ML19199A312

Transcript of 790406 Press Conference in Middletown,Pa Re TMI Incident.Pp 1-28

ML19199A312
Person / Time
Site:	Crane
Issue date:	04/06/1979
From:	Harold Denton Office of Nuclear Reactor Regulation
To:
References
NUDOCS 7904120381
Download: ML19199A312 (28)

Text

.

Sh~ ]2d cc UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION PRESS CONFERENCE ON THRCE MILE ISLAND Middletown, Pennsylvania April 6, 1979 4:00 p.m. to 4:52 p.m.

Pages 1-28 7904120 9 13 100

2 4/6/79 I

FAW TRANSCRIPT - UNCORRECTED Madelon l

2

':: pol l

PROCEEDINGS 3

FR. FOUCHARD:

Good afternoo'n, I'm sorry to 4

keep you waiting again.

5 Fr. Denton is here to give you a roundup of 6

today's activities.

He's brought with him Mr. Victor Stelko, 7

S-t-e-1-1-o, who grew up about 60 miles from here in the f

Keiser in the Pennsylvania arca.

Mr. Stollo is director of 9

the Division of Operating Reactors in the Office of Nuclear 10 Reactor Regulation.

S :), Harold, if you want to tell them what we've 12 been up to to: lay.

13 MR. DENTON.

Today was not quite as routine as I4 N

yesterday.

I 11 hit the highlights briefly and then take 15 questions eit ner on the status or plan or on the chronology 16 of the accident.

We can answer those kinds of questions.

II Let me cover first the status of our ' efforts to I8 pump back into the containment building those waste gases g

U which were in the tanks in the auxiliary building.

20 That effort started about six o' clock this morning.

2I During the effort it was found that there was a leak in the l

22 plumbing s;ystem somewhere.

This was noticed by an increase in i

23 radiation levels in the auxiliary building.

The pumping was 24 stopped; the esking was identified; the pumping started I

Aar Fecsesi Benotters. Enc.

20 againaboutnyneo' clock.

I i

13 iC1

3 i

I RAW TRANSCRIPT - UNCORRCCTED t

I I

'6/79 So thesc'. Waste gas deca 9 tanks are being pumped mob 2 2

back into the containment at a rate of about three -- a rate t

which corresponds to a decrease in hank pressure of about 3

4 three pounds an hour.

These tanks 3 tarted out at about 90 5

pounds psi, so it will tako quite a, while, maybe a day.

But 6

in essence this will pump back into the containment those "

7 noble gases which have been the cause of continuing release 8

to the environment and public expos are.

I 9

Another unusual event tbday was the tripping of the recirculation pump which is usedl 10 to

circulate water l

II from the reactor vessel to.the steain generator.

This pump 12 tripped at about 1:15 duc to a mal unction of the cooling system, from the motor.

The pump coasted down..The contingency 13 plans were followed.

The other pump in that group was started-14 l

15 This is Loop A, I believe.

So it would 'be pump 2A was up.

1 16 started for a total duration of about two minutes.

The other i'

II purp was running.

18 The status of the original pump that is now i

~

l9 functional has been restored so it.can be started again if 20 need be.

21 I guess one last item a industrial waste treat-22 This is the water that was stopped by the State ment water.

23 and ourselves several days ago for increased sampling. I don't believe there were any releanes of that water yesterday,i 24 I

cafer:wsf Rsoorters, Inc..

It Releases were started this morning for a couple of hours.

I l

1a ir?,

i

i

'4 l

I RAW TRANSCRIPT - UNCORPbCTED

'6/79 mpb3 1

2 was released at a rate of about 100i gcllons a minute for a i

couple of hours.

Thiswasbasedo.dsempling,andtheStat'e 3

I d

and ourscivos are satisfied that the release was within those limitspermittedduringnormaloperlation.

S l

6 So with that quick overview, 'I wil'1 turn to ques-7 tions.

8 MR. FOUCHARD:

Maybe wo ought to have Vic just 6

run down the chronology that you go't this mornir$g and get the 9

l 10 '

.high spots, so that we all know from whence the questions f

come.

l-12 Vic, do you want to just hit the high spots on l

I3 that chronology?

i i

14 Ibelieveyouallhave[it.

If not, they do have 15 it back in the press room.

16 MR. STELLOc Okay.

I7 Yesterday we issued a, bulletin which will require I

18 other BtM plants to take certain actions related to the i

19 information wo learned in looking back at what happened here

M 2' '

20 at Three Mile Island.

a 21 I think if you look at ;the sequence of events that you have, you have a pretty del tailed listing by time of 22 23 What happened throughoat the accident.

I won't try to go i

through step by step, but rather hit what I think are the j

24 I

Wreal Reoorters. Inc.

25 important events that happened.

f i

13 If3 l

i i

I 5

l 5/79 1

RAW TRANSCRIPT - UNCORRECTED Ipb4 start with the ac{cident began by a trip 2

.Let's t

3 of the condensate feedwater pumps, which is a transient that I

4' is anticipated in the plant and which it is designed for..

S The w-f things normally would happen is the turbine would I

6 trip, the reactor would scram.

Thejauxiliary feedwater i

7 systems would have come on and the transient would have 8

essentially been terminated.

i 9

Yod keep that in mind as I try to go through 10 i some of the other events that have happened and.you'll see II that a number of other things happened which caused thin 12 t

transient to degrado, and this is how we've had the accident i

13 we've now had.

{

14 In about three to fifte n seconds following the 15 trip of the feedwater pumps, the primary circuit pressure began 4

1 16 to rise, which opens the relief valve on the pressurizer.

And i

17 the opening of the relief valve is again a pretty important t

18 event b'ecause as the pressure of the primary system dropped r

rid flws 19 it should have closed, but it did not.

4..

gn u

't 21 22 i

f 23 24 i

i

.4eeerst Ar:norrers, Inc.

L 25 rc -^ ('A J. i.

l i

5 1

1

l 6

i l

1 RAW TRANSCRIPT - UN ORRECTED ldavid 2'

About 30 seconds followidg the transient, the davidl I

3 auxiliary feedwater pumps I mentioned a moment ago started 4/G I

4 up, but they were unable to supply Water to the steam fis, mb 5

generators because their two independent flow paths were 6

blocked by valves that were closed.;

i 7

They were later sterted to deliver flow to the l

8 steam generators about eight minutes after the transient t

9 began.

The sudden increase that was observed in pressurizer i

l 10 levels about one minuto af ter the transient in significant j

11 because it provided information to he operator that again t

12 caused an action to be taken that was significant in 13 deternining the course of the accident.

14 About two minutes into the accident the emergency 15 core cooling systems came on.

All of the systems came on i

16 and worc supplying water to the core, but apparently 17 because of the change in pressurizer levels that was observed,,.

la the operator began to trip the pumps.

I; 19 The tripped the first pump at about four minutes 6

i 20 following the accident.

He tripped ;tluz second pump 11 i

21 minutes after the accident.

Ho left the third pump on, 22 supplying some water to the core.

The main circulating pumps 23 were continuing to provide circulation to the primary coolant 24 through the-steam generators until pproximately somewhat over ;

w Far: col Rezeters. Inc.

{

25 an hour -- from about one hour to about one hour and 40 minntes, l

131.0 l

I 7

RAW TRANSCRIPT - UNCORRECTED I

i I

david 2 at which time all the pumps in the primary circuit were 9

l 4/6 tripped because of observed conditions of those pumps.

3l I

i After about two hours into the transient is when 4

damage started to occur in the core.

The fuel rods at 5

that point apparently began to fail, releasing fission l

6 products to the primary circuit.

The fission products I-7 got'on the primary circuit, were going over it to the f

8 containment.

The apparent release of rad 6 activity to the i

9 environment was caused by a pump wh).ch was pumping the 10 fluid from the sump over into tanks in the auxiliary l

I 11 building.

j i

i 12 Those tanks in turn overflowed and caused i

I3 water to go into the auxiliary buililing which in turn caused 1

I4 the release.

15 The next several hours resulted in various i

h I0 attempts by the operators to first bf all release the

(

pressuro and put the plant on its.residuml heat removal II l

i 18 system.

Failing to accomplish this, a decision was made to l

increase the pressure in an atte'mpt to get a circulating i

20 pump back on and remove the heat through the steam generators, l

21 which is the normal heat flow path.:. That.was accomplished l

after about 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br />.

f 22 I

i 23 The plant'has been in essentially that condition i

24 since that time operating in the mode that's been described j

enJe:sA Reattess. fnc.

25 here in the past.

f I

srO s v.

.1.0

3. t.

I 8

t RAW TRN4 SCRIPT - UNCORRECTED david 3*

I We'ro ready for questions.

i 2

4/6 QUESTION:

br. "tello, did the operator have 1

3l any indicatcr.. on the control panels in rent of him that 4

the valves were closed that let watier in when the auxiliary i

5 feedwater pumps came on?

I

~

6 MR. STELLO:

It is my he did.

7 QUESTION:

He di

8

.s'1 STELLO:

Thc

':hoso, valves are indicated in 1

9 the control room as being opened od closed.

I 10 I QUESTION:

Is thero also an indicator that tells i

II when the sump pump comes on?

12 MR. STELLO:

Yes, there is.

I 13-QUESTION:

And when the ruptured _ disk blev on the 14 first tank, was there an indicatio also?

I.

MR. STELLO:

I con't know if there would be an 15 i.

i indicator.on it.

You could sea it as a rise in containment 16

[

I

~

pressure.

{

37 l

1B QUESTION:

Is there -- was there any other

{

F e.

19 indication that there might have been a leak out of the --

l l

20 out of this relief valve?

What evidence might he have had at i f

21 that early point that there was a leak, that the relief valve t

22 l had not closed and he was losing pressure that way?

i i

23 MR. STELLO:

I believe there might be some 24 thermocouples on the exhaust,'on the pipe that shows it's l

,1ea-Tw:arat Resortws, Inc.

25 still flowing fluid, buthewouldabsobeseeingitagainin i

1 l

13 d.C7 l

i i

9 I

I l

david 4 I

RAW TRANSCRIPT - UNCORRECTED I

2 1/6 precourc in the containment.

[

i 3{

QUESTION:

Was there anyl sort' of strategic reason 4

if ho knew that valve was open for leaving it open rather l

5 than trying to closa it as he finally did after a couple of 0

hours?

i l

7 MR. STELLO:

A question like that is very difficult l

8 to answer until you've had time to produce the various l

9 transients and look at an awful lot {of very detailed i

l-f 10 I nformation.

He has what you can consider to'be two l

II conflicting pieces of information.

12 He had is pressurizer level rising which would I

13 cause him to reoct that he was filling up the system l

Id too quickly.

At tho same time the pressure in the system j

I i

15 was dropping, which is indicative of the valve staying open.

I I

16 So it would be quite semo time, I think, before we complete our' I

17 analysis, until wo know pretty completely what happened, f

I 18 QUESTION:

If the transfer of the gases from the l

I9 auxiliary building to the containme t building isn't completed

{

t-20 by sometime tomorrow, at that pointiwill it be considered I

21 safe for those people who have voludtarily evacuated themse5ves i

22 from the area?

f i

2nd 1 23 l

l ab fis.

we a==ms,8ce-g ;f_('g 25

{

t.

10

'6/79

!adelon 1

RAW TRANSCRIPT - UNCORRECTED mpbl l

2 MR. DENTON:

There are two sources that I'd.lika I.

3 to see cleaned up in the plant. One, is the noble gases, which 4

the progress I've reported on today, and I want to watch the 5

operation t,o be sure it all goes smoothly and the gaser that I

6 aro in those tanks do get back.

And I'want to be care that l

7 those tanks represont a significant: fraction of the contribut-I 8

ors to the doses which are occurring from noble gases, t

9 The other isotope that I'm interested in I

10 '

. immediate containment on is iodine,; because iodine is coming 11 from the water in the auxiliary buildin g.

We've had plans l

I 12 and procedures under review to add chemicals to that water 13 which will in effect immobilize chemically the iodine in the i

14 water.

Those actions have not yet been takon.

15 So I guess I'd like to see the noble gas releases j n

andsheiodinereleasescomeAown.l 16 17 As I've said earlier,,I've advised the Governor..

l 18 cach night, and I prefer to postpone the decision until I've t

6 19

, gotten back to see how effective these measures are before f

s 20

, going on.

~

21

' QUESTION:

Mr. Denton, it is your advice to the I

22 Governor?

l 23 MR. DENTON:

I'm continuing to advise him.

24 QUESTION:

That's what I mean.

In other words, afeenet Reoorms,Inc.

you're continuing to advise him that this five milo situation 25 i

l 13 109

i

[

l 11 i

i I

1/6/79 RAW TRANSCRIPT - UNCORRECTED mpb2 l

2 should prevail?

j i

3 MR. DENTON:

I guess I'm trying to restrict my d

advice to technical advice, and whht the doses might be as 1

a result of either noble gaces or k.odines.

And I reali::e 5

i what his restriction is and what hh.s recommendations have -

6 l

7 bean in the past.

k 8

QUESTION:

You're not saying directly.

He is thel agent la charge of

-9 I

MR. DENTON:

10 evacuation in the State of Pennsylvania.

.l H

QUESTION:: :Are you saying Please do not bring A

l 12 these people back, or are you using a phrase like that, a i

13 direct statement, I do not think you should bring them back?

I Id MR. DENTON:

I give him a technical recommendation I

15 and let him balanco the social cost.

l 16 QUESTION:

The pump th t tripped at 1:15, would 17 you elaborate on that as to exactly what happened and how 18 serious that was?

19 MR. DENTON:

This is a ; contingency that we.have l

pf 20 been planning for.

It's the kind of thing that we thought 21 might happen until procedures are written for just this type 22 of event.

i i

23 The procedures call for starting up a second i

24 pump.

So what happens in the corelis the flow coasts down l

25 because power is lost in the first pump. There's a period of I

}

13~110 l

I

I i

12 l

i.

i I

/79 RAW TRANSCRIPT - UNCORRECTED mb3 i

2 about a minute or two during which natural circulation patterns 3l are being established.

The other pump was turned on, and 4

then it cm.e up to speed.

5 So the total duration of one pump running to havo l

6 the other pump running was two to three minutes.

What l

7 happens in the core during that time is that some of the i

elements are. running perhaps cooler! than others and may have 8

A 9

,gone up a little bit, and it appears that some of the hotter i

10 1 elements may have come down becausei of the changes of flow Il distribution in the core. ' In essencepi. :- the temperature in l

12 the core is essentially unchanged and we are just now pulling i

I3 out of the computer the change of temperature data.

j 14 QUESTION:

Since steps were taken to halt the I

i 15 leakage -- where did you trace the leakage at six o' clock that' i

Where did you' trace it to, and what steps did you havcl 16 nigh t?

}

I7 to take?

l l

18 MR. DENTON:

I don'.t know exactly.

And this is g

l e

19 a line, a half inch line which has been instal]cd in the past i

20 few days to permit venting of these! tanks back to the contain-l 2I ment.

22 This is not a normal typ3 of practice.

And so 23 extra equipment had to be -- valves, needle valves, and 2# (

control valves -- installed in this: line.

We also installed sJr.ed Reamters, lv.

25 a flame arrester in the line.

The line was checked'out with 13 1 1

13 I

/6/79 I

RAW TRANSCRIPT - UNCORRECTED mpb4 l

2 nitrogen under pressure in an attempt to make sure it was I

3 lenk-tigh t.

l i

4 Early in the morning when they first started l

5 venting, they did notice,".in the radiation monitors in those 1

6

. buildings, that there was a leak. I'm not sure exactly what l

7 steps were taken, but I would expect they were tightening the I

B flanges and tightening the valve stems.

l 9

QUECTION:

How long was the radiation released l

10 I into the atmosphere?

What was the extent of it, and what was )

l the impact on tha population?

12 MR. DtNTON:

Vory little change.

I went back and l

13 had someone. integrate the total aucunt of activity that had l

14 been released as of about twelve o' clock, and compared it to 15 previous days.

16 The total amount on a cumulated basis so far i

17 today 3 s about 60 percent of the arount which had been l

l 18 released over the same time period 'for t'a part four days.

[

19

-So it's down compared to the average of the last four days.

i l

20 It's ten to. twenty percent higher than the amottnt that had 1

I 21 been released yesterday as of the same time.

22 So in essence the total amount of activity that 23 has gotten out today is about the same as yesterday.

The 1

1 24 general trend is down.

And the amount of release, while it's {

.-r cw. n.=rr*. sae.

I 25 a puff, doesn' t change the overall total amount released.

1 :.

I i

i la 112 i

e 14 I

5/79 RAW TRANSCRIPT - UNCORRECTED l

mpb5 I'

2 The maximum dose rate in tha plume as detected j

hid f1ws 3;

by our helicopter is about.3 milligram'during the peak.

I 4

i 5

s; 7

8 9

10 11 12 13 14 15 S

17 l

18 l

g i

19 20

'e 21 1

I i

22 I

13 i

1 24 l

l 2r.:,<x na.wrters. inc.

25 13 U3 l

i

15 1

2 david 1

~

RAW TRANSCRIPT - UNCORRECTED i

david 1 2

QUESTION:

What is the status of your evaluation

'4/6 3

of the B & W plan?

Are you satisfied that the core is not I

fis mb 4

damaged to the extent it would prevent the natural circulation,

l 5

that that plant calls for?

MR. DENTON:

That evaluation is still ongoing.

6 i l

7 W6're having our Bothesda office run a lot of calculations l

I 8

in that regard.

I think we will issue a safety evaluation i

9 report and give our views formally on that in a few days.

I 10 still expect our outlook to be favorable, but we haven't j

l 11 completed the review of the selected temperatures and l

12 pressures that the applicant would propose to go to.

Yes, I have al! question for Mr. Stello.

13 QUESTION:

I 14 Going all the way back to the beginning of this incident, was l l

1 15 the loss of the condensate pump connected to the maintenance T

l 16 that was being performed on that system or was it an inadvertent 17 closing of the valve?

l i

18 MR. STELLO:

I don't know which category that i

Y I

19 belongs in.

I beliove there was some maintenance that normally i

I a

l 20 does go on; I could not identify the specific cause.

I 21 don't know.

I 22 QUESTION:

It can't be directly tied to the 23 maintenance that was going on?

24 MR. STELLO:

I said I dob' t know.

I don't want

,4r.ces nesorms. sm.,

25 to put it in either category.

N i.) 4

e 16 i

1 david 2 RAW TRANSCRIPT - UNCORRECTED l

2 i

4/6 QUESTION:

Mr. Stello, have you interviewed the i

3 operator on duty at the time of the -- of the --

4l Neither Vic lnor I have, but we have MR. DENTON:

l 5

people who are, investigators from our inspection and l

andtheyhaveinlterviewedtheoperators 6

enforcement office, l

7 on both of the shif ts, the midnight,to 8:00 -- the two l

8 shif ts over which this accident occurrad, and all the 9

operators have been interviewed.

t i

10 '

QUESTION:

Whatdidtheyltellyouabouttheir j

i Il reasons for taking the actions that they did?

i I2 MR. DENTON:

I don't know.

I haven't looked at it.l i

i 13 QUESTION:

This is sort of a two part question.

I f

Id wonder, maybe Mr. Stcllo and Mr. Denton could comment on it.

15 Reports about two things.'that the NRC hed several l

l 16 months before this accident:

they cited the erroneous 17 pressurizer as a problem in B&W reactors; and that five l

I8 years ago NRC critici2cd the fact that containment did not l

t 0

1 I9 isolate during emergency conditions.l 1

1 20 I wondered if you could c mment first on the fact i

21 that they were or were not cited, and why nothing was done to 22 l

follow up.

23 )

MR. DENTON:

Well, we -- you have to understand that we operate on a risk aversion b'nsis, and that no matter 24

,.rene n.oemn. im.,

25 l what happens in any plant, you can find a thick stack of j

i i

j e-

17 I

david 3 RAW TRANSCRIPT - UNCORRECTED i

4/6 2 f documents where we'vc been attempting to improve that area.

I i

3l I'm familiar with those documents, but I haven't gone back l

4 and studied them to see whether or not with hindsight we l

5 should have picked up something and done it differently.

But 6

that would be part of our overall investigation.

l 7

I think there were people in the Commission who 8

were concerned about some of these things earlier.

I 9

QUESTION:

Those two things particularly do you 10 '

recall.

II MR. DENTON:

Lot me ask Vic if he recalls.

l 12 MR. STELLO:

The first one, the level, I'm aware I3 of.

I I4 MR. DENTON:

Cortainly, with regard to the level 15 indicator, it was discussed -- it was a nubject of d!'i,cussion i

16 prior to the accident.

l 1

I7 QUESTION:

How long was,the coro partially l

l II uncovered, and if you knew that -- was it continued to be j

i uncovered or did it go up and down'h l

j 20 MR. STELLO:

That is a qtaestion aga. that you I

21 needtodoanawfullotofanalyscs.;beforeyoucandeterminoj principally there are two ques tionsl of concern:

22 how much the 23 core was uncovered and for how long.

The transients that wont on are going to require 1

.ca-ma n.=n.... iac.

I 25 considerable analysis beforo you're. going.to be abic to determine I

1.0 ?-

I

18 l

david 4 RAW TRANSCRIPT - UNCORRECTED

'4/6 completely the answer to that question.

We do know it was 2 ll l

l i

uncovered.

We do know the fuel did falf.

Piccion products 3L i

l 4l were released, and that some of the fuel in the core did l

. i get.to high temperatures.

l S

~

t QUESTION:

I thought someone had projected it at i

i three hours; is that a possibility?

7 l

MR. STELLO:

I don't think I'd want to venture a 8.

}

guess.

I'd prefer to have the analyses and not work on 9

i l

conjecture.

i I

QUESTION:

Did any safety problems or mechanical i

11 e

problems arise that prevented the robot from taking that l

12 I

sample?

13 i

l MR. STELLO:

None to my. knowledge.

g 14 i

t In order to look at how phey would set up, they i

had set up mock ups of the actions.that he would have to do 16 and practices going through those ' actions in this mock up I

situation before he would go in and 'ctually perform the 18 r

operation.

I Why the decision to not go that far and take the 20 i 11 l

sample yet is unknown to me.

QUESTION:

Does Mr. Denton know?

I MR. DENTON:

The only re son that I've heard was 23 that there are other activities goi g on in that same room 24 I

t

.cs Federas pe,otrees. ix.,

which worc considered of higher priority.

Until those changes:

25 l

13 4.P/

l

19 1

avid 5 1

RAW TRANSCRIPT - UNCORRECTED i

i

/6 2

were made, Herman would be a second priority.

I I

QUESTION:

Mr. Stello, is there any point in the i

3 I

i 4

chronology here when, as things are understood now, you l

5 could point your finger there and say once it got this j.

i 6

far it was sort of inevitable that it was going to be a 7

pretty had situation, things could,get worse?

I 8

In other words, is there a point beyond which it 9

goes down hill?

j end 2 10 ob fis.

11 I

12 i

1 13 I

i 14 l

V l.

1s 16 l

l l

\\

17 l

18 i

I t

19 l

20 I

21 I

22 23 i

i d

I

,\\cs.FewW flesor:tes. tec.

25 t

13~t*8 l

20

/6/7:s I

RAWTRANSCRIPT-UNCORhECTED Madelon I

2 mpbl MR. STELLO:

Well, I think at the point that the l

3; auxiliary feedwater pumps did not come on to perform their 4

function, we began going into what I consider to be still a 5

I transient, a very serious transient.

Had they been restored I

6 earlicr, this transient probably could have been terminated.

I 7

When the emergency corg cooling systems were l

8 activated, again, one could have considered, and from the l

9 information we now have there was a probability -- a certainty 10 I don't think we'll know until the analysis is ccmplete --

Il that that could have been a mechanism by which to successfully.

I terminato the accident, perhaps evEn without fuel failure.

12 1

13 I think at the point at which the two pumps were l

14 turned off is the point which set up a situation whern core 15 damage was likely to occur.

16 QUESTION:

When'is the! chemical treat =ent for l

i i

I7 iodine going to begin, and how long will that last?

1 I8 MR. DENTON:

I was hoping it would have begun j

days ago.

20 I just left the trailer with people who are 21 planning it, and I'm --

1 22 MR. FOUCHARD:

We're talking about in the plant, 23 right' I

24 QUESTION:

Yes.

6 I

,-e-Fecar,4 Rooorters, f,c, 25 MR. DENTON:

Apparently it's all tog' ether and

f 21 4

l 1

l I

/6/79 RAW TRANSCRIPT - UNCORRECTED mpb2 2

might begin today sometime.

3

~

QUESTION; How long will it'takc?

l 4

MR. DENTON:

I don't know for sure.

But the i

S issues originally were selection of the proper chemicals 1

6 to spray and identification of which compartments should l

7 really be sprayed.

And it just seemingly has taken a lot l

8 of time for everyone to settle down on how to do it.

9 But I'm optimistic that it's going to be accom-l 10 plished now and in the near futur$.

i I

II QUESTION:

Do you happen to have any figures 12 concerning the amounts of radiati n that woro emitted over-l 13 all?

I' 14 Also, what was the highest amount of radiation 15 that was emitted from the plant ati one particular time?

16 MR. DENTON:

I enn,give it to you in terms of I7 dose casier than I can quantitics.

18 We calculate each day the total population exposure as a result of the accident from noble gases.

And I think 20 our estimatos sort of came through mid-.3nt of yesterday.

21 So it was about 2100 manrem -- wh ch is a term I've used 22 before.

That's the accumulated total of added exposure to 23 everyone within a 20 mile radius or so up.

i Anc yesterday or the day before the incremental I

24 wrews A*=rtus. tac.

25 cxposure from releases was anotho 70 manrem.

So the total b

l 1

_m. o il a

n I

6/79 RAW TRANSCRIPT - UNCORRECTED mpb3 exposure to the public was a resulN of r&diation, the bulk 2

of that exposure occurred early on Anck the fast day we 3

calculated only added an additiona5 70.

4 I

5 We also rechecked our maximum individual I

6 exposure.

We still estimate that'no individual has received i

7

-- or that anyone continuously pres'ent at the north ridge 8

would have received less than 100 mr an hour, being continu-9 ously present there since the accident began.

l s

10 i QUESTION:

Mr. Denton, getting back to that, i

II pump that failed at 1:30 this afternoon, what would have i

12 happened in a hypothetical situatic'n that your second pump 13 failed?

Wouldn't that have been a very serious situation?

I 1

Id MR. DENTON:

Well, there are two other pumps 15 bcsides that that procedures call f.'r turning on.

The pumps 16 in the other room would havo been turned on.

17 So there are three sparc pumps behind the pung i

f I0 that failed.

MR. FCUCHARD:

One more', right here.

l 20 QUESTION:

Mr. Denton, on Wednesday you said that 21 Met Ed's failurc to malatain the auxiliary feedwater pumps in i

operation is a violation of their ik. cense.

22 23 Who within the company would have made the deci-24 sion' to continuc operating like that, and did the NRC knew l

e cmi n,xnm. im,

25 dod h?

13 ~ IN.

i 23 t

l

'6/79 I

RAW TRANSCRIPT - UNCORRECTED mpb4 2,

MR. DENTON:

That's a detailed item I would 3l really:.have to look back.into.

I can't-identify an answer tvid f1ws 4

to that, f

t 5

l l

6 i

l 7

l 8

9 I

io i i

j I.

n 12 13 u

15 16 17 18 l

19 i

20 i

'g 21

~

22

\\

1 23 24

{

,,u.a.x,..

25 1*d 1 2 2<

i

24 I

i 3 david 1

RAW TRASNCRIPT - UNCORRECTED I

i 3 avid 1 2 !

QUESTION:

This is for r.

Stello; isn't it i

i/6 3

the case that the bubble, the hydrogen bubblo in the reactor i

i fis. mb d'

developed on Wednesday and Met Ed didn't report it to you i

I 5

until Friday' l

6 MR. STELLO:

There probably was a bubble in 7

the reactor very soon af ter the transient was terminated, I

B at about 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> after the accident, and it most likely --

9 some form of it was there.

i i

10 '

The methods to try and understand if it indeed was I

Il there that dovoloped through the week. I don't believe you i

Allofourunderstandilng I

12 could call it not being reported to us.

I l

13 of the bubble finally evolved !.over sdveral days.

Thero is i

l f

14 no instrument to say there is a bubblo there.

You have to t

15 make inferences from measurements that were made in the i

16 plant.

17 QUESTION:

All right, as I understand it, the f'

18 hydrogen bubble came from the water-metal reaction.

Would t

19 1 that reaction have continued for hours or days after l

i i

l 20 Wednesday?

i 21 MR. STELLO:

No, once the temperatures get down l

22l below 1300 or 1400 degrees, the mobal-water reaction has Il 23 6 completely stopped, and there's almost no metal-water 24 reaction at temperatures at temperatures as high as 1800 wc:wt Remorrers, Inc.

25 degrees.

g ~ l'M i

I i

25 i

t i.

david 2 fORRECTED 1

A A

2 QUESTION:

As I understood the answer to her

,/6 j

3 question, you said the bubble continued t.o develop beyond i

I 4

Wednesday; the hydrogen wasn't -

i I'm sorry, bould you repeat it?

5 JUR. STELLO:

I 6

QUESTION:

As I understood the answer to her l

7 question, you said the bubbic continued to develop beyond l

l i'

8 Wednesday; the hydrogen wasn't in!there.

I wondered it --

I 9

MR. STELLO:

No, I didn.'t say the bubble 1

10 !

continued to develop beyond Wednesday.

I said it developed L

l 11 some time after the accident was terminated at 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> into l

l ~

l 12 it, and that the hydrogen evolution that occurred was i

essentially complete at that time.) There were some questions j 13 14 as to whether there could have been additional hydrogen l

15 involved as a result of radiolysis!of the water.

j-16 And I believe that the information we've had now i

i l

i 17 from people who have looked at it.has concluded that 18 radiclysis could not have occurred because of hydrogen So there was no more hydrogen evolution followin'g 19 overpressure.

i I

20 that point.

l l

l I

21 MR. FOUCHARD:

Harold wants to give you just a i

22 summary of the status, I guess, and then we do have to move along.

23 j

24 MR. DENTON:

I didn't give you the status I Aw ewd Resceters, tM.l s

i 25 normally do At 1:00 o' clock today the reactor pressure was l

13 v4

[

26 I

I i

I david 3 RAW TRANSCRIPT - UNCORRECTED i

2 4/6 1110 psi.

The bulk coolant temperatures were 286 degrees.

3l it'sperforminlg The recombiner on the containment is operatingi I

I very well.

d t

S It looks like the pere t of hydrogen in the f

6 containment is on the order of 1.8' percent; the containmerit building is still negative with -b.2 psi.

Its temperature 7

B is 83 degrees.

i.

9' QUESTION:

Havo you lost any instruments as a l

1 f

l 10 result of radiation?

MR. DENTON:

No furthe loss; the transmitter I

12 which failed earlier and I reported on appears to be I3 transmitting more reliably.

l i

It's giving now --

14 15 QUESTION:

You'rc saying the bubble didn't form 1

16 until 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> later?

Perhaps by is chronology at the 17 two hour point the core began to h at up and the bubble was 18 forming a

..at point.

Now, you're sure the bubble wasn't l

t i

I9 I f

formed before the 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br />?

I I

20 You said there was core; damage at the two hour i

21 point.

22 MR. STELLO:

Well, the core damage began some time 23 1 after that.

I don't know precisely when.

24 QUESTION:

You don't hav2 to have a bubble for i

Ace.Fer:erse H rmer?ers. Inc.

25 >

core damage?

13 i?b i

27 RAW TRANSCRIPT - UNCORRECTED i

I i

david 4 MR. STELLO: No.

There is another kind of a l

l 2

bubble, a steam bubble.

As the system depressurized and 3

the core became uncovered, meaning there' was a steam bubble l

in the system, and as gases evolved, therc was a mixt'ure l

5 of steam and hydrogen in the system which was going through l

i 6

a series of transients being vented out through the pressurize 7

relief valve; throughout that whole transient, hydrogen was l

8 evolving.

The bubble that we're talking about is generally 9

the bubble that we believe resulted in a bubble of hydrogen i

10 I over the reactor core.

1 II T said that in my judgment that bubble was 12 formed just about at the conclusic of the transient.

But 13 i

throughout the transient, clearly here was hydrogen in the Id l

system, and whether there was one 15ubble or several, at that t

i 15 point I believe is again conjecture.

There's no way we can i

16 make that inference.

I7 QUESTION:

But you did have core damage at 3

18 two hours.

MR. STELLO:

No, I said that I thought the core t

20 began to heat up.at some tirae following two hours, Ehere i

21 was core damage and --

22 l

MR. FOUCHARD:

Harold, you have one more thing 23 l

you want to say?

{

l 24 MR. Df:NTON :

Jual one more point I forgot to

[

.,..g.-,,,,,.i,.,

25' montion.

iie will be phasing back our round the clock coverage '

]

i 13 1'1

l i

i 28 i

RAW TrsANSCRIPT

- UNCORRECTED svid5 t

j that we 've had up until now.

We'l probably go to 3

principally two shif ts for our engineering staff; this.ill l

t i

4 be somewhere from 6:00 to 6:00 during the day, and another 5

shift will come on at noon time and work until midnight.

So l

6 there is some overlap during the time, the midnight to 6:00..

7 We will maintain survoillance of operations in the control i

I room, but we'll cut back our staff'which has been around l

8 I

9 the clock coverage.

k to MR. FOUCHARD:

Thank you very much.

I 11 (Whereupon, at 4:52 p.m.,

the press conference I

12 was adjourned.)

[

l 13 t

14 l

15 f

i.

16 l

i i

17 l

18 t

l 19 20 21 l

\\

t 22 23 24 l i

err. w M xews.tre.,

I 25 '

i 13 L"'d l

I i