ML19318A766
| ML19318A766 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 06/19/1979 |
| From: | Bennett N METROPOLITAN EDISON CO. |
| To: | |
| Shared Package | |
| ML19318A760 | List: |
| References | |
| TASK-TF, TASK-TMR NUDOCS 8006240123 | |
| Download: ML19318A766 (25) | |
Text
.
s UNITED STATES OF AMERICA I
l NUCLEAR REGULATORY COMMISSION
^
i l
il' In the Matter of:
l 2
IE TMI INVESTIGATION INTERVIEW 3,
of Nelson K. Bennett, fiaintenance Foreman, Nuclear 4
1 5
6 7
8 Trailer #203 9
NRC Investigation Site TMI Nuclear Power Plant 10 Middletown, Pennsylvania 11 June 19, 1979 12; (Date of Interview) 13 July 6, 1979 70B iranscript Typed) 14[
- 311 15 (Tape Number (s))
16 17' 18!
19 20 21!
NRC PERSONNEL:
22 Mr. James S. Creswell fir. Mark E. E ner i
24 25 8 u o 624 0\\}3 I
C--- - ---- -
1 RESNER:
NELSON K. BENNETT, Mr. Bennett is employed with the Metropolitan 2
Edison Company and his job title is Maintenance Foreman, Nuclear.
3 Present time is 9:05 a.m.
Today's date is June 19, 1979.
This interview 4
is being conducted in Trailer 203 which is located just outside of the 5
S uth Security Gate to the Three Mile Island facility.
Individuals 6
present representing the NRC at this interview are MR. James S. Creswell, CRESWELL.
Mr. Creswell is a reactor inspector with Region III of the 7
8 U. S. Nuclear Regulatory Commission.
Speaking and moderating this interview is myself. That's Mark E. Resner, RESNER.
I am an investigator g
with the Office of Inspector and Auditor, Headquarters, the U. S.
10 Nuclear Regulatory Commissioi Prior to taping this interview, Mr.
Bennett was given a two page dociment which explained the purpose the scope and the authority by which the Nuclear Regulatory Commission conducts this interview.
In addition it apprised him that he's ntitled to a representative of his choice to be present during the 5
interview should he desire one and that in no way is he forced to talk to us should he not want to.
On the second page of this document Mr.
Bennett has answered three questions which I will state for the record.
Question 1 do you understand the above.
Mr. Bennett has checked yes.
Is that correct Mr. Bennett?
20 21 BENNETT:
Yes.
22 23 RESNER:
Question 2 do we have your permission to tape this interview.
24 Mr. Bennett has also checked yes, is that correct Mr. Bennett?
25 Y
2 1
L*NNETT:
Yes, it is.
2 3
RESNER:
Question three do you want a copy of the tape.
Mr. Bennett 4
has checked yes indicating he would like a copy.
Is that correct, Mr.
5 Bennett?
6 7
BENNETT:
That's correct.
8 RESNER:
Ok, we'll provide you with a copy of the tape at thc conclusion g
f the interview.
Mr. Bennett has signed and dated this document and 10 indicated that he fully understand its contents.
At this time I would 17 ask Mr. Bennet if he would please provide us with a brief synopsis of 12 his educational and job experience as related to the Nuclear field.
13 Mr. Bennett.
g 15 BENNETT:
At the present time I've been employed with Metropolitan 16 Edison for five and a half years.
I was hired as an instrument man g
first class.
I've been a maintenance foreman for a little over two 18 years now.
Prior to that I was in the U. S. Navy RT r.ine and half years as an electronics technician trained as a reactor operator.
21 RESNER:
22 Ok, thank you, Mr. Bennett.
Mr. Creswell at this time has Some questions he'd like to a ask.
24 25 l
3 1
C,F ESWELL:
This is Jim Creswell speaking.
Skip, I'd like to go back 2
to the day of March 28th at the time t.hich you first came on site.
3 Can you tell us what time you arrived and what you did when you arrived 4
at the site?
5 BENNETT:
I arrived at the site that morning shortly before seven 6
7 oclock and proceeded through the security building and we were told g
that there was an emergency over at Unit 2, to muster our people in the auditorium in the service building.
g 10 CRESWELL:
Unit 1 or Unit 2, Skip?
g 12 13 14 CRESWELL:
Ok.
Who was in charge in the security...in the auditorium, Unit 1 auditorium?
17 BENNETT:
To the best of my knowledge, I guess the senior man there would have been Pete Snyder.
20 CRESWELL:
O k.
You mentioned there had been an emergency declared.
What time of emergency, was it a site emergency or general emergency?
23 BENNETT:
I'm not really sure what was declared at that time.
24 25 A
4 1
CRESWELL:
After you assembled in the Unit 1 auditorium, how many 2
people approximately are there in that building at that time?
3 4
BEhgT:
The majority of the workers start work at 7:30.
So around 5
7:'50 the auditorium was getting fairly...I'd say there was 100, 120 6
people.
7 CRESWELL:
O k.
What's the next thing that happens after you get in 8
the auditorium?
g 10 BENNETT:
11 I was there approximately an hour, before I received a call from Doug Weaver over in Unit 2.
And he had asked me about the remote 12 multiplexer for the computer, because the incore thermocouples had 3
gone offscale high on the computer.
g 15 CRESWELL:
He asked you about...
17 BENNETT:
...the location of the remote multiplexer.
g 19 CRESWELL:
What did you tell him?
21 BENNETT:
I told him that it was down there and he suggested that I come over to Unit 2 to take the readings with a portable instrument.
24 25 l
l
5 1
CRESWELL:
Did you bring an instrument over from Unit l?
2 3
BENNETT:
No, we had had the instruments up in the Unit 2 instrument 4
shop.
5 6
CRESWELL:
About 8 o' clock Doug called you and asked you whe:9 the 7
remote multiplexer was and then you went over to Unit 2 Control Room?
8 g
BENNETT:
Yes, I did.
10 CRESWELL:
Was there anybody with you?
11 12 BENNETT:
Yes. Bob Gilbert.
13 14 CRESWELL: Bob Gilbert. Did you direct Bob to go over there or did Mr.
15 Weaver ask for him?
17 BENNETT:
Mr. Weaver asked for both of us.
8 19 CRESWELL:
What's Bob's job title?
21 BENNETT:
He's a maintenance foreman, nuclear also.
23 CRESWELL:
24 O k.
So about what time would you have gotten over to the Unit 2 Control Room?
25 t
6 1
BENNETT:
We arrived over at the Unit 2 Control Room shortly after 8 2
o' clock, about probably about ten minutes after eight.
3 4
CRESWELL:
Ok.When you arrived in the Control Room, what sort of 5
conditions did you find in the Control Room?
6 7
BENNETT:
An extreme amount of personnel from what I'm used to seeing 8
in the Control Room.
9 CRESWELL:
How many people would you estimate are actually at the 10 11 Panels themselves, manipulating controls?
12 BENNETT:
At the panels themselves, I'd say there was probably no more 13 than four people actually manipulating.
p 15 ere ere oGer people standng in ne area of t,he conkol 16 panels?
g 18 BENNETT:
In the area of the panels but not in the area of the console, g
that I can remember,...back at the vertical panels in the Control Room at the computer console.
22 CRESWELL:
Ok, what were they doing?
24 25 l
7 1
BENNETT:
Most of them were observing instrumentation in the Cantrol 2
Room.
3 4
CRESWELL:
How many people were standing in the rear of the Control 5
Room?
6 7
BENNETT:
I really couldn't guess.
I'd say there was more than is 8
normally in the Control Rocm for a morning operation.
9 CRESWELL:
10, 20, 30.
10 11 BENNETT:
Maybe 10 or 15 people.
12 13 CRESWELL:
14 So there would have been between 15 and 20 people total in the Control Room at that time?
g 16 BENNETT:
Approximately, yes.
g IS' CRESWELL:
So after you get there I guess Mr. Weaver gives you some g
instructions, is that correct?
21 BENNETT:
Yes, he did.
He had told me that the incore thermocouples had gone offscale on the computer.
They're only characterized up to, I believe 700 degrees Fahrenheit.
At that time I guess I'd spoken to Mr. Weaver and Mr. Porter, he's the instrument engineer, gave me a
8 1
brief plant status and the fact that they had the trip.
At the present 2
time there was no reactor coolant pumps running.
They thought that 3
possibly they had a bubble in one of the hot legs.
The hot leg RTDs 4
were also offscale high, and at that time we proceeded back to the 5
instrument shop to get a portable thermocouple reader and go down to 6
the cable spreading room.
7 CRESWELL:
Did Mr. Gilbert go with you?
8 9
BENNETT:
Yes, he did.
10 11 CRESWELL:
12 I believe Mr. Wright and Mr. Yeager were also involved in these measurements.
When did you first see them?
13 14 BENNETT:
I believe when I went back to the instrument shop.
I saw 15 Mr. Wright, I believe Mr. Yeager had already started down for the 6
cable room.
g 18 CRESWELL: Mr. Yeager had already departed.
g 20 BENNETT:
Yes.
21 22 CRESWELL:
Ok, so you and Mr. Gilbert walked back to the I & C shop.
23 You see Mr. Wright there and Mr. Gilbert is already...Mr. Yeager has already departed for the cable room?
25 l
9 1
BENNETT:
Yes.
2 3
CRESWELL:
Ok, you get the...what is this a fluke... thermocouple 4
reading?
5-BENNETT:
Its a fluke thermocouple reader.
6 7
CRESWELL:
Ok, alright, so does Mr. Wright accompany you and Mr.
8 Gilbert down to the Cable Room?
g 10 BENNETT:
Yes, I believe he did.
12 CRESWELL:
Ok, and you find Mr. Yeager already there.
14y BENNETT:
...already there and I can't remember if Mr. Porter was there at that time or shortly thereafter.
17 CRESWELL:
Had Mr. Yeager already taken some leads loose?
19 BENNETT:
No, he hadn't loosened any leads.
He had the cabinet door unlocked on the remote multiplexer for the computer and had identified 21 the computer points by wire marker as to where we wanted to take the 22 readings.
23 24 25
10 1
CRESWELL:
Ok, so he had some infoi nation with him to indicate where 2
the leads.could be found?
3 BENNETT:
I believe he was told where they could be found.
When we 4
5 went down I also took the point identification book for the computer.
6 CRESWELL:
Ok, af ter the four of you are assembled there around the 7
multiplexer, what's the next thing that happens?
8 9
BENNETT:
I believe we set the thermocouple reader up to read the type 10 K thermocouple.
At that time, we weren't sure whether we could hook right on to the computer with the field wires terminated or not.
We decided it would be best to lift the field wires and hook them directly to the thermocouple reader.
15 CRESWELL:
O k.
16 17 BENNETT:
I don't remember which computer point it was that we read first.
It was chosen more on a ease of access to the field wiring.
20 Turned tha thermocouple reader on and that thermocouple read somewhere between two thousand and twenty one hundred degrees Fahrenheit.
21 22 CRESWELL:
The first one?
23 24 25
11 1
BENNETT:
The first one.
2 CRESWELL:
Ok, about what time would you estimate your making the 3
4 first reading?
5 BENNETT:
I'd say it was probably around 8:20 to 8: 1!5.
6 7
CRESWELL:
Ok, so what's the next thing that happens?
8 9
BENNETT:
After that we decided to read an additional thermocouple.
0 Again I can't remember exactly which computer point thermocouple it was.
We, in that case had lifted the field wiring, hooked it up to the thermocouple reader.
I remember that it didn't read as high as the first one we read, that it was reading higher than what would be normally expected.
At that pont we decided to try and I think we reterminated that set of field wires, read it again and saw that there was no affect from the computer back to our thermocouple reader and decided that we could read the rest of them with the field wires 18 terminated.
19 20 CRESWELL:
You say there was no effect?
21 22 BENNETT:
I wasn't sure whether we'd see an effect from the open input 23 testing on the computer or if we had any parallel paths that might 24 change the millivolt readings on those termir.als.
25
12 1
CRESWELL: When you take the field wiring loose, does the computer 2
have an input to deal with at that point?
3 4
BENNETT:
No, it doesn't.
5 CRESWELL:
So you reterminated these two...
6 7
BENNETT:
No, I reterminated the one...that first one we never did 8
reterminate until we had completed a set of readings.
g 10 CRESWELL:
O k.
What's the next thing that happened?
g 12 BENNETT:
At that time, I decided that due to the difference in reading 3
between the first two thermocouples that we looked at, that it would be beneficial to take a complete set of readings.
The thermocouple 15 reader is not really a convenient piece of test equipment to use to take multiple readings in a situation like that.
So I decided to have the technicians take a complete set of millivolt readings on all the incore thermocouple cables.
20 CRESWELL:
At this point in time, before you decided to use the...like an additional voltmeter, you had only taken two readings?
22 23 BENNETT:
Two that I'm sure of, possibly three.
24 25 l-
13 1
CRESWELL:
Ok, now is Mr. Porter apprised of the results of the first 2
readings?
l 4
BENNETT:
I really don't remember.
5 CRESWELL:
Do you recollect any of the technicians making any comments
~
6 7
about the results of the first readings?
8 BENNETT:
There was some concern or disbelief on the thermocouple at g
that time.
10 11 CRESWELL:
Was there any discussion that the high temperature readings 12 indicated that the core was possibly uncovered?
13 14 es, I believe that did come up in our conversations as we 15 were down there taking our readings.
17 8
But you can't recollect whether Mr. Porter was there at CRESWELL:
that point?
20 BENNETT:
I believe he was down there at that point.
I can't remember 21 if he was there when we took the reading or when we on the second or 22 third one had started in.
I know he did come down to the cable room 23 prior to us completing the complete set of readings.
25
I 14 1
CRESWELL:
O k.
So after you make these initial readings you make the 2
decision that it would be easier to make readings with additional 3
voltmeter.
4 5
BENNETT:
Yes, it would rather than disconnect the field wire for each 6
individual computer point.
7 CRESWELL:
Was there any discussion that there might be an error in 8
g the calibration of the thermocouple reader?
10 BENNETT:
No, it's a piece of calibrated test equipment.
It was well g
within its calibration cycle and it's a fairly new piece of equipment.
13 CRESWELL:
So you made the dec.!sion to use a digital voltmeter :;olely on the basis of its being an easier instrument to read the...
16 BENNETT:
It was easier to get a set of leads just regular test leads for the digital voltmeter, rather than Type K lead in wire for the digital thermocouple reader.
Thermocouple reader, you would have had tn loosen the screws, got good contact down under the each input, whereas with the voltmeter its just a set of test leads.
22 CRESWELL:
Ok, so what happens, do you send ::cmebcdy up::tairs to get 23 this...
24 25
15-1 BENNETT:
No, there was a digital voltmeter down in the cable spreading 2
room at that time.
3 CRESWELL:
So is Mr. Yeager, Mr. Wright, yourself or Mr. Gilbert still 4
5 present in the areas when you start making the second set of measurements?
6 BENNETT:
Yes we were.
7 8
CRESWELL:
Do you already have all of the input information that you g
10 11 BENNETT:
Yes, I had a L & N thermocouple table that I got from my desk prior to going down, the computer point identification book listed terminal or cabinet row terminal numbers computer. point numbers, the wire markers themselves are marked as to the computer point.
16 CRESWELL:
Ok, so you start making a second set of measurements now which ones do you choose to measure the second time around?
19 BENNETT:
We went in numerical order for the computer point numbering system and went completely through the incore thermocouple.
22 CRESWELL:
Did you go back and reverify using the digital voltmeter 23 and suitable conversions that the thermocouple reader had?
24 25
16 1
BENNETT:
Yes, we had on...not on every point.
I believe on one or 2
two of the points, we had said that... assuming an ambient temperature 3
of approximately 75 degrees I think, between 70 and 75 degrees, we 4
were coming real close to what the digital thermocouple reader had said.
Some of those inputs were.
5 6
CRESWELL:
The ambient temperature had the effect on the cold junction 7
correction.
8 9
BENNETT:
It had the effect on the cold junction correctirn, you would 10 have had to have applied to the tables to get the thermc;.;uple temperature.
g 12 CRESWELL:
O k.
About what time would you estimate that you completed the second set of measurements?
14 15 BENNETT:
I would say it was approximately 8:45, 8:50.
17 CRESWELL:
Was Mr. Wright, Mr. Yeager, Mr. Gilbert, yourself, all still present at the time you completed the second set of measurements?
20 BENNETT:
I believe they all were present, yes.
21 22 CRESWELL:
Was Mr. Porter present whenever you completed the :;econd 23 set?
24 25
17 1
BENNETT:
That I don't remember exactly.
2 3
CRESWELL:
How did you record the data that you were taking off?
4 5
BENNETT:
I had used a computer point identification book, as we were 6
using that to check rows terminal numbers.
I was writing them in next 7
to the computer point in the book.
8 CRESWELL:
Do you recall that any set of measurements were copied down g
10 n say a scrap piece of paper?
11 BENNETT:
Not to my knowledge, no.
12 13 C_RESWELL:
Do you recall any thermocouple readings up to the rcnge of p
15 16 BENNETT:
No, I don't recall really what any of the readings were Other than the first one because it was extremely higher than what I had expected to see.
g 20 CRESWELL:
After the second set of measurements was taken, do you recall any discussion, any further discussion of the core being uncovered?
23 BENNETT:
Yeah, I believe that came up as a topic of discussion and we, I can't remember who said what,...there was no formal statements 25
18 1
made down there at that time, just the technicians, and myself and Mr.
2 Gilbert talking.
It seemed...I was under the impression that the core 3
had possibly been uncovered.
4 5
CRESWELL:
Did you make a statement to Ivan Porter to that effect?
6 BENNETT:
Yes, I believe we did when he was down there and we had 7
8 pretty much taken to believe the first reading we got up around 2000 degrees.
g 10 CRESWELL:
What was his response?
12 BENNETT:
I don't really remember what his verbal response was.
I 13 have a feeling that he was more or less in agreement with everybody else that was down there.
We had possibly uncovered the core was the only way we could see that you could have obtained temperatures of that magnitude.
18 CRESWELL:
So after you complete the measurements in the range of 8:45, 8:50 what happens then?
21 BENNETT:
Myself, Mr. Gilbert, Mr. Yeager and Mr. Wright proceeded up to the Control Room.
I believe Mr. Wright and Mr. Yeager then returned 23 to the Unit 2 instrument shop.
I had placed the computer...the point 24 identification book back on the computer console.
I had informed Mr.
25
19 1
Porter that there was several thermocouples that were extremely hot in 2
the neighborhood of 2000 degrees Fahrenheit and then I believe that 3
was about it I think I took the time...at that time I looked at the 4
post trip re...not the post trip review...the sequence of events that 5
had typed out of the computer that morning and then myself and Mr.
6 Gilbert returned to the Unit 2 instrument shop.
7 CRESWELL: What did you find when you reviewed the sequence of events?
8 9
BENNETT:
I remember that the first thing on the sequence of events 10 11 was the loss of the condensate pump...I don't remember which one 12 f 11 wed by the loss of the B feed pump then the A feed pump and then a turbine trip followed shortly by a reactor trip on high pressure 13 followed by what I thought was a short period of time for a plant g
trip, the low pressure injection...high pressure injection, ES actuation.
15 16 CRESWELL:
Ok.
Where physically did you go after you got through reviewing the alarm typer output, is that what you're...?
19 BENNETT: Yes, It is.
I returned to the Unit 2 instrument shop.
21 CRESWELL:
What did you do there?
23 BENNETT: We didn't do too much of anything.
We were only there for 24 approximately ten minutes.
I believe at that time Mr. Weaver, Mr.
25 i
l l
20 1
Kalenevitch, who is a maintenance foreman, nuclear, myself, Mr. Gilbert, 2
the two technicians that had been down in the cable room with us, I 3
believe there was a couple more technicians, instrument technicians up 4
there at that time, had gone back to the shop and we weren't there 5
m re than maybe ten to fifteen minutes when they said that all unnecessary 6
personnel should evacuate.
At that time it was decided Mr. Weaver 7
would stay for the instrumentation and the rest of us proceeded over 8
to the service building to go through the check point which was set up in the hallway.
g 10 CRESWELL:
You said Mr. Gilbert would stay there to work.
g 12 BENNETT:
No, Mr. Weaver would stay there to work.
3 14 CRESWELL:
Ok.
Did you have any knowledge of when the digital voltmeter 5
was hooked up to the "A" loop... hot leg?
17 BENNETT:
No, I don't.
19 CRESWELL:
To your recollection Mr. Wright didn't leave during any period of time that you were taking the measurements to go perform an 21 1
evolution like that?
22 23 BENNETT:
Not that I can remember.
24 25 1
l
m 21 1
CRESWELL:
So you received directions from Mr. Weaver to leave the 2
site, is that correct?
3 BENNETT:
Yes, I had.
He had said that he would stay and I don't 4
5 remember if he kept a technician or if he kept misre than one technician.
6 CRESWELL:
So what happens on your exit of the site.
How do you go 7
" " 9 "9
8 9
BENNETT:
We proceeded to the Unit 1 service building.
They had 10 health physics personnel down by the main entrance to the service building and everjene was being frisked as they exited the building were told to go over to the 500 KV Substation.
14 CRESWELL:
What happened when you got over to the 500 KV Substation?
16 BENNETT:
All the cars were brought inside the fence at the 500 KV Substation and health physics had again set up, I believe, three or four monitoring stations.
All personnel were frisked again.
As we exited the Substation the vehicles were frisked again.
20 21 CRESWELL:
Were you or anybody with you contaminated?
22 23 BENNETT:
No, not that I can remember.
24 25 h
22 1.
CRESWELL:
Ok, At this time I'd like to ask you if you have any 2
comments that you would like to make of any nature?
3 4
BENNETT:
No, not really.
I believe anything I'd have to say would 5
just be pure conjecture on my part.
6 CRESWELL:
Do you have any recommendations involving what you've seen 7
g in the accident for improvements in the future?
9 BENNETT:
Yes, I believe the utility company needs better lines of 10 communication with the outside world.
It became extremely difficult g
in that time period and shortly following that to get a call out of the island, get a call in...even to the Observation Center or from the 3
Observation Center to the island, became extremely difficult.
I was e
e ne ay n
ae n
, we'd set up shift work, 15 I was to report back at three o' clock for the three to eleven shift.
l When I arrived I was told ',o take, I believe it was four technicians in with me and give a note briefing as to plant status, protective clothing required at any point or different points on the island.
I didn't like to do that after knowing the severity of the accident or where it could have been in the time period that I had not been on th-21 island.
I thought that I should have been briefed as to plant status 22 and what was required to maintain any mobility at all in the plant.
23 24 25
23 1
CRESWELL:
Were you sent int areas that had high radiation f ilds?
2 3
BENNETT:
No, I wasn't.
We were told to go up to the Unit 2 Control 4
Room.
At ti:at time I didn't know where the high radiation fields S
w uld be, other than...I assumed the auxiliary building.
6 CRESWELL: Where did they send you and what type of jobs did you get 7
involved with?
8 9
BENNETT:
That first night, the biggest thing was setting up an additional 10 radio in the Control Room for communications between the Observation g
Center and the Control Room.
13 CRESWELL:
Now that night was the night of...?
15 BENNETT:
That would have been the night of the 29th.
17 CRESWELL:
18 What was the purpose of this radio?
19 BENNETT:
It was to establish additional radio frequency ability i
20 between the Observation Center and the Unit 2 Control Room.
21 22 CRESWELL: Where d:d you get the radio?
23 24 25
.1
24 1
BENNETT:
I'm not sure where the radio came from. It was given to me 2
when I got on shift along with the N-antenna, to mount up on the 3.
turbine building roof.
4 5
CRESWELL:
What frequency did the transmitter operate at?
6 BENNETT:
I believe its 37.54 megacycles.
7 8
CRESWELL:
Is this covered under your normal license?
g 10 BENNETT:
Yes, it is, I believe, it's a system radio.
g 12 CRESWELL:
Ok, I have no further questions.
14 RESNER:
Resner speaking, thank you for your time, Skip, and this 15 concludes the interview.
The time now is 9:35 a.m. Eastern Daylight Time.
17 18 19 20 1
21 22 23 24 25
.