ML19309G244
| ML19309G244 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 10/11/1979 |
| From: | Nitti D BABCOCK & WILCOX CO. |
| To: | |
| References | |
| TASK-TF, TASK-TMR NUDOCS 8005050463 | |
| Download: ML19309G244 (36) | |
Text
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8005050y[J r
i N U CLE A R R E G U L ATO R'.' CO MMIS SI O N
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IN THE MATTER OF:
THREE MILE ISLAND SPECIAL INQUIRY DEPOSITIONS DEPOSITION OF DONALD A.
NITTI Place - Middletown, Pennsylvania Date -
Thursday, 11 October 1979 Pages 1 - 36 3
re.chen.-
(202)347 3700 ACE. FEDERAL REPORTERS,INC.
OffiaalReponers 4M Nerth Capitol Street Washington, D.C. 20001 NATICNWIDE COVERAGE. DAILY
1 dgpl UNITED STATES OF AMERICA C
550 2
NUCLEAR REGULATORY COMMISSION 3
___________________x
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In the Matter of:
l l
5; THREE MILE ISLAND l
SPECIAL IMOUIRY DEPOSITIONS 6;
___________________x 7
.?
8 DEPOSITION OF DONALD A.
NITTI 9
10 Trailer 203 yy ;
l Thrce Mile Island Nuclear Facility 12 l Middletown, Pennsylvania 10:00 a.m.
3 11 October 1979 BEFORE:
GEORGE T. FRAMPTON, JR.
16 BILL JOHNSON 17 RON HAYNES j
un I
PRESENT:
i GEORGE L.
EDGAR, Esq., representing Mr. Nitti.
JOHN G. MULLIN, Esq., represehting Babcock & Wilcox:.
21 ALSO PRESENT:
CARLA D'ARISTA, NRC staff.
ELIZABETH OLMSTED, Babcock & Wilcox staff.
24 Am Federal Reporters, Inc.
25
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l dep2 1
EEE1EE11 2
Exhibits:
Identified 3
19 3
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20 3
5 21 3
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22 3
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10 l l
11 l l
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13 14 15 16 l l
17 18 i
19.
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22 23 l
24 Ace Fooer) Reporters, Inc.
25 1
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3 I
dop3 P,R_ O C E_ E_ D_I_ N G S_
2 CR7550 MR. FRAMPTON:
This is a deposition being conducted 3
of Mr. Donald A. Nitti of the Babcock and Wilcox Company by 4
the U.
S. Nuclear Regulatory Commission's Special Inquiry 3
Group on the Three Mile Island accident at Three Mile Island, 6
Pennsylvania, on October 11, 1979.
7 (Nitti deposition Exhibits 19-22 8
marked for identification.)
9 ' Whereupon, DONALD A. NITTI 11 i
was called as a witness, and having been first duly sworn, 12 l was examined and testified as follows:
13 EXAMINATION BY MR. HAYNES:
15 Q
Please state your full name for the record.
16 A
Donald Anthony Nitti.
I7 BY MR. FRAMPTON:
18 Q
Mr. Nitti, you furnished us with a resume of your 1
19 educational and professional qualifications, which I've had 20 marked as Exhibit 19 of this date.
21 Is that a photocopy of the resume you provided us?
2 A
That is correct.
23 (Counsel handing document to witness.)
Q On.a previous occasion you, I believe, had a, telephone
,,,,,,,,,,n,,,
25 conversation -- telephone interview with one or more people 1-
4 I
from our group.
Is that right?
,,94 2
A That is correct.
3 Q
And before we started today, I showed you a 4
memorandum that was written up by our group, recording some of 1
5 the answers to the quest. ions that they asked you in that 6,
telephone conversation.
7 I've had that marked as Exhibit 20, and I'd like to show 8
that to you, and ask you whether that is substantially an 9
accurate account of what you told them during that, telephone l
10 '
conversation.
II A
Yes, this is an accurate summary of discussions at I2 that time.
13 Q
Exhibit 20 reflects that on March 29, in the evening, Id you were asked by your management to estimate the maximun 15 amount of oxygen that might be in the gas bubble in the reactor 16 vessel at Three Mile Island.
I7 Do you remember who asked you to do that and what you recall 18 about the specific directions you got; what it was you were I9 asked to do and why?
20 l A
My' recollection is, as I was about to leave work on 21 Thursday night, Jim Taylor who is the manager of licensing, 22 caught me in the hall before I left; and said that.he'd like 23 me to stick around; because he thought there would be -- he 24 would need some help calculating the effects of hot radiolytic j
Am.Feder:A Reporters, Inc.
25 hydrogen generation in the reactor coolant system.
l l
1
5 dap5 1
He asked me if I could do it..
I said yes, and I stuck 2
around and started to do the calculations.
I remember that 3
was my first exposure to the incident -- the details of the 4
incident at Three Mile Island.
5 So, I was getting my stuff together to figure out what he 1
~
6 really wanted.
There was some confusion in that we didn't 7
know the bubble's size; we didn't know for sure there was a 8
bubble; and Jim was trying to convey to me the status of what 9
the situation was.
I l
10 '
He had some pressurizer level and pressure measurements to l
11 try and estimate the bubble size and so forth.
At any rate, i
l 12 whatever Jim was waiting for when he asked me to stick around, i
i3 cam through and the mission that finally came about when it got 14 to me was we think there's a gas bubble in the reactor vessel.
4 IS Based on this compressibility information, and take a look; i
16 estimate the composition of that bubble and -- when we were
{
l 17 trying to decide the ground rules as to what he meant by I
t 18 composition of the bubble, basically it came out that he was
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19 interested in the most conservative value or the highest oxygen l 4
20 composition thac could be in the bubble.
l 21 So, that's what I set about doing.
Those are the calculation ls l
22 that I generated on the night of the 29th.
I remember specifically 23 wrapping that up and going home sometime, you know, around 24 midnight; then getting home and getting called'several hours Ace Federal Reporters, Inc.
25 latsr by Mr.. Taylor; 3:00 in the morning or_something like_that i
a
6 1
to come back in and expand on the calculations.
d 5
2 So, you know, I'm pretty -- pretty sure of the date and the 3
informaiton.
4 Q
Let me stop you for a moment.
5 A
Okay.
6 i 0
You referred to scme calculations you made.
L..t me 7
show you what has been marked as Exhibit 21 as of this date, 8
which is four pages of calculations; and aske whether this is 9l
-- whether pages one, two, and four are copies of some of the f
i 10 l calculations that you did on the evening of the 29th.
I II (Counsel handing document to witness.)
12 A
Yes.
13 0
Okay, thank you.
do you know who did the calculations 14 that are on page three?
15 A
Charles Prior.
16 Q
And his initials are on that page, too?
17 A
Yes.
C. W.
P.
l l
18 Q
okay, thank you.
I take it from ycur own recollection l
19 of the sequence of events Thursday and Friday, you can establish 20 pretty clearly in your own mind that this was something you 21 did on Thursday night as opposed to Friday night, March 30th.
22 I3 that correct?
23 A
The date on the memo is written on the top.
I came 24 in on -- well, actua ly, when I came back the next morning, I km#6 o Reporters, Inc, 25 had all these papers because we were -- we didn't have tests l
7 l
i I
or anything, so I didn't want it to get lost.
27 2
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So I wrote on the top of it who the telephone call was to, 3
and the only name I could remember was Tom Novack, and the time i
4-and date on it.
SI So, I'm pretty sure of that time and date.
~
I 6
0 0.'.ay, but your notes reflect telephone conversation l
7 with Mr. Novack of the NRC at about 11:40 p.
m.,
on Thursday, l
8 March 29.
I 9 1 How did that conversation come about?
30 g
- well, Il Q
Who participated as far as you can remember?
12 A
I really can't remember everybody involved.
What it 13 was, is Jim Taylor, basically made verbal commitment to get back Id to Tom as soon as he had a response to Tom's earlier question.
15 So, I'm sure -- as soon as I finished the calculation, I 16 talked to Jim Taylor and Jim placed a call to Tom Novack; and it 37 was a conference call.
18 there was several people on NRC's end of the line.
Q Do you know why that was a conference call?
Were there j
20 peorle in different NRC buildings?
i 21 A
Two speaker phone calls.
There were several people on 22 the NRC end.
we had, probably, half a dozen people on our end. !
23 All I can remember specifically is, myself, Jim Taylor, and 24 that's about it.
There was, I'm sure, at'least one other AceJede,a Reporters, Inc.
25 person from licensing and_ probably three or four other people.
i 1
6 j
8 i
j Q
You don't remember the names of other people at the d
1 2
NRC, besides Mr. Novack?
3 A
No.
4 Q
But you do definitely remember he was one of the 5;
other people at the other end of that phone call.
i l.
6!
A Yes.
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7 Q
Okay.
What do you recall about the substance of 8
that phone call.
What you people said to the NRC people and 9l what their response was?
l 1
i 10 A
Well, basically, I went through my calculations and 11 told them what the hydrogen -- well, I told them was the 12 composition of the bubble was based on this radiolytic hydrogen --
13 radiolytic hydrogen rate, which has a corresponding radiolytic 14 oxygen production rate.
15 There was another page of calculations that didn't get 16 telecopied, but basically, it showed the gas contribution from 17 radiolysis; any air that may have been in the BWST water that 18 was injected; fission gas that may have been produced in the 19 fission process; and estimated the gas conten that is 20 prepressurized in the fuel rods; and an estimate of the 21 hydrogen dissolved in the reactor coolant.
22 It came up.
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23 Q
This would be hydrogen -- preexisting hydrogen --
24 A
It's the hydrogen predisolved in the reactor AW h erd Reporters, Inc.
l 25 coolant during normal operation of the plant.
When we took j
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9 I
1 I
that all into account, we had daout 11,258 standard cubic feet.
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At the reactor coolant temperature and pressure conditions, 3l that amounted to a bubble size of 284 cubic feet -- 284.5.
I 4
Q Let me stop you there for a moment.
Is that a 5
bubble of Sasically noncondensible gases?
I-6!
A Yes.
7 Q
In other words, that would assume no steam bubble.
i 8
Is that correct?
j 9 i A
That's -- that's correct.
I 10 Q
Esstentially?
l II A
That is correct.
So, what we looked -- if you look j
12 '
at that bubble, it would contain 5590 standard cubic feet of 13 hydrogen and 3.143 standard cubic feet of oxygen.
14 Now, the point that we made was that that is predicated 15 upon radiolytic oxygen and hydregen being produced at the 16 maximum theoretical g value.
17 G value being number of atoms of radiolytic hydrogen 18 produced per hundred electron volts of energy absorbed in the 19 coolant.
Okay.
20 So, when you'look at the composition of that bubble, it 21 showed like, maybe 5.5 percent oxygen, which would put it in 22 a combustible range.
23 So we were very clear when we talked to Mr. Novack to make 24 the point that this composition was in response to his direct Am Feem namnm. ine, t
25 question as to what is the maximum possible oxygen content;.not
I 10 1
really tying it to reality.
910 2
To make that point, we went through this dissolved hydrogen --
3 we knew that the bubble was much larger than this 200 cubic 4
foot size that we had calculated.
5 We knew there was other gas present.
We just assumed an 6l 800 cubic foot bubble.
To dilute the hydrogen partial pressure,! - -
i 7' we just assumed that and calculated what the dissolved hydrogen l 8
concentration would be.
9 We showed that that was much, much higher than what would 10 be required to produce -- to suppress the radiolytic hydrocen 11 production and the radiolytic oxygen production.
That seemed to 12 be a point that Mr. Novack hadn't considered when he asked the 13 question; and he asked us to telecopy calculations, you know, 14 showing that point; confirming that point.
15 Those four pages of calculations that you have there are 16 the calculations that show that the partial pressure of 17 hydrogen is sufficiently high to suppress the rediolytic 18 oxygen production and that that maximum number that we had 19 generated, really wasn't appropriate.
20 Q
All right.
And were these pages of calculations in 21 Exhibit 21 actually telecopied up to the NRC, to your knowledge?
22 Or do you have an impression if you don't know?
23 A
The commitment was made to telecopy those calculations l
24 to NRC.
Our standard -- and I just gave copies of the calculations Ace-Federal Reporters, Inc.
25 to Mr. Taylor, and it would've been Mr. Taylor's res'ponsibility l
11 I
to distribute those copies via telecopy.
do.
j The copy that you have there as Exhibit, what -- Exhibit 17 j 3
Q Exhibit 21.
l A
Exhibit 21, seems to be the copy that was transmitted to our customer at the -- at the site which either was given to NRC or -- and probably this is more appropriate -- there's 7
been another copy telecopied to NRC directly.
l l
8 0
You think there would be a different set of I
calculations?
10 A
The same four pages would have been transmitted to 11 l l NRC because I just got the impression that MR. Novack was in 12 Bethesda at the time he called.
13 0
I believe that's correct.
So it's your impression 14 that these calculations were telecopied to the NRC, but you're 15 personally not sure whether it was actaully done by Mr. Taylor.
16 A
Right.
17 Q
Okay.
Let me go back for a minute, now, to the 18 original conversation or-conversations that you had with Mr.
19 Taylor.
20 You said a moment ago, I think, that he wanted you to do 21 a conservative estimate.
What did you mean by that?
Did you 22 mean conservative with respect to the possibility that there 23 might be enough oxygen to reach flammability limits?
24 A
Right.
To make the most pessimistic estimate,
' Ac..r.ae,s n.oon.,. ine.
25 relative to th*e potential for hydrogen explosion.
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In other words, to maximize the amount of hydrogen and d.
12 2
oxygen present in the bubble.
I C
So the explosive nature of any hydrogen in the f
I bubble was not what the concern was as it was related to you.
5 g
7,,,
6l Q
It wasn't just, "We're interested in knowing whether !-
7 this bubble is steam or hydrogen; but we're interested in 8
knowing if there's hydrogen in there.
What possible danger, if 9l any, does it pose?"
Is that a fair characterization?
11 j
A Yes.
I think that is a fair characterization.
O Of what you understood?
13 A
I wasn't articulated quite like that, but there 14 cerrainly was a sense of urgency and concern over the potential 15 floor; enough oxygen present in the bubble to cause a risk of 16 an explosion.
I7 Q
Okay.
Let me just show you what I've had marked as 18 Exhibit 22, which is a memo to the record initialed by J.H.T.,
I 19 I
who I take it, is Mr. Taylor; and ask whether the first i
20 l
paragraph there is consistent with what he realted to you 21 about what he had been asked to do by NRC people.
l l
22 (Counsel handing document to witness.)
l 23 A
Yes, it's consistent.
One of the problems is in all 24 the verbal communication, some things get distorted, I. guess.
25 0
I can only ask you for your best recollection of
13 I
what Mr. Taylor conveyed to you.
j 2
A I didn't see this document until four or five months dcpl3 3
after the accident.
This says, raised a ccncern about radiolytic 4
decomposition of the gas and resulting accumulation in the l-5 reactor vessel, in that it might have been as much as 1200 6;
cubic feet.
i 7
That was certianly part of the concern.
It was more global i 8
in nature.
The concern was there was this gas bubble and l
9, could it -- you know, could it explode.
1 8
10 If it was radiolytic production, the hydrogen and oxygen l
l 11 would be in a stoichiometric ratio for the worst possible 12 explosive condition.
13 So, there really was a concern, not only about radiolytic 14 deccmposition but the composition in general; what other gases 15 might have been present.
16 0
Okay now, I'm going to have to ask you to help me 17 a little bit in explaining the difference between your I
18 maximum theoretical hydrogen and oxygen generation ratss and i
19 what you figured would be the more realistic calculations, and i
1 20 why there's a difference between those two things.
21 You started out by saying that on a theoretical basis, you calculated the total maximum amount of hydrogen and oxygen, thenj 22 i
23 you went back to assume there was an 800 foot bubble, and tried j 24 to look at how much hydrogen and oxygen might be in that bubble.
Aerens namnus ine.
l 25 On page four of your calculations that we've marked as l
i I
l 14 I
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Exhibit 21 near the bottom, there are four different volumes degl4 2
listed.
Based on the assumption of an 800 cubic foot bubble, 3
you've calculated that it would be primarily steam, but you've 4
also shown that there is substantial amount of hydrogen and I-5 oxygen.
0 Does that reflect your theoretical, rather than ycur realistic' l
7 set of calculations?
8 A
Yes.
9 MR. EDGAR:
Can we have that question read back to i
10 make sure that we don't have it inverted?
11 1 l
THE WITNESS:
Say that again, now, I'm sorry.
I BY MR. FRAMPTON:
13 Q
On page four, maybe you can explain to me what the 14 calculations there in cubic feet represent.
Do the assumptions 15 listed there -- it says assume an 800 cubic foot bubble.
16 do those estimated or calculated volumes of various kinds of gas also assume that maximum theoretical radiolysis production l 17 18 of hydrogen and oxygen have occurred or are occurring?
19 A
Yes.
Based on the calculation on page three -- on 20 page one you can see we came up with a certain number of 21 standard cubic feet of hydrogen and oxygen.
When those standard 22 cubic feet are compressed; and when you take into account the 23 other sources that I had previously mentioned about what was 24 previously dissolved in the reactor coolant, and all that; and 4e..pm non.n, ine, 25 i
l l
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15 i
I then you compress it to the condition indicate there; the 537 i
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$15 degrees Fahrenheit and 935 psig, you would come up with these l
2 3
compressed volumes which are consistent with the numbers on page one, which is based on the maximum theoretical production l
5 rate between the time of the accident and 2200 hours0.0255 days <br />0.611 hours <br />0.00364 weeks <br />8.371e-4 months <br /> on March 29, 6
So that would have been the maximum amount of radiolyta.c 7
hydrogen that could have been produced under the most optimum 8
conditions in that period of time.
9 j Q
Is there any way you can explain to me in lay terms I
I 10 how you arrived at the percentage relationship of these four 11 types of gaseous or semigaseous elements.
12 Can you do that on the basis of assuming that you had all I3 that hydrogen and oxygen generation.
This is given partial Id pressures and assuming that the bubble was that large.
This 15
.s what the ration has to be.
16 A
Well, I calculated the amount of each one of those II components and -- and I a.asumed it all went to a gas phase in 18 the reactor coolant system and didn't take into account any 19 i
losses released to the building or any thing else.
I
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20 I just assumed it was all there.
21 j
Q When you say "it", you mean the hydrogen and the 22 oxygen?
l 23 A
Hydroge:1 and oxygen, all the gas sources that I had 24 considered.
I didn't consider any loss from the systems.
So, Ace Ned Reponen, Inc.
this is sort of maxi. mum compositon,and -- or maximum content 11 i
I' 16 I
and the -- we knew the bubble was considerably bigger than the dupl6 200 cubic foot that I had calculated, or'could account for.
2 I
3 So, I calculated the specific volume of steam at that l
t l_
4l temperature and pressure, and assumed an 800 foot bubble, and l
Si came up with, basically, the dif ference as steam.
l 6l The steam would dilute the hydrogen and reduce the dbundance; -
1 7
or partial pressure in the coolant.
So that was a conservative I
8 assumption at the time; and it still is a conservative 9
assumption.
10 '
Now, of course, if the difference in volume was due to hydrogen 11 !
that would be even more conservative, because we'd have even 12 '
more partial pressure and it would serve to suppress the 13 reaction even further.
14 Q
Okay, now.
Let me get to that.
You said having 15 given the maximum theoretical generation rates, you also told 16 Mr. Novack and the other people from the NRC that you didn't i
17 think that these rates would actually be seen, because hydrogen I 18 overpressure would suppress this process of radiolysis.
19 A
Right.
20 Q
Where -- where would the partial -- where would 21 the hydrogen overpressure come from that would suppress this l
22 process; the theoretical process that you calculated here?
23 A
If we didn't have this going on, right?
24 0
What -- what would be -- can you describe why it is I
i Ace.Feceral Repe 4rs, Inc.
25 that there is a hydrogen' overpressure that suppresses this l
17 I
I Is that as a result of the dissolved hydrogen in the process.
(
-217 2
system from normal operations, or is that a result of the 3
ongoing process of radiolysis and recombination?
I 4
A That's a good question.
I don't know how I'm going Sl to answer that question.
Rephrase it; could you give me that l
6lj i~
question again, because the answer is awkward to phrase.
t 7
I just want to make sure I understand it correctly.
8 Let me try.
9 Q
Okay.
i' 10 A
If the radiolytic process did not occur, then there i
II !
would not be sufficient hydrogen overpressure to suppress the I
12 '
reaction, right?
13 Okay, if that were the case, and I looked at all the gas Id sources, there would be no way to account for any bubble of l
i 15 any significant size because of the composition that I had I
16 come up with; which was over 11,000 standard cubic feet, now.
I I
17 I There's a compression ration of about 40 by the time you l
18 get into the reactor system; 9000 of that 11,000 standard I9 cubic feet was a result -- about 9000 was a result of the 20 radiolysis porcess.
21 So, if you subtract that 9000, you have very little gas, 22 to account for in the bubble.
l The one item we left out was the metal-water reaction, which 23 l
only contributes hydrogen.
So any mysterious increase, or l
24 Ace FederCD Reporters, Inc.
6 f
25 bubble size larger than this 200 standard cubic feet either had to be steam or hydrogen.
j
18
.l 1
Q Okay.
Let me get to that in just a second.
Was i
pl8 2
what you were saying to Mr. Novack, you don't see -- you're not I I
3 likely to see any net or free hydrogen or oxygen such as you have l
4 liste.1 here, because this process does not generate free Si hydrogen and free oxygen under these circumstances.
l~
6; Is that a fair summary of it?
i t
- 7' A
That -- yes, that's a fair summary.
8 Q
Okay.
My next question is whether there was any 1
1 9i discussion of that conversation, that you remember about the l
l t
10 l possibility of zircomium-water reaction causing hydrogen 11 generation in the system.
12 !
In other words, did you or anyone say to NRC people or 13 was it discussed, "Look, if you've got a lot of hydrogen in l
14 this bubble, it's got to come from zirc-water reaction; it's 15 not coming from radiolysis."
16 A
I can't rec:all getting into that specifically with 17 Mr Novack on the evening of the 29th.
It certainly was i
18 tipparent that that of the sources of hydrogen, that I could i
19 account for.
l 20 The five sources that I previously mentioned; the one tnat 21 is conspicuously missing, is metal-water reaction.
The reasoa 22 that is missing, is that adds hydrogen to the bubble which; 23 one, affects it's size, but doesn't affect the explosive t
24 potential.
l Am4 0 Remners, lrw.
l 25 This calculation gives you the most pessimistic l
t s
19 l
l I
interpretation from an explosive composition, which was my d.
.9 2
initial mission.
3
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Q Was it communicated to you before you did these that this was a hydrogen bubble, or substantially l - l 4
calculations, a hydrogen bubble.
5 1-f-
6 Was it assumed that there was a lot of hydrogen in it, or j
! ~~
7' was there raised a question as to what it was?
Whether it 8
could still be all steam, if there really was a bubble there.
9 A
Well, the question came about in the broad context; I
I 10 do the best you can to estimate the composition of the bubble.
l II l Q
Whatever it is?
I I2 A
Whatever it is.
I3 Q
How could we have I. bubble; in other words, if we Id save a bubble, what's in it?
15 A
What's in it.
The presupposition was there was a 16 bubble of some size based on this compressability information. l I7 Now, do the best you can to estimate the composition from i
i 18 the standpoint of what's the most pessimistic composition that I
might be there that could cause a hydrogen explosion -- :an I9 I
20 cause un explosion due to the radiolytic composition of any i
21 coolant that might be there -- coolant that might decompose.
22 That is what that first four pages of calculations was 23 intended to impress.
The presence of steam bubble never really i
24 came up on the 29th.
The reason is if you look at the reactor laceA.sn.conm.inc.
20 coolant temperature and pressure, it was subcooled und it was -
l I
20 1
ne w uld expect the partial -- the vapor pressure of water to doo20 2
be relatively low under those conditions, and not much steam 3
to be present.
4 However, we also didn't fully understand the temperatures 5
that the core had reached, and the length of time that the i
6 internals of the reactor coolant may have been heated to I
7 temperatures above the norma.
7 ting temperatures and that 8
sort of thing.
9 So, it was a -- and I can't remember the day at all -- it 10 was a day or two later when somebody brought up the point of 11 whether this bubble could have been a steam bubble as opposed l
12 to just a hydrogen bubble -- hydrogen bubble.
13 I discussed it with Billy bingham, who has a very strong 14 technical background in heat transfer, and he did some "back 15 of the envelope" calculations and kind of convinced himself 16 and me that it wasn't a steam bubble.
17 Now, if I had to put a time frame on that, I would say it 18 was some time on either March 31 or April 1, because at that 19 time we were doing bubble size calculations, and the bubble l
20 was shrinkir.g very quickrf.
l I
i 21 01r into.:pretation was we wure either degassing the coolant l
22 much more eft ciently thar we thought we could do it, or we 23 thought we ha.d e leak in t he gas phase, where the bubb.'.e was.
24 But we didn't interpret it as the collaps3 ng of a s team
- m Federal Reporters, Inc.
25 bubble.
i I
t 21 I
Q By that time, you were assuming that it was l
I 1
2 dep21 substantially hydrogen.
}
3 A
Right.
And the main reason is that the hydrogen I
- l nwdwxs all corrolated.
The leak rate was -- showed a linear 1
5l decrease in bubble size which would be compatible with the 6
theory of there's a small leak.
The system is under constant i
7 pressure.
8 The escape rate ought to be constant over that period of 9
time.
The hydrogen concentration in the building was going up 10 t and when the bubble size stopped, the hydrogen concentration in
~
11 l the building stopped -- stopped increasing.
12 !
j So, the whole scenario fit together.
We didn't really 13 pursue looking at the possibility of whether it was a steam 14 bubble in any great depth.
15 Q
Okay.
Let's go back to your comversation that 16 evening; the conference call.
The conversation with the NRC 17 people.
18 A
On the 29th?
19 0
On the 29th, you mentioned that in your own notes 20 you used,that you also considered the possible contribution of 21 gases from inside the fuel rods.
Am I correct?
A (Nods in the affirmative.)
3 Q
Those would only get out in the system if there were 24 Ace Fedece Recw no 3, Inc.
s l'
25 A
Right.
i
22 I
d2p22 Q
I notice that doesn't appear to be included in the 2
four categories that are listed on page four of your calculations.
3 Is there a reason for that?
A Well basically, it was so small it's -- well, let's see.
The gas that's prepressurized in that -- it was mostly 6
~
helium and it was 1000 out of the 11,000 cubic feet.
7 So, it's 1000 as compared to 9000 from the hydrogen / oxygen 8
and it was -- we had all this -- it would only act as a 9
dilutant and we had all this steam acting in there as a i
i dilutant, so it really didn't affect the conclusions very much.
11 I didn't -- I didn't know that number there precisely at the 12 time, either.
13 0
Were you making any particular assumptions about 14 whether there had bcen fuel failure or had not been fuel 15 failure?
16 A
At that time, I assumed -- see, this calculation 17 continued on to the next day.
Some of the people that I 18 needed relative to the fuel characteristics and that kind of 19 stuff weren't available until the next day.
20 So, some of these numbers got refined the next day.
So I 21 l
may have gotten more detailed information, on say, the i
l 22 l
prepressurization of the pins and that sort of thing that I i
23 l
l l
didn't know on Friday night -- on Thursday night.
i 24 Cates dat you reCan that Ace-FocerJ Reporters, !nc.
25 Mr. Novack's response in the telephone call was that's a new l
liii,:L
23 I
wrinkle, or words to that effect.
d:
13 2
A Yes.
3 Q
What was it he thought was a new wrinkle?
4 A
The fact that the radiolytic hydrogen reaction would
_l 5
be suppressed by the hydrogen overpressure.
6 -
Q Why would that be a new wrinkle?
Because you would l
7 be telling them that if you've got a hydrogen bubble it's not 8
coming from radiolysis; it's coming from somewhere else?
9 A
No.
Unless somebody's had previous experience 10 dealing with radiolytic composition, all they do is read reg 11 guides or something like that, and it goves the radiolytic 12 l decomposition rate and they don't understand the various 13 perameters that affect it.
Id We had done some -- I had been involved in some experimental 15 work on radiolytic hydrogen production and we know that you can 16 get any rate you want, just depending on the kinds of I7 conditions which you conduct the radiation -- any rate between 18 zero and a g value of
.5.
19 0
I guess what I'm trying to get at by my question, 20 is whether if you told him you're not getting any hydrogen 21 or oxygen; net hydrogen or oxygen from radiolysis.
.22 If that inevitably leads to v.he conclusion, "Well, we'd 23 better look at whether we've got a lot of hydrogen from 24 i sm.F6
.I Reporwrs, Inc, 25 Is that almost an inevitable conclusion that one would l
l
24 6924 reach, even if you didn't discuss it in the phone conversation? !
2 That's what I'm trying to get at.
3 A
Well, I think that's a conclusion that one would reach.
4 I think that we had reached that conclusion that night.
5 Q
Yourselves?
6 Although, we hadn't really pursued the A
Yes.
t 7
calculation in any -- in any depth.
That was the first, well 8
I guess that 's why Jim called me back at 3:00 in the morning 9
and said to come on in and let's pursue this calculation, 10 because it's very important.
11 Q
When you say this calculation, you mean this zirc-12 water question?
I3 A
Right.
Finish the whole calculation on the bubble, I#
because they were concerned about -- well, the zirc-water, 15 the bubble size and the -- they were concerned about the growth 16 in the bubble.
17 See, they wanted to say, "Okay, if there is no radiolytic 18 hydrogen production, then the bubble should not be growing."
19 They wanted to get real precise measurements on bubble size.
~
20 So if there wasn't radiolytic hydrogen generation, they could, 21 sort of, monitor the increase in bubble size or something like that.
23 That was the thought process they were going through, but 24 we got some phone calls that showed the next day; I don't Ac..e.o.,a n. con.,.inc.
25 remember what time that day; where we discussed as much as i
25 I
dep25 15 percent metal-water reaction with members of NRC.
2 Q
All right, when you say 15 percent; you mean 15 3
percent of the cladding gone to that reaction.
A Right.
5 Q
Used up in such a reaction?
A Right.
7 Q
Of the zirconuim in the cladding?
^
8 A
15 percent of the zirconium in the cladding reacted --
9 would have had to react with reactor in the coolant to produce 10 the bubble size that we were measuring.
11 Q
Okay, but you don't recall that specific subject 12 being actually discussed in the conversation on the evening 13 before?
14 A
No.
15 Q
You think it wasn't, or you just don't have a 16 recollection one way or the other?
17 A
I recall that we thought it was too premature.
I 18 don't think we really had pursued that calculation, because 19 we didn' t know the bubble size.
i 20 l
So, we -- you know, we expected the difference in size from 21 l
what we could account for; would have to be due, probably, to 1
l 22 metal-water reaction.
23 But we didn't dwell on that point.
As a matter of fact, f
24 we probably avoided that point on the night of the 29th.
l ac..A,e n.oort.,,,inc, 25 0
-Do you remember when you first learned, if you did,
26 dsp26 that there probably had been a hydrogen detonation in the 2
reactor building on Wednesday?
3 (pause.)
4 A
I can't -- I remember seeing the curve, but I Sli really can't remember what date I saw it on.
6!
Q Approximately.
7 A
Somebody, we were putting all these preameters that
~
8l would be plotted and sticking them up on the wall.
As soon as 9
I s aw it, you know, it looked like it was obviously a hydrogen 10 explosion on the -- and that was 9 hour1.041667e-4 days <br />0.0025 hours <br />1.488095e-5 weeks <br />3.4245e-6 months <br />se after the accident; 11 which was, I guess, on -- that happened on Wednesday, and I 12 probably didn't see that curve until Friday at the earliest; 13 Saturday at the latest.
14 So, even thought it happened on the 28th, I didn't see it 15 until the 30th or the 31st.
16 Q
Okay.
Now, let me ask you about Friday the 30th.
17 You said you do recall some conversations with NRC people about 18 the zirc-water reaction.
19 Do you recall that you participated in such conversations,
~
20 yourself?
Or is this in impression that you have from seeing 21 transcripts or tapes or talking with people afterwards?
22 A
At that particular time, I was probably on the 23 phone 10 times a day with different people from different 24 cerw.,e n.oon.n, inc.
organizations; NRC, several times a day with NRC; and just 25 basically giving the a blow by blow of everything we were doing.
I
27 I
So, I really don't recall participating in one specific to27
~
2 telephone call, other than what we have in the record, that 3
says we did specifically talk to somebody on this subject.
3ut I can't remember that --
5 MR. EDGAR:
Off the record.
6 (Discussion off the record.)
7 MR. FRAMPTON:
Let's go back on the record.
8 BY MR. FRAMPTON:
9 Q
Mr. Nitti, your notes of your telephone conversation 10 made by us indicate that you do recall on Friday or Saturday, 11 talking with Mr. Salvatori of Westinghouse about the oxygen 12 generation issue.
I3 Do you recall any discussions on Friday or Saturday with
^
NRC people about that subject again?
15 In other words, did people come back to you questioning 16 your view on that or asking the same question over again, that 17 you can remember.
18 Or did it continue to be an issue; if, you know -- if you
~
19 recall?
O A
Well, I'm pretty sure -- positive that the call from Romano Salvatori was on Saturday, because I was impressed that 22 Westinghouse'was working on Saturday and willing to call us and 23 offer assistance.
24 So, I'm positive that was Saturday; and I'm also positive Ace P ets Reporters, Iric.
l that the response that he was able to provide was very prompt.
i
^
o
i 28 I
dep28 I'm sure it was later on in the day of Saturday that Dr. Connor,,
2 you know, Mr. Romano had contacted Dr. Connor and gotten a 3
response from him and had gotten back to us; then I called 4
Dr. Connor and discussed it some more.
5 Basically, he confirmed our previous conclusion that the 6 hydrogen overpressure would have suppressed any radiolytic 7
oxygen formation.
8 Q
Okay, my question is, really, whether you recall 9
this being an issue that anybody from the NRC directly came back, 10 to you on, or to anyone else at B & W.
I 11 i A
I --
12 Q
Raising the problem new or questioning --
i 13 A
My recollection is very clear on that, and that is 14 I don't recall any conversation with any memeber of the NRC 15 that rehashed the concern relative to whether radiolytic reaction i
16 l
was supressed.
I I7 WehadmanycallswiththeNRCoverthatperiodoftime,butl 18 it was always on something now; not going back over something 19 that we had previously communicated.
i 20 0
Do you recall whether you knew this was -- continued 21 to be a cancern on semebody's part?
22 A
Well, yes.
l 23 l
0 In the media or among people working at the site or 24 whereever.
Ac...
.i nan.rs, ine, 25 A
Well, I really didn't have a whole lot of time to
29 I
daa29 read the newspapers at that time, but the -- and there were a 2
lot of people involved at NRC, and in our shop.
3 There was a lot of planning and questions going on relative 4
to growth in the bubble, or potential for hydrogen explosion; 5
the ability of the veseel to withstand explosion and all these 6
things had been turned on and were progressing for -- into, I'm 7
sure, throught April 1st, anyway.
O So, to some extent, I was curious as to whether tha 9
Commission believed what we had told them about suppressing the 10 radiolysis reaction, or whether they were proceeding on another 11 course, which was assuming that it was continuing.
12 Since I only had a limited perspective on the overall 13 operation, I just didn't know what the controlling criteria was I#
for that.
15 Q
Well, if you were aware that other people were 16 working on the question of what happens if there's a hydrogen I7 explosion, it would seem that this continued to be a concern 18 and; yet, based on your calculations, one ought not to have 19 been concerned about'it.
A That's correct.
Q Did that ever come to your mind as a contradiction of 22 any kind?
23 A
Very clearly, very clearly.
24 (Laughter.)
25 Q
Vid you every have conversations with other people
'h e
w w
30 I
dgp30 Friday or Saturday doout the -- in essence -- to why the hell 2
anybody is worried about this; or isn't this all very theoretical?
3 A
I've made those statements, but obviously not to 4
people in the right positions.
You know, we don't all 5
communicate directly with the White House, you know, this is --
6 (Laughter. )
~
7 Q
Let me ask you about that.
I certainly don't mean 8
to suggest that you should have, you know, that you bore any 9
responsibility for, you know, setting the country straight.
10 Do you know whether other people were working on this II problem for the NRC or Met Ed from 3 & W down at Lynchburg made 12 any efforts to remonstrate with anybody about whether this 13 really was a valid concern; that there was an explosion Id potential?
IS A
I got the impression on -- probably clearly on 16 Saturday from talking with Dr. Connor; and several telephone 37 calls took place on Saturday that he had talked directly with 18 NRC before he had talked with me.
That he had told NRC the l9 same thing.
20 l
Somehow or other -- and I can't remember who told me to 2I get in touch with Bob Ritzman at SAI, but I talked to him and 22 l
got the impression that he had been talking to the Commission i
23 and I sort of got the impression that everybody in the country 24 that had any knowledge of radiolysis was working on it.
sa-vuaa nnnnen.tx.
25 So, I just figured it was in good hands.
There was a lot i
31 dep31 1
of contingency planning going on.
But I just didn't ha<e the 2
overall perspective as to what were the driving forces and what 3
were the real concerns; who was worried about what.
4 MR. FRAMPTON:
Off the record for a minute.
5, (Discussion off the record.)
i 6
MR. FRAMPTON:
Back on the record.
Do you want to 7
th question, Bill?
8 BY MR. JOHNSON:
9 Q
Don, I'd like to know something about what you call 10 the substance of your conversation with Bob Ritzman.
Was it 11 a technical discussion; were dou discussing differences of 12 conclusions?
What do you recall?
13 A
Basically, all I can recall is that somebody said 14 that Bob Ritzman was working on this problem.
I called Bob.
15 We discussed it and he was -- we discussed it in some detail.
16 I know, I have a whole page of notes of various things we 17 discussed.
And -- the bottom line is that, basically, he was 18 in agreement with wha.t we had said relative to the hydrogen 19 supressing the radiolytic production of hydrogen and oxygen.
20 That was my main concern in talking to him.
So it didn't --
21 it helped -- you know, us from looking into it anymore.
It was 22 another confirmation; and we were tyring to make sure that the 23 rest -- nobody else had any concerns relative to the technical 24 asssumptions that we had made; realizing the importance of the Ace-Fooer2 Reporters, inc.
l 25 conclusion.
32 I
So, we were just looking for support and basically, he 2
dop32 supported our conclusion.
We felt good about it, and didn't 3
really follow up with Bob more than that one telephone call.
4 0
Was: this on Saturday if you recall?
~
5 A
I'm pretty sure it was on Saturday, because I know it i
I 6' was on a weekend; and I know I called him at home.
Whoever gave 7
his name gave both his business number and his home number.
O So, I'm pretty sure it was on Saturday.
9 Q
Could I ask in connection, were there any other 10 estimates made on the effect of impurities on recombination 11 rates.
In other words, you mentioned only hydrogen as being --
12 promoting recombination; but how about -- at any point in this 13 period, was the effect of fission products due to the damaged 14 core and so forth have any possible influence on suppressing 15 recombination, even in the presence of hydrogen or that being 16 a factor.
17 Was that considered at all, to your knowledge?
18 A
We didn't consider it.
Now, I don't know if Bob's 19 study got into that or not.
I know the follow on study that 20 Westinghouse -- that Argonne is doing now, is looking at that 21 sort of thing, but that's -- we were working in real time, with 22 a few hours to reach conclusion.
23 We were not looking at it in that great a detail.
We weren't 24 even e Uipped to do that if we wanted to.
Ace-Federal Reporters, Inc.
25 BY MR. FRAMPTON:
l I
33 I
dep33 Q
Mr. Nitti, other than matter that we have already 2
discussed, here, were there other issues or problems that you 3
worked on in response to the accident over the period from March 29th to April 1st, or 2nd?
5 If so, could you summarize, very briefly, what they were 6
insofar as you remember?
I 7
A Well, we talked primarily about the compositon of 8
the hydrogen bubble.
My overall responsibility was to 9
coordinate all the radiochemistry and chemistry aspects of the l
10 accident.
11 So, I was involved with estimating the bubble size, and 12 tracking the bubble's size; as a function of time, refining the 13 calculational techniques on the bubble; establishing the statistical error bars that we might expect on the size of the 15 bubble.
16 Following the amount of activity that was observed in the I7 reactor coolant when we first got the samples back, then there 18 were a whole lot of other radiological considerations relating 19 to radiation damage to various components that we were working
^
20 on.
21 But that basically summarizes my involvement other than the hydrogen bubble composition.
23 Q
Okay.
Thank you.
Let's go off the record for a 24 Awfuners Reporters, Inc.
25 (Discussion off the. record.)
I
34 I
dep34 MR. FRAMPTON:
Back on the record.
2 BY MR. FRAMPTON:
3 Q
Mr. Nitti, you referred to two other documents during 4
the deposition.
You referred to some extra calculations, back-5 up calculations that you did on Thursday; and you referred to some 6
notes of telephone conversations you had with Dr. Ritzman and l
7 Dr. Connor.
O For the record, during the break, we asked you to provide 9
us with photocopies of those back-up calculations, which are 10 pages 5 through 10 which would follow on pages 1 through 4 of Exhibit 21.
2 We've also asked you to provide us with notes that you had with telephone conversations with Dr. Ritzman and Dr. Connor I#
with the understanding that if that is only part of a page full 15 of other notes, that you can give us the extract thrt refers 1
16 only to those conversations.
17 Is there any problem about getting us copies of that 8
material?
19 A
No.
MR. EDGAR: One correction for the record.
The 21 statement was made that the additional calculations on pages --
THE WITNESS:
Five.
23 MR. EDGAR:
Five through ten were done on Thursday.
24 nce F.
si Reporters, Inc, 25 they done so we can get a correct identification-l l
35 All the calculations on pages 5 through !
I THE WITNESS:
dsp35 10 were either done on Thrusday or Friday.
2 3
BY MR. FRAMPTON:
Do you recall that some were definitely done 4
Q 5
Thursday?
i-since it's in such
!~-
6l a
rim pretty sure that page 5, i
l l
7 detail was done on Friday.
Page 6 may have been done on Thursday, because it's -- it covers the same kind of material, 8
so when I reshuffled 9l but it's a little bit more approximate, I put the most the pages and put the calculation in one place; 10 II accurate stuff first and --
I2 MR. EDGAR:
What about page 7?
s I3 THE WITNESS:
Page 7, I think, was partially done It was started on Thursday and was revised some-14 on Thursday.
Page 8 was probably -- it was probably Friday, 15 time on Friday.
16 and page 9 was probably Friday.
Page 10 was Friday.
I7 MR. EDGAR:
Okay, now when you refer to Friday, can 18 you give him --
the first half of page 10 I9 THE WITNESS:
Excuse me, It ended with the calculation on 20 we started on Thursday.
21 Friday.
Could you explain, when we're talking 22 MR. EDGAR:
23 about Thursday and Friday, here, could you go back just to pin down what your work day consisted of on Thursday and Friday?
24 Well, my work day started at 8:00 in i
Am Leral Reporters, Inc.
25 THE WITNESS:
i
36 I
l the morning and normally ends at 5:00 on Thursday.
But most of 2
that was not related to the hydrogen problem.
My involvement 3
with the hydrogen problem started around 5:00 on Thursday night and ended probably 12:30 on Friday morning'.
BY MR. FRAMPTON:
6' i
Q 12:30 a.m.?
7 A
12:30 a.m. Friday morning and then it started, like, 8
3:30 a.m. Friday morning and ended -- I don't know -- sometime 9
around midnight Friday night.
MR. EDGAR:
Okay.
11 MR. FRAMPTON:
Mr. Nitti, thank you very much for 12 your cooperation and your time.
We appreciate it.
THE WITNESS:
All right.
(Whe ';;cpon, at 11:15 a.m., the deposition was adjourned. )
15 16 17 18 19 20 21 22 1
23 24 Ace Feder3 Reporters, Inc.
25 1
^
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