ML17263A293
| ML17263A293 | |
| Person / Time | |
|---|---|
| Site: | Ginna |
| Issue date: | 05/13/1993 |
| From: | Lazarus W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML17263A291 | List: |
| References | |
| 50-244-93-06, 50-244-93-6, NUDOCS 9305240138 | |
| Download: ML17263A293 (20) | |
See also: IR 05000244/1993006
Text
U. S. NUCLEAR REGULATORY COMMISSION
REGION I
Inspection Report 50-244/93-06
License: DPR-18
Facility:
R. E. Ginna Nuclear Power Plant
Rochester
Gas and Electric Corporation (RG&E)
Inspection:
Inspectors:
Approved by:
March 10 through April22, 1993
T. A. Moslak, Senior Resident Inspector, Ginna
E. C. Knutson, Resident Inspector,.Ginna
~W~ /PD
W.
s,
'ef, Reactor Projects Section 3B
INSPECTION.SCOPE
Date
Plant operations, radiological controls, maintenance/surveillance,
security, engineering/
technical support, and safety assessment/quality
verification.
INSPECTION OVERVIEW
g~g~ %~
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shutdown, and plant condition changes,
including reduced inventory operations.
Operator
response
to failure of both source range nuclear instruments during reactor shutdown was
appropriate.
PORC provided effective oversight of plant operations through major outage
activities, as well as thorough assessment
and conservative guidance in response to off-
normal plant incidents.
d fgdg -,
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was the lowest in the plant's history and reflected effective integration of engineering support
to resolving ALARAissues.
A record low number of personnel contaminations for the
outage (95 cases) further demonstrated
conscientious application of routine health physics and
ALARApractices.
'n
n
il: Stem/disc separation
was discovered as an existing condition in
two valves during extensive refurbishment of the service water system; neither of these valve
failures resulted in loss of equipment function, service water cooling capability, or long-term
loss of service water redundancy.
A containment integrated leak=rate test was satisfactorily
completed.
A fire in the containment building occurred when hot slag from a nearby cutting
job ignited badly loaded roughing filters in the "C" containment recirculation fan.
Failure to
assess
the condition of the roughing filters represented
a shortcoming in the licensee's
maintenance program and is a violation of 10 CFR 50 Appendix B corrective action
requirements.
9305Z40138
930514
ADOCK 05000244
6
(OVERVIEW CONTINUED)
- Qg~ri: The blizzard of March 13-14, 1993 produced damage to the site perimeter fence
and intrusion detection system.
Appropriate compensatory
measures
were promptly
implemented and repairs were expeditiously completed.
r
n
r n;
The annual siren activation test was completed with 97 percent of
the sirens demonstrated
to be fully operational.
En in
rin /T hni: Video inspection of the reactor coolant pump internals
verified that a bolt, discovered
unattached in the reactor vessel during the 1990 refueling
outage, had come from the "A" reactor coolant pump diffuser adaptor ring.
TABLEOF CONTENTS
OVERVIEW
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TABLE OF CONTENTS
1.0
PLANT OPERATIONS (71707)..............; ..
1.1
Operational Experiences
1.2
Control ofOperations...................
1.3
Failure of Source Range Nuclear Instruments During
1.4
Control of Operations with Reduced Reactor Coolant
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Shutdown .....
System Inventory
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2.0
RADIOLOGICALCONTROLS (71707)........
2.1
Routine Observations ...............
2.2
Outage ALARAReview ...........-..
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3.0
4.0
MAINTENANCE/SURVEILLANCE(62703, 61726)
3.1
Outage Maintenance Summary
3.2
Service Water System Refurbishment
3.2.1
Failure of Valves 4669 and 4738
3.2.2
Desludging of Screen House ......
Surveillance Observations
Containment Integrated Leak Rate Test
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Pire Involving "D" Containment Recirculation
Containment Material Condition
3.3
3.4
3.5
3.6
SECURITY (71707)
4.1
Routine Observations ...............
4.2
Storm Damage to Site Perimeter Fence ....
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Fan Cooler ........
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5.0
(71707)
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'1Snen Test ...
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6.0
ENGINEERING/TECHNICALSUPPORT (71707, 92701)
6.1
Missing Reactor Coolant Pump Diffuser Bolt
6.2
Containment Recirculation Fan Cooler Replacements......
6.3
Safety Injection System Accumulator Drain Valves Seismic
Quallficatlon
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7.0
SAFETY ASSESSMEN'I'/QUALITY VERIFICATION(90712,
0500)
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7.1
Periodic Reports ........................
7.2
Licensee Event Reports....................
90713, 92701,
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8.0
ADMINISTRATIVE(71707, 30702, 94600)
8.1
Backshift and Deep Backshift Inspection
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ExitMeetings..........................
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DETAILS
1.0
PLANT OPERATIONS {71707)
1.1
Operational Experiences
At the beginning of the inspection period, the plant was operating at 89 percent power,
coasting down at approximately one percent per day to the start of the cycle 23 refueling
outage.
At 7:00 a.m. on March 12, 1993, shutdown for the outage commenced with a 10
percent per hour power reduction.
The main generator output breakers were opened at 2:09
p.m. and the main turbine was tripped at 2:14 p.m.
The reactor trip breakers were opened
at 2:30 p.m., March 12.
The plant entered cold shutdown mode at 6:48 a.m., March 13.
The blizzard of March 13-14 had no significant effect on the safety of plant operations.
The
reactor coolant system (RCS) was drained to mid-loop level on March 16 for installation of
steam generator nozzle dams in support of U-tube inspections and repairs.
A complete
reactor core off-load to the spent fuel pool was conducted to support service water system
refurbishment and reactor coolant pump inspections.
Core reload commenced on April 3 and
was completed on April 5.
Following completion of steam generator U-tube repairs, the
RCS was again drained to mid-loop level on April 8 for removal of steam generator nozzle
dams.
RCS filland vent was completed on April 18 and forced circulation was restored on
April21.
Heat input from the operating reactor coolant pump raised RCS heatup
temperatures
to just below 350'F to support RCS hydrostatic testing.
This test was
completed on April22. At the close of the inspection period the licensee was preparing to
continue plant heatup to normal operating temperature for completion of testing prior to
reactor startup.
1.2
Control of Operations
Overall, the inspectors found the R. E. Ginna Nuclear Power plant to be operated safely.
Control room staffing was as required;-
Operators exercised control over access to the
.
control room.
Shift supervisors consistently maintained authority over activities and provided
detailed turnover briefings to relief crews.
Operators adhered to approved procedures
and
were knowledgeable of off-normal plant conditions.
The inspectors reviewed control room
log books for activities and trends, observed recorder traces for abnormalities,
assessed
compliance with technical specifications, and verified equipment availability was consistent
with the requirements for existing plant conditions.
During normal work hours and on
backshifts, accessible
areas of the plant were toured.
No operational inadequacies or
- concerns mere identified.
Several management initiatives were implemented during the 1993 outage to improve the
overall control of maintenance/modification
activities.
These included establishing a work
control center (WCS) outside of the control room for carrying out mechanical/electrical
isolation work area boundaries for the various jobs.
The.WCS was maiiaged by a Work
Control Supervisor {a licensed senior reactor operator) with a supporting staff of licensed
reactor operators and auxiliary operators to set and maintain plant configuration.
Final
authorization for requested
actions was by the control room Shift Superv'isor prior to
implementation to provide an added check to assure that the safety of an on-going task would
not be compromised by a requested configuration change.
The shifting of switching/tagging
responsibilities away from the control room to the WCS decreased
the volume of control
room traffic and accompanying distractions to the on-shift control room staff.
The insp'ector
concluded that these administrative changes
enhanced
the overall coordination of outage
activities and plant safety.
Throughout the outage period, frequent Plant Operations Review Committee (PORC)
meetings were held to assess
the safety and regulatory significance of off-normal plant
incidents, the turnover status of plant modifications, and plant readiness for startup.
Strong
management oversight was demonstrated
in the control of plant activities.
1.3
Failure of Source Range Nuclear Instruments During Shutdown
The principle measure of reactor power is derived from neutron flux immediately outside of=
the reactor vessel.
Since neutron flux is directly proportional to the rate of nuclear fission,
this provides real-time indication of reactor power for operational control as well as for the
automatic reactor protection system.
The level of neutron flux varies greatly (approximately
10 orders of magnitude) between shutdown and full power operations.
Because the range of
power is so large, different neutron detection mechanisms
must be employed to cover the full
range of reactor power; a detector that is sensitive enough to monitor shutdown neutron
levels becomes
saturated when the reactor is at power, while a detector that is rugged enough
to operate in the heavy neutron flux present during power operations lacks sensitivity at low
reactor power.
Excore nuclear instruments use three types of detectors,
and reactor power
is, by convention, considered in terms of the three corresponding instrument ranges:
1) the
source range (so called because
the neutron population consists of neutrons originating from
the source fissionable material); 2) the intermediate range; and, 3) the power range.
To
ensure continuity of indication as well as to provide an operability cross-check,
the
intermediate range overlaps both the source and power ra'nge.
To avoid detector saturation
and resultant damage due to high neutron and gamma flux, power is only applied to the
source range detectors when reactor power is within the range of the instruments; this occurs
automatically when reactor power is low in the intermediate range.
During the reactor shutdown on March 12, 1993, the two source range nuclear instruments
(SRNIs) failed to indicate power level when reactor power reached the automatic energization
(P-6) setpoint.
Operators attempted to manually energize the SRNIs, but this had no effect.
The reactor shutdown continued in parallel with these events and reactor power decreased
below the indicating range of the intermediate range nuclear instruments at 2:25 p.m.; from
this point until the reactor trip breakers were opened at 2:30 p.m., the plant was operating
with control rods latched and with no immediate indication of reactor power.
Operators then
stabilized plant conditions in hot shutdown rather than to proceed immediately with plant
cooldown.
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Technical specification (TS) 3.5.1.1 requires that the SRNIs be operable when reactor power
is in the source range, the reactor trip breakers are closed, and the control rod drive system
is capable of rod withdrawal.
Although allowance is made for operation with a single SRNI
(TS table 3.5-1, action statement (4)), operation with no SRNIs is not specifically addressed.
For such conditions, TS 3.0.1 applies and requires that the reactor be shutdown within one
hour.
Beyond satisfying this requirement, the inspector considered that licensee response
to
the situation was appropriate for the following reasons:
Reactor shutdown was in progress in accordance with operations procedure 0-2.1,
"Normal Shutdown to Hot Shutdown."
At the point in this procedure that the SRNIs
energize, most control rods have been almost fully inserted into the core; with no
cooldown in progress and the remaining rods continuing to be inserted, this
provided adequate
The TS concern for having SRNI indication while the control rod drive system is
capable of rod withdrawal (that is, the reactor trip'reakers are shut) is to provide,
indication of criticality; in the case of a control rod drive system malfunction, an
inadvertent criticality due to uncontrolled rod withdrawal.
However, the control rod
position indication system was operable during all subsequent control rod
manipulations and confirmed that only inward rod motion was occurring.
RCS boration in preparation for refueling was in progress,
thereby increasing
The SRNIs provide no automatic reactor protective actions that are required for
reactor safety, and the remainder of the reactor protection system was operable
throughout the event; therefore, independent of the above-listed factors, reactor safety
was not compromised by loss of the SRNIs.
The Plant Operations Review Committee (PORC) immediately convened to review the event
and to develop guidance for subsequent plant operations.
PORC directed that no cooldown
be conducted until one SRNI was made operable.
Additionally, containment access was
prohibited and RCS boron sample frequency was increased until at least one SRNI was
available.
Troubleshooting determined that detector failure was the most likely cause of the loss of both
SRNIs.
To restore one channel to operation, an installed spare detector was connected to
SRNI channel N-32.
Post-maintenance
testing was completed satisfactorily and N-32 was
declared operable at 5:30 p.m., March 12, 1993.
Both SRNI detectors were subsequently
replaced and both SRNI channels were restored to service in their normal detector
configuration by March 17, 1993;
Investigation determined the cause of detector failure in both cases to be failure of the center
tungsten electrode.
SRNI detectors are susceptible to this type of failure due to gamma
corrosion of the tungsten electrode.
As long term corrective action, the licensee willbe
replacing the existing SRNI detectors with detectors of a new design that operate at lower
voltage and employ gold-plated tungsten electrodes
(features which reduce gamma corrosion).
Detector replacement criteria willbe established
based on time in service and number of
energizations.
Additionally, predictive measures,
such as detector operating voltage trending
and time domain reflectometry, willbe used in the future to aid in determining the need for
detector replacement.
In summary, the rod control system remained energized for a period of approximately five
minutes without indication of reactor power due to failure of both SRNI channels.
Through
observation of the event, attendance at the subsequent
PORC meeting, discussions with
personnel,
and review of plant operating conditions, the inspector determined that licensee
response
to the event had been appropriate.
Operations department personnel acted in
accordance with in-use and equipment restoration procedures
and promptly stabilized plant
conditions in hot shutdown.
Management responded immediately to evaluate the condition
and provided conservative operating guidance.
Corrective action rapidly restored source
range indication and willbe effective in minimizing the possibility of recurrence.
NRC
notification in accordance with 10 CFR 50.73 was completed within the specified time.
The
inspector had no additional concerns on this matter.
1.4
Control of Operations with Reduced Reactor Coolant System Inventory
t
Steam generator nozzle dams aOow the steam generator primary side to be maintained empty
and available for maintenance
independent of reactor vessel water level.
Installation of these
nozzle dams requires that reactor vessel water level be lowered to approximately the mid-
loop level.
The potential for loss of core cooling capability is significant during such mid-
loop operations due to reduced net positive suction head available to the residual heat
removal (RHR) pumps and unavailability of redundant components due to outage
maintenance.
The inspector assessed
that the licensee's preparations for establishing mid-loop operations
were thorough.
Operating (0) procedure 0-2.3.1, "Draining'nd Operation at Reduced
Inventory of Coolant System," was implemented to ensure redundancy, availability, and
reliability of on- and off-site sources of electrical power and coolant make-up source/paths.
'-2.3.1A,
"Containment Closure Capability in Two Hours During RCS Reduced
Inventory/Operation," was in place to accomplish rapid containment closure ifrequired.
No
operations were conducted during mid-loop operations that would cause unnecessary
perturbations to the RCS.
Independent channels and mechanisms of RCS temperature and
level indication were available.
Multiple sources of water inventory were available and
adequate RCS venting was established prior to blocking the RCS hot legs.
On March 16 and April 8, 1993, the inspector observed operations to establish RCS water
level at mid-loop. In both instances,
the inspector noted that operations department
personnel performed this significant change of plant conditions in a highly professional
manner.
The procedure to establish mid-loop level was accomplished deliberately and was
well controlled.
Operators were knowledgeable of expected indications as well as of
symptoms of potential problems.
No significant deviations from expected system response
occurred and no operational deficiencies were noted.
Quality Assurance personnel
conscientiously monitored the conduct of these mid-loop operations.
Throughout the outage, daily safety assessments
were performed by the outage coordinators
to evaluate the availability of reactivity control systems, core cooling systems, electrical
supplies, containment integrity, and reactor coolant inventory make-up paths during system
configuration changes.
The inspectors found that this graded approach provided an effective
management
and communication tool to assure that plant safety was not compromised,
particularly during mid-loop operations.
2.0
RADIOLOGICALCONTROLS (71707)
2.1
Routine Observations
The inspectors periodically confirmed that radiation work permits were effectively
implemented, dosimetry was correctly worn in controlled areas and dosimeter ieadings were
accurately recorded,
access to high radiation areas was adequately controlled, survey
information was kept current, and postings and labeling were in compliance with regulatory
requirements.
Through observations of ongoing activities and discussions with plant
personnel,
the inspectors concluded that radiological controls were appropriately
implemented.
2.2
Outage ALARAReview
During the 1993 outage, significant improvements were noted in reducing collective radiation
exposure and personnel contaminations from those of past outages.
For the current outage,
the total dosage was 155 person-rem,
compared to 228 person-rem and 296 person-rem for
the 1992 and 1991 outages,
respectively.
Personnel contaminations for this outage numbered
95 cases,
versus 200 cases and 260 cases for the 1992 and 1991 outages, respectively.
The
inspectors determined that these improvements have resulted from aggressive radiological
controls management
that has effectively integrated engineering support to resolving ALARA
issues and has assured
that routine health physics practices were carried out.
Throughout the
outage, the inspectors observed good adherence
to Radiation Work Permits and related
procedures,
detailed pre-job ALARAbriefings, good housekeeping
practices, and prompt
identification of changing radiological conditions with timely implementations of control
measures.
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3.0
MAIN'IENANCE/SURVEILLANCE(62703, 61726)
3.1
Outage Maintenance Sinnmary
Significant maintenance
conducted during the 1993 refueling outage included:
reactor
refueling, including a complete core offload to support service water system and reactor
coolant pump maintenance;
steam generator U-tube inspections and repairs; replacement of
all containment recirculation fan cooler air coolers; "B" reactor coolant pump shaft seal
inspection; reactor coolant pump diffuser inspections; service water system valve
refurbishment; preseparator
drain tank replacement;
and number two low pressure turbine
inspection.
3.2
Service Water System Refurbishment
3.2.1
Failure of Ualve's 4669 and 4738
During the 1993 Refueling/Maintenance
Outage, the licensee implemented phase V of the
Ginna Station Valve and Valve Actuator Improvement Program that began in 1989.
Past
refurbishment/replacement
efforts have been directed at priority valves in the reactor coolant
system (RCS), residual heat removal (RHR) system, safety injection (Si) system, component
cooling water (CCW) system, auxiliary feedwater (~V), and various balance-of-plant
systems.
During the current phase,
service water system (SWS) valves and valve actuators
considered vital to plant safety and reliability were inspected and refurbished or replaced.
Particular attention was directed at inspecting and replacing several 3" and 4" gate valves,
Crane Model No. 101XU, that are no longer manufactured.
An upgraded design, the Crane
Model No. 47 1/2XU, was selected
as the replacement style.
Additional information on the
as-found valve conditions, the licensee's root cause analysis, and resulting SWS
Refurbishment Program scope increase are contained in Inspection Report 50-244/93-08.
During the SWS valve inspections,
several valves were found to be significantly corroded.
Two valves (4669 and 4738) were found to have the valve stems separated
from the valve
discs, with the discs in the flow stream (functionally, fully closed) and the valve stems fully
retracted (and from external observation,
assumed
to be fully locked open).
Valve 4669 in
combination with valve 4760 provides cross connection between the "A" and "B" headers
allowing the Emergency Diesel Generators
(EDGs) to be supplied from either header, in
addition to the normal redundant flow paths.
Valve 4738 is the isolation valve from the "B"
service water header to the safety injection pump thrust bearing coolers, the SI, RHR, and
charging pump mom coolers, and the containment penetration cooler.
Since the spring of 1988, the service water system normal configuration has been cross
connected between the two loops.
This cross connection, in effect, provides for one single
loop where service water pumps from either header can provide all service water loads.
Even with the two affected valves closed, the loops are connected by a normally open 14"
line. Therefore, with this normal lineup, system redundancy was maintained in that any
SWS pump could provide all service water loads even with the valves 4669 and 4738 closed.
Prior to August 1992, during brief periods (typically less than two hours) for monthly service
water pump testing (PT-2.7), the loops were separated.
Redundant cooling to the EDGs was
not affected by this temporary re-alignment.
However, during testing of the "A" loop, valve
4739 (SWS loop "A" isolation valve, that is, the counterpart to valve 4738), was closed.
During these periods, with 4738 unknowingly failed closed, service water would have been
isolated to the room coolers and SI thrust bearing coolers.
Being out of a normal alignment
would only have occurred during performance of surveillance testing and the loops would
have been manually realigned to the normal cross connected configuration, providing
redundant flows, upon the initiation of a significant event during these short periods.
Because of the short duration of the surveillance testing, the low cooling loads (the SI pumps
are not operated, i.e., tested, coincident with the PT-2.7 test) from affected components,
and
the absence'f in-line instrumentation to detect reduced SWS flow to these components,
no
abnormal indications from the isolated loads were readily evident.
This practice of cycling valves 4738 and 4739 during surveillance testing was discontinued in
August 1992.
At that time, the monthly performance of PT-2.7 was replaced with a
quarterly surveillance test, PT-2.7.1, that does not isolate an individual loop to the thrust
bearing coolers and associated
loads.
This change was made to conform with the guidance
contained in Section XI of the 1986 ASME Boiler and Pressure
Vessel (BPV) Code, in that
quarterly inservice testing is an appropriate test frequency.
Ginna Technical Specifications
do not directly address
surveillance testing of SWS components, but refers to the inservice
test requirements
specified in the ASME BPV Code Section XI, and applicable addenda.
Upon identifying the failed valves, site management,
operations personnel,
and site/corporate
engineering staffs developed a comprehensive corrective action plan.
From plant incident
report A-2S.1, No.93-040, Corrective Action Report 2077 was initiated, tasking the
responsible departments within RG&E to evaluate the safety significance, reportability, and
the extent to which the program scope would be increased to verify SWS valve positions and
stem/disc conditions of other Crane 101XU valves.
Additionally, the adequacy of SWS flow
to SI thrust bearing coolers would be evaluated.
The inspectors reviewed selected activities to ascertain whether the SI pump thrust bearing
coolers were receiving unobstructed
SWS flow. During annual outages,
each SI pump is
inspected which includes a thrust bearing and lubrication inspection, in accordance. with M-
11.12.1, "Safety Injection Pump, Mechanical Inspection."
Based on discussions with
mechanical maintenance personnel responsible for performing this activity, the inspectors
determined that never in plant life have thrust bearings been degraded
as a result of
insufficient cooling.
Inspections of bearing lubricating oil in the current outage did not
indicate abnormal cooling.
Additionally, quarterly SI pump surveillance test results did not
identify elevated vibrations, that would be indicative of bearing degradation.
On April 14,
1993, the inspectors observed performance of M-11.12.2, "0'1-A, 1-B, and 1-C Safety
0
Injection Pump Outboard Jacketed Bearing Service Water Cooling System Maintenance."
From observing this activity, the inspectors confirmed that SWS flow was unobstructed
through each of the thrust bearing coolers.
To accurately quantify the flow rate, the site engineering staff attempted to measure SI
bearing cooler flow using an external ultrasonic flow monitor, however, the results were
unreliable.
As a result of these unsuccessful efforts, the licensee has replaced the elbow
connections on the inlet and discharge of each bearing cooler with tee fittings, to permit
installation of pressure or flow instrumentation at some later date.
A procedure to establish
this flow monitoring is under development.
Inspection endings
Through close observation of site management's
response to identifying failed valves 4669
and 4738 in the SWS, the inspector concluded that prompt, comprehensive
actions were
taken to address
the problem and to evaluate the effect that the as-found condition had on
plant safety.
Responsible departments within the RG&E organization were expeditiously
tasked with: evaluating the reportability per 10 CFR 50.72, 50.73, and 10 CFR 21;
assessing
the safety impact of the valves found not in their expected positions; identifying all
Crane 101XU valves in use at the site and confirming that those used in safety-related
applications were intact and in the proper position; and evaluating the preventive maintenance
program scope and schedule for SWS valves.
Through review of safety evaluations
addressing
the impact of the failed valves on plant safety, the inspector concluded that with
the normal single SWS loop configuration and the ability to supply loads from either header,
there was no impact upon the ability to mitigate the effects of an accident with valves 4669
and 4738 closed.
The inspector found that the licensee had the ability to quickly realign the
SWS during the performance of PT-2.1 ifan incident occurred requiring SI pump thrust
bearing cooling, during past SWS monthly testing.
3.2.2
Desludging of Screen House
During this outage period, the licensee inspected underwater components in the screen house.
The screen house is a building containing the traveling screens,
circulating water and service
water pumps, and associated
bays.
The inspection, performed annually in accordance with
M-92, "Underwater Inspection of Mechanical Equipment and Structures in the Screen
House," revealed a buildup of zebra mussels on stationary structures and an excessive
amount of silt deposited.
Walls were subsequently
scraped and the loose material (about 31
tons) was removed from the fore bay, circulating water bay, and service water bay by
vacuuming.
Video inspections recorded the as-found and as-left condition.
Through observing the work in progress,
the inspector concluded that the licensee is taking
prudent actions to assure the continued reliability of the service water system.
3.3
Surveillance Observations
Inspectors 'observed portions of surveillances to verify proper calibration of test
instrumentation,
use of approved procedures,
performance of work by qualified personnel,
conformance to limiting conditions for operation (LCOs), and correct system restoration
following testing.
The following surveillances were observed:
~
Refueling Shutdown Surveillance Procedure (RSSP)-2.2, "Diesel Generator Load and
Safeguard
Sequence Test," revision 44, effective date March 26, 1993, performed
April20, 1993
~
PT-7, "ISI System Leakage Test, Reactor Coolant System," revision 43, effective date
May 7, 1992, performed April22, 1993
The inspector determined through observing this testing that Results and Test personnel
adhered to procedures,
equipment operating parameters
met acceptance
criteria, and
redundant equipment was available for emergency operation.
3.4
Containment Integrated Leak Rate Test
Documents Reviewed
RSSP-6.0,
"Containment Integrated Leakage Rate Test," Revision 19, dated 4/2/93
RSSP-6.1,
"Integrated Leakage Rate Test Valve Alignment," Revision 17, dated
4/7/93
RSSP-6.2,
Pressurization Monitoring of Penetration Free Volumes During CILRT,"
Revision 13, dated 4/2/93
RSSP-6.4,
"Integrated Leak Rate Test Instrument Integrity Check," Revision 3, dated
4/2/93
RSSP-6.5,
"Integrated Leak Rate Test Containment Structural Inspection," Revision
4, dated 3/26/93
RSSP-6.7, "ILRTInstrumentation Preparation," Revision 3, dated 4/5/93
Scope of Review
The inspectors reviewed the Containment Integrated Leakage Rate Test (CILRT) procedures
listed above and supporting procedure change notices for technical adequacy and to determine
compliance with Technical Specification 4.4 and 10 CFR 50, Appendix J.
The inspectors
noted that test procedures
were in general conformance with the guidance of ANSI-ANS
10
56.8-1987, "American National Standard Containment System Leakage Testing
Requirements."
The inspectors discussed
various aspects of the CILRT with licensee
representatives
and contract personnel conducting the test.
The inspectors also reviewed the
test procedure initial conditions and prerequisites,
pressurization equipment setup, monitoring
instrumentation placement, data recording and processing
methods, and test personnel
training.
The licensee utilized 'a contractor, TER Services, Inc., to perform the data
collection and processing.
Results
The inspectors witnessed various phases of the CILRT. Initial alignments were completed
and pressurization
commenced at 2:41 a.m., April 12, 1993.
During the pressure
stabilization phase,
leakage paths were identified in the flange connections to the "C" and
"D" containment recirculation fan cooling system that were installed during this outage.
Subsequently,
containment was depressurized,
blind flanges were installed on the suction.and
discharge piping the "C" and "D" coolers, and the piping hydrostatically tested for leaks.
At
4:55 p.m. on April 13, 1993, containment pressurization
was reinitiated.
Upon stabilizing
test pressure at -35 psig, the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> leakage test period commenced at 2:15 p.m. on April
14, 1993 and ended at 2:15 p.m. on April 15, 1993.
The observed leakage rate was verified
to be less than the 0.75 L, (L, = maximum allowable lmPage rate).
Between 3:30 p.m. and
7:30 p.m. on April 15, 1993, the leakage verification test was conducted.
The results of the
controlled leakage test were satisfactory and the containment was depressurized
in accordance
with the test procedure.
No discrepancies
were identified in the licensee's conduct of the test, review of test
procedures,
or review of results achieved.
In accordance with T.S. 4.4.1.6, RGkE will
submit a technical report for NRC staff review summarizing the conduct of the test and test
results.
3.5
Fire Involving "D" Containment Recirculation Fan Cooler
Overview
On March 19, 1993 at 11:35 a.m., a fire occurred in the roughing filter bank to the "D"
containment recirculation fan cooling system (CRFCS).
The fire resulted when a hot slag
particle from a nearby cutting job made contact with badly loaded roughing filter media,
igniting the filters.
The fire occurred despite the implementation of various fire prevention measures prior to
beginning the job that included a job site area inspection for removal/covering combustible
materials, shielding of the roughing filters with flameproof covers, and posting a fire watch.
11
The fire was promptly reported. by the fire watch to the control room.
Subsequently,
the fire
brigade was dispatched to the scene and quickly extinguished the fire in less than ten
minutes.
Upon extinguishing the fire, a reflash watch was stationed in the area until 5:30
p.m.
No further incidents occurred.
As administrative follow-up to investigate the cause for the fire and identify corrective
actions needed, a plant incident report (A-25.1-93-28) and a Corrective Action Report (CAR-
2076), were developed.
Immediate actions included visually inspecting and meggaring the
"D" CRFCS fan motor to identify possible damaged components,
and inspecting associated
cabling, filter housing and CRFCS structural supports.
Damage was found to be limited to
the "D" CRFCS roughing filters. Since the condition of the "D" bank high efficiency
particulate absolute (HEPA) filters, downstream of the roughing filters, was not readily
apparent,
these filters were scheduled for replacement.
Subsequent
inspection of roughing
filters in unaffected CRFCS units found them to be also badly loaded, with an oily surface
coating of unknown origin.
The roughing filters (sometimes referred to as prefilters, moisture separator pads, or
demisters) are designed to enhance air quality by removing moisture and particulates
entrained in the air stream before it enters the HEPA filters in the CRFCS units. A set of 25
moisture separator pads, in a 5 x 5 array, are located downstream of a single set of inlet
louvers, the CRFCS coiling coils, and a second double set of moisture separating louvers
composing the moisture separator section inside each unit. By design, the HEPA filters
perform their safety-related function even in the presence of entrained water, and as such the
roughing filters do not perform a safety-related function and were not loaded sufficiently, in
this case, to significantly reduce flow.
The inspector reviewed the circumstances
that lead to the roughing filter fire and the
licensee's response.
In performing this review, the inspector evaluated the adequacy of the
licensee's fire protection program by verifying that appropriate preventive measures
were in
place and implemented as required by established procedures.
Through inspection of the "D"
CRFCS roughing filter area, examination of post-fire photographs of the affected area,
review of relevant documentation,
and discussions with license representatives,
the inspector
concluded'hat pre-job fire prevention measures
were implemented as required.
Specificaily,
in accordance with Administrative (A) procedure A-905, "Open Flame, Welding, and
Grinding Permit,
revision 18, Fire Permit No.93-147 was issued prior to beginning the
cutting job to assure that a pre-job area inspection was performed identifying combustible
materials, covering nearby combustibles, and stationing a fire watch with a fire extinguisher
at the job site.
The inspector also concluded that the appropriate contingency measures
as specified in A-
202, "The Fire Protection Program and Ginna Station Staff Responsibilities for Fire
Protection," revision 6, were in place to quickly extinguish the fire. The inspector further
12
concluded that despite the implementation of the various fire prevention measures,
the
licensee was not aware of the flammable condition of the roughing filters. From a review of
licensee procedures,
Maintenance (M)-1306, "Ginna Station Material Condition Inspection
Program," revision 6, no routine inspections were performed of the roughing filter condition.
Additionally, the roughing filters were not routinely visually inspected as part of periodic test
(PT)-47.5, "Containment Fan Recirculation Unit-HEPA Filtration System Efficiency Test,"
revision 3, or other relevant ventilation procedure.
ANSUASME N510-1980, "Testing of
Nuclear AirCleaning Systems," on which PT-47.5 and other relevant ventilation testing
procedures
are based,
recommends
that prefilters be inspected for dirt loading to assure
optimum air flow to the HEPA/charcoal sections of the filtration unit. From a review of
relevant documentation,
the installed media have not been changed or inspected in 5 to 8
years; an exact time period could not be determined.
Based on this review, the inspector concluded that the licensee's failure to periodically assess
the condition of the roughing filters represented
a maintenance program shortcoming.
As
such, this represents
a violation of Appendix B of 10 CFR 50, Criterion XVI, "Corrective
Actions," which states in part... "Measures shall be established
to assure that conditions
adverse to quality, such as failures, ...defective material and equipment, and
nonconformances
are promptly identified and corrected."
(50-244/93-06-01)
As immediate corrective action, the licensee replaced the roughing filters in all CRFCS units.
Additionally, samples of the loaded media were removed for analysis by an independent
laboratory to determine the chemical nature of the contaminants and assess
the effect that
combustion products may have on electrical equipment.
3.6
Containment Material Condition
The inspectors conducted several routine safety inspections in the containment building. The
inspectors
assessed
that material conditions within the containment building were generally
good.
A number of minor material discrepancies
were noted and passed on to the licensee
for corrective action.
Although none of these items were safety significant, the inspector
considered that existing licensee inspection and self-monitoring programs,
such as system
walkdowns, zone inspections,
safety inspections, and supervisory tours, could be more
effective in self-identification of such deficiencies.
The inspector considered
that licensee
corrective actions for identified deficiencies were appropriate and concluded that material
conditions in containment were adequate for the resumption of critical operations.
4:0
SECURI'IY (71707)
4.1
Routine Observations
During this inspection period, the resident inspectors verified that x-ray machines and metal
and explosive detectors were operable, protected area and vital area barriers were well
maintained, personnel'were properly badged for unescorted or escorted
access,
and
compensatory
measures
were implemented when necessary.
No unacceptable
conditions
were identified.
13
4.2
Storm Damage to Site Perimeter
Fence-'he
blizzard that occurred on March 13-14, 1993, caused damage to portions of the site
perimeter fence.
High winds, sub-freezing temperatures,
and water spray from Lake Ontario
formed ice on the fences along the lake front to such an extent that they buckled under the
prevailing forces.
Approximately 300 feet of the outer fence and 100 feet of the inner fence
were so damaged.
Associated damage to the intrusion detection system affected much of the
remainder of the site perimeter.
The licensee responded by implementing full compensatory
measures for affected portions of the site perimeter.
Repairs to the intrusion detection
system and perimeter fence were completed.
The inspector determined that compensatory
measures
established for loss of the intrusion
detection system and degradation of the perimeter fence were adequate and timely. Repair of
storm damage was promptly completed.
The inspector had no additional concerns on this
matter.
5.0
EMERGENCY PREPAID)NESS (71707)
5.1
Siren Test
On April 6, 1993, the licensee's Emergency Preparedness
staff conducted the annual siren
activation test.
The test requires that all of the sirens be actuated and run uninterrupted for a
three minute period.
Results of this test were that three of 96 sirens failed to perform
properly.
With 97 percent of the sirens fully operating, the licensee met the FEMA
acceptance
guidelines of greater than 90 percent operable.
The three failed sirens were
promptly repaired.
From a review of the test results, and through discussions with licensee representatives,
the
inspectors determined that, in addition to successfully performing the annual siren activation
test, quarterly growl tests and monthly silent tests have been performed as specified by
NUREG-0654, "Criteria for Preparation and Evaluation of Radiological Emergency Response
Plans and Preparedness
in Support of Nuclear Power, Plants."
6.0
ENGINFXMNG/TECHNICALSUPPORT (71707, 92701)
6.1
Mssing Reactor Coohnt hnp Diffnser Bolt
During the 1990 refueling outage, part of a bolt was discovered inside of the reactor vessel,
on top of the lower core plate.
Through examiiiation of the bolt, the licensee determined that
it was the type used to secure the reactor coolant pump diffuser adapters.
Although the
source of the bolt could not be established without examining the RCP diffuser adaptors,
the
licensee pursued the worst-case assumption that it had backed out of one of the RCPs (as
opposed to being a spare that had inadvertently been left in the RCS following RCP
maintenance in an earlier outage).
Since any examination of RCP internals would require
'
14
extensive preparation,
the licensee demonstrated,
through analysis, that continued operation
with such a condition could be justified; in parallel, planning was initiated to conduct a'direct
inspection of the RCP diffuser adaptors.
Actions were coordinated and tracked under
corrective action report (CAR) 2001, "Foreign Material Found in the Reactor Vessel."
Analysis conducted by the pump vendor demonstrated
that an RCP would operate
satisfactorily under all conditions with one of the 16 diffuser adaptor bolts missing.
RG&E
technical engineering evaluated the risks associated
with continued plant operation with the
remaining portion of the bolt in question not accounted for, and determined that this did not
create an unreviewed safety question.
Running RCPs exhibited normal operating
characteristics.
Based on these findings, the licensee determined that continued plant
operation prior to RCP inspection was acceptable.
The licensee determined that the RCP diffuser adaptor inspections should be conducted by
remote video camera.
To facilitate access,
the inspection would be done following a
complete reactor core offload. In that a core offload would be required to support service
water system maintenance during the 1993 refueling outage, and contingent on continued
normal operation of the RCPs, the video inspection was scheduled for 1993.
In preparation for the RCP inspection, a full size mock-up of the applicable RCS piping was
constructed to test the inspection equipment.
The equipment consisted of a video camera
mounted on a fiber glass push rod; insertion into the RCS was made through a snorkel
adaptor at the steam generator cold leg manway.
Operator training was conducted using this
mock-up prior to the actual inspection.
No significant procedural or equipment deficiencies
were identified as a result of the mock-up training.
The RCP diffuser adaptor inspections commenced
on March 22, 1993, in accordance with
EM-774, "Remote Visual Examination of Reactor Coolant Pump Diffuser Adaptor Ring and
Bolting," revision 0, effective date March 5, 1993., All 16 bolts were found to be in place
on the "B" RCP, and one was found to be missing from the "A" RCP. Allremaining
installed diffuser adaptor bolts were determined to be fully inserted.
No other material
deficiencies were noted and the inspection activities concluded on March 24, 1993.
The inspector reviewed completed work order 9320011, "Perform Remote Video Inspection,
"A"and "B" Reactor Coolant Pumps," and noted no discrelencies.
The inspector concluded
that the activities to inspect the RCP diffuser adaptors had been well planned and successfully
implemented.
CAR 2001 was an effective tool in progressing a three-year old deficiency
through development and implementation of corrective action.
Final corrective action to
replace the missing bolt willbe accomplished when the "A" RCP requires future
maintenance.
The inspector had no additional concerns on this matter.
'CI
15
6.2
Containment Recirculation Fan Cooler Replacements
The reactor containment building contains four recirculation fan cooler units.
The safety
function of these units is to condense
steam released during either a loss of coolant or steam
line break accident, and thereby limitthe time that the containment building is subject to high
internal pressure.
Each unit contains three primary heat exchangers
that are supplied by the
service water system.
Containment recirculation fan cooler heat exchangers
had been scheduled for replacement in
1995; however, in light of the increasing number of service water leaks, the licensee
accelerated
this schedule,
to replace these heat exchangers
during the 1993 refueling outage.
The replacement primary heat exchangers
are of an advanced design, with greater
erosion/corrosion
resistance
and a physical configuration which willprovide both better
access for maintenance
and greater fiexibilityin selecting repair techniques.
The inspector observed portions of production work to install the containment recirculation
fan cooler heat exchangers.
The licensee utilized four 10-hour crew shifts to provide around-
the-clock support for this maintenance effort.
Continuous engineering support was also
available, with two licensee field engineers,
the licensee liaison engineer,
and one contractor
engineer covering the work. Through discussions with personnel, observation of work in-
progress,
and completion of an aggressive
schedule,
the inspector concluded that good
engineering support was provided for the containment recirculation fan cooler heat exchanger
replacement.
The inspector reviewed station modification procedures SM-5275.1 and .2, "Units "A" and
"B" ("C" and "D") Containment Recirculation Fan Cooler Replacements."
These procedures
served as the coordinating documents for accomplishment of production work, inspection,
testing, and acceptance of the recirculation fan cooler modifications.
No deficiencies were
noted.
Modification testing was completed at the close of the inspection period, but the
results were still under licensee review.
The inspector had no further questions at this time.
6.3
Safety IILiection System Accumulator Drain Vabes Seismic Qualification
During a routine safety inspection in containment, the inspector noted that the safety injection
system accumulator drain valves, AOV-844A and B, did not appear to be properly
supported.
Specifically, the valves each appeared to be missing a support bracket between
the air operator and the base of the SI accumulator.
The inspector had observed that
similarly sized air operated valves in containment had such supports, and a ground-off area
on the base of each of the SI accumulators
suggested
that such brackets had, at one time,
been installed.
The inspector noted that the AOV-844A and B air operators could be set into
cyclic, side-to-side motion about the axis of the drain line, with only slight exertion.
The
inspector questioned the seismic qualification of these valves.
'
16
The licensee reported 'that- diagonal braces had, in fact, been installed on valves AOV-844A
and B in the past, but that they had been removed about 10 years ago as a result of analyses
conducted during the seismic upgrade program.
The inspector 'was in the process of
reviewing the applicable piping stress analysis reports at the close of the inspection period.
The inspector had no further questions at this time.
7.0
SAFETY ASSESSMFAT/QUALITYVXRIHCATION(9071?, 90713, 92701,
40500)
7.1
Periodic Reports
Periodic reports submitted by the licensee pursuant to Technical Specification 6.9.1 were
reviewed.
Inspectors verifie that the reports contained information required by the NRC,
that test results and/or supporting information were consistent with design predictions and
performance specifications,
and that reported information was accurate.
The following
reports were reviewed:
No
Licensee Event Reports
Monthly Operating Reports for February and March 1993
unacceptable
conditions were identified.
A licensee event report (LER) submitted to the NRC was reviewed to determine whether
details were clearly reported, causes were properly identified, and corrective actions were
appropriate.
The inspectors also assessed
whether potential safety consequences
were
properly evaluated, generic implications were indicated, events warranted onsite follow-up,
and applicable requirements of 10 CFR 50.72 were met.
The following LER was reviewed (Note: date indicated is event date):
~
93-001, Loss of Source Range Detector Indication During Energization Due To Faulty
Detectors
The inspector concluded that the LER was accurate and met regulatory requirements.
No
unacceptable conditions were identified.
8.0
ADMINISTRATIVE(71707, 30702, 94600)
8.1
Backshift and Deep Backshift Inspection
During this inspection period, backshift inspections were conducted on the following dates:
March 16 and April 8, 1993.
Deep backshift inspections were conducted on the following
dates:
March 13, 20, 21, 27, April 3 and 22, 1993.
17
8.2
Exit Meetings
At periodic intervals and at the conclusion of the inspection, meetings were held with senior
station management to discuss the scope and findings of inspections.
The exit meeting for
inspection report 50-244/9342 (inservice inspection program, conducted March 23-26, 1993)
was held by Mr. Pralmh Patnaik on March 26, 1993.
The exit meeting for inspection report
50-244/93-07 (health physics, conducted April 12-16, 1993) was held by Mr. James Noggle
on April 16, 1993.
The exit meeting for inspection report 50-244/93-08 (service water
system outage maintenance,
conducted April 12-16, 1993) was held by Mr. Harold Gregg on
April 16, )993.
The exit meeting for inspection report 50-244/9346 was held on April22,
1993.