ML20206E095
| ML20206E095 | |
| Person / Time | |
|---|---|
| Site: | Three Mile Island, 05000000 |
| Issue date: | 05/26/1981 |
| From: | Cale Young AFFILIATION NOT ASSIGNED |
| To: | |
| Shared Package | |
| ML20206D924 | List: |
| References | |
| NUDOCS 8811170396 | |
| Download: ML20206E095 (84) | |
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L AN ANALYSIS OF THE THREE MILE ISLAND ACCIDENT
{, A Study by Charles foung May 26, 1981
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INTRODUCTION
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The Tnree Mile Island Unit 2 Nuclear Plant was severely damaged during an accident on March 28, 1979. The plant _is out of commission and will not generate electricity for an
[ indeterminable number of years. The plant must be decontami-nated at a cost estimated at one billion dollars. The estimated
- t. cust cv temi.vte cne plant to an operationaa. condition exceeds t S260 million. Three Mi'.e Islana Unit 1 is not operating because of the Unit 2 accident.
[ Human error caused tne accident:
An error by the Primary Plant Operator at 0403, March 28, 1979.
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Errors by others attempting to cope with a problem caused by the Primary Plant Operator. l
[ Errors are identified in the Study. Proper performance is cited. Causes of errors are examined and corrective action is !
developed.
( A Summary of the Study follows. Errors are summarized. The Problem at Three Mile Island is identified and corrective action is summarized.
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SUMMARY
ERRORS, THE PROBLEM AT THREE MILE ISLAND, AND CORRECTIVE ACTION Primary Plant Operator's Error High Pressure Injection System and Pressurizer Level Station Manager's First Errors i l
Station Manager's Third Error
( l Vice President Changes Operations l The Problem at Three Mile Island Managing Three Mile Island Metropolitan Edison Corporate Management Responsibility for Three Mile Island
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Metropolitan Edison Corporate Officials and the Accident on March 28, 1979
( A Corrective Action Program for Three Mile Island
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( ERRORS, THE PROBLEM AT THREE MILE ISLAND, AND CORRECTIVE ACTION h
Primary Plant Operator's Error l The Primary Plant Operator raade the error 'which caused tha Three Mile Island accident on Mar'h 28, 1979 - he shut down the High Pressure Injection System.
The Hign Pressure Injection System is a nuclear plant Safety System. An Emergency Safeguards Signal initiated by low pres-
[ sure in the Reactor Coolant System started the High Pressure t Injection System at 0402. Low pressure in the reactor coolant system is abnormal in a nuclear plant.
f There had been problems with the High Pressure Injection System at Three Mile Island. The System malfunctioned and pumped a foreign chemical into the reactor coolant system. The
.( system pumped a foreign chemical into the reactor coolant system ,
twice when an Emergency Safeguards Signal started the System following a reactor scram. Removing the chemical put the Unit 2 nuclear plant out of commission.
[
After these problems, Three Mile Island Operators were instructed to shut the High Pressure Injection System down promptly if the System started following a reactor scram.
Operators were instructed to shut the System down to shorten Unit down time by preventing the foreign chemical from being
( pumped into the reactor coolant system.
" One year before the March 1979 accident, on March 29, 1978, the Primary Plant Operator shut cown the High Pressure Injection l System. An Emergency Safeguard Signal initiated by low pressure in the reactor coolant system following a reactor scram started the High Pressure Injection System. The Operator shut down the High Pressure Injection System on March 29, 1978 to minimize reactor plant down time by preventing the foreign chemical from being pumped into the reactor coolant system.
[
ne Primary Plant Operator was following instructions when he slut down tne Eigh Pressure Injection System at 0403 March 28, l979. He was also handling the High Pressure Injection
{ System as the System had been handled before.
7 The Primary Plant Operator's purpose in shutting down tne
( Hi.gh Pressure Injection System on March 28, 1979, was to rinimize reactor plant down time.
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( The Shif t Supervisor was in charge at Three Mile Island Unit 2 wnen the scram occurred at 0400. Tne scram shut down the
[ reactor plant interrupting thc generation of electricity. The L Shift Supervisor's primary effort during the first hour of the Three Milo Island accident on March 28, 1979 was to discharge his responsioility to get the plant back og line generating
(- electricity. He left the Unit 2 control room at 0415 to work on the condensate system. The condensate system is required to be operating for the Unit 2 reactor plant to generate electricity.
(, He returned to the Unit 2 Control Room at 0500 having rectified '
the problem in the condensate system which caused the reactor scram.
The High Pressure Injection System was pumping coolant into the reactor coolant system when the Operator shut the System down. Coolant was needed cecause coolant w:s being lost through
( the stuck open relief valve. As coolant was lost from the reactor coolant system, pressure decreased and steam formed along the fuel rods causing the rods to overheat. Reactor
( coolant pumps were shuc down and coolant was no longer circulated through the reactor core to remove decay heat. The reactor core was therefore damaged.
If the High Pressure Injection System had continued pumping coolant into the reactor coolant system at 0403, system pressure would have increased. With increased system pressure and the
( capacity of the reactor coolant system to remove decay heet restored, reactor coolant pumps would have continued to circulate coolant through the reactor core. The reactor
( coolant system would have removed decay heat as desianed and the reactor core would not have been damaged.
Metropolitan Edison's Technical Specifications for Three
[ Mile Island Unit 2, are part of the Plant Operating License.
The Operating License was issued to Metropolitan Edison by the Nuclear Regulatory Commissio' by authority of Congress.
Technical Specifications identify design conditions for Unit 2 safety systems and stipulate that safety systems shall operate
( under design conditions.
Three Mile Island Unit 2 Technical Specifications require tne High Pressure Injection System to operate as designed to
[ pump coolant into the reaccor coolant sistem as long as reactor coolant pressure is below the System's actuation setpoint.
( Technical Specifications also stipulate t.at Three Mile Island Unit 2 is to be operated in accordance with Station Procedures developed from the Tecnnical Specifications. Three
( Mile Island Unit 2 Station Procedure 2202-1.3 requires the High Pressure Injection System to operate as designed when reactor coolant system pressure is below 1640 psig.
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[ When the Primary Plant Operator shut down the High Pressure Injection System at 0403, reactor coolanc system pressure was below 1640 psig.
The Primary Plant Operator should have verified that the High Pressure Injection System was operating at 0403 as required
[ by Station Procedure 2202-1.3. Instead ne shut the System down.
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[ HIGH PRESSURE INJECTION SYSTEM AND PRESSURIZEB LEVEL The High Pressure Injection Svstem was started by low reactor coolant system pressure at 0402. The Primary Plant operator began to shut down the High Pressure Injection System by turning off the Emergency Safeguards Signal at 0403. Reactor
( coolant system pressure was below the operating range, decreas- 1 ing. The pressurizer was less than two-thirds full. l l
[ The reactor coolant system was not going solid and system conditions did not indicate that the reacter coolant system was going solid when the Operator shut down the High Pressure Injection System.
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[ Station Manager's First Errors The Station Manager accepted conditions at Three Mile Island Unit 2 at 0515.
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The Station Manager called the Station at 0515 and talked to the Superintendent Technical Support for about 20 minutes. He
[ was told that reactor coolant system pressure was abnormally low and that an Operator had shut down the High Pressure Injection System.
The Station Manager became disturbed about plant conditions but he did nothing to change plant conditions. He did not
[ change the way Operators were operating the plant.
The Station Manager accepted an Operator's shutting down the Hign Pressure Injection Safety System following a reactor scra'
( on March 29, 1978. !!e accepted an Operator's operating the System the same way on March 28, 1979.
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l The Stati 7n Manager decided to call the Vice President, Generation, Metropolitan Edison during the 0515 call to the
( Station. He caAled the Vice President at 0600. The Superin-t tendent Technical t'pport also participated in this call which lasted about 35 mis 'es.
[ The status of the plant was discussed. Participants knew that the condition of Three Mile Island Unit 2 was abnormal.
The Superintendent Technical Support told them that reactor
( coolant pumps had been stopped. They knew that forced l recirculation of coolant through the reactor core had to be l reestablished.
The Station Manager again accepted cond3[ons at Three Mile Island Unit 2. He made no change in the way Three Mile Island )
Unit 2 was being operated as a result of the 0600 call. l l
No change was made because operations at Three Mile Island were not required to conform to a standard. Operators operated as they thought best. Operations did not always conform to
( design because operations were not required to conform to Plant Technical Specifications, e
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L There was no urgency to resolve the problem at Three Mile Island by the Station Manager or the Superintendent Technical
, Support during their 2 telephone calls. There was no urgency
[ because there was a break in the line of responsibility between the Station Manager and his Station organization.
' The Superintendent Technical Support was not responsible for plant operations and not accountable to anyone for the outcome of events at Three Mile Island. He was not expected to exercise r authority over the Shift Supervisor or the Plant Operators. Yet L he represented the Station in the telephone calls with the Station Superintendent.
( The Shift Supervisor was in charge at Three Mile Island and he remained in charge after the Superintendent Technical Support arrived at the Station. The Shift Superintendent did not
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participate in the telepho*e calls with the Station Manager.
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The Superintendent Technical Support accepted conditions at Three Mile Island Unit 2, when he arrived in the Control Room about 0450. '
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The Superintendent Technical Support recognized an abnormal r situation when he arrived. Reactor coolant system pressure was i abnormally low and the High Pressure Injection System had been shut down. The Shift Supervisor, who was in charge of Three Mile Island was not in the Control Room between 0415 and 0500.
( The Superintendent Technical Support accepted plant condi-tions at 0450. He did nothing to change conditions.
The High Pressure Injection System had been shut down before, therefore he felt no responsibility to change this method of handling the System.
He was not responsible for plant operations as "duty section head" or as Superintendent Technical Support.
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He was therefore under no obligation to ensure that proper actions were taken at 0450.
The Superintendent Technical Support, recognized an abnormal situation at 0450, and he called additional technical and opera-tions personnel to the Station.
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The Superintendent Technical Support accepted the Shift Supervisor's decision to shut down the reactor coolant pumps and rely on natural circulation to cool the reactor core. He
( concurred with this decision about 0514, even though reactor coolant system pressure and temperature were outside the limit.s of the Heat Up/ Cool Down Curve.
The Superintendent Technical Support was busy when the Shift Supervisor returned to the Control Room at 0500. He was dir-( ecting that technical and operations personnel be called to the Station. More than 10 were called.
( He talked on the telephone with the Station Superintendent from 0515 to 0535. He participated in a call with the Vice president, Generation, Metropolitan Edison and the Station Manager at 0600.
He gave assignments to personnel. He directed the Station Chemistry / Health Physics Supervisor to make preparations for a
[ reactor building entry. He started a log of events, making entries himself.
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( The Superintendent Technical Support was not responsible for plant operations. He was not expected to e.:erci.se authority
[ over the Shift Supervisor. He was under no obligation to take i time to ensure that the Shift Supervisor made proper decisions.
k The Unit 2 Superintendent also accepted conditions at Three
[ Mile Island Unit 2. He accepted conditions at about 0545 when '
he was briefed in the Control Room.
The Unit 2 Superintendent had been called to the Station
{ because the 0400 scram was abnormal. When he was briefed, reactor coolant system pressure was abnormally low and the High Pressure Injection System was off.
The Station Manager had accepted this method of handling the High Pressure Injection System so the Unit 2 Superintendent was under no obligation to change what the Operator had done.
Reactor coolant purapc were stopped at 0541, just before the Unit 2 Superintendent arrived.
{ l Operators were operating reactor plant systems in different ways attempting to overcome problems in the plant. Operators
( made the core flood system inoperable at 0600. Between 0713 and 1732, Operators frequently opened the block valve and electro-magnetic relief valve. Twice an Operator shut down the High
( Pressure Injection System af ter the System was started by an Emergency Safeguards Signal. Once the Operator did not start the High Pressure Injection System when the System should have started.
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These actions by the Operators, resulted in the Three Mile Island Unit 2 reactor plant being operated contrary to design.
The Unit 2 Superintendent and the other Three Mile Island Managers accepted these actions by the Three Mile Island
( Operators.
[ Station Manager's Third Error Tne Station Manager accepted the mode of operating Three
[ Mile Island Unit 2 which had prevailed since 0400 after his arrival in the Control Room at 0705. He had been called at home at 0650 and told that fuel failure had occurred.
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( The Station Manager knew that conditions at Three Mile Island were abnormal and he was disturbed. He knew there was no
[ circulation of coolant through the reactor core and that forced L circulation had to be reestablished. He knew fuel failures had occurred. He had learned these things in 4 tel<. phone calls with the Station between 0401 and 0700.
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After arriving at the Station at 0705, the Station Manager 1s.aumed rescnsibility for Three Mile Island Unit 2. He made no
( cnanges in the way the plara was being operated, however.
Operators continue 3 to operate reactor plant systems as they
[ had been operating since 0400. Operators continued to operate l systems in different ways as they thought best to overcome problems in the reactor plant. This mode of operating Three Mile Island Unit 2 continued until 1732.
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Operators continued to operate Three Mile Island Unit 2 as they through best because this was the way they always operated
( Three Mile Island. Operators did not follow rules in operating Three Mile Island when they had a way of operating which they thought was proper under the circumstances.
The Station Manager required no change in the way Operators were operating Three Mile Island Unit 2 at 0705 because he had permitted this manner of operating in the past. He did not
( require that orders regarding operation of the plant be followed because he did not have authoritative orders to give. He did not have authoritative orders to give because he did not require
[ tnat Three Mile Island be operated in accordance with the plant's Technical Specifications, f
The Unit 2 Superintendent also continued the mode of
' operating Tnree Mile Island Unit 2 whicn had prevailed since 0400. He continued this mode of operating even though fuel failures had occurred.
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The Unit 2 Superintendent was assigned responsibility for compliance with Procedures by the Station Superintendent at 0715.
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Operators opened the block valve and electromagnetic relief r valve at 0713 and frequently thereafter until 1732; shutdown the i High Pressure Injection System at 0817 and 1351; and did not start tne System at 0819. These actions, contrary to Station Procedures were accepted by tne Unit 2 Superintendent. Opera-( ,
tors were operating ystems as they tnought best to overcome problems in the plant.
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The Station Manager accepted Operators operating Th;.ee Mile Island in a way they thought best. The Unit 2 Superintendent was under no obligation to change this mode of operating.
The Unit 1 Operations Supervisor also continued the mode of operating Three Mile Island Unit 2 which had prevailed since 0400. He continued this mode of operating even though fuel
( failures had occurred.
J T The Unit 1 Operations Supervisor was assigned responsibility
( for plant operations directing the Shift Supervisor, by the Station Manger.
( Operators opened the block valve and electromagnetic relief valve together and did not operate the High Pressure Injection System as required. These actions by Operators occurred after
[' the Unit 1 Operations Supervisor officially assumed responsibil-ity for plant operations. These actions by Operators were con-trary to design and contrary to Station Procedures, The Unit 1 Operations Supervisor continued the mode of operating Three Mile Island Unit 2 which had prevailed since 0400 because he nad been directly involved in operating since
( 0600. Having been directly involved in operating since 0600, he did not review the way the plant was being operated when offi-cially assigned responsibility for operations at 0715.
b Th Unit 1 Operations Supervisor and the Plant Operators continued to operate Three Mile Island Unit 2 as they thought best to overcome problems until about 1732.
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( Vice President Changes _ Operations The Vice President, Generation, Metropolitan Edison changed
( the mode of operating Three Mile Island Unit 2 sometime after 1630. He directed that Unit 2 be repressurized rather than operated as determined oy the Operators.
The block valve for the electromagnetic relief valve was shut at 1732. Two High Pressure Injection pumps pumped coolant into the reactor coclant system raising pressure to 2300 psig.
( Reactor coolant pump 1A was started and run.
The reactor coolant system was operating as cosigned to remove deay heat from the reactor coce.
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Stable plant conditions had finally been reached.
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L The Problem at Three Mile Island E The Three Mile Island Unit 2 Primary Plant Operator shut
( down a nuclear plant safety system at 0403, March 28, 1979. The Operator thought that shutting down the safety system would
- enable him to return the reactor plant to service promptly. The L safety system, the High Pressure Injection System, had caused reactor plant down time twice by pumping a foreign chemical into the reactor coolant system.
The High Pressure Injection System was pumping coolant into the reactor coolant system when shut down. If the High Pressure Injection System had added coolant to the reactor coolant system L as designed at 0403, March 28, 1979, reactor coolant pumps could have continued to circulate coolant through the reactor core to remove decay heat. Damage to the reactor core would have been l
( prevented. Shutting down the High Pressure Injection System was {
contrary to design.
{ Operators were operating Three Mile Island Unit 2 contrary to design befor the accident. The electromagnetic relief valve j was snowing ope and the reactor coolant system was leaking. I Operators snould have closed the block valve to isolate the electromagnetic relief valve and stop the reactor coolant system l leak. Instead, Operators operated three systems abnormally. l
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The Station Manager accepted Operators' operating Three Mile Island Unit 2 with a relief valve showing open, the reactor
(- coolant system leaking, and three systems operating abnormally.
He accepted an Opecator's shutting down the High Pressure Injec-tion System on March 29, 1978, one year before the accident. He accepted an Operator's shutting down the rIigh Prescure Injection
( System the morning of the accident which damaged the reactor core.
[ The Station Manager did not set a standard for operating Three Mile Island. He did not require that Operators operate the nuclear plant in accordance with design. He did not require
[ that Operators operate in accordance with Technical Specifica-L tions and Station Procedures.
The Station Manager accepted Operators' operating Three Mile
( Island Unit 2 nuclear plant as they t.hought best under prevail-ing circumstances.
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Operators caused serious damage to the Three Mile Island Unit 2 reactor core by operating as they thought best but contrary to desig...
An Operator shut down the High Pressure Injection System at 0403, March 28, 1979.
The Shift Supervisor stopped reactor coolant pumps after the reactor scram on March 28, 1979. He stopped the pumps becauce
{, reactor coolant system pressure was low and the pumps were vibrating.
Stopping reactor coolant pumps stopped circulation of coolant through the reactor core and the core was damaged.
Stopping reactor coolant pumps was contrary to design.
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( Operators increased damage to the reactor core by operating Unit 2 nuclear plant as they thought best during the accident on March 28, 1979.
Operators opened the block valve with the electromagnetic relief valve open at 0713. Operators opened these valves together frequenta.y between 0713 and 1732.
Opening these valves increased damage to the reactor core.
l Opening these valves is contrary to design. i f
The Primary Plant Operator shut down the High Pressure In- !
jection System at 0817 and 1351. He did not start the System at j 0819.
If the Hign Pressure Injection System had operated as designed at 0817, 0819, or 1351, damage to the reactor core would have been less severe.
The Problem at Three Mile Island was:
Operators operated Unit 2 nuclear plant as they thought best under preveiling circumstances. The Station Manager subscribed to this way of operating.
Operators operating Three Mile Island Unit 2 nuclear plant as they thought best under the circumstances prevailing on March
{ 28, 1979, caused serious damage to the reactor core.
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Managing Three Mile Island The High Pressure Injection System The Three Mile Island Unit 2 High Pressure Injection System pumped sodium hydroxide into the reactor coolant system twice.
Sodium hydroxide is harmful to the reactor coolant system and Unit down time is required to remove this chemical. A High Pressure Injection System which pumps sodium hydroxide into the reactor coolant system is deranged. 1 The Station Manager should have directed the Maintenance Superintendent to repair the High Pressare Injection System when sodium hydroxioe was pumped into the reactor coolant system.
t An Operator shut dowr the Hich Pressure Injection System I following a reactor scram on March 29, 1978. He shut down the High Pressure Injection System to prevent sodium hydroxide from being pumped into the reactor coolant system.
The Station Manager should have directed the Maintenance Superintendent to repair the High Pressure Injaction System on March 29, 1978.
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If the High Pressure Injection System was repaired before r March 29, 1978, the Station Manager should have directed that
( the System be tested oecause Operators questioned the l operability of the System. l
( Tne Station Manager snould have required that operators be l informed when the High Pressure Injection System tested satis- l factory, was returned to service, and operating in accordance with specificatons.
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The Station Manager should have directed all Managers and r Operators to operato the High Pressure Injection System as L designed and as stipulated in Station Procedure 2202-1.3.
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Tne Block Valve for the Electromagnetic Relief Valve r
l Three Mile Island Unit 2 Operators were concerned that the block valve for the electromagnetic relief valve would stic< if used too often. The block valve was repaired in September 1977.
The Station Manager shou.'d have required that the block valve for tne electromagnetic relief valve be tested tollowing
( repairs in September 1977. He should have directed the Mainten-ance Superintendent to repair the valve a Tin if tests showed the valve did not meet specifications.
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( The Station Manager should have required that Operators be informed when the block valve was repaired, tested satisfactory, returned to service,.and operating in accordance with specifica-
{ tions.
The Electromagnetic Relief Valve Steam started to leak from the Three Mile Islano Unit 2 reactor coolant system through the electromagnetic relief valve in the Fall of 1978.
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Operators should have closed the block valve when the temp- )
r erature of the discharge pipe showed that the electromagnetic l' relief valve was leaking steam.
l Operators considered the block valve unreliable, however. .
The Station Manager should have required that Operators close the block valve to stop the steam leak through the electromagnetic relief valve. He should have required Operators to use the block valve as designed and as stipulated in Station Procedure 2202-1.5.
The Reactor Coolant System Leak A leak in the reactor coolant system of Three Mile Island Unit 2 started in the Fall of 1978 when steam started to leak from the electromagnetic relief valve.
If the block valve had been closed and tne leak stopped,
( Unit 2 reactor plant could have operated as designed to generate electrical power for Metropolitan Edison. The Station Manager could nave directed that plans be made to copair or replace the
( relief valve during the next plant outage.
time would have been minimized.
Reactor plant down The reactor coolant system leak at Three Mile Island Unit 2
[ became worse on March 28, 1979. Calculations for the hour 0134 to 0234 showed an increase in the reactor coolant system leak r rate to 6.94 gallons per minute. Operators were pumping more
( water from the tank to which the leak drained.
The Shift Supervisor should have shut the block valve or shut the Unit 2 reactor plant down about 0300. The reactor coolant system leak at this time showed serious degradatlan of the reactor coolant system pressure boundary.
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The Shift ~ Supervisor should have shut the reactor plant down-to trouble e'noot the reactor coolant system leak and instigate repairs.
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Damag9 to the Reactor Core
( Operators were operating Three Mile Island Unit. 2 on March 28, 1979, with a deranged safety system, the reactor coolant Fystem leaking, and a relief valve showing open. The block valve for the relief valve was unreliable. Operators were oper-
{ 'ating three reactor plant systems abnormally because of the reactor coolant system leak.
[ A Manager with responsibility for proper operation of Three Mile Island Unit 2 should have been stationed in the Control l Room on March 28, 1979.
r A Manager in the Control Room with responsibility for proper operation of Three Mile Island Unit 2, would have learned when he came on shift about midnight, that the reactor coolant system was leaking and the electromagnetic relief valve was showing open. lie would have learned that the raactor coolant makeup system, the reactor coolant drain system, and the pressurizer u system were being operated abnormally because of the reactor i coolant system leak.
{y
[ lie would have experienced an increase in the reactor coolant system leak rate during the first 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> of his shift.
{, lie would have experienced the following:
l 0400 Reactor Scram I r 0402 fligh Pressure Injection System actuated by low L reactor coolant system pressure 0403 Primary Plant Operatot shuts down liigh Pressure Injection System
( 0407 0410 Reactor building sump pump starts Raactor building sump alarms on high level 0414 Beactor coolant drain tank rupture disc ruptures; reactor building pressure increases
[ 0415 Leactor coolant pumps alarm due to low teactor coolant system pressure 0415 Shitt Supervisor leaves Control Room
( 0418 Reactor building radiation monitors show 10 times normal reading 0422 Reactor power increases
( 0422 Reactor coolant pump alarms due to hign vibration 0433 Alarm-high temperature in reactor core 0500 Snift Supervisor returns to Control noon
( 0514 Shitt Supervisor orders reactor coolant pumpa in B loop stopped
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Tne Manager in the Control Room would have recognized a loss of coolant accident and ordered the Operator to operate the High
[ Pressure Injection System as designed.
r The Manager in the Control Room would have recognized the I loss of coolant accident and ordered the High Pressure Injection System operated before 0500.
( The High Pressure Injection System would have pumped coolant into the reactor coolant system at 1000 gallons per minute.
System pressure would nave increased and reactor coolant pumps would have continued to circulate coolant through the reacter
[ core. Decay heat would have been removed from the reactor core as designed, b Reactor coolant pumps would have operated properly when reactor coolant system pressure increased so there would have been no need to stop the pumps when the Shift Supervisor
( returned to the Control Room at 0500.
The accident would have been terminated before the reactor core incurred serious damage.
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Station Manager's Responsibility
( The Station Manager is responsible for proper operation of Three Mile Island Unit 2. He permitted derangements to reactor plant systems and equipment to go unrepaired, hcwever.
( Operators therefore operated the reactor plant abnormally and contrary to design.
If the Station Manager had managed Three Mile Island to generate electrical power for Metropolitan Edison by ensuring that the Unit 2 nuclear plant was operated as designed, the
( reactor core would not nave been damaged.
Three Mile Island Unit 2 would now be capable of generating designed electrical power f or Metropolitan Edison instead of
( being shut down with serious damage to the reactor core.
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Metropolitan Edison Corporate Management Responsibility for Three Mile Island r- Metropolitan Edison Company is responsible for the design L- ad operation of the Three Mile Island Unit 2 nuclear power L
plant.
[ Three Mile Island Unit 2 is designed to generate 906 mega-watts of power. The reactor core is designed and built to produce; power with the nuclear fuel at the proper temperature.
The reactor coolant system is designed and built to transfer
( #^ power from the reactor core with the core at the proper temper-ature. Safety systems are designed and built to maintain the temperature of the nuclear fuel at a safe level if an abnormal
[ condition develops in the nuclear plant.
Metropolitan Edison developed Technical Specificatons to be
( followed in operating Three Mile Island Unit 2. Unit 2 Techni-cal Specifications identify the plant's designed operating con-dicions. Technical Specifications cite safety limits, safety ,
system settings, and limiting conditivas for operating which i ensure that the plant operates as designed. Technical Specifi-cations cite testing required to ensure that syatems and equipment operate as designed.
Unit 2 Technical Specificatons stipulate that Unit 2 is to 1 be operated in accordance with Station Procedures developed from '
( Tecnnical Specifications. Operating Unit 2 in accordance with procedures developed from Technical Specifications ensures that l Unit 2 is operated as designed.
( Metropolitan Edison Company is licensed by the Nuclear Regulatory Commission to operate Three Mile Island Unit 2 as a commercial facility. The Nuclear Regulatory Commission issued
[ an Operating License to Metropolitan Edison by authority of Congress. Three Mile Island Unit 2 Technical Specifications are a part of the Operating License for Unit 2.
Three Mile Island Unit 2 Technical Specifications and Station Procedures are Rules to be followed by all Metropolitan
( Edison and Three Mile Island personnel responsible for Three Mile Island Unit 2. Tnree Mile Island Unit 2 Technical Specifi-cations and Station Procedures are Rules to be followed by
[ Metropolitan Edison Company Corporate officials in managing the operations of Three Mile Island Unit 2.
( Metropolitan Edison Corporate Officials and the Accident on March 28, 1979
( A Metropolitan Edison Corporate Official learned that Three Mile Island Unit 2 had had an accident during a telephone call from the statica about 0600. The Vice President, Generation Metropolitan Edison was told during this telephone call that a
(- reactor scram had occurred, the scram was abnormal, and reactor cralant pumps were off. Participants in this call agreed that r circulation of coolant through the reactor core had to be L reestablished.
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( The President of Metropolitan Edison was told about 0755 that an accident had occurred at Three Mile Island.
The' Vice President Generation, Metropolitan Edison, called
( the station at 0910 and 1010 to learn the status of the plant.
He went to the Station's Observation Center at 1140. He called the Unit 2 Control Room f rom the Observation Center and talked
( L to the Station Manager.
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A representative of Three Mile Island's nuclear plant !
contractor participated in the 0600 call with the Station
[ ', , Manager and the Vice President Generation, Metropolitan Edison.
Babcock and Wilcox's Site Representative notified Babcock and l Wilcox Corporate of ficea in Lynchburg, Virginia that an accident
( had cccurred at Three Mile Island Unit 2. He called Lynchburg at 0745. The Manager of Plant Startup Services at Lyncnburg formed a special task force following this telephone call.
[
(! The Babcock and Wilcox Manager of Project Management called the Vice President Generation, General Public Utilities at 1400. He recommended thac at least 400 gallons of coolant per
( minute be pumped itto the reactor coolant system. Babcock and 3
Wilcox also passed chis recommendation directly to Three Mile Island.
At 1402, one High Pressure Injection Pump was pumpit.q coolent at the rate of 113 gallons per minute into the re0ctor coolant system. At 1501 one pamp was pumping 95 gallons per
. minuto into tha reactor coolant system.
[
i At 1600, the Babcock and Wilcox Task Force recommended to Three Mile Island that High Pressure Injection flow be estab-( lished at 400 to 500 gallons per minute. The Task Force also 19 commended that High Pressure Injection flow be maintained to
'r increase reactor coolant system pressure to above saturation in L order to operate a reactor coolant pump.
(
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[ At 1602, High Pressure Injection flow was 116 gallons per minute and at 1701 flow was 128 gallons per minute. Coolant was being drained from the reactor coolant system at the rate of 120 gallons per minute at 1630 and 1645.
[t ,
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The Babcock and Wilcox Manager Project Management told the Vice President Generation, General Public Utilities, between
( 1630 and 1700, that High Pressure Injection flow of 400 to 500 gallons per minute should be initiated.
The Vice President Generation, Metropolitan Edison returned
[ to Three Mile Island from the Pennsylvania Lieutenant Governor's office about 1630. After being oriefed on the plant status and trends, he called the Vice President Generation, General Public
[ Utilities. During this conversation, the Vice President Genera-tion, Metropolitan Edison and the Vice President Generation, General Public Utilities decided that Thtee Mile Island Unit 2 must be repressurized.
(
The Vice President Generation, Metropolitan Edison directed the Station Manager to repressurize the Three Mile Island Unit 2
[ teactor coolant system after his telephone call with the Vice President Generation, General Public Utilities.
( The Station Manager directed that the reactor coolant system be repressurized. Operators shut the block valve and increased reactor coolant system pressure from 623 psig to 2300 psig
( between 1732 and 1846. At 1723, 2 High Pressure Injection Pumps were pumping coolant at the rate of 460 gallons per minute into the reactor coolant system.
One reactor coolant pump was started and run at 1950. At 1950, one reactor coolant pump was pumping reactor coolant through the reactor core and one steam generator. The ateam
( geaccator was steaming to the main condence.r to remove decay heat from the reactor core.
[ The reactor plant was being oper.ated as designed to remove decay heat from the reactor core. Stable plant conditions were finally reached.
[
[
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[ The Vice President Generation, Metropolitan Edison did not require that Three Mile Island Unit 2 be operated as designed.
He did.not require that Three Mile Island Unit 2 be operated as r designed before the accident. He did not. require that Unit 2 be ,
L operated as designed when he first learned about the accident at 0600, March 28, 1979. He did not require that Unit 2 be oper-ated as designed at 0910 or 1010. He did not require that Unit
[-- 2 be operated as designed after his arrival at the Station at 1130.
[ The Vice President Generation, Metropolitan Edison directed that Three Mile Island Unit 2 be operated as designed sometime after 1630.
Operators regained control of Three Mile Island Unit 2 by operating the nuclear plant as designed'after receiving orders from the Vice President Generation, Metropolitan Edison.
[
[
Metropolitan Edison Company is responsible for the proper operation of Three Mile Island Unit 2 in accordance with the
{
Operating License issued by authority of Congress.
- If the President of Metropolitan Edison Company had discharged his responsibility for the proper operation of Three
[ Mile Island Unit 2, by promulgating a Policy for the proper operation of Three Mile Island Unit 2, and
( If >:he President's Policy for operation of Three Mile Island required that Unit 2 be operated in accordance with the plant's Operating License / Technical Specifications and Station Proce-dures developed from Technical Specifications, and
{
If the Vice President Generation, Metropolitan Edison had r implemented the Policy for proper operation of Three Mile Island L Unit 2:
The Station Manager would have managed Three Mile Island so
[ that Unit 2 nuclear plant was operated in accordance with design {
to produce electrical power for Metropolitan Edison.
If the Station Manager had managed Three Mile Island so that
( Operators operated Unit 2 in accordance with design, the accident on March 28, 1979 would not have occurred.
Three Mile Island Unit 2 would now be available to produce 906 megawatts of electrical power for Metropolitan Edison in-stead of being shut down with a severely damaged reactor core.
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s in A_ Corrective Action Program for Three Mile Island President Metropolitan Edison Company promulgate a Policy for the operation of Three Mile Island. For example:
METROPOLI'1 AN EDISON COMPANY f PRESIDENT'S ORDER NO.
l S ubj ec t. : Company Policy for Operating' Three Mile Island Nuclear Station Policy:
{
Metropolitan Edison Company's nuclear statio..a shall bc
)
r operated in accordance with the Facility Operating License /
l Technical Specifications. Other company activities supporting the operations at Three Mile Island shall also be conducted in ;
accordance with the Facility Operating License / Technical
( Specifications.
Operating Three Mile Island and conducting other activities in support of operations in accordance with this directive,
{ requires adherence to and compliance with Station Procedures. l j
r Signed L
l President '
Metropolitan Edison Company L
(
r Vice President Generation, Metropolitan Edison Company L promulate an Order and implement the President's Policy for operating Three Mile Island. The Vice President's Order to contain an Objective for the Station.
For example:
METROPOLITAN EDISON COMPANY VICE PRESIDENT'S ORDER SO.
(
Subject:
Operation of Three Mile Island Units 1 and 2
( To Station Manager
{
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[ You are hereby directed to manage Three Mile Island so that Units 1 and 2 are operated in accordance with design to produce electrical power for Matropolitan Edison.
You are directed to reanage Three Mile Island so that:
(1) Units 1 and 2 operate in accordance with each Facilities' Operating License / Technical Specifications; (2) other activities
[ at Units 1 and 2 are conducted in accordance with each i Facilities' Operating License / Technical Specifications. .
[ You shall adhere to the Policy for operating and conducting other activities at Three Mile Island set forth in President's Order No. .
You are directed to manage Three Mile Island Units 1 and 2 to produce electricity in accordance with the schedule issued under my signature.
Signed _
( Vice President, Generation Metropolitan Edison Company
[
[ The President's Policy sets a standard for the quality of work at Three Mile Island.
[ The Vice President's Order sets an Objective for the output of power and other work at Three Mile Island. The Station Ob-jective is to meet a schedule for operations, maintenance and re-fueling promulgated by the Vice President.
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( Station Manager organize Three Mile Island to use the re-sources of the station economically and efficiently to achieve' the Objective assigned the Station. .
t
(' For Example: - -# - 1 p Make a Station Superintendent responsible for proper O operation of Three Mile Island nuclear plants. Assign a Station Superintendent with this responsibility, to Three Mile Island on
[,' '
a shift basis: a Station Superintendent for each shift, three shifts a day, every d y. 4 Make the Station Superintendent responsible for meeting the
- Station Objective during his shift. Assign him the resources
); necessary to meet the Station Objective. Station resources include manpower necessary to operate and accomplish work an-I r signed his shift. Work to be accomplished includes refueling I
( wnen schedeled, and maintenance and repair work. !
Make the Station Superintendent accountable for the safe,
[ efficient and economical use of station resources assigned in accomplishing the Station Objective on his shif t.
(; Promulgate a Directive for Station Superintendents.
For Example:
( Metropolitan Edison Company Three Mile Island Station Station Manager's Order No.
s S ubj ect: Duties, Responsibilities and Autnority of Station Superintendent
(
TO: Station Superintendent The Station Objective for Three Mile Island Unit 2 is to generate electricity safely, reliably and economically, and
[ deliver the electricity generated to the transmission system in accordance with the schedule promulgated by the Vice President Generation, Mccropolitan Edison.
You are responsible for operating Three Mile Island Units 1 and 2 during your shift to cchieve the Station Objective.
[ You are also responsible for conducting other activities ass!,yned your shift to achieve the Station Objective.
23 ID4: 4267A/ DISC:0068A
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( To achieve the Station Objective you are to:
- a. Operate Three Mile Island Units 1 and 2 nuclear plants
[ and supporting systems and equipment to produce L electricity when scheduled. Operate means to Operate or Maintain the Unit in the Ref ueling Mode, Cold Shut-r down, Hot Shutdown,llot Standby, or Low Power Physics
[ Testing, as defined in Technical Specifications,
- b. Conduct surveillances required by Technical
( Specifications.
- c. Conduct maintenance work scheduled on the nuclear plants and supporting systens and equipment.
{
- d. Refuel the nuclear plants when scheduled.
( In achievinn the Station Objective, saf ely, reliably and 1 economical 1}:
[ a. Safely .ceans in accordance with the Facility Operating
- Lice.ase, Technical Specifications and Station Proce- I dures and Codes and Standards.
- b. Reliably means to operate or perform the other i functions so as to meet the schedule for Three Mile Island Units 1 and 2 promulgated by the Vice President,
[ Generation, Metropolitan Edison.
- c. Economically means to perform all functions using
( Station resourcec assigned you in an efficient and effective manner. Station resources are manpower, machinery and equipment, time and budgeted funds.
You are to achere to the Policy for operating Three Mile Island promulgated in President Metropolitan Edison's Order No. .
( Signed Manager Three Mile Island
(
(
{
[ 24 ID8: 1267A/ DISC: 0068A
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r Make a Shift Engineer responsible for proper operation of '
Three Mile Island Unit 2.
f Station the Shift Engineer in the Control Room and give him L authority over the Operators on shift.
Make the Shift Engineer accountable to the Shift Superviser
[ tor proper operation of Unit 2.
Promulgate a Directive for the Shift Engineer.
{s For Example:
Metropolitan Edison Company Three Mile Island Station Station Manager's Order No.
Subj ect: Duties, Responsibilities and Authority of Shift Engineer To: Shift Engineer
(
The Station Objective for Three Mile Island Unit 2 is to
[ generate electricity safely, reliably and economically and L
deliver the electricity generated to the transmission system in accordance with the schedule promulgaced by the Vice President Generation, Metropolitan Edison.
You are responsible for operating Theme Mile Island Unit 2 during your shift to achieve the Station Oojective.
[ To achieve the Station Objective you are to
- a. Operate Three Mile Island Unit 2 nuclear plant and
{ supporting systems and equipment to produce electricity when scheduled. Operate means to Operate or Maintain the Unit in the Refueling Mode, Cold Shutdown, Hot Shutdown, Hot Standby, or Low Power Physics Testing an defined in Technical Specificatons.
( b. Condoct survuillances required by Technical Specifica-tions.
In achieving the Station Objective, caf ely, reliably and economicallyt
- a. Safely means in accordance with the Facility Operating
[ License, Tecanical Specifications and Stction Proco-durea.
25 IDt: 1267A/ DISC:0068A
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- b. Reliably means to operate or perform the other functions so as to meet the schedule for Thret Mile Island Unit 2 promulgated by the Vice President, Generation, Metropolitan Edison.
- c. Economically means to perform functions assigned using resources assigned in an efficient and effective manner. Resources are rianpower, machinery and equipment, time and budgeted funds.
You are responsible for controlling the status of Three Mile Island Unit 2 components, systems and equipment. Control means to maintain components systems and equipment in a proper con-dition while operating, conducting surveillances, testing or performing maintenance work. A proper condition 4* lined up for service or in a condition to ensure the safety and reliability of the component, system or equipment or associated components, l systems and equipment.
You are to adhere to the Policy for operating Three Mile
{ Island Unit 2 promulgated in President Metropolitan Edison's Order No. .
l You shall exercise authority over Station Operators in i discharging your responsibility.
You shall report to the Shift Supervisor in the performance l of your duties.
Signed _
( Manager Three Mile Island f
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26 IDitl267A/ DISC 1006SA
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( Make the Shift Supervisor responsible for proper operation '
of the Three Mile Island Nuclear Plants.
(' Make che Shif t Supervisor accountable to the Station Superin-C tendent for proper operation of Three Mile Island Nuclear Plants in achieving the Station Objective.
( Assign Shift Engineers stationed in Three Mile Island Control Rooms to the Sift Supervisor.
{ Promulgate a Directive for the Shift Supervisor.
For example:
Metropolitan Edison Company Three Mile Island ."ation l Station Mant r 's t .for No.
S ubj ect: Dutier, Responsibilities .3 Authority of Shift Supervisor
{
To Shift Supervisor The Station Objective for Three Mile .131and is to generate electricity safely, reliably and economically and deliver the electricity generated to the transmission system in accordance f with the schedule pr^mulgated by the Vice President Generation, -
Metropolitan Edison.
( You are responsible for operating Three Mile Island Units 1 and 2 during your shift to achieve the Station Objective.
To achieve the Station Objective you are to:
[
- a. Operate Three Mile Island Units 1 and 2 nuclear plant i and supporting systems and equipment to produce j electricity when e 7heduled. Operate means to Operate l or Maintain the Ut.at in the Refueling Mode, Cold l Shutdown, Hot Shutdown, Hot Standby, or Low Power
( Physics Testing as defined in Technical Specificatons.
- b. Conduct surveillances required by Technical Specifica-tions.
{
In achieving the Station Objective, safely, reliably and economically:
- a. Safely means in accordance with the Facility Operating License, Technical Specifications and Staticn Proce-dures.
[
27 ids: 1267A/ DISC:006SA f -
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- b. Reliably means to operate or perform the other functions so as to meet the schedule for Three Mile Island promulgated by the Vice President, Generation, Metropolitan Edison.
- c. Economically means to perform functions assigned using 7
resources assigned in an efficient and effective l manner. Resources are manpower, machinery and equipment, time and budgeted funds.
( You are responsible for controlling the status of Thre; Mile Island Unita 1 and 2 components, systems and equipment. Control means to maintain components systems and equipment in a proper condition while operating, conducting surveillances, testing or per f orming r..aintenance wor k. A proper condition is lined up for service or in a condition to ensure the safety and reliabil- ity of the component, svstem or equipment or associated compo-nents, systems and equipment.
( You are to adhere to the Policy for cperating Thcee Mile Island Unit 2 promulgated in President Metropolitaa Edison's Order No. .
You shall exercise authority over Shift Engineers and Station Operators in discharging your responsibility.
[ You shall report to the Shift Superintendent in the performance of your duties.
[ Signed _
Manager Three Mile Island
[
[
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THE STUDY r
L EVEN'"S Accident Begins Managers Are Called
{ Shift Supervisor ud Superintendent Technical Support Stop Reactor' Coolant Pumps Other Managers Becomo Involved Core Flood Tank Valves Closed
[ Corporate Management is Informed Block Valve is Closed; Reactor Coolant System Leak'is Stopped;-
Reactor Coolant Pump is Started
(
Managers Disc n Fuel Failures Station Manager Arrives p
Reactor Coolant Pump is Stopped Operators Reestablish Reactor Coolant System Leak Emergency Safeguards Signal Initiated - Twice
[
Station Maneger kepressurizes Reactor Coolant System - System is Depressurized Again Vice President Generation, Metropolitan Edison, Comes to Three Mile Island Another Emergency Safeguards Signal
[ Vice President Directs Reactor Coolant System Repressurized 1
[
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A THREE MILE ISLAND OPERATORS OPERATING THE PLANT b operator Shuts Down Safety System Operators Block Safety System Operator Reestablishes Reactor Coolant System Leak Operator Shuts Down Safety System o Operator Does Not Start Safety System h' Operator Shuts Down Safety System l
]
THREE MILE ISLAND MANAGERS MANAGING OPERATIONS Superintendent Technical Support, Station (.. nager and the Safety System Shutdown f
Superintendent Technical. Sur.por t Cor. curs; Reacte, "cM ?.n t Pumps are Stopped i Station Manager, Unit 2 Superintendent and Reactor Coolant Pumps g Station Manager, Unit 2 Superintendent, Unit 1 Operations l Supervisor, and the Reactor Coolant System Leak Vice President Orders Reactor Coolant System Repressurized NUCLEAR PLANT DESIGN Damage to the Three Mile Island Roactor Core and Nuclear Plarit Design Three Mile Island Operators, Managers, and Station Procedures
( Nuclear Plant Design, Station Procedures and Plant Technical Specifications Vice President's Order; Control of Three Mile Island Unit 2 is
{ Regained l
l l Consequences of Disregarding Station Procedures and Plant l Tecnnical Specifications Authority of a Nuclear Power Plant's Technical Specifications Turning of f High Pressure Injection and Pressuri::er Level f
{ _ - _ -- _ ---- - -------- --------- --- - -- ------- ----
1 L.4 *
,y ERRORS AT THREE MILE ISLAND
. Primary Plant Operator 's Error Other Operator Errots
( Errors - Superintendent Technical Support Errors - Station Manager
' Errors - Unit 2 Superintendent r' Errors - Unit 1 Operations Supervisor L
l Action by Vice President Generation, Metropolitan Edison I'
t A CORRECTIVE ACTION PROGRAM Causes of Operator Errors and Corrective Action l
Causes of Managers' Errorc and Corrective Action 1
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EVENTS Accident Begins The accider.t at Three Mile Island Unit 2 on March 28, 1979,
( started at 0400 with a loss of feedwater and turbine trip; a reactor scram followed in 8 seconds.
( An Emergency Safeguards Signal was initiated two minutes later as reactor coolant system pressure decreased to 1640 psig because a relief valve stuck open during the pressure transient
( following the reactor scram. The Emargency Safeguarde Signal started the High Pressure Injection System - 2 pumps pumping 1,000 gallons of borated water per minute into the teactor coolant system.
One minute eleven seconds after the Emergency Safeguards Signal was initiated, an Operator turned off the Emergency
[ Sateguards Signal and shut down the High Pressure Injection System. Reactor Coolant System pressure was decreasing and pressurizer level was in the normal range, less than 2/3 full.
Managers are Called The Unit 2 Shift Supervisor had the Station Manager, Gary Miller called at 0401 and informed of the turbine trip and reactor scram. Joseph Logan, Unit 2 Superintendent, and Geo.cge
( Kunder, Superintendent - Technical Support, were informed at approximately 0410. Kunder, being the "duty section head", came to the site arriving at about 0450.
( Kunder, on arrival in the Control noom, was informed of problems being experienced: pressurizer level high, reactor r coolant system pressure low, reactor coolant drain tank rupture l disc blown. He was also informed that an Emergency Safeguards Signal had started the High Pressure Injection System following the 0400 reactor scram.
Reactor coolant system pressure was 1120 psig and pres- '
surizer level was 380 inches at 0430 as indicated on the control room strip charts.1 Tne charts showd 1110 psig reactor
( coolant pressure and 390 inches pressurizer level at 0500.
I Shift Supervisor and Superintendent Technical Support Stop Reactor Coolant Pumos
( The four reactcr coolant system pumpa were stopped on the decision of the Shift Supervisor and George Kunder due t) low suction pressure.
l ID4 : 12 7 2 AD ISC : 00 6 8 A
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The two pumps in B loop were stopped at 0514, and the two
( pumps in A loop were stopped at 0541.
The pumps were stopped because reactor coolant system r pressure had decreased below the minimum required for operating l pumps, pumps were vibrating and a decision was made to go to natural circulation.
( Reactor coolant system pressure and temperature were well outside prerequisite pressure and temperature conditions for establishing natural circulation at 0541.
( Operators did not believo that natural circulation started because the reactor coolant hot leg temperature was 5300F while pumps were running but this temperature increased to 6200F after pumps were stopped.
Reactor coolant system pressure was 1110 psig and
( pressurizer level was 390 inches at 0530 as indicated on control room strip charts.1
( Other Managers Become Involved
( Gary Miller , Station Manager, called the station f rom his L
home at about 0515 to ascertain the status of the plant.
Kunder told him the plant conditions. Plant conditions
( were; reactor coolant system pressure 1100 psig; pressurizer level 390 inches;l High Pressure Injection System - off.
( Kunder told him that an Emergency Safeguard Signal initiated by low reactor coolant system preusure had started the High Pressure Injection System following the 0400 reactor scram.
Joseph Logan, Unit 2 Superintendent, arrived on site at approximately 0545 and proceeded to the Unit 2 Control Room where he was briefed by the Shift Supervisor and Kunder.
Michael Ross, Unit 1 Operations Supervisor, reported to the Unit 2 Control Room at 0600. Ross had been at the Station since
( about 0530 to assist with the start up of Unit 1.
Core Flood Tank Valves Closed j Operators closed the two core f'.ood tank flood valves at 0600 to prevent the addition of reactor coolant water to the
(' reactor coolant system. Reactor coolant system pressure was 790 psig decreasing.
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Corporate Management is Informed After his 0515 call to the station, Gary Miller decided to make a conference call. Accordingly, calling from his home at 0600, Miller discussed the situation at Three Mile Island with Joan Herbein, Vice president Generation, Metropolitan Edison and Leland Rogers, Babcock arid Wilcox, Site Operation Manager, both at their homes. George Kunder participated from the Unit 2 Shift Supervisor's office. The status of the plant was dis-cussed. participants in the call knew that the reactor scram was abnormal since reactor coolant pumps were off. During the call, the condition of the electromagnetic relief valve was
{ questioned and the valve was reported shut.
r The block valve for the electromagnetic relief valve - open
( when this telephone call commenced - was closed during the call.
l Reactor coolant system pressure was 790 psig and pressuri::or
( level was 290 inches at 0630 as indicated on control room strip chs'. t s .1 Block Valve is Closed; Reactor Coolant System Leak is Stopped; Reactor Coolant Pump is Started
[ The block valve for the electromagnetic relief valve was closed at 0618 stopping the reactor r.:oolant system leak which had existed since the electromagnetic relief valve stuck open
( just after the reactor scram at 0400.
An operator closed the block valve because he saw that the
{ temperature of the relief valve's tail pipe indicated the relief valve was open.
[ Reactor coolant pressure then began to increase from 660 t psig the low point, to a pressure which permitted operating reactor coolant pumps.
( Accordingly, Logan, Unit 2 Superintendent; Kunder, Unit 1 Technical Superintendent; atid Ross, Unit 1 Operations Super-visor, recognizing the need to re-establish core cooling, super-( vised attempts to start the pumps.
At 0654, with reactor coolant pressure about 1400 psig, I
[ reactor coolant pump 23 was started, Reactor coolant system L
pressure increased to 2200 psig while the pump was running. The pump ran for 19 minutes. l l
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Managers Discern Fuel Failures f
Responding to a radiation alarm, the Station Chemistry /
Health Physics Supervisor discovered radiation levels of 600 t millirem per hour in the vicinity of reactor coolant system I sample lines. He reported these results to George Kunder.
Kunder reported the information to Joseph Logan, Unit 2 Super-intendent, along with his belief that fuel failures were being l experienced. The Station Manager was called and given this in-formation about 0650.
Station Manager Arrives e
Gary Miller, Station Manager arrived at the site at approxi-I mately 0705. He proceeded to the Unit 2 Control Room where he was briefed by his Managers and the Shift Supervisor.
( Miller declared himself the Emergency Director and estab-lished an Emergency Command Team as follows: Michael Ross, Unit 1 Operations Supervisor, was placti in charge of operations to direct the Shift Supervisor,
(
Joseph Logan, Unit 2 Superintendent, was placed in charge of reviewing and verifying that personnel complied with procedures
( and plans.
George Kunder, Superintendent Technical Support, was put in
( charge of notifications, communications, and technical support.
Leland Rogers, the Babcock and Wilcox Site Manager, who
{ arrived on site about 0715, was requested to provide technical assistance and communicacions with Babcock and Wilcox.
[ Reactor coolant system pressure was 2100 psig and pres-( surizer level was 370 inches at 0700 as indicated on room strip charts.1 Reactor Coolant Pump Is Stopped
( After attempts to establish natural circulation failed, Operators started reactor coolant pump 2B at 0654. However, based on a no flow indication and the fact that the pump was r drawing only 100 amps, at 0713, Ross, Unit 1 Operations Super-t visor, and the Shift Supervisor, stopped the pump.
( Operators Re-establish Reactor Coolant System Leak Pressure increase in the reactor building at 0713 suggests
{ that an Operator opened the block valve with the electromagnetic relief valve open in manual. Reactor coolant system pressure and 4 ID4:1272A/ DISC:0063A
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pressurizer level both dropped; reactor coolant system pressure to 1975 psig and pressurizer level to 300 inches. The pressure
( increase in the reactor building stopped about 3 minutes later, suggesting the electromagnetic relief valve discharge path to the reactor building was again isolated.
An attempt was in progcess to control pressurizer pressure and level with the electromagnetic relief valve.
Emergency Safeguards Signal Initiated - Twice An Emergency Safeguards Signal was initiated by high reactor building pressure at 0756. This Signal started the High Pres-
[ sure Injection System - 2 pumps pumping borated water at the L
rate of 1000 gallons per minute into the reactor coolant Sys-tem. The Emergency Safeguards Signal also initiated reactor bui) ding isolation.
An Operator turned off the Emergency Safeguards Signal and defeated reactor building isolation at 0800. He shut down the
[ High Pressure Injection system at 0817.
An Emergency Safeguards Signal was again initiated by high reactor building pressure at 0819. The High Pressure Injection
{ System was signaled to start but no pumps started because the System was not lined up. The Emergency Safeguards Signal also r initiated reactor building isolation. Eighteen seconds after l this Safeguards Signal awas initiated, an Operator defeated the Saf eguards Signal and r eactor building isolation.
( Reactor coolant system pressure was 1500 psig and pres-surizer level was 380 inches at 0800 as indicated on control room strip charts.1 Station Manager Repressurizes Reactor Ccalant System - System is Depressurized Again At 0915, George Miller, Station Manager, directed the reactor coolant system pressure be maintained between 2000 psig
( and 2100 psig. Accordingly, the electromagnetic relief valva wa: verified closed and high pressure injection pumps were used to increase system pressure. System pressure increased from 1250 psig at 0924 to 2110 psig at 1006. Pressure was then con-( trolled between 2000 psig and 2l00 psig by opening the electro- l magnetic relief valve and block valve. I This condition was maintained until 1130 when an Operator opened the electromagnetic relief valve and block valve to de-pressurize the system. The decision to depressurize the reac*.or I
( 5 ID4:1272A/ DISC:006SA
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coolant system was made by the staff to obtain core flood ir.jec-tion and enable operation of the decay heat removal system.
Commencing at 1150, the pressurizer vent valve was'also opened periodically.
Reactor coolant system pressure was 2140 psig at 1130. De-pressurization took approximately 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, system pressure de-creasing to 600 psig at 1241.
Vice President - Generation, Metropolitan Edison, Comes to Three Mile Island l
John Herbein, Vice-President Generation, Metropolitan Edison, arrived at the Three Mile Island Observation Center at 1140 and called the Station Manager again to learn the current plant status.,
He had called the Station about 0910 and learned the status of the Plant f rom George Kunder, Superintendent-Technical Support. He called again about 1010 and obtained an update from the Station Manager.
(
Another Emergency Safeguards Signal An Emergency Safeguards Signal was again initiated by high reactor building pressure at 1350. This Signal started the High
{ Pressure Injection System (2 pumps delivering reactor coolant water at the rate of 1000 gallons per minute to the reactor coolant system), started the reactor building spray pumps, and l l initiated building isolation.
An Operator defeated building isolation and shut down the l High Pressure Injection System one minute after the Emergency I safeguards Signal was initiated.
Reactor coolant system pressure was 550 psig at this time, f Pressurizer lavel was 400 inches.
Reactor coolar.t system pressure then varied between 450 psig and 650 psig until 1730.
( Operators were opening the electro-magnetic relief valve and block valve or the pressurizer vent valve to maintain low pressure.
f Pressurizer level also varied during this period. The level was 400 inches (full) from 1230 to 1430; level decreased to 175 inches at 1525; increased to full at 1630; and decreased to 275
{ inches at 1730.
At 1730, a change in operating procedure directed by
{ Metropolitan Edison Corporate Management, was instigated.
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9 Vice President Directs that Reactor Coolant System be Repressurized,
{
John Herbein, Gary Miller, and George Kunder returned from a f trip to the Lieutenant Governor's office at 1630 and were
( briefed on current plant status and trends. John Herbein talked with the Vice President-Generation,. General Public Utilities and between them it was decided that the plant must be repressur-( ized. John Herbein then directed the Station Manager to repressurize.
The block valve for the electromagnetic relief valvt' :.4
( shut.
I r At 1732 reactor coolant pressure was 623 psig. Pressure was i increased to about 2300 psig over the next 74 minutes using 2 high pressure injection pumps.
( Reactor coolant pump operations were reviewed and it was determined that reactor coolant pump 1A should be bumped. The pump was bumpod, reactor coolant pressure and temperature
( dropped and loop flow and reactor coolant pump current acted normally.
( After a 15 minute delay, at 1950, reactor coolant pump 1A l was started and left running. Reactor coolant pressure again dropped, but stabilized at about 1300 psig; and pressurizer level remained full scale.
I Reactor coolant pump 1A was pumping reactor coolant through the reactor core and "A" steam generator and steaming to the I
( main condenser to remove the decay heat from the reactor core. l l
Stable plant conditions, as the Emergency Command Team had defined them earlier, had finally been reached. '
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- THREE MILE ISLAND OPERATORS OPERATING THE PLANT Operator Shuts _Down Safety System A Three Mile Island Operator turned of f an Emergency Safe-guards Signal and shut down the High Pressure Injection Syqtem at the outset of the Three Mile Island accident.
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The High Pressure Injection System is a safety system de-signed to restore reactor coolant to the reactor coolant system
( to prevent fuel rods from overheating in case of a loss of coolant. At Three Mile Island the Emergency Safeguards Signal started the High Pressure Injection System because reactor
[ coolant system pressure decreased to 1640 psig due to a loss of L coolant.
Nuclear plant safety systems are required to be operable
( when the plant is operatii,q. At Three Mile Island, if for any reason, reactor coolant system pressure decreases to 1640 psig, the High Pressure Injection 3ystem is required to pump 1000 gal-
[ lons of reactor coolant water per minute into the reactor coolant system until system pressure is restored to normal.
f These stipulations are cor tained in Three Mile Island Unit 2 l Technical Specifications and Utation Procedures.2 f At Three Mile Island, the reactor coolant system would have
( prevented tuel rods from overheating by removing decay heat from the reactor core if the High Pressure Injection System had oper-ated as required by Technical Specifications and Station
( Proceduren.
Operators Block Safety Systen
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Three Mile Island Operators closed the cote flood tank flood r valves making the core flood system inoperable at 0600. The
( core flood system is a safety system nado ready for automatic operation by opening flood valves during plant start up in accordance with Three Mile Island Unit 2 Technical Specifica-( tions and Station Procedures.3 l l
The core flood system should have emained operable at 0600 '
in accordance with Technical Specifications and Station Proce-( dures.
( Operator Re-establisnes Reactor Coolant System Leak Tne block valve for the electrcmagnetic relief valve was
( shut at 0613 stopping the reactor coolant system leak.
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- c. An Operator opened the block valve with the electromagnetic
( relief valve open, at 0713, thus re-establishing the reactor coolant system leak. This was done frequently until 1732.
Operator Shuts Down Safety System A Three Mile Island Operator turned off an Emergency Safe-( guards Signal at 0800 and shut down the Ifigh Pressure Injection System at 0817.
( The Emergency Safeguards signal, initiated by high reactor buildfng pressure, started the liigh Pressure Injection System at 0756.
The liigh Pressure Injection System should have continued to operate at 0317 in accordance with Technical Specifications and r Station Procedures 2, because reactor coolant system pressure
( was below 1640 psig.
( Operator Does Not Start Safety System A Three Mile Island Operator turned of f an Emergency Saf e-( guards Signal 18 seconds after the Signal was initiated at L 0319.
The Emergency Safeguards Signal, initiated by high reactor {
( building pressure, signaled the Ifigh Pressure Injection System to start but the System did not start.
( The Operator should have started the !!igh Pressure Injection System at 0819 in accordance with Technical Specifications and Station Procedures 2 because reactor coolant pressure was below 1640 psig.
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The Operator did not start the system however.
Operator Shuts Down Safety System
( A Tnree Mile Island Operator shut down the liigh Pressure Injection System at 1351.
( An Emergency Safeguards Signal, initiated by high rei or building pressure, started the High Pressure Injection System at 1350, i
The Iligh Pressure Injecticn System should nave continued to l operate at 1351 because reactor coolant system pressure was below 1640 psi .
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, THREE MILE ISLAND MANAGERS MANAGING OPERATIONS L
Superintendent Technical Support, Station Manager and the Safety System Shutdown George Kunder, Unit 2 Superintendent Technical Support. was the first Three Mile Island Manager at the level of Superin-tendent to become involved in the accident.
When Kunder arrived in the Unit 2 control room about 0450,
( reactor coolant system pressure was belve 1640 psig.
An Emergency Safeguards Signal starts the High Press' ire
(_ Injection System when reactor coolant system pressure oserecsos i
to 1640 psig. Therefore, when Kunder arrited in the control room, the High Pressure Injection System should have been pumping reactor coolant back into the system at 1000 gallons per
( minute in accordance with Technical Specificatier,s and Station Procedures.2
( The High Pressure Injection System was not operating at 0450, however. The system had been turned off by an Operator at 0404 and the system remained off after Kunder's arrival.
When Gary Miller, Station Manager, called the Station at 0515, he discussed the status of the plant with Kunder for about r 20 minutes. He was told that reactor coolant system pressure
( was low and that the High Pressure Injection system had been turned off after the 0400 reactor scram.
( During the call, reactor coolant system pressure was below 1640 psig and the High Pressure System was off. The system re-mained off after Miller's call.
Superintendent Technical Support Concurs; Reactor Coolant Pumps are Stopped, George Kunder concurred with the action taken by the Shift Supervisor at 0541 to stop all reactor coolant pumps and go to
( natural circulation because of low pump suction pressure.
Kunder reviewed not positive suction head requirements for the pumps. He reviewed the Unit 2 Heat Up/ Cool Down Curve which is f in the Technical Specifications; in the Station Procedure for
( reactor coolant pumps; and in the Station Procedure for removal j of decay heat using steam generator,4 l
( Technical Specifications and Station Procedures require the reactor coolant system to be maintained within defined pressure I and temperature limits. Technical Specifications and Station
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[J-Procedures also require the liigh Pressure Injection System to pump coolant back into the reactar coolant system to restore
( system pressure to normal, if reactor coolant system pressure decreases to 1640 psig.2
{ Reactor coolant system pressure was low (1020 psig) at 0541 -
outside the pressure and temperature limits defined by Technical Specifications and Station Procedures. The Iligh Pressure 7.njec-(' tion System was off, however, having boon turned off by an Operator at 0403.
Station Manager, Unit 2 Superintendent, and Reactor Coolant Pumps r Kunder told Miller that ructor coolant pumps were of f
( during the 0600 conference call.
1 Reactor coolant system presstre and temperature were outside
( defined limits and reactor coolant system pressure was below the initiation setpoint of the liigh pressure Injection System during this telephone call.
k Joseph Logan, Unit 2 Superintendent, was briefed on the status of the Plant in Unit 2 control room about 0600.
Reactor coolant system pressure and temperature were outside l limits defined in Technical Specifications and Station Proce- ;
dures, and system pressure was below the initiation setpoint for 1
( the liigh Pressure Injection System while Logan was being brief ed. I
( Station Manajer, Unit 2 Superintendent, Unit 1 Operations Super-v_isort and the Reactor CooNnt System Leak l
Gary Miller, Station Manager, at.*ived at Three Mile Island about 0705. After a briefing by the Shift Supervisor and his e Managers, Miller essigned Joseph Logan, Unit 2 Superintendent,
( responsibility for compliance with procedurea and placed Michael Ross, Unit 1 Operationn Supervisor, in charge of operations directing the Shift Supervisor.
( An Operator opened the electromagnetic relief valve and block valve re-establishing the reactor coolant system leak at 0713.
An Energency Safeguards Signal was initiated twice by high
? ccactor butIding pressure following re-opening of the electro-( magnetic relief valve and block valves at 0756 and 0813.
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Operators did not operate the High Pressure Injection System
( as required by Station Procedures and Technical Specifications after initiation by the Emergency Safeguards Signal at these times.2 Later, at 1350, an Emergency Safeguards Signal was again initiated by high reactor building pressucc.
( Operators did not operate the High Pressure Injection system as required by Station Procedures and Technical Specifications at this time either.
Vice President Orders Reactor Coolant System Repressurized John Herbein, Vice President Generation, Metropolitan Edison directed Gary Miller, Three Mile Island Station Manager, to re-pressurize the reactor coolant sytem. The Vice President gave the Station Manager this order af ter discussing tt.e status of the plant and trends with the Vice president Generation, General Public Utilities about 1630.
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Reactor coolant system pressure was 650 psig at 1630. Oper-ators had depressurized the system .st 1130 in order to operate
[ the decay heat removal system. Operators had been maintaining L
low pressure by opening the cicctromagnetic relief valve and block valve or the pressurizer vent valve.
( The decision by the Vice President Generation to repres-surize the reactor coolant system was based on a recognition that reactor coolant system water and metal temperature were too
( high to allow pressure to be brought below the interloc4 for initiating decay heat removal. Without an effective means to cool down the reactor coolant system, the goal for using decay heat removal was unreachable, leaving high pressure reactor
[ coolant pump forced circulation as the only viable option.
I When the decision to repressurize the reactor coolant system L was made, the Emergency Command Team recommened continuing to attempt to establish natural circulation at low reactor coolant system pressure and control room personnel desired to remain de-( pressurized since they had regained pressurizer level.
Reactor coolant system pressure was 623 psig at 1732. The block valve for the electromagnetic relief valve was shut and
( two high pressure injection pumps were used to increase reactor coolant system pressure. Pressure was increased to 2300 psig by 1846. !
A procedure was developed for starting a reactor coolant pump, and at 1950, reactor coolant pump 1A was started and left
( running.
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Reactor coolant pump 1A was pumping reactor coolant through the reactor core and "A" steam generator and steaming to the main condenser to remove decay heat from the reactor core.
Stable plant conditions, as the Emergency Com:nand Team had defined them earlier, had finally been reached.
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NUCLEAR PLANT DESIGN Damage to the Threo Mile _ Island Reactor Core,and Nuclear Plant Design Reactor coolant pumps were pumping reactor coolant through the Three Mile Island reactor core to remove decay heat after
[- the scram at 0400. When the electromagnetic relief valve stuck open, reactor coolant was lost from the system; system pressure decreased and steam formed along the nuclear fuel rods in the reactor core. Fuel rods overheated because heat transfer is in-f efficient from a fuel rod through steam to liquid reactor cooiant.
[ O pratoro stopped all four reactor coolant pumps one hour and f orty minutes af ter the scram so reactor coolant was no longer being circulated through the core. Decay heat was not
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- removed from the reactor core, temperatures in the core ir-creasec and exceeded the melting temperature of the fuel rods.
Fuel rods and reactor core were therefore damaged. i k
Nuclear plants are designed to operate at temperatures below the melting temperatures of the nuclear fuel rods. Pressurized water reactors like Three Mile Island Unit 2, operate at high
{ pressure so there is no steam in the reactor core.
The design of a nuclear plant provides for safety systems to
(- pump or inject reactor coolant back into the system automat-ically if ecolant is lost from the system. A safety system restores reactor coolant system pressure to normal if the loss I
( of coolant is small.
l A High Pressure Injection Sytem started to pump reactor I coolant back into the reactuir cooinnt system at the outset of L the Three Mile Island accident. The High Pressure Injection System was pumping coolant back into the system to increase system pressure and condense steam in the reactor core. In-( creasing system pressure would enable reactor coolant pumps to operate and circulate reactor coolant through the core and remove decay heat.
Three Mile Ir. land Operators, Managers and Station Procedures Three Mile Island Unit 2 Station Procedure "Loss of Reactor Coolant / Reactor Coolant System Pressure" (Station Proceduce 2202-1,3) requires that the High Pressure Injection System
( operate to increase reactor coolant system pressure to at least 1640 psig, the system's initiation or actuation setpoint, as long as reactor coolant system pressure is below this setpoint.
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The Three Mile Island Primary Plant Operator did not follow this Station Proceduto after the scram, however. He shut down
, the High Pressure Injection System at 0403 oven though the pressure of the reactor coolant system was below the system's initiation setpoint.
Reactor coolant system pressure continued to decrease, and Operators shut down the reactor coolant pumps due to low reactor I coolant system pressure.
Also, Three Mile Island Managers did not direct that the Station Procedure on loss of reactor coolant be followed:
. 1. The Superintendent Technical Support did not direct I that High Pressure Injection System be operated at 0450 I
when he learned that an Operator had turned off this system.
f 2. The Station Manager did not direct that the High Pres-sure Injection System be operated when he learned about 0515 that an Operator had turned ~of f this system.
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- 3. The Superintendent Technical Support stopped reactor coolant pumps at 0541 due to low reactor coolant system pressures. He did not direct that the High Pressure
{ Injection System be operated due to low reactor coolant system pressure, however. *
( 4. Both'the Station Manager and Unit 2 Superintendent con-doned stopping reactor coolant pumps. Neither directed that the High Pressure Injection System be operated due
{ to low reactor coolant system pressure.
If the Primary Plant Operator had followed the Station Pro- ,
[ cedure on loss of reactor coolant at the outset of the acci- l
( dent, the High Pressure Injection System would have functioned I as designed and pumped reactor coolant back into the system, t Reactor coolant system pressure would have increased and steam
( in the reactor core would have condensed. Reactor coolant pumps could have continued to operate to circulate coolant through the reactor core and remove decay heat. Fuel rods would not have
( overheated and the reactor core would not have been damaged.
If Three Mile Island Managers had directed Oper ators to follow the Station Procedure on loss of reactor coolant, the
( reactor coolant system would have functioned as deaigned ano the reactor core would not have been severely damaged f 1. If the Superintendent Technical Support had directed Operators to follow Stat!.on Procedure 2202-1,3 and cpera*" the High Pressure Injection System as required
( at ( <* actor coolant would have been pumped back
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into the system and system pressure would have in-(' creased. The reactor coolant system would then have removed decay heat from the reactor core as designed.
- 2. If the Station Manager had directed the Superintendent
( T ahnical Support to follow Station Procedure 2202-1,3 and operate the High Pressure Injection System as required at 0515, reactor coolant would have been f pumped back into the system and system pressure'would have increased. The reactor coolant system would then have removed decay heat from the reactor core an de-signed.
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- 3. If the Superintendent Technical Support nad directed
[ Operators to follow Station procedure 2202-1.3 and L
operate the !!igh Pressure Injection System as required at 0514 or 0541, reactor coolant would have been pumped r back into the system and system pressure would have
( been rectored to normal. Reactor coolant pumps could then have continued to operate to circulate reactor coolant through the reactor core to prevent damage to
( the core.
- 4. If the Station Manager had directed the Superintendent Technical Support and the Operators to follow Station
( Procedure 2202-1.3 and operate the !!igh Pressure In-jection System as required at 0600, reactor coolant r would have been pumped back into the system, and system
( pressure would have been restored to normal. Reactor coolant pumps could then have been operated to pump coolant through the reactor core to remove decay heat from the core.
- 5. If the Unit 2 Superintendent had directed operators to follow Station Procedure 2202-1.3 and operate the High Pressure Injection System as required at 0600, reactor coolant would have been pumped back into the system and
(' system pressure would have been restored to normal.
( Reactor coolant pumps could then have been operated to pump coolant through the reactor coro tc emove decay heat from the core.
If Three Mile Island Operators and Managers had followed Station Procedures for operating the plant after the reactor scram at 0400 March 13, 1979, the reactor coolant system would have functioned as designed. Drcay heat would have been removed from the reactor core and the reactor core would not have been damaged.
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During the course of the accident on March 28, 1979, Three Mile Island operators and Managerc disregarded Station Procedures at these times also:
- 1. Operators blocked the Core Flood System 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> after the accident began when this safety system should have remained operational.
- 2. An Operator shut down the High Pressure Injection System after the system started automatically at 0756.
The System should have continued to operate because reactor coolant system pressure was below the system's initiation setpoint.
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- 3. An Operator did not start the High Pressure Injection System at 0919 when the system failed to start after being signaled to start by an Emergency Safeguarde Signal. The system should have been operating because reactors coolant syctem pressure was below the system's initiation setpoint.
- 4. An Operator shutdown the High Pressure Injection System after the system t. tarted automatically at 1350. The system should have continued to operate because reactor l
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coolant system pressure was below the system's initi- i ation setpoint. l 1
g 5. The Station Manager, Unit 1 Superintendent and Unit 1 I l Operations Manager condoned improper operation of the High Pressure Injection System after this safety system was signaled to start at 0756, 0819, and 1350.
( Three Mile Island Operators dicrogarded Station Procedures ,
while operating Three Mile Island Unit 2 nuclear plant during l the accident on March 28, 1979.
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Three Mile Island Managers disregarded Station Procedures l
[ and Plant Technical Specifications in directing Three Mile j l Island Operators during the accident on March 28, 1979. !
l t l tluclear Plant Desigra_ Station _ Procedures, and Plant Technical
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S pec i f i ca tTo~ n s
( A nuclear plant is designed to operate during normal oper-ations and under accident conditions so that the temperature of tha reactor core stays below thu molting temperature of the t nuclear f uel rods. Safety systens function automatically if I necessary to ensure that this design criterion is met.
Metropoliton Ediscn promulgated Three Mtle Island Unit 2 f Procedores for Operatorc to follow in operating the plant. The
( 17 IDt: 1272A/DISO:0063A
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Procedures were developed from design characteristics contained
( in the Plant's Technical Specifications. Technical Specifi-cations contein safety limits, safety system settings, limiting conditions for operating, and other design features of the plant.
Three Mile Island Unit 2 Technical Specifications stipulate that Emergency Safeguards Systems shall remain operablo, and that the liigh Pressure Injection System shall operate as de-signed to pump reactor coolant into the reactor coolant system as long as reactor coolant system pressure is below 1640 psig.2
( Technical Specifications also stipulate that Three MtJ.c Island Unit 2 shall be operated in accordance with Procedtres developed from the Technical Specifications.
Operators and Managers should follow Station Procederes ah7n operating a nuclear plant to ensure that the plant is operated in accordance with the Plant's design.
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Operating a nuclear plant in disregard of Station Procedures could result in operating the plant outside design limits and darnage the reactor core.
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{ Vice President's Orderr Control of Three Mile Island __ Unit 2 is Regained p The Station Manager directed that the reactor coolant system t be repressurized following an order given him by the Vice President, Generation, Metropolitan Edison about. 1630.
( Actions taken by operators following this order conform with Plant Technical Specifications and Station Procedures.
The block valve for the electromagnetic relief valve was
(- shut. This valve (or the electromagnetic relief valve) was required to be shut by Plant Technical Specifications and Sta-tion Procedures.
Two !!igh Pressure Injection Pumps were operated to increase reactor coolant system pressure to 2300 psig. These pumps were
( required to be operating by Station Procedure 2202-1,3 to in-crease reactor coolant system pressure to at least 1640 psig. !
Reactor coolant pump 1A was started and run to circulate
( reactor coolant through the reactor core to remove decay heat l rom the core.
( This mode .2f decay heat removal sas required by Station Procedure 2102,3.3 and Technical Specifications until reactor coolan: system temperature and pressure decreased to the range
( ot the decay heat removal system.
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i'- . of Three Mile. Island Unit 2 was regained about 1950
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.a .w or coolant pump 1A was pumping reactor coolant through
( a .or core and "A" steam generatcr and steaming.to the mai A denser to remove decay heat from the reactor core.
Thus Operatoro operated Three Mile Island Unit 2 in confor-mance with Plant Technical 3pecifications and Station Procedures in carrying out the Vice President's order, and control of Three
( Mile Island Unit 2 nuclear plant was regained.
( Consequences of Jisregarding Station Procedures and Plant Tecnnical Soec Gicationc Three Mile Island Unit 2 was operated without regard to Station Procedures and Plant Technical Specifications during the eccident on March 28, 1979 and the reactor core was severely damaged.
The consequences of operating Three Mile Island Unit 2 while disregarding Station Procedures and Plant Technical Specifica-tions are:
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- 1. The plant must be decontaminated. The cost of decon-
[ taminating tne plant is nstimated to be one billion l
dollars.
- 2. The cost to restore the plant to an operational condi-( tion is estimated to exceed $2(0 million.
- 3. Three Mile Island Unit 2 is shut down for an indeter-( minable number of yearc.
- 4. Three Mile ILland Unit 1 has not operated aince tae Unit 2 accident.
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If Three Mile Island Operators and Managers nad followed Station Procedures and Plant Technical Specifications after the reactor scram at 0400 March 28, 1979, the reactor coolant system I would have functioned as designed. Decay heat woald nave been l removea from the reactor core and the rocctor cote would not i
( have been damaged. I Authority of a Nuclear Power Plant's Technical Soecification
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The tiuclear Regulatcry Commiosion issues an Operating Li-censo to a Utility to pertit the Utility to operate a nucl.:ar
( po.er plant as a ccmnercial facility. Technical Specifications, written 'y o the Utility operating the plant, are a part of the Unit Operating License.
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The Nuclear Regulatory Commission issues an Operating Li-conse by authority of Congress. Therefore, Technical Specifi-( cations and Station Procedures derived from the Technical Speci-fications, are Rules to be followed by all Utility personnel r' .
responsible for a nuclear plant - Executives, Managers, and L Operators.
( Turning Off High Pressure Injection and Pressurizer Level The Three Mile Island Primary Plant Operator turned off the High Pressure Injection System at the outset of the accident on
( . March'28, 1979. Reactor coolant system pressure wat below tne operating range, decreasing, when the Operator started turning
[ off the High Pressure Injection by turning off the Emergency L Safeguards Signal. The pressurizer was less than two-thirds full .
( The reactor coolant nyatem was not going solid and system conditions did not indicate that the reactor coolant system was going solid when the Operator turned off the High Pressure In-j ection System at the outset of the Three Mile Island accident.
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The Three Mile Island Operator turned off the High Pressure r Injection System at the outset of the accident on L March 23, 1979, because he had been instructed to do so. Tnree Mile Island Operators were instructed by the Training Staff to torn off tne High Pressure Injection System pecaptly after ini-( tiation following a reactor scram, to prevent pumping sodium hydroxide into the reactor coolant system. The High Pressure Injection System had pumped sodiu;a hydroxidt into the reactor coolant system in the past and this required extra outage time
( to prepare the plant to resume operations. Operators were in-structed, thererote, to shut down the High Pressure Injection System to prevent an extended plant outage.
One year before the accident, on March 29, 1978, a Three Mile Island Operator turned off the High Pressure Injection
( System to prevent pumping sodium hydroxide into the reactor coolant system. An Emergency Safeguards Signal, initiated by low reactor coolant system pressure following a reactor scram, had started the High Pressure Injection System. The High Pressure Injecticn System was turned off even though reactor coalant system pressure was below 1640 psig. Reactor coolant system pressure remained below normal for acout one hour.
The reactor cadant cyatem wac not going colid duitng *,he Three Mile Islana accident. Reactot coolant system precsure was
( below normal from 0302 until after the block valve for the elec-tromagnetic relief valve was closed st 0618. Pressure was below normal most of the time from 0724 to 0924 and tnroughout tne t ime 114 ') to 1330.
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When the Superintendent Technical Support learned about 0450, that High Pressure Injection had been turned off, reactor ,
coolant system pressure was 1060 psig. Pressurizer level was .
380 inches (full is 400 inches) and had'been steady at this level for about 30 minutes.
When the Station Manager learned, during his 0515 telephone call, that High Pressure Injection had been turned off, reactor coolant system pressure was less than 1100 psig. Pressurizer level was changing. Level was 390 inches at 0515, 375 inches at 0524, 390 inches at 0530; and 360 inches at 0536.
When the Suprintendent Technical support stopped reactor coolant pumps at 0511, reactor coolant system pressure was 102^
psig. Pressurizer level was 360 inches and decreasing.
When the Station Manager learned, during his 0600 conference call, that reactor coolant pumps had been stopped; reactor
- l coolant system precsure was below 900 psig. Pressurite level was 350 inches at 0600. The level decreased to 290 inches at 0530.
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ERRORS AT THREE MILE ISLAND Primary Plant Operator's, Error
( The Three Mile Island Primary Plant Operator shut down the High Pressure Injection System following the reactvr scram at 0400 March 23, 1979. 't
( Shutting down the High Pressure Injection System was wrong because coolant necessary for removal of decay heat from the reactor core was being pumped into the reac'.or coolant system by l the 31gh Pressure Injection System.
The Prinary Plant Operator should have vetified that the l High Pressuring Injection System was operating as required by Station Procedure 2202-1.3.
The Primary Plant Operator shut down the High Pressure In-jection .9yatem because the Training Department instructed Operators to shut this system down promptly i', the system started following a reactor scram.
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A Primary Plant Op.:rator had followed these inst uction
[ before - on March 29, 1978, the High Pecasure Injection System, l which had been initiated by low reactor coolant system precsure fo?. lowing a reactor scram, was shut down. Reactor coolant system pressure was below normal for about 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> but the High f Pressure Injection System was not operated.
This error in operating the High Pressure Injection System was not corrected. Either (1) Managere at Three Mile Island
[ responsible for correcting the error did not change the instructions given the Primary Plant Operator, Shitt Supervisor and other Operators on chitt on March 28, 1979 or (2) Station
{ Management did not change the instructions given any Operators.
( Other Operator Errors Three Mile Island Operators also made these errors:
( l. Operators made tne cort flood syctem inoperable at 0600.
The core flood syLtem 13 designed to be operable to inject
[ coolant into the reactor coolant Lystem if coolant is lost from the systen and pressure decreases to 600 psig. Making this sys-tem inoperable while the nuclear plant was operating was wrong.
Operators should have maintained tne core flood system in an operable status at 0600.
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- 2. An Operator opened the block valve and electromagnetic ,
relief valve at 0713. Operator opened these valves -
f requenti;' between 0713 and 1732.
Operators were wrong in opening the blocr valve and electro--
( magnetic relief valve because oposiing these valveu caisses coolant to be lost from the reactor coolant system.
Operators should have kept the block valve closed after is
{ was closed at 0618.
t 3. The Operator shut down the liigh Pressuro Injection i Sydtem at 0317.
Shutting down the !!igh Pressure Injection System at 0817 was
[ wrong because coolant needed to remove decay heat from the react.or core was being pumped into the reactor coolant system.
The Operator should have allowed the fligh Pressure Injection
{ System to operate at 0817.
- 4. The Operator did not start the !!igh Pressure Injection l System at 0319.
tiot starting the fligh Pressuring Injection System at 0819
[ was wrong because the system did not start when sign aleri and the reactor coolant System needed coolant to re.Tove decay heat from the reactor core, c
( The Opwrator should have started the High Pressure Injection System at 0319.
- 5. *he Operator shut uown the !!igh Pressure Injection ,
Jystem 1351.
Shutting down the !!igh Pressure I.ijection Gyatem at 1351 was wrong because coolant needed to remove decay heat frce the reactor core was being pumped into the reactor coolant system.
The Operator should have verified that the High Precsure Injection Syctem was operating properly at 1351.
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Errors - Sooerintendent Technica?_ Support
( l. Superintendent Technical Support's First Error:
The Superintendent Technic 3'. Support accepted plant condi-( tions at Three Mile Island Unit 2 when he arrived in the control room about 0450.
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The Superintendent Technical Support accepted plant condi-tions at 0450, even though (1) he recognized an unusual situ-ation; (2) he was told that High Pressure Injection had been shut down f ollowing the 0400 scram; (3) the Shift Supervisor was not in the control room at 0450 and had been away since 0415.
k The Superintendent Technical Support should have directed the Primary Plant Operator to operate the High Pressure Injec-tion System at-0450.
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- 2. Superintendent Technical Support's Second Error:
The Superintendent Technical Support concurred with the Shift Supervisor in shutting down reactor coolant pumps and relying on natural circulation to cool'the reactor core.
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The Superintendent Technical Support concurred with shutting down reactor coolant pumps even though: (1) he reviwed the Heat
( Up/Cooldown Curve which shows temperature and pressure limita-tions f or operating reactor coolant system pumps and going to natural circulation; (2) reactor coolant system pressure was below the initiation setpoint of the High Pressure Injection
[ System as well as below minimem pressure for operating reactor coolant pumps; (3) reactor coolant system pressure and temper-f ature were outside limits for natural circulation.
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The Superintendent Technical Support should have directed the Shift Supervisor to operate the High Pressure Injectio.1 Syst.em instead of shutting down the reactor coolant pumps.
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Errors - Station Manager _
- l. Station Manager's First Error:
( The Station Manager accepted conditions at Three Mile Island.
Unit 2 at 0515 March 28, 1979.
[ The Station Manager accepted conditions at Three Mile Island Unit 2 at 0515 even though: (1) he learned during a telephone call at this time that the High Pres 3ure Injection Syste.m had been shut down following the 0400 scram; (2) he was disturbed
[ ' bout plant conditions.
During the 0515 telephone call, the Station Manager should l have directed the Superintendent Technical Support to operate ;
.- the High Pressure Injection System, l
- 2. Station Manager's Second Error:
The Station Manager accepted conditions at Three Mile Island Unit 2 at 0600.
{
24 ID4:1272A/ DISC:0068A
[
( . .. . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __
.d. .
I' L
The Station Manager accepted conditions at Three Mile Island
[ Unic 2 at 0600 even though: (1) he was told during a telephone L call at this time that reactor coolant pumps were stopped; (2) he knew this_was abnormal and that focced circulation of reactor coolant-must be reestablished.
[
During the 0600 telephone call., the Station Manager should have directed the Superintendent Technical Support to operate
(' the High Pressure Injection System.
- 3. Station Manager's Third Error:
The Station Manager accepted the mode of operating Three Mile Island Unit 2 which had prevailed since 0400 after his arrival in the control room at 0705.
[
The Station Manager accepted the mode of operating Three Mile Island Unit 2 at 0705 even though: (1) fuel failures had occurred; (2) there was no circulation of reactor coolant
( through the reactor core.
[ The Station Manager should have changed the manner in which L the three Mile Islr ' Unit 2 reactor plant was being operated after his arrival . the plant at 0705.
Errors - Unit 2 Superinter"'ent Unit 2 Superintendent's First Error:
( l.
Pba Unit 2 Superintendent accepted plant conditions at Threc Mile Island Unit 2 at 0545.
{
The Unit 2 Superintendent accepted plant conditions at Three Mile Island Unit 1 at 0545 over; though: (1) he came to the plant because he knew the 0400 reactor scram was abnormal; (2) reactor coolant pumps were stopped and there was no circulation of coolant through the reactoc core; (3) reactor coolant system
( pressure was below t.he initiation setpoint of the High Pressure Injection System, but the system was not on, having been turned off by an Operator.
Af ter being br' Med on plant conditions in the Three Mile 1
Island Unit 2 cor.tro' room about 0545, the Unit 2 Super'.ntendent should have dir -," nd tha Shif t Supervisor to opera'.e the H!)h
(
Pressure Injecs a System.
- 2. Unit 2 Superintendent's Second Error:
[ The Unit 2 Superintendent, at 0715, continued the mode of operating Three Mile 'sland Unit 2 which had prevailed since the
, scram at 0400.
25 ID#: 1272A/ DISC:0068A L
The Unit 2 Superintendent continued the mode of operating Three Mile Island Unit 2 at 0715 even though: (1) fuel failures had occurred; (2) the Station Manager assigned him responai-bility for verifying that personnel complied with procedures.
The Unit 2 Superintendent should have changed the manner in which Three Mile Icland Unit 2 was being operated at 0715.
I l
Error - Unit 1 Operations Supervisor U7it 1 Operations Supervisor's Error:
The Unit 1 Operations Supervisor , at 0715, continued the r mode of operating Three Mile Icland Unit 2 which had prevailed
[ since the scram at 0400.
The Unit 1 Operations Supervisor, continued the mode of
( operatil.g Three Mile Island Unit 2 at 0715 even though: (1) tuel failures had occurred: (2) no coolant was being circulated through the reactor core, and coolant had r.ot been circulated through .he corc since reactor coolant pumps were stopped; (3)
[
the Station Manager assigned him responsibility for operating the plant and directing the Shift Supervisor.
[ The Unit 1 Operations Supervisor should have changed the manner in which Three Mile Island Unit 2 was bei ng operated at 0715.
Action br_Vice President Generation, Metronolitan Edison L
The Vice president Generction, Metropolitan Edison, directed the Station Manager to represcurize the reactor coolant system sometime af ter 1630.
[
L The Vice Preeident Generation, Metropolitan Edicon, directed that the reactor coolt .t system he repressurized because:
- 1. The prec are and temperature of the reactor coolant system exceeded the design .-pecifications of the iecay heat removal system and the decay heat removal ayatem could not function.
- 2. Circulating reactor coolant through the reactor core
[ and steam generator by a reactor coolant pump with reactct caolant systom preaJure at operating levela *;as the deaign method of removing decay heat frca the
( reactor core during the first stage of a reactor cooldown.
26 ID4 : 12 7 2 A/ DISC : 0 0 6 d A
{ - - - - - - -
The Station Manager followed the Vice President's order and:
- 1. The block valve for the electromagnetic relief valve was shut;
- 2. The High Pressure Injection System was operated to increrse reactor coolant system pressure to 2300 psig;
- 3. Reactor coolant pump 1A was started;
- 4. Reactor coolant was circulated through the reactor core
[ and steam generator to remove decay heat frcm the L reactor core;
- 5. Stable plant conditions were finally reached.
When the orders of the Vice President Generation were
( carried out:
- 1. Attempts to use the decay heat removal system in a situation when the system was not designed to operate
{ were terminated.
- 2. The High Pressure Injection System ,tas used as designed to return coolant to the reactor coolant system and increase system pressure.
- 3. The reactor coolant system was operated as designed during the first stage of a reactor cooldown - reactor cool an t pump circulating reactor coolant through the reactor core and a steam generator to remove decay heat.
[
In following the Vice President Generation, Metropolitan Edison directive, the Station Manager changed the mode of oper-ating Three Mile Island Unit 2 that had prevailed since 0400 by directing that Three Mile Island Operators operate the Three Mile Island reactor plant as designed rather than as determined by the Operator.
[
[
[
27 ID4:1272A/ DISC:0063A
L A CORRECTIVE ACTION PROGRAM r
L Causes of Operator Errors and Corrective Action Primacy Plant Operator's Error - Shutting Down the High Pressure Injection System at 0403
( When the Primary Plant Operator shut down the High Pressure Inj ection System at 0403 on March 28, 1979, he followed instructions of the Three Mile Island Training Department. The same instructions were followed by the Primary Plant Operator
[ wnen he shut down the High Pressure Injection System en March 29, 1978, one year before.
[ Tne Station Manager, Unit 2 Superintendent, Superintendent Technical Support, and Unit 1 Operations Manager, accepted the Operator's snutting down the High Pressure Injection System on
( March 28, 1979. The Station Manager, indicated during his 0515 telephone call with the Station, that he expected the High Pressure Injection System to be handled like this.
The High Pressure Injection was operating as designed when shut down on 0403 March 23, 1979. Coolant was being pumped back into the reactor coolant system to increase system pressure.
Adding coolant to the system and increasing system pressure would enable reactor coolant pumps to circulate ecolant through the reactor core to remove decay neat and preveat damage to the Core.
Shutting down the High Pressure Injection System at 0403 March 23, 1979 caused damage to the reactor core b 2cause coole.at lost from the reactor coolant system was not replaced. System pressure decreased and steam formed along the fuel rods causing the fuel rods to overheat. Reactor coolant pumps were then shut
_ down due to low reactor coolant cyctem pressure. Coolant .cas no longer circulating through the reactor core to remove decay neat, and core damage resulted.
Shutting ocwn the High Pressure 7.njection System at 0403, Maren 23 1979, was contrary tu design. Operating the High Preasure In.)ection Systen contrary to deaign resulted in
{ damaging the reactor core.
Tne Three Mile Ialand Primary Plant Operator snut cown tne
[ High Prosaure Injection System following the reactor scram at 0400 Marca 23 197) becaune:
f 1. Operatorc were instructed to operate the System thia uay.>
- 2. Managera ugucted Operators to opurate che symtem, thia
{ way to get tae p;.e e r t>lant nac, on line promptly.?
28 ID9: 126SAfDISC4:006dA
( - - ---- _- - - - -- - - - - - - - ----- - -
- 3. Managers did not expect Operators to allow the High l Pressure Injectio;. System to operate if started following a reactor scram because this had caused Unit down time in the past.3 t
- 4. Operators were used to operating tais way because of the attitude toward Technical Specifications of Vice-President Generation, Metropolitan Edison; Managers at Three Mile Island; and Shift Supervisors at Three Mile Island.
- 5. Three Mile Island Operatore were not held accountable for their actions by Managers at the Station or any other person in authority.
Corrective Action For Primary Plant Operator's Error - Shutting Down the High Pressure Injection Systen at 0403:
- 1. Change instructions to all Operators regarding oper-ation of the High Pressure Injection System. Tell them to operate the High Pressure Injection System as re-quired by Station Procedure 2202.1-3.
[
- 2. Institute a follow-up corrective action program at L Three Mile Island with the objective of ensuring that an error like shutting down the High Pressure Injection System on March 29, 1978 is identified, cause determined
[ and corrective action implemented.
- 3. Snow all Metropolitan Edison and and Tnree Mile Ialand
[
Officials and Managers with authority over the oper-ation of Three Mile Islend, tnat operating Three Mile Island nuclear plant in accordance with design ia the economical way to operate. Tne cost of operating Three Mile Island Unit 2 contrary to design on March 23, 1979 is a gcod example to use.
- 4. Change the attitude of Metropolitan Edicon Corporate officialJ and Manager: and Shift Supervisors at Three Mile Island, toward Technical Specifications. Show them that tney are re;ponsible for Tncee Mile Island Technical Specificiations and tnat fol. lowing Technical Specifications then operating a nuclear p'. a n t will re-cult i rt operating tne plant in accordance wito design.
- 5. Require that e ersono in authority at Metropolitan Edison, tho Three Mile Island Plant and the Nuclear
[ Regulatory Commi;3 ion, take action against a Three Mile Island Operator wno does not follow a Station Ptocedure when following tne Proceaure u within his compctney,
( and tne Station Manager ..a a directed that t. b e P r o c e d u r '-
he t u u ma .
- 2) !D4126.ia/DLSC':CuadA t -
Proof of Corrective Action
(
The Three Mile Island Primary Plant Operator would have
[ verified that the High Pressure Injection Syste:a was operating L as required by Station Procedure 2202-1.3 instead of shutting the system down following the reactor scram at 0400 March 28, 1979, if:
L
- 1. The error by the Operator on March 29, 1978 had been corrected and all Operators had be<_n told to follow Station Procedure 2202-1.3 when operating the High Pressure Injection System.
[ 2. The Operator on March 23, 1979 knew that his Shift L Supervisor expected him to operate the System in accordance with the Station Procedure.
r L 3. The Opetator on March 23, 1979 knew that Metropolitan Edison Corporate Officials, and Managers at Three Mile Island expected him to follow Station Procedures in operating the system.
- 4. The Operator on March 29, 1979 Knew that he would lose
~
his Operator's license, his position at Three Mile
. Island and his job, if he did not follow this Station Procedure.
Operators Making the Core Flood System Inoperable Operators made the core ficod system inoperable to pre /ent the edditicn oE reactor coolant to the reactor coolant system.
The preasuriner relief system ,arotects the reactor coolant system frca damage by exceanive pres:ure. Making the core fl. cod system inoperable was not nececcary to prevent damage to the reactor Coolan'. 'yStem.
( Operating the reactor plant without the core flood system u contrary to design.
Operatoru .aade tne core flood aystem inoperable at 0600
[ becauce:
- 1. Tne tnuugnt this .v a s the right thing to ca.
- 2. Three Mile IJland Operators were not held accountable tor tneir actions by Managers at the 3tation or any other peruana in autnority.
(
30 ID4: I N a t,f D I .;L : 00uJA
( - - - - - - - - - - -- - - - - - - - - - - - - -
F Correccive Action for Operators' Making The Core Flood System L Inoperable:
~ 1. Remind all Three Mile Island Operators that Three Mile L Island is designed to operate without damaging the reactor core; therefore the plant must be operated in accordance with design or risk damaging the reactor core.
{
- 2. Remind Operators that operating Three Mile Island in accordance with the Plant's Technical Specifications
[ and Station Procedures will result in operating the plant in accordance with design.
( 3. Tell each Three Mile Island Operator that Metropolitan ,
Edison's Policy is to operate Three Mile Island in accordance with design; therefore, Three Mile Island is
[ to be operated in accordance with Technical Specifi-cations and Station Procedures.
- 4. Require that persons in authority at Metropolitan Edison, the Three Mile Island Plant and tne Nuclear Regulatory Commission, take action against Three Mile f Island Operarors who do not follow a Station Procedure
[ when following the Procedure is within their competency and the Station Manager has directed that the Procedure be followed.
Proof of Corrective Action Three Mile Island Operators would have maintained the Core Flood System in operating condition at 0600 March 23, 1979, it:
- 1. Each Operator had remembered that operating a Three Mile Ialand reactor plant system contrary to the
- i. system's dasign riaks damaging the reactor core.
- c. r,ach Operator knew that the Policy of Metropolitan Edison and the Station was to operate the Three Mile Island in accordance with Technical Specifications and
[ Station Procedures.
- 3. Ec.cn Operator knew he would lose his Operator's
[ License, his position at Three Mile Island and hia job, if he did not follow Station Procedures.
[
31 ID4:126dAfDISC:0060A c --- ---
L Operators Opening the Block Valve and Electromagnetic Relief
{ Valve at 0713 c Operators were attempting to control reactor coolant system L pressure and pressurize level when the block valve and electro-magnetic relief valve were opened at 0713.
Opening the block valve and electromagnetic relief valve
. caused coolant to be lost from the reactor coolant system. 1 Lasing coolant reduced the system's capability to remove decay heat from the reactor core, and damage to the reactor core increased.
The pressurizer relief system is designed to relieve reactor
[ coolant system pressure automatically before system pressure reaches the design limit in order to prevent structural damage.
The block valve ano electromagnetic relief valve are a part of
( the pressurizer relief system.
The pressurizer relief system v 4 3 being operated contrary to the system's design when Operators were attempting to control
{ reactor coolant system pressure and pressurizer level with the System.
Operating the pressurizer relief system contrary to design increased damage to the reactor core.
( Operators opened the b3ock valve and electromagnetic relief valve at 0713 because:
- l. They Nere attempting to control reactor coolant system
{ pressure and pressurizer level.
- 2. fhey thougnt tnis was the right tning to do.
- 3. Three Mile Island Operators were not held accountable for t h e l. r actions by Managera at the Station or any
( other persona in authority.
Corrective Action for Operators Opening the Bloc < Valve and
{ Electromagnetic Relief Va l s/ e at 0713:
- 1. Remind all rhree Mile Island Opurators that reactor
[ plant sjatems are to be operated in accordance with aediga because sy a te ,a are designed to prevent damage to th> reactor core. Remind them that operating sys*. ems a ntrary to desten
( rissa damaging the reactor core.
[
32 ID9: 126dA/DI50:0064A
( - _ - - - - - - - -
P L
- 2. Remind all operators that (1) operating Three Mile
{. Island in accordance with Technical Specifications and Station Procedures will result in operating the plant.in accordance with p design; (2) operating contrary to Technical Specifications and L Station Procedures risks damaging the reactor core.
- 3. Tell each Three Mi3e Island Operator that Metropolitan
( Edison's Policy is to operate Three Mile Island in accordance with design; therefore, Three Mile Island is to be operated in accordance with the Tec".nical Specifications and Station Procedures.
{
- 4. Require that persons in authority at Metropolitan Edison, the Three Mile Island Plant, and the Nuclear Regul atory
[ Commission, take action against Three Mile Island Operators who operate a Three Mile System in a manner not outlined in a Station Procedure.
Proof of Corrective Action Three Mile Island Operators would have kept the block valve closed at 0713, after it was closed at 0618, if:
k 1. Each Operator had remembered that Three Mile Island reactor plant systems were designed to prevent damage to the reactor core and operating a system contrary to
( design risks damaging the reactor core.
- 2. Each Operator knew that the Policy of Metropolitan Edison and the Station was to operate Three Mile Island
( in accordance with Technical Specifications and Station Procedures.
- 3. Each Operator knew he would lose his Operator's license, his position at Three Mile Island, and his job if he operated a Three Mile Island Syste.1 in a manner
( not outlined by a Station Procedure.
[
Operators Opening the Block Valve and Electromagnetic Relief Valve Between 1130 and 1732
{
Operators were depressurizing the reactor coolant system to operate the decay heat removal system when they opened the block
[ valve and electromagnetic relief valve between 1130 and 1732.
Opening the block and electromagnetic relief valve between 1130 and 1732, caused coolant to be lost from the reactor
( coolant system increasing damage to the reactor core.
( 33 104: 126aA/ DISC:0068A f _ . . _ . _
Depressurizing the reactor coolant system at any time L between 1130 and 1732 vould not etable the decay heat removal system to operate becaase reactor coclant system pressure and r temperature ware above the design limit of the decay heat
[ removal system.
The pressurizer relief system was being operated contrary to design when Operators opened the block valve and electromagnetic
{ relief valve to a t t e m p t. to operate the decay heat removal system between 1130 and 1732.
Operating the pressurizer relief system contrary to design increased damage to the reactor core.
( Operators opened the block valve and pressurizer relief valve between 1130 and 1732 because:
{
- l. They wanted to depressurize the reactor coolant system in order to start the decay heat removal system.
- 2. Tney thought this was the right thing to do.
- 3. Three Mile Island Operators were not held accountable for their actions by Managers at the Station or other
( petsons in authority.
Corrective Action for Operators Openin; t .e Block Valve and Electromagnetic Relief Valve Between .
4 and 1732:
- 1. Remind all Three Mile Island Operators that reactor plant
[ systems are to be operated in accordance with design because systems are designed to prevent damage to the reactor core, f Remind tnem that operating systeas contrary to design risks
( damaging the reactot core.
- 2. Remind all Operators that plant e/olutione such aa - plant cool doen, are te he performed as outlined in 9tation Pro-( cedures so that the evolution ia : ::r f or med in accordance with design.
- 3. Tell each Three Mile Island Operator that 'detropolitan Edison's Policy is to operatu Thre2 Mile Island in accordance with design; therefore, Three Mile Ialand is tu
-( be operated in accordance with the Plant'3 Technnical Specifications and Station Proce!utea.
- 4. Require that persona in aathority at Metropolitan Odiaan,
{ the Three Mile Island plant, and the tiuclea: 7egu atory Commission taku action against Three '4ile Ialand Opetator; who :,erf.orn a plant oper_; ion auua c. a a plant ;ool d ya n ,
[ Contrary to the StatiJn PrQueluce.
( 34 10 : 1.26 A. J I : J : 0 0 6 3.i
( - - - - - - - - - - --
a .
m Proof of Corrective Action Taree Mile Island Operators would have kept the block valve closed between 1130 and 1732, after it was closed at P618, if:
- 1. Each Operator had remembered that a plznt opecation such as a plant cool down, is to be conducted is outlined in the
[ Station Procedure to ensure tha: the operation is conducted as designed; and operating a system contrary to design risks damaging the reactor core.
- 2. Each Operator knea that the Policy of Metropolitan Edison and the Station was to operate Three Mile Island in ac-cordance with Station Procedurec.
- 3. Each Operator knew he would lose his Operator's license, his pocition at Three Mile Icland, and his job if he performed a
[ plant operation such ao a plant cool down, in a manner different than outlined in Station Procedures.
~
Operator Shutting Down the High Preasure Injection System at 0817 The High Pressure Injection System started autcmatically at 0756 aignaled by high reactor building precsure. High reactor
( building preasure ia a dif f erent abnormal condition than the condition which started the High Precaure Injection Syctem at 0400.
The Operator shut down the High Preaaure Injection djatem at 03,,/ .
v1 .
The High Preaaure Injectinn Sycte wac operating as accigned at 0817 - pumping coolant back into the ceactoc coolant a y a t ea.
to increase Listem capacity to remove ; cay heat trea the r e d C t o :. Cor2.
Shutting dovin the High P:e n ure Injection Sys'.em at 0817 was contrary to syatem design.
Shutting down tae High Prea;ura Injection Jy; tam at 0317 re-aulted ic incroaced dcaage to the reactar core.
The Operator snut down the High Prec;urc Injection Systen at 0317 becauce:
[
- 1. The Gyatem hc.d been ; >;u t : m.i n t e f o r t_ .
- 2. Three Mile Island Opstator. .ere ;ot neld accDun'able
( m taen actions am m m + m, x ,,y other p e : J a n ., in autnerit;.
35 ID4: 1 J G 5.\/ D I . s :0063.\
[ _ - _ _ - - _ _-- - - - - - -
Operator Not Starting the High Pressure Injection System at 0319 The Iligh Pressure Injection Syster did not start at 0819
_ when signaled to start again by high reactor building pressure.
The Sysuem did not start because the System was not lined up properly.
The Operator did not start the High Pressure Injection System at 0819.
The reactor coolant system was below deaign operating pressure at 0819, due to the loss of coolant from the system, so not starting the High Pressure Injection System at 0819 meant
[ the System did not operate as designed.
Operating the High Pressure Injection System contrary to
( design at 0819 increased damage to the reactor core.
The Operator did not start the High Presuure Injection System at 0819 because:
{
- 1. The System had been chut down before when started.
[ 2. Three Mile Island Operators were not held accountable for their actions by Managers at the Station or any other persons in authority.
Operator Shutting Down the High Presauce Injection System at 1351 The High Pressure Injection System was started again by hign reactor building pressure at 1350.
The Operator shut d yan the Jigh Prcasare Injection Syatea at 1351.
The reactor coolant ayatem wac b ._ l va dealgn operating pte33ure at 1351 due to loss of coolant.
Shutting down the High Pro.sare Injection Syster, at 1351 was contrary to design.
[ Oper ating tne High Preamatt Injuation 3y, tem contrary to design at 1351 increaael th. damage to the reactor care.
Tne Operator shut down the high Pre ;uru Tjection Systen at 1351 becaulo:
(
36 IDJ: 1.7 5 3.1/ D I S C : 0 0 0 3 ,i
{ - - - - - -
l I
L
- 1. The System had been shut down before.
- 2. Three Mile Island Operators were not held accountable for their actions by Managers at the Station or any other persons in authority.
Corrective Action for Operators' Shutting Down the High Pressure Inj ectian System at 0819, and 1351 and 1:ot Starting the System at 0319; Proof of Corrective Action:
The Tnree Mile Island Operators would have allowed the High Pressure Injection Systen to operate at 0317 and 1351, and .sould have started die High Pressure Injection System at 0319, if:
- 1. The error by the Operator on March 29, 1978 had been
( corrected and all Operators had been told to follow Station Procedure 2202-1.3 when operating the High Pressure Injection System.
- 2. Each Operator knew that the Shift Supervisor expected him to follow Station Procedure 2202-1.3 in operating the High Pressure Injection System.
- 3. Eacn Operator knew that he would lose hin Operator's license, his position at Three Mile Island and his job if he did not follow this Station Procedure.
Caucec of Managers' Errors and Corrective Action Superintendent Technical Support's First Error The Superir.tNdent Technical Support knew that there wac a
( aerious problem in the Unit ? teactor plant ;oon after nis arrival in the Control Roc:a at 0450. He promptly directed that tun or more tecnnical and operations persannel be called to the Station. (The Unit Two Operations Engineer was calle.i at
( 0501). The Superintendent rechnical Support did nothing to change plant conditions, ho;/e v a r . He accepred plant condition; after h i .; arci/al in the Control Room at 0450.
The Superintendent Technical Support accepted :' h r e e '4 i l '.
Islana Unit 2 plant conditions at 0450 m;Tuce:
( 1. ne mm not e m ed m toe ch m e ana ,ive xdm te Operatora.
37 ID : 1 t 3 Ac J :SC : ] x is
( _ _ - - - - - - - -
- t ,.
r L
- 2. Even though he, knew there was a serious problem in the plant, he was~under no obligation to ensure that proper action was taken.
( 3. He was not : accountable 'to the ' Station Manager or any other authority for proper operation of the plant.
( 4. Turning off High Pressure Injection wnen activated following a reactor scram had1been accepted before at Three Mile Island.
(
Cor';e:tive Action for Superintendent Technical Support's First Error:
- 1. Make the "duty section head" (when he is present at the
, s t a ti on', , responsible for proper operation of the plant and accountable to the Station Manager.
- 2. Give the "duty cection head" (when he is present at the station), authority over the Shift Supervisor and other l' ,
personnel assigned to operate the plant.
r 3. Instruct all persons at Three Mila Island who are
( assigned as "duty section head", that Station Procedure 2202-1.3 is to be followed in operating the High Pressure Injection System.
4.
Institute a follow up corrective action program at Three Mile Island; purpose - to ensure that an error like shutting down the High Pressure Injection System
( on March 29, 1978, is identified, cause determined, and corrective action implemented.
Ef f ectiveness of Corrective Action It is possible that the Superintendent Technical Support, as "duty section head", would have directed the Primary Plant Operator to operate the High Pressure Injection System at 0450,
[ after he arrived in the Unit 2 Control Rcom from home, if:
- 1. He had assuned responsibility for proper operation of
[ the plant upon arrival; was accountable to the Station Manager for proper operation of the plant; and had authority to direct Operators operating the plant.
( 2. He had been told to ensure tha* the High Pressure Injection System Ja operated as required by Station Procedure 2202-1.3 as a part of the corrective action
( program resulting from the March 29, 1973, shut down of the System.
[ 33 IDi: 1263A/ DISC:0068A L
r It is also possible that the Superintendent Technical L Support would not have ordered the Primary Plant Operator to operatt the High Pressure Injection System when he arrived in the Three Mile Island Unit 2 Control Rccm from his ho'e at 0450
( because of the amount and detail of ir. formation to be assimilat-cd.
At 0450, conditions were abnormal throughout the Three Mile
[ Island Unit 2 nuclear plant. Conditions were abnormal in: the reactor core, the reactor coolant system, the pressurizer relief system, the reactor building drain tank, the reactor building
( sump, the reactor building atmosphere, and the condensate system. Conditions were also abnormal in the Auxiliary Building. Alarms were indicating many of the a tanor m a l
( conditions.
At 0450, the Shift Supervisor was working to fulfill hic
( responsibility to get the plant back on line generating electricity as soon as possible. He returned to the Control Room at 0500, having been away since 0415.
- l. t 0500 the Shift Supervisor had not yet recognized that there was a serious problem in the Three Mile Island Unit 2 reactor plant. He nad not recognized that there was a serious
( problem in the reactor plant because he had not been in the Contral Room to see plant instruments and hear alarms. Plant intruments and alarms vote indicating a cerious problem in the plant.
( He had been away from the Control noom for 45 minutea during the first haur of the accident because hia duties required that he ,to r k in the I' u r b i n e Building to rectify the problem in the condensate systen so the plant coald be returned
[ to service and generate pcwer.
Superintendent Technical Sapport'n S:.cend Error The Superinten ant Technical Support concurred , tith the Shift Supervizor's acciaion to 7 hut dan reactor coolant p r p3.
Tne S upe r i n t e nt'en t Technical ,J,jort concurred with the Sh u t S ug e .,1.w a dec w _ m ahut ~, rm m c, >unt gm and relf CD natu;al Cit:UlatiGn to Cool the 'l e a c t o r Gore W C,tu?- :
- 1. He did ntt aave sufficiect t ir " to evaluate the Shift Supervi:or'3 deciaiun to ; op reactar calant e mpu do.
to punp vtDrat.iUI^..
- 2. He wan uneer aa calig nien ta t a 'v t i .y ta ensato that a prop.. m e:, :t u m ^ ;Je.
{
- a. ac - - n-~ - , - h m .u ~.a a dhlf0 j d ,' !L / i a 'r.
" " ' ~ ~
( - - - - - - - --
e.=
[ 4. It was the practice of Managers at Three Mile Island to L
accept the actions of Operatocc operating the plant.
- 5. He was busy doing other things.
Correcti ve Action for Superintendent Technical Support's Second
( Error:
- 1. Make the "duty section head" responsible for proper operation of the plant.
(
- 2. Station the "duty sectian head" in the Control Room cn chift. Change his title to Shift Engineer and give him
[ authority over the Operatora on chift.
- 3. Make the Shift Engineer accountable to the Shift
( Supervicor for proper operation of the plant.
- 4. Station the Shift Engineer in the Co . trol Room so that he: (1) can keep track of the status of plant aysteac
( be in position to see plant and equipmentinstrumentation(2)
(3) be in a good po3ition to receive
[ information from other workers in the plant; radiation L chemictry technicians, for inctance.
- 5. From a position in the Control R o o.; , the Shift Engineer
( can evaluate plant ;cnditions based on ca.;plete and timely information, discuss conditions with the operators, and have accesa to Technical Specifications a.id Station Procedures. Frem this information, h: can
( determine the coucae of action necesaary for proper operatice of the plant. From a station in the Control Room, he cln direct Operatora to ts :a p r c.p e t action, wnen nececaary.
- 6. E "; t a O l i C h 'n 0 7 :j a n i z a t i t ;n in each lhift, to inforF LI '
( Station Manager about ;ir;nificant _/en T at the Plant anJ to call ope r a t i on:, and technical p,'rsonnel to tho plant tu al 3 L3t When nec'.5iary. Identify duty aCaignmSOt3 far per.fonnel c a l l -J '} to thG plant. InClPie 1cg ueg1n; reno,n h o iu ca.
Prool ui CJrrectit i ric t i o n Il tne S J, fr i n t e n d 2 n '. Tcchnical JuppOrt had Leen atS!ic]n 1 in th*' Inre+' Mi1e I . 1 e. n d jait [ Contr01 Room aa Ohiit Enginier en March u , o n , :. md _ ep m ,m m tne m x s preg ~iure in the r e a '. o 'l Co')la:lt ly. t em at 0102. He waald n t 'e t e /. p 2 . is t.c e a .'d prom - J alar..ng reactor c;olan: pamp, J ae t;
( m r .m m a mt #. m .m e o n.
l e. : ., . --;c m 0, I.,.,:
-. 0 v .:a
{ _ _ .
lc 5
~.
L r When the Shift Supervisc returned to the Control Room at L 0500, the Superintendent Technical Support as shift Engineer -
accountable to him for proper operation of the plant, would have recommended operating the High Pressure Injection System. The
( Superintendent Technical Support as Shift Engineer, would have recommended operating the High Preasure Injection System based on the plant's design and Stetion Procedures:
( l. Increasing reactor coolant system pressure would return the reactor coolant system to within design limits as stipulated in the Heat Up/ Cool Down Curve.
{
- 2. Increasing reactor coolant system pressure would also return the reactor coolant system to the limits
{ required for operating reactor coolant pumps as stipulated in the Heat Up/ Cool Down Curve.
( 3. Operating the High Pressure Injection System to increase reactor coolaat system precaure is required by plant design if System pressure is below 1640 psig as stipulated in Station Procedure 2202-1.3.
{
The Shift Supervisor was away from the Control Room from 0415 to 0500 in connection with his responsibility to get the Unit back on line. Therefore, he did not experience the conditions and events relating to low pressure of the reactor coolant system. Nor did he have time to review thoroughly pertinent Station Procedures.
The Shift Supervisor, upon returning to the Control Room at 0500, would have recognized the validity of the recommendation
[ to operate the High Precsure Iajection System. He would have recoanized the validity of this recommendation because the recommendation was (1) based on operating the plant ac designed and in conformance with Station Procedurea, (2) made by a man responsible for proper operation of the plant, who was experiencing plant problemc and conditions, and who had time to
( concider pertinent Station Procedures.
Accordingly, at about 3514, the Shift Supervisor would have
( ordered the High Preaaure Injection System operated to increase reactor coolant system pressure and enable reactor coolant pumps to circulate coolant through the reactor core to remove decay heat as designed.
{
The Three Mile Island Unit 2 accident would have been terminated at this time.
(
41 ID4:126SA/ DISC:0068A
{
L_.
t4* ,
If the Superintendent Technical Support had been stationed
[ in the Control Room on March 28, 1979 as Shift Engineer, it is likely that soon after.0400, he would have recognized that there was a serious problem with the Three Mile Island Unit 2 reactor
[ plant.
As Shift Engineer with responsibility for keeping track of
( the status and operability of reactor plant systems, and equipment, he would have been told when he came on ahift about '
midnight, that: (1) the reactor coolant system was leaking,6 and (2) the electromagnetic relief valve was showing open and had been showing open for several months.7 He would have experienced an increase in the reactor coolant system leak rate detected by measurements made on his shift between 0134 and
[ 0234.8 Between 0400 and 0500 he would have experienced the
( following l 0400 Reactor scram
( 0402 High Pressure Injection actuated by low reactor I coolant system pressure !
( 0403 Primary Plant Operator shuts down High Pressure Injection System
( 0407 Reactor Building sump starts automatically 0410 Alarm - neactor Building sump on high level 0412 Reactor Coolant system pressure 1500 psig; pressurize level 400 inches
[. 0414 Reactor Coolant drain tank rupture disc ruptures; pressure in tank decreases from 192 psig to 10 psig in 36 seconda; Reactor Building pressure
( increases by 1 paig 0415 Alarm - Reactor Coolant Pumps Shift Supervisor leaves Control Room 04153 Radiation monitors in Reactor Building ahow 10
( times normal reading 0420 Reactor coolant system pressure 1200 paig;
( pressurizer level decreasing from 400 inches
(
42 ids: 1268A/DI3C:0068A
(
( _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ._
r L
0422 Reactor power increasing Alarms - reactor coolant pump on high vibration
- 0433 Alarm - high temperature in reactor core L
0438 Operator turns off the 2 reactor building sump pumps. Pumps had been pumping water from the Reactor Building cump to the Auxiliary Building cince 0407 0500 Shift Supervisor returns to Control Room having corrected the problem in the condensate system which caused the scram
( Reactor coolant cyatem pressure is 1120 paig; pressurizer level 390 inches CoTaidering the information available to him, it in likely that the Superintendent Technical Support, as Shift Engineer in the Control Room, would have come to the conclusion that the
[ serious ptoblem in the Unit 2 reactor plant was a loss of
, coolant. Being accountable for proper operation of tne plant,
[ he would have ordered the High Preasure Injection System L operated to replace the lost coolant and raine reactor coolant nyatem pressure.
( The Superintendent Technical Support ac Shift Engineer in the Control Rocm would have learned that the reactor coolant sy3 tem was leaking 11en he came en shift. He would have experienced an increaae in the reactor coolant synteT leak shown
( by measurements mado earlier cn his shift. He wCJld h3Ve experienced (1) high lev?1 in the Reactor Building sump at 0410 (2) reactor ccolant nysten presaare 1200 psig and de-
[ creasing at 04l2 (3) reactor coolant drain tans ruoture disc rupturing at 0414 (4) Reactor Building preacute increasing at 0414.
Baand on this intermation, it la likely that the Super-intendent Technical Suppart a s S h i d t- Engineer in tne Control Roam, aculd have c o r, e to the conclusion bafore 0413 tnat the reactor coolant ayateT was leaking.
} He would therefore hav. ; tarted the Hijn Prec ur" I nj :c i.'n L Sya te ' b. fore the fir;t reactor coolant p ump a l a r.a._ -t e r e received at 0413. Reactor coolant ly C t e'i preJJ;ure .?Juld aVV increau d and the deciJica to atop reactor coolant p'..+, a Juld haV- been avert"d. ThJ reactor C0ol3nt GyStem dould ^J7e .
operatcd au de 3 ! ;ned to cool the reactor core and ,eriaus i :c a .; e .
to tn' care would nave been prevented.
43 yD
. :=*-s. o n . .s. - D ,. c m 3 4 .
- s. ?u.s
(
Even if the Superintendent Technical Support present in the
[ Control Room as Shift Engineer had not concluded by 0415 or soon L thereafter, that the Three Mile Island Unit 2 problem was a loss of ccolant accident, it is likely that he would have ordered the r High Pres sure Injection System operated as required by Station L Procedure 2202-1..
g It is likely that he would have given this order because:
t
- l. He was responsible for proper operation of the reactor plant.
r 1
L 2. He had authority over the Primary Plant Operator.
p 3. He was accountable to the Shift Supervtaor.
1
- 4. Proper operatton of the plant means operating the plant as doaigned. By operating in accordance with Station Procedures, the plant is operated as designed.
It is likely that the Superintendent Technical Support, a3
[ Shift Engineer in the Control Room, would have given the order L
to operate the High Pressure Injection System as required by Station Procedure before the Shift Supervisor returned to the Con trol Roo.n a t 0500. 'inen
. the Shif t S up e r '/ i s o r returned to the Control Room, the High Preasure Injection System would have been pumping coolant into the reactor coolant Syatem. Reactor coolant system preacure would have coen :. n c r e a s i n g and the ques-tion et whether or not to stop reactor coolant punpa would have been resolved. The reactor coolant system would then have operated as designed to cool the reactor care and damage to the f reactor core would have been loca cerious.
L w
Station Manager'c Fitat Errcr
"' h e Station ' tanager became Jic.urted acout t Tnrea :li l e Ialand init 2 reactor plant during hia 0315 talop. nu call to the Station. Durinj this call, ho decide 3 to call the Vice Preaident, Generation, Metropolitan EJicon. Before thia call he
[ called t. h e Unit 1 Superintendent and inf ormr! .um of the pe-culiar plant conditiona and cal'.e3 the Maint.'anto :ngineer anj .
l' e q u e a t. c l that t' repott to the Station. The .i t a t i o n :t a n a g e r
( did nothing to Change plant C o n 'i i t l C n 3 d u r i n'J hi, 05l5 t31ephT call to the 3.ation, w .t e '. e r .
He acce;te i jlant cand i t i on; at thiD tihe.
The 3tation M'. nager 1cceptCd plant cuaditi".n.1 at . ht ee Mil-Jaland Unit 2 at 0513 becauce:
- 1. !!e .ad ;cceptcJ n Operiter', , ,Jtt-. ,
d.,n,
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Pre.;Uro In]"c?iCM lyJita relo6 +
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, , 7> -
6
[ _ -- - - - - - - - - - - - - - - - - - - - -- - - - - - - - - --
r e
- 2. He had no guidelines to follow in issuing orders.
Three Mile Island had no policy regard!.ng proper oper-acion of the plant. There were no rules which set a standard for operating and which were followed regularly.
- 3. He was dealing on the telephone with a person who had r no responsibility for proper operation of the plant and
[ this person was not excepted to exercise authority over plant operators.
r Corrective Action - Station Managers' First Error i 1. Institute a follow up corrective action program at L Three Mile Ialand. Objective - to endure that an error like shutting down the High Pressure ~njection Syr, tem on March 29, 1978, is identified, cause determined and I
L corrective action implemented. I
- 2. Establish a Station Policy for operating Three Mile l Island nuclear plants. The Policy should stipalate that each Three Mile Icland nuclear station it to be operated in accordnace with the Facility Operating f Licenae/ Technical Specifications. The Policy should L alco stipulate that operating in accordance vith the Policy requires all peracna to adhere to and comply r with Station Procedurec.
L
- 3. Make the Manager at Three Mile Island who called the Station ".anager, or had him called, responsible for
[
proper operation of the plant. Give him authority over plant Opera: ora and make hir accountable tc the Station Manager for proper operatiano of the plant.
r Ef f ect.vene.sa of cor rective A: tion It is lisely that the Sta tion Manag n would :a, directe3 the S up+4 r i n t end 'n t Tc;c;nical SuppO!O to operat? t'?e High P r e.;a a r ? Injection Sjatem during t L.u i r. 0515 talqR.aae ;all .f:
- 1. Following the March 29, 1978, anJt do cn of '. h e High Preocure Injection Systea, he ud directed a l l. Oper-( ator; and Managerc r e :; p .an a i b l 3 for plant ope r a t i on.: to encui that 3tation P r a e m. n t 2212-1.3 taa tollowe.1 in operating the High Prec;ure I n j e : . i u n a y :; t c u .
- 2. A Poli;y that Threu Mile Ialan 1 Unit 2 w; to'. per-ated in a;cardance wi.a the Operati^.] L i c e n..e an !
( T #.nical 3pecificationc ni that Station P r o: :dar"a me to te sumd, n,d mn w _ n m at nr =
!31and.
45 ID*:1 o i n', ::E6 a E
[
- 3. The caller was responsible for proper operation at the plant and . had authority over the operators.
b Station Manager's Second Error The Station Manager learned during his 0600 conference cell,
[ that reactor coolant pumps were not operating. He knew this was abnormal and that forced circulation of reactor coolant must be reestablished. During this call, he decided to come to the station.
[.
The Station Manager did nothing to change plant conditions during the 0600 conference call, however. He accepted plant conditions at this time because he had no orders to give to the Station.
Corrective Action'for Station Manager's Sacond Error and Ef f ectiveness of Corrective Action:
It is likely that the Station Manager vould have directed the Superintendent Technical Support, during the 0600 conference call, to follow Technical Specifications and Station Procedures
( in ovecoming the problem discussed, and specifically.to operate the High Pressure Injection System as required by Station Procedure 2202-1.3, if:
- 1. He had taken corrective action for the March, 1978 error in shutting down the High Pressure Injection System.
{
- 2. A Policy that Three Mile Island Unit was to be operated in accordance with Technical Specifications and Station Procedures was in effect.
- 3. The caller was responsible for proper operation of the
[ plant and had authority over the operatots.
~
(
Station Manager's Third Errors
( The Station Manager was told by telephone at 0650 that fuel failures had occurred. After arriving in the Unit 2 control roo: at 0705, the Station Manager made no changes in the way the
( plant was being operated. He accepted the mode of operating which had prevailed since 0400.
(
46 IDt:1268A/ DISC:0063A
(
l -- - - - - - - -
The Station Manager accepted the ncde of operating Three Mile Island Unit 2 which had prevailed ince 0400 because:
- 1. He had no orders to give the Operators.
- 2. It was the practice at Three Mile Island to accept the actions of Operators operating the plant.
Corrective Action - Station Manager's Third Error:
- 1. Establish c Station Policy that Three Mile Island is to be operated in accordance with Technical Specifications and Station Procedures.
l 2. Assign a Three Mile Island Manager as Shift Engineer and give him responsibility for proper operation of the plant and authority ove: ~h2 Operators. Station him in the control r oo'n .
Proof of Corrective Action:
If the Station Manager had:
- 1. A Shift Engineer stationed in the Unit 2 control room on March 23, 1979.
- 2. Given the Shift Engineer respansibility for proper operation of Three Mile Island Unit 2.
- 3. Given the Shift Engineer authority over plant Operatorc.
- 4. Implemented a Policy that Three Mile Island Unit 2 was to be operated in accordance with Technical Specifi-c . 'a i o n a and Station ?cacedure;:
The manner in wnich the Three Mile IalanJ Unit 2 reactor plant wan '3ing operated at 0705, when t h e S t <1 t i on ".an c.g c r arrived at the ntaticn, would have been different.
Three Mile Island Oper a t o r:;, unde the supervi:; ion of the Snift Engineer in the contrcl :oom, would . ave operated the Hign Pre;; urn Injection Jyatem at '403 2, required by 3tation Procedure.
And the Taree Mile Island n:c i d n t. tallowing the 0400 rcactor c a r a:n , would not n c.v e teaalted in da:aage to the reactor care.
17 ID*.im u D D i.< : U C'si A f
t
Unit 2 Superintendent's First Error:
The Unit 2 Superintendent arrived in the control roc. at 0545, having been called to the Station because of abnormal plant conditona. After being briefed by the Shift Supervisor, the Unit 2 Superintendent did not change tne manner in which the plant was being operated. He accepted plant conditions despite the fact that there was no circulation of reactor coolant
% rough the core because reactor coolant pumps wrre stopped at 0541.
The Unit 2 Superintendent accepted plant conditions at Three Mile Island Unit 2 at 0545 because:
- 1. He did not take time to cvaluate the Shift Supervicor's decisions to stop reactor coolant pumps.
- 2. He did not feel obligated to take time to evaluate the decisions to stop reactor coolant pumps,
- 3. It was the practice of Managers at Three Mile Ic?.and to accept the actions of Operators.
- 4. Shutting down High Precoure Injection when actuated r follcaing a reactor ceram had been accepted before at L Three Mile Island.
Corrective Action for Unit 2 Superintendent'a First 'cror d
- 1. Make the Unit 2 Superintendent responsible for proper operation of the Three Mile taland r.uclear plants. Change his title to Station Superintendent and agaign a Station Superin~
tendent to Three Mile Ialand daily on a ahitt bacia around the clock.
- 2. Make the Station Saperint n.ont reaponcible for meeting t n e S t a t i o n O b j e ; t i. ' > d u r i n 'j hia shif'. Aaaign hin the r'-
.io u r ae ; , including nanpo...: , ,.omaaa / to neet the Obj ective.
Make hin accoun*able to the Station Manajet for result, en hia chift.
- 3. Corporato Manage. Tent '. : f i n .. Or Jr er operati:n of a Tnroa Mile !aland nu;1.tr plant as:
- 1. Oparating in :cco &nc .c i t h dt :ijn, and theref x s in accorLnce vita .uc.nt;al Speciticition; a n ^!
Station P r ', _ 2 d u r " , ,
- 2. Operatinj caiiably xd e r o.cmic'll',.
- 4. Cor p x a te Man agemn t ..'ine a "Statica Otjectt',e." for e.w plo- "Tne Jtation Ooj"c-ivo of Thr~ Milu : .t l . t n ri 'J n i t 2 M uci 'ar 3taticn ia to guno; a t. ce?;l ;lty and ' y 1i";r t',t :
( ol?ctricity j ner tte ! to ; .l i .rer,.< ii . a 'j;t * . . ic;;r'la:
'2 With the .netill a f r :'" 4 ~ J 1;i 3
/,, ?;. 1 .. nt, l 3 ') ; .ation, M e t P')')31itan Edi.an."
.o ~;*: . ; a- a ,. . m : ,ut i
a
t I
i L
- 5. Station Manager define the "Station Objective" and the c
Policy for proper operation of Three Mile Island Unit 2 for L Station Superintendents. For Example:
"The Station Objective for Three Mile Island Unit 2 is to generate electricity safely, reliably, and economically, and deliver the electricity generated to the transmission syntem in accordance with the schedule promulgated by the Vice President, Gener ation , Met t opolitan Edison .
(
You are rcsponsible for operating Three Mile Island Unit 2 during your chift to achieve the Station's Objective.
To achieve the S tatien Obj ective you are to:
( a. Operate Three Mile Island Unit 2 nuclear plant and sup-porting syatems and equipment to produce electricty as scheduled. Operate means to Operate or maintain the Unit in the Refueling Mode, Cold Shutdown, llo t Shut-
[ down, Ilot Standby, or Low Power Physics Testing, as defined in Techaical Specifications.
- b. Conduct surveillances required by Technical Specifi-cations.
( c. Conduct scheduled maintenance . cork on the nuclear plant and supporting systems and equipnent.
( d. Refuel the nuclear plant when acheduled.
In achieving the Station Objective, cafoly, reliably, and economically:
- a. Safely means in accordan;e 'ti t h *he Facility Operating .
Licende, Technical Specifications, and Codea and Standacds,
- b. Reliably 4 aan: La crerate or yrfccm the other func-tiaa; :o aa to .toet tho acae.lule ior Three Mile 131 and Unit 2 promulgated ty the /icu Preaident, Generation Metrcpalitan Edison,
- c. Econecai c a lly n.can c to perfarr all functions ning sta-u on r enou m in mn eu m unt mnd e a cc u..e ..>n m . .
Station resource. ar . an pa. m , tachinery and "qaip-( ment, f.inC and D u'l j ' t.:d i u n 'i ? . "
- 6. A 0 3 i ~j n a Three 'l i l e r 3 [ ,3 n j ' . 3 3, ;g, ,3 gnt[g gngia y-for Unit 2. StatiQn nin in Unit 2 Control cO'm W'th r e 1,C o n l i ~ .
b1u ty for g:- e . m . m. x m .- o mm e n u 2 and m a u t i'. o r i t y c v a r the Op;r; tori. Mas' nin r w .;tib.o to tho Ji. ' t du; c c V i2i)r .
-t } s ue .s m' . s' \ . s . ).-. .
{ -_ _ - - - - -
- 7. Institute a follow up corrective action program at
( Three Mile Island. The corrective action program should ensure that an error like shutting down the High Pressure Injection System on March 29 1978, is identified, cause determinad and
[ corrective action implemented.
L Proof of Corrective Action:
If the Unit 2 Superintendent had been:
( l. Present at Three Mile Island with the shift starting work around midnight
[ 2. Res pons i b' e for proper operation of Three Mile Island L
Unit 2 to meet an official Corporate schedule for operating
( 3. Accountable to the Station Manager for the outco;ne of his shift:
( He would have taken time to evaluate the Shift Supervisor's decicion to stop reactor coolant pumps.
He would have considered plant conditions as cond i ti on s
{ evolved. He would have experienced these conditions with his shift starting at midnight, f He would have kept in mind that he was accountable to the Station Maaager for the outcomo of operations on his chift.
( He would have considered the requirements of Three Mile Island Unit 2 Technical Specificationa and Stati.on Procedurea.
In light of the condition of Three Mile Island Unit 2, the
( circumat anen sur counding the condition of the plant, and the Station Manager'; guidance regarding proper operation of the r plant, the Unit 2 Superintendent would have directed the Shift
( Supervisor or Shift F.ngineur to operate the Hign Precauce Inj ection ' pt"- w ;en briefed in the control r o o:a .
The Unit 2 Su;erintendeat'a deciaion wu - havo Leen re-inforced by the S t ation Manager 's directive fo all Station Superintendent 3 to be aure that the High Preasure Injectica System 1.- operated in amordance alth Station Procedure 2202-1.3.
{
(
U, n , S upen n .. . e S m o .m :
f Tne Unit 2 Superintend at wu u.;i j ac i re.concibility tor ccnplainee witn pro educo ,
at 0713 t:y the Station Mana;:er.
Af*er thia x:aigr~ tnt, the Un:t 2 Superintendent cantinued tn;
[ m Jde of op 't 30i n ; .h: th' M i 1, y 2JiJad Unit 3 HaiJa had prelailed L
lince 0100 '/ea C.r g n fuei ';.) .r ; ; 11 :2. ted, n
20 ID4: 12 TA D S;;006 G
The Unit 2 Superintendent continued the mode of operating Three Mile Island Unit 2 at 0715 because:
- 1. This was the mode accepted by the Station Manager and he did not feel obligated to make a change.
- 2. It was the practice of three Mile Island Managers to accept the action of the Operatoes.
L Co rective Action for Unit 2 Super'Stendent's Second Error and Proof of Corrective Action:
If ...e Unit 2 Superintendeat. nad been present at Three Mile Island, starting at midnight , 23 Station Superintendent, with
( responsibility for proper operation of Three Mile Island Unit 2 to meet a schedule of operatinns,
( And if he had been accoantable to the Station Manager for the performance of the Station on his shift, And if he had been directed by the Station Manager to follow
{ a Station Policy that Three Mile Island Unit 2 was to be oper-ated in accordance with Technical Specifications and Station Procedures in meeting scheduled operations, And if a Shift Engt.eer had been stationed in the control rocm to asnist and super"ice Coeratora in operating the plant, And if the Station Manager, when correcting the March, 1973 error in shutting dowa the High Precaure Injection System, had directed Station Superintendents to operate the High Preccure
{ I.ijection System aa required by Station Procedure 2202-1.3 --
A ditferent mode of operating would have prevailed at Three
[ Mile Inland Unit 2 on March 23, 1979:
Operators would nave cc:n following Statica Procedure., in operating Three Mil < I3 land Unit 2.
A Snift Engine;r in the Unit 2 control room would have been supervi.;ing op?rationa.
(
The Prinary Jiant 0:erator under tne cognizanct of the Shitt Engint ,r, 'ould
. anve opetate; th" Higr. Prec';ur.' Injectica Syat.'
( follcwing the 0100 reactor ;c r a.m . Jho reactor coolant s y ;t mn WOuld hav> i J:i j i one:i a: d;J1jnOu t ') COJ1 the r e .t C l O r Cor' 105 thO redetar Cur 0 W J.; 'J 1 < } !.O t have Leen d.4.Lugel Juring tlc IcCi-dent.
51 ID*: 12 6 3 A/DI3s': 000JA
{
s L
Operators and Managers would have been operating the plant
[ properly at 0715 on March 28, 1979, and there would have been no L need for the Unit 2 Superintendent to change the mode of operating Three Mile Island U. nit 2.
Unit 1 Operations Supervisor'c Error P At 0715, the Unit 1 Operations Supervisor continued the mode of operating Three Mile Island Unit 2 which had prevailed since f 0400, even though fuel failures had occurred. When the Station Manager assigned him resonsibility for operations and responsi-r bility to direct the Shift Supervisor, the Unit 1 Operations
( Supervisor coatinued the same mode of operating because:
- 1. He was already involved in plant operations having been
( asked to assist by the Shift Supervisor at 0600.
- 2. He was under no obligation to review the decisions already made concerning plant operations.
[
Corrective Action for Unit 1 Operations Supervisor's Error and
( Proof of Corrective Action:
If a shift Engineer had been stationed in the Three Mile
{ Island Unit 2r antrol Room on !! arch 28, 1979:
- 1. With responsibility for operating the plant in I accordance with design.
1
- 2. With authority over the Operators and
( 3. Accountable for his actions.
There would have been no need to assign the Operations
( Supervisor from Unit 1 responsibill' y for operating Unit 2 at 0715.
There would have been no need to sesign the Unit 1 Opera-
[ tions Supervisor responsibilicy for operating Unit 2 at 0715 because Unit 2 would have been operating under the Shif t r Engineer in accordance with design. Therefore, the loss of L coolant accident would have been terminated by the High Pressure {
Injection System at 0402.
(
1
(
52 ID4:1268A/ DISC:006SA f
l .'
L
- a. \
> REFERENC 4 i
Report of'the President's Commissicn on THE ACCIDENT AT THREE MILE ISLAND (To identify participants, and to verify facts and
( continuity)
INVESTIGATION INTO THE MARCH 28, 1979 THREE MILE ISLAND
{ ACCIDENT BY OFFICE OF INSPECTION AND ENFORCEMENT (USNRC Deport NUREG - 0600)
[ Preliminary - Description of Events at the Three Mile Island 2 5
Facility Accident; NRC Document dated April 10, 1979
\
2 FOOTNOTES
- 1. NRC Document dated April 10, 1979, titled "Preliminary -
Description of Events at ' he Three Mile Island 2 Facility
[ Accident"; control Room E crip Charts attached to this document.
( 2. "INVESTIGATION INTO THE MARCH 28, 1979 THREE MILE ISLAND ACCIDENT BY OFFICE OF INSPECTION AND ENFORCEMENT" (USNRC Report NUREG - 0600) f p. I-2-25 Technical Specification 3.3.2, Engineered Gafety Featute Actuelloa .7jstem
- p. I-2-20 Technical Specification 3.5.2, Safe.y Fea-turns Actuation System; Procedure 2105-1.3, Safety Fonteres Actuation System; Procedure 2202-1.3 Losc f of Reactor Coolant /Reacter Coolant System Pressure
- 3. ibid p. I-4-29 Operating Procedure 3102-1.1, Unit f Heatup; Frocedure 2104-1.1, Core Flood; Technical Specification 6.8.1.a (Requirement to follow Station Procedures)
- 4. Hid p. I-2-32 Technical Specifications 3.4.9.1; Procedure 2103-1.4 Reac. r Coolant Pump Operation; Procedure 2102-3.3 Deca Heat Removal Via OTSG
- p. I-4-25 Procedure 2103-1.4
( 5. ibid pp. I-1-44, I 1, I-2-50, I-4-ll
- 6. ibid pp. I-1-2, I- I-1-5
- 7. ibia pp I-1-2, I - t .s 4
- 8. ibid pp I-1-2, I-1-4 53 IDf: 126SA/ DISC:0068A
t UNIT (3 StaTL5 O*
', ', , , .[ps set .1\, NUCLE AR REGULATORY COMMissi:N g' t. ",
- CE OloN ill l; g
-j ses moossvg67 sean GL EN ELLYN. ILLINOll 60937
\ * ..* / ,
MAR 4i Igag Docket No. 50-237 Docket No. 50-249 Docket No. 50-254 Docket No. 50-265 Mr. Charles Young 262 Sheffield Lane Glen Ellyn. IL 60137
SUBJECT:
ALLEGED HAZARDOUS PRACTICES AT COMMONWEALTH EDISON NUCLEAR POWER PLANTS (AITS NO. F03004988)
We received your letters dated January 29 and February 24. l'988, that provided your Plants. concerns of alleged hazardous practices at Commonwealth Edison Nuclear In general tertns your concerns were: (1) employees work near a nuclear reactor producing power at Dresden and Quad Cities Stations endangering their eyes and violating fuel meltdown containment requirements; and (2) the company risks a nuclear by auth a
during an emergency, orizing operators to turn off a nuclear plant safety system
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49 your concern about the hazards to employees working near reactors while producing power while it is true that radiation workers perform work in the drywells at Dresden and Quad Cities nuclear power stations at power, we have concluded that such work is only infrequently performed and then only within established restrictions on power level and radiological monitoring. The nomal operating condition is for the drywell to be inerted, and barred to personnel access.
The restrictions were established in acknowledgement of the increased radiological environment as well as the increased potential for nonradiological safety hazards.
Several years ago Dresden and Quad Cities Stations hsd Battelle Pacific Northwest Laboratories detertnine neutron energy and flux in their drywells at power to ensure that their neutron survey instruments and dosimeters properly at entering determine power. neutron dose equivalent rate and dose for oersons The neutrou dose equivalent rates measurea inside Dresden Unit 3 drywell while the reactor was operating at 201 power varied from 0.3 to 1.0 mrem /hr as measured t,y Battelle Pacific Northwest Laboratories on May 4. 1985 using e tissue equivalent proportional counter and He-3 spectrometer in conjunction with the licensee's survey instruments and personnel neutron dosimetry.
drywell for the measurements. Five different locations were chosen in the ative of the radiological conditions that would affect a worker in theThese loca drywell with the reactor at power.
than the garra dose rates at all locations.Tht neutron dose rates were far lower In accordance with plant procedures, drywell entries during plant power operation will only occur with reactor power at or below 40%, and will be perfntmed by management personnel.
Our procedure reviews and inspections have found that (1) this r type of entry is usually to detemine the source of leakage from the prirary -
system or for an equipment inspection; (2} that under no conditions will a drywell entry be rade when the drywell is irerted; (3) that pemission to ,
make a drywell entry has to be first approsed by either the Production s.-
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Mr. Charles Young 2 MAR 3a1M Superintendent or the Assistant Superintendent of Operations; and (4) that each individual entering the drywell while the reactor is critical wears neutron dosimetry in addition to beta-gamma dosimetry. For persons entering the drywell, both the neutron and gama doses are detemined and ;
are additive. The licensee must ensure that 10 CFR Part 20 limits are not exceep '; these limits are set well below any known hartnful effects to a pers :. s whole body including the eyes. Our inspections of -
Comonwealth Edison Company's programs and procedures regarong employee exposure to radiation have found them to be in accordance with our regulations.
While we share your concern about increased radiological safety hazards incident to working in drywells at power, our inspections have shown that Comonwealth Edison Company has imposed sufficient controls to minimize these hazards while accomodating operational demands. We will, however, continue to monitor the licensee s perfomance in this are3 through our inspection program to ensure their controls remain effective.
You also expressed a concern that drywell entries with the reactor operating violated containment requirements. Technical Specification-3.7.A.2 states, in part, that primary containment integrity shall be
- maintained at all times when the reactor is critical cr when the reactor water temperature is above 212'F and fuel is in the reactor vessel.
. Because of the double door airlock system on the primary containment,
- entry at power can be made without compromising containment integrity; I
therefort, Technical Specification 3.7 A.2 is met and there is no violation of the operating license or the Atomic Energy Act of 1954.
I This conclusion does not differ from the conclusion previously stated on page 70 of our Inspection Report 50-273/81-39; 50-249/81-32, which is attached. ;
- 2. With regard to your concern with the authorization of operators to turn off :
' a safety system during an emergency, this was reviewed in our inspection
! report 50 237/81-39; 50-249/81-32. This report acknowledged that situations may Jrise when it may bJ necessary to operate outside the station procedures or Technical Specifications (see pages 25 and 26). ,
Since that inspection report, Federal Regulation 10 CFR 50.54(x) h6s been issued which authorizes a licensee to take reasonable action that departs from a license condition or a Technical Specification, such as turning off a safety system in an emergency. This action is pemitted when imediately ,
i needed to protect the public health and safety and no action consistent I with license conditions and Technical 3pecifications that can provide adequate or equivalent protection is imediately apparent. Federal j Regulation 10 CFR 50.54(y) requires that any such action be approved, as l
a minimum, by a licensed senior operator prior to taking the action. In addition, the NRC will review any circumstances where a licensee invokes 10 CFR 50.54((x) to assure its appropriate use. This regulatior has not been used at Dresden or Quad Cities to date. The licensee's procedures '
and, in particular, the policy you referenced, "Vice President's Instruction '
No. 1-0-17," have been reviewed and found to comply with the requirements of 10 CFR 50.54(x) and (y) therefore, there is no violation of the Atomic Energy Act of 1954.
Mr. Charles Young 3 gg 31 jg You also stated a ccncern that the licensee's operating policy would permit emergency core cooling to be turned off with stable reactor parameters of low pressure, high temperature, and low level resulting in core damage. This hypothetical combination could not be interpreted as "stable and under control" as called for by the policy. If conditions existed sufficient to cause core damage, then reactor pressure and level would have to be changing or other evidence of inadequate core cooling present such as reactor vessel level so low as to be out of the indicating range. The policy also requires that:
"In all such instances such action should be taken only after careful con-sideration, and most be reviewed and approved by the licensed Senior Reactor Operator insnediately available." This would preclude any individual operator frorn independently taking such an action. If operators are not permitted to exercise judgement in this area, the multiple emergency cooling systems with redundant capacities to add water to the reactor could cause other undesirable effects such as overfilling the reactor or injecting water from less desirable Idue to cleanliness) backup sources. Obviously, safety system automatic actuations and Technical Specifications cannot prescribe actions for every
' combination of conditions, but are designed to meet the most extreme circum-stances. The granting of authority to licensed reactor plant operators to '
respond in an emergency to protect the public health and safety was deemed necessary and was made a part of Federal Regulation (10 CFR 50.54(x) and (y)).
The Commonwealth Edison Company policy imolementing this policy has been reviewed and found to be in accordance with the regulations.
I i Based on the discussion above, we do not agree that your concerns represent
- violations of federal regulations. Since no violations of our requirements have been identified, no further action is intended at this time. I hope this adequately addresses your concerns.
Sincerely. ,
i vg b.
EdwaF6 G. Greenma'h, Director
\ ' lh Division of Reactor Projects
Attachment:
Inspection Report:
50-237/81-39(OPRP) 50-249/81-32(DPRP) 50-254/81-23(DPRP) 50-265/81-23(OPRP) l 50-295/81-31 DPR?
50-304/81-29 DPRP cc w/ attachment:
Thecas Rehm EDO Assistant for Operations l
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<g e...*j attw attvw. Luwois eom g01.12 1982 Docket Nos. 50 237, 50 249; 50-254, 50 265; 50-295, 50 304 Coeconwealth Edison Company
- ATTN: Mr. Cordell Reed Vice President Post Office Box 767 Chicago, IL 60690 Gentlemen:
This refers to the specal inspection conducted by D. V. Hayes and other NRC Region !!! staff members relative to activities at the Dresden, Quad Cities and Zion Nuclear Power Plants authorized by NRC Operating Licenses No. DPR-19, No. DPR 25, No. DPR 29, No. DPR 30, No. DPR 39. and DPR 48 No his staff on May 3,1982.and to the discussion of our fincings with Mr. J. J. O'Conn durinE the period August 13,The purpose of the special inspection, conducted 1981 concerns expressed by an individual relative to Commonwealth Edisonthr
- Corpany's operation of these nuclear plants and compliance to 10 CFR Part 21 reporting requireeents.
The enclosed copy of our inspection report identifies areas examined during the inspection.
examination terviews of procedures with personnel. and representative records, observa Although no items of noncoepliance with h7C requirements were identified during this inspection, we are concerned with several apparent weaknesses
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Coar.xnvealth Edis n Company 2 in your program.
aseeting and are summarized in Section D of the attached report.T Please have taken or plan to take relative to these matters. advise us withi Specifically (1) plans to clarify policies and procedures and improve training to assure no conflict exists in tha minds of plant operators between continued plant availability and conservative operating practices, (2) improvements in onsite and offsite reviews and evaluations of plant events including corrective measurestimeliness, adequacy of content and recoenndations and to prevent recurrence, (3) steps to assure root causes of scrams and equipment es1 functions are identified and corrected prior to resumption of plant operation, and (4) plans to improve uniform implementa-tion of company wide policies and procedures between stations and to assure that benefits from station experiences are being fully shared .
In accordance with 10 CFR 2.790 of the Commission's regulations, a copy of this letter, the enclosures, and your response to this letter will be placed in the SRC's Public Document Room.
that you (or your contractors) believe to be exemptIf this report contains any informa free disclosure under phone within ten (10) days from the date of this letter of you to file a request for withholding; and (b) submit within twenty-five (25) days from the date withhold such information. of this letter a written application to this office to delayed such that If your receipt of this letter has been
- please lished. notify this office promptly so that a new due date may be esta Consistent with Section 2.790(b)(1), any such application must be accor nnied by an affidavit executed by the owner of the information which identifies the document or part sought to be withheld, and which containc claim that a full statement of the reasons which are the bases for the the information should be withheld from public disclosure.
This section further requires the statement to address with specificity the considerations listed in 10 CFR 2.790(b)(4).
to part beofwithheld sha11 be incorporated as far as possible into a separateThe informatio the affidavit.
If we do not hear from you in this regard within the specified periods noted above, a copy of this letter, the enclosures and your response to this letter will be placed in the Public Document Room.
., :., *l-Coseonwealth Edison Company 3 We will gladly discuss any questions you have concerning this inspection.
Sincerely.
Original signed by Ja-cs G. Keppler 3' James G. Keppler Regional Administrator cc: Louis 0. De1 George, Director of Nuclear Licensing D. J. Scott, Station Superintendent N. Kalivianskis, Plant Superintendent X. L. Graesser, Station Superintendent DMB/ Document Control Desk (RIDS)
Resident Inspector, RIII Karen Borgstadt, Office of Assistant Attorney General Mayor John B. Spencer
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