Information Notice 1993-72, Observations from Recent Shutdown Risk and Outage Management Pilot Team Inspections: Difference between revisions

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| issue date = 09/14/1993
| issue date = 09/14/1993
| title = Observations from Recent Shutdown Risk and Outage Management Pilot Team Inspections
| title = Observations from Recent Shutdown Risk and Outage Management Pilot Team Inspections
| author name = Grimes B K
| author name = Grimes B
| author affiliation = NRC/NRR
| author affiliation = NRC/NRR
| addressee name =  
| addressee name =  
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| page count = 8
| page count = 8
}}
}}
{{#Wiki_filter:Ku UNITED STATES NUCLEAR REGULATORY
{{#Wiki_filter:Ku


COMMISSION
UNITED STATES


===OFFICE OF NUCLEAR REACTOR REGULATION===
NUCLEAR REGULATORY COMMISSION
WASHINGTON, D.C. 20555 September


14, 1993 NRC INFORMATION
OFFICE OF NUCLEAR REACTOR REGULATION


NOTICE 93-72: OBSERVATIONS
WASHINGTON, D.C. 20555 September 14, 1993 NRC INFORMATION NOTICE 93-72:   OBSERVATIONS FROM RECENT SHUTDOWN RISK AND


FROM RECENT SHUTDOWN RISK AND OUTAGE MANAGEMENT
OUTAGE MANAGEMENT PILOT TEAM INSPECTIONS
 
===PILOT TEAM INSPECTIONS===


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


licenses or construction
reactors.
 
permits for nuclear power reactors.


==Purpose==
==Purpose==
The U.S. Nuclear Regulatory
The U.S. Nuclear Regulatory Commission (NRC) is issuing this information


Commission (NRC) is issuing this information
notice to inform addressees of observations from recent shutdown risk and


notice to inform addressees
outage management pilot team inspections. It is expected that recipients will


of observations
review the information for applicability to their facilities and consider


from recent shutdown risk and outage management
actions, as appropriate, to avoid similar problems. However, suggestions


pilot team inspections.
contained in this information notice are not NRC requirements; therefore, no


It is expected that recipients
specific action or written response is required.


will review the information
Background


for applicability
Events that occurred during the past several years have caused the NRC staff


to their facilities
to be increasingly concerned about plant safety during shutdown operations.


and consider actions, as appropriate, to avoid similar problems.
The Diablo Canyon event of April 10, 1987, in which boiling of the reactor


===However, suggestions===
coolant resulted from a loss of decay heat removal, highlighted the fact that
contained


in this information
operation of a pressurized-water reactor with a reduced reactor coolant system


notice are not NRC requirements;
(RCS) inventory is a particularly sensitive condition. Based on its review of
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
that event, the staff issued Generic Letter 88-17, "Loss of Decay Heat


concerned
Removal," October 17, 1988, which requested that licensees address certain


about plant safety during shutdown operations.
generic deficiencies to improve safety during operations with a reduced RCS


The Diablo Canyon event of April 10, 1987, in which boiling of the reactor coolant resulted from a loss of decay heat removal, highlighted
inventory. More recently, Incident Investigation Team report, NUREG-1410,
"Loss of Vital ac Power and the Residual Heat Removal System During Mid-Loop


the fact that operation
Operations at Plant Vogtle Unit 1 on March 20, 1990," emphasized the need for


of a pressurized-water
risk management of shutdown operations. Discussions with foreign regulatory


reactor with a reduced reactor coolant system (RCS) inventory
organizations support NRC staff findings that the core-damage-frequency for


is a particularly
shutdown operations may be a substantial fraction of the total core-damage
 
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.
frequency.


Description
==Description of Circumstances==
 
Between December 1991 and April 1993, the NRC staff conducted five pilot team
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;
inspections to assess the effectiveness of industry initiatives for improving
50-306/92-201), and Cooper Nuclear Station (IR 50-298/93-201).


Approximately
shutdown safety. The inspections were performed at Oconee Nuclear Station, Unit 2 [NRC Inspection Report (IR)50-270/91-202], Indian Point Nuclear


one week of each inspection
9309090243
                      -          U              1?-.crn-9
                                                    3                  .


focused on licensee pre-outage
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


planning and control processes
(IR 50-298/93-201). Approximately one week of each inspection focused on


and 8 to 10 days focused on licensee implementation
licensee pre-outage planning and control processes and 8 to 10 days focused on


of the outage.In the pre-outage
licensee implementation of the outage.


portion of the inspection, the inspectors
In the pre-outage portion of the inspection, the inspectors evaluated the


evaluated
following: (1) management involvement in and oversight of the outage planning


the following:
process, (2) planning and scheduling of outage activities, especially the
(1) management


involvement
relationships between significant work activities and the availability of


in and oversight
electrical power supplies, decay heat removal systems, reactor coolant system


of the outage planning process, (2) planning and scheduling
RCS inventory and containment integrity, (3) the process for developing


of outage activities, especially
individual work packages to ensure coordination with other activities, and (4)
operator response procedures, contingency plans and training for mitigation of


the relationships
loss of decay heat removal capability, loss of RCS inventory and loss of


between significant
electrical power sources during shutdown conditions.


work activities
The inspectors walked through procedures related to shutdown safety to


and the availability
determine if the specified activities could be accomplished in the allotted


of electrical
time frames and to verify that the procedures could be implemented considering


power supplies, decay heat removal systems, reactor coolant system RCS inventory
probable equipment availability. The inspectors reviewed training records on


and containment
outage procedures to determine if the training was adequate and that, when


integrity, (3) the process for developing
appropriate, additional training was provided as the procedures were revised.


individual
The inspectors also evaluated the probable effects of environmental conditions


work packages to ensure coordination
such as temperature, steam and flooding on the performance of activities that


with other activities, and (4)operator response procedures, contingency
would be required to mitigate adverse shutdown events.


plans and training for mitigation
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


of loss of decay heat removal capability, loss of RCS inventory
communication channels between operations, maintenance and other plant support


and loss of electrical
personnel, (3) the conduct of operations personnel both inside and outside of


power sources during shutdown conditions.
the control room regarding awareness of plant status, control of plant


The inspectors
evolutions, response to alarms and other abnormal indications, (4) the


walked through procedures
completeness and effectiveness of shift turnovers, (5) whether maintenance and


related to shutdown safety to determine
modification work was performed in accordance with current written and


if the specified
approved procedures and appropriate post-maintenance testing was required and


activities
performed, and (6) the adequacy of management involvement and oversight of the


could be accomplished
conduct of the outage as it progressed.


in the allotted time frames and to verify that the procedures
Other areas observed were, plant housekeeping, normal and emergency plant


could be implemented
lighting, configuration control, radiological controls, equipment labeling and


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


probable equipment
control of contractor work including contractor training and qualifications.
 
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
Discussion


In general, the inspectors
In general, the inspectors found that licensees had instituted programmatic
 
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
changes developed from guidance contained in a Nuclear Management and


for Pre-Outage
Resources Council document, NUMARC 91-06, "Guidelines for Industry Actions to


Planning, Emergent Work and Schedule Changes The inspectors
TV


found that licensees
IN 93-72 September 14, 1993 individual examples of


used various programmatic
Assess Shutdown Management." The team inspectors found                the inspectors


controls to assess shutdown risk factors during initial outage planning, emergent work and schedule changes. Assessment
licensee failure to follow procedures but more importantly        assessment      for


methodologies
identified two areas of more  general  concern:      (1)  risk


used for initial outage planning ranged from following
and (2)
pre-outage planning, emergent work and schedule changes,                    availability.


minimum guidelines
methodologies    for  equipment


for equipment
implementation of defense-in-depth                                Specific    details of


availability
A general discussion of these  areas  is provided    below.


to performing
above.


a probabilistic
the findings are contained in the inspection reports referenced


risk assessment
and Schedule Changes


of scheduled
Risk Assessment for Pre-Outage Planning, Emergent Work


outage activities.
controls to


The inspection
The inspectors found that licensees used various programmatic            emergent    work and


team found that the risk assessment
assess shutdown risk factors during initial outage planning, outage planning


aided the licensee in identifying
schedule changes. Assessment methodologies used for initial    availability to


activities
ranged from following minimum guidelines for equipment outage activities.


that would be subject to high risk during the sched led outage. However, as the outage progressed, the risk assessment
performing a probabilistic risk assessment of scheduled            the licensee in


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
The inspection team found that the risk assessment aided during the sched led


found that three of the plants had a proceduralized
identifying activities that would be subject to high risk                    became less


process to assess the effect of \emergent work or schedule changes on plant risk. The other two plants relied on a functional
outage. However, as the outage progressed, the risk assessment      schedule     occurreda


review by planners, schedulers, and operators
valid because it was not updated as changes to the outage


to adjust the schedule appropriately
inspectors found that


to reduce risk.The inspectors
In the areas of emergent work and schedule changes, the                    effect of      \
three of the plants had a proceduralized process to assess the          two  plants  relied


found that all of the plants maintained
other


status boards or checklists
emergent work or schedule changes on plant risk. Theoperators to adjust the


in the control room to assist the operators
on a functional review by planners, schedulers, and


in tracking the configuration
schedule appropriately to reduce risk.


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


activities.
The inspectors found that all of the plants maintained in tracking the


Implementation
checklists in the control room to assist the      operators


of Defense-in-Depth
potential


for Equipment
configuration status of plant systems and to help identify


===Availability===
risk-significant activities.
The inspection


teams found that licensee implementation
Implementation of Defense-in-Depth for Equipment Availability


of defense-in-depth
of defense-in-depth


for equipment
The inspection teams found that licensee implementation industry guidelines for
 
availability
 
was inconsistent.
 
Although industry guidelines
 
for declaring
 
equipment "available" exist, the inspectors
 
found that the criteria for declaring


equipment
for equipment availability was inconsistent.      Although


needed to ensure an appropriate
that the criteria


margin of safety"available" varied from licensee to licensee.
declaring equipment "available" exist, the inspectors found                of safety


For example, declaring
an  appropriate      margin


that equipment
for declaring equipment needed to ensure                                declaring    that


was "available" did not always include ensuring that support systems (e.g., cooling water and heating, ventilation
"available" varied from licensee to licensee.      For  example, include   ensuring     that   support   systems


and air conditioning)  
equipment was "available" did not always                      conditioning)       were also
were also available.


At times, after maintenance
(e.g., cooling water and heating, ventilation      and  air


had been performed, equipment
had been   performed,     equipment   was


was listed as "available" without the benefit of a post-maintenance
available. At times, after maintenance                                       functional


functional
listed as "available" without the benefit of a post-maintenance  considered      to be


test. The inspectors
test. The inspectors also found that    some  equipment    was


also found that some equipment
as  removal    of  clearances      or  realignment


was considered
"available" even though actions, such                            perform its function.


to be"available" even though actions, such as removal of clearances
of valves, would be required before the equipment could


or realignment
the team inspectors


of valves, would be required before the equipment
In addition to the above concerns, at most of the plants                        restrictions


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


found examples of failures to comply with technical
to exceed    overtime    limits  was


specification
on overtime work in that management approval


restrictions
inadequately documented.


on overtime work in that management
K-,
This information notice requires no specific action or written response. If


approval to exceed overtime limits was inadequately
you have any questions about the information in this notice, please contact


documented.
the technical contact listed below or the appropriate Office of Nuclear


K-, This information
Reactor Regulation (NRR) project manager.


notice requires no specific action or written response.
Brian K. Grimes, Director


If you have any questions
Division of Operating Reactor Support


about the information
Office of Nuclear Reactor Regulation


in this notice, please contact the technical
Technical contact:  J.D. Wilcox, NRR


contact listed below or the appropriate
(301) 504-1262 Attachment:  List of Recently Issued NRC Information Notices


Office of Nuclear Reactor Regulation (NRR) project manager.Brian K. Grimes, Director Division of Operating
RSIB:DRIL:NRR      RSIB:DRIL:NRR      AC/RSIB:DRIL:NRR  D/DRIL:NRR


===Reactor Support Office of Nuclear Reactor Regulation===
JDWilcox          SSanders            DNorkin          CERossi
Technical


contact: J.D. Wilcox, NRR (301) 504-1262 Attachment:
07/02/93          07/02/93            07/02/93          07/10/93 RPB:ADM            OGCB:DORS:NRR      C70MO:DORS:NRR    D/DORS:NRR
List of Recently Issued NRC Information


Notices RSIB:DRIL:NRR
NBeeson            JLBirmingham      iGHMarcus          BKGrimes


JDWilcox 07/02/93 RPB:ADM NBeeson 08/10/93 RSIB:DRIL:NRR
08/10/93           08 /1/ 93 J9        PT


SSanders 07/02/93 OGCB:DORS:NRR
;S/Al/93         09/ /93 RSIB:DRIL:NRR


===JLBirmingham===
PSKoltay
08 /1/ 93 J9 AC/RSIB:DRIL:NRR


DNorkin 07/02/93 C70MO:DORS:NRR
07/06/93


iGHMarcus PT ;S/Al/93 D/DRIL:NRR
-                                                              IN 93-xx


CERossi 07/10/93 D/DORS:NRR
September xx, 1993 This information notice requires no specific action or written response. If


BKGrimes 09/ /93 RSIB:DRIL:NRR
you have any questions about the information in this notice, please contact


PSKoltay 07/06/93
the technical contact listed below or the appropriate Office of Nuclear
-IN 93-xx September


xx, 1993 This information
Reactor Regulation (NRR) project manager.


notice requires no specific action or written response.
Brian K. Grimes, Director


If you have any questions
Division of Operating Reactor Support


about the information
Office of Nuclear Reactor Regulation


in this notice, please contact the technical
Technical contact:    J.D. Wilcox, NRR


contact listed below or the appropriate
(301) 504-1262 Attachment:    List of Recently Issued NRC Information Notices


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


===Reactor Support Office of Nuclear Reactor Regulation===
*RSIB:DRIL:NRR      *RSIB:DRIL:NRR    *AC/RSIB:DRIL:NRR *D/DRIL:NRR
Technical


contact: J.D. Wilcox, NRR (301) 504-1262 Attachment:
JDWilcox            SSanders          DNorkin          CERossi
List of Recently Issued NRC Information


Notices*SEE PREVIOUS CONCURRENCE
07/02/93            07/02/93          07/02/93          07/10/93
*RPB:ADM            *OGCB:DORS:NRR > C/OGCB:DORS:NRR    D/DORS:NRR


*RSIB:DRIL:NRR
NBeeson            JLBirmingham      GHMarcus/Wen      BKGrimes


08/10/93          08/27/93          08/27/93          09/ /93
*RSIB:DRIL:NRR
*RSIB:DRIL:NRR


JDWilcox SSanders 07/02/93 07/02/93*AC/RSIB:DRIL:NRR
PSKoltay
 
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
07/06/93 DOCUMENT NAME:  OUTAGEIN.JLB


of the risk associated
'-vJ


with shutdown and low power conditions.
IN 93-72 September 14, 1993 Based on the five pilot inspections, the NRC inspection teams concluded that


The inspection
NRC actions and industry initiatives have increased licensee awareness of the


teams found that licensees
risk associated with shutdown and low power conditions. The inspection teams


were aware of the necessity
found that licensees were aware of the necessity for ensuring that required


for ensuring that required systems be available
systems be available and of the need to maintain the capability of backup


and of the need to maintain the capability
equipment during an outage. However, the inspection teams found that licensee


of backup equipment
interpretations of industry initiatives for addressing shutdown risk varied


during an outage. However, the inspection
greatly. This was demonstrated by the various licensee interpretations of


teams found that licensee interpretations
industry guidelines for declaring equipment "available."
This information notice requires no specific action or written response. If


of industry initiatives
you have any questions about the information in this notice, please contact


for addressing
the technical contact listed below or the appropriate Office of Nuclear


shutdown risk varied greatly. This was demonstrated
Reactor Regulation (NRR) project manager.


by the various licensee interpretations
Original signed by


of industry guidelines
Brian K.Grimes


for declaring
Brian K. Grimes, Director


equipment "available." This information
Division of Operating Reactor Support


notice requires no specific action or written response.
Office of Nuclear Reactor Regulation


If you have any questions
Technical contact:  J.D. Wilcox, NRR


about the information
(301) 504-1262 Attachment:


in this notice, please contact the technical
===List of Recently Issued NRC Information Notices===
*SEE PREVIOUS CONCURRENCE


contact listed below or the appropriate
*RSIB:DRIL:NRR    *RSIB:DRIL:NRR    *AC/RSIB:DRIL:NRR *D/DRIL:NRR


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


===Reactor Support Office of Nuclear Reactor Regulation===
07/02/93          07/02/93          07/02/93                07/1 dJ3 (qy
Technical


contact: J.D. Wilcox, NRR (301) 504-1262 Attachment:
*RPB:ADM          *OGCB:DORS:NRR   *C/OGCB:DORS:NRR
List of Recently Issued NRC Information


Notices*SEE PREVIOUS CONCURRENCE
NBeeson          JLBirmingham      GHMarcus/Wen


08/10/93          08/27/93          08/27/93
*RSIB:DRIL:NRR
*RSIB:DRIL:NRR


*RSIB:DRIL:NRR
PSKoltay


JDWilcox SSanders 07/02/93 07/02/93*AC/RSIB:DRIL:NRR
07/06/93 DOCUMENT NAME:  93-72.IN


DNorkin 07/02/93*C/OGCB:DORS:NRR
IN 93-72 September 14, 1993 Based on the five pilot inspections, the NRC inspection teams concluded that


GHMarcus/Wen
NRC actions and industry initiatives have increased licensee awareness of the


08/27/93*D/DRIL:NRR
risk associated with shutdown and low power conditions. The inspection teams


CERossi 07/1 dJ3 (qy*RPB:ADM NBeeson 08/10/93*OGCB:DORS:NRR
found that licensees were aware of the necessity for ensuring that required


===JLBirmingham===
systems be available and of the need to maintain the capability of backup
08/27/93*RSIB:DRIL:NRR


PSKoltay 07/06/93 DOCUMENT NAME: 93-72.IN
equipment during an outage. However, the inspection teams found that licensee


IN 93-72 September
interpretations of industry initiatives for addressing shutdown risk varied


14, 1993 Based on the five pilot inspections, the NRC inspection
greatly. This was demonstrated by the various licensee interpretations of


teams concluded
industry guidelines for declaring equipment "available."
This information notice requires no specific action or written response. If


that NRC actions and industry initiatives
you have any questions about the information in this notice, please contact


have increased
the technical contact listed below or the appropriate Office of Nuclear


licensee awareness
Reactor Regulation (NRR) project manager.


of the risk associated
C-
                                    Brian K. Grimes, Director


with shutdown and low power conditions.
Division of Operating Reactor Support


The inspection
Office of Nuclear Reactor Regulation


teams found that licensees
Technical contact:  J.D. Wilcox, NRR


were aware of the necessity
(301) 504-1262 Attachment:


for ensuring that required systems be available
===List of Recently Issued NRC Information Notices===


and of the need to maintain the capability
KJ


of backup equipment
Attachment


during an outage. However, the inspection
IN 93-72 September 14, 1993 LIST OF RECENTLY ISSUED


teams found that licensee interpretations
NRC INFORMATION NOTICES


of industry initiatives
Information                                  Date of


for addressing
Notice No.            Subject                Issuance  Issued to


shutdown risk varied greatly. This was demonstrated
93-71          Fire at Chernobyl Unit 2      09/13/93  All holders of OLs or CPs


by the various licensee interpretations
for nuclear power reactors.


of industry guidelines
93-70          Degradation of Boraflex        09/10/93  All holders of OLs or CPs


for declaring
Neutron Absorber Coupons                  for nuclear power reactors.


equipment "available." This information
93-69          Radiography Events at          09/02/93  All holders of OLs or CPs


notice requires no specific action or written response.
Operating Power Reactors                  for nuclear power reactors


If you have any questions
and all radiography


about the information
licensees.


in this notice, please contact the technical
93-68          Failure of Pump Shaft          09/01/93  All holders of OLs or CPs


contact listed below or the appropriate
Coupling Caused by                        for nuclear power reactors.


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


===Reactor Support Office of Nuclear Reactor Regulation===
during Manufacture
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
92-16,         Loss of Flow from the          08/23/93  All holders of OLs or CPs


NOTICES Information
Supp. 2        Residual Heat Removal                    for nuclear power reactors.


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
Pump during Refueling


Unit 2 Degradation
Cavity Draindown


of Boraflex Neutron Absorber Coupons Radiography
93-67          Bursting of High              08/16/93  All holders of OLs or CPs


Events at Operating
Pressure Coolant                          for nuclear power reactors.


Power Reactors Failure of Pump Shaft Coupling Caused by Temper Embrittlement
Injection Steam Line


during Manufacture
Rupture Discs Injures


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


Steam Line Rupture Discs Injures Plant Personnel Switchover
93-66          Switchover to Hot-Leg          08/16/93  All holders of OLs or CPs


to Hot-Leg Injection
Injection Following                      for pressurized water


Following A Loss-of-Coolant
A Loss-of-Coolant                         reactors.


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


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
93-65          Reactor Trips Caused          08/13/93   All holders of OLs or CPs


licensees.
by Breaker Testing                        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 nuclear power reactors.All holders of OLs or CPs for pressurized
with Fault Protection


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


License CP = Construction
OL = Operating License


Permit}}
CP = Construction Permit}}


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

Latest revision as of 04:24, 24 November 2019

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
Office of Nuclear Reactor Regulation
To:
References
IN-93-072, NUDOCS 9309090243
Download: ML031070092 (8)
v • d • e


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 individual examples of

Assess Shutdown Management." The team inspectors found the inspectors

licensee failure to follow procedures but more importantly assessment for

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

and (2)

pre-outage planning, emergent work and schedule changes, availability.

methodologies for equipment

implementation of defense-in-depth Specific details of

A general discussion of these areas is provided below.

above.

the findings are contained in the inspection reports referenced

and Schedule Changes

Risk Assessment for Pre-Outage Planning, Emergent Work

controls to

The inspectors found that licensees used various programmatic emergent work and

assess shutdown risk factors during initial outage planning, outage planning

schedule changes. Assessment methodologies used for initial availability to

ranged from following minimum guidelines for equipment outage activities.

performing a probabilistic risk assessment of scheduled the licensee in

The inspection team found that the risk assessment aided during the sched led

identifying activities that would be subject to high risk became less

outage. However, as the outage progressed, the risk assessment schedule occurreda

valid because it was not updated as changes to the outage

inspectors found that

In the areas of emergent work and schedule changes, the effect of \

three of the plants had a proceduralized process to assess the two plants relied

other

emergent work or schedule changes on plant risk. Theoperators to adjust the

on a functional review by planners, schedulers, and

schedule appropriately to reduce risk.

status boards or

The inspectors found that all of the plants maintained in tracking the

checklists in the control room to assist the operators

potential

configuration status of plant systems and to help identify

risk-significant activities.

Implementation of Defense-in-Depth for Equipment Availability

of defense-in-depth

The inspection teams found that licensee implementation industry guidelines for

for equipment availability was inconsistent. Although

that the criteria

declaring equipment "available" exist, the inspectors found of safety

an appropriate margin

for declaring equipment needed to ensure declaring that

"available" varied from licensee to licensee. For example, include ensuring that support systems

equipment was "available" did not always conditioning) were also

(e.g., cooling water and heating, ventilation and air

had been performed, equipment was

available. At times, after maintenance functional

listed as "available" without the benefit of a post-maintenance considered to be

test. The inspectors also found that some equipment was

as removal of clearances or realignment

"available" even though actions, such perform its function.

of valves, would be required before the equipment could

the team inspectors

In addition to the above concerns, at most of the plants restrictions

found examples of failures to comply with technical specification

to exceed overtime limits was

on overtime work in that management approval

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 RSIB:DRIL:NRR AC/RSIB:DRIL:NRR D/DRIL:NRR

JDWilcox SSanders DNorkin CERossi

07/02/93 07/02/93 07/02/93 07/10/93 RPB:ADM OGCB:DORS:NRR C70MO:DORS:NRR D/DORS:NRR

NBeeson JLBirmingham iGHMarcus BKGrimes

08/10/93 08 /1/ 93 J9 PT

S/Al/93 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 *AC/RSIB:DRIL:NRR *D/DRIL:NRR

JDWilcox SSanders DNorkin CERossi

07/02/93 07/02/93 07/02/93 07/10/93

  • RPB:ADM *OGCB:DORS:NRR > C/OGCB:DORS:NRR D/DORS:NRR

NBeeson JLBirmingham GHMarcus/Wen BKGrimes

08/10/93 08/27/93 08/27/93 09/ /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 *AC/RSIB:DRIL:NRR *D/DRIL:NRR

JDWilcox SSanders DNorkin CERossi

07/02/93 07/02/93 07/02/93 07/1 dJ3 (qy

  • RPB:ADM *OGCB:DORS:NRR *C/OGCB:DORS:NRR

NBeeson JLBirmingham GHMarcus/Wen

08/10/93 08/27/93 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 Fire at Chernobyl Unit 2 09/13/93 All holders of OLs or CPs

for nuclear power reactors.

93-70 Degradation of Boraflex 09/10/93 All holders of OLs or CPs

Neutron Absorber Coupons for nuclear power reactors.

93-69 Radiography Events at 09/02/93 All holders of OLs or CPs

Operating Power Reactors for nuclear power reactors

and all radiography

licensees.

93-68 Failure of Pump Shaft 09/01/93 All holders of OLs or CPs

Coupling Caused by for nuclear power reactors.

Temper Embrittlement

during Manufacture

92-16, Loss of Flow from the 08/23/93 All holders of OLs or CPs

Supp. 2 Residual Heat Removal for nuclear power reactors.

Pump during Refueling

Cavity Draindown

93-67 Bursting of High 08/16/93 All holders of OLs or CPs

Pressure Coolant for nuclear power reactors.

Injection Steam Line

Rupture Discs Injures

Plant Personnel

93-66 Switchover to Hot-Leg 08/16/93 All holders of OLs or CPs

Injection Following for pressurized water

A Loss-of-Coolant reactors.

Accident in Pres- surized Water Reactors

93-65 Reactor Trips Caused 08/13/93 All holders of OLs or CPs

by Breaker Testing for nuclear power reactors.

with Fault Protection

Bypassed

OL = Operating License

CP = Construction Permit


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