ML18010B089
| ML18010B089 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 05/05/1993 |
| From: | Christensen H, Darrell Roberts, Tedrow J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML18010B086 | List: |
| References | |
| 50-400-93-08, 50-400-93-8, NUDOCS 9305180240 | |
| Download: ML18010B089 (27) | |
See also: IR 05000400/1993008
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UNITED STATES
NUCLEAR REGULATORY COMMISSION
REGION II
101 MARIETTASTREET, N.W.
ATLANTA,GEORGIA 30323
Report No.:
50-400/93-08
Licensee:
Carolina
Power and Light Company
P. 0.
Box 1551
Raleigh,
NC 27602
Docket No.:
50-400
/
Facility Name:
Harris
1
Inspection
Conducted:
March 20 - April 16,
1993
Inspectors:
J.
edrow
en or Resident
Inspectop
D.
obert
,
ident Inspector
Approved by:
H. I.hristensen,
Section Chief
Division of Reactor Projects
SUMMARY
Licensee
No.:
ssH
Da e
igned
Date Signed
Dat
igned
Scope:
This routine inspection
was conducted
by the resident
inspectors
in the areas
of plant operations,
radiological controls, security, surveillance
observation,
maintenance
observation,
design
changes
and modifications, fire
protection/prevention,
essential
services chilled water system reliability,
licensee
event reports,
and licensee
action
on previous inspection
items.
Numerous facility tours were conducted
and facility operations
observed.
Some
of these tours
and observations
were conducted
on backshifts.
Results:
One violation and
one deviation were identified:
Failure to properly
implement inservice testing for components with data in the alert range,
paragraph 2.c.(l); Performance of non-emergency
safety-related
maintenance
without appropriate
preplanning,
paragraph
4.a.
A licensee identified non-cited violation was identified regarding the failure
to maintain apropriate actuation setpoints
for the containment
vacuum relief
system,
paragraph 2.c.(2).
Maintenance activities to identify and correct deficiencies with air handler
AH-92A were considered
to be poor.,
paragraph
4.b.
Engineering
support
and contingency planning for a potentially inoperable
emergency battery cell were considered
to be weak,
paragraph
4.d.
9305180240
930506
ADDCK 05000400
8
REPORT
DETAILS,
1.
Persons
Contacted
Licensee
Employees
- J. Cribb, Manager,
equality Control
- C. Gibson,
Manager,
Programs
and Procedures
- H. Hamby,
Manager,
Regulatory
Compliance
- D. McCarthy, Manager,
Regulatory Affairs
- T. Morton, Manager,
Maintenance
- J. Nevill, Manager,
Technical
Support
- W. Robinson,
General
Manager,
Harris Plant
- W. Seyler,
Manager,
Outages
and Modifications
H. Smith, Hanager,
Radwaste
Operation
- D. Tibbitts, Manager,
Operations
- G. Vaughn, Vice President,
Harris Nuclear Project
- W. Wilson, Manager,
Spent Nuclear Fuel
- L. Woods,
Manager,
Systems
Engineering
Other licensee
employees
contacted
included office, operations,
engineering,
maintenance,
chemistry/radiation
and corporate
personnel.
- Attended exit interview
2.
and initialisms used throughout this'report
are listed in the
last paragraph.
Review of Plant Operations
(71707)
The plant continued in power operation
(Mode 1) for the duration of this
inspection period.
a.
Shift Logs
and Facility Records
The inspector
reviewed records
and discussed
various entries with
operations
personnel
to= verify compliance with the Technical
Specifications
(TS)
and the licensee's
administrative procedures.
The following records
were reviewed:
shift supervisor's
log;
control operator's
log; night order book; equipment
record; active clearance
log; grounding device log; temporary
modification .log; chemistry daily reports; shift.turnover
checklist;
and selected
radwaste
logs.
In addition, the inspector
independently verified clearance
order tagouts.
The inspectors
found the logs to be readable,
well organized,
and
provided sufficient information on plant status
and events.
Clearance
tagouts
were found to be properly implemented.
No
violations or deviations
were identified.
Facility Tours
and Observations
Throughout the inspection period, facility tours were conducted to
observe operations,
surveillance,
and maintenance activities in
progress.
Some of these
observations
were conducted during
backshifts.
Also, during this inspection period, licensee
meetings
were attended
by the inspectors
to observe
planning
and
management activities.
The facility tours
and observations
encompassed
the following areas:
security perimeter fence;
control
room; emergency diesel
generator building; reactor
auxiliary building; waste processing
building; turbine building;
fuel handling building; emergency
service water building; battery
rooms; electrical
switchgear
rooms;
and the technical
support
center.
During these tours,
the following observations
were made:
Monitoring Instrumentation
- Equipment operating status,
area
atmospheric
and liquid radiation monitors, electrical
system lineup, reactor operating
parameters,
and auxiliary
equipment operating
parameters
were observed
to verify that
indicated parameters
were in accordance
with the
TS for the
current operational
mode.
(2)
Shift Staffing - The inspectors verified that operating
shift staffing was in accordance
with TS requirements
and
that control
room operations
were being conducted
in an
orderly and professional
manner.
In addition,
the inspector
observed shift turnovers
on various occasions
to verify the
continuity of plant status,
operational
problems,
and other
pertinent plant information during these turnovers.
(3)
Plant Housekeeping
Conditions
- Storage of material
and
components,
and cleanliness
conditions of various areas
throughout the facility were observed to determine whether
safety and/or fire hazards
existed.
(4)
Radiological
Protection
Program - Radiation protection
control activities were observed routinely to verify that
these activities were in conformance with the facility
policies
and procedures,
and in compliance with regulatory
requirements.
The inspectors
also reviewed selected
radiation work permits to verify that controls were
adequate.
Security Control - The performance of various shifts of the
security force was observed
in the conduct of daily
activities which included:
protected
and vital area
access
controls;
searching of personnel,
packages,
and vehicles;
badge
issuance
and retrieval; escorting of visitors;
patrols;
and compensatory
posts.
In addition, the inspector
observed
the operational
status of closed circuit television
monitors, the intrusion detection
system in the central
and
secondary
alarm stations,
protected
area lighting, protected
and vital area barrier integrity,
and the security
organization interface with operations
and maintenance.
The inspectors
found plant housekeeping
and material condition of
components
to be satisfactory.
The licensee's
adherence
to
radiological controls, security controls, fire protection
requirements,
and
TS requirements
in these
areas
was satisfactory.
Review of Nonconforman'ce
Reports
Adverse 'Condition Reports
were reviewed to verify the following:
TS were complied with, corrective actions
and generic
items were
identified and items were reported
as required
by 10 CFR 50.73.
(1)
ACR 93-126 reported that the "A" spent fuel pool cooling
pump (FPC-lA) entered
the high alert range for differential
pressure
during
a quarterly surveillance test
on June
23,
1992,
but the
pump
had not been placed
on
an increased
testing frequency
(ITF) or analyzed
as required
by Inservice
Inspection
Program
Procedure
ISI-203,
ASME Section
XI Pump
and Valve Program Plan.
The licensee
discovered this error
while reviewing the data for a March 12,
1993 quarterly
test.
Following the licensee's
discovery,
the
pump was
immediately placed
on an ITF and the licensee
reviewed other
pump data to determine if any more
pumps
had
been missed.
During discussions
with the
NRC inspector,
the licensee
indicated that this review yielded
no additional
examples of
oversight
and that the above instance
appeared
to be
an
isolated
case.
When the inspector reviewed historical data
for all of the
pumps in the
IST program,
12 instances
of
missed
ITFs or the failure to perform an analysis for pumps
that had gone into either the high or low alert ranges for
flow, differential pressure,
or vibration over the last four
years
were found.
Examples
included high alert differential
presure
data for the "A" containment
spray
pump in February
1990
and again
on FPC-lA in December
1991.
The "B" service
water booster
pump went into low flow alert
on three
separate
occasions
(August 1991,
March 1992,
and September
1992) prior to being placed
on ITF in September
1992.
The
TDAFW pump went into high alert for vibration on six
occasions
between
1989
and
1992 without any required
corrective actions.
When the inspector reviewed the files
for these
pumps with the licensee, it was found that no
records of corrective actions existed for the unacceptable
test data identified by the inspector.
,The inspector
considered that
a lack of a proceduralized
review process
for IST data,
which could potentially fall into the alert
range,
contributed to this problem.
Currently, the
Section
XI required action range,
which defines
pump
operability, is referenced
as acceptance
criteria in
Operations
Surveillance
Test procedures.
This provides
a
formal means of identifying data which falls in the required
action range.
The inspector verified that none of the
required actions
were missed
and that
pump operability was
not affected
by the missed
ITFs.
The inspector also
verified that the
pumps are currently being tested
on
a
frequency
commensurate
with recent test data.
The test results for the spent fuel pool cooling
pump
identified by the licensee
and the twelve examples
found by
the inspector
were all considered
to be in violation of the
licensee's
inservice testing procedure.
Although the
licensee identified the first example, this violation is
being cited due to the excessive
number of examples later
identified by the
NRC inspector during his followup review.
Violation (400/93-08-01):
Failure to properly implement
inservice testing for components
with data in the alert
range.
In addition to the above issue,
the inspector identified
several
borderline
cases
where surveillance test data fell
right on the margin for the acceptable
and alert ranges.
For pumps,
Section
XI of the
ASHE Code defines the
acceptable
range for flow to be 0.94 to 1.02 of the
established
baseline
flow.
However, Section
XI also defines
the low and high alert ranges
as 0.90 to 0.94
and 1.02 to
1.03 of the baseline
flow respectively.'ence,
the alert
range
boundaries
overlap with the acceptable
ranges
at its
margins
and allows data which falls on the border to be
interpreted either way.
This same ambiguity exists for
vibration (0 to
1 mil acceptable
and
1 to 1.5 mil high
alert)
and the other monitored parameters.
The inspector
found flow data for three successive
tests
(September
1992,
December
1992,
and February
1993) performed
on the "A"
service water booster
pump
and
one
(Harch
1992) for the "A"
RHR pump that were
on the acceptable
and alert range
margins.
Several
instances
were found for the
TDAFW pump
and others
where vibration data
was exactly
1 mil.
Since
Section
XI was
ambiguous
in this regard,
the licensee
had
interpreted this borderline data to be acceptable
and
consequently
did not place the
pumps
on ITF or perform any
analysis
on the data.
Although
a number of items in
subsection
IWP are subject to interpretation
and have
documented
interpretations
in the licensee's
implementation
procedure
ISI-203,
no such formal interpretation existed for
the analysis of data which falls on the margins of the alert
ranges.
The inspector discussed this matter with the
licensee
who agreed that there should
be
a procedural
interpretation for qualifying borderline test data.
ACR 93-142 reported that the containment
vacuum relief
system actuation setpoint
was not within the limits
established
by the TS.
requires
the containment
vacuum relief system
be operable
with an actuation setpoint of equal to or less negative
than
-2.5
INWG differential,pressure
(containment
pressure
less
atmospheric
pressure).
During a review of maintenance
procedures
for a plant modification, licensee
personnel
discovered that the differential pressure
transmitters,
'used
to actuate
the system,
sense
a differential pressure
between
the containment building and the Reactor Auxiliary Building
(RAB).
This instrumentation
has
been maintained
by the
licensee
by the performance. of loop calibration procedures
for the transmitters with a setpoint of -2.5
INWG with a
tolerance of 0.25
INWG.
Since the
RAB pressure
is
maintained
at
a negative pressure relative to outside
atmosphere
so
as to monitor and filter potential
airborne
radioactive release
pathways,
the effective actuation
setpoint for the vacuum relief system includes the actuation
setpoint plus the negative pressure
at which the
RAB is
maintained
(-0.2 - -0.4
INWG).
This condition exceeded
the
TS required actuation setpoint.
When informed of this situation
on Parch
31,
1993,
operations
personnel
secured
the
RAB normal ventilation to
equalize the
RAB pressure
with atmospheric
pressure.
This
was
a conservative
action until plant engineering
could make
a determination of system operability.
On April 1,
1993,
an
engineering
evaluation
concluded that system operability was
not affected
and that the current configuration was in
accordance
with plant design.
The
RAB normal ventilation
was subsequently
returned to service.
On April 2,
1993, the
RAB normal ventilation was again
secured
due to concerns
regarding'compliance
with the exact wording of the TS.
The
containment
vacuum relief valve actuation setpoint
was
subsequently
revised via a temporary modification (PCR-6852)
to establish
a value of -1.0
INWG which allowed
a margin for
RAB pressure- control.
The inspectors
researched
the
FSAR and licensee calculations
which supported
operation of the system.
Section 6.2. 1
.1.3.4 of the
FSAR supported
the present
design of the
containment
vacuum relief system.
Calculation 012, dated
May 2,
1986,
assumed
an initial containment
vacuum of -4.0
INWG before actuation of the vacuum relief system.
The
results of this calculation concluded that the maximum
differential pressure
between
containment
and the
atmosphere
would be less
than the design value of 2.0 psi
as
specified in the
FSAR.
Since the negative
pressure
maintained
in the
RAB in conjunction with the actuation
setpoint of -2.5
INWG would not have exceeded
the maximum of
-4.0
INWG assumed
in the calculation,
the inspector
concluded that no safety concern existed
and that the
current plant design
was in accordance
with the
FSAR.
However, the licensee
was encouraged
to correct the wording
of the
TS to reflect the actual plant design configuration
which 'measures differential pressure
between
the containment
building and the
RAB.
This violation will not be subject to
enforcement
action because
the licensee's
efforts in
identifying and correcting the violation meet the criteria
specified in Section VII.B of the Enforcement Policy.
NCV (400/93-08-02):
Failure to maintain appropriate
actuation setpoints for the containment
vacuum relief
system.
Surveillance Observation
(61726)
Surveillance tests
were observed to verify that approved
procedures
were
being used; qualified personnel
were conducting the tests;
tests
were
adequate
to verify equipment operability; calibrated
equipment
was
utilized;
and
TS requirements
were followed.
The following tests
were
observed
and/or data reviewed:
~ OST-1013
1A-SA Emergency Diesel Generator Operability Test Monthly
Interval
~ OST-1023
Offsite Power Availability Verification Weekly Interval
~ OST-1026
Leakage
Evaluation Daily Interval
~ OST-1085
1A-SA Diesel
Generator Operability Test Semi-annually
~ EPT-033
Emergency
Safeguards
Sequencer
System Test
~ EPT-194T
Emergency Diesel
Generator
lA-SA Governor Adjustment
and
Response
Testing
The performance of these
procedures
was found to be satisfactory with
proper use of calibrated test equipment,
necessary
communications
established,
notification/authorization of control
room personnel,
and
knowledgeable
personnel
having performed the tasks.
No violations or
deviations
were observed.
a ~,
During the initial performance of procedure
OST-1085 at 9:07 p.m.
on March 20, the "A" emergency diesel
generator failed to
establish
a stable output frequency within the time limit of 10
seconds.
Plant operators
using
a hand held stop watch measured
a
time of 10.03 seconds for this parameter to stabilize.
The diesel
was subsequently
declared
A recorder device
was
installed to measure
the time for the diesel
generator to achieve
rated voltage
and frequency.
The diesel
was started
per
an
operating
procedure for a second
time at approximately 4:30 a.m.
on March 21 with satisfactory
frequency stabilization time.
At
b.
5:08 a.m.
on Harch 21, the diesel
was started
a third time in
accordance
with procedure
OST-1085 during which an acceptable
frequency stabilization time of 9.36 seconds
was obtained.
During
the two later starts,
the time was measured
with hand held stop
watches
and the recorder device.
These starts
showed that, in
some cases,
the times measured
by stop watch were longer than
those
measured
by the recorder
devices
by as
much
as
one second.
The licensee
concluded that
a time measuring
mistake
had
been
made
on the first start attempt
and declared
the diesel
As mentioned in NRC Inspection
Report 50-400/93-07,
several
previous diesel start times have
exceeded
the
10 second limit.
Licensee
personnel
discovered that most of the slow starts
occurred during the performance of surveillance tests
where safety
injection slave relays
were actuated
to produce the diesel start
signal
as
was the case with procedure
OST-1085.
The licensee
believes
the diesel starting time is being measured
inconsistently
during these tests
when the slave relays
are actuated.
Further investigation for the slow diesel
generator start time was
performed
by the licensee
between
Harch
24 and Harch 26.
The fuel
control shafts
and
pump racks were inspected
by the equipment
vendor representative..
No problems
were identified.
Procedure
EPT-194T was then performed
on Harch
26 to adjust the diesel
governor response.
After adjustments
were
made to the governor,
procedure
OST-1013
was performed during which
a substantially
improved frequency stabilization time of 8.6 seconds
was achieved.
During a review of the
TS associated
with surveillance
procedure
OST-1023,
the inspector noticed that
TS 4.8. 1. l.l.a required that
the connecting circuit for the offsite transmission
network and
the onsite safety-related distribution system
be verified operable
by checking correct breaker
alignment
and power availability.
Although the procedure
adequately
checked circuit breaker
positions, it did not contain
a requirement to verify that
switchyard voltage
was present.
Although power availability is
usually obvious, certain outage conditions could make the power
availability check important.
The inspector
recommended
that the
surveillance
procedure
be enhanced
to include this check.
Haintenance
Observation
(62703)
The inspector observed/reviewed
maintenance activities to verify that
correct equipment clearances
were 'in effect; work requests
and fire
prevention work permits were issued
and
TS requirements
were being
followed.
Haintenance
was observed
and work packages
were reviewed for
the following maintenance activities:
~ Troubleshooting/replacement
of fan bearings for air handler AH-92A.
~ Replacement of AH-92A supply breaker in accordance
with procedure
CH-
E0010,
480 Vac Holded Case Circuit Breaker Test.
~ Troubleshoot
cause for axial flux difference channel drifting in
accordance
with procedure
HST-I0045, Calibration of Nuclear
Instrumentation
System
Power
Range
N42.
~ Inspection of "A" emergency diesel
generator fuel control shafts
and
pump racks.
~ Troubleshoot/repair
the
TDAFW pump which tripped on mechanical
during surveillance testing.
~ Rebuild "B" CSIP using
new rotating assembly
and mechanical
seals
in
accordance
with procedures
CH-H0019, Pacific Charging/Safety
Injection
Pump Size
2 1/2"
RL Type IJ Disassembly
and Maintenance,
High-Speed
Gear Drives Type SU-19 for Charging/Safety
Injection
Pump,
Disassembly
and Maintenance,
and HPT-H0059,
Charging/Safety
Injection
Pump Nonmetallic Component
Replacement
-and
Lubrication (Mechanical
Environment gualification).
~ Calibrate pressure differential switch for containment
vacuum relief
system in accordance
with temporary modification PCR-6852.
~ Charge Cell 828 on
1B-SB emergency battery per procedure
Station Battery Single Cell Charging,
and retest in accordance
with
procedure
HST-E0011,
lE Battery quarterly Test.
The performance of work was satisfactory with proper documentation of
removed
components
and independent verification of the reinstallation.
'a ~
The inspector requested
a listing of all priority work performed
in the previous thirty days.
This printout contained
19 work
tickets.
A review of work ticket approval
times
compared to
timekeeping data revealed that one priority 3 job which regarded
the repair of the "A" emergency diesel
generator
control panel
was
started
before preplanning
was performed.
The licensee's
procedure for controlling maintenance,
HHH-012,
Maintenance
Work Control Procedure,
contains provisions for the
conduct of priority/emergency maintenance
and allows the shift
foreman to authorize the performance of maintenance activities
without prior preplanning,
reviews,
and without a planned work
ticket in emergency situations
where immediate actions
are
required to protect the health
and safety of the public, protect
equipment
or personnel,
and prevent the deterioration of plant
conditions to potential
unsafe levels.
This procedure listed
priority level
1,
2 and
3 as potential activities which allow
maintenance initiation without the prior preplanning.
The
licensee
defines priority 2 and
3 maintenance
as that required to
correct
a condition which is in violation of regulatory require-
ments
and to correct
a condition which requires
an imminent plant
shutdown.
The inspector
reviewed Regulatory
Guide 1.33, guality Assurance
Program Requirements
(Operation),
section
1.8 of the
FSAR,
and
discussed
the intent of the work control procedure with licensee
management.
Section
9 of Regulatory
Guide 1.33,
Procedures
for
Performing Haintenance,
states that maintenance
that can affect
the performance of safety-related
equipment
should
be properly
preplanned
and performed in accordance
with written procedures.
Section
1.8 of the
FSAR describes
the extent to which the licensee
complies with Regulatory
Guide 1.33
and states that maintenance
shall
be preplanned
and performed in accordance
with written
procedures
except in emergency or abnormal
operating conditions
where
immediate actions
are required to protect the health
and
safety of the public, to protect equipment or personnel,
or to
prevent the deterioration of plant conditions to unsafe levels.
Although the inspector
agreed that certain situations
which
involve a danger to the health
and safety of the public, or to
protect plant personnel
and equipment,
must
be expeditiously
corrected,
the inspector considered
the omission of preplanning to
avoid imminent plant shutdowns to be
a deviation of the written
commitment in the
FSAR.
Deviation (400/93-08-03):
Performance of non-emergency
safety-
related
maintenance
without preplanning.
b.
Several
problems were experienced
with air handler AH-92A.
This
fan supplies cooling air to
a safety-related
motor control center.
On Harch
20 licensee
personnel
noticed that the fan was making
an
unusual
noise
and that the shaft
was moving excessively.
Haintenance
was performed which replaced
the outboard
fan bearing.
The cause for the
bad bearing
was determined to be
a loose nut on
the bearing locking collar.
On Harch 30 the fan again
had to be
worked because
the outboard fan bearing
had seized.
The fan shaft
was repaired
and both fan bearings
were replaced to corr'ect the
damage.
The cause for this condition was determined to be
overtight drive belts.
On April
1 excessive
vibration was noticed
on the fan motor.
Troubleshooting
uncovered that the motor sheave
was loose
and
a key which was supposed
to secure this component
in
place
was found on the bottom of the air handler unit.
The
licensee
determined that the key had
been
absent for some time and
. .this contributed to the motor vibration.
The key and
a new sheave
was installed.
The licensee is presently performing
an
investigation into the root cause for the problems
associated
with
this fan.
The inspector considered
the maintenance activities to
identify and correct the problems with AH-92A to be poor
as they
resulted
in excessive
equipment out of service times to repair.
.f
10
On March
18 licensee
personnel
discovered
an outboard
seal
leak of
approximately
one
gpm on the "B" CSIP.
Minutes earlier, control
room personnel
had received
low seal injection flow alarms to the
"A" and
"B" reactor coolant
pumps
as well as indications that the
charging
pump motor was running
on higher than normal current,
and
that
pump discharge
pressure
had decreased
to approximately
2500
psig from 2700 psig.
Control
room personnel
immediately secured
the
pump
and declared it inoperable.
During the
pump disassembly
and maintenance activities, licensee
personnel
unsuccessfully
attempted to remove the balancing
drum retaining nut which mates
with the
pump shaft
between the discharge
impeller and the
mechanical
seal
package.
The nut was jammed, indicating that the
pump shaft
had broken beneath it.
The balancing
drum, which
prevents
axial
pump thrust
and protects the outboard mechanical
seal
package,
had indications of wear.
The seal faces'ad
a wear
pattern which indicated that they had
seen
excessive
pressures
because
the balancing
drum had failed.
Following unsuccessful
attempts to fully disassemble
the old rotating element,
the
licensee
replaced
the entire element
and mechanical
seal
assembly
with spares.
Following installation of the
new pump
and seals,
the
licensee
broke the drum retaining nut on the old assembly for
further investigation.
It was verified that the shaft had,indeed
been
severed
below the retaining nut and that this initiated the
pump failure.
According to licensee
personnel,
several
shaft
failures
have
been reported
by the industry for this type of
charging/safety
injection pump.
All three of the CSIPs
are
11-
stage centrifugal
pumps that were manufactured
and tested
by
Pacific
Pumps.
The inspector reviewed the
pump vendor's technical
manual
and the
licensee's
work packages
to verify that the
pump rebuild had
been
performed in accordance
with vendor
recommendations.
Although the
vendor manual specifies
performing
a full flow test prior to
returning the
pump to operable
status,
the licensee
has opted to
test the
pump on reduced flow due to current plant operating
conditions.
The licensee will develop
a special
procedure to
accomplish this post-maintenance
testing.
In the meantime,
the
performance of the "A" CSIP, which has
an operating life similar
to the old "B" CSIP,
and
had
a much lower level vibration, will be
monitored closely.
Licensee
management
has decided
not to replace
the rotating element
on the "A" CSIP until signs of impending
failure is seen or occurs.
Inspector
Follow-up Item (400/93-08-04):
Follow the licensee's
activities to retest
the "B" CSIP, determine
the root cause of its
failure,
and assess
any generic implications.
On March 16, during performance of procedure
1E Battery
quarterly Test,
the individual cell voltage reading
on
battery cell
828 fell below the 2. 13 Vdc limit. The licensee
began
a 24-hour continuous individual cell charge
on March
18 to bring
the cell voltage
back above the Category
B requ'irement.
Technical
11
Specification 4.8.2. 1 states
that the
1E emergency batteries
may
be considered
operable for any Category
B parameter
outside the
"limits" shown
on Table 4.8-2
as long as the parameters
are within
their "allowable values"
and restored to within limits within 7
days.
On Friday, Harch 19, three
days after the adverse
condition
was identified, licensee
personnel
began
addressing
the
possibility that, following the continuous
recharge
which was
still ongoing at the time, the
k'28 cell voltage could dip even
further below the "allowable value" of 2.07 Vdc and render the
battery immediately inoperable.
This led the licensee to develop
contingencies
to help avoid
a TS required
shutdown.
Contingency
plans included the potential
replacement
of the affected cell with
another
.from one of the non-safety station batteries.
This option
would involve a dedication
process for the non-Class
1E cell
and
would require the erecting of heavy steel
equipment
over the
safety-related
battery for cell removal
and installation purposes.
Another option included jumpering out the affected cell
and
performing
an engineering
evaluation to show the battery remained
The later option was discarded
when the supporting
evaluation
would not be ready before the 6-hour
TS shutdown action
statement
expired.
Although the situation corrected itself when the cell voltage
stabilized at 2.25 Vdc following the
24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> recharge,
the
inspector
concluded that the licensee's
overall coordination of
contingency efforts was weak in two areas.
Engineering
personnel
were reluctant to explore more fully the safer option of jumpering
out the battery cell because
of a time constraint.
The other
weakness
was the fact that contingencies
were not even
addressed
until the cell recharge
was half completed,
three days after the
initial surveillance test.
The inspector
concluded that better
coordination of contingency planning
and engineering
resources
would have
been beneficial.
The licensee
has subsequently
developed
an engineering
evaluation
which will allow jumpering out
one
bad cell in the "A" and
"B" emergency batteries.
In addition,
modifications are being developed
which will install spare cells
in the "A" and "B" lE battery
rooms
and have them ready for
immediate installation.
Design
Changes
and Nodifications (37828)
Installation of new or modified systems
were reviewed to verify that the
changes
were reviewed
and approved in accordance
with 10 CFR 50.59, that
the changes
were performed in accordance
with technically adequate
and
approved
procedures,
that subsequent
testing
and test results
met
acceptance
criteria or deviations
were resolved in an acceptable
manner,
and that appropriate
drawings
and facility procedures
were revised
as
necessary.
This review included selected
observations
of modifications
and/or testing in progress.
The following modifications/design
changes
were reviewed:
~ PCR-3995
Emergency Diesel Starting Air Hodifications
12
~ PCR-6841
PCV-8400A Modification
~ PCR-6847
AH-92-1A Bearing Surface
Repair
~ PCR-6852
Containment
Vacuum Relief Actuation Setpoint
Temporary modification PCR-6841
was installed to reduce
containment
inleakage.
As mentioned in
NRC Inspection
Report 50-400/93-07,
.containment
sump inleakage
had increased
to two gpm.
During this
inspection period,
sump inleakage
increased
to approximately four gpm.
On March 22 licensee
personnel
observed
a reduction in the leakage to
approximately 0.2 gpm.
The licensee
also observed that
a back pressure
. control valve,
lBD-8, in the blowdown line for the "A" steam generator
had repositioned to the full'pen position.
The licensee
believes that
this valve backseated
and reduced
any secondary
valve packing leakage
which was present.
The temporary modification was installed to apply
a
false
open signal to the valve's differential pressure
transmitter
controller.
This action did not affect containment integrity since this
valve does not receive
any isolation signals.
No violations or
deviations
were identified.
Fire Protection/Prevention
Program
(64704)
Fire protection activities, staffing and equipment
were observed to
verify that fire brigade staffing was appropriate
and that fire alarms,
extinguishing equipment,
actuating controls, fire fighting equipment,
emergency
equipment,
and fire barriers
were operable.
The inspectors
observed
two fire fighting practice
sessions
which
involved most of the fire brigades.
During the practice
sessions
a fire
brigade
combats
an actual building fire which was fueled
by natural
gas.
These activities occurred at the
Wake County Fire Training Center which
is located adjacent to the plant.
Search
and rescue
techniques
were
also practiced.
The inspector considered
the response
of the fire
brigades to be acceptable
and that the use of appropriate fire fighting
equipment
and fire fighting techniques
were satisfactorily demonstrated.
The licensee
has relocated
the fire brigade turnout/dressout
area
from
the turbine building to the waste processing
building.
The inspector
toured the
new turnout area
and found the conditions to be satisfactory
with adequate
room for the manual firefighting equipment
and turnout
,
clothing.
As discussed
in NRC Inspection
Reports
50-400/91-23
and 50-'400/93-07,
fire brigade staffing duties were assigned
to radwaste
operations
personnel
and roving fire patrol/tours
assigned
to security personnel.
Therefore staffing was not checked during this inspection.
An inventory of control
room Self Contained
Breathing Apparatus
(SCBA)
was performed.
The licensee
maintains
10 SCBA's available with 10 spare
air bottles in the control room.
This equipment
was controlled in
accordance
with procedure
AP-200,
Emergency
Equipment Inventory.
The
13
inspector also checked
the
SCBA inventory in the fire brigade turnout
area.
The licensee
maintains eight SCBA's in the turnout area.
This
equipment
was controlled in accordance
with procedure
ORT-3001, Fire
Equipment Inspection Monthly Interval.
The inspector
found that all of
the observed
SCBA's had recently
been inspected to ensure it was ready
for emergency
use.
The inspector considered
the administrative controls
provided for SCBA'nventory
and inspection to be good.
Essential
Services Chilled Water System Reliability (71707)
During this inspection period, the operability and reliability of the
Essential
Services Chilled Water System
(ESCWS)
was reviewed.
Since
1987, four LERs have
been written on chiller inoperability,
LERs 87-07,
90-03,
90-17,
and 91-04.
These
problems
were reported
because
both
'rains
of ESCWS were inoperable
(one train down for pre-planned
maintenance
and the other train tripped for some reason).
Also, plant
adverse
condition reports
were reviewed
by the inspector
and
an
interview with the system engineer
was held to determine recurrent
chiller problems.
The two
ESCWS units utilize refrigerant to produce
cool chilled water
which is supplied to the cooling coils of the various safety-related
air
handling unit room coolers.
The 752 ton
ESCWS units are oversized for
the low heat loads generated
during normal'lant
oper ation.
Since these
units are also
used during normal plant operation,
the low load has
resulted in some operating
problems in the past.
The two
ESCWS trains
are located within the
same
room and in the
same fire area.
Each train,
however, is spacially separated
as per the fire protection hazards
analysis.
The chiller design incorporates
a 30 minute anti-recycle device to limit
the number of automatic starts, this does not pose
a safety concern
since this, feature is bypassed
on
a safety injection signal.
Various
trips have occurred
on the
ESCWS units since
1987.
In addition,
corrective actions
have
been taken to address
the identified problems
including; operating/maintenance
procedure
enhancements,
training,
and
plant modifications.
Corrective Action
1 Overcurrent Trip
2 Very Low Load
1 High Lube Oil Temperature
1 High Refrigerant
Pressure
No change.
Trip due to bad
overcurrent relay.
Relocated
service water modulating
valves.
Deleted condenser
water low flow
trip.
Added controls for ESW recirculation
pump (P-7).
Calibrated thermocouples.
Added
new filters/regulators for air
supply to expansion
tank.
1
Low Chilled Water Flow
4 Low Oil Pressure
14
Changed
expansion
tank makeup water
source
from fire service to
demineralized
water.
Valves upgraded to stainless
steel
disks
and bodies.
Same
as high refrigerant pressure.
Oil type changed
from C to B.
One hour minimum run time to
determine
proper oil level.
Setpoint
reduced
from 25 psig - 20
pslg.
Since the latest plant modifications during the last refueling outage in
November
1992, the
ESCWS chiller units have operated without additional
problems.
Although the low oil pressure trip setpoint
was reduced in
September
1991,
two trips of this type reoccurred
in July 1992.
In one
of these
cases,
loose relay electrical
connections
were found to have
attributed to the trip signal.
In order to further increase chiller
'eliability,
the licensee
is developing
a plant modification (PCR-6493,
ESCWS Chiller Low Flow/Temperature Trip Alarm) to bypass
most of the
chiller trip signals during
an engineered
safeguards
actuation.'nspector
Followup Item (400/93-08-05):
Follow the licensee's
~
~
~
~
activities to increase
ESCWS reliability.
8.
Review of Licensee
Event Reports
(92700)
The following LER was reviewed for potential generic
impact, to detect
trends,
and to determine'whether
corrective actions
appeared
appropriate.
Events that were reported
immediately were reviewed
as
they occurred to determine if the
TS were satisfied.
LERs were reviewed
in accordance
with the current
NRC- Enforcement Policy.
(Closed)
LER 93-01:
This
LER reported that Operations
Surveillance Test
Procedure
OST-1024,
On-site
Power Distribution Verification, did not
'require operators
to check the position of the
2CB battery input
breakers
to the 7.5
KVa instrument inverters.
The breakers
must
be
closed for the inverters to receive
a backup
DC power supply from their
associated
125-volt
DC busses.
Because of the procedural
omission,
the
breaker positions
had not been verified during the weekly surveillance
test since plant startup,
which constituted
a TS violation.
The
licensee
has revised the procedure to include position verification for
the
2CB and
3CB backup
DC supply breakers.
A copy of the revised
procedures
has
been placed in the required reading for operator training
purposes.
S
15
Licensee Action on Previously Identified Inspection
Findings
(92702
&
92701)
(Open) Violation 400/92-17-02:
Failure to correct
a deficiency with the
emergency diesel
generator starting air system.
The inspector
reviewed
and verified completion of the corrective actions
listed in the licensee's
response letter dated
November 2,
1992.
The
licensee
completed modifications to the starting air systems
which
installed additional filtration and dryer units.
Also, the air system
was blown down with clean dry air and the
PCR process
has
been
removed
from the corrective action program subprogram classification.
Remaining
action to be accomplished
includes
a review of existing
PCRs to ensure
that
an
ACR exists for any adverse conditions.
Exit Interview (30703)
The inspectors
met with licensee
representatives
(denoted
in paragraph
1) at the conclusion of the inspection
on April 19,
1993.
During this
meeting,
the in'spectors
summarized
the scope
and findings of the
inspection
as they are detailed in this report, with particular emphasis
on the Violations, Deviation,
and Inspector
Follow-up Items addressed
below.
The licensee
representatives
acknowledged
the inspector's
comments
and did not identify as proprietary
any of the materials
provided to or reviewed
by the inspectors
during this inspection.
No
dissenting
comments
from the licensee
were received.
Item Number
Descri tion and Reference
400/93-08-01
400/93-08-02
400/93-08-03
400/93-08-04
400/93-08-05
and Initialisms
VIO:
Failure to properly implement plant
procedures,
paragraph 2.c.(1).
NCV:
Failure to maintain appropriate
actuation
setpoints
for the containment
vacuum relief
system,
paragraph 2.c.(2).
DEV:
Performance of non-emergency
safety-
related maintenance
without preplanning,
paragraph'4.a.
IFI:
Follow the licensee's
activities to
restore
the "8" CSIP to operable status
and
review the generic implications of the
pump
shaft failure, paragraph
4.c.
IFI:
Follow the licensee's
activities to
increase
ESCMS rel iabil ity, paragraph
7.
ACR
ASHE
Adverse Condition Report
American Society of Mechanical
Engineers
16
CFR
CSIP
EPT
ESCWS-
gpm
IFI
INWG
ITF
LER
HPT
HST
NRC
OST
pslg
RCS/RC-
TDAFW-
TS
Vac
Vdc
Code of Federal
Regulations
Charging Safety Injection
Pump
Engineering
Performance
Test
Essential
Services Chilled Water System
Emergency Service Water
Final Safety Analysis Report
gallon per minute
Inspector
Follow-up Item
Inches Water Gauge
Inservice Inspection
Inservice Testing
Increased
Testing
Frequency
Licensee
Event Report
Haintenance
Performance
Test
Haintenance
Surveillance Test
Non-Cited Violation
Nuclear Regulatory
Commission
Operations Surveillance Test
Plant
Change
Request
pounds
per square
inch gage
Reactor Auxiliary Building
Residual
Heat
Removal
Self Contained
Breathing Apparatus
'Turbine Driven Auxiliary Feedwater
Technical Specification
Volt alternating current
Volt direct current
Violation