ML16342C651
| ML16342C651 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon |
| Issue date: | 08/15/1994 |
| From: | Kirsch D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | |
| Shared Package | |
| ML16342C649 | List: |
| References | |
| 50-275-94-18, 50-323-94-18, NUDOCS 9408220084 | |
| Download: ML16342C651 (36) | |
See also: IR 05000275/1994018
Text
APPENDIX
B
U.S.
NUCLEAR REGULATORY COHHISSION
REGION I V
Inspection Report:
50-275/94-18
50-323/94-18
Licenses:
DPR-82
Licensee:
Pacific
Gas
and Electric Company
77 Beale Street,
Room
1451
P.O.
Box 770000
San Francisco,
Facility Name:
Diablo Canyon Nuclear
Power Plant,
Units
1
and
2
Inspection At:
Diablo Canyon Site,
San Luis Obispo County, California
Inspection
Conducted:
June
5 through July 23,
1994
Inspectors:
H. Hiller, Senior Resident
Inspector
H. Tschiltz, Resident
Inspector
D. Acker, Senior Project Inspector
G. Johnston,
Senior Project Inspector
D. Corporandy,
Project Inspector
Approved:
D.
. Ki sc
,
ie
,
roJect
rane
F i~/r
Date
Ins ection
Summar
Areas
Ins ected
Units
1 and
2
Routine,
announced
resident
inspection of
onsite
response
to events,
operational
safety verification, plant maintenance,
surveillance
observations,
plant support activities, onsite engineering,
followup engineering,
followup corrective actions for violations,
and
in-office review of licensee
event reports
(LERs).
Results
Units
1
and
2
~0erati one:
Strength:
~
An alert control
room operator
noted
a changing
level
during the performance of an instrumentation
and control
(18tC)
surveillance
where all affected instruments
were not taken out of
service prior to commencing testing.
Operator attentiveness
identified
9408220084
9408l5
ADOCK 05000275
8
the improper performance of a procedural
step during the calibration of
a steam flow channel
and initiated action to secure
from testing
(Section 5.1).
Maintenance:
Weakness:
The failure to perform
a step in
a procedure,
and failure to properly
resolve the resulting procedural
ambiguity during the calibration of a
steam flow channel,
resulted
in a test signal
being improperly inserted
into control circuitry,.resulting in an undesired
change
in steam
generator
level
(Section
5. 1).
This was a'oncited violation.
Inadequate
consideration
was given to the potential
impact of the change
in charcoal
sample analysis
on charcoal
adsorber
bed operability and
a
ventilation damper design
change
on charcoal
adsorber
bed in-service
hours.
The design
change
involved the replacement
and testing of
auxiliary building ventilation damper position switches.
During the
installation of the design
change,
the auxiliary building ventilation
charcoal
adsorber
bed remained
in service.
As
a result of delays during
the modification and associated
testing,
the Technical
Specifications
(TS) required
number of hours of service
between
samples
was exceeded
(Section 5.2).
'This was
a noncited violation.
Strength
I'uring
two separate
activities,
the guality Assurance
organization
identified deficiencies
in a procedure
which prevented
four residual
heat
removal
from being full-stroke exercised
during
the last Unit 2 cold shutdown
(Section 3.2)
and identified
nonconservative
throttling of component cooling water
(CCW) flow to
centrifugal
charging
(CC)
pump coolers
(Section
6. I).
Weakness:
ASME Section
XI inservice testing requirements
were not properly
implemented
in
a surveillance test procedure,
which resulted
in failure
to accomplish required full-stroke testing of foUl
RHR system
check
valves during the last Unit 2 cold shutdown period (Section 3.2).
This
was
a Level
IV violation.
Nonconservative
errors
in an engineering calculation resulted
in
unacceptably
low CCW flow to the
CC pump coolers.
This low flow rate
was caused
by improper, positioning of cooling water throttle valves.
The reduced
CCW flow would have resulted
in exceeding
the maximum
allowable
pump bearing oil temperatures
during design basis
accident
conditions.
Concern over the throttling of
CCW flow had
been raised
by
the li.censee guality Assurance
organization
in 1990;
however,
the issue
was inadequately
resolved
at that time (Section
6. 1).
Strength:
Overall, plant support
performance
was
good during the inspection period
and
remained
unchanged
from the last period.
Inspectors
observed that
housekeeping
practices
in contaminated
areas
were generally
adequate,
and
could
be improved.
Summar
of Ins ection Findin s:
~
Violation 323/94-18-01
was identified (Section 3.2).
.
Noncited Violation 323/94-18-02
was identified (Section
5. 1).
Noncited Violation 323/94-18-03
was identified (Section 5.2).
Inspection
Followup Item 323/93-30-01
was closed
(Section 8. 1).
Violation 323/94-11-01
was closed
(Section 9.1).
LERs 275/94-14,
275/94-10,
and 275/93-12,
Revisions
0,
1,
and
2 were
closed
(Section
10).
Attachments:
~
Attachment
1
Persons
Contacted
and Exit Meeting
~
Attachment
2
0'
DETAILS
1
PLANT STATUS
(71707)
1.1
Unit
1
Unit
1 operated
at
100 percent
power during the entire report period.
1.2
Unit 2
Unit 2 operated
at
100 percent
power for the entire report period,
except
on
July 9 when power was curtailed to 90 percent for the performance of turbine
valve testing.
2
ONSITE RESPONSE
TO EVENTS
(92701
and
93702)
2. 1
Brush Fire Outside of the Protected
Area
On June
22,
1994,
the licensee
declared
an Unusual
Event
(UE) at 2:40 a.m.
(PDT) due to
a grass fire approximately
100 yards outside of the protected
area.
The fire was located
on the hillside east of the plant
and
came within
approximately
100 yards of the
500
KV transmission
lines.
The fire burned
several
acres of grassland
to the south of the
500
KV transmission
lines
and
to the 'northeast of the Nuclear
Power Generation
warehouse.
The fire was
caused
by an electrical
arc at connections
on
a
12
KV power line, independent
of plant related
loads.
The operations
department
isolated the power to the
line in the process of fighting the fire.
Permanent
removal of power to the
12
KV line was planned
as
a corrective action for a previous grass fire but
had not been completed.
The licensee notified the California Department of
Forestry
who responded
to fight the fire with the licensee's fire response
team.
The fire was reported to be out and the unusual
event terminated
at
5:15 a.m.
Conclusion
The fire did not at any time pose
a significant threat to the safe
operation of the facility.
Licensee
response
and declaration of a
UE appeared
appropriate
and well coordinated.
However, the licensee's
corrective actions
for a previous similar event
had not been aggressive
enough to preclude
recurrence.
2.2
Potential to Over ressurize
the
S stem
~Back round
During the Unit
1 outage
on Hay 1,
1994, while
RHR flow was
throttled at the
pump discharge
due to low core decay heat loads,
the licensee
inadvertently pressurized
the
RHR system to 605 psig, while the reactor
coolant system
(RCS)
was solid.
The licensee
determined that
no design
margins
had
been
exceeded
by that event.
However,
since the potential to
reach
RHR system pressure
over 600 psig
had not been anticipated,
the licensee
initiated further analysis of the vulnerabilities of the
RHR system during
throttled flow operations.
As
a result of further analysis,
the licensee
determined that, within the
operational
controls of the
RHR and
RCS, it would have
been possible
to have
pressurized
the
RHR heat exchanger
to 675 psig
a pressure
greater
than the
design
pressure
of 600 psig
and greater
than the
ASNE code allowable of
110 percent of design
pressure
(660 psig).
The concern is isolated to the
heat
exchanger,
since the piping, instrument 'tubing,
and components
such
as
valves all have design
pressures
or ASNE code allowables
above the
675 psig
limits.
The licensee
determined that the
RHR heat
exchanger
was never subjected
to
pressure
above that allowed by ASNE code.
Also, the licensee
determined that
the vulnerability to overpressurize
the
RHR system
was brought about
by
a
failure to properly consider
the combined effects of the
pump discharge
head
and suction pressure,
while discharge
flow was throttled
and while the
RCS was
above
atmospheric
pressure.
The licensee
has initiated
a nonconformance
report
and plans to correct the
vulnerability by operationally restricting the
use of throttled
RHR flow to
those
cases
in Node
6 where the
RCS is vented
and, therefore,
not able to
transfer excessive
pressure
to the
RHR system.
Conclusion
The licensee
had not properly understood
the potential effects of
RHR pump discharge
pressure
under throttled
RHR flow conditions with the
not vented.
There were
no negative effects
on plant equipment,
and corrective
action appeared
appropriate.
Because
the worst-case
effects of this event
were within ASNE code allowable limits, this issue
was considered
of minor
importance,
3
OPERATIONAL SAFETV VERIFICATION
(71707)
3. 1
Failure to Remove Caution
Ta
On June
27,
1994, during
a walkdown of the Unit
1 pipe rack area,
~ the
inspector noted
a caution tag which was
hung for- a surveillance
in April 1994
during the Unit
1 refueling outage.
The inspector
questioned
the purpose of
the caution tag.
The caution tag was attached
to Valve Air-I-1-4351 for the
performance of Surveillance
Test Procedure
(STP)
I-4-PCV-20,
"10% Steam
Dump
Valve PCV-20 Calibration," which was completed
on April 22,
1994.
STP I-4-PCV-20, Step 8.5. l.c contains,
instructions for hanging the caution
tag,
and Step 8.5.3.c directs the technician to close vent Valve AIR-I-1-4351,
restore
the vent valve test
cap,
and
remove the caution tag.
The step
had
been initialed as being complete
and verified and initialed by
a separate
individual.
Following identification of the inspector's
concern,
the vent
valve, AIR-I-1-4351, was verified to be
open with the test
cap restored.
Investigation revealed that there
was
an additional
clearance
hung
on valves
within the boundaries
of this procedure
at the time the surveillance
was
performed,
and that the additional
tags
were
a potential
source of confusion
during the system restoration portion of the surveillance.
The licensee
has
initiated
an Action Request
to document, this problem,
which appeared
appropriate.
0
Conclusion
The failure to remove the tag
appeared
to have
been
an
administrative error with no safety significance
in this instance,
since plant
configuration control
appears
to have
been maintained.
However, this does
not
lessen
the significance of two people
improperly initialing the completion
and
verification of the procedural
step without completing all of the required
actions.
The
NRC will review the licensee's
response
to the Action Request
and the resolution of this problem.
3.2
RHR Check Valve Inservice Testin
Backcaround
During
a licensee
quality organization
review of STP V-4B,
"Functional Test of the
ECCS Check Valves at Cold Shutdown," it was noted that
the recorded
data did not verify the required
2200
gpm flow through
RHR heat
exchanger
discharge
2-8742A and 2-8742B.
During the
surveillance,
a bypass
flow path allowed
an unmeasured
amount of the flow to
be diverted
around the Valves 2-8742A and 2-8742B.
Further investigation of
.
the testing requirements
revealed
the specified flow rate of 2200
gpm was less
than the system design flow rate
and, therefore,
would not accomplish
the
required full-stroke testing of the valves.
This procedural
deficiency
affected
both
RHR heat exchanger
discharge
check Valves 2-8742A and 2-8742B
and the
RHR pump discharge
check Valves 2-8730A and 2-87308.
Following the
discovery of the inadequate
testing
on June
23,
1994,
the licensee
entered
into TS 4.0.3 for Unit 2.
In this situation,
T.S. 4.0.3 allowed the action
requirements
of TS 3,0.3 for both
RHR trains inoperable to be extended for up
to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
Full-stroke testing through the four aforementioned
RHR check valves is
required
by TS 4.0.5.a.
specifies
the inservice surveillance
requirements
of ASME Code Class
1, 2,
and
3 components
shall
be in accordance
with Section
XI of the
ASME Boiler and Pressure
Vessel
Code requirements.
Unit
1 valves
were not affected since all cold shutdown periods
were within
3 months of refueling outage full-stroke exercising.
Section
XI of the
Code Subsection
IWV-3522 requires full-stroke check valve exercising
where the
interval since previous
shutdown testing
has
been
3 months or greater.
During refueling outages,
the full-stroke testing of the check valves is
accomplished
by STP V-4A, "Functional Test of RHR Check Valves."
STP V-4A
accomplishes
the full-stroke tests
by passing full RHR design flow through
heat
exchanger
discharge
check Valves 8742A and 8742B and
RHR pump discharge
check Valves 8730A and 8730B.
Effect of Condition on Safet
Function
The licensee
requested
NRC enforcement
discretion
be exercised for the performance of cold shutdown full-stoke tests
of Unit 2
RHR pump discharge
and Unit 2
RHR heat exchanger
check
valves until the next Unit
2 cold shutdown,
and
no later than the next
refueling outage
(2R6).
The licensee
evaluated
RHR system
response
during the
cold shutdown period
and previous test results to provide the
NRC with
justification for continued operation.
The
NRC exercised
enforcement
discretion,
to not enforce
compliance with TS 4.0.3 until
a temporary relief
request
was processed
by the
NRC, verbally at 6:35 p.m.
EDT on June
24,
1994,
0
followed by letter
on June
28,
1994 (Notice of Enforcement Discretion 94-6-
011).
The temporary relief from ASME Section
XI cold shutdown full-stroke
requirements
for the four Unit 2
was
approved
by the
NRC
letter dated July 11,
1994.
Conclusion
Failure to properly implement inservice testing requirements
in
V-4B=- resulted
in failure to full-stroke test Unit 2
RHR heat
exchanger
discharge
check Valves 2-8742A and 2-8742B
and
RHR pump discharge
check
Valves 2-8730A and 2-8730B during the most recent cold shutdown period.
Failure to full-stroke these
RHR check valves during cold shutdown periods
was
a violation of TS 4.0.5.a,
which requires
inservice testing to be performed in
accordance
with Section
XI of the
ASME Boiler and Pressure
Vessel
Code for
ASME Code Class
1,
2 and
3 pumps
and valves
(323'/94-18-01).
This is
a
Severity
Level
IV violation.
4
PLANT MAINTENANCE
(62703)
During the inspection period,
the inspector
observed
and reviewed selected
documentation
associated
with maintenance
and problem investigation activities
listed below to verify compliance with regulatory requirements,
compliance
with administrative
and maintenance
procedures,
required quality assurance
and
quality .control department
involvement,
proper
use of safety tags,
proper
equipment
alignment
and
use of jumpers,
personnel
qualifications,
and proper
retesting.
Specifically, the inspector witnessed
portions of the following maintenance
activities:
Unit
1
~
Diesel
Generator
1-1 Fuel Oil Level Control Valve (LCV-88) Maintenance
~
Eagle
21
Loop Processor
Board Replacement
~
Diesel
Generator
1-1 Overcrank Alarm Troubleshooting
Unit
2
~
Spent
Fuel
Pool
Swing Gate
Seal
Replacement
~
Spent
Fuel
Pool
Pump 2-2 Maintenance
Conclusion
The inspected
maintenance
activities appeared
to have
been
performed properly.
Administrative and maintenance
procedures
appeared
adequate
and were followed.
There
was appropriate quality assurance/quality
control department
involvement.
Technician
knowledge
and understanding
of the
activities appeared
appropriate
during discussions
involving the various
activities.
Radiation protection practices
appeared
appropriate.
0
5
SURVEILLANCE OBSERVATIONS
(61726)
Selected
surveillance tests
required to,be performed
by the Technical
Specifications
were reviewed
on
a sampling basis to verify that:
(1) the
surveillance tests
were correctly included
on the facility schedule;
(2)
a
technically adequate
procedure
existed for performance of the surveillance
tests;
(3) the surveillance tests
had
been
performed at
a frequency specified
in the
TS;
and
(4) test results satisfied
acceptance
criteria or were properly
dispositioned.
Specifically, portions of the following surveillances
were observed
by the
inspector
during this inspection period:
Unit
1
~
TP TB-9423;
Centrifugal
Charging
Pump
1-2
CCW Flow Measurements
Unit
2
STP M-4;
Routine Surveillance
Test of the Auxiliary Building Safeguards
Air Filtration System
STP I-12B;
Channel
Calibration
Feed
Flow, Steam
Flow
and
Steam
Pressure
Channels
5. 1
STP I-12B
Channel
Calibration
Feed
Flow
Steam
Flow and
Steam
Pressure
Channels
On July 13,
1994, during surveillance testing which calibrates
pressure
and steam flow analog
channels,
and associated
circuitry, two steam
flow channels
were not removed
from service prior to inserting simulated
inputs to obtain "as-found" readings.
As
a result,
2-2
experienced
changes
in level
and feed flow.
A control
room operator,
aware of
the ongoing testing,
noted the changes
in parameters
associated
with Steam
Generator
2-2 testing
and initiated action to secure
from the testing
and
restore
system parameters.
To accomplish the surveillance testing,
several
procedures
were utilized
including:
~
STP I-12B1;
Removal
From Service
Feedflow,
Steamflow
and
Pressure
Channels'TP
I-12B3; Calibration Analog Electronics
Pressure
(Flow Compensating)
STP I-12B4; Calibration Analog Electronics
Feedflow
0
STP I-12B6; Calibration - Comparators
Feedflow,
Steamflow
and Pressure
Channels
STP I-12B1 provides procedural
guidance for removal of a steamflow or feedflow
channel
from service.
The technician misunderstood
the applicability of the
step concerning
the steamflow instrument,
since the instruments
which were
being calibrated
were
pressure
and feedflo'w.
Therefore,
the
technician omitted removing the steamflow channels
from service.
When
preparing to take the "as-found". readings,
the technician
questioned
the
need
to take data for the steamflow instrument since this instrument
was not being
calibrated.
The technician
stopped
the procedure
and discussed
this with his
foreman.
The foreman did not see
a problem with obtaining the data.
It was
not communicated
that the steamflow instrument
had not previously been
removed
from service..
During the performance of the "as found" trip and reset
values
for a high steam flow comparator,
simulated
steam flow inputs were inserted.
The response
of the Digital Feedwater
Control
System
and the resultant
change
parameters
was noted
by the con-.rol
room operator,
who
stopped
the surveillance.
Conclusion
The procedural
step which removes
the steam flow instrument
from
service
was read
and reviewed,
but the incorrect decision
was
made.
The
licensee
is revising the surveillance
procedure
requirements
for removal of
these
instruments
from service for maintenance
and testing.
Prompt operator
response
to changing
parameters
prevented
an improperly
performed surveillance
from impacting plant operation.
Plant equipment
was
not negatively affected.
The failure to adequately
plan
and perform the
surveillance is
a violation of TS 6.8. 1, which states,
in part, that written
procedures
shall
be established,
implemented,
and maintained
covering
applicable .procedures
recommended
in Appendix A of Regulatory
Guide 1.33,
Revision 2, dated
February
1978.
Appendix
A of Regulatory
Guide 1.33,
Revision
2 recommends
procedures
covering surveillance testing;
preventative
maintenance;
and startup,
operation,
and shutdown of safety-related
systems.
Contrary to this requirement,
on July 12,
1994;
steam flow instruments
were
not removed
form service prior to testing
as required
by Step 6.2 of
,
STP I-12BI.
Since this violation was identified by the licensee,
and other
criteria of Section VII.B(2) of the Enforcement Policy were satisfied, this
.
violation was not cited (323/94-18-02).
5.2
STP M-4
Routine Surveillance Test of the Auxiliar Buildin
Safe uards
Air Filtration
S stem
~Back round
Ventilation system charcoal
adsorber
beds
are required to be
periodically sampled
to verify that carbon allows only a small percentage
of
methyl iodide penetration.
Previous
samples
had
been
analyzed
in accordance
with ASTM D-3803-79,
"Standard
Test Method for Nuclear Grade Activated
Carbon."
NRC Information Notice
( IN) 87-32 identified 'problems with the test
methodology in ASTM D-3803-79.
ASTM D-3803-89 is recognized
by industry
as
being
a more accurate
analysis of methyl iodide penetration.
The licensee,
after performing
a review of ASTM D-3803-89,
adopted
the revised
standard for
0
'
-10-
the analysis of charcoal
bed samples.
The revised version .was considered
acceptable
since it provided
more conservative
results
than existing
ASTM D-3803-79 requirements,
The
new analysis,
performed at
a lower
temperature,
reduces
the reaction rate
between
the charcoal
and the iodine
and,
as
a result,
increases
the organic iodine penetration
and provides
a more
representative
indication of charcoal
performance
during
an accident.
The
licensee
adopted this updated
method of analysis for the first time for the
Unit
1 charcoal
samples
taken during Refueling Outage
1R6.
R'esults of Unit
1
charcoal
analysis
indicated
a much higher percentage
of methyl iodide
than the previous
samples.
The licensee's
decision to implement
the revised
standard test method for nuclear grade activated
carbon is viewed
by the
NRC as proactive
and positive.
Charcoal
Bed Service
TS 4.7.6. I.c requires
the licensee
to obtain
a charcoal
sample after each
720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of ventilation flow through the auxiliary building
ventilation system
(ABVS) charcoal
bed.
In the past,
the licensee
has
normally performed
these
samples
during outages.
During the current- Unit 2
'perating
cycle,
an unexpectedly
high number of in-service
hours
accumulated
on the charcoal
adsorber
bed during the installation of a damper position
switch design
change.
To support the design
change installation, it was
necessary
to operate
the Unit 2 auxiliary building ventilation in safeguards
mode,
exhausting
through the charcoal
adsorber
bed.
Accumulation of in-
service
hours during the previous refueling outage,
combined with delays
in.
the accomplishment of the design
change,
resulted in the charcoal
adsorber
bank remaining in service for longer than anticipated.
Charcoal
Bed Surveillance
During the routine surveillance test of the
auxiliary building safeguards
air filtration system,
performed
on June
11,
1994,
the licensee identified that the charcoal
adsorber
bed
had
been in
service for over 780 hours0.00903 days <br />0.217 hours <br />0.00129 weeks <br />2.9679e-4 months <br />.
If the
ASTM D-3803-89
sample results
indicated
unacceptably
high methyl iodide penetration,
such results
would require
declaring the charcoal
adsorber
bank inoperable
and replacing the charcoal
within a 24-hour period.
Part of the scope of STP M-4, "Routine Surveillance
Test of the Auxiliary
Building Safeguards
Air Filtration System," is to verify that operation of the
charcoal
adsorber
bank
has not exceeded
720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> since the last laboratory
analysis of a representative
sample.
The
NRC identified that the
procedure
is deficient in that it does
not preclude
exceeding
the
720 service
hours
between
samples.
TS 4.7.6. l,c requires that the laboratory
sample results
be verified within 31
days after sampling.
The licensee
determined that it would be possible to
comply with the sample results
time requirements,
in this particular
situation,
by calculating the date at which the charcoal
adsorber
bed exceeded
720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of service
and
assuming that the 31-day period for obtaining the
results
started
on that date.
Evaluation of Charcoal
Sam le Results
After obtaining the initial sample
results for the Unit 2 auxiliary building charcoal
adsorber
bed,
which
0
revealed
an increase
in the methyl iodide penetration,
evaluations
of the
operability of other charcoal
adsorber
beds
were not immediately performed.
Following receipt of confirmatory sample results,
the licensee
concluded that
it was likely that the Unit 2 Fuel Handling Building (FHB) E-5 charcoal
bed
was inoperable
and declared it as such.
In the interim period,
between
obtaining the first and
second
sample results,
spent fuel
was
moved in the
Unit 2 spent fuel pool with the
FHB E-5 charcoal
bed in service.
The licensee
has
scheduled
replacement
of the
FHB E-5 charcoal
in the near future, although
analysis of the charcoal
sample
has not been completed.
Licensee
Nana
ement
Involvement
After the discovery that the Unit 2 auxiliary
building charcoal
adsorber
bed exceeded its sample periodicity, thus requiring
a charcoal
sample
and analysis, it was evident that licensee
management
suspected
that sample results
would be
above the allowed limit for methyl
iodide penetration.
Nore timely evaluation of the initial Unit
1 charcoal
sample results
could have alerted
the licensee of the significance of those
results
regarding
the performance of other charcoal
beds.
The licensee
has
completed
a review of the operational
status of all remaining safety related
ventilation charcoal
beds.
The
FHB E-5 charcoal
bed
has
been declared
and the licensee
has preliminarily evaluated all others
as
This evaluation
was
based either
upon the time the
bed
has
been in
service
since charcoal
replacement
and previous
ASTN D-3803-79
sample
analyses
or sample
analyses
using the
ASTN 0-3803-89
method.
In. addition, the licensee
has initiated procedures
to closely track charcoal
bed inservice
hours to
prevent exceeding
required
sampling intervals in the future,
Safet
Si nificance
The licensee's
analysis of the as-found condition
concluded that the Unit 2 auxiliary building charcoal
bed iodine penetration
was outside of the design basis.
This was reported to the
NRC in a 4-hour
nonemergency
report
made
on July 7,
1994.
The licensee
has since corrected
the condition by replacement
of the charcoal
bed.
Conclusion
The licensee's
procedures
for verification of charcoal
adsorber
bed operability did not ensure that charcoal
samples
were obtained at the
specified periodicity.
The failure to implement
a procedure
which ensures
that the charcoal
adsorber
bed is sampled
at the required periodicity is
a
violation of 10 CFR Part 50, Appendix 8, Criterion V, which requires that
activities affecting quality be prescribed
by procedures
appropriate
to the
circumstances
and shall
be accomplished
in accordance
with established
procedures.
Since this violation was identified by the licensee,
and other
criteria of Section VII.B(2) of the Enforcement Policy were satisfied, this
violation was not cited (323/94-18-02).
6
ONSITE ENGINEERING (37551)
6. 1
Insufficient
CCW Flow to
Pum
Coolers
~Back round
The
pump includes five component
coolers
wi>> ch are cooled
by
CCW:
a gear oil cooler,
lube oil cooler,
two seal
coolers,
and
a seal
plate
cooler.
Each cooler
has
an upstream
CCW isolation valve.
The lube oil
-12-
cooler,
gear oil cooler,
and seal
plate cooler have
a
common discharge
throttle valve which, until recently,
was throttled to control the flow to the
coolers.
In 1990,
a licensee
Safety
System Functional Audit and
Review
(SSFAR) questioned throttled
CCW flow to the
CC pumps.
The audit
raised
the concern that throttled
CCW flow may not provide design
basis flow
rates
to the individual components
during accident conditions
and heat loads.
The resolution of this audit finding accepted
the throttled
CCW condition
and
.
was based,
in part,
on
an engineering calculation which contained
two
nonconservative
assumptions.
The licensee
now considers
the resolution of the
audit finding,
and acceptance
of throttled
CCW flow, to be in error.
On June
29,
1994,
a I-hour nonemergency
report was
made to the
NRC regarding
past operability of the
CC pumps.
The report stated that, previously,
flow to the
CC pump coolers
had
been throttled during normal operation.
This
would not have'rovided
adequate
cooling to the
CCW gear oil cooler during
a
design
basis accident.
CCW was throttled to maintain lube oil temperatures
within the vendor
recommended
temperature
band
and, therefore,
maintain proper
viscosity during normal
CC pump operation.
Recent licensee
investigation of
pump lube oil characteristics
revealed that there is very little change
in
viscosity, for the type of oil used,
over the entire range of possible
temperatures.
Therefore, throttling
temperatures
was
no longer
a concern.
Pum
Prior to the I-hour nonemergency
report, preliminary
CCW system flow rate testing
had
been completed.
The tests
indicated
potentially insufficient
CCW cooling to the
CC pumps under design basis
conditions.
After the preliminary testing,
the
CCW throttle valve on the
common discharge
header of the
CC pump gear oil, bearing oil, and seal
plate
coolers
was fully opened.
A prompt operability assessment
was initiated to
document
the adequacy
of the existing cooling flow with the
common outlet
throttle valve fully open.
I
The licensee
is continuing testing
and calculations
to support proper
adjustment of flow to each of the coolers.
Flow is being measured
by an
acoustic
sensor
instrument,
since the system
does not have installed equipment
which measures
the flow rates.
The throttling of
CCW flow during testing is
accomplished
using the throttle valves to individual coolers.
The licensee
plans to use these test results to determine final valve throttle positions
for establishing
adequate
flow rates to the
CC pump components
cooled
by
CCW.
Conclusion
The licensee
resolution of issues
raised
in the
1990 safety
system
functional audit
and review regarding
the
CCW system incorrectly accepted
the
adequacy of the existing throttled cooling flow,
The initial decision" to
throttle. the
CCW supply to the
CC pumps
does not appear to have
been properly
reviewed prior to establishing
the throttled configuration procedure.
The
licensee's
interim actions,
which have
been
communicated
to the
CC pump
vendor,
appear to provide adequate
cooling to the
CC pumps.
Further
NRC
review of this issue will be concluded during the review of the Licensee
Event
Report
(LER).
0
-13-
7
PLANT SUPPORT ACTIVITIES
(71750)
The inspectors
evaluated
plant support activities
based
on observation of work
activities, review of records,
and facility tours.
The inspectors 'noted the
following during this evaluation.
7. 1
Fire Protection
During inspection of fire barrier penetration
seals,
the .inspectors
observed
a
break in the sealed barrier in the floor of the Unit 2 cable spreading
room.
The inspectors
learned that the breach
was
a resul,t of work ongoing in
preparation of installing conduit for part of the
new Eagle
21 reactor
protection
system,
scheduled for completion during the upcoming Unit 2
refueling outage.
The licensee
was implementing the appropriate
hourly fire
watch compensatory
measures
for the breach,
7,2
Radiation Protection Controls
The inspectors
periodically observed
radiological protection practices
to
determine whether the licensee's
program was being implemented
in conformance
with facility policies
and procedures
and in compliance with regulatory
requirements.
The inspectors
also observed
compliance with radiation work
permits,
proper wearing of protective equipment
and personnel
monitoring
devices,
and personnel
frisking practices.
Radiation monitoring equipment
was
frequently monitored to verify operability and adherence
to calibration
frequency. 'everal
resident
inspector tours in the radiological control
area
revealed
minor cases
of deficient contamination control practices
in the
140-foot level of the
FHB surface
contaminated
areas
(SCAs).
On several
occasions,
an area
where work was being performed
on ventilation components
and ducting was poorly controlled.
At several different locations,
material
from inside the
SCA crossed
over the
SCA boundary.
Similar deficiencies
had
been previously noted in the
same
area
on several prior occasions.
These
deficiencies
and the past
poor performance
was point'ed out to
plant'anagement,
and action
was initiated to correct the deficiencies.
Conclusion
It was apparent
in each
instance that action
had
been initiated to
correct the deficiency,
but the corrective action
was not always
adequate
to
prevent recurrence.
Because prior corrective action did not result in
effective long-term resolution,
additional
management
involvement is needed.
7.3
Plant Housekee
in
The inspectors
observed
plant conditions
and material/equipment
storage
to
determine
the general
state of cleanliness
and housekeeping.
Housekeeping
in
the radiologically controlled area
was evaluated
with respect
to controlling
the spread of surface
and airborne contamination.
On one plant tour the inspectors
noted
a small puddle of liquid on the floor
near the Unit
1 Reciprocating
Charging
Pump 1-3.
The inspectors
informed
Health Physics
and noted
on their next tour that the puddle
was gone.
-14-
The inspectors
observed
a weakness
in general
plant cleanliness
in some areas.
'his
was of particular concern
in the radiologically controlled areas of the
plant.
Two examples
were
as follows:
~
Rubber gloves
and glove liners were left within the
SCA on the skid of
Pump 2-1.
~
A significant portion of the floor in the Unit 2 turbine-driven
auxi,liary feed
pump room was stained
due to
a previously leaking
component.
7.4
~Securit
,The inspectors
periodically 'observed
security practices
to ascertain
that the
licensee's
implementation of the security plan
was in accordance
with site
procedures,
that 'the search
equipment
at the access
control points
was
operational,
that the vital area portals
were kept locked
and alarmed,
and
that personnel
allowed access
to the protected
area
were
badged
and monitored
and that monitoring equipment
was functional.
The inspectors
noted
no
problems
in this area during this inspection period.
7.5
Conclusion
Overall, plant support
performance
was good during the inspection period
and
remained
unchanged
from the last period.
Inspectors
observed
that
housekeeping
practices
in contaminated
areas
were generally
adequate,
and
could
be improved.
8
FOLLOWUP ENG INEERING (92903)
8.1
Closed
Followu
Item 323 93-30-01: Definition of Safe
Shutdown
Earth
uake
During review of SSE requirements
for Diablo Canyon,
an inspector
noted that.
SSER 7, dated
Hay 1978,
and
SSER 31, dated
June
1991,
implied that the
NRC
considered
that the
SSE for Diablo Canyon
was the
maximum credible force of an
generated
from the Hosgri fault, with a peak ground
acceleration
(PGA) of 0.75g.
However,
the licensee's
Updated
Final Safety
Analysis Report
(UFSAR), Section
3, indicated that the
SSE for Diablo Canyon
was the
DDE, with a
PGA of 0.4g.
The inspector did not identify any failure
of the licensee
to comply with any
NRC seismic requirements.
The inspector
initiated
a followup item for further
NRC review of the definition of SSE at
Diablo Canyon.
Subsequent
to the initial inspection,
the
NRC staff reviewed the seismic
licensing basis for Diablo Canyon
and clarified that the
SSE for Diablo Canyon
was the double design
(DDE) as described
in the
UFSAR, Section 3.
The
NRC staff noted that all
new modifications required analysis for both the
DDE and Hosgri earthquakes.
The
NRC staff also noted that the
NRC had
0
-15-
required the licensee
to ensure
they could safely shutdown
both units
following either
a Hosgri or
Based
on
NRC staff's
agreement
with the licensee's
definitions for the
SSE at Diablo Canyon,
the inspector
concluded that the followup item was resolved.
9
FOLLOWUP
ON CORRECTIVE ACTIONS FOR VIOLATIONS
(92702)
9.1
Closed
Violation 50-323 94-11-01:
Failure to Plan
and Perform
Maintenance
in Accordance with Written Procedures
The
NRC identified
an instance
where the licensee failed to establish
a
clearance
during
a repair of the Unit 2 reactor coolant
system safety
injection inlet to
Loop 2-3, which was the subject of a citation with NRC
Inspection
Report 50-323/94-11.
In
a letter dated
June
20,
1994,
the licensee
acknowledged
the violation and stated that corrective action
had
been
completed for the specific instance cited
and that further action to prevent
recurrence
had
been initiated by revision of the licensee
procedure
AP C-4S1,
"Temporary Modification Control - Plant
Jumpers
and
METE."
The inspector
reviewed
and verified these actions.
The licensee's
actions
appeared
to be
appropriate
and properly implemented.
10
IN-OFFICE REVIEW OF
LERS
(90712)
The following LERs were closed
based
on in-office review:
~
275/94-14,
Revision
0
Unplanned
DG Start
(ESF Actuation)
Due to
Shorting Indicating Lights
275/94-10,
Revision
0
Main Bank Phase
"C" Transformer
Degraded
Condition
275/93-012,
Revision
0
ASW System Potentially Outside
Design Basis
275/93-012,
Revision
1
ASW System Potentially Outside Design Basis
275/93-012,
Revision
2
ASW System Potentially Outside
Design Basis
1
PERSONS
CONTACTED
ATTACHMENT 1
Licensee
Personnel
G.
N
- W
- R.
T.
J.
- G
S.
W.
S.
- B
- J
- C
- C
J.
R.
J.
- K
'.
M.
J.
- D
M.
p.
S.
B.
- J
D.
D.
D.
- D
M. Rueger,
Senior Vice Pres, ident
and General
Manager,
uclear
Power Generation
8'usiness
Unit
H. Fujimoto, Vice President
and Plant Manager,
Diablo Canyon Operations
P.
Powers,
Manager,
Nuclear equality Services
L. Grebel,
Supervisor,
Regulatory
Compliance
S.
Bard, Director, Mechanical
Maintenance
M. Burgess,
Director,
Systems
Engineering
G. Chesnut,
Reactor
Engineer Supervisor
G. Crockett,
Manager,
Technical
and Support Services
R. Fridley, Director, Operations
W. Giffin, Manager,
Maintenance
Services
D.
Grammer,
Engineer,
Systems
Engineering
'R. Groff, Director, Plant Engineering
D. Harbor,
Engineer,
Systems
Engineering
A. Hays, Director, Onsite equality Control
W. Hess, Assistant Director, Onsite Nuclear Engineering
Services
R. Hinds, Director, Nuclear Safety Engineering
A. Hubbard,
Engineer,
Regulatory Compliance
C. Kelly, Mechanical
Group Leader,
Nuclear Engineering
Services
E.
Leppke, Assistant
Manager,
Technical
Services
J.
McCann,
General
Foreman,
Instrument Maintenance
B. Miklush, Manager,
Operations
Services
D. Nowlen, Director, Instrumentation
and Controls
T. Nugent,
Engineer,
Regulatory
Compliance
R. Ortore, Director, Electrical Maintenance
H. Patton,
Director, Technical
and Support Services
A. Shoulders,
Director, Onsite Nuclear Engineering
Services
P. Sisk, Senior Engineer,
Regulatory
Compliance
W. Spencer,
Power Production
Engineer,
Plant Engineering
R. Stermer,
Engineer,
Systems
Engineering
A. Taggart, Director, Onsite equality Assurance
1.2
NRC Personnel
- M.
- M. Miller, Senior Resident
Inspector
Tschiltz, Resident
Inspector
- Denotes those attending
the exit meeting July 27,
1994.
In addition to the personnel
listed above,
the inspectors
contacted
other
personnel
during this inspection period.
2
EXIT MEETING
An exit meeting
was conducted
on July 27,
1994.
Ouring this meeting,
the
inspectors
reviewed the scope
and Findings of the report.
The licensee
acknowledged
the inspection findings documented
in this report.
The licensee
did not identify as proprietary
any information provided to, or reviewed by,
the inspectors.
ATTACHMENT 2
ACRONYHS
. ASNE
FHB
IN
KV
LER
SCA
SSER
SSFAR
TS
auxiliary building ventilation system
American Society of Hechanical
Engineers
centrifugal
charging
(high head injection)
component
cooling water
double design
fuel handling building
instrumentation
and controls
Information Notice
kilovolts
licensee
event report
peak ground acceleration
system
residual
heat
removal
surface
contamination
area
safe
shutdown
Supplemental
Safety Evaluation Report
safety
system functional audit
and review
- surveillance test procedure
Technical Specification
unusual
event
Updated
Final Safety Analysis Report