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{{#Wiki_filter:KuUNITED STATESNUCLEAR REGULATORY COMMISSIONOFFICE OF NUCLEAR REACTOR REGULATIONWASHINGTON, D.C. 20555September 14, 1993NRC INFORMATION NOTICE 93-72: OBSERVATIONS FROM RECENT SHUTDOWN RISK ANDOUTAGE MANAGEMENT PILOT TEAM INSPECTIONS
{{#Wiki_filter:Ku UNITED STATES NUCLEAR REGULATORY
 
COMMISSION
 
===OFFICE OF NUCLEAR REACTOR REGULATION===
WASHINGTON, D.C. 20555 September
 
14, 1993 NRC INFORMATION
 
NOTICE 93-72: OBSERVATIONS
 
FROM RECENT SHUTDOWN RISK AND OUTAGE MANAGEMENT
 
===PILOT TEAM INSPECTIONS===


==Addressees==
==Addressees==
All holders of operating licenses or construction permits for nuclear powerreactors.
All holders of operating
 
licenses or construction
 
permits for nuclear power reactors.


==Purpose==
==Purpose==
The U.S. Nuclear Regulatory Commission (NRC) is issuing this informationnotice to inform addressees of observations from recent shutdown risk andoutage management pilot team inspections. It is expected that recipients willreview the information for applicability to their facilities and consideractions, as appropriate, to avoid similar problems. However, suggestionscontained in this information notice are not NRC requirements; therefore, nospecific action or written response is required.BackgroundEvents that occurred during the past several years have caused the NRC staffto be increasingly concerned about plant safety during shutdown operations.The Diablo Canyon event of April 10, 1987, in which boiling of the reactorcoolant resulted from a loss of decay heat removal, highlighted the fact thatoperation of a pressurized-water reactor with a reduced reactor coolant system(RCS) inventory is a particularly sensitive condition. Based on its review ofthat event, the staff issued Generic Letter 88-17, "Loss of Decay HeatRemoval," October 17, 1988, which requested that licensees address certaingeneric deficiencies to improve safety during operations with a reduced RCSinventory. More recently, Incident Investigation Team report, NUREG-1410,"Loss of Vital ac Power and the Residual Heat Removal System During Mid-LoopOperations at Plant Vogtle Unit 1 on March 20, 1990," emphasized the need forrisk management of shutdown operations. Discussions with foreign regulatoryorganizations support NRC staff findings that the core-damage-frequency forshutdown operations may be a substantial fraction of the total core-damagefrequency.
The U.S. Nuclear Regulatory
 
Commission (NRC) is issuing this information
 
notice to inform addressees
 
of observations
 
from recent shutdown risk and outage management
 
pilot team inspections.
 
It is expected that recipients
 
will review the information
 
for applicability
 
to their facilities
 
and consider actions, as appropriate, to avoid similar problems.
 
===However, suggestions===
contained
 
in this information
 
notice are not NRC requirements;  
therefore, no specific action or written response is required.Background
 
Events that occurred during the past several years have caused the NRC staff to be increasingly
 
concerned
 
about plant safety during shutdown operations.
 
The Diablo Canyon event of April 10, 1987, in which boiling of the reactor coolant resulted from a loss of decay heat removal, highlighted
 
the fact that operation
 
of a pressurized-water
 
reactor with a reduced reactor coolant system (RCS) inventory
 
is a particularly
 
sensitive
 
condition.
 
Based on its review of that event, the staff issued Generic Letter 88-17, "Loss of Decay Heat Removal," October 17, 1988, which requested
 
that licensees
 
address certain generic deficiencies
 
to improve safety during operations
 
with a reduced RCS inventory.
 
More recently, Incident Investigation
 
Team report, NUREG-1410,"Loss of Vital ac Power and the Residual Heat Removal System During Mid-Loop Operations
 
at Plant Vogtle Unit 1 on March 20, 1990," emphasized
 
the need for risk management
 
of shutdown operations.
 
Discussions
 
with foreign regulatory
 
organizations
 
support NRC staff findings that the core-damage-frequency
 
for shutdown operations
 
may be a substantial
 
fraction of the total core-damage
 
frequency.
 
Description
 
of Circumstances
 
Between December 1991 and April 1993, the NRC staff conducted
 
five pilot team inspections
 
to assess the effectiveness
 
of industry initiatives
 
for improving shutdown safety. The inspections
 
were performed
 
at Oconee Nuclear Station, Unit 2 [NRC Inspection
 
Report (IR) 50-270/91-202], Indian Point Nuclear 9309090243
-U 1?-.crn-9
.3 IN 93-72 September
 
14, 1993 Generating
 
Station, Unit 3 (IR 50-286/92-901), Diablo Canyon Nuclear Station, Unit 1 (IR 50-275/92-201), Prairie Island Nuclear Generating
 
Plant, Units 1 and 2 (IR 50-282/92-201;
50-306/92-201), and Cooper Nuclear Station (IR 50-298/93-201).
 
Approximately
 
one week of each inspection
 
focused on licensee pre-outage
 
planning and control processes
 
and 8 to 10 days focused on licensee implementation
 
of the outage.In the pre-outage
 
portion of the inspection, the inspectors
 
evaluated
 
the following:
(1) management
 
involvement
 
in and oversight
 
of the outage planning process, (2) planning and scheduling
 
of outage activities, especially
 
the relationships
 
between significant
 
work activities
 
and the availability
 
of electrical
 
power supplies, decay heat removal systems, reactor coolant system RCS inventory
 
and containment
 
integrity, (3) the process for developing
 
individual
 
work packages to ensure coordination
 
with other activities, and (4)operator response procedures, contingency
 
plans and training for mitigation
 
of loss of decay heat removal capability, loss of RCS inventory
 
and loss of electrical
 
power sources during shutdown conditions.
 
The inspectors
 
walked through procedures
 
related to shutdown safety to determine
 
if the specified
 
activities
 
could be accomplished
 
in the allotted time frames and to verify that the procedures
 
could be implemented
 
considering
 
probable equipment
 
availability.
 
The inspectors
 
reviewed training records on outage procedures
 
to determine
 
if the training was adequate and that, when appropriate, additional
 
training was provided as the procedures
 
were revised.The inspectors
 
also evaluated
 
the probable effects of environmental
 
conditions
 
such as temperature, steam and flooding on the performance
 
of activities
 
that would be required to mitigate adverse shutdown events.In the implementation
 
portion of the inspection, the inspectors
 
evaluated:
(1) the control of changes to the outage schedule, control of work activities, and control of system alignments, (2) the working relationships
 
and communication
 
channels between operations, maintenance
 
and other plant support personnel, (3) the conduct of operations
 
personnel
 
both inside and outside of the control room regarding
 
awareness
 
of plant status, control of plant evolutions, response to alarms and other abnormal indications, (4) the completeness
 
and effectiveness
 
of shift turnovers, (5) whether maintenance
 
and modification
 
work was performed
 
in accordance
 
with current written and approved procedures
 
and appropriate
 
post-maintenance
 
testing was required and performed, and (6) the adequacy of management
 
involvement
 
and oversight
 
of the conduct of the outage as it progressed.
 
Other areas observed were, plant housekeeping, normal and emergency
 
plant lighting, configuration
 
control, radiological
 
controls, equipment
 
labeling and status tagging, vital area access control, use of overtime and licensee control of contractor
 
work including
 
contractor
 
training and qualifications.
 
Discussion
 
In general, the inspectors
 
found that licensees
 
had instituted
 
programmatic
 
changes developed
 
from guidance contained
 
in a Nuclear Management
 
and Resources
 
Council document, NUMARC 91-06, "Guidelines
 
for Industry Actions to
 
TV IN 93-72 September
 
14, 1993 Assess Shutdown Management." The team inspectors
 
found individual
 
examples of licensee failure to follow procedures
 
but more importantly
 
the inspectors
 
identified
 
two areas of more general concern: (1) risk assessment
 
for pre-outage
 
planning, emergent work and schedule changes, and (2)implementation
 
of defense-in-depth
 
methodologies
 
for equipment
 
availability.
 
A general discussion
 
of these areas is provided below. Specific details of the findings are contained
 
in the inspection
 
reports referenced
 
above.Risk Assessment
 
for Pre-Outage
 
Planning, Emergent Work and Schedule Changes The inspectors
 
found that licensees
 
used various programmatic
 
controls to assess shutdown risk factors during initial outage planning, emergent work and schedule changes. Assessment
 
methodologies
 
used for initial outage planning ranged from following
 
minimum guidelines
 
for equipment
 
availability
 
to performing
 
a probabilistic
 
risk assessment
 
of scheduled
 
outage activities.
 
The inspection
 
team found that the risk assessment
 
aided the licensee in identifying
 
activities
 
that would be subject to high risk during the sched led outage. However, as the outage progressed, the risk assessment
 
became less valid because it was not updated as changes to the outage schedule occurreda In the areas of emergent work and schedule changes, the inspectors
 
found that three of the plants had a proceduralized
 
process to assess the effect of \emergent work or schedule changes on plant risk. The other two plants relied on a functional
 
review by planners, schedulers, and operators
 
to adjust the schedule appropriately
 
to reduce risk.The inspectors
 
found that all of the plants maintained
 
status boards or checklists
 
in the control room to assist the operators
 
in tracking the configuration
 
status of plant systems and to help identify potential risk-significant
 
activities.
 
Implementation
 
of Defense-in-Depth
 
for Equipment
 
===Availability===
The inspection
 
teams found that licensee implementation
 
of defense-in-depth
 
for equipment
 
availability
 
was inconsistent.
 
Although industry guidelines
 
for declaring
 
equipment "available" exist, the inspectors
 
found that the criteria for declaring
 
equipment
 
needed to ensure an appropriate
 
margin of safety"available" varied from licensee to licensee.
 
For example, declaring
 
that equipment
 
was "available" did not always include ensuring that support systems (e.g., cooling water and heating, ventilation
 
and air conditioning)
were also available.
 
At times, after maintenance
 
had been performed, equipment
 
was listed as "available" without the benefit of a post-maintenance
 
functional
 
test. The inspectors
 
also found that some equipment
 
was considered
 
to be"available" even though actions, such as removal of clearances
 
or realignment
 
of valves, would be required before the equipment
 
could perform its function.In addition to the above concerns, at most of the plants the team inspectors
 
found examples of failures to comply with technical
 
specification
 
restrictions
 
on overtime work in that management
 
approval to exceed overtime limits was inadequately
 
documented.
 
K-, This information
 
notice requires no specific action or written response.
 
If you have any questions
 
about the information
 
in this notice, please contact the technical
 
contact listed below or the appropriate
 
Office of Nuclear Reactor Regulation (NRR) project manager.Brian K. Grimes, Director Division of Operating
 
===Reactor Support Office of Nuclear Reactor Regulation===
Technical
 
contact: J.D. Wilcox, NRR (301) 504-1262 Attachment:
List of Recently Issued NRC Information
 
Notices RSIB:DRIL:NRR
 
JDWilcox 07/02/93 RPB:ADM NBeeson 08/10/93 RSIB:DRIL:NRR
 
SSanders 07/02/93 OGCB:DORS:NRR
 
===JLBirmingham===
08 /1/ 93 J9 AC/RSIB:DRIL:NRR
 
DNorkin 07/02/93 C70MO:DORS:NRR
 
iGHMarcus PT ;S/Al/93 D/DRIL:NRR
 
CERossi 07/10/93 D/DORS:NRR
 
BKGrimes 09/ /93 RSIB:DRIL:NRR
 
PSKoltay 07/06/93
-IN 93-xx September
 
xx, 1993 This information
 
notice requires no specific action or written response.
 
If you have any questions
 
about the information
 
in this notice, please contact the technical
 
contact listed below or the appropriate
 
Office of Nuclear Reactor Regulation (NRR) project manager.Brian K. Grimes, Director Division of Operating
 
===Reactor Support Office of Nuclear Reactor Regulation===
Technical
 
contact: J.D. Wilcox, NRR (301) 504-1262 Attachment:
List of Recently Issued NRC Information
 
Notices*SEE PREVIOUS CONCURRENCE
 
*RSIB:DRIL:NRR
 
*RSIB:DRIL:NRR
 
JDWilcox SSanders 07/02/93 07/02/93*AC/RSIB:DRIL:NRR
 
DNorkin 07/02/93> C/OGCB:DORS:NRR
 
GHMarcus/Wen
 
08/27/93*D/DRIL:NRR
 
CERossi 07/10/93 D/DORS:NRR
 
BKGrimes 09/ /93*RPB:ADM NBeeson 08/10/93*OGCB:DORS:NRR
 
===JLBirmingham===
08/27/93*RSIB:DRIL:NRR
 
PSKoltay 07/06/93 DOCUMENT NAME: OUTAGEIN.JLB
 
'-vJ IN 93-72 September
 
14, 1993 Based on the five pilot inspections, the NRC inspection
 
teams concluded
 
that NRC actions and industry initiatives
 
have increased
 
licensee awareness
 
of the risk associated
 
with shutdown and low power conditions.
 
The inspection
 
teams found that licensees
 
were aware of the necessity
 
for ensuring that required systems be available
 
and of the need to maintain the capability
 
of backup equipment
 
during an outage. However, the inspection
 
teams found that licensee interpretations
 
of industry initiatives
 
for addressing
 
shutdown risk varied greatly. This was demonstrated
 
by the various licensee interpretations
 
of industry guidelines
 
for declaring
 
equipment "available." This information
 
notice requires no specific action or written response.
 
If you have any questions
 
about the information
 
in this notice, please contact the technical
 
contact listed below or the appropriate
 
Office of Nuclear Reactor Regulation (NRR) project manager.Original signed by Brian K. Grimes Brian K. Grimes, Director Division of Operating
 
===Reactor Support Office of Nuclear Reactor Regulation===
Technical
 
contact: J.D. Wilcox, NRR (301) 504-1262 Attachment:
List of Recently Issued NRC Information
 
Notices*SEE PREVIOUS CONCURRENCE
 
*RSIB:DRIL:NRR
 
*RSIB:DRIL:NRR
 
JDWilcox SSanders 07/02/93 07/02/93*AC/RSIB:DRIL:NRR
 
DNorkin 07/02/93*C/OGCB:DORS:NRR
 
GHMarcus/Wen
 
08/27/93*D/DRIL:NRR
 
CERossi 07/1 dJ3 (qy*RPB:ADM NBeeson 08/10/93*OGCB:DORS:NRR
 
===JLBirmingham===
08/27/93*RSIB:DRIL:NRR
 
PSKoltay 07/06/93 DOCUMENT NAME: 93-72.IN
 
IN 93-72 September
 
14, 1993 Based on the five pilot inspections, the NRC inspection
 
teams concluded
 
that NRC actions and industry initiatives
 
have increased
 
licensee awareness
 
of the risk associated
 
with shutdown and low power conditions.
 
The inspection
 
teams found that licensees
 
were aware of the necessity
 
for ensuring that required systems be available
 
and of the need to maintain the capability
 
of backup equipment
 
during an outage. However, the inspection
 
teams found that licensee interpretations
 
of industry initiatives
 
for addressing
 
shutdown risk varied greatly. This was demonstrated
 
by the various licensee interpretations
 
of industry guidelines
 
for declaring
 
equipment "available." This information
 
notice requires no specific action or written response.
 
If you have any questions
 
about the information
 
in this notice, please contact the technical
 
contact listed below or the appropriate
 
Office of Nuclear Reactor Regulation (NRR) project manager.C-Brian K. Grimes, Director Division of Operating
 
===Reactor Support Office of Nuclear Reactor Regulation===
Technical
 
contact: J.D. Wilcox, NRR (301) 504-1262 Attachment:
List of Recently Issued NRC Information
 
Notices
 
===KJ Attachment===
IN 93-72 September
 
14, 1993 LIST OF RECENTLY ISSUED NRC INFORMATION
 
NOTICES Information
 
Date of Notice No. Subject Issuance Issued to 93-71 93-70 93-69 93-68 92-16, Supp. 2 93-67 93-66 93-65 Fire at Chernobyl
 
Unit 2 Degradation
 
of Boraflex Neutron Absorber Coupons Radiography
 
Events at Operating
 
Power Reactors Failure of Pump Shaft Coupling Caused by Temper Embrittlement
 
during Manufacture
 
Loss of Flow from the Residual Heat Removal Pump during Refueling Cavity Draindown Bursting of High Pressure Coolant Injection
 
Steam Line Rupture Discs Injures Plant Personnel Switchover
 
to Hot-Leg Injection
 
Following A Loss-of-Coolant


==Description of Circumstances==
Accident in Pres-surized Water Reactors Reactor Trips Caused by Breaker Testing with Fault Protection
Between December 1991 and April 1993, the NRC staff conducted five pilot teaminspections to assess the effectiveness of industry initiatives for improvingshutdown safety. The inspections were performed at Oconee Nuclear Station,Unit 2 [NRC Inspection Report (IR) 50-270/91-202], Indian Point Nuclear9309090243-U 1?-.crn-9 .3 IN 93-72September 14, 1993 Generating Station, Unit 3 (IR 50-286/92-901), Diablo Canyon Nuclear Station,Unit 1 (IR 50-275/92-201), Prairie Island Nuclear Generating Plant, Units 1and 2 (IR 50-282/92-201; 50-306/92-201), and Cooper Nuclear Station(IR 50-298/93-201). Approximately one week of each inspection focused onlicensee pre-outage planning and control processes and 8 to 10 days focused onlicensee implementation of the outage.In the pre-outage portion of the inspection, the inspectors evaluated thefollowing: (1) management involvement in and oversight of the outage planningprocess, (2) planning and scheduling of outage activities, especially therelationships between significant work activities and the availability ofelectrical power supplies, decay heat removal systems, reactor coolant systemRCS inventory and containment integrity, (3) the process for developingindividual work packages to ensure coordination with other activities, and (4)operator response procedures, contingency plans and training for mitigation ofloss of decay heat removal capability, loss of RCS inventory and loss ofelectrical power sources during shutdown conditions.The inspectors walked through procedures related to shutdown safety todetermine if the specified activities could be accomplished in the allottedtime frames and to verify that the procedures could be implemented consideringprobable equipment availability. The inspectors reviewed training records onoutage procedures to determine if the training was adequate and that, whenappropriate, additional training was provided as the procedures were revised.The inspectors also evaluated the probable effects of environmental conditionssuch as temperature, steam and flooding on the performance of activities thatwould be required to mitigate adverse shutdown events.In the implementation portion of the inspection, the inspectors evaluated:(1) the control of changes to the outage schedule, control of work activities,and control of system alignments, (2) the working relationships andcommunication channels between operations, maintenance and other plant supportpersonnel, (3) the conduct of operations personnel both inside and outside ofthe control room regarding awareness of plant status, control of plantevolutions, response to alarms and other abnormal indications, (4) thecompleteness and effectiveness of shift turnovers, (5) whether maintenance andmodification work was performed in accordance with current written andapproved procedures and appropriate post-maintenance testing was required andperformed, and (6) the adequacy of management involvement and oversight of theconduct of the outage as it progressed.Other areas observed were, plant housekeeping, normal and emergency plantlighting, configuration control, radiological controls, equipment labeling andstatus tagging, vital area access control, use of overtime and licenseecontrol of contractor work including contractor training and qualifications.DiscussionIn general, the inspectors found that licensees had instituted programmaticchanges developed from guidance contained in a Nuclear Management andResources Council document, NUMARC 91-06, "Guidelines for Industry Actions to


TVIN 93-72September 14, 1993 Assess Shutdown Management." The team inspectors found individual examples oflicensee failure to follow procedures but more importantly the inspectorsidentified two areas of more general concern: (1) risk assessment forpre-outage planning, emergent work and schedule changes, and (2)implementation of defense-in-depth methodologies for equipment availability.A general discussion of these areas is provided below. Specific details ofthe findings are contained in the inspection reports referenced above.Risk Assessment for Pre-Outage Planning, Emergent Work and Schedule ChangesThe inspectors found that licensees used various programmatic controls toassess shutdown risk factors during initial outage planning, emergent work andschedule changes. Assessment methodologies used for initial outage planningranged from following minimum guidelines for equipment availability toperforming a probabilistic risk assessment of scheduled outage activities.The inspection team found that the risk assessment aided the licensee inidentifying activities that would be subject to high risk during the sched ledoutage. However, as the outage progressed, the risk assessment became lessvalid because it was not updated as changes to the outage schedule occurredaIn the areas of emergent work and schedule changes, the inspectors found thatthree of the plants had a proceduralized process to assess the effect of \emergent work or schedule changes on plant risk. The other two plants reliedon a functional review by planners, schedulers, and operators to adjust theschedule appropriately to reduce risk.The inspectors found that all of the plants maintained status boards orchecklists in the control room to assist the operators in tracking theconfiguration status of plant systems and to help identify potentialrisk-significant activities.Implementation of Defense-in-Depth for Equipment AvailabilityThe inspection teams found that licensee implementation of defense-in-depthfor equipment availability was inconsistent. Although industry guidelines fordeclaring equipment "available" exist, the inspectors found that the criteriafor declaring equipment needed to ensure an appropriate margin of safety"available" varied from licensee to licensee. For example, declaring thatequipment was "available" did not always include ensuring that support systems(e.g., cooling water and heating, ventilation and air conditioning) were alsoavailable. At times, after maintenance had been performed, equipment waslisted as "available" without the benefit of a post-maintenance functionaltest. The inspectors also found that some equipment was considered to be"available" even though actions, such as removal of clearances or realignmentof valves, would be required before the equipment could perform its function.In addition to the above concerns, at most of the plants the team inspectorsfound examples of failures to comply with technical specification restrictionson overtime work in that management approval to exceed overtime limits wasinadequately documented.
Bypassed 09/13/93 09/10/93 09/02/93 09/01/93 08/23/93 08/16/93 08/16/93 08/13/93 All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors and all radiography


K-,This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:J.D. Wilcox, NRR(301) 504-1262Attachment: List of Recently Issued NRC Information NoticesRSIB:DRIL:NRRJDWilcox07/02/93RPB:ADMNBeeson08/10/93RSIB:DRIL:NRRSSanders07/02/93OGCB:DORS:NRRJLBirmingham08 /1/ 93 J9AC/RSIB:DRIL:NRRDNorkin07/02/93C70MO:DORS:NRRiGHMarcusPT ;S/Al/93D/DRIL:NRRCERossi07/10/93D/DORS:NRRBKGrimes09/ /93RSIB:DRIL:NRRPSKoltay07/06/93
licensees.
-IN 93-xxSeptember xx, 1993 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:J.D. Wilcox, NRR(301) 504-1262Attachment:List of Recently Issued NRC Information Notices*SEE PREVIOUS CONCURRENCE*RSIB:DRIL:NRR *RSIB:DRIL:NRRJDWilcox SSanders07/02/93 07/02/93*AC/RSIB:DRIL:NRRDNorkin07/02/93> C/OGCB:DORS:NRRGHMarcus/Wen08/27/93*D/DRIL:NRRCERossi07/10/93D/DORS:NRRBKGrimes09/ /93*RPB:ADMNBeeson08/10/93*OGCB:DORS:NRRJLBirmingham08/27/93*RSIB:DRIL:NRRPSKoltay07/06/93DOCUMENT NAME:OUTAGEIN.JLB


'-vJIN 93-72September 14, 993Based on the five pilot inspections, the NRC inspection teams concluded thatNRC actions and industry initiatives have increased licensee awareness of therisk associated with shutdown and low power conditions. The inspection teamsfound that licensees were aware of the necessity for ensuring that requiredsystems be available and of the need to maintain the capability of backupequipment during an outage. However, the inspection teams found that licenseeinterpretations of industry initiatives for addressing shutdown risk variedgreatly. This was demonstrated by the various licensee interpretations ofindustry guidelines for declaring equipment "available."This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Original signed byBrian K. GrimesBrian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:J.D. Wilcox, NRR(301) 504-1262Attachment:List of Recently Issued NRC Information Notices*SEE PREVIOUS CONCURRENCE*RSIB:DRIL:NRR *RSIB:DRIL:NRRJDWilcox SSanders07/02/93 07/02/93*AC/RSIB:DRIL:NRRDNorkin07/02/93*C/OGCB:DORS:NRRGHMarcus/Wen08/27/93*D/DRIL:NRRCERossi07/1 dJ3 (qy*RPB:ADMNBeeson08/10/93*OGCB:DORS:NRRJLBirmingham08/27/93*RSIB:DRIL:NRRPSKoltay07/06/93DOCUMENT NAME: 93-72.IN
All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for pressurized


IN 93-72September 14, 1993 Based on the five pilot inspections, the NRC inspection teams concluded thatNRC actions and industry initiatives have increased licensee awareness of therisk associated with shutdown and low power conditions. The inspection teamsfound that licensees were aware of the necessity for ensuring that requiredsystems be available and of the need to maintain the capability of backupequipment during an outage. However, the inspection teams found that licenseeinterpretations of industry initiatives for addressing shutdown risk variedgreatly. This was demonstrated by the various licensee interpretations ofindustry guidelines for declaring equipment "available."This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.C-Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact: J.D. Wilcox, NRR(301) 504-1262Attachment:List of Recently Issued NRC Information Notices
water reactors.All holders of OLs or CPs for nuclear power reactors.OL = Operating


KJAttachmentIN 93-72September 14, 1993 LIST OF RECENTLY ISSUEDNRC INFORMATION NOTICESInformation Date ofNotice No. Subject Issuance Issued to93-7193-7093-6993-6892-16,Supp. 293-6793-6693-65Fire at Chernobyl Unit 2Degradation of BoraflexNeutron Absorber CouponsRadiography Events atOperating Power ReactorsFailure of Pump ShaftCoupling Caused byTemper Embrittlementduring ManufactureLoss of Flow from theResidual Heat RemovalPump during RefuelingCavity DraindownBursting of HighPressure CoolantInjection Steam LineRupture Discs InjuresPlant PersonnelSwitchover to Hot-LegInjection FollowingA Loss-of-CoolantAccident in Pres-surized Water ReactorsReactor Trips Causedby Breaker Testingwith Fault ProtectionBypassed09/13/9309/10/9309/02/9309/01/9308/23/9308/16/9308/16/9308/13/93All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactorsand all radiographylicensees.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor pressurized waterreactors.All holders of OLs or CPsfor nuclear power reactors.OL = Operating LicenseCP = Construction Permit
License CP = Construction


}}
Permit}}


{{Information notice-Nav}}
{{Information notice-Nav}}

Revision as of 13:56, 31 August 2018

Observations from Recent Shutdown Risk and Outage Management Pilot Team Inspections
ML031070092
Person / Time
Site: Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant  Entergy icon.png
Issue date: 09/14/1993
From: Grimes B K
Office of Nuclear Reactor Regulation
To:
References
IN-93-072, NUDOCS 9309090243
Download: ML031070092 (8)
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Ku UNITED STATES NUCLEAR REGULATORY

COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555 September

14, 1993 NRC INFORMATION

NOTICE 93-72: OBSERVATIONS

FROM RECENT SHUTDOWN RISK AND OUTAGE MANAGEMENT

PILOT TEAM INSPECTIONS

Addressees

All holders of operating

licenses or construction

permits for nuclear power reactors.

Purpose

The U.S. Nuclear Regulatory

Commission (NRC) is issuing this information

notice to inform addressees

of observations

from recent shutdown risk and outage management

pilot team inspections.

It is expected that recipients

will review the information

for applicability

to their facilities

and consider actions, as appropriate, to avoid similar problems.

However, suggestions

contained

in this information

notice are not NRC requirements;

therefore, no specific action or written response is required.Background

Events that occurred during the past several years have caused the NRC staff to be increasingly

concerned

about plant safety during shutdown operations.

The Diablo Canyon event of April 10, 1987, in which boiling of the reactor coolant resulted from a loss of decay heat removal, highlighted

the fact that operation

of a pressurized-water

reactor with a reduced reactor coolant system (RCS) inventory

is a particularly

sensitive

condition.

Based on its review of that event, the staff issued Generic Letter 88-17, "Loss of Decay Heat Removal," October 17, 1988, which requested

that licensees

address certain generic deficiencies

to improve safety during operations

with a reduced RCS inventory.

More recently, Incident Investigation

Team report, NUREG-1410,"Loss of Vital ac Power and the Residual Heat Removal System During Mid-Loop Operations

at Plant Vogtle Unit 1 on March 20, 1990," emphasized

the need for risk management

of shutdown operations.

Discussions

with foreign regulatory

organizations

support NRC staff findings that the core-damage-frequency

for shutdown operations

may be a substantial

fraction of the total core-damage

frequency.

Description

of Circumstances

Between December 1991 and April 1993, the NRC staff conducted

five pilot team inspections

to assess the effectiveness

of industry initiatives

for improving shutdown safety. The inspections

were performed

at Oconee Nuclear Station, Unit 2 [NRC Inspection

Report (IR) 50-270/91-202], Indian Point Nuclear 9309090243

-U 1?-.crn-9

.3 IN 93-72 September

14, 1993 Generating

Station, Unit 3 (IR 50-286/92-901), Diablo Canyon Nuclear Station, Unit 1 (IR 50-275/92-201), Prairie Island Nuclear Generating

Plant, Units 1 and 2 (IR 50-282/92-201;

50-306/92-201), and Cooper Nuclear Station (IR 50-298/93-201).

Approximately

one week of each inspection

focused on licensee pre-outage

planning and control processes

and 8 to 10 days focused on licensee implementation

of the outage.In the pre-outage

portion of the inspection, the inspectors

evaluated

the following:

(1) management

involvement

in and oversight

of the outage planning process, (2) planning and scheduling

of outage activities, especially

the relationships

between significant

work activities

and the availability

of electrical

power supplies, decay heat removal systems, reactor coolant system RCS inventory

and containment

integrity, (3) the process for developing

individual

work packages to ensure coordination

with other activities, and (4)operator response procedures, contingency

plans and training for mitigation

of loss of decay heat removal capability, loss of RCS inventory

and loss of electrical

power sources during shutdown conditions.

The inspectors

walked through procedures

related to shutdown safety to determine

if the specified

activities

could be accomplished

in the allotted time frames and to verify that the procedures

could be implemented

considering

probable equipment

availability.

The inspectors

reviewed training records on outage procedures

to determine

if the training was adequate and that, when appropriate, additional

training was provided as the procedures

were revised.The inspectors

also evaluated

the probable effects of environmental

conditions

such as temperature, steam and flooding on the performance

of activities

that would be required to mitigate adverse shutdown events.In the implementation

portion of the inspection, the inspectors

evaluated:

(1) the control of changes to the outage schedule, control of work activities, and control of system alignments, (2) the working relationships

and communication

channels between operations, maintenance

and other plant support personnel, (3) the conduct of operations

personnel

both inside and outside of the control room regarding

awareness

of plant status, control of plant evolutions, response to alarms and other abnormal indications, (4) the completeness

and effectiveness

of shift turnovers, (5) whether maintenance

and modification

work was performed

in accordance

with current written and approved procedures

and appropriate

post-maintenance

testing was required and performed, and (6) the adequacy of management

involvement

and oversight

of the conduct of the outage as it progressed.

Other areas observed were, plant housekeeping, normal and emergency

plant lighting, configuration

control, radiological

controls, equipment

labeling and status tagging, vital area access control, use of overtime and licensee control of contractor

work including

contractor

training and qualifications.

Discussion

In general, the inspectors

found that licensees

had instituted

programmatic

changes developed

from guidance contained

in a Nuclear Management

and Resources

Council document, NUMARC 91-06, "Guidelines

for Industry Actions to

TV IN 93-72 September

14, 1993 Assess Shutdown Management." The team inspectors

found individual

examples of licensee failure to follow procedures

but more importantly

the inspectors

identified

two areas of more general concern: (1) risk assessment

for pre-outage

planning, emergent work and schedule changes, and (2)implementation

of defense-in-depth

methodologies

for equipment

availability.

A general discussion

of these areas is provided below. Specific details of the findings are contained

in the inspection

reports referenced

above.Risk Assessment

for Pre-Outage

Planning, Emergent Work and Schedule Changes The inspectors

found that licensees

used various programmatic

controls to assess shutdown risk factors during initial outage planning, emergent work and schedule changes. Assessment

methodologies

used for initial outage planning ranged from following

minimum guidelines

for equipment

availability

to performing

a probabilistic

risk assessment

of scheduled

outage activities.

The inspection

team found that the risk assessment

aided the licensee in identifying

activities

that would be subject to high risk during the sched led outage. However, as the outage progressed, the risk assessment

became less valid because it was not updated as changes to the outage schedule occurreda In the areas of emergent work and schedule changes, the inspectors

found that three of the plants had a proceduralized

process to assess the effect of \emergent work or schedule changes on plant risk. The other two plants relied on a functional

review by planners, schedulers, and operators

to adjust the schedule appropriately

to reduce risk.The inspectors

found that all of the plants maintained

status boards or checklists

in the control room to assist the operators

in tracking the configuration

status of plant systems and to help identify potential risk-significant

activities.

Implementation

of Defense-in-Depth

for Equipment

Availability

The inspection

teams found that licensee implementation

of defense-in-depth

for equipment

availability

was inconsistent.

Although industry guidelines

for declaring

equipment "available" exist, the inspectors

found that the criteria for declaring

equipment

needed to ensure an appropriate

margin of safety"available" varied from licensee to licensee.

For example, declaring

that equipment

was "available" did not always include ensuring that support systems (e.g., cooling water and heating, ventilation

and air conditioning)

were also available.

At times, after maintenance

had been performed, equipment

was listed as "available" without the benefit of a post-maintenance

functional

test. The inspectors

also found that some equipment

was considered

to be"available" even though actions, such as removal of clearances

or realignment

of valves, would be required before the equipment

could perform its function.In addition to the above concerns, at most of the plants the team inspectors

found examples of failures to comply with technical

specification

restrictions

on overtime work in that management

approval to exceed overtime limits was inadequately

documented.

K-, This information

notice requires no specific action or written response.

If you have any questions

about the information

in this notice, please contact the technical

contact listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.Brian K. Grimes, Director Division of Operating

Reactor Support Office of Nuclear Reactor Regulation

Technical

contact: J.D. Wilcox, NRR (301) 504-1262 Attachment:

List of Recently Issued NRC Information

Notices RSIB:DRIL:NRR

JDWilcox 07/02/93 RPB:ADM NBeeson 08/10/93 RSIB:DRIL:NRR

SSanders 07/02/93 OGCB:DORS:NRR

JLBirmingham

08 /1/ 93 J9 AC/RSIB:DRIL:NRR

DNorkin 07/02/93 C70MO:DORS:NRR

iGHMarcus PT ;S/Al/93 D/DRIL:NRR

CERossi 07/10/93 D/DORS:NRR

BKGrimes 09/ /93 RSIB:DRIL:NRR

PSKoltay 07/06/93

-IN 93-xx September

xx, 1993 This information

notice requires no specific action or written response.

If you have any questions

about the information

in this notice, please contact the technical

contact listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.Brian K. Grimes, Director Division of Operating

Reactor Support Office of Nuclear Reactor Regulation

Technical

contact: J.D. Wilcox, NRR (301) 504-1262 Attachment:

List of Recently Issued NRC Information

Notices*SEE PREVIOUS CONCURRENCE

  • RSIB:DRIL:NRR
  • RSIB:DRIL:NRR

JDWilcox SSanders 07/02/93 07/02/93*AC/RSIB:DRIL:NRR

DNorkin 07/02/93> C/OGCB:DORS:NRR

GHMarcus/Wen

08/27/93*D/DRIL:NRR

CERossi 07/10/93 D/DORS:NRR

BKGrimes 09/ /93*RPB:ADM NBeeson 08/10/93*OGCB:DORS:NRR

JLBirmingham

08/27/93*RSIB:DRIL:NRR

PSKoltay 07/06/93 DOCUMENT NAME: OUTAGEIN.JLB

'-vJ IN 93-72 September

14, 1993 Based on the five pilot inspections, the NRC inspection

teams concluded

that NRC actions and industry initiatives

have increased

licensee awareness

of the risk associated

with shutdown and low power conditions.

The inspection

teams found that licensees

were aware of the necessity

for ensuring that required systems be available

and of the need to maintain the capability

of backup equipment

during an outage. However, the inspection

teams found that licensee interpretations

of industry initiatives

for addressing

shutdown risk varied greatly. This was demonstrated

by the various licensee interpretations

of industry guidelines

for declaring

equipment "available." This information

notice requires no specific action or written response.

If you have any questions

about the information

in this notice, please contact the technical

contact listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.Original signed by Brian K. Grimes Brian K. Grimes, Director Division of Operating

Reactor Support Office of Nuclear Reactor Regulation

Technical

contact: J.D. Wilcox, NRR (301) 504-1262 Attachment:

List of Recently Issued NRC Information

Notices*SEE PREVIOUS CONCURRENCE

  • RSIB:DRIL:NRR
  • RSIB:DRIL:NRR

JDWilcox SSanders 07/02/93 07/02/93*AC/RSIB:DRIL:NRR

DNorkin 07/02/93*C/OGCB:DORS:NRR

GHMarcus/Wen

08/27/93*D/DRIL:NRR

CERossi 07/1 dJ3 (qy*RPB:ADM NBeeson 08/10/93*OGCB:DORS:NRR

JLBirmingham

08/27/93*RSIB:DRIL:NRR

PSKoltay 07/06/93 DOCUMENT NAME: 93-72.IN

IN 93-72 September

14, 1993 Based on the five pilot inspections, the NRC inspection

teams concluded

that NRC actions and industry initiatives

have increased

licensee awareness

of the risk associated

with shutdown and low power conditions.

The inspection

teams found that licensees

were aware of the necessity

for ensuring that required systems be available

and of the need to maintain the capability

of backup equipment

during an outage. However, the inspection

teams found that licensee interpretations

of industry initiatives

for addressing

shutdown risk varied greatly. This was demonstrated

by the various licensee interpretations

of industry guidelines

for declaring

equipment "available." This information

notice requires no specific action or written response.

If you have any questions

about the information

in this notice, please contact the technical

contact listed below or the appropriate

Office of Nuclear Reactor Regulation (NRR) project manager.C-Brian K. Grimes, Director Division of Operating

Reactor Support Office of Nuclear Reactor Regulation

Technical

contact: J.D. Wilcox, NRR (301) 504-1262 Attachment:

List of Recently Issued NRC Information

Notices

KJ Attachment

IN 93-72 September

14, 1993 LIST OF RECENTLY ISSUED NRC INFORMATION

NOTICES Information

Date of Notice No. Subject Issuance Issued to 93-71 93-70 93-69 93-68 92-16, Supp. 2 93-67 93-66 93-65 Fire at Chernobyl

Unit 2 Degradation

of Boraflex Neutron Absorber Coupons Radiography

Events at Operating

Power Reactors Failure of Pump Shaft Coupling Caused by Temper Embrittlement

during Manufacture

Loss of Flow from the Residual Heat Removal Pump during Refueling Cavity Draindown Bursting of High Pressure Coolant Injection

Steam Line Rupture Discs Injures Plant Personnel Switchover

to Hot-Leg Injection

Following A Loss-of-Coolant

Accident in Pres-surized Water Reactors Reactor Trips Caused by Breaker Testing with Fault Protection

Bypassed 09/13/93 09/10/93 09/02/93 09/01/93 08/23/93 08/16/93 08/16/93 08/13/93 All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors and all radiography

licensees.

All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for pressurized

water reactors.All holders of OLs or CPs for nuclear power reactors.OL = Operating

License CP = Construction

Permit


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