ML22230A112
| ML22230A112 | |
| Person / Time | |
|---|---|
| Issue date: | 09/25/1979 |
| From: | NRC/OCM |
| To: | |
| References | |
| Tran-M790925 | |
| Download: ML22230A112 (29) | |
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!@URN TO SECRETARIAT RECORDS
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"i Transcript of Proceedings t
l NUCLEAR REGULATORY COMMISSION
~o BRIEFING ON INCIDENT AT NORTH ANNA (Open to Public Attendance)
Tuesday, September 25, 1979 Pages 1 -
26 Prepared by:
C.H. Brown Office of the Secretary
DISCLAIMER This is an unofficial transcript of a meeting of the United Sta:tes Nuclear Regulatory Commission held on September 25, 1979 in tfue Commission 1s offices at 1717 H Street, N. W., \\./ashington, D. C.
The meeting was open to public attendance and observation.
This transc.npt has not been reviewed, corrected, or edited, and it may contain inaocuracies.
The transcript is intended solely for general informational pu:1'qJOses.
As provided by 10 CFR 9. 103, it is not part of the formal or infonr,31 record of decision of the matters discussed.
Expressions of opin:i:orn in this.transcript do not necessarily reflect final determinations or beliefs.
tfo pleading or other paper may be filed with the ~ommissia;n i:1 any proceeding as the result of or addressed to any statement or argument contained herein, except as the Commission may auth'orize.
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.12 13 15 16 17 18 19 20 21 22 23 24 25 UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION Briefing on In9ident at North Anna (Open to Public Attendance)
Commissioner's Conference Room 1717 H Street, N.W.
Washington, D. C.
Tuesday, September 25, 1979 1
The'Commission met, pursuant to notice, at 5:30 p.m.,
Victor Gilinsky, Acting Chairman of the Commission, presiding.*
COMMISSIONERS PRESENT:
ALSO Commissioner Gilinsky Commissioner Kennedy Commissioner Bradford Commissioner Ahearne PRESENT:
V. Stello L. Gossick E. Case E. Jordan
- s. Chilk L. Bickwit"
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P R O C E E D I N G S COMMISSIONER GILINSKY:
Why don't we get started.
Early this morning, shortly after 6:00 o'clock, the North Anna Unit 1 Stati6n shut itself off automatically.
At some later point, levels of radioactivity,*,above normal were recorded in the Auxilliary Building leading to the evacuation of that building.
We are here to hear the details of that occurrence from Mr. Stello, the Director of our Office of Inspection and Enforcement.
I hope you will tell us, not only about the details of the occurrence, but also the health and safety significance as you see it, the NRC response, what we have done, what we are doing; and I would like to hear, and I think the other Commissioners would like to hea~ how the system of notification, both from the licensee and up our own chain worked in this case.
Mr. Stello.
MR. STELLO:
Well, thank you.
I will start by trying to very briefly character-ize, as best as we understand it at this time, and I need to get a caveat right at the beginning,that in a situation like this, where any numbers that I might use or times or precise information, we, obvxousJy,.. will *,need to verify.
I can't say that we have as accurate.*
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.18 19 20 21 22 23 24 25 information as I**JWou,I.d'._like to'have, but J;'m convinced it is more than accurate eno~gh to speak to the bottom line question, "health and safetyoto the public."
If we might have that first slide.
(Slide)
I have a picture or schematic of a PWR which doesn/;t describe the particular plant in operation, but it will be used just to illustrate some points that I think are important in terms of what happened in the plant.
3 At about 6:13 a.m. this morning, the turbine tripped from a high feedwater heater level.
It is not shown on this slide. It is part of the secondary system that is outside of the containment.
The resultant high feedwater level caused a:..,;
turbine to trip, which in turn, caused the reactor to trip.
Ip the process of the reactor tripping, there was still substantial energy being removed in the steam generator, because there was a steam dump valve that failed.to close.
The fact that it failed to close caused the
.primary coolant system to shrink in volume and decrease the pressure of the system.
This continued decrease*
caused the emergency core cooling systems to actuate automatically as they are designed to do, and they did j'
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. 14 15 16 17 18 19 20 21 22 23 24 25 automatically come on when their set point was reached, which was 1765 psia.
4 The minimum pressure that was reached during the transient was 1760 psia.
All of the engineered safety injection systems operated as they were designed.
The cooldown rate.was in excess of what would normally be allowed because of the addition of the water, but*:that cooldown rate caused the primary coolant to cool down to where there was substantial sub-cooling, that is, the concern for voids in the primary system was not ther~ based on the information we had.
The indication that we have right now is that there was a substantial margin of sub-cooling, an estimate of about 100 degrees Fahrenheit of sub-cooling during the transient, which is strongly suggested that no voids were present.
The requirements that we evolved as the result of the Three Mile Island, which required them to continue to operate the high pressure pumps, they continued to operate the two of them for 15 minutes and the second they had 15 minutes, turn one off and kept the second pump on for 20 minutes.
There was no loss of coolant accidertt.
The~relief valve did open up as it was designed. After the pressure started to build back up, it opened up and functioned correctly, it did not stay open~
The safety valves, as best we understand now, did
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not lift.
COMMISSIONER BRADFORD: When was the dump valve closed'; the steam dump valve?
MR. STELLO:
I don't have an answer to that question.
We have -- I should have said at the outset, what we are doing is.we are sending a total of about 10 people, who are now on their way and have been since about 2:30 COMMISSIONER GILINSKY:
We have a Resident Inspector at that site, don't we?
MR. STELLO:
There was a Resident Inspector, and he was there since about 7:00 o'clock this morning, and he was joined by another inspector shortly thereafter.
There have been two inspectors there most of the day.
I have sent one of my Division Directors, Norm Moseley, as the senior NRC representative on-site.
Dr. Ross is going down with a contingent of people, and I will be getting some fac:tµa1;_:inforriiation::.<to answer some of these detailed questions when they have had a chance to look at the actual strip charts and the data reduction in the plant.
So there are some questions that I certainly won't be 'able to answer.
There was -- As the result of the opening of the power operated relief valve, a discharge of water over ihto the quench tank, and I can't see it on that
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picture -- but you recall, th~.quench tank is a tank that is used to quench the steam that is discharged from the power operated relief valve, which goes to the quench tank, and if too much water builds up in there, or too much pressure, there is a diaphragm on it which opens, and would normally spillariy excess water over into the containment sump which you can see on here (ref'erririg_to the slide).
We have an indication that there is a possibili ty;::that the rupture:'.disci::.:may have opened as it should have, on the quench tank, but do not have any indication that the water,. -"=.:1.there was any water that went over into -- any unusual amounts of water went over into the sump.
It functioned properly, so you would not expect that to be the case.
The levels of radioactivity inside of the containment, from the point at which the reactor scram on forward,started to decrease, which is what you would expect: unless you are adding radioactive material to it, since the primary source is the radiation inside the containment is from the reactor itself while it is operating.
There was, however -- relatively speaking, an increase in the particulate amount of radioactivity in the containment, which could mean that that rupture disc did plow out, allowing some particulates, which are
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normally in the primary cooling system, to get into the containment, and those have fallen back to essentially normal levels, but the overall radiation level in the containment, we did get confirmed, was decreasing. There was no COMMISSIONER BRADFORD:
How high did it go?
MR. STELLO:
It was running prior to the accident, the particulate levels, on the level of about 10 to the 4th counts per minute, and it increased about 10 to the 6th counts per minute, and then it started on its way back down thereafter.
up to COMMISSIONER KENNEDY: And where is it now*at the last MR. STELLO:
When I spoke to him last, the characterization was at about the level it was at the beginning of the transient, near:that 1evel.
COMMISSIONER KENNEDY:
About 10 to the minus 4th?
MR. STELLO: About 10 to the minus 4th, some factor times that.*
I would be very cautious in using the numbers until we have had people actually look at the strip charts.
The amount of radiation, though, in the Auxilliary Building did increase during the transient.
To characterize that increase, it increased at about --
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COMMISSIONER GILINSKY:
Can you translate that into milli-r~per hour?
MR. STELLO:
I'm going to try to do that to the ultimate at the site boundary, but a rough number is -- the MPC, if you had that value for the full year at the MPC, it would give you on the order of like 500 millirem, which is the allowable amount of radiation.
COMMISSIONER GILINSKY:
Part 20.
MR. STELLO:
Part 20.
I will be getting back to that number in a moment.
First, the numbers are, it was about -- shortly after on the order of a half an hour.
I don't have the precise time that it began to rise.
It hit::a :peak of about 155 times MPC at 7:00 o'clock.
At 8:00 o'clock it was COMMISSIONER KENNEDY: Did you say 155 times?
MR. STELLO:
Times the MPC.
At about 8:00 o'clock it was down to about 1.5 times the MPC, and then came down to values of a fraction of the MPC thereafter.
This activity, it is in the Auxilliary Building, goes up through vents that are -- filtering vents in the
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- 14 15 16 17 18 19 20 21 22 23 24 25 Auxilliary Building, and from bhere goes out those stacks, then as part of the normal operation, this activity would get into the environment through that source.
They did take samples at those vents;~-.at about 7: 30, following that transient, and-J:.those samples indi-9 cated that they were here, I've got to be very careful about the numbers -- at about the MPC value at the stack.
COMMISSIONER GILINSKY: When was the peak of the concentration in the Auxilliary Building?
MR. STELLO:
The peak was at 7:05, it was 155, and about an hour later, :'_it was down about two orders in magnitude, to about 1.5.
MR. CASE: That was the measured peak."
There may not have been a coincidence between the measurement in the peak, but that was the measured peak.
COMMISSIONER GILINSKY:
It is not a continuous measurement?
MR. CASE: That's not my understanding.
Is that yours?
MR. STELLO:
The measurement that I gave you was from an actual taking of a sample at 7:30.
specifics COMMISSIONER GILINSKY: An air sample?
The
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10 COMMISSIONER GILINSKY:
Well, let's see, we are talking about the concentration in.the Auxilliary Building and ---
COMMISSIONER AHEARNE:
--Auxilliary Building.
When you get up to 155, is that a stack measurement?
MR. STELLO:
Those were actual measurements No, those were in the building itself.
Those are samples.
COMMISSIONER AHEARNE: But it is not a near sample, it is not a continuous reading instrument?
MR. STELLO:
They have continuous reading, but as I understand it, the numbers were derived from actual grap samples, the number I just gave you, at about MPC was a grab sample right in the stack.
The duration of the event now, was on the order of an hour to three hours.
To give you, then, the feel for these numbers, that would be equivalent to 3 divided by 8,000 times part 20, or on the order of a thousandth or less ---
COMMISSIONER GILINSKY:
8,000 being the number of hours in a year.
MR. STELLO:
Yes, 8,000 being the number of hours in a year.
COMMISSIONER GILINSKY:
Approximately.
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So it was a very, :~very sma11.**.amount of activity that left the stack, and if we calculate what actually went into the environment, it was a very small amount and there is no'.:health hazard that we feel resulted from the event.
COMMISSIONER AHEARNE: Would you repeat again how it got into the Auxilliary Building?
MR. STELLO:
Okay.
Let me have the next slide.
(Slide)
The answer to your question is:
I don't know.
There are several possibilities that are still being
&ooked at, and I can't get the answer as to what was the source.
This is a slide that shows the chemical and volume control system, and you will notice on the volume control tank, or make-up tank as it is called in some cases, there are relief valves on it.
The~e was an awful lot of water being handled in the system, so the level of the make~~p tank could have risen and it is possible that~a relief valve could have opened.
It is possible, in the way in which they were transferring water godmgO::f.rom the emergency systems back to the normal chemical and volume control system, that there was an excess of water in the let-down system,
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- 22 23 24 25 12 and it could have been a relief valve in that system.
It is possible that the waste gase compressor, trying to take a load of gas, that it too, 9ould have developed a problem and it would have been from there.
The exact answer is that I don't know.
There is no longer any problem, and now what they are trying to do is establish exactly where it came from.
COMMISSIONER AHEARNE: When did they get back into the Aux Building?
MR. STELLO:
They had :fuimi ted access to the Aux Building, as I.understand it, th~y had a precautionary evacuation on the order of an hour, and thereafter, allowed limited access with the neeessary protective measures.
It has been confirmed that.the radioactive material in there, from the grap~:.samp*1es:~; principally noble gases.
The plant is now proceeding to a COilid shutdown.
It had been at hot standby, and when I spoke to Mr.
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I think they are about ready to go into refuelling.
They were already coasting down the plant, and they are not to start up until both he has had a chance to look at it and he is satisfied, and then we have a chance to be persuaded we are satisfied
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And I think they might go right into the refuelling outage, but I don't know that.
COMMISSIONER AHEARNE: And that was scheduled for when?
MR. STELLO:
They were in the coast-down now.
It is within a matter of a week or so.
COMMISSIONER KENNEDY:
The PN said October 5th.
Could we go back to the storage tank question and -- your PN of mid-day, approximately, indicated that during the system restoration, the operator failed to realign the suction of a-charging from the refuelling water storage tank to the volume control tank, and as a result, the control tank's pressure increased and a relief valve opened, and the implication was that this may have been the source of the release into the Aux Building. And you are saying ---
MR. STELLO:
And I'm backing away from that, because when I asked the specific question: Do we now know that that is what the source was?
The answer I'm getting back i~ that could be, but they are also looking at several others, and I didn't want to give an incorrect answer ---
COMMISSIONER KENNEDY:
That's what I wanted to confirm.
You are no longer sticking with the statement.
MR. STELLO:
Yes.
Okay, now, let me turn ---
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. 14 15 16 17 18 19 20 21 22 23 24 25 14 COMMISSIONER GILINSKY:
Could I just take you back one minute to the measurement in the stack.
These are measurements which are made by taking samples of air sort of periodically but not continually?
MR. STELLO:
They have continuous monitors on the stack, as well.
Now, I didn't get the numbers of what the monitors did read, but they have continuous monitors.
COMMISSIONER GILINSKY: So there is a continuous record of what went up~that stack?
MR. STELLO:
I didn't ask the question. I will ask the question.
I will find out.
COMMISSIONER GILINSKY:
Okay.
MR. STELLO:
I was more interested on the composition of the gases, to understand what the MPC values were, to know whether they were, in fact, pr;i.ncipally noble gases,:wnich is what you expect, and that, indeed, is what they are.
Now, I didn't pursue that because of the timeli:n:ess of getting down here, and when our people are there, we will definitely have an answer to that question.
Let me go back to the way in which we were notified, the second part of your question.
COMMISSIONER GILINSKY:
Okay.
I hope you will tell -us just a little more about what the NRC people are
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Yes.
COMMISSIONER GILINSKY:
- Fine.
MR. STELLO:
I will conclude with what NRC will be doing.
COMMISSIONER GILINSKY: Good.
MR. STELLO: At about 6:00 o'clock or after 6:00 this morning is when the even:t began.
Our Resident Inspector was at the site by about 7: 30 this morning.
COMMISSIONER AHEARNE: Was he called to be there',,'or,_:.did he -- is that his normal 15 MR. STELLO: As I understand it, he was called.
MR. JORDAN:
That's his :regular reporting hour.
MR. STELLO:
He wasn't called, he reported I
regularly.
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- COMMISS;I:ONER KENNEDY: When was the first time that anyone associated with the NRC, was informed about I
the incident,which began at noughly 6:13, as I understand I
it.
COMMISSIONER AHEARNE:
r'.t sounds like 7:30.
MR. STELLO:
At 7:30, when the Resident I
reported -- Apparently, his norma~ work hour is 7:30, and that's when he was aware of it.
I He, in turn, called Regton II at 8:00 o'clock,
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Our system,which we have in place, the phones that are,there were not used.
We were not notified through that system.
I have read, again, the instruction which we have out, and I now can:::understand where they still, probably allow for an interpretation,:;wli.ich says if 16 you have a condition where there is a problem in a reactor for an hour, and you don't have things well under control at that time, you should let us know.
Well, the reactor event was, essentially, over in terms of what was in the reactor, but then you had things going into the Auxilliary Building.
So I take the responsibility for what we have issued as instructions.
I'm not persuaded they are as clear as they need to be, and I will commit that I will go back and think about this very carefully and try to develop some more words as to what one ought to do.
I'm beginning to wonder if eventually we are going to come to the point where the phones will need to be used whenever a reactor is tripped.
COMMISSIONER AHEARNE:
But you agree with me, as I have been trying to ---
MR. STELLO:
Yes.
I said, if that serves as an answer to your note, why I do commit to do it.
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COMMISSIONER AHEARNE:
Yes.
Good.
MR.*_.STELLO:
And we will have instructions that go out to make this very, very clear.
I guess my thinking might cause me to somewhat overreact to it now.
COMMISSIONER KENNEDY:
I had been of an impression, and I can't say where *I got this, but of an impression that each morning the person in the Incident Response Center makes a quick canvass of reactors, to be sure that all those direct lines were in operation.
MR. STELLO: That was done.
COMMISSIONER:KENNEDY:
It was done?
In other words, someone in our Incident Response Center talked to someone in that plant at 7:00 o'clock this morning?
called MR. STELLO:
I do not know the exact hour.
COMMISSIONER KENNEDY:
Or approximately?
MR. STELLO:
That's true. Every plant is COMMISSIONER GILINSKY:
Every day?
MR. STELLO:
Every day.
COMMISSIONER KENNEDY:
Okay, now, so someone from our Incident Response Center was in contact with somebody in that plant at 7:00 o'clock this morning, some 45 minutes after the incident had initiated.
Is that correct?
COMMISSIONER AHEARNE:
I don't think he's sure
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COMMISSIONER KENNEDY: Well, approximately.
MR::STELLO: They were definitely contacted.
18 Our routine is to do it in the wee hours of the morning.
Now, I do not know if that was at 7:00 o'clock or at 6:00 o'clock, but they were contacted.
The response that I got back is --.: that :we Mere.* -- that when that fellow made the call, he was told there was a reactor trip, but nothing else.
Just that the reactor had tripped.
It was not being reported to him that there was a reactor trip.
That's part of his routine call to ask:.
"What's the status of the plant"?
And he was told that it had tripped, and as I understand it, that's all we had, but I do not know the time.
I can't speak to that.
COMMISSIONER KENNEQY:
It will be on his log, though?
MR. STELLO:
It will definitely be on his log, and we will know what.hour that was.
COMMISSIONER KENNEDY: And could you inform.
me, please?
MR. STELLO:
I will, indeed, do*:.that.
COMMISSIONER GILINSKY: It seems to me, that even if the instructions were not absolutely precise, and even if they didn't cover every conceivable
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And if they get above normal readings in part of the reactor tha t-_:a:te -sufficierif.:' to "require the personnel to leave, it strikes me that that crosses a threshold.
COMMISSIONER AHEARNE: When did they declare the limited access, or whatever term you used?
19 MR. STELLO:
I'll give you an approximate time.
It was in the neighborhood of 6:30 or 7:00 o'clock.
The exact time, I don't know, but of that order.
COMMISSIONER KENNEDY:
So it is conceivable that this could have occurred before that telephone contact?
MR.* STELLO:
It could have, that's right.
I want to make clear, we were COMMISSIONER KENNEDY:
I want to be sure of this.
I'd like to be sure that we nail that down, pEecisely what time this occurred, and the relative times, that is, the time this telephone call occurred, and the times in which these other events occurred.
MR. STELLO:
I will do that, and I will make sure that you are notified.
COMMISSIONER KENNEDY: Because there may be some misunderstanding about what people think are significant matters.
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Might I just add that I asked Mr. Stello this afternoon via memo,*:~and* I'm sending a copy of that down to you, for a complete run-down, a chronology on how this information was handled, the chronology of events, and so forth.
20 COMMISSIONER GILINSKY:
Yes, I *.think that's good.
MR. GOSSICK:
And also, our obligation to that line, do we need to revise that in light of the events.
COMMISSIONER AHEARNE: Well, that's what I have been trying to do for several months.
COMMISSIONER GILINSKY: Could we briefly continue and run through the rest of it, and how it went up our own system?
MR. STELLO:
Okay.
Region II was called both at 8:00 and 9:00 o'clock, the 9:00 o'clock was an update of what was going on COMMISSIONER KENNEDY: That's by our inspectors at the plant?
MR. STELLO:
Our inspectors at the plant.
We were notified here in Washin~ton, initially 10:30 ~- 11:45 ---
COMMISSIONER KENNEDY: Excuse me.
Region II was aware at 8:00 o'clock, and we,were first notified at the Incident Response Center or Headquarters, at 10:30?
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. 14 15 16 17 18 19 20 21 22 23 24 25 MR. STELLO: At Headquarters, not the Incident Response Center.
21 COMMISSIONER KENNEDY: Right, 10: 30*~ Headquarters?
MR. STELLO:
Mr. Jordan, who is sitting next to me, was notified at about 12:00 and atcabout 12:15 I was notified, then there was a series of calls made to Commissioners and their assistants, following that, through the afternoon, initially, and then periodically updating through the afternoon.
I won't go through the details of all of those.
There were several calls made to each of:. *.the Commissioners 1/:,off :i'.ces.
we, of course, notified Mr. Gossick, and we talked.
I have made::certain~_and assured myself that the State of Virginia was, indeed.,: :.notified, and also called and made sure that someone in the Governor's office was aware of this.
COMMISSIONER KENNEDY: What time was the State of Virginia notified?
MR. JORDAN:
Before 11:30.
MR. STELLO:
About 11:00-11:30.
They were notified by the Region, and I also spoke to someone from the office this afternoon myself.
COMMISSIONER KENNEDY: The licensee did not notify the State?
MR. STELLO:
My understanding is that after I
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MR. CASE:
In the Governor's office.
22 MR. STELLO:
In the Governor's office.
I do not know for certain they did or didn't notify or discuss this with tne: :State prior to that.
COMMISSIONER AHEARNE:
Could you assess the health and safety significance of this?
MR. STELLO:
Based on what I have right now, I don't see any significant health and safety issue, whatsoever.
As: L.ind+/-cated.,earlier, it is an extremely small fraction of part 20, because the total duration of the release was very, very small.
COMMISSIONER BRADFORD: Were there any worker exposures?
MR. STELLO:
I don't know the answer to that.
That's part of what we want to get into, what we will be looking at:; today, what our inspectors are going to
,,be doing and are doing now.
I don't have any information :tha t.-:there are any, it is just that I don't want to say there aren't without time to go through and check.
I COMMISSIONER AHEARNE:
But as far as what you
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- 14 15 16 17 18 19 20 21 22 23 24 25 23 have at the present time, you know of no health and safety significance of the MR. STELLO:
From the public point of view, that's the thrust of your question?
COMMISSIONER AHEARNE: Yes.
MR. STELLO:
And the answer to that is I don't see any.
With respect.to what went on in-plant, we are looking at that.
That's a different question.
I could make some judgments now, but I prefer to reserve until we have had a chance to get COMMISSIONER GILINSKY:
In any case, you will prepare a detailed chronology.of the notification, steps that were taken, and the:way the*communication system functioned?
MR. STELLO:
Yes.
COMMISSIONER AHEARNE: And the reactor is on --
at the moment on its way to cold shu,tdown, or?
MR. STELLO:
The reactor is being taken to a cold shutdown, *.and there,~is a cooldown rate specified which we have asked them to follow, and go to a normal cold shutdown.
It is typically 7 or 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> before it woul be in that condition.
COMMISSIONER GILINSKY: ~ould you tell us what NRC is doing?
MR. STELLO:
Yes.
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9 10 11 12 13 15 16 17 18 19 20 21 22 23 24 25 24 We have two inspectors who, as I have already indicated, have been on site and are continuing to follow what is going on.
There are two health physicists who already should be at the site, who will be looking at some of*.. the questions that have*,_been raised here, in terms of worker exposures, the actual strip charts in terms of what quality the monitors did during the course of the event, doing any surveys that are needed.
And they should already be at the plant and started.
I have sent Mr. Moseley, who works for me as a division director, to be our spokesman at the site, and to monitor and to be in charge of the activities that will go on at the site.
Dr. Ross has::*also gone down with specialists in the area of understanding the transient that happened in the plant, to review the records and understand its significance.
COMMISSIONER KENNEDY: This is Dr. Ross from NRC -- I mean NRR?
MR. STELLO:
Yes.
He has taken four-*addi tional people down with him.
The expectation is *:that th~y will have been there by about 6:00 o'clock, just about now.
When I get back to Bethesda, I will expect to get briefed and see what the status of their activities has been, and I'm hoping that by this evening we will have
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I won't have that worked out until some tine tomorrow..
COMMISSIONER:KENNEDY:
Did you say that the licensee has agreed that he will retain his -- the plant in cold shutdown until further discussion?
MR. STELLO:
That's correct.
COMMISSIONER BRADFORD: The amounts of radiation involved, do they give you any concern about the fuel damage?
MR. STELLO:
No. The isotopes are.principally nobel gases that are associated with a normal operation.
There are not unusual quantities, and we are not seeing any increase in the radiation,* but that is clearly an issue that will be examined very carefully primary core samples.
But based on information we have in terms of the temperatures in the system, I would say it would be very unlikely that there should be any concern, because they were sub-cooled, highly sub-cooled, so there shouldn't have been any voids 6f the system; but that will be checked out thoroughly to.substantiate that that's, indeed, the case.
COMMISSIONER GILINSKY: Peter?
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9 10 11 12 13 15 16 17 18 19 20 21 22 23 24 25 26 COMMISSIONER BRADFORD: What does the word "sub-cooled" mean?
MR. STELLO:
It is the amount that the water is cooled in temperature below the saturation temperature, that:'.is:;. *the,temperature-.::in which the steam is formed from the water.
Water at* 180 degrees atmospheric pressure.....
was 32 degrees sub-cooled.
COMMISSIONER GILINSKY:
Sub-cooled is good.
COMMISSIONER BRADFORD: It just doesn't appear in the Constitution.
COMMISSIONER GILINSKY: Very well.
You will keep us informed of things as they develop, and of anything significant that you find out.
MR. STELLO:
Yes.
COMMISSIONER GILINSKY: Very well, and we will be looking forward to this chronology.
Thank you very much.
(Whereupon, the meeting in the above-matter was concluded at 6:04 p.m.)
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