ML19199A230
| ML19199A230 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 04/04/1979 |
| From: | NRC COMMISSION (OCM) |
| To: | |
| References | |
| REF-10CFR9.7 NUDOCS 7904060453 | |
| Download: ML19199A230 (87) | |
Text
i esif; [ [SIh. It 3 g
j },bu,3 yfik,
~
yg ;.
NUCLE AR REGULATORY COMMISSION IN THE MATTER OF:
PUBLIC MEETING STAFF BRIEFING ON GENERIC IMPLICATIONS IN THREE MILE ISLAND INCIDENT Place.- Washington, D. C.
Dato -
Wednesday, 4 April 1979 Pages 1-86
--z y
Tei.eren.:
(202):47 37:o ACE - FEDERAL REPORTERS, INC.
QA; 2'23 Official Reponers 144 North Cecitel Streer
- 11. O,NO Wcshingten. D.C. 20C01 N ATIONWIDE COVERAGE - D AILY
(
g
\\
.s.
.i e
DISCLAIMER This is an unofficial transcript of a meeting of the United States in the Nuclear Regula:ory Comission held on 4 April 1979 Ccmmission's effices at 1717 H Street, d. W., Wasnington, O. C.
The meeting was c;en to puclic attendance and observa:icn.
This transcript has not 'ceen reviewed, corrected, or edited, and it may contain inaccuracies.
The transcript is intended solely for ceneral infor :a'ticnal curposes.
As rovided b.v 10 CFR 9.103, it is not part of the femal or infor: al record of decisica of the matters discussed.
- xeressions or coinicn in
- his transcri :: de not necessarily reflect final deteminaticns or beliefs.
.:0 oleading or other cacer may be filed with the Commission in any proceeding as the result of cr addressad to any statement or argument contained nerein, except as the C =ission may authorize.
e
{ {
A. /.[.
i 2!
9 1
UNITED STATES OF AMERICA j
I 2l NUCLEAR REGUI.ATORY CC.T4ISSICN I
I.
i 3'
PUBLIC MEETING i
I i
4 i
STAFF 3RIEFING ON GENERIC DfPLICATIONS IN i
l Si i
THREE MILE ISLAND INCIDENT i
6 'l l
7 8
Room 1130 9'
1717 H Street, N.W.
Washington, D.
C.
10 Wednesday, 4 April 1979 11 i
The Cc= mission met, pursuant to notice, at 1:10 p.m.
12 BEFORE:
l 13,
DR. JCSEPH M.
HENDRIE, Chairman i
i 14,
VICTOR GILINSKY, Cc=missioner 1
15 '.
.1 RICHARD T.
KENNEDY, Commissioner 1l 16 j ll PETER A.
BRADFORD, Cc=missioner 17 ;
JOHN F. AHEAPliE, Commissioner 13 :
f PRESENT:
19 Messrs. Sickwit, Case, Chilk, Davis, Eisenhut, Jordan, 20!
I Kellev_, Moselev_.
21 'j
'i 79
- 1 Sa.',
J i
22 11 M e ec tr al R e00f *f r5. I nc.
E
.* t I
8 f
R '3 79 2 -
i 3
IELT"ER
~15 2 mtel i
l 1l
.P _R O.C _E E.D I N _G.S I
2 (1:10 p.m.)
l i
1 3'
CHAI??A'i HENDRIE:
The Comnission will comc to o rder, l.
4 please.
j i
i
'f i
5:
We are meeting this af terncon to have a briefing i
i i
i 1
6i from the staff with regard to other plants using the Babcock &
i 7'
Wilcox nuclear s team supply system.
Our concern relates, 8
obviously, to possill.e difficulties in the other units.
That 9
has been a of
'me concern to us.
i 10 !
it you're the leader of the party?
11 !
9e.
C' re.-
sir.
12 l CFAI;l:?.'T H. DRIE :
By way of background, we migh t 13 ask John Davis to simply summarize for :s the actions that i
14 ) have been taken here to date with regard to getting a resident i
15 l inspectcr onto the other sites, thos e that didn' t already have i
16
- one, i
i 1
17!
MR. DAVIS:
Inspectors have been assigned to each 18 I site with an operating Sabcock & Wilcox-designed nuclear power I,
19 plant.
Ne had resident inspectors already assigned to two of 20 the five sites, Arkansas 1 and Oconee 1, 2,
3.
It just happens,
.l 21 1 however, that the resident inspector at Ark 1 was being t
22 j replaced because of a pronation, and de inspector a: Oconee
!i 23 4 was assisting at the Three Mile Island accident site.
o 1
24 a Inspectors were dispatched by Menday, April 1, so ac n.
- my2c.,p
^25) that all five sites are provided with resident-ype
.i
,- l
e.2 4
i 1
1 inspection coverage as of now.
2 CHAIRMAN HENDRIE:
Very good.
And you have a i
i 3i bulletin out?
1 1
l 4
MR. DAVIS:
We have a bulletin issued on April 1 i
l 5
that was transmitted by telecopier from the regional offices f
6' to four o f the sites.
For the fif th, we had transrission 7
difficdlties with the telecopter and hand-carried the bulletin I
3 to the licensee.
i Regional management and supervision has discussed 9
I 10 the bulletin by telephone wi *k licensee management.
i l
11 'l CHAIRMAN HEMDRIE:
Okay.
Edson, I know that in 1
12 !
view of the operational situation at Three Mile, the need to i
l 13 l succort the larce tr hnical staf f down there witn a tull-scale I
I 14 l effort at the Bethesda Incident Response Center, tha t there l
15 have been limited staff rescurces.
And also, it's early in i
16 !
the event to fully evaluate all of the things that have i
i 17' han.cened.
i l
18 l So that I'll recognize that we deal en a best i
t I
19 knowledge at the eccent basis.
Why don't you go ahead, th e n,
20 m and outline for us what we knew at this coint.
21 MR. CASE:
All right, sir.
Chank you very nuch.
I O
22 ?
as you know, we are here today to provide you with i
1 22 9 a status report of our previous, current and planned s taf f
,1 24 future actions concerning the generic aspects of the Three E *C tr 39 S f OQ r ff f1. I nc..
It ' A s'2f,;t O
Mile Island accident.
As we will discuss in ore de:ni by
e3 5
I Darrell Eisenhut and Ed Jordan, dhese actions include:
2 First, development and initial evaluation by che l
3 staf f o f the preliminary chronolog. y of crincipal events that I
1 4'!
occurred during the initial certion of the Three F4 7 = 7sland i
5 accident; 6'
Second, as has already been discussed, issuance of a 7i bulletin by the staf f on Sunday, April the 1st, to all operat-i 6
l 1
3!
ing plants having a 3&W-designed reactor, directing those i
9I licensees to reviea and modify as necessary oceratinc. croce-10 l dures related to the Three stile Island accident; I
11 i Third, initiation of a staff study and evaluation of 12 !,
the response o f S&W-designed reactors to feedwater transients ;
h 13 i Fourth, planned issuance of a follow-up bulletin i
i 14 ;
within the next day or so that will provide licensees of these 15 '
3&W-desivned reactors with the preliminary chronology of 16 principal events during the Three Mile Island accident, and ll 17 l with specific instructions regarding plant operation concerning 13 the maintenance and operation of the auxiliary feedwater 19 '
syster, with instructions regarding the use of pressurizer 0
level ins trumentation and ecergency core cooling sys tem during 4
21 reactor transients, and with ins tructions regarding containment y
6
,-" d, isolation during ICCS operation.
l 23,
We. clan to contin"a "a
develocrent and the inves ti-1
.,a gation of the accident secuence and plant operator response
..tr al R eOO rff r5. I nc.,.
25 ! during the Three Mile accident, and continue Ehe staff study 11 2.28 i
e.4 6
i 1
I!
of the response of the S&W reactors to the feedwater j
l i
j l ~
i
.I i
l i
3' And lastly, we P an to continue with whatever further!
l 1
t staf f actions are necessary, based on these studies, by bulle-
)
I i
5' tin or other communications with licensees, based on the 6'
continuation of these studies in the future.
7 It was the staf f 's conclusion, based on the collec-3 tive actions that have been taken and are currently underway, I
9 that operating plants with B&W-designed reactors could continue 10 in operation without undue risk to the heal th and s af e ty o f 11 i; the public.
12 '
Ncw, I'll turn it over to Darrell, who will walk you i
I3 I through these various actions that we are takir.g and have
,i e
i M
i 1
taken in some more detail.
Darrell?
t i *c '
- iR. HISEU'dUT:
Thank you.
16 To lay a framework on the actions that we are taking 1
l
i presentiv what I would like to do is walk throu h the scenario
.r j-.
of events as we understand them at this time, recognizing that
- 1 19 1 some of de events ray be later shcwn to be scnewhat in error.
I a
C u.n,.r 2. v.a..,.. L..D.or=
r.s. e.,.,,
., s.=..i _- u,,
s I
,_.,n_..u.,
.i -
m..
21 y had occasion to comment this morning at a hearing, dat th e
,, l prinary effort of de agency has been concentrated on dealing 1
" !. with this situation and trying to preser re a safe cond. tion i
2" with the clant Jfral 4 900rifft. IM
~
down there, rader dan carging out any sort c
of extensive investigation.
So I think we will all recognize li'2?9
l e6 7
1 1
that necessarily the chronologv. and exactly what haccened is u, i-2 very preliminary view at this time.
There will be a full 1
3i investigation by Ehe NRC as soon as we are able to do it.
But i
i i
4l the first thing to do is to as s ure the good, s table condition i
i i
o f the clant.
5 i l
6' Please go ahead.
c 7l MR. EISEUHUT:
Thank you.
I On Ehe day of the accident at Three Mile Island, i
8 I i
l 9l some time b e tween 3 : 0 0 and 4 : 00 a.m.,
there was maintenance t
10 !
being performed on the main feedwater system.
To give a little i
i 11 better perspective of what this is and the locations of these,
12 l we have a viewgraph.
If I could have the first viewgraph, I
13 !
please.
I.
i 14 l (Slide. )
i i
15 l This is a very simple sketch of a S&W reactor.
And i
16 '
you will notice the norral feedwater sys tem.
17 At about 4 : 0 0 a.m., there was a loss of a condensate 18 pump and the loss of a feedwater pump, which resulted imme-19 i diately in a tacine trip.
For the sake of che discussion 20 i going thro ugh, I will call that time zero, to fix all following 21 - even 5 within our approximate time, as we understand the.m.
1 1
22 h At time about 3 to 6 seconds, the elec tromagnetic a
1 relief valve on the cressurizer o.nened to relieve reactor 23 -J i'
24 coclant system pressure.
We believe it was abcut 2255 esi.
.5cerai Aeoorters, Inc. {
25l The pressure relief valve is indicated on the slide at the to p,
1 11 230 I
A.
8 l
o 4
1 1
on the right, j -
u 2l At about 9 to 12 seconds into the transient, the l
3' reactor trip on high reactor coolant system pressure, which l
I 4'
was about 100 psi higher, that is, abou t 2355 psi.
i S
At about 12 to 15 seconds in to the trans ient, th e l
j i
I 6'
reactor coolant sv. stem cressure was decav. ing, as it should 7l have been, and was down to about 2200 psi.
It is at this I
t 8
point that normally one would expect the pressure relief valve 9l to have closed.
I i
10 '
i At about 15 seconds, the reactor coolant system i
II hot leg temperature peaked out at 611 degrees Fahrenheit, at 12 about 2150.counds cer sc.uare inch.
That 's arout 4 50 counds 13 above the saturation.
14 At about 30 seconds into the transient, we note 15 from the clant information on the recorders that all three i
16 l auxiliary feedwater pumps were running at pressure.
You will t
6 17 l see only one auxiliarv feedwater cuma labeled emergency l
i 18 l feedwater pump on this slide.
There are actually three such i
19 d
- c. umn. s.
Pumes 2A and 23, as th ev. are denoted, actually had
- 0 started earlier to come up to speed and were actually running, i
we believe, some seconds earlier.
kowever, it is at this ej 4
,, i o.coint that no flow was in"ected into the feedwater system,
,,o
-- ; because the discharge valves to all three trains were closed.
i At about T ecuals 60 seconds, the cr ssuriner level Fectf31 ReOCrters,Inc.
~
l 9C i indication becan to rise racidiv..
1.4
,7 9 A v..
s f
i i
- e 7 9
l i
1 CFAIRMAN HEUDRII:
60 seconds?
.I 2l I
MR. EISENHUT:
About 60 seconds.
l 3!
COMMISSIONER 3RADFORD:
Darrell, this discharge i
I 4,
valve should have been ocen as a matter of oceratinc oractice?
i 5l l
MR. EISENHUT:
Yes, it shou"d have.
The three i
I 6
auxiliarv feedwater curn. valves to those three trains should 1
I 7l have been open and should have remained open.
We have i
i i
8 i
actually a technical specification on this plant, as we did I
9 on all plants, that says that the valve into the sys tem should 10 have been open at all times.
i II I l
It goes on further to sav -- Saat is, if the system 12' is un at oressure above 800 asi.
It goes on to say that if I
13 !
that valve -- one of those valves can be closed for a certain l
I 14 '
finite period of time on the order of 48 to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, if it i
15 is not restored and that train is not back operable, then in i
16 fact the plant should be shut down.
So there is a technical 17 specification.
la [
COMMISSICMER AHEARNE :
Jus t one valve?
I9 '
MR. EISENHUT:
Yes.
It varies.
If two out o f th e 0
three trains are inoperable, it's a matter of how fast you 4
21 l have to shut the plant down.
i CHAIRMAN HENDRIE:
The s eco ndary sys te.'"
then what, 1
1 23 ]1 backs agains t check valves in the discharge of those pumps?
MR. EISIUHUT:
There are valves that coen auto-Etceral ReOQrtffs. inc.,
- 5 i matically from the system n
t at says, tne enc'neerec-s ar e ty i
14 Ono A
A. 04 1
llh l
mte 8 10 1
1 electrical system Snat says to open ano ther valve.
So that j-i 2l there is actually two valves in series. The valve that was 3
closed is the valve that should have been actually open.
i 4-There are, as you say -- I do n ' t remember whether it was j us t l
l i
5I check valves, check valve and gauge valvec, but there are t
i 6',
several valves in the secuence.
l 7,;
CHAIPl!AM HEUDRIE:
Probably a combination.
\\
^
i 3
MR. EISENHUT:
I think that 's right, yes, sir.
9!
COM'iISSIONER GILIMSICI:
Do you know how long they 10,
were clos ed?
Il MR. EISENHUT:
We're not sure exactly.
However, we I
i 12 do know there had been some testing maintenance that had been i
i 12 ;
performed on these valves within the two wecks before the 1
i 14 i e ve nt.
And we also know th at the valve in the control room i
15 was tagged, as is their usual habit when valves are in fact --
16 are undercoing tests and rain tenance.
'Ia 17 {
The plant leg clearly illus trates Saat in fact thes e i
18 i va'.ves had been tes ted and undergene maintenance and were i
19 '
closed.
20 CO!C1ISSIONER AHEARNE:
The le' indicates that the_v 21 l were closed?
7 22 j
!R. EISENEUT:
'i e s.
1 23 l 24 J wai n. corms. inc.
11 233
- s. :
CR 37,92 11 IELTZER: j'wb
- 3 1
At about the same time -- that is, T equals 60 2
seconds or 1 minute -- and from this point on,. the figures I 3l will giva you in time are in terms of minutes -- at approxi-1 i
4' mately T equals 1 minute, the steam generators A and 3, the 5
secondary side level was very low.
This is because of course 6
no feedwater, and they were beginning to dry out over the next 7
couple of minutes.
,8i At a.'out T equals 2 minutes, the emergency core i
i, 9;
cooling system high pressure injection initiated at about j
l 10 !
1600 osi, as designed.
i i
i i
i 11 !
MR. CASE:
Initiated automatically.
I 12 '
MR. EISENHUT:
Yes.
l 13 ;
Over the time from about 4 minutes into the i
14 l transient to 11 minutes into the transient I
I 15 '
COIOiISSICNER KENNEDY:
Is that 16007 t
16 '
MR. EISENHUT:
Yes, sir.
17.
Over the period of time from about 4 minutes to t
18 l 11 minutes into the transient, the pressurizer level went off I
19-scale high.
During this period of time, one high pressure 20 -
injection pump was manually tripped off-line at about 4 minutes 21 and 30 seconds, and the second high-pressure injection pump 22 )
was tripped off-line at about 10 minutes and 30 seconds.
i 23 3 COM:1:SSICNER SRADFORD:
Why?
11_434 n
24 il MR. EISENHUT:
We do not know.
Ceceral Reporters. Inc. l 25l CC:01ISSICNER KENUEDY :
They were tripped manually?
.i
1-2 jwb 12 1
MR. EISENHUT:
They were manually tripped.
One 2
could infer that with the pressurizer level reading off 3
scale high, it would tell an operator that the pressurizer had 4!
been filled up.
And he may, because of this situation, he 5
may choose to trip the high-pressure injection pumps.
i I
6{
MR. CASE:
And as we'll get to later en, the l
7 instructions we' re considering that we plan to put in this l
3 new bulletin will deal with this situation.
We'll give you 9
the scecifics on that later on.
1 l
!i 10 '
4R. EISENHUT:
At about 6 minutes into the I
11 I transient, the reactor coolant system was flash ng the steam-- l 12 COMMISSIONER KENNEDY:
6 minutes?
l l
l 13 MR. EISENHUT:
At abouu 6 minutes, it began flashing l l
14 l as the pressure bottomed out at about 1350 psi.
The hot leg i
i l
l 15,
temperature was at about 585 degrees F.
I 16 At about 7-1/2 minutes into the transient, we have 17 ;
indication that the reactor building's sump pumps came on i
i la,
automatically.
I 19 '
COMMISSIONER AHEA.*UTE:
What is the meaning of that?
1 1
20 MR. EISENHUT:
You will see later on how this 21 l comes into play.
We have -- and I gueso I should say, at this i
i 22 po in t, that the sequence of events that I'm going through is 23 3 the sequence that we have been able to somewhat collate based 24 upon records from the plant icg, the actual strip chart recorders r
EMetal AGOOrters, Ir**,l 25
.;f instrumentation in the plant, the actual computer printout 44 n s-1
_L.
s ' si d
3-3 jwb 13 1
of the information at the plant, from actual interviews of l
2 plant operators who were on duty during these shifts, and l
i 3
from our understanding of how the plant will respond.
4 COMMISSIONER AHEARNE:
In going through that, then, l
5 you have not yet had the chance to get the operators answers i
l 6;
as to why they turned these things off?
7' MR. EISENHUT:
Not thoroughly, yet.
I 8
COMMISSIONER BRADFORD:
What would have happened if i
9 they had not turned them off?
10 !
MR. EISENHUT:
We haven' t completely analyzed that i
11 situation, but it is certainly possible that you would not 12 have gotten in this severe of a transient.
It would have i
l i
13,
bought you time, certainly, to reinitiate acx feedwater cy l
I 14 ;
simply opening the valves on any one of the three trains.
I 15,
CHAIRMAN HENDRIE:
Darrell, had tne containment 16 isolation signal tripped in the sequence before 7 minutes?
17 l MR. EISENHUT:
Jo, sir.
18 i CHAIRMAN HENDRII-So there had not been --
i i
19 l MR. EISENHUT:
At this point in time, there was 20 not --
- l i
0 CHAIRMAN HENDRIE:
-- radiation levels -- or 21 2,. t. containment pressure signal which would have closed all the q
,, )!
isolation valves.
11 09-~oo l
24
'4R. EISENHUT:
This is correct.
.5eceral Recorters, Irac.
25 CHAIR:!AN HENDRIE:
So that the sump, the containment a
'l
3-4 j.wb 14 I
sump pump was, in effect, free to do the normal cycling to 2
empty that sump.
I presume there was a level instrument on 3,
it that tripced hhat cumo. ?
4 MR. EISENHUT:
Yes, sir.
We understand it auto-I Si matically starts on level.
We also understand that the 6
containment isolates at 4 psi, and you will see a little later 7
on in the scenario how this comes into play.
8 At about T equals 8 minutes, the auxiliary feedwater 9,
flow was initiated by the opening froa the control rocm of the i
l I
l i
10,
closed valves.
l I
11 l At about T equals 8 minutes and 18 seconds, the l
I 12 steam generator 3 pressure reached its minimum 7.nd was turning 13 aro und.
l l
14 At T equals 8 minutes and 21 seconds, steam generatod I
i 15,
A pressure started also to recover, of course following the I
i 16 turning on of the auxiliary reecwater.
i I
i 17' At about T equals 11 minutes, 11 to 12 minutes, I
18 the makeup pumps on the ECC high-pressure injection flow train 19 were restarted manually by the operators from the control room.
20 At about T equals 11 minutes also the pressuriner 21 level indication came back on scale.
22 l COMMISSIONER AHEARNE:
Now that was simultaneous s
I i
23 3 with them starting the ECCS?
o,p~
14.m Aua 24 l MR. EISENHUT:
With the strip chart recordings that Jeceral A eoorte,s, Inc,,
25 j we have, we're going to have to thoroughly study how and exactly i
a-5 $wb 15 1
the time sequencing in detail of when the auxiliary feedwater 2
flow came on, and then the steam generator started to recover l
3i which provided cooling.
I 4
Very shortly thereaf ter, the high-pressure flow 5,
came on, and then the pressurizer level came back on scale.
l 6'
Of course, since that's the point of coming on scale, we' re 7
not sure exactly whe::e the peak turned around.
It was off a
scale for a number of minutes.
9 It was off scale from about 5 minutes to about i
l 1
e-3 10 '
10 minutes, very roughly.
I b-4 11 At about T equals 15 minutes into the transient, i
i I
12 '
the reactor coolant drain quench tank rupture disk blew at l
13 190 psi.
Now this is a large tank where the relief valves I
I la and the safety valves all blow into a tank.
At some plants l
1 i
15,
it's separate tanks.
In this plant,
"-a-a
's one tank.
I 16 l etR. CASE:
hat's inside containment.
~
I 17!
MR. EISENEUT:
Inside containment.
It's commonly i
18 referred to as either the " drain tank" or the " quench tank."
i 19 !
It is equipped with a rupture disk which is designed to blow i
20 ;
at about 200 psig.
21 !
In this plant, the set point was about 200 psig.
t 22 It actually blew, we calculate now, at about 190 psig, due ai 23 lI to the continued discharge of the electromagnetic relief valve a
21 ] on "he pressuriner.
11 MO f er*tf 3l R OCCTTtt1, l nC.
i 25; During tne next perloc c:_ time, : rom acout 20 minutes a
i,
4-6 jvb 16 1
to 60 minutes into the transient, the system parameters were 2
beginning to stabilize at the saturation condition of about 3
1015 osig and 550 degrees Fahrenheit.
I 4
The operators were, obviously from the plant 5
parameter traces --
1 6'I CHAIR WI HENDRIE:
What was the temperature?
i t
7 MR. EISENHUT:
550.
8 CHAIRMAN HENDRIE:
Is that a hot leg?
9 MR. EISENEUT:
It must be on the hot leg, yes, I
I 10 !
sir.
.I I
11 i COMMISSIONER KENNEDY:
Pressure, again?
I'm sorry, i
l 12 '
Darrell.
13 MR. EISENHUT:
1015 psig.
j l
14 CHAIM1AN HENDRIE:
And the time scale on that?
t.
15 MR. EISENEUT:
This was -- they were working 1
l I
1 16 towards this over tne came :rame or 20 to 60 minutes.
i l
l 17 i The next significant event in this scenario is the i
18 l time, about T equals 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and 15 minutes.
i i
19 '
The plant operators tripped the main reactor 20,
coolant pumps on loop S, tripped off both reactor coolant 21 pumps.
At about --
j 11 239 22 CCMMISSICNER 3FADFORD:
..ny is that?
"~
MR. EISENHUT:
- ie are not sure exactly why he 23 d 24 tripped them.
As you will see later in the scenario, or later
. ~.-. _,., s 25 ] in the presentation, one of our items that we are suggesting t'
4-7 j',ab 17 O_
1 to the B&W plants is that in f act in this situation you would 2
keep a reactor pump running in each loop.
3 CCMMISSIONER BRADFORD:
Darrell, at what point in i
the sequence'aow, as you get out into hours wculd they have 4
5 been obligated to lat the NRC know.nat they were having 9
6 problens?
7 MR, EISENHUT:
That's of course a very difficult 8
' action.
I think, as soon as the plant discovers that they I
i 9j have nad a severe ~ransient, and as soon as they have discovered l
I i
10 '
in this situation that they have had f ailed fuel, I believe 11,
they would of course as soon as practicable nc ;fy the NRC.
I l
12 !
COMMISSIONER KENNEDY:
And we're not there yet in I
i 13 this scenario?
14 MR. EISENHUT:
We're probably not there, cecause 15 ;
the people responding to the plant at this point are very l
1 frantically working, as can be seen frcm the system traces, 16 I,
i 17 ;
manipulating a considerable amount of equipment very diligen'.17, 18 !
I might add.
I i
19 ;
Certainly looking at the traces, it appears they 20 were working very, very hard.
21 COMMISSIONER 3RADFORD :
What's going on in the core i
i 22 h towards the end a f that firs hour?
11 240 91 MR. CISENHUT:
UO until the triccing of tha reactor
.]
21 coolant pumps, there in most likelihood had been scne fuel
..mersi a.corrers. inc. j 25 damage from the initial transient.
However, we're just not
4-8 jwb 18 1
sure as to the actual extent of any fuel damage at that time.
2 As you will see as I continue, the severe part of 3
the transient is yet to come.
I 4!
COMMISSIONER GILINSKY:
Let's see.
Where would i
5 this fuel damage come from at this point?
6 MR. EISENHUT:
The reactor was starved.
As the 7
pressurizer level went down, the plant did not have any makeup 8
coolant coming to the plant.
It was not being cooled because 9
there was no feedwater system operable.
There was no I
i 10 :
auxiliary feedwater system ocerable, and the high-pressure l
11 ejection system providing cucl makeup to the cold legs of t
i 12 !
the plant had been turned off.
13 l COMMISSIONER AHEARNE:
So once you went into I
l 14 l Saturation, it passed that?
l l
\\
15.
MR. EISENHUT:
That's right.
i i
16 '
MR. CASE:
In our later work, we try to sucerimoose 17,
on these times when we think the core damage began, but we 18 !
just haven't gotten en=~
=- 'n our work yet.
19 !
MR. EISENHUT:
It's pretty much speculation at this i
20 point as to actually when damage to the plant actually occurred.
- e believe, as you will see in the next few steps, chat there 21 1
o, i certainly was a continuing -- another piece of severe transient.
a,
23 !
- 1R. CASE:
In other words, there was probably =cre 1
24 than one vciding of the core.
11 241 Feceral A eOQ r'ef t, I nc. -
l 25j MR. EISENHUT:
Voiding of partial parts of the core.
i
'l
i-9 jwb 19 I
1 COMMISSIONER AHEARNE:
Your conclusion is, after 2l the aux feed came back on, or when they opened.the valves, it l
I 3'
began to --
i i
4 MR. EISENHUT-
'1 hat's right.
You certainly --
I 5l after the high-pressure injection was restarted, about 11 to i
l 6'
12 minutes, and af ter the auxiliary feedwater was restored 7j at about 8 minutes, the plant, you would expect them to be i
i aj able to bring back to some kind of a more stabilized system i
9 parameter approach.
t l
I 10 ;
COMMISSIONER AHEARNE:
Jow you say that about 11 l 1:15 they tripped both pumps in 3?
l 12 MR. EISENEUT:
Ihey tripped both pumps in loop 3.
l I
I 13 l COMMISSIONER AHEARNE:
And A was running?
I i
14 MR. EISENHUT:
At 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and 15 minutes.
I 15 MR. CASE:
It was running at that time.
16 '
COMMISSICNER AHEARNE:
doch?
d 17; MR. EISENHUT:
Soth.
All four pumps were running 4
18 up to this point in time.
They tripped, however, the two i
19 pumps on loop 3 at 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and 15 minutes.
20 And at 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and 40 minutes into the transient 21 they tripped both reactor coolant pumps also on loop A.
.I I
22 i CCMMISSIONER AHEARNE:
Do you know why?
a 23 l MR. EISENHUT:
We don't know why.
t ono 2.1 COMMISSIONER.3.HEARNZ :
Either?
4r'if%,
-E9Ctf 36 R fDCf ttf t. Inc. '
25 CEAIEMAN HENDRIE:
Was it clearly a nanual trip?
Or
4,-10 'jwb 20 l
was it --
2 MR. EISENHUT:
It was a manual trip..
It appears 3:
from the best records, that it was manually done from the 1
4 control.
5 COMMISSIONER 3RADFORD:
Shere have been some reports 6
of a violent whistling noise or something from the plant in 7
the early morning hours heard by people who live nearby.
Is a
there a vent in the course of the chronology that would have i
I 6
9' given rise to that?
l l.
i 10 MR. EISENHUT:
That wouldn't be, from the scenario ;
I i
11 I' m going through, directly as an item here, because we are I
12 {
concentrating on une crimary system.
l t
I 13 We believe, however, the atmospheric dump valves 14,
on the secondary system were probably dumpe.d to the secondary I
i l
i 15 system, not the reactor system, to dump the steamed atmospnere. -
I l
l i
I 16 ;
MR. CASE:
We haven't gone into nhat scenario yet.
l 17 We haven't J. coked at the secondary side.
18 '
MP. EISENHUT:
We've been concentrating primarily 19 on what happened to the reactor, as opposed to what happened 20 to the secondary equipment.
However, you would certainly i
21 '
expect something like atmospheric dumps.
22 q CHAIRM'd HENDRIE:
" hat would have been back in that:
l3 early first minute or two period?
g9 23 i
24 j MR. EISENFUT:
First few seconds.
Eet tr81 ReOQf fff t. Inc.
I 25 i Over the period of time between about 1-3,' 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> d
i i
i
4-ll.jwb 21 1
1 to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, we believe the core began a heat-up transient.
2 COMMISSIONER GILINSKY:
Le t me as k _yo u, Darrell.
2l When the feed pump on one side trips, does it trip on the I
i 4i other side, too?
5 MR. EISENHUT:
Hot necessarily.
6 COMMISSIONER AHEARNE :
There's almost a half an 7
hour lag between them.
8 MR. EISENHUT:
You could be providing feedwater 9lj flow to one steam generator as they are operating in the t
10 '
present mode right now, operating with one steam generator.
I 11 i COMMISSIONER KENNEDY:
What conceivable reason i
i 12 i might there hace been to cause that kind of a trio?
i 13 !
MR. EISENHUT:
Of the --
l 14 COMMISSIONER KENNEDY:
What would they read?
i t
15 MR. EISENHUT:
Of the reactor coolant pumps?
16 ;
COMMISSIONER KENNEDV-ves.
What would they read i
17; to suggest that might be a course --
18,
MR. EISENEUT:
I'm just not sure.
i i
19 CRAIRMAN HENDRIE:
System pressure in that range 20,
at about 1000 pounds?
21 MR. EISENHUT:
System pressure had been changing 1
d considerably over that period of time.
I believe it was 72 "
- i 22 L probably about in that range.
i, sr r' ? g
,{
d.h.
A ' 'A 24.'
Reactor coolant pressure --
l E ctr11 A eCorttr1, Inc.,
?
end #4 25 '
CHAIRMAN HENDRIE:
Say at 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and 10 minutes.
a I
R 3792*
22 T5.
d I
gsh i
il MR. EISENHUT: In an hour, we had about a thousand 1d il
?
2.:p s i.
So I assume right up to an hour and 15 minutes.
It was
!about 1,015.
'- 7 have l
i I will look tnrouch mv nctes here anc sea 4
i
'I i
something that long in time on the reactor coolant.
~
5 I don't seem to have it.
Excuse me.
]
7;l pressure at about an hour into the transient, it was coming Udown to about -- it was at about a thousand at an hour, or g
'between 1000 and 1100.
9~
The nearest I can tell from these rouch feeline 10
- is lthat it stayed at about -- in that range to about an hour and
,l i
a half.
i, At about an hour and a half, it underwent a severe 13 !l
- I!! reduction to about 700 osi, which was reached at about 2-1/4 14 1 n
1:. Lhours.
\\
i 1j COMMISSIONER AH.EARNE:
The ten.perature at that time 1.4 1.,.lwa s --
MR. CASE:
At 1-3/4ths to 2.
We have a hot lack
,3 i i
,_ '_temceratura of 620.
17 MR. EISENHUT: Yes.
During this heat-up transient, 0
a
,1,r ght after the point I just mentioned where the core began to 2
heat up, One hotleg temperature began to rise and rose to
-~
about 620 degrees F.
It was off scale within 15 minutes.
3 CHAIRM.I.N HINDRIE :
This was 4-F a* 0r 31 G eCC r'ar3. !"C.
1.i N ',9 -ib
,4E 4 O
23 l
1
_l '
gsh 2
[
MR. EISENHUT:
The hotleg temperature at about a
1 2 two hours.
l 4
3 CEAIRMAN HENDRIE:
Darrell, before you get away frcm i
d me on the pressure, that c.ositive suction nead rec.uirements on i
5 the se c. ume. s, it's only a few hundred counds, isn't it?
6-l MR. EIEENHUT: I believe that's right, yes, sir.
1 7'
CEAIRMAN HENDRIE:
You have to be able to come all 3'the way down into the residual neat removal, system pressure 9i! rate ficw --
10 MR. EISENHUT: I think that's ric.ht. Normaliv., thev.
i lrun 11 these pumps down until you cut down to tne RHR =cde, l
One residual heat removal system, which is 400 or less.
I' l CHAIRMAN HENDRIE:
Okay, 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> hotleg temperature?
14 MR. EISENEUT:
I may give you -- since you requested 1 ': !it there, the pressure in the reactor coolanu system rose 14' frcm that value at 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and 15 minutes of about 700, and 17 'rcse to scmething en the crder of 2100 by unree hours.
'i 1 ~2 COMMISSICNER AREARNE:
Ncw what's your description of 19 the phencmencicgy that was going cn?
'O MR. EISENEUT: It's very difficult to -- cver that f
'1 i pericd of time is when = cst of the action happens, certainly.
m To give you an idea, the hot leg temperature began to rise to about 620 degrees F.
And it was off scale within 15 minutes.
- v. mew, c.m.m i :.
system was reading And the cool lec on the reacter coolant 150 degrees F.
jj( 246
24
!(
l i
i i
i gsh 3 Ih CCMMISSIONER AHEARNE:
Both pumps are stopped at l
h
.I that time?
1 3
MR. EISENHUT:
All pumps are stopped?
4 CCMMISSIONER GILINSKY:
And what's off-scale?
5 MR. E'SENHUT:
The temperature scale on the hot 4
ileg, which is the exiting, the core, it would infer that you
~
e 7 jhad a situation where there was no ficw to the core, or 3
certainly very little flow to the core.
9 i
You_have an extremel high delta 2, meaning that 10 lat the bottcm of the core --
l 11 !l MR. CASE: Of the T.
12 MR. EISINHUT:
I'm sorry.
Yes, you had a very large delta T.
You had about 150 degrees in the bottom of the core l 'a Iwhich is going in which is the result of cold high pressure 1 ~4 injection water.
And at the top of the core that is the exit, le' you have greater than 620 degrees F.
We don't know exactly 1,/ what the temperature is.
1 a-COMMISSIONER AHEARNE:
At 700 psi, what's the
- 1. *1 saturation temperature?
dg MR. EISINHUT:
I don't have a steam table, or I'd I
'l tell you.
~~
COMMISSIONER AHEARNE:
Is it around 500, 400 degrees?
w MR. EISENHUT:
Probably on that crder.
You're certainly
-.ws, nece m e.
- wav abcVe saturaticn.
aa oea 1L A 'i f CCMMISSIONER.'JiEARNE: Yes.
25 I
l i
i I
I I
I I
sh 4 l
MR. EISENHUT:
At about time equals 2.3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br />, the I~
t 1
2b
~
felectromagnetic relief valves were isolated by the operator l
i
~
'after he had cbservec leakage from primary to secondary I
side and steam generator 3.
I i
i S
COMMISSIONER BRADFORD: When do you lose the N".Iithermoccuple readings in all this?
a 7 "l MR. EISENHUT:
We haven't traced the thermocouples I
1 3jthrough this sequence.
However, when we got to the situation of,'
i 9 pI believe, just a few hours into the transient, the thermoccuples 10.iwere all reading off scale.
11 MR. CASE:
Off case high.
12 MR. EISENHUT:
Excuse me.
Off scale high.
The 13 alecmputer prints out thermoccuple readings.
However, when it
- I 14 ;l reaches the off scale high point, it prints a question mark, 1 ':, hich is the wav it's desic.ned to crint.
It's also off scale w
16 Icw.
It's designed to print a question mark, er if a 17 ' hernccouple f ails open, it will print a question mark.
.t 13 '
CHAIM1AN HENDRIE: The valves, the relief valves 19 you just talked about securing are on the secondary icop?
'O MR. EISENEUT:
Yes.
No, I believe it was the l
'l' electromagnetic relief valve on the primary system, en the pressurizer that was cicsed at that time by the operator.
~~
We co not have gccd indication as to the extent or the timinc c#
'- a -a'"a"
..m,.,-w...,,.e.
valve cceninc and closinc uc to this
- C
'~ pcint in transient.
11 Ed8
26 i
l, i
l I.
1 i
gsh 5 l
At about three hours into the transient, the reactor i
2 j; coolant system pressure had increased to about 2150 psi, and 3 '1'again the electromagnetic relief valve reopened.
At this coint in time or about three hours -- 3-1/4 i
5 ] hours into the transient, the reccrders indicate that.n the 6'ireactor coolant drain tank there was a pressure spike of about I
7'5 pounds per square inch.
It's a very short, rapid spike.
3 CCMMISSIONER 3RANORD:
What does it tell ycu?
9 MR. EISENHUT:
We're not sure what it tells us exceot 1,
10 'it can tell you a lar~e number of thine.s.
However, there was w
t l
11 i' clearly a pressure spike in the drain tank at that point in 12 thre.
13 At T ecuals about 3.8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> --
o il 1 '4 ',
COMMISSIONER KENNEL'Y:
3.8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />?
i 15 MR. EISENHUT: Yes, it's much more convenient for 16 me usuall.v to c.ive them in decimal coint hours.
I acclec.ize 17 !:for doing it both ways.
la At about 3.8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, tne reactor coolant drain tank 19 pressure shcwed another spike, this time at about 11 psi.
At
'O
.that point in time, the reactor coolant system pressure was 1
"j.
1750 psi and the containment pressure response shcws an increase me
%=: rem about ic 3 ps quite sudcenly over that pericd of time.
COMMISSIGNER AHEARNE:
And normally you say it is what in the containment?
2
.;wan =<wm, :.
'~
MR. EISENHUT:
The container is normal _y about
i 27 I
l gsh 6
! atmospheric, or slightly negative.
l t
i i.
In fact, to keep it in leakage -- it had been up to 2 l:
I this point in time, there had been a very gradual increase from at=cspheric generally up to accut 1 si.
4 i
4 COMMISSIONER AHEARNE: And now it wen * --
i MR. EISENHUT:
Now it was a somewhat rapid increase to about 3 osi.
7 l
1 CCMMISSIONER GILINSKY:. Is the containment sealed 8]
- at this coint?
9 sir.
10 COMMISSIONER GILINSKY:
It is not.
,li i
MR. EISENHUT: Perfect timing because the very n xt g
13,; step in the scenario is that the containment, -ceak containment f
Loressure reached about 4-1/2 psi and we believe the containment 14 15 : isolated at about 4 osi.
This was at time equals 5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />.
16 COMMISSICNER 3RADFORD:
What time of day is that, g,
rouchiv?
18 i
MR. EISENHUT:
About 9:00 a.m.
Acccrdinc y
- to the l.
chronology that I'm going through, I assume time equals zero
..eJ at 4:00 a.m.
COMMISSICNER AHEARNE:
So they actually declared the
... emergency somehwere in fact abcuc three hours on ycur schedule.
L' c e.<.v 1
.2 -
C". e = R i.='i"6 4 = ' '.! -
30'.
'J '
" y*
-w
.sOa
/-
.a 4.
.se n ;:eocn,, i c.
MR. EISENHUT:
Yes, sir.
They at that point in time
28 i
l h
h I
t i
1-gsh 7
- observed some racicactivity in tne drain line and.in fact, i ~
t
,a 2 "!
l
!because they had seen --
CCMMISSIONER AHEARNE:
That's where they closed off 4
B?
i End T.
5' MR. EISENHUT: I believe so, yes, sir.
6i When they saw the increase in activity, and I should 7 3qsay they also un. to that point had felt that there was an I
8 Isincrease -- there had been a leakage in tne steam gencrator.
9 So if vou see the crimarv. coolant activity ccming up, 10.ycu'd want to close the path in the steam generator, which is 11 dclosing off the locp to the outside, isolating containment in 12 th~at aspect.
13 l Between about 5 and 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> into the transient, the
,i a
4
~
reactor coolant pressure increasec from about1250 pounds per 1 ~5 square inch to 21.C0 psi.
la' CFAIRMAN HENDRIE:
Frcm what?
17 MR. EISENHUT-From 5 to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
13 C'tAIRMAN HENDRIE: On the icw pressure?
17 MR. EISENHUT:
1250 to 2100, 20 a
You will recail scmewhat earlier they opened the i
il relief valve and apparently the system was blowing down.
As it w" blew dcwn the containment pressure was coming up.
At about 7-1/2 hcurs into the transient --
. : x,,, a,w..,, I,.
COMMISSIONER AHEAR'!E:
You're still saying tha:
. n.-,
enormous delta T across the hot anc cold. legs?
1,i Ac D1
ji g
29 i
I i
gsh 8 Ii MRc EISENHUT:
Yes, it was a very large delta T.
I n.:
2 CCMMITSIONER KENNEDY:
Off scale.
,l.
.~,
MR. EISENRUT:
Yes, sir.
i COMMISSICNER KENNEDY:
Don't know how much?
l C*l i
MR. EISENHUT:
That's right.
At about 7-1/2 hours,
,l 0'the operator operned the relief valve again to depressurice 7 1,the reactor ecolant svstem to atteme.t to initiate the RER to
.1 3
try to drop the entire system pressure to 400 psi.
We have that 9 ll as a positive action that was taken.
Therefore, we certainly 10 !: knew the valve must have closed scmewhere in the interin.
11 There was a whole cycle of the valve being opened l
- and closed as the operators were attempting to respond to the 13 1rsequence.
- 1 74 ll At 7-1/2 hours, however, they made the attempt to i
15,t r v. to bicw the system down so they could get on the residual 16 heat removal system.
l
Over the pericd of 8 to 9 hours1.041667e-4 days <br />0.0025 hours <br />1.488095e-5 weeks <br />3.4245e-6 months <br />, they actually 1 ~3 ' achieved pressures decreasine. to abcut
'O esi.
Ac. c. arentiv,
10~ during this pericd of time, the core flooding tanks also partially
' discharged into the core.
- )
21 :
CCMMISSICNER KENNEDY:
To about 500, did you say?
~~
MR. EISENHUT:
They got down to about'500 psi, yes,
,.=
s _i..
COMMISSICNER AHEARNE:
The hot lec
. -,,. - co r m i
- temoerature ccme back to scalC' o
30 j
/j h
i i
a sh 9 I !i MR. EISENHUT:
At that p-int in time, I don't believe.
.i
", s o.
We were reading basically the termpatures.
We were also I
lreadingthecutlet.
The thermal couples were also not en scale
~
a i
4 a 's t.".= '
o.'.. *.i.n ~- 4me.
y 5
q At about 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> into the transient 1,
4 CCMMISSICNER 3RADFCRD: Carrell, the thermal couples i
7linto the c^re now are just putting out a series of question i
1 3 >: m a r k s ?
l 9'
a, at the MR. EISENHUT: Not at this Ocint of time but I
10 '::oint of time in the sequence we're discussing,
- v. e s, sir.
i.
11 I CCMMISSICNER BRADFORD: That's what I mean.
MR. EISENHUT:
Yes, sir.
They were, in fact, 17-,c.rinting questian marks well into Wednescav. night, as I recall.
4
- 6 l 'a i Hard to xeeo track exactiv. at tne time.
But we were workinc.
,e
'~
the c.uestion mark c.uestion late into Wednesday nimht.
a CCMMISSICNER 3RADFORD:
What assumo.tions were beinc.
made about many of that series of question marks?
is MR. EISENHUT:
Scmetime ct. Nednesday we had been
..n-
... c^an~- c v..i
.". 'a"c c.k u-
- i.d.' - ^-.x,
"a.".". " ' c
.4..
.# a c. d o s.',.. a. d.
a..A put in the thermal couples and designed the computer system as y '. 3 *.
4*
m.w.4
- s n,..
m k.o y C7e%.m*7.,
. b. s =.
.k. s d
=o v.l d. i -
t.e a..r.y
- g p
e wa
.g
- y
-ww.
f
~..W.o w o g
- s..k..w o o
.,,, -., e b, a
- s. e.
-. s c =. 4 m. m. a.. 3.*.g a T.
=..W. o.. h. o.em...p.'
y
. a a
a c. ; a jw
-- d m.e:
a C '.l a b...i".".,
o #. #.
o r,,e.7 a g a v ' ' v'
""y...
- " G." '...'.'
-om
..1,
~~
3 A
ov-y w
y m..
r~ m
,'. e coucle.
,1 >
,,, % x,.. 3
}Q gu 6.%*3 m c.d e.r.
.d.e
~. 4.m.. a,
.s q.'.4 e. n,
-.'.1 a
2~
T i
au ygwp
- n 2
.y
-a
- w
- y
31 khk I
I gsh 10 recall, certainly the question marks were readings high.
There-l 2l was certainly scme train of thought that felt that if you n
I I
8 9
i have a verv. hic.h tem =erature, the thermal ccuples may have i
I 4
actually failed open.
i I,
5 At the site --
6 CCMMISSIONER 3RADFORD :
But since they cnly read up to 750 decrees, the fact that they were all off the scals i
3'really didn't tell you all that it might have.
9 MR. EISENHUT:
They're generally designed to read I
10 isuo to about 700, 750 degrees.
J 11 '
MR. CASE:
They're not installed for diagnostic 12 cureoses.
Thev' re ' installed for research purpose s.
n 13 :i MR. EISENHUT:
For ficw distribution, core operation, i
I 14 hiand everything else.
15 '
Yes, I certainly don't want to leave the impression 16 that that was scmething in the sequence we censidered a I7 failure.
It was dust a plus that theY were there to hele us a
'3 cut.
10 At about 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> into the transient, there was a
'O spike in the containment pressure and the spike was about 25
'l counds, 23 esi.
- 11.,, r-,+M c C..m..m o-a C tr.o.
.u.. r. m v.
.1 1 - e c,,..
r<aa a
.-a MR. EISENHUT:
The bes: information we have On this
~~
tric charts
,. ;,.,, e w..., ; c.
shows verv sncrt seike un and dcwn.
It certainly is not -- we don't kncw that it was a millisecenc pulse. We don't
32 g
I i
gsa 11 I;
know it was a seconcs pulse.
It could have been anything a
2 o frem a -- v. ou can postulate a nummer or things and certainiv.,
y 1, postulating is hcw you get there.
You postulate hydrogen l
burning, for example, over some seconds.
You can costulate i
5iIa number of things.
'l 4
l CCMMISSICNER KENNEDY: As contrasted with hydrogen 7Ilexp.osion.
l 1
2 l MR. EISENHUT: You could postulate i hydrogen 9 iexplosion, I beliave.
The instruments probably just wouldn't I
i 10 !folicw it maybe as fast.
,)
I CCMMISSIC"ER AHEARNE:
But they woulc follow it?
17 MR. EISENHUT: It's verv. difficult to sav..
They m a v.
I 11 if it's a very quick milliseconcs, likely not.
la 1 MR. CASE:
But in any event, nere the containment 1 ~~ sc.rav.s did initiate.
16 MR. EISENHUT:
Yes, there was an actual pressure in the centainment, we believe, because the containment sprays n
did initiate at this tir.e.
They stoppec aftar about 5000 y
gallons of NACH was in]ected, about two minutes of operation.
'0 7
Tne scdium hydroxide tank is not quite half empty.
,3 CCMMISSICNER GILINSKY:
Now what triggers this spray?
MR. EISENHUT:
Pressure in the containment.
C "w.'d'4I o' ' C.'Ir..*4.' "?.a' RN" -
"+av
. ". = - - -' 4.S. a.
a s o e.". - '.'.' ' ".
sn.
2-
'1 AA
- ' t :-
triccerec --
1.
Aod
.. c e,3 = < ec,,m
- S a t e nj = a b h. T.p v.'
4 -a ae
- r s*% T
+w 46--==
A s
.*.L b y.
3.,. a s s,6 4 4,,. a.
a.e W o a +. S a
girl 12 '
33 l
11 h
MR. EISENHUT:
Pressure, I believe.
i u
2 l
]
MR. CASE:
Yes.
3 i
MR. EISENHUT:
At about time equals 13-1/2 hours i
i l
into the transient.
That is at 1750 hours0.0203 days <br />0.486 hours <br />0.00289 weeks <br />6.65875e-4 months <br />, or 1730 hours0.02 days <br />0.481 hours <br />0.00286 weeks <br />6.58265e-4 months <br />.
c 1*j CHAIRMAN HENDRII: Just stick with the time frcm sero.
t, (Laughter.)
7 -
MR. EISENHUT:
Let's see, atout this time into the 3 : transient 1,
- 'i CHAIRMAN HENDRIE:
You're going to convert into i
10 ilreal time?
11 1 MR. EISENHUT:
We ccnverted to the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> system 12 because that way we avoided a lot of confusion of those of 13 ia, us following the accicent.
l
It was about 13-1/2 neurs into the event.
ic
'~
CHAIRMAN HENDRIE:
Which would be then --
l ~'
MR. EISENHUT:
That's why I converted to 1750.
Then I was going to convert to that's about 5:30 in the 1 ~:
afterncon.
3 Y CIMMISSIONER AHEARNE:
1750 is 5:50 in the afterncen.
'O MR. EISENHLT:
Yes, yes, correction.
71 At that point in trme, the electromagnetic relief
~
"a'vas we = w.icsed
.4...=.. = - =- - e.- ~^ -=:-asa~u d.'e
..".a-z v. = =-...
to collapse the voids, to collapse any bubble that michc be 0s A
4
.A.s.
..,o. o.
. E *C trit 20 00 r '?'1
C.
'~
An attempt was made to try to start the reactor coolant
gsh 11 34 i
1 I
1 pump, and in fact, it started.
j CCMMISSIONER AHEARNE:
You say to collapse any i
7 i i
~
' bubble that might be there?
.1 1
i 4
i MR. EISENHUT:
At that point the thought was to c
j
~ i.try to repressurize the system.
There was speculation anyway i
4 'that there was voids or perhaps bubbles in the system.
~
l 7'
COMMISS!CNER AHEARdE:
Subbles --
i ra' MR. EISENHUT:
Bubbles.
At that time, we weren't l
9ilto the point of analyzing exactly what it might be.
i 10 i j
CHAIRMAN HENDRIE: Of steam, I think.
11 i MR. EISENHUT:
It coulf have been steam.
l
CHAIRMAN HENDRIE:
It would have been the, obvious l'"
!thought in mind.
1 **
MR. EISENHUT:
We had very little indicatio.
1 ~:,ccurse of the things we learned over the last few days.
u' '
COMMISSIONER AHEARNE:
Had you reached the conclusion
).
tnat natural circulation nad or had not been occurrinc, at 1 ~: that time?
19 MR. EISENHUT: I don'c believe we had reachec a n
conclusion.
Howe"er, if one looks at tha temperature at the
,1
- outlet of the core and the temperature at the inlet of the core, you could conclude that there was very little natural S' circulation.
In fact, there was very little circulation at
all with the 600 plus, /00 plus degree temperature on the outlet m.,
- < wm e.
Ind 6
' and 150 at che inlet.
11 2i72
35 R 3792
.r r - wa rR
-7&8 l
l
% 3 1i cob 2:ISSIO!!ER AHEARI!E:
So the 13-1/2 hour, your l
2 readings were still off scale, high hot leg?
i, 3
MR. EISEllHUT :
We would have to che ck.
I ' m j us t i
4' not su::e what the readings were at that point.
i i
1 5
At that eoint, one reactor coolant.cu o.,
nume. 1A, 6 !
that is, the A pump in the 1 loop on the A steam generator,
7l was restarted.
i 4
a1 From about time equals 13-1/2 to 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br />, the i
9 reactor coolant system pressure gradually increased from the i
10 650 psi it was at to about de 2200 to 2300 psi range.
I 11 '
CIIAIRf*A: HE !DRII :
When did it get back to 2200?
12 l MR. CISE::UCT:
Some time during the tine frame of I
13 !
13-1/2 to 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> into the transient.
I don ' t have detailed I
14 '
information that goes into that many hours in de transient, i
1 15 '
as to the actual traces of the pressure trip temperature.
It's 16 unclear whether the actual pump in loop A was started at h,
17 :
13-1/2 hours or whether it was s tarted during that period of i
13 :
time or towards the end of that period of time.
d 19 :l But it was restarted during the period of tine such 1
I 20 l that at 1600 hours0.0185 days <br />0.444 hours <br />0.00265 weeks <br />6.088e-4 months <br /> the hot leg temperature had decreased to i
21 about 560 degrees F.
,, o C u..a.r.e.u3... a _r. m..o._-
v_
t,.
.,_ a..
_3 ;:_, o L,, s,
r I
2.,
i 2._r - :.. n u. :
At
.o hours, yes, sir.
- m
..R.
y l
24 CHAI. "Id! III:IDRII:
When ve get to nidnight, we're
.merv a,cornes.inc.
25 going to convert, okay?
11,5jS l
36 e.2 I
I i
i i
i 1
MR. EISE!IHUT:
I'm not sure.
I f
2l CIIAI?J927 HE:!DRIE:
All right.
Onw ard.
I i
3, CCMMISSIONER AHEAPlE :
Hot lec terc.erature had i
i I
4' decreased to?
l t
1 i
1 5'
MR. EISEUHUT:
Hot leg temperature had decreased to t
l 6'
560 degrees F.,
and the cold leg increased to 400.
i 7'
It was at that point that we felt there was circu-l l
t 8 !
lation through the steam generator, through the core.
i i
9!,
COM2ilSSIOtER AHEA? LIE:
Gettinc steaminc?
10 I MR. EISE:' HUT :
Getting s teaming out of the secondary t
l I
11,
side of steam generator A.
There was. steaning to the condensor.
i 12 '
From that point on, there was an awful lo t of things I
13 I happened with ecuipment either being turned off, stopped and 14 started, as people were manipulating the secuence from that i
i i
15
.coint o n.
16,
I think it's not important to continue necessarily 1
17 ;
from that.. point on until today, as an aw f ully large numb e r o f 18 things happened and went up and dcwn, restly no t havine. any i
i 191 significant effect on the situation.
1 20 COM:!!SSIONER AHEAPlE :
2 cur conclusion would be th at 21 any axtensive core damage probably occurred prior to this 3
i 22.l point in time?
i
'l i
23';
24 2. EISE': HUT :
Yes, sir, we.' re culte sure o f that.
21 Frcm that point in time it has been s teaming cn s tea.m generator 2.ru %rms. me.
25l A to the condenser.
The condenser ncuum was re-established.
44 erg d' O d
A.%
3, JJ nte I '
i f
1, The reactor coolant systen has been gradually cooled down over I
4 I
2l the next day or so to its present configuration of about i
i 3-280 degrees F.
a t bo th the inlet and the outl t, with about i
I 4l 1,000 psi en the sys tem.
i l
i i
5' As of this time -- new I'll skip from 1600 hours0.0185 days <br />0.444 hours <br />0.00265 weeks <br />6.088e-4 months <br /> 1
6, to days.
As of Ac.ril th e 4 th, t o d a v., they are still in this I
7l situation.
There is high radiation in the containment.
We l
8!
es timate that there has been some core damage.
All fuel I
l 9'
in-core thermoccuples at the outlet of the fuel regions are 10 reading below 475 decrees F.
They are using she vent valve, i
1 Il l which is the snall valve.
12 !
COMMISSIONER KENNEDY:
There fore, below saturation?
l 13 MR. EISENHUT:
Therefore belcw saturation, yes, sir.
I.
14 i They 're using the small vent valve in a one-inch i.
15 l line which is partially open to partially blow down on the 16 ;
stern generator, and.thev ' re su.e.elv. ing take-up ficw at essen-
- l i
il 17 1 tially a ccnstant rate, holding the reactor in that configura-13 tion.
19 '
't is very sicwly cooling down.
And the reac tor a,
s tructhre 'hs a slightly negative pressure.
It 20 contal.. ment
~
~
c i
21 ' has had that fo r the lasr couc. le of dav. s.
.i 22 a That basically covers where we are up ce this coin t i
23 i 4-c And going back through the scenario -- if I could 24 have the second slide, please.
11 ggo
.~,..,=.x,..,a~..
25 '
(Slide.)
38 i
e4 l
1 I
1 I have cone throuch and hichlichted the major areas t
I 2i of things that apparently went wrong to rake this transient i
i 3
more than an anticipated transient, that is, a design basis I
4 transient, and things that actear to have comolicated the i
S' situa tio n.
6 The first one, of course, is that the redundant l
7i emergency feedwater system was isolated from the test and I
3 naintenance operations, and it was lef t in that configuration.
I 9
This is a violation of the plant technical specifications.
10 COMMISSIONER GILINSKY:
C an I ask you again -- I 11 didn't understand your answer earlier -- how long do we es ti-i 12,
mate that they were isolated?
I 13 MR. EISE7 HUT:
The auxiliarv feedwater?
l 14 '
COMMISSIONER GILIUSKY:
Yes.
i i
15,
MR. EISENHUT:
The auxiliarv feedwater 16 MR. CASE:
Sefore the transient s tar ted.
i 17 COMMISSIONER GILINSKY:
Prior to this accident.
13 '
Maybe I;E % nows.
Up to about two 19, weeks.
20 MR. JCRDAH:
And that's the maintenance --
21 CC!!!ISSICUER GILINSKY:
So all three of then were 1
22 isolated for two weeks?
O
.I 23 j MR. JOEDAN:
That's our understanding at Sn_s time.
I 24 "
MR. EISENHUT:
f4e dink so.
We are tieing it, we
-Fe*tf 3l Rtoortt91, IRC.
I 25, think, to a test and maintenance operation which was conducted oc3 f
b i
39 t
t e
D.
l 8
l l
9 l
1l abcut two weeks prior to this event.
I i
i 2i CO DiISSIONER KE:i!!EDY:
All of those valves were i
l 3
tagged as closed?
i i
4 24.R. JORDAM:
Yes, that's the indication we have from I
5 interviews with operators.
I 1
CCM ".ISSIOUER KEUNEDY :
All three of den?
6]
i 7;
MR. JORDAN:
There were t.vo valves for the three 3,
o t:nc. s.
l 1
MR. EISEM* C'":
It's actually a three train feeding d
9 i
into two train system.
There are two -- I usually say it 10.l 11 wrong -- two electric-driven purps and one steam-driven pump, 12,
to give vou redundancv and diversitv..
'"h e y go _ throuc.h I
i i
13 redundant valves in two lines.
And those two valves were i.
I 14 closed.
15 COMMISSIONER AHEAD,HE:
And so, to make sure we check 16 ]
the understanding, the tag that shows on these valves in the i
17 ] control reca is the tag that indicates they were closed.
Is 1
18 it a tag ' Edit fndicates they ' re undergoing maintenance or a 19 '
tag that indicates 20 l MR. JOP. DAN:
All we have at dis time are statements i
1 21 1 from the cperators and th e f act dat there was a tag on the
,, t
..,3.,,
~,,..,,,a.-
.". e c.o n.. o.1 - r s..
- .' e d, o '. ' * ...~. n-
."..=. ' a-
+
.w s
n
.v.
ww.6w.v
.w w
qq l C.3
- *.3. a 2g.
w.C.n.f a,
'e..Cy
.q.h. 2.
t -
C.
?
A s
.k. o, sg.
aj c G~. e =,.. g 3 n, s 'r.e.
- r*.*s.+s g v..
e-
..n s
A e.. s..
'.m... w n..o.h.a.
4
....w 4
.s vv n w
n
-E *Cef 31 R eCC ritri, I nc, 25 says "'lalve is Closed" or whether it s ays "The systSO is in 11 ZG?,
a6 I
I I
l I
1 L aintenance"?
l t
2j MR. JORDA2T:
No, we do not.
l I
3 I COMMIE SIONER KENNEDY :
It might not necessarily mean !
i 4
the s ame thing.
i l
I 5i MR. JO RDAN :
That's correct.
i l
I 6
6 MR. EISENHUT:
Continuing with the listing of Shings l 71 that had gone wrong through this scenario, it appears that 1
1 3,
the electromagnetic relief valve f ailed open, that is, stuck i
9' open.
It's very difficult to say precisely --
10,
col'J.ISSIONER AHEARNE :
S tuck oc. en or f ailed to c.oen?
I 11 i MR. EISENHUT:
Failed apen.
That is, stuck open.
i 12 ;
It opened and continued to blow down, and apparently did not i
13 l reseat at the time it should have.
I I
14 !
COMMISSIONER.EEARNE:
Could that nave ceen manuallv. l i
L i
15 -
.ined open or is it automatically?
i 16 ;
MR. EISENHUT:
I believe it should have automatically
- I I
17 resea ted, reclosed.
13 t COMMISSIONER KZNNEDY:
It could have been manually i
i 19 held open?
20 MR. EISENHUT:
In theory, yes.
In practical, I i
21( believe not.
il 22 j The third thing on the listing is th at the pressurizer
't 23 l level indicators appear to have given erronecus readings.
I 24 l MR. CASE:
Of the actual level in the sys te..
-m er st A eoo r*ers. I nc.
25 '
MR. F.IS ENHUT :
Of th e actual real colla sed ancunt se
.~ m
.1.. o (j-t
41 e*/
i 1
of water in the pressurizer.
We say this only because the 2
pressuri:er level indicator trace on the strip chart recorder i
i 3;
in the centrol room shows an extremely rapid refilling of the i
i 1
4 pressurizer.
t 5:
COMMISSIONER AHEARTE:
So the centrol rcen trace --
l 6 i MR. ETSETHUT:
The operator may have had -- may have i
7 looked at the strip chart and c.ot the actual readina., and used j
l 8
the actual reading in his j udgme nts.
But the information being 9,
given by the instrument may have been erroneous.
We're not i
I 10 certain as to what this -- what led to this situation.
- However, t
11 :
you'll see on our actions that we are going to be taking very t
i 7
12 l shortly, this is a consideration.
t i
13 !
The fourth item on the list 14 p COMMISSIONER AHEARNE :
Tet te just one last question i
15 the re.
16 You aren't saying that it was a nisinterpretation of 11 l
17 the instrurent here.
You're sayine the cperator prob ably read 18 the instrunent correctly, but the ins trument itself may have i
19 ceen civinc =-. correct reacing?
20,
MR. EISENHUT:
Yes, sir.
If the operator read this 21 instrurent, we believe it will probably give -- it's giving
.i 1
22l you an erronecus reading.
l MR. CASE:
On the other hand, this is not to s ay 7,
1 24 tha t the operator should have exclusively read this instrument
. dCarat R ecor'f rt, I t*C.
i d
'S,'
ur.i.~. ~;
=.".s ' a.". ~-.
.s
.L (s (,t l
42 i
e S.
I 1i MR. EISEMHU"' :
That's a good point.
i l
i f
I 2{
The fourth iten on the chart says dat the contain-i 3i cent did not isolate on ECCS actuation.
It appears that th ere i
i nav have been a deficiency in the containrent isolation l
4r i
l 5;
function, in that it appears that it did not actuate and it l
i 6:
will not isolate containment i=nediately upon ECCS actuation.
7!
It appears that it recuires a 4 psi in the containment.
i i
8 CC?iM'SSIONER AHEAFllE :
Ynat. are the specs ?
i 9
MR. EISENHUT-
~ "elieve we are now presently check-i I
10 '
in7 into that.
It appears that the information we have -- and f
i 11 i we've just -- when we were actually on our way over here --
i 12 ! was that d at was the way the plant was intended to be designed, i
13 4 psi.
i l
14 '
COMMISSIONER AHEARNE:
So when you say that th at i
15 was -- when you say that went wrong, it 's no t senething dat 16 went wrong.
It oper'.ted as it wasi nerhae.s, desicned to.
But Il i
17 i you' re saying the design may not have been correct.
I 18 !
MR. EISENEUT:
Clearly.
i BU 19 :
Things that went wrong include bo d things that were 20 maybe erroneously designed in the design error, Sings tha 21,, were c. erhacs e. ersonnel at de site made a mistake, or thine.s 22 ' dat Calf u'.ctioned, et cetera.
It's a cortination of all of I
- i
,,. ' do s e - thin c_ s.
.. j
,, 1
~
.-..---a
.=
=
u,.y,.. = = a z ~., = R c,...,w,,, :
, ut :: Oe c.3 ear, desi=n a.
3 z
-*: <si Recer ers. inc.,
25, error, if it had been approved at 4 psi, technical spec --
l 0
11 R.l.i
43 e 9-I I
I MR. EISENHUT:
It's not so much that the problem is 2l the 4 esi as much as --
I i
3!
COMMISSIONER AHEARNE:
As the ECCS situation.
I i
as cerhaos when vou have a i
i i
Sl blowing down situation to the point where ICCS is trioced on, 6
due to 1600 psi in the vessel, it may also be appropriate that 7
the containment should have closed, and that is sateching i
3 we're clearly locking into.
9' CCMMISFIONER AHEARNE:
But is that a requirement 10 that is laid on the design?
I 11 MR. EISENHUT:
That we had laid on in the past?
I 1
1 12 l do not believe so.
t 13 !
COMMISSIONER AHEARNE:
Okav.
l.
I I4 l CHAIRMAN HENDRIE:
I don't recall that as a require-i 15 l rent, John.
In fact, it seems to me I recall scne arguments 16 '
ibout whether in f act it should be hooked so vou c.et a contain-g o
17 ment isolation when you get ECCS actuation, or whether it i
i 18 ll should be inde endentiv tricced bv tonitors on containnent
'l;l I9 '
co nditio ns.
,0,
I guess it would not be unf air to po int out tha t 4
i 1
'la containment isolation would also have occurred on the ranual
- ' n, sicna_ at a n v. c.oint.
Aa.
. m... =_ g r.. n g ~..
- m..u. _, _ _i s um- - - a_ c -.
i
^4 In any went, the containrent var not isclared.
. cerv mewners. inc.
-c
- -"4 _ ac,a... "o
..k. a._
C ^.' "._r S ~_ ^ ". 7..
^ 7.?s r. e c.o.' -
C _' _-
o_.' _'
u v
s.
, n l
.b A, D O
44 e 10 i
I l
i i
i other B&W plants, two questions:
First of all,. if you went 1I l
2ll throuch that secuence of events in the other S&W olants, would it oroduce the same results that we have here?
And second, r
3 what is it about the reasures you've taken since then that 4
i assures you that you won't go through that sequence of events?
I MR. EISENHUT:
I'd like to hold that just for a
=ctent, if I could.
We'll get to j us t th at, because we're walking through the mirror image of this in a =cment, as to g
what actions we've taken --
9
.7 a
actions we plan, 10 MR. EISENEUT:
We plan on taking to make sure thos e jj situations will not cccur.
12 :
i c
e st one, r.ow?
13 Are those plants all designed close enough to this t: tat the i
14,
sa.e eg nn ngs would produce che s a.me ends?
1 15 MR. EISFNHUT:
Certainly they are in the case th at g
If you closed off all auxiliary feedwater you will have a 37 tr ansient, fes, sir, a very severe transient, which then, if jg vou concound it bv 19
- a f ew nore situations, vou will certainly i
get to the same point.
.to,
t i
,l ]
The actual systen design is slightly dif ferent, in
.I.l the sense that here you do have a certain arrangenent cf punps 2.,
2
,3j and valves which in other pumps are slightly dif ferent.
2 t
..owever, u.ne enc crocuct.
- i..
is t,n e s ane.
_ :_ vou close c:_:_ u.ne n
-r ? Carat R eOOf *tf t. I RC.
two different trains, cr whatever nurber of trains of auxiliary
- 3 s4 ccm
.A..t Abd
45
.a 11 l
,f feedwater you'have, yes, you are going into the same situation,i l
i i
which I should coint out is a design basis transient.
That is 'i 3
analyzed.
It's a loss of all feedwater.
l 3'
COF21ISSICUER 3RADE'ORD:
What about PWRs?
Same 4;
i i
answer?
5 ll MR. EISENHUT:
I would think so, yes.
Certainly the sys tem resconse on the o ther ec.ui= cent that 's involved
/
l would certainly respond a lot differantly, and 'cefore you could 3
j really know the ef fect, vou would have to do a full-blown 9.
l detailed sys tems analysis.
We 'll come back to j us t exactly 10 I
l Eb.at coint.
11 '
The last item on it is that it appears -- and this i
i is the item we were talking about earlier -- it ancears 13 :
f at least twice that perhaps the core was partially uncovered.
14,
i 15,
The second time was because 'the reactor coolant pumps were trinced.
16 '
ti CO.504ISSIONER AHEARNE :
iou skipped over the ICCS i
i 18 l beinc turned o f f prematurely.
i COCi SSIONCP KINE DY:
Could vou refresh nv emerv?
19 i At what point, what time, was the ICCS turned o f f ?
As I
,0 >
4 i
l l recall, it came on at two minutes.
Hich.orecsure in d ec tic n s
l-
,, ! was initiated at two minutes into the trans ient.
1
.m....
e
.c ;.... g.
- c..
.v
-2 m
.e
.. 4... a_ s.
Ona-
'..4^
~=e="-=
4J
,, ' injection pump was manually tripped off at 4 ninutes and 20 s
- tral G eOCf ?tf t. l *C.
s eco nds, and the c:her pump was tripped of f at 10 niautes and D $'
1.h A /v i
46 i
e 12 I
i i
1 30 seconds.
l 2
Remind me again.
When were i
3 !
the reactor coolant pumps tripped?
I l
4l
. iR. EISENHUT:
The. cure.s in-loco B were trinced off I
5l at one hour 15 minutes, and loop A one hour and 40 minutes.
i 6 !
It was at that point, one hour and 40 ninutes, that I'n refer-i 7;
ring to on the last item, or de ccchination of tripping of I,
I 8't cume. s in icop A and loop 3.
I I
i 9
COM2iISSIONER BRADFORD:
Earrell, when you say that 10 the cutoff of feedwater is a design basis accident, what is i
11 i it that is succosed, then, to save it fron the rer t of the i
i 12 1 sequence?
I I
I 13 -
" ".. EISENHUT:
Well, there's a combination of the l
1 14 l emercencv cccling systers.
Ycu would put on some indection 15 l flow and vcu wculd oscillate with oper.ings to de valve and il 16 ll f alling down, and you would continue to run de systen.
f a
a 17 l I should point out, dough, th a t--
18 '
CCffiISSIONER SPADFORD:
Where is dat you get away, 19 th e n, from de design basis accident?
20 i MR. EISENHUT:
I should point out the auxiltary I
l 21 L feedwater system is really, on rest plants, actually an emer-
.I l
22 ; gency system.
It is a s af e ty-grade sys ten.
So we really i
22 ' don't costulate, usuallv, de comple te wiping cur of de sys ter,
i 24 It's a less or f=ectater ficw, is
-l o transient da: is ana-
. vr* eral leOCr'ers, Inc. (
25, lyzed.
<w y y.L (D
i 1
8 4/
e 13 1
1 1
It would be at this po int, depending on the unicue l
2 ascects of the design -- if you have nultiole diverse emergencv p
i i
3' feedwater, we wouldn ' t pos tulate the complete losing of all t
4 feedwater.
You would have to have some nore failures after I
l 1
5.i tha t, Ehouc.h, before you ' d get past into the design envelope i
6' or out of tne cesi n envelope, wnicnever side you're locking l
3 7
at.
al COMMISSIONER BRADFORD.
Yes.
Out of, I think.
I i
9 MR. EISENEUT:
These are basically tne six items i
10 '
that we believe have gone wrong in the sense tha t these are i
11 }
things that happened that were major contributors to the l
l 12 i event.
Perhaps I should have labeled them that way.
I don't 13 want this to mean any one particular person was involved or i
i 14 '
any one particular group was a cause or design cause, 15 et cetera.
16 COMMISSICNER AHEA?l!E :
Now, scme of those are l
17,
positive statements and some are probler.na tical, i
l i
18 '
MR. EISENHUT:
Yes, sir, and that is because of the i
i 19 situation where we are today, where we are taking the info rma-
.1 l
20 tio n as f as t as we can and continuing to analfre it.
- 2cwever, 21 at the same time, our primary mission has been to ensure that 22 h Three Mile Island is safely cooled dcwn.
And that 's partially
.i l
22, the reascn why we have no completely analyzed every aspect of a
t 22 the prcblem.
% oc tr 31 R eOO r!ers. I f'C.
25 We have analyzed the problem, hcwever, we believe, 11 270
i 48 nte 14 l
l 1I to the point where we can identify those principal contributors j I
I I
2; to the accident as we unders tand them today.
These are cer-I 3
tainly those, or some of tho s e, and detailed evaluations will i
i l
i 4-be carried forth to ensure to what decree these were the i
i i,
i 5
con trib uto rs.
6 We really can't answer the question of what if you 71 had only three of these and not the o ther three, and all t
8 dif ferent combinations.
That takes time, t
i 9,
COMMISSIONER AHEARNE :
I guess I'd say you had two 10 prinary objectives:
One on TMI and the other is as rapidly i
11 ;
as possible to identify to the o ther operators --
1 12,
MR. EISENHUT:
Yes, sir.
That's why I said, we've cone i
t 13 t throu9h to the coint where I think se have identified the i
I 14,.
principal contributors.
i i
1 15 MR. CASE:
And of course, before we had taken this i
16 step we had already issued dhe bulletin -- if you' re through, 1,
17 Shen Ed can talk about tha t.
18 l COMMISSICNER 3RIDFORD:
Well, let ne come back to 1
19 the question I asked before about notification tine.
I can 20 understand your point being that everv. body is verv b us 'r and 21 you don ' t want to pick up the telephone and get busy signals 3
22 q and stand there tapping the walls.
But I guess I'm also a 23 l little surprised to find that there isn ' t there 7.ust be, l
24 '
for example, sone instan: way of notifying the rest of the
, e erai Aeoorters. Inc.
d disO. atch s'./s ten Or whatever the relevant.JCwer Cool is that l
1 1
OY s
A- #.L l
49 2
l cte 10 i
11 v.ou're goinc. to have a erobler.
2' MR. EISENEUT:
Yes.
Don't let me leave the impres-I 3'
sion that everyone went to wo rk on this probler and didn' t i,
4 continue to do those kinds of things.
There was a considerable:
i i
I 5;
amo un t o f wo rk unde r way.
There's a considerable, large 6
amount of the s taf f that has been turned of f of everv. thinc.
I 7j else, just so all the relevant aspects of the problen can be l
3 worked and ac.cro.criate no tifications.
L 9
CO!OiISSICNER 3?2-QFORD :
I ne ant notific atio ns 10 ;
COf0!ISSIONER AEEARNE:
In the firs t three hours.
I i
Il !
f1R. CASE:
We j ust haven' t locked into that part of 12 '
it.
I don't knew, reallv.w how we can answer your cuestion.
13 l COFli!SSIONER 3RADFORD:
Let me tell you what 's l
14 '
troubling me.
guess I had had the conception that wnen I
15 things started to go seriously wrong in any of these plants.--
16 this wouldn't need to be B&W -- that we would know about it a t
17 :
little scener, whether it would be j ust some button that 13 !
screbcdy would push that would ring in Region 1 headcuarters 19 that just told you there was a probler and Shat the NRC cught i
20 to be cranking up its response.
21 Had the event been an even more sericus one, lil 22 ] cbviously, having four or however.rany ". curs i vas go by would 23 be -- night have been very serious.
And one of the things that I
~<
I would like to focus on right away is how we can be s ure cha:
- 4 eral Reoorters. Inc,
- 4"' we would knew sconer at any plant, at any time, if something
'11 A ( o.s A
r~ m' 3
went this far alone.
CR 3792 50 mi: jwb -
49 1
MR. CASE:
I'm not suggesting that's not a good i
2l idea, Mr. Commissioner.
We're just not prepared to deal with i
3i it today from what we've done so far here.
t 4'
COMMISSIONER GILINSKY:
Wasn't there scmething on i
i t
i 5l yor-bulletin on that?
i i
t 6'
MR. EISENHUT:
- Yes, i
6 7i MR. JORDAN:
I'll start with the end of the bulletin h i
i 8,
then.
\\
9 The item in the bulletin was "to review your I
i i
10 '
prompt reporting procedures for the NRC notification to 11 j assure very early notification of serious events. "
l 1
12 That is subjective, but it's alerting the licensees h
13 l that perhaps we didn't get adequate notification in this f
i i
14 '
particular event, and we will provide additional instructions i'
15 to them as soon as we understand what their notification 16 ;
scheme was and when the earliest point we feel we should have 17 ]
been notified.
18 So we have merely pu~ out an alert at this point.
19 COMMISSIONER 3RADFORD:
I would think there would 20 he some way that we could describe with reasonable precision 21, the point in time at which we would want to be notified, and
. I, 22, just let all licensees know th at, regardless of the sequence i
22 of events.
s' C ".v ' L' c~ _c ~ ' ".. = R a'.=.=_.'s.o "= -
- . '.. =.
a' a..
". a_
.=.C"m_c v
_v a
n.
o = _.. ~.
Jer* eral Riocriert. IFC.
25 for example.
I.
e,,' d, c
s i
,9-2 'jwb 51 1
MR. JORDAN:
There are plant transients that 2
require high-pressure safety injection that would not require 3
our immediate notification, and I'll discuss one of those in l
4 just a moment.
5 MR. CASE:
Do you want to turn it over to Ed?
61 MR. EISENHUT:
Yes.
It certainly is a good leadoff.
7 I guess what we'd like to do now is go into the gl short-term actions that have been done already, and then we ' ll i,
9l go through the long-term actions, then those actions we're I
i i
10,
crocosing at this time basically to address these items up i
i 11 ;
here on this slide.
12,
MR. JORDAN:
Okay, we believe that our actions in l
l I
13 terms of I&E bulletins and inspections are going to be a series; i
l 14 that as we learn more from this occurrence, we will be i
15 ;
sharpening and naking more precise the actions we take.
16 The actions that we began on March 31st were, as I
!f" 17 John Davis described, a prompt notification by way of the i
la PNs.
These are " preliminary notifications" that we developed i
19 j within the NRC.
We sent copies of those to all of our l
i
.i 20 licensees.
21 1 Then on April 1st, we sent out a bulletin --
I r
22 ;
CCMMISSICNER GILINSKY:
How did you transmit those?
I
- ]
MR. JORDAN:
Chose were bc h facsimile and mail, 24 l fepending on the arrangement with the plants as far as having wecerat Aeoorters. Inc. '
25 the facsimile.
And the emphasis was on the 3&W plants at tha:
1 11 274
>-a 3wb 52 1
point.
2 But they have been dispatched to all licensees, l
3 and we' re updat_ng those each day as additional preliminary t
i 4,
notificaticns are issued.
We are updating with that new l
s 1
5l 1ssue.
6!
COMMI2CIONER GILINSKY:
Let's see.
You said, "or i
7 nhil."
Do we know that they actually have them in hand?
i g
MR. JO RDAN:
For the B&W plants, we know that they t
9l have them in hand.
I
\\
i 10 COMMISSIONER GILINSKY:
Okay.
t 11 1
- IR. JORDAN:
The bulletin briefly described the l
12 !
Three Mile Island accident, and once again enclosed copies of j
l 13 j the preliminary notification so that that provided the l
1 i
14,
continuity of the inforr.ation at that point.
j 15 The purpose of this bulletin was to alert all 16 licensees of the action and to require B&W plants to co. duct l
17 a review of their f acilities for potential -- for similar i
18 l accidents.
19 '
The bulletin requires a response within 10 days.
20 The bulletin was also issued --
1 1
,1 i CCMMISSIONER GILINSKY:
".Ihen does that period start?
i
.\\LR. JO RDAN :
From the receipt on April the 1st.
72 -]
23 ]
y C ~o., 3.7 : c-
- m.. - >4 :... G -
.r s Lc.., -
Okay.
av L. w 24 MR. JO RD AN :
rhe bulletin was also issued to all
. eceru a corrm. inc.
25 other operating licensees and to plants under construction for 11 6.id
9,-4 j'ab 53 1
operation -- for information, I beg your pardon.
2l Because evaluation of the Davis-Besse transient i
3:
had just been performed, a copy was included in the bulletin.
4l And the evaluation of this Davis-Sessee transient, which was I
5' initiated by loss of off-site power, showed that.'evel indica-i l
6 tion was belcw scale, and this is below the indicated scale i
i i
7' in the pressurizer, for several minutes due to coolant l
ai shrinkage.
i I
9 Now it would be well to point out that that is not I
I 10 :
the orablem that Three Mile Island had with pressurizer level l
t.
i
'l i t
indication.
'dey never achieved this shrinkage because they i
i 12 l never go auxiliary feedwater in.
i I
i 13 The Davis-Besse trarsient was controlled by high-I 14 pressare safety injection, by continued reactor coolant flow, 15 and by auxiliary feed flow.
So the recovery of the pressurizer 16 1 level was in several minutes, and then they were into a normal 17 '
operating =cde.
i l
i
+
18 i In the case of the feedwater transient due to I
i 19 feedwater trip, :or instance, there may be some void formation 20 as a result of even greater coolant shrinkage, and this is i
21 1 once again due to ;ooling frca tne auxiliary reecwater causing 22 ;I this pressure decrease and the consequent shrinkace of coolant.
'l 23 '!
And this causes the level to be lost cut of the pressurizer.
i 24 l It would cause -- since the level was cut of the pressuriner, 3 e tt*F34 A GOOF ff f1. I nc.,
25 ' the cressuriner heaters would no longer be functional 1
O f f"
'j J..L
/-(
'S I
'wb 54
?-o.
J.
1 So during that time, you wouldn't have a pressurizer--
2 I'm sorry, you wouldn't have cressure control, so to speak.
3l Once again, the continued reactor coolant pump fisw and the 4'
auxiliarv. feed cumo ficw and high-pressure safety injection j
I 5!
flow control this transient, and the difficulty is that the i
i 6'
ocerator can't see exactly where water level is for some i
1 7j minutes in the transient.
j I
i 8
Okay, the bulletin specifically required licensees I
l l
i i
9l to review the available data on the Three Mile Island accident I
l 10 '
and to review the NRC evaluation of the Davis-Besse loss of I
l 11 l off-site power transient.
12 l The bulletin also requires licensees to review l
I 13 !
any similar transients which may have occurred at their i
14 l reactor.
i 15 '
The bulletin requires licensees to examine their I
i 16,
controls over safety-related valve positions, and to review l
17:
their operations and maintenance procedures.
I i
18 :
CO.ND1ISSIONER AHEARNE :
Tod *a17 " en specifim' 'y to i
l 19 review the feedwater system valves?
20 MR. JORDAN:
That's correct.
We had a view at that 21,
point that there had been a feedwater valve problem.
22 f; We asked these procedures to be reviewed for the
- l 1
23 j understanding of pressurizer level fluctuations during i
24 transients, so they would advise their operators -- there's EMeral Recortert, IFC.
23 j sCme retraining in hoW the pressurizer level responds during 44 r rm->
1.L A ( I 1
l
?-6 jwb 55 1
the dif ferent;. types of transients to consider primary coolant l
2l void formation, under what conditions they might get voids i
3l formed in the primary coolant, and how they would deal with i
l l
4 !
them.
And we were talking about, at that point, steam voids.
l, 5j Safety features' cverride, and transfer of liquids and gases i
i 6
from containment after a safety injection.
7l So these would be administrative measures that we i
8 were asking the licensees to consider reviewing, or to review, l
9 I beg your pardon.
I i
10 !
COMMISSIONER AMEARNE:
You certainly weren't asking I
I 11 them to " consider" reviewing it.
i I
12 i MR. JORDAN:
No.
We were " telling" them to do it.
l i
I 13 I correct that statement.
i I
i 14 {
The licensees were also required to examine their l
15 maintenance and testing procedures which assure all valves are i
16 '
properly aligned and required equipment is available.
ll 17 j And the last requirement, as we read at the beginning 18 '
of my presentation, was to emphasize the need for prcmpt lo '
reporting of incidents and accidents to the NRC.
20 In order to provide further assurance that the t
21 i provisions of the bulletin are understood and followed, an 22 ;j inspector was dispatched to each of the B&W sites to perform
,I 1
23 o a special inspection related to the bulletin, and to conduct l'l 24 1 other inspecticr.s as a resident inspec:Or until further EMerat AtCo rttr$, I FC. I 25, notice.
11 gg l
1
9-7 fwb a6 The inspection procedure for this special inspec-1 I
tion was issued on Monday, Acril 2nd, to supplement the 2
I instructions of the bulletin.
3' l
,l This instruction recuires evaluation of the 5
licensees actions in response to the bulletin, av discussions I
with operating personnel, increased control room observations, 6
i t
i 7l and that's the end of my discussion about the bulletin in the i
i short-term actions that we've taken.
l 8
1 Do you have anv c.uestions?
9 t
COM"ISSIONER GILINSKV-
'et me ask vou, are we 10,
going to be ecuipped to review their responses rapidly?
t 11 ;
MR. JORDAN:
Yes, sir.
The instruction that we 1
issued also gives us our =cde of review.
13 i l
COMMISSICNER KENNEDY:
And this will be done --
14 '
i I&E, in conjunction with operator reactors?
g 16l MR. JORDAN:
Yes.
The bulletin and the instruc-i 9
tion were issued in conjunction with NRR operating reactors.
i.
COMMISSIONER AHEARNE:
Ed, would you walk down Darrell's points on there and tell us what vou think -- what 19 actions vou think have been taken, if any, *hich would address
.O b
each of those specific, things that he said are things that
,1,
n.
1 3, o ac.carentiv went wrong?
.s il
$1 -l MR. JO RDAN :
The first action was to have the 9
%.TQ
'~
I licensees review their valve 1.neups and to assure that
^4 4
j
-reers 9 ecorters, Inc..
to eculp=ent were done, and
.: =aintenance procecures wl:n regarcs 0
4 i
.f l
A$
r Y:'O 1.s A- (.J i
10-8 jwb 57 l
l 1
we specifically addressed auxiliary feedwater valves.
i 2
CCMMISSIONER AHEARNE:
When they're. told to " review i
I 3
the' valve lineups," will that be clear?
I guess your I
a 4 'i inspector out there --
i 5 !
MR. JORDAN :
The inspector will make it clear.
l 6;
MR. CASE:
Commissioner, when we get to our next 7j series of actions, I think your point will be answered by l
8'I showing them more specific instructions we plan, either as the i
i i
9l next bulletin as our knowledge is increased and we can become 10,
more specific in our instructions to the licensees.
That's t
i 11 !
what we interd to do.
l.
i 12
. IR. JORDAN:
Okay, the first one is covered.
13 {
The second one is not.
That may have been in i
l 14 equipment failure.
We don't understand it yet.
15 Pressurizer level indis tions, we covered.
16 '
The containment did not isolate.
We covered that I
i 17 in our instructions with regard to contair. ment isolation 13 l following the safety injection.
19 COMMISSIONER GILINSKY:
Which is for them to do in 20 manually?
21 !
MR. JORDAN:
At this coint, until we understand each 22 ] of the plant systems, fes.
1 23 1, CCMMISSICNER GILINSKY:
Are instructed to manually 24
_solate?
E *C tr 36 A 000 *ttrs, l'*C.
l t
25 j MR. JORDAN:
That's correct.
11 280 a
10-9 'jwb 58 l
j MR. CASE:
Yes.
This bulletin that he talks about 2
is a general reference to that problem.
The future bulletin 1
3 !
that we're going to get to will be specific as to what to do i
I about containment isolation in the event of ECCS actuation.
l 3l o
l, 5l MR. JORDAN:
The actions in the initial bulletin l
I 6l were based on our understandings as or Satt'rday or Sunday, l
7l and we did cover, I believe, each of the personal type e.;rors i
i l
I 8,.
in a general fashion, and we will sharpen them up with the i
l 9i, subsequent bulletin which is, I believe, the next portion --
I i
10 t well, it comes a little later in the presentation.
11,
51R. EISENHUT:
Yes.
I think mavbe I can --
12 '
COMMISSIONER AHEARN-
Pefore he disappears --
i i
13 l MR. JORDAN :
You're not going to let me off the i
14 I hock on the last one.
l 15 CCMMISSIONER AEEARNE:
Containment did not isolate 16 on ECCS actuation.
I guess you're telling as that's going to
- i 9 be covered in the upccming bulletin?
17 13 l MR. CASE:
It's a general reference to it; look into i
19 1
what the situation is.
20 COMMISSICNER AHEARNE:
And the last two?
21 MR. JORDAN :
The turning off the ECCS prematurely, 0.2 a.
that carticular item was the sub4 ect of a previcus NRR and a
i 23 ; I&E effort advicing licensees that they should not rese: their
.i I
24 - safety injection for 10 minutes, based on similar types of
-Nersi Aeoor ers. ice. !
25 l concerns.
gg g7gy
10-l'0 jwb S9 1
We also reiterated that concern in the bulletin.
2 COMMISSIONER 3RADFORD:
" Previous" meaning when?
l 3
MR. JORDAN:
About a ysar ago.
l
'I apparently didn't work.l 4
COMMISSIONER 3RADFORF :
That l
5 And we " reemphasized" it?
i i
I 6
MR. JORDAN:
In this bulletin, we reemchasized it 71 and specifically instructed the inspectors to examine that i
i l
8:
issue.
I i
i 9 !
COMMISSIONER KENNEDY:
It just turns out, the second I
10 '
one was almost 10 minutes.
I 11 !
MR. CASE:
Almost.
10 minutes and 30 seconds.
12,
COMMISSIONER RENNEDY:
Yep.
i t
13 j COMMISSIONER 3RADFORD:
Uhat caused you to stress t
14 l I
it a year ago?
l 15 MR. JORDAN:
It was the idea that a licensee or 16 11censees in some events had reset safety injection witn.out
- l 17 1 fully understanding the transient that they were entering, or is had entered.
19 MR. CASE:
And our particular concern was loss of 20 Off-site power scmetime for 10 minutes, which would get him in 21 a mode where he couldn't -- if I remember correctly -- get the 22 3 ECCS back on.
23 :l
,d '
- 'C s.....,,:
,de were worried before abcut cerhan_ s nu-i 22 somewhat of a more unlikely secuence, where you compound this
-Eect'ai AtCC r!ers,11 c. l 25 ! situation with, for example, a loss Cf off-site pcWer right i
11 28'8 e
10.-ll 'j wb 60 I
1 after -- accentarily after you reset, as I recall -- to where 2j you could reanalyze, get yourself in a work situation.
i 3
COMMISSIONER AHEARNE:
Just one more thing to ask, i
i 4'
the last one.
l 5!
MR. JORDAN:
Oh, yes.
The bulletin also addresses i
l l
6' the reactor coolant pump operation through the Davis-Besse I
s 7;
transient and the discussion or the less or o::-site power l
i i
3 transient b.y indicating that the reactor coolant cume.s swee.o l
l, 9;
voids or maintain voids, small bubble sizes, as a result of i
t
)
s e
1c loss or pressurl:er levals.
4 3
t 11 i So it was stated that tney snould maintain reactor 6
12 coolant pump operation.
i t
I 13 'j COMMISSIONER AREARNE:
Okay, Darrell.
On.
i L
i 14 !
CHAIRMAN HENDRIE:
Okay, on to the next stage?
i 15 MR. EISENHUT:
All right.
As Ed mentioned, several 16 of these items en this slide are in fact covered ':y the 17 bulletin on the 1st.
i 13 Since that period of time, we have continued to t
19 j reanalyze the situation, and of course we're going to be 20 reanalyzing it considerably a bit more cver the next few 21 nonths.
22 'l Ecwever, we believe cur evaluation efforts have i
.i 23 j proceeded to the point where we're going to be taking some i
I =cre positive steps in the 24 interin.
And the more positive E *C af16 A tOOf ttr1. leC.
j 25 j steps will address several of these.
1 1' 2[33 i
10-12.jwb 61 I
If I could have the very last slide, please.
1l-
~
2 (Slide.)
i 3 i COMMISSIONER GILINSKY:
uarrell, at some point I 1
1 1
4 wonder if you could come back to the previous slide.
Maybe I
I i
5i you're going to cover this.
Would you indicate which of these !
i l
f I
i 6;
six items are somehow peculiar to '&W?
Some of them obvion,Ly ;
i i
t 7l were simply operator actions.
One at least had to do with i
t t
8:
the design c: the plant.
i l
9 I wonder if you could --
I 10 MR. EISENHUT:
Well, why don't we go back to that l
11 !
slide.
It's just as easy to do it at this point in time.
12 Could I go back to the previous slide.
I 13 l (S lide. )
I i
14 '
Redundant emergency feedwater isolated for test and 15 '
maintenance.
CUviously that's not unique.
There 's no thing 16 :
unique 1 bout testing and maintenance; it can always leave a
'l l-17 :i something in the wrong position.
18 Electromagnetic relief 'ralve -- it should be " valve" 19 instead of "value" appears to have failed open.
'Ihere is--
20 that is " stuck open."
We're not sure about the uniqueness 21 of these valves.
We will be icoking as to whether or not 22 } there's anything unique about these valves as opposed :c, say, 1
22 h the valves i n pressuriners and other events.
So that one 24 we're not sure at this point.
11 204 E* Car 31 A 9CCr*f r1, l OC.
25 '
COMMISSICNER 3RADFORD :
But as a rule of thumb,
'l
10-13 jwb 62
~
I valves can stick open?
2l MR. EISENHUT:
Yes, sir, as a rul.e_or thumb they l
I I
3, have stuck open.
And because they s tick open, thev not oniv I
i 4'
open and stick open, they f ail to open, they fail to close, l
5l all of those combinations.
i i
The plants are generally designed with that as an l
6 7,
expected thing that will happen.
On a lot of them, it happens l
i i
3,!
eve rv. vear.
That is something that is expected.
l 9i The cressurizer level indicators appear to cive I
I 10 '
erroneous readings.
Our information at this time is the I
11 arrangement on these plants appears to be unique.
We haven't i
12,
gone through all the plants, though, so we're not sure.
i 13 I COMMISSIONER AHEARNE:
When you say "the arrange-I i
i 14 l ment,n vou mean the location or cressurl:et e i n c. uo. r or --
I i
15 MR. EISENHUT:
' he actual.cin. inc.
ation the way r
I 16 the piping is done with the cold reference leg, et cetera.
i 17'
- 1R. CASE:
It appears to be unique on B&W plants, i
i 18 ;
NiR. EISENHUT:
Unique "to" B&W.
i i
1 19 COMMISSIONER AHEARNE:
How about the instrumentation?
20 MR. EISENHUT:
';he actual instrumentation in the f
21 '
control room I would assume would be the same.
22 COMMISSIONER AHEA? lie: :Icw about ins ide. ' Whatever is
.I 23 used to measure the level in the pressurizer?
11 EU96 a
24 ]
'4R. CASE:
There are two unique aspects in relation
.ry erai seacr -rs. inc. ;
25 3 :o pressure vessel level.
Perhaps the instrument, and I
10-14 4wb 63 J
1
'perhaps the arrangement.
2 It's fair to point out, there was a. staff concern I
I i
3i about a year ago about arrangement which was looked ihtc then 4
and considered not to be extremely significant.
In light of i
l 5
this incident, we're coing to relock at the problem from that i
I i
t I
6t standpoint as part of this review that I'm talking about.
l l
7 MR. EISENHUT:
So to answer the third one, it l
?
I 8-appears the third one may be unique to B&W clants.
i 9i Containment did not isolate on ECCS actuation.
i i
i 10 i That mav. also be unique to S&W plants, and we are presently 11 at this moment evaluating that.
12 COMMISSIONER KENNEDY:
To B&W olants?
Or maybe 13 even to this plant?
I 14 i MR. EISENHUT:
It may be we would be more inclined 15 '
to 3&W plants, however we are looking at that at this time, 16 CCMMISSIONER AHEAPNE:
Would that be a 3&W l
il 17,
re spons fbil ity?
Or an I&E responsibilitv. ?
18 '
MR. EISENHUT:
At the interf ace, maybe in some 19 '
situations both.
20 :
COMMISSIONER AHEA? lie:
Go back to the same questions 21 ;. asked earlier.
When you say it may be unic.ue to the c.lant, is d
22.; it -- I gatber from your previous question it's not clear l
23.! whether or not it's a rec.uirement that we o. lace --
24 i MR. EISENHUT:
.ie do not believe that we have ceni acco, en. irc. ;
25 ! been requiring, on 3&N plants, that the containment isolate on 1
11 2EG a
t
10-lI dwb 64
.J i
I any form of ICCS actuation.
CCMMISSIONER AHEARNE:
- ias it been a requirement 2
I i
3 on anv --
i 1
t 4!
- IR. CASE
I think a better way to say it, is it's I
l l
S' not clear.
We have a uniform requirement that they do isolate.:
I i,
l 6 1 I think the druthers and the thrust of the recuirements have l
i I
7 been to isolate, and we'll have to look at this one again in i
8 light of that.
l i
i I
9, MR. EISENHUT:
The fifth item, ECCS was turned off 10 '
crematurely.
That appears to be a pe'- onnel error.
So there 's -
l i
11 i certainly nothing unique about a personnel error.
1 1
12 Recovery actions is in the same node.
It appears t
13 to be nothing unique to B&W plants.
j i
14 COMMISSIONER GILINSKY:
Is there somehhing about l
15,
these designs that makes them --
i 1
16 !
CHAIR'!AN HENDRIE:
-- more sensinive?
I'.
COMMISSIONER GILINSKY:
-- more sensitive to these 7
18 '
kinds of actions?
i 19 MR. EISENHUT:
That's certainly a consideration 20 that we're looking into in great detail.
The 3&W reactors, l
21 for example, are the only operating, or the only pressurized 22,.
water reactors which have steam generators which have a once-1 i
23 i through steam generator tubes.
The design on the steam i,
i 24 generators is therefore totally differen: Ehan on other plants.
.. meru a cor m. n,c. ;
25 The feedwater flow arrangement through those steam 1
11 287 i
la-16 jwb 65 1
generators are different.
The sizing of the piping and 2!
the sizing of the capacity of the systems are different on i
I 3
B&W than the other Westinghouse and CE plants,
i i
4 COMMISSIONER AHEARNE:
By "different,"
you end un-I 5!meaningsmaller net volume of water?
6' MR. EISENHUT:
I think that's right.
l i
f i
7l COMMISSIONER KENNEDY:
By what magnitude?
i I
i 3;
MR. EISENHUT:
7'm not sure.
We have a lot of l
i I
9i systems people working on that problem right now, and we just 10 don't know.
It's a considerible dif ference.
i 11 i, There are systems dif ference that may well make t.
12,
these plants more or less susceptible, or respond differently i
13 l to the same kind of transients.
i 14 COMMISSIONER AHEARNE:
" Respond differently"?
15 HR. EISENHUT:
I think that's right.
So vou can i
16 l see there are some considerations and differences.
17 !
What we have done is
- have c. eared up for a 18 detailed, long-term evaluation -
"long-term" being over the 19 next couple of months -- looking at the very concerns you jusu l
I 20 ' mentioned, and our review today is a continuing review, cut 21 our review to date has gotten us to the point where we believe i
22 q it is appropriate to take some interim actions on 3&W plants.
1 23 ;
We will be issuing a new bulletin.
And if I could 1
i 24 have the next slide, che one I had a minute ago.
1 E?f*f f al AtOO f ?*f s, 19C.
25,
(Slide.)
11 2b8 I
i
19-11 jwb 66 e
1 These are some items which we are doing which we 2
believe will give us nore confidence in the present situation 3
at the B&W plants.
I i
46 We are verifying at each plant that the emercencv 1
i I
5l feedwater valves are open.
We are doing this by a bulletin i
i 1
6!
to the plant.
It will be followed up by an I&E inspector at i
7' the plant to verify that in fact this is the situation.
a.
Therefore, we won' t be valvinc. out the auxiliarv.
i i
t i
l 9l feedwater system.
l l
10 '
COMMISSIONER 3RADFORD:
Why would you restrict i
11 !
that advisorv. to B&W plants?
i 12 MR. EISENEUT:
Because at this time there's really i
i 13 basically -- we have a general tech spec on all the other i
14.
plants that savs the same kinds o f thincs.
The B&W olants, i
15 l it would be fair to say, have experienced a significantly 16 l bigger transience with the auxiliary feedwater/feedwater systems.
I I
17 '
It would appear they respond considerably different.
I 18 '
We have a normal technical specification which I 19 believe is probably in effect on nost plants, if not all 20 plants already, which says that you should have your feedwater 4
21 ;l system oc.en, vour emerc.,ency feedwater or auxiliary feedwater l
22 'l system, as they call it, open for operation.
a
.m,. '
The inportant thinc. here is we ask them to reverifv.
l 2:
db.a t that is in fact the case, and we will be following it 2p Per:trai AeOOr?tr1.Ir'c..
I 25 ' wi-h IsE inspectors who are at the plant.
11 ges
LO-lb,jwb 67 COMMISSIONER GILINSKY:
Does that mean no test or
-i maintenance during this period?
2l i
3; MR. EISENHUT:
No, it doesn't necessarily.
It I
means if you do any test and maintenance you should have 4
1 extra precautions and extra procedures to ensure that they 5
I are in fact open.
j 6!
i 1
CHAIRMAN HENDRIE:
You observe the license condi-l 7
l tions on one at a time and make sure the others are ready to g
I 9'
go in limited time, and so on.
CCMMISSIONER GILINSKY:
Don't take them out of 10 e-10 ij ;
service.
12 (
i 13 i
14,.
15 16 17 18 19 20 r 21 '
22 ;
23 "
24
- s.,cers A eoor trs inc..
fe cm 1.-
6 v
g I
ll I
eI i
,e I
l Til =m1 I
cr3792 MR. EISENHUT:
That's supposed to be in transients, n'
we are going to caution them not to rely on the level in 3l the pressurizer; that is the indicators or indications alone.
1 i
4 Rather, we are suggesting that they use pressure l
5 indicators on the cressurizer in conjunction with level l
6 indicators in the pressurizer.
We are doing this partialiv I
i 7'
to address the consideration in the previous slide that the i
l a
Indicators appear to be giving erronecus reacings under severe i
l l
9 i reedwater transient situations.
i 10 i
COMMISSIONER AHEARNE: New by giving this advice, I i
11 l conclude that in ccmcarlson, anc comparing the two, the i
12 h i
pressurizer pressure level and pressurizer level readin~es, thev.,i i
I3 l differ in their conclusions?
i l
I 14 MR. EISENHUT:
Yes, sir.
And in fact vou would 3
i 1
15 ' conclude, if you were following the pressure, if you looked at 16 the various different transients going on in the system at 17 the time, you wculd have the pressure dropping rapidly while 18 + the level indicator shcws a very rapid increase.
19 p i
Those two, to an operator in a situation may well 1
'O i. lock and not recognize that in fact those two are going in the 21 'i opposite directions, in a hurried situation.
l
'2 CCMMISSIONER AHEARNE:
And you have scme, at least,
,3'immediate confidence whicb cne?
l l
24 11 2!d.
MR. EISENHUT:
Yes.
- 3.Etctral R eOortof S, 8 FC,-
I ui "l
From looking at everything we've seen ci the transien:
t
69 g
=a 2
1 at this point, we are encouraging them to look at and use the 2
pressure indicators more so than the level indicators, because i
3' certainly in conjunction, certainly not the level alone which 1
I 4;
would be the first indicators.
I 5;
MR. CASI:
Then come some rather more scecific i
t i
6-instructions in the next bulletin.
I 1
7i MR. EISENHUT:
Yes.
i 4
8 And the next item is that if vou 9et into anv.
9, situation where you get high pressure injection flow and the i
I i
10 l system activates, vou should not turn off the system until vou i
i ll i are sure that you have two Icw-cressure injection systems 12 !
running.
13 That means you have brought the system down and i
14 l you are on icw-pressure injection.
l 15 Or, if you are operating with the high-pressure 16 injection Jystem cooling the plant dcwn, it should operate i
17 for at least 20 minutes and until the coldleg and the hotleg --
IS ! that is T-cold and temperature-hetleg, are at least 50 degrees i
19 ' below the saturation temperature of the system.
1 20 Also, if the high-pressure system activates to cover 1
21 i another bullet en the crevicus chart, we are stating that the 22 ll reactor coolant pumps if nhey ar e cn, you should keep ther on t
i 23 with at leas cne in each loop running. That is, the ficw 241should be maintained.
11 2[)2
.;rmsA mems ir c. l i
,e ]
COMMISSICMER AHEARNE:
I think you said that they 4-ll, I
70 mm3 turned or_:_, may, ave turned c:_:_ on one side when thev I
n 2
detected there was a leak, or they concluded there was a leak 31 and radiation was coming cut to that side of the steam l
4, generator.
l l.
i l
5!
MR. CASE:
That's when they isolated the steam I
i i
6' generators.
t t
4 l
7j COMMISSInMER AHEARNE: That was not at the same time l
I t
I al' they turned that--
I..
i 9l MR. CASE:
No.
i 10 COMMISSIONER AHEARNE: All righ t.
I t
llI MR. CASE:
It may 1?ve been the same time, but I
12) it's not t
I, 13 MR. EISENHUT:
I don't think it is the same time.
I 14,t And lastly, we are s a v. i n c. ve rv. sim.olv, that if you l
i 15 !
get ECCS actuation, you should 4.sclate containment.
We are i
16 saying that this can be done manually in the immediate future, i
17; but in a very short period of time -- and we have not decided l
18,t' cn what that is, we should think through the possibilities l
19 ! and the scenarios of what kind of cime and hcw it should be 20 I autcmatically done.
e 1
21 COMMISSIONER AHEARNE:
Now which ones of these ste,s o
22 a do you think might also be relevant to c:her -plants?
a 1
23 ]
Another way of asking that,which ones ought you tc 24 send to other plants?
- w 4ederal A eDor**f t. I nc.
25 MR. CASE:
Understand they all get copies of the 1
71 mm4 bulletin for information.
)
COMMISSIONER AHEAR2iE: But there are specific 2
rections to B&W plants.
l 3I MR. EISENHUT:
The immediate concern, immediate 4{
i I
directions will be that of B&W plants.
We will be looking at l
5 I
I 6;
both the Westinghouse and the Combustion Engineering plants in I
i l
7l the 7ery near future, over the next couple of weeks, to insure l
\\
i that -- we will be decidinc which ones, if anv, need to have S
i i
l a.
i acd1tional measures out on.
9 i
i t
10 '
At this time our decision is that we are not putting i
ij the requirements on. We are sending it to them for i
i^fUE ^tiUU*
l 12 '
I l
13 l We believe from our discussions in f act with the I
t i
f I
I other vendors, that they are certainly lcoking at this and thev la -
i 15 ' may well be ccming down to the same requirements themselves 1
16 independently, even without cur requirements.
That is strictly 1,, 1 a precautionary matter.
i 18 '!
COMMISSICNER GILINSKY: When is this bulletin going I
i j9 ;
Cut?
MR. CASE: We wculd hope tomorrow.
,0 z
MR. EISENnUT:
As scon as we can possibly cet it el'
,,,i physically together and do it.
Hl COMMISSICNER GILINSKY: And it will be referenced back.
g to us?
s~
M 49Cef al A fDorttr1, Inc j 2=.
.\\
u." w u s4 0' TP.
'/ o 7
OT***
m.
~~.
I A
,".s.O}
l f
72
~
s mm5 1,.
COMMISSIONER KENNEDY: Well surelv., to follow I
2 Commissioner Ahearne's point, surely the first one, that is 3'
verifying that the emer encv. feedwater valves are ca.en, ac.clies >
I I
4-to all plants.
l i
l 5;
MR. CASE:
Certainly.
6' MR. EISENHUT:
Yes.
l i
7' The previous bulletin went to all operating B&W i
i i
l r
3 !
plants, but it was also sent to all plants. And in fact it r
l 9'
encouraged the same thing, it said generally vou should be verv '
10 sure that on your emer3ency system such as that, that vou 11 !
have the valves in the right arrangement.
i I
12 ;
COMMISSIONER KENNEDY: Whv. wouldn't vou dust s a v. it's '
J i
13 l I
a recuirement?
l 14 l MR. EISENHUT:
It is a requirement, I think, 1
15 pursuant to the technical specifications of the plants.
16 CCMMISSICNER K2NNEDY:
We are just reiterating?
- I 17 MR. EISENHUT:
The operating portion, the first line, 18 is sort of revarify that in fact that is the situation.
19 CO.NN-.7 5 c 7"mNTR
.K7""u 'v. -
.,_i.' _.dg.".
r
_a s
20 i MR. EISENHUT:
Now, those are the items that we are 21, anticipating doing very sh crtly.
d 22q And that brings us to the bottom line thm we think, 1
23 j as you lock at chese, most of these we think are procedural a
l 24 ; errors, are personnel errors, or design system errors, and which
-rar tr3t P eCC,tef t, I nc, Of ~
aq A. t. e3 h
1 73
(
e 2.
i s mm5 i
1 probably are unique to either Three Mile Island or the B&W l
l i
2l clant.
i i
i i
1 COPliISSIONER AHEARNE:
Before you reach your conclusion 4
4 may I ask you questions.
Sinca you 've pointed out several i
4 l
times that there might be operator errors, have you checked 5l 6'
the operator qualification records?
i I
MR. EISENHUT:
Yes, sir, we did that very early in 7;I g,
the game.
9 MR. CASE:
Harold Denton did it, and as I unders tand, i
i 10 the results were quite favorable.
But I don 't remember the i
11 details.
12 MR. EISENHUT:
Yes, he did it, and as I recall, they 13 !
Were quite favorable.
{
14 '
COM'tISSIONER KENNEDY:
What does " qui te f avorable" 15 nean?
16 l, MR. E IS ENHU"' :
Thev. ' re a well-c.ualified c.rou.c of 17 operators of quite high calliber.
And in fact, our concern 18 actually arose well into the first shift, because the firs t 1
19 1
- c. ro ca. of oc.erators were on duty for a long period of time.
Se o
1 I
i
^0-we were checking to be sure tha t Sey were qualified operators,
4 21 very well-qualified ope rators to run it as time continued.
-l 22,
CCM.'!ISSIONER 3RADFORD:
In the long run, of course, i
,, ' that may raise as 7.any questicns as it answers abo:: operacor i
o n <~
21 qualifications.
14 N'M
.s E?c erat Reoorters, Inc, j 25 i
.R.
EIS E HUT :
It certainly could. And yc. can I
74 a.o r
I.
I 1I certain1v discuss these coints, and we 1 terilly have been 2
discussing them a*ound the clock for the last week.
I i
3 On each one of these items there is a -- it certainly -
i i
4:
Is not on any c: tnese considerations, it is certainly not a i
I i
S' black and white situation.
i 6
COM".ISSIONER 3RADFORD:
To move outside of the 7l
.cactor entirely for a ninute, what is there about what we have a
learned from this tha t if something similar happens somewhere 9
else in the near future, would guarantee that we would not 10 again go 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> with such a misconception of what the nature t
11 of the situation was?
12 MR. CASE:
You mean 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />?
13 CO!MISSIONER BRADFORD:
I mean the 4 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> between i
14 '
Mednesday acrning and Friday morning, when I th ink, at least I
Ic u.. cu u
_-aa.,
ye a n, n.
n.o n
g a. a-
,.m.a.
~ u. a u u. _i g yng u, -.a s_. a_-.s._a,-
a 16 ! ent than it had seered to be on Thursday morning.
I 17'
..o.. :
_c-"- -.. u.. r.,_.
< e l _I, ova-
-"e a.*4ed o# " _4...a
-.. d 2
18 I can just speak fron my cwn personal view, as we were certainly i
^
19 workinc. throuc.h Wednesday nic.ht and Thurscav. and Thursdav. nicht b...98.%.#
w, w - - M.
Q 4
-.M.-
..M. -.$ T 3
gg w
w YM h
O M png g
, d.9 g g 9.gq 9 9..g 4 j w.
- -... ~
g qq
.*n I.
7
- k-3.i ". u a 'w*.4C."i, o.#
Co u_"a~ e,.i.".
a.". V,
" 4 _" C "-.".'.a* "e a.". " a,
c, a "--
G""a"
-i a
'^
v.
. n.. a a
..N
<v.. -
s I
77, 4
II
,C w. *
- a...y h.**,.m. a n.i.. a d.
,Q O p t --
w
-~
.L A.a i
4 V o u ' ^ c '.'s' a "- "". a
~
a' A "1ua '... ~-
- o ~#
a 's's.".* a~
cs.'.- -.c-a--.".":
' '~~4
.e t<* 8 f 38 2dCCf ?f r1. ' FC,
}{
c
%.4.e q a=
%. z. C O.n.a
_4.% t a 3
+m,.,
n u.. a.n.o %.T.a,,
m.,.. %.. a a.T Aa, 2a *
~
m o
so l
.e )
l I
1 call it, things that apparently went wrong, I think you are ledi f
I 2
to a secuence of events where things like a cressure level l
i t
3' e
indicator is giving you the wrong in:ornat;.on woulc.
or course --
4l i
1:. t.ne best in:ormation.vou nave gives vou the wronc. reelinc.,
i.
5 vou're not going to have the right situation.
I'm not sure --
t i
6!
CCPMISSIONER BPJ.DFORD:
My problem is, if in fact 7'
moving more oecole away from the olant sooner had been I
i 8!.
necessarv. -- and I take it from what -- there is n ' t anythinc.
I I
9 that appeared cbvious to me to sugges t that even more could 10,
nave oeen going wrong in terms or r_uel c,amace anc, rue, melting I
i 11 '
inside the reactor than actually was.
If in fact more urcent i
l 12 '
actions had been necessarv., we down here, at least, certainlv.
13 ! weren't taking them on Thurscay morning.
We wa-a
"=4"ly confi-1 i
14 i dent dat things were improving dramaticallv..
Thursdav I
15
=crning --
16 MR. CACE:
You have to re fresh my days.
I 1
17 CC ?!ISSIONER 3RADFOPJ3:
"hursday is de dav that we I
IS !
had a briefing dcwn here, and we seemed to be a couple of hours I.
19 '
away from going onto the PlIR.
And we, I dink, we re pre tty 20 confiden t dat at tha t time things were under control.
21 >
MR. CASE:
I certainly wasn't.
I'm trying to relate 22 3 th a t to your feeling, and I can't, because I believe --
l C '.'."..'".. _ S ' O 'u'.7 7 3 7 '. m' 7 0. 0..'
".vao-
" e d.'. ";
's a - - o.'.'
2 a
n 24 briefed us.
The only dis turbing
-- very dis turbi.7g indi _ation
-i-F: t r al AeOorters. Ific. '
25 l : rerer.ber from that briefing was de verf high reading in de 11 2E8 r
76 e A.
I
\\
i l
i I
1 dome, which was then dismissed as an instrument that was in t '
2l error.
l l
i 1
3:
MR. EISENHUT:
There were basically two things at i
4 that time.
One was -- there were actually two things separate.
I i
5t One was a very high reading in the dome, which at dat time i
i, 6
we said we were going to continue to check, because you were 7'
ge t tinc, it seens like about 10,000 R per hour at the tine in 1
8, the done, and like about 10 R per hour at the cperating deck.
s 9'
As time continued, that reading went down as we were proceeding to.
to watch it go down, and we were $ inking it could t. ell have i
1 11,
been an instrument anomaly.
12 '
Since that time, as the nu-bers actually changed --
l t
13 l for example, frca Thursday on, it has cycled somewhat, and I
la '
it's a reading even of higher value.
We have done a couple of 15 things to corroborate that i nfo rnatio n.
One is an individual 16 went to de outside of the f acility, to de very cp of de 1
17, dome, and tock a reading, and we did a calculation -hrough the 13 i concrete.
So of course, it gives you the feeling dat the re I
19 is a high value dere.
20 l The other thing, however, that eas also at dat eine, 21.! we had a real cuestion mark on, was in f act what was really
!l 22 'i happening in de core, because we had very high de moccuple
'. l I
23 " readings en Thursday.
24 CHAI1"A'! HENDRIE :
Then we had those nigh hot leg-3 meras l eOQ r*f'5. I nc. I e5 '
2 coac leg cir:erences.
4L.4 (d0 om L
i f
79
_e o,
4 L
t
- MR. CASE:
It proceeded from perhaps a steam bubble t
i 2j to a gas bubble.
But it seems to me the steam bubble concern 1
3 was early on.
I 4
FR. EISDmUT:
The steam bubble -- Thursday we were I
5 considering the steam bubble because there was an atterpt i
i 6'
very gradually, over like twenty-four hours, getting the 7;
system down.
g In fact, there were attempts to get the system all gi the way to 4-or 500 psi because the effort at that time was to 10,
get on RERt The information we had at that tine, I think about I
11 l that same period of time is when we began learning that in 4
t 12 l f ac t it was n ' t a s tear b ubble, because we were trying to us e --
l 1.o l the licensee was trying to c.et c. ressuriner scrav.s on to reduce I
i 14 ',
sys tem c. ressure to the c. oint o f c.oinc. to RER.
15 Also, about tha t time, it was when the licensee was 16 1
.I collecting a lot of inforration.
And also at that time, the
.I 17 l information we were getting was very early, in She early t
18,.
stages, and we were first putting it together in scre kind of 19 1 a storv.
1 i
'I 20 -
COMMISSICUER 3RADFORD:
Yes -- al though I suppose 21 1 you have to go through that to answer my cuestion, I'm less 22 0 concerned with what the individual v.isleading indicia were f
i 221, here than with this problem of going a couple c# d ay s thinking 1
24 Eha t things were really -- and I perhaps shouldn't as e the serv necer m. we.
25, words " fairly gccd shape" -- b ut at le as t --
gg
4 77 l
es l
l
- MR. CASE:
It proceeded from perhaps a s team bubble l
2l to a gas bubble.
But it seers to me the steam bubble concern i
3 was early on.
i i
4:
MR. EISENHUT:
The steam bubble -- Thursday we were l
l 5,
consicering the steam bubble because there was an atterpt i
i 6
very gradually, over like twenty-four hours, getting the 7
system down.
1 3
In fact,1bhere were attempts to get the system all 9
the way to 4-or 500 psi because the effort at that time was to 1
10 get on RER' The information we had at that eine, I think about 1
i 11,
that same period of time is when we began learning that in i
12 ;
f act it w as n ' t a s tear b ubble, because we were trying to us e --
1 i
13 '
the licensee was trv.ing to get oressuricer SO.rav.s on to reduce I
I i
14 '
system pressure to the point of going to RER.
4 15 !
Also, about tha t time, it was when the licensee was o 7 ' e c '-d.. c,
=
o '- o -
16,
-..." o -. a '- c...
i
.'nd a'so =' .a.
'4-a,
' '. '. = -
s 1
t 17 '
infornation we were getting was very early, in the early 1
f 18 d stages, and we were first putting it together in sore kind of
.i 19 a stor.v.
20 COMMISSICNER 3RACF?'.D:
'les -- al thouc_ h I s uc c. e e. e q
21, vou have to co thrcugh that to answer my cuestion, I'm less l
22 y concerned with what the individual misleading indicia were 23 $ here than with this problem of going a couple o." days thinking
.a that things were rea,, y -- and - per. naps s n o u s, c n, t as e the
%* er al ReOorters, Ir C.
25 words "fairiv cood shace" -- but at le as t 11 301
79
- e q,
1 MR. EISE:IHUT :
They weren ' t in fairly good shace.
I i,
2l CO}Ci!SSIOi!ER BRADFORD:
At leas t they were getting 3'
better.
l l
4!
21R. EISEIHUT:
I think the gas bubble situation first.
I i
5' cane up probably later on Thursday.
6 CO i'iISSICNER 3RADFORD :
That's exactly the problem.
7l If in fact, for example, the Pennsylvania acthorities should I
a have been getting ready for asking people to nove during those 9'
two days and then -- I don ' t know that we know yet how far 10 away frcn that kind of situation we were -- dey weren't.
i 1 1 ',
They were going along --
I 12 iR. CASE:
I think the answer is, Ccanissioner i
13 i Bradford, v.ou learn f rom exc. erience.
We haven't had nanv of 1
14 !
these experiences, if any.
15 31R. EISE:iHUT:
There 's also one other key event, and 16 that was, the key situation was that de clan: was basicallv.
!l i
17 l stable on Thursdav.
i 18 !
C05t!!SSIO:iER 3RADFORD:
Tha t 's right.
t 19 *
?iR. EISE:IHC :
That was exactly de word that was 20 used, de plaat was s table.
There was no need.
There was 21 time to understand better what was coinc on, and de plant
.l 22 ? was in fact in a node ahere it was cooling, because we were I
i 23 l watching de the=occuples begin to cone down, de plant was i
24 cooling off and there was time, and da was the important cvwe m econn,. s ee.
25 ingredient.
11 302
79 l
a4 l
i I
1 COMMISSIONER 3RADFORD:
Right.
But what I'm saying l
2 !
is that what is tro ublesome to me is that your interpre tation I
i 3
of what was going on in the plan t I don ' t do ub t was a perfectly:
i 4
reasonable one under the time pressures and other considera-i i
l 5
tions that everv.one was onerating under.
But it's preciselv i
I i
6 because you can make a reasonable interpretation, under that 7l type o f situa tio n, that turns out to be at such variance with 3
what the real situation was that we have to think about hua 9;
to be sure that en the next one we would give the right infor-i 10 '
mation cuickly to these around the site.
I i
11 i MR. CASE:
I think the problem was that in the next 6
12 i one, if there is a next one, we all shouldn' t think gas bubble,
i i
13 l because that's the immediate thing that vill come to mind.
I 14 ;
That's the way thinc.s are and vou've c.o t to c.uard ac.ainst th a t.
15 And perhaps I think it might be f air to s ay that we concen-16 l trated too much en the normal course of loss of coolant acci-l 17!
dents as they have been calculated to happen in our PSARs and I
i 18 l our safety analysis reports.
This one didn't follow that 17 pattern, and I think that's perhaps why it took sc=e while to 20 appreciate what we had there.
21,
CHAIPS?! HE'IDRIE:
Peter, I think Se cuestion is a 1
22 gecd one and needs very carefnl locking in to.
The staff t
22 j hasn't particularly been icching at th a t as pe ct,
- a. d I thi nk 24 they would -- you %now, there are o ther mee tings this afterncen i
-e tC tr al ReCCr'ert,Inc. i 25 that they need to get c n to, and I think we cuch:
c trv 10 4
oc<
.e u. c.
80 i
i eB l
i l
1 concentrate our cues tions more on the thines --
i i*
2l l
COMMISSIONER BRADFORD:
I agree, Joe, except that i
3 they ' re not entirely separate.
That is, one of the bases for I
i 4'
continued oceration at other clants at the crimarv level is I
5 cbviously to make sure that th e s ame things won ' t happen in 6
the reactors.
But I think one also wants to be f airly sure 7:
tha t the sa.e things won' t happen outside the reac tor, if 11 3
anything. similar should happen inside.
9 10 i
11 !
12 i
13 14 15 16 17 18 19 '.
20 'l; i
)1.
.i j
7"
- 3 g
ed r ?C er 31 A fCC rit r1, I PC.
- 5
'S l 3
81 I
i CR-J792' l
MELTIER r
~1 7 -*e "1 Il MR. CASE:
And I'm sure there will be studies in
~ ""
I t
2
'b. a "w.
i I
3' COMMISSIONER BRADFORD:
I didn ' t mean to lay that I
i i
4 the resconse end or any other particular area, ei the r.
It's:
i on l
c
- I an agency-wide cuestion.
I 6
CHAIPEAN HENDRIE:
Other cues tions at the morent?
i
/.
COMMISSIONER GILINSKY:
Was there in fact a pri.~ary-I 8
to-secondary leak in one of the steam generators?
9 MR. EISENHUT:
We still think so at this time, t
10 because we have seen a small amount of radioactivity in the I
II '
secondary systen on the B loop.
That loop has been isolated I
t 12 bv the valves in th e sys ter.
But there has been -- in the I3 last few days there has been a sample recoved, and in fact I
t 14
'~i the re is radioactivity in the secondary system, Ehe part tha t ' s 15 bottled up, yes.
16 COfD'lSSIONER GILINSKY:
Was th at in any way related I7 to this transient or do you think it was present before that?
I3 l MR. EISENHUT :
We certainly
.,n't know.
I9 CO".MISSIONER GILINSKT:
And would ' t have made a I
ag j c12:erence if t.na: loop,ad not.oeen closed c_:_?
n 1
Certainly i f 'ro u k e c.. t oc. e r a ti nc. tha t
- l loop, depending on the size of th e failure, if there was 1 S]
t rallure :rcn er:.=arv. to seconcarv., 'ro u co ul c c. e t e. r r.arv 2A co3,.. co _4..c.
-.o se co..e, y 22ce..,
- y. w. _4 -w
- y. o u 2
._. a.,-
4
.w v..
-e
- eral Aeoorters, t sc.
SC i
a ' a r=s for high radiation in the secondary sys ten, wh;ch wc'ld i
1.t 3N
82
- o.
I, o
I L
1 turn off the secondary system. O the rwis e --
l 2l COfU!ISSIONER GILIUSIN :
Suppose you didn't have a 3'
leak and that loop was operable.
Would this course of events 4,
have been dif ferent somewhat?
b 5'
liR. EISE:!EUT :
Not if you didn' t have any feedwater.
l, 6
CIIAIR".AN IIE:IDRIE :
And if you tripped the main pu ps, 7
!!R. E '""NIIUT :
If vou triPced the main cume. s.
3l CO: IISS IONER E L"'.AR:!E :
In othar words, the extra i
9 steam generator steam wouldn't have helped.
10 MR. EISEUHUT:
Dry steam generator.
i 11 ;
"R. CASE:
iicht help more in this phase of the 1
12 ;
transient rather than the other chases.
i 13 !
CIIAIRMAN HE!IDRIE :
0 the r ?
l i
14 '
CO!!MISSIONER AlIEARNE:
I guess the only thinc woult t
15 be that if for some reason the bulletin isn ' t getting out 16 tomorrow, we ' d certainly like to know.
'l n
17 "R.
EISEIEUT:
Certainly.
He '11 do e veg-hing we 18 '
can to get it out.
19
.".R. JCRDA:I:
Yes.
20 CC !ISSIONER DR3.DFORD :
Just in rough terms, pre-21 sumably, whatever decision you are making on the basis of l
22 ' what we ' re learning now would want to be reevaluated once vou O
)
3 m.v.Q. b h.e t S. 4.v. m.
- e. eg g.
- h. 3 e 9 3
-.m. M.4. m a h. 4 e m.
b h. c. h b h. 4 a 5a 4.m...a.-s.
9*
4 a w a
a S
c p e.
ga,
<- w y j
-w-w i
i 24 l
.he secuence that we're concerned with.
xer nexm t une.
- C 'I
- Jb.. o.". do
~.18
'".".4.".I*
- b. _4 ~ " o.i.". *.,.'" ^ 'w' ';."..' ';,..h.=*.*.
~ 1 A '.' '
y
.s m
11~30G i
. o.
3 83 i
l t
i i
1l knew as well as we are likely to know about those-first couple i t
2 of days?
l 3
MR. DAVIS:
It's very dif ficult to say, Connissioner.
i.
4 We right now are olacinc our investigatory attention on track i
1 1
5' to develop these accident sequences in the early days.
But t
6 it's difficult to know.
We have some early interviews with 7-de coera tors.
We have interviewed dem se.caratelv_ and t
S together.
i f
9i, New what we have to do is take what has been develooed 10 '
here and go back and begin t; develop from the impressions of I
11 l de operators what was going on, comparing it with the sequence.
12 ;
B ut- ' t will take some time.
I i
13 ;
One thing we should point cut is i
14 b dat this bulletin that we are planning on issuing will have i.
15 as an a ttachnent a copy of de scenario we basically dust J
16 went drough chronolocv.
i 17 '
CC"21ISSIONER GILIUSKY:
You also have a task croup i
18 l working on a generic review of feedwater transients in 19 '
3&M-designed reactors ?
20 MR. CASE:
't e s.
21 CCM".ISSIONER GILINSK' :
A..d ou gave th x.t a --
?
q i
1 22 ]
'Lo. CASE:
That's about a ten--day ef fort s tarting I
23 > "cndav?
24 ;i
- 7.. c.
s.:
r-
~ _ _ _.. 4 n s.
. narat Hoorters, Inc..I 25 <
COM'IISSIONER GILI:' SKY :
What do you see coming out 11 3Cl l
84 i
e.
I i
9 1l l
of that?
i i
i 1
I 2
MR. CASE:
What I sae moreccnning out of that is the 1
3 marc; ins in the 3&W desie.n to ga.in9 outside the rec.ulatorv.
I 1
i 4
envelope when 't responds to a transient, such as th e feedwateri i
58
- a.. s ' a.". *.
Is-
't close 'o e.~_= _" 3 _i.. o _# ac a-* ab _4 1_4 ~y 4..
~
.y.
6 some areas, for instance, in the arranger ent in the pressuri::er, 7l the amount of water in the sys tem that we were talkinc of i
j 8>
earlier; or is it f ar away f rc= the margin.
I i
9-COMMISSIONER J GIrJ'USKri So this might result in i
10 '
some modification of the instructions that you're giving out?
11 l MR. CASE:
It would more 12.kelv, if something turned I
i 12 :
out from that study would result in design improvements or 13 l design changes -- it 's more in the design rather t.an proce-14 l dural changes, in the need for design.
I 1O COMMISSION"U 37.RNE.
You had cointed out I
ce rh ac. s 16 it y,.ls Ed or Darrell who pointed out -- the: Davis-3 esse
- l 17 !)
.. c de.n ' w _= s n ' ".
_-a_ a_' _' v c," 4 -a_
",_".a_
oa.~.e ao -"._i-N. _4 7 ' _i *_%
+
4 c
a.
m l
IS,
exanined, tho ugh, to what extent --
t i
19
.un..
C.w r..
v.es.
e 20 t CCMMISSICNER 3RADeCRD:
Davis-Besse 2.s shut dcwn at i
71
.w
-. e.~.~~ e_. s
.c~
4
-_m.p_-;
.a a.
w 77 M.o..
.n.m s d.
n 2 /_4 s _.n.e s a e
_4 s s..,., a.
A.,
,e.
4
,.o u.
_a.. o_
t~
w 23 l
... a _4.". *. o_.". a.". "w.
" ". e y." o s e.". *. *. _*.~..e.
c I
24 l r' m..t.u.?
c v '.-
o.
moa s..w.e n.o. n.
r-o,m, _... A a - _. _,,, c' _4.. g
_d-.w
- 4. w,.
s a;&f 30 9eOOrters, Inc,
,... n ;
s..
o
.....a i
"C e4 w
t
..C i
~ e. - 4
,, w, C.,,
.d _4
- a. n u
- v... _. a y e C.4 34 a,f p.o.,. a _i.
-i w.
3 my
-v m
_v
~_
11 308
i 85 l
ea t
l (h
t 1I MR. DAVIS:
Our regional director has contacted t
i 2
their management and ther6 's an agreerent tha t they will not 3
core back up until the matter has been discussed with our 4
regional management, and I believe that discussion is being i
5 confirmed bv.
letter at.creved by us.
c 6
COMMISSIONER AHEARNE:
Jus t the regional ranagement?
7l Perha7s it right be discussed with you folks.
1 a
MR. DAVIS:
When you discuss with the region,
9, generally that means discus sing with us, and that generally 1
10 1 reans discussing with NRR.
11 '
COMMISSIONER AHEARNE:
I guess I d us t wan ted to make s
12 sure it was not ust general.
13,
CC"MISSICNER GILIUSF'.' :
Let me u.'de rs tand.
Whv have 14 !
you singled then out?
15 MR. CA7!S:
That
,Je because of the fact 9.a t 9. i s 16 transient was attached to the bulletin and has attracted a lot t,
17 c- " a ~. '.a. n.'.4 s.
- 1 l a '1 CCMMISSIONER GILINSKY:
I guess I don't understand 19 th a t a nswe r.
Is
- t the pre'ricus exnerience -hat thev.'ve had i
an !
ad a
.y.w. cn' i g - s, m u
- .a go, w h. a *- w u.e 3 4...,-4-.-C..
- w. e -m 3
.a c.m. e.w'a.
4 u
- w I
A4aaava *
- %.a..
.n'e ase v.
~%.. e o s.k.o_ e 9.1 a
- - c e. m e.e o.
m enn m
e-2 o,
79
.y3.
n ' t.& q.
No A r. ' u.
Joa' n-
-b. e e - a. g e... ~. 4. e u b., -
on -~.
y-29
- x. e a.4.., a.
, m.,.
w %. a -n_
- 4. a-c 3. a. =. *..
s c.J.,
- o. C 3,.,,
v.a uw.-
w
. -. n_ - -
4 w--
24
-as 4 ou,-
- a.."~, a - i n... a,
.e ~'-.
'.e. "e do"-"1":.-".-a.
0 4.- c. a.
- ". a. v. '-a
.< tf 34 QtOC f ff f1 l *C,
,e 2.y
,., e,,, _- 4....,,..-,
..,.a,_.
. -,. ~.,...
., m..
....~
11 3CD
00 i
a o-ee i
I i,
i l
I li have done prior to bring it back up.
i i
I 2i CHAIR 20.N HENDRIE:
Other questions?
I 3
(No resronse.)
+
6 4
CHAIPl!bN HE:IDRIE:
Thank you very much.
l 5
COM2:ISSIONER GILINSKY:
Thank you, Darrell.
It was 6
a very good presentation.
12 7-(Whereupon, 2: 3:05 p.m.,
the brie fing was concluded.)
i 8
9 10 '
I i
t 11 14 13,
i L
i 14 15 16 '
il 17 :
18 ll 19 'l l
20 l
,l 21,:
!l 4J i
2b
-r ac tr 3: R e Artef t, i f'C.
25,
11 310
.