potential for dry-out in that region. 9 MR. CATTON: How do they know that that's enough?. l 10 MR.. KARWOSKI: Well -- ] 11 MR. WIGGINS: My understanding is they also reduce .. j 12 power even more than that to allow for a flushing to occur. f 13 MR. CATTON: I didn't understand. Could you 14 repeat that? i f 15 MR. WIGGINS: I also understand that monthly they l 16 also reduce power, I believe it is down to 20 percent, in 17 order to allow for a flushing in that upper area. j 18 MR. KARWOSKI: The licensee does periodic down l 19 powers in order to get the contaminants out of the crevices j i 20 and to clean them up with their blowdown systems. l 21 MR. CATTON: So, with all of these agonies, he 22 wants to fix it too? 23 MR. KARWOSKI: Most definitely. Most definitely. 24 MR. CATTON: Yes. But, if you are doing it { 25 at cycle like that, it is probably a big headache for the r J ANN RILEY & ASSOCIATES, LTD. Court Reporters-1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 i 4 l

o '] 328 1 operations. I.would be very interested in seeing the ~ 2 thermal hydraulic analysis. Would that be possible? .It has-3 been somewhat of a disappointment. I would be interesting 4 to see how well CE does it. 5 MR. CARROLL: Does the staff have CE's thermal 6 hydraulic analysis? P 7 MR. KARWOSKI: We have not received their detailed 'i 8 thermal hydraulic analysis. -t 9 MR. CATTON: Well, are you going to? j 10 MR. KARWOSKI: At this point -- well, I think it 11 is important to realize what the licensee used it.for. They i 11 2 primarily used it for identifying an area of interest. They 13 did not qualitatively or quantitatively use that analysis in i 14 any means. It was more of a qualitative analysis indicating 15 that the upper portion of the tube bundle was susceptible.to i 16 contaminant concentration. r 17 MR. CATTON: How far away are they from fluid [ 18 elastic instability? 19 MR. KARWOSKI: I couldn't -- i i 20 MR. CATTON: You remember what happened to one l 1 21 other steam generator when they increased the recirculation I 22 ratio? ~ 23 MR. KARWOSKI: Right. The licensee has not 24 changed the circulation ratio. We asked them that -- to 25 address that -- whether or not it would be feasible to l l ANN RILEY & ASSOCIATES, LTD. Court Reporters i 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 l

,~. .~. - 329 j i 1 change that and what advantages there will be. ] ] 2 MR. CARROLL: Can he change the recirc ratio? 3 MR. KARWOSKI: I believe they would have to j 4 4 actually go inside the steam generators and make material i 5 modifications in order to do that. So, whether or not that l a 6 would be feasible -- l i 7 MR. CATTON: They changed the baffles up at the a 8 top and do a few other things. t 9 MR. CARROLL: Well, some are easier to do than f i 10 others. t 11 MR. JONES: This is Bob. Jones of NRR. Ivan, we l 12 will get you what we have on the analysis. I am not sure we l 13 have a lot of the details. It is -- the AFOS code is what l 14 they are using to do the calculations. I am not sure we i 15 have the details.

l 16 MR. CATTON:

That's the EPRI code. 17 MR. JONES: Right. It's the EPRI code. l 18 MR. CATTON: It's the one that EPRI says -- told 19 me I couldn't have because it is not used in the licensing 20 arena. J l 21 MR. JONES: Right. l 22 MR. CATTON: Of course, that is none of my I 23 business. 1 24 MR. JONES: And it is still not used in the 2 25 licensing arena. And, in all honesty, we have not focused 1 ANN RILEY & ASSOCIATES, LTD. l Court Reporters l 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 L

'330~ 1 on the review of the specifics of the code. We were also 2 looking at a very short timeframe in trying to make 3 decisions here. And that kind of a review will-be fairly 4 extensive. We looked at it as providing insights as to the 5 general behavior of the' steam generator, recognizing j! 6 potential limitations of such a complicated code and ) ~ as confirmation l 7 behavior in the steam generator, and then, 8 of the MRPC indications in defining the inspection scope. 9 C', we kind of concentrated at that end. 10 We think their arguments are generally plausible, 11 but the exactness of the calculation we don't want to get ] i 12 into a lot of arguments on that. So, we have not j l' 13 concentrated on the review. l 14 MR. CATTON: I am interested in fluid-driven { l 15 instabilities. h t 16 MR. JONES: Right. We would be glad to give you j t 17 what we have. 18 MR. CATTON: Okay. Thank you. 19 MR. CARROLL: Now, although I have been away from 4 l 20 it for a while, I guess I keep hearing rumblings that people 21 are rethinking steam generator chemistry to some degree -- l ) 22 that we are -- or feedwater chemistry, and we keep inventing l 4 23 new limits and forcing the levels of contaminants down and i 24 down and down. I guess some people have argued that we t 25 don't really know what ratios of different chemical species ANN RILEY & ASSOCIATES, LTD. Court Reporters l 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 [ (202) 293-3950 . ~.

-.m.. L V l 331 1 are.-- how this is impacting the ratio of chemical species. 2 When you dry out, even though you'may have less impurities [ 3 in the water, you may have a very aggressive attack on l 4 tubes. 1 l 5 Has that. sort of thing -- has.the thought that y 6 that sort of thing played a role in this? i 7 MR. KARWOSKI: Yes. The licensee did look at that 8 and has instituted a multiratio control as a result, so the l 9 licensee is looking into that, i 10 MR. CARROLL: Those were the words I was looking - i 11 for -- multiratio control. Okay. l l 12 MR. KARWOSKI: As Bob Jones and Jim Wiggins 13 alluded to, the licensee performed a Reg Guide 1.121- ] 4 14 analysis to determine the appropriate operating interval for j ] 1 15 this next upcoming inspection. As a result of their -t 16 analysis, they determined that a six-month operating i 17 interval was acceptable. However, based on the staff's j i I 18 review, there are a lot of uncertainties in this type of 1 19 analysis. J l 20 You have to determine when the crack begins to 1 I i 21 initiate, at what depth it was in length at the beginning of { 22 cycle. And, due to some of these uncertainties, the staff i 23 could not conclude that all tubes will meet the regulatory j 24 guide criteria at the end of six months. However, the staff ) i 25 did conclude that operation for six months was acceptable, l 4 I a ANN RILEY & ASSOCIATES, LTD. i Court Reporters 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 (202) 293-3950 P ,--,,n,. ,,_.-.3 ,,,,,y.,. p.,mm_.,3, m, .. 9 7 .,.p. m. .e .,,, ~.,.. - -.,...v,---- ,m-.

I 332 1 based primarily on the risk associated with operating _with-2 potentially degraded tubes, and also due to other licensee j t 3 actions that they performed. I 4 These other actions include improved _ primary to 5 secondary leakage monitoring capabilities, including the 6 adoption of primary to secondary leak rate or lower primary f 7 to secondary leak rate limits. In addition, they improved 8 their EOPs, as Dennis Kirsch mentioned briefly this morning. 9 Also, in order to reduce the potential offsite 10 dose consequences of a steam generator tube rupture, they t 11 reduced their variable over-power trip set point, and 12 coolant iodine activity levels. In addition, they have 13 incorporated the lessons learned into their simulator, and s 14 have trained the operators appropriately. i 15 MR. WIGGINS: Just let me clarify one point on 16 whether or not it meets the Reg Guide 1.121 for the six l t 17 months. The staff is not expecting a tube rupture to occur j 18 in Unit 2 in the next six months. That is one of the things 19 that is articulated in the -- in our safety-evaluation 20 report. It is more or less the leakage performance of the 21 tubes under the design basis accidents that we can't 22 conclude from the materials point of view that the -- we I 23 can't. agree with the licensee that, from a materials point l l 24 of view, they will be able to show the Reg Guide 1.121 l i 25 margins. i i I ANN RILEY & ASSOCIATES, LTD. Court Reporters j 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 l (202) 293-3950 l 1 I

.-.~.. ~ I i 333 1 Basically, the SER, if it is -- if you read it I 2 completely, shows that the staff's agreement'with the i 3 licensee 6-month operating cycle is based on a. systems. { 1 4 assessment, leak detection, EOP coping strategies. But, we l'i 5 5 are not expecting a tube rupture. We certainly wouldn't-g j _ 6 agree to a restart if that were something we thought was- { 7 reasonably expected. l l. 8 MR. LINDBLAD: Do we have any information on the j 9 pressure drop to the steam separators at full load? 10 MR. KARWOSKI: Excuse me? 11 MR. LINDBLAD: Do we have any inform.cton on the j 12 pressure drop through the steam separators at full load? l 1 13 MR. KARWOSKI: I don't have that information with. i I 14 me. j 15 MR. LINDBLAD: Are the steam separators operating j 16-more efficiently than designed? i 17 MR. KARWOSKI: I couldn't answer that. I don't } 18 know if they have done any testing on that. I i 19 MR. SEALE: It strikes me that we have got a 20 possible example of the downside of plant standardization i j 21 here. Have the other two units exhibited similar leak i 22 rates? 1 l 23 MR. KARWOSKI: The other two units -- well, let me 24 start -- Unit 1 is currently shutdown and performing an 25 inspection. As of yesterday, they had not identified or -- 5 j ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D..C. 20006 i (202) 293-3950 l 1 -c.---- -.nn

1 i 334 1 l 1 I should say',' have not confirmed any freespan' axial crackc-1 ~2 in Unit 1. 3 MR. SEALE: No. I meant any leaking-of-the sort 4 that you had prior to the tube rupture -- the iodine 5 indications and so on. l 1 1 6 MR. KARWOSKI: There have been some minor' primary .) l. I 7 and secondary leakage in the other units; however, once I i 8 again, in Unit 1 they have not identified any indications. ] 9 In Unit 3 right now they have like a half a gallon per day i i l 10 leakage. 8 I ( II MR. SEALE: And : understand 3 is -- both 2 and 3 12 have backed off to 85 percent power? 3 ( I i 13 MR. KARWOSKI: That is correct. 1 L 14 MR. SEALE: And Unit 1 may or may not? j 4 J 15 MR. KARWOSKI: That's correct. Right. The [ 4 16 licensee has done this on his own to extend steam generator l i j 17. life. l 18 MR. CARROLL: Now, how about San Onofre? Does it j l t 19 have the same steam generator design? -j i 20 MR. KARWOSKI: No. San Onofre,.is a different' ] 3 21. design. I believe San Onofre 2 just recently completed an i 1 22 inspection and did not notice any indications in that j. 23 portion. 24 MR. CARROLL: So, are these steam generators 25 anyplace other than Palo Verde? Are they in Korea? l ) ANN RILEY & ASSOCIATES, LTD. f Court Reporters 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 j (202) 293-3950 i -i

E 335 { 1 MR. KARWOSKI: No. Just the three -- oh, yes, I i l 2 am not sure -- there is a plant in Korea I believe that has 3 System 80 steam generators. I don't believe it is f -l 4 operational at this time. .j i 5 MR. CARROLL: I guess we know that. -l 6 MR. SEALE: 80 or 80-Plus? I mean,.there are some l 7 differences I understand -- 8 MR. KARWOSKI: There are some -- l i 9 MR. SEALE: -- in the steam generators. l 10 MR. KARWOSKI: Right. There are some differences, 11 but I couldn't elaborate on-them. l 12 MR. CARROLL: The plant our recently departed' l 13 senior fellow, Stu Long, is at now in Korea is the one we ] 14 are talking about. 9 15 MR. KARWOSKI: Yes. The System 80. f I 16 MR. CARROLL: It's an 80, the two units that he is t 17 associated with.

j 18 Peter?

j 19 MR. DAVIS: I have a question. First, I would j 20 like to compliment you on an excellent presentation. Was 21 there any indication that this failure could have l 4 22 compromised adjacent tubes by impact or any other type of 23 mechanical problem? We are concerned about multiple steam l 24 generator tube ruptures, of course, and just wondering if-i L 25 you looked for any interaction potential or saw anything? h ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

-. _. _ _. ~. - - + -. 1 336 .l ] 1 MR. KARWOSKI: To the best of my knowledge, there 2 was no interaction with other tubes. They did-inspect the 3 other tubes in that area -- you know, the adjacent tubes and !1 4 what not, and they didn't see any type of -- they haven't 5 reported any type of impact damage or anything. I l 6 MR. DAVIS: These tubes are very close together !j 7 and this opening, it seems to me, must have hit some 8 adjacent tubes. -i 9 MR. CARROLL: Yes. But, it was probably so big } 10 the velocity wasn't very high. l 11 MR. SEALE: Yes. I recall seeing a boroscope I 12 picture that Mr. Igne I guess got from someone back I would j u 1 13 say maybe May that was taken through the fishmouth. i 14 MR. KARWOSKI: That's right. i 15 MR. SEALE: And, at least to my uneducated eye, it I 16 didn't look like there was any damage adjacent. .I assume 17 there was a very careful examination of that picture and. j 18 similar kinds of things? { 19 MR. KARWOSKI: Right. I saw that videotape that 20 you are referring to. From my recollection, I don't 21 remember anything on an adjacent tube. And, of course, they t 22 did inspect that with eddy current probes, both the bobbin 23 and MRPC. 24 MR. SEALE: Okay. j 25 MR. SHACK: You mentioned the inspection of Unit 4 l ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

i 337 1 1. Now, they are not seeing any axial indications. Are 2 they doing the video inspection looking for the deposits? 3 MR. KARWOSKI: For Unit 2 they were able to do 4 video inspections because they removed eight tubes. So, 5 what they were doing was taking the video probe into that 6 tube slot, and then they could inspect'the adjacent tubes 7 around that. So, they currently do not plan, to the best of-8 my knowledge, of performing those inspections. 9 MR. SHACK: But, they are doing the rotating 10 pancoil inspections in Unit 1 in the arc? 11 MR. KARWOSKI: Yes. Well,.they are doing a more 12 limited inspection. Most of the indications were primarily 13 found here, here, and here. So, what they are doing for 14 Unit I right now is MRPC in a more limited arc,-to see if 15 they have a problem. If they identify a problem in that 16 limited arc, then, of course, they would investigate whether 17 or not expansion was necessary. So, their arc essentially 11 8 is more cut off and is more limited. 19 MR. WIGGINS: It may be worth while, Ken, to go i 20 over a bit of where the staff comes out on the utility of 21 the Unit 1 inspections. As I said, we agreed to a six- -l 22 month operating cycle for Unit 2, and we agreed to it 23 largely on a systems basis; but there was something in our 24 minds when we agreed. We recognized that Unit I would 25 quickly come down and we would be able in a reasonable time ANN RILEY & ASSOCIATES, LTD Court Reporters 1612 K Street, N-W., Suite 300 Washington, D.C. 20006 (202) 293-3950

(l 1 1 338 1 1 J l' period to get more.information on'what.is really going on in '2' the 3 Unit's steam generater, based on the Unit 1 exam. 3 The reason we are concerned about it is, if you t I 4 remember the Unit 3 is in fact operating. The licensee is j 5 going back over data done on the last exam, which was 6 October92 on Unit 3, and they are looking more carefully l 3 1 7 at the Unit 3 exams, recognizing though that the techniques 8 used for the Unit 3 exams at the time were different, NDE 9 technique I guess, and that kind of NDE they were doing was 10 different. So, they are trying to make some calls on Unit 3 l 11 using 20/20 hindsight based on what happened on Unit 1. l 12 That is difficult. ~ 13 They are finding things. They are finding that 14 there are at least two indications in Unit 3 that have been i 15 identified that the licensee had told us about and'the j 16 licensee had to deal with. It wouldn't be unreasonable to 17 expect that they would find more as they complete the data j 18 review. 1 19 The staff has a confirmatory action letter in l u 20 . place that essentially the licensee has committed to keep is i ) 1 21 apprised of what is happening both in Unit 1 and what is j i 22 happening in Unit 3. So, we will have to continue to see 23 where that leads us. 24 It might be appropriate to go on to more general L 25 where we go from here on steam generators, if you are ready q l ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 ] (202) 293-3950 j j

.1 s 339 1 and want to. If you have'any'more specifics on Palo Verde-l 2 we can do that. i 3 MR. CARROLL: Shack has one more question. 4 MR. SHACK: Is the wear problem generic to all 5 three units also? l 6 MR. KARWOSKI: Yes. They have experienced wear in' 7 primarily the upper egg crates at the vertical straps, the i 8 bat wings and -- f 9 MR. WIGGINS: And that is not uncommon with CE 10 either? There have been wear at bat wings and. straps in 11 other units. I think that is a common thing that CE look. 12 for. 13 MR. CARROLL: San Onofre has had a lot of problems i 14 with that. f l 15 MR. WIGGINS: It is something that CE plants look l 16 for. We don't think the wear is -- it is just something. I 17 We don't think it contributed to this event.. ? i 18 MR. SHACK: No. I just -- just as sort of a i 19 collection of generic steam generator problems. I 20 MR. WIGGINS: There is a collection of all kinds 21 of problems. Yes. That's true. 22 MR. SHACK: Yes. 23 MR. WIGGINS: All right. That is a good entry 24 point when we talk about a collection of a number of 25 problems in steam generators that go into where are we going ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

_.. _ ~. _ _ _ _ _.. -__._..__..q 340 1 from here. a. h. 2' Pretty much we have discussed Palo Verde'and what' 3 we are going in specific with Palo Verde. As I said, we are 4 keeping -- the licensee is also given some credit also. 5 They'are paying a lot of attention to the results of Unit 1. I 6 We are paying a lot of attention to what is going on in Unit t 7 3. .The licensee has committed to us to have Unit 3 down in l l 8 the mid to late November timeframe to investigate some of I j 2-9 these indications they are picking up out of the data l I 10 review. 11 The one that is the most interesting is they 1 ) 12 detected an indication, whose length is about the length of l 13 the one that had a difficult here. It was about an 8-inch i i 14 indication of something going on in Unit 3. The licensee's I 15 best estimate is that that is not going to be a problem 16 between now and when they shutdown. 17 Now, that gets you to the point where you have to 18 consider the importance of online detection. Let me start a j i l 19 little bit more basically on where we are going on steam L i 20 generatore. And I believe you will get a more thorough 21 discussion of this in the future. 22 As you probably know, it starts back several years l 23 ago, in the Trojan case and with Farley. The industry has 24 approached us with a request to change our steam generator 25 tube repair criteria. I think the staff is amenable to ANN RILEY & ASSOCIATES, LTD. Court Reporters i 1612 K Street, N.W., Suite 300 Washington., D.C. 20006 (202) 293-3950

---~ 341. I consideration of change because we recognize that the steam I 2 generator program that is articulated in the current tech 3 specs doesn't really match what is going on. The tech spec l 4 criteria are looking for randomly generated wall _ loss ') 5 problems. That is why you see fairly low percent sample 5 6 inspection plans. That is why you see 40 percent through-y j' 7 wall dimension for repair criteria. That really comes from 4 1 8 a wall loss estimation -- a uniform wall loss cnr wall .i L 2 9 thinning. That isn't what is going on in the generators-l l i 10 these days. They are cracking, not wall loss. Cracks j i 4 11 behave different than uniform thinning, i i 12 As I said, both Trojan and Farley approached us i i i j 13 for a voltage-based criteria using bobbin coil, to.look at a l 14 particular type of defect than outside diameter stress i 15 corrosion cracking situation, coupled with inner-granule I 16 tack and the tube support plate intersections. And several i 17' years ago, we -- a couple of years ago, we started focusing-j 18 on that. In fact, we did issue repair criteria or agreed to l j 19 repair criteria for that particular type of defect. That i 20 got us to thinking maybe this is telling us something. 1 i 21 Maybe the right way to approach steam generators is to look l 22 at what we would call a defect-specific repair criteria, and j 23 our thinking evolved into an overall steam generator 24 degradation management program -- a degradation-specific G j 25 management program, which is beyond just inspection and l l l ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 j Washington, D.C. 20006 (202) 293-3950 i i ........__.._..,..m.,_.,,-.,__...._....,__.,._,,~,.m...

'h 1 F i 342 i 1 repair. 2' So, where we went is we formed a task force to 8 i 3 look at what we were doing in the Trojan and the Farley and' l I i 4 several other cases. We had these'similar interim repair. 5 criteria out there in several plants. The task force was to l, i 6 look at how the staff had conducted its activities and where. l 7 it should go. Also, we had some internal disagreements we i p l 'l 8 needed to reconcile with regard to where we were going. We \\ 1 9 thought that this would be an opportunity to do that also. j 10 The team got together. It was a consolidated i 11 effort between NRR and Research. The team put together a i 12 draft NUREG, it's NUREG 1477, and placed it out and sent it j 13 out for public comment. NUREG 1477 deals with the Trojan l l I 14 and Farley-specific situation, the ODSCC at the tube support ? 15 plate. i

i 4

16 That NUREG looks at things like the. leak j J f 17 detection, the appropriate way to calculate leak rates. It i 18 looks at what the ISI ought to be in terms of inspection l 19 scope and nondestructive examination methods; what are the j 20 repair criteria and what are the accident implications of 21 those repair criteria, particularly, what happens in a main 1 22 steam line break; what kind of radiological assessment i 23 should you be doing, realistic, versus design basis. j 24 That NUREG was out and issued. We have gotten the l 'l ^ 25 public comments. We need the disposition. That is what we s i ^i i ANN RILEY & ASSOCIATES, LTD. Court Reporters 4 1612 K Street, N.W., Suite 300 I Wa'shington, D.C. 20006 (202) 293-3950 I

j 343 i i 1 are up to at this point. The intent would be to disposition j-2 the public comments, finalize the NUREG and issue some i 3 generic communication, whether it is a topical or a generic 4 letter that makes that NUREG implementable at plants with j 5 that type of a problem.. v. l 6 Now, we want to go beyond that. We know that j 7 there are other types of defect-specific mechanisms that are i f i 8 out and can be taken advantage of. There is primary water } ) i i 9 stress corrosion cracking in the tube transitions in the 10 wall transition areas. We have that problem. And the ] 11 overseas have that problem all over. They have a lot of 4 12 that overseas. We know that there is some room for looking 1 1 13 at these defect-specific mechanisms and coming up with a [ 14 more appropriate repair criteria. l 15 We have been working with EPRI. They have a steam l l l l 16 generator group that has been looking at the APC issue, l i l 17 mostly centered on the Trojan /Farley-type of scenario. And 18 they have delivered four reports to us: An overview report 19 of how you would go about a defect-specific management i { 20 program; some ISI guidelines; NDE qualifications; and the l 21 axial repair criteria for that mechanism. f 22 But, the staff wants to go one step further than t i i t j 23 that. We are reviewing the EPRI documents, and we intend to j i 1 24 come to some reasonable closure of it. I believe it is 4 going to be an interim closure on those issues, because the j 25 i i i I I ANN RILEY & ASSOCIATES, LTD. l Court Reporters 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 (202) 293-3950 j l a l- ~

-i i 344 l l 1 next step is rulemaking. We decided that we needed to put' -l 2 some rigor to the process, and we need to do that for a i 3 rulemaking activity. I 4 We are looking at developing a performance-based ii l 5 rule that would include in it, from a steam generator-point c ? 6 of view, things that are a part of this whole picture. What t 7 is the right inspection? What is the right NDE to use? 8 Let's'not get married to eddy current Maybe there are 9 other technologies. Let's not write a rule that bliminates 1 10 other technologies from use. But, we can write a rule that j l 11 says whatever you do, it has to achieve certain targets. 12 Leak rate detection. We think that, if a licensee i 13 is going to be able to deal with these type of mechanisms, 14 they are going to have to go to a more -- to some type of j 15 online detection mechanism. The rule would allow credit to t ~ i 16 be taken for licensees that do that, and it will allow 17 negative credit for licensees who elect to not do that, f 18 We will look at repair criteria that'are matched 4 19 at a specific type of defect. We will look then at the 20 accident dose and the risk associated with that criteria. 21 We would look at the uncertainties in each of those items i 22 that I just discussed. What we would do then it seems, as i j 23 we foresee it, hopefully, is you would have a number of i 24 factors that affect overall risk for steam generators with 25 defects in them. If a licensee were able to -- or as i i f i ANN RILEY & ASSOCIATES, LTD. j i Court Reporters i 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 l (202) 293-3950 i .~

345 1-disposed to look at one of those factors, let's say in-i service inspection, and do a better in-service inspection, 2 3 in other words, increase scope, or look at NDE and do a l i 4 better NDE, do better qualification mechanisms, what will l { 5 happen is the uncertainty of what is not found will reduce' f 6 and the licensee will be able to take the advantage of that .l 7 uncertainty. It would manifest itself in a more relaxed I 8 repair criteria. l 9 The licensee would be able to invoke operating j 10 strategies -- let's say lower gallons per the leak rate. ) t 11 allowed in operation, more reliable detection. It would be l 12 able to look at a lower RCS iodine concentration, a lower l i 13 fission product concentration in the coolant, and take j 14 advantage of that tighter operating strategy to relax the-15 repair criteria. l -l 16 What we were hoping to do through all of this is 1 L 17 to give the industry some incentive to do a better and more .[ t 18 thorough inspections, to do them smarter, to use the bet NDE f i 19 available, and to adopt good leak detection and monitoring { 1 20 strategies and to consider the overall effect of what they 21 are doing on risk, and possibly come up with a repair l l 22 criteria that is not only more realistic to the situation 23 that exists. 24 But I guess one could say it would be -- you can i 25 make an argument that it is less conservative, but I don't 4 I ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 i

E v 346 .1 think that's the right argument. Yes, maybe the repair' 2 criteria in and of itself is less' conservative, but, if you 3 .look at the full scope of what is going on, it is a-better - 4 - from an engineering point of view, it is a better way of 5 approaching this thing. The. staff has a -- that.is a big-6 chunk of work. l 7 We think that -- we would hope that in a couple of l l 8 years, 1995 or so that this rule would be completed and will- 'I q 9 be out there. That would allow us to.try to deal with.these t 10 problems, because, quite frankly, we don't see any signs 11 that these steam generator issues are going to go away. l 12 What has nappened is there has just been more and different } 3-l- 13 things happening. People have tried, and the industry has } i 14 tried everything from chemistry to operations, whatever. It i 15 doesn't seem to help. So, we are going to use this rule to f \\ j-16 try to at least provide some sanity to what the staff is j I I 17 doing in this regard. t 18 MR. CARROLL: Did I understand you correctly that I j 19 you are going to deal with the voltage -- .i 20 MR. WIGGINS: Yes. i 4 21 MR. CARROLL: -- plugging criteria soon? j 22 MR. WIGGINS: Soon, yes. l i 23 MR. CARROLL: What have you committed? 24 MR. WIGGINS: What we have agreed to the industry I 25 is -- and a little of this is pragmatism. You know, that is t ANN RILEY & ASSOCIATES, LTD. [ i Court Reporters i ~ 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 (202) 293-3950 j

F 347 4 1, 1 a problem that exists right now. A little bit is probably 2 regulatory fairness. We initially started off focusing on 3 this ODSCC problem. We were going in a particular i I 4 direction, which was a tech spec change. And basically the l r I h 5 staff elected to expand it. We told the industry we will

l 6

review these documents and we will come out with -- l 7 hopefully, if they did their job right and we can agree -- l i l 8 we will come out with something that could be adoptable in 9 the interim -- the interim being between the time where we l 10 finisn the act on those reports, and the time that we do the I 21 rulemaking activity. l d } 12 MR. CARROLL: I recently read a Bill Russell trip l l l 13 rep:rt, wbrze he had been in Europe, and this had to do with l 14 what EDI was telling him about their experience. l l 15 MR. WIGGINS: Yes. 1 l 16 MR. CARROLL: I found it very interesting. 17 MR. WIGCINS: Yes. EDF has in the recent past the I i-18 accumulated experience of hydroing about 60 steam generators 19 at a Delta-P that looks like main steam line break Delta-P. l l 20 These generators have various defects in them, the outside ) 4 1 i 21 diameter stress corrosion cracking at the two support l l 22 plates, the primary water stress corrosion cracking at the 23 roll transition areas. The leak rates come out quite low-. j l l 24 It is a very interesting set of data, and we need l l l 25 to get pretty smart in what that data really means and how i I ? 1 i l ANN RILEY & ASSOCIATES, LTD. Court Reporters l 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 i (202) 293-3950 L

348 f 1 .it was developed. Ken Karwoski and Jack Strosnider, the 2 Branch Chief, they have a trip over -- EDF has invited us to 3 come over and given us the opportunity to look in detail at 4 their data and ask them some detailed question about it. j 5 And Ken and Jack intend to go over there in the early part I 6 of November at this point in order to see whether it is -- j 7 whether it can be taken into consideration here, t i 8 MR. CARROLL: Okay. We are running over. 9 Have you got one more question, Bill? ~j 10 MR. LINDBLAD: Yes. I admire your program. It t 11 sounds like a very good approach. But, isn't it true that, 12 as you are trying to feel your way to the limits here, you 13 will only know when you come too close to the limits with .{ i-14 having a tube rupture occasionally in one of the units? i 15 What is the incidence rate of tube ruptures on steam f 16 generators worldwide per year? 7 f 17 MR. WIGGINS: Maybe Bob 'ones can answer that. 18 MR. JONES: I think we have some stateside 19 national statistics. I 20 MR. LINDBLAD: Well, what is the stateside then? 21 MR. JONES: I thin works out.to be about 10 to j i 22 the minus 2 pGr reactor year h&s been the frequency. i i 23 MR. CARROLL: Okay. We better wrap it up if we i 24 are going to keep on schedule. -l 25 I did want to give Palo Verde a chance to say j l l I l i ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 [ (202) 293-3950 l 1 l' l l l-. ~.

i 349 1 something if they wanted to. l 2 MR. BERNIER: I think, overall, the presentation 'i 3 is a fair presentation of the event, and the actions that 4 were taken by Palo Verde to try to correct the problems with 5 the steam generators. We are still working at it. 6 Do you have any particular questions? 1 7 MR. CARROLL: I don't believe so. I f 8 Okay. I would like-to thank the presenters. I l i i 9 thought it was an excellent presentation. Very informative. l ) I 10 MR. DAVIS: Yes. Very good. 11 MR. CARROLL: Very well done. j 12 MR. LINDBLAD: And, for the Palo Verde people for j I j 13 joining us this morning. l j 14 MR. CARROLL: Yes, indeed. .I i 15 MR. WILKINS: We will take a 15-minute break, and i I l 16 resume shortly before 10:45. We are running a little behind l i t 17 schedule. j j I 18 [ Recess.] l I l 19 MR. WILKINS: Let's reconvene this morning I 1 i i l 20 session. 21 The next item on the agenda is the discussion of l 22 some proposed final amendments to 10 CFR Part 55. I will 23 turn the meeting over to the Subcommittee Chairman, Jay 1 l 24 Carroll. ] I i [ 25 MR. CARROLL: Okay. Let's see. Have you passed f I i i t ANN RILEY & ASSOCIATES, LTD. Court Reporters i 1612 K Street, N.W., Suite 300 j Washington, D.C. 20006 l-(202) 293-3950 I I b,-.. ~., ~,.. _ -, _ _, - -... _ _ _.., _.. _..., _ _ _. _... _. _. - -._......_.......,.-_,.____,_,._-.m

h 350 I 1 out the handouts? 2 MR. ALDERMAN: Yes. l 3 MR. CARROLL: I have got too much paper in front l 4 of me. - i 5 MR. WILKINS: The recorder doesn't have it. l 6 MR. CARROLL: Okay. Well, we heard about this '7 about a year ago when these proposed amendments on-recall 8 exams were about to go cut for public comment. We'said in 9 our letter -- we endorsed the changes that were being i 10 proposed at that time and did want to hear back from the 11 staff after they had evaluated the public comments and were i 12 in the process of putting out the final rules. So,. that's i 13 where we are today. 14 MR. BAHADUR: Thank you, Mr. Chairman. I am Sher f 'i 15 Bahadur from the Office of Research. And what I plan to do 16 is have a combined presentation of the Part 55 final 17 amendments. With me is Bob Gallo, the Branch Chief of the 18 opera'.ing Licensing Branch from the Office of NRR. i 19 MR. CARROLL: Sher, just a moment. I should have i i 20 pointed out to you that in this package the slides are the j 21 last part of the package that Sher is talking from. l l 22 Go ahead. i l 23 MR. BAHADUR: Before I walk you through the l I i 24 slides, Mr. Chairman, I would like to thank the Committee 25 for agreeing to review this, part of a review which is going i ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C 20006 (202) 293-3950 i l m, a. ---n, .~.---~-.....-.---.--.n,--,-n.,-nn~-, .~--~,nr

_.~. I 4> 1 351 1 on by various offices of this package. 4 i 2 To this date the division concurrence from j 3 Research and NRR has been received. The package is right l ~ 4 now under review from ODC, NRR Office, as well as the l ] 5 Research Office. And we anticipate that in a week to 10 l t 6 days' time, we will receive their concurrences as well. I i 7 plan to go to CRGR in the first week in November. And I t 8 will come to that when I come to these schedule slides. i 9 As you mentioned, we were in front of the l 1 l Committee last year about this time. At that time we l 10 l 11 presented the proposed amendment to the Committee. You 12 observed the Committee said it was okay for us to have a f ] 4 13 published rule. We did publish the rule in May of 1993, 14 with a comment period that expired recently, and we received 15 42 comments. What I would like to do is to summarize those 16 comments for you, give you a presentation as to how we l 17 resolve that, and then Bob Gallo will give a presentation on j 2 j la the inspection program which ib very important for the t 19 success of these amendments. l f I 20 The first amendment, if you recall, was to delete 1 21 the requirement that NRC should administer a comprehensive 1 22 written exam and a written test for any qualification h 23 condition. We received 42 comments. 36 of those 42 I i 24 comments favored that we delete this requirement. Most of I i 25 the comments car.e from power reactor licensees. 13 were I ] ANN RILEY & ASSOCIATES, LTD. Court Reporters l 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 i

I 352 l 1 from the non-power reactor licensees. One came from the i 2 National Organization of Test, Research and Training i 3 Reactors. l 4 Their basis of agreeing to this and supporting j 5 this deletion was that, first of'all, it will reduce the 6 regulatory burden and, secondly, it will also improve the i 7 operational safety at the facilities. 8 Six comments were in opposition to this amendment. 9 The comments came from the public group. Comments also came i 10 from the State of Vermont and the State of Illinois. A i' 11 state nuclear engineer from the State of Vermont said that 12 they were in opposition of this comment because there was no ] 13 confidence in a licensee's program that they -- the licensee i 14 would be able to detect an unsatisfactory program. That was l 15 one of the basis why they opposed this particular deletion. 16 Also, the State of Illinois mentioned that the current I 17 requirements provide some sort of an incentive for a i i 18 facility to have their programs to the level of acceptance t 19 by the NRC. I 20 MR. WILKINS: May I ask a couple of questions in i 21 this area? Does the NRC reserve the right to look at the ] 22 licensees' examination procedures and exams and so on and l 23 judge whether they are likely to be natisfactory? 24 MR. BAHADUR: Yes. As a matter of fact, that is 25 our proposed amendment number two, and I will'come to that. j h-ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 j

1 353 i 1 MR. WILKINS: I thought my answer was yes. 2 MR. BAHADUR: Yes. l i I 3 MR. WILKINS: And doesn't that address the Vermont l. 4 and Illinois issue? l 5 MR. BAHADUR: To some extent it does. The fine l l I-6 line was between inspection and overseeing a program, versus ~j i 'i i 7 actually conducting and administering an examination. And i 8 that was the point that Vermont was trying to make. i i 9 MR. WILKINS: The second question is does the law i 10 permit the states to administer their.own programs if the j I [ 11 NRC does not? i 12 MR. BAHADUR: Whether the law permits or the law I l l 13 requires, it could be two different things. l I i 14 MR. WILKINS: I asked " permit." l j 15 MR. BAHADUR: The way I understand it was that it i 16 was the National Policy Act which required NRC to come up l 9 t j 17 with the procedures to make sure that this process was in 1 1 l 18 place. And it was the NRC's response to that. requirement in j E 19 1987 when we came up with this-requirement that the NRC 20 conducts and administers the examinations as a i 21 requalification condition. 22 MR. SEALE: Would it be fair to characterize what _j 23 you are talking about then as an alteration from a v 24 performance-based evaluation to a process-based evaluation? } a 6 f 25 MR. BAHADUR: Mr. Gallo can answer that. l l i y v ANN RILEY & ASSOCIATES, LTD. I I Court Reporters 1612 K Street, N.W., Suite 300 'l l Washington, D.C. 20006 (202) 293-3950 'I s h s i

~ 354 1 MR. GALLO: One of the-things we want to focus on j 2 in the inspection program, which I have got a couple of 3 slides on later., is to have our examiners become inspectors o 4 who are going to observe the facility perform their annualL f 5 operating test. 6 MR. SEALE: Okay. l t 7 MR. GALLO: So, we still want to watch them do the 8 test, but we will not be doing our own full grading of each l l 9 individual. 10 MR. BAHADUR: One of the points I would like to 11 mention here is when we talked about adding these 12 requirements in 1987 and the NRC started conducting these ,i 13 examinations for the operators' license requalification, the 14 experience has indicated that actually NRC's staff were 15 duplicating the efforts which had already been done by most 16 facilities. Their tests, their examinations, their tasks - j 17 - we were asking just about the similar items which were 18 required to have been done by the facilities. And not only I 19 that. Our experience with these tests indicated.that the 20 pass rate have dramatically changed from low 80 percent to ] 21 almost like 90 percent with various operators -- 93 percent' ) i 22 So, it is with all of these experiences already in { i l 23 hand that the staff had gone to the Commission in 1991 to { 24 suggest that we should come up with a rulemaking to relieve i 25 these requirements. And it was extent that this experience i f r ANN RILEY & ASSOCIATES, LTD. Court Reporters I 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 l i

h 4 355 1 1 that'the. Commission had asked us to develop the rule. And' 2 when we came here last year we presented all of that to the-i 3 Committee. .{ 4 So, the resolution of'the comments, therefore, has 1 ~ 5 been that the staff has decided to delete that' requirement. .i i i 6 L 7 MR. CARROLL: Now, I am trying to.get things 8 straight in my own mind, in terms of chronology. .What you i' 4 l 9 presented to us last November or last October I mean, was a i 1 10 proposal to delete this requirement, except in cases where, 11 for cause, you felt it necessary to come in and administer' ) 4 12 your own examinations? j 1 F 13 MR. BAHADUR: That is very true. That was the l 14 proposed amendment. i 4 l 15 MR. CARROLL: And then, subsequent to that,'did i 't i 16 you not put a proposal together that would require some form i l 17 of examination every six years at each facility? .i 18 MR. BAHADUR: That was the earlier proposal, but } i' l 19 not in the proposed amendments. 20 MR. GALLO: That was part of the inspection { 21 program activities or whatever, that there would be a -- I i 22 think we said an annual inspection and a. periodic C I a 2. 23 requalification exam. We have since deleted the proposal to j 24 do the periodic requalification exams and we are sticking - 25 - the SRM came out on April 27th. e i ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 i Washington, D.C. 20006 (202) 293-3950 f

~ 356 1 MR. CARROLL: '93. 2 MR. GALLO: We are following directions from the 3 Commission. We deleted the portion of the program that had 4 a periodic examination in it. j 5 MR. CARROLL: Okay. But, I think we were led to 6 believe in October that there would be no period examination i 7 -- in October of '92. l 8 MR. GALLO: I looked at my slides from-last i 9 October and it was on there -- that we were doing t l 10 inspections and periodic examinations as well as for cause. e I 11 So, I think we had three parts to it, and now we have two. i 1 12 MR. CARROLL: Okay. I guess I would like to see 13 those slides, because -- l t 14 MR. GALLO: I think that is what was in the 15 Commission paper that went forward to the Commission. I am t i 16 pretty sure. l 17 MR. CARROLL: That's true. i 18 MR. GALLO: I think I have got the slides here. 19 MR. CARROLL: Okay. I would like to look at them. i 20 Go ahead. 21 MR. BAHADUR: The concern was whether the staff is l l still planning on doing the periodic inspections and the l 22 J 23 testing, as you mentioned? l t 24 MR. CARROLL: Yes. I guess in drafting the letter l j 25 I assumed that except for cause you guys were out of the ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

l 357 1 requalification exam business. 2 MR. BAHADUR: Which is very consistent-with the j 3 final amendments, which is -- i i 4 MR. CARROLL: Right. I 5 MR. BAHADUR: -- in front of the review you have. l 6 The second proposed amendment was we require NRC-7 licensees to submit their exam and test at least 30 days l 1 8 prior to their administration to NRC for review. 41 out of ) 9 42 respondents opposed this particular amendment. The point. l 10 was that this would be an additional burden on the NRC's j r-11 licensees, with no appreciable increase in the safety. 12 The comments suggested several alternatives. Some i 13 people suggested we should have a shorter lead time, not t l 14 really 30 days, but maybe a little shorter, or maybe we can l l 15 submit the exam after being administered, or that the j 16 examinations be available onsite for inspection and perhaps i r L l 17 a bank of several questions could be submitted to NRC for i 1 18 review at one time, and then the licensees could take the 19 questions from that bank. I 20 The reason why we have included this particular l f 21 amendment was that, if we have the exam given to NRC 30 days j 22 prior to administration, the staff would be able to review j l E 23 that exam, come up with the factors and criteria that they l l 24 may need during the onsite inspection However, when the i 25 pilot inspection programs were conducted, it was found that i ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 I (202) 293-3950 l

358 1 there was no really need for the NRC's staff to have these-il. 2 examinations in advance. l 3 And, therefore, in the final recommendations, you j l 4 would see the staff has resolved all of these comments by 5 adding a phrase in the proposed amendment.in its final form 6 where we say submit the examination and test upon request. l 7 By doing so, the staff is keeping an option open whereby.we l 8 can ask a licensee to submit the exam in connection with the i i 9 onsite inspection. If we find that the program is deficient 10 in any manner, we can go back and have the testing on cause, 11 not a routine testing, not a testing on a cyclic basis, but l i 12 only upon request and on cause. l 13 MR. WILKINS: That request would be after the exam i ? 14 had been administered usually? ] f 15 MR. BAHADUR: That's right. If there were -- for 1 ) 16 example, if there we.re -- situations came to light where we l l 17 believe that the program for a particular facility is 18 lacking in a certain manner, we could ask that facility to { 19 submit us the exam, so that we could examine that, review 20 that and see where the NRC staff has to go and do a j 21 retesting. [ i 22 MR. THOMAS: Excuse me, Sher. This is Cecil -f 23 Thomas, NRR. That was not the intent. It may very well be-t 24 before the exam is given. If we have reason to believe,_for i 25 one reason or another, that we want-to look at the exam i I ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 i i Washington, D.C. 20006 (202) 293-3950 i ---.-.,-m ..-_,m

-359. -1 before it is given and to do an inspection or monitor the 2 exam or whatever, we may very well want to see it before. 3 MR. WILKINS: I appreciate your clarification. I-4 had -- although he hadn't explicitly said that, I had sort l 5 of inferred that you had that in the back'of your mind -- ] 6 MR. BAHADUR: Thanks, Cecil. ] 7 MR. WILKINS: -- or that you could have had and 8 therefore should have had. 9 MR. BAHADUR: Thanks. As Cecil mentioned, this l 10 could be before actually administering the exam as well. l 11 MR. CARROLL: Now, this whole set of amendments i 12 applies equally well to non-power reactors? 13 MR. BAHADUR: Yes. As a matter of fact -- l 14 MR. CARROLL: It doesn't distinguish between its 15 licensed operators, whether they are a power reactor or non-16 power reactor. l 17 MR. BAHADUR: Yes. I think I -- in' response to l 18 your comment, maybe we can go to page eight first, where we 19 specifically asked the public to comment on this particular f i 20 issue, whether these amendments should also be applied to ? r 21 the non-power reactor. 22 MR. CARROLL: Okay. l f 23 MR. BAHADUR: One of the reasons why during the 24 proposed amendment phase it was not included was at that 25 time NRC had not completed the requalification examinations l i ANN RILEY & ASSOCIATES, LTD. f Court Reporters 4 1612 K Street, N.W., Suite 300 i Washington, D.C. 20006 (202) 293-3950 ,_l

m_.. m - _ - _ _.... ~ _... -. _... ~ _ k 360 1 at various non-power reactors. Our experience with the non-l 2 power reactors was not sufficient enough for us to decide 3 one way or the other. 4 While the proposed amendments were out for public 5 comment, meanwhile, the staff has completed a number of 6 requalification examinations on the non-reactor facilities. 7 And we found the passing rate was in excess of 95 percent. 8 Actually it was 97 percent. Right now I feel very confident { 9 in including the non-power reactor facilities as well in l i 10 these amendments. -l 11 MR. CARROLL: Okay. l t 12 MR. WILKINS: Does that mean that universities do 13 a better job than utilities? i 14 MR. CARROLL: No. It means they have simpler i i a - 15 reactors. j i i 16 MR. SEALE: Probably simpler exams. They have ] 17 simpler reactors and certainly they don't have the J 18 oeripheral problems. Emergency plans are'very simple. j l 19 MR. BAHADUR: The third amendment was to revise 20 the scope of Part 55 to include facility licensees as well. 21 Only one out of 42 respondents actually responded to this 22 particular aspect. One of the reasons why we believe we i 23 might not have received any comments on this amendment was 24 because this was merely an administrative change It does 25-not change any material changes in the intent of the l ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 i l (202) 293-3950 'l

i i ) 361 'l 1 regulation. The facility licensees are already included-in 2 Part 50 requirements, some of those, and then Part 55 i 3 requirements are as well applicable to them. This change in 4 the scope would only clarify that intention. So, the final 5 recommendation of the staff is to include facility licensees. l 6 in this. 1 7 As I mentioned, the success of these amendments .f 8 which I am summarizing here on page nine of your hand out, k 9 first of all, delete the requirements; secondly require 10 licensees to submit only upon request; and, of course, the 11 administrative change that facility licensees should also be 12 included depends upon the inspection program which has been 13 presented to the Commission as well in the same Commission 14 paper. l 15 And Bob is here to give you a little detail of f 16 that inspection program. Bob? 17 MR. GALLO: Okay. Thank you, Sher. Is this j 18 microphone as loud as that one? j i 19 MR. CARROLL: Yes. l 20 MR. GALLO: Sometimes they tell me I speak softly, l i 21 except my employees. 22 The requalification inspection program -- we have i 23 done some pilots in this area, so we have had some f 2 24 experience with our temporary instruction. We have done j 25 nine official pilot inspections, and there have been a few l a i MRI RILEY & ASSOCIATES, LTD. Court Reporters i t 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950 2 i

t-I 1-L362 i ] 1 more done by regional initiative, where no requal exams were 7 ' I 2 absolutely necessary. f l' 3 But, we will focus on program implementation and t l 4 we will -- I want to emphasize the implementation. One of j 5 the things -- we expect this to be about a one-week t j-6 inspection, probably two or three NRC examiners or { i l 7 inspectors. And the second bullet is important. We would-a r i' 8 make it coincide with the facility annual operating test, l 9 so we could see at least one week of'their operating test ) 10 activities. Facilities normally will run four, five or six { 11 weeks of testing, depending on how many crews they have. 4 ) 5 12 So, we are preparing to make sure we are there-when one of 4 i 13 those weeks occurs. 14 If there are -- there really are two choices we { l /" j \\ 15 have left for ourselves. If there are programmatic I 16 deficiencies that may lead to_a more detailed evaluation j d 17 using existing inspection procedure 41.500, which references l J 18 NUREG 1220, which is a fairly exhaustive systematic approach i i l-19 to training evaluation measurement or tool. That is one of s 20 the possibilities. Those type of inspections are ongoing l 4 i l 21 now for cause. This would be added as another reason for a { l 22 for cause training inspection. } l l~ 23 The other possibility that we have made sure in' { '] 24 the Part 55 rule is that we can still conduct 25 requalification exams for cause. That really has already j l l i i ANN RILEY & ASSOCIATES, LTD. Court Reporters I 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 l '(202) 293-3950

~ _... 363 1 been in there. We pointed it out to the paper and to the ~k 2 industry that if we decide -- and we do have some basic 3 ground rules that we are recommending to the -- will be in 4 the Commission paper, and I believe they are in the'FRN i 5 document that you have -- ground rules for when a for cause-6 examination will be conducted. One of them has to do with 7 SALP category three performance, and another one is a little 8 bit more general. It says a belief that.the requal training 9 program has become ineffective. So, some of that is going 10 to be basically up to the regional office to determine if 11 our for cause examination is needed. f t 12 The periodicity on the inspection program has been 13 changed to show that it is based on the SALP period. That 3 t 14 does provide a basis for the good performer facilities that j i 15 have 24-month SALP cycles -- would go to an every 2-year, or i 16 based on that SALP cycle. That's how often they would get j 17 the required inspection. A poor performer may be on a 12-l t 18 month SALP cycle. They'will get one every year. The 19 nominal. number in a.aw SALP management directive is 18 [t 20 months, plus or minus two I believe is the nominal SALP i 21 period. So, we have based our resource estimates on the 18-t i 22 month plus or.minus two estimate for SALP cycles. So, every l 23 facility will get -- two out of three years will probably 24 get an inspection. i i t 25-We did, as I mentioned, do the pilot program at i P ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 l 4' Washington, D.C. 20006 (202) 293-3950 \\ u

.~ 364-1 nine facilities. We did find some things that we -- 2 programmatic things and implementation aspects of the 3 programs that we had not been picking up during.the requal I 4 examinations. I think that is probably because the requal -l 5 examination focuses -- the NRC time has always been focused 6 on preparing the exam and-giving the exam and grading the 7 exam. We haven't looked behind the scenes at a few things 8 like overall management approval of the requal training 9 cycle and agreement with the operations department that the 10 training department is doing the right thing. So, we found 11 a few instances in that area. -i 12 At some of the better facilities we found pretty 13 much what we expected -- that there were very few problems j 14 administratively or in the testing of their own operators. i 15 MR. SEALE. Excuse me. ) 16 MR. GALLO: Yes, sir.. 17 MR. SEALE: I take it then in picking your nine l 1 18 victims for the pilot plant program -- 19 MR. GALLO: Volunteers. I think they were 20 volunteers. 21 MR. SEALE: -- you did try to cover the spectrum ) j 22 of performers? [ 23 MR. GALLO: Yes, sir. There were two very good 24 performers, and there was at least one plant that is on the 25 problem plan list. ANN RILEY & ASSOCIATES, LTD. Court Reporters j 1612 K Street, N.W., Suite 300 j Washington, D.C. 20006 ~ (202) 293-3950

c; a i -365 1 MR. SEALE: Okay. 2 MR. GALLO: And some of the others were just on 3 because of the calendar schedule -- 4. MR. SEALE: Sure. i l 5 MR. GALLO: -- and they happened to.be-in the j ' l 6 right window. The good performers were -- we did calloway,. j 7 and I think we did Diablo Canyon. I think I. have got my ( i 8 list here. And the weaker performer was-South Texas. There { 9 you go. Yes. Calloway, Diablo Canyon, Salem, Kewaunee, j 10 Turkey Point, Oak Creek, Nine-Mile, LaSalle, South Texas. . j i i 11 And there were a couple of others that were done as regional l J a 12 initiatives. Thank you. . j l ] 13 MR. SEALE: Yes. Thank you. j' 14 MR. GALLO: Were there any other questions on thatl ) i - t i L 15 slide? I 16 MR. BAHADUR: I just put up the new one. j l 17 MR. GALLO: Statutory compliance. I am not trying L" 18 to represent the Office of General Counsel; but we did get a i 19 letter from them in September I think of last year which l l 20 expressed their opinion. It was a letter from Mr. Parlor to I 21 Mr. -- to the Chairman, expressing their opinion of the l l 1' l 22 proposed amendment. Now, we have had them look at the l 23 proposal, basically the same version that you have. And- { i l 24 obviously we don't have their written concurrence yet, but e l 25 we haven't gotten any negative feedback. l l A' N RILEY & ASSOCIATES, LTD. Court Reporters j 1612 K Street, N.W., Suite 300 f Washington, D.C. 20006 (202) 293-3950 i ,.__.___._._.__,..__.-...._,_m _,...m,.-,y.

366 1 MR. BAHADUR: As a matter of fact', it has been -2 coordinated with the staff of the OGC. Since there aren't 3 very major changes between the proposed version, which was 4 the final, I don't see any legal glitches so-far. I talked 5 with Stu Treby and he was unable.to come today, however, he 6 mentioned that. 7 MR. CARROLL: Never trust those lawyers. They j i 8 will pull the rug out from under you.every time at the last 9 minute. i 10 MR. GALLO: Thank you for that advice, i 11 MR. SEALE: But, the big problem is that last i 12 definition. f r 13 MR. GALLO: Yes, sir. Yes, sir. And, I will put i 14 up a slide which -- I apologize, I have slides here which I I 15 thought were from the ACRS presentation last year. But, we 16 did say words to the effect of Part 55 will continue to 'I 1 17 contain legally binding requirements for requalification t 18 exams. That was at least part of the basis that OGC had 19 made their finding back in September of last year. 20 This bunch of slides here -- I don't know where I i i 21 made the presentation. I don't have any date on it. It-did l 22 discuss both requal inspections and requal program l 23 evaluations on a periodic basis. But, it was not-the ACRS j 24 slides. We had listed part of the proposed inspection i i-l 25 program to review the exams, observe the exams, an to i ) ANN RILEY & ASSOCIATES, LTD. Court Reporters i 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

367 conduct periodic selected portion of examinations. And that 1 i l 2 did appear in the Commission paper in December. 3 MR. CARROLL: I know that. j 1 l J l 4 MR. GALLO: You don't.think we discussed that with I 4 5 you? l 6 MR. CARROLL: Well, the -- 7 MR. GALLO: I am sure there is a transcript;.but I 8 thought we did. 9 MR. CARROLL: The chronology with me was I was 10 convinced you were not going to administer exams other than i 11 for cause after our October meeting. And I guess subsequent ? j 12 to your sending the December paper up, Forest Remick called i i 1 13 me up and said you guys wrote a letter endorsing these 14 amendments, and did you realize they were going to.still j 15 continue to do requal exams? I said absolutely not. At-j t 1 16 that time I went over what records I had and I could find l i 17 nothing that suggested to me that you had told us that. i 2 18 MR. GALLO: I know it was in the final paper. 19 MR. CARROLL: Oh, I know that. i' i i 20 MR. GALLO: We wrote that in December. ] 21 MR. CARROLL: I have it. l 22 MR. GALLO: We have to maybe find out which. paper j 23 -- I know there were several versions of it between October l 24 and December. It had been my plan all along and my l 1 l 25 recommendation from day one that we would.. That was my j ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 i (202) 293-3950 i [ ]

M^ -M m .+avu 4 m - = 368 ) 1 idea. 2 MR. CARROLL: Okay. It could certainly be a -- I 3 mean, it is probably a misunderstanding. The point is that 4 if I had understood that I think we would have said j 5 something about it in our October letter. ' i 6 MR. GALLO: We thought-you really were supporting _ l 7 it. 8 MR. CARROLL: I was because we were getting out of 9 the requal business. I may have just not been listening,or ' f 10 understanding. 11 MR. WILKINS: Is the issue here that a group -- l i 12 these people told us something in October; on the basis of ' i e 13 what they told us we wrote a letter, and then they told the - i 14 Commission something else? 15 MR. GALLO: It had always been my personal l 16 position that we ought to be doing those periodic requal 17 exams. That was way before the ACRS meeting. I i 18 MR. WILKINS: Yes. But, now, as a result of -- 19 MR. GALLO: So, I don't know how that came about. i i 20 MR. WILKINS: -- all of the intermediate steps, 21 you are back to where we thought you were? l 22 MR. CARROLL: Yes, sir. That's. correct. i 23 MR. GALLO: Yes, sir. 24 MR. CARROLL: That is correct. s } 25 MR. GALLO: Yes. We are now in agreement with the j n i ) ANN RILEY & ASSOCIATES, LTD. Court. Reporters l 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 4 (202) 293-3950 1 -

l ) 369 1 ACRS. 2 MR. SEALE: Sometimes truth and virtue win out. 3 MR. CARROLL: Yes. Well, no, the only point is j 4 that, if there was a change between October and December, it 5 would have been nice if we knew it because we probabl'y would i 6 have written another letter. i 7 MR. GALLO: My point was I certainly never changed l t 8 my mind until the Commission told us to change our mind. 9 MR. WILKINS: Please go ahead. } 10 MR. THOMAS: I am not sure if I am going to help 11 this much, but let me offer a couple of things. i 12 Commissioner Remick's comments on our SECY paper talked j 13 about specifically disapproving the staff's proposal to 14 periodically conduct selected portions of requal operating 15 tests routinely. I am paraphrasing. We abided by that 16 suggestion. That is not included here, l i l 17 But, just one note. My experience has been that [ 18 there has been often confusion between people not focusing i i i 19 on the difference between inspections and examinations. .j 20 Sometimes there has been confusion between the training rule l i 21 and this. In the case of the training rule, as you recall, i 22 we are not doing routine inspections, we are only doing for 23 cause. Here we are doing routine inspections but only for ] 24 cause examinations. 25 MR. CARROLL: Correct. (h ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 { (202) 293-3950 1 i l .,-.-r

l 'I 370 l 1 MR. THOMAS: And it is important. Because the two a f~ \\ 2 are somewhat similar, it is easy for people to get confused. 3 MR. WILKINS: I do understand the present i 4 situation. l 4 5 MR. CARROLL: Yes, sir. 6 6 MR. WILKINS: I thought I understood the situation l'; 7 12 months ago. You assure me that they.are substantially. 8 the same? I i 9 MR. CARROLL: Yes. 10 MR. WILKINS: So, if there had been perturbation 11 in between, then for substantive purposes we can ignore it j i f 12 and if we want to fuss it is because you changed something -i 13 for the Commission and didn't tell us you changed it and i 14 then made us look silly. But, that is a separate issue, and [a 15 I think we can avoid discussing that in this forum. Even if i 16 it happened, we can avoid discussing it. I am not asserting ^ [ 17 that it happened. -l 18 MR. DAVIS: On your pilot program list, I don't 19 think I heard any BWR listed; is that right? l 20 MR. GALLO: At LaSalle, Nine Mile and 0ak Creek 21 are on there. j i 22 MR. DAVIS: Okay. I missed it. ~ 1 4 23 MR. GALLO: Yes. I am sorry. LaSalle, Nine Mile i 24 and Oak Creek are boilers. Somebody put South Texas under-25 the boiler side, but I know that is not right. l l l ) ANN RILEY &' ASSOCIAT7S, LTD. Court Reporte's 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 2 (202) 293-3950 I I i

. - -. _.. ~. = _. -. - -. 371 i 1 MR. DAVIS: No. Okay. Thank you. 3 2 MR. GALLO: It's Turkey Point, Calloway, Diablo. 3 The last slide is on the proposed schedule. I i 4 think Sher has already mentioned this. We are planning on { 5 going to CRGR for further review. Our original goal was to-6 get this to the EDO by the end of October. If we have to 7 wait on the CRGR, that may slip. We will publish it, [ 8 depending on the Commission's review, in mid-December or 9 late December. i 10 The implementation. Of course, this will be-i 11 whatever is required by our statutory requirements. We are l i 12 still now conducting requalification exams because there are 13 people that require license renewal and to get a license 14 renewal they need to have an NRC requal exam. So, we are 3 15 still out there scheduling requal exams now and conducting I 16 them. l 1 i j 17 Thank you very much. That is the end of our l 18 prepared presentation. f a t .19 MR. WILKINS: Wait a minute. Are you suggesting - 20 - probably not, but let me make sure -- that the license j 21 renewal rule requires the NRC to administer requalification l P 22 exams? I I 23 MR. GALLO: For an individual, yes, sir. That was j 24 the original 1987 rule. Before they get the license renewed 25 they have to have the exam. l i ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 i Washington, D.C. 20006 (202) 293-3950 m.,.

372 l l 1 MR. THOMAS: We are talking about two different 2 license renewals. 3 MR. WILKINS: You are absolutely right. 4 MR. GALLO: Part 55 license. { i I-5 MR. WILKINS: Yes. You are talking about the 6 individual license? a 7 MR. GALLO: Yes, sir. 4 8 MR. WILKINS: I am talking about the plant. 1-I 9 MR. THOMAS: We are talking about operator l 10 licenses and you are talking about Part 50. I 11 MR. WILKINS: Yes. Exactly. All right. Thank i 12 you for qualifying that. j ? 13 MR. GALLO: I am sorry. I missed your "the { t 14 license renewal." l j 15 MR. WILKINS: So did I, so don't apologize. i 16 MR. CARROLL: Okay. Anyone have any further I I j 17 questions? 18 [No response.] r i 19 MR. CARROLL: I guess I always need to -- you made i e 20 the statement, Bob, earlier that in the last year since you 't 21 were last here the pass rate has continued to go'up, or has [ 22 it leveled off? l 1 1 23 MR. GALLO: I think the individual pass rate has 24 pretty much leveled off around 93 percent. I think my 25 numbers show '91 was around 90 percent, and '92 was around 't I l ANN RILEY & ASSOCIATES, LTD. i Court Reporters 1612 K Street, N.W.,. Suite 300 Washington, D.C. 20006 'I (202) 293-3950 j. 5 , _. _... _. _ _. =..

.~ W s 373 1 93 percent. So far this year when we checked I think,'as of l y 2 July or June, it was 93 percent for this year. The number 3 of program pass rate has gone to a hundred percent effective j 4 this year. In the past it had gone from 80 to 85 to 90 x; ~ 5 something, and now it is essentially at 100 percent.of the- .I 6 programs that have been evaluated for this year. I' guess 7 the non-power number is around 97 percent I think for 8 individuals. I don't think we expect any perturbation in j ~! 9 that. ) 10 MR. CARFOLL: how will this rule affect the 11 manpower situation, in terms of people that are either NRC 12 employees or consultants that have in the past given these 13 examinations? } I 14 MR. GALLO: We had numbers. There are some { 15 numbers in the regulatory analysis. We need to go back -- 16 and it is going to -- the total number of reduction in there 1 17 - some of those resources have already been removed from j l 18 the budget. So, in anticipation of the rule, our FY '94 l i I l 19 operator licensing resources for the regions was reduced by i l 20 five FTE. It may.be another I think maybe two,spaybe three L 21 more FTE maybe. I think it is two. But, we are getting 22 into really fine numbers here when trying to predict 23 something that may be tough to predict. I hate to get to f; 24 the point where we don't have enough resources to do the j' 25 minimum program. But, there are -- t b Y h ANN RILEY & ASSOCIATES, LTD. Court Reporters 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 (202) 293-3950 i

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l i [ 374 1 MR. CARROLL: Or deal with for cause kind of j i A 2 situations. .j i 3 MR. GALLO: I am trying to keep that in the back. -i 4 pocket to keep the contractors available to do some 5 inspections or for cause examinations. So, we want to make 6 sure we lose the contractors as a back-up resource. 7 MR. CARROLL: Okay. 8 MR. GALLO: Yes, sir? 9 MR. LINDBLAD: Most of our discussion has been on 10 power reactors. Are there training programs of non-power L 11 reactors as improved-not having an INPO to help them? Do we~ 12 have any concern with the University reactors in this? 13 MR. GALLO: As far as the operator performance, it I I I i 14 has been very good, as we have mentioned. As far as the i i i 15 programs are concerned, they are not a systems approach to i j 16 training programs. They don't use the Part 55.4 defined f 17 methodology. They are not required to use that. So, you 18 will find a pretty wide variation in their training I 19 programs. Some of them look like power reactors. Some of l 20 them look like they were written on the back of an envelop. I 21 But, the human factors branch in my division -- f 22 MR. LINDBLAD: Notwithstandinc, th -' are all good l l l 23 you are saying? I 24 MR. WILKINS: Produced good results anyway. 'h l 25 MR. GALLO: They are basically appropriate for the i l l ANN RILEY & ASSOCIATES, LTD. Court Reporters [ 1612 K Street, N.W., Suite 300 l Washington, D.C. 20006 (202) 293-3950 1 - a

..m.4 .,m.c m i i- 't 375 We do review changes to those programs on a -- not my 1 need. 2 branch, but another branch in a division reviews changes to j 3 those programs. There have been some' fairly significant j 4 changes recently because of some incidents that have 5 occurred. That has been the corrective action on a couple 6 of recent incidents of those, to make some modifications'in 1 7 the training program. 8 MR. CARROLL: The thing at the University of .j i 9 Michigan wasn't? 1 10 MR. GALLO: Yes, siri i 11-MR. LINDBLAD: Is the requalification program of a-l ~! 12 non-power reactor operator -- are they frequently students-i I l i 13 with only a short time in the facility, as compared to power j i 14 reactors? 15 MR. GALLO: They are required to go to 16 requalification training. But, a long time'ago there was a 4 17 letter from the then EDO, Vic Stello, that said we wou'.d not I'I s 1 18 test people who were not going to renew their licenses. So, i I L 19 we have not tried to test students who we knew were going to 1 20 graduate or something like that. So, the people we have j a 21 tested are essentially all staff people that are there I 22 permanently, even at the Universities. I 1 23 MR. LINDBLAD: Thank you. 24 MR. CARROLL: It seems to me the real concern are 25 the quality of the people that are in charge of these ANN RILEY & ASSOCIATES, LTD. 3-i Court Reporters 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 (202) 293-3950

~ l-376 1 facilities. I mean we have had Catton running one of the 2 reactors -- 3 MR. CATTON: Now, now. 4 MR. CARROLL: -- and Kerr and Remick. 9 'l 5 MR. GALLO: An outstanding facility I am sure. -l + 6 MR. CARROLL: That is what worries me. l 7 MR. SEALE: I let my license lapse when I joined ) r 8 this body. I didn't -- I felt I shouldn't court too many L l 9 mine fields at the same time. l l 10 But, my comment on that would be that the thing l 11 that has happened in the last few years with the University. j l 12 programs is that the content of the requalification program 13 has become a lot more specific in terms of things like j i 14 emergency planning and certain specific kinds of events so l {- 15 they are a lot more comprehensive in that regard thannthey l i i 16 have been in the past. They are certainly not.the 3 1 17 systematic approach to training as you indicate, but the I 18 scope of the programs are a lot broader. t I l 19 MR. CATTON: I never had any problem with the j i 20 students passing, but I had a lot of difficulty with some of 21 my staff. f 22 MR. WILKINS: That's true. Is that it? l l 23 MR. CARROLL: That's all I have. Anymore l 24 questions? l I i 25 [No response. ] 3 i ANN RILEY & ASSOCIATES, LTD. Court Reporters i 1612 K Street, N.W., Suite 300 Washington, D.C. 20006 l' (202) 293-3950 i i f -,.. ~ - ,._y p

_. ~,.._ l377 1 MR. CARROLL: Thank you. k 2 MR. BAHADUR: Thank'you so much, Mr. Chairman. 3 MR. WILKINS: All right. 4 [Whereupon, at 11:28 a.m., the above-entitled ) 5 . meeting was adjourned.] l 6 i 7 i 8 1 9 l i 10 .l 11 l 12 N 1 13 i i .i' 14 i i i 15 i 16 l 17 l .I 18 ) 19 [ l 20 l I 21 -I 22 23 -l -l t 24 l 4 1 r b 4 j [ 25 i i s ANN RIL ?Y & ASSOCIATES, LTD. C ourt Reporters i I 1612 K Street, N.W., Suite 300 F Washington, D.C. 20006 l (202) 293-3950 l' l' I

. (.- 5 REPORTER'S CERTIFICATE T.s is to certify that the attached proceedings before the United States Nuclear ~ Regulatory Commission in the matter of: NAME OF PROCEEDING: ACRS 402nd Meeting DOCKET NUMBER: PLACE OF PROCEEDING: Bethesda, MD were held as herein appears, and that this is the original transcript thereof for the file of the United States Nuclear Regulatory Ccamission taken by me and thereafter reduced to typewriting by me or under the direction of the court reporting (s company, and that the transcript is a true and \\,) accurate record of the foregoing proceedings. b wA w !h,,4,1,,, Official Reporter d Ann Riley & Associates, Ltd. t 5

0 o o PRESENTATION TO THE ACRS BRIEFING ON LICENSED OPERATOR REQUALIFICATION OCTOBER 8,1993 s nau,'* = a l \\...../ SHER BAHADUR, CHIEF REGULATION DEVELOPMENT BRANCH, DRA/RES 301 492-3775 AND ROBERT M. GALLO, CHIEF OPERATOR LICENSING BRANCH, DRCH/NRR o 301 ~ 504-1031 v-

.O o o BACKGROUND e Briefed ACRS on Proposed Rule, October 1992 e Briefed CRGR on Proposed Rule, October 1992 Submitted Proposed Rule to the Commission, ~ December 1992 (SECY-92-430) Published Proposed Rule in Federal Register, May 1993 e for a 60-day public comment period 42 comments received i 2, - ~ z

.O O Q-

SUMMARY

OF COMMENTS 1. Proposed Amendment: Delete 6 55.57(b)(2)(iv) requiring licensed operators at Part 50 facilities to pass a comprehensive requalification written' examination and operating. test administered by the NRC during 1 the term of a 6-year license. 36 of 42 favored the proposed amendment (of the 36 respondents,22 were power reactor licensees, 13 were non-power reactor licensees; and 1 representing-the National Organization of Test, Research, and Training Reactors). i 6 opposed (most notable from States of Vermont and Illinois). Lack of confidence in licensee's grading procedures to detect unsatisfactory licensee requalification programs. Current requirement provides a strong incentive for licensees to maintain the quality of their operator training program. 3 ... -.... ~ -. - -.... -. -. - - -. -

O o o

SUMMARY

OF COMMENTS (CONT'D.) e Staff Resolution: Deficiency in an operator's performance mostly due to weakness in implementation of licensee's requalification programs. Redirection of NRC resources towards inspection and oversight expected to' improve facility programs. Recommendation: Delete Section 55.57(b)(2)(iv). l 4 l l

-0 0 O 1 l l 1^

SUMMARY

OF COMMENTS (CONT'D.) 2. Proposed Amendment: Require facility licensee to submit to the NRC-for review copies of each written examination or annual operating test used for operator requalification 30 days prior to administration. 41 of the 42 respondents opposed.this amendment. e Additional burden on licensee and NRC without increase in safety benefit. 1 respondent (non-power reactor licensee) favore'd this amendment. Less burdensome than the current licensee requalification: requirements. 5 . ~.

O o 0

SUMMARY

OF COMMENTS (CONT'D.) Staff Resolution: 30-day period was proposed so that NRC could evaluate examinations and tests to determine scope of on-site inspection. Pilot inspection Program has demonstrated no such need. l Recommendation: Submission of examinations and tests should be required only upon regu_eit. 6

^ O o o

SUMMARY

OF COMMENTS (CONT'D.) 3. Proposed Amendment: Revise scope of Part 55 to include " facility licensees." Only 1 of 42 respondents to the FRN commented and endorsed this amendment. Staff Resolution: This amendment is an administrative addition to the regulation, which is intended to eliminate ambiguities between Parts 50 and 55. 'h F -7 -..... -. -. -.......-.=

O o o ~

SUMMARY

OF COMMENTS (CONT'Q,) 4 Specific Comments Requested: Applicability of the proposed amendments to research and test reactor facilities. Based on 97% pass rate in recently completed requalification examinations, staff recommends that the final amendments be l applicable to both power and non-power reactor facilities-l I l b g fa ,,......_..m,, ...~.,......,...,,,.,_,.J.._..._.__ .. s.

o o a: l l FINAL CHANGES TO 10 CFR PART 55 i Delete requirement for NRC to examine each operator for e license renewal-(i.e., 5 55.57(b)(2)(iv)). Add requirement to 9 55.59 that a facility licensee shall, upon e request, submit a copy of its annual operating tests and comprehensive requalification written examinations to the Commission. Revise Scope of Part 55 to include " facility licensees." e lf 9- .4 .r,-.-.-,-.. ---.-.c -~,~,.w-+...--.--..-+,-.m.4.--..m.e,. -.4- .mm..-..... ..+.r...., ...m,- ,-v.e--,,- -mm ...-- m

-O o a T BEDUALIFICATION INSPECTION PROGRAM Inspection Program will focus on program implementation. Inspection Program would normally coincide with facility operating tests. Significant requalification program deficiencies may lead to more detailed evaluation using IP 41500 (training and i qualification effectiveness). NRC will conduct requalification examinations for cause. Pilot Program at nine'(9) facilities. 10 .........-.--....---...~...Jm.~ .---.-....--,--.m. -....--,_.--.__.....-_........L.-,....... _., _... i m m i m- ...a

O o o STATUTORY COMPLIANCE e Nuclear Waste Policy Act of 1982 Requires regulations or guidance establishing requirements for, and governing NRC administration of, requalification examinations. Statutory intent is silent regarding definition of " administration." l l Part 55 Part 55.59(a)(2) continues to require examinations. " Administration" by NRC oversight meets intent. l l l l 11

O o o i l PROPOSED SCHEDULE ^ l-Complete Offices, CRGR, and ACRS review, October 15,1993 e e Final Rule to the EDO, October 29,1993 e Publish Final Rule, December 15,1993 h 12: ,..-,,;,._,.,a,, -.-,~-,..----.-,.--,~.n-..-.,..-.w+ ....-,-.....-,i--n-,. .... -. - -...,.. - ~.. -,.. - -.

ACRS PRESENTATION O ou STEAM GENERATOR TUBE RUPTURE A.T PALO VERDE UNIT 2 OCTOBER 8,1993 INTRODUCTION Alfred E. Chaffee, Chief Events Assessment Branch O oi ision of Opereting Reector Suggert Office of Nuclear Reactor Regulation (301)504-1168 AIT INSPECTION Dennis F. Kirsch AIT Team Leader Region V (510)975-0290 SG TUBE LEAK DETECTION James Reese, Chief AND INDICATION Facilities Radiological Protection Branch Region V (510)975-0237 TUBE RUPTURE CAUSES Kenneth J. Karwoski AND NRC ACTIONS Materials and Chemical Engineering Branch Division of Engineering O Office of Nocieer Reector Reouietion (301)504-2754

I . O Presenter Dennis F. Kirsch A.lT Team Leader i Region V i SEQUENCE OF EVENTS O AIT CONCLUSIONS AND FINDINGS Emergency Operating Procedures Radiation Monitoring System Contributors Emergency Plan implementing Procedures Human Factors Training Deficiencies [ O 2 i i

SEQUENCE OF EVENTS ~ IME EVENT 0434 - 03/14/93 SG-2 Tube Ruptures. (But not detected) Leak Rate About 240 gpm. Main Steam Line Radiation Monitor Alarms. 0447 Manual Reactor Trip. 0448 SIAS and CIAS Auto-Initiate. Main Steam Line Radiation Monitor Alarm Clears and Blowdown isolates. 0502 Alert Declared. Entered Functional Recovery Procedures. 03 Commenced Cooldown Per FRP. 0624 Operators Exit FRP After PZR Level > 33% and Re-Enter DLT. 0640 SGTR Diagnosed By Operators. 0728 SG-2 Isolated. 1029 Entered Mode 4. 2235 initiated Shutdown Cooling. 0115 - 03/15/93 Terminated Alert. O 3

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Snapshot approach flawed diagnostic logic tree use
EOPs do not allow for re-diagnosis of an event after entering FRPs
Continuously applicable condition use in FRP would have allowed transition to SGTR procedure e implementation of EPGs in EOPs did not consider alarm setpoint basis of trends below alarm setpoint S

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l g 1 l Radiation Monitoring System Contributors

Alert and alarm setpoints of main steam line and condenser exhaust monitors based on not exceeding regulatory dose limits at site boundary e IN 88-99 and 91-43 response did not result in complete evaluation of condenser vacuum exhaust monitor setpoint-

.. ~, 5

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EPIPs did not differentiate between a SBLOCA and SGTR Guidance of NUREG-0654 not implemented to classify SGTR as an alert and treat separately from SBLOCA
Leakrate in excess of available charging pump capacity would have been classified as an SAE
Event was not classified as required by EPIPs but was l

properly an ALERT by NUREG-0654 criteria for SGTR. EOF and TSC were not activated within the one hour goal l 1 1 Assembly and accountability completion occurred in 6 hrs. 44 min. instead of 30 min. required by procedures l l _~.. m m m A m m.. m.sw _ mu. .u m.m.u ~_ .um- _m, c - mm-.m.mmm. mm. m ~...m.<.m. .,m m. mm _ _ _, om .m.m l 6

4 e m ' ws pa ar.< ,- e a s - esA; we_&. --a, u A..,.E s 3..wh ;;Ne.* & s.c o.nw=rsw.'.. 3.usm ; s..avam. :.,.'45 4*p. rep cW e..#- wy,4,sLh ev rmws -s s c,+ % AN w 4 T s, r y h.. .,ys ym.,..,,6w,a s.rms w wv.- ve,u____.. w Human Factors and Training Deficiencies In the simulator, condenser vacuum and main steam line radiation monitor alarms and remain in alarm for SGTR

Small unmonitored steam release pathways, such as unit auxiliary steam relief line, were not adequately addressed in simulator exercises or the classroom l
Simulator training did not discuss the possibility that HPSI flow may occur up to about 1860 psi.

HPSI flow indicated as 'zero' below 65 gpm and flow rates of.about 20-30 gpm would be expected to upto about 1860 psi e Radiation Monitoring System in the control room was not user friendly and inhibited the monitoring of trends 7 l s -s .wmm .......,._--.-.-----=----,v...w----....- .----w --- -e-- --,r--ww~e.-

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. --__~.~.._-:._,.....- - -.. Presenter James Reese, Chief Facilities Radiological Protection Branch Region V 4 HISTORY OF STEAM GENERATOR LEAK DETECTION AT PV2 LEAK RATE DETERMINATION METHODS AND PROBLEMS CORRECTIVE ACTIONS 3,w k s. 4 *-w Mw. 4 % ^ \\ gr-

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a -#E -7.46 hW L.XM-'NJ-'s. K+ M % G.' h EA N.hT4s+& w hhw M,.ro %,----wsma...----wW) .,._..ww+-. s History of SG Leak Detection at PV2

July 1992 First Indication of Tube Leak
December 10,1992 CE Letter on Sample Dilution
January 20,1992 Chemistry Response to CE Letter
February 1993 Leak Rate Shows increasing Trend
March 4,1993 Leak Rate Spike
March 14,1993 Tube Rupture

~. ~. - -. . ~_.. _ - -. - - -. -- 9

4 m - _. ~ - - ~ - -.. - ~ Leak Rate Determination Methods and Problems

Tritium activity in secondary plant
Fission product activity in steam generator
Fission gas isotopic activity from condenser off gas
Condenser off-gas radiation monitor readings e Boron in steam generator

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Equation based upon continuous build-up
Loss not considered 1

Fission product activity in steam generator

Primary method utilized lodine-131
Feedwater spill-over
lodine hide-out mm 12 e.,

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,.,____m L Condenser off-gas radiation monitor readings

Inaccurate readings
Detector failure l

Procedural Concerns

Hierarchy not specified
Verification of results not required
Limitations of methods not fully delineated

_. _ _ _ ~ 13

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Administrative Limits on Leak Rate

< 10 gpd 10-50 gpd > 50 gpd 14

d . ~. - - - ~ - -. . _ - - - - - -, _. _ - - - - -. - - - ~ Presenter Kenneth J. Karwoski Materials and Chemical Engineering Branch Office of Nuclear Reactor Regulation STEAM GENERATOR HISTORY RUPTURED TUBE STEAM GENERATOR INSPECTIONS ROOT CAUSE OF FAILURE CONCLUSIONS LICENSEE ACTIONS

Nvw m 'e. 4. v.w., e.44. C-* ar. 2 = W4 4M4kw v.wwmWJ4M-4 %<E'?$x hwv-asAwAE - 5-J w w.5:- E :M4-44h a v.m a s,41d W. - =. 4pw e..T, +.n a c w4 v.. .s.+4wer%2.= wr,mMid -- a; w.S 7 m se s evsw.%,--.w. e Steam Generator History

CE System 80 steam generators
Units 1, 2, and 3 are the only operating plants with this design
Primary mode of degradation observed during previous inspections was wear
One axial crack was found in tube free-span during the previous outage: Two other indications were reclassified as cracks following the SGTR event m_____.______

16

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Ruptured Tube had a 2.0" To 2.5" Axial fishmouth opening i

F e Entire crack length was approximately 8 inches

No detectable degradation was observed at the rupture location during the previous outage Measurable primary-to-secondary leakage prior to event-but no conclusive evidence of a slow, stable increase in leakage N.'44.4 e5 s MM4 '%2.

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+6w-- - - --,. v._ --4 Steam Generator Inspections e 100% Bobbin Coil inspection e Bobbin Coil identified an area of interest (referred to as the arc?

The arc consists of the upper portion of the outer i

' periphery tubes e MRPC examinations performed in the arc I e Arc was expanded as necessary to provide 5 tube buffer around: indications 18

ww.w u,. 4,.-4 wo:.xvew .sa,.:.n. _x. o -mt m..:.e,m.u w 4. m us2.,w.acw o. ~a a:..x,. ~c.. w mu . n _ a -~. _... y am,- __w ,_m.m. _ _ Root Cause of Failure 1 l

IGA /lGSCC due to tube-to-tube crevice formation
Increased susceptibility of contaminant concentration in the upper region of the tube bundle
Alkaline to caustic conditions with elevated sulfur levels
Deposits in crevice, together with heat flux, led to aggressive environment under the. deposits

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s..m s--s;

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weg,-2 4 mm - . '.7 w3477 5 4 e.v %' m;& d ',4,;g '.G v.my, .- 44 v w. &.a ps'-a ;3 hc. -> + u 5%cr. h> + as AA r- @ah+.p wn t--- www,m +.w.5 4. y.2., _ _ _ g:4 p.3,qu 43pm,% ,. y,n. _,.. y..c y.., ,_w.- g Root Cause of Failure (Continued)

Cold working due to surface scratches led to more rapid crack initiation e Non-optimal microstructure of ruptured tube reduced the materials resistance to cracking

- - - _. ~.. _ - -

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Using regulatory guide 1.121. Guidance, the licensee concluded that a six-month operating interval was acceptable
- Staff could not conclude that all tubes will meet regulatory guide criteria at end of 6 months
Operation for six-months is acceptable based on:

Risk associated'with operating with potentially degraded tubes t kh- ...:h3 MS-W 4G,<M*+ 4 4 =>,+A.'hWA ;,-

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Primary-to-secondary leakage monitoring improvements
Improvements in EOPs
Reduction in VOPT setpoint and coolant iodine activity
Operator training

_ ~ 22

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O O O S/G #2 LEAK RATE USING TRITIUM-130.0a 120.0a 110.00,; loo.oo ~ 90.o0 80.00 70 5 so.o0 /b .co So.oo g 4o.m // % \\ / s ) //A \\\\ /\\ /L 3o.oo /// N\\"M\\// 2o.= .i i _af'_ '~i J , o. i L </xW Q' - ( o.x = = , p-- ,gr ., o.= 20.x - f 8 8 8 l s e 8 3 e 5 E k N 5 _l DATE / TIME QC "YO N,

s ~ Figure 3 SYSTEM 80 STEAM GENERATOR \\y 40*g/ 1 jf[ - Al @V. 4 v pr i NO. NO. SERVICE REQ'D DRYERC .A&BAaaAsaaaa 1 Primary inlet 1 2 Primary Outlet 2 .I SEPARATORS 3 Downcomer Feedwater 1 1 4 Steam outlet 2 5 l. OOD00__ 4 i 20'5' 5 Blowdown 2 0 D. 6 Primary Manway 2 7 Secondary Manway 2 8 Handhole 2 3s 9 Economizer Feedwater 2 e-- y j t r' 3 f, d l % (' ~ ~ %l h ,~ g.4 l \\/ e i 15' 10-w 0.D. ,s. ~ ( p+% 8 .g1 r a i T' n s ~%,,,s ) ,h l @g i l D@ 4s- ,1, g e t@,,,kMT @ g k S$f i BOTTOM VIEW OF fi4J'+. STEAM GENERATOR 7 m g V .i. O

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rigure o UpperTube Bundle Geometry Hot Side (90 -270 Axis) O = Relatively long unsupported length E$18*-> 8 + zi.s'

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ML20057E870

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