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| {{#Wiki_filter:ORIGINAL ae,estau I | | {{#Wiki_filter:}} |
| UNITED STATES OF AMERICA
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| ' NUCLEAR REGULATORY COMMISSION In the matter of:
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| ADVISOPY COMMITTEE ON REACTOR SAFEGUARDS 305th General Meeting Docket No.
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| Location: Washington, D. C.
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| Pages: 1 - 278 Date: Thursday, September 12, 1985 j ACRSDEE00PY x Y
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| * Jo No: Remove ANN RILEY & ASSOCIATES ACRSOr%
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| OV Court Reportere 1625 I St., N.W.
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| Suite 921 8509190485 850912 Washington, D.C. 20006
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| $3744 pop (202) 293-3950 e
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| - - . . . . . .. . . - - - _ . - ~ _ . .-- . . . _ . .
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| 1 1 UNITED STATES OF AMERICA 2 NUCLEAR REGULATORY COMMISSION 3
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| 4 ADVISORY COMMITTEE ON REACTOR SAFEGUARDS i 5 ,
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| i 6 305th GENERAL MEETING i
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| 7 8 Room 1046 9 1717 H Street, N. W.
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| i 10 Washington, D. C.
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| 11 Thursday, 12 September 1985 12 i
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| 13 The Advisory Committee on Reactor Safeguards was
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| ' i l 14 convened at 8:40 a.m., David Ward, Chairman of the Committee, I
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| 15 presiding.
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| i I
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| i 16 PRESENT FOR THE ACRS COMMITTEE:
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| 1 17 D. Ward, Chairman i
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| 18 H. Lewis 1
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| i
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| ! 19 J. Ebersole J ,
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| 1 j 20 D. Moeller i
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| 21 Okrent D.
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| 22 C. Michelson 4 !
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| 2 23 O. Reed I 24 C. Wylie I
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| . 25 F. Remick ;
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| t
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| . _ _ _ - _ _ - - . _ _ _ _ _ _ .__ _ _ - _ . _ _ _ . _ . _ _ . -_ ____ _ _ . .._.___.._____...._____..J
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| 2 9
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| i 1 PRESENT FOR THE ACRS COMMIRTTEE; (Continued) 2 P. Shewmon 3 J. C. Mark ;
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| i 4 C. Siess 5 R. Axtmann I,
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| ; 6 W. Kerr i-t 7 PRESENT FOR NRC STAFF; j 9
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| 8 R. Blau i
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| i 9 G. Gears f
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| \
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| 10 W. Ha 1eton 4
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| 11 D. Scaletti 12 J. Rosenthal 13 M. Rubin
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| . 14 J. Read (
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| i i
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| f 15 A. Serkis i t
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| 16 K. Kniel t
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| ! 17 R. Bosnak 18 J. O'Brien !
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| i 19 PRESENT FOR GE: I i i i 20 R. Villa [
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| l I i
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| i 21 G. Sherwood I
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| ! I 22 D. Hankins f 1
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| i j 23 K. Holtsolaw ,
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| ! I 4 ,
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| ! 24 PRESENT FOR BNL;
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| [
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| ] 25 C. Shu e
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| i
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| ; i k
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| f
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| 3 i P2OC EED I NG S 2 MR. WARD: We will now hear from Mr. Ebersole.
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| 3 MR. EBERSOLE: I will comment on each of the things 4 of particular interest to the committee. The first one is 5 inadvertent actuation of the file suppression system at Hope 6 Creek. You may recall I called out in TVA again that there 7 had been rooms overpressurized and doors blown off by 8 malfunctions of the delivery system from the large storage 9 systems for CO2, and certainly an implied threat to blow apart 10 safety rooms such as battery rooms or others that might be 11 protected and had a strong enclosure including the doors.
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| 12 Thus, apparently what should be a relatively 13 hazard-free system may have some substantial hazard potential O 14 if it is maloperated by inappropriate operative devices or not 15 provided relief panels or whatever to get rid of mistakes in 16 the control system.
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| 17 I'm going to turn all this over to Ernie Taylor for 18 Item No. 1, the Hope Creek inadvertent actuation of the fire 19 suppression system.
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| 20 MR. ROSSI: I'm Ernie Rossi, Chief of the Events 21 Analysis Branch in the Office of Inspection and Enforcement.
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| 22 We have five events on which formal presentations 23 will be given this morning. These will be discussed by 24 various members of the Office of Inspection and Enforcement 25 and the Office of Nuclear Reactor Regulation. I will
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| 4 1 introduco thom as they mcko their prosentations.
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| . 2 In addition to the five presentations, we have with 3 us Nick Chrissotimos from Region III, who at the end of the 4 five presentations is going to say a few words about FERMI 2 5 premature criticality which occurred on July 2nd of this I
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| 6 year. We understand there were a couple members of the 7 committee who were interested in hearing something about that 8 event today.
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| 9 Also, to help us in answering questions which you 10 might have, we have a number of other people with us. Among 11 these are Alex Dromery from the Office of Inspection and l
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| t 12 Enforcement. We have Ron Hernon, Dave Wagner, Dan McDaniel 13 and Warren Hazelton from the Office of Nuclear Reactor s
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| 14 Regulations, and I believe we were going to have one person 15 from Region I here.
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| 16 MR. BLAU: My name is Randy Blau from Region I, 17 Senior Resident Inspector, Hope Creek.
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| 18 MR. ROSSI; Fine, So we will begin with the 19 presentation on the Hope Creek inadvertent actuation of the 20 fire suppression system, and that will be given by Jim 21 Henderson of the Office of Inspection and Enforcement.
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| 22 We also have Jack Strosnider who joined us from the 23 region to help answer questions on Hope Creek.
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| 24 [ Slide.3 i 25 MR. HENDERSON: I don't know whether this I
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| i l .,
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| 5 1 transparoney will bo of any help, but it will givo you semo 2 outline of the situation while I talk.
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| O 3 I'm Jim Henderson of the Inspection and Enforcement 4 Engineering and Generic Communications Branch.
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| 5 When we met with the subcommittee on Tuesday, some f
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| 6 concerns were expressed and questions asked that we couldn't 7 answer, although I tried. In my presentation I will try and 8 answer them, and to the extent I can't. I have some backup 9 from the region. The resident inspector will be able to help 10 on things like building arrangement and things of thrt nature 11 since I have not been to the site.
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| 12 Hope Creek is a one-unit BWR site contiguous to the 13 Salem site. It is in the last stages of construction, and on 14 the 4th of September at just the day before we received the 15 first shipment of fuel, various elements of the plant are not 16 yet fully complete. For example, there is still temporary 17 construction access openings in compartment boundaries, an 18 ventilaion systems are not fully operational.
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| ) 19 On the morning of September 4th, a walk-through 20 emergency site drill related to the receipt of fuel was in 21 progress. Construction personnel had been notified and they i
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| j 22 were not involved. At about 8:45 a.m. there was an automatic
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| ! I 1 23 initiation of CO2 fire suppressant to a diesel fuel oil tank 24 room. The CO2 injection continued beyond the design time and
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| [ } 25 quantity limits.
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| V i
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| I
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| 6 1 Thoro was no apparont damage to any structuro, i
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| 2 systems or components, but adjacent workmen were affected.
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| 3 Evacuation was promptly initiated. It was somewhat slowed 4 down by the precognizance of the drill in progress and the 5 assumption that the evacuation was not real but part of the 6 drill.
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| 7 The building was evacuated and 23 individuals were 8 transported to hospitals. We have no real information on 9 their present state. It seems they.got behind the cloak of 10 medical confidentiality and nobody is talking about it.
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| 11 Incidentally, this thing does come under the purview of OSHA 12 as an industrial accident rather than under NRC as a nuclear 13 event.
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| D 14 There are four diesel fuel oil tank rooms in line 15 with corridors on each side of the row, and cross access at 16 the ends. The four deisel generators sit each on top of the r 17 associated tank room. Each tank room is about 30 feet high, 18 with single access door, with the door sill about 20 feet 19 above the tank room and adjacent corridor floor accesses by 20 ladder to a platform outside the normally closed door and j
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| 21 grating inside the door.
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| 22 Each door contains louvers which allow escape of air 23 displaced by incoming CO2 and prevent overpressurization of 24 the compartment by excessive CO2 injection such as was 4
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| c) 2. ..p.,,.n..d dur,ng th,s ...nt.
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| a
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| 7 1 When the CO2 injoction occurrod, the injoction was 2 intended to be automatically terminated on a time delay of i f
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| \
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| 3 about 72 seconds with release of between one and two tons. .
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| 4 Current information indicates that when the control system j 5 timed out and reset, it promptly reinitiated, and this 6 sequence occurred until the entire contents of the CO2 storage ,
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| 7 tank, which at that time was 10 tons in the 17-ton capacity l l
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| 8 tank, had been discharged, .
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| t 9 The Licensee believes that the problem is maybe in ;
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| 10 the system control panel, and the panel has been removed and !
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| t 11 sent to the manufacturer, Cardox, for evaluation. >
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| i !
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| 12 The subcommitee asked what peak pressure was reached 13 in the tank room. There is no installed pressure sensing and 14 recording equipment for the tank room, so the answer can only 15 be qualitative. CO2 is normally stored as a liquid at modest ,
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| I I 16 temperatures and pressures. When released, it promptly starts 17 to vaporize. But the latent vaporisation is applied by i
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| 18 subcooling to the point where it freezes. Subsequent ;
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| 19 sublimation as heat is absorbed from the environs, is 20 relatively slow, and apparently the escape area of the door 21 louvres was sufficient to prevent appreciable pressure buildup 22 in this plant design.
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| l 23 MR. BLAU: Excuse me, Jim. My name is Randy Blau, 24 I'm Senior Resident Inspector at Hope Creek. I have some 25 additional information that I got late yesterday,
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| ,_/
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| 8 i The Applicant did on injoction test in the room 2 this spring and they did measure the pressure. From the s
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| 3 pressure they got from a normal injection, they did 4 calculations that had not been reviewed but showed that --
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| 5 their calculations show that with the existing configuration, 6 a full tank dump in the room should have resulted in about 7 .6 pound of pressure in the room.
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| 8 Now, the' room is not in its final operations phase 9 configuration in that the area around the doors, around the 10 door frame has r.o t been sealed and will be sealed at a later 11 date. At that point, the only event path will be under the j
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| 12 door and a design opening around ventilation intake, which 13 closes automatically on CO2 but has a ventilation that has a 14 vent path around it.
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| 15 The previous information that there was a louvre in i
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| i 16 the door is not correct. In the operations phase, the 17 pressure from a full tank dump into the room would be worse 18 than the .6 calculated, and the Applicant has further 19 calculations necessary to make sure that the 20 overpressurization does not exceed NFPA requirements.
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| 21 MR. HENDERSON: Thank you, Randy. That's a big 22 help.
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| 23 An event similar to this event is reported to have 24 occurred at Grand Gulf on July 14, 1982. The protected volume l
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| 25 was the ECCS penetration room, and the room was tight enough
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| * -m.:
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| 9 1 so that a looked door was forced opon. At that timo the causo 2 was believed to be an internal and intermittent fall in the 3 actuation circuitry between the sensor and the control panel, 4 not in the control panel 5 The potential generic implications will be examined 6 after the evaluation of the Cardox efforts at Hope Creek.
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| 7 So there is, at least one historic event that looks 8 quite similar to this, and there is a possibility that there 9 is a defect in the generic Cardox design. We will know about 10 that later.
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| 11 I guess that is about all I have to say unless there 12 are questions.
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| l 13 MR. MOELLER: Several times the ACRS has written 1
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| 14 letters asking particularly about the potentiality for CO2 15 getting into a control room, you know, due to a release, and 16 AEOD about, what, three or four years ago extensively looked 17 at this and wrote a report on it. So my question is, is this 18 something that is peculiar to the fact that they are in the 19 construction phase? Had they been operating, would the 1
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| 20 sequence or the impact been different?
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| 21 MR. HENDERSON: Randy, can you speak to that? l 22 MR. BLAU: Yes. This event could happen in the i 23 operations phase. The dispersal of their carbon dioxide would i 1 24- not have been as great due to the fact that, for one, many 25 doors and construction cut-outs are still open in the plant
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| [
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| 10 l
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| 1 that would bo closod and aro, in fact, roquirod to closo
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| ,_ 2 during operation. In this event CO2 got throughout the U 3 54-foot elevation of the entire diesel area wing and the 4 adjacent radwaste building.
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| 5 As I said, during operations, the extent of it would 6 not be quite as great due to the doors open and additionally 4
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| 7 due to the ventilation system. The ventilation system at Hope B Creek has not yet been completed and, in fact, not balanced 9 yet, and during this event, the normal ventilation system was 10 not operating. So during operations, we would expect the event 11 to be different in CO2 dispersal, 12 I have not done a detailed review of the control 13 room ventilation system, but the design of the FSAR calls for 14 separate outside supply with redundant fan, safety related.
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| 15 That provides a slight positive pressure in the control room 16 with passive exhaust atmosphere with safety-related dampers in 17 the exhaust.
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| 18 MR. MOELLER: But you have the redundant intakes, 19 but does the control room have a CO2 monitor?
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| 20 MR. BLAU: As far as I know, the control room does 21 not have a CO2 monitor.
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| 4 22 MR. MOELLER: Which is another question, which is 23 off the subject, but does the control room have even a 24 radiation monitor?
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| 25 MR. BLAU: The control room has radiation ;
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| l
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| 11 1 annitors. Those havo not boon insta11od yet, but tho fg 2 ventilation system shifts to a filtered ventilation system on j
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| U 3 intake.
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| 4 MR. MOELLER: It has monitors on the air intake, but 5 my question was, is there a radiation monitor within the 6 control room, meaning for external dose?
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| 7 MR. BLAU: There is an area radiation monitor 8 measuring gamma dose rate in the control room, but there is 9 not an airborne monitor measuring, to my knowledge, the 10 quality of the air in the control room.
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| 11 MR. MOELLER: Thank you.
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| 12 MR. EBERSOLE: Are there any rooms which have 13 critical safety equipment which upon malfunction of the 14 distributing or apportioning systems would be mechanically 15 damaged, not provided with relief panels or what other means 16 that you have to do, to grant malfunctions and failures in 17 this apportioning system? Remembering, again, the 18 apportioning system is nonseismic and may do anything, in j
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| 19 fact, under the seismic system.
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| 1 20 MR. BLAU: Right. The apportioning system is 21 nonseismic, nonsafety grade. It serves nine rooms, the four 22 diesel fuel base, the four diesel rooms, and a control i 23 equipment messanine below the control room. The Applicant has 24 an engineering review that is going on. I'm sorry I can't i
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| 25 really answer your question. The Applicant now feels they can
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| ( -
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| 12 1 provo that thoro won't be nochenical demago, but I can't
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| ,_s 2 comment further on that.
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| I f\ ') 3 MR. WYLIE: I just wanted to ask a question. I 4 understood you to say they had automatic louvres in the 5 pressurized room. They were olosed on the ventilating system.
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| 6 MR. BLAU: The ventilation system of all CO2 oiro 7 rooms has CO2 fire dampers, which are combination fire dampers 8 which close on a heat signal, not a signal, melting of fusable 9 links. Also, when the CO2 activates, it sends an electrical 10 signal to the damper that fuses the link and allows the spring 11 to close the damper.
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| 12 MR. WYLIE: That bottles up the room.
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| }
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| 13 MR. BLAU: Those are fire protection dampers which 1
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| 14 have a fire barrier rating. They are not air-tight dampers.
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| 15 In other words, you would expect trace amounts of carbon 16 dioxide to escape through the dampers.
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| 17 MR. WYLIE: Okay. Do they design for pressure 18 reliefs in the room?
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| 19 MR. BLAU: These rooms do not have rupture discs or 20 other formal reliefs.
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| 21 MR. WYLIE: A flapper is all you need someplace 22 high.
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| 23 MR. BLAU: Right. The overpressure calculations 24 involve calculating the vent area, the available vent area. I l
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| i 25 don't know if there is anyone here --
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| }
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| 1 i
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| i l i
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| .I
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| 13 4
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| 1 MR. WYLIE: I undoratood they would havo gotton 2 .6 pound the way it is right now, but once sealed, you are 3 going to get much higher than that. If you assume one pound, 4 that is 144 pounds per square foot.
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| 5 MR. HENDERSON: I think any more on this particular 6 area would be pure speculation.
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| 7 MR. MICHELSON: I need clarification before you out 8 off the subject. The other day you told us CO2 got into the 9 diesel room itself. I'm wondering if you can confirm --
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| 10 MR. EBERSOLE: He said it is the diesel room.
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| ; 11 MR. MICHELSON: It is the tank room.
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| i 12 MR. BLAU: It was the tank room below, which is in 13 the basement, at elevation 54.
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| j 14 MR. MICHELSON: The clarification I need, did any of l
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| 15 it get into the diesel room?
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| 16 MR. BLAU: They did not detect any -- the safety 17 efforts involved people in air masks looking for unconscious 18 people. They all had portable oxygen monitors which alarmed at 19 19.5 percent and decreasing. The only alarms received by any 4
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| 20 of the rescue people were on the 54-foot elevation of the 3 21 building, two floors below the diesel building, which is on 22 elevation 102.
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| I 23 MR. MICHELSON: Okay.
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| 24 MR. LEWIS: I'm just way behind my colleagues. I'm 25 still trying to understand the safety significance of this i
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| +
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| 14 1 plant to the plant if the plant had boon in oporation. Is tho 2 safety significance that CO2 might have gotten to the control
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| '\ 3 room and adversely affected the operators, or is there another 1 4 safety significance I missed?
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| I 5 MR. MICHELSON: The real problem might have been the 6 same problem with the CO2 control panel. If the actual 7 inadvertent actuation had been in the room below the control 8 room and they had dumped ten tons into there, it might have 9 been a very interesting safety significance.
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| j 10 MR. LEWIS: So the safety significance is that it i
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| 11 could have happened elsewhere in the plant.
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| f i
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| 12 MR. MICHELSON: That's the real problem, in my mind.
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| I 13 MR. WYLIE: As I understand the system, it serves j 14 many areas, including the area under the control room, as was 15 outlined a while ago.
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| 16 MR. BLAU: That's correct.
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| 17 MR. MOELLER: How much CO2 would it take to shut the 18 diesels down on the air intake?
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| i
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| { 19 MR. LEWIS: It doesn't mean they were simultaneous.
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| 20 MR. MOELLER: The diesels need oxygen.
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| 21 MR. EBERSOLE: They operate from outdoors. They 22 didn't have CO2 in the combustion chambers. They may see CO2 l
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| 1 23 in the cooling environment of the generators if they are CO2 i,
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| i 24 protected in the engine rooms. In that case, they close up l 25 and lose their generator cooling.
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| l l
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| 15 1 MR. HENDERSON: Tho prosumption is if you dischargo 2 the CO2 to the engine room itself, at that engine, that i
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| a Q 3 diesel generator is an operator, but the combustion area 4 intake is from outside.
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| 5 MR. MICHELSON: The other safety significance, of 6 course, is the seismic qualification of the Cardox panels It t
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| 7 isn't qualified, so one wonders during an earthquake do you 8 expect ten tons of CO2 to be released here, there or 9 everywhere. It's a concern any time you get an inadvertent 4
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| +
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| 10 actuation.
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| 11 MR. WARD: The risk is that person will be disabled?
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| 12 MR. MICHELSON: I don't think there is any 13 mechanical risk. I assume there were prudent designers and i 14 designed for the dump of the full capacity of the system 15 anywhere. If they haven't, they have got to go do their J
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| 16 homework.
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| l ,
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| a 17 MR. EBERSOLE: They do not do this. Even TVA --
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| 18 MR. MICHELSON: I don't know that they do or they 19 don't, Jesse. I know TVA blew some rooms over there.
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| 20 MR. WYLIE: My experience goes back many years with 21 hydro units where they always used CO2 for extinguishing fires 22 in generators, but they always have pressure release. Very 23 simple pressure release higher in the machine to make sure you
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| ; 24 don't overpressure the machine when you shookt them.
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| l 25 Generally those are multi-bottle types installation.
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| 0
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| 16 1 Tho first shot in cno shot, ono or two bottlos, and 2 then you have an orifice release to the rest of the bottles, i
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| \
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| 3 Bet now these are bulk systems and they are relying strictly ;
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| I 4 on electrical controls to release the timed release. So it's j t
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| 5 a different application.
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| I l
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| 6 MR. NICHELSON: I assume there are blowout panels ,
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| 7 for it. I don't know that for a fact. f i
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| 8 MR. WYLIE: All it does is lift a flapper.
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| 9 MR. WARD: Mr. Rossi, we have got a variety of j 10 opinions from the committee on the safety significance.
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| I 11 MR. ROSSI: I think the safety significance clearly i 12 in these kinds of things is the inadvertent actuation of any ,
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| i 13 fire system that may interfere in any way with either !
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| 14 personnel or with equipment. }
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| i i t
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| 15 1 think Ron Hernon wanted to say a couple of words. j l
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| 1
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| , 16 MR. HERNON: Ron Hernon with NRR, [
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| 1
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| * I 17 A piece of information we didn't have for the i l
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| 18 subcommittee the other day was that there was a generic issue !
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| 19 that is presently being prioritized by Nuclear Reactor i
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| ! l l
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| ; 20 Regulation. It's Generic Issue 57, and we would expect the i
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| 21 prioritisation to be completed within the next month or two. l t
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| I 22 Inadvertent actuation of fire protection systems.
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| 23 MR. ROSSI: I think the safety significance that i
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| 24 they will be looking at is whether the inadvertent actuation !
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| 4 4
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| i j 25 of fire suppression systems, period, whatever they may be, can !
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| f 1 <
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| l
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| 17 1 interfere with either equipment or personnel and therefore
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| ] 2 affect the safety of the plant. The generic issue would be to 3 determine whether that should be looked at generically across 4 the board in terms of looking to see if what is being done 5 today is adequate or not.
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| 6 MR. LEWIS: You understand what's troubling me. I'm 7 trying to separate the regulatory significance from the safety 8 significance, and as I understand it, the issue of the safety I 9 significance, at least having heard the differwnt opinions of 10 my friends and colleagues, is not yet entirely clear. There +
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| i 11 are several things that could have happened, if this had (a) f i
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| 12 happened in another place, if it happened in conjunction with 13 an earthquake, as Carl said, or other ways that haven't really
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| \ 14 been thought through yet.
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| 15 Is that really the situation, that there is some 16 potential safety significance, but nobody is quite clear 17 exactly yet what the most serious issue ist 18 MR. ROSSI. Or to what extent it exists and how I 19 probable it is, and that would be what the generic issue would 20 address, precisely that. '
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| 21 MR. LEWIS: That's what I was concerned about i 22 Fine.
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| 23 MR. MOELLER. Is the generic issue only for CO-2, or 24 does it include watert 1 25 MR. HERNON: It includes CO-2 and water.
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| 1
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| . = . _ _ _ _ . _ . _ _ _ _ _ __ __ _ _ . _ _
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| 18 1 MR. CARD: Chot about holen, for oxcmplo, is it i
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| 2 general?
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| 3 MR. HERNON: It's general.
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| 4 MR. EBERSOLE: Any further questions?
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| l 5 LNo response.3 6 MR. ROSSI: Jim Henderson is also going to discuss
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| ) 7 an event that occurred in July at Turkey Point Unit 3, i
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| s j 8 involving the auxiliary feedwater pumps at that plant, and
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| ; 9 that will be followed by another event which the subcommittee i
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| I 10 considers to be somewhat closely related to on Turkey Point.
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| l 11 Go ahead, Jim.
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| 12 MR. EBERSOLE: ! think this presentation has as a 13 sort of a predecessor the Davis-Besse case. We find we have I
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| i 14 another plant which is borderline Davis-Besse.
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| 15 (Slide.3 16 MR. HENDERSON: I think it is rather interesting 17 that the Turkey Point came along not that long after 18 Davis-Besse, and there is a similarity, although there are
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| ) 19 some significant differences, too.
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| I 20 Last Tuesday I presented the subcommittee a 21 discussion of the event of July 21-22 Turkey Point. Unit 3.
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| 22 Although ! couldn't answer all the questions, a decision was 23 made to present this to the Full Committee.
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| l 24 I have attempted to acquire answers to the i
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| 25 subcommittee questions and in that process have had telephone l
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| l
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| 19 1 ocnvorcoticno with reprocentativos cf tho Lioonsoo, on wall as 2 the Staff.
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| O 3 This has resulted in acquisition of some conflicting 4 information which I have not been able to completely resolve.
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| 5 Some of the chronology of events is aven in the 6 characterisation, such as low us. high steam generator level, 7 are not entirely clear. I believe that these ambiguities do 8 not affect the overall validity of the presentation.
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| 9 For example, as will be explained more fully later, 10 the Licensee challenges my characterisation of all three 11 auxiliary feed pumps as inoperable. I got some volunteer help 12 yesterday that I could have gotten along. I think, better 13 without. It must be understood that I was not directly and 14 personally involved in the event, and all that I report may be 15 properly considered to be hearsay, although I believe it to be 16 the truth as it was related to me.
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| 17 So now let me go on with this, with the event.
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| 18 On the evening of July 21, 1985, both Turkey Point 19 Units 3 and 4 were operating at 100 percent power. At 11:41 20 p.m., Unit 3 tripped off line. Unit 4 was unaffected. The 21 Licensee attributes the trip to electronic noise generated by 22 a lightning strike.
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| 23 Unit 3 has two half-size electrio drive feed pumps.
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| 24 These pumps have constant speed drives and regulate feedwater .
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| 25 flow by flow control valves.
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| | |
| 20 1 Initially tho fisw ocntrol valvos cated to roduco 2 flow and the feedwater pumps remained at service supplying 3 water for post-trip heat removal 4 However, this rapid flow reduction was not easy to 5 control, and two minutes after the unit tripped, the feedwater 6 pumps tripped on steam generator signal.
| |
| 7 It is not clear whether the steam generator level 4 condition was too high or too low. The main feed pump trip 9 generated an auxiliary feedwater pump start signal. All three i
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| 10 auxiliary feed pumps started automatically and performed as 11 designed.
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| 12 The unit was stabilised and preparations were made i 13 to restart the unit.
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| I 4
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| j 14 The main feed pump reportedly was started at 11:50
| |
| ' 15 p.m., and at about 11:58, steps were initiated to return the !
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| i 16 auxiliary feed pumps to standby condition. i i 17 The A and C pumps, which comprise one train, were
| |
| { 18 placed in standby condition without apparent difficulty.
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| I j 19 Problems were experienced with flow control valves for the j 20 feed pump and troubleshooting was initiated.
| |
| 21 The flow control valve reportedly would not respond i
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| 22 to automatic or manual position signals. It was stuck in an
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| . 23 open position.
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| l
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| ' 24 At about 4:05 a.m., while feedwater flow and steam 25 generator level were being controlled by both flow valves on i
| |
| | |
| 21 1 tho unin foodwator system and troublochooting en tho B pump 2 was still in progress, a high level steam generator trip 3 occurred.
| |
| 4 All three auxiliary feed pumps started 5 automatically. The A and C pumps apparently were placed in 6 standby without difficulty, promptly tripped and on mechanical 7 looked out overspeed trip.
| |
| 8 The B feed pump, which had been placed in an 9 abnormal configuration for troubleshooting, started more 10 slowly and the speed was controlled by an electronto overspeed 11 element.
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| 12 Mechanical overspeed devices.
| |
| 13 The Five-All type, which trips the steam stop valve 14 and must be manually locally reset. The electronic overspeed 15 sensing device acts on the hydraulio governor to reduce speed 16 to a lower speed setpoint where it returns control to the 17 hydraulic for reasons I don't fully understand.
| |
| 18 The governor allowed the turbine to again overspeed 19 to be intercepted by the overspeed sensing device, and the 20 turbine pump was cycled on about a three-to-five second 21 period.
| |
| 22 The flow regulating valve was stuck and closed. The 23 steam generator fluctuated with the pump C. However, the 24 steam generator water was being supplied to the steam 25 generator and the quibble between me and the Licensee is i
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| i l
| |
| (
| |
| l
| |
| | |
| 22 1 whother boccuco it was not subjoet to oithor cutomatio or ,
| |
| 2 manual control, it was operable or not.
| |
| 3 During the telephone call yesterday afternoon, the i
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| 4 Licensee representative objected to my position that the B ;
| |
| 5 feed pump was knoperable.
| |
| 6 MR. WARD: You mean, Jim, the pump was running and I
| |
| 7 supplying water, but it wasn't controlling -- l 8 MR. HENDERSON: It was running and supplying water 9 on the cycito basis, and it was restoring low steam generator i
| |
| 10 level on the sort of a ratchet basis. It did bring the steam 11 generator level within normal limits.
| |
| 12 WR. ROSSI: Dan Mcdonald from NRR would like to add 13 something here.
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| i
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| } ,, 14 MR. MC DONALD: I am Dan Mcdonald, Project Manager i
| |
| 15 for Turkey Point.
| |
| 16 In discussions with both the resident and the 17 Licensee, the steam generator, it was the C steam generator '
| |
| 18 that had the open valve, and the second event was a low-low a
| |
| 19 level in the B steam generator, which initiated the actuation l 20 of aux feedwater, and during the event, even though at the 21 control room the indication was erratic for the B pump, the 22 rpm was constant, which was observed down at the auxiliary l 23 feed pumps, and the Licensee indicates the water level was 24 recovering in the B steam generator. And the fa!!ure of the l
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| l 25 flow control valve to the C steam generator did not allow for i
| |
| | |
| 23 1 the aux feedwater to get to the C steam generator. But the 2 main feed was still feeding the C generator.
| |
| 3 They did within about five minutes get the A feed 4 pump operable and were feeding feedwater via train number one 5 to the C generator.
| |
| 6 MR. EBERSOLE: Let me comment at this point and ask 7 you to verify all of these pumps are turbine-driven.
| |
| 8 MR. MC DONALD: Yes, sir.
| |
| 9 MR. EBERSOLE: You mentioned a stuck valve. What to valve was that?
| |
| 11 MR. MC DONALD: It was a flow control valve to the C 12 steam generator.
| |
| 13 MR. EDERSOLE: The predominant habit of safety 14 reliefs sticking open, everybody knows about that, and here 15 you will subsequently hear that the isolation valves between 16 steam generators in this case cannot close under certain 17 conditions.
| |
| 18 MR. HENDERSON: I think there is a misunderstanding 19 there. As on the main feedwater system, the pumps run at 20 constant speed. The control of flow to the steam generator is 21 by a flow regulating valve in the pump discharge, and there is 22 no overpressure protection involved in this. But the flow 23 regulating valve has a pneumatic actuator, and that was where 24 --
| |
| 25 MR. ROSSI. I think your concern is if you get a
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| (
| |
| | |
| 24
| |
| ; 1 otuok-opon sofoty volvo, you wnuld loso the stoca --
| |
| 2 MR. EBERSOLE: Driving it to all pumps. Because you 3 will subsequently hear the isolation valves don't work between 4 steam generators.
| |
| 5 MR. ROSS!' 1 understand your concern. I would like 6 to point out a couple of things. On this plant, it is not 7 typical to lift the cold safety valves on a trip. In some B&W 8 plants that occurs fairly frequently. So that's the i 9 difference.
| |
| , 10 Another difference between this plant and let's say j 11 Davis-Besse is that this plant has considerably more inventory 12 in the steam generators than does a plant like Davis-Besse.
| |
| 13 Another thing -- I'll ask Dan Mcdonald to tell you r
| |
| i 14 in just a minute about the electrio-driven start-up pumps that 15 are available at the plant, and although they are not
| |
| ! 16 safety-related, certainly signiftoantly increase the L
| |
| 17 reliability of having feedwater for the more credible kinds of 18 events like trips to the plant, losses of main feed and that 19 kind of thing, 20 Let me say one other thing before I turn it back 21 over to the people that are supposed to be talking about it.
| |
| 22 On the safety significance of an event like this, ,
| |
| 23 let me address that just a minute. We have got three turbine '
| |
| i I 24 driven auxiliary feedwater pumps. We design plants for the !
| |
| 25 single failure ortteria, and when we see problems with j I i
| |
| | |
| l 25 i
| |
| 1 tultiplo rodundant coupsnonto in a system, w3 got concornod.
| |
| 4 i
| |
| 2 MR. LEWIS: I agree with you.
| |
| . 3 MR. ROSSI. We are particularly sensitive at this 4 point in time obviously to problems with turbine-driven 5 auxiliary feedwater pumps. That might indicate common mode i
| |
| 1 6 failure.
| |
| I 7 So this whole area is being looked at quite 8 carefully from the standpoint of things that we can make the ,
| |
| 9 industry aware of, or we can ask the industry to do, to try to 10 eliminate any kind of common mode failure elements in these i
| |
| 11 kinds of events.
| |
| 12 That's the safety significance of this one, that 13 there were problems and you can argue about how inoperable the 14 system was or was not, but there were problems with the 15 redundant portions of the system, and that is something that I 16 concerns us, and we are sti,11 looking at this event, and i
| |
| obviously we are sil11 looking at the problems 17 --
| |
| i 18 MR. WARD: I don't think you have to convince us of ,
| |
| t 19 this one. Even the committee understands this one, i
| |
| 20 MR. LEWIS: But therefore it would be nice to go a 21 !!ttle bit deeper into why the A and C tripped on overspeed 22 instead of arguing about whether ratcheting was an l l 23 inoperability on the 3 pump, 24 MR. ROSSI: I agree with you. I don't know whether i
| |
| 25 you have any more to add on the cause, but this one has i
| |
| [
| |
| | |
| 26 1 centinuod -- in going to bo continuod to ho Icekod ot.
| |
| 2 MR. EBERSOLE: One small comment before we get into O 3 the mainstream again. This is Turkey Point. It's in 4 hurricane country, and the scenario, the pall that hangs over 5 it, it may experience an ACL power outage for a very long 6 period of time. In that case, these two units --
| |
| 7 MR. ROSSI. That is correct. Those are the 8 safety-related pumps.
| |
| 9 I think it is worthwhile describing the electrio 10 ones.
| |
| 11 MR. WARD: This is a point that I don't think has 12 come out, that there are three aux feed pumps, 100 percent 13 capacity, but they serve both units.
| |
| 14 MR. EBERSOLE: That is right.
| |
| 15 MR. WARD: And there's a lot -- apparently the 16 design of this plant, there's a lot of shared equipment 17 between the two units.
| |
| 14 MR. HENDERSON: That's true. It seems to me it's 19 more than has typtoally been allowed by the Staff.
| |
| 20 MR. LEWIS: And two of those three failed.
| |
| 21 MR. MC DONALD: Gentlemen, if you'd like, I can 22 deserthe at least what they believe was the cause of the 23 overspeed and mechantoal trip on the A and C pump. There's a 24 steam inlet valve on the trip and throttle valve. When you 25 reset the system, you are to open the trip and throttle valve,
| |
| | |
| . - - .. -_ - - .= -
| |
| 27 1 ond then closo tho otocm inlot valvo. Chon tho pumps roll 2 dead, then they go down and operate the knob on the governor, 1 \
| |
| 3 which allows a piston to move up and dump the oil that's in 4 the governor.
| |
| 5 There's another orifice, but it's very small and it 6 takes, I believe, on the order of about 30 minutes to drain.
| |
| 7 What they believe happened on that night when they 8 were down troubleshooting on the B pump and the C flow control j 9 valve on the C steam generator, that the operator in the
| |
| ; 10 control room noted that the trip and throttle valve had been 11 left closed and not opened, according to procedure, which 12 trapped steam between the steam inlet and the throttle valve.
| |
| i j 13 When he opened that valve, it caused the turbines to 14 roll, which pumped ott back into the governor. Then when they
| |
| }
| |
| l
| |
| } 15 got the signal in a short time, the second initiating signal, a
| |
| l 16 there was already oil in the governor that caused the 17 overspeed. They believe that's the case.
| |
| I 18 MR. ROSSI: I would like to say something else about I i 19 an event where it is my understanding the problem was after r
| |
| 20 the trip, after the pumps had gone a while and when they had 21 been shut down and restarted. That's correct, tan't it?
| |
| 22 MR. MC DONALD: Yes.
| |
| 23 MR. ROSSI: I'd Itke to point out after these plants 24 are down for a while, the decay heat level and the stored
| |
| , 25 energy and so forth in the reactor coolant system, a lot of N
| |
| | |
| . -_ . - . -- - - - - - - - . . ~ . _ - _ _ . _ - .-. .- w_ . -. - _ - - .- ~
| |
| 28 1 that in Cush, much Icwor. So thoro is scmo additional margin
| |
| . 2 for getting these things restarted, you know, when you're l l l
| |
| ! 3 . essentially at hot standby and you have problems. j 4,
| |
| 4 Nonetheless, I think we all understand the ;
| |
| S signittoanoe of it, and it is going to be continue to be t
| |
| i 6 looked at in terms of possible generio implications to 7 eliminate common mode failures.
| |
| 8 MR. MICHELSON: A couple of questions.
| |
| l 9 The first one on auxiliary feedwater for pressurised I
| |
| i 10 water reactors. ;
| |
| 11 Does the Staff consider it acceptable to have to i i
| |
| j 12 reset the turbine from the local position?
| |
| I i
| |
| I 13 MR. MCDONALD: Normally they are automatto reset, I r
| |
| 14 understand, on turbines used on BWR designs. In this case it i.
| |
| 15 was accepted by the Staff.
| |
| 16 MR. MICHELSON: I'm asking pressurised water now, l 17 not boiling. I i
| |
| 14 MR. MCDONALD: I appreolate that. I'm not sure at 19 the time the evaluation was done that it required a local l l k0 reset; however, the Licensee has, I believe, some 16 different '
| |
| t 21 actions that they are taking related to aux feedwater. One of l I !
| |
| j 22 them is going to put an automatto dump in the oil system for 23 the governor so it will not require local reset.
| |
| j 24 MR. MICHELSON: That leaves the second question.
| |
| t i 25 0.E. had these kinds of problems with overspeed for a couple I
| |
| k i
| |
| (
| |
| -v.., __,, .-~.-- _-.-.~.._m._ . . , . - - -
| |
| -,m.7 _.,_.-,_._mv,-m_,m.- ,,,-..,.,-..,.w .,.,--..m-,...e,_.,_.-.,,..m.
| |
| | |
| i
| |
| ! 29 i
| |
| i 1 of yoars and finally workod out seus good solutinne and don't 2 have any move overspeed problems. Don't those good solutions i
| |
| O 3 somehow get over to the pressurised water folks?
| |
| 4 MR. MCDONALD: I believe the modification with the 3
| |
| 5 governor and high pressure steam inlet for the turbine drive 6 was fairly recent as a result of the TMI modifications on aux 7 feedwater. .
| |
| j j e MR. MICHELSON: With G.E. they solved this thing a l
| |
| ; 9 year or two ago. Is it now required that the pressurised
| |
| ! [
| |
| ! 10 water people go and put these fixes on that G.E. learned how !
| |
| }
| |
| ! 11 to do? .
| |
| i l 12 MR. MCDONALD: 1*m not aware of any requirement, i 13 MR. MICHELSON: Isn't there something funny about
| |
| ! 14 our regulatory process that is a barrier between these two ,
| |
| t .-
| |
| i
| |
| ! 1S types?
| |
| l 16 MR. ESERSOLE: That fix has not yet got to OESSAR l ;
| |
| 17 !!.
| |
| I i 18 MR. MICHELSON: No, no, Jesse. The GESSAR !!
| |
| l i ;
| |
| j 19 people, that's different. They said it was fixed. Remember,
| |
| ) 20 I asked the question. [
| |
| ]
| |
| ] 21 MR. EBERSOLE: The narrative states otherwise, i !
| |
| 22 MR. BEARD; Carl, maybe I can help you on this one.
| |
| :l
| |
| ; 23 As you know, I was one of the guys that was up to " Messy" i
| |
| j 24 Davis. They had turbine troubles. Part of the solution 25 seemed to reside in areas that the border people had already !
| |
| l
| |
| , i i
| |
| i
| |
| | |
| 30 1 addrossod. Ono of tho thingo wo triod to point cut to thcm 2 was there was a post-TMI requirement that each utility develop 7_
| |
| 3 a system for reviewing operating experiences at their plants 4 and at other plants. I forget exactly the title and the 5 reference number, but that's not important.
| |
| i j e MR. MICHELSON: I recall l
| |
| 7 MR. BEARD: One of the things, I believe, that NRR 8 is retooking at a result of the " Messy" Davis event is are the 9 utilities really reviewing operating experience at other 10 plants to the full capability they should because the very
| |
| ; 11 thing that you pointed out we pointed out to them, that the .
| |
| 1 l 12 Terry Turbine folks and the Limitor Works and Woodward 13 governor folks have already worked extensively in this area on 14 these turbines.
| |
| ).
| |
| 15 So I suspect personally that there will be a lot of 16 improvements and a lot of a,ttention brought to PWRs reviewing j 17 operating experience on botters wnere it is related 1
| |
| i 18 equipment. But obviously, I can't speak for Mr. Denton, but I l
| |
| l 19 personally expect he will in that area.
| |
| 20 MR. MICHELSON: Apparent 1/ tt was lucky in this case l l
| |
| 21 somehow, ! guess.
| |
| 22 MR. R05G1. I would 1the to suggest unless somebody 23 has some additional questions or Jim has something --
| |
| 24 MR. LEWIS: I wanted to say one word in support of i
| |
| ' i 25 Carl's concern. Viewed superfietally, this appears to be an (o}
| |
| r
| |
| | |
| 31 1 ovont which morits a sonno of clarm. U0 havo got a triply f-s 2 redundant safety system which sort of worked one-half; that 3 is, 2-1/2 parts of it failed in the sense that the third pump i 4 was working but was not entirely controllable in the sense --
| |
| 5 that would seem to me to be a cause for a kind of high 6 priority alarm and concern on the part of the Staff.
| |
| f 7 I wonder if it is.
| |
| 8 MR. ROSSI: As a measure of our level of concern, we 9 pick out the events that we think are significant to come down 10 and tell you about. This is on our list. We are concerned 11 about it Davis Desse has highlighted the general problem of 12 common mode failures and problems with turbine-driven pumps.
| |
| 13 I think at this point in time I would say there is a 14 considerable amount of alarm on these kinds of issues.
| |
| 15 MR. LEWIS: I understand that you understand it, but 16 if I were an antinuclear outsider, I would Le screaming "Why 17 don't you shut down these plantst Your safety system isn't 18 reliable, primary safety system."
| |
| i 19 MR. REED: I think it is opportune to break in a 20 little bit with philosophy and get farther above the nuts and 21 bolts tesue, which ! see someone has recommended that we work 22 above. Mr. Rossi has just recommended or tried to bring us at 23 an intermediate plateau above nuts and bolts in talking about 24 components that are almilar in a one-principle system, 25 auxiliary feedwater, for the removal of decay heat.
| |
| l .__ ____-__________-_ _ _ .
| |
| | |
| 32 1 New, what hasn't boon acid and wasn't brought boforo 2 the subcommittee is that there were two other auxiliary O 3 feedwater system failures in the last two months, I believe i 4 one at Salem and one at Smud, another B&W. The interesting i
| |
| S thing to me, and what should be interesting to ACRS, is that 6 auxiliary feedwater on some PWRs seems to get into problems, j I
| |
| 7 and perhaps auxiliary feedwater from an ACES viewpoint should '-
| |
| 8 be looked at very hard as to whether or not that single decay i f
| |
| 9 heat route or path is adequate in the long run for some PWRs. !
| |
| I 10 MR. WARD: Mr. Wylie.
| |
| 11 MR. WYLIE: I just had one observation. It's [
| |
| l i
| |
| 12 interesting to note, both here and " Messy" Davis and Turkey i 1
| |
| 13 Point, that the equipment that was assured safety was l t
| |
| 4 14 nonsafety related.
| |
| I 15 MR. ROSSI That is a point. We certainly cannot 16 cross out the importane of the nonsafety-related equipment j 17 that is on these plants, !
| |
| 18 MR. WYLIE: The reason I make that observation is I l
| |
| I 3 19 there seems to be a trend that if it's not safety-related, you l
| |
| I 20 discount it, you don't use it, I think we can learn something l
| |
| \ l j 21 out of that, l
| |
| 22 M R ,. ROSS!: I think we have covered the main aspects l i
| |
| 23 of everything we had to say, and I would suggest that we go on f
| |
| 24 to discussion of the MG!V failure at Turkey Point unless '
| |
| i
| |
| ; 2S anyone has an objection, i s l I I
| |
| i t t
| |
| | |
| 33 1 MR. EBERSOLE: Thic is on intorrotated mottor cinco
| |
| - 2 this provides a means to commonly bleed down all steam 3 generators and thus lose the driving head for the turbine 4 points. Same plant.
| |
| I 5 MR. ROSSI: For this one we will have Vern Hodge of i 6 the Office of Inspection and Enforcement discuss the MSIV 7 problem at Turkey Point.
| |
| 8 MR. EBERSOLE: While he is getting geared up, let me 9 ocament. John McAvoy make a study of all the aux feed pump 10 configurations, and may plants have just two pumps. Most of 11 them have an electric pump and a turbine pump, so by no means 12 to all of them have three pumps, two motor and one turbine.
| |
| 4 13 MR. LEWIS: Three don't seem to do you much good 14 when they all fall. I would view this with great alarm.
| |
| 15 MR. EBERSOLE: This is a critical safety system.
| |
| 1 16 MR. LEWIS: I would hate to see it shoveted into a I
| |
| ;l 17 generic study that would last three years. There seems to be ;
| |
| i i le a real emergency.
| |
| j 19 MR. ESERSOLE: There appears to be much more reason 20 to shut a plant down for this reason because it supports LOCAs 21 under the steam generator for supports. Plants have been shut 22 down for far less important reasons.
| |
| 23 MR. HODOE: Good morning. I'm Vern Hodge from IE.
| |
| 24 In July NHC received a Part 21 report from Turkey l 25 Point units about the potential for the MSIVs to fait closed
| |
| | |
| 34 1 undor Icw stoca flew canditions.
| |
| 2 MR. EBERSOLE: To fail open.
| |
| ; 3 MR. HODOE: They would not close.
| |
| 4 MR. EBERSOLE: Yes. You said fait closed.
| |
| 5 MR. HODGE: Failed to close. Sorry, i
| |
| 6 So two issues can be discussed here. One is the 7 Licensee's review disclosed unanalysed condition possible for 4-8 the main steam line break accident. The NRC inspectors 9 observed inadequate testing practice.
| |
| J 10 CS11de.2 11 This diagram shows roughly how the valve works.
| |
| 12 Instrument air is fed through two accumulators to a I 13 piston-operating cylinder which moves the shaft up or down to
| |
| ! 14 olose or open the MS!V. Essentially this problem occurred --
| |
| i 15 also, to assist the closure, partial engagement spring. This l 16 starts the piston down. It's used mostly for testing t
| |
| I 17 purposes. And then assisting the valve closure is steam flow i
| |
| 18 in the steam line. 7 i
| |
| 19 Under low steam flow conditions, that is absent, of 3 20 course, and the problem then essentially is because the 21 accumulators are too small.
| |
| 22 MR. MICHELSON: That's not what you would call a i
| |
| ! 23 fait safe design, safe meaning, I assume, full closure. A f i 24 failure of air supply, for instance, it doesn't fail ,
| |
| e 25 closed. Acoumulator air supply. ,
| |
| I
| |
| +
| |
| i 1
| |
| a
| |
| | |
| - . - -- _. .-.. --. _. . _ ~. . -- . . _ _ _
| |
| . 35 1 M2. HODOE: I think it's a mattor of scalo. It's
| |
| - 2 designed to close.
| |
| 3 MR. MICHELSON: If it's designed right, it will 4 4 close.
| |
| 4
| |
| ; 5 MR. HODGE: Right.
| |
| i i
| |
| 6 LS11de.3 7 For the main steam line break accidents, you see ,
| |
| l 8 MSIVs won't close. Testing program has indicated that, j 9 indeed, they won't close under some conditions. The problem to applies to the Turkey Point and the Robinson plants, and the
| |
| , 11 problem is that a threshold steam flow is required for the 12 valves to close. This is not known exactly, so for ,
| |
| I f 13 conservatism, Licensee assumes they exceed the aux feedwater I
| |
| 14 capability to make up so continued blowdown is possible.
| |
| I 15 MR. WARD: What is the line siset 16 MR. HODGE: I'm not sure. I think it's about 28 i t l 17 inches. >
| |
| 1 18 MR. WARD: Okay.
| |
| 19 CS11de.3 20 Licensee justifies continued operation by 21 establishing backup systems to assure the availability of ,
| |
| 4 1
| |
| 22 instrument air. Diesel air pressure would backup the plant a
| |
| i 23 system. Cross-ties have been arranged from the fossil plant >
| |
| 24 instrument system, and a procedure has been instituted to shut 25 down the plant if the instrument air supply does fail,
| |
| __-,m--., , , _ , , _4 ,.-...-.- . ,,.._-s,.__ . . _ - . _ . - _ _ _ , . _ . .-
| |
| .- . _ . _ _ . , - _ _ . ~ , . _ _ . - _ _ _ , _ r,_._ . . . _ . . _ . _ _ . ,
| |
| | |
| 36 1 I understand in previous operating oxperience this x 2 instrument air supply has not failed. Corrective action as to 3 change the design on an expedited basis to assure MSIV closure 4 in 5 seconds as required by the technical specifications 5 without steam flow assistance. At the same time, this design 6 modification would resolve the problem with the testing 7 practice alluded to earlier, which I will discuss now.
| |
| 8 CSlide.]
| |
| 1 9 In February, inspectors noted that the stroke 10 testing procedure did not call for securing instrument air 11 supply, and as a result, the Turkey Point and Robinson plants 12 were cited as violating 10 CFR 50.55A(g), which invokes the 1 13 ASME boiler and pressure vessel code, one paragraph of which N
| |
| 14 requires that testing of the valve, meaning observing the 15 behavior of the valve when the actuator power is secured and 16 NRC has determined that actuator power includes both electric 17 and instrument air power.
| |
| 18 We are not certain how many plants this would 19 effect. We are writing an information notice on it in the 20 hope that Licensees will review their testing practices and 21 understand the possibility of the unanalized condition.
| |
| 22 I would be happy to answer any questions.
| |
| 23 MR. MICHELSON: That test requirement pertains only 24 to Robinson and Turkey Point?
| |
| r 25 MR. HODGE: No, sir. This is a regulation.
| |
| | |
| 37 1 MR. MICHELSON: For all plants?
| |
| 2 MR. HODGE: I believe so.
| |
| C_Y 3 MR. REED: On the issue of why the valve didn't 4 close, I believe you said in subcommittee it was because 5 perhaps the calculated pressure force from the stem was not 6 taken into consideration well enough. Now, I don't understand 7 that not being taken into consideration, but generally the 8 thing that changes is packing friction. Is there a packing 9 friction aspect to this motion to close?
| |
| 10 MR. HODGE: Probably so, yes. In a diagram, the 11 unbalanced force from the steam pressure down here probably 12 would be eventually balanced by the air pressure up here as 13 depleted. All the terms and equations become small; therefore, I
| |
| gj 14 the pressure it can stand is what is left within the 15 enclosure.
| |
| 16 MR. REED: That should have been calculated by the 17 designer, but he should have also put in there a healthy 18 margin for packing friction and packing condition.
| |
| 19 MR. HODGE: Undoubtedly that is true.
| |
| 20 MR. REED: After all is said and done, you will be 21 looking at the final balance here to find out what pressures 22 are required in the top of the cylinder to cause this closure, 23 and you will find out whether the packing was, let's say, not 24 properly maintained, whether the design was in error.
| |
| 3 25 MR. EBERSOLE: If there were a relatively small main r
| |
| \_)
| |
| | |
| 1 38 l 1 steam lino brook, procumably thoro would be a fairly slow 2 blowdown, and that might not close, I presume.
| |
| O 3 MR. HODGE: That's correct.
| |
| 4 MR. EBERSOLE: Would that lead to containment I
| |
| 5 overpressurization because you would dump the contents of both i 6 steam generators into one volume?
| |
| 7 MR. ROSSI: I believe that would take another 8 failure of the check valve if it were a break inside the 9 containment.
| |
| 10 MR. EBERSOLE: That's right. There is a dual check 11 valve. And these have been validated to close satisfactorily 12 against impact loads?
| |
| 13 MR. HODGE: Yes.
| |
| 14 MR. EBERSOLE: For the smaller break it would be 15 better.
| |
| 16 MR. ROSSI: For the smaller break --
| |
| 17 MR. EBERSOLE: Almost a compensating effect here.
| |
| 18 MR. MCDONALD: One thing I want to make clear. In 19 all the tests when the instrument area is hooked up the valve 20 closes within a 5-second time. During the test it closed 21 sometimes, although it was erratic. The analysis says under 22 no flow conditions it shouldn't close within 5 seconds, and 23 that's why they presented it as a Part 21.
| |
| I 24 In relation to the ability of both the check valve i
| |
| 25 and the valve to close in impact on the seat, in 1976 the l
| |
| | |
| - 1 l
| |
| 39 1 Staff ovaluation requirod licensoos to look and assure when )
| |
| l I
| |
| 2 the valves are slammed shut under pipe load that they don't 3 have a problem. These valves, both the main steam isolation 4 valve and the check valve, are modified, and the operator on 5 the MSIV. It could have been at that time a change in design 6 might have cau,ed some problem, but it was not tested without 7 the plant air system.
| |
| 8 MR. EBERSOLE: Okay. I see.
| |
| 9 Any further questions?
| |
| 10 [No sesponse.3 11 MR. EBERSOLE: If not, Ernie?
| |
| 12 MR. ROSSI: Next we have a situation on Maine Yankee 13 that will be discussed by J.T. Beard from the Office of
| |
| (,,) 14 Nuclear Reactor Regulation, and this is another one that falls 15 in the common mode problem area, which we are always concerned 16 about when we see them. This is a common mode problem with i
| |
| 17 steam generator pressure indication.
| |
| 18 MR. BEARD: As Ernie has said, when we see common t
| |
| 19 mode, or even potential common mode problems, we do get quite f
| |
| 20 concerned. On this particular one, I was involved in a l
| |
| 21 meeting very late last night on this one. I can give you some i b
| |
| 22 assurance that we are definitely looking into this.
| |
| 23 [ Slide.]
| |
| 24 The way I set up the presentation is sort of what I j i
| |
| l 25 call newspaper style. I'm going to hit you with the bottom t t
| |
| i f
| |
| ?
| |
| i t
| |
| u
| |
| | |
| 40 1 lino first, and than como back and fill in with dotails.
| |
| - 2 There were two common mode problems that effectively
| |
| \
| |
| 3 compromised the protection system at this plant for main 4 steamline breaks. A lot of the protection is actuated by 5 sensing low pressure in the steam lines. We have three steam 6 generators at this plant, and each channel has four pressure 7 detectors on it, so we are talking about a total of 12 8 transmitters that feed into four instrument channels.
| |
| 9 What actually took place, the event was that in l
| |
| 10 early August the plant was in two-cycle coastdown. They were 11 down to about 78 percent, pressure was a little low, and they 12 found of the 12 pressure transmitters, nine were not fully 13 open. I point out that's in quotes.
| |
| 14 Then after the plant did come down after that cycle 15 in September, they were running the 18-month tech spec 16 surveillance tests and they discovered that the three channels 17 that were not affected by the root valve problem were 18 essentially wiped out because a year or so ago they had put in 19 a design mod because they were going to tie into the 20 protection system instrument loops.
| |
| 21 The long and the short of it is they didn't do a 22 g c .* d job on that.
| |
| 23 So the end result was all 12 channels were 24 compromistd. I think that also summarizes the item you had
| |
| [~T 25 down here as significance was the main line of defense on a i
| |
| l - _. _
| |
| | |
| 41 i 1 main stocaline broak was compromised by common modo probicas 3 2 and the fact that these conditions had originated during the i
| |
| 3 refueling proceeding, and had been undetected for the entire 4 operating cycle.
| |
| 5 So that was your exposure.
| |
| 6 I have to jump in and immediately follow that up 7 with a comment that there is diverse instrumentation -in the 8 design, and for a number of safety functions, such as tripping 9 the reactor, we fully expect that those would have actuated, 10 albeit slightly delayed, because they are in fact back-ups.
| |
| 11 With that sort of bottom line, I'd like to go on and
| |
| , 12 give you a little more information on each of these two 13 problems.
| |
| O 14 [ Slide.]
| |
| ! 15 I made up a little chart here that shows what was 1
| |
| 16 affected and what was not. As I said earlier, there are three 1 17 steam generators and each has four transmitters. Transmitters i
| |
| 18 converge into one instrument channel. Three of these root i
| |
| 19 valves were found completely closed. Although while they were 20 closed, they were leaking, and the rest of this set were 21 various degrees of fully closed,or just slightly closed.
| |
| (
| |
| l 22 MR. REMICK: When you say leaking, do you mean 23 leaking through the valve seat?
| |
| 24 MR. BEARD: Leaking through the valve and providing 25 pressure through the instrument sensing device.
| |
| )
| |
| f
| |
| | |
| 42-i l
| |
| 1 What actually took place was as they woro consting i
| |
| 2 down, pressure had, of course, come down, as you would expect, O 3 but they found that on steam generator No. 1, one of the 4 pressure channels was -- I guess you would call it sagging.
| |
| 5 It was reading like a hundred pounds lower than everybody else 6 and was acting a little erratic. We called the I&C people in, 7 they checked out the transmitters, it was fine, the instrument 8 loops were fine, so they started checking into the sensing 4
| |
| 9 lines.
| |
| 10 When they went to blow those down, they found out 11 that they didn't behave the way one would expect. As they got 12 to looking into it more, they found out that the root valves 13 were in fact fully closed.
| |
| 14 I would point out the one they found over here was 15 steam generator No. 1, channel No. D, and that root valve was 16 fully closed.
| |
| 17 A subtlety I would like to emphasize is while the 18 root "alve was fully closed, the indicators in the control 19 room were indicating reasonable and normal values. This is 1
| |
| 20 because of the leaking that I pointed out, that they were able 21 on a steady state basis to eventually charge up the line and 22 read something.
| |
| 23 So the real problem was one of what would they do in 24 a transient type condition. The reason they got into this 25 situation was in a previous refueling they had blocked off or s_-
| |
| }
| |
| l i
| |
| i
| |
| | |
| 43 1 wanted to block up instrumontation in order to protect it, in 2 order that they can conduct a hydro test on the steam 3 generators.
| |
| 4 An interesting thing is you notice the A channels 5 apparently were not affected. The reason for that is really 6 all 12 of them had been closed. It was providential that they 7 had another piece of work that involved an Appendix R 8 modification that had a specific step in it that said go back 9 on the ones that we are using for Appendix R shutdown margins 10 -- shutdown panels and make sure these things will reopen.
| |
| 11 So these things have the problem, but through a sort 12 of a separate act they were taken care of.
| |
| 13 Going back here, the problem comes up that,. like 1 14 said, that part was just providential. The root problem seems 15 to me to be that these valves were not on any sort of 16 checklist, not on any administrative controls whatsoever, and 17 the Licensee makes the case, explains that although he 18 realizes today that's invalid, his assumption had been that i
| |
| 19 if the instruments are reading properly, then it's obvious to
| |
| ! 20 everybedy that the root valves must be okay.
| |
| 21 Well, he's learned his lesson now. The Licensee did 22 run some tests, not very quantitative and not highly 23 scientific, but they were trying to get a feel for what might i 24 have been the response they could have expected from these, 25 and depending on exactly how far they are closed down on these I
| |
| | |
| - - - . _ _ . . - -- -. _- - - - - .- _~
| |
| 44 1 root valvos, stop to stop is about fivo and a half turns.
| |
| 2 It's just like a faucet at your home, for your garden hose, O-. 3 depending on how tight you turn it down or how open it is, you 4 could get responses as slow as 30 or 60 reconds type delay.
| |
| 5 But they were -- e x c e,p t for the ones that were fully closed, 6 they would eventually have gotten there.
| |
| 7 [ Slide.]
| |
| 8 Here is another cartoon I drew up to try to show up 9 how these instruments actually come together. This one 10 depicts a typical instrument loop, where you've got the 11 pressure transmitter with the instrument tube actually coming 12 into it.
| |
| 13 Of course, upstream of that is the root valve we 14 were talking about earlier.
| |
| 15 Inside the little dotted box are some parts of the 16 instrument loops that are power supply and test connections i
| |
| ; 17 that aren't related to this event.
| |
| 18 Basically, as you know, the transmitter puts out a 19 current through the loop four to 20 millionth corresponding to 20 the pressure the transmitter sees. The way you get signals 21 out of this loop is by letting that current run through 22 resisters and tapping the whole result into various circuits.
| |
| 23 As I said, up at Maine Yankee, they take these three l l
| |
| 24 transmitters say in the design failures, safety function is to 1
| |
| 25 detect low pressure. So we'll go through a black box that we
| |
| | |
| 45 4
| |
| 1 will call cuotionooring Icw, wo'll find out which of thoso
| |
| - 2 three is the lowest pressure signal, allow that to go into 3 your bi-signal trip unit, and if it's low, it trips.
| |
| 4 CS11de.]
| |
| 5 The situation that they got into was they were doing ,
| |
| 6 a post-TMI related modification, that of installing subcooling 7 monitors in the reactor. TMI requirement was that they have 8 monitoring in the core which would use like core exit l
| |
| 9 thermocouples and reactor coolant system pressure, on 10 recommendation of Combustion Engineering.
| |
| 11 The utility, through their engineering organization, 7 12 Yankee Atomic, decided they would go beyond that and actually l l
| |
| 13 monitor the subcooling conditions in the dome of the reactor 14 vessel, and also pick off temperature-pressure-related signal (
| |
| r i
| |
| 15 to steam generators.
| |
| f
| |
| ! 16 What they were trying to do was to go into the steam l
| |
| 17 generator pressure channels, tap off a signal and use that as ;
| |
| 18 one of the inputs to their shutdown cooling monitor channels, }
| |
| i 19 one of many different inputs.
| |
| l 20 The basic problem they got into was they wanted to i 21 he able to switch these various transmitters into their i
| |
| 22 circuitry. They've got three pairs of wires and they realized i
| |
| 23 if we could do this with a single pulse switch around one ;
| |
| i 24 side, we don't have to switch the *her one, we can save a ;
| |
| 25 little money by a cheaper switch.
| |
| I I
| |
| !_ -.. . _ . _ _ . ~ . _ _ . _ - . _ . . _ - _ _ _ _ _ - - . _ _ . - - . _ ___ _. . . . , . __ _ . _ . _
| |
| | |
| 46 1 The and result was they ostablishod a now ground --
| |
| s 2 I want to put that word in quotes, common return, whatever you
| |
| (
| |
| 3 want to call it, so that they could make the switching easier.
| |
| 4 Now, the mistake they got into was they did not give 5 any consideration apparently to whatever grounding might be in 6 the reactor protection system. So now you end up basically 7 with one circuit and two grounds in it, and that's not good.
| |
| 8 We did resume the design change package. You have 9 to realize that people are going to make mistakes and the r 10 regulatory approach is to design some system that will provide I
| |
| 11 assurance that the mistakes that do occur will be caught. The 12 design review process didn't even address this.
| |
| 13 The post-modification testing was limited very much
| |
| \ 14 to the extent, okay, we wanted inputs to our subcooling 15 monitors, do they now work. The answer is yes.
| |
| 16 Question: Do they look at the RPS system that we 17 are interfacing with? The answer: No.
| |
| 18 Another interesting aspect of this is, as I said 19 earlier, this was done during the refueling outage. Every 18 20 months the tech specs require they do a very elaborate test of 21 the instrumentation for the protection system and the 22 engineered safeguards actuation system.
| |
| 23 They did that test, got their X in the square like 24 in April, and the following month made the design mod and did 25 not see any need to repeat the testing. So that's why the I
| |
| | |
| 47 1 thing want undotootod.
| |
| 2 They do have more frequently a monthly functional Os 3 test that the tech specs require them to do. While I haven't 4 looked at all the details of it, the Licensee made it very 5 clear that the way they performed that test, it's inherently 6 not capable of picking up this problem. So that's why the 7 situation went undetected for the entire oparating cycle.
| |
| 8 I should say it's not in the handout, but this 9 particular utility has really been set back on their heels by 10 this discovery, these two discoveries, common mode problems.
| |
| 11 The utilities plan a lot of corrective actions, some of which 12 are obvious; like, for example, now all the root valves are on 13 the checklist of administrative controls. They are very 4
| |
| 14 concerned that this modification got them into hot water and 3
| |
| 15 it escaped all their nets that should have caught it.
| |
| ; 16 So they are concerned to the extent that they have 17 now launched a major re-review of every design change that has 18 ever been made on that plant, that either directly involves or 19 interfaces with the reactor protective system or engineered 20 safety features, actuation system as an independent design 21 review, f
| |
| i 22 They are backing that up by a proposal to do very 23 comprehensive tests of all the instrumentation, safety-related 24 instrumentation, hopefully to detect these and similar type 25 problems, and they feel so upset by this that they are l.-.._---..- - _ - . , - . - _ _ - . - ._.. . _ _ _ _ _ _ _ - , - - - _ _ _ . - - .
| |
| | |
| 48 1 voluntarily kooping the plant down in ordor to comploto this 2 activity, so that they have a better handle on what will this Os 3 protection system and what will it not do. Because at this 4 point the utility has said flat out they don't know what they 5 have got.
| |
| 6 MR. LEWIS: I'm glad to hear that they are taking
| |
| ! 7 this seriously.
| |
| i 8 For the record, it's interesting that this is the 9 second major problem that has been discovered as a consequence i 10 of the installation of the subcooling meters. Of course, the ;
| |
| I' 11 Crystal River accident was a major consequence of a subcooling l
| |
| t 12 installation. The subcooling meters were only one of the --
| |
| 13 I'd like to call the Crystal River an iatrogenic one, and this 14 is an iatrogenic design problem.
| |
| 15 The subcooling meters were only one of the many mods 16 that were imposed after TMI, and I wonder whether there's a 17 generic problem there in terms of the old adage, that if
| |
| ! 18 something ain't broke, don't fix it. That is, this is two so 19 far discovered as a consequence of just the subcooling meter. l
| |
| ! 20 I wonder if you think there's any other generic issues i
| |
| 21 associated with the very rapid rate of modification of plants 22 in the aftermath of TMI?
| |
| 23 MR. BEARD: I share your concern. NRR is looking '
| |
| 24 into this very carefully, in this just area. We realise not ;
| |
| {i l 25 only post-TM1 -- Salem fixes, a lot of other fixes. But the
| |
| | |
| 49 1 utilition, by and largo, cro hanging a lot of stuff on the s 2 safety-related instrumentation these days, not only for those 3 kinds of reasons, but one side of the NRC 1 <, going out doing 4 control room design reviews. Apparently that's prompting 5 additional indicators and things of this nature, so we are
| |
| - 6 concerned that they are hanging a lot of stuff on it. >
| |
| l 7 I said to the subcommittee the other day that when 8 we wrote a letter, those post-TMI fixes and the Crystal River 9 fixes and whatnot, we did feel it was necessary to tell the j 10 utilities, when you make modifications, don't screw it up.
| |
| l j 11 I'm not so sure that was the correct thing to do. I 12 think we should have said it, but any time you ask a utility i
| |
| i
| |
| , 13 to modify his plant, you run the risk that it doesn't get done j 14 properly, and I think that's what we're seeing.
| |
| l i
| |
| 15 My personal opinion is, well, some of these are very 16 notable messes that they have gotten into. If you look over 17 all of the number of changes that have been made, the number 18 of plants -- the overall numbers that we're talking about, I i
| |
| 19 personally am surprised that there have been this few. But !
| |
| 20 think we as regulators need to recognize that as you said, if i 21 it's not broke, don't fix it.
| |
| 22 Any time you upset the apple cart by any change, 23 there's also a downside to that decision that has to be 24 addressed, or at least cannot be ignoreJ.
| |
| i 25 MR. LEWIS: That's exactly right, I agree with I 6 I
| |
| | |
| 50
| |
| - 1 that.
| |
| s 2 MR. OKRENT: On the same point, I hate to let the
| |
| \
| |
| 3 other aspect of this same issue not be mentioned. Utilities 4 should be able to make these changes directly.
| |
| 5 MR. LEWIS: That was the next thing I was going to 6 say. I agree completely with you, Dave. In fact, in this 7 particular case, when you have add-to electronics, I thought 8 most people know that you should be careful about common 9 grounding or commoning problems. That's a fairly elementary l 10 error to have made.
| |
| I 11 MR. BEARD: I agree. I brought this up to the 12 utility's management a day or two ago, and told them just that 4
| |
| s 13 point. I thought it was a very elementary problem they got 14 themselves into. I guess the only thing I can say is in all i
| |
| 15 honesty, I never cease to be amazed at these plants. This 16 modification was, by the w s,y , done locally, local approval 17 under the provisions of 10 CFR 50.59. It was only because 18 they had an event that it came to our attention.
| |
| . 19 MR. WARD: What do you mean, it was done locally?
| |
| 20 Local approval?
| |
| 21 MR. BEARD: What I mean is local approval is when i 22 the utility designs and reviews the mod and makes the final 23 approval to install this modification and the NRC is not i 24 involved in that review and approval process.
| |
| 25 MR. REMICK: I assume they reported that to you on e
| |
| i 4
| |
| . , - - - - - - , _ _ --- - - - - - -_ , ._.-__-._..s_..
| |
| | |
| 51 1 tho 50.59, their annual 50.59 roport prosumchly had that 2 information in it?
| |
| i \
| |
| ,/ I have not gone back and rechecked this 3 MR. BEARD:
| |
| 4 particular item, but I presume they met the regulation. They i
| |
| 5 gave us a list of all the modifications they put in the plant 6 the last year or two.
| |
| 7 MR. SIESS: But nobody looked at it?
| |
| i 8 MR. REED: Could you walk me through the fundamental 9 safety significance of, let's say, these two things related to 10 pressure, loss of rapid pressure response on steam line 11 breaks? Walk it through to where it might interface or cause 12 or lead us to potential for coremelt.
| |
| 13 MR. BEARD: I'll give it a shot. I have to say we 14 have not completed our review, as you can imagine. This thing 15 just came up.
| |
| 16 Let me say as I get started here, the Licensee has 17 done an analysis of just what you are bringing up, Glenn.
| |
| 18 They did an analysis that started out with saying, okay, let's ,
| |
| i 1
| |
| 19 just postulate all of our pressure instrumentation is dead, l
| |
| 20 for whatever reason. They we will go on and we will say what ,
| |
| 21 piece of equipment or actuations would be presumed reasonably 22 to be disabled by that, and secondly, what pieces of j 23 instrumentation or equipment could we reasonabl,v presume would 24 still be available?-
| |
| 25 Then we went through all the analytical c a l c u ', a t i o n s r
| |
| I
| |
| | |
| . _ . _ _ _ . _ _ _ _ _ _ _. _ . _ _ _ _ . _ - _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ m.
| |
| 52 1 with the computor ocdos and whatnot, and they oamo up that 2 because of the backups, it looks as though the plant would not 3 return to criticality and return to power, that that would 4 still be precluded; but there are some parts of that -- we
| |
| - 5 have not reviewed that analysis yet, Let me tell you what I 6 think we know about it. ,
| |
| i i 7 On main steam line situation -- and Ernie, please, ,
| |
| 4
| |
| . 8 if I make a mistake, please correct me -- there are three 9 things you generally want to do. One is to isolate the steam i
| |
| 10 side of the steam generator. Most plants use MSIVs for that.
| |
| 4 11 The second one is you want to isolate the main feedwater side ,
| |
| 12 to curtail the amount of overcooling you get, and the third f i
| |
| 13 function is related to getting your aux feedwater up and ,
| |
| 14 running.
| |
| {
| |
| 15 MR. EBERSOLE: Don't you protect the containment ,
| |
| t
| |
| ., i 16 from high pressure by turning off the feedwater as well? >
| |
| 17 MR. BEARD: Yes. That's one of the other reasons f i !
| |
| ! 18 for it. You are correct, Jess 2.
| |
| i I t
| |
| ! 19 At this particular plant, the way they isolate the ;
| |
| l 20 steam side of the generators is through what they call excess !
| |
| 21 flow check valves. These check valves are operated by this [
| |
| ?
| |
| i 22 pressure instrumentation, so that function would be lost. The ;
| |
| i 23 way they isolate main feedwater is through another gadget -- I j 1
| |
| ; 24 have forgotten what it was -- but those gadgets are operated [
| |
| , (
| |
| ) [
| |
| 25 when the excess flow check valves operate, so they would be !
| |
| f i
| |
| i I T
| |
| l
| |
| | |
| 53 ,
| |
| 1 lost, so foodwator isolction valvos would not be totally
| |
| _ 2 closed.
| |
| 3 They realize -- and if you look in their accident 4 analysis section of the FSAR -- that if you don't shut off aux 5 feedwater, isolate it, that all the water goes into the break i
| |
| j 6 and that makes it quite bad. So one of the safety functions 7 is to isolate the aux feedwater system to feed the break, and 8 that function would be lost also.
| |
| 9 In their analysis they say if, however, we take 10 credit for the reg valves in the feedwater system and assume i
| |
| 11 that they will close because we' will get high steam generator 12 level on the swell due to the break, which will give you i
| |
| 4 13 turbine trip, which will come back and give you reactor trip i
| |
| 14 and isolate at least the feedwater system of running it back i
| |
| i 15 or completely closing it, if we take credit for the reg valve,
| |
| , 16 then we will get some help in that area. That's normally not 17 allowed in the licensing process.
| |
| 18 The end results of their analysis are that if we get l
| |
| 19 credit for that kind of thing -- this is a best estimate l 20 kind of thing. not licensing analysis -- it looks like they 21 will get a backup reactor trip on the steam generator high 22 level pretty quick. If not, they will get it in something
| |
| ; 23 like 5 seconds, according to their analysis, because of the 24 containment high pressure signal tripping.
| |
| l 25 They didn't give us a whole lot of information on i
| |
| l
| |
| (
| |
| | |
| 54 1 what le going to hoppon in the secondary sido, and we had semo 2 serious questions in that area, but they did really look at 3 this question of would the reactor return to power, and they 4 believe that it will not if you take reasonable best estimates 5 type analysis and use credits for nonsafety-related things, as 6 Charlie was bringing up. But in the licensing space, that 7 doesn't hold water. We are trying to focus our attention, at 8 least on the side of the effort that I'm working with, in what 9 I call the real safety issues of the concern and try not to 10 trip over our sneaker strings in the regulatory aspects.
| |
| 11 I'm not sure how well this answered your question.
| |
| 12 MR. REED: I think that's what I want to know, was 13 it really significant with potential for core decay heat 14 removal in jeopardy. It doesn't look like another arrow for 15 my quiver. I keep trying to store arrows.
| |
| 16 MR. WARD: You need another quiver, I think.
| |
| 17 MR. SIESS: Back to the issue of whether changes are 18 made correctly. A lot of errors that are made during 19 construction are detected during the preoperational testing; 20 am I correott 21 MR. BEARD: On a new plant you are absolutely 22 correct, and that's what we hope for.
| |
| 23 MR. SIESS: Is there a comparable program of testing 24 that could be expected to discover errors made in 25 modifications?
| |
| | |
| . - _ . _ .. _ . - ~ - , - . , . - - . -
| |
| 55 1 MR. BEARD: The answor to that question is that wo s 2 have made a lot of improvements in this particular area since s
| |
| 3 the Salem ATWS. One of the big things was a program called 1
| |
| 4 post-maintenance or post-modification testing. They should 5 undertake a comprehensive test to make sure not only does the l 6 function you are trying to add work properly but that you !
| |
| 7 haven't had it configured with other parts. That program has e just be lodged a year or so ago. It has not been fully ;
| |
| 9 implemented at a lot of utilities.
| |
| 10 We explored that very point with this particular 11 utility because they have already given us commitments on what I
| |
| : i. ,
| |
| 12 they are going to do with this kind of testing. When I was i
| |
| 13 talking to their management, I said, have you looked at the 14 question of whether or not you did the kind of i
| |
| 15 post-maintenance or post-modification test that you told us .
| |
| 16 you would do? That's the first question. The answer was yes, i
| |
| ?
| |
| t 17 we did everything we were obligated to do. ;
| |
| i 18 Second question: Were your obligations, your outline l 19 of what you would do, did you consider that those were 20 adequate? Answer: Clearly they were not adequate. !
| |
| 21 MR. SIESS: So they did what you told them, but that i
| |
| 22 wasn't adequate. !
| |
| 23 MR. BEARD: They did not do what we told them. We I
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| ; 24 told them simply to propose a program of post-maintenance, 25 post-modification testing that would adequately address safety
| |
| | |
| 56 1 concorno. They dovolopod a program to hit that gonoral s 2 requirement. We did not tell them how to do that testing in
| |
| \ss 3 any way, shape or form.
| |
| 4 MR. SIESS: You don't have to approve what they 5 proposed?
| |
| 6 MR. BEARD: I think the NRC does review 7 that. Whether they issue a separate approval or whatnot or j 8 whether there is reason to do that, off the top of my head I 9 can't give you an authoritative answer.
| |
| I 10 MR. ROSSI. Even if we were to approve it, it would 11 be an audit review. We don't go through every detail of every 12 single procedure in every program. You know, I think there 13 are a couple of lessons that I like out of this event. One of 14 them is post-modification testing. You know, you can look for 15 grounds that are in the wrong place. I just believe no matter 16 how good you are in doing that, you are probably going to miss l
| |
| 17 some. I really think post-modification testing is very 18 important in picking up this kind of a problem.
| |
| 19 The other thing is the kind of things that cause 20 common mode failures in systems. This is a good example of 21 what we have, I think, recognized for years as possible 22 producers of common mode failure.
| |
| 23 MR. SIESS: Ernie, it seems to me that raises a 24 question of why you do a review. If your review is only an 25 audit-type review and it doesn't discover the deficiencies in i l
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| i l
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| \
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| [
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| t
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| | |
| 57 l-
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| [
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| 1 the lisonsoo's proposal, why is NRC wasting its timo doing r
| |
| ,_ 2 such a review? I mean do you salve your conscience? f l (s-) 3 MR. ROSSI. I think the reviews we do certainly l
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| I 4 place a lot of emphasis on licensees developing good programs, j 5 and we follow those up with what we are doing here when we l 1
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| t I
| |
| 6 find glitches in their programs. We go back and look at what i
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| 4 I 1
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| 7 they are doing to correct it. !
| |
| i '
| |
| 8 MR. SIESS: If you had never even done the review, L
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| 9 you would have ended up at the same point, you are telling me.
| |
| 10 MR. ROSSI, We may have had more of that to do, I l
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| 11 think. 6 l
| |
| I f 12 MR. EBERSOLE: Isn't there a ritual -- certainly p f
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| 3 i
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| 13 there is a golden rule that no piece of protective system is j
| |
| ! I
| |
| ) 14 ever bought without a price, and isn't there a ritual or [
| |
| t !
| |
| I l 15 routine that certainly says, when you do anything like f
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| ' i
| |
| : I j 16 this: What the hell have I done wrong? l l L s
| |
| , 17 MR. BEARD: There are supposed to be, Jess. I l
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| l 18 Unfortunately, in my personal opinion the criterion for that l l
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| l 19 kind of stuff is in 50.59, and it says you are supposed to do 20 a review, you, the utility, are supposed to do a review. If 21 it meets certain tests, you don't have to submit it to the j i
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| 22 NRC. I think the basic root of the root problem is those f c
| |
| I l 23 determinations are done in a rather superficial manner. [
| |
| ! I f 24 We looked at the 50.56 review of TMI, They didn't I I
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| 25 address but about half the criteria. I'm a frustrated f l
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| I f
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| I
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| | |
| . . - - - .. - - ._ _ ~ . - _ _.- - - --__._. - -
| |
| 58 1 onginoor, you knew.
| |
| 2 But going back a little bit to the question of the O 3 NRC reviews, I think part of the problem is this agency is 4 trying to reach some balance between taking 30 years to 5 licensing of the plant and doing a good, responsible job 6 protecting health and safety and keeping the job to a 7 manageable size. And the NRC is trying to give some credit to 8 the fact they are using good engineers to design things, 9 hopefully, and they generally are. Their Appendix B 10 requirements to 10 CFR 50, quality assurance, say you have got 11 to have designer reviews, and the corporate does all that kind
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| }
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| l 12 of thing. They have plant safety review committees.
| |
| 13 By the time it gets to us, hopefully with those s
| |
| 14 layers of review, the government's review should find no 1 15 problems, and we therefore can take some assurance that we 16 don't have to review 100 percent of the plant, or we would i
| |
| 17 have to have just as many engineers and just as many years as 18 the architect engineer or the vendor. So you run into 19 societal kind of questions, too.
| |
| 20 MR. SIESS: That sounds great, but it just doesn't !
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| 21 catch the problem.
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| 22 MR. BEARD: Absolutely.
| |
| 23 MR. EBERSOLE: Standardization in detail will catch 4
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| 24 the problem, I think.
| |
| i 25 Go ahead, Carl.
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| l (
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| | |
| 59 1 MR. MICHELSON: What I wanted to ask about is this 2 problem of -- well, it's a three-part question. The first 3 part is to what extent now or how are you transmitting this 4 information to other utilities so that they take care of this 5 question of leaving valves partially open or completely 6 closed? You should tell us a little about that.
| |
| 7 The next part of the question is that instrument 8 valves aren't the only problem. There are hundreds or 9 thousands of small valves which are nonmonitored and for which 10 you can't even tell their positions, necessarily, around the 11 plant, many of which can inactivate engineered safety 12 features. So why aren't you extending this on to them?
| |
| 13 So the third part of the question is are you doing a
| |
| ( 14 study of this whole question of leaving nonmonitored valves in 15 improper, conditions? And I think this has to go beyond the 16 old AEOD study in which they looked at the wrong train, wrong 17 valve kind of situation, and now look at leaving these 18 unmonitored valves in various positions and there is no 19 knowledge on tre part of the manage 6 ent that they are in a 20 nonacceptable pbsition.
| |
| 21 MR. BEARD: Let me see if I can take that question a 22 piece at a time. It is my belief -- and Ernie, correct me if 23 I'm wrong -- that ISE is considering an information notice to 24 get the word out on this.
| |
| 25 MR. ROSSI; That's correct.
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| \
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| l l
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| | |
| 60
| |
| )
| |
| , 1 MR. BEARD: So ws will lot pooplo know abcut thoso I
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| 2 occurrences and lessons to be learned from them.
| |
| O
| |
| < G 3 MR. BEARD: The second part of it, if I remember it l
| |
| 4 properly, or in order --
| |
| 5 MR. MICHELSON: Other valves.
| |
| 6 MR. BEARD: It has to do with other valves in which I
| |
| 7 the same disease might exist. I don *t know that the agency 8 has decided exactly how and who is going to address that part 9 of the generic applicability question, but I can tell you from
| |
| , 10 meetings even late last night the generic applicability is 11 definitely being pursued. It may turn out AEOD in a better 12 charter might be asked to look at this question again, i 13 MR. MICHELSON: Is there a possibility it might be a 14 generic issue and go through that process? i
| |
| ; 15 MR. ROSSI Valve verification, I think, has been 16 recognised as a generic problem for a number of years and has 17 been addressed and readdressed with notices --
| |
| i i
| |
| i 18 MR. MICHELSON: They keep addressing big ones. They :
| |
| l 19 , don't address all the little half-inch, three-quarter inch 20 that can get you into big trouble. They recognise they are i
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| i 21 there but they don't address them in the programs. I'm not 1
| |
| i 22 satisfied that you have a program presently in the industry i
| |
| l 23 that takes care of these malpositioning of nonmonitored i
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| i j 24 valves.
| |
| I L
| |
| . 25 MR. ROSSI: It is clear that the program is not 4
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| e i
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| | |
| 61
| |
| ! 1 working well onough.
| |
| 2 MR. MICHELSON: This is just an isolated incidence.
| |
| 4 O 3 In the last year, you can go down -- fortunately, the LERs 4
| |
| 4 don't report all of these any more because they don't have 5 to. Only when you do a whole bunch of them at once and really !
| |
| 6 screw it up do you even have to report it.
| |
| i 7 MR. EBERSOLE: May I ask this question of the NRC at 8 1arge --
| |
| i 9 MR. MICHELSON: He has got a third question.
| |
| i 10 MR. BEARD: I have a third answer. The answer, in 1
| |
| 11 my personal opinion, to your third question about the generic 4
| |
| 12 problem is we as an agency have been licensing plants on the i 13 basis of single failures, and we have to come to grips with 14 this question for the common mode problems that are popping up
| |
| ; 15 out there in the real world.
| |
| 16 As the Chairman has said, we have to look at that i
| |
| 3 17 whole thing as a licensing basis, and we at NER try to come to l
| |
| i 18 grips with not only where is it going to happen next, how is l 19 it going to happen, but what can we do to prevent it. We 1
| |
| : 20 don't have all the answers yet, but we are definitely working 1
| |
| ] 21 on the problems.
| |
| i i
| |
| . 22 MR. MICHELSON: My question was do you actually have I
| |
| 23 a study under way or are you still thinking about it?
| |
| r
| |
| , 24 MR. BEARD: A study under way on the valves or i t i
| |
| l 25 common mode?
| |
| I . _ , - . _ _ . . . - - - . _ - _ - . _ _ _ . - _ . - . _ _ - .
| |
| | |
| 62 1 MR. MICHELSON: Positioning of malpositionod velvos.
| |
| 2 MR. ROSSI: I don't know of any particular study. I 3 do know it is a continuing concern within the agency, within 4 the regions on malverification in general.
| |
| 5 MR. MICHELSON: The reason I asked is I have been 6 reading LERs from time to time over the last year and I see a i
| |
| 7 lot of this. It's in old LERs, unfortunately, that are now 8 beginning to phase out, so I don't see as much because.they 9 aren't reporting it as much. But is there any kind of 10 organized look at what we have seen in the past when it was 11 reported?
| |
| 12 I think it is almost a worthwhile undertaking.
| |
| 13 MR. BEARD: We expect AEOI to do that kind of thing.
| |
| 14 MR. REED: I just wanted to carry on on what Carl 15 said a little bit and what Mr. Rossi is saying. There are, of I
| |
| 16 course, many what are key safety-related valves that are on 17 monitor lights in the control rooms. Then there are tens of 18 thousands of other valves. Let's say nines of thousands are 19 not at all safety related, but it appears to me here the i !
| |
| 20 check-off list was deficient.
| |
| 21 Now there is verification validation into operator i i 22 attention -- this is a requirement -- attention to valve 23 position, so I really think what Carl is talking about, yes, ;
| |
| i 24 that's ongoing; but when you are operating and using some tens 25 of thousands of valves, invariably somebody is going to have
| |
| )
| |
| i I
| |
| i !
| |
| | |
| 63 1 cno off tho chock-off list or make a mistake and wo are going g 2 to hear about that incident, and we really want to know what 3 its significance is.
| |
| 4 MR. EBERSOLE: Any other questions? I was just 5 going to ask why wouldn't it be appropriate to mandate that 6 every important valve, safety valve be sealed closed with a 7 lid seal with an individual's name on it.
| |
| 8 MR. REED: I think that is a practice, Jesse, but 9 rather than having individual names, there was a number tag, a 10 plastic number tag on the valve which goes back to the 11 check-off list which says it was operated in position on a 12 certain day and it is traceable to the operator.
| |
| 13 MR. EBERSOLE: I am after traceability, b
| |
| (,j/ 14 MR. MICHELSON: The problem is, at least in a number 15 of plants I have toured I have been looking for this, and I 16 find it is good on the 2-inch and up kind of valves; I find it 17 is nonexistent on half-inch or 3/4-inch.
| |
| 18 MR. EBERSOLE: I said why wouldn't all of them?
| |
| 19 MR. MICHELSON: That's my problem. There's no set 20 practice in the industry that goes down to every one of the 21 half and three-quarter inch. I have rarely seen it on 22 instrument valves.
| |
| 23 MR. BEARD: We were here before you some months ago 24 on a number of problems of dispositioning of isolatnon valves 25 and scram systems, hydraulic control units. The same comments f
| |
| | |
| 64 1 ocmo up. Tho only thing I can really scy in response to your
| |
| : 2. question is this is an advisory safety group and you may
| |
| . b)
| |
| R.,
| |
| 3 choose to make that recommendation.
| |
| 4 MR. EBERSOLE: I think that's right. We have to 5 consider that.
| |
| 6 Any further questions?
| |
| 7 [No response.]
| |
| 8 MR. ROSSI. The next item is discussion of new pipe 9 crack indications which have occurred at Peach Bottom, and 10 that discussion will be led by Jerry Gears from the Office of 11 Nuclear Reactor Regulation.
| |
| 12 MR. E B E R S O l. E : Dr. Shewmon, this was especially in 13 your direction.
| |
| l 14 MR. GEARS: My name is Jerry Gears. I'm the Project 15 Manager for the Peach Bottom facility at NRR.
| |
| 16 [ Slide.] ,
| |
| 17 I would like to present this morning a quick 18 overview, at least as it refers to the ongoing IGSCC 19 inspection at Peach Bottom Unit-3, highlight some of the areas 20 that have been again focused because of the offense at Unit-3 21 and also present some actions that we are taking within the 22 NRR staff at this time and within I&E to address'the issue.
| |
| 23 As I discussed last Tuesday, Unit-3 is currently 24 down, in shutdown phase, and is undergoing an 84-11 inspection 25 to do a brief history of the IGSCC problem. As you may
| |
| | |
| 65 1 rocall, thoro are sovoral ISE Bulletins on IGSCC, 82-03 and :,
| |
| 2 then 83-02. Based on the results and findings of those !
| |
| 3 bulletins, the Staff was -- there was a heightened interest in 4 the crack phenomenon on BWRs. Back in 1984, we came out with !
| |
| r i a generic letter describing and telling Licensees essentially f i
| |
| 6 that we were interested now in a reinspection phase, but we j f
| |
| 7 wanted them to go during each shutdown and do another i 8 inspec, tion program. We set out guidelines of what we i
| |
| 9 considered to be an adequate inspection program. That's ;
| |
| 10 currently what Unit-3 is undergoing. .
| |
| r 11 Last month, we started to get some of the results of [
| |
| 12 this program. As my second bullet indicates, we are seeing +
| |
| t 13 numerous cracks. I guess, at this point yesterday, we [
| |
| t 14 checked, since the program is still going on, that we are 15 talking on the order of 27 or 28 valves that have been L
| |
| ?
| |
| 16 determined to have cracks. !
| |
| 17 I mentioned here the GE SMART system. ;
| |
| 18 MR. SHEWMON: Did you say valves? You don't mean
| |
| * I 19 valves, do you?
| |
| 20 MR. GEARS: Welds. Excuse me. Cracks on welds. 28 ;
| |
| 21 welds have crack indications, f
| |
| 22 MR. OKRENT: Maybe if they looked at the valves, ,
| |
| 23 they would find cracks. ;
| |
| 24 MR. SHEWMON: If they could look at them, they ;
| |
| t i
| |
| 25 would.
| |
| s ,
| |
| e t
| |
| | |
| 66 1 MR. GEARS: The GE SMART system is montionod hero in 2 passing, because apparently it's the first time it's being D
| |
| d 3 utilized. It's an automated system that is being utilized to 4 the fullest extent at a BWR inspection program.
| |
| 5 MR. SHEWMON: Do you know what is " smart" or 6 different about that one? It's a tricky name.
| |
| 7 MR. GEARS: I guess I can talk a little bit about 8 the system in a general fashion. I think there's currently 9 several automated systems out in the field. The GE system, I 10 guess the main characteristics, like most automated systems, 11 is essentially it allows the inspectors to sit in an area of 12 reduced radiation and gives them a time, a more relaxed time 13 period to actually look for cracks, and in that case the O 14 meaning of " automated" here means that the transducers can be 15 controlled by the inspectors and in a fairly safe area.
| |
| 16
| |
| * MR. SHEWMON: Does that mean they also record the 17 signal?
| |
| 18 MR. GEARS: They are all recorded on all sorts of 19 taping, a computerized video tape system, and go back over and 20 over again.
| |
| 21 This particular system and its operators have gone 22 through the EPRI Center for certification and have passed.
| |
| 23 There are, as I say, from my understanding, other automated 24 systems out there, but this is the first one that we know of 25 that has gone through a fairly rigorous use. I think 1
| |
| \
| |
| - ~_ -. - -- _. - - - - . ,.
| |
| | |
| 67 1 semothing up towards 75 poroont of the wolds at Peach Dottom 2 have been looked at first by the system.
| |
| k' 3 A little bit more about the way they use the system ,
| |
| 4 is, as I say, they try to take a first look with the automated 4 5 system. If indications are seen, they have two onsite, 6 independent NDE teams, Southwest and General Electric, who go 7 back and do manual confirmation.
| |
| 8 As far as we know today, the confirmation has been 9 100 percent manually what the system has been showing. The 10 significance is, I guess, highlighted in Bullet 3, not that 11 we're just seeing cracks, but that the cracks apparently are 4
| |
| j 12 on welds that were originally called in 1983 to be clean or 13 at least were raported to be clean.
| |
| 14 We have some additional data that the Licensee has 15 provided, based on 1983, which provides a comparison of the 16 '83 data with the '85 data, i 17 Most of these welds have what is called -- back in
| |
| ; 18 1983, it was called geometry or root geometry, and therefore
| |
| ; 19 in 1983, based on those indications, they were considered top 20 be crack-free.
| |
| 21 One of the cracks -- well, actually as of yesterday, 4
| |
| 22 we understand there i s more than one, but we're talking 23 perhaps two or three of the cracks are fairly significant in i
| |
| 24 terms of length, what we would call 360-degree 25 circumferential, and this one here is the deepest one so far
| |
| .-a - . - , - - . . . - - - . - -
| |
| -- , - - - . ,-.-------------n -n. - - . ,
| |
| - , - -w, - - , - - . - - - _
| |
| | |
| 68 l
| |
| i 1 of that siso. It's upwards of 55 porcont through-wall. j l
| |
| 1 2 Most of these cracks have been discovered on welds i O 3 that had received IHSI induction heat stress improvement, not 4 all, but most of them.
| |
| 5 MR. MOELLER: Could you refresh me on what is the 6 rate of growth of such a crack? I mean, if you waited another 7 month or two months or a year, would it be 65 percent? When 8 was it 25 percent?
| |
| i 9 MR. GEARS: I'm not sure if I could handle that. I 10 can give you an indication. There is a fair amount, as you i 11 all would know, of the 55 percent -- fair amount of error in 12 that, anyway, and how good we really know or how well we know 13 these cracks, even in terms of sizing them, once we see that 14 the error band is still fairly high.
| |
| 15 MR. MOELLER: Roughly when was the weld done that 4
| |
| - 16 has now grown to this depth?
| |
| 17 MR. GEARS: When was the weld first laid on this?
| |
| 18 Well, this plant is ten years old, so I would say it's 19 approximately ten years old.
| |
| 20 MR. MOELLER: Thank you.d 21 MR. GEARS: And I would say that what we're saying 22 is, that crack was probably there back in 1983 but was not 23 seen, and therefore was not sized. So I guess there's no 24 indication at this point --
| |
| 25 MR. EBERSOLE: Why do you say '83, when it might be
| |
| }
| |
| | |
| 69 i fivo years oorlior?
| |
| 2 MR, GEARS: That could be; yes, right. That's the
| |
| \
| |
| 3 first time any of these welds went through such a rigorous 4 inspection. It c o til d have obviously been earlier, 5 MR. OKRENT: Do you have a physical reason for 6 discarding the p,ossibility that it grew over a two-year 7 period?
| |
| 8 MR. GEARS: Do we have good evidence that it didn't
| |
| ! 9 grow over two years? Maybe I'll let Warren Hazleton answer 10 that.
| |
| 11 MR. HAZLETON: You obviously realize you're asking j 12 sort of a complex problem, but let me try to cover it.
| |
| { 13 In the case of most of the cracks that have been
| |
| ( ,/ 14 found, the weld had been given the IHSI treatment, and for 15 most of the cracks, small cracks, shallow cracks, we would l 16 expect that the IHSI treatm,ent would prevent any further 17 growth or initiation.
| |
| i J
| |
| 18 The only question that remains for these deep ones 19 and the IHSI treatment, although it puts the inside of the 20 pipe in compression, the outside of the pipe is in tension, 21 and somewhere the stress goes through a zero somewhere around 22 the middle, So if you have a deep crack, the IHS! process 23 could conceivably make the crack go faster than it would have 24 without it.
| |
| l 25 This is the main concern about the depth of the I
| |
| ~ - - - - , - , .--r - - - - - - . - , - -- - ~ - - ,- - - - ~ . - - - - - - -+n, - - - , - - - _ . - . ,
| |
| | |
| 70 1 cracks and the IHSI trootmont. So I think in most of thoso l l
| |
| ,, 2 cases, we are fairly confident that the cracks were there in
| |
| {
| |
| 3 '83 and were just miscalled. They were called geometry and -
| |
| 4 not cracks, which is the main problem with the inspection.
| |
| 5 The other aspect -- (
| |
| [
| |
| a 6 MR. OKRENT: Excuse me. What I'm getting at is, I l 7 am a little interested in trying to see whether, by following i 8 what I will call the obvious interpretation -- namely, "We :
| |
| 1 t
| |
| i t i
| |
| 9 missed it before" -- we could be leading ourselves into >
| |
| ! i 10 missing something, f I h 11 MR. HAZLETON: Yes. You interrupted me. !
| |
| I 5
| |
| i 12 Remember, I said that you can have a problem with !
| |
| r t
| |
| 13 deep cracks and IHSI.
| |
| f 14 The other thing that is of importance that I was J 15 going to mention is, this particular run of pipe had at least [
| |
| )
| |
| j 16 several -- I don't remember exactly -- probably at least two i i I 4
| |
| i 17 full structural overlays on them. This is in the RHI system h 4
| |
| i I
| |
| j 18 that has high thermally-induced stresses, and we recognise the ;
| |
| I i
| |
| j 19 fact that when you have abnormally high stresses, it wipes ,
| |
| i i i 20 out, if you will, a good IHSI. So we are not assuming that f i 21 this crack was present in the same configuration last time; we 22 are looking at the possibility that in some of these cases the 23 cracks have grown since 1983.
| |
| i 24 MR, SHEWMON: Dave, may I ask one question for [
| |
| i 25 clarification? l 1 I I
| |
| I t
| |
| 1 i i
| |
| l
| |
| | |
| 71 1 You said that thoro had boon a couplo of ovorlays on i
| |
| 2 one of these. Is that the one that 360 degrees or a couple of 3 repairs?
| |
| 4 MR. HAZLETON: There have been overlays on other 5 welds using the same pipe run. This one was said to be 6 crack-free in '83, so it had no overlay.
| |
| 7 MR. SHEWMON: When they put an overlay on, it 8 shrinks the pipe?
| |
| i 9 MR. HAZLETON: Then puts higher stresses on the 10 adjacent --
| |
| 11 MR. SHEWMON: And tensile stresses. It will tend to
| |
| . 12 drive the cracks.
| |
| 13 MR. HAZLETON: Yes, sir.
| |
| 4 14 This is, I might say, one of our main concerns about 15 continuing to operate, quote, "with overlays." It isn't 16 necessarily the overlay growth we're worried about; it's some 17 of the other welds that have had additional stresses put on i
| |
| 18 them.
| |
| 19 MR. OKRENT: Let's see, now. I'm trying to 20 understand a broader Staff position. Is it the Staff's 21 position that you will always have leak before break, so even 22 though you have this rather frequent incidence of 360 degree 23 cracks quite a way through the wall, it is not a significant j 24 effect with regard to risk to the plant or public health --
| |
| 25 risk to public health and safety? They may be different
| |
| +
| |
| l
| |
| | |
| 72 1 onewors. Or that the oxistonoo of such cracks, in fact, doos 2 change your perception of the risk, and you might tell me why.
| |
| (
| |
| 3 I really don't know which of those two positions the 4 Staff -- or maybe some third position -- holds, given this 4
| |
| 5 history of quite a f*C, what I would call major cracks.
| |
| 1 l 6 MR. HAZLETON: Well, you ask a very big question.
| |
| i 7 Let me attack one part of it. i I
| |
| 8 We are oversimplifying the situation here when we 9 are describing the crack. The crack is sort of 360-degree, f
| |
| ; 10 intermittent with some areas very shallow and other areas l
| |
| i 11 deeper, with some spots very deep. like 55 percent. But 12 that's just a spot, what we talk about as cusps.
| |
| j 13 And the feeling has been that whatever local stress i 14 situation or other causes, the cusp is going to cause it to go ;
| |
| 15 through the wall at that point first and cause a leak.
| |
| 16 Now one can -- you know, we can discuss this i
| |
| 17 situation all day, but we certainly don't like deep cracks, 18 and we certainly don't like deep cracks that have been given t
| |
| i I
| |
| 7 19 an !HS! treatment, because it has a better propensity for I 20 going through fast. !
| |
| I I i 21 MR. OKRENT: I don't think you answered the basic !
| |
| i i
| |
| 22 question, which is: Do these cracks and their frequency --
| |
| l 23 does this represent, in your opinion, some incremental ,
| |
| , I j 24 increase in risk by posing some increased likelihood of a {
| |
| i r 25 challenge under one or another circumstance? Or do you think (
| |
| l !
| |
| E i
| |
| i r ~ - - - - - , - ,- - , ,--,y-.- , . . - , . . . - , c.,. - - , - - - - - - . . . . ~
| |
| ~ - . . - -
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| 73 1 that they roprocent a vory littlo incromont in risk, if any?
| |
| 2 MR. HAZLETON: I thought I touched on that, but O 3 let's --
| |
| 4 MR. OKRENT: I'd like you to be more specific and not hint. '
| |
| 5 6 MR. HAZLETON: Okay, I'll be specific.
| |
| 7 What we are talking about here i s not specifically 8 new nor unexpected. That is, our attitude has been that the 9 standard residual stress pattern in the weld, plus the i
| |
| 10 standard stresses on the welds, are not likely to cause any 11 problem. We think they are going to leak locally.
| |
| 12 We always have been concerned about the possibility 13 of cracks going through -- deep cracks in IHS! welds. So 1 14 don't see that it represents any different policy. We have 15 recognized this as a possibility, and, of course, that is one 16 reason why we keep harping on doing a good inspection.
| |
| 17 MR. OKRENT: I'm sorry. You know, I still don't 18 have an answer, and I think it's an important question, and !
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| I 19 would like to get an answer from the Staff, if not today, in i
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| 20 the not too distant future.
| |
| I 21 We have been having a record of finding major cracks
| |
| )
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| i 22 of BWR piping, large piping, over a pertad of years. Now it's a
| |
| 23 not necessarily obvious to me that inspecting and finding them 24 is adequate for protection of the public health and safety, if 1 25 there is some significantly increased chance of medium or 1
| |
| .--,--v -. ,.--..-r-- .
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| . , - . , _ . . , , , . , , .-.y-, - . _ , --.-,.-.,,-,-.--.__,..,.,.,m - ,
| |
| | |
| 74 1 largo-oisod LOCA, which will poso o challongo that so for has 2 been answered only on paper and whose ramifications we don't 3 necessarily know, if, as in many other events, there are 4 associated other failures by chance or whatever.
| |
| 5 I, for one -- I must say that I am less convinced 6 than most of your Pipe Review Group seems to be, that pipes 7 having these big cracks have almost the same chance of having 8 a medium or large-sized LOCA, meaning 10 to the -10 per year 9 or whatever it is people calculate.
| |
| 10 I don't believe it. I would like to know what the 11 Staff things.
| |
| 12 MR. HAZLETON: I am not -- clearly, I am not here 13 prepared to talk about the NRC policy on this.
| |
| 14 MR, WARD: Okay. That's probably a question, a good 15 question in this session, you didn't come really equipped to 16 deal with this, 17 Paul, let me ask you, do you think that this recent 18 operating experience indicates the need -- is there something 19 new here that you think your subcommittee should look into?
| |
| 20 MR. SHEWMON: I don't think our subcommittee could 21 come up with any probability numbers that Dr. Okrent would 22 believe, any more than the ones that we spent several million 23 dollars to get out of LLL.
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| 24 MR. HAZLETON: I could discuss a little further what 25 we have been doing about this. This parttoular situation of I
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| [
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| l
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| 75 1 finding orcoks en reinopoetion, that woro apparontly missod 2 during the previous inspection, is not new. We have been 3 finding this ever since early this spring, and as a matter of 4 fact, in -- I think it was June when we had a meeting down at 5 the NDE Center on inspection of overlays, I particularly 6 discussed this situation with the El'R I people. I thought we 7 needed a requalification program for the inspectors to make 8 sure, at least as sure as we could, that people knew what they 9 were doing out there, because we were seeing too many cases 10 where they had been missed previously, 11 And as a matter of fact, we then in a letter, August 12 1st to Georgia Power, we told them that we would expect that 13 they should requalify the people going to do the inspection, 14 perhaps one that is going for the third cycle after the first 15 one, and we do have cooperation from the Owners Group. We 16 have a requalification program going out. We are doing 17 something about it. Whether it's enough or not, I can't say.
| |
| 18 MR. WARD: Let me ask Paul now to finish his 19 thought.
| |
| 20 MR. SHEwMON: There have also been cases of 21 overcalls, which one hears on odd months, this being an even 22 month, or the other way around.
| |
| 23 !s there any way you have of discerning one from the 24 other, or do you see any common threads on why sometimes 25 somebody goes back in and finds that there were one-third or
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| | |
| 76 1 half of what they thought woro orcoks last timo cron't crooks 2 this time?
| |
| 3 MR. HAZLETON: No. We have asked that question 4 innumerable times.
| |
| 5 MR. SHEWMON: You haven't got an answer, then?
| |
| 6 MR. HAZLETON: That's right.
| |
| 7 MR. SHEWMON: One other thing on this so-called 8 SMART system. Do they have in that any kind of signal process 9 particularly?
| |
| 10 MR. HAZLETON: Yes. There's some signal 11 processing. I'm not familiar with it in detail, but it does 12 make a nice picture of the thing. It gives a better call --
| |
| 13 it gives a picture where the operator do a better job with 14 signal recognition, so he can differentiate better, 15 MR. SHEWMON: Okay. Now, as well as people not 16 knowing how to do these things, there is a question of 17 whether people that know how, but att11 would rather do it 18 their own way.
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| 19 MR. HAZLETON: Yes, sir, 20 MR. SHEWMON: Presumably the machine gives you less 21 of that problem; is that right?
| |
| 22 MR. HAZLETON: Yes, that is right.
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| 23 MR. SHEWMON: Or the SMART system.
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| 24 MR. HAZLETON: This is another thing that we have 25 been trying to emphasise, that people can go down to the NDE L
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| | |
| 1 77 !
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| l 1 Contor and loorn hcw to do it. But whother or not they roolly 2 do it when they get out in the field is another question. We ;
| |
| \
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| 3 try to monitor that with our Region people, but they just 4 can't look at everybody and look at all the details.
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| 5 But we are trying to emphasise to the owners that 6 it's their responsibility to see that the people do do the job 7 that they're trained to do.
| |
| 8 MR. SHEWMON: To come back to your part, these 9 things are not -- I guess, let me tell you why I'm somewhat 10 more comfortable than you are, though I don't like what's 11 going on.
| |
| 12 Partly, the cracks are not uniform round, as he has 13 said. So presumably it would go through at some place before 14 others. And then you get back to the usual safety systems 15 which you've got there, since this is a DBA. And I appreciate 16 that you're not comfortable getting close to challenging one 17 of your safety systems, but that, I think, is where we are.
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| 18 Presumably they are better now than they were in 19 '83, not a lot better maybe, but some better, and hopefully 20 they will get most of these things isolated before they come 21 back.
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| 22 One other thing that the Staff isn't here to talk 23 about today, but some utilities are going to come back in and 24 say, "We would like to leave these cracked pipes with overlays 25 and their plus-hydrogen treatment which seems to stop the
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| | |
| ^
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| ?
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| 78 1 erooks frem grewing. And that would bo intorosting to liston 2 to also.
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| 3 MR. GEARS: I want to add to that, that we already 4 have one utility that has added to the life of the plant --
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| . 5 MR. SHEWMON: I've talked to the Licensing people 4
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| 6 there, and they say it hasn't been docketed. They just came 7 in and talked to the Staff, I find it a little slippery
| |
| ; 8 myself.
| |
| , 9 MR. GEARS: I stand corrected, then.
| |
| 10 MR. OKRENT: I'm concerned that there seems to be 11 the possibility of a kind of mind set in the Staff, maybe i 12 broader, that you can't have a LOCA. You know, once you're --
| |
| I i 13 if that is your initial approach, then you say, "Well, if 14 cracks are occurring, we have to find them," but, you know, 15 you're not particularly alarmed, and, in fact, you may or may j 16 not go in to see why you got one where you shouldn't have s
| |
| 17 gotten one. And in particular, you won't go back and evaluate I
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| 18
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| * the b a s,1 c , if you will, premise that we can't have a LOCA and, 19 in fact, factor the possibility of a LOCA in with a range of 20 other operating experience that we have, where, in fact, you i
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| l 21 have multiple things sitting in one event all the time.
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| l
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| ; 22 So despite the supposed design-basis accident aspect 23 and so forth, there may be surprises. I have the sensation 24 that there is too much of a feeling of being at ease with a 25 continuing history of what 1 call major cracks.
| |
| | |
| 79 1 Thoy vary, of scurso. Semo havo boon much worso 2 than this, as we know.
| |
| 3 In my opinion, either the ACRS should have a 4 conscious review of this, or they ought to ask the Staff for a S White Paper in detail which tells us why what the Staff has 6 been doing and is doing is adequate for protecting the public 7 health and safety. I think the situation should not just go 8 on as it has been.
| |
| 9 MR. SHEwMON: What is the status -- let me ask the 10 Staff -- what is the status of NUREG-0313 Rev. 3 or whatever, 11 that is supposed to address this question, 12 MR. WARD: A very short answer, please.
| |
| 13 MR. HAZLETON: A very short answer is that it's in 14 for final typo corrections. I expect -- did expect that this 15 week I would prepare a memo from Denton --
| |
| 16 MR. WARD: That's, your answer, 17 MR. SHEWMON: This is part of the Pipe Study Group 18 that deals with stress corrosion cracking and the report of 19 the sort that Profesror Okrent is looking for. Whether it 20 will have the quality or not he wants, I don't know. We'll 21 soon know.
| |
| 22 MR, WARD: Jesse, I would suggest we have aired this 23 enough.
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| 24 MR. EBERSOLE: We're coming to the end of our 25 allotted time in two minutes
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| \
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| f i
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| 80 1 MR. WARD: Chy don't wo chip the last itom.
| |
| 2 MR. EBERSOLE: The last item was for Bill Kerr, and O 3 it's a matter of discipline versus real significance.
| |
| 4 I did omit one thing. Did we have a company 5 representative from --
| |
| 6 MR. ROSS!! Maine Yankee. I thought somebody from 7 Maine wanted to say something.
| |
| 8 MR. EBERSOLE: If they are here and want to say what 9 they want to do about this, fine. Otherwise, we're through.
| |
| 10 MR. BEARD: Jesse, they decided not to come.
| |
| 11 MR. EBERSOLE: Good, I'm glad to hear it.
| |
| 12 MR. REED: I'd like to make just a quick protest 13 statement, that I do not think the Fermi event should be 14 classified as an abnormal occurrence. I'd Itke that to be in 15 the record.
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| 16 MR. EBERSOLE: Fine.
| |
| 17 MR. WARD: Thank you. Let's take a ten-minute
| |
| ]
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| 18 break, and we will come back with the OESSAR topio.
| |
| 19 (Brief recess.3 20 MR. WARD: The next topic of business is the OESSAR 21 !! review, and I ask Dr. Okrent to take over the meeting.
| |
| 22 MR. OKRENT: Let me first note that on Saturday, !
| |
| 23 expect to have some kind of a first draft letter for the 24 committee to oogitate over. My best guess is that what we can 25 do then is to have a serious discussion of a range of issues, 1
| |
| | |
| 81 i
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| 1 osmo brood, soms opoeifie, and maybo if w3'ro lucky, gain an l 2 idea of the direction in whtoh the next draft should go, and 3 maybe we will ascertain that there are some issues where the 4 committee will want to hear a little more and so forth.
| |
| 5 We held a subcommittee meeting yesterday which 6 oovered a range of topics, and in considerable part, based on I
| |
| 7 what seemed to be well-covered or what seemed to perhaps have i
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| 8 some questions, as well as from the point of view of bringing 9 to mind for the committee certain but not all of the matters 10 that it will have to consider in the overall review of the 11 case
| |
| (
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| 17 There is an agenda which has been handed out, and we t
| |
| 13 will go through it in a minute. ;
| |
| 14 Let me just make one or two observations. One topio l 15 that we did discuss for a little bit at the subcommittee l l
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| 16 meeting, whtoh ! did not put en today's agenda, but whtoh !
| |
| 17 think is something that warrants calling to the attention rf ;
| |
| t 18 the full committee, is that the reactor vessel for a BWR has a t
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| 19 design such that the control rods commence with the bottom i
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| 20 head, and that -- a lot of them, like 100 -- and that, plus 21 the general incore structural arrangement, makes it 22 impractical, I believe -- at least I think that's the state of 1
| |
| 23 the situation -- to inspect certain of the welds at the bottom 24 head, and I believe that it is not the custom to inspect the 25 region between these many penetrations for control rods.
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| I
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| ; ?
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| r I
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| f
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| 82 1 Nrw thic is not -- it is not a woldod rogien, but 2 it's tort of a Swiss cheese kind of affair. And although to
| |
| ! 3 my knowledge, no one has observed any problem in that area, we 4 are talking about very low probabilities of vessel failure in 5 all of the FRAs and so forth. Certain modes of vessel failure 4
| |
| l 6 at the bottom of this vessel could lead to releases which fly l
| |
| 7 in the face of the trends, you know, that people talk about in I
| |
| 8 source term considerations.
| |
| )
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| 9 So it is a question that in some way 1 think the i
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| 10 committee will have a need to think about, but we did not put 11 it on this agenda. It looked like there were enough other 12 topics.
| |
| 1 13 MR. MARX: Just for my edification, there are holes 0 14 through the bottom to accommodate the control rods. In what 15 rough kind of spacing and number do those holes exists? Are 16 they a foot apart, or is it closer than that togethert 7
| |
| 17 MR. OKRENT: You mean from center to center?
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| 18 MR. MARK: From hole to hole.
| |
| 19 MR. REED: It's at least a foot, ;
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| 20 MR. MARK: So it's a very solid, interposing piece 21 between holes. The holes aren't close enough together to 4 22 interact.
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| 23 MR. EBERSOLE: They're mighty close. Well, OE can 24 say that. What's the spacing between the rodst 25 MR. VILLA: Six inches on the housing. l l
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| - ~ _ . _ , _ _ _ _____ _ ._ ___ _ _ _ ,,_ ______ __
| |
| | |
| s 83 1 MR. EBERSOLE: Tho haucing is six inshost 2 MR. WARD: Let's see, could you give your name and O 3 use the microphone?
| |
| 4 MR. VILLA: Rudy Villa, General Electrio.
| |
| 5 I don't have the exact number, but each of the 6 bundles is about four and a half inches in dimension square, 7 and there are at least four bundles in each area, and the 8 blade covers at least four bundles. So I think we'd be 9 talking about at least an eight-inch diameter for each of the 10 housings. There are 205 -- at least over 200 -- that 11 penetrate the bottom of the vessel 12 So 1 think it's probably at least a foot, center to 13 center, of these, and these are welded dirtetty into the
| |
| ) 14 vessel, on the vessel plate on fabrication.
| |
| 15 MR. MARK: And those welds are looked at when 16 performed, but you can't get to them later.
| |
| 17 MR, VILLA: That's correct.
| |
| 16 MR. MARK: Thank you.
| |
| 19 MR. MICHELSON: There's also a two-inch drain line 20 at the very bottom of the vessel which you can look at before, 21 but I don't think you can look at it later, and that is a far 22 bigger hole, of course, than the rods.
| |
| 23 MR. OKRENT: In any event, I'm mentioning this. I 24 thought the agenda was already so full that --
| |
| 25 MR. MARK: This is not unique to OESSAR. This is
| |
| | |
| ; 84 1 tho way things hcvo boon built frca tho boginning.
| |
| 2 MR. OKRENT: The way they are is a question, really.
| |
| 3 Let me, if I can, just read a set of thoughts I sort i
| |
| l 4 of jotted down to, in a sense, ask myself, what are things one
| |
| * 5 should think about in the process of trying to arrive 6 somewhere in this review? So I will just read what are I
| |
| 7 questions here, and it's not intended to be a complete list or 8 in any order of priority, I
| |
| What commitment is the NRC making i i 9 What is an FDA?
| |
| i 10 when it issues onet 11 What commitments would it be making if it approves i
| |
| ; 12 GESSAR !!?
| |
| , r 13 How much detailed information should be provided by ,
| |
| 14 the Applicant for an FDA?
| |
| 15 What should be the level and the depth of the FRA j 16 which is twquired? Should ,it treat uncertainties, as well as 1
| |
| l 17 the state-of-the-art permitst
| |
| }
| |
| j 18 What should the interface requirements with the i
| |
| , 19 balance-of-plant bet How should they be specified, in view of 1
| |
| t 20 the fact that the PRA makes assumptions about balance-of-plant
| |
| }
| |
| j 21 ?orformanoe?
| |
| I 1
| |
| l 22 What seismic fragility requirements should be i
| |
| i j 23 established or are established by the GESSAR PRA and by the l
| |
| ; 24 Staff reviewt I
| |
| l
| |
| ' 25 What other performance requirements for GESSAR !!
| |
| s i
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| | |
| 85 1 cystcms oro ootchlinhod by tho PRA, if anyt 2 What level of PRA evaluation and review should be i
| |
| \
| |
| 3 performed by the Staff, should have been accomplished by the i
| |
| 4 Staff, for it to accept an FDA, and should the Staff report 5 mean values of various important parameters which are j
| |
| 6 evaluated, as well as the state-of-the-art permitst
| |
| , 7 What should be the quantitative safety objectives i
| |
| 8 for future plants?
| |
| j 9 Is there some kind of containment criterion that a I 10 future plant should meet, even though the Staff hasn't come 4
| |
| 11 forth with a proposalt !
| |
| 12 Of course, how to deal in design for terrorists and 13 sabotage in future plants, we haven't talked about, and it's a 14 question I have to think on here, j 15 How should one do cost / benefit analyses for possible 16 design improvementst 17 How does one assure defense-in-depth?
| |
| I 18 How does one assure that the frequency of challenge,
| |
| ) 19 like the number of scrams and so ' orth, is acceptablet l
| |
| 20 How does one judge that the Staff resolution of US!s i 1
| |
| t 21 and generie items is acceptable for OESSAR II? Is there some 22 criterton for judgingt Are there what I will call design 23 matters that should be raised on OESSAR !! as to future
| |
| . l
| |
| !, 24 plants, even though there are current designs which are being I
| |
| 25 accepted for the MARK !!!, for example, changes in the v
| |
| I
| |
| | |
| 86 1 hydrou11e oorca volumos or whatovert 2 And how does one assure that something 1the the 3 considerable number of open issues in the seismio safety area 4 will be handled appropriately, if you grant an FDAt S There are a range of such questions. I will just 6 mention a few.
| |
| 7 There seems to be insufficient information on core 8 internals fragility, according to the Staff's expert panel on 9 seismio safety.
| |
| 10 The Staff has identified the open question on 11 relay chatter.
| |
| 12 There have been recommendations again by the Staff's 13 expert panel that one look for seismic systems interactions 14 -- that is, interactions between non-seismically designed 15 systems and systems important for safety and things like this.
| |
| 16 Anyway, as ! say, this is not a complete list, but 17 1'm just trying to bring out the kinds of questions that, as I 18 say, 1 ask myself when ! try to evaluate, where are we in this 19 review, where am I in this review, and, in fact, you will see 20 that my first question is, in fact, the first topic on the 21 agenda.
| |
| 22 We had quite a bit of discussion in the subcommittee 23 meeting yesterday, just what is an FDA, and what is specified, 24 and I'm not sure that the subcommittee felt that it quite knew 25 even was the Staff was defining as an FDA.
| |
| | |
| 87 1 And then thoro in, perhaps, cur imago 60 to what the 2 details should be.
| |
| 3 MR. SHEWMON: Do you feel you need answers to all i
| |
| I 4 those before you can write a note that says that you think 1
| |
| 1
| |
| : S this will or will not be a significant risk to the public, 6 whether here or wherever it is built?
| |
| 7 MR. OKRENT: I am saying that these are questions i
| |
| ; 8 that certainly come into my mind as I try to think about how a
| |
| i i 9 do I prepare a possible committee report. And in some cases, 10 you raise a question, you think about it and say, "It seems to
| |
| , 11 he okay as the Staff has dont it." In another case, you might I
| |
| 12 look at it and say, "At the present time, the Staff has not 13 tied it down sufficiently with what they propose to do or j 14 whatever."
| |
| .I iS There will be a draft to look at, okayt
| |
| ; 16 MR. MARK: I'm slightly pussted on the matter of the i
| |
| $ 17 PRA. I can imagine doing something called a PRA on the part j
| |
| 18 of the plant that is included in OESSAR, but then almost i
| |
| l 19 everything depends upon things not there, site-specillo i
| |
| j 20 earthquake level, whether it comes from the north or the east l 21 or goes up and down or sideways, watettanks and everything
| |
| {
| |
| ! 22 else.
| |
| 4 4
| |
| 1 23 to will there then have to be a subsequent PRA for l
| |
| 24 the plant that might get licensed, because the FRA on the 25 OESSAR !! itself may tell one something, which certainly
| |
| | |
| 88 v
| |
| i i doesn't tell one what one needs to know? '
| |
| 2 MR. OKRENT: Let me try to give a one or two-minute O 3 answer to that.
| |
| i 4 In fact, the Staff is going to, in its own posit, ton, S require that there be a plant-spectito PRA, at least to cover 6 those parts of the FRA that are not in the OESSAR design or 7 have to show that they have systems or components that meet l q
| |
| 8 whatever GESSAR assumed in its PRA. j i
| |
| i 9 And in the seismic area, you will hear that there i
| |
| 10 will be a need for the utility referencing this FDA to show
| |
| < 11 that its fragilities match certain fragilities that have been 12 identified either by GE or the Staff or show that whatever
| |
| ] l i
| |
| ) 13 they have doesn't produce a significant change in risk. But
| |
| ; 14 we don't have a definition of the word "signiftoant "
| |
| i 15 The question, I think, is complicated by the fact i
| |
| 1 16 that you have part plans, and certainly it doesn't make it 17 easy for -- but it's most; it's part, but it's most -- for OE i
| |
| ?
| |
| 18 to do a definitive PRA. But on tho'other hand, this is i_
| |
| . 19 supposed to be a final plan approval for OESSAR !! itself, and 20 one can ask whether the state of the information, the state of 21 the FRA that was done for GESSAR !!, is done to the level that l
| |
| i
| |
| ! 22 one thinks it should be for a final design approval, and again i 23 whether the review has been done -- an evaluation has been r
| |
| 24 done to the level it should, because presumably performing i
| |
| 25 this PRA was not just a routine thing, intended to have no 4
| |
| | |
| - .- _ . _ . .. =-- - _ . _ . . _ - _ . ... - - - - _ ._ .. . _ _ . .
| |
| 89 i impoet, no significanoo in the licensing.
| |
| 2 Presumably the purpose of doing the FRA was to 3 enable the Staff and the Applicant to get increased insight 4 into the nature of the plant, its strong and weaker points, '
| |
| l S its risks, to enable the Applicant and the Staff to evaluate 6 possible improvements in the plant. And if the FRA is
| |
| ; 7 inadequate for this purpose, then one has not, in a sense,
| |
| > l
| |
| ! 8 accomplished, it seems to me, the intent, as I understand it, I l 9 of the severe accident policy statement of the Commission. I i
| |
| 10 So it's a complex matter, and that's why I put these l
| |
| 11 questions the way I did. I didn't give you any answers. ! ,
| |
| ) 12 want you to think on these kinds of things, and you will have t
| |
| ; 13 to judge for yourself in many of these -- it somewhat all
| |
| [
| |
| 4 14 hinges on, what do we mean by and FDA and when are we willing
| |
| , t 4 I j 15 to say, "Well, we'll buy this," and not agree that it has to 1
| |
| i 16 he a backfit to change and ,so forth, i 17 I would propose we begin with the agenda, i r
| |
| j 18 Mr. Chairman. I notice that at the end of this period we {
| |
| i i
| |
| ! 19 move into some committee business and I am assuming that we ;
| |
| ! i
| |
| )
| |
| 20 might run 30 minutes. [
| |
| ~
| |
| \
| |
| }
| |
| 11 MR. WARD: I hope not too late because we do have a ;
| |
| i 22 full schedule. We are already half an hour into it, i l 23 MR, OXRENT: We're a half an hour into it. I only h
| |
| 24 left 15 minutes at the end for others. j j 25 Okay. The NRC is up for Aenda Item 1. f
| |
| : 1 I
| |
| i :
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| t i
| |
| | |
| 90 1 MR. SCALETTI; Cood morning, my namo in Dino 2 Scaletti from the NRC Staff. With regard to Agend Item 1.
| |
| l 3 Mr. Michelson had asked to put some words on paper so that i
| |
| 4 some questions could be generated. I made an attempt at that 5 to cover basically what an FDA is. I don't know whether you i
| |
| 6 want to generally discuss FDA's or whether you wanted to talk 7 about this recent issuance of Amendment 1 to the OESSAR II 8 FDA. So I will endeavor to answer any questions you have i
| |
| 9 b a s e d ,eJ p on the information that I have given you now.
| |
| j 10 MR. OKRENT: Mr. Michelson?
| |
| 11 MR. MICHELSON: Since I asked for the statement, let I
| |
| ; 12 me say that I think this is exactly what I think an FDA will i
| |
| 13 be, but I need a couple of clarifications.
| |
| j 14 First of all, if I do not find a document referenced 15 in any of these four items that you listed as the scope of the
| |
| }
| |
| 16 FDA, I assume that document is not a part of the FDA approval.
| |
| 17 MR. SCALETT!; If it's not listed, it's'not found in 18 the context of the application, --
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| 4 19 MR. MICHELSON: By application you mean these four 20 documents now?
| |
| ; 21 MR. SCALETTI: Those are just the ma}or four --
| |
| 22 MR. MICHELSON: Walt a minute. If I understand your i
| |
| 23 statement correctly, if it doesn't appear in GESSAR II or its i
| |
| ! 24 amendments or the SER or its amendments, then it's not a part l
| |
| l 25 of the FDA. Is that correct?
| |
| (~)'
| |
| | |
| v 91 1 MR. SCALETTI: Tho application probably ontails moro
| |
| -~ 2 of that. There's other information associated with the V 3 application.
| |
| 4 MR. MICHELSON: It's the other information that has 5 given us trouble from day one.
| |
| 6 MR. SCALETTI: This is the technical information I'm 7 alluding to here. This is the information I assume you're 8 concerned about.
| |
| 9 MR. MICHELSON: I'd like to know to what extent your 10 receipt of technical information constitutes acceptance, and 11 that was the issue from day one. Your statement here I agree 12 with.
| |
| 13 MR. SCALETTI. Our process for final design approval 14 parallels that of a receipt of an operating license 15 application. The information is required by that information 16 identified in 50.34(b), the same level of information.
| |
| 17 Granted, not as much information because with regard to GESSAR 18 it doesn't include the whole plant.
| |
| 19 MR. MICHELSON: Let me correct the statement you 20 gave us, then, because I don't think it's correct.
| |
| 21 The statement you gave us has to include in the 22 second paragraph after the first sentence that the ending must 23 include "and such other information as the NRC might have 24 received." -
| |
| ~
| |
| 25 MR. SCALETTI That's all part of the application. i i
| |
| | |
| 92 1 MR. MICHELSON: Wait a minuto now, road your words 2 carefully. "It must be prosented. -- that means to me it 3 must be in GESSAR II or its amendments. That's the only way 4 you present material. 1 5 MR. SCALETTI. Clearly, I agree.
| |
| 6 MR. MICHELSON: If it's received by you but not 7 referenced in GESSAR II, not referenced in its amendments nor 8 mentioned in your SER, then that document, to my way of seeing 9 it, is outside of the FDA.
| |
| 10 MR. SCALETTI' I tend to agree with you, yes, 11 MR. MICHELSON: Then my clarification is correct 12 that it must be in GESSAR II, stated explicitly, or its 13 amendments or your SER or their amendments.
| |
| 14 So if you receive, for instance, an interface l 15 document which you did not mention' anywhere and GESSAR didn't 16 mention anywhere, that interface document is not a part of the 17 FDA approval. Is that correct?
| |
| 18 MR. SCALETTI: That would be my understanding of it, 19 yes.
| |
| 20 MR. MICHELSON: So we're in pretty good shape, then, 21 because all I have to do is read these four documents and then 22 I know the scope of the FDA.
| |
| 23 The next question is having mentioned the document 24 in one of these four locations, if the document revision t
| |
| ) 25 hasn't been mentioned, only the document number, how do I l
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| l
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| | |
| 93 1 hand 10 the futuro rovimiens of that documont, as for as the 2 FDA approval is concerned?
| |
| ''' 3 MR. SCALETTI: The document revision, if it had been 4 revised, should be identified.
| |
| 5 MR. MICHELSON: If for some reason -- and generally, 6 it's not referenced by revision -- but if it isn't referenced 7 by revision, then how do you handle the problem? You going to B go back and correct these documents and do that?
| |
| 9 MR. SCALETTI. If a referencing document is not 10 handled -- does not include a revision number and it has been 11 revised, only if the review isok place utilizing the current 12 revision to the document, if the application was rev1wed 13 against an earlier revision or the original document, it still k 14 may be an acceptable document.
| |
| 15 MR. MICHELSON: My problem is when I read a 16 reference and find that you've used a certain interface 17 document but didn't tell me which revision, then I have a 18 problem over which revision should I look at and which one is 19 the extent of the FDA approval. It's a kind of sloppy 20 business which QA people would not normally allow, you know.
| |
| 21 MR. SCALETTI: I guess'I agree. The revision to the 22 document should be identified if it has been reviewed >
| |
| 23 Mr. Rosenthal would like to inject a comment.
| |
| 24 MR. ROSENTHAL: Just a point. Chapter 1.7 of the i
| |
| 25 FSAR is a list of drawings. Those drawings are shown, and I
| |
| {''>\
| |
| ~-
| |
| t l
| |
| i
| |
| | |
| 94 1 will hand you the SAR in a moment to includo drawing number 2 and Rev number. Those are delivered in the equivalent of a 3 truck to the NRC, and those are QA drawings.
| |
| 4 MR. MICHELSON: The listing --
| |
| 5 MR. ROSENTHAL: So there are the rev numbers right 6 in the SAR.
| |
| 7 MR. MICHELSON: Our problem hasn't been with the 8 drawings in the SAR; it's been with all the things that keep 9 coming up at the meetings about interface documents, component 10 specifications and so forth, and they say, well, it's in the 11 component spec. Well, my question is: sea s the component spec 12 a part of the FDA approval? And in order to be so, it must be i
| |
| 13 listed in one of the four documents that you have cited, and I h
| |
| 14 don't find it listed in there. I don't find the document in 15 there. Then, what do I assume? I assume that document really l 16 isn't a part of your FDA a p,p r o v a l because it's not listed 17 anywhere.
| |
| 18 It's kind of sloppy. You know, I find this to be 19 not an occasional experience but rather a prevalent one.
| |
| 20 MR. SCALETTI: To be a part of the application-it 21 certainly has to be identified.
| |
| 22 MR. MICHELSON: I think we established what I was .
| |
| 23 worried about. If I don't find it in the GESSAR or in its 24 amendments or your SER and its amendments, then it isn't a ;
| |
| l
| |
| () 25 part of the FDA. If I find it in there but not referenced by
| |
| | |
| 95 i revision, then hopofully semobody could toll me what revision 2 number to look at. But that is just a little bit of .
| |
| ( ') 3 sloppiness, but at least it has to be in these documents, and 4 I think you have agreed that it has to be in one of these four 5 categories.
| |
| 6 MR. OKRENT: It seems to me if they don't tell you 7 the revision number it's really an incomplete statement.
| |
| i 8 MR. MICHELSON: It's unacceptable. From a QA 9 viewpoint this is unacceptable practice, so that the NRC will 10 chastise the utility for it.
| |
| 11 MR. SCALETTI: I must say we have, I believe, a i
| |
| ! . 12 rather competent editorial staff and they do pick up on these 13 items. I do agree that our tech reviewers sometimes tend to 14 be a little easygoing with regard to referencing documents, ,
| |
| j 15 but the endeavor to try to correct all these mistakes.
| |
| 16 Certainly, there are some that get through without 17 being corrected. Maybe the QA is not quite what it should be.
| |
| . 18 MR. MICHELSON: I understand the principle now at ,
| |
| i 19 least. Until today I hadn't really understood what your scope i
| |
| 20 was, and I think that is now nailed down. (
| |
| l 21 I would like to ask, is this GE's understanding of f 22 how it's to be handled as well?
| |
| MR. SHERWOOD:
| |
| 23 That's correct.
| |
| 24 MR. MICHELSON: Thank you. F
| |
| ) 25 MR. OKRENT: Are there any questions members wish to l i
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| l i
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| b
| |
| | |
| 96 1 ask about what the d e f i r. i t i o n or meaning of an FDA is and so 2 forth?
| |
| 3 [No response.]
| |
| 4 I guess not. Then let's go on to the second agenda 5 item where we asked the Staff and GE to add such comments as 6 it thinks are relevant to review the major results and l
| |
| 7 conclusions from their evaluation of the PRA, their !
| |
| i 8 qualifications with regard to the PRA and what their estimates 9 are on the meaning core melt frequency and what their 10 qualifications are on that definition.
| |
| 11 MR. WARD: Are we all set? We need to kind of move ,
| |
| 12 along with this.
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| l \
| |
| 13 MR. SCALETTI: Mr. Rubin from the Staff.
| |
| , ("h i ks s 14 MR. RUBIN: My name is Mark Rubin from Realiability 15 Risk Assessment Branch. Just as a preface to Mr. Rosenthal's 16 presentation I will repeat what I said yesterday at the i
| |
| 17 subcommittee meeting that the internal event core melt 18 frequency numbers that are presented in the Staff's SER are ,
| |
| 19 mean estimates. The seismic core melt estimates are composed l 20 partially of mean values in that a mean component fragility 21 c u r *r e was assembled by Brookhaven National Laboratory and it 22 was combined with an assumed mean hazard function. I i r 23 The reason the end result is not truly a mean value f 24 is that we did not know what the site hazard function would f
| |
| l [ h 25 be, nor indeed any distribution certainly for that function.
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| \ s/
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| % l I
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| r l
| |
| r k
| |
| | |
| ~. _- - _.
| |
| a 97 1 Thoreforo, wo would not charactorize the soismic coro molt
| |
| - 2 frequency really as a mean value. It was treated as that 3 numerically, and if our assumption of the site hazard function l l
| |
| 4 is indeed a mean, then obviously the number woit1d be a mean j 5 result.
| |
| 6 For the total core melt frequency numbers we 7 combined the internal event mean numbers with what was 8 basically a numerical estimate of the seismic to get a point 9 estimate or really a range of possible core melt 10 contributions, and in our sensitivity analysis in SSER No. 4 11 we also presented a range of values. The numbers you will see 12 in Mr. Rosenthal's presentation of core melt.
| |
| 13 That really concludes my comments. The numbers you 14 see in Mr. Rosenthal's presentation on consequences were based 15 -on the numerical estimates, the point estimates for total core
| |
| ; 16 melt.
| |
| 17 MR. SCALETTI: Mr. Rosenthal has some material on 18 Items 2 and 4, 5 and 6. Would you like him to proceed and I
| |
| ' 19 discuss all of those items at one time? It would probably be 20 more expeditious.
| |
| 21 MR. OKRENT: No , I would prefer that we stay with 22 the agenda.
| |
| 23 MR. ROSENTHAL: On Item 2 -- my name is Jack-l 24 Rosenthal, I'm in the Reactor Systems Branch, Division of I
| |
| 25 Systems Integration.
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| s k
| |
| | |
| 98 1 Our risk ostimatos are based on mean values of coro s 2 melt frequency binned into consequence predictions.
| |
| 3 Consequence predictions are really a range of values for which 4 we don't have distributions. At least, I had thought it 5 appropriate that we explain that and how we got there, should 6 you desire.
| |
| 7 MR. OKRENT: We asked the Staff to give a summary 8 presentation in this area and tell us what their major results 9 and conclusions were and where they have qualifications.
| |
| 10 The committee has heard various parts of the picture 11 over many months, and I thought it would be helpful if you 12 could give them what you feel to be the major results and soft 3
| |
| 13 spots in a sort of a capsule picture.
| |
| 14 MR. SCALETTI: Jack, there is some GE proprietary j 15 information in one of these slides. Can we just delete that 16 slide, or we'll have to close the meeting.
| |
| 17 MR. ROSENTHAL: When we get to it, depending on the 18 conversation, why don't we just take it out.
| |
| 19 MR. WARD: Try to delete it if you can.
| |
| 20 CSlide.]
| |
| 21 MR. ROSENTHAL: We have looked at a range of l 22 containment failure modes, and associated with that range of 23 containment failure modes, is a range of possible ways in 24 which fission products can be dispersed from the core.
| |
| 25 I would like to point out that unlike the large dry I
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| - - - _ . -- ~ - - _ _ . -. - . . . - -
| |
| | |
| I 99 1 work that was dono in post years the GESSAR offort was very 1
| |
| 2 much a source term intense effort. j
| |
| [ l 3 [ Slide.]
| |
| 4 When we did the source term wcrk,-- and the 5 divisions were made almost two years --
| |
| 6 MR. WARD: That's a proprietary slide, Jack. If you 7 take it off you can refer to it.
| |
| 8 MR. ROSENTHAL: We had, for several sequences, 9 release fractions predicted in Grand Gulf predicted by IDCOR, 1
| |
| 10 predicted by GESSAR which are proprietary. The Staff spent 11 many hours with Brookhaven. It is a joint Staff /Brookhaven 12 consultant decision on an attempt to pin down a range of what 13 those source terms might be. And we took the releases apart 14 and considered primary system retention, pool scrubbing, 15 deposition settling in the containment, containment failure 16 times in order to derive those source terms. There was just 17 no way of constructing a mean distribution for these values.
| |
| 18 We thought that high and low values capsuled the 19 essence.
| |
| 20 MR. REMICK: Excuse me, Jack, I'm sorry to interrupt 21 but I don't understand what those units are.
| |
| 22 MR. ROSENTHAL: A fraction of the original core 23 inventory released to the environment for a transient event i
| |
| 24 with late containment failure with pool scrubbing.
| |
| MR. REMICK: Thank you.
| |
| O 25 I
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| l
| |
| | |
| 100 i
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| i 1 [S11do.3 i
| |
| 2 MR. ROSENTHAL: The ASTPO code suite looks something O"
| |
| N 3 like that --
| |
| 4 MR. MOELLER: You said released to the environment, 5 not just to containment?
| |
| 6 MR. ROSENTHAL: Released to the environment. We can 7 take that apart if you like.
| |
| 8 But in any case, the ASTPO code suite was exercised.
| |
| 9 [ Slide.]
| |
| 10 And here's a slide that compares our high and low 11 estimates of some time ago with what we would get in the 12 middle column with the ASTPO code suite. I am reluctant to 13 argue that the ASTPO code suite would represent a central ;
| |
| 14 estimate. I'd rather make decisions based on high and low.
| |
| 15 GE's numbers are typically -- in terms of 16 consequences -- two orders of magnitude lower than Staff's 17 numbers, IDCOR numbers, or like GE numbers or perhaps even 18 lower. Just for some perspective.
| |
| 19 So let me repeat again. What we have done is we 20 have glued mean values on the front end core melt frequencies I
| |
| t 21 somewhat with high end sensitivity studies of release 22 fractions in order to calculate person rem, which were in turn l
| |
| ! 23 used in cost-benefit analysis. At least relative to the ASTPO I
| |
| 24 code suite, I don't think our high range numbers are that much ;
| |
| (~' 25 higher than we get with mechanistic codes, k t l
| |
| t I
| |
| | |
| .- . . . - . .. . . . -. - - . _ . - . ..---. . . ._ . . . _ - - - - - .- ~.-
| |
| 101 1 [S11do.3 5
| |
| 2 I have to talk about modes of containment failure 3 for a moment, and then I can encapsulate this thing.
| |
| 4 Calculations of long-term overpressurization of containment 5 occur in the range of 10 to 20 some-odd hours depending if you I i 6 believe INTER or CORCON.
| |
| i
| |
| ?
| |
| . 7 [ Slide.] I
| |
| { !
| |
| 8 MR. ROSENTHAL: Calculations of the burn of 3000 I j 9 pounds of hydrogen in Grand Gulf over an hour show that you f
| |
| f 10 won't overpressurize containment. That is the peak at 40. l 1
| |
| l 11 The rest of the slope is due'to core-concrete interaction, l
| |
| 12 eventually overpressurising containment.
| |
| l l 13 [ Slide.3- l j- 14 We saw high temperatures if you believe MARCH for !
| |
| I !
| |
| 15 the containment atmosphere, and we looked.at the effect of !
| |
| l i i 16 those high temperatures on seals,.and we don't think -- the j 17 most critical seal is the wetwell, drywell. hatch seal, which f i i I 18 we don't think will fail. That still leaves open the question !
| |
| ; 19 of detonations and deflagrations failing containment and your i
| |
| ; 20 own views of the credibility with which we do hydrogen
| |
| ', 21 calculations.
| |
| ! i t 22 [S11de.1 i i
| |
| 23 Given that, we can ~ summarise somewhat flagrantly --
| |
| l 24 we can boil down a dozen containment event trees, _ take several l 25 man years of work,' condense'it down-to one' slide. Please f f
| |
| I l
| |
| | |
| 1 102 l l
| |
| 1 don't winco at some of tho assumptions.
| |
| 2 ISlide.3
| |
| \
| |
| 3 For instance, station blackout. In OESSAR PRA, 4 there is a specific containment event tree for events prior to 5 vessel failure, another one after vessel failure. We just 6 folded them together. The picture we have here is of a plant 7 with LOCAs being some fraction less than one percent of the 8 total ways of getting the core melt. Dominated by station 9 blackout, about 79 percent of the core melt frequency.
| |
| 10 Transients other than blackout are another few percent, and 11 you can use blackout almost as a surrogate for them.
| |
| 12 Loss of containment heat removal, which was a far 13 more dominant event in the RSS, is now about 10 percent. That
| |
| ) 14 includes recovery being taken into account there, and ATWS 15 about 8 percent. On the MARK Is and IIs, ATWS is important to 16 risk. It's a dominant sequence in terms of consequences, t
| |
| 17 although there is a low probability.
| |
| 18 On this layout of the plant we expect to get a fair 19 amount of pool scrubbing *, and hence the consequences of ATWS 20 are far less than what we would have predicted on an older 4
| |
| 21 plant.
| |
| i 22 MR. EBERSOLE: Would you make clear, if that was an 23 ATWS with the program, the mitigative response?
| |
| 24 MR. ROSENTHAL: Yes. If you have the ATWS and you I 25 follow the procedures, you will dump some place between 15 and I
| |
| l
| |
| | |
| 103 1 25 porcont of coro powor into the pool, and 18 socms a popular 2 number, but that is going to switch around. You really have O 3 to do detailed, space-time kinetics calculations to get a good 4 handle on that number, but it is clearly greater than the 5 decay heat removal capability from the pool to the ultimate 6 heat sink, which is in the range of 4 to 8 percent, so you 7 will overpressurize containment.
| |
| 8 The great race here is can you put enough baron into 9 the primary system to shut down the reaction, bring the power i
| |
| 10 lower before you overpressurize containment.
| |
| a 11 MR. EBERSOLE: Did you include in here the 12 probabilistic aspects of doing that without washing it out and 13 so forth?
| |
| 14 MR. ROSENTHAL: The washout wasn't considered. The 15 8 percent number here includes estimates of the reliability of 16 slip. ,
| |
| i 17 MR. WARD: Of the reliability of carrying out this 18 maneuver? Okay. What about the one percent from LOCA? How 19 sensitive is that to the assumption that is made about the 20 probability of a large break? I don't know what number you 21 are assuming for a large break failure, but what if it is
| |
| ! 22 order of magnitude greater than whatever you presume? What d
| |
| l 23 does that do to the one percent?
| |
| I j 24 MR. ROSENTHAL: To capture the essence, let's assume ;
| |
| ! l 25 it's one percent. I'm sorry, it's ten percent. Okay.
| |
| t 8
| |
| V
| |
| | |
| . . - _ - .- . . .- .. - . - - . _ ~ .. -
| |
| 104 1 [Slido.3 2 Let me just point out here that this was without O 3 igniters, which was the original GESSAR proposal, so I have a 4 drywell failure due to hydrogen burns, a wetwell failure due 5 to hydrogen, deflagrations and detonations, late containment 6 failure, and early failure due to -- ATWS is an early failure 7 due to steam production, the TW sequence, or the two T-B3 8 sequences is a late failure due to steam production.
| |
| 9 Now, let's look at the consequences of these events.
| |
| 10 MR. MARK: I wanted to ask you about detonations, 11 You were pointing at an estimate made without igniters, but 4
| |
| 12 there is no sense pointing at such an estimate as more.
| |
| I 13 MR. ROSENTHAL: GE has agreed to put igniters on 14 the plant, Staff has recommended, required that those 15 ignitors be put on diverse power so that they would be 16 available in the event of a station blackout. You do that 17 because of the high probability of blackout. Now, the effect 18 of that is to take these one T-I2, one T-E3 releases. I2 is 4
| |
| 5 19 an intermediate time failure of the drywell, and E3 is an
| |
| ; 20 early failure of the wetwell, and you shift them into L3.
| |
| l 21 MR. MARK: Do you shift them or do you delete the 22 numbers?
| |
| i
| |
| , 23 MR. ROSENTHAL: Core melt frequency would be there, i
| |
| 24 yes, these are deleted, and now the probability of an L3 event 2S goes way up.
| |
| {
| |
| l
| |
| | |
| 105 1 MR. MARK: Thon is detonation any Icngor a thing 2 that deserves attention?
| |
| (~~)
| |
| \"
| |
| l 3 MR. ROSENTHAL: No.
| |
| f 4 Let's go back-to that first --
| |
| 5 MR. OKRENT: We are not so sure about the seismic _
| |
| i 6 qualification of the igniters, so on your detonation question, 7 we want to keep one thing up --
| |
| 1 8 (S11de.3 9 MR. ROSENTHAL: Now, why should one put igniters on i 10 the plant? If you believe GE's risk estimates, it is hard r
| |
| 11 to make a cost-benefit argument. If you believe our ,
| |
| 12 estimates, we still have some troubles making a 13 cost-beneficial argument. The reason to do it is to reduce 14 uncertainties.
| |
| 15 For example, we have intermediate time failures of 16 containmen* due to hydrogen, one called quench, in which the 17 pool fails here, dumping the water into the debris bed and 18 quenching the core. Alternately, if the pool fails and the 19 debris dumps here, you don't quench the core. I personally 20 don't think we should het on the failure given the 21 detonation. The way is to put on a system such as you don't 22 have to worry about it.
| |
| i 23 L3 failures of the wetwell are probable here. If 24 you believe in pool scrubbing and you don't believe in leaks 25 in bypass, then it's okay to blow up the wetwell, but if you
| |
| | |
| l 106 .
| |
| l 1 aro concernod that you havon't proporly closed on bypass or l l
| |
| 2 the drywell, then you would like to preserve this integrity, 3 and what you are doing here is you buy time for agglomeration 4 of settling fission products in the pool.
| |
| 5 You note that my plots of pressurization show 10 to 6 20 hours for agglomeration of settling the L3 sequence. What 7 you are doing is reducing the uncertainty in your estimates by 8 putting on the igniters, and that is the primary effect. It 9 makes the course of the accident more well known.
| |
| 10 [ Slide.3 11 Now let's get back to this slide for a moment. What i 12 I am showing here is that you always fail containment. We had a
| |
| 13 trouble with that as a philosophic approach. Unlike other 14 PRAs where you typically will have a no-fail mode or a 15 basemat which tends to be relatively benign, here we don't 16 expect basemat failure. It's a real thick basemat. But we 17 are concerned in this sort of scenario due to either hydrogen t
| |
| 18 or overpressure you will fail the wetwell, and conceivably 19 another sequence is the drywell, depending on what you believe 20 about igniters. Hence, you always release all of the noble 21 gases.
| |
| 22 What you have bought is good retention of iodine, 23 cesium and the heavier elements, but the price is paid in 24 terms of the nobles.
| |
| 25 MR. OKRENT: This is an important point and one, I
| |
| | |
| 107 l
| |
| 1 think, which the ocamittoo will want to think on Saturday and 2 maybe future Saturdays. Is it appropriate for future reactors 3 to, according to the Staff, have containment design which has 4 a likely containment failure mode which has modest releases, 5 namely, the noble gases, but which has a very high likelihood 6 -- he said always -- let me say a high likelihood of failing 7 given a large-scale core melt.
| |
| 8 One could in principle think of modifications to the 9 design which change this characteristic. I'm not saying it's 10 unacceptable; I'm saying it's something the committee should 11 think about consciously and decide is it okay or not okay.
| |
| 12 MR. MOELLER: Let me ask a question on the previous 13 slide. If you total up the contribution of the various O 14 events, and I realize it's not this precise, but it comes out 15 a little more than 97 percent. Is there anything of f
| |
| i 16 importance, any event that is a major contributor to that 17 other 3 percent, 2 or 3 percent?
| |
| 18 MR. ROSENTHAL: Event V for boiler has the potential 19 for being a bad release category. We can bin it into one 20 1-SB-E1, but I am reluctant to do that. In fact, we have some 21 mechanistic work under way to try to get a good handle on an 22 Event V rather than making untold pessimistic assumptions.
| |
| 23 But if you have to do something now, you bin it into the 24 E1 When we get in the seismic area, for large seismic events 25 we can then introduce other failure modes. I am going to get
| |
| | |
| 108 1 back to that.
| |
| -- 2 [ Slide.)
| |
| 3 Now let me show you internal events as the i 4 calculation is carried out 'o
| |
| . infinity, sample lots of 5 weathers, et cetera for the release fraction of the nature 6 that I showed you on the earlier slides. Bear in mind we may 7 define containment performance in terms of potential for 8 nuclides rather than failure of containment. We calculated 9 sero, essentially, early fatalities, few early injuries and 10 modest latent fatalities, modest latent fatalities, none, l
| |
| l 11 sero.
| |
| ; 12 There is an interesting perspective here. Let's say 13 that one would choose to compare the plant to the safety goal 14 and assume that the core melt frequency was one per 40 years.
| |
| 15 Then would the plant meet the safety goal? The answer is 16 yes, it would, ,
| |
| 17 MR. OKRENT: Well, I'm sorry, excuse me. The safety 18 goal as it was formulated did not have a meaningful societal 19 risk measure. The comparison, where it goes out to 50 miles, 20 in my opinion is almost -- well, I will use a mild adjective 21 -- a misleading measure.
| |
| 22 MR. ROSENTHAL: On earlies. I captured the earlies 23 close in. The latent scale is the person rem. If I shrink 24 this back to 50 miles, I'm going to halve the number. There
| |
| /~N 25 are other I should say to the proposed safety goal, and U
| |
| l
| |
| | |
| _ . _ . . _ _ _ . . . = - _ - . _ _ _ _ _ - _ _ . _ - - _- -
| |
| 109 1 perhaps this in than a moeningful way to defino containmont 2 performance. This answers the question about --
| |
| (.
| |
| t 1
| |
| 3 MR. OKRENT: Let me put it another way. I don't l 4 think, in fact, it would be looked upon as highly acceptable 5 if it were thought that there really were a chance of one over 6 40 years to produce the man rem that goes with those latent 7 fatalities. I don't think that would be -- whether you met i
| |
| 8 the current safety rule or not, I think that indicates why the ,
| |
| 9 current safety goal is deficient.
| |
| 1 i
| |
| 10 MR. ROSENTHAL: Now let's look at Dr. Ward's 11 question with rompect to LOCA and assume that the LOCA 12 frequency is far higher, a larger contributor than the 4
| |
| 13 transients in some broad sense. That switches me between the 4
| |
| 14 1-TL3, which with ignitors I.think is the most probable 15 sequence, to as bad as a 1-SB-E1. That is a small break LOCA 16 without igniters and with early failure of the drywell, and my 17 consequences, my predicted consequences are in person rem a r.
| |
| 18 order of magnitude. But again, low earlies. So from a risk i
| |
| 19 pospective, we should not belabor the precise frequency of 20 LOCAs.
| |
| I
| |
| ! 21 Let's go to seismic --
| |
| 22 MR. OKRENT: Excuse me. There is one other thing
| |
| ) 23 that we need to keep in mind. The calculations of early 24 fatality and early injury are statistical results, so there 25 are some weatner situations which lead to less effects and
| |
| | |
| 110 1 soma, lot's say, which in fact aro not so pleasant.
| |
| 2 MR. ROSENTHAL: But the zero includes bad weathers.
| |
| 3 MR. OXRENT: Oh, the zero.
| |
| 4 MR. ROSENTHAL: If you really believe zero, you 5 really have to be happy about it because you have to have high 6 confidence. We sampled over 91 weathers. You are still 7 getting zeroes. You don't think this is fluke weather.
| |
| 8 MR. OKRENT: In that case you are saying there is l
| |
| 9 sufficiently little release that it doesn't matter what the l
| |
| 10 weather.
| |
| 1 11 [ Slide.)
| |
| 12 MR. ROSENTHAL: Seismic. The difference between the ;
| |
| 13 prior slide, which was internal events, and here etternal O 14 events is that we assume it was .5 or .6 g events that 15 evacuation is impaired. Seismic risk tends to dominate the
| |
| , 16 total risk perspective. And let me remind you these, again, 17 are conditional consequtsces. One can add in -- one has to go j 18 back and say are there new containment failure modes that are 19 introduced by seismic events at very, very large g values. You l 0 just have to assume that sverything crumbles down. We just 21 extracted from Limerick an RSS-type release associated with a 22 massive failure.
| |
| 23 Let's back up a bit and worry about an event which 24 moves the relative motion between the RHR, whatever building 25 you have out here, and the containment building.
| |
| l
| |
| | |
| ._ - ._ _ - - - = . __ .~ - - . .- - -- ,.
| |
| 111-1 [Slido.3
| |
| -w 2 And the piping, the suction lines come right down V 3 the pool and out. If you break that line, then you drain the !
| |
| 4 pool Remember when testing the elements of this design it is 5 that they have pools. We are uncertain of the behavior of 6 that pipe given the SSMRP work and the shift work.
| |
| 7 [ Slide.]
| |
| 8 But the seismic risk is dominated by blackout 9 events, and there you have to provide protection, dominated ,
| |
| 10 at, let's say, .5 to .6 g. The SSE of the plant is .3 g, two 11 times the SSE, and that dominates the risk.
| |
| 12 In comparison, the far higher g events cause the 13 more serious releases yet, but at some perceived reduced s
| |
| 14 probability. That was binned for our cost-benefit work into a 15 1-TI-2, and I believe that is a conservative category. If the S
| |
| 16 ignitors survive, then you would expect what was called the 17 1-TL3, and if you recall, that was an order of magnitude low 18 in person rem.
| |
| 19 One problem here is, given the blackout as the 20 initiator, it looks like some fluid systems that penetrate 21 containment would not isolate. They are closed fluid systems, 22 but of course they can leak, too.
| |
| 23 The I2 sequence, in comparison, is one in which 24 you have assumed that the wetwell and the drywell have been 25 failed by a hydrogen-related event and that has happened at
| |
| | |
| - .- - _ - . - . . , - - _ _ . ~. . - -
| |
| 112 1 semo intormodicto timo.
| |
| 2 This was brought up at the subcommittee meeting. The 3 current Rule 50.46 as revised does not require seismio 4 qualification of the ignitors. Dr. Okrent was right in noting 5 that if you want to take credit for suppression of the risk 6 associated with the seismic events, you are relying on those 7 igniters and you ought to have confidence that the ignitors 8 would survive, and I would say survive to at least 6 g.
| |
| 9 Now, the ignitors have a cabling. Cable trays look l 10 okay. In all the plants that we know of, the ignitors have 11 been seismically mounted, and since G.E. is committed to 12 follow what the owners will eventually do as a result of HCOO 13 on ignitors, I presume that they would be seismically mounted 14 also, but there is no commitment on their part that I know of 15 at this time.
| |
| 16 MR. SHEWMON: Are these things still a glow plug?
| |
| 17 MR. ROSENTHAL: They are a glow plug. They ride 18 around in a diesel. A diesel goes over bumps in the road, 19 they get shaken up and vibrated and everything else, so I did 20 not write -- this came up yesterday.
| |
| 21 MR. SHEWMON: Presumably it is a support system one 22 would have concern about, not the ignitors.
| |
| I 23 MR. MICHELSON: I think you have to have concern 24 about the balance of the system that makes the igniter work, ;
| |
| 25 too, not just the support. ,
| |
| i
| |
| {
| |
| I I
| |
| | |
| l 113 j 1 MR. CHEWMON: I mocnt the support systom.
| |
| I 2 MR. MICHELSON: More than the support, back to the O 3 power supplies, and so forth.
| |
| 4 MR. SHEWMON: You are talking about structural 5 support; I'm talking about anything electrical.
| |
| J 6 MR. MICHELSON: I like to think the function has to i
| |
| 7 be seismically qualified. That includes supports, includes 8 glow plugs and a whole lot of other things.
| |
| 9 MR. EBERSOLE: Doesn't it include just the glow 10 plugs to switch down 2000 psi and diesel cylinders, wires 11 which are flexible and can be put in flexible conduit and 12 immune and removed from cable trays, and a source supply from 4
| |
| 13 a battery which could be put in an enclosure that could 14 withstand a cannon blast? I fail to see the arguments about 15 making it seismic or any reason to think that there's any 16 particularly expensive difficulty in doing it.
| |
| 17 MR. MICHELSON: You forgot controls; you can't leave 18 it on all the time.
| |
| 19 MR. MICHELSON: You've got to see the details.
| |
| 20 MR. EBERSOLE: There are so few details here there's 21 not enough to argue about.
| |
| 22 MR. ROSENTHAL: I wanted to disinguish between 23 seismic qualified, which I would not necessarily recommend, 24 and having high confidence that they would survive. And the 25 first thing that I think one would do pragmatically is just I
| |
| t l
| |
| | |
| - _- .- _ . - _ . ._ .- _ -.-.-. = - - - _ - - - - _- .
| |
| 114 ;
| |
| 1 1 plain teko your fragility people and have them take a hard 2 look at that device.
| |
| 3 MR. WYLIE: Just a matter of education. That .6, is 4 that compared to what on a Richter scale?
| |
| 5 MR. ROSENTHAL: I don't know how to do that.
| |
| 6 MR. WYLIE: I was just trying to do some correlation 7 to earthquakes.
| |
| 8 MR. OKRENT: Let me give you one place where we have 9 a sort of a measure, okay? At San Onofre 2 and 3 wher( there 10 is presumably or postulated to be a fault system which is
| |
| ! 11 active offshore not too far away, a couple of miles roughly as 12 I recall, something like a magnitude 7 on the Richter scale 13 led to a design basis of .66g. That doesn't mean you wouldn't 14 get peaks larger than this, of course, but -- talking about i
| |
| 15 sustained.
| |
| 16 MR. SHEWMON: That's twice as big as anything east i
| |
| 17 of the Mississippi, I think; almost three times.
| |
| 4 18 MR. OKRENT: It's more than twice as big.
| |
| 19 MR. WYLIE: What brought it to mind is, you know, we 20 heard the Chilean earthquake report last meeting, and that was 21 a .7 -- I mean, it was a 7 on the Richter scale.
| |
| 22 MR. OKRENT: It depends on how close you are, of 23 course. In other words, if you're 50 miles away, the plaster j 24 may crack in your house but it's not going to fall down. It 25 shouldn't, anyway.
| |
| l l
| |
| _ _ _ _ _ . _ . ~ _ _ _ - , . __.
| |
| | |
| 115 1 [Slido.3 2 MR. ROSENTHAL: Now one attempts to do cost-benefit ,
| |
| 3 analyses. We do cost-benefat analysis using person rem i
| |
| 4 averted at $1000 a person rem; no present worth. I just 5 wanted to point out that the RHR pipe break massive rupture 6 event V are relatively small contributors to total person rem, 7 in our estimates.
| |
| 8 Seismic dominates a way of giving you what from a 9 back end PRA view is a transient, and that the effect of the 10 igniters is to shift E1, I2, E3 events into the more benign L3 11 category. We have tried to distinguish between ignitors and 3
| |
| 12 perfect ignition here, but we didn't take full credit for the j 13 igniters in doing these incremental person rem. And if you O 14 believe the ignitors will work more efficiently or you don't
| |
| ( ,/
| |
| I 15 believe the detonations in the first place, then you have a i
| |
| 16 greater tendency to bin stuff into the L3 category so you can 4
| |
| 17 show some more cost-benefit.
| |
| 18 [ Slide.1 19 The plant does not have a remarkably low core melt 20 frequency according to our estimates of the range of 5 minus I
| |
| 21 5. What I have been showing you here is very low conditional 22 consequences. The first perception is that our results of [
| |
| 23 overall risk to a great degree hinge on what I consider 1
| |
| 24 judicious use of source terms and the efficacy of the pool. I I
| |
| ; 25 think we were very conservative in the way we treated that 1
| |
| I
| |
| _ , - - . _ . ___ _ - .y , . _ _ . . _ . _ _ . _ _ . _ . _ _ _ . , , . _ _ . . , , . .
| |
| | |
| 116 1 pool scrubbing.
| |
| 2 Logic concerns do exist. The way we have approached 3 the problem there is a tendency to have over-estimated the 4 person rem and in turn, have over-estimated the cost-benefit,
| |
| ! 5 Although as I showed you on the first slide, at least the 6 mechanistic ASTPO code suite numbers are not that much lower 7 than our high range numbers. We would choose not to base 8 conclusions based on cutting the pie that fine.
| |
| 9 [ Slide.)
| |
| < 10 The risk from external events is perceived to be j 11 larger, far larger than the risk from internal events, and the f l
| |
| 12 dominant ocntributor to risk is blackout type events, which 13 would happen with 25.6g range, as compared to the .3 SSE.
| |
| ( 14 [ Slide.)
| |
| l 15 In our assessment, as we show, the person rem from a .
| |
| 16 number of sequences are very similar. But that whole exercise 17 is critical to source terms, it's critical to pool bypass 18 which we think would suppress the space by req'uiring that i
| |
| 19 kgnitors be installed on the package supply.
| |
| l I
| |
| 20 I'd like to point out in site characteristics we use L 4
| |
| , 21 the Shippingport site, and that, in some people's minds, is a i
| |
| 22 pessimistic site, j i
| |
| ! 23 MR. MOELLER: Excuse me. When you list source term (
| |
| j 24 values, are you meaning what comes out of the current [
| |
| l t
| |
| [s -
| |
| 25 research? Or what do you meant
| |
| | |
| 117 1 MR. ROSENTHAL: Our cost-bonofit analysis was based s 2 on what we consider BNL or BNL staff high range values. They 3 were extracted from BMI-24 and other documents. Subsequently 4 we ran the code suite ourselves to see where we sat relative 5 to those estimates that had to be made two years ago in order 6 for me to be standing here today.
| |
| 7 But this is essentially a new source term picture, 8 and one would get other results if one were to use old source 9 terms. I think we were judicious in use of the new source j 10 terms. For example, in pool scrubbing you can see that the 11 pool scrubbing is a function of the particle size distribution 1
| |
| 12 and goes through quite a valley. We centered the distribution 13 of the particles coming into the pool at the minimum value 14 with a fairly tight distribution. So we calculated a .
| |
| 1 15 scrubbing factor of 6 to 60.
| |
| 16 GE likes to use values of 600 or 10,000. So I think I
| |
| i 17 I can only come down.
| |
| J 18 MR. SHEWMON: Is there any reason for doing that?
| |
| I l 19 You could have just arbitrarily thrown in a factor of 100 and [
| |
| i 20 gotten the same results, couldn't you? You said you i
| |
| 1 21 arbitrarily took your distribution so it would be at the i
| |
| 22 minimum.
| |
| 23 MR. ROSENTHAL: Yes.
| |
| j 24 MR. SHEWMON: What's the basis for doing that 25 instead of just saying we will derate things by a factor of i
| |
| l i
| |
| I l
| |
| | |
| 118 1 100 arbitrarily? Dorato the pool scrubbing. Is thoro any 2 basis for doing that outside of you are now proud because b
| |
| O 3 you've thrown an arbitrary factor of 100 into it, or what?
| |
| 4 MR. ROSENTHAL: By doing what we did?
| |
| 5 MR. SHEWMON: yes.
| |
| 6 MR. ROSENTHAL: We have narrowed the range 7 discussion down to what is the particle size distribution into 8 the pool. And you have to say, do you know it and will you 9 over know it, and not hide it behind other issues such as 10 scrubbing in the pool 11 We had a great debate with.GE. The advantage of 12 doing it is get up here and at least explain what I did and 13 where those conservatisms may come from, rather than hiding it 14 behind 20 values of parameters --
| |
| 15 MR..SHEWMON: The answer to my question is there's 16 no justification but you focused the conservatism this way.
| |
| 17 Is that it$
| |
| 16 MR. ROSENTHAL: Yes, sir.
| |
| 19 MR. SHEWMON: Would you tell me why Shippingport is 20 considered a pessimistic site?
| |
| 21 MR. ROSENTHAL: Because it's located close to 22 Pittsburgh.
| |
| 23 MR. OKRENT: But when you go out over long 24 distances, the Staff has frequently said most of the eastern 25 U.S. looks'the same when you're comparing man rom. So I'm not l
| |
| l i
| |
| | |
| 119 l
| |
| 1 quito ouro what that means, i 2 Paul, I might note that to the extent that we have i N" 3 reviewed pool scrubbing, we did some of it but it was not 4 something we devoted primary attention to. The one area 5 where I think our consultant raised questions was how well did 6 one know particle size and so forth.
| |
| 7 And if you were to try to say that the pool 8 scrubbing was good for a factor of 1000 or 10,000, it forces 9 you to look that much harder and you are that much certain J
| |
| 10 that you are not bypassing; you're claiming a huge factor.
| |
| 11 There is some kind of a tradeoff network to it.
| |
| 12 MR. ROSENTHAL: The technology is just not there on i 13 the back end reviews to derive central or mean values and
| |
| ) 14 distributions. When one looks at condational consequences 15 directly with what we perceived as at least high values, you 16 can get a perspective of what dominates the risk or doesn't, 17 and what the effect of having under-estimated or 18 over-estimated one sequence or another.
| |
| i 19 What I have attempted to do is to argue that our 20 risk perspective is insensitive to a great degree to the way
| |
| ; f-
| |
| ) 21 that we get to core melt and to the absolute values of those, i
| |
| 22 of core melt.
| |
| 23 MR. OKRENT: Are there other questions for 24 Mr. Rosenthal?
| |
| /'') 25 MR. REMICK: I have one. One the one slide you had i
| |
| | |
| 120 1 conditional consoquencos, then you had probabilitios at the '
| |
| t 2 end. Those were probabilities of what? Do they include the t 3 probability of core melt? Probabilities assuming a core melt? l 4 [S11de.3 5 MR. ROSENTHAL: Here is the probability of a core i
| |
| , a 6 melt, probability of a 1 TL3. The probability of an ATWS, and ?
| |
| 7 here is the consequences. ,
| |
| 8 MR. REMICK: Okay. Thank you. ;
| |
| 9 MR. OKRENT: Those numbers are with seismic or f 10 without? j
| |
| ' 11 MR. ROSENTHAL: Yes. Let me point out that with'
| |
| {
| |
| j 12 seismically qualified igniters, you shift the I to the El and 13 what we call the El max into that L3 category. f i
| |
| 14 MR. OKRENT: In the SSER-4 -- {
| |
| f i i 15 MR. ROSENTHAL: These slides are extracted from the 16 SSER; they are just copies. ;
| |
| 17 MR. OKRENT: On page 15-48 there is something called j 18 a base case which says without UPPS you get one times 10 to 19 the minus 4, and with UPPS, 6.7 times 10 to the minus 5 I 20 although here you don't show a big difference. l 21 MR. ROSENTHAL: I'm having trouble responding to ,
| |
| 22 you. l t
| |
| 23 MR. OKRENT: Tha 5 1 right. It's not important 24 now. You might take a look at page 15-48 later and comment. {
| |
| 25 Don't try to do it now. ,
| |
| i m
| |
| ---,m g , - - - - - . p
| |
| | |
| 121 1 MR. ROSENTHAL: I just want to make the point that 2 we have defined performance not in terms of pressures and
| |
| >O 3 temperatures but in terms of releases to the public and l
| |
| l 4 consequences of those releases. And that's why I keep l 1
| |
| 5 focusing on the conditional consequences of core melt.
| |
| 6 MR. OKRENT: Mr. Chairman, we might see what 7 General Electric would like to add to this discussion and then 8 break for lunch.
| |
| 9 MR. WARD: Okay, We have used I think about 35 10 percent of the time allotted. Where are we on the agenda?
| |
| 11 MR. OKRENT: Unfortunately, on the agenda we picked 12 up only 1 and part of 2.
| |
| 13 MR. SCALETTI And 4, 5 and 6, as far as the Staff 14 is concerned.
| |
| 15 MR. OKRENT: 5, yes I think. And 4 we haven't 16 discussed I would say. 6 the Staff has discussed.
| |
| 17 MR. SCALETTI Could I make a comment on 4?
| |
| 18 MR. OKRENT: I'm sorry, let's hold it.
| |
| 19 MR, SCALETTI: I was just going to say the Staff is 20 not prepared to discuss it. The safety goal is not Staff 21 policy; it's only a proposal and we are not in a position to 22 discuss it 'anymore than we have. It will be discussed on 23 10/9/85 with EDO.
| |
| 24 MR. OKRENT: He's telling you you may save 9 to 14 25 minutes there.
| |
| I W 9 v "
| |
| | |
| 122 1 MR. WARD: Is there a moan or a median thoro?
| |
| , 2 [ Laughter.]
| |
| 3 MR. OKRENT: One minute to tell us that we're not 4 going to talk about it.
| |
| 5 I would suggest we hear what GE wishes to add on 6 Item 2, and then break for lunch.
| |
| 7 MR. WARD: All right.
| |
| 8 MR. SCALETTI: This will be Dr. Debbie Hankins.
| |
| 9 MS. HANKINS: This should be very short. I only 10 have three slides.
| |
| 11 [ Slide.]
| |
| 12 This is simply a summary of our consequences and 13 risks for internally-initiated events. We were asked what are 14 those consequences most sensitive to. We did a sensitivity 15 study on the back end of the PRA and found that it is 16 relatively insensitive to core heatup, hydrogen generation, 17 primary system retention whether the RPV fails early or they 18 actually melt through the head, and the concrete composition 19 limestone facility.
| |
| 20 At different times with the subcommittee and the 21 full committee, we have presented those results. The risk is 22 moderately sensitive to assumptions regarding the late release 23 of tellurium. This is primarily for the full bypass sequence
| |
| { 24 as to whether or not you have a high population site.
| |
| l 25 Obviously the consequences in the man rem are going to be
| |
| | |
| 123 1 proportional to the number of peoplo that you havo out thoro.
| |
| 2 The more people you have, the higher the consequences, and of O- 3 course, assumptions relative to suppression pool scrubbing.
| |
| 4 I think that is very consistent with what Jack 5 Rosenthal presented on areas of importance.
| |
| 6 [ Slide.3 7 Relative to external events, seismic fire and flood, 8 the biggest contributor obviously was seismic in terms cof 9 external events. The areas that are most critical are, of 10 course, seismic hazard curve, and we have had a lot of 11 discussion about seismic hazard curves, and secondly, pool 12 bypass potential because with seismic events you introduce new 13 potential containment failure modes, possible structural p-( 14 building failure modes, the reliability of isolation valves 15 and the probability of drywell failure. This is simply 16 repeating what the Staff has said.
| |
| }
| |
| 17 MR. REMICK: Question. On your risk, what assumption 18 do you make about the site we use? Do we use Shippingport 19 also?
| |
| 20 MS. HANKINS: I'm glad you asked the question 21 because I did want to say something about that, We used Site 22 6 of the Reactor Safety Study. The reason we used that site 23 was because in doing a number of consequence calculations, 4
| |
| 24 that site is very average in terms of meteorology and, 25 population distribution, so for a given release of fission I
| |
| I l
| |
| _ _ _ ._, . _ . . . . . . _ _ . , . _ _ , . _ . _ . _ , _.. _ . ,. ~
| |
| | |
| 124 1 products, you got an avorego consoquenco result, ocmperod to 2 doing that same release over a wide variety of sites. So we O 3 use Site 6 because we wanted a best estimate representation of 4 the GESSAR II risk.
| |
| 5 Staff chose to use the Shippingport site. As I 6 mentioned, the consequences are very sensitive to -- in fact, l 7 they are linear with site population. I would like to read to [
| |
| 8 you from SER 2 since this question came up yesterday of how 9 does Shippingport rate with other sites, and SER 2 states this ;
| |
| 10 site possesses a greater surrounding population than 90 f 11 percent or more, and I would argue that we are talking high ,
| |
| t i
| |
| 12 90s when we say 90 percent or mere. Maybe the worst site of t
| |
| i 13 the existing nuclear plant sites in the United States.
| |
| 14 So the consequences that have been presented by the 15 Staff represent about as had as you can possibly get in terms i
| |
| 16 of siting a nuclear plant, and so when comparisons are made ,
| |
| i 17 with latent fatalities and risks calculated by G.E. for the
| |
| ; i 18 GESSAR design versus the Staff calculations, one has to keep r
| |
| i 19 in mind there is a tremendous difference just due to the site ,
| |
| 20 assumptions. It's not so much argument about containment 21 failure, about suppression pool scrubbing; there is a large v
| |
| I 22 contribution there due to site, and I think we have lost that j 23 many times in our discussions. I would just like to bring it ;
| |
| 24 back. {
| |
| t 25 MR. REMICK: Do you happen to know if Site 6 is i t
| |
| I
| |
| ( i
| |
| | |
| 125 1 typified by any particular plant sito that oxists?
| |
| 2 MS. HANKINS: It is a plant, eastern Atlantic O 3 coastal plant site.
| |
| 4 MR. EBERSOLE: What sort of numerical ratio are you 5 talking about?
| |
| 6 MS. HANKINS: At least an order of magnitude.
| |
| 7 MR, OKRENT: That's curious, in the following 8 sense. I have never done these consequence calculations 9 myself, but I have heard the Staff say orally and in writing 10 more than once when they were talking about siting that for
| |
| : 11 eastern sites, let's say east of the Mississippi, for latent l
| |
| 12 effects they find it hard to see more than a factor of 2 13 difference.
| |
| \ 14 MS HANKINS: For the majorit of sites, that's 15 true. For the majority of sites, they usually leave out the 16 ones that are on the extremes, and Shippingport is an extreme.
| |
| I 17 MR. OKRENT: I must say they did not put in -- well, 18 Beaver Valley is not very far from Shippingport, so I would 19 understand them making the statement if -- I will just leave 20 it at that. I remain in a state of disarray with regard to 21 just what the facts are, if there are facts.
| |
| 22 MS. HANKINS: I think one of the most useful 23 comparisons that could have been made, and was not made, 24 unfortunately, was to show the results with only changing the 25 site. We did that for the six sites in the Reactor Safety 5
| |
| - - - . , , - - - - , -.. - - - - , . , . , , - - , - - - , - . - , - . ~ . , , , - - , -
| |
| | |
| ~ - - --
| |
| 126 1 Study. Wo showod the rango thero. Dut it would havo boon 2 nice to show the difference between just Site 6 and 3 Shippingport. I think that would have been good information, i 4 Unfortunately, neither G.E. nor the Staff did that i 5 calculation.
| |
| 6 In summary, the areas of major uncertainty in terms r 7 of both internal and external event consequence analysis were, t i
| |
| 8 again, the seismic hazard curve, the component and structural i
| |
| J 9 fragilities, particle size distribution that you just talked [
| |
| 10 about relative to suppression pool scrubbing, and, of course, j
| |
| 11 human error assumptions. t 12 MR. OKRENT: Would Shippingport these days exceed ,
| |
| i 13 their 500 people per square mile thing and be excluded?. !
| |
| ('~) i
| |
| \ s/
| |
| % 14 MS. HANKINS: I would have to leave that to the l T
| |
| 15 Staff. j l
| |
| 16 MR. OKRENT: Or Beaver Valley. In other words, does ;
| |
| 2 i 17 Beaver Valley fall above or below your 500 people per 'quare 18 mile curve?
| |
| ! t l 19 MS. HANKINS: We built GESSAR there. i 20 MR. REED: I don't know that explicitly. What I f 21 would recommend to put this in context is that what we used i :
| |
| 22 was NUREG-CR/2239, which compares all of the sites together {
| |
| t 23 and you can get rankings from them, and Beaver Valley and !
| |
| )
| |
| L 24 Shippingport are essentially the same, and they are virtually j f
| |
| 25 always bridesmaids and never a bride. They are always in the !
| |
| \_ l t
| |
| I f
| |
| i i
| |
| .,e -
| |
| , , . - - - . , - - - - - - - , ,-,,-e,- - - , -
| |
| | |
| 127 1 top deson or so as far as a measure of badnoso is concernod, 2 but they are never really the worst.
| |
| O 3 We were trying to match as close as possible the 4 85th percentile, which was my instruction, to f i n'd a site that 5 did that, and I think we succeeded.
| |
| 6 MR. OKRENT: I will say this once more. When some 7 years ago there was a discussion of should the Staff consider r 8 more remote siting east of the Rockies, for a while they 9 seemed to be thinking that way. Then somebody came in with a 10 study which said, gee, when we do calculations of latent 11 effects, we can't get more than about a factor of 2 difference 12 among all the sites then in use, I have to assume, or at least 13 all of the sites that would not exceed this 500 per square 14 mi14 thing, implying that it was the number of people that 15 were 30, 40 and 50 miles away that was important, and that 16 tended to be similar for those sites.
| |
| 17 MR. REED: That is correct.
| |
| * 1 18 MR. OKRENT: If that is correct, then I will remain 19 confused.
| |
| 20 Okay, go ahead.
| |
| 21 MR. WARD: Is that it?
| |
| 22 MR. OKRENT: Yes.
| |
| 23 MR. WARD: Well, we are right on target then, 12:30, 24 right?
| |
| 25 MR. OKRENT: If that is when lunch was supposed to
| |
| | |
| 128 1 be, then we are on targot.
| |
| 2 MR. WARD: Yes, that was it, and we have an hour and 1
| |
| 3 40 minutes for this afternoon -- an hour for lunch, and an a
| |
| 4 hour and 45 minutes for GESSAR. i
| |
| ; 5 MR. OKRENT: I am assuming we may be running an 6 extra half-hour.
| |
| 7 MR. WARD: We don't really have that much !
| |
| 4 a
| |
| 8 flexibility, Dave.
| |
| i I'- !
| |
| . 9 MR. OKRENT: We can't run late? '
| |
| ' I 10 MR. WARD: I guess we can, but we are already 11 scheduled for 6:45, so we have to be realistic. ,
| |
| I l
| |
| i 12 Okay, let's break until 1:30.
| |
| l 4
| |
| 13 [Whereupon, at 12:35 p.m. the meeting was recessed, i
| |
| 14 to resume at 1:30 p . ra . the same day.) {;
| |
| 1 15 !
| |
| j i 4
| |
| l 16 , l 4
| |
| 17 !
| |
| i 18 !
| |
| l I 19 !
| |
| i 2a !
| |
| l I' 21 i
| |
| : j. 22 f i
| |
| i 23 24 )
| |
| 25 l i l, 8
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| ; I 1 !
| |
| f
| |
| | |
| 129 1 AFTERNOON SESSION 2 [1:30 p.m.3 b
| |
| -- 3 MR. WARD: Let's return to the discussion of GESSAR. I 1 MR. OKRENT: The next agenda item relates to 5 interface requirements. I should note that there appears to 6 be something like one would assume was the normal kind of 7 interface requirement documents in existence that GE has
| |
| {-
| |
| 8 prepared.
| |
| 9 What is less clear is the extent to which interface 1
| |
| 10 requirements will impose some kind of a requirement that the 1
| |
| 11 systems involved will have the performance reliability, 12 whatever is assumed in the PRA.
| |
| 13 If it turned out, for example, the service water
| |
| ( ,) 14 system in the ultimate heat sink, which is part of the 15 balance-of-plant, were really very unreliable, this would 16 affect one's concausions that one heard earlier, and so some 17 -- in fact, many of the kinds of conclusions that the Staff is 18 drawing and GE are based on some assumptions concerning 19 performance in the balance-of-plant. And we thought it was 20 relevant to see to what extent, in fact, there existed any a 21 kind of quantitative requirements, and if so, what was their 22 nature, et cetera. And so we will hear something about that.
| |
| 23 I guess we will hear from the NRC first, and then 24 from GE. Hopefully, it will be direct and to the point.
| |
| ; 25 MR. SCALETTI Dino Scaletti from the NRC Staff.
| |
| | |
| .- . - . - . _ - , __. -_ ~ .- - .
| |
| 130 i Lot no just quickly stato -- and I will bo to the 2 point -- the reason for interfaces is due to, the application s) 3 for GESSAR 11 is for a design which does not include a total 4 nuclear plant. Therefore, interfaces are required.
| |
| I 5 Documentation and interfaces are required to assure the Staff 6 6 that the requirements of the Standard Review Plan and the NRC 7 regulations will be complied with at the time an application 1
| |
| 8 comes in.
| |
| 9 Also, as part of this, the Commission's Severe
| |
| ] 10 Accident Policy Statement, which sets forth the requirements 11 for a severe accident review, these also require that the 12 Staff document and also that GE document certain interface i
| |
| 13 criteria to make sure that this policy is complied with at the 1
| |
| 1 14 time that an application would be submitted.
| |
| i i 15 I have mentioned in the past -- and we have i 16 discussed this issue of interfaces in the past with the full 17 committee and also with the subcommittee -- the interfaces, 18 from the Staff's standpoint, that they have required of GE for i
| |
| 19 the GESSAR design, believing that these were additional 20 interface requirements were necessary to fulfill the 21 requirements that I had mentioned, are identified in Section
| |
| 't 22 1.10 of the SSER, the SER, and all of its supplements.
| |
| 23 I had compiled a list for the subcommittee meeting.
| |
| i j 24 I guess I somewhat misunderstood the context of Dr. Okrent's i
| |
| 1 l 25 question when I wrote it down last night at the conclusion of I
| |
| 1 l
| |
| )
| |
| l
| |
| . -~ -. . _ _ _ . _ ~ _ . _ . . . _ _ _ . . . _ - _ . . - , _ _ . --.
| |
| | |
| _ - = - - - . . . .-. .-- - -.-
| |
| 131 1 the subcommittoo mooting. I do havo a copy of it that I could i
| |
| 2 give you here of what we passed out last night. This j
| |
| '' identifies the severe accident interface, where it is located 3
| |
| 4 in the SER, and also if there is a quantitative requirement 5 related to that interface.
| |
| 6 MR. OXRENT: I'm really a little bit miffed at any 7 misunderstanding. We had been trying for a few meetings to i
| |
| 8 ascertain, are there quantitative requirements, and if so, 9 what they are, and you were specifically advised that we were 10 not looking for a long list of places to loon where we might 11 find something.
| |
| 12 MR, SCALETTI. Dr. Okrent, that's what I gave you 13 last night, was wherever they were. I excerpted the portion
| |
| ) 14 of the SER and included it under the interface identified in 15 the list that I had given to you.
| |
| 4 16 MR. OKRENT: Mr. Denton is interested in expediting I
| |
| 17 this review, and if you can't provide us with the specific 4
| |
| 18 information as to whether and what the quantitative 19 requirements, if any, are of the Staff, we will wait another 20 meeting.
| |
| i
| |
| ! 21 MR. SCALETTI Dr. Okrent, I gave you that list i
| |
| 22 and identified the requirements, as they were specified,
| |
| ! 23 M R .- MICHELSON: Could we have a copy of what he gave 24 yout i i don't hav. anything. I'm sorry.
| |
| 2s MR. OxRENT:
| |
| (])
| |
| | |
| 132 1 MR. MICHELSON: Ho said he gevo you a list. I'd 2 Ikke to see the list.
| |
| 3 MR. OKRENT: I have no list, There's a song, "I 4 Have a Little List," but that wasn't my song.
| |
| 5 MR. SCALETTI. The list was passed out at the j 6 subcommittee meeting yesterday.
| |
| 7 MR. MICHELSON: That list. That's not really any
| |
| ?
| |
| 8 help at all.
| |
| 9 MR. OKRENT: Is that all the Staff has at this time 10 on the subject?
| |
| I 11 MR. SCALETTI- Unless you have some questions, l
| |
| i 12 MR. MICHELSON: I have a question, As an example, 1 j 13 was trying to search out real quickly the one that Dr. Okrent 14 gave, the example Dr. Okrent cited, although I was looking at 15 it earlier this morning, and that is the service water system, i 16 just to see what is said in the OESSAR !!, what is said in the l
| |
| 17 SER, and so forth.
| |
| j 18 All I could find -- but perhaps GE could correct me 19 and tell me where I should have looked -- ! looked in Chapter 20 9. I looked at page 9.2-4, and in there it says that the 21 Applicant is to provide a description of the service water i
| |
| 22 system outside of the nuclear island, the ESW flow rates, and I
| |
| 23 establish interface requirements for the BOP. Then they give
| |
| ! 24 the table where the flow requirement is prescribed. That's 25 all GESSAR seemed to say about the emergency service water in i
| |
| | |
| 133 1 terms of Applicant's requirements, f
| |
| 2 It also reference 9.2-5 for a description, and I 1
| |
| 3 went to 9.2-5, and it said that the Applicant will supply 4 that. So that was not any help.
| |
| 5 So then I went to your SERs and looked at the 6 Interface Section, 1.2 I believe it was, and all that is is a 7 list of the systems that might have interfaces, and service l
| |
| 8 water wasn't even listed. But I might have missed it. I was 9 looking at Table 1.2.
| |
| $ 10 So that didn't help much, so I went to the SER I 11 section dealing with service water, and it just says, yes, the
| |
| ; 12 Applicant is going to do some things.
| |
| 4 13 But I'm searching to where is -- did you ever even 14 see an interface document on service water, and if you did, 4
| |
| 15 where did you reference the review of it?
| |
| 16 MR. SCALETTI: Table 1.9 of GESSAR should identify ,
| |
| i l 4
| |
| L 17 -- not the SER now -- Table 1.2, I believe, in the text, it i 18 says that not all of the -- this is the table that exists i
| |
| j 19 that's two and a half pages long of identified interface I
| |
| ! 20 items. It is not totally inclusive of all of the interface
| |
| . t 21 items on GESSAR II. The complete list from the standpoint of i
| |
| 22 General Electric is provided in Section -- I believe it's 1.9 i
| |
| 23 of GESSAR. I 4
| |
| i ;
| |
| 24 MR. MICHELSON: It wasn't on your Table 1.2, and 4
| |
| 25 it's a pretty important system, probably one of the most i i L
| |
| l I 1 i i
| |
| | |
| 134 1 important systems. I 2 MR. VILLA: Maybe I can clarify. I went back, 3 because we had this discussion yesterday, and I went back to j 4 San Jose last night by phone and checked specifically the 5 emergency service water, and I found that it was easier to t
| |
| 6 deal specifically with Section 9 in the SER, the same section i
| |
| 7 that you were looking at. And in the SER, and after 8 discussing with some other people, the requirements for the 9 emergency service water are listed in the General Electric 1
| |
| 10 document, and they include such things as heat loads, flow 11 rates, design pressures, temperature of the piping, chloride 12 content, and reliability.
| |
| 13 MR. MICHELSON: How is that document at all tied 14 into GESSAR II or into at least the SERT is there a path --
| |
| 4 15 see, I was told earlier by the Staff, and you agreed, that all
| |
| , 16 I ever need to look at is GESSAR II and its amendments plus 17 the SER and its amendments, and that's all I'm going to look 4
| |
| 18 at.
| |
| 19 If it isn't somehow referenced in there, then I have 20 to assume it doesn't exist, even though you say it does, and 21 that's fine. It certainly ought to.
| |
| 4 22 MR. VILLA: If you l o o ,k at the same set of 23 information, if you look in Table'9.2-1 of GESSAR --
| |
| i 24 MR. MICHELSON: I put it back on the shelf 25 MR. VILLA: I have it -- which I believe at first J
| |
| | |
| 135 1 glanco may be a typographical orror in the SER, becauso it 2 mentions Table 1.1 instead of 9.2-1 -- I'm sorry -- it's 9.1-1 O
| |
| V 3 in the SER, and I have in front of me 9.2-1, which begins 1 1
| |
| 1
| |
| ; 4 " Essential service water," listing heat loads, flow rates, et 5 cetera.
| |
| s 6 MR. MICHELSON: But that's not -- it doesn't even i f
| |
| i 7 1kst or mention or reference your interface document. I 8 assume that that table in the FSAR applies all right.
| |
| I 9 During all of our subcommittee meetings, we kept i
| |
| j 10 saying, "It's in the interface document," and I said, "Well,
| |
| ; 11 have you reviewed the interface document, and how do I know"
| |
| ! 12 and so forth, and we never got a halfway decent answer, even 13 until today, and now I've got the answer is, "If it isn't in 14 the document you're looking at, then it doesn't help."
| |
| q 15 I'm confused.
| |
| 16 MR. VILLA: Let me say, in the table are also lists l
| |
| 17 of all of the applicable document numbers that define the i
| |
| ; 18 design of each component of the system.
| |
| I 19 MR. MICHELSON: Document numbers? You mean
| |
| . 20 specification numbers?
| |
| i l 21 MR. VILLA: Right. What we call a master parts
| |
| * 22 list.
| |
| 23 MR. MICHELSON: A master parts list includes a spec.
| |
| i 24 MR. VILLA: It includes a whole pile of information.
| |
| 25 MR. MICHELSON: That's Table 9.2-1. That's the one i
| |
| i I
| |
| i i
| |
| n .,--w. - -.n ~ ,- - -.. ~.--,-- ,,--, -,
| |
| , . , . - - - . - - , , , - - ~ . , --
| |
| | |
| . . _ . - ~ . . -. -. , , .._= - . - . - , - . . _ . - - . _ ~ .
| |
| 1 136
| |
| ?
| |
| ! 1 I nood to lock at.
| |
| l 2 MR. SCALETTI: -There is also in Table 1.9-24 --
| |
| l 3 Table 1,9-24, which has yet to be amended, to the GESSAR II i 4 document, which is a severe accident interface with regard to ,
| |
| I
| |
| )
| |
| 5 the emergency service water system.
| |
| l 6 MR. MICHELSON: Could I see a typical page?
| |
| -7 MR. VILLA: Yes. I just picked it up.
| |
| 8 [ Document handed to Mr. Michelson.3 1 9 MR. MICHELSON: Where is this master parts list? I
| |
| , t
| |
| !' f 10 thought that was an equipment number as a drawing reference I 11 and not as a master parts list number. Then I was mistaken?
| |
| j 12 MR. VILLA: I am most familiar with the ones that 1 i l !
| |
| 13 begin with the GE system, which is a letter and a two-digit [
| |
| i I
| |
| ; 14 number and a dash. [
| |
| 15 MR. MICHELSON: So I am to assume, since this is in !
| |
| [
| |
| , 16 GESSAR II, the Staff went through and sampled as they wished, I h
| |
| l 17 these equipment numbers and the documentations associated with l
| |
| ?
| |
| i 18 them under that number. Is that right? f i
| |
| 19 MR. SCALETTI: If it's in GESSAR 11, that's correct.
| |
| j 20 MR. MICHELSON: So if I picked two or three of these
| |
| {i 21 number and go back, somewhere in your files is a piece of [
| |
| paper that shows that you have it and whether or not you i
| |
| ! 22
| |
| ! i 23 looked at it? l
| |
| [
| |
| 24 MR. SCALETTI. I can't answer that. {
| |
| l 25 MR. MICHELSON: Isn't that the orderly way? [
| |
| t f
| |
| I I
| |
| l f
| |
| _,___-_,__._..___--I
| |
| | |
| 137 1 MR. SCALETTI: I wnuld assumo, yos. I would have to 2 check with the reviewer of that information.
| |
| I N
| |
| 3 MR. MICHELSON: If these are indeed GE part numbers, 4 I'm acquainted with the documentation that goes with those, l 5 and this would be adequate. I didn't interpret " equipment 6 number" that way.
| |
| 7 MR. VILLA: Do you want to hear anything else from GE 8 on the subject?
| |
| 9 MR. OKRENT: I would like to have GE tell us what 10 quantitative interface requirements are included in the i
| |
| ]
| |
| 11 interface requirements, and please don't refer me to pages and 12 so forth.
| |
| I 13 What are the specific values for what systems?
| |
| ! 14 MR. VILLA: I can give you specific values for the 15 emergency service water system. For example -- not all of 16 them; I just don't have them -- one example is, on some I ,
| |
| 17 piping, we have a 150 psig limit at 150 degrees Fahrenheit 18 That also is listed here in OESSAR.
| |
| 19 On the chilled water systems, to pick up another l
| |
| 20 question that Mr. Michelson asked yesterday, we require a 70 21 db notch test at 40 degrees Fahrenheit in accordance ASME 22 Section 3 for all pipes smaller than two and a half inches 23 thick. And for pipes greater than two and a half inches 24 thick, we require the service water temperature minus 100 25 degress Fahrenheit.
| |
| l
| |
| | |
| 1 138 4
| |
| f 't I have to coeroh for moro numborn if you want to soo 2 them.
| |
| I x
| |
| , 3 MR. OKRENT: I thought you said there were some 4 reliability numbers. It was either performance -- by 5 " performance" I mean availability, reliability, this sort of 6 thing, things that enter into the PRA.
| |
| 7 MR. VILLA: Kevin Holtselaw will answer that 8 question.
| |
| 9 MR. HOLTZCLAW: After we completed the PRA study, in 10 order to respond to the concern of how do you make the PRA 11 become a reality as far as the construction of the plant goes i .
| |
| I !
| |
| i 12 and construction and operation of the plant, we identified j 13 additional interface requirements, which specified such things 14 as re11 abilities that were assumed in the PRA for areas 15 outside of GE's scope and that would make that incumbent on an 1
| |
| ! 16 Applicant referencing the 0,ESSAR !!, to verify that his 17 balance-of-plant design met those reliability targets that 18 were ut111:ed in our study, or provide alternative studies 19 that would show that, given a reliability estimate for one of l 20 his supplied systems, it would be acceptable from the 21 standpoint of meeting the bottomline results of the GE PRA j 22 study.
| |
| I 23 MR. OKRENT: Could we have -- do you have a copy of 24 the document that gives that? Has something been filed? !s l
| |
| l 25 it a part of OESSAR II? It's not clear to me. l 1 '
| |
| l 1
| |
| i
| |
| | |
| 139 1 MR. HOLTZCLAU: I don't havo a copy of the document
| |
| : 2 with me, Dr. Okrent. We did supply it to the Staff on the i
| |
| i 3 GESSAR docket.
| |
| 4 MR. SCALETTI It's dated July 13, 1984, and this i s i 5 the document that I alluded to a moment ago that will be 6 amended to Table 1.9 of GESSAR. I have a copy of it here, if i 7 you would like to look at it. It covers additional table I I 8 entries for actions and considerations on GESSAR.
| |
| 9 MR. OKRENT: I think it would be helpful to make a 10 copy available to Mr. Major, so he could Xerox copies for the I
| |
| ! 11 members of the committee, and we can see what it is and go on 12 to something else temporarily.
| |
| 13 MR. MICHELSON: I have a follow-on question. Just 14 to make sure that it doesn't slip away - . - and remember now, l
| |
| 4 15 looking at the table this morning in the FSAR -- and what I 16 didn't find in there was those devices that belonged to the 17 scope of supply of the Applicant. There are no master parts l
| |
| i 18 lists, numbers, or anything else listed, because you haven't i 19 oven -- I went to the flow diagram, and you just say what is 1
| |
| 20 coming from the Appiteant. I don't think there's anything on l
| |
| 21 any devices. That lists covers the flow diagrams, but I don't i
| |
| (
| |
| 22 think it covers the balance-of-plant part 23 MR. VILLA: For example, Document No. E-12-B001, j 24 which defines the design of the Archer heat exchanger, does 25 two things. Number one, it references an interface f a
| |
| i i
| |
| ,c., -,---,-,+,-y _. , , . , _ , ,. , _ - , , . , , , - . . - . . , , _ . . . . _ _ - , ._.,,..,,-_mr-_,_ _,r-.g-..-r..w-_.- y-,,.e-_-r_,r--w .
| |
| | |
| 140 1 roquircmonto documont --
| |
| 2 MR. MICHELSON: You mean, if I go to that document i
| |
| 3 that is referenced here, I will find another document t
| |
| 1 4 referenced? Is that --
| |
| 1 L
| |
| 5 MR. VILLA: Not just one, you'll find many.
| |
| 6 MR. MICHELSON: I'm interested, as another point, do 1
| |
| 7 we chase every conceivable document that's referenced as we 4
| |
| I j 6 work down the road, and all of those have been covered by NRC 9 as a part of your reviewt i
| |
| 1 10 MR. SCALETTI- I'm not saying every document has 4
| |
| 11 been covered.
| |
| l 12 MR. MICHELSON: You are taking responsibility for 13 auditing, if you will, every one of those.
| |
| J.
| |
| l
| |
| ,j 14 MR. SCALETTI: Be also assured that we looked at 15 Table 1.9, and the Staff reviewers who reviewed the various 16 systems that are required as part of their review of the !
| |
| 17 Standard Review Plan would identify those portions that are 18 missing. They would, in turn, look at that to make sure that 19 this was included as an interface, as I mentioned.
| |
| ; 20 MR. MICHELSON: So that covers ever reference that j 21 might be referenced in a reference. That's what he's citing 22 now. He's citing a reference in OESSAR which, in turn, 23 references some other document, and you are saying that you 24 have also chased that document, if you wished.
| |
| . 25 MR. SCALETTI: If we wished, we could chase the l
| |
| I i
| |
| i i
| |
| . _ _ _ . _ . _ - . . . - - _ _ _ -_ . , ~ , - _ _ _ _ . , , _ _ _ . . . _ _ . . - _ . . -
| |
| | |
| 141 1 documont.
| |
| 2 MR. MICHELSON: Therefore, it's a part of the FDA 3 approval.
| |
| 4 MR. SCALETTI: If it is so identified.
| |
| 5 MR. MICHELSON: That's a really encompassing package 6 of paper when yo's start going to the references of the 7 references. I didn't think you were doing that. If you are 8 going that far, I'm sure you're covered, because it's all 9 referenced in GE material somewhere, I'm sure.
| |
| 10 MR. VILLA: I think you have to recognize that, for 11 example, our document structure starts at a top level. There 12 are seven levels of documents in our structure, and it starts 13 with a small number, actually like maybe 200 items for the 14 NSSS.
| |
| 15 MR. MICHELSON: I am quite acquainted with GE's 16 system of documentation, because I was aware of how they set 17 that up, all right. I guess I didn't realize the Staff took 18 responsibility for all the references to the references as 19 well.
| |
| 20 MR. SCALETTI. I'm not saying we considered all of 21 them. I'm saying we are sure that the interface list is 22 adequate from the standpoint that the items have been 23 identified, that there are interfaces, and it's well 24 documented. This part of the review has not been completed 25 yet.
| |
| | |
| 142 1 As I said yostorday and I think porhaps beforo, the 2 interface items, the balance-of-plant and other interface L 3 items, will be reviewed at the time they come in with an 4 application, and they will be reviewed to the Standard Review 5 Plan that's in effect at that time.
| |
| 6 MR. MICHELSON: I thought they would just come under i
| |
| 7 the backfitting rule, though, and as long as they were I 8 described in the FDA somewhere, and you are saying even in 1
| |
| 9 references to references, then I thought those items, you
| |
| ! 10 could not go back and change.
| |
| I 11 MR. SCALETTI. That's not my understanding, no.
| |
| 1 12 MR. KERR: Mr. Chairman, I apologize for not having ;
| |
| 13 an appropriate background to appreciate this discussion. What
| |
| ; 14 is it we are trying to do here? It almost sounds as if we 1
| |
| ; 15 have concluded as a committee that we review every detail of '
| |
| i
| |
| , 16 the design. l 17 Since I don't think we do that, what is it that we j '
| |
| 18 are trying to do?
| |
| i i
| |
| 19 MR. MICHELSON: We're trying to identify the scope j i
| |
| 20 of the FDA approval, knowing which things now cannot be gone i
| |
| 21 back and changed without coming under the backfit rule and !
| |
| l 22 whatever, i i !
| |
| 23 MR. XERR: What does that mean, to identify the i i !
| |
| 24 scope? l f'
| |
| t l
| |
| 25 MR. MICHELSON: It means, what did the Staff approve l l ?
| |
| r e
| |
| i
| |
| | |
| 143 1 when they tocuod tho FDA? Chat doseription, what plant woro l
| |
| 2 they approving? There has to be a description of it.
| |
| \
| |
| 3 MR. KERR: So we want.a list of --
| |
| t 4 MR. MI CllEL SON : We want to know documents form the 5 basis of the FDA approval, and what were the limits of the FDA 6 approval?
| |
| i 7 MR. KERR: What will we do with that information 8 once we have it? ,
| |
| 9 MR. MICHELSON: Now we know what things to look at 10 in terms of our review. We don't look at limits of the FDA, 11 for instance. We also look to see that important things are 12 within the limits of the FDA review.
| |
| I i 13 MR. OKRENT: Can I give an example that might be i
| |
| l O)
| |
| \j 14 appropriate?
| |
| 15 MR. KERR: I don't know.
| |
| 16 MR. OKRENT: Let me try. There is an issue the 17 committee has concerning the Palo Verde Plant where the 18 auxiliary feedwater system was supplied by balance of plant.
| |
| 19 the venodr-proposed design did not have a feed and bleed 20 capability. He did say he, I think, in some way that he 21 espected the balance of plant to provide truly reliable 22 auxiliary feedwater system, but the system that was in fact i
| |
| j 23 supplied was the minimum that would pass the Statf*s recipe
| |
| ]
| |
| I 24 for calculating reliability.
| |
| i 25 So here was a case where you ended up with what some i
| |
| 1 4
| |
| | |
| 144 i
| |
| l 1 ocamittoo m3mbors ocnoidor o possiblo chartfall in combined ,
| |
| i 1
| |
| 2 capability. That is what the vendor supplied and the balance 3 of plant --
| |
| 4 MR. KERR: You are referring to a set of committee S standards. That's a different set than --
| |
| l l
| |
| 6 MR. OKRENT: No, 1*m saying there was not an i 7 interface requirement by the vendor --
| |
| 3 1 !
| |
| ! 8 MR. KERR: I recognise interface requirements are r i
| |
| 9 important -- i
| |
| ! i 10 MR, OKRENT: To a three-pump system.
| |
| 11 MR. KERR: It sounds as if we are somehow trying to ;
| |
| 12 get the list of everything that goes into a nuclear power [
| |
| t 13 plant, and since I know we are not trying to do that --
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| t 14 MR. MICHELSON: I'm trying to identify -- to cover ,
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| I i
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| 15 and identify what is covered by an FDA. Is it an open-ended [
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| I 16 approval or is it a closed approval? If it's closed, where 17 are the boundaries identified? We first thought maybe it was l J !
| |
| 18 even open ended, which would be unacceptable, and so we tried j 19 to and I think we finally got a definition of the boundaries, 20 which is that written statement that you have in front of you, i
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| lI 21 which is a good definition of the boundaries, !
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| r i
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| 22 I was just trying to search out to make sure, i i
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| l 23 though, I understood what those words meant, and they mean ;
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| t i'
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| 24 quite a bit more than just what is stated there because now it i
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| th. re,.r.n..s to th.
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| c:)
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| 2, m..n. th. ,ound.r,.s a,. ,eal,, ,n i
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| r 4
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| L 1
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| i
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| | |
| 145 1 roforensos, which moana I havo to do a lot of chasing to find 2 out how far they might have proved.
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| 3 That is fine. I just want to know where they are, 4 and I think I know. It is not that I necessarily think it's a i
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| 5 very good idea. I'm just trying to understand it.
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| 6 MR. SCALETTI: Did you understand what we identified 7 as interface is not Staff approval of the design that's coming 8 in in the future?
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| 9 MR. MICHELCON: If it is in the FDA, if it is a part i t
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| 10 of the FDA, if it's in OESSAR, et cetera, then I think you 11 cannot change, you cannot require a change of that design 12 without going through the backfitting rules. That's all I'm 13 looking at. So I know what is defined is what they will
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| : \% ,/ 14 supply. But you can't require more, and even if you never l
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| 15 looked at it and didn't realise it, you can't require more.
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| 16 I just wanted to, figure out the scope of possible 17 mistakes that can be made in review simply because there is an
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| , 18 enormous amount of material to review with limited resources, l
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| l 19 which I fully recognise. I'think you have defined a scope far 20 larger than you could ever possibly review.
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| I 21 MR. OKRENT: Could I get back to Item 3 and ask the T
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| 22 Staff if they have any quantitative interface requirements
| |
| ; 23 other than those that are on this General Electric table, 24 which I thought was being Xeroxed?
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| 25 MR. MAJORS: It is being Xeroxed.
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| l
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| }
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| )
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| t
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| - 146 1 MR. OKRENT: And which wo will rocoivo to look at 2 MR. SCALETTI-. Yes, and the list that I had given 3 you yesterday, and I believe you have a copy of now, there are ,
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| I I
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| 4 the interface requirements that fragilities of components be i 5 met identified in Supplement 3. We can call those out.
| |
| 6 MR. OKRENT: Are there others besides the ones on o
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| 7 fraDilities?
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| 8 MR. SCALETTI: There are some specific ones on l 9 aircraft strike, on hazardous materials. These are under the i
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| 10 SRP. There would be some specific requirements associated 11 with the CPML Rule.
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| 12 MR. OKRENT: Okay. Those are they, then, if I 13 understand it.
| |
| 14 All right. Well, I think at this stage --
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| 1 15 MR. SCALETTI: Excuse me. There will also be the 16 interface requirements or the FDA conditions associated with 17 upgrading a UPPS ten-hour station blackout capability, a 18 dedicated backup power supply for the ignitors, and a seismic 19 upgrade of UPPS.
| |
| 20 MR. EBERSOLE: May I ask a question as an example 21 here? In the OESSAR II, does the system preclude the case
| |
| ; 22 which occurred at River Bend where the third high pressure 23 diesel was, in fact, not independent but it got its service 24 water from the other two diesels? Does your system lock up a 4
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| 25 set of requirements that preclude that occurrence?
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| \
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| _=
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| 147 4
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| 1 MR. VILLA: Maybo I can answar that. I boliovo it 2 does.
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| U,s, 1 3 MR. EBERSOLE: I think it does, too.
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| i I
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| 4 MR. VILLA: Our design -- the service water design
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| ; 5 is clearly defined in GESSAR.
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| 4
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| { 6 MR. EBERSOLE: It's yours.
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| 1 7 MR. VILLA: Yes.
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| I 8 MR. OKRENT: Okay. I would suggest we go on to Item 9 7, time being what it is. We may want to come back to No. 3 10 later if there is time.
| |
| 11 Let me say with regard to the USIs and GSIs, the 12 subcommittee yesterday listened to the Staff comments on their l
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| 13 resolution, and leaving t r.e question of sabotage aside, we did 14 not go into station blackout or decay heat removal --
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| I
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| { 15 MR. EBERSOLE: Dave, on that particular item you are 16 talking really about another interface. You are talking about i
| |
| 17 Item 7 now? i 18 MR. OKRENT: Item 7. Let me introduce A43.
| |
| 19 MR. EBERSOLE: It is A43. It is an interface 20 requirement. I call out the fact they are using 21 hydrochlorides. They do not define the insulation and so 22 forth that would act as a contaminant, which these 23 hydrochlorides have to handle. It's a good example of the 24 absence of an interface.
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| I j 25 MR. OKRENT: That is one of the questions that
| |
| | |
| 148 i
| |
| i socmod to pornist during the cubecmmittoo mooting, and the 2 other question that seemed to persist was, as we understood it O 3 from the Staff, one of the bases for them saying that A43, 4 which you may or may not recall relates to problems of 5 blockage of the flow into the pumps that would get water from 6 sumps, was that the UPPS system would make it unnecessary to 7 use these systems and so therefore you didn't really have to 8 look that hard at how it was to be resolved.
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| 9 There was a further reason given, which was they 10 anticipated that for existing plants there would be no 11 hardware changes required. Maybe a notice alerting operators 12 that they should be aware of this potential, I guess sort of 13 like the Surgeon General's message.
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| 14 But anyway, with that background, what comments does 15 the Staff wish to add, or clarification on A439 16 MR. SCALETT1' I made a comment yesterday on A43 17 indicating that -- I guess I was a little bit too brief on 18 the reason for resolution. It is not strictly UPPS. We had 19 talked about -- although that is a factor, that is a 20 possibility. It is another way to get water to the core.
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| 21 There are other ways to get water to the core, too, that 22 follow a large break LOCA, which was the concern, that UPPS 23 was not designed to accommodate a larger break LOCA.
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| 24 We had talked scout oversize strainers and the 25 position of the RHR intakes within the pool. There is also a t
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| 4
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| | |
| 149 1 requirement on page 6.25 of the SER which relates to strainer
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| -~ 2 configuration, and demonstrating by a utility applicant that 3 the mesh of the strainers have the possibility of blocking out 4 a certain amount of debris and cannot be blocked by one piece 5 of large debris.
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| 6 G.E. has also committed to use a reflective type of 7 insulation in the primary system, which will reduce the 8 possibility of plugging the intake strainers. As I mentioned 9 before, the other ways to makeup to the core were the high 10 pressure core spray, I believe there is -- you will have some 11 time following a large break LOCA that your systems will not 12 be totally incapacitated and not be able to use, and we have 13 done some brief calculations which indicate that we would have O
| |
| k_s 14 probably approximately 25 minutes to a half-hour before you 15 would have to go to a system like UPPS.
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| 16 MR. EBERSOLE: I must have missed this. You say 17 G.E. has committed to reflective preliminary insulation?
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| 18 MR. OKRENT: That's correct.
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| 19 MR. EBERSOLE: Fine. That just about puts that to 20 rest.
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| 21 MR. OKRENT: Any other questions on this?
| |
| 22 [No response.)
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| 23 Let's go on to Item 8. Here the picture is in its 24 PRA G.E. examined internal flooding. When the Staff tried to 25 review this, certain difficulties. Insufficient information
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| | |
| 150 1 on the details of dosign, they say, modo it difficult for them s 2 to agree or disagree. I will let them use their own words.
| |
| U 3 MR. SHU: Calvin Shu from Brookhaven National 4 Laboratory. I would just like to take a couple of minutes t9 5 summarize the overall review process and some of the findings 6 that we have arrived at to give you a brief overview. BNL was 7 originally requested by the NEC to review the internal 8 flooding PRA submitted to the NRC.
| |
| 9 It was a limited review. We were asked to spend 10 about four man weeks to review the whole effort. So in the 11 process, we are not able to arrive at a new, independent core 12 damage frequency due to internal flooding events. We have one 13 round of questions with General Electric in which we tried to 14 seek clarification and additional information, and they did 15 provide a response to us.
| |
| 16 What G.E.'s s t u d i,e s essentially entailed was 17 examination of the different potential flooding areas based on j 18 the FSAR evaluations. Their flood-initiating frequency was 19 very low, in the order of 10 to the minus 6, 10 to the minus l 20 7, or lower, depending on the area. ,
| |
| I i
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| 21 What BNL did was review the initiating frequency, 22 and also we reassessed the potential flooding initiating 23 frequencies based on maintenance-induced floods and 24 rupture-induced floods. We would divide them into two broad 25 categories. There are flooding events inside the plant that t
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| | |
| 151 i
| |
| i could ccmo frca -- thrcughout the maintenanco procoss, 2 inadvertent openings in isolation valves and so on and so O 3 forth.
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| 4 Then on the other hand, there are also
| |
| - 5 rupture-related pipings and whatnot. We have assessed the 6 frequencies, and they are in the order of 10 to the minus 4.
| |
| 7 Also, as part of the review, we have identified blowout 8 opening that connects the RCIC room with the RHR room. This '
| |
| 9 is a little different than what G.E. has initially suggested 10 as to their complete independence of their rooms.
| |
| 11 We identified that there may be a potential leakage 12 path from the corridor back into the ECCS room if flooding 13 exceeds the 15-inch flood height. We did not pursue the 14 scenario to the ultimate in terms of identifying core damage
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| {
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| 15 contribution coming from these particular sequences; however, 16 we made an estimate using the following assumptions.
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| 17 If we assume that the ECCS rooms are indeed 18 independent, that there is no communication from one room to 1
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| 19 another, and also if we assume that whatever critical 20 components is within one ECCS room, if they got inundated by 21 flood would not affect the operation of equipment or 22 components in adjacent or other rooms, then we believe the 23 core damage frequencies will be low. By that I mean we 24 estimate it will be in the order of 10 to the minus 6, 10 to 25 the minus 7 or lower.
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| f l
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| 152 1 That in a nutsho11 is a briof summary of what we 2 have done for internal floods.
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| O 3 MR. OKRENT: Are there,any questions?
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| 4 MR. MICHELSON: Just for clarification, did you look 5 at the reactor water cleanup system break as part of your 6 study?
| |
| 7 MR. SHU: We have identified a number of different B types of lines, and that was one of the systems that we have 9 looked at; but again, in terms of initiating frequencies, we 10 identified --
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| 11 MR. MICHELSON: By looking at, what do you mean? Do 12 you mean you actually went in and postulated such breaks and 13 followed where the water and the steam went and so forth?
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| 14 MR. SHU: No. Let me repeat again. We are not able 15 to follow the sequence through to core damage. What we did 16 was we looked at the system identified, we approximated the 17 length of pipe and the rupture frequencies due to that pipe 18 and whatever maintenance -- you know, because heat exchanger 19 has to be maintained. It fails, and based on some rough 20 number on maintenance frequencies and failure to maintain the 21 integrity of the isolation valves and leading to a 22 flood-initiating frequency.
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| 7 23 Beyond that --
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| 24 MR. MICHELSON: Let me ask the question differently, 25 then. In the process of doing your examinations, you only
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| (
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| 153 1 applied tho singlo-feiluro critorion. You didn't question, 2 for instance, whether the isolation valves would close but 7- .
| |
| k 3 rather assume one of them might not but certainly not both?
| |
| 4 Is that the approach you used in doing this flooding study or 5 did you assume the valves didn't close?
| |
| 6 MR. SHU: I don't think I'm making myself clear. We 7 did not go and follow the scenarios beyond the initiating 8 event. So once we postulated a rupture, I did not go back to 9 even ask whether the valves would work or not.
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| 10 MR. MICHELSON: You said something about it didn't
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| : 11 lead to core melt, so I wondered what basis you used in making 12 that decision. I thought you said it didn't lead to core melt 13 and that's why you didn't go further, but maybe I 14 misunderstood you.
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| 15 MR. EBERSOLE: How could you do a flooding study if 16 you did or did not specify the valve closed or didn't close?
| |
| 17 MR. SHU: We didn't do a flooding study. We only 18 spent four weeks' time doing a brief review of what G.E.has 19 done, and our review entails some reevaluation, reassessment 20 of the flood-initiating frequency. That.means how likely was 21 the frequency, likelihood of a particular type of flooding to i
| |
| 22 occur. After the onset of a flood what would happen, we did 23 not have the time and the resources to go into.
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| 24 MR. MICHELSON: I'm going to withdraw my question.
| |
| i 25 Thank you.
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| {~')
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| v l
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| 154 1 MR. OKRENT: Okay. Since wo havo only about, at 2 most, an hour and 15 minutes left, if we go 15 minutes 7s 3 overtime, I think that's all the Chairman will give me. We 4 had better move along because we are going to need Item 12, 5 There are some things other. Could G.E. summarise in five 6 minutes instead of ten?
| |
| 7 Could you summarize how you propose to approach it?
| |
| 8 The committee will hear more about it in a different sense 9 temorrow.
| |
| 10 MR. HOLTZCLAW: Kevin Holtzclaw from General 11 Electric. I should start out by -- in light of what you heard 12 in one of the subcommittee meetings yesterday and what you 13 will be hearing tomorrow -- with the statement that we did not 14 have a detailed operational procedure for containment venting 15 for GESSAR. That would be part of the plant operational 16 procedure guidelines, or operating procedures rather, for the 17 specific plant.
| |
| 18 However, as required by the emergency procedure 19 guidelines, we would surely intend to have that capability, or 20 have the vent capability in GESSAR, and such things as the 21 selection of some of the detailed parameters for containment 22 venting which would be part of the detailed procedure have not 23 as yet been determined for GESSAR like vent pressure criteria 24 and some of those specific parameters.
| |
| 25 We can now tell you what we believe some of those
| |
| | |
| 155 1 parcmotore dopond on and how vont pressuro would bo dofinod as 2 well as the appropriate vent pathways.
| |
| 3 The venting pressure depends a good deal on the 4 pathway chosen as far as having the operability of components 5 along that pathway to ensure that they can stand any pressures 6 that might be induced; things such as the SRV air system 7 pressure, the valve-operated pressures along the pathway or 8 capabilities, the limitations that might be imposed on 9 containment pressure indication itself. So that the operator 10 -- we would propose a pressure that the operator would have 11 some reasonable capability of knowing what that containment 12 pressure was during that sequence.
| |
| 13 And then finally, the ultimate containment pressure 14 capability itself would be another parameter, another item 15 that the choice of a vent pressure criteria would depend on.
| |
| 16 In looking at the, GESSAR design, there are two 17 methods of venting that we have considered would be f 18 appropriate pathways. One would be through the normal l
| |
| 19 containment purge system which is a seismic Class 1. The 20 other is a specific vent line as part of the UPPS system.
| |
| 21 I'm sorry. That's not necessarily a dedicated line just to l
| |
| i 22 UPPS but it is a line that is specifically associated with the 23 UPPS system.
| |
| 24 Some of the objectives --
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| [ 25 MR. WARD: Wait. I didn't quite understand that.
| |
| | |
| 156 1 It's not dodientod? You mean the UPPS would operato the 2 existing vent line?
| |
| O 3 MR. HOLTZCLAW: The existing line. And we're t
| |
| 4 thinking specifically of a line that was identified as a 5 result of CPML rule requirements that called for a dedicated 6 line in the event that containment venting was believed to be 7 an appropriate action. The CPML rule required such a 8 capability.
| |
| 9 Some of the objectives that we have thought of in 10 terms of choosing vent criteria and ve nt pathways is a desire I b 11 to vent from the wetwell as opposed to the drywell in the l
| |
| 12 multi-compartmented containment design, which would maximize 13 the capability of the suppression pool to trap fission i O 14 products in the event of radionuclide release.
| |
| 6 15 Sizing of the line is another concern, or lines; f I
| |
| 16 looking at what lines are available with the intent of being i
| |
| 17 able to vent from minimum-sized lines as a first order of l
| |
| 18 priority, and then looking at exactly when in specific !
| |
| 4 >
| |
| 19 sequences venting would be initiated.
| |
| 20 That's some of the thoughts in our minds as far as !
| |
| L l 21 engineering such a system and as identifying appropriate
| |
| 'i 22 procedures.
| |
| 23 I know one point that is also not on the list that I j l
| |
| 24 just went through would be to carefully choose a pathway so 25 that you don't necessarily exacerbate an accident condition l
| |
| l ;
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| i I ,
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| e
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| | |
| 157 1 that caused you to vent in the first place. And looking at 2 things like the line integrity, for instance, and assuring 3 that you might not necessarily be going through a line of 4 hardened pipe and come up on ductwork that might be adversely 5 affected by high pressures, which could have an implication on 6 the environment outside of that ductwork, given the potential 7 for losing that integrity.
| |
| 8 MR. EBERSOLE: What sort of discipline is there at 9 the present time required of the owner / operator if he proposes 10 to do something --
| |
| 11 MR. OKRENT: Jesse, I wonder if we could sort of cut 12 short the discussion on this topic today. It's going to be 13 discussed tomorrow. It's one of the --
| |
| 14 MR. EBERSOLE: I wanted the generic process, though, 15 in case we liberate this process to the utilities as has been 16 proposed.
| |
| 17 MR. OKRENT: The Staff has liberated it. We'll have 18 to backfit if we're going to do anything. But if you're 19 agreeable --
| |
| 20 MR. EBERSOLE: Sure. I will bide my time. How's 21 that?
| |
| 22 MR. OKRENT: I'm trying to save you and G1r ne time in f
| |
| 23 the end, among others. Unless there are burning cuestions on 24 this, I would suggest we go on to number 10, which is shown as 25 GE,-but perhaps the Staff also has comments here. In other f
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| n , - -- - - , , , - - - - . . . - , -
| |
| | |
| 158 1 words, what is the curront status of UPPS. And then, as you g 2 see there, questions have been raised -- will UPPS work in the
| |
| -s 3 event of a fire? This could depend on the size of the fire.
| |
| 4 And members have raised questions about should it be a more 5 encompassing system, a better system, and so forth.
| |
| 6 I don't know whether the Applicant or the Staff has 7 any comments in that area or not. But anyway, could we assess 8 the status of UPPS first as GE sees it and then as the Staff 9 sees it, then we'll see what questions the committee has.
| |
| 10 MR. VILLA: Do you want me to begin?
| |
| 11 MR. OKRENT: Why don't you?
| |
| 12 MR. VILLA: The current status of UPPS is I think 13 something that you would call conceptual because we have not h i 14 created design details of the system. However, we have 15 defined the functions of the system to be, one, to 16 depressurize, to vent the containment and provide mskeup water 17 to the core. And I think in brevity, that is the status of 18 the system.
| |
| 19 Some questions about expanding its capability. ;
| |
| 20 Yesterday it was asked if UPPS could be operated during a i
| |
| , 21- fire, and since it it s e s the fire water, so to speak, for t l
| |
| 22 water. The answer to that question is yes. The. water supply j 23 has the capability to deliver the maximum fire demand of water :
| |
| 24 to any compartment and still operate the UPPS system. But t 25 that only relates to probably one fire, and depending, if it's i I
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| f n
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| | |
| 159 1 not the maximum domand like a largo area in the roactor s 2 building. Then if it's a place of small demand, there may be
| |
| ''' 3 two or three local fires or fires that are in compartments.
| |
| 4 That's all I was going to say unless you have further 5 questions.
| |
| 6 MR. OKRENT: Let's see what the Staff's view is.
| |
| 7 MR, SCALETTI: The Staff's view is somewhat 8 similar. It is a conceptual design; the final design will 9 have to be provided later, The functions have been identified 10 and we will have to meet those functions to be able to carry 11 out those functions later on.
| |
| 12 We have also identified that it probably should be 13 somewhat seismically hardened. Certain precautions taken when 14 the system is installed to ensure that you don't end up 15 putting air bottles in a non-Category 1 buildidD, subjecting 16 them to an incapability to respond to these functions or to 17 carry out these functions if you have an earthquake or seismic 18 event.
| |
| 19 So the details of the system are not provided yet; 20 they will come in later.
| |
| 21 MR. OXRENT: Okay. If I can offer one or two i
| |
| 22 comments. When BNL reviewed PRA, they tried to estimate the t 23 impact of UPPS on different sequences, and they found they had [
| |
| 24 insufficient information to do, let's say, a review up to the [
| |
| t 25 usual standards. They had to make assumptions and make P
| |
| r e
| |
| l i
| |
| | |
| 160 1 ostimatos. I think that's a fair paraphraso of what they 2 said.
| |
| O 3 And the Staff, just in telling us that they hardened 4 seismically somewhat -- I don't know what that means; the
| |
| )
| |
| 5 Staff said in the final plan there would have to be an UPPS l 6 that met some kind of criteria. But at the moment, I would 7 say it's a little hard for me to know how, then, one will 8 judge what it was that's being agreed to now. That's one 9 person's view of -- well, the element of elusiveness, if you 10 want to put it, with regard to just what is UPPS.
| |
| 11 Now, I don't know whether the committee has 12 questions on what we have heard or if they want to raise 13 questions along additional lines on UPPS.
| |
| 14 MR. REMICK: I have a question. When would the UPPS 15 design be reviewed? Would this be as part of an amendment to 16 FDA or would this be at the, CP stage of each unit?
| |
| 17 MR. SCALETTI: It could be either. It's a GE 18 system. It would be incumbent on them to provide whatever 19 design UPPS has provided. It could be an amendment. Well, it 20 may not require an amendment. Well, it may require an 21 amendment to GESSAR, but it would be either GE or it could be 22 tho utility / applicant including at in their application which 23 references GESSAn in the final design review. It would take l .
| |
| l 24 place then.
| |
| 25 MR. REMICK: Has GE made any decision?
| |
| (
| |
| | |
| 161 1 MR. SHERWOOD: Yes, sir. It's our intent now to x 2 provide this design at the CP stage when we have an applicant.
| |
| 3 MR. OKRENT: Other questions?
| |
| 4 MR. WARD: I guess I don't quite understand then, 5 the FDA is approved without any commitment to UPPS?
| |
| 6 MR. SHERWOOD: We have made the commitment to UPPS, 7 including -- as was stated by the Staff -- we call it a 8 hardened version. If that's the right way to describe it. So 9 we have committed to that. It's our desire to wait until we 10 actually have a customer who is interested in the system as to 11 where we go to the additional substantial expense of providing l
| |
| 12 the detailed design.
| |
| 13 I guess if I may -- could I take a second and make a 14 couple of remarks?
| |
| 15 MR. OKRENT: Sure. $
| |
| 16 MR. SHERWOOD: In terms of things that are working ,
| |
| 17 with UPPS, I think we believe that with the PWR 6, the safety 18 of the plant is substantial in the sense of the PRA work that 19 we did as well as the confirming work by BNL. So therefore, ,
| |
| 20 we believe -- and I think the Staff concurs -- that Phe PWR 6 21 MARK III meets all the regulations as they now exist" without l I
| |
| 22 UPPS. And indeed, that may be the safest plant offered in the
| |
| . t 23 United States at this stage of the game.
| |
| 24 But beyond that, we have decided to offer the UPPS ll 25 system as part of the severe accident effort and the severe ,
| |
| l l
| |
| I i,
| |
| w - -- - ~ e --a - - , - - , - -
| |
| -m , - n ~- w
| |
| | |
| l 162 1 accident result as a way to even reduce the core damage 2 frequency. However, in light of the realities of the 3 situation in terms of future applicants for this plant, we 4 would propose not to go into the detailed design at this stage 5 of the game until we are assured that there would be an 6 applicant and a customer.
| |
| 7 But we have indeed committed to the Staff to provide 8 that design when that indeed happens.
| |
| 9 If I could just take another second, a similar case 10 exists with the hardened igniters for hydrogen control It 11 would be very straightforward for us to provide a design, for 12 example, which would be an offshoot of one of our utility 13 designs. But again, there is 'he hydrogen control owners m
| |
| 14 group which is still going on and so forth. So our preferred 15 mode is to wait until those results are done and then design 16 it once, not design it twice.
| |
| 17 MR. OKRENT: Are there any other questions at this 18 time on UPPS and its status?
| |
| I 19 MR. REMICK: Dave, I'm not sure I understand yet 20 what hardened means in this sense.
| |
| 21 MR. OKRENT: Why don't you ask them to explain it to l 22 you. I r
| |
| 23 MR. REMICK: ~You said something about bottles. That ,
| |
| i 24 I think I can understand, but what else do you have in mind 25 when you talk about a hardened UPPS?
| |
| i
| |
| | |
| 163 1 MR. SCALETTI: The bottlos, the anchorago of the s 2 bottles. We haven't gone into -- maybe Calvin Shu or 3 Rosenthal might have some comments associated with that.
| |
| 4 MR. ROSENTHAL: Rather than requiring that the 5 system be 1E or qualified to a certain level of seismic 6 acceleration, we thought it proper for this sort of system, 7 which is surely beyond design basis events, to take the system 8 and look at it when it is designed on a component basis; look 9 at what contributes to fragility of the system, what are the 10 weakest components; make a decision if some of those 11 components should be hardened or not and work our way up in 12 terms of seismic accelerations on a case by case, component by 13 component level rather than requiring some broad-scale 14 qualification which didn't take into account the judgments of, 15 let's say, the people who typically look at fragilities and i
| |
| 16 could say okay, that device is fine the way it is; this other 17 thnig needs something.
| |
| 18 MR. REMICK: So this is in the same way as you're 19 talking about the igniter systems; you had some high 20 confidence it would work.
| |
| 21 MR. ROSENTHAL: Yes, sir. Ilu t given our QA program, 22 I just don't see for these beyond design basis events, clearly 23 severe accident events, that we have to apply the same 24 standards of testing and paper trail I think there is some
| |
| ) 25 room for judgment and prudence. Let'the fragility experts
| |
| | |
| 164 1 look at the device and ooo what can be pragmatically dono.
| |
| 2- MR. REMICK: Any preconceived ideas that this would Os 3 be to .6g, twice the SSE? That that would be your criteria in 4 looking at-it, in the case of the ignitors?
| |
| 5 MR. ROSENTHAL: The preconceived notion is that it 6 should be relatively easy to have confidence that that 1
| |
| 7 equipment would survive because its diesel glow plugs --
| |
| 8 MR. REMICK: I'm not arguing that case. I'm sorry I 9 wasn't clear. In the case of UPPS, is the Staff willing to 10 look for a hardened system that would withstand twice the SSE, s
| |
| 11 as apparently was the case --
| |
| 12 MR. RUBIN: We have not established a hardened f 13 criteria for the resistance of the system. What we have done i
| |
| 14 is required that the soft spots of the system be identified in 4 15 a rigorous manner by the applicant, by GE, when the system is 16 designed, and give us an opportunity at that point to make a 1
| |
| 17 decision how hard it should be.
| |
| I 18 In the course of the BNL review, the likely soft
| |
| ! 19 spots have been identified, but we have to admit that we are l
| |
| i 20 shooting pretty much in the dark. It looks right now to be 21 such areas as the water supply, the air bottles, the primary i
| |
| 22 functions of the UPPS system. We certainly would expect those 23 to be looked at very carefully.
| |
| 24 MR. EBERSOLE: Mr. Chairman, I had an interest in 25 the earthquake regime, when we can get back down to earth with
| |
| | |
| . . ~ . -. . - - ._. _. -
| |
| 165 1 more realistic things liko firos. We have an oxpensivo 2 concept in design which we have told the plants over the years 3 to provide remote shutdown rooms to account primarily for 4 control room fires and other fires and focus on points where 5 we have the control ability of common, redundant systems.
| |
| 6 This system here would provide capability to cope 7 with a fire anywhere if we pay a little attention to it. Yet, 8 I find it somewhat amusing, cynically perhaps, that we only 9 look at the seismic aspect.
| |
| 10 That would be my complaint about it, the narrow 11 scope competence of the UPPS concept.
| |
| 12 MR. OKRENT: Jesse, my guess as to why, in the last 13 month or two, the Staff has proposed the seismic hardening it 14 that according to their estimates of the PRA, seismic is an i 15 important contributor and if UPPS has no seismic capability, l 16 they can't use it. So they,are trying to, I think, get it 17 useful in that series of sequences.
| |
| l 18 And if I can respond in a way to what Forrest was 19 asking, I think when they're talking about a .6g, it's not a 20 .6g SSE design basis with all of the code margins and so I
| |
| l l 21 forth; it's that you have -- well, perhaps I will put words in 22 their mouths -- a fairly high confidence that it will function 23 at .6g, and that means you h .2 v e used up, you know, some of the ;
| |
| 24 margins that are in the typical analysis. ,
| |
| 25 MR. REMICK: I understand that. At times, I can i
| |
| ,, -- - , - 4..
| |
| | |
| . .. - .. . = .
| |
| , 166 1 ovon oppinud it. But then I got worried from a regulatory, rw 2 legal standpoint, is the Staff trying to require things twice b 3 SSE? I don't know what the regulatory basis is. I think it's 4 great prudency, and I don't have a problem with it, but I do 5 have that legal, regulatory concern. Is it a ratchet underway 6 that we will hear about?
| |
| 7 MR. LXRENT: If you look at what is evolving as the 8 opinion of -- I'll use the word, quote, " experts" who review 9 the seismic capability in plants, they are estimating a very 10 wide range in the fragility or capacity -- take your choice --
| |
| 11 of components and structures and so forth, all of which are i 12 nominally capable of meeting a certain SSE, ranging from some 13 that will take only perhaps three times the SSE to some that s
| |
| 14 will take twenty, okay, because there are other constraints on
| |
| ; 15 design or whatever.
| |
| 16 And if you are trying to increase the capability of 17 the plant that exists to earthquakes, I think they will not 18 recommend a uniform increase in capability across everything, 19 because thic would be very inefficient and unnecessary. So 20 now the question is, what do you do?
| |
| i 21 MR. EBERSOLE: I hope you didn't mean I was saying ,
| |
| i 22 that we didn't need -- I would agree to sacrificing the 23 current fire protection system in its entirety, if we put a ,
| |
| i 24 properly competent UPPS system in place to cope with it. ,
| |
| 25 MR. OKRENT: If you were the plant owner, would you?
| |
| f
| |
| | |
| 167 1 MR. EBERSOLE: Yes, sir. But I would have a good 7s 2 UPPS system.
| |
| n, 3 MR. OKRENT: The frequency of fires in plants is 4 high enough.
| |
| 5 MR. EBERSOLE: I'm talking about nuclear safety, not 6 the commercial aspect.
| |
| 7 MR. OKRENT: Any other comments on the UPPS system 4
| |
| 8 at this time, because I do want to get through this.
| |
| 9 [No response.)
| |
| 10 MR. OKRENT: The next item -- let's see if I can 11 reconstruct what it is, so we can cover it -- systems 12 interactions which could arise again during an earthquake by 3 13 failure of non-seismically qualified systems impacting on 14 seismic, such as the Diablo Canyon study, and in fact, which 15 studies are one of the principal -- five or six principal 16 recommendations of this expert seismic panel that the Staff i'
| |
| 17 has. These are currently not part of the proposed Staff i 18 requirements for GESSAR, unless there's been a change since
| |
| . 19 yesterday. And with regard to fires and their possibility of 20 them being close by an earthquake, that seems to be a 4 1 21 relatively unstudied question.
| |
| 22 So we are calling the attention of the committee to 23 this, and now let the Staff or GE offer any comments that they 24 would like to on either of those two subjects.
| |
| 25 MR. VILLA: Do I understand correctly that we are
| |
| )
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| | |
| 168 1 discussion the issuos yostorday about firo, the performanco of 2 the fire protection system after an earthquake or deleterious 3 effects that can be caused by the failure of the fire 4 protection system?
| |
| 5 MR. OXRENT: Well, in fact, you have pointed out -
| |
| 6 that the list --
| |
| 7 MR. VILLA: It's not long enough. -
| |
| 8 MR. OKRENT: -- that I have shown here is too short 9 a list, and you have identified one or two things that we 10 talked about yesterday with no resolution.
| |
| 11 MR. VILLA: Thank you.
| |
| 12 What I have done in response to those two questions I 13 is, check back with our designer, and I found a couple of 14 things that we didn't know yesterday, and one of them is that 15 the fire protection system throughout the plant is seismic, 16 and it is designed, including the sprinkler heads, to survive 17 an earthquake equivalent to the design basis for the entire 18 plant. It is not designed to function -- in other words, it's 19 not a safety-grade function; it's a safety-grade design, so 20 that components will not fall all over the plant, as we 2
| |
| 21 discussed yesterday.
| |
| 22 MR. MICHELSON: Does that include actuation, seismic 23 actuation?
| |
| 24 MR. VILLA: In terms of design, it doesn't exclude 25 actuation; however, the experience is --
| |
| )
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| l
| |
| | |
| 169 ;
| |
| 1 1 MR. MICHELSON: That was our probicm yesterday.
| |
| 2 MS. HANKINS: Actuation of the sprinkler system is 3 through thermal links.
| |
| 4 MR. MICHELSON: In all cases?
| |
| 5 MS. HANKINS: For all the deluging systems, for all 6 the sprinklers. Those sprinkler heads that have the links on 7 them are qualified to .3 SSE, so you would not expect 8 actuation.
| |
| 9 MR. MICHELSON: What you really have to say is that 10 all the water systems in the plant are of that type. Then 11 it's a good statement. But you haven't told me that all the
| |
| , 12 water fire control systems are of the admission type with i
| |
| 13 therma.. links at the nozzles, so that you have redundant O 14 control over actuation.
| |
| 15 If it's true, that's great.
| |
| 16 MS. HANKINS: It's true of the sprinkler heads. The 17 manual hose systems -- there are no sprinklers in the ECCS.
| |
| 18 MR. MICHELSON: There are no deluge systems in these 19 plants.
| |
| 20 MS. HANKINS: In the ECCS rooms.
| |
| 21 MR. MICHELSON: How about other areas of the plant l 22 where there is vulnerable equipment, instruments, motor I
| |
| I 23 control systems, whatever? You know, it's an equally good way 24 to get ECCS function.
| |
| 25 MS. HANKINS: There are no sprinkler systems in the i
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| k 1
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| | |
| 170 1 oloctrical rooms either.
| |
| 2 MR. MICHELSON: None at all.
| |
| 3 MS. HANKINS: That's true.
| |
| 4 MR. MICHELSON: There is no way water can get into 5 the electrical rooms from sprinkler systems that actuate, say, 6 above the electrical rooms, because they are all of the type 7 wherein it takes two failures before they would actuate.
| |
| 8 MR. VILLA: That's correct.
| |
| l 9 MR. MICHELSON: Those are good words. If you put i
| |
| 1 10 them all together and tell it right, I would n
| |
| 'e happy as could 11 be.
| |
| I 12 MR. SHEWMON: Let me ask a question for 13 wl=rification.
| |
| i 14 When you say .3 SSE, you mean an SSE of .3, or .3 [
| |
| 15 times the SSE?
| |
| 16 MS. HANKINS: An SSE of .3g.
| |
| 1 17 MR. EBERSOLE: Do you have some exclusion 18 requirements preventing massive and uncontrolled discharge of 19 CO2 into critical safety rooms, thereby blowing them up or i
| |
| ; 20 otherwise disrupting the proper performance of systems inside, l
| |
| ?
| |
| 21 due to the fact that these control devices from tank farms is ;
| |
| : l 22 not qualified?
| |
| 23 We just heard Hope Creek this morning where they i l
| |
| 24 threw out twelve tons. ;
| |
| 25 MR. VILLA: We don't have someone here to answer the i
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| I i
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| | |
| 171 1 question.
| |
| 2 MR. EBERSOLE: You can do it by venting or QAing the O 3 control devices or whatever.
| |
| t 4 MR. MICHELSON! The interface requirements by [
| |
| 5 whatever the utility supplies in terms of fire protection, are ;
| |
| i 6 they going to have to meet the same requirements that you 7 stated? I I
| |
| 8 MR. VILLA: Certainly.
| |
| 9 MR. MICHELSON: So you have prescribed interface i i
| |
| 10 requirements on fire protection that, in essence, say there [
| |
| 11 will be no deluge systems, for instance. f I
| |
| 12 MR. VIL'LA: We designed the entire system. [
| |
| 13 MR. MICHELSON: Outside balance-of-plant? f I
| |
| ''} 14 MR. VILLA: The only balance-of-plant that exists is s_j j t
| |
| 15 in the turbine -- I i
| |
| ?
| |
| 16 MR. MICHELSON: Right. How is it prescribed? [
| |
| 17 MR. VILLA: It isn't. f 18 MR. MICHELSON: You are sure, though, there is no t
| |
| b 19 way there are interactions between inadvertent actuations l l 20 there and flooding above the compartments or whatever? That's l +
| |
| l 21 somehow an interface requirement? !
| |
| I t l 22 MR. VILLA: It's a design requirement. In our part I
| |
| 23 of the building, the rooms are tight.
| |
| 24 MR. MICHELSON: You put a barrier up against it?
| |
| 25 MR. VILLA: And compartmentalized it.
| |
| t i
| |
| i
| |
| - -. - - , - - - _ . , , - . - . - - - . . , - - - - - , - . a . , . , , ,
| |
| | |
| t 172 1 MR. MICHELSON: Thank you.
| |
| ,_ 2 MR. OKRENT: Does the Staff have any comments in
| |
| (
| |
| 3 this area?
| |
| 4 MR. SCALETTI: No, the Stsff has none.
| |
| 5 MR. VILLA: Could I make an additional comment? I 6 hope it doesn't drag things on further, 7 The other question that came along on this subject 8 was the interface requirements for non-seismic equipment, and 9 I have confirmed that we do establish interface requirements 10 for non-seismic equipment. In fact, in the nuclear island, we 11 designed the systems and analyse the systems or the ,
| |
| 12 non-seismic components, so that they cannot cause significant 13 consequential effects on the emergency or safety-related ;
| |
| 14 equipment.
| |
| 15 MR. OKRENT: This is a GESSAR II requirement?
| |
| 16 MR. VILLA: Yes, j
| |
| 17 MR. OKRENT: Is there someplace in the document l 18 where you define it?
| |
| i 19 MR. VILLA: In the document structure, yes, but I f 20 will have to find it for you. ;
| |
| 21 MR. OKRENT: Would you let us know, because Staff ;
| |
| r i
| |
| 22 does not have that on its own, as far as I know. i 23 MR. MICHELSON: You recall the reason we're asking ;
| |
| 24 the question. How many non-seismic failures occur during an 25 earthquake? I'd expect in this document to find out what the [
| |
| t
| |
| | |
| 173 1 analysis assumptions should bo.
| |
| 2 MR. VILLA: Okay.
| |
| '" Any other discussion on Item 11 at this 3 MR. OKRENT:
| |
| 4 time?
| |
| 5 CNo response.]
| |
| 6 MR. OKRENT: Let me come back to Item 3. I think 7 Mr. Michelson has had a chance -- I have not -- to scan the 8 document that Mr. Scaletti gave us.
| |
| 9 This is the document, isn't it, Mr. Scaletti 10 (indicating)? Does it look about the right thickness?
| |
| i 11 MR. SCALETTI: About the right thickness.
| |
| 12 MR. MICHELSON: I don't recall receiving this during I
| |
| 13 the subcommittee meeting. Isn't that what you said?
| |
| 14 MR. SCALETTI- No, no. That is the proposed General ;
| |
| 15 Electric amendment to GESSAR, covering the severe. accident i
| |
| I 16 interface requirements. ,
| |
| i 17 MR. MICHELSON: I thought from the chitchat earlier, I 1 :
| |
| 18 this was to be a list of the interface documents, but I l
| |
| 1 19 guess it's another list that we didn't get, ,
| |
| i E
| |
| 20 MR. SCALETTI: The section of that document which is I :
| |
| l i
| |
| 21 Table 1.9 will be amended for GESSAR II. -
| |
| 22 MR. MICHELSON: It doesn't list the interface 23 documents, though? '
| |
| 24 MR. SCALETTI: No. l 25 MR. MICHELSON: I thought somehow we were finally :
| |
| i I
| |
| l r, , . _ - . - _ _ _ - . - .-
| |
| | |
| 174 l
| |
| 1 getting that list of intorface documents. I kuoss that will s 2 have to be some other time.
| |
| 3 MR. OXRENT: Where in this is one to find your 4 quantitative requirements on balance-of-plant? Why don't you 5 look at this while we go ahead?
| |
| 6 [ Document handed to Mr. Villa.3 7 MR. OKRENT: Mr. Reed indicated he had a point he 8 wanted to raise.
| |
| 9 MR. REED: I expect what we're working toward here 10 is perhaps a letter from the ACRS, and we try for consensus 11 letters, and we don't'like to have additional comments. And I
| |
| { 12 am worried about past history with respect to something I did 13 30-some years ago.
| |
| l O 14 Some 31 or '2 years ago, I took the position to a I 15 number of utilities that the boiling water reactor concept 16 perhaps would have metallurgically and corrosion-wise many 17 problems because of the oxygen produced in the recirculating 18 fluid.
| |
| 19 Now I have listened over the last 30 years to 20 numerous advances or steps backward with respect to the oxygen 21 issue and to the cracking, p . pe cracking issue. And here we 22 are f r.c e d 30 years later -- I am faced 30 years later with 23 again perhaps taking a position, as I did with those 24 utilities, on whether or not I feel that the BWR and the 25 advanced GESSAR unit.has overcome its environmental 1
| |
| | |
| 175 1 metallurgioci problom.
| |
| 2 Now from what I heard this morning, it didn't sound U-~ 3 very much like it had, except for one last hope, perhaps, and 4 that is that hydrogen might be used as an inhibitor to try to ,
| |
| 5 overcome the problem. It sounds to me, from what I heard this 6 morning, that the welding -- the heat treatment of the welds 7 and even the materials that have been placed into use are not 8 necessarily the solution.
| |
| 9 Okay. So I have a dilemma. And I would like to 10 know what assurance the Staff can give me that this hope of 11 hydrogen will, in fact -- and GE can give me -- that this 12 issue of pipe cracking, which I think is a serious safety 13 issue, is, in fact, going to be solved, is solved, and what s
| |
| 14 proof do we have that it is?
| |
| 15 MR. SHERWOOD: All the people who told us so, told 16 us they told us so thirty years ago. I didn't notice your 17 name on the list.
| |
| 18 MR. REED: Let me say, that report was a 19 confidential report to eleven utility companies written by me, 20 following work on the borax reactor. .
| |
| 21 MR. SHERWOOD: We, around 19 -- or the end of 1969 22 or '70, when the pipe crack problem appeared, GE started a i
| |
| 23 fairly substantial study program, and then in the early '70s, 24 we augmented that by a major test program in-house, which, I 25 think many of you have seen the GE' pipe test facilities where
| |
| | |
| 176 l 1
| |
| l 1 wo not up semothing liko 30 to 50 cells for tosting various 1
| |
| 2 types of pipe to, number one, understand the phenomenon and, l g'%g .
| |
| O 3 number two, try to solve it. And that testing program 4 continued over something like five to eight years.
| |
| 5 And as a result of that, it was determined what kind 6 of steels were more susceptible than others to intergranular 7 stress corrosion cracking. And out of that program came the 8 recommendation that the BWRs go to 316 nuclear-grade stainless t
| |
| 9 steel. That recommendation was discussed with the Commission 10 and with the Spence / Bush committee and a number of other 11 committees and so forth, and I think now is sort of, you know, t
| |
| 12 informally accepted in the BWR community. j 13 Later, a number of BWRs began'to actually change out 14 some of this piping to this 316 nuclear-grade stainless steel 15 as best they could, while others used other mitigations, such 16 as various types of heat treatment and so forth.
| |
| 17 So we feel -- and I think people like the 18 Spence / Bush group and so forth feel like the problem, at least 19 in terms of selecting the right kind of steel, has been 20 corrected as a replacement of the 304 and so forth with 316.
| |
| 21 MR. REED: Are you addressing the weld cracking 22 issue, or are you addressing the piping?
| |
| 23 MR. SHERWOOD: I'm addressing the problem of 24 intergranular stress corrosion cracking, which is the culprit.
| |
| ! [" 25 for the change of a substantial amount of steel right now.
| |
| \
| |
| k
| |
| | |
| 177 b, 1 MR. REED: I guess I will have to ask Dr. Showmon to r 2 help me.
| |
| s 3 Didn't I hear this morning that the materials of the >
| |
| 4 welds were still cracking, and more evidence of more cracking 1
| |
| 5 had been discovered? l 6 MR. SHEWMON: Those were older plants, though, and 7 if ths start with a new plant, they will put the material in 8 that he spoke of, which will be a step in the right 9 direction. They'll follow the PWR Owners Group practices on 10 water chemistry, which would be a big help. They probably 11 would use stress adjustment, as the Japanese have, and the 12 Japanese have largely overcome this problem on their own, and 13 they might then use hydrogen. i 14 It seems to m?, these three steps -- material 15 selection, water chemistry, whatever --
| |
| 16 MR. SHERWOOD: That's correct. And hydrogun.
| |
| 17 MR. SHEWMON: Stress adjustment.
| |
| 18 MR. REED: We are convinced that the material 19 selection is now correct? Because haven't I heard that the 20 different types of I n c o;t a l welds, even the latest version of 21= Inconel weld, has cracked? [
| |
| 22 MR. SHEWMON: There is no car made so well that you o
| |
| , 23 cannot tear it up if you drive it like a teenager. The same ,
| |
| 24 thing with a piece of 18-8 stainless steel. If you put crappy f
| |
| , l
| |
| , 25 enough water and about enough stress on it, it will stress. <
| |
| - f 6
| |
| [
| |
| I i
| |
| | |
| 178 1 MR. REED: The point is, boiling wator roactors 4
| |
| 2 inherently make crappy water by producing oxygen.
| |
| O 3 MR. SHEWMON: Well, maybe, but my point is, they can d
| |
| i 4 put a better material in it, and they are now agreed on water i 5 chemistry procedures which will help, and the industry has f
| |
| t 6 agreed on stress adjustment procedures which will help. And I e
| |
| 7 think, given those three elements, the chances of it standing i
| |
| i 8 up well are very good. $
| |
| E 9 MR. REED: Chances. What proof? I used the word [
| |
| 10 " proof." l I
| |
| 11 MR. SHEWMON: You've got as much proof as a research !
| |
| 12 program in this country and other countries and operating i
| |
| 13 experience will give you.
| |
| 1 14 MR. SHERWOOD: We have, I think, the proof at least 15 in the materials selection -- is tens of thousands of hours in i L
| |
| 16 the test cells, which showed the comparison between the 304 ;
| |
| i 17 and the 316 and so forth in the water environment. ;
| |
| I 18 MR. REED: These have been oxygenated loops, f 19 potentially oxygenated?
| |
| ?
| |
| 20 MR. SHERWOOD: Yes.
| |
| 21 MR. REED: Realistic field conditions?
| |
| t 22 MR. SHERWOOD: Yes. [
| |
| 23 MR. REED: Realistic stresses, and they are weld [
| |
| l I
| |
| 24 coupons?
| |
| 25 MR. SHERWOOD: Yes. In addition, as Dr. Shewmon ,
| |
| I I
| |
| i l
| |
| l i !
| |
| 1
| |
| | |
| 179 1 said, tho industry is also, I think, paying more attention to
| |
| -~ 2 water chemistry than it had in the past, and we are 3.ow 3 talking to our customers, also as Dr. Shewmon said, about 4 adding hydrogen to the recirc system.
| |
| 5 MR. REED: Will hydrogen work on the same basis as 6 it does in PWRs, the overpressures, et cetera? Will it be 7 effective?
| |
| 8 MR. SHERWOOD: We are doing tests in Commonwealth 9 Edison and plan additional tests.
| |
| 10 MR. REED: Are you putting specimens in the 11 Commonwealth Edison loops, let's say, of these materials in a 12 realistic condition?
| |
| 13 MR. SHEWMON: They not only measure the corrosion 14 potential but the G.E. practice is they will have a test 15 specimen there and monitor where the cracks will stop growing 16 when they get the chemistry down.
| |
| 17 MR. REED: These are stress realistic-type 18 specimens?
| |
| i 19 MR. SHEWMON: Yes. I say this from a corrosion 20 conference I was,at earlier in the week where there were 21 people from their research lab or development lab who were 1
| |
| 22 talking about what their practice was, so I speak through G.E.
| |
| 23 MR. MICHELSON: My uneasiness comes from having 24 heard similar kinds of stories a few years back with quite 25 similar levels of optimism that this problem is now solved and
| |
| (
| |
| | |
| 180 .p 1 still gotting. bad oxperionco frca plants built after that
| |
| , 2 date. r 3 MR. SHEWMON: We are probably growing old and 4 experienced.
| |
| i 5 MR. MICHELSON: I'm not trying to throw cold water 6 on it; I'm trying to make sure that it's understood that this f I
| |
| l r
| |
| < 7 is yet to be really finally proof tested by building plants j 8 and seeing how they go. !
| |
| (,
| |
| 9 MR. SHERWOOD: I have hear that same story from my !
| |
| f 10 engineer, but I think this time we have the test results -- ;
| |
| t i 11 MR. MICHELSON: If you are not getting closer, we 12 are all in trouble. !
| |
| 13 MR. KERR: We have a number of BWRs operating in r 14 this country. Is Mr. Reed proposing that we do something
| |
| , 15 about those, or is it just that we don't want to build any 3
| |
| 16 more unless there is an improvement?
| |
| l 1 17 MR. REED: I think we are going on a great new }
| |
| I 18 venture here after 30 years of my stating in the record to j i
| |
| 19 people that the BWR had a basio conceptual problem. Now I i 20 might have to write to those eleven utilities and reverse i 21 myself, saying that the metallurgical and materials and ,
| |
| 1 22 corrosion.and inhibitor situation has solved all this.
| |
| 23 MR. SHEWMON: Glenn, would you write a letter on the i
| |
| l 24 steam generators through PWRs too? ;
| |
| i i
| |
| 25 MR. REED: I wrote the same letter when the i 5
| |
| h I
| |
| | |
| . - . ~_ . . . . ~ - . . . _- - - ..-. - . . . . _ . . . . - -
| |
| 181 i
| |
| ) 1 Uostinghouso people were horo on steam gonorators 25 years 1
| |
| 2 ago.
| |
| 4 3 MR. WARD: Ten of those would probably tell you the 4 boiler is doing all right, 5 MR. REED: I don't think a single one would tell me i-6 that their boilers are doing.all right. They are having great i
| |
| f 7 fun changing our piping.
| |
| i !
| |
| 8 MR. OKRENT': Glenn, I think this is about as much as i
| |
| 9 you are going to get on this. ,
| |
| i 10 MR. REED: Okay. I'm going to take the word of a !
| |
| 11 number of people here that this real conceptual big issue has 12 been solved.
| |
| 13 MR. MICHELSON: Oh, no, nobody said that. I don't
| |
| ; 14 think Dr. Shewmon said that. At least I hope.
| |
| l 6
| |
| 15 MR. SHEWMON: The research people have solved it.
| |
| f 16 Whether the operating people have solved it or not yet remains i
| |
| l 17 to be seen.
| |
| t
| |
| ; 18 MR. REED: Remember, I'm an operator first, an !
| |
| 19 engineer second, and I get pretty tired of tough designs in L l
| |
| 20 Corvairs being peddled to operators who'are supposed to.make 21 them work.
| |
| 22 MR. SHERWOOD: We-also have another solution to the 23 recirculation of cracking system. .That is we are taking out 24 the recirculation pipes.
| |
| 25 MR. OKRENT: That's not in GESSAR II.
| |
| 1
| |
| | |
| l 182 a
| |
| 1 MR. SHERWOOD: No, but that's ossentially the final 2 solution.
| |
| O 3 MR. REED: I have got one last thrust. What the i
| |
| 4 vessels like, the reactor vessel? Keep in mind I have 5 observed boiling water reactor vessels with the interior 6 cladding cracked.
| |
| 7 MR. VILLA: I believe the answer is stainless steel.
| |
| 8 MR. WARD; Is it 304 or 316?
| |
| 9 MR. MICHELSON: I think it's 308.
| |
| 10 MR. OKRENT: If I could proceed to another item, 11 Mr. Ebersole had one or two broad points. We only have about 12 25 minutes left. ,
| |
| 13 MR. EBERSOLE: I am personally convinced, to the 14 point where I would certainly consider writing an appendix to 15 the letter to say that this plant has such enormous potential 16 for improvement in reliability, not because it's not the 17 safest plant that I know, because I think it is. I'm just 18 trying to capitalize on its intrinsic physical characteristics 19 to, I might say, polish it off as the best thing I know how to
| |
| , 20 do, and without incurring too great a cost. >
| |
| r 21 This causes me to converge to really just two 22 regions. I think we should legitimately and seriously and 23 with great care reconsider what we have got in this reactivity .
| |
| I 24 control system with these two hockey sticks tied together with 25 this one-inch equalizing language which has a curious .
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| r i
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| | |
| 183 1 capability to distributo the potential for solidifying the 2 dump volume, which it would not have if they were not so 3 tied, that line being present for the curious reason they want 4 to reach over and get the other set of level switches by 5 flooding them, too.
| |
| 6 That sounds very funny to me, and I have never yet 7 been able to swallow the notion that we should close this 8 unfortunate dump volume to collect the fluid from the rod 9 discharges before we ascertain that the rods are home. So, i
| |
| 10 risking criticism by advancing a few little design 11 propositions here, I think that we should upgrade the 12 reactivity control system to eliminate the single dump volume 13 from configuration, which is now two hockey sticks tied
| |
| , g ) 14 together with a small pipe, and instead provide a relatively 15 large dump line to the suppression pool from each hockey j 16 stick, which are not tied t,ogether except at the suppression 17 pool level, and that we reexamine the logic such that we prove 18 that it would not or would be better to keep these lines over 19 until the rods are sent home.
| |
| 20 In addition to doing this, these lines and the 21 valves pertaining thereto should be protected from easy access 22 to sabotage so that you can always ensure that you are going 23 to get an open flow path from the rods, and let's not hang out 24 this, as you might say, the fuse to the bomb. I think this 25 would entail reexamining individual rod seals and means to
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| | |
| 184 1 procludo or tolorato the revorso flows that might occur at the 2 scram should you have continued leakage. You can always close (O /
| |
| 3 these open lines to the dump volume.
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| l 4 I am doing this to both, in my view, enhance the 5 reliability of the reactivity control system, which has been 6 steadily under criticism for 25 years or longer, and at the 7 same time I think apply a moderate bit of improvement to the 8 question of malpractice or, worse than that, an aspect to 9 defeating the shutdown system, the reactivity control system, 10 which, as I think we all know, if you do it well can lead to 11 spectacular consequences.
| |
| 12 If we do this and then protect the electrical scram 13 network such that tampering or intrusion into the system will s_ 14 virtually always initiate a trip system, I think we have gone 15 in a practical concept about as far as we can to upgrade the 16 system that shuts the reactor down. I am l e f t ', then, with a
| |
| ; 17 system that is going to take care of it after it is shut down.
| |
| 18 Again, in my view -- I will go back to the UPPS 19 system, which I think is a system very much of focused 20 simplicity to be able to manage virtually all of the accident 21 modes except the short-term cooling after LOCA. This would 22 include ability to cope with fires and obviate practically the 23 nuclear safety aspects of the remote shutdown system and all 24 of the expensive patches we put on to protect the system 25 against nuclear consequences of fire.
| |
| ~s
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| | |
| 185 1 I don't want to in any senso of tho word say that wo 2 don't need commercial fire safety protection, but that is not i
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| 3 the costly part. The costly part is the nuclear safety 1 l
| |
| 4 protection against fire and, for that matter, broken pipes and.
| |
| 5 lost ventilation and loss of the intake building and many 6 other things that you can find.
| |
| 7 I think the UPPS system should as a part of this 8 design be defined sharply, certainly after detailed 9 examination, to cope with virtually all of these accident 10 modes except the short-term cooling after LOCA; that it should 11- be located within the containment to the extent possible with 12 an adjunct hardened building on the perimeter of the 13 containment and preferably linked to the containment only with 14 a channel or a vault at whatever it takes to get to the i 15 containment, and if possible, that vault or hardened structure 16 be provided, as I understand some of the Swiss plants are, if 17 you can get it, with a drilled water well source underneath 18 it, which will provide, of course, a protected source of l
| |
| 19 water. That will not always be possible, so the alternative 20 to that is to provide a protected water supply with a fire 21 truck makeup.
| |
| 22 To further sweeten the concept that I will always 23 get depressurization, I would sweeten or use diverse, probably i 24 mechanical or hydraulic manual means to ensure the desired 25 depressurization. I would use manual hydraulic jacks or
| |
| . . _ _ _ _ _ . - _ _ . ~ . _ . _ _ . _ _ , _ _ . . . _ .
| |
| | |
| 186 1 maahanion1 moons or whatovor. ;
| |
| -s 2 I have abhored the present method of hot solenoids V 3 being used to control pilot valves which then use air, which 4 in most cases is in a limited volume, but in this case, 5 fortunately, has an unlimited gas source to cause continued 6 function. Mainly I am after diversification of the 7 depressurization technique.
| |
| 8 That is all I have to say except one other thought 9 that I would pass out. I think we should have a hard look 10 considering the configuration of the plant, in view of the 11 standing notion that we are going to have to deal with a 12 molten core, to look at the apparently not-too-extensive 13 changes that would be required to cause the current dry b
| |
| \ ,/ 14 drywell to be a wet drywell and thus provide the presence of 15 core coolant without any pumping.
| |
| 16 I think this is consistent with the fact that I 17 think we all must agree, irrespective of the core condition, 18 we are going to try to cool it. I don't know of any means in 19 any practical context to say that the core is incandescent, we 20 are not going to cool it. I think we will always have to cool 21 it, and I am suggesting we cool it when it falls.
| |
| 22 Finally, I find in examining the FSAR an extreme 23 sloppiness in the text -- the language, the narratives -- and 24 a general matching up of all the narrative support to the 25 design drawings is needed, including accurate representation i
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| l
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| _ _ _ _ . _ _ - _ . _ _ _ _ _ a ~ _ _ _ ._ . _ .
| |
| | |
| 187 1 of the designs with much bottor definition and constraints in 2 the FSAR which we now have. At this time it is ambiguous and O 3 incorrect in many, many places, and I use the FSAR as at least 4 the beginning point of examining the general concept and then 5 going into higher detail 6 I am done.
| |
| 7 MR. OKRENT: Are there questions or comments for 8 Mr. Ebersole?
| |
| 9 [No response.)
| |
| 1 10 Don't tell me I'm going to finish early.
| |
| 11 [ Laughter.3 i
| |
| 12 MR. SHEWMON: You can declare a five-minute break P
| |
| 13 with the remaining three minutes.
| |
| 14 MR. OKRENT: Are there any other comments anyone 15 wants to make?
| |
| 16 MR. WYLIE: I had a little bit of the same problem 17 Carl had a little bit ago in interfaces. Maybe I missed it.
| |
| 18 and I will just ask the question. I could not find anywhere in 19 the GESSAR a reference to the equipment grounding systems j
| |
| 20 being provided or lightning protection. Is that somewhere and 21 I missed it?
| |
| 22 MR. VILLA: I believe the reason for that is that we 23 supplied the lightning system. The other system, I didn't 24 hear which one --
| |
| 25 MR. WYLIE: I understood if you --
| |
| 1 n-,+ n, -- _, 4 , - - - - , - , , - - - - - -- w..
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| | |
| 188 i MR. VILLA: Wo design it and so naturally you 2 wouldn't see an interface requirement for it.
| |
| ('-
| |
| 3 MR. WYLIE: I'm not talking about interface. You 4 described it somewhere if you were supplying it, wouldn't you?
| |
| 5 MR. VILLA: Right.
| |
| 6 MR. WYLIE: I couldn't find where you described it.
| |
| 7 MR. VILLA: I'm not sure where it is either. What 8 was the other system?
| |
| 9 MR. WYLIE: It is equipment and instrument grounding 4
| |
| 10 systems a n. d an interface.
| |
| 11 MR. VILLA: Those we also design.
| |
| 12 MR. WYLIE: To withstand lightning protection. But 13 I couldn't find where l' o u described that.
| |
| 14 MR. VILLA: I will have to look.
| |
| 15 MR. WYLIE: Does the Staff know?
| |
| j 16 MR. SCTLETTI: We are trying to find out. Someone 17 thought it would be in Section 7.
| |
| 18 MR. WYLIE: It's not there. I looked.
| |
| 19 MR. OKRENT: Let's not, then, if we don't have the 20 answer new, let's not spend 15 minutes trying to find it. We 21 will --
| |
| 22 MR. WYLIE: I will just make one comment. There is 23 a description of how G.E. plans to ground the generator and 24 the power supplies they are supplying, but that does not cover i 25 the equipment grounding and the ground system for the plant.
| |
| i l
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| | |
| 189 1 MR. OKRENT: Thoro are some other things that'they fs 2 are going to supply after today.
| |
| > 1 V 3 Glenn, you had another point?
| |
| 4 MR. REED: In the barrage that I just leveled and 5 the rising to the occasion by many people to support the 6 metallurgical corrosion issue, I did not hear from the Staff, 4
| |
| 7 to which the question was also addressed. Does Staff have a 8 comment?
| |
| 9 MR. SCALETTI: The only comment the Staff has at 10 the moment is that through the course of the review of GESSAR 11 2, we had a problem with materials. G.E. agreed to change all 12 the materials to -- I mean the radioactive vessel material, 13 the pertinent matorial, to austinitic stainless steel required O,
| |
| g_ 14 by our current Reg Guides, and we found that acceptable. It 15 is written up in Sections 5 and 6 of the SER.
| |
| 16 MR. SHEWMON: You don't have the stainless steel 17 pressure vessel.
| |
| 18 MR. SCA(ETTI: No, no. I'm saying materials used 19 were not previously used before the Staff required this.
| |
| 20 MR. REED: Is the hydrogen also in or out?
| |
| 21 MR. SCALETTI; I can't answer that.
| |
| 22 MR. OKRENT: By the way, Glenn, I have heard the 23 optimism about stress corrosion cracking enough times. Even 24 though I didn't write a letter 30 years ago, don't put me on 25 the side of those who reassured you.
| |
| '\.
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| I
| |
| | |
| 100 1 MR. WYLIE: Lot no mako one other ccamont. In 2 Section 8 where the GESSAR references the feeders to the v 3 electric systems and they say this is to be supplied by the 4 Applicant, there is an interface there that has to be worked 5 out because you have got the phasing to consider and other 6 considerations.
| |
| 7 Now, is that something that is a negotiated thing 8 with the applicant and cannot be referenced here? I assume it 9 is. ,
| |
| 10 MR. SCALETTI. Say your question again. I'm sorry.
| |
| 11 MR. WYLIE: Well, the power supplies that are being 12 supplied to the nuclear island from the balance of plant, it 13 just simply says to be supplied by the Applicant. There is no
| |
| , 14 interface requirements placed on it, and that is something 15 that I can see is very difficult to do. You couldn't really 16 do it without knowing how you are going to design the rest of i
| |
| 17 the plant. It's got to be a negotiated thing.
| |
| 18 MR. VILLA: There has to be an interface requirement 19 someplace.
| |
| . 20 MR. WYLIE: As far as the grounding system they will 21 be using on their power supplies and the phasing and this kind 22 of thing, it affects your transfers and the whole bit.
| |
| 23 MR. EBERSOLE: A quick little thing. You know the ,
| |
| 24 story of the Titanic is popular now. I sort of think my l
| |
| 25 little suggestions here are somewhat similar to what it must
| |
| ?
| |
| | |
| l 191 1 hevo boon, the argumont with tho MBAs, about the bulkhoods 2 that didn't go to the deck because you had never hit, , think, s
| |
| 3 more than three compartments at a crack.
| |
| 4 MR. O. RENT: We managed to run a few minutes beyond 5 3:15, Mr. Chairman, but I am going to propose you take back 6 the meeting and call a break.
| |
| 7 MR. WARD: Okay. Let's take a break and return at 8 3:30 for the next item.
| |
| 9 [ Recess.3 10 Our next topic is Item 4 which is a report from the 11 ECCS subcommittee. , will give that.
| |
| 12 At a recent subcommittee meeting on August 27th we 13 covered essentially four topics, and I will just review with 14 you briefly what was covered on three of these. And then on 15 the 4th topic, which is the resolution of unresolved safety 16 issue A-43 and the companion Reg Guide for containment 17 emergency sump performance, we will have a Staff presentation.
| |
| l l 18 The first three topics, what ,'11 be talking about j 19 is really in the nature of status reports, and the last, the 20 A-43 and the Reg Guide, it will be appropriate for the 21 committee to write a letter on the topic if after hearing the
| |
| ! e 22 presentation we believe that's the right thing to do.
| |
| I 23 The first of the three other topics was a review of 24 the status of the resolution of several concerns about
| |
| : 2. h,d,odyn.m,c s cA ,o.d. in M .. ,. ,, .nd ,,, ,o,1,ng w.t.r c:)
| |
| I l
| |
| l 1
| |
| t
| |
| ~ . _ _ _ . _ _ _ , _ ,- - _ . . _ _ . . . _ . . -- - _ .. . . _ _
| |
| | |
| . _m . _ _ _ _ _ _
| |
| 192 1 rocotor containmonts, This is an issuo or a serios of issuos 2 that has been ongoing for several years.
| |
| \g At the present time, there is interaction primarily 3
| |
| 4 between the boiling water reactor owners group for each 5 containment type essentially, and the Staff. At the present 6 time, many of the issues are resolved. Many of the individual 7 small issues are resolved but not yet all of them. Some of ,
| |
| 8 the plant fixes are in place but not yet all of them.
| |
| 9 The subcommittee expressed the desire to the Staff 10 to hear a little bit more in detail about some of the t 11 resolutions and the analysis used to support the resolutions.
| |
| 4 12 And we plan to' provide the Staff with a series of specific
| |
| { 13 questions and have another meeting within the next month or 1
| |
| 14 two months probably to satisfy ourselves that the resolution 15 of these issues is proceeding in a way that we think is 16 acceptable.
| |
| i 17 The second topic was a discussion of Generic Issue 18 61 which concerns the potential for or the failure of a relief 19 valve discharge line in the wetwell above the suppression 20 pool. This is an issue which was identified by our own Jesse 21 Ebersole, and the Staff has proceeded to the point where it
| |
| : i 1
| |
| 22 has classified it as a medium priority generic issue. And 23 this means that they are working on it and will develop a 1
| |
| 24 resolution plan.
| |
| 25 Jesse, do you want to say anything about that?
| |
| P G
| |
| 6 i
| |
| l _ . _ _ , . . _ _ _ , _ __ _, _ _ ,
| |
| | |
| _ . _.. _ m , _ _ _
| |
| 193 1 MR. E3ERSOLE: I think it's well in hand and wo l l
| |
| I 2 don't need to elaborate on it.
| |
| e V 3 MR. WARD: Okay. The third topic was a discussion 4 of the feed and bleed capability at the Davis Besse plant.
| |
| 5 Back about two, er it might even have been three years ago 6 when we had some extended discussions with the Staff on the 7 capability of the various PWR plants in the country to be 8 cooled by the feed and bleed process, they reported to us at 9 that time that the Davis Besse plant was somewhat unique, and 10 that among plants which had relief capability it was the 11 single one which did not have the system valve and pump 12 capacities to actually successfully feed and bleed at maximum 13 decay heat removal rates.
| |
| 14 Since then, the Licensee had claimed that they I
| |
| 15 could, in fact, successfully feed and bleed immediately siter 16 shutdown, and in fact, had, procedures an place to perform the 17 feed and bleed operation.
| |
| ! 18 The Staff has reevaluatest the situation; they have 19 new information o r, the flow capacity of the pilot operated 20 relief valve, and they now agree with the Licensee that there 21 is at Davis Besse the capability to accomplish feed and bleed
| |
| ; 22 cooling of the core.
| |
| 23 Now there are some caveats with that. First of all, 24 as you know, feed and bleed is not a -- the capaht11ty to feed 25 and bleed is not a requirement for domestic plants, and in i
| |
| | |
| 194 1 fact, I think I can say no plants have the ability to food and 2 bleed with all safety grade equipment. In most cases, the 3 feed comes from the high pressure injection pumps which are 4 safety grade, but the bleed comes from operation of the 5 PORV's, which are not entirely safety grade.
| |
| 6 The Davis Besse situation is a little bit different 7 from that in that at normal pressures, the high pressure 8 injection pumps don't have enough discharge head to feed and 9 bleed. And the reason thev can feed and bleed is they have 10 two charging pumps which do have sufficient output and which 11 have just enough capacity with the now-recognized larger 12 relief capacity of PORV to feed and bleed.
| |
| 13 Now, the Licensee told us in the meeting on August 14 27th that while the charging pumps are not safety grade, they 15 are high reliability and rugged and have a lot of good 16 attributes. However, they are not safety grade, and in 17 particular, both pumps are needed and they are subject to a 18 common single failure which could prevent both pumps from 19 operating. So in that sense, the feed and bleed capability is 20 there; possibly it's not there in as reliable a form as it is 21 at many PWR's.
| |
| 22 Mr. Reed?
| |
| 23 MR. REED: I'm not so concerned about the fact that 24 the so-called high pressure safety injection pumps might not 25 deliver maximum pressure because they're probably in the 1500 l
| |
| l
| |
| | |
| 195 1 or 1600 pound rango. That doonn't bother mo bocause in fact, 2 when you do open up bleed, pressures will reduce enough so 1
| |
| 3 that they will inject.
| |
| 4 The thing that bothers me I think is significant --
| |
| j 5 MR. WARD: Of course, the problem there is'you have
| |
| ; 6 to open up bleed before the system heats up,to the point where 7 the saturation pressure temperature is above the pressure B of the discharge from the pumps.
| |
| 9 MR. REED: Well, what's wrong with opening up bleed i
| |
| 10 as a first effort? I mean, that gets the pressure down.
| |
| 11 You're interested in depressurization also in these events.
| |
| 12 MR. WARD: I see nothing wrong with it, but it 13 happens that on June 9th it wasn't done.
| |
| 14 MR. REED: The thing that bothers me and I think 15 what you're leading up to is Davis Besse now -- how good is it 4
| |
| 16 now? The thing that bothers me is there's no redundancy in 17 the bleed valves. There's only a single trait, and with two 18 valves. And therefore, the opportunity for failure to open is i 19 pretty good.
| |
| 20 MR. KERR: Is there a particular reason it should 21 have been done on June whatever?
| |
| 22 MR. WARD: That's sort of another subject. As it 23 turns out in retrospect, the decision not to feed and bleed, i
| |
| 24 at least in the narrow sense, was a correct decision. It 4 .
| |
| 25 wasn't needed.
| |
| 1 i
| |
| l
| |
| | |
| 196 i MR. KERR: I should hopo.
| |
| 2 MR. WARD: They were able to get the feedwater back O 3 on. However, there's some question about -- I mean, the i 4 procedures did call for the operator to begin feed and bleed i
| |
| 5 under the conditions he had, although there's some confusion 6 about his thi'aty to accurately monitor the level in the steam 7 generator which is the key measurement.
| |
| 8 He apparently had perhaps tens of minutes to make .
| |
| t t
| |
| 9 the decision. Whether he knew that at the time was not all i
| |
| 10 that certain. But he didn't make it and he didn't have to l
| |
| 11 make it because the feedwater was returned. l t
| |
| i 12 MR. EBERSOLE: Dave, I would like to call out a j I
| |
| 13 particular and very curious and disturbing aspect of the Davis [
| |
| t 14 Besse designed. There seemed to be an almost willful f 15 determination to avoid the use of electric-powered pump f
| |
| 16 feedwater, whereas most plants have either electrio main ;
| |
| l 17 feedwater pumps or turbine-driven with condensate or f 6
| |
| j
| |
| ~
| |
| 18 condensate booster pumps to get the water up to the suction. !
| |
| 19 This plant went to the trouble of having reduction f 20 gear on the main turbine pump which then ran the speed down, I
| |
| l 21 to run the condensate booster pump to get suction. Thus, it [
| |
| 22 was totally dependent on steam-driven main feedwater pumps l r
| |
| ) I i 23 including the driving pump to get water to the suction, j 24 nominally called a condensate booster pump.
| |
| 25 Off in the distance there was this late coming a'n d w i i
| |
| | |
| 197 1 poorly organisod singlo, non-safety grado but still good but
| |
| _s 2 disconnected, single motor left to get water in the plant,
| |
| \
| |
| 3 other than the turbine pumps. That's almost a willful and 4 determined effort not to have the viability in the feedwater 5 function, which is a critical safety function.
| |
| 6 I think the Staff should look hard at the balance of i
| |
| 7 plant like this as they do in A-17 -- GDC-17 -- for the
| |
| ! 8 electric systems, look at the aspects of non-safety grade 9 equipment in the context of examining the challenge frequency 10 to safety systems.
| |
| 11 MR. BIESS: Jesse, why do you think somebody would 12 be so foolish as to do that?
| |
| ; 13 MR. EBERSOLE: I Jon't have the slightest idea 14 except some stubborn manager who loves steam.
| |
| 15 MR. SIESS: I thought there was a certain amount of 16 encouragement from on high to use steam-driven pumps because 17 electricity wasn't very reliable.
| |
| 18 MR. EBERSOLE: Gosh, that ain't true.
| |
| 19 MR. SIESS: Every plant has steam-driven pumps.
| |
| 20 M". EBERSOLE: The Japanese use motors.
| |
| i 21 MR. BIESS: I'm talking about this country; I wasn't 22 going quite that high.
| |
| j 23 MR. EBERSOLE: Steam pumps look pretty in pictures 24 until you begin to hang the accessories on them.
| |
| 25 MR. REED: I think when we talk about the 1
| |
| | |
| 198 1 1 utilisation of what I call a primary blowdown to removo 2 decay heat, we always use the term " bleed and feed" rather 3 than " feed and bleed." In my opinion, bleeding comes first.
| |
| 4 MR. WARD: Some plants have -- in fact, I think the 5 other B&W plants -- have such high capacity, high pressure 6 injection pumps that discharge pressure of 2500 pounds or 3
| |
| 7 something, that bleed and feed is possible -- I mean, feed and 1
| |
| 8 bleed is possible.
| |
| 9 MR. REED: You said it right; keep it bleed and l
| |
| 10 feed.
| |
| 11 MR. WARD: But I agree, in many cases it has to be 12 the other.
| |
| 13 MR. SIEGS: Do they do it alternately? I sort of 14 had the idea they went on at the same time.
| |
| a 15 MR. WARD: In some cases you have to open up the 1
| |
| 5 16 PORV's and bleed the system pressure down before you can begin 17 injection.
| |
| 1 i 18 MR. SIESS: Once you begin injection you're doing it J'
| |
| s 19 simultaneously?
| |
| i 20 MR. WARD: Then it's steady state processing.
| |
| 21 MR, SIESS: Bleed and feed rather than feed and 22 bleed.
| |
| 23 MR. WARD: I think that's right.
| |
| t 24 Okay, if there's no further discussion on this we'll
| |
| * 25 go ahead to the next topic which is --
| |
| i t
| |
| | |
| l 199 1 MR. GEED: Davo, cno thing. Choro doos ovorything 2 go from here? Davis Besse is shut down I assume. We have 7s l- 3 seen a review. What is the status of the review now?
| |
| 4 MR. WARD: I think we're going to hear more about s
| |
| 5 that later in a meeting. There is another step coming up. I 6 think we'll be participating in that. I'd like to just wait 7 until later in the meeting this week. It's a good point, 8 though.
| |
| j 9 Okay, the next topic which we covered at the 10 subcommittee meeting was a review of the Staff -- the NRR 11 proposed resolution of USIA 43, which includes a revised draft 12 Regulatory Guide 1.A2, and this is related to containment 13 emergency sump performance.
| |
| 14 The subcommittee heard the presentation, and my j 15 interpretation of the position of the subcommittee is that the 16 proposed resolution and the Reg Guide was satisfactory. But 17 it's a fairly important issue and we think that the full 18 committee should hear a report directly from the Staff on it.
| |
| ; 19 So we are br sging that to you now.
| |
| 20 If any of the other subcommittee members would like 21 to comment before Mr. Sirkis begins his report, this is a good 22
| |
| , opportunity.
| |
| 23 MR. KERR: The subcommittee did get to the bottom of 24 the issue?
| |
| 25 MR. WARD: Right, absolutely.
| |
| i
| |
| - - . . < , , - .....m. , , - . . . . . - - - , , _ , ,_m_ . . - - - - . ,. ,_. ,,y_.. _ , _ _ . . , . . .-
| |
| | |
| 200 1 Okay, Mr. Birkis, if you would go chood, plooso.
| |
| 2 MR. SERKIZ: My name is Alex Serkis. I'm with the
| |
| ' Generio Issues Branch, Division of Safety Technology, and the 3
| |
| 4 Task Manager on USI A-43.
| |
| 5 (Slide.)
| |
| 6 Since I reviewed the Regulatory Guide 1.82 in some 7 detail with the subcommittee, the material I have provided ,
| |
| 8 here is handout material, which is my slides also -- which are i
| |
| 9 my slides.
| |
| 10 If you have questions, please stop me at that time.
| |
| 11 1 will dwell principally on where we stand in final L 12 resolution.
| |
| 13 [ Slide.)
| |
| 14 This is a very brief background, technical 15 background summary. We have concluded our technical findings 16 after about two and a half years of research and study, and f 17 these are reported in Staff's NUREG-0897, Revision 18. This ,
| |
| 18 is a technical information document, which is one package of 19 four which will be pubitshed upon resolution of this issue.
| |
| 20 Additions and modifications have been made to receive inputs 21 that were received during the "For Pubite Comment" period, [
| |
| i 22 additional experiments as well as information received in from [
| |
| f 23 the Owings-Corr.ing Fiberglass Company and the Diamond Power [
| |
| l !
| |
| 24 Company, who ran experiments or participated in experiments in f 25 the HPR facility, where the inserted examples of their f i
| |
| , L I
| |
| ___ , _ _ _ . _ . . - _ . _- , . . _ _ _ _ . . _ _ _ _ _ - _ ~ _ _ _ _ - - . . _ _ . _ - _ . - _ _ _ . - . . - .
| |
| | |
| 201 l 1 insulatien to coo what would happon during a blovedown.
| |
| 2 The results of those two findings are included as O 3 the concluding appendices in NUREG-0097.
| |
| 4 The principal finding I would bring to the 5 committee's attention relative to Reg Guide 1.82 is the need 6 to remove the 50 percent screen blockage criteria contain in i
| |
| 7 Section C.7 of the active Guide, and replacement of that with 8 the requirement to assess debris blockage potential on a 9 plant-specific basis as the principal change to the Regulatory 10 Guide.
| |
| 4 11 The ACRS has been provided copies of this, and as I 12 indicated, just indicated, the Guide has been provided to you 13 in comparative form for ease of reference, as well as being 14 sent to the previous respondees who gave us input.
| |
| ; 15 [ Slide.]
| |
| 16 Dwelling very briefly on what revisions were made to 17 the Reg Guide 1.82, we now discuss separately both boiling 18 water reactors and pressurized water reactors. The post-LOCA 19 recirculation capability is generic to both types of j 20 reactors. As ! Just indicated, removal of the 50 percent i
| |
| 21 blockage criterion, and we also h' ave revised the Reg Guide to 22 reflect some' hydraulics findings and removal of the vortex 23 observations that previously had served as the basis to i i
| |
| 24 quantify air jet. In fact, in many cases, this necessitated ;
| |
| ! i l 25 in-plant tests. !
| |
| l l
| |
| | |
| 202 1 Tho Appondix A in the Rog Guido providos
| |
| , 2 conservative guidelines for estimating the potential for air 3 ingestion. The fourth item in the Reg Guide has been revised 4 to require to an assessment of debris and particula'te effects 5 on the pump bearings and seal assemblies. And that particular 6 item, Item 4, is an item that has been brought back to our 7 attention several times by the subcommittee.
| |
| 8 [ Slide.)
| |
| 9 I would like to dwell briefly with you on the status 10 of implementation of the resolution. The Reg Guide has been 11 revised during the course of revising and resolving USI A-43 12 and reflects the technical findings. The implementation is i 13 concurrent with the resolution of A-43.
| |
| 14 What I mean by this is, there will be two regulatory 15 documents, the Regulatory Guide 1.82, Revision 1 and the f
| |
| 16 revision to the Standard Review Plan, Section 6.2.2, which 17 will be called Revision 4, which we will put down on paper and I
| |
| 18 make available to the community, the technical findings and 19 guidelines and criteria.
| |
| 20 Our intent is to have he Reg Guide, Revision 1
| |
| ; 21 become effective six months following the issuance date of the 22 Guide. It would apply to future CP applications and 23 preliminary design approvals that are docketed six months 24 after issuance and applications to final design approvals for 25 standardized plants that have not received approval at six s
| |
| l
| |
| | |
| 203 1 months following issuanoo of the Reg Guido.
| |
| f 2 [ Slide.3 3 As we stand today, I can summarize the current 4 resolution position pretty much this way, t
| |
| 5 A regulatory analysts, a revised regulatory 6 analysis, has been prepared. The ACRS subcommittee that I 7 reviewed this issue with several weeks ago has been provided
| |
| , 8 copies of this. We briefed the subcommittee, and we did have 9 a meeting with the CRGR on September 9th to discuss the 10 proposed resolution. Agreement was reached to proceed with 1
| |
| 11 the recommended actions with also an understanding that the 12 Reg Guide and SRP implementation wording would be revised to 13 more clearly reflect the intent of the regulatory changes.
| |
| 14 [ Slide.)
| |
| 15 The revised implementation language is on this sheet j 16 that has been provided to y,ou, gentlemen, and it reads as 17 follows.
| |
| 18 It would be applicable to the construction permit
| |
| ! 19 applications and PDAs that are docketed six months after l i
| |
| j 20 issuance and applications for final design approvals for :
| |
| i 21 standardized designs, which are intended for referencing in j 22 future construction permit applications, which FDAs would not ,
| |
| l 23 have received approval at six months following issuance. l l i I
| |
| 24 Our intent is to make the wording clear, that the 25 resolution of this USI will not be impacting plants under !
| |
| I !
| |
| ! I t
| |
| | |
| 204 1 construction.
| |
| 2 CS11de.3
| |
| ( 3 Page 6 of your handout is a bottomline summary of 4 exactly what our planned resolution is. We plan on issuing 5 the Staff's technical findings, to issue the SRP Section 6 6.2.2., called Revision 4, and Reg Guide 1.82, Revision 1 7 These revisions reflect the technical findings. I have 8 covered with you the applicability of the regulatory l 9 documents, i
| |
| 10 Item 3 is to issue a generic letter for information 11 only to all holders of an operating license or construction 12 permit, that outlines the safety concerns regarding potential 13 debris blockage and recirculation failure. It is suggested, 14 but not required, that the Licensees utilize the Reg Guide as 15 guidance for their conduct of 10 CFR 59 reviews for future 16 plant modifications involving replacement of insulation on 17 primary system piping or equipment.
| |
| I 18 If as a result of NRC Staff review of those Licensee 19 actions associated with this replacement, the Staff decides 20 that either SRP Section 6.2.2, Rev 4 or the Reg Guide criteria 21 should have been applied and the Staff seeks to impose these 22 criteria, then the NRC will treat such action as 23 plant-specific backfits pursuant to 10 CFR 50.59.
| |
| 24 MR. MICHELSON: Could you explain in some other
| |
| ~
| |
| 25 words what that means?
| |
| | |
| 205 t
| |
| 1 MR. SERKIZ: I'll try.
| |
| s 2 If a major changeout of insulation is made, let's
| |
| & 3 say through the course of this conversation a plant that was 4 before predominantly reflective metallic goes to predominantly 5 fibers, that is the major change in the insulation. The 6 Licensee or the person with the construction permit then, 7 under the conditions or terms outlined in 10 CFR 50.59, has to 8 make a safety review to see if indeed there has been a 9 degradation, if you will, of soue safety function implication l 10 or whatever.
| |
| 11 If, upon review of that particular 50.59 evaluation, ,
| |
| i 12 either the inspector for the Region or the Staff feels that j 13 the revised Reg Guide, with the guidance, should have been i
| |
| 14 applied --
| |
| r 15 MR. MICHELSON: Should have been applied to the 16 changeout?
| |
| 17 MR. SERKIZ: Yes, should have been applied to the I 18 changeout. And the Staff then says, "Okay, we would like to !
| |
| r 19 see your results in this fashion" -- I'm paraphrasing this in 7 20 my own words -- "then we will pursue it as a plant-specific r
| |
| 21 backfit action under 50.109. l 22 MR. MICHELSON: Why is it a backfit when the ,
| |
| 23 Applicant comes in and says, "I want to change something," and t
| |
| 24 the Staff says, " Fine, you can change it, but here are the l r
| |
| 25 rules you will have to use if you wish to change to change i
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| I
| |
| -.-,m-- .w - _. - _ . , , . _ . . _ _ _ , - = __
| |
| | |
| 206 1 it?" How is that a backfit?
| |
| 2 MR. SERKIZ: That's not what we're saying here.
| |
| 3 50.59 does not deal with the backfits. As you know, 50.59 4 simply deals in a general way with looking at any change or 5 changeout to see if there is a degradation of some safety 6 function or some change relative to the original design 7 provided.
| |
| i 8 Since we have elected not to proceed with being 9 specific to apply it in terminology of backfit to every plant, 10 selected plants or whatever, we do feel that the guidance 11 provided, which is being provided in a generic letter, is good 12 advice, and we would have to pursue it if there were reasons 13 that were identified, that it warranted the application of 14 this evaluation criteria.
| |
| 15 MR. MICHELSON: I'm trying to figure out what 16 backfit even has to do with this. When you've got something 17 already in operation, everybody is happy with it, and the 18 utility decides it would rather do something else, how can 19 anything involving that change ever be thought of as a 20 backfit. It's not a backfit at all.
| |
| 21 MR. SERKIZ: I guess you can take that view. But 22 other people would take the view that it's a backfit from --
| |
| 23 if the Staff says --
| |
| l 24 MR. MICHELSON: A backfit is when you tell the
| |
| ''N 25 Licensee that he's got to change something, I thought.
| |
| (O l
| |
| | |
| 207 1 MR. SERKIZ: I grant you the point. We'ro not
| |
| , 2 telling him he's got to change anything. We are simply trying 3 to tie the loop down to a plant-specific action.
| |
| 4 MR. REMICK: I see it slightly differently.
| |
| 5 Although it's a Regulatory Guide and therefore doesn't have 6 -r e qui r emen t s , if they impose this Regulatory Guide, Revised 7 Regulatory Guide, on the Applicant, then that is a change in 8 requirements. They have other requirements, too.
| |
| 9 MR. MICHELSON: If the Applicant has decided to 10 change something --
| |
| 11 MR. REMICK: But he has current criteria for that 12 now. He has current guidance.
| |
| 13 MR. MICHELSON: He's already got approval for what
| |
| ) 14 he's got.
| |
| 15 MR. REMICK: That's right. And now you're giving 16 him new requirements.
| |
| 17 MR. MICHELSON: No. He is saying, "I want to change 18 from what you already reviewed and approved. Here's what I 19 wan't to change to." And if you say, " Fine, as long as you do 20 this and this," anything you say isn't a backfit.
| |
| 21 MR. WARD: Carl, when you say, "As long as you do 22 this and this," that has made it a backfit, 23 MR. MICHELSON: No, because he suggested a change.
| |
| 24 Now what he does if he doesn't like what you suggest, and be 25 leaves it the way it is, there's no backfit.
| |
| 1
| |
| | |
| 208 1 MR. LEWIS: Thoro is an official definition of 2 backfit nowadays within this agency.
| |
| 3 MR. MICHELSON: That doesn't seem to fit that 4 definition either.
| |
| 5 MR. LEWIS: I agree with you. It doesn't seem to 6 fit it.
| |
| 7 MR. REED: Let's take the issue of a changeout of 8 steam generators on a PWR. I would assume insulation would 9 mostly be stripped, too.
| |
| 10 MR. SERKIZ: Yes, sir.
| |
| 11 MR. REED: This fits into what you're talking about, .
| |
| 12 doesn't it?
| |
| 13 MR. SERKIZ: It can, yes, 14 MR. MICHELSON: Let's stick with insulation now.
| |
| 15 MR. SERKIZ: Let me come back to this. The first 16 step i s, under 50.59, they make
| |
| * an evaluation, okay. We were .
| |
| r 17 not in a backfit mode or anything, okay.
| |
| i 18 What we are saying here is, following their 19 evaluation under 50.59, the Staff takes issue -- has a
| |
| ?
| |
| 20 difference of opinion, whatever way you want to phrase it, 21 okay, and then decides, okay, that the evaluation criteria in 22 this Regulatory Guide should have been applied -- we're not ,.
| |
| t r
| |
| 23 making any specific requirements to apply this at this stage 24 to Reg Guide, okay; we feel it's good information, and wa are i
| |
| 25 providing it to everybody with all-the associated documents --
| |
| r I
| |
| , t
| |
| - - gy - -
| |
| w -e. r .
| |
| | |
| 209 1 if the Staff then says, "Hoy, you should have dono this, or it
| |
| - 2 should have been " then the Staff is going to have to treat 3 this as a plant-specific backfit action.
| |
| 4 Now the Staff is telling them, "Yes, you should have 5 applied this," and we will treat it as a plant-specific 6 backfit pursuant to the guidelines under 50.109.
| |
| 4 7 MR. MICHELSON: What kind of review can the Staff do 8 without even using your new revisions of the Regulatory 9 Guide? They will do some kind of a common-sense review of 10 what is proposed, wouldn't they, if they didn't-want to use 11 the Guide and therefore get into a backfit argument?
| |
| 12 MR. SERKIZ: But that would never come about until 13 it was brought to somebody's attention, okay? Well, that's 14 maybe a wrong way to phrase it.
| |
| 15 When there is a major changeout of insulation, the 16 utility, the Licensee should handle it by whatever means he's 17 handling it under here, okay, and he does this evaluation, his 18 safety evaluation.
| |
| 19 Let's take a hypothetical case and say the Resident 20 Inspector looks at it and says, "Well, how come you didn't use 21 this?" And you get into one of these domino effects. At some 22 point for that particular plant and/or design, the Staff may 23 say, " Hey, you should have used this instead of intuitive 24 judgment."
| |
| 25 All right. If the Staff should seek, then, to l
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| * I I
| |
| | |
| - ..- -. _-- .~ -.._-_- - -. . - . - . _ _ ~ . __ - - . - - . -
| |
| 210 1 utiliso this and say, "You should have dono it this way," all 2 I'm saying is, we will pursue it as a plant-specific backfit 3 under the guidelines set forth in this.
| |
| 4 MR. REMICK: There's one problem I can see with 5 that. As I recall, Section 50.59, it basically says if you're 6 going to make a change, you must determine if it's an :
| |
| I 7 unreviewed safety hasard. If it is an unreviewed safety f
| |
| 8 hazard, you must review it and submit it to the Staff. If you a;
| |
| i
| |
| ! 9 determine it's'not an unreviewed safety hazard, you can go 10 ahead and do it, and in your annual 50.59 Report to the i
| |
| 11 Commission, you indicate in there that you made that change. ;
| |
| I '
| |
| 12 It-seems to me it would be possible for them to make i
| |
| ! 13 the change, put that in their annual report, and the Staff.may
| |
| ) 14 or may not catch it.
| |
| 15 MR. SERKIZ: I would have to partially agree with P.
| |
| 16 you because of that type of wording. I recently again ,
| |
| 17 reviewed the 50.59 wording, and probably in some cases that 18 would be done that way. ;
| |
| I l
| |
| 19 What we're trying to do by issuing a generic letter f t
| |
| : 20 for information, we are indeed in that generic letter -- we l i
| |
| 4 21 have also pointed out that we feel that you ought to take a }
| |
| 22 look at this.in plants that would have small debris screen j i
| |
| 23 areas, high flow rates, low MPSH margins, what you might term !
| |
| 4 i 24 good common engineering judgment. Lay'it in front of them. ~
| |
| [ 25 We provide.to them the Staff's technical findings. The !
| |
| ! I
| |
| .i l t
| |
| ?
| |
| . .I
| |
| . - _ . . . , _ . _ , _ _ _ -,._ , ,_ .._- -.._,_m. - - , , , _ _ . . . . . . _ - . . , , . , _ - _ _ - , . . . , , - . , , , , ~ ~ _ . . , - - - -
| |
| | |
| i I
| |
| 211 1 Regulatory Cuide itself has ortonsivo appendicos. It's 2 incumbent on them at that point to carry it out in whatever O 3 way they carry out their 50.59s.
| |
| S I guess in response to that question, since we've 5 had off and on a very open dialogue with two of the principal 6 insulation manufactufers, some do and some don't even now.
| |
| l l 7 MR. OKRENT: I apologize if I ask a question that's 8 already been asked, but I'm trying to understand the 9 philosophy that says, if a Licensee makes a change in the 10 plant which the Staff finds is questionable, that i t would be 11 treated as a backfit item. I think that's what the words 12 there say.
| |
| 13 MR. MICHELSON: That's what it says.
| |
| i 14 MR. OKRENT: I don't understand that philosophy.
| |
| I 15 MR. REMICE: Dave, let me just try. I'm not saying 16 that I disagree with you, but I assume that the Licensee in 17 this case has his lier'se, in that he is committed to meeting 18 certain regulatory requirements, the guidance of certain 19 Regulatory Guides or something equivalent.
| |
| 20 MR. SERKIZ: Or the final design analysis.
| |
| 21 MR. KERR: Before we go too far, I would suggest, 22 Professor Okrent did not say he wanted to understand it. He 23 just said he didn't.
| |
| 24 MR. REMICK: Okay, thank you. I can see how you l 25 could interpret it. If this is interpreted as changing the
| |
| , A r
| |
| w t- - t -
| |
| | |
| 212 1 requiromonts in midstream aftor the person has boon lioonsod, 2 that could be considered a backfit. i I
| |
| 3 MR. MICHELSON: Nothing is changing. If you just 4 leave the insulation the way it is, everybody's happy.
| |
| 5 MR. REMICK: That's correct.
| |
| 6 MR. MICHELSON: But he wants to change it now. I 7 think the Gtaff has a right to be unhappy abcut the change 8 without calling it a backfit.
| |
| 9 MR. SEMICK: But which regulatory guidance does he 10 follow?
| |
| 11 MR. MICHELSON: At this point, I think you have to 12 use a case-by-case basis to see what you call it. In this 13 case, the insulation change was never prescribed in any 14 previous guidance, to my knowledge. Some of the problems of 15 insulation change were not previously prescribed.
| |
| 16 MR. REMICK: He probably committed, though, to 17 meeting Reg Guide 1.82, Rev 0.
| |
| 18 MR. MICHELSON: He's committed not to degrade the 19 safety of the plant by making the insulation change. In my 20 opinion, he has to show that he hasn't degraded the system.
| |
| 21 MR. SERKIO: Under 50.59, I think that's a 22 reasonable way of phrasing it.
| |
| 23 MR. MICHELSON: You're on a case-by-case bcsis. The 24 Staff reviews his proposal. If they have problems with it, it 44 25 isn't a backfit. It just says, " Don't make the change."
| |
| | |
| . . -. - _ .= - ._
| |
| i 213 i
| |
| 1 MR. SERKIZ: The reason for inserting the backfit 2 here is, this particular section deals with plant-specific O 3 backfits, and that's why I chose that phraseology.
| |
| 4 If you want to look at backfit in the sense you're s
| |
| 5 discussing it, okay, I understand what you're saying. We will 6 treat this as plant-specific actions on follow-up under the 7 conditions or the guidelines set up by CFR 50.109.
| |
| 8 ME. OKEENT: I don't understand what that last 9 statement means, because in there, there is talk about 10 significant effects on safety and so forth and so on, which 11 are a test for whether a backfit should be done. And I don't 12 see that the backfit provision applies.
| |
| 13 MR. MICHELSON: I don't think it does, either, 14 MR. EBERSOLE: How long does this insulation last?
| |
| 4 15 MR. SERKIZ: Some of it, where you uncover piping, 16 for example, foi inspection during refueling and so on, on a l 17 12 or 18-month period locally it's replaced. Larger sections
| |
| ; 18 on steam generators and so on last considerably longer, if 19 you go into steam generator repair. So you're talking two or 20 four years generally before a complete change-out. I'm giving '
| |
| i 21 you very general time periods.
| |
| I 22 MR. EBERSOLE: Of insulation?
| |
| 23 MR. SERKIZ: Of insulation. Now pladts, because of 24 containment peak loads in the last two or three years have
| |
| 'N 25 been switching to a fibrous type of mat type insulation
| |
| -, , -r- - .,. , , ,
| |
| | |
| 214 1 becauso of the bottor thormal insulating charactoristics.
| |
| 2 MR. WARD: Could I understand if a licensee now has V
| |
| 3 insulation that conforms with Reg Guide --
| |
| 4 MR. SERKIZ: Whatever he's got there.
| |
| 5 MR. WARD: -- 1.82, Revision 0, let's say he wants 1
| |
| 6 to change it for some reason. j 7 MR. SERKIZ: He can no ahead and change it.
| |
| 8 MR. WARD: To conform to Reg Guide 1.82, Revision 0?
| |
| J 9 MR. SERKIZ: Yes. In other words, if he had Brand X j 10 and he replaces it with Brand X that he got a new batch of in, 11 because by doing an identical replacement he would have made 12 no change under the conduct of the review here.
| |
| 13 MR. MICHELSON: That's what you asked. He says same ;
| |
| 14 brand. Just changing out. We're talking about changing from 15 metal to fibrous, I think.
| |
| I 16 MR. SERXIZ: The safety concern that we have drawn i I
| |
| 17 attention to is the 50 percent blockage is not applicable to a !
| |
| l f
| |
| 18 fibrous type insulation. So if the applicant changes to a l 19 fibrous type to cut his containment heat load, he performe an 1 20 evaluation to see what degradation there might be to safety i 21 systems, the design margins he had relative to his original 22 design, et cetera.
| |
| 23 He performs this and puts it on file, if you will. '
| |
| 1 24 He submits it a year later, fine. This particular aspect here i I
| |
| O x/
| |
| 25 is -- if the Staff looks at this, whether it's a year from now i l
| |
| I r
| |
| | |
| 215 1 or within wooks, and fools'that ho should have tokon the s 2 approach specified in the Reg Guide, it's going to follow the 3 rules that are laid down, just like we have rules laid down in 4 50.59, and is going to make a justification and go back, and 5 if we want him indeed to redo this, rejustify it, whatever, we 6 will handle this as a plant-specific action, and if 10 CFR 7 50.109 is called backfit or something akin to it.
| |
| 8 MR. EBERSOLE: What if he has just the old plaster 9 up there; he just wants to keep patching it forever?
| |
| 10 MR. SERKI2: I guess he oun keep doing that. If 11 it's just a local patch job, then it's a patch job.
| |
| 12 MR. MICHELSON: The blookage question with fibrous 13 insulation was the pump bearing and seal cooling system s
| |
| 11 ouestion. If he wishes to introduce fibrous insulation, 15 doesn't he have to now account for that particular question if before he's allowed to make the change? And it happens to be 17 in the new reg guide; it wasn't in the old one, but also, 18 simply an education, a learning process. He now knows.
| |
| 19 So if he wants to make the change now, I think he j
| |
| 20 has to account for that problem and show that it's not a 21 problem.
| |
| 22 MR. SERKIZ: I'll pick up on your term "aocount for 23 it" or make recognition for it. Under the methods or means j 24 that 50.59 reviews are carried out. He does not have to come 25 in for permission to do this.
| |
| l
| |
| | |
| 216 i MR. MICHELSON: Yos. But when he does thin 2 unreviewed safety question determination, he determines that O '
| |
| (s-) 3 there is no unreviewed question. Now, if that's his answer l 4 and it turns out he's wrong, then I don't know what the 5 process is.
| |
| 6 MR. SERKIZ: Let's pick up on that just a minute.
| |
| 7 Let's say you have a major changout, and his determination for 8 whatever reason says it's not a safety, the Staff says yes, 9 it is. We will simply pick it up as a plant-specific and then 10 pursue it to this courts of action.
| |
| 11 MR. MICHELSON: Pursue it under the backfit rule?
| |
| 12 MR. SERKIZ: Maybe backfit actions would be a better 13 term here.
| |
| 14 MR. MICHELSON: I don't see that as a backfit 15 action. That's okay.
| |
| 16 MR. KNIEL: We ha,ve elected not to backfit the 17 requirements to operating plants and plants under l 18 construction. We've done that because we feel 19 deterministically the issue is sufficiently improbable and the 20 value impact is very marginal. So on that basis, we are not 21 requiring operating plants or plants under construction to l
| |
| 22 address this issue specifically. And on that basis, I think l
| |
| l 23 it's consistent with that determination -- the determination 24 that if somebody does make a change and we do make such a N
| |
| l 25 requirement, we are really adding a requirement that he wasn't l
| |
| t l
| |
| l
| |
| | |
| 217 i
| |
| i subjooted to before, c1boit he has changed the design of the l
| |
| 2 plant. But we're adding a requirement that he wasn't 3 previously subjected to, and that's the backfit.
| |
| I 4 I think there's an opening there, and I think even .
| |
| 5 though the Staff has to make the case I think we felt that was i
| |
| 6 a suitable compromise for this situation. I 4 ,
| |
| 7 MR. OKRENT: How improbable does the Staff feel the .
| |
| 8 event is? He said it was sufficiently improbable that he 1
| |
| i 9 didn't have to backfit it.
| |
| r 10 MR. SERKIZ: Dave, the blockage frequency that we j i
| |
| 11 calculated, for example, -- the blockage sequences we f 12 calculated ranged at the upper end on the order of 3 times 10 13 to the minus 5, -- and I'll explain in a minute what drove
| |
| () 14 that up -- and down to numbers of 10 to the minus 6 and less.
| |
| l I
| |
| 15 The numbers, the plant conditions or design features l 16 that drove it into the upper direction, since we studied it 17 parametrically, were driven by the fact that we analyzed plant !
| |
| ?
| |
| 18 parameters where you had a 50-square foot debris screen area. j I
| |
| 19 Couple this with 10,000 gpm recirculation flow rates and ,
| |
| 20 available MPSH margin of one foot. If we took those three [
| |
| i 21 combinations together you would calculate a blockage frequency li 22 that high, and then we also assumed in the regulatory analysis ;
| |
| i 23 that this led to core melt. [
| |
| I 24 MR. OXRENT: That was then what pipe break l i
| |
| 25 frequency? Something larger --
| |
| i
| |
| | |
| 218 1 MR. SERKIZ: Wo looked at large, medium and small.
| |
| s 2 We used the Salem plant as a pilot plant and analyzed all the
| |
| (
| |
| 3 welds in a typical loop. Something like 255 welds in one loop 4 coming up to about 800 welds. So we did a weld size and 5 location distribution, and then also looked at it -- you have 6 to take it a step further because you would calculate so many 7 cubic feet of insulation debris being generated. We assumed 8 that got down to the debris screen, deposited uniformally, did 9 a calculation.
| |
| 10 My reason for stating this is there were very 11 specific boundary conditions that drove that number high.
| |
| 12 Conversely, if you looked at plants that had five foot or 13 more head screen areas of 200 square feet or more, flow areas N
| |
| 14 down to 60,000 HEPM, you'd be well below the 10 to the minus 6 15 frequency of blockage. That's the range.
| |
| 16 MR. EBERSOLE: Let me ask a question. What if you 17 have an old boiler with a donut and the applicant or operator 18 has put tons of this plaster on piping inside, and you unleash 19 a few tons of this when you have some kind of a pipe fault, i
| |
| 20 and it proceeds to go to some of these critically vulnerable 21 pump journals and seals and grinds them to bits?
| |
| 22 MR. SERKIZ: To get to that location it would have 23 to go down into the torus which -- say the blowdown forces 24 would take it down there. If you look at the local velocities l
| |
| [ \ 25 in the torus other than getting close to the RHR suction
| |
| | |
| 219 1 strainers, lot's say within sovoral foot, the recirculation 2 velocities in the torus themselves are fairly low, less than O 3 2/10 of a foot per second, 4 We've got experimental data on this stuff in 5 shredded form that says if you have recirculation velocities 6 less than 2/10 of a foot, it generally will not move or 7 transport. We made the assumption even in boilers that it 8 would transport and do some blockage, get similar blockage 9 numbers.
| |
| 10 You could have some material transported, but in 11 terms of a gross transport, I would say that probably would 12 not occur.
| |
| l 13 MR. EBERSOLE: I don't think it takes a gross 14 transport to bind up the journale and seals. As a matter of 15 fact, this little hydroclone that we were talking about 16 earlier today for which there will be no insulation like this 17 to deal with may, if the plaster is at the right specific 18 gravity, tend to drive and thus concentrate the flow into the 19 seals and journais which can't tolerate it.
| |
| 20 MR. SERKIZ: As I indicated before, you can have 21 degradation of the sesis. We don't feel there will be a 22 significant degradation of the pump's operation or capacity to 23 keep pumping; in other words, moving fluid through there. I 24 do not disagree with you; you may not have a degradation of 25 the seal systems.
| |
| l i
| |
| l
| |
| | |
| 220 1 MR. EBERSOLE: I thought some of theso wore both 2 water lubricated and water cooled.
| |
| 3 MR. SERKIZ: Some are, and we were not able to make 4 a clean generic case distinction, and we put some words very 5 specifically in the Reg Guide in the boiler section that 6 people should look at these, particularly on these multi-stage 7 bearing pumps.
| |
| 8 MR. MICHELSON: But if they want to change out --
| |
| 9 and that's really what we're talking about here -- they don't
| |
| }
| |
| 10 have to consider this question at all because it was not in 11 the old reg guide.
| |
| 12 MR. SERKIZ: Theoretically speaking, that's correct.
| |
| 13 MR. MICHELSON: I think what you'rw saying is you do
| |
| , ) 14 not have to consider this question of the seal failures in 15 . deciding whether or not you have an unresolved safety issue.
| |
| 16 You know, the utility when he makes his unresolved safety 17 question determination does not have to include this issue 18 because it's not in the old reg guide.
| |
| {
| |
| 19 MR. SERKIZ: If they elect to take that position !
| |
| 20 guess they could. It would be a very shortsighted one.
| |
| 21 MR. MICHELSON: It would be, but I think fully 22 acceptable from the regulatory viewpoint, isn't it, unless you l 23 wish to raise it as a backfit issue. ,
| |
| 24 MR. SERKIZ: Yes, sir. ;
| |
| 25 MR. MICHELSON: I think that's what you're forced f y
| |
| L
| |
| | |
| 221 1 into; if you want to fight it you must fight it as a backfit S 2 issue.
| |
| 3 MR. SERKIZ: That's correct, sir.
| |
| 4 MR. MICHELSON: Thank you.
| |
| 5 MR. WARD: I guess I am not sure where those of you 6 who are concerned with the definition here -- do you think the 7 reg guide and the resolution here is acceptable, or do you 8 have some change you want to suggest?
| |
| 9 MR. MICHELSON: The reg guide is fine for future 10 plants. These funny words weren't a part of the reg guide, as 11 I recall.
| |
| 12 MR. WARD: It's part of the resolution of the issue.
| |
| 13 MR. MICHELSON: Not a part of the reg guide.
| |
| 14 MR. SERKIZ: Funny words, whatever. The
| |
| . 15 implementation words --
| |
| 16 MR. MICHELSON: No, no, the words that said that 17 this is treated as a backfit issue, et cetera, was that in the i
| |
| 18 reg guide? I missed it.
| |
| 19 MR. SERKIZ: No, sir. These words that are in Item 20 3 are included in the generic letter inat will be sent to all 21 people. That brings the issue to their attention.
| |
| 22 MR. MICHELSON: It's those words I have problems 23 with; not the reg guide.
| |
| 24 MR. MOELLER: It would not be proper simply to say 25 we will treat such an action pursuant to 10 CFR 50.109,
| |
| | |
| 222 1 doloting "as a plant-spocific backfit"?
| |
| 2 MR. MICHELSON: That's playing with words.
| |
| O, 3 MR. SERKIZ: That's what I tried to propose; 4 possibly substituting "backfit" with " plant-specific actions 5 pursuant to 10 CFR 50.109."
| |
| 6 MR. MICHELSON: What needs to be said is it will be 7 treated on a case by case basis, which means in each case the B NRC will review and make a decision based on common sense, I 9 hope, 10 MR. MARK: Do you get notice of stuff being done 11 under 50.59, not necessarily until it's all finished?
| |
| l 12 MR. MICHELSON: No one reviewed safety questions 13 MR. SIESS: It goes in an annual report.
| |
| -m m, 14 MR. SERKIZ: In today's climate, no utility in its 15 right mind is going to do anything without telling the NRC 16 about it, whether it's in the regulations or not.
| |
| 17 MR. MARK: The resident inspector might notice.
| |
| 18 MR. SERKIZ: I think where you might pick it up, the 19 resident inspector would pick this up and bring it either to 20 the Staff's attention at headquarters or regional attention.
| |
| 21 MR. MICHELSON: My objection is treating it under 22 the backfit rule; I think it ought to be treated on a case by 23 case basis. That's my position.
| |
| 4 24 MR. SERKIZ: We are treating it case by case, but we 25 also are subject to rules that we all live by, and the rules
| |
| | |
| 223 1 cro 50.109.
| |
| 2 MR. MICHELSON: That's wl.ere we differ. I don't see 3 where that rule fits this situation. You haven't really 4 convinced me that there's an argument on why that rule fits 5 this situation. I've heard the arguments.
| |
| 6 MR. WARD: The committee is going to have to write a 7 letter on this, and we have a question why. Karl, do you have 8 a suggested change to this informational letter?
| |
| 9 MR. MICHELSON: I thought I made it very clear that l
| |
| 10 1 don't think it applied to -- 50.109 oven applies to a 11 situation like this, and that is just a design change proposed 12 by the utility and it's reviewed by the NRC but never ever 13 considered a backfit. When you consider it a backfit, there D
| |
| 14 are some special things that you have got to do. There's a l
| |
| 15 whole bunch of hcops you've got to jump through, and that 16 seems unnecessary or unwise in a case like this where we are 17 not asking the utility to change anything. He is wanting to 18 change something and it should be a common sense, case by case 19 examination of the problem. Which I thought was the way all 20 changes were handled anyway when a utility comes in with them.
| |
| 21 MR. WARD: That's what the backfit rule is all 22 about, though, to provide a basis --
| |
| 23 MR. MICHELSON: I think the rule is to protect the 24 utility from the NRC coming in and saying you can't do this,
| |
| } 25 can't do that, and make a change. No change is necessary
| |
| | |
| 224 1 horo. Tho utility decidad, not NRC decided, that they wanted 2 to do something, and when they do they just tell the NRC what O
| |
| %- 3 it is and then a safety determination is made and the change 4 is authorized. h7t under the backfit rule which has all these 5 extra little hoops t, jump through.
| |
| 6 MR. OKRENT: I *hink this is philosophically unsound 7 and the committee should reject that last clause and propose 8- words like Karl stated.
| |
| ~
| |
| 9 MR. MICHELSON: We can't reject it because it's not 10 a part of the guide.
| |
| 11 MR. WARD: It's part of the resolution, though. We 12 can comment on that.
| |
| 13 MR. SIESS: There's a different between telling them
| |
| ) 14 what they must do, which is e backfit, and telling them what 15 they cannot do, which is what the Staff is doing. You can 16 change your insulation but you can't do that --
| |
| 1 17 MR. MICHELSON: You can change your insulation but i
| |
| 18 you must do a safety determination based on some common sense 19 rules, which include for instance thinking about these little l
| |
| i 20 cyclone separators which right now they don't even have to i
| |
| 21 think about. The Staff can only come back into the backfit 22 rule and make them think about it. It just seems irrational 23 to me.
| |
| 24 MR. WARD: Karl, I would like to ask ---I have 4 25 draft letter I'd like to give you a copy of and have you
| |
| | |
| )
| |
| 225 1
| |
| 1 1 doctor it up to your satisfaction and then we can discuss i t l l
| |
| 2 further in that form. Okay?
| |
| O 3 MR. MICHELSON: Okay.
| |
| 4 MR. WARD: Mr. Serkis, do you have anything else?
| |
| 5 MR. SERKIZ: I have no further material.
| |
| 6 MR. WARD: All right, thank you very much.
| |
| l 7 Let's go ahead with our next topic, which is primary B system integrity. I think we start out with a report from ;
| |
| 1 9 Dr. Shewmon.
| |
| t 10 11 t
| |
| 12 I
| |
| 13 i 14 j 15 l 16 17 18 4 19
| |
| . 20 t E
| |
| 21 f T
| |
| 22 .
| |
| I 23 1
| |
| 5
| |
| ! 24 i
| |
| 25 i i
| |
| t i
| |
| {
| |
| .m-r .e-n-----,me-- -e
| |
| * 226 mm/gjw Take 20-1 1 MR. SHEWMON: Early in the year, we wrote a
| |
| ("'T ,
| |
| \- l 2 letter saying that we thought the Staff had done enough 3 on leak before break that it could not be implemented in 4 situations in reactors, but that we would like to have the 5 opportunity to consider the implemtation plans after these 6 had been developed by the Staff.
| |
| 7 The Staff now w' ants to apply this to large 8 primary piping, where it would allow the removal of pipewhip 9 constraints which are ius impediment to observation and 10 inspection of the piping and on the whole it looks like it 11 might be better if they were out.
| |
| 12 For reasons I won't try to explain, the Staff
| |
| () 13 and the lawyers feel that this shouid be done in a change 14 to the standard design criteria for GDC No. 4, and so what 15 we have today is a presenat, ion on this partly because of the 16 fact they are implementing leak before break on some piping L i
| |
| 17 and partly because there has been an interest on why it is i 18 we are coming into change GDC 4. v 19 Without further introduction, I will let Bob 4
| |
| 20 Bosnak go ahead and start the presentations.
| |
| 21 MR. OKRENT: Are we talking about BWRs and PWRs?
| |
| 1 22 MR. BOSNAK: Right now we are going to start i
| |
| 23 on PWRs.
| |
| t 24 '
| |
| MR. OKRENT : But the GDC is going to -- it is I
| |
| ! 25 general?
| |
| | |
| 227 mm 20-2 1 MR. BOSNAK: The narrow scope rule covers only b)
| |
| \s / 2 PWRs. The broad scope rule is intending to cover everything, 3 all items.
| |
| 4 But that is not in place as yet.
| |
| 5 MR, SHEWMON: The Staff has taken the position 6 that leak before break -- I hate to say it can't be applied 7 to PWRs, because we talked this morning as if it were 8 relevant there, but I think we will let him talk about it.
| |
| 9 MR. BOSNAK: This is to give you a brief overview 10 of what we are going to try to cover.
| |
| 11 I will sta.it with the introduction as to where 12 we are, a little bit of history.
| |
| (') 13 John O'Brien from resea'rch will get into where the 14 rules change stands. This is both the limited Dr. Okrent 15 mentioned and the broad scope rule.
| |
| 16 Then, we are going to try to cover a little bit 17 of foreign practice. Ray Klacker was taken ill and won't 18 be here. I will get into what specific plant actions the 19 Staff has taken already on PWR main loop, and get into 30 arbitrary and immediate breaks, and finally two proposals 21 that we have had that we consider to be of interest and 22 we would like to get the Committee's reaction.
| |
| 23 MR. EBERSOLE: Before we get out of the sight 24 of the previous topic, would a dynamic effect be considered fx O, # that of blowing off insulation from the pipe break?
| |
| | |
| .. .~. - ---- , . _. . _ _
| |
| 228 mm 20-3 1 MR. BOSNAK: Would you repeat the question?
| |
| ('
| |
| 2 MR. EBERSOLE: The topic we had just up had to 3 do with the dynamic effect that obtains the blowing away 4 of insulation off the piping. Is that a dynamic effect?
| |
| 5 MR. BOSNAK: It is a dynamic effect. Foregone.
| |
| 6 In other words, jets, they are gone.
| |
| 7 - MR. EBERSOLE: That is what knocks all this a insulation off that we just spent about an hour talking 9 about.
| |
| 10 See how ambiguous this business _gets?
| |
| 11 MR. SHEWMON: Give him some time and you will 12 see what he is talking about.
| |
| ( ) 13 MR. WARD: This ought to make you feel better, not
| |
| : 14 worse, Jesse.
| |
| 15 (Slide.)
| |
| 16 MR. BOSNAK: I would like to take you back to 17 your letter of June 14,'1983, 18 This ~is the last time that we met with the i
| |
| 19 Committee. We have had meetings with several of the full 20 Committee, but at that point, pulling time, and in your 21 letter you indicated that provided we can show that there 22 is a' stable crack size by fracture mechanics techniques 23 and that leakage detection is available with sufficient
| |
| ('"; 24 margin, before the crack becomes unstable and runs, then i
| |
| 25 we can go ahead, i
| |
| 1 l
| |
| 1
| |
| | |
| 229 mm 20-4.
| |
| 1 And basically we had all of this in place at O' 2 that time for the PWR primary loop.
| |
| 3 I am not talking aoout branch lines; I am talking 4 about the large diameter heavy PWR primary loop piping.
| |
| 5 I think at the time we were here the work had 6 been done probabilistically and deterministically.
| |
| r 7 Probabilistically by Livermore for Westinghouse, 8 and by the Staff deterministically based on reports that 9 were submitted by hestinghcuse.
| |
| 10 And since then we have gone through several of 11 the other vendors on a vendor-by-vendor basis .
| |
| 12 One of the caveats that we had, that we would
| |
| () 13 like to dwell on a little bit later is heavy component 14 support integrity.
| |
| 15 You also ask- that we advise the ACRS of any 16 regulation changes, and that is what we are going to do 17 today, and position for foreign regulatory bodies.
| |
| 18 You did have another caveat which said before 19 you would send this to operating plants, there should be 80 some clear assurance of quality of design and construction, 21 so that if the history of your letter and where we think 22 we are with respect to going ahead from that point in time.
| |
| I 23 (Slide.) .
| |
| l 24 l
| |
| ' When all the discussion started-on leak before 1 f'~s% -} !
| |
| 25 break, the technical staff believed that it was possible l
| |
| l i
| |
| | |
| mm 20-5 230 i l
| |
| 1 to move forward without making a change to the regulations.
| |
| (/s_ 2 There was much discussion on this back and forth, 3 and OELD had quite a bit of input.
| |
| 4 They felt that there needed to be a change to 5 the regulations primarily because they felt if we did not do 6 it it would be a violation of Administrative Procedures Act..
| |
| 7 and that we were making rules by exemption.
| |
| 8 So, they felt that a change was necessary. So 9 what the Staff is doing now, we will identify the plants to 10 which the schedule of exemptions apply.
| |
| 11 Once we have determined that leak before break 12 performance has been established, and that is via mechanics
| |
| /~s
| |
| ( ) 13 techniques, and again we are talking about PWR main loops 14 only, and leakage detection is in place, these are the things 15 that we can eliminate.
| |
| 16 The dynamic loading effect. And we are talking 17 about pipewhip. jet impingement, and again if we are talking 18 about. jet impingement, we are talking about the f act that 19 it can affect insulation, to answer Dr. Ebersole's que ion.
| |
| 20 A symetric pressurization transients which wa
| |
| : 21. USIA2, that remember started back,in 1975, when one of the 22 vendors came in -- in fact, it was on North Anna -- and 23 indicated as far as their calculational techniques were 24
| |
| /g concerned, that they now were aware of pressurization b 25 transients that gave us a Delta-P within the reactor vessel, i
| |
| t k
| |
| | |
| . ~ . --_ _ - . .
| |
| 231 mm 20-6 1 and a Delta-P outside of the reactor vessel in the associated
| |
| (~h
| |
| \ss/ 2 cavity. On those forces, they were very short dynamic 3 forces that were not considered before. That is how we 4 started on the unresolved safety issue A2.
| |
| 5 Break associated dynamic transients and unbroken
| |
| :6 portions of the main loop and connected branch lines.
| |
| 7 Those are the things that can be eliminated.
| |
| 8 Now, what cannot be changed, and I think the key here is 9 what we are trying to do is we are trying to get rid of ,
| |
| . 10 whip restraint structures and jet impingement barriers.
| |
| 11 Everyone' I believe feels' that they may decrease safety 12 rather than improve safety.
| |
| l i
| |
| () 13 MR. OKRENT: Who is the, ' everyone, ' ,when you 14 say everyone?
| |
| 15 MR. BOSNAK: Most of the' Staff, the technical 16 staff.
| |
| 17 MR. OKRENT: I just wanted to know.
| |
| a 18 MR. BOSNAK: All of the peer review groups 19 that were involved in the piping review committee.
| |
| 20 MR. OKRENT: I was trying to understand.
| |
| 21 MR. BOSNAK: We have heard of no one that has Et said that whip restraint structure and jet impingement 23 barriers, per.se , are going to increase safety and
| |
| ; g- 24 improve safety.
| |
| (S) 26
| |
| ~ These are from both deterministic and probabilistic f
| |
| ., , - - - - .n,- . , . . - - - - , , . - - - ,
| |
| | |
| 232 20-7 mm I studies.
| |
| 2 MR. OKRENT: Are you including foreign groups 3 .in that statement?
| |
| 4 MR. BOSNAK: Certain foreign groups, as well as 5 -- and John O'Brien will get to which ones, and where.
| |
| a Particularly, the Germans and the Italians.
| |
| 7 Others are considering this same approach. Again, it is 8 on a limited' basis going forward only with the PWR main loop 9 where .you feel that there is a very good basis that we are 10 not going to have a. guillotine, instantaneous, guillotine it' double-ended break.
| |
| 12 MR..MICHELSON: I am.having a real problem of.
| |
| (h
| |
| () 13 making sure I understand what you are 'considering . You are 14 removing the dynamic unloading effects. What size breaks is are you'now postulating, since you have eliminated the kind 16 that develop jets -- I guess that eliminates all splits.
| |
| 17 MR. BOSNAK: If you have eliminated in the loop, 1
| |
| .! 18 you still have the branch lines. The branch lines have 19 not been eliminated.
| |
| 30 MR. MICHELSON: Let's stick with'the main loop 21 where you are making your assumptions. In the main loop 22 you are not going to get anything but small leaks, is that 23 correct?-
| |
| 24 MR. DOSNAK: In the main loop you are no going i
| |
| 25 to get a large break.
| |
| | |
| 20-8-mm 233 1 Ilowever --
| |
| / \
| |
| '\ - 2 MR. MICHELSON: Wait a minute then. How big a 3 break are you going to'get is my question.
| |
| 4 MR. BOSNAK: We -have not gotten into the other 5 area --
| |
| 6 MR. MICHELSON: Just on the main loop now, now 7 on the branch line. . From the. main loop, what is - the 8 biggest break you are going to get, or is it just a leak?
| |
| 9 MR. BOSNAK: It is going to be a leak and it 10 is of the order of -- to be able to detect 1 gpm within 11 one hour.
| |
| 12 MR. MICHELSON: It is just a drip, in other b( j 13 words.
| |
| 14 MR. SIIEWMON : You have to be a real operating 15 engineer to consider a gallon a minute a drip. I guess 1
| |
| 16 if you are an engineer you do.
| |
| 17 MR. MICHELSON: You are eliminating all breaks i
| |
| 18 on the main line except for these little dribbles.
| |
| 19 MR. BOSNAK: That is correct, with the exception of '
| |
| 20 the branch line. '-
| |
| 21 MR. MICHELSON: But you are not going to go back 22 and change any of the ECCS design even though there is no 23 other pipe anywhere as big as the main loop, and that was-24 the basis for selecting the main-loop. !
| |
| (~J')
| |
| \
| |
| 25 MR. BOSNAK: We are not changing ECCS. We are !
| |
| i I
| |
| | |
| 20-9-mm 234 1 not changing equipment qualification.
| |
| (~%
| |
| \~ 2 MR. MICHELSON: What is your rationale for not 3 changing these other things, since you have eliminated the 4 breaks that were the basis for the ECCS.
| |
| 5 MR. BOSNAK: The rationale might be defense in
| |
| ! 6 depth.
| |
| 7 MR. MICHELSON: On that rationale, I might want a to ask some other -- you 'know it might be nice to assume 9 jets and bigger breaks for defense in depth, too.
| |
| 10 MR. BOSNAK: Again, we are only talking about the 4
| |
| 11 primary loop. There are other things that can provide 12 sources of leaks.
| |
| () 13 You have manhole covers, you have various things 14 that can provide sources of leaks, so rather than get into is all sorts of mechanistic scenarios, we are staying with is the non-mechanistic, if you like, scenario which says you 17 are not changing containment designs.
| |
| 18 You are not going to change ECCS and y7u are not 19 going to change the equipment qualification, the profile.
| |
| l 20 MR. REED: Let's for a minute hit something related 21 to containment design, and see whether that would be changed.
| |
| 22 There is a great deal of argument going on about Appendix J, i 23 and full pressure containment testing. 2 f-wi 24 LIf you eliminate these large breaks, the i
| |
| %) 25 accident analysis will generally probably show that you I i
| |
| i
| |
| | |
| 20-10-mm 235
| |
| -s 1 don't achieve full pressure. You are going to achieve
| |
| -) 2 part pressure .
| |
| 3 MR. BOSNAK: That is correct, but we are not 4 changing on that basis.
| |
| 5 MR. REED: You are not going to allow Appendix J 6 testing to stay at pipe pressure testing?
| |
| 7 MR. BOSNAK: The answer is we are making no 8 change.
| |
| 9 MR. REED : That would seem that it should be 10 changed.
| |
| 11 MR. BOSNAK: We have gotten comments -- by the 12 way, the rule was published I believe the first of July and
| |
| () 13 we have gotten eleven comments so far.
| |
| 14 There was a comment on doing something with the 15 environmental profile. That was 'a comment that was received.
| |
| 16 It would be along the same lines that you are suggesting 17 I believe, but that is where we are with respect to how we 18 are implementing on the schedule basis the exemptions for 19 the various plants.
| |
| 20 End 20, 21 (Joe W was i typist.) 22 23 24
| |
| \
| |
| 26
| |
| | |
| 236
| |
| #21-SueW 1 MR. OKRENT: Excuse me. Are you going to g
| |
| \s- 2 discuss the quality, how would you assess the quality 3 at the plants? Remember that item in the ACRS letter?
| |
| 4 MR. BOSNAK: Correct.
| |
| 5 MR. OKRENT: Were you going to discuss that?
| |
| 6 MR. BOSNAK: Right now we are stayingiwith 7 the primary loop.
| |
| 8 MR. OKRENT: That's right. I'm talking about 9 the primary loop.
| |
| 7 10 MR. BOSNAK: We are saying that the primary 11 loop -- I think what -- the way we interpreted the ACRS 12 letter was that if we went into older plants where the
| |
| () 13 quality of construction, the chance for perhaps some 14 errors was not as good as what we had today, that we 15 should make sure that we,are satisfied with the quality 16 of construction.
| |
| 17 That's the way we interpreted that letter.
| |
| 18 MR. OKRENT: And I'm trying to ascertain with 18 l the primary loop, are you trying to ascertain the quality 30 of the primary loop?
| |
| 21 MR. BOSNAK: On the basis of our experience 22 i with the primary loop, we don't feel that there are 23 quality problems when we are -- again discussing the loco.
| |
| 24 When you start getting into other areas, it becomes more f''/
| |
| \_
| |
| )
| |
| 25 of a problem.
| |
| | |
| 237 i
| |
| #21-2-SueW 1 MR. OKRENT: What is your basis for -- let's l'D
| |
| (_s/ 2 take a plant like San Onofre 1 or Connecticutt Yankee, 3 which I think was designed and fabricated for -- we started 4 instituting much of the improved quality in primary systems 5 and in-service inspection and pre-service -- you know, 6 different kinds of inspection, pre-service and so forth 7 where there may have been less control on welds, material 8 in the field, et cetera, et cetera, how do you ascertain 8 the quality of the primary loop?
| |
| 10 Well, I don't even know if all welds in the 11 primary system are inspectable for some of the older plants, 12 whether they would be, or the-newer ones.
| |
| 1
| |
| () 13 MR. BOSNAK: Again, we do have whatever as-14 surance that you have from the factory' mechanics bases 15 that given that you have a crack or a flaw, that is it-16 going-to be able to propagate.
| |
| 17 MR. OKRENT: But they assume, for example, in 18 fracture mechanics they have to assume some material 19 properties.
| |
| 20 MR. BOSNAK: Correct.
| |
| 21 MR. OKRENT: If there wasn't good control on i '" weld rod, they don't know what the material is.
| |
| 23 MR. BOSNAK: Even so, the basis is that even
| |
| " if you have all of those uncertainties you are going to
| |
| (~S
| |
| \.
| |
| 25 get a leak before you have a break.
| |
| l l
| |
| | |
| 238
| |
| #21-3-SueW 1 MR. OKRENT: You have to show me that basis.
| |
| .r
| |
| \_ h/ 2 MR. SIESS: Have you got a couple of days to 3 spare?
| |
| 4 MR. BOSNAK: That again is based on the 5 deterministic work that was done, the probability of having 6 a break and the probabilistic work that was done. You 7 are talking about -- again if you are talking about direct 8 effects, you are talking about ten to the minus thirteenth 9 for a break, the probability of having such a break.
| |
| 10 And even if there were several low orders of 11 magnitude of uncertainty on that, it still represents 12 an almost incredible event.
| |
| O g j 13 MR. OKRENT: There is a well known concept in 14 civil engineering-that bridges and structures will never is fail if you analyze them probabilistically.
| |
| 16 The difficulty is when they fail it's due to 17 something that wasn't in the probabilistic analysis, and 18 they do fail from time to time.
| |
| 19 MR. SIESS: I disagree with the first preposition, 20 not the second.
| |
| 21 MR. BOSNAK: We are saying the assurance is 22 here for these systems now that we are talking about. If 23 they are going to leak --
| |
| 24 MR. SIESS:
| |
| l (~%j They will fail but they won't l \_/ '
| |
| 25 fail' catastrophically.
| |
| | |
| .. -. . . -_ .. = -._ . - - .__ . .
| |
| 239 i
| |
| #21-4-SueW 1 MR. BOSNAK: Even if you wanted to get into 2 a failure scenario, how can we be sure that the massive 3 steel structures-that we have in there are put in at the 4
| |
| 4 right place?
| |
| 1 5 MR. OKRENT: I'm looking at the Staff's logic, 6
| |
| and'-I'm looking at the specific comment that the ACRS 7 letter had concerning~ older plants.
| |
| 8 And I have not heard anything.that you have done i 9 to assess why the older plants are okay. For example, I l L
| |
| 10 have heard ~ people mention possible troubles --
| |
| 11 MR. BOSNAK: The older plants are not going to -
| |
| I
| |
| ; 12 be'taking anything out. .The older plants are going to stay
| |
| () 13 ' with what they have.
| |
| 14 ' 'The older plants, and this is USI A-2 -- and 2 aren't going to have to put'in additional steel to take j i
| |
| 16 care of the asymmetric pressure loads. That is what is i
| |
| 17 happening with the older plants. ;
| |
| 18 The older. plants are there. We are not going i i
| |
| 19 to take anything out.- The ones_that are of the vintage [
| |
| i 30 that you are talking about in the Westinghouse Owners ;
| |
| j t 1BI Group are just not going to have to put in additional ,
| |
| Et steel for the asymmetric pressure transients, A-2. j 23 MR.'OKRENT: ' I have no objection to their not )
| |
| v 24 putting in additional 2 steel (or the asymmetric --
| |
| lE MR. SHEWMAN: What will come out of plants? !
| |
| I
| |
| | |
| 240-
| |
| #21-5-SueW 1 MR. OKRENT: What vintage will you start
| |
| 's- 2 taking things out?
| |
| 3 MR. BOSNAK: We are talking about the Westinghous e 4 A-2 facilities. There are sixteen plants.
| |
| 5 We said that the review is complete for Cook 1 6 and 2, Ginna and Point Beach. The other two facilities 7 have not responded as yet, probably because they are wait-8 ing for the. rule to go through. .
| |
| 8 (Slide.)
| |
| I 14 What they have to do now if they wanted to come 11 in at the present time would be to come in with a value 12 impact type study.
| |
| ( 13 MR. OKRE!;T: And must Ginna and Point Beach 14 come right into the next wave after san Onofre 1 and 15 Connecticutt Yankee, that happens to be good timing.
| |
| 16 MR. BOSNAK: We are talking again about -- we 17 are talking about Issue A-2. The newer plants -- and 18 that's what I want, as you get down to -- these are the 18 NTOLs. We are talking about a different situation.
| |
| 20 So you are kind of mixing up apples an6 oranges to a certain degree. The old plants are not -- we are not 22 proposing at the present time to do anything with respect 23 to taking things out.
| |
| ( ') What they really need is, as far as that Issue
| |
| \_/ :
| |
| A-2 is concerned, asymmetric pressure transient, to get
| |
| | |
| n-241 .j
| |
| #21-6-SueW 1 rid of that particular problem and have to do it. That's n
| |
| V 2 what we are talking about.
| |
| 3 Now, for instance, the combustion engineering 4 plants, the old plants, in order fo get rid of it they 5 can take advantage of the decoupling of SSE and LOCA.
| |
| 6 The B&W plants do not need either. The old plants, in 7 order to resolve the Issue A-2, they do not need eitl'er 8 because they can handle both events.
| |
| 9 Now, down into the combustion engineering these 10 are the newer plants. The Staff has completed its rsview, 11 and it was done on Palo Verde. It was done recently with 12 a letter to CE not too long ago.
| |
| 13 B&W review is underway and GESSAR II review 14 is underway. They have not been completed.
| |
| 15 You said GESSAR MR. EBERSOLE: ,
| |
| Wait a minute.
| |
| 16 II. I thought this was applying just to PWRs without 17 stress corrosion' cracking problem.
| |
| 18 MR. BOSNAK: This is for a situation which 19 theoretically you don't have stress corrosion cracking
| |
| # because you are starting out with nuclear grade material.
| |
| 21 MR. EBERSOLE: Okay. The premise is that pipe 22 is just as good as a BWR.
| |
| 23 MR. DOSNAK: Obviously this rule which covers N
| |
| only PWR main loops would not apply to GESSAR II. But it 25 I was put up here to be complete.
| |
| | |
| 242
| |
| #21-7-SueW 1 MR. EBERSOLE: You are talking about new GE
| |
| (~
| |
| i \~ 2 loops?.
| |
| 3 MR. BOSNAK: That's correct, when it's done.
| |
| 4 But the work is still under review.
| |
| 5 MR. SHEWMAN: Where will the pipe -- where will the 6 pipe whip restrain question come up? Is that with this 7 next-group of plants you've got?
| |
| 8 MR. BOSNAK: Yes. We are talking about now the 8 NTOLs. I think all of these, some of them have already 10 started operating.
| |
| 11 The exemptions which were granted, and we 12 checked nere before we came down, I think these are correct.
| |
| () 13 .This indicates that the technical work is complete, that 14 the Staff, the Technical Staff, has gone through on.their i
| |
| 15 fracture mechanics approach and is in agreement that they 16 have demonstrated leak before break performance. ,
| |
| 17 This would be the formal exemption that is given 18 not to comply with GDC 4 with respect to, in this case we 18 are talking about only jet impingement shields. In other
| |
| " cases, it would be if they haven't shimmed up for the 21 pipe for a pipe whip restraint they might not have to do I
| |
| " l that.
| |
| 23 The scheduled exemptions were given for a
| |
| () 24 25 period cf time I think to the eighteenth month after the Is that right? Second refueling.
| |
| first refueling I believe.
| |
| | |
| 1 243
| |
| /
| |
| .-.#21-8-SueW- 1 So that by that time, ELD believes-that the
| |
| /
| |
| 6
| |
| ; \s 2 rule should be in place, that then they can go ahead and 3 remove other things if they so desire.
| |
| ; 4 But currently as they receive their 31 cense, 5 there is a specific request made for exemption. In some 6 plants -it was rather quite specific as you see here.
| |
| 7 So things were installed and there was nothing that was 8
| |
| removed and these were then all of the NTOLs that have i
| |
| 8 applied and been granted exemptions.
| |
| 10 Now there are other applications that we did 11 want to bring to your attention. Prmbrie Island and Indian '
| |
| 12 Point, and for those they are different than these obviously I
| |
| O I
| |
| ( ,1 13 The review is underway. We have gotten several 14 i
| |
| submissions from particularly the PWR owners to carry this is thing forward beyond main loop, to go to things like 16 pressurizer surge lines, accumulator injection lines and 17 other areas. Also, Nine Mile has requested. secondary lines.
| |
| 18 And all of these are -- there.is no action 18
| |
| } taking place on them. They are just pending.
| |
| 20 MR. OKRENT: At some point, are you going to 21 tell us what.it is that you are proposing to do in a 22 j generic way? What you are proposing to permit in a 23 -
| |
| generic way?
| |
| t
| |
| () '
| |
| 26 MR. BOSNAK: When you say generic, do you mean across the board, not just -- in other wordo, you would like ,
| |
| i
| |
| .-.,m--- - - - , - - , ~ , - , .- - - - - , - -- - - , - - , ,-
| |
| | |
| . -. . . . = _..
| |
| 244
| |
| #.21-9-SueW.1 to know the difference between the limited scope and the 52
| |
| % 2 broad scope?
| |
| 3 MR. OKRENT: No. I mean in the limited scope.
| |
| 4 MR. BOSNAK: I guess the question is, what do 5 you mean by generic?
| |
| 6 MR. OKRENT: It's applicable to a class of 7 plant, all PWRs or all PWRs built after -- according to 8 a certain ASME Code. Okay. That makes it generic. That 8 applies to a class of plants. t 10 MR. BOSNAK: The limited scope rule is applicable j
| |
| , 11 to all PWR main loops.
| |
| 12 MR. OKRENT: What does this permit?
| |
| n, g ,, 13 MR. BOSNAK: It would permit if they can 14 demonstrate leak before break performance that you could 2 eliminate all of the things that I had on the previous is slide. We are talking about basically jet impingement i
| |
| 17 and pipe whip restraint.
| |
| I8 MR. SIESS: Some pipe whip restraints simply.
| |
| 8 limit movement. That is, they have appearance.
| |
| 30 MR. BOSNAK: That's correct.
| |
| 21
| |
| , MR. SIESS: Are there also pipewhip restraints 22 l that have snubbers?
| |
| MR. BOSNAK: There are snubbers that are 24 placed in a line to take care of dynamic loads. And to
| |
| )
| |
| that sense --
| |
| t
| |
| -3 - - - - ,.-v-m - . , - . _ a vm.- . . - -.
| |
| .c. e , e e 4 -- - y
| |
| | |
| I 245'
| |
| #21-10-SueM MR. SIESS: On the last page, it mentions
| |
| /\
| |
| I 2 snubbers at Crystal River.
| |
| 3 MR. BOSNAK: I'm going to get to that.
| |
| 4 MR. SIESS: Are those pipewhip restraints, or 5 are those snubbers for seismic? When you say dynamic 6 lo' ads seismic --
| |
| l 7 MR. BOSNAK: They are there for several 8 purposes. They are there for seismic and pipe break 9 loads.
| |
| 10 However,.the larger load of all the governing 11 load is the pipe break load.
| |
| 12 MR. SIESS: Okay.
| |
| 13 MR. BOSNAK: I think maybe at this point, it 14 would be good to have John O'Brien come up and get into I
| |
| is the status of the rule change and what is going on with 16 respect to foreign governments.
| |
| j 17 MR. REED: I think I have one concern. I'm 18 certainly convinced after following PWR main loop per-19 formance and testing for cracking and all these kind of I
| |
| # things that there isn't a particular problem with some 21
| |
| . fracture of PWRs.
| |
| j 22 But you keep mentioning BWRs, and I am worried.
| |
| 23 that by osmosis this might leak over into the BWR field --
| |
| i
| |
| " MR. SHEWMON: Let's keep that in our mind,
| |
| ; 26
| |
| .this is a five minute introduction that has taken half an i
| |
| j
| |
| - - - - - , . * - .- ,,--y r -. _.
| |
| | |
| I' 246 ;
| |
| 1 4 l 21-ll-SueW' 1 hour so far. i y,
| |
| ! 2 MR. BOSNAK: Th'at's why I wanted to got John i
| |
| , 3 up here next to discuss the broad scope rule, where it I
| |
| , 4 stands and what is going on.
| |
| \
| |
| END #21- 5
| |
| .I i 6 L
| |
| 7 i 7 4
| |
| , 8 a
| |
| 9
| |
| {
| |
| 10 l,- 11 j 12 4
| |
| m 14 t
| |
| ', 15
| |
| 't
| |
| ; e k i
| |
| i 16 I 17
| |
| : i. ,
| |
| ! la 4'
| |
| i 19 ~
| |
| i e
| |
| ! 21 s
| |
| b ?
| |
| ! . 22 2
| |
| 1 ,
| |
| N '
| |
| 24 4 -
| |
| )
| |
| - - , . , _ . _ __ _ , _ _ . - _ , - . ~ - . _ - _ . _ , _ _ _ - _ . . - _ , . - . . _ _ . _ . . _ , , _ , _ , _ _ . , - . , _ . - _ _ _ _ _ . _ _ _ , _ . . _ . . _ _ _ _ _ _ _ . _ _
| |
| | |
| ..- - - . .~. .~. . _ ~ . - - _ - - - - - ._. . _- . .. . . . .
| |
| 247 1- tstide.] ,
| |
| 2 MR. O'BRIEN: I want to show you some pipewhip
| |
| .3 restraints on some very large diameter pipes. There is an H 4 section here, these steel straps. There is an H member coming 5 up that way and some connecting structure between the two 6 pipes. There is similar orientation over here. The black 7 small1 diameter members are not part of pipewhip restraint, 8 but that gives an illustration of what a pipewhip restraint
| |
| ! 9 is.
| |
| i 10 We have some crushable high cone here. This is an
| |
| ]
| |
| 11 attempt to illustrate the clutter that results from the use of ,
| |
| , 12 pipewhip restraints.
| |
| P 13 [ Slide.]
| |
| 14 We have two rules on the same subject. The limited 15 scope rule is limited in many ways. It is limited in that it 16 only addresses the main loops of PWRS and also limited in that l
| |
| l 17 only dynamic effects are discussed. That is the only change I 18 anticipated, and we Are shooting to get it in final form some i.
| |
| 19 time in January, i
| |
| 20 The broad scope rule is a slow-moving rule. That's 21 an optimistic schedule right there, January 1986 for the 22 proposal and June for the final. Bob said we got eleven l
| |
| 23 comments. It's up to 19 right now. All the comments support 24 the rule, or the intent of the rule.
| |
| ! 25 [ Slide.)
| |
| i ,)
| |
| i I
| |
| | |
| 248 1 The commonts ocmo frem utilition and vondors, but 2 there is no opposition to the rule. These are some of the i 3 issues raised in the comments, like we were silent in the 4 proposed limited scope rule on environmental qualification. A 5 lot of the commenters told us we should now include 6 environmental qualification, ECCS and containments. In the 7 new broad scope rule, which you may not have seen, we said 4
| |
| 8 this rule introduces an inconsistency in the regulation by i
| |
| 9 only excluding dynamic effects while ignoring other effects, 10 especially with pipe rupture. We make a commitment to study 11 whether fracture mechanics should be applied to ECCS 12 containment and environmental qualification, but we don't 13 indicate when and by whom, but we are going to live with this 1
| |
| l 14 inconsistency right now.
| |
| 15 Only the ACRS was troubled by the definition of the 16 primary system. Everybody else seemed to know it, but we 17 thought we would throw it in. And this is a hot issue.
| |
| 18 People want to modify heavy component supports. They want to i 19 eliminate dynamic effects of postulated pipe ruptures as they 20 impact heavy component supports.
| |
| 21 A careful reading of the proposed limited rule says 22 heavy component support designs are not to be changed. We got 4
| |
| l 23 a lot of comments asking us to do that. I don't know what the 24 resolution of these issues is, by the way. These are just the 25 issues.
| |
| 1
| |
| )
| |
| 1
| |
| | |
| 249 1 MR. SHEWMON: Is thore anything that is rcmovablo?
| |
| 2 If you have to take anything out to inspect it, it is nice if O 3 you don't have to put it back in and then take it out again 4 the next time. But the heavy component supports for a 5 licensed plant are there, aren't they?
| |
| 6 MR. O'BRIEN: No, they are mostly huge numbers.
| |
| 7 There is more than one utility that is affected.
| |
| I 8 MR. SHEWMON: You are saying the snubber is the 9 support.
| |
| 10 MR. O'BRIEN: Yes. It's a heavy component support, 11 huge numbers.
| |
| ! 12 MR. SHEWMON: I think of it as a shock 13 absorber. Nothing you are going to lean on. But if that is I 14 part of your nomenclature --
| |
| l 15 MR. O'BRIEN: It's part of the support system that j i
| |
| 16 supports the component in case of a pipe rupture. '
| |
| 17 MR. MICHELSON: On your definition of primary system ;
| |
| 18 piping, did anyone suggest the same rules and so forth go 19 beyond the large diameter main loop piping, which is the 20 reason we asked for the definition?
| |
| 21 MR. SHEWMON: That is the other part of the agenda.
| |
| j 22 MR. MICHELSON: Okay.
| |
| l 23 MR. SIESS: John, do you mean these multi-term 24 capacity snubbers that I have seen at the bottom of steam l
| |
| i l 25 generators are.therefore pipewhip restraints?
| |
| i i
| |
| 1
| |
| | |
| 250 1 MR. O'ERIEN: No. A pipewhip restraint is a device 4 2 placed near the pipe that only acts when the pipe breaks. If 3 the pipe breaks, that thing is --
| |
| 4 MR SIESS: Those snubbers you are talking about on 5 heavy equipment support, are those there for pipe whip or for l
| |
| 6 seismic' '
| |
| 7 MR. O'BRIEN: If you put them there for pipe break, 8 they are also there for seismic. You can't avoid it.
| |
| 3 9 MR. SIESS: Do you have to have it for seismic?
| |
| 10 MR. O'BRIEN: No. Most plants can get rid of them.
| |
| i 11 If you eliminate the pipe rupture, you can eliminate the i
| |
| 12 snubbers. If the pipewhip restraint acts during an 1
| |
| 13 earthquake, it is an accident that you didn't anticipate. As ;
| |
| 14 a matter of fact, that's one of the reasons we want to got rid d
| |
| 15 of them, is that they could act during an earthquake and give ;
| |
| 16 you impact loads that you did not anticipate. '
| |
| 17 Anyway, somebody pointed out that we used the words
| |
| ! 18 " extremely low" but we didn't define it. In addition, people f
| |
| ' 19 said the use of pipewhip restraints is unnecessary --
| |
| [
| |
| i 20 MR. SHEWMON: Would you move up wnat you are 21 talking about so we can read it? !
| |
| I 22 MR. O'BRIEN: Sorry. People have noted that we said }
| |
| 23 the amendment was an unresolved safety issue and pointed out 24 to us that may not be. We also said you shall not have 25 augmented leak detection. They pointed out that also may i
| |
| I i
| |
| i O
| |
| _ . _ . . . _ _ . , __. _ . . . _ _ .._ _ . _ -..-. _ _ .~ . _ . - -.
| |
| | |
| 251 1 not bo nocossary.
| |
| 2 These are some of the key issues that we have
| |
| \ws# 3 received, and some of the public response to the proposed 4 rule.f 5 MR. OKRENT: It's a segment of the public, I would 6 say.
| |
| 7 MR. O'BRIEN; Everybody was invited; nobody came.
| |
| 8 [ Slide.)
| |
| i 9 Regarding foreign practices, this information comes 10 primarily from surveys that we have undertaken with respect to 11 our Piping Review Committee, and the first four countries on 12 this slide have more or less adopted U.S. practices.
| |
| 13 Particularly France and Japan are very close to what we have 14 been doing. Canada and Sweden have some divergence; however, 15 they are very close. They all have pipewhip restraints, they 16 all have double-ended guill,otine breaks. I understand Canada 17 is now trying or anticipating something to do with a leak-18 before-break technology.
| |
| 19 MR. OKRENT: Let's look at France there a minute.
| |
| 20 What are you saying is the practice in France?
| |
| t
| |
| ) 21 MR. O'BRIEN: Very close to the United States.
| |
| i 22 MR. OKRENT: You mean the current practice. As far 23 as I know, they don't plan to change.
| |
| 24 MR. O'BRIEN: It is hard when you have got a 25 standardized design to change.f l
| |
| | |
| 252 1 MR. OKRENT: I spoko to ano of the Frenchmon 2 responsible in the area, and he didn't see a basis in his t
| |
| 1 l 3 opinion for removing the possibility of a break.
| |
| 4 MR. O'BRIEN: It is hard for them with a 5 standardised design. They are not motivated. That's one of {
| |
| ; i a
| |
| ; 6 the down sides of standardized designs. The British are l 1
| |
| f 7 leaning towards present U.S. practices. They come and talk to 8 us frequently. They are going to put apparently some pipewhip :
| |
| : 4. ,!
| |
| 9 restraints in. ;
| |
| l a
| |
| 10 [ Slide.3
| |
| ) !
| |
| i 11 The interesting cases, however, interesting to us, ;
| |
| I !
| |
| 12 are the Germans. Since 1984 the Germans have continued to j 13 postulate a double-ended circumferential break in the primary I !
| |
| i 14 system for ECCS containment.and equipment, environmental ;
| |
| )
| |
| I 15 qualification of equipment, but they no longer have a t
| |
| l 16 double-ended guillotine break in the main coolant loop and to 17 the surge line and the RHR line either, part of the main 4 l 18 coolant or attached to branch lines or the main steam or main 19 feedwater lines. That is only that portion of the main steam l i
| |
| 20 or main feed inside the containment from the steam generator !
| |
| I 21 to the outside isolation valve, and they also only exclude i i
| |
| -I +
| |
| 22 reaction forces and jet forces, f
| |
| t 4 i 23 Somebody asked earlier, what are we going to replace I
| |
| l 24 this, what kind of break? The answer is sero, nothing. In f i
| |
| 25 our rule we say the pipe doesn't break. There are no reaction f i :
| |
| t l
| |
| l
| |
| | |
| 253 1 forcos at all. Tho Germans have a 10 porcont f1cw rato
| |
| -s 2 MR. OKRENT: Before you leave the Germans, is that 3 something that they are backfitting to old plants or is it 4 something they are applying to plants built after a certain 5 time?
| |
| 6 MR. O'BRIEN: Two plants I know are affected, but I 7 don't believe they are backfitting, no.
| |
| 8 MR. OKRENT: Do they have any special quality a
| |
| 9 control on the primary system that goes beyond what the NRC 10 has?
| |
| 11 MR. O'BRIEN: They have forged fittings, for one 12 thing.
| |
| 13 MR. OKRENT: 1 think you should have that in the 14 picture One should not have to ask about that to find it ,
| |
| a 15 out. ;
| |
| 16 MR. O'BRIEN: I'm sorry. There are a number of 17 things they do. They have to remove snubbers off all their ,
| |
| 18 components and replace them with bumpers. They have double i
| |
| They have forged fittings, and 19 hull piping here and there.
| |
| 20 then the Italians recently switched to the German practice, 4 21 abandoning ours. We don't know what is happening beyond ,
| |
| 22 the Soviet Bloc. ,
| |
| i 23 That is my presentation. .
| |
| I 24 MR. EBERSOLE; Do any of these designs incorporate 25 bendable structural members in both directions which clear t i. e !
| |
| t i
| |
| l l
| |
| | |
| .~- - - . -
| |
| 254 1 pipo but would not as colemic rostraints in both dirootions?
| |
| 2 MR. O'BRIEN: Are you talking about what we call
| |
| \- 3 passive pipe restraints?
| |
| 4 MR. EBERSOLE: I'm talking about pipe restraints in 5 the form of bendable supports which would act in the capacity 6 of current hydraulic or friction snubbers.
| |
| 7 MR. O'BRIEN: You mean flexible bondable?
| |
| 8 MR. EBERSOLE: Not flexible. Take a permanent set.
| |
| , 9 I'm trying to get the damping in. Bending ductile pipe I
| |
| 10 supports.
| |
| 11 MR. 11ESS: Like some of the stuff we saw in the 12 pictures from Chile. They were not intended to be that. I 13 think he is talking about the stuff at EPRI Spence Bush was 14 looking at.
| |
| 15 MR. O'BRIEN' That's what we call passive pipe
| |
| ! 16 restraints. We don't have any of those, to my knowledge.
| |
| 17 MR. EBERSOLE: It would appear they would get rid of 18 some of these nasty problems with snubbers.
| |
| 19 MR. SHEWMON: One utility you had was doing some 20 tests on collapsing a short segment of pipes. Just out out a 21 piece and that would absorb it. I don't know whether it was 22 Duke, but that was a pipe --
| |
| 23 MR. OKRENT: A different area.
| |
| 24 Did you ask why the British, since they are starting 25 afresh, are not accepting the leak-before-break to the primary i
| |
| | |
| -.. - - . _ . - ..=
| |
| 255 i
| |
| i systom?
| |
| 2 MR. O'BRIEN: No. ,
| |
| i 3 MR. OKRENT: It would have been relevant, I think.
| |
| 4 MR. O'BRIEN: I talk to them a lot. They are just 5 adopting our practices. !
| |
| t 6 MR. OKRENT: No. In fact, they thought about it in 7 depth and they have some very specific areas in the primary ,
| |
| t 8 system where they are reluctant to assume leak-before-break. r 9 I think it would have been well to explore it. l 3
| |
| 10 MR. O'BRIEN: We did. We talked to them. Actually, P
| |
| 11 I talked to them and tried to persuade them not to do what l i
| |
| 12 they are doing, but they are doing it anyway. I 13 MR. SHEWMON. Why are they doing what they are l f
| |
| 14 doing? h 15 MR. O'BRIEN: I don't know. It beats me. ;
| |
| i i
| |
| 16 MR. REED: I am trying to remember from my Germany ,
| |
| p 17 visit. Didn't I hear at the meeting that leak before break {
| |
| 18 was not being adopted for political reasons to some extent in f
| |
| : i i
| |
| 19 Germany, and perhaps this could be the case with respect to q
| |
| ' l' 20 England. I'm not sure. !
| |
| I f
| |
| 21 MR. OKRENT: I'm sorry. I think the Germans, in [
| |
| l i
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| 22 fact, as he said, are for new plants in which they are putting '
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| 1
| |
| ?
| |
| 23 really --
| |
| t 24 MR. O'BRIEN: Better quality construction. i I
| |
| 25 MR. OKRENT: Very significantly modified i f
| |
| t I
| |
| i
| |
| | |
| ._. _ _ . - _ _ _ _ _ ~ _
| |
| e 256 i roquiromonts on the primary sysica construction. They aro 4
| |
| 2 proposing just what we showed. The British are concerned in O 3 at least two areas of the primary system about ability to 4 inspect. One is when you are next to a pump.
| |
| 5 MR. O'BRIEN: At the nossle.
| |
| 6 MR. OKRENT: Yes, and there is at least one 7 direction at the pressure vessel where they are concerned 8 about ability to inspect, and it is technical reasons like 9 this that are behind their unwillingness now to buy what you
| |
| ; 10 are proposing for all BWRs without knowing the quality -- in 11 my opinion without knowing the quality of the primary system.
| |
| 12 MR. SHEWMON: The premise of the leak before break, l
| |
| 13 though, is even if you cannot inspect it, it will leak before I
| |
| 14 break and you will have that to tell you when you have got a 15 1arge crack or when you have got a crack.
| |
| 16 MR. OKRENT: It d,e p e n d s on certain assumptions about 17 the material properties in the weld.
| |
| 18 MR. SHEWMON: Yes, of welds that we have samples of 19 or can test.
| |
| l 20 MR. OKRENT: We don't necessarily have samples or 21 can test samples for all plants.
| |
| 22 MR. SHEWMON: I beg your pardon. We know what weld 23 metal it was made out of, we know what flux it was made out 24 of. It may not have been made the same day. In that regard, 25 we have properties on the material and have a pretty good idea l
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| i )
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| l l
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| l
| |
| | |
| 257 1 what it is.
| |
| 2 MR. OKRENT: I would suggest that there has been 3 enough of a history of breakdown in quality control -- I don't 4 mean quality assurance -- over the years. You know, there is 5 some reason to assume that not all primary system welds have 6 the right weld metal.
| |
| 4 7 MR. SHEWMON: I don't know what you mean by right.
| |
| 8 I don't know of any evidence that we have of primary -- of 9 toughness problems in primary welds in pipes. These are 10 things that are out of radiations, so it's not a matter of 11 whether you have two-tenths copper or three-tenths copper, and 12 the tests that they have done and the people have gone back to 13 make the case that the bases for this has been to test these i
| |
| 14 things, and the results are that it is a conservative and
| |
| ; 15 sound approach as far as any evidence I know of.
| |
| I 16 MR. OKRENT: I think the assumption is that it was i
| |
| 17 fabricated as designed, that's all, in all the analysis.
| |
| i 18 MR. SHEWMON: The assumption is that it's fabricated l ,
| |
| 19 out of sound-type material.
| |
| i 20 MR. SIESS: There is no assumption that it's (
| |
| i i
| |
| 21 perfect, is there? ;
| |
| 22 MR. SHEWMON: Few things are in this world, i i
| |
| 23 MR. SIESS: In the calculations they do assume 24 flaws.
| |
| t 1
| |
| 25 MR. SHEWMON: They assume flaws that are bigger than i i
| |
| i 1
| |
| i i
| |
| I
| |
| | |
| h 258 i
| |
| ! 1 cnything anybody has over found. Thoy got btg enough to 1
| |
| '2 leak. The only assumption then is that they don't run beyond f'
| |
| ,f.
| |
| \
| |
| 3 that in a brittle fashion the way this damn guillotine break
| |
| +
| |
| 4 assumption was that we have been saddled with for 40 years or 5 30 or whatever it is.
| |
| 6 Okay. Are you back next, Bobt 7 MR. BOSNAK: Before I get into the arbitrary I
| |
| 8 intermediate breaks, let's just look again at what we're j
| |
| j 9 talking about.
| |
| 1 10 [ Slide 3 ,
| |
| ! 11 That happens to be a Westinghouse loop. The I 12 material that you see in yellow is the primary piping that 'f J
| |
| 13 we're talking about. And here are the eleven breaks.
| |
| I
| |
| % 14 Actually three are branch line breaks that we are talking i 15 about.
| |
| 16 [ Elide.3 17 And these are the break locations that we are saying 18 that for these plants we no longer have to worry about it, 19 either pipe width or jet impingement. Again, the branch lines 20 stay there. The breaks that are associated with the branch
| |
| , 21 lines, and those are terminal end breaks, and they're fairly 22 large. They are larger than the German 10 percent.
| |
| l 23 So again, this is exactly what we're talking about i
| |
| 24 with respect to PWR primary loops. And again, for those 25 plants that have these restraints in there, once the rule is I
| |
| ~e-.,..----..---.-----,.--,-.,-7_-. , - _ . - - . , _ - - - - . _ _ . - . _ . . - ,._-,y-.-- --
| |
| , ~ . , _ - , - _ . - - , . , - . , . -.--e- , - , - - - - . . ~ .
| |
| | |
| i 259 1 in placo, if they havo to romovo the rostraint to do l
| |
| 2 in-service examination, and most of them will have to do these 3 kinds of things, they will then, when the rule is in place, be 4 able to leave the structure out, not have to replace it. And t
| |
| 5 so it has tremendous benefits with respect to ALARA.
| |
| 6 Now heat loss from the pipe, because of these pipe 7 width restraints, is quite large, and.it adds to the 8 environment. There's just so many reasons -- of course, cost i 9 is one that is a positive reason not to have to install these 10 if you're building a new plant.
| |
| 11 Before we get into these two specific applications 12 -- one is Beaver Island; the other is Crystal River --
| |
| 13 MR. SHEWMON: You are finished with the limited rule 14 now?
| |
| 15 MR. BOSNAK: The limited rule -- ,
| |
| 16 MR. SHEWMort : That's what you're going with at this
| |
| , 17 time?
| |
| 18 MR. BOSNAK: The limited rule, I think John said i
| |
| 19 19. We have to evaluate all the comments and then prepare a 20 final rule for the Commission. Roughly, it seems like by the
| |
| , i
| |
| ! 21 end of the year the final rule would go out and become 22 effective within either 30 or 60 days after.
| |
| 23 MR, SHEWMON: Now you're going to change over to 24 these other things, which would not be part of that, which 25 would go beyond it, for our reaction, is that what you're
| |
| ..no - , , - , , . _ , . - - - . , - , , _ , - , - - , - - - - . - - . . - , - . . . - . _ , . , , . - . , , . , . , , . , - _ . , . - , , - .
| |
| | |
| 260 1 starting in on now or not?
| |
| 2 MR. BOSNAK: Not at this time.
| |
| O 3 MR. SHEWMON: I would like to have you make a --
| |
| 4 MR. BOSNAK: I will let you know. Actually we don't 5 plan to get into the broad scope rule, unless you have 6 questions.
| |
| 7 MR. SHEWMON: Okay, fine. Go ahead.
| |
| 8 MR. BOSNAK: Because the broad scope rule still has 9 not been publia hed . We don't even know the final form that 10 it's going to take.
| |
| 11 CS11de.3 12 The next area is arbitrary intermediate breaks. I 13 have listed here for you the plants that are involved. And 14 let me define what an arbitrary intermediate break is.
| |
| 15 First of &ll, in accordance with our current rule, 16 the Standard Review Plan, 361, 362, you must postulate pipe 17 breaks in a system at a terminal end, any terminal end, and at
| |
| ! 18 those locations in which you exceed certain special criteria, 19 or in the case of Class I systems, certain fatigue criteria.
| |
| 20 The only systems in which fatigue is evaluated are Class I.
| |
| 21 That's why the fatigue criteria does not apply for Class II 22 and Class III.
| |
| I 23 Now these values, these specified limits, are in 1
| |
| i l 24 general 80 percent of the normal limits specified in the i
| |
| 25 code. So if you are above that break point, you have to i l
| |
| 1
| |
| - -~ -- - -- - - -
| |
| | |
| 261 1 postulato a broak, and if you don't do a good design on your 2 system, obviously you're going to have more.
| |
| 3 We have well-designed systems in which there are no i 4 locations other thar. the terminal ends, and those are not 5 considered at all. They stay. But there are no intermediate 6 locations that exceed our 80 percent criteria.
| |
| 7 MR. MICHELSON: Are anchor points considered 8 terminal ends?
| |
| 9 MR. BOSNAK: Anchor points are terminal ends.
| |
| 10 So what do you do if you don't have any?
| |
| 11 The rule says arbitrarily select two, and these are 12 the so-called arbitrary intermediate breaks.
| |
| 13 Now we started this in late '84 at Catawba, i
| |
| 14 Catawba-2. Unit 2 was the first plant. Basically, I think we 15 had an Owners Group, but Duke Power was interested in going 16 ahead and proceeding ahead ,of the rest of the plants, and l
| |
| 17 there was interaction with the Staff, about six to eight 18 months, I believe, where we went through and decided which 19 systems, if any, are subject to large dynamio load fatigue for 20 stress corrosion oracking. l 21 Once we ruled those out, then we went ahead and !
| |
| 22 said, for the other systems that these three diseases, if 23 you will, are not present, you may go ahead and eliminate the i
| |
| 24 arbitrary intermediate breaks. This was not an exemption 25 based on fracture mechanics, It was just a deviation, if you l i
| |
| l
| |
| . - - . , _ - - . - .-, . -- . , , - . ~ . - -,
| |
| | |
| 262 1 will, based on tho Standard Review Plan. !
| |
| l l
| |
| 2 Now what kind of tradeoff did we get? We do have f i
| |
| 3 the caveat that any piece of equipment that is there 4 throughout the piping run -- and this is a system that we're 5 talking about from terminal end or anchor to anchor -- all of 6 the equipment has to be qualified for n?n-dynamic effects of a 7 non-mechanistic break with the greatest consequences on the B equipment.
| |
| 9 Now we think what we have there is much better with 10 respect to plant safety than what we had before, applying 11 arbitrarily, if you will, the fact that pipes are going to 12 break at these two locations. And they were, as I tried to 13 explain, selected rather arbitrarily.
| |
| 14 MR. SHEWMON: Would you explain what that last 15 statement means? Be qualified for non-dynamic effects of a 16 non-mechanistic pipe break with the greatest consequences?
| |
| 17 MR. BOSNAX In other words, you don't have to 18 qualify equipment for a jet focusing on it, but you do have to 19 qualify the equipment for static conditions of pressure, 20 temperature, flooding. That's what that means.
| |
| 21 MR. MICHELSON: Resulting from what kind of break?
| |
| 22 Is it still the double-ended rupture?
| |
| l 23 MR. BOSNAX: Whatever you want. Where there are no 24 dynamic effects associated with it.
| |
| 25 MR. MICHELSON: It's not whatever you want; it's
| |
| | |
| 263 1 whatover is required, boccuso it makes quito a difforenco in 2 pressure and temperature as to what you assume. So what do
| |
| \
| |
| 3 you require to be assumed?
| |
| I 4 MR. BOSNAK: Static conditions of the pressure and j 5 temperature of the fluid.
| |
| 6 MR. MICHELSON: I understand that. But you have to 7 have some kind of break in order to get time into this whole 8 thing.
| |
| 9 MR. BOSNAK: We're not getting time in. We're 10 staying away from that.
| |
| 11 MR. MICHELSON: If you've got vent areas, whatever, 12 you've got to put some time limit on this.
| |
| 13 MR. SHEWMON: How high does the water level get 14 before it stops coming?
| |
| 15 MR. BOSNAK: They can look at it. If they do have 16 vent areas, if they do have means for the fluid that escapes, 17 you may take that into account. But again, we are not getting 18 into situations in which we have, in one millisecond, a sudden 19 release of the fuel in the pipe.
| |
| 20 MR. MICHELSON: You understand, of course, some of 21 these transient pressures, which are sufficiently high to 22 cause walls to cave in and whatever, are created in a short 23 time range.
| |
| 24 Are you essentially saying you are eliminating 25 those?
| |
| I
| |
| | |
| F 264 i
| |
| ~
| |
| 1 MR. SHEWMON: Yos.
| |
| 2 MR. BOSNAK: Yes. I 3 MR. SHEWMON: But what the greatest consequences on f f
| |
| r 4 equipment are, I don't know yet. Let me stay with that one. !
| |
| t I
| |
| 5 MR. BOSNAK: You have to look at the location. If i i
| |
| 6 you have a particular item, that's what we're getting at with i I
| |
| 7 t rae greatest consequences. In other words, if you have a !
| |
| i 8 system that goes from here to here (indicating) and an item ;
| |
| 9 over here (indicating), you cannot select your break, if you t
| |
| ; 10 will, here (indicating) It has ;ot to have the greatest }
| |
| i l t
| |
| 11 static --
| |
| l 12 MR. SHEWMON: In other words, you've very little 13 room, not much imagination. Give me an example. ;
| |
| 14 MR. BOSNAK: That was the example I tried to give f f
| |
| 15 you. !
| |
| i L
| |
| 16 MR. SHEWMON: What's the item? )
| |
| t 17 MR. BOSNAK: My item, my motor control center, for .
| |
| 18 instance, is here (indicating) I have a break over there ,
| |
| 19 (indicating;, and that can't affect it. We are saying you .
| |
| f f
| |
| 20 have to look at that location, so that it has the greatest ;
| |
| 21 consequences. [
| |
| t e
| |
| 22 MR. SHJWMON: You don't have to considgr insetiai !
| |
| (
| |
| 23 effects 6 but you have to consider an awful lot of water; $s l 24 that what you mesn by standard? [
| |
| t k
| |
| 25 MR - BOSNAK: That's correct. Flooding. If you do i
| |
| )
| |
| s >
| |
| i I
| |
| i
| |
| | |
| 265 1 havo an egross for the water, you can take that into account.
| |
| l s 2 But if you don't have that sort of situation, it might flood 3 the motor control center.
| |
| 4 MR. MICHELSON: That doesn't help me a lot, though.
| |
| 5 I've got a small, given room, It's got a large pipe in it.
| |
| 6 Depending on how that pipe breaks --
| |
| 7 MR. SHEWMON: Are there any small, given rooms in 8 that system shown there?
| |
| 9 MR. MICHELSON: Inside of containment, there's a lot 10 of compartments.
| |
| 11 MR. SHEWMON: He only showed the primary system 12 between the steam generator --
| |
| 13 MR. BOSNAK: This applies to all high-energy lines.
| |
| 14 We're not talking about -- it's not the primary loop anymore.
| |
| 15 That's why I tried to divorce this from the rest of the -- it 16 has nothing to do with the , basic rule.
| |
| 17 MR. MICHELSON: Inside and outside of containment, 18 as I understand it.
| |
| 19 MR. BOSNAK: That's correct.
| |
| 20 MR. MICHELSON: Back to my question, though.
| |
| 21 Depending upon the rate at which the energy is released from 22 thai pipe determines what the pressure is in the room and so 23 forth. So you said, okay, I'm not going to take shock wave 24 effects of millisecond type breaks.
| |
| 25 What break am I going to take in determining the l , , . . - - - - , , , ,
| |
| | |
| 266 1 prossuro in the room?
| |
| 2 MR. BOSNAK: That is why we tried to get into the 3 non-mechanistic situation.
| |
| 4 MR. MICHELSON: Okay, that's a good word, I guess.
| |
| 5 I don't understand what it means, and that's what I'm trying 6 to find out. What is that non-mechanistic break?
| |
| 7 MR. BOSNAK: It means you don't have to go through a 8 time-history type of analysis.
| |
| 9 MR. MICHELSON: What do you go through?
| |
| 10 MR. BOSNAK: Again, you consider, without any 11 dynamic effects, that you're going to have an opening in that 12 fluid pipe, and it is going to spray, if you will, just 13 distribute the fluid, and its pressure, its temperature, its 14 humidity, meisture.
| |
| 15 MR. MICHELSON: But that temperature is a dynamic i
| |
| 16 effect, because it depends upon the rate of the materials 17 entering the volume and the rate at which it's filling the l 18 volume.
| |
| 19 MR. BOSNAK: Take the temperature and pressure 20 within the fluid line. That's what you use.
| |
| l l
| |
| l 21 MR. MICHELSON: That doesn't count at all. Even 22 simple thermodynamics tells you that's not right. Long ago at 23 TMI, we learned you don't take the condition inside the pipe l
| |
| 24 and think that that's what's in the room.
| |
| l
| |
| ; ["%g 25 MR. SHEWMON: That's an upper bound.
| |
| l
| |
| | |
| 267 l 1 MR. BOSNAK: That's an upper bound, and that's what ,
| |
| 2 we're saying to use. (
| |
| 3 MR. MICHELSON: No superheating, for instance, at j 4 all. t
| |
| [
| |
| 5 MR. BOSNAK: No superheating. l f
| |
| i 6 MR. MICHELSON: Use the temperature of the fluid in i 7 the pipe that breaks.
| |
| 8 Now how do you calculate the pressure? I don't want I i
| |
| 9 to get into details. f i
| |
| 10 MR. BOSNAK: Take the pressure that's in the basic j t
| |
| 11 line. !
| |
| i-12 MR. MICHELSON: That's the pressure in the room? i i
| |
| 13 MR. BOSNAX: That's what you use an upper bound.
| |
| 14 MR. MICHELSON: I hope not. Rooms can't take a f i
| |
| 15 thousand pounds pressure. {
| |
| i 16 MR. BOSNAK: Again, we're not looking at the r
| |
| r 17 structure. We're looking at equipment, equipment [
| |
| 18 qualification. 't I
| |
| 19 MR. MICHELSON: Are you any longer considering the i 20 effects on structures of pipe breaks, other than jet i
| |
| 21 impingement and whipping? Are you eliminating pressurization i
| |
| 22 compartments as a potential problem? !
| |
| i 23 MR. BOSNAK: As far as pressurization compartments i
| |
| l 24 are concerned for these situations, no. Again, the answer is, !
| |
| + 25 you look at the pressure and temperature, and you come up with
| |
| ?
| |
| | |
| 268 1 a sconcrio that demonstratos that what you havo will not +-
| |
| 4 2 MR. MICHELSON: This sounds extremely strange to 3 me. Maybe everybody else understands it; I don't understand 4 it.
| |
| 5 MR. MARK: Do you assume that you have an crifice 6 equal in size to the diameter of the pipe with fluid in that 7 pipe with a temperature and pressure that you know to be 8 there, and that stuff comes out at that rate into the room?
| |
| 9 MR. MICHELSON: That's a good problem. That's the 10 one we have been using.
| |
| 11 MR. BOSNAX: Again, these are areas in which there j 12 were formerly isolated brekks.
| |
| 13 MR SHEWMON: What you want to know is whether or 14 not a piece of presumed electrical or mechanical equipment in 15 this space will continue to function. You assume that there i
| |
| 16 is nret a jet, and thus inertial forces don't come on it, but 17 with regard to temperature or water levels that could come or i
| |
| 18 steam, you do make sure that the equipment can withstand it.
| |
| 19 MR. BOSNAK: You do have to have there 3 20 deterministic model based on what you have on that particular 21 space with respect to egress of fluid as it comes out of the 22 pipe, so that you would, in effect, have an orifice.
| |
| 23 MR. MICHELSON: 'You must postulate a break size of 24 some sort for the purposes of calculating environmental 25 conditions. I don't know how you would ever do it otherwise.
| |
| t
| |
| | |
| 269 1
| |
| i But you said, at first, you didn't do that, and now 2 I think you're coming --
| |
| 3 MR. SHEWMON: He said it doesn't have inertial l 4 effects.
| |
| 5 MR MICHELSON: That I don't have any sweat with.
| |
| 6 MR. SHEWMON: Inertial effects are the or. l y thing 1 you've eliminated.
| |
| 8 MR. BOSNAX: We start with an upper bound 9 situation. If somebody can live with the pressure and 10 temperature of the fluid in the line, fine. That makes it 11 quite simple. If they cannot, then we're into a situation in 12 which you assess what you have.
| |
| 13 Most all of these plants have had breaks in these 14 particular compartments anyway, so that from the point of view 15 of equipment qualification, this is what they are using 16 throughout the run of the system.
| |
| 17 MR. MICHELSON: I think you are beginning now to 18 back off from requiring the users' old original analysis. You l
| |
| 19 san come up with some new justification for lesser 20 qualifications.
| |
| 21 MR. BOSNAK: We're saying, in spaces in which you've 22 never had a break before, you could arbitrarily say, " O k a y .- !
| |
| 23 don't have to qualify my equipment for anything." We are now l
| |
| 24 saying that you do have to have qualification, and it must be h 25 along these lines.
| |
| I l
| |
| | |
| 270 1 MR. EBERSOLE: Would this apply to a 400-pound cold 2 water pipe? [
| |
| 3 MR. BOSNAK: If it was a system in which we didn't f
| |
| 4 have to worry about waterhammer, yes. j 5 MR. EBERSOLE: If it was a system that you did have !
| |
| i 6 to worry about waterhammer, yes, also? !
| |
| i 7 MR. BOSNAK: If it was a system that you did have to ;
| |
| 8 worry about waterhammer, this would not apply. [
| |
| i i
| |
| 9 MR. SHEWMON: Dave, I'm not sure what subcommittee 10 should consider this, but I think at this point we're into ,
| |
| t 11 things which are not a report on something which has been gone j i
| |
| 12 over in the subcommittee, and we have gone through ot> r time, 13 I think we got the main point across, which was a i
| |
| 14 GDC-4 modification. !
| |
| i 15 MR. BOSNAK: This has nothing to do with GDC-4, and i
| |
| 16 that's the main thing you want to keep in mind. It has ;
| |
| 17 nothing to do with GDC-4.
| |
| 18 You asked for us to tell you where we were getting 19 into changing how postulated pipe breaks were considered. {
| |
| 20 This is another category completely separate from GDC-4.
| |
| 21 MR. SHEWMON: Nobody's equipment qualification, is ,
| |
| 22 that right, conditions under which you must qualify equipment; [
| |
| 23 is that the question that. arises here?
| |
| 24 MR. BOSNAK: That seems to be one of the questions !
| |
| 25 that's being asked. i
| |
| | |
| 271 1 MR. MICHELSON: Another question is the operability, 2 say, of valves under dynamic conditions. This eliminates the
| |
| ' O 3 dynsmic conditions that the valve ever sees. We've got to
| |
| * 4 think about, do we want to eliminate dynamic requirements on i 5 valves? If we do, fine. But we really have to give it, you 6 know, some careful thought.
| |
| 7 MR. BOSNAX: Which dynamic conditions are you t
| |
| 8 referring to?
| |
| P 9 MR. MICHELSON: If you break a pipe downstream of i
| |
| 10 the valve that's to isolate the break, do we still include }
| |
| 11 that kind of a break in the qualification of a valve?
| |
| 12 MR. BOSNAX: You still have somewhere in that system t
| |
| 13 a break. It's a terminal end break. t s i
| |
| )
| |
| 14 MR. MICHELSON: But you really are fuzzy on it. You i
| |
| i 15 said we will have a break for the purposes of determining ;
| |
| 16 environment. You haven't said we'll have a break for the 17 purposes of determining dynamic operating conditions in the i t
| |
| i 18 qualifications of that equipment.
| |
| 19 MR. BOSNAK: If that break is one of those that it
| |
| ]
| |
| 20 has eliminated, you don't have it any longer, i
| |
| 21 MR. MICHELSON: That's right. And I think you're 22 eliminating those breaks. T l
| |
| 23 MR. EBERSOLE: A clarification, please, on the first 24 two bullets. It's ambiguous. Breaks postulated at terminal f i
| |
| 25 end and at intermediate locations, and there you qualify it i
| |
| i :
| |
| ! I
| |
| | |
| 272 1 with stress or usage factors --
| |
| : r. 2 MR. BOSNAK: That's today's requirement. That O 3 should not be ambiguous. That's what's on the books today.
| |
| 4 MR. EBERSOLE: So that's where you have a fatigue 5 factor in both locations, the ends or in the middle.
| |
| 6 MR. BOSNAK: Forget the ends. The ends are not 7 changing at all. Usually you will have a fatigue factor 8 there. Usually that's where the fatigue factor is higher. So 9 we're not changing that at all 10 MR. EBERSOLE: So you still get the ends.
| |
| 11 MR. BOSNAK: You always get the terminal ends, 12 anchors.
| |
| 13 MR. EBERSOLE: They'll get a full-size break, and O 14 you have to deal with thermodynamics.
| |
| 15 MR. BOSNAK: Exactly. That doesn't change.
| |
| 16 MR. EBERSOLE: That means, for instance, main 17 feedwater will have to be considered to break upstream of the 18 swing checks, and you must deal with the hypothetical break i 19 like that and have the flapper valves be defended against 20 impact loads on reverse flow of the boiler pipe.
| |
| 21 MR. BOSNAK: That's correct. That's not going to 22 change.
| |
| 23 MR. EBERSOLE: By the way, that hasn't been very 24 well done.
| |
| 25 MR BOSNAK: I know. I agree.
| |
| | |
| 273 1 If we do havo the timo, I would like to get into 2 these two other plants, because we would like to get the O 3 committee's input on Crystal River and also Beaver Valley, if 4 that's possible.
| |
| 5 MR. MICHELSON: Clarify where on your chart did you 6 tell us that we'still have the terminal end breaks, because 7 that statement we were dealing with didn't seem to say that.
| |
| 8 MR. BOSNAK: It says " postulated at terminal ends 9 and at intermediate locations." I'm saying here, in 10 well-designed systems, there are no intermediate, but there 11 are always terminal ends.
| |
| 12 MR. MICHELSON: I read this statement, the third 13 from the bottom, it says "all equipment throughout piping run 14 is qualified." I read that as meaning that throughout piping 15 run, there are none --
| |
| 16 MR. BOSNAK: If you have a break and if you're in a 17 terminal end location, + hat is still there. We haven't 18 changed that. %e haven't changed any of the effects.
| |
| 19 MR. WARD: Bob, let me interrupt a minute. I think 20 the committee -- there is enough concern about this that we 21 are going to want to hear more about it. I think you have to l
| |
| ; 22 get clarified enough on what the issues of concern are to 23 figure out which subcommittee should take a look at it, but I 24 think we are going to want to hear more.
| |
| 25 Why don't you go on? Were you going to talk about
| |
| | |
| 274 1 the Crystal River and Boavor Valloy?
| |
| l
| |
| ~x 2 MR. BOSNAX: I would like to.
| |
| 3 MR. WARD: Why don't you move on to that. Just 4 recognize that we probably haven't closed out with you on the !
| |
| l 5 intermediate break issue. !
| |
| i 6 [ Slide.] ;
| |
| i 7 MR. BOSNAX: I want to make it clear here, these are ;
| |
| i 8 preliminary proposals that we have.
| |
| i r
| |
| 9 Now with respect to Crystal River, they have now i
| |
| ?
| |
| 10 installed 32, and they are between 1000 and 2000 kip snubbers I f
| |
| 11 on the reactor coolant pump. They have had B&W look at a -- I t
| |
| l 12 call it, if you will, an optimization study, an analytical i i
| |
| 13 study to see what they could do. f 14 These large snubbers cannot be tested. They are f i
| |
| 15 .rather unreliable with respect to their construction, the 16 ability to come in periodically and do the kind of testing l 17 that snubbers require. So what they are proposing is to i
| |
| n 18 rearrange the system, if you will -- and this is a question I 19 that Dr. Siess raised earlier -- since the LOCA loads are, in f i
| |
| 20 effect, going away, what would you all think about putting in 21 eight smaller snubbers? Again, they're talking about 400 kip, 22 much smaller than the two million pound snubbers, and
| |
| [
| |
| 23 tentatively four rigid restraints. i I
| |
| 24 Again, the benefits are as you see them here. The !
| |
| {''
| |
| x 25 margins obviously are going to be revised.
| |
| f
| |
| +
| |
| l
| |
| | |
| 275 l
| |
| 1 In your letter of Juno of '83, you montioned the 1 1
| |
| 2 fact that we want to be sure that we have reliability of the l 3 primary loop, the supports for the primary loop. The margins 4 will not be what they are today. In some cases, they are 5 going to increase, but in most cases, they are probably 6 somewhat less.
| |
| 7 Now we believe this will make a more reliable 8 system. Again, we have only had a tentative look-see, but 9 from what we have seen so far, we believe that it represents a 10 benefit, a positive way to go with respect to the primary loop 11 on this particular plant.
| |
| 12 Now once we do this for one plant, obviously others 13 will probably be interested in doing it, because in the
| |
| ) 14 primary loop, again because of these tremendously large pipe 15 break loads, we do have extremely large snubbers. So this 16 represents, I would call i t, forward thinking.
| |
| 17 We would like to have the benefit of the committee's i 18 thoughts with respect to a proposal such as this.
| |
| 19 MR. OKRENT: What is the inspectability of the welds 20 joining piping to the pump? Is it good from both sides?
| |
| 21 MR. BOSNAK: For this particular plant, I can't :
| |
| 22 answer that question. It's one of the things we want to be 23 looking at.
| |
| 24 MR. OKRENT: Do you want to get an opinion today
| |
| /~} 25 from the committee? I don't understand what --
| |
| i
| |
| | |
| 276 ;
| |
| 1 MR. COSNAK: We want to know how you fool about l
| |
| 2 trying to go back in, given the fact that we have leak before 3 break, and the large dynamic loads for the primary loop are no l f
| |
| 4 longer present. Should we -- or is there any objection to 5 going in and looking at this to see if we can improve the t
| |
| i 6 system reliability? t 7 MR. REED: This is a removal operation of the 32, or f
| |
| 8 are they not installed?
| |
| 9 MR. BOSNAK: These are all there. Currently there i t
| |
| 10 are -- and I have somewhere in here in their submission the [
| |
| I 11 exact size -- but there are 323 snubbers, and they are between [
| |
| +
| |
| 12 1000 and 2000 kips. They are large snubbers. They are only [
| |
| : 13 there for the reactor coolant pump. f t
| |
| s 14 MR. REED: I can certainly see many improvements ;
| |
| i 15 from their removal j 16 MR. OKRENT: I would suggest that as part of your [
| |
| f 17 review, if you review this, that you make an effort to find [
| |
| i
| |
| }
| |
| 18 out why the British are not buying leak before break and 19 whether -- and I don't know; I don't recall --
| |
| 20 MR. BOSNAK: The last encounter, I'think, we had [
| |
| I L
| |
| 21 with the British was that they were still considering it.
| |
| 22 They have gone ahead with decoupling of LOCA and SSE, but i I
| |
| 23 they are still considering it, and it may be a political 24 situation, as mentioned here earlier, f 25 MR. WARL: You know, the whole comparison of our i
| |
| s
| |
| | |
| . . - _ _. =. .
| |
| 277 1 practico and foreign practico, I guess bothorod me a little
| |
| _ 2 bit. Perhaps you are moving out into a leadership role and 3 made changes, which is fine. But on the other hand, the 4 British, despite maybe their LWR program is rather abstract, I i 5 didn't think O' Brian gave us a very satisfactory answer when 6 Okrent askea him what the British thinking was.
| |
| 7 If they do have some thought-out --
| |
| 8 MR. BOSNAK: We will attempt to get, as best we can, 9 the latest, up-to-date input from them.
| |
| 10 MR. OKEENT: You might try talking to Mr. Curry.
| |
| 11 MR. WARD: The Germans have gone a long way in this i 12 direction, but they are making some rather substantial changes i
| |
| 13 in the piping quality. Or are they really substantial? Are
| |
| ~14 they just apparent?
| |
| j 15 MR. SHEWMON: They are changing stresses.
| |
| 16 MR. BOSNAK: They are changing their techniques.
| |
| 17 They are trying to use forged components. They are 18 eliminating, wherever they can, weldments. I think all of the 19 new plants around the world are trying to do that.
| |
| 20 MR. SHEWMON: I suggest we close at this point.
| |
| 21 MR. BOSNAK: If I can get into Beaver Valley, just 22 to give you a quick idea of where they stand.
| |
| 23 MR. SHEWMON: You aren't going to get a decision 24 here.
| |
| 25 MR. BOSNAX: We're not looking for that. I l _ _ _ _ . _ _ _ _ . ._ - _ . . - . _ . _ _ _ _
| |
| | |
| 278 i undorstand they are going to come in in September, lator this 2 month, to talk to the subcommittee. But they are looking at 3 the balance-of-plant systems and trying to see in which 4 systems can they say they're going to have leak before break 5 performance and in which systems can they again remove these 6 dynamic restraints, pipe whip :estraints, jet impingement 7 barriers. That is what they are proposing.
| |
| 8 It is an innovative approach. They want to study 9 all of the systems for stress corrosion fatigue and large 10 dynamic loads.
| |
| 11 Our legal friends tell us that they believe they 12 would need the broad scope rule in place before they could got 13 ahead with this thing, but that is just a-legal opinion.
| |
| i 14 [Whereupon, at 5:45 o' clock, p.m., the transcribed 15 portion of the meeting was concluded.3 16 17 18 19 20
| |
| [ 21 l
| |
| 22 4
| |
| 23 24 25 l
| |
| i l
| |
| \
| |
| | |
| 1 CERTIFICATE OF OFFIC1AL REPORTER 2
| |
| 3 4
| |
| 5 This is to certify that the attached proceedings t1 before the United States Nuclear Regulatory Commission in the 7 matter of* ADVISORY COMMITTEE ON REACTOR SAFEGUARDS 8-9 Name of Proceeding: 305th General Meeting 10 11 Docket No.
| |
| 12 P1 ace: Washington, D. C.
| |
| 13 Date: Thursday, September 12, 1985
| |
| .i
| |
| , 14 i
| |
| 15 were held as herein appears and that this is the original I 16 transcript thereof for the file of the United States Nuclear 17 ReguIatory Commission, 18 .
| |
| ] '[
| |
| (Signature) ..j, , g /Q [{
| |
| (Typed Name of Reporter) Mimie Meldzer 20 21
| |
| 'l 1 22 1
| |
| 4 A 23 Ann Riley & Associates, Ltd.
| |
| i 24 25
| |
| | |
| 30STN ACRS EETING SEPTEPEER 12,1985 l GESSAR II 10:45 AM to 3:15 PM [ includes Lunch Break, tentatively set at 12:30 to 1:30 PM]
| |
| ... Presenter Time in Min.
| |
| : 1. DefinitionofFDA NRC 20
| |
| : 2. Major Results and Conclusions from PRA; NRC 30 Qualifications concerning PRA Staff Estimates of Mean core melt frequency' E 10
| |
| : 3. Existing Quantitative Interface Requirements NRC 15 on Performance, Reliability, etc. including seismic E 10
| |
| : 4. Safety Goals for Future Plants NRC 10-15 Containment Requirements for Future plants
| |
| : 5. Containment failure likelihood and t. ode, NRC 10 given core melt thru vessel
| |
| : 6. Hydrogen control: Why not seismic NRC 10 requirements on ignitors?
| |
| : 7. USIs and GSIs A Why cyclone pump? E 5 Why rely on UPPS with no detailed NRC 5 analysis?
| |
| : 8. Problem in staff review of flooding PRA NRC 10
| |
| : 9. Status of Containment Venting Desigi1" E 10 1.0 . Status of UPPS? Seismic, other features E 20-25 Can it work if there is a large fire?
| |
| Should it be a much better system? Bunkered?
| |
| : 11. Review of adverse effects due to failures of NRC 10 spurious actuations caused by an earthquake;< ,Not analyzed
| |
| , by GE or NRC g 10 Fires caused by an earthquake s I
| |
| : 12. Other 15 i
| |
| l . l
| |
| | |
| Agenda for ACRS Meeting on September 12, 1985 8:45 a.m.
| |
| i Room 1046, H Street RECENT SIGNIFICANT EVENTS Date Plant Presenter / Office Event telephone g
| |
| (
| |
| 9/4/85 Hope Creek ~
| |
| Inadvertent Actuation of Fire J. Henderson, IE 2 Suppression System 492-9654 7/21/85 Turkey Pt. 3 Post Trip Loss of Auxiliary i
| |
| J. Henderson, IE ' 3 Feedwater 492-9654 7/23/85 Turkey Pt. Potential MSIV Failure At V. Hodge, IE 4 Low Steam Flow 492-7275
| |
| ~
| |
| 8/7/85 Maine Yankee Common Mode Problems with Steam 9/3/85 J. T. Beard, NRR 9 Generator Pressure Indication 492-7465 8/28/85 Peach' Bottom New Pipe Crack Indications G. Gears, NRR y 13 ;
| |
| 492-8362 7/2/85
| |
| * Fermi 2 Premature Criticality N. Chrissotimos 15 '
| |
| RIII 312-790-5716 ,
| |
| *no formal presentation
| |
| +
| |
| s t
| |
| O ;
| |
| i
| |
| | |
| . HOPE CREEK CO2 RELEASE O 9'a'8s J. B. HENDERSON, IE-EGCB RELEASE OCCURRED ABOUT 8:45 AM
| |
| . A SITE EMERGENCY RESPONSE DRILL WAS IN PROGRESS
| |
| /
| |
| CO2 RELEASED FROM STORAGE TANK f0 PROTECTED VOLUME THROUGH '
| |
| NORMAL PIPING SYSTEM PROTECTED VOLUME, FUEL TANK ROOM UNDER DIESEL-GENERATOR C02 ESCAPED TO OTHER PARTS OF BUILDING COMPLEX PERSONNEL EVACUATED FROM BullDING COMPLEX NO APPARENT DAMAGE TO STRUCTURES, SYSTEMS.0R COMPONENTS
| |
| ' COMPLICATION - MOST THOUGHT THIS PART OF SCENARIO, NOT REAL 23 PERSONNEL TRANSPORTED TO HOSPITAL INADVERTENT ACTUATION SIGNAL PROGRAMMED DISCHARGE 2 TONS ,
| |
| ; ACTUAL - 10 TONS l LICENSEE BELIEVES PROBLEM MAY BE IN CONTROL PANEL l
| |
| PANEL SENT TO MFR (CARD 0X) FOR EVALUATION ACRS MEETING 9/12/85 2.
| |
| | |
| TURKEY POINT 3 POST-TRIP LOSS OF AFW JULY 21, 1985 (J. B. HENDERSON, IE) t
| |
| - PROBLEM - ALL THREE TUR'BINE-DRIVEN AFW PUMPS BECAME INOPERABLE
| |
| / ''
| |
| DURING POST-TRIP RECOVERY PERIOD.
| |
| I SAFETY SIGNIFICANCE - IMPAIRMENT OF DECAY HEAT REMOVAL
| |
| /
| |
| CAPABILITY. .
| |
| - BRIEFING SIGNIFICANCE - THE ONLY SITE OTHER THAN DAVIS-BESSE WITH NO ELECTRIC DRIVE AFW PUMPS.
| |
| - TWO TURBINES TRIPPED TO LdCK OUT ON MECHANICAL OVERSPEED TRIP.
| |
| () FLOW CONTROL VALVE ON THIRD UNIT FAILED.
| |
| LICENSEE CORRECTIVE ACTION - 1. RETRAINING ON TURBINE GOVER-NOR RESET. 2. PERFORM OVERDUE MAINTENANCE ON AIR SUPPLY SYSTEM TO CONTROL VALVE. ,
| |
| l i -
| |
| OVERSPEED TRIP PROBLEM MAY BE GENERIC TO A SIZEABLE CLASS OF
| |
| ~
| |
| TURBINES :
| |
| ! - NRC FOLLOWUP - NOT DEFINED YET i
| |
| i 1 .
| |
| I
| |
| | |
| i O >
| |
| I POTENTIAL MSIV FAILURE AT LOW STEAM FLOW
| |
| ! TURKEY PT. 3, 4 i JULY 23, 1985
| |
| ~
| |
| .e BY VERN H0DGE, IE i , TWO ISSUES:
| |
| i 1.
| |
| i -
| |
| UNANALYZED CONDITION FOR MSLB ACCIDENT.
| |
| : 2. INADEQUATE TESTING PRACTICE ,
| |
| 1 i
| |
| .i 1
| |
| 1 !
| |
| 1 i
| |
| j l
| |
| 1 ,
| |
| i O ,
| |
| I k !
| |
| I
| |
| * * '- - " - W= e*-- **
| |
| | |
| UNANALYZED CONDITION FOR MSLBA
| |
| : O
| |
| : 1. MSIVs WON'T CLOSE I t
| |
| A. WITHOUT STEAM FLOW .
| |
| B. WITHOUT INSTRUMENT AIR ACTUATOR POWER i
| |
| , c. ACCUMULATORS ARE T00 SMALL
| |
| : 2. ' PROBLEM APPLIE'S TO TURKEY POINT AND ROBINSON
| |
| : 3. THRESHOLD STEAM FLOW NOT KNOWN <
| |
| ASSUMED TO EXCEED AFW CAPABILITY CONTINUED BLOWDOWN POSSIBLE O .
| |
| e O
| |
| 5
| |
| | |
| JUSTIFICATION FOR CONTINUED OPERATION
| |
| () ASSURE SUFFICIENT INSTRUMENT AIR:
| |
| 1.
| |
| DIESEL AIR COMPRESSOR BACKS UP PLANT SYSTEM
| |
| : 2. FOSSIL PLANT SYSTEMS TIED IN FOR BACKUP -
| |
| J 3.
| |
| PLANT SHUTDOWN ON FAILED INSTRUMENT AIR SUPPLY CORRECTIVE ACTION EXPEDITED DESIGN MODIFICATION T0:
| |
| 1.
| |
| ["') ASSURE MSIV CLOSURE IN 5 SEC W/0 STEAM ASSISTANC 2.
| |
| ALLOW TESTING MSIV CLOSURE W/ SECURED ELECTRIC INSTRUMENT AIR ACTUATOR POWER
| |
| (
| |
| k i
| |
| e k
| |
| 1 i i
| |
| l
| |
| | |
| l INADEQUATE TESTING PRACTICE )
| |
| O MSIVs STROKE TESTED WITH INSTRUMENT AIR CONNECTED TURKEY PT, ROBINSON CITED IN FEBRUARY 1985 TO VIOLATE -
| |
| 10 CFR 50.55A(G):
| |
| IST OF SAFETY RELATED PUMPS AND VALVES MUST COMPLY WITH ASME BPV, SECTION XI /
| |
| l FAIL SAFE VALVES MUST BE TESTED BY LOSS OF ACTUATOR -
| |
| POWER (PARA. IWV-3415)
| |
| ~
| |
| ACTUATOR POWER INCLUDES BOTH ELECTRIC POWER AND INSTRUMENT AIR POWER O
| |
| NRC RESPONSE AN INFORMATION NOTICE IS BEING PREPARED e
| |
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| |
| | |
| MAINE YANKEE: TWO COMMON MODE PROBLEMS WITH STEAM GENERATOR INSTRUMENTATION (J.T. BEARD)
| |
| | |
| ==SUMMARY==
| |
| | |
| AUG 7, 1985: PLANT AT 78% POWER (EOC), FOUND ROOT VALVES "NOT FULLY OPEN" FOR 9 0F 12 PRESSURE TRANSMITTERS. -
| |
| SEPT. 3, 1985: REFUELING OUTAGE TESTING REVEALED THE "A" ..-
| |
| PRESSURE CHANNEL FOR EACH STEAM GENERATOR WOULD NOT TRIP---
| |
| DESIGN MODIFICATION ERROR---GROUNDING.
| |
| ~
| |
| SIGNIFICANCE: PRE'SSURE INSTRUMENTATION WOULD NOT HAVE
| |
| () RESPONDED PROPERLY TO STEAM LINE BREAK ACCIDENT; BOTH DIVERSE CONDIT. IONS EXISTED FOR WHOLE OPERATING CYCLE,
| |
| . INSTRUMENTATION (E.G., S/G LEVEL) WOULD HAVE ACTUATED, LATER.
| |
| ROOT VALVE PROBLEM "D" PRESSURE CHANNEL ON S/G #1 NOTICED TO BE " SAGGING";
| |
| ; FOUND 3 VALVES FULLY CLOSED (BUT LEAKING), 6' VALVES -
| |
| " PARTIALLY OPEN "
| |
| r VALVES WERE CLOSED FOR HYDRO-TEST; SPRING, 1984,
| |
| | |
| i ,
| |
| i i
| |
| i l
| |
| i i
| |
| i Root VALVG PKo5 L.Ch .
| |
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| |
| | |
| . I INSTR. ROOT VALVES NOT'ON ANY CHECKLIST. LICENSEE l ASSUMPTION WAS: "lF INSTRUMENT INDICATES, VALVES MUST BE OKAY." LEAKAGE CAUSED SATISFACTION STEADY-STATE l INDICATIONS. SLOW TRANSIENT RESPONSES (UP TO 60 SECONDS).
| |
| DESIGN PROBLEM EACH S/G PRESSURE CHANNEL " AUCTIONEERS-LOW" SIGNALS FROM .
| |
| TRANSMITTER LOOPS FROM ALL THREE S/G'S, MODIFICATION MADE TO TAP OFF ANOTHER SIGNAL FROM EACH LOOP TO PROVIDE INPUTS i
| |
| TO.SUB.-COOLING METERS.
| |
| DEFICIENCY IN DESIGN OF MODIFICATION---ANOTHER SIGNAL COMMON ESTABLISHED WITHOUT CHECKING COMMON IN EXISTING CIRCUIT FOR RPS.
| |
| DESIGN REVIEWS FAILED TO FIND ERROR; MOD. INSTALLED AFTER 18-MONTH SURVEILLANCE TESTJ NOPOST-MODIFICATiONTESTING 0F RPS. UNDETECTED FOR ENTIRE OPERATING CYCLE.
| |
| O l H
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| |
| l g j k . g .i h v
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| : 4. k ut
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| - . . uk eT l
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| l w 4 Wv
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| * w :
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| el he A E 4 M
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| . ._q ._ . . . . . . . . - . _ . . _ _ . . . . g
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| . . . . . . . . . 4 f
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| _. . g . .. . . .. .
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| l 2_
| |
| D r
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| | |
| 1 PEACH BOTTOM UNIT 3 - NEW PIPE CRACK INDICATIONS AUGUST 19. 1985 (G. GEARS, NRR)
| |
| PROBLEM - REINSPECTION'0F UNIT 3 RECIRCULATION AND RHR LINES FOR IGSCC (GENERIC LETTER 84-11) REVEALED NEW INDICATIONS. ,-
| |
| /
| |
| NUMEROUS CRACKS INDICATED BY NEW GE " SMART" UT SYSTEM.
| |
| MANY CRACKS DISCOVERED ON WELDS WHICH HAD NO INDICATIONS .
| |
| ~
| |
| UNDER PREVIOUS INSPECTIONS (1983, IEB 83-02).
| |
| ONE CRACK WAS CALLED AT 360*, 35-55% THRU-WALL.
| |
| ~
| |
| O
| |
| * S_!_GNIFICANCE - HIGH PROBABILITY CRACKS WERE " MISSED" UNDER EARLIER INSPECTION PROGRAMS.
| |
| - THESE FINDINGS CONFIRM RECENT TESTS RESULTS ON CUT-0UT WELDS (1.E., CRACKS HAVE BEEN
| |
| " MISSED").
| |
| - QUESTIONS NOW RAISED ON QUALITY OF REINSPECTIONS. '
| |
| BWROG BEING ASKED TO ADDRESS THESE ISSUES IN A SEPTEMBEP. 20, 1985 MEETING WITH NRR.
| |
| 13
| |
| | |
| PEACH BO'll'OM i i No . .,
| |
| pd ULTRASONIC TECilN COMPARISON
| |
| ()
| |
| GENERAL ELECTRIC- SOUTilWEST RESEARC11 ,
| |
| No specific IGSCC detection''or PERSONNEL: No specific IGSCC detection or PERSONNE1:
| |
| sizing training. Only procedure demon- sizing training. Only procedure demon-
| |
| !1 stration by representative personnel re . stration by representative personnel re-lg quired by 1.E. Bulletin 82-03. quired by 1.E. Bulletin 82-03, 8
| |
| All examinations performed EQUIPMENT: All examinations performed EQUIPMENT:
| |
| 3 manually utilizing 1.5 MHZ transducers, manually utilizing 1.5 MHZ transducers.
| |
| No sophisticated sizing transducers No sophisticated sizing transducers available for indication discrimination available for indication discrimination or sizing, or sizing. ,
| |
| All Level IIand III personnel PERSONNEL: All Level 11 and 111 personnel PERSONNEL:
| |
| :1 are EPRI trained and certified in the are EPRI tralned and certifled in the All Level I per- detection of IGSCC. All Level I per-g detection of IGSCC.
| |
| sonnel are trained to the level of their sonnel are trained to the level of their
| |
| ' All personnel involvement ,in exams. All personnel involvement in exams.
| |
| utilized for sizing of. indications are utilized for sizing of indications are 5
| |
| EPRI tralned and certifled in planar EPRI trained and certified in planar flow sizing.
| |
| - flaw sizing.
| |
| All exams are performed with EQUIPMENT: All exams performed manually EQUIPMENT:
| |
| 2.25 MHZ transducers. Where configu- utilizing 1.5 MHZ transducers. All sus-rations permit, the exams were performed oected indications are scanned utilizing with the " SMART" automatic system. All the "SLIC-40" transducer for discrimination '
| |
| questionable Indications are scanned and subsequent sizing..
| |
| s
| |
| -4 utilizing sizing transducers such as "SLIC-40", "WSY-70", OR "RTD" to aid in determining indication origin. __
| |
| | |
| FERMI 2 PREMATURE CRITICALITY EVENT
| |
| (- JULY 2, 1985 (N. CHRIS50 TIM 05, RIII)
| |
| * Problem - Reactor brought critical prematurely
| |
| * Safety Significance - Sqfety limits not violated procedure violation
| |
| * Low power license issued 3/20/85
| |
| * Initial Criticality on 6/21/85
| |
| * Reactor being restarted in source range following a scram
| |
| * Operator pulled eleven rods in group 3, one at a time, from notch 00 (full in) to notch 48 (full out). Pull sheet called for pulling group 3 rods from 00 to 04 as first increment. ,
| |
| * Root cause was operator failure to follow procedure.
| |
| Contributing causes were failure to:
| |
| -- Adequately manage control room
| |
| -- Training vs. procedures
| |
| -- Use hardware (RWM) to fullest potentici
| |
| * Subsequent NRC Actions
| |
| -- Informed of event on 7/15/85 (after full power license issued)
| |
| -- CAL issued by RIII on 7/16/85
| |
| * Status of Resolution
| |
| -- DECO response to RIII CAL
| |
| , -- Augmented inspections
| |
| -- Restricted to 5% by CAL -
| |
| i O
| |
| l
| |
| | |
| What is an FDA f, what does it cover?
| |
| The GESSAR II FDA is issued pursuent to Appendix 0 to 10 CFR Part 50.
| |
| The review covers the technical inforrnation required by the appropriate sectionsof50.34(b). The FDA docurrents the staff's and the ACRS's review of the sub.iect design and is to be utilized by and relied upon by the staff and the ACRS in their reviev of any individual facility license application which references the design. An FDA does not constitute a commitment to issue a permit or license.
| |
| The details and descriptions of the design that have been reviewed by the Sta#f and the ACRS are presented in GESSAR II, its amendments (which are identified in the application) and the SER and its supplements. The SERs and the FDA identify the status of the application and approval.
| |
| O Chances to the design following the issuance of the FDA can only be approved through the process of amending the FDA.
| |
| p 9
| |
| l O
| |
| : O I l
| |
| ! l
| |
| )
| |
| i, i
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| : l
| |
| ! i
| |
| . I i
| |
| A PRESENTATION TO ACRS COMMITTEE l ON GESSAR II i
| |
| J i
| |
| lO '
| |
| 4
| |
| ) WASHINGTON, D.C l
| |
| i
| |
| [
| |
| , GENERAL ELECTRIC COMPANY l SEPTEMBER 12, 1985 i
| |
| i .
| |
| ! I
| |
| ?
| |
| l O ;
| |
| c i l
| |
| | |
| GESSAR II I
| |
| o CONSEQUENCES AND RISK FROM INTERNAL EVENTS l 0 CORE DAMAGE FREQUENCY: 4.3 X 10-6/ REACTOR YEAR
| |
| , o RISK: 1.7 X 10-5 LATENT FATALITIES / REACTOR YEAR i
| |
| j o AREAS MOST CRITICAL TO INTERNAL EVENT CONSEQUENCES 1
| |
| o GES'iriR RISK RELATIVELY INSENSITIVE (< FACTOR OF TW0)
| |
| O To:
| |
| i CORE.HEATUP/ HYDR 0 GEN GENERATION PRIMARY SYSTEM RETENTION EARLY RPV FAILURE CONCRETE COMPOSITION 4
| |
| I o GESSAR RISK MODERATELY SENSITIVE (FACTOR OF 2-5) T0:
| |
| i ,
| |
| i l LATE TELLURIUM RELEASE !
| |
| l -
| |
| HIGH POPULATION SITE !
| |
| SUPPRESSION POOL SCRUBBING I O
| |
| i i l ;
| |
| l l DAH - 1 !
| |
| 9/12/85 . . - . _ - .,
| |
| t
| |
| | |
| o
| |
| ()
| |
| GESSAR II o CONSEQUENCES AND RISK FROM EXTERNAL' EVENTS
| |
| ;. INITIATOR CORE DAMAGE FREQUENCY RISK
| |
| ! SEISMIC 4 X 10-7 9 X 10-7 FIRE 7.5 X 10-8 2.6 X 10-7
| |
| ! FLOOD 6.4 X 10-9 1.7 X 10-8 4
| |
| O
| |
| ) o AREAS MOST CRITICAL TO SEISMIC EVENT CONSEQUENCES .
| |
| i 1
| |
| o SEISMIC HAZARD CURVE
| |
| ; o POOL BYPASS P0TENTIAL STRUCTURAL BUILDING FAILURES CAUSING PIPE BREAKS ISOLATION VALVE RELIABILITY DRYWELL FAILURE 3
| |
| O I
| |
| DAH - 2 l . . - . -
| |
| 9/12/85
| |
| | |
| ._ . _ .=_-. . - - --. . _ - - _ . - - - .- - - . .-.
| |
| 1 O
| |
| MAJOR UNCERTAINTIES IN INTERNAL AND EXTERNAL EVENTS i
| |
| o SEISMIC HAZARD CURVE i o COMPONENT AND STRUCTURAL FRAGILITIES j
| |
| jQ o PARTICLE SIZE DISTRIBUTION i
| |
| j o HUMAN ERROR -
| |
| 1 I
| |
| I
| |
| )
| |
| l O l l
| |
| l l
| |
| 278h
| |
| | |
| o s,n ,
| |
| C n N LJ V (s .
| |
| .1 .
| |
| ..eeting No. Agenda item Handout No.
| |
| 305 -
| |
| 7.2 1 - Addendum Tit 1e ANTICIPATED ACRS ACTIVITIES - 306TH ACRS MEETING, OCTOBER 12-14, 1985 Authors R. F. Fraley Liot of Documents Attached q
| |
| Memo, Browning, Director Division of Waste Mgt. to R. F. Fraley dtd. 9/11/85 k ,g NRC STAFF VIEW ON IMPLEMENTATION OF THE EPA HLW STANDARDS (refers to Item 12 in Handout 1)
| |
| ( I Instructions to Preparer From Staff Person
| |
| : 1. Punch holes R. F. Fraley
| |
| : 2. Paginate attachments
| |
| : 3. Place copy in file box
| |
| | |
| l
| |
| / UNITED STATES o[n NUCLEAR REGULATORY COMMISSION
| |
| ! WASHINGTON, D. C. 20655
| |
| { .
| |
| l I Q* % ....* /
| |
| g g
| |
| ~
| |
| 91135 i arr., n .
| |
| .a R. F. Fraley, Executive Director "N
| |
| MEMORANDUM FOR:
| |
| [ Advisory Committee on Reactor Safeguards @jpg FROM: Robert E. Browning, Director Division of Waste Management A
| |
| | |
| ==SUBJECT:==
| |
| NRC STAFF VIEWS ON IMPLEMENTATION OF THE EPA HLW STANDARDS Your memorandum of July 29, 1985 to William J. Dircks forwarded the ACRS coments on the EPA standards for disposal of high-level radioactive wastes.
| |
| I would like to provide you with additional information regarding the staff's ,
| |
| views on EPA's standards and on implementation of those standards by the NRC.
| |
| The ACRS's concerns are capsulized in the following paragraph from David A.
| |
| Ward's July 17, 1985 memorandum to Chairman Palladino:
| |
| It is our understanding that the NRC Staff has concurred with the proposed EPA standards, including the use of a probabilistic approach on radionuclide release limits. In view of the importance of the ability of the NRC to determine compliance with the EPA standards in licensing a high-level waste repository, we recomend that the Comission assure
| |
| (
| |
| itself that the NRC Staff is correct in endorsing this approach. We believe that demonstration of such compliance will be extremely difficult and that the proposed standards are unduly restrictive.
| |
| The NRC staff recognizes that use of numerical probabilities by EPA represents a novel approach for setting environmental standards. NRC coments on the proposed standards stated "The numerical probabilities in (the proposed standards) would require a degree of precision which is unlikely to be achievable in evaluating a real waste disposal system." In discussions following publication of the proposed standards, the NRC staff explained to EPA the difficulties foreseen in trying to implement a standard containing numerical probabilities. As a result of these discussions, EPA has added a new paragraph to Section 191.13 of the standards which reads as follows:
| |
| " Performance assessmnts need not provide complete assurance that the requirements of 191.13(a) will be met. Because of the long time period involved and the nature of the events and processes of interest, there will inevitably be substantial uncertainties in projecting disposal .
| |
| l system perfonnance. Proof of the future perfonnance of a disposal system 1s not to be had in the ordinary sense of the word in situations that i
| |
| | |
| u D -
| |
| y
| |
| ..)
| |
| deal with much shorter time frames. Instead, what is required is a reasonable expectation, on the basis of the record before the implementing agency, that compliance with 191.13(a) will be a:hieved."
| |
| The staff considers that this wording (which conforms closely to 560.101(a)(2) of the Comission's regulations) sets reasonable bounds on the degree of assurance required for estimates of the likelihood and consequences of potentially disruptive events and processes. The Commission will not need to place sole reliance on probabilistic analyses when evaluating repository safety but, rather, will have considerable opportunity to employ its more traditional analytical and engineering methods. The staff considers that the specific perfomance objectives of 10 CFR Part 60, the detailed siting and other qualitative criteria of 10 CFR Parts 60 and 960, and the technical positions under development by the NRC staff will help assure that the appropriate balance is struck between use of traditional analytical and engineering methods and probabilistic analyses in making licensing findings.
| |
| Although the staff continues to believe that the probabilistic nature of the standards will pose a significant challenge, the staff considers that the standards, in the current fom, can be implemented in a licensing review.
| |
| I hope that this information proves helpful in explaining the staff's views regarding implementation of the EPA standards by the NRC.
| |
| - ess-R rt E. Browning trector D ision of Waste Management i
| |
| l
| |
| * l l l l l t
| |
| i O ,
| |
| | |
| NRR STAFF PRESENTATION TO THE i 'O ACRS
| |
| * e i
| |
| | |
| ==SUBJECT:==
| |
| GESSAR-II PRA SEVERE ACCIDENT CONSEQUENCE RESULTS DATE: SEPTEMBER , 1985 l
| |
| PRESENTER: " Za LJ2N ( GAi f
| |
| REACTOR SYSTEMS BRANCH !
| |
| PRESENTER'S TITLE / BRANCH /DIV: l DIVISION OF SYSTEMS INTEGRATION l PRESENTER'S NRC TEL. NO.: 492 p y i I
| |
| /
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| GESSAR-II SUBCOMMITTEE: !
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| I Figure 15.1 Principal features of MARK III containment ,.
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| : l GESSAR II SSER 2 15-44 i
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| |
| Ex-vessel (core / concrete vaporization) release passes through horizontal j vents into the pool and is also scrubbed. 1 Figure 15.1 GESSAR II Mark III containment: typical fission '
| |
| i product release pathways with drywell intact GESSAR II SSER 4 15-27 l -- - -. .. - _ . _ _ . . _ _ _ _ _ - _ _ _ . _
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| |
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| |
| / PRIMARY SYSTEM GAS FLOW FROM s MERGE CODE 4 DATAREDUCTION/
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| |
| /,FOR LOCAsw
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| ' GAS FLOW FROM SPARC CODE NAUA CODE CORE DEBRIS
| |
| / THCCA P/T 3 HISTORIES FP SCRUBBING M FP TRANSPORT INTER SUBROUTINE g DATA REDUCTION GAS FLOW IN POOL WETWELL MODEL RATES. n CORE / CONCRETE ~
| |
| INTERACTIONS VANESA CODE ; POOL BYPASS ,
| |
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| |
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| |
| CONCRETE 1HTERACTIONS _.,,fP SPECIES, CUANTITIES
| |
| 'AHD SIZE DISTol'IITION walla CODE o
| |
| : ,1 GAS FLOW ( FP TRANSPORT DRYWELL MODEL FLOW DIAGRAM OF ASTP0 CODES CORCON CODE
| |
| , CORE / CONCRETE INTERACTIONS
| |
| | |
| COMPARISON BETWEEN BNL SENSITIVITY STUDY AND BNL MECHANISTIC ANALYSIS (CLASS.1.. LATE.. FAILURE COMPLETE p
| |
| V POOL SCRUBBIN6)
| |
| BNL BNL BNL MECHANISTIC SENSITIVITY SENSITIVITY (LOW)
| |
| SPECIES (HIGH)
| |
| .:. (IR=28 HR) '(IR=13 HR) --
| |
| (TR=13 HR).
| |
| 10 10 10 XE-KR 3 0(-4,) ,3 0(-4) 3 0(-4)
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| O MARK 3 CONTAINPENT FAILURE 110 16 NITERS l
| |
| .d 4 1
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| ! I f .
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| 2 h30IS h L A, S f ,fMS. lb,/CTION ids ,
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| PRO
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| , TION ;
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| .42 .55 1%)
| |
| .03 LOCA ( 1-T-L3 1-SB-El 1-T-E3 .
| |
| O
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| .50 . 50 '
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| bbkbbT (79%)
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| 1-T-E3 - ,
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| ATWS ATWS (8%)
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| T I
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| Table 15.1 Conditional consequem:e's predicted by the staff for internally initiated events and prehability of O occurrence with and without UPPS, por reacter year
| |
| * a Release Early Early Latent Person-category
| |
| * fatality injury fatality rees w/o UPPS w/UPp$
| |
| 1-T-L3 0 0 40 7 x E5** 3 x E-6 9 x E-7 1-T-E3 0 0.0005 200 3 x E6 8 x E-6 1 x E-6 1-T-12Q 0 3 200 3xE6 1 x E-5 1 x E-6 2-T-83 0 0 300 5 x E6 4 x E-6 4 x E-7 ATWS 0 1 400 6 x E6 3 x E-6 3 x E-6 l'T-I2 0 6 500 8 x E6 3 x E-6 3 x E-7 1-58-El 0.006 10 600 S x E6 1 x E-9 1 x E-9
| |
| *See definitions in Table 15.15.
| |
| **7 x E5 = 7 x 105 Notes: ,
| |
| (1) All conditional mean consequences were calculated using the upper range BNL source ters values described in SSER 2.
| |
| (2) The calculations assumed the Shippingport site, with public evacuation within 10 miles and relocation 12 hours after plume passage.
| |
| (3) Hean consequences were computed over 91 different weather conditions. l l
| |
| l
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| ~
| |
| l l
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| l O
| |
| GESSAA II $$ER 4 15-31 l
| |
| * l .
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| | |
| Conditional consequences predicted by the staff for Table 15.2 externally initiated events (seismic) and probability 7 of occurrence, per reactor year Probability Early Latent Person-Release Early fatality rem w/o UPPS w/UPPS fatality injury category
| |
| * 1 x E6** 3 x E-7 3 x E-7 8 600 1-T-L3~ 0.3 7 x E6 6 x E-6 6 x E-6 150 500 ATWS 50 9 x E6 6 x E-5 5 x E-5 200 '600 1-T-I2 70 11 x E6 1 x E-6 1 x E-6 300 700 1-SB-El 100 8 x E6 1 x E-7 1 x E-7 900 600 S E, 250
| |
| *See definitions 8in Table 15.15.
| |
| **1 x E6 = 1 x 10 .
| |
| Notes:
| |
| All conditional consequences were calculated using upper range sou (1) ters values.
| |
| (2) The Shippingport site was assumed.
| |
| (3)
| |
| No public evacuation was assumed; relocation 24 hours after plu passage and no sheltering for severe earthqu -
| |
| assumed.
| |
| (4) The SaE , category was approxiihated using 8MI-2104 infor (Battelle,1984).
| |
| i O .
| |
| 15-32 GESSAR 11 SSER 4
| |
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| J Y o
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| E S =
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| O o g SEISMIC RISK. PERSON-REMS PER UNIT YEAR EFFECT OF GESSAR CONTAINMENT -
| |
| TABLE 15 11 SER SUPPLEMENT 4 EVENT TREE FOR RELEASE TOTAL 1.0SS OF POWil U?PS CATEGORY WITHOUT WITH AND WITHOUT WITH UPPS AND IGNITIERS UPPS UPPS IGNITERS UPPS UPPS 13 13 13 13 1-SB-El 0.3 30 26 26 1-T-L3 03 03 05 05 0.5 05 05 1-S2 (MAX) 05 43 43 43 43 43 43 ATWS --
| |
| 79 69 526 456 1-T-12
| |
| -- -- 170 47 41 65' I-T-E3 12 12 12 12 12 12 V-EVENT 30 31 30 30 31 30 RHR PIPE BREAK 7 7 7 7 7 7 MASSIVE FAILURE 260 263 241 184 TOTAL 632 562 l
| |
| BROOKHAVEN NAll0NAL LABORATORY l} gj j A5500ATED UNIVERSITIES, INC.(llll w
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| |
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| |
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| A12EAS MOST CR. \TlC A L TO j 66'i6MtC EVE.KT CoM6EGuENCG-S '
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| l
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| , souece. TSRM VA LUES Suppe.46Sto64 Pool e PoTeMmeA., #dt SYPA f=5 o G#CuATIoR c4: PuSLtC., -
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| |
| ' Table 15.15 Release categories i
| |
| Release category Description 1-T-L3 Class 1 core-melt transient (e.g., station blackout) with late
| |
| ,' containment failure as a result of overpressurization from gases generated during core-concrete interaction. J Core-melt transient as above with early containment failure result- !1 1-T-E3 ing from local or global hydrogen detonation. However, the drywell is assumed to remain intact and pool scrubbing is maintained. ,
| |
| Core-melt transient. Station blackout with power restored after !
| |
| 1-T-12Q ':
| |
| I hour. Global hydrogen detonation with drywell failure and poten-tial pool bypass; houver most fission products are assumed to be released before the vessel fails and so are retained in the pool.
| |
| Also, core debris is assumed to be quenched.
| |
| 1-T-12 Same as 1-T-12Q but without quench.
| |
| r 1-T-E2 Variations of above core-melt transients where "E" represents early containment failure "I" intermediate time, and "L" late.
| |
| I 1-T-E2Q f 1-T-I3 The "1", "2", and "3" refer to partial, intermediate, and con- '
| |
| 1-T-L2 tinuous scrubbing as defined in Table 15.11 of SSER 2. "Q" refers ,
| |
| to quenched ex-vessel core debris.
| |
| ; 1-SB-El Small-break core-melt transient with early containment failure (drywell) from hydrogen detonation and bypass of suppression pool.
| |
| 1-58-E1Q Same as above but with quench of ex-vessel core debris.
| |
| ! Same as above but drywell remains intact and there is no pool bypass.
| |
| 1-58-E3 1-58-L1 Small-break core-melt transient with late overpressurization failure of containment and partial bypass of the pool, i
| |
| 1-58-L3 Same as 1-58-L1 but with no bypass.
| |
| l
| |
| ; II-T-83 Class 2 core-melt transient with initial failure of containment heat removal causing overpressurization and failure of containment.
| |
| No
| |
| ! Core melt and vessel failure follow the containment failure.
| |
| l pool bypass.
| |
| l l ATWS Anticipated transient without scram and core melt.
| |
| Core-melt accident caused by a very severe earthquake. EarlyAnalysis con-l S E, tainment and drywell failure with suppression pool bypass.
| |
| i l
| |
| values were approximated using BMI-2104 information (Battelle,1984).
| |
| O GESSAR II SSER 4 15-47
| |
| | |
| NRR STAFF PRESENTATION TO THE
| |
| ; O ACRS .
| |
| F+ -
| |
| f
| |
| | |
| ==SUBJECT:==
| |
| GESSAR II STAFF REQUIRED INTERFACES 1
| |
| i DATE: SEPTEMBER 11, 1985 j
| |
| PRESENTER: DINO C. SCALETTI i O-PRESENTER'S TITLE / BRANCH /DIV: PROJECT MANAGER / SSPB / DL i
| |
| PRESENTER'S NRC TEL. NO.: 492-9787 SUBCOMMITTEE: GESSAR II I
| |
| 4 O
| |
| :1 SEVFPF SCCIDENT INTERFACES .
| |
| Supplement !?
| |
| 15.6.2 Quality assurance and interface requirements
| |
| -titility applicants referencing GESSAR II nust provide an evaluation to support the PRA interfaces and assumptions to demonstrate that the PPA's applicebie.
| |
| 15.6.2.3 Internal and external flooding analysis (Pape 15-19)
| |
| Tr.tcrnal flooding-analysis should consider that rupture of lines to the surpressinn pool has the potential for bypass pathway. The impact on plant risk must be addressed.
| |
| External flooding - provide PMF *n'ometion recuired by the S P.P .
| |
| 15.6.P.3 Aircraft Strike (page 15-in)
| |
| Demonstrate that the probability of aircrrft irpact is less than 10-7 15.6.7.2 Parerdous Materials Provide infomation that the risk from hazardous materials is low. Utility applicants wili provide a detemination of the design-besis events with probabilities of greater than 10-7 per year
| |
| , and have potential, consequences serious enough to effect the safety of the plant to the extent that 10 CFR 100 guidelines could be exceeded.
| |
| t 15.6.2.3 Snow and Ice Loading (pane 15-20)
| |
| Assess the risk impact from snow and ice loading Arrerdix C Systems interaction (US!-II (page 15-20)
| |
| (1) Provide systen-level failure modes analyses
| |
| (?) Include RPS, RCIC, RHR, Remote shutdown SBGT and HVAC systems in the FMEA.
| |
| (3) Include 80P systers ir the enalysis (4) Analysis of spatially coupled systens i
| |
| 1 . _ _ - . -- ._. -- _ - - ._
| |
| | |
| D O
| |
| 3 Appendix C Behavior of BWR Mark III Containment, GSI B-10 I . Address staff acceptance criteria for LOCA-related pool dynamic loeds identified in NUPEG-0978 and in Section 6.2.1.8.3 in the
| |
| _1 i GESSAF II SER a '
| |
| ; Appendix C Reliability of oper cycle service 4eo water systems, GSI 51, (page 19)
| |
| To be addressed by utility applicants Appendix C Probability of core mel't due to CCV system, GSI 65, (pace 20)
| |
| - The ma,ior portier of the CCW is outside the scopa of GESSAR Ii l A utility applicant trust show core melt and risk fron en eccident
| |
| ! will result in no sionificant change to PRA.
| |
| l Appendix G CP/rc rule itens Provide required information required by 10 CFP 50.34(f) for l
| |
| those items outside GESSAP. II scope, i
| |
| i i
| |
| i 1
| |
| I i
| |
| 4 1
| |
| | |
| l i Supplement #3 1.E.6.7.3(1.5) Critical component and structures list. (page 15-10) f Develop a critical components and structures list for the t
| |
| .i plant with due considerrtien of Table 15.1. Perform ,
| |
| 7 l fragility analyres of cll critical structures and components and show that they are bounded by the values preserted ir i
| |
| the GESSAR II seismic risk study, and clearly indicate all ,
| |
| suppor*ir:r: essumptions and calculations incorporated into i
| |
| ! +he fragility analyses. In this context, bounding the
| |
| ]
| |
| ! - fragility value means that the plant specific median values shculd be greater than or equal to the GESSAR II median c q ;
| |
| i values and that the plant specific logarithmic standard deviation values should be below or ecuel te the corresponding GESSAR II valuer. For critical components not l
| |
| I included in the CF!!/P. II list, an applicant should satisfy the Case 1 alternate fragilities presented in supplement 3 l i
| |
| ! (Table 15.2).
| |
| ! Site specific hazard function analysis I
| |
| Perform a site specific hazard function analysis, and j l
| |
| i .iustify that the mean and mean plus one standard dev4 tien l
| |
| l of the site specific hazard are bounded by the mean and mean plus or.e standard deviation GESSAP JI seismic hazard j
| |
| function as indicated in Table P-3 cf the 'GESSAR II Seismic Event Uncertainty Analysis," Decerber 19P3.
| |
| i i
| |
| !O i
| |
| i l
| |
| | |
| 4 O
| |
| Seismic analysis interface assumptions For the balance of plant features not included in the GESSAR l
| |
| II cr the Case 1 analysis, and any plant specific seismic vulnerability to be detemined from a plant specific l
| |
| ! walkdown, show that the as-built plett satisfies the assumptions utilized by the CESStP II analysis.
| |
| a d
| |
| 1 4 - in the event that these analyses indicate that the above ;
| |
| creditiens are not met, the utility applicant shall deirenstrate that this does not result in any significant ,
| |
| increase in risk.
| |
| i i O l l i
| |
| I l;
| |
| j i !
| |
| I i !
| |
| i i
| |
| I
| |
| - - _ . . . - _ - _ . . . - . . _ _ _ _ . _ . _ . - . _ , _ _ _ . _ _ _ _ . _ . , _ . . , , . _ _ _ _ _ . . _ _ _ _ . _ . - _ - - . .__ _ - _ _ . _ - , ~ . _ _ _ _ , _ . _ _ _ . _ _ _ _ . - .
| |
| | |
| Supplement #4
| |
| !5.6 fontainment ventino procedures (page 15-2)
| |
| Provide guidelines apri procedures for containment ventice below :
| |
| the ultimate containment pressure-carryirg capability of 83 PSIF 15.6.3.4.t. PCIC room cooling Utility applicants must investigate what actions are available to facilitate RCIC roon cooling for extended operation during J
| |
| l a station ticckrut.
| |
| Appendix C Safety implications of control systems, UST A-47, (page 3) j -
| |
| l Provide the necessary evaluation of control systems required by -i
| |
| ?,
| |
| l f:l!P.EG-p*79andthatwillberequiredbyresolutionofUSI j A-47, 2
| |
| Appendix C fr.terfacinn LOCA, GSI 105, (page 10)
| |
| Denonstrate the intended design capability of the isolation vt ves, at least on a prototype basis, by performing a closing j
| |
| and opening test with full design differential pressure and flow I
| |
| across the valve disk. Such a design test is recormended in f - addition to the leak and operability testing of isolation valves i
| |
| ; as required by the BWR Standard Technical Specifications.
| |
| In a#itice, to the interfaces listed above the staff will condition the FDA to reovire the following modifications j discussed in $$ER Section 15.F.3.E.
| |
| l
| |
| .I
| |
| : 1) Seismic upgrade to UPPS
| |
| ; i l 2) Dedicated pewr supply to hydrogen igniter system ,
| |
| 3)10-hourstationbatteries
| |
| : 4) Ability to power a de battery charger from the backup igniter
| |
| }
| |
| ; pew r supply
| |
| ! r
| |
| | |
| i e
| |
| i i .
| |
| US1 A-43, CONTAINMENT EMERGENCY SUMP PERFORMANCE PROPOSEC CHANGES TO RG 1.82 i
| |
| l AND l RESOLUTION STATUS i1 i PREPARED FOR:
| |
| j 305TH ACRS MEETING O BY l
| |
| i
| |
| ! A. W. SERKIZ, TASK MANAGER i
| |
| GENERIC ISSUES BRANCH DIVISION OF SAFETY TECHNOLOGY l
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| OFFICE OF NUCLEAR REACTOR REGULATION I
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| l SEPTEM8ER 12, 1985 i ,
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| l TECHNICAL BACKGROUND
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| : 1) THE TECHNICAL FINDINGS RELATED TO USI A-43 ARE REPORTED IN NUREG-0897
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| ! REVISION 1B WHICH WILL BE PUBLISHED UPON RESOLUTION OF THIS ISSUE.
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| : 2) ADDITIONS AND MODIFICATIONS HAVE BEEN MADE TO REFLECT: A) INPUTS RECEIVEDFORNUREG-0897DURINGTHE"FORCOMMENT" PERIOD,B)RESULTSOF ADDITIONAL EXPERIMENTS AND C) ADDITIONAL INFORMATION RECEIVED FROM THE DIAMOND POWER COMPANY AND OWENS-CORNING FIBERGLASS. INC.
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| : 3) THESE FINDINGS REVEAL A NEED TO REVISE RG 1.82. IN PARTICULAR THE 50% SCREEN BLOCKAGE CRITERION CONTAINED IN SECTION C.7 0F THE ACTIVE VERSION IS REPLACED WITH A REQUIREMENT TO ASSESS DEBRIS BLOCKAGE EFFECTS ON A PLANT SPECIFIC BASIS.
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| : 4) THE ACRS HAS BEEN PROVIDED COPIES OF THE PROPOSED RG 1.82, REVISION I, IN COMPARATIVE TEXT. THIS GUIDE HAS ALSO BEEN ISSUED TO PREVIOUS RESPONDEES WHO PROVIDED REVIEW COMMENTS.
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| 2 ,1 OVERVIEW OF REVISIONS TO RG 1.82
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| ]
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| : 1) RG 1.82 HAS BEEN REVISED TO INCLUDE BOTH BWRs AND PWRs. PROVISION FOR POST-LOCA RECIRCULATION CAPABILITY IS GENERIC TO BOTH TYPES OF t REACTORS.
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| : 2) THE CURRENT 50% BLOCKAGE CRITERION HAS BEEN DELETED; GUIDANCE FOR l
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| l ASSESSING PLANT SPECIFIC DEBRIS BLOCKAGE EFFECTS IS PROVIDED IN APPENDIX A.
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| : 3) THE RG HAS BEEN REVISED TO REFLECT SUMP (OR SUCTION INLET) HYDRAULICS
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| ! FINDIhGS AND REMOVES VORTEX OBSERVATIONS AS THE BASIS TO QUANTIFY AIR INGESTION LEVELS. APPENDIX A ALSO PROVIDES CONSERVATIVE GUIDELINES i FOR ESTIMATING POTENTIAL AIR INGESTION LEVELS BASED ON FULL SCALE TESTS.
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| 1
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| : 4) THE RG HAS BEEN REVISED TO REQUIRE ASSESSMENT OF DEBRIS AND PARTICULATE EFFECTS ON RHR AND CSS PUMP BEARING AND SEAL ASSEMBLIES.
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| 3 STATUS OF IMPLEMENTATION OF RG 1.82, REVISION 1
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| : 1) RG 1.82, REV. 1 HAS BEEN REVISED AND OBTAINED DURING THE COURSE OF RESOLVING U51 A-43 TO REFLECT TECHNICAL FINDINGL.
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| : 2) IMPLEMENTATION IS CONCURRENT WITH THE RESOLUTION OF USI A-43.
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| : 2) RG 1.82, REVISION 1 WOULD BECOME EFFECTIVE 6 MONTHS FOLLOWING ISSUANCE j OF THE GUIDE AND WOULD' APPLY TO FUTURE CP APPLICATIONS AND PRELIMINARY DESIGN APPROVALS (PDAs) THAT ARE DOCKETED AFTER SIX (6) MONTHS OF ISSUANCE,ANDAPPLICATIONSFORFINALDESIGNAPPROVALS(FDAs)TH4THAVE NOT RECEIVED APPROVAL AT SIX (6) MONTHS FOLLOWING ISSUANCE OF THE R 4
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| 1 CURRENT RESOLUTION STATUS OF USI A-43
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| : 1) A REVISED REGULATORY ANALYSIS HAS BEEN PREPARED (NUREG-0869. REVISION IB, JUNE 1985 DRAFT).
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| t
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| : 2) THE ACRS COMBINED FLUID DYNAMICS /ECCS SUBC0PetITTEE WAS BRIEFED ON 8/27/85 REGARDING CHANGES TO RG 1.82 AND THE RESOLUTION STATUS OF USI A-43.
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| : 3) A CRGR MEETING WAS HELD ON 9/9/85 TO DISCUSS THE PROPOSED RESOLUTION ACTIONS. AGREEMENT WAS REACHED TO PROCEED WITH THE RECOP9 TENDED ACTIONS, WITH ALSO THE UNDERSTANDING THAT THE RG & SRP IMPLEMENTATION WORDING WOULD BE REVISED TO MORE CLEARLY REFLECT THE APPLICABILITY OF THESE REGULATORY CHANGES.
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| REVISED IMPLEMENTATION LANGUAGE DUE TO CONCERNS RAISED REGARDING IMPLEMENTATION LANGUAGE IN THE PROPOSED REVISIONS TO RG 1.82 AND SRP SECTION 6.2.2 THE FOLLOWING LANGUAGE IS PROPOSED AS A SUBSTITUTE:
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| "IS APPLICABLE T0:
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| : 1) CONSTRUCTION PERMIT APPLICATIONS AND PRELIMINARY DESIGN APPROVALS (PDAs) THAT ARE DOCKETED AFTER SIX (6) MONTHS FOLLOWING ISSUANCE OF REGULATORY GUIDE 1.82, REVISION 1.
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| : 2) APPLICATIONS FOR FINAL DESIGN APPROVAL (FDAs), FOR STANDARDIZED DESIGNS WHICH ARE INTENDED FOR REFERENCING IN FUTURE CONSTRUCTION PERMIT APPLICATIONS, THAT HAVE NOT RECEIVED APPROVAL AT SIX (6)
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| MONTHS FOLLOWING ISSUANCE OF REGULATORY GUIDE 1.82, REVISION 1.
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| OUR INTENT IS TO MAKE CLEAR THAT RESOLUTION OF THIS USI WILL NOT IMPACT l PLANTS ALREADY UNDER CONSTRUCTION.
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| * 6 PROPOSED RESOLUTION ACTIONS FOR USI A-43
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| : 1) ISSUE THE STAFF's TECHNICAL FINDINGS (NUREG-0897, REVISION IS) FOR USE AS A TECHNICAL INFORMATION SOURCE.
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| ISSUE SRP SECTION 6.2.2, REVISION 4 AND RG 1.82, REVISION 1. THESE 2)
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| REVISIONS REFLECT THE STAFF's TECHNICAL FINDINGS REPORTED IN NUREG-0897, REVISION 18. THIS REVISED LICENSING GUIDANCE WOULD APPLY ONLY TO FUTURE CONSTRUCTION PERMIT APPLICATIONS, PRELIMINARY DESIGN APPROVAL (PDAs) AND FINAL DESIGN APPROVALS (FDAs) WHICH HAVE NOT RECEIVED APPROVAL AND WOULD BE EFFECTIVE 6 MONTHS FOLLOWING ISSUANCE.
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| i
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| : 3) ISSUE A GENERIC LETTER FOR INFORMATION ONLY TO ALL HOLDERS OF AN OPERATING LICENSE OR CONSTRUCTION PERMIT OUTLINING THE SAFETY CONCERNS REGARDING POTENTIAL DEBRIS BLOCKAGE AND RECIRCULATION FAILURE DUE TO INADEQUATE NPSH. ITISSUGGESTED(BUTNOTREQUIRED)THATLICENSEES UTILIZE RG 1.82, REVISION 1 AS GUIDANCE FOR CONDUCT OF THE 10 CFR 50.59 REVIEW FOR FUTURE PLANT MODIFICATIONS INVOLVING REPLACEMENT OF INSULATION ON PRIMARY SYSTEM PIPING AND/OR EQUIPMENT. IF, AS A RESULT ;
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| 0F NRC STAFF REVIEW OF LICENSEE ACTIONS ASSOCIATED WITH REPLACEMENT OR l MODIFICATION TO INSULATION, THE STAFF DECIDES THAT SRP 6.2.2, REY. 4 [
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| AND/0R RG 1.82, REV. 1 CRITERIA SHOULD BE (OR SHOULD HAVE BEEN) APPLIED i BY THE LICENSEE, AND THE STAFF SEEKS TO IMPOSE THESE CRITERIA THEN THE ,
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| i NRC WILL TREAT SUCH AN ACTION AS A PLANT SPECIFIC BACKFIT PURSUANT TO 10 i CFR 50.109. .
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| O EXCLUSION OF DYNAMIC LOADING EFFECTS ASSOCIATED WITH POSTULATED PIPE BREAKS ACRS SEPT, 12, 1985 o INTRODUCTION R. J. B0SNAK 5 MIN, o HISTORY AND STATUS J. O'BRIEN 10 MIN, 0F RULECHANGES (LIMITED a BROAD SCOPE) o FOREIGN PRACTICE J. O'BRIEN 5 MIN, o PLANT ACTIONS: R. KLECKER 10 MIN, O ewR xAiN '00e o PLANT ACTIONS: R. J. B0SNAK 10 MIN.
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| ARBITRARY INTER-MEDIATE BREAKS o TWO RECENT R. J. B0SNAK 10 MIN, PROPOSALS CRYSTAL RIVER-3 RCP SNUBBERS BEAVER VALLEY-2-B0P.(CONCEPTUAL)
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| O
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| INTRODUCTION
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| ({])
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| o ACRS LETTER JUNE 14, 1983 I o STABLE CRACK SIZE BY FRACTURE MECHANICS TECHNIQUES:
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| 1 LEAKAGE DETECTION WITH MARGIN BEFORE CRACK IS UNSTABLE.
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| ! OK FOR PWR PRIMARY LOOP PIPIhG
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| : l o DECOUPLING SSE a LOCA-ANALYSIS BY LLL, VEND 0R BY VENDOR ,
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| ; CAVEAT-HEAVY COMPONENT SUPPORT INTEGRITY o ADVISE ACRS OF SEGULATION CHANGES AND POSITIONS OF FOREIGN REGULATORY BODIES o EXTENSION TO OPERATING PLANTS CAVEAT-CLEAR ASSURANCE OF QUALITY OF DESIGN & CONSTRUCTION
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| !O I
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| O
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| _ ~ . - _ . . , - _ _ ,
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| IMPLEMENTATION POLICY (NT0L'S)
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| SCHEDULAR EXEMPTIONS ONCE LEAK BEFORE BREAK PERFORMANCE HAS BEEN ESTABLISHED INCLUDING LEAKAGE DETECTION CAN ELIMINATE DYNAMIC LOADING EFFECTS:
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| ! 1. PIPE WHIP, 2. JET IMPISGEMENT, 3. ASYMMETRIC PRESSURIZATION TRANSIENTS (USI A-2), 4. BREAK ASSOCIATED DYNAMIC TRANSIENTS IN UNBROKEN PORTIONS MAINLOOP AND CONNECTED BRANCH LINES PERMITS: REMOVAL WHIP RESTRAINT STRUCTURES, JET IMPINGEMENT BARRIERS CANNOT
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| ~
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| CHANGE CONTAINMENT DESIGN, CHANGE ECCS DESIGN, CHANGE EQUIPMENT QUALIFICATION (ENVIRONMENTAL PROFILE), CHANGE HEAVY COMPONENT SUPPORT MARGINS l
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| i r
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| I f
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| PLANT ACTIONS:
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| (-}.
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| '- PWR MAIN LOOP REVIEW STATUS OWNER'S GROUP W A-2 FACILITIES REVIEW COMPLETE, GENERIC LETTER 84-04 (TECH REVIEW COMPLETE FOR COOK 1, 2, GINNA AND POINT BEACH 1, 2. NO RESPONSE FROM REMAINING 11 FACILITIES.)
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| CESSAR, SYS, 80 REVIEW COMPLETE, LTR TO CE 10/11/84 B&W (BAW-1847) REVIEW UNDERWAY GESSAR II REVIEW UNDERWAY NT0L'S (22 PWR UNITS, MAIN LOOP PIPING ONLY)
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| FACILITIES SER COMPLETE EXEMPTION GRANTED COMANCHE PEAK 1, 2 05/25/84 08/28/84 (UNIT 1, IMP. SHIELDS)
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| V0GTLE 1, 2 08/20/84 02/05/85 O CATAWBA 1, 2 09/20/84 04/23/85 (UNIT 2)
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| SOUTH TEXAS 1, 2 10/15/84 PALO VERDE 1, 2 a 3 10/31/84 CALLAWAY/ WOLF CREEK 12/11/84 . 03/11/85(WOLF CREEK)
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| MILLSTONE 3 01/15/85 06/05/85 BYRON 1, 2 01/15/85 BRAIDWOOD 1, 2 01/15/85 SEABROOK 1, 2 01/18/85 BEAVER VALLEY 2 01/18/85 SHEARON HARRIS 1 02/04/85 06/05/85 OTHER APPLICATIONS PRAIRIE ISLAND 1 REVIEW UNDERWAY INDIAN POINT 3 REVIEW UNDERWAY (N0 ACTION ON THE FOLLOWING PENDING BROAD RULE CHANGE)
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| ( NINE MILE POINT 1 SUBMITTAL RECEIVED (SECONDARY LINES)
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| CATAWBA 1, 2 SUBMITTAL RECEIVED FOR RHR, PRESSURIZER SURGE AND ACCUMULATOR INJECTION LINES
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| . . . _ . _ _ . ~ . .
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| PLANT ACTIONS:
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| ARBITRARY INTERMEDIATE BREAKS o BREAKS POSTULATED AT TERMINAL END AND AT INTERMEDIATE LOCATIONS WHERE STRESS OR USAGE FACTOR (FATIGUE) EXCEED
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| ! SPECIFIED LIMITS ,
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| o IN WELL DESIGNED SYSTEMS, THERE ARE NO INTERMEDIATE LOCATIONS EXCEEDING LIMITS, ARBITRARILY SELECT TWO.
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| o PRC RECOMMENDS CAVEATS EMPLOYED AT START OF AIB PROGRAM BE DROPPED. (STRESS CORROSION CRACKING, LARGE UNANTICIPATED DYNAMIC LOADS, FATIGUE IN FLUID MIXING SITUATIONS o EQUIPMENT THROUGHOUT PIPING RUN QUALIFIED FOR NON-DYNAMIC EFFECTS OF A NON-MECHANISTIC PIPE BREAK WITH GREATEST i
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| CONSEQUENCES ON EQUIPMENT 2
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| PLANTS APPROVED (15) o CATAWBA 2, V0GTLE'1 & 2, SEABROOK 1, SHEAR 0N HARRIS-1, SOUTH TEXAS 1 a 2, COMANCHE PEAK 1 AND 2, BYRON 1 a 2, BRAIDWOOD 1
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| & 2, BEAVER VALLEY 2, CLINTON 1 o SRP 3.6.2 NOW BEING REVISED WITH CRGR PACKAGE IN PREPARATION
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| RECENT PRELIMINARY PROPOSALS CRYSTAL RIVER-3 1 o REACTOR C0OLANT PUMP SUPPORTS: CURRENTLY: 32 1000-2000 KIP SNUBBERS; PROPOSED: 8 SMALLER SNUBBERS (400 KIP) AND 4 RIGID RESTRAINTS o BENEFITS: UNRELIABILITY OF LARGE SNUBBERS, ALARA, BETTER RELIABILITY OF SMALLER UNITS, IMPROVED THERMAL FLEXIBILITY o MARGINS REVISED, RELIABILITY INCREASED o NEEDS LIMITED SCOPE RULE CHANGE IN PLACE BEAVER VALLEY-2
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| ]o WHIPJET PROGRAM DEMONSTRATE VIA TEST AND ANALYSIS LEAK BEFORE BREAK APPROPRIATE FOR B0P SYSTEMS o ELIMINATE 136 B0P RUPTURE MITIGATION ITEMS BY DEMONSTRATING LBB PERFORMANCE VIA FRACTURE MECHANICS o LBB PERFORMANCE FOR SYSTEMS NOT RELATIVELY IMMUNE TO STRESS CORROSION, FATIGUE, AND LARGE DYNAMIC LOADS o NEEDS BROAD SCOPE RULE CHANGE IN PLACE I
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| O 1
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| _ , ~ - - , _ _ - _ , ~ , _ - - _ _ _ _ , _ _ - _ - _ - _ . _ _ . _ - - _ , _ - _ - - _ - . _
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| O i
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| EXCLUSION OF DYNAMIC LOADING EFFECTS ASSOCIATED WITH POSTULATED ;
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| PIPE BREAKS ACRS SEPT. 12, 1985 l o INTRODUCTION R. J. BOSNAK 5 MIN. !
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| o HISTORY AND STATUS J. O'BRIEN 10 MIN. {
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| OF RULECHANGES !
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| (LIMITED & BROAD SCOPE) f l'
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| 0 FOREIGN PRACTICE J. O'BRIEN 5 MIN.
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| I I o PLANT ACTIONS: R. KLECKER 10 MIN. !
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| O ewR MAIN t00e !
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| t
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| : o PLANT ACTIONS: R. J. B0SNAK 10 MIN. ,
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| ARBITRARY INTER- !
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| MEDIATE BREAKS !
| |
| o TWO RECENT R. J. B0SNAK 10 MIN. :
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| PROPOSALS :
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| CRYSTAL RIVER-3 RCP SNUBBERS I BEAVER VALLEY-2-B0P (CONCEPTUAL) e
| |
| ~
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| i O l i
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| , - . ,. - - . _ ~ . , . . , - - - _ _ , , . ~ ' ~.l--.
| |
| | |
| INTRODUCTION
| |
| ({})
| |
| o ACRS LETTER JUNE 14, 1983 o STABLE CRACK SIZE BY FRACTURE MECHANICS TECHNIQUES:
| |
| LEAKAGE DETECTION WITH MARGIN BEFORE CRACK IS UNSTABLE.
| |
| OK FOR PWR PRIMARY LOOP PIPING o DECOUPLING SSE a LOCA-ANALYSIS BY LLL, VENDOR BY VENDOR CAVEAT-HEAVY COMP 0NENT SUPPORT INTEGRITY o ADVISE ACRS OF REGULATION CHANGES AND POSITIONS OF FOREIGN REGULATORY BODIES o EXTENSION TO OPERATING PLANTS CAVEAT-CLEAR ASSURANCE OF QUALITY OF DESIGN & CONSTRUCTION O
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| 0-1 J
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| lO i
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| N
| |
| | |
| () IMPLEMENTATION POLICY (NT0L'S)
| |
| SCHEDULAR EXEMPTIONS ONCE. LEAK BEFORE BREAK PERFORMANCE HAS BEEN ESTABLISHED INCLUDING LEAKAGE DETECTION CAN ELIMINATE DYNAMIC LOADING EFFECTS:
| |
| : 1. PIPE WHIP, 2. JET IMPINGEMENT, 3. ASYMMETRIC PRESSURIZATION TRANSIENTS (USI A-2), 4. BREAK ASSOCIATED DYNAMIC TRANSIENTS IN UNBROKEN PORTIONS '
| |
| MAINLOOP AND CONNECTED BRANCH LINES PERMITS: REMOVAL WHIP RESTRAINT STRUCTURES, JET O IMPINGEMENT BARRIERS CANNOT CHANGE CONTAINMENT DESIGN, CHANGE ECCS DESIGN, CHANGE EQUIPMENT QUALIFICATION (ENVIRONMENTAL PROFILE), CHANGE HEAVY COMPONENT SUPPORT MARGINS 1
| |
| : O i
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| l _-
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| | |
| PLANT ACTIONS:
| |
| (V-~) PWR MAIN LOOP REVIEW STATUS OWNER'S GROUP W A-2 FACILITIES REVIEW COMPLETE, GENERIC LETTER 84-04 (TECH REVIEW COMPLETE FOR COOK 1, 2, GINNA AND POINT BEACH 1, 2. NO RESPONSE FROM REMAINING 11 FACILITIES.)
| |
| CESSAR, SYS. 80 REVIEW COMPLETE, LTR TO CE 10/11/84 BaW (BAW-1847) REVIEW UNDERWAY GESSAR II REVIEW UNDERWAY NT0L'S (22 PWR UNITS, MAIN LOOP PIPING ONLY)
| |
| FACILITIES SER COMPLETE EXEMPTION GRANTED COMANCHE PEAK 1, 2 05/25/84 08/28/84 (UNIT 1, IMP. SHIELDS) r- V0GTLE 1, 2 08/20/84 02/05/85 l- CATAWBA 1, 2 09/20/84 04/23/85 (UNIT 2)
| |
| SOUTH TEXAS 1, 2 10/15/84 PALO VERDE 1, 2 & 3 10/31/84 CALLAWAY/ WOLF CREEK 12/11/84 03/11/85(WOLF CREEK)
| |
| MILLSTONE 3 01/15/85 06/05/85 BYRON 1, 2 01/15/85 BRAIDWOOD 1, 2 01/15/85 SEABROOK 1, 2 01/18/85 BEAVER VALLEY 2 01/18/85 SHEARON HARRIS 1 02/04/85 06/05/85 OTHER APPLICATIONS PRAIRIE ISLAND 1 REVIEW UNDERWAY INDIAN POINT 3 REVIEW UNDERWAY (N0 ACTION ON THE FOLLOWING PENDING BROAD RULE CHANGE)
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| () NINE MILE POINT 1 CATAWBA 1, 2 SUBMITTAL RECEIVED (SECONDARY LINES)
| |
| SUBMITTAL RECEIVED FOR RHR, PRESSURIZER SURGE AND ACCUMULATOR INJECTION LINES
| |
| | |
| r
| |
| / PLANT ACTIONS:
| |
| ARBITRARY INTERMEDIATE BREAKS o BREAKS POSTULATED AT TERMINAL END AND AT INTERMEE LOCATIONS WHERE STRESS OR USAGE FACTOR (FATIGUE)
| |
| SPECIFIED LIMITS o IN WELL DESIGNED SYSTEMS, THERE ARE NO INTERMEDIf LOCATIONS EXCEEDING LIMITS. ARBITRARILY SELECT T o PRC RECOMMENDS CAVEATS EMPLOYED AT START OF AIB P DROPPED. (STRESS CORROSION CRACKING, LARGE UNANT DYNAMIC LOADS, FATIGUE IN FLUID MIXING SITUATIONS o EQUIPMENT THROUGHOUT PIPING RUN QUALIFIED FOR NON EFFECTS OF A NON-MECHANISTIC PIPE BREAK WITH GREA CONSEQUENCES ON EQUIPMENT PLANTS APPROVED (15)
| |
| ~
| |
| o CATAWBA 2, V0GTLE 1 & 2, SEABROOK 1, SHEARON HARR TEXAS 1 & 2, COMANCHE PEAK 1 AND 2, BYRON 1 & 2,
| |
| & 2, BEAVER VALLEY 2, CLINTON 1 o SRP 3.6.2 NOW BEING REVISED WITH CRGR PACKAGE IN o -
| |
| | |
| RECENT PRELIMINARY PROPOSALS
| |
| (}})
| |
| CRYSTAL RIVER-3 o REACTOR COOLANT PUMP SUPPORTS: CURRENTLY: 32 1000-2000 KIP SNUBBERS; PROPOSED: 8 SMALLER SNUBBERS (400 KIP) AND 4 RIGID RESTRAINTS o BENEFITS: UNRELIABILITY OF LARGE SNUBBERS, ALARA, BETTER RELIABILITY OF SMALLER UNITS, IMPROVED THERMAL FLEXIBILITY o MARGINS REVISED, RELIABILITY INCREASED o NEEDS LIMITED SCOPE RULE CHANGE IN PLACE 1
| |
| BEAVER VALLEY-2 o WHIPJET PROGRAM
| |
| ({]) DEMONSTRATE VIA TEST AND ANALYSIS LEAK BEFORE BREAK APPROPRIATE FOR B0P SYSTEMS o ELIMINATE 136 B0P RUPTURE MITIGATION ITEMS BY DEMONSTRATING LBB PERFORMANCE VIA FRACTURE MECHANICS l 0 LBB PERFORMANCE FOR SYSTEMS NOT RELATIVELY IMMUNE TO STRESS CORR 0SION, FATIGUE, AND LARGE DYNAMIC LOADS i
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| o NEEDS BROAD SCOPE RULE CHANGE IN PLACE l
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| RULL ELL PROPOSED JULY 85 JAN 86 2
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| FINAL MC 85 JUNE 86 1.. LIMITED SCOPE RULE BASED ON M SOLUTicN OF USI A-2 PREVIOUSLY I
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| REVIEWED AND EW ORSED SY ACRS AND CR6R.
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| : 2. DEVELOPENT OF KW SAP 3.6.X M6 INS JUNE 1986 TO SPECIFY REQUIRE-ENTS AND ACCEPTANCE CAITEAIA POR IMPLEENTING LEAK-BEFORE-BREAK.
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