ML19246A354
| ML19246A354 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 05/02/1979 |
| From: | Alderman H Advisory Committee on Reactor Safeguards |
| To: | Advisory Committee on Reactor Safeguards |
| References | |
| ACRS-SM-0103, ACRS-SM-103, NUDOCS 7906180592 | |
| Download: ML19246A354 (20) | |
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UNITED STATES NUCLEAR REGULATORY COMMISSION g 1 7-
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WASHINGTON D. C. r0555 M.ay 2, 1979 ACRS t'.E:'_DEid IIICHLIGiiT OF 3rd HCARI!G GN THREE MILE ISLM;D U'JIT 2 BY THE SENATE SUE-CO"RITTEE ON NUCLEAR REGULATICt4 APRIL 30,1979 The list of witnesses is attached. In addition to the stated paople, all the I;RC Commissioners were in attendance.
1.
Senator Hart ocened the hearing. He stated that the discussions tocay will cover.
shutdown and modification of Babcock and Wilcox reactors a.
b.
actions taken to bring TMI-2 to shutdown on Friday discussion of March 30th - the evacuation, the bubble of c.
hydrogen and the disagreement regarding the means to eliminate it d.
why reccamendation to evacuate not heeded e.
how serious was T4I-2 accident f.
how close to a Class 9 accident should Class 9 accidents be considered in licensing process g.
h.
why didn't inspectors discover two closed valves
- i. the role played by B&W in the hours after the accident II.
Senator Simpson's opening remarks. Senator Simpson stated that one lesson learned from this accident is that the reactor operator response to emergency situations is less than adequate.
He stated that he will propose to the NRC:
operator response to emergency situations be stressed a.
b.
that criteria be prepared delineating enginee: ing backup plans be developed for energency engineering tesponse c.
d.
Ccmmission to prepare review program to see if less severe incidents are considered in sufficient detail to accelerate program to have resident inspector at each e.
reactor site.
f.
propose increase in civil penalties for violations reccmaend plant management be held accountable for plant g.
operations and licensing propose direct link between nuclear reactor control roca and h.
NRC, (a dedicated hard wired-telephone) and a designated individual to crmunicate with the NRC
- i. monitoring of plant conditions by t:RC
- j. plans for swif t response by NRC to plants with ccergencies 79061805n 228 159
proposal that licensing of reactors dependent state's emergency k.
plan
, 1.
impr.ed safety research as suggested by ACRS more work on generic safety questions m.
III, Har;1d Denton was the leadoff witness. He stated that the current status of SMI-2 was in natura) circulation.
Temperature is about 180 F, the steam generator has a delta T of about current iodine release is at very low levels.
The most current pressing problem is what modifications are neces-sary to isolate the water in the containment from the environment.
O.
Senator Hart khat is gained by shutting only one Oconee reactor at a time?
Why is Rancho Seco shut down immediately?
A.
Denton Oconce to provide an operator at each auxiliary feed water pump - this will provide a high degree of assurance of the pumps to start.
The valve lineup will be manually maintained so that each unit could supply other units. This resolution is satisfactory for the short term basis.
O.
Hart - What is short tenn?
A.
Denton - On the order of 2 months.
Hart - It took 5 days to shut reactors down for seismic Q.
criteria and 1 month to shut down S&W reactors - why?
Denton - it took longer to perceive risks at B&W plants.
A.
Hart - what convinced staff to go to lesser of shutdown O.
requirements for B&W plant?
Denton - The only change is that 2 units of Oconee not shut A.
down immediately.
Hart - to what extent did economics play in the situation?
O.
A.
Denton - none.
O.
Hart - Why stable shutdown (TMI-2) 5 days early?
Wanted to A.
Denton - r.ainly failut e of pressurizer instr uments.
go to natural circulation at time when experts are readily available and maximum amount of instrumentation available.
Q.
Hart - Describe condition of instrumentaion. Can fou operate without pressur izer level?
228 160
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Can calculate levels using makeup tank levels and outflow.
Another gage has been installed outside containment. A third
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method is using a Delta P level indication. The pr essur izer is kept solid.
O.
Hart - Did control room operators wear gas masks during the accident?
A.
Denton At one time iodine was suspected to be leaking from the steam generators - When it was confirmed that it was not, the masks were removed.
Senator S;mpson 0 Economics, energy considtratio,ns blackout conditions, did not entet into your consideration to shutdown B&W reactors?
A.
Denton - They were not primary considerations.
Q.
Why wern't B&W reactors shut down right after accident?
A.
Denton - my activities were involved with the TMI-2 situation.
The staff was studying the contribution of design in the TMI-2 accident. The initial concept involved operator effects.
Further study revealed that BLW reactors had many feed water transients.
Q.
The computer response showed the pressure valve (relief) open.
Is it true there was no way to verify this on the panel?
A.
Mattson - There were theroccuple indications that the va]ve was open.
In addition there were quench tank temperature and pressure indications.
Q.
Senator Simpson - regarding operator training actions to improve operator training - how long to canplete?
A.
Actions to be completed in about one month.
Senator Domenici 0 - Does NRC plan to implement hot line communi-cations with reactors?
A.
This is under active study.
Q.
Should NRC nonitor computer output remotely?
A.
Present setup requires licensee call NRC within one hour.
I&E has 24 hout service with professional standing by at ~ a telephone.
The concept of a hot line and remote computer readout is being investigated.
228 16i
2
. O.
Did NRC avail itself of DCE expertise, that is, National r,un, A.
NRC used DCE expertise.
Senator Hart 0 - The concept of remote monitoring and a nuclear "SMT" team - what are your thoughts on this?
A.
These are under consideration.
Q.
Describe a Class 9 accident.
A.
These are accidents that are not in the scope of review--
accidents beyond the design basis.
Hart Remark - This sounds like a Catch 22 situation.
Q.
Will this accident alter the licensing procucs?
A.
Yes - changes will be made.
Q.
How would you define the TMI-2 accident? Would you call it a Class 9 accident?
A.
The initiating basis was a design basis accident. The result-ing accident was a Class 9 accident.
Q.
How close did core come to melting down?
A.
Tbo early to answer question. The largest risk was curing the first day. The fuel reached very high temperatures.
Q.
My understanding is that the core was fully uncovered for one hour - is this true?
A.
Yes.
(Answer included cycles of partial covering).
Q.
Why did it take Commission as long as it did to measure extent of damage?
A.
Full extent of damage not indicated until coo?. ant sample analyced.
Q.
If all this infornation had been available earlier, would you have recommended evacuation?
A.
Work was on a day-by-day basis. Evacuation was recommended en Etiday morning - report of noble gas release. Concern was breaking of containment.
Later report was that offsite doce release was much lower and releases not from breaking of containment.
228 162 s
I Senator Simpson 0 - Have you verified dif ference in radiation and lower containment?
readings between uppet Traverse radiation rcadings were taken outside containment.
The lower I
Back calculations correlated with interior reading
. A.
V6uld you say that this (high radiation) will be a deterent to Q.
cleanup and testoration'.-
A.
Difficult, but not impossible.
hhen did you know about the deterioration of the zirconium Q.
clad?
It Somewhere between Wednesday morning and Thursday night.
became apparent from the thennoccuple data and the trending of A.
The hydrogen explosion.in the containment was addi-tional evidence. Another indicator was analysis of the primary the data.
coolant.
Are simulators effective training methods?
Q.
B&W is adding abnormal flot as effective as they should be.
A.
situations in simulator training.
Should plant managers be licensed?
Q.
There may be Chairman Hendrie_ - This is difficult cuestion.
A.
other ways to handle this.
Hart raised concern about uranium falling to bottom of contain-ment and becoming critical.
How long will uranium remain in plant.?
Q.
Some uranium Mattsor. - I believe core is relatively stable. Calculations of bounding A.
may be suspended by the fluid flow.
conditions indicate no safety concern.
Can you rely on your present instruments.?
Q.
The instr uments have been calibrated. The present instrumenta A.
should continue to per form well.
Can you detect loose uranium at the bottom of the core?
Q.
Thete is no mechanism for additional uranium to settle to A.
bottom of cote.
228 16'
km.
- Senator Hart i
Q.
Senator Hart asked about the threat of Met Ed to remove all 'n41-2 personnel
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A.
Denton - This didn't happen in my presence. The understanding is for NRC to approve all procedures in advance. There were confrontations over various issues. Cnly plant emplcyees actually operate plant.
Q.
Was there sny doubt that utility would do what you require?
A.
Absolutely not.
Q.
hhat technical basis used to advice Governor the basis of a meltdown, about 1%?
A.
Don't recall 1% figure. The concerns were with hydrogen bubble and the possible use of R.H.R. to cool down.
Senator Moynihan Q.
Tt.e 1 in 100 probability of a me'.tdown seems high.
The mitigating considerations were that it would take consider-A.
able time to initiate event and the probability of loosing cooling was very low.
Senator Simpson_
Q.
To what extent do you observe licensee activities.?
A.
Davis, I&E - Mainly we inspect hardware to verify 0.A.
There are no large samples. We are moving into the resident inspec-tor program.
Q.
There were inspections March 23 and March 26.
How many inspectors inspect control room?
A.
One inspector involved. Ot servation not item of non-compliance.
Were valves closed and switches tagged during inspection?
Q.
A.
This is under investigation.
Q.
A photo in a magazine shows tagged switches - couldn't plant supervision and inspectors detect this?
A.
Dua't have details - this is under investigation.
Q.
hhy did operator withhold information re hydrogen explosion?
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A.
Don' t know answer.
0 Moynihan-Questioned conpetance of Met. Ed. engir ering staff.
A.
Not as extensive as many other utilities.
Q.
Simeson-What arrangements have been made to cooperate with Presidential Commission?
A.
Hendrie - We will cooperate in everyway.
IV.
Babcock & Wilcox
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Louis Favret -Executive Vice President John H. MacMillan, Vice President - Nuclear Power The prepared testimony is attached.
Favret had introductory remarks and then presented MacMillan to give the main presentation.
John MacMillan presented the significant event of the accident.
a.
closed auxilary feedwater valves b.
pressure relief salve opened properly, but didn't close properly the high pressure injection system prematurely closed by c.
operatur d.
had high pressure injection been allowed to continue, no damage to fuel would have occurred.
, Q.
ytrt - when was high pressure injection terminated?
A.
In first few minutes of accident.
Mr. MacMillan continued his presentation.
e.
The indicated pressurizer level not significantly in error f.
the shutting of all reactor coolant pumps resulted in uncover-ing of the core, g.
B&W equipment with the exception of the relief valve performed as designed.
Regarding the shutdown of B&W reactors, Mr. MacMillan said he ptefer red the decision rather than full forced shutdcon. Ec believes the reactor plants could continue to operate without hazard to public.
Q.
Hart -Haw many subcontractors for primary system?
A.
Could to as many as 50.
228 165 w
s
. Q.
Could there be as many as 100?
. A.
There could be that many main suppliers.
Q.
Dr. Lipinski stated that status of instrumentation should be displayed on main control panel.
Mr. Michelson stated that his comments were not responded to.
A.
tbt familiar with Lipinski's comments. B&W responded to Michelson and were told that Michelson had no further comments.
Q.
Hart - orally?
Long pause -
A.
Taylor B&W initial response to Michelson.
Feb 1979 Michelson responded that he required further clarification.
It appeared to B&W that very minor points needed clarification.
Q.
Hart - is it true that the pressurizer relief valve actuated 150 times?
Yes, in over 38 reactor years operation it actuated over 150 A.
times.
Q.
How do you account for the 150 times?
A.
The design of the system initiates reactor rollback during a turbine trip. This helps the reactor stay on line. During the rollback, the relief valve opens.
Q.
Hart - If you had been in operator's shoes, would you have done what he did?
A.
This is a highly speculative question Information from data center indicated leak in coolant system.
Q.
Simpson - Which of the events would you designate as operator error and which equipent failure?
Equipment failure - the relief valve and the transfer to A.
the auxiliary building. The others as operatos errot.
Q.
Was the operator getting clear and unambiguous information as part of operator training?
Operator ex@ sed to large nu-ber of equipent malfunctions A.
during training - one is loss of coolant malfunction.
level was valid Cperator has several indications pressur izet reading.
228 166 s
_9_
Systen pressure indication - As the pressure decreased, quench tank indi.cator and containment pressure indicator. Evidence that opening in reactor coolant system existed.
O.
Hart - Why technical soecifice. ions require valve closure during testing of auxiliary feed water system?
A.
Bis is not a B&W system, this is supplied by A-E.
Q.
Do you believe that licensing training should be reassessed?
A.
Yes.
Q.
Regarding the hydrogen bubble, why was this not anticipated, where did the bubble go?
A.
We hydrogen was generated by the oxidation of the circonium cladding. Hydrogen is soluble in the ca.lant. Part was released in the vapar phase of pressur!zer and part in the vapor phase of letdown tank.
RECESS Simpson - Does B&N have any further co. rent?
T MacMillan - B&W is conducting an analysis far beyoa3 that required by the NRC.
V.
W. Wilson Goude - Pennsylvania Public Utility Commission Mr. Goude stated 1.
safety regulatien of nuclear reactors is a federal function 2.
if the costs of the accident are passed on to the consumer, the bills will be increased 30-40%
3.
Mr. Goude stated that new legislation would be required to spread costs across all nuclear utilities Attached are copies of the prepared testimony and a newspaper clipping describing this hearing.
A Herman Alderman.
Reactor Operating Experiece Engineer cc: Technical Staff 228 167
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IRild D@ Ik'llil',l DANla FOR RELEASE:
CONTACT:
April 30, 1979 Kathy Durhkin 9:00 s m.
224-5852 OPDlING STATDtENT BY SENATCR CA3Y IGRT CHAIRMAN, SUBCC:t'iITTEE ON NUCLEAR REGULATION
- day's hearing is the third in the preliminary phase of our l
special investigation and study of the accident at the Three Mile Island nucicar plant.
We will review today two very important developments:
--The agreement reached la st Friday between the Nuclear Regu' a tc:
Commisseon and af fected utilitics regarding shutdcwn and modification of all 1sbcock and Wilecx reacters, and
--tlc action taken at the Three Mile Island site, also la st Frid' to bring the damaged reactor dcwn to a "stabl.a shutdown" cond ', tion nearly a week ahead oi schedule.
We also wish to explore today the Commiss. ion's decision-making process and a critica l element in the sequence of events during the height of the crisis.
On the morning of Friday, March JO, the top technical staf f of the NFC was recommending to both the CO mission and the Pennsylvania State officials t?
there be an immediate evacuation to a distance of fi e miles trot. the plant.
That recommendation was not followed.
As I understand it, the staf f was acting on the basis of some very disturbing information:
First, the bubble trapped in the top of t.he reacter vessel was determined to !.
hydrogen and was presumed at the time to be potentia l explowlve.
Second, there was strong disagreement over how tm.et rid of the bubble.
The Met; opoli tan Edison of ficials wanted to depressurize the reactor; the "RC stra f vas concerned that such an action would enlarge the bubble, b sck the llow of coolart to the core and precipitate a meltdown.
F ina lly, it was also determined there was only a one-hwur espacit left in.he ga s-nolding oks of the auxiliary building, which meant tha t radicactive ga s mig t.t have to be released into the a tmosphere, i
I am advised by the 'ubcommittee staf f that this is a fair summary of the situation i ha t prompted the senior technical staff of the NRC to reccmmcrd evac',0 tion.
We sculd like to question the NRC staf f today about tha t reccmmc.T tion to evacuate, and wc will also question Chairman Hendrie and the other Commissior members who are present about why the reccmmendation was not heeded.
It is im por ta n t for us to understand the fact-finding and decisier making process as it worked--or did not work--so tha t if bad precedent:
were established, we are now in a position to brcsk them and be better prepared to d al with such cmergencies in the future.
I j
We alao will explore today just how serious the accident at ihree M11e 'cland was.
Specifically, we want to know how close it can to becoming a catastrophic, so-called 'Cla s s 9 acc ident"--one involvto i
a meltdown of the nuclear fuel, a broach,of t he centa i nment buildinq, and a ra pid spreadofradioactivg[ gager [g
,30 1,cgto the surrounding comnun-4*iaa
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This is an im por ta n t question because present procedures fc1 designing, building and licensing reactors do not take into account the possibility of a Class 9 accident.
Such an accident ha s been deemed so improbable as to be virtually ir..possible.
Does this accident confirm or dispute this assumption? This is an issue which should be raised and aired fully.
We also want to determine why, during NRC inspections of the Three Mile Island plant during the days immediately prior to the accident, the inspectors failed to discover the two shu t valves which were so critical in causing the accident.
Finally, we will be aksing the NRC witnesses to connent on proposals which this subecmmittee is considering in connection with the fiscal year 1990 ruthorization bill, and in tho' form of separate legislation, to strengthen NRC's capabilitics for preventing and dealing with future cmergencies.
In addition to the NRC* witnesses, we will also be hearing from top cxecutives of the Babcock and Wilecx Company and from W. Wilson Goode, Chairman of the Pennsylvania Public Utilitics Commission.
' We wish to explore with the Babcock and Wilcox cxecutives the operating record of their pressurized water reactor, as it compares with that of such reactors built by other manufacturers.
We will also a sk about the significance of the agreement between the NRC and the utilitics on shutting down B&W reactors; the inter-action among design def ects, mechanical failures and human errors in the operation of nuclear reactors; and finally, the role played by B&W during the first hours and days af ter the accident at Three Mile Island.
With Chairman Goode, we wish to explore the important issues of who will pay the cost and assume the risk of the accident at I
Three Mile Island--the investors or the customers of the utility.
The Pennsylvania Public Utilitics Commission is examining the economic fallout of the accident now.
We will want to discuss how its inquiry is precceding and ways in which there can be cooperation and coordination between its inquiry and ours.
If the Three Mile Island nuclear accident has taught us anything, it is the need to face squarely problems and issue from which the public has been generally shicided until now.
Nuclear power has a future only in the people have confidence in it.
That means there must be a full understanding of the benefits and the risks.
Health and saf ety questions and economic-2mpact issues must be fully explored. That is what this Subcommittee's hearings and special investigation are intended to achieve.
I
-end-228 169
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COMMITTEE ON ENVIRONMENT AND PUBLIC WORKS,
SUBCC:011TTEE ON NUCLEAR REGULATION HEARING ON
'"HREE MILE ISLAND NUCLEAR POWER PLANT ACCIDENT r
APRIL 30, 1979 9.00 a.m.
Room 4200 Dirksen Senate Office Building WITNESS LIST 1.
Nuclear Regulatory Commission Panel Harold Denton Director, Office of Nuclear Reactor Regulation accompanied by:
Edson D.
Case Deputy Director, Office of Nuclear Reactor Regulation Roger J. Mattson Director, Division of Systems Safety John G.
Davis Acting Director Office of Inspection and Enforcement Chairman Joseph M.
Hendrie and Members of Nuclear Regulatory Commission 2.
Babcock and Wilcox Panel Louis Favret Executive Vice President Power Generation Group John H.
MacMillan Vice President of Nuclear Power 3.
W.
Wilson Goode Chairman of the Pennsylvania Public Utilities Ccmmission 228 170
r
SUMMARY
STATEMENT OF THE BABCOCK & WILCOX COMPANY BEFORE THE SUBCOMMITTEE ON NUCLEAR REGULATION OF THE SENATE COMMITTEE ON ENVIRONMENT AND PUBLIC WORKS APRIL 30, 1979 John H. MacMillan Vice President Nuclear Power Generation Division The Babcock & Wilcox Company Lynchburg, Virginia 228 171
Good morning, my name is John H.
MacMillan.
As Mr. Favreb mentioneE, I am Vice President of the Nuclear Power Generation Division of The Babcock & Wilcox Company.
My remarks today are highlights of my written statement submitted to the Subcommittee.
As a way of introduction and background for our purposes today, the key participants in a nuclear plant are the utility, the NRC, the engineering firm, and manufacturers of equipment such as B&W.
As a general rule, the responsibilities of. nuclear steam system manufacturer are 1) to design and manufacture and/or provide the components of the primary system and reactor safety systems; 2) to provide interface information to the engineering firm for the balance of plant; and 3) to provide licensing and startup support to the utility.
The general responsibilities or the engineering firm are
- 1) to coordinate the design of the entire plant 2) to provide the containment design and design of the balance of plant (that part of the plant not included in the nuclear steam system),
and 3) to integrate the various participants' workscores into the overall plant design.
228 172 The NRC 1) reviews the plant designs and approves them;
- 2) issue"s construction permits, as required by the Atomic Energy Act, prior to commencement of any significant construction;
- 3) issues an operating license prior to fuel loading following its approval of final design; 4) establishes criteria and require-ments for licensing of operators; and 5) monitors operating plants.
With this background, it is apprcpriate to move into a discussion of the incident at Three Mile Island.
To provide a context for these remarks, the six significant factors identified by the NRC shall be used as a framework.
Following discussion of the significant factors, B&W's near and long term planned actions in response to the incident will be set forth.
First, after the loss of feedwater occurred, two closed isolation valves prevented auxiliary feedwater from reaching the steam generators for a period in excess of eight minutes.
This eliminated the capability of the steam generator to remove heat from the reactor coolant system, and resulted in a corresponding increase in reactor coolant system temperature and pressure, and diminished the ability of the plant to promptly stabilize reactor coolant system temperature and pressure as designed.
228 173
.228 i,
Second, as a result of the initial reactor coolant system pressure and temperature increase, the pilot-operated pressuriner.
relief valve (located at the top of the pressuriner) opened as designed, but did not reseat properly, thus allowing reactor coolant system pressure to continue decreasing.
After approximately 2h hours, the operator recognized the data from plant instrumentation which indicated that the valve was open, and closed the block valve in the relief valve discharge line, thus preventing any further loss of primary coolant.
Third, the high pressure injection system, which had automatically actuated as designed on low reactor coolant system pressure, was prematurely terminated by the operator even though there were simultaneous indications of an opening in the reactor coolant system pressure bounc.ary, such as increasing quench tank pressure, decreasing reactor coolant system pressure and increasing reactor containment prdssure.
This led to a diminished capability to cool the reactor core as primary ccolant inventory diminished.
Fourth, the containment isolated in accordance with the licensed design.
However, this allowed the transfer of radioacrive water from the reactor building sump to the auxiliary building, from which subsequent radiation releases occurred.
Fifth, high pressure injection was evidently manually operated based on high pressuriner level indication.
We have conducted reviews of data from Three Mile Island and 228 174 performed analyses that lead us to conclude that the indicated pressur4rer level was not significantly in error.
We believe that the pressurizer was essentially full during a long period of this' transient, but a portion of the reactor coolant system was void due to the decrease in system pressure.
This conclusion has been supported by an independent NRC study.
Consequently, operation of high pressure injection flow should not have been based on the single parameter of pressurizer level.
Sixth, in addition to two reactor coolant pumps hav.ng been shut off at 73 minutes, the remaining two reactor coolant pumps were shut off at 100 minutes after the initiation of the incident.
Although shutting off one reactor coolant pmnp in each loop in response to indications of low coolant flow nay be advisable, shutting off all pumps under the circumstances then present is believed to have caused an uncovering of the core and a degradation in core cooling capability.
Ultimately, at about thirteen hours after initiation of the transient, the reactor coolant system was repressurized, and at about 15 hours1.736111e-4 days <br />0.00417 hours <br />2.480159e-5 weeks <br />5.7075e-6 months <br /> the reactor coolant pumps were restarted.
Our analysis of the foregoing factors and the need credibly to build public confidence in the reliability of nuclear power has led us to conclude that we should take further measures to assure and enhance continued safe operation of B&W-cupplied reactors.
228 175 For actions that B&W has already taken, I would refer you to a full e9.planation of them in my written statement.
With respect to near term actions, B&W recognizes that additional measures should be taken so that operators are better able to manage transients.
Th? following summarines the actions B&W has currently underway or will be commencing soon to further enhance the safety of B&W units.
1.
On Monday, April 9, B&W began conducting training for operating and management personnel on the events involved in the TMI-2 incident.
The training consists of the following:
Discussion of the TMI-2 transient from the information e
available to B&W.
Demonstration 'of the incident on the B&W simulator.
Training sess. ion of the simulator having students recover the plant from a depressurization event which involves the formation of steam voids in the reactor coolant system outside the pressurizer.
Six operators are included in each training session.
The training sessions last one day.
All utilities with B&W systems presently have this training in progress or scheduled for personnel.
2.
The B&W supplied equipment in both the primary and secondary plant, with the exception of the pilot-operated pressuriner relief valve, performed as designed.
However, in view of the events at TMI-2, design improvements are being 228 176 considered to further enhance the ability of plant operators to contfoi nuclear power plants during transients.
In the near term we expect to recommend design improvements which do not affect other systems within the plant or require extensive analysis to improve operator performance during transients similar to TMI-2.
In this category are such things More positive indication of pilot-operated relief valve as:
position and instrumentation which will indicate to the operator whether the reactor coolant is approaching the saturated condition.
We anticipate that recommendations of this type will be made within six weeks.
3.
A special B&W task force has been appointed to advise of other implications for plant design as a result of the TMI-2 incident.
This task force is comprised of a diverse group of technical personnel with a charter to Review technical aspects of the TMI-2 incident; Develop recommendations for equipment improvements, operator interface, recovery requirements and incident support; Assess impact of the TMI-2 incident and potential resulting changes in regulatory requirements on Nuclear Power Generation Division technical activities.
Beyond the immediate and near-term actions, longer-term actions will be undertaken.
228 177 B&W intends to undertake a review of those anticipated transients which result in the opening of the pilot-operated relief valve to confirm that an open pilot-operated relief valve in conjunction with anticipated transients is adequately covered by exist.ing safety analyses.
In parallel with these anticipated transient reviews, B&W intends to review its operator training programs and will make changes as appropriate.
Beyond those actions fo.- design modifications under our near-term efforts, B&W will be exaqining other actions, but with the understanding that each must be carefully evaluated with respect to any impact on other design requirements.
In conclusion, Babcock & Wilcox appreciates the seriousness of the incident at Three Mile Island and is commit ed to take responsive actions to incorporate the lessons learned.
B&W is continuing to maintain an "around-the-clock" communications center at our Lynchburg facilities and an on-site team -- which I headed until recently -- who have at their disposal all of the resources of B&W to support the efforts of Metropolitan Edison and the NRC.
B&W as well as all others are gratified that the situation at TMI is under control and progressing towards cold shutdown.
B&W will continue to give top priority to support the efforts at the site and to implement the actions by the NRC, Met Ed and all other utilities towards prevention of any further occurrences in the nuclear power generation industry.
Babcock & Wilcox appreciates the opportunity to participate in the Subcommittee's investigation and review of the TMI incident.
228 178