ML19253A292

Discusses 790521 Oversight Hearings Re TMI Accident by Subcommittee on Energy & Environ of House Committee on Interior & Insular Affairs.Forwards Committee Task Force Rept & Observations of Representative Weaver

ML19253A292
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Site:	Crane
Issue date:	05/22/1979
From:	Kammerer C NRC OFFICE OF CONGRESSIONAL AFFAIRS (OCA)
To:	Gilinsky V, Hendrie J, Kennedy R NRC COMMISSION (OCM)
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NUCLEAR REGULATORY COMMISSION

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.. n MEMORANDUM FOR:

Chairman Hendrie Comissioner Gilinthy Commissioner Kennedy Commissioner Bradford Ccmissioner A arne,

Office of CM, d' rector

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Carlton Kam.erer FROM:

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SUBJECT:

UDALL COMMITTEE OVERSIGHT HEARINGS INTO THREE MILE ISLAND On May 21, 1979 the Subcommittee on Energy and the Environment of the House Committee on Interior and Insular Affairs held oversight hearings on the Three Mile Island accident.

In addition to Chairman Udall (D-Ariz.),

Representatives Markey (D-Mass.). Vento (D-Minn.), Bingham (D-N.Y.), '

Edwards (R-0kla.), Sharp (D-Ind. i, Miller (D-Ca.), Cheney (R-Wyo.),

Weaver (D-Ore.), and Bereuter (R-Neb.) attended the hearing.

After an opening statement by Chairman Udall (. enclosure 1), the Subccanittee received a report from its task force investigating the TMI accident. the task force report and the personal observatiens of Rep. Usaver are enclosures 2 and 3.

Mr. Carl Michelson of the TVA then described the TMI transient. Mr. Michelsen indicated the TMI accident was a ccmbination of errors of design (a " loop seal" arrangement connecting the pressurizer to the primary system), analysis (insufficient analysis of small break loss-of-collant accidents),

procedure (the operators' attention was keyed to pressurizer level indication).

and judgement (other information en reactor status was available to c;erators but was initially i:;nored).

Mr. Michelson also made +he following recommendations:

o That PWR's be equipped with gauges which measure water level inside the pressure vessel, o Fermal procedures should be established to assure that design problems are brought to the NRC for review.

o These should be a system for bringing dissenting views cn ne.: designs to the attention of the NRC.

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799 300

. The Commissioners, Dr. Mattson. Mr. Canton, Mr. Davis, and Mr. Stallo apceared to answer questions concerning the NRC's performance in responding to the accident and the Commissioners views on policy changes. The Commissioners

' are also re;uested to,7envide answers to written q::astions by 'Jadnesday a.*:stncon..':1y 23.lgM.

The cues tions.iere deli /ared to the Cc.7aissi:ner.:'

Of fices yesteraay.

The Subcommittee will continue the hearia; at 9:45 am May 24 in room 1324 Longworth House Office Building. Representatives of Metropolitan Edison Babcock and Wilcox, the Atomic Industrial Forum and the Edison Electric Institute have been invited to appear.

Enclosures:

As stated cc: OGC O P E,f-ED0 MPA NRR RES IE 50 SECY NMSS

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e ENCLOSURE 1

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SUBCOMMITTEE ON ENERGY AND THE ENVIRONMENT OVERSIGHT HEARINGS ON THREE MILE ISLAND

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---i-g, OPENING STATEMENT

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HON. MORRIS K. UDALL, CHAIRMAN

~MMi Monday, May 21, 1979 q=:

This morning's session represents the first in a series jg 4Mi of hearings and subcomittee activities conducted as part e...

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of a comprehensive inquiry into the status and future role t

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of nuclear power in America.

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Our Subco==ittee inve'stigation was triggered by the U3}

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occurrence on March 28 of.the most serious accident at a igf.

nuclear plant in the history of commercial atomic power.

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Coming on the heels of other significant events, such as ims

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the 5 plant shutdown and the partial repudiation of the

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Rasmussen Report, the Three Mile Island incident convinced 5

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me that the time had come for a serious reconsidera*dca %

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.EE the use and regulation of nuclear power.

This Subco=mittee

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is charged with primary responsibility in the House for

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assuring that cc==ercial nuclear power does not present

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an unacceptable risk to the public's health and safety.

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As such it is not only appropriate but I believe mandatory that this panel convene the kind of hearing we will conduct TN5 g.g today and the full investigation into a variety of nuclet:

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power issues we will pursue in the coming renths.

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Today we will hear first a report frcm a task force jl.l I appointed, in consultation with the minority,

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to inquire into the facts of the TMI accident.

This group, ably chaired by Representative Jim Weaver, has interviewed N

x=n 15 witnesses over the last two weeks in order to gain a first 4:.3 hand understanding of the TMI accident sequence and recovery g::-

operation.

The task force report includes the panel's consensus "E-understanding of these events and identifies issues that = erit 3:

further review.

Pr. Weaser and Congressman Cheney will offer 3R t:h5 the report.

I want to compliment them and the other members Gzr

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of the task force for their hard work in completing their

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assignments.,in this short.two week period.

Given the countless j.5!

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demands on a Member's time, it is a remarkable indication of E

these members attention to their responsibilities to this s r-Subco=mittee and the House that they were able to carve out 5

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S,.;. e the time to conduct these lengthy interviews.

For their EE i important efforts I want to thank my colleagues Mr. Weaver, f.:'jp i

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M.r. Cheney, Mr. Runnels, Mr. Lujan, Mr. Carr, Mr. Marriott, y,.1.. 2 I

Mr. Markey, Mr. Edwards, Mr. Kostmayer, Mr. Vento and Mr. Huckaby.

Following the report of the task force we will receive

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ar a chronology of the accident sequence from Mr. Carl Michelson

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an engineer with the Tennessee Valley Authority.

Mr. Michelson has been involved with the analysis of a Babcock & Wilcox

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. r-reactor now under construction at the TVA.

Mr. Michelson is also a censultant to the NRC's Advisory Cc=mittee on Reactor Safeguards and has spent a good part of the last two =enths analyzing the Three Mile Island accident.

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E I would like to note that Mr. Michelson wrote a memorandum f

in early 1978 which suggested that in some circumstance reactor operators might be misled into prematurely turning

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off the emergency core cooling system.

Since this seems we..-

to have been a major part of the problem at Three Mile Island, I would like to know why it was the Michelson analysis does not appear to have been taken more seriously and why it was not more widely distributed.

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Finally we.will receive testimony from the Chairman cy;Z; n:: ^

f=[ =f and members of the Nuclear Regulatory Commission.

While the accident is still under investigation, I am certain that h.1 -

r the members will be interested in the Commissioners' observations p?"~

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p about what happened at TMI and what it tells us about the fML

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lis way we regulate nuclear power.

In addition, we will be interested b-.L.

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in the status of the NRC's inquiry into the accident.

I understand that appropriate ser.ior members of the NRC's

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pp.:-;gt V:4.2G As I indicated at the outset, today's hearings is only (ij[

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the beginning of our efforts.

We have released a tentative

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schedule of hearings over the summer months that will allow T-L g.

us to look into the full range of nuclear issues, including r :---

ru licensing and enforcement, nuclear waste, tre economics of I

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nuclear power, Price-Anderson and energy needs in general.

L(6-Thile there are understandable and legitimace pressures on the

. embers of chis cc=mittee and the House to react immediately tc the TM-accidenc, it is my hope that significant changes j.:

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I-in existing policy would ccme after this Subcc==ittee carries out t '.

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its hearing schedule.

I reaffirm therefore my intention

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to convene sessions of the Subcommittee in early fall to

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9'E consider legislation affected nuclear policy and regulation.

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We tu.rn now to our colleagues Mr. Weaver and Mr. Cheney.

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As chairman of the Task '

and having been ::i Ere.

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ur 3fi-Er Three Mile Island, Unit 2, Is E ::.e to give the ::-

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and review.

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background is the movie, "The'

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plant is in the throes of a p " _

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ne plant, played by Jack Lemm^..

1: eves there is :-

' anger and attempts to tell the trut p was: is happenin; he plant.

A public relations man for the% g?g&

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non tells the & &

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The movie makes it cicar -- a '

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=an is lying.

f As our co==ittee toured.,,

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oppor-tunity to talk with Mr. Jack He 3

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ne TMI M'$g accident.

His cocnents to theMC( me:ia in those f-s of

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It seemed as if Jack Herbein had the Same scriptwriter as "The China Syndrome".

I found Jack Herbein to be an open, intelligent, energetic man whom I instinctively liked.

I was curious as to what his' reaction had been to the movie and I asked him if he had seen it.

He said he had, a few days before the accident.

"What did you think of the movie ?",

I asked him.

"I liked Jack Lemmon" he responded.

"What did you think of the PR man?"

Jack said:

"I didn' t think he was worth a dann."

h*e were walking down a concrete corridor together and I could tell that Jack was thinking about his last remark. Then he turned to me and said; "But ycu know, a week later I was doing the same dann things."

Jack Herbein struck me as a highly capable and honest person.

There is only one conclusion I can draw from all of this:

People are i

placed in the unfortunate position by the situation and by this j

technology where -- within the bounds of " normal behaviour" --

they are forced to lie.

Something is deeply wrong when that is the case.

I believe the Task Force through its recorded interrogations and specific observations established beyond question the following factors contributing to the seriousness of the TMI accident:

1)

Operator or operator training error; 2)

Design error; 3)

Malfunction of equipment; 4)

Violation of NRC regulations; and 5)

Conmunications confusion.

99 307 O

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Furthermore, the lack of proper monitoring of radioactivity release, the extent thereof and steps dealing with both was by no means conclusively establisned, but grave doubts l'_

in my mind about this critical matter and'I urge further investigation of'it.

As to operator error, let me first say that I was very im-pressed by the calibre of the people operating the plant whom we interviewed.

They were bright, informed and in my judgment, qtilte competent.

Mistakes were made.

Pumps were turned off that--all things being known--should not have been.

Readings of signals and events were misjudged.

Observations which should have been made were not =ade.

But as the Task Force listened as they related their first hand descriptions of the events, I was not at all sure that others would have acted differently.

If they had been trained for this specific series of events--which they were not--it is likely that the degradation of the plant would have been lessened; but--and I em-phasize this qualifier--one or two differences in the series would have plunged the operators into the same desperate straits.

Given the manifold potentialities, variatinns are not j ust possible, but likely.

I saw no operator error not closely related to design or equipment error and, therefore, it would be impossible to assume that merely more training could preclude accidents.

The possibilities for error are simply too numerous.

Design error is more difficult to pinpoint but it is never-theless there; Mr. Michelson's analysis is evidence that it is recognizable.

The lack c f methods to measure coclant level in the 799. 308

reactor vessel is one important deficiency; there are others.

There wcre seversi equipment malfunctions but the most impor-tant was, of course, the failure of the power-operated relief valve on the pressuri:er to close.

The sigrni to the operators that it was closed did not relay the proper information.

This failure lies between equipment malfunction and design error.

There was a clear violation of_NRC regulations in that a valve on the auxiliary feedwater line was closed and had been closed for some time.

It is unclear what part this violation played in the further degradation of the tant.

It did lead to confusion.

In any event, it certainly startled the operator who, upon discovering it eight. minutes into the accident, shouted. "The twelves are closed!",

Communier.L1;P.s can only be described as a mess.

From phone calls to the NRC which will only be understood once the thousands of telepnone tipes are studied to the wearing of respirators in the control room which of ten interfered with normal verbal inter-changes, the relaying of important and appropriate information to the necessary persons occurred in a state of confusion.

Thcugh the communications system can certainly be improved upon, I have to wonder if it could not also be worse if, for example, radioactivity were more heavily to contaminate the control rocm.

As I review the Task Force's material, the question I ask more insistently than any other is: Can the lessons of TMI help prevent such accidents in the future?

First, a matter paramount 1y clear from cur investigation, 799 309

practically no one--the operators, the designers, the NRC--ever thought such an accident could happen.

Instruments and gauges that could.ha've Fea"sured'the extent of the damage in the reactor vessel and in other areas of the plant were sct at levels too low to be of value: simoly because no one thought higher readings would be necessary.

Operators were not trained for the events which did occur: simply because no one thought they would occur.

They kn'ow it now.

Can we change?

Can we retrain or more intensively train operators?

Design plants better?

I cannot answer these questions with certainty.

But I can say with certainty that the accident at TMI 2 was NOT a next-to-impossible fluke.

One valve, just one of

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dozens,, stuck open.

It could happen again; indeed, this very valve stuck cpen before at the Davis-Besse plant; but so complica-ted are nuclear plants--as the plant supervisor told us, "So many.

papers cross my desk"--that none of the operators that we inter-viewed had heard of the valve problems at Davis-Besse.

At Babcock and Wilcox plants, transients--a euphemisra for a minor-accident--occur almost four times a year.

But B 5 W is not alone.

Almost 2 such accidents have occurred yearly at Combustion Engineering plants also.

Given one or two other events, these transients could degrade into an accident as terrible as TMI.

Indeed, TMI could have been much worse, although it is still un-

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clear rom cur investigation hcw much worse or exactly wha: : vents would have had to occur to make it worse.

Our investiga:icn of the accident at TMI revealed a matter which rec.uires further investigation: the vulnerability of such plants :: power failure, both from within and withou: the plant.

Several expert witnesses, when asked what could have happened if 799 310

power sources failed, suggested the probability of a complete failure of the plant (to a melt down).

What will happen to TMI 2 now?

No one knows.

How badly damaged are the fuel rods?

No one is sure.

Can they be remo'ved someday?

No one is positive.

These questions, and their aerolexing answers, pose the fundamental problem of nuclear plants.

If something goes wrong with an oil steam generator, you take a monkey wrench and fix it.

If something goes wrong with a nuclear plant, the entire plant is in jeopardy, the populations around it are in danger, and, if the accident is serious, the loss of the plant is the probable result.

This, causing long term disruptien of power supplies, and enormous loss of, investment.

Three Mile Island has proved the extreme vulnerability of nuclear power.

Therefore, I ask the committee to consider the fact that the nuclear industry has had 25 years to perfect its designs and i

i operations, has spent billions of dollars in research and develop-1 ment, and is still brought to its knees by a valve malfunctioning and one or two inappropriate responses.

The responses made amid the alarm and din of the accident itself, when fif ty to one hundred alarms were being registered.

As President DeKiemp of General Public Utilities told me, "With that many things going on, the operator could not be expected to be on top of everything."

I have of course asked myself these questions and must conclude that an accident such as occurred at TMI not only could happen again, but is likely to at any time.

No one can say--certainly not myself--

with what frequency or at what odds, particul.arly when that most ccmpendious of all nuclear safety research, WASH 1400, placed the odds of the TMI accident, according to the Ccngressional Research

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Service, at 6 in one hundred million.

Lastly, I retur.1 te the concern explored in the beginning of my testimony: have we been told the tru th ?

Jack Herbein's remarks are on the record.

He must live with them.

But the remarks of the NRC are also on the record; on the record of this committee, as a matter of fact, on Thursday, March 29, the day following the initial accident at TMI.

Th ir ty-s ix hairs af ter the accident began, thirty-three hours (we know now) after very serious damage had occurred to the fuel rods, the NRC testified to this committee that, while a significant accident had l

occurred, it was not grave and cverything was then under control The NRC were not the only ones in the dark.

Operators and l

engineers involved from.the start of the accident I

repeatedly told I

the Task Force they did not know the extent of the damage--the degree of~serions danger--until one or two days after the dama e

had._ occurred.

For example, t

according to the testimony we received, the t

i pressure spike (which we now know registered a hydrogen explosion i

in the containment) was considered by many, if not all, to be a minor gauge malfunction, not an event which actually happened Many other symptoms, signs, and events were ignored or disbelieved acco r-ding to the testimony given to the Task Force.

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Yet all this time inside the reactor vessel and inside th containment, a radioactive cauldrom was erupting dangerously.

Appropriate si s either were no aken or, possibly, would have done no good if they had beun.

Testimeny to the Senate Ccmmittee on Environment I

and Public Works by President Diekamp of GPU implies the reactor system was of control during this time:

out Diekam,o says the operators verked 799 312

to "re-establish control."

Eventually, they did.

But the plant was out of control: the operators did not know what was happening inside of it.

They could not 1.cok in.

They could not go on.

Measuring devices and gauges had either failed or were non-existent, were set improperly or in the wrong places.

Were they actually ignorant of the extent of damage, of the degree of danger?

If they were, it is a terrible indictmen*, of the entire technology:

to confess that in such a highly engineered, costly, and potentially dangerous facility as a nuclear plant, they did not know what was goir.g on at the most critical time.

Or perhaps they did know and did not tell the truth; are still not telling the truth; indeed, tried from the start to cover up the extent,and significance of this accident until they could assert cer. trol and stability.

It is certainly one or the other.

Possibly some of both.

I prefer to believe that it is the former: That they did not know what was happening.

And if that is indeed the fact, then the indictment stands.

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799 31:

ENCLOSURE 3 SUBCOMMITTEE ON ENERGY AND THE ENVIRONMENT OVERSIGHT HEARINGS ON THREE MILE ISLAND f...

L REPORT TO THE Sinn OMMITTEE BY THE THREE MILE ISLAND TASK FORCE'

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Monday, May 21, 1979 em=

Chairman Udall established the Task Force to inquire into the accident at the Three Mile Island nuclear plant

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imi and the response of the licensee, Nuclear Regulatory Commission

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and other officials.

In closed, info.m..al sessions, the Task 5 e.s

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Force interviewed representatives of the NRC, including

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me bers of its inquiry team, Metropolitan Edison, Babcock &

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Nilcos, and Mr. Carl Michelson, a nuclear engineer with the

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Tennessee Valley Authority.

A list of the members of the

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Task Force and interviewees is appended to this state =ent.

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our purpose today is to report to the Subcommi". tee.

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A definitive statement on causes and remedies of the Three

42 Mile Island accident must await completion of the inquiry g#fM rsur.L c... =

of the Presidential Commission and the Nuclear Regulatory J

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We believe 4.t important, huwaver to state our Tl.

preliminary observations in order to alert the Subeccmittee and other investigators to what we believe to be significant

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I will outline the significant events of the accident E!)ii '

sequence, as the Task Force has been able to identify them, k._..

and a conceptual explanation of the types of fai'ures that g..

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.ay have occurred.

Folicwing that, I will provife scre t;.

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praliminary observations of the Task Force.

Subsequent

o these cc==ents which represent the consensur of the Tas::

799 314 r

. Force, I, Mr. Cheney and others will offer their personal

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observa tions.

Later Mr. Michelson will explain in detail the accident sequence.

fArc aa SIGNIFICANT EVENTS IN THE ACCIDENT L=--

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1) Auxiliary feedwater was blocked from the " secondary cooling system by valves closeC prior to the event.

Whether the closure, a violation of NRC regulations, directly contributed 3

to the exacerbation of the accident is a matter of dispute.

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2) The Pilot-operated Relief Valve (PORV) located on E,.=+

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top of the pressurizer opened as designed, but due to an as

[, yet unknown mechanical failure, stuck open. Its failure ?;;M to prevent leakage from the pressurizer -- until a blocking b w..- valve in series with the PORV. was. closed at 2.3 hrs. -- . Irei=- sr ~ y::!.!.;. was a (if not the) major factor in the accident cequence; p-f.c:.. the reasons for the operators' failure to close a dcwnstream C,, 4.is. block valve until well into the sequence are complicated tat es and controversial. d.Z F==;

3) The design of Sabcock & Wilcox steam generators

[!!E &If reactor results in more rapid drying out of the secondary i+': - =m; steam generator than in other manufacturers' pressuriced (({ water reactors. This may have reduced the time available

yg for operators to respond to the situation, although the fjNM e

t:: significance of this, if any, is not clear to us. E' - ::--=

4) The level indicator en the pressuriner was not an adequate indicater of reactor water level during this event.

I;. ?- This led to misinterpretation by cperaters of the significance of the pressurizer water level. They relied :pon it as an 799. 313

Vr:w- - indicator of the reactor being full of water and consecuently they limited injection of emergency core ccoling water into the reactor, which led to primary coolant depletion and the - - + uncovering of the core. Debate continues as to whether the _}, operator had sufficient and accurate information -- other y;.. than the level in the pressurizer --- to infer the actual -g =e reactor water level. r.?"

5) The operator shut off the reactor coolant pumps f_'.

p.::.= (RCPs) possibly due to concern that pump vibrations would

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T.*.' 515 M.i damage the pumps. Doing so reduced cooling of the reactor . i-2:.t. core but testimony indicates this may have been a required ac tion. ji:. E...I.

6) Containment isolation occurred upon pressure actuation,

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-p as designed, but after radioactive water from the primary EE E.. coolant system had been automatically pumped into the auxiliary $5 E:2 building, allowing releases to the a rosphere. g.

7) While several operators and supervisors watched a strip chart, a 28 psi pressure spike occurred in the containment jf.d building at approximately 1:50 p.m. on the day of the accident.

.ff, Conflicting cestimony on this event and its immediate and "E subsequent significance make it a controversial issue. N

8) Throughout the early hours of the accident, the operators could not readily interpret core temperatares E.

t :. f rom the in-core thermecouples. 799 316 w

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-4_ CATEGCRIES OF FAILURE ?!.":: The Task Force believes that it is helpful to look y.:. ? :.=. at the Three Mile Island accident with certain categories a.. of types of failures in mind. We do not imply Ebat all the 5+*

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possible failures contributed significantly to the events b[hk di..;. at TMI, but for the Subcommittee review we present what we .55-~ believe to be a breakdown of kinds of failures that can occur. "r- " int

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Design error would encompass plant features which allowed f=EE

e. n for insufficient safety margins, inadequate instrumentation,

[][ [n =- or sys,tems that were not properly designed to cope with certain [.) g= w -- y;p:]= emergency or accident sithations. = Equipment malfunction and' faulty construction encom: asses p- - : Eu E =u-equipment. malfunctions and consd$uction errors that contributed .bbh .:.+. to the accident. ~~ ~~ g Ev. Prncedural errors are those resulting from procedures N3]5 '7:!2 inappropriate for the circumstances. These might include (..jk. .d. !:::=.: p. such things as incomplete check lists or written instructions t EE E ~~5 = that cause operators to take actions that exacerbate the }#{b situa tion. _. _::=- .:=-- Operator errors includes situations where an operator

((i acted in manner different from that which would have been 5:L._

= =: M: L-expected frcm a licensed operator who had sufficient info rma tion - is m=--- to take the appropriate action. ' = w.... =:. =. We have heard testimony suggesting that the reactor ]~j 1 cperators should have been made =cre clearly aware of the following: e m 799 317

=:

==, -- The tendency of the Power Operated Relief Valve (PORV) to stick open. =-- ';. a--.. -- The fact that were was no positive indication of 2-closure of the FORV. "'5 -e =-- -- That the pressurizer water level was not an indication _l.-.[.. of full primary coolant systen when portions of the primary i=ijE u- ~ system were at temperatures in excess of the point at which boiling might occur. . ~ - - - ~ - - -- That in case of doubt as to the existence of a leak M .2.......- in the primary, high pressure injection pumps should

55.-

be 1 eft on. [. =..Z- = = e:e We received information suggesting that the lack of

3i

. =. instrumentat' ion to measure and clearly indicate the following [i ljf t ' '.- n;- may have led to operator actiong.that were inappropriate i:,=e. for the conditions that existed: t *"K ** f, ;:-.;- Reactor pressure vessel coolant level.

• t'::=: * "

s~ h il.r. Radiation level in containment.

== ~ '"" I : " -*."* Existence of fluid flow and the high temperature b.= =5 -55 k =# i.n pipe leading Irem pressurl:er. t.- ::= =- Positive indication of closure of Pilot Operated = =- .. = - - "== t Relief Valve (PORV). u.. In-core temperatures indicating presence of superheated -., - '= s e=- n steam or chemical interactions between fuel cladding !E..-. .~. and steam. Wh l:: - Integrated measurements of ecolant injected by high $~. pressure injection pumps (HP-). -- Integrated measures =ents of rea::cr coolant letfewn. -- Whether steam bubbles may have developed in the reactor primary. ^ gy-jj d.. f

The Subcommittee heard conflicting testirony with regard to the following:

• h5 Whether operators had sufficient information to know

.. _ M*\\. that the Power Operated Relief Valve was stuck open. =?-- --[ 5; Whether the operators had sufficient information to - a know that they should have allowed the High Pressure ..g.m; Injection Pumps to inject water into the primn7 at 95f+;- zE fell capacity. .s:s C:.'.T.i.E. Whether the operators had sufficient information to Fn:== infer that there had been a hydrogen burn or explosion ,t:j{g at approximately 1:50 p.m. on March 28, and the impact hN C;:p of definite knowledge of this event upon decisions by h m-E=s, planu managers. =-- The time at which the operators had sufficient +--; information to know that more than 1% of the fuel rods = r.;

gg N

had suffered cladding failures. u g== p.is -v The extent to which there was danger on March 28 and gz EU i;9 iit the following several days of equipment or instrument %:-M failures that might have led to melting of fuel. y m.: - OTHER ISSUES 3 g.-- There remain many other issues which the Task for.ce was g[=g s+ .=.M

== 7 not able to explore adequately, but which are very ir:portant .:.[.. .E . 2-aspects of the accident and the events surrounding it: ^s c L". [.. 799.31E

-7_ f.'.. 1) The significance vis-a-vis Three Mile Island of r1 incidents at other Babcock & Wilcox reactors including the [j! n transients at Rancho Seco and Davis-Besse, and the questio.2 of Whether information concerning these incidents had been

_.7" l-adequately analyned and disseminated.

t.-.= v: :::

• n 2)

The response of Babcock & Wilcox to TVA's April 2, 1978 yg, letter forwarding coc=ents of TVA engineer Carl Michelson [M ~ ~ =; [{i=: regarding decay heat removal during a very small break loss f+ E*. of coolant accidentiin a Babcock & Wilcox rea~ctor. El r: 3) The frequency of the Pilot Operated Relief Valve E!.li ,rg = (PORVs) failing to open at TMI-2 (one previous occassion) and ik+ g -,- the responde by the licensee, vendor and NRC to this problem. M-+ ?!"# 4) Concentrating on developing an understanding of the syk fr accident.and recovery sequence, the working group did not K += t:--- J.h[: !f explore the questions regarding the communications between and the decision-=aking process of the State and the NRC.

g::--

This issue, however, is a crucial ene and should be E+ g. - K_ explored fully. [3T

51..F=.

5) The Task Force identified issues involving both s_ cc=munication between the licensee" and the NRC staff as well =-- as questions regarding the role of the NRC in decision-making during the accident and recovery operatiens. It is apparent, for example, that in the early stages of the events (Wednesday afternoon) impcrtant infcrmation regarding the pressure spike and associated events which indicated a hydrogen detonation or hurn was, in fact, for q.. 799 320 l

• =g

T- --

reasons the Task Force was unable to identify, not conveyed to the NRC's incide,nt response cent'er. The hydrogen detonation or [;{, burn may have been an indication of substantially greater core damage than Federal 7r State officials had believed up to that

g.

=; point, or indeed until Friday. While it is not clear that

=

the failure to transmit this information contributed to any

.:.s 7E increased threat to health and safety, the failure did serve to diminish the NRC's ability to understand what was happening

}:[.y. in the reactor and it denied both State and Federal officials 25 k:E. informat' ion that was essential to their consideration of

h p=_-- -

the need for evacuation.'

... [2

• 2G-The Task Force recej.ved testimony indicating that following p;+;;3:

c --

the accident there existed no clear procedures spelling out !i.t - the role of the NRC in its relationship to the utility with . [.E== respect to how decisions regarding reactor operation were to IY i#EE be made. A working relationship evolved that may or may not ggg [!!E fE-be considered satisfactory upon further analysis. j I::?5= 6) The adequacy of radia+-ion monitoring in the area 9.7f' [.1. _E .'A surrounding the plant was not examined but is, of course a "s 7ls - very significant issue. . w -.

~~ **

iiE &5-E.Z

--.g inh.

=-- I.* : * ** . 4:: L.. .6 .e

=.. l.'... ;. APPENDICES !? F- - =::.

..s.:

se THREE MILE ISLAND TASK FORCE Mf;;_; f i:--- :ii

E MEMBERS iiM isF 5#.

.9$'Is Hon. James Weaver, Chairman Hon. Manuel Lujan, Ranking Minority .. =... Ll Membe.r 6: = Fi? Hon. Harold Runnels Hon. Dan Marriott !=== EZE Hon. Bob Carr' ??.=:~.si.5 Hon. Mickey Edwards MM ism Hon. Ed Markey .... ::m: Hon. Richard Cheney ils Hon. Peter Kost=ayer ~~ ~~!!.4 ? n+=;-- l Hon. Bruce Vento

.h-~.

EM Hon. Jerry Huckaby '!.:.2.f [ E.' a. t.f.i. 4i.+: W

=.

'.._h.7. ~i ii;d I w=. $!.5b ' E*==: s:::.2, g. ::= ..+:

"*?

hl*

ii!;it'

=.::. .I".... . 1..:.~._l._.

• *- h

+.$? ?.'*8i 4e e. ) e L {.- i~I. I

WITNESSES l 's ~~~~~ t - - -- 2 jf" Name Date ~"is Mr. Harold R. Denton (NRC) May 4 , Director, Office of Nuclear RegulNtion .Y 3 Regulation .m=

• "~"

Mr. Roger Mattson (NRC) May 3 [ l[-~ Director, Division of System Safety, Office of Nuclear Reactor Regulation i:rr ! p[y2 Mr. Vic Stello (NRC) May 9 Director, Division of Operating Reactors .K Office of Nuclear Reactor Regulation ![if. i -.-- \\t Mr. Darrell Eisenhut (NRC) May 9 j,l742 Deputy Director, Division of Operating , ;;,]~ R'eactors, Office of Nucles Reactor 'I.tfl. Regulation fis SQ= Mr. Carl Michelson May 10, TVA Nuclear Engineer ~' !".5.. 7: Knoxville, Tennessee P;if I T=- M. James Creswell (NRC) ,May 10 NRC TMI Inquiry E:s. Region III 5"" Office of Inspection and Enforcement ,ylTf 5@ .. kib '~ Mr. James Higgins (NRC) May 10 Region I Office of Inspection and Enforcement f."

== Dr. Charles Gallina (NRC) May 10 Region I 53" Office of Inspection and Enforcement Mr. Craig Faust May 11 Control Room Operator r--- TMI Unit 2 += Metropolitan Edison Co. ' ~ ~ ~ General Public Utilities ~ E 799 323 '*.5*4 8-em9 4

Witnesses -(cont'd) Mr. Edward Frederick May 11 Control Room Operator J' TMI Unit 2 Metropolitan Edison Co. General Public Utilities f=?'I Mr. William Zewe May 11 .sg. Station Shift Supervisor lj Metropolitan Edison Co. jEJ TMI Unit 2 General Public Utilities [C.' 51 :!- r~ Mr. Gary Miller May 11 Station Manager r.# TMI Unit 2 -...f;... Metropolitan Edison Co. 15l.- General Public, Utilities f..s _ p f.--- Mr. Frederick Sheimann May 11 Station Shif t Foreman 'E" TMI Unit 2 ~ Metropolitan Edison Co. ~ 1;- ~t-'f General Public Utilities t.l -~ ~ IE:.1 ?L. John McMillan May 15 IEiis5 Vice President jg_, Nuclear Power Generation Group };.;.. Babcock & Wilcox

t..:I Lynchburg, Virginia kl:; '~

T#s Mr. James Deddens May 15

[$ Manager, Projects Management Group i-.=2 E 25 Nuclear Power Generation Group ' W;.: Babcock & Wilcox Lynchburg, Virginia

== EEE~ --- y 5 g-- = . s_e L., 799 324}}