ML19199A227
| ML19199A227 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 04/03/1979 |
| From: | Harold Denton Office of Nuclear Reactor Regulation |
| To: | |
| References | |
| NUDOCS 7904050199 | |
| Download: ML19199A227 (27) | |
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UNITED STATES OF AMERICA 2 l!
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NUCLEAR REGULATORY COMMISSION 3-i l
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PRESS CONFERENCE 10 !
ON 33 THREE MILE ISLAND 12 13 l 1
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' Middletown, Pennsylvania April 3, 1979
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1 2
PROCEEDINGS i
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MR. DENTON:
What I'd like to do is give a quick I
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status on the situation at the reactor as of about noontime i
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5 and touch on a few other issues and then go to questions.
6 The situation remains stable.
The core pressure is.,
7 1100 psi.
The temperaturc has remained at 281 degrees.
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The hydroger. concentration in the containment is 2.1 i'
percent.
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The containment building remains subatmospheric, about a 10 pound psi negative.
The containment temperature is 88 t
II degrees.
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probably the most significant development regarding 13 the hydrogen bubble and the explosion of hydrogen:
today a
14 I want to report that we no longer consider hydrogen explosion Y
15 I at a significant problem at this plant for three reasons; 16 the fact that the question of oxygen evolution in this 9'
17 j' containment in this type of atmosphere has been resolved and i'
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the numbers we were using before were too conservative; the I
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bubble has been climinated, for all practical purposes.
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There's prvbably still some small bubbles in the 21 '
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containment, but they're not -- they're not the type up at 22 the top of the dome, and they pose no further significant 23 safety problems.
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And the recombine-is working and removing hydrogen extiers. inc. g 2S l from the containment.
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The power being produced by the core at this t
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time after the accident is a little less than six megawatts, 4
which is about.18 percent of the total amount of heat that l
5 was produced before.
6 g
A few elements still remain above the 400 degree 7
temperature, but none are above the saturation temperature 8
for the pressure which the system maintains.
I 9 i There have been -- there has been a new development,
f 10 regarding the types of radionuclides found in the enviNnment.
II I think I previously reported that only kryptons and xenons 12 have been found, but there is now evidence that radiolodines t
13 are found in very small amounts in some milk samples.
t 14 We've brought up some people from the FDA this 15 l morning and talked to them; the levels appear to be, when 16 they are found, on the order of 10 to 20 picoeuries per i
17l liter.
These aro very small levels.
They are not a lot i
18 different than our own Appendix I levels that we would permit l9 I in continuous consumption of milk for a year.
l 201 There's also been some iodine and cobalt found 21 in the industrial waste water that's been released from the O
@2 h plant.
At our request, the licensee and the state's request T"i h I
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the licensco ceased discharging this water last night.
j 4
So when we make some further analyses, I expect that the a m eices.in..
25 I plant will be allowed to continue this discharge this water
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I RAW TRANSCRIPT - UNCORRECTED in accordance with the conditions of its license.
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I think that's about a quick summary of it.
QUESTION:
Have you found out why a leak occurred l
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shortly after midnight last night in the hydrogen containment 6l area during the hydrogen sampling process, the monitoring 7
process?
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MR. DENTON:
I'm not familiar with that; couldyoul 9
tell me a little bit more about it.
10 '
QUESTION:
Yes.
Last night outside the plant, II two reporters fromthe Philadelphia Inquirer monitored the 12 radio conversations betwcon a fellow named Tom Frailer (PHONETIb) 13 and a fellow named Vic in the plant control room.
i 14 Tom says, there'sadirectleakfromthecontainmenth 15 Shut the damn thing down and quit screwing around. Shut the 16 release.
Shut all the valves of the monitor.
We're going to 17 take samples and find out what caused this.
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18..
Then Tom gets on the radio to the mobile radiation l.
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detection unit and dispatches them to an area south of the l
20 Three Mile Island Plant.
t 21 He asks them to take the highest reading that they i
i 22 get at tho'se sites I
23 ;l 1l Vic responds, I'm checking on the status of
,J iriot 1solat. ton.
n.wam.sne.l t
25 Tom says, see if you can determino by sampling i
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l in the system where the leak actually occurred.
Where in the 1 3 !
valves --
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4 MR. DENTON:
Well, maybe I can -- with that i
5 much background, maybe I can answer.
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6, In trying to take samples of -- in either the j
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7 waste gas storage tanks, in trying to take any samples of I
8 l primary coolant or any other sample, the -- we've had trouble i
9 taking these samples without introducing leaks.
10 '
We have one sample frem the waste gas storage I
11 tank that shows 50 percent -- 56 percent hydrogen.
The rest 12 is nitrogen.
We decided to take a second sample; that 13 second sanple showed entirely different composition, indicati,ng 14 l air in contamination in the sample.
And when these types of 15 samples are taken ~~ it's difficult to take a sample without 16 having a leak somewhere within the sampling point and back l
17 to the tank.
The total amount of radioactivity getting out I
18 aren't changing the off-site dosage significantly.
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nortete Inc.
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6 1
I QUESTION:
First, can you possibly elaborate a 2
little bit more on the s itua tion of iodi,ne?
We've asked ll 3 jl about it several times and thus far you haven't had a good d
deal of information.
5 Where is the iodine specifically being tested; I
6 where are the samples being taken from?
I couldn't understandj I
7 for example, the term you used to describe the amount of 8
iodine, the offect on the milk, grass, and farmers, the
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9 iodine in the water, what that would effect.
10 '
Second of all, I'm sure you're aware -- I'd like l
II a littic bit of the truth:
There was a situation at the 12 University of Southern Maine, a Dr. Armand Shroud happened 13 to have been looking at a meter up at his laboratory.
There 14 was a rai rstorm and the meter measured 100 times the normal 15 amount of radioactivity, he said, in the area.
16 Now he suggested that it perhaps is coming from 17 Harrisburg.
I understand since then that this is perhaps not i
18 the case.
l.
I9 But the question is:
howmuchradioacth.vity 20 might have traveled around the area?
In it possible it could ',
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I 21 have gotten there from wind streams, et cetera?
t 22 MR. DENTOM:
Let me try to elaborate on that a 23 bit.
I 24 f The samples that were taken by the NRC when we n w m.n.:.,
j 25 [
first arrived were sort of emergency type samples.
We sampled '
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1 air, milk, water, and had those done with our mobile lounge.
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And in fact, the NRC d
samples have yet failed to find any 3[
iodine levels above detectable levels even in milk.
I 4'
I think we sampled 56 milk samples from 17 differ- *
,5 i
ent farms.
Now the FDA in its milk sampling program of somo-6l what wider scope, and they're sending them off to a laboratory 7
in Massachusetts for analysis, originally reported some B
samples as high as 41 picoeuries in milk at some nearby farms.,
9 QUESTION:
What's that?
10 !
MR. DENTON:
Picocuries per liter.
II They've since refined their numbers.
I understand 12 the peak sample that is now reported by FDA is about 31 pico-13 curies per liter.
The range of activity in those samples that Id they considered liable is on the order of 10 to 20 picoeuries D:
per liter.
l 16 If you were to consume milk like that for a month, i
17 the radiation level would be approximately the same as would IB be permitted under our limits for routino operations.
I I9 ?
Maybe I stated that poorly, but I don't consider l
20 these radiation levels of 10 to 20 picocuries per liter any 21 cause for alarm with regard to milk.,
11'~161 i
b 22 'l Now the question, where is this iodine coming i
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from, we've been able to go back and look at the cartridges 74 !l that sample the air as it's released from the plant.
All the x, wn. sve.
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air relcased from the plant goes through a high efficiency h
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I particulate filter and then through a charcol filter before l
2l it's released.
The air then is sampled by passing it through 3
a charcol cartridge, and these cartridges are counted.
l 4
Our best estimato of the total amount of iodine 5:
tnat has been released as a result of this accident is about i
6 one curie..
i 7
OUESTION:
Would you compare these concentrations 8
to the maximum permissible concentration that one might get 9
8 from, say, the Chinese fallout?
b 10 I; MR. DENTON:
The governor put out a press release II earlier today that I agree with.
He pointed out that the FDA 12 i
action level is 12,000 picoeuries per liter.
And during the 13 Chinese fallout period levels of 100 picoeuries, and in some 14h instances up to 300 picoeuries, were reached.
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15 Our own standards call 'for not exceeding about 16 two and a half picocuries per liter on an annual basis for 17 f milk consumed during the whole year.
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QUESTION:
Dr. Denton, when will this all be over?
19 When can the pregnant women and children, and life get back 20 to normal in this arca?
21 l MR. DENTON:
I hope that from here on out we can id 22 i!
move rapidly in that direction, with the fact that we're no i
i 23 ;l i
longer concerned about a hydrogen explosion and the bubble
~
i 24 jr-. 1:r nb "iwped-iwent to operation.
C ro right now developing nextieri, tre. :1 25 and looking at plans for the most offective way to bring the l
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4 reactor to a cold shutdown state without an increased leakage 2
from the plant.
I'm not yet ready to give a prediction.
i i.
The Staff is looking at it.
But I'm hopeful' we ii 4f can now move forward, as we've eliminated these problems.
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QUESTION:
Mr. Denton, aren't there daughter 6
products of krypton and xenon that include iodine-131 and 7'
strontium-9 0 that would start to be detected a few days from 8
now?
9 MR. DENTON:
There are daughter products of xenon i.
10 'I and klypton, but iodine is not one of them.
Strontium is.
II And I believe that the radioisotope most commonly found is 12 l rubidium-88, where they have very short half-lives, and the 13 ones that have long half-lives, like strontium, are found in Id oxceedingly small amounts when they are generated by shorter-4 15 lived parents.
16 l QUESTIOM:
Are you Icoking for strontium which l
'I7 obviously in a --
I8 MR. DENTON:
Yes, we are, f
19?
QUESTION:
A follow-up on an earlier question.
20 l Again in layman's terms, now, you are telling us t
2I that the bubblo danger is gone.
As you described it, what is 22 !
the basic danger, then, that remains?
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23 l MR. DENTON:
I think, as 7 said before, time is on i
2d our side.
Of course, temperatures are getting lower, the amount Hextrees, Inc,1 1
25 '
encrated b, el is lowcr.
As lon as the s sten 5
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l 1 l RAW TRANSCRIPT - UNCORREC'.c.D s
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I is pressurized there is a potential that'some loss of cooling k
3 mechanism might still cause the core to become uncovered, 4
until we can get the system operating in a state such as 5
it's operating with water below the boiling point so that we 6
don't have to worry with system failures.
7 QUESTION:
Until you do that, the danger remains?
8 MR. DENTON:
I think the danger point is consider-l 9
ably down from where it was a few days ago because of the 10 concerns about the bubble e.nd hydrogen explosion.
II So in my own view, it's
- we can fall back on 12 the traditional options for bringing the reactor core to a 13 cold condition.
And the main obstacle to doing so is to Id pick one which doesn't do further fuel damage and which 15.,
doesn' t result in the release of the highly radioactive i
16!
water inside the containment to the environment.
17 I
QUESTION:
Would you describe whether or not l
h 18 f there has been any radioactivity detected in the water supplies?
N"f And also would you go into the (inaudible) potassium iodine 20 f and whether or not that's under consideration for workers and 21 other people that might be subjected to the iodine?
22 MR. DENTON:
I don' t have the data at hand on 23,i whether or not radioactivity in water has been found at other W
2 cities.
I kind of doubt it.
Because the plant has essentially Hextrer s. Inc.
I 25 l been releasing radioactivity at or near, slightly above or
11 i
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b6 1 I slightly below our normal limits for releases.
And at those i
2 levels I would not expect radioactivity to be found in down-i
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stream water supplies.
I 4l With regard to iodine blocking tablets, I under-5 stand that this is being considered by people within HEW mere-lws 6.
ly as a precautionary measure.
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QUESTION:
Dr. Denton, yesterday you expressed 2
come concern ab'et the effect of high radioactivity on the 11
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instruments and.sbles within the containment.
i 4
Could you tell us today what is the state of that 5
and what is the short term scenario for that?
MR. DENTON:
Well, during the accident, if I 7
go back to time zero, there were a few instrument losses at 0
that time.
There were no further changes in the status of 9
the instrumentation until a loss of the flow transmitter 10 which I described yesterday.
There's been no further changes 11 in the status of instrumentation.
Most of the instrumentation at the plant is redundant and we have a means to get the information we are 14 je seeking, but we do have a task force looking ahead and-15 lll making contingency plans if we do lom vital instrumentation.
i I
16 I l
QUESTION:
Dr. Denton, could you tell us first 17 how much the temperature in the core has been brought down 1
[
in the last 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />; and second, could you tell us what 19 $t the problems, the risks are involved in bringing the RHR.
20,
i system into operation and whether you have tested it for i
21 'b-C) operation for possible leakage.
I C1
,TT MR. DENTON:
The whole effort over the past few h423 l C
eq l
days has been to maintain the core in a stable condition, l
N; so the temperature of the inlet and outlet of the core has t
no mm,wim.
25 f! been essentially 280 degrees for the past neveral days.
We
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RAW TRANSCRIPT - UNCORRECTED 12 I
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deliberately tried not to change the known collable 3
geometry of the core, the known cooling system; so there's 4j boon no change in the method of cooling.
With regard to the 8
3 RHR system, we want to be sure before we turn it on that l
1 6
~
we've taken every precaution against leaks and ensure maintainability.
e 8
The auxiliary building was contaminated because of 9
the water on the floor as a result of earlier spills;
.there 10 was a radiation survey made yesterday by a team from the II Department of Energy to see what the problems would be when 12 we go in and try to put in shielding between the redundant I3 components.
We want to put in filters on components t' hat N'
.might leak.
Since the RHR brings contaminated water from t
"f the containment out and cools it and returns it, it's very 16 't critical that we don't turn it on until we have all the I?
leaks or potential leaks in that system isolated and be sure 18!
the system would perform adequately for the type of conditions j
i I9 [h we've got.
20 l QUESTION:
Yes, Mr. Denton, can you please tell us --
?
21 h can ya2 confirm whether the core is totally damaged;
- second, I
22 whether any nuclear fission is going on in the core at the l
23 li l
present time; and third, whether this plant -- how long will il 11 190 3'
i it take to decontaminate the plant.
R e w r rer s, I r*C.
I 25 MR. DSNTON:
Well, with regard to the fission li
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2 process, that was terminated by the control rods -- by l
scram at the initiation the event.
MR. FOUCHARD:
Repeat your second two questions, f.
4 5
OUESTION:
The second part:
is the core totally.
l
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6l damaged, even greater than the estimate you gave us?
Is there 7
some further damagc?
I B
MR. DENTON:
I haven't given you any new numbers i
9 aside from the numbers I gave you earlier.
I said that 10 '
when we look at the core -- that there will be extensive II I
damage to most of the fuel rods, the upper part of the cladding 12 of those rods.
I3 I should expect perforations in the cladding, I '*
fragmentation in the pellets; and you've got approximately 15 lI 2 to 15 percent of the core which had experienced very 16 j high temperatures as a result of transient.
I7 f I would expect that the upper part of the core IB,
would show extensive damage.
I 19 '.
QUESTION:
With school scheduled to open on a l
t 20 l large scale tomorrow, are you telling the people are here that 1
i 21f the chances for any type of massive evacuation are totally 22 )
remote?
I 23'I MR. DENTON:
I think that's a decisica that's nade I:
d 11~191 24 a by the governor.
I would defer to his judgment.
a..u,... uc. i 25 h QUESTION:
What would you advise him at this point,
15 RAW TRANSCRIPT - UNCORRECTED l
1 based on what you said about the bubble?
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MR. DENTON:
There are two issues on which I d'
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reported to the governor when I talked to him last night.
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4 t
I reported to him on the progress of b;ing able to pump g
i 5
i back into the containment the leakage that still is occurri'ng I
6 i
from the letdown system.
We're still checking that system j
7 out.
We've not yet begun to pump that leakage back into the containment, and that's a source of routine, low level O
9 exposure.
10 :
Then there's the question of the core itself.
And 11 with regard to the core itself, I'm very optimistic now 12 that we've gotten over certain hurdles to bring in down; I
13 u
think we're very close to being able to pump back into the 14 l
containment the gases that have been generated outside of the auxiliary building.
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QUE STION:
With the hydrogen bubble diminished
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and the buildup of oxygen problem gone, when "ou do nake. the i
4 deliberate attempt to brir.g the reactor down, at this point S
would you recommend any necessity for evacuation?
i 6
MR. DENTON:
It depends on the mode selected.
I I
7 think it's likely that we will attempt to cool the plant down 8
using exactly the same mode of cooling as it's now operated l
9 in because we don't have the worry with bubble expansion that 10 1 was our principal concern earlier.
II QUESTION:
Are you talking about days or weeks to I2l shut down?
l I3 MR. DENTON:
I believe -- I ccn give you a' much I
I4 'j better handle on it tonight.
I need to look at the outcome--
l' 15 QUESTION:
W lat about y' sterday?
e i
16 i
MR. DENTON:
Yesterday we were still worried about 1
17 I
the bubble.
And now that we've passed that hurdle, our 18 concerns will be better framed.
I WI QUESTION:
You've answered two of the questions 3
20 [
that have been posed earlier, that is:
how does radiation 21 travel long distances.
And the second question is:
Based o
I i
22 on your estimates of decontamination used (inaudible), how I
23 1 lf long you expect it will be before work can begin in the 117 Da 24 !
Rex rtett, Inc. [
25 MR. DENTON:
The question is, how is radiation l'
.17 1
1 RAW TRANSCRIPT - UNCORRECTED 2
2 transported, and secondly, how long before workers can enter 2l the containment.
t 4
I discount completely any influence of this plant 5
on samples in Maine.
In other words, I don't think even with i
6,1 the one curie release that has occurred over the last several 7
days that there has been any analytical equip.aent which could 8
detect iodine concentrations beyond ten miles or that sort of 9
distance.
l t
10 '
With regard to how long before entering the Il containment, the half-life of 1e principal isotope, xenon, 12 '
is five days.
And the radioactive levels continue to be very I3 high in the dome.
'So we will continue to wait for decay to I4 take place and those levels to get down so that people can ll 15 ;!
enter.
16 It could be four or five half-lives before the i
i 17 j xenon levels are down to a level, i
18 I might mention also that the dome reading continues U!
-to be somewhat synonomous with other levels in the containment,'
l 20 l which are lower.
So it's not clear that the radiation levels i
2I t iroughou t the containment are uniform.
I 22 i
QUESTION:
Can the problem be totally cleaned up? '.
23 Can the plant operator get in?
If so, how long might that 11'~194 24 whole operation take?
m we rm, inc.
25f MR. DENTON:
That's another one that our think tank
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n 9
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RAW TRANSCRIPT - UNCORRECTED b3 i
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is scoping out.
Obviously it would require refueling of 2
the core.
That will require looking at all the instrument t
dI cables and instrumentation which has been exposed to these 5
high radiation levels to assure they could still work.
6' I think we're talking about a considerable period 7
of time before the plant would resume operation.
8 l QUESTION:
Is it certain that it can, or in there 9
a possibility that it can't resume at all.
I 10 MR. DENTON:
I think it's really too early to say, My best estimate would be that it's likely the plant could be 11 12 restored to an adequate status to resume operation.
But we 13 have to defer on that until we've actually looked inside to 1
Mj see how much equip ent has been damaged.
It 15 8 QUESTION:
Mr. Denton, is there a significant I
16 probability that the level of risk, say on Saturday, would 17 )i increase once again in the process of bringing the reactor to I
18 I cold shutdown?
T9 y ' " "
MR. DEt4 tut 4!""1 d5ui3t it. ' ' I ilitrrh-tiridt Tna concGi.it
~~
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20 we had with the bubble was it interf ered with the normal proven i
21 i; ways of cooling.
The hydrogen brought with it a chance for 1/3 h
Q22 i complete disruption of the coolant system due to an explosion, vi l!
l, 23 With those potentials out of the way, I expect i
I Td '/4 y there to continue to be frustrating problems, that the equip-
,91 S t >0f f Pf t IDC. l 25,
ment may fall. Dut with each day that goes by, the core gets r
.19 I
I RAW TPASSCRIPT - UNCORRECTED 7 lll cooler.
And without the bubble in the core there are Inany Iws 3 'I systems available to cope with bringing it down.
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1 3
i OUESTION:
What effect really does rain have on 2:
1 h
the radioactivity.
3 '(
l l
MR. DENTON:
If there are particulates in the 4
l ntmosphere such as iodine -- in other words, they would l
5 I
I scavenge out of the atmosphere, the releases, and tend 6l i
to concentrate them in the area of the site.
7 i
With regards to the nobic gases, they're probably 8
I more dependent on wind speed than on rainfall.
9 QUESTION:
Could you go through the -- what the 10 '
I major means were for'etting rid of the hydrogen bubble, and g
i 11 l
did it proceed as you have been outlining your options over 12 i'
the last few days?
33 i I mean, did it go away the way you expected it to 14
(
go away, or did it go away in a way~that surprised you?
MR. DENTON:
I think it was a little bit because of 16 :
- P.
our actions and maybe a little bit of serendipity.
17 '
l QUESTION:
Excuse me, I didn't hear that.
18 MR. DENTON:
A little bit of luck and a little bit 176 of forethought I think it responsible for it.
20 [
j Several days ago we decided that it was very important fkl1 I
l that we do everything that we could to lower the hydrogen concentration above the vessel; so this is when we asked the
- 1>9 j
applicant to continue spraying coolant in the pressurizer and 24 continue getting it down.
Since that time we've discovered 25j
I, 21
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ji several other mechanisms that we're operating, such as 2!!
'i 3 h control rod leakage, pump seal leakage, the letdown system, i
and perhaps the chemical recombination of the hydrogen and i
4 e
i oxygen within the water itself, using radiolysis and the 5
I back pressure.
6; l
So all these combinations of events have caused a reduction.
I would say that there is no bubble any longer 3
i at the top of the core.
There are probably small bubbles 9
1' throughout the water, and the water has a certain amount of 10 '
I sponginess to it.
11 But there's no longer the bubble at the top that 17 was our previous concern.
i QUESTION:
And no --
14 I
MR. FOUCHARD:
Just a minute.
The background 15 noisc in the rear is -- we're having a great difficulty 16 hearing your questions.
Could we please just keep it a j
little more quiet.
18 i QUESTION:
Dr. Denton, was there -- do you have 19 1 i
any evidence that there was trouble at the reactor prior to 20 !
4:00 a.m.
last Wednesday when Met Edison claims it began?
21 l
n Il MR. DENTON:
I have no more civdence than was 23 'l described in the bulletin that was released yesterday to all the other applicants.
11~Ibb 24 ii ex,re... ru. h They were having roblems with the fe dwater
RAW TRANSCRIPT UNCORRECTED 22 hi l
l, and looking back, these were the types of startup problems.
2p And with hindsight I think we recognize that there were l
l t
0 come problems with the auxiliary system.
3 l
l 4'
QUESTION:
We've heard various reports since the 3
beginning of how much water was actually in the containment; 6
perhaps a quarter of a million gallons or more.
If that l
i 7
is as highly contaminated as the atnosphere in the e
8;.
containment, what do you do with a quarter of a million l
9 gallons of contaminated water?
i 10 '
MR. DENTON:
It would have to be processed through 11 the rad waste treatment system, and the particular radioactivity 12 solidified; in regard to the gases, we'll just have to wait i
~
13; for decay to take place in the system.
14 QUESTION:
It will bc transported?
15 MR. DENTON:
No, the water would be cleaned up and I.
16 purified before it.would be released.
H I
17 QUESTION:
Was there a tape recording made -- was i
18 b a tape recorder running in the control center at the time 19 l of the incident last Wednesday?
i l
20 i MR. DENTON:
A tape recorder?
21 QUESTION:
Was a tape recorder as a normal l
22,
precautionary measure to monitor something in case an 1
1 it-1119 i
23 l accident occurred --
e i
2/. l!
MR. DENTON:
We have no requirement for vocal s'
escriert, fnc. jl tape recorders running 25 l If there were, it was not -- not a o
l 23 I
i RAW TRANSCRIPT - UNCORRECTED i
2 requirement.
I
- i QUECTION:
You said yest erday that once the
- l l
1 I
hydrogen bubble was gone there would be no hydraulic l
5 obstacles to cooldown.
Are there any other kinds of i
)
0 obstacles to cooldown, other that, the possibility of l
I some leakage that you've outlined?
i 8
MR. DENTON:
No.
With the bubble gone, the only hydraulic obstacle is to be sure that you don't change t
10 )
pressure drops across the core or change flow rates such that l
11 i'l you might further damage the fuel.
So, it's not an obstacle i
I2 to getting water through the system.
I3 There's no problem with the bubble causing pump Id failure or cavitation.
But we want to make sure the change N
15 in the hydraulics of the system don't further damage the 16 primary system.
I7 !
QUESTION:
To go back to your assessment of when I8 l]it might be possible to enter containment, you had mentioned I
19 li that the principal isotope there in xenon with a half life i
20 [ of about five days.
You spoke of several half lives.
Does l
21 that tr, slate into a period of approxirnately 20 to 25 days as f j
p! your bes 11'200 4
22 gue ;?
23 lj i
MR. DENTON:
I think that's even optimistic,
'l 24 becauso there are probably even iodines in the water and ex, en uc..'
25 ;I here are trace cicme t of barium and c
24 RAN TRANSCRIPT - UNCORRECTED i
I;
,i predominant isotope would be gone considerably by that time, there might still be others which.;ould take a little whilc to run off.
(
i A
t So I haven't turned to that issue and attempted 5
to get a level, but I would think it would be in excess of 6
l a month.
7 QUESTION:
In excess of a month?
8 1
MR. DENTON:
Yes.
9 OUESTION:
Just to be sure I understand something 10 :i in connection with your references to the containment building; I
when that transcript was read to you carlier that appeared to be a monitoring of two workers, you gave a rather elaborate answer; in a word, has there been any radioactive, 14 l
leak from the containment building?.
g MR. DENTON:
To my knowledge, no leakage from the 16 l containment building.
The containment appears to be 17 1 functioning exactly the way containments are supposed to be, I
isolating under negative pressure.
Leakage would occer into 19 1 i
the containment building, however,whenever samples are taken.
20 t
It is inevitable that some leakage would occur during the
[
21 l
process, and there is leakage going of noble gases and some lodines occurring from the plant now.
As water dries up from previous spills, it's continuing to let iodine into thd atmosphere, and then until we car get the waste gas 25:
,I ek into I
i.
+.
25 l
I t
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RAW TRANSCRIPT - UNCORRECTED l
t 2
the containment, everything that comes out of the containment I
I i
i 3 j!
there will continue to be small releases as manual operations' i
i d'
are performed and the system is aligned, of course, pumping f
s 5
it back.
i 6
QUESTION:
Are you going to have a talk with Tom 7
and Dick.
8 MR. DENTON:
I guess Tom and Dick work for the 9
power company.
I 10 '
QUESTION:
What are the present levels of radiation' II coming out of that plant now?
MR. DENTON:
I don't have a new number.
Yesterday l 12 13 I
I said that the radiation levels with regard to noble gases
,i Id are going down; in other words, the measurement made in the 15 plume by our helicopter shows continuous decreasing levels of 16 !
the noble gases.
i 17 The iodine levels that are coming out probably are IB just about constant or changing with a half life of that 1
I9 iodine isotope.
Staff says the best number we have for iodine' 20 4 is about a curic over the total course of the accident to date, i
21 I
22 g:
i 23 j!
li'202 24 a ncerm. tec. l 25 n y
u
26 i
Il RAW TRANSCRIPT - UNCORRECTED i
on QUESTION:
On the basis of this survey that you ol 2
3[
said was taken yesterday, can you describe those a little bit d
more fully, the contamination situation in the auxiliary t
5 building?
6 MR. DENTOti:
Earlier in the accident going back I
7 neveral days, waste tanko in the auxiliary building were 1
8 overfilled and water was en the floor of the auxiliary buildin 9
And as the water there begins to evaporate, it leaven on the I
I U'
flocr 'odines and maybe other particulato matter, the cobalts II that were)in the water.
12 And so the auxiliary building is quite hot, and I
I3 that's why the DOE team was then surveying to establis'h what 14 [
kind of decontamination would be necessary before you could 15 go in and establish the kinds of shielding and filter equip-l 16 ment in order to make it RHR operable for long term core heat I
17 l removal systems.
18 OUESTION:
Okay.
You said a little while ago that I
i 19 1!
because of your actions and a little bit of luck, the reactor l
20 l is cooling and the bubble is disappearing.
t 7I By " luck" do you mean the fact that it's raining h
i 22 ll l
and colder weather outside?
What effect does that have on the.
i i
23 building, the vessel and the problem?
I 74 MR. DENTON:
By " luck" I meant each one of these i
75 various sources had moved.
Hydrogen from the containment was i
'e
~s 27 I
}
79 I
RAW TRANSCRIPT - UNCORRECTED I
b2 l
l 2
3 really responsible --
l 1
3; QUESTION:
Was the change in the weather really I
i 4
i affecting --
l 5l MR. DENTON:
No, sir, I don't think co.
h 6j QUESTION:
Met Edison people are saying that the 3
7 change in weather moved the bubble down,
.s reduced the j
l 8
b ubb le.
9!
MR. DENTON:
I guess I'll have to get educated L
10 '
on that one.
II '
MR. FOUCHARD:
Yes, ma'am, the last question.
I 12 }
QUESTION:
When the safety injection system was 13 turned off manually, you said that you still weren't sure how I4 long it stayed off, and have you found out since?
e 15 '
MR. DENTON:
I think we've been looking at that.
I 16 'l We plan to submit a briefing on the entire incident in a few I7 l' days.
And at that time we can tell you what we know about i
I8 l the entire history of the event.
I 19 d I'm not going back to look to establish times and I
20 sequences yet; but it will be in a public meeting with the I
21 Commission.
i 22,1 MR. FOUCHARD:
Thank you very much.
r i
i i
23 (Whereupon, at 3:20 p.m.,
the press conferenco j
21 li i
was adjourned.)
n, mm...' '" i 11 204 i
25 [
1.-