ML16342D306
| ML16342D306 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon |
| Issue date: | 05/20/1996 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | |
| Shared Package | |
| ML16342D304 | List: |
| References | |
| 50-275-96-06, 50-275-96-6, 50-323-96-06, 50-323-96-6, NUDOCS 9605280217 | |
| Download: ML16342D306 (26) | |
See also: IR 05000275/1996006
Text
.
Enclosure
2
U.S.
NUCLEAR REGULATORY COMMISSION
REGION IV
Docket Nos:
License
Nos:
50-275,
50-323
Report
No:
50-275/96006,
50-323/96006
Licensee:
Pacific
Gas
and Electric Company
(PG&E)
Facility:
Diablo Canyon
Power Plant,
Units
1
and
2
Location:
Avila Beach, California 93424
Dates:
March
3
April 13,
1996
Inspectors:
M.
D. Tschiltz, Senior Resident
Inspector
S.
A. Boynton,
Resident
Inspector
J.
A. Sloan,
Senior Resident
Inspector,
San Onofre
Nuclear Generating
Station
Approved by:
H. J.
Wong, Chief, Reactor Projects
Branch
E
Division of Reactor Projects
9605280227
960520
ADOCK 05000275
8
.0
EXECUTIVE SUMMARY
Diablo Canyon
Power Plant,
Units
1
& 2
NRC Inspection
Report 50-275/96006,
50-323/96006
This report covers
a 6-week period of resident
inspection,
which incorporated
operational
safety verification, maintenance
observations,
surveillance
observations,
onsite engineering,
and plant support activities.
~0eratinns:
The inspectors
identified the failure to perform
an adequate
channel
check of a cold calibrated pressurizer
level,
an indication which is
located at the dedicated
shutdown panel,
but not required
by Technical
Specification
(TS) (Section Ml.2.2).
The inspectors
identified
a noncited violation involving the in-use
Axial Flux Distribution (AFD) Limits Figure posted
on the Unit
1 control
panel
which exceeded its issued-for-use
period of 30 days without having
been reverified (Section 01.4).
The inspectors
identified
a violation for operators failing to follow
procedural
requirements
by raising Unit
1 reactor
power above
20 percent
(220
MWe) without completing the required procedural
steps
and
prerequisites
(Section 01.3).
Operators
promptly identified and stopped
valve packing leakage
in
excess
of 7 gallons per minute within the time allowed in the TS.
A
prompt operability assessment
was performed which thoroughly addressed
relevant operability issues
(Section 01.2).
Maintenance:
~
Both
an inadequate
surveillance
procedure
and ineffective reviews of the
completed surveillance,
resulted
in the improper performance of the
surveillance of the reactor coolant
system
(RCS) hot leg and cold leg
temperature
indications at the dedicated
shutdown
panel
in January
1996.
This was identified as
a violation (Section M1.2,2).
Inaccuracies
and inconsistencies
within the
UFSAR associated
with the
component cooling water
system,
remote
shutdown instrumentation,
4
kV
power
and the emergency diesel
generators
were noted.
This was
identified as
an unresolved
item (Sections
E7.1)
~
Continued
problems
were noted with the source
range nuclear
instruments
startup rate meters sticking on their low peg.
An Inspection
Followup
Item was
opened
to track the licensee's
long-term corrective actions for
this problem (Section
E1..2).
The licensee's
corrective actions
in response
to
a previous violation
(275/95014-01)
failed to identify the need to reset
the emergency diesel
generators'EOG)
lube oil low temperature
alarm setpoint
(Section
E2. 1).
The licensee
has conducted full-core offloads routinely without having
performed
a safety evaluation
and
as
a consequence
licensee
procedures
did not ensure
that the spent fuel pool temperature
and the time to
offload the core were within the licensing bases.
This was identified
as
an unresolved
item (Section E2.2).
Re ort Details
Summar
of Plant Status
J
Unit
1 began this inspection period at
100 percent
power.
On March 14, the
unit was placed in Mode
3 to facilitate the installation of Auxiliary
Transformer
1-1.
Following installation, Unit
1 was returned to full power
on
March 20,
and remained at full power for the balance of the inspection period.
Unit 2 began this inspection period at
100 percent
power.
On March 12, the
unit was curtailed to 85 percent
power for approximately
5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> at the
request of the system dispatcher.
On April 6, Unit 2 was shut
down for its
seventh refueling outage.
The unit was in Mode
6 at the
end of the inspection
period.
I. 0 erations
01
Conduct of Operations
01. 1
General
Comments
Using Inspection
Procedure
71707,
the inspectors
conducted
frequent
reviews of ongoing plant operations.
In general,
the conduct of
operations
was professional
and safety-conscious;
specific events
and
noteworthy observations
are detailed
in the sections
below.
01.2
S stem
Leaka
e . Unit
1
II
a.
Ins ection
Sco
e
71707
The inspector
reviewed the licensee's
actions regarding
elevated
leakage identified in Unit
1 on March 4.
b.
Observations
and Findin
s
On March 4, at 6:07 a.m., Unit
1 operators
observed
level decreasing
in
the volume control tank.
The leakage
was estimated
to be between
5-7
gpm.
The licensee
promptly investigated
and determined that the leakage
was from the packing gland of the centrifugal charging
Pumps
1-1
and
1-2
flow control Valve
(FCV) CVCS-1-FCV-128.
Operators
opened
valves in the
bypass line and closed
Valve CVCS-1-FCV-128.
At 8: 14 a.m.,
operators
isolated
the
FCV.
They then performed
a
RCS leak rate calculation
and
confirmed that the leak had
been isolated.
As
a compensatory
action,
an
operator
was stationed
near the centrifugal charging
pump in order to
restore recirculation flow in the event it had
become
necessary
to start
the second
pump.
The licensee initiated Action Request
(AR) A0394938 to document
the
event
and the licensee's
prompt operability assessment
(POA)
and to
initiate corrective maintenance.
The inspectors
reviewed the
POA and
determined that it appropriately
addressed
the relevant
TS requirements.
The inspectors
determined
that
TS requirements
were met while the
was isolated
and the bypass line was in service.
Conclusions
Operations
appropriately identified and stopped
the leakage within the
time allowed in the TS.
The
POA was thorough
in addressing
all relevant
operability issues.
Startu
Observations
Unit
1
Ins ection
Sco
e
71707
The inspectors
observed
startup activities in the Unit
1 control
room on
March
17 and
18.
The inspectors
observed
the
use of portions of the
following procedures:
OP L-3, Revision
15,
"Secondary
Plant Startup"
OP L-4, Revision 33,
"Normal Operation
at Power"
OP L-O, Pevision
34,
"Mode Transition Checklists"
OP C-3: II, Revision
17,
"Hain Unit Turbine Startup"
Observations
and Findin
s
The secondary
plant startup
observed
on March
17 was well controlled by
the Senior Control Operator.
Communications
were clear
and the
evolution proceeded
with caution.
Operators
questioned
indications
and
were observed
to use self-verification techniques.
During the secondary
plant startup,
the operators
noted several
weaknesses
with the procedures.
Although these
problems did not appear
to have
any safety consequence,
several
procedural
steps
were written to
require
an exact value rather than
a range of acceptable
values.
Following the evolution operators
submitted
several
pages of comments
which identified areas
where procedural
improvements
could
be made.
Procedure
OP L-3 provides instructions for raising reactor
power from
0 to 20 percent
(approximately
220 HWe).
Procedure
OP L-4 provides
instructions for power changes
between
20 percent
and
100 percent
power.
OP'-3,
Step 6.37 required operators
to proceed
to
OP L-4 after all of
the steps of OP L-3 were complete.
The inspectors
noted that the
operators
had raised
power to 29 percent
the morning of March
18 without
completing the required
steps
in
OP L-3.
The steps that
had not been
completed
were for the alignment of the feedwater
and condensate
system
for operation at power levels of greater
than
50 percent.
Although
there
was
no safety
consequence
for not performing the steps
at that
point in time, the inspectors
were concerned
that operators
did not note
their actions
were contrary to procedures.
Additionally, the
prerequisites
of Procedure
OP L-4 had not been
completed prior to
beginning
some of the steps.
c.
Conclusions
The secondary
plant startup
was well controlled
and operators
provided
numerous
comments for procedural
improvements.
Operators failed to
follow procedures
for raising reactor
power.
Oversight
and direction of
the evolution by the shift foreman did not prevent this from occurring.
The failure to complete all of the requirements
for transition from
Procedure
OP L-3 to
OP L-4 is
a violation of TS 6.8. 1
(VIO 50-323/96006-01).
01.4
Axial Flux Distribution
AFD
Limits Curve
a.
Ins ection
Sco
e
71707
On April 1, the inspectors
conducted
a walkdown of the Unit
1 control
panel to verify operation
in accordance
with TS requirements
and
licensee
procedures.
b.
Observations
and Findin
s
The
AFD Limits Figure posted
on the control
panel
was noted to have
exceeded
the issued-for-use
period of 30 days without having been,
reverified.
Administrative Procedure
AD2. ID1, "Procedure
Use
and
Adherence,"
Step
5. 1. I.b specifies
a maximum in-use period for
procedures
of 30 days
and requires that procedures
in use for longer
than
30 days
be verified to be the current revision
and remarked.
After the inspectors
noted the problem the figure was verified to be
up
to date.
Normally this matter would be considered
a minor issue of low
safety significance
and therefore
would not be discussed
in an
inspection report;
however, this was
a recurring problem which the
inspectors
had raised
in the previous inspection period.
c.
Conclusions
The failure to verify the in-use
AFD Limits Figure posted at the Unit
1
control
panel
every 30 days
as required
by Administrative Procedure
AD2. IDl was identified as
a noncited violation of TS 6.8. 1.
This
failure constitutes
a violation of minor significance
and is being
treated
as
a noncited violation, consistent with Section
IV of the
NRC
Enforcement Polic
(NCV 50-275/96006-02).
02
Operational
Status of Facilities
and Equipment
02. 1
En ineered
Safet
Feature
S stem Walkdowns
Ins ection
Sco
e
71707
tJ
The inspectors
used
Inspection
Procedure
71707 to perform
a detailed
walkdown of accessible
portions of the control
room ventilation system
(CRVS).
The inspectors
also reviewed the applicable portions of the
b.
licensee's
Updated Final Safety Analysis Report
(UFSAR) associated
with
the
CRVS and design criteria memorandum
(DCH) S-23F,
Revision 0,
Change
11, "Control
Room Heating, Ventilation,
and Air Conditjoning
System."
Observations
and Findin
s
The inspectors
noted
on April 8 that the material condition of system
components
and area
housekeeping
of the accessible
portions of the
were generally
good.
A detailed
walkdown of the system configuration
and its components
found no discrepancies
with the current as-built
mechanical
drawings.
The inspectors
reviewed the applicable portions of the licensee's
and the system
DCH and found several
discrepancies
where the documents
did not reflect current design
and operation.
Table 9.4-1 of the
describes
the design
parameters
of the
CRVS filter train including
an
85 percent
removal efficiency by the charcoal filter beds for methyl
an organic form of iodine.
This appears
to be
a typographical
error.
The 85 percent
value is inconsistent
with the listing in fable
9.4-2 for removal efficiency, the licensee's
analysis for determining
postaccident
doses
to control
room personnel,
and the acceptance
criteria in the associated
surveillance
procedure.
Additionally,
Table 9.4-2 referenced
information contained
in Table 9.4-3;
however,
Table 9.4-3
had
been deleted
from the
Review of the
DCM for the system revealed that it had not been
updated
'o
refl,ect the impact of the installation of the third emergency diesel
generator
(EDG)
on Unit 2.
In addition,
11 interim design criteria
memorandum
changes
had
been
made to the
DCH since its original issuance
, in 1992.
However,
these
interim design criteria memorandums
had not
been
incorporated
into the
body of the
DCH and only existed
as
pen-and-ink
attachments,
making it difficult to'xtract technical
information'he licensee
has identified problems with maintenance
of
the
DCHs through its
own self-assessment
program.
Conclusions
The configuration of the
CRVS was in accordance
with the licensee's
UFSAR and the as-built mechanical
drawings'.
Material condition of the i
system
was generally good.
The discrepancies
identified in the
and
DCM were considered
to be of low safety consequence;
however,
they
were indicative of a less-than-effective
pr'ogram to review and update
these
documents.
These failures to update
the
UFSAR are considered
additional
examples of the problem described
in Section
E7. 1 and will be
included in the Unres'olved
Item (URI 50-275/96006-06).
k
08
miscellaneous
Operations
Issues
(92700)
08.1
'
en
Violation 50-275 9428-01:
Failure to follow EDB test procedure.
Following the inadvertent
loss of residual
heat
remover during
IR6
testing,
the
NRC issued
a violation.
In order to track and develop
corrective actions
in the response
to the violation the licensee
issued
a nonconformance
report
(NCR).
The licensee's
response
to the violation
dated
December
9,
1994, detailed corrective actions
which included:
1.
Review and revisi'on of programs that place tags
on main control
boards
to prevent information from being obscured
on in-service
equipment.
2. Revision of Administrative Procedure
OPI.DC12,
"Conduct of Routine
Operations" to:
a.
require that, during refueling outages
where significant
outage activities are in progress,
a dedicated
licensed operator
will be in the control
room with no assigned
duties other than
monitoring overall plant conditions;
b.
define the threshold of operating evolutions
where it is
expected
that the shift foreman
be in. the control
room directly
supervising
the evolution;
and,
c.
chan'ge
the attachment
that describes
tailboard briefings to
place
more emphasis
on the "big picture" discussion.
The licensee
had indicated that the first corrective action review would
be complete
by April 1,
1995,
and
OP1.DC12 would be revised
by
February
1,
1995.
The inspectors
reviewed the changes
to the procedures
discussed
in the
response
to the violation.
Discussions
with the Operations Director
revealed that the corrective actions
associated
with the first action
had not been
completed,
The programs that place tags
on main control
boards
had not been revised
and there
was
no ongoing effort to do so.
The
NCR had
been closed without completing all of the actions
discussed
in the licensee's
response
to the violation.
'he
remaining actions, were subsequently
completed;
however,
they had not
been
completed within the time frame indicated
by the licensee.
The
last revision to OPI.DC12
was completed
in October
1995,
over 8 months
after the date indicated
by the licensee.
The inspectors
concluded that the licensee
had failed to take all of the
actions described
in the response
to the Notice of Violation.
The
failure to complete
these corrective actions is of particular concern
since they were initiated in response
to an incident that involved the
inadvertent
loss of core cooling.
Violation 50-275/9428-01
remains
open
pending further review,of"corrective actions
taken
by the licensee.
r
08.2
Closed
VIO 50-275 95016-01:
(A) failure to follow procedure
during
reactor
vessel
draindown to half-loop operation;
(B) failure to follow
procedure
during operational
checks of the source
range nuclear
instruments.
The,inspector's
reviewed the licensee's
response
to the Notice of
Violation, dated
February
15,
1996,
and discussed
with the licensee
the
corrective actions
taken in response
to Part
A of the violation.
The
inspectors
also verified that the licensee
had completed
the long-term
corrective actions
as stated
in its response.
Associated with this violation, the inspectors
noted in
NRC Inspection
~
Report 50-275/95016 that
a potential
root cause of the violation was
an
ineffective'reevolution tailboard.
The licensee justified the
shortened
tailboard observed
by the inspectors
based
upon discussions
held between
the operators prior to the tailboard.
The licensee
concluded that the prerequisites,
precautions
and limitations had
been
reviewed in these discussions.
However, discussions
of this type did
not meet the licensee's
expectations
for conduct of a tailboard.
The
operations director agreed that informal discussions
are appropriate for
augmenting
operator
knowledge,
but should not be relied
upon in lieu of
conducting
a tailboard.
The inspectors
concluded that the actions
taken
by the licensee
to
prevent recurrence
of the violation appeared
adequate
to address
the
root causes.
Ml
Conduct of Maintenance
Ml. 1
Maintenance
Observations
II. Maintenance
a.
Ins ection
Sco
e
62703
The inspectors
observed all or portions of the following work
activities:
C0142927
Radiography of CVCS-1-RV-8116 Inlet Piping
C0142601
Install/Remove
Ground
Buggy 8 52HF13
C0142875
Radiography of RCP 1-2 diffuser
TP TD-9607
Providing Vital 125-Vdc Power
From SD21, to SD22 Vital
Loads
C0143460
Replace
Eagle
21 Analog Input Board
-7-
b.
Observations
and Findin
s
The inspectors
found the work performed
under these activities to be
professional
and thorough.
All work observed
was performed with the
work package
present
and in active use.
Technicians
were experienced
and knowledgeable of their assigned
tasks.
The inspectors
frequently
observed
supervisors
and
system engineers
monitoring job progress,
and
quality control personnel
were present
whenever required
by the
procedure.
When applicable,
appropriate radiation control
measures
were
in place.
In addition, selected
maintenance
observations
are discussed
below.
H1.1.1
Re ackin
of FCV CVCS-1-FCV-128
Unit
1
a.
Ins ection
Sco
e
62703
The inspectors
observed
portions of the performance of Work Order
(WO) C0142940,
which directed
unpacking
and repacking the
above valve
per Mechanical
Maintenance
Procedure
(MP) M-51.23, Revision
3A.
This
work was required
due to valve packing failure that resulted
in
significant system
leakage
(see Section 01.1).
b.
Observations
and Findin
s
The
WO directed careful
examination of the packing
upon removal to
attempt to determine
the cause of the failure.
The
WO also directed
engineering
personnel
to be present
during the unpacking
and repacking.
The licensee
determined that the lower rings of packing material
were
substantially missing,
but that the upper rings were intact.
The sequence
of steps
in Procedure
MP H-51.23
was to first install all
the packing rings
and then consolidate
the packing.
However,
maintenance
and engineering
personnel
performed consolidation after
installation of the lower two rings.
Procedure
HP H-51.23 allowed the
engineer
to alter the
sequence
based
on job requirements.
During the maintenance activity, the licensee identified
a small bolt in
the drain line for Valve CVCS-I-FCV-128,
and documented
the condition
in
AR A039468039468
The licensee initiated
an investigation of the potential
origin of the bolt.
c.
Conclusions
There
was good engineering
involvement during unpacking,
inspection,
and
repacking of the valve
and procedures
were followed.
Hl. 2
Surveillance
Observations
k
a. 'ns ection
Sco
e
61726
Selected
surveillance tests
required to be performed
by the
TS 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 the 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.
The inspectors
observed all or portions of the following surveillances:
STP R-18, Revision
15,
"Rod Drop Measurement"
STP l-36-S3TTD, Revision
1, "Protection
Set
Time Delay"
P-AFW-11, Revision
1A, "Routine Surveillance
Test of
Turbine-Driven Auxiliary Feedwater
(AFW)
Pump
1-1
STP V-3PI, Revision
13, "Exercising Hain Feedwater
Regulating
Valves
and Bypass
Valves"
STP V-3P2, Revision 7, "Exercising Main Feedwater
Isolation Valves
FCV-438,
439,
440 and 441"
b.
Observations
and Findin
s
The surveillances
reviewed and/or observed
by the inspectors
were
scheduled
and performed at the required
frequency.
The surveillance
test procedures
were technically adequate
and personnel
were
knowledgeable.
The inspectors
also noted that test results
were
appropriately dispositioned.
In addition,
see specific discussion of other surveillances
observed
by
the inspectors
under Sections
H1.2.1, Hl.2,2, H1.2.3,
and H1.2.4.
H1.2.1
Nuclear
Power
Ran
e Incore Excore Calibration
a.
Ins ection
Sco
e
61726
The inspectors
observed partial
performance of Surveillance
Test
Procedure
(STP)
STP I-2D, Revision 39, "Nuclear Power
Range
Incore/Excore Calibration,"
on Channel
D in Unit 1.
The inspectors
reviewed qualification records for the test performer,
and discussed
the
procedural
guidance with maintenance
supervision.
b..
Observations
and Findin
s
The test performer conducted on-the-job training with two less
experienced
technicians.
The test performer
appeared
to be very
knowledgeable of the nuclear instrumentation
.system
and test procedure.
In preparation for taking data for Table SC-I-2D-AI, Attachment 4.4
(T4), the test performer advised
the trainees
to first set the coarse
adjustment for the highest test point so that the fine adjustment
would be near the middle of its range to allow for maximum
flexibility for subsequent
instrument adjustments.
This guidance
was
not specified
in the surveillance
procedure
and the highest test point
was listed in the middle of the data table.
The inspectors
discussed
this with the test performer
and with a
maintenance
general
foreman.
The discussion
revealed that the test
procedure
would work as written, but may not be efficient and
may not
leave the fine adjustment
in the middle of its range.
However,
operators
only need approximately
20 percent of the range for their use
during operations.
The nuclear instrumentation
channel
was
removed
from service for this
test.
The qualification records of the test performer were appropriate
for surveillances
on the nuclear instrumentation
system.
c.
Conclusions
The test performer
was appropriately qualified.
The test procedure
was
acceptable.
H1.2.2
TS Nonthl
Surveillances
a.
Ins ection
Sco
e
61726
The inspectors
observed
operators
perform portions of Procedure
STP I-10, Revision 26,
"Routine Monthly Checks
Required
by Licenses."
Procedure
STP I-1D is utilized by the licensee
to satisfy various
surveillances
required
by plant TS, including system alignment
verifications
and instrument
channel
checks.
The inspectors
also
reviewed previous records of the performance of Procedure
STP I-lD.
b.
Observations
and Findin
s
The inspectors
reviewed the licensee's
documentation
of the performance
of Procedure
STP I-1D for Unit 2 in January
1996.
Channel
checks of the
Loop
1 hot leg and cold leg temperature
indications at the dedicated
shutdown
panel
were not performed.
A design
change
had
been
implemented
which changed
the temperature
elements
Loop
1 from those
specified
by Procedure
STP I-10.
The operator
noted this discrepancy
in
the remarks section of the procedure checklist without performing
a
channel
check
on the
Loop
1 hot leg and cold leg temperatures
(from
TE-414C
and TE-411B respectively).
Several
levels of review failed to
identify this
as
Following the
inspectors'dentification
of this missed surveillance,
the licensee
reviewed
additional
documentation
and found that these
channel
checks
were
successfully
performed in December
1995
and February
1996.
As
a result
-10-
of the inspectors'indings,
the licensee
revised
Procedure
STP I-D to
reflect the appropriate
sensor
inputs to be checked for RCS
Loop
1 hot
and cold leg temperatures.
The inspectors
noted that the design
change
had
been
implemented
in July 1995.
Steps 3.e.
and 3.h. of Attachment
11. 1 to Procedure
STP I-1D directed
the operator to verify the status of Valves
FCV-360 and 366,
the
component cooling water
B and header
A return valves
from
the containment
fan cooler units
(CFCUs).
However,
the valves
were
identified in the control
room to be abandoned
in place.
The
CO
explained that
a design
change
had
been
implemented
rendering
them
and leaving the valves fully open.
Surveillance
Engineering
personnel
explained that these
valves were
abandoned
in place with air
isolated to the valve actuator
in September
1992 (air inlet valves
closed
and sealed)
and that it was unnecessary
to periodically verify
their position.
The licensee
indicated that the procedure
would be
revised to delete
the requirement
to verify the position of these
valves.
During the CO's channel
check of the
RCS subcooled
margin monitor
(SCMM), the
Loop
1 hot leg temperature
input to the
SCMM indicated
approximately 25'F less
than the hot leg temperature
inputs from Loops
2, 3,
and 4.
The problem was not documented
and the inspectors
questioned
the
CO on its acceptabil'ity.
The
CO rechecked
the parameter
reading
and concurred with the inspectors'bservation.
The
CO
subsequently
initiated
an
AR to investigate
the discrepancy
with the
Loop
1 temperature
input.
The low Loop
1 hot leg temperature
input did
not impact the operability of the
SCMM.
Valid temperatures
from several
and from the other three
loops provided adequate
inputs to the instrument for determining
subcooled
margin.
The inspectors
also observed
an
NO perform those portions of
Procedure
STP I-1D associated
with comparisons
of control
room
instrument readings with the indications at the dedicated
shutdown
panel.
The
NO did not have
a control
room reading for cold-calibrated
pressurizer
level (not
a
TS required instrument).
The inspectors
inquired about
how a channel
check
was accomplished
The inspectors
discussed
that
an alternate
indication of this parameter
was available
in the control
room of which the
NO was unaware.
The inspectors
raised
a concern for the channel
check of the instrument to the shift foreman
(SFM)
and the shift technical
advisor.
The
SFM and shift technical
"advisor concurred with the inspectors'onclusion
and
a valid channel
check was subsequently
performed.
Conclusions
Both an inadequate
procedure
and
an ineffective review of the
surveillance,
resulted
in an improperly performed surveillance of the
RCS hot leg
and cold leg temperature
indications at the dedicated
-11-
shutdown
panel
in January
1996.
This is
a violation of TS 6.8. 1
(VIO 50-323/96006-03).
Hl.2.3
AFW Pum
Full Flow Test
a.
Ins ection
Sco
e
61726
The inspectors
observed
routine full flow testing of the turbine-driven
AFW pump
on March 18.
The inspectors
observed
the use of portions of
the following procedures:
STP P-AFW-ll, Rev.
1A, "Routine Surveillance
Test of
Turbine-Driven
AFW Pump 1-1"
AD13.DC2, Rev.
OA, "Dealing With Gauge Oscillations During the
Performance
of Tests
on Safety Related
Pumps"
b.
Observations
and Findin
s
The
AFW pump testing
was accomplished
in accordance
with the licensee's
requirement
to perform full flow testing following each
Mode
3 entry.
The inspectors
observe'd
the pretest tailboard
and portions of the
pretest
system alignment verification.
During the
AFW pump test,
the" inspectors
noted
a steam leak on the
turbine cross-over line.
The licensee
had previously identified the
leak and
had written an
AR to document
and evaluate
the impact of the
deficiency
on operability.
Although the steam leak did not appear to
impact current operability, it should
be monitored
and evaluated
during
periodic
pump surveillance testing.
Adjustment of the governor
was
needed
to achieve
the
AFW pump differential pressure
specified
by the
procedure.
c.
Conclusions
The testing verified that the turbine-driven
The
operators
demonstrated
adequate
system
knowledge during the performance
of the test.
Hl.2.4
Main Feedwater
Valve Testin
a.
Ins ection
Sco
e
61726
The inspectors
observed
the exercising of main feedwater regulating
and
bypass
and isolation valves performed in accordance
with the following
procedures:
~
STP V-3P1,
Rev.
13, "Exercising Hain Feedwater Regulating'alves
and
Bypass
Valves"
-12-
~
STP V-3P2,
Rev.
7, "Exercising Main Feedwater
Isolation Valves
FCV-438,
439,
440 and 441"
b.
Observations
and Findin
s
The inspectors
noted that the testing
was well controlled
and
coordinated.
Operators
involved with the testing
were knowledgeable of
the testing requirements.
The procedure
did not provide for restoration
of the monitor light test switch,
thus leaving the switch in the test
position at the
end of the surveillance.
The inspectors
questioned this
and the
SFM directed the operators
to document
the problem
so that the
procedure
could
be revised prior to future performance.
c.
Conclusions
Operators
were knowledgeable of test requirements
and performed the
testing in accordance
with TS requirements.
The
SFM appropriately
dispositioned
an error in the procedure,
III. En ineerin
El
Conduct of Engineering
fl.l
Rod Dro
Testin
Unit
1
a.
Ins ection
Sco
e
37551
8
71707
On March 16, during the Unit
1
178 outage,
the licensee
conducted
control rod drop testing'n
response
to
"Control
Rod
Insertion Problems."
The inspectors
reviewed
STP R-1B, Revision
15,
"Rod Drop Measurement,"
and
observed
portions of the test,
and reviewed the test results.
b.
Observations
and Findin
s
Interactions
between
the system engineer
and the
CO were both formal
and
clear.
During rod withdrawal, the
CO remained
focused
on power
indications.
During the test,
the control console startup rate
(SUR)
meter for source
range
instrument
NI-32 stuck
on its bottom peg
on
several
occasions.
This required the
CO to tap
on the meter face to
restore
free movement of the meter
and was
a distraction to the
CO.
The
CO appropriately
stopped
rod withdrawal
each
time to correct the
problem.
The operators
did not consider
the
SUR meter to be inoperable.
The inspectors
agreed with their assessment.
Following the rod drop testing,
an
AR (A0396189)
was initiated to
investigate
and repair the
SUR meter.
Historical
ARs revealed that
-13-
0
similar problems
were observed with this meter in November
1995
(A0386028).
The corrective action taken in response
to A0386028 was the
replacement
of the meter housing.
A similar problem was also noted in
NRC Inspection
Report 95-16 where
an intermediate
range meter
was found
to be sticking during
a reactor startup.
The licensee
has incorporated
the repair of the
SUR meter into the scope of the next Unit
1 refueling
outage
scheduled
for Hay 1997.
The nuclear instrumentation
system
engineer
pointed out that the
SUR meter received limited use
and that it
provides
no protective trip, permissive or interlock signals.
The review of the test data indicated that all control assemblies
fully
inserted
into the core within the 2.7 seconds
required
by TS.
Comparison with the data
and traces
obtained
from previous testing
indicated that there
were
no significant changes
in rod drop responses.
The average
rod drop time was 1.38 seconds
during the testing
performed
during the
1T8 outage
and 1.39 seconds
from the testing
performed during
the last Unit
1 refueling outage,
1R7.
c.
Conclusions
The rod drop testing
was well controlled
and in accordance
with the
licensee's
surveillance
procedure.
Test results
indicated that rod drop
times
had not significantly changed
since
1R7,
Although the control console
SUR meters
provide
no protective trip,
interlock or permissive signals,
they are relied
upon
by operators
to
provide accurate
indication of reactivity changes
in the nuclear
source
range.
Their continued reliability is essential
for the safe conduct of
evolutions involving positive reactivity .additions
such
as the approach
to criticality.
The licensee's
actions to correct the identified
problems with the
SUR meters will be tracked
as Inspection
Followup Item
(IFI 50-275/96006-04).
E2
Engineering
Support of Facilities
and
Equipment
E2. 1
Diesel
Generator
Low Tem erature
Alarm
a.
Ins ection
Sco
e
37551
On April 10, the licensee
declared
EDG 2-1 inoperable
based
upon low
lube oil temperature.
The inspectors
reviewed the event with the
on-shift operators
and discussed
the lube oil temperature
requirements
with
EDG system engineer.
The inspectors
also reviewed the licensee's
corrective actions
in response
to
NRC Violation 50-275/95014-01.
b.
Observations
and Findin
s
On April 10, the licensee
was performing scheduled
maintenance
on
EDG 2-3 and its associated
4kV and
480V vital. buses.
The clearance
of
these
buses
resulted
in an expected
loss of power to the 'B'ontactor
panel for
EOG 2-1.
The '8'ontactor
panel
provides
power to the
The lube oil heaters
are designed
to maintain
diesel
lube oil temperature
between
90-120'F.
The loss of power to the
heaters
caused
lube oil temperature
to fall below 90'F.
This condition
was identified by the turbine building auxiliary operator during shift
rounds.
The immediate corrective action taken
by the licensee
was to
operate
EDG 2-1 to raise
lube oil temperature.
The licensee
subsequently
installed
a temporary jumper to provide power to the lube
oil heaters
while maintenance
continued
on
EDG 2-3 and its associated
buses.
during this event; therefore,
operability
of
EOG 2-1
was not required
by TS.
The on-shift operators
staied that
a low lube oil temperature
alarm was
not received
in the control
room.
Further inquiry revealed that the
low lube oil temperature
alarm setpoint for each of the diesels
was less
than
90oF
NRC Inspection
Report 50-275/95014
documented
a violation For failure to
test the
EDGs at ambient conditions
as required
by TS.
In response
to
the violation, the licensee
revised
the governing
STP to require initial
jacket water
and lube oil temperatures
to be between
90-120
F.
Prior to
this, the operability threshold for lube oil temperature
was 70'F.
The
licensee's
reply to the Notice of Violation, dated
November 27,
1995,
and associated
NCR did not address
raising the lube oil low temperature
alarm setpoints.
Conclusions
Licensee
actions to restore operability of
EOG 2-1 were prompt
and
effective.
The failure to adjust the low temperature
setpoint for the
alarm when the lube oil temperature
for
operability was increased
from 70'F to 90'F was considered
to be
a
weakness.
Core Offload Practices
and
S ent Fuel
Pool Controls
Ins ection
Sco
e
92903
The inspectors
reviewed the licensee's
procedures
and past practices for
core offload during refueling outages.
The inspectors
reviewed the
following documents:
Diablo Canyon
Decay Heat Management
Practices
During Refueling Outages
USNRC Standard
Review Plan,
Section
9. 1.3,
"Spent
Fuel
Pool Cooling and Cleanup
Systems"
Diablo Canyon
TS
-15-
~
Diablo Canyon License
Amendment
(LA) 22/21
(Expansion of Spent
Fuel
Pool Storage
Capacity Units
1
and 2)
and the associated
Safety Evaluation Report
(SER)
b.
Observations
and Findin
s
UFSAR, Section
9. 1.4.2.3,
describes
a one-third core offload.
However,
the licensee
has
conducted
a full-core offload during each refueling
outage
since the start of commercial
operation of the units.
Further,
a
safety evaluation
has not been
performed,
as required
by
prior to the licensee's
departure
from performing core offloads
as
described
in the
The
SER,
which approved
LA 22 and
21 for Units
1 and
2 respectively,
concluded,
in part, that the spent fuel pool temperature
would not
exceed
140
F for normal offload conditions (i.e., unloading of
76 assemblies)
and
212
F for abnormal offload conditions (i.e.,
full-core offload).
The licensee's
thermal-hydraulic analysis
supported
these
conclusions
and demonstrated
that the spent fuel pool temperature
would not exceed
140'F during
a one-third core offload and
175'F for a
full-core offload.
The inspectors
questioned
whether the 140'F temperature limit should
apply as the licensing basis for full-core offloads since they had
become
the routine, or normal
method of refueling.
The licensee
concluded that the
140
F temperature limit was applicable to full-core
offloads.
The licensee
had not previously implemented controls to
ensure
the spent fuel pool temperature
would not exceed
140'F following
full-core offloads.
Further investigation
by the licensee,
after being
questioned
by the inspectors,
revealed
other inconsistencies
with
temperatures
used in analyses
and associated
controls.
The
inconsistencies
are described
below:
~
The criticality analysis of record
assumed
a maximum normal
temperature
of the spent fuel pool of 150'F;
however,
the
Equipment Control Guideline allowed
up to 175'F.
The licensee
noted
on April 2,
1996, that the Unit 2 spent fuel
pool temperature
decreased
to 66
F which was below the 68
F
minimum temperature
assumed
in the criticality analysis.
The
licensee initiated actions to reduce
CCW flow which had little
impact on the spent fuel pool temperature.
Subsequently,
the
licensee
performed
a criticality analysis that demonstrated
that
the reactivity in the spent fuel pool would be below the
regulatory limit for a pool temperature
as low as 32'F.
Section
9. 1.3. 1 of the
UFSAR notes that the spent fuel pool cooling
analysis
is based
upon
a full-core offload completed
in no less
than
148 hours0.00171 days <br />0.0411 hours <br />2.44709e-4 weeks <br />5.6314e-5 months <br /> following shutdown.
During the
2R6 refueling outage
a
-16-
full-core offload had
been
completed
146 hours0.00169 days <br />0.0406 hours <br />2.414021e-4 weeks <br />5.5553e-5 months <br /> after shutdown.
The
licensee's
refueling procedures
did not incorporate controls to ensure
that core offload would not be completed
in less
than the
148 hours0.00171 days <br />0.0411 hours <br />2.44709e-4 weeks <br />5.6314e-5 months <br />.
The licensee's
disposition of Information Notice
( IN) 95-54 by the
independent
safety evaluation
group
(ISEG) did not identify any problems
with the processes
or activities related to decay heat
management.
The
ISEG review noted that "core offload practices
and thermal
design
limitations are well documented
and conservative
such that actual
operating practices
are
bounded
and considered
adequate."
The failure
of ISEG to identify problems
associated
with the licensee's
decay heat
management
practices
during refueling outages
was
a missed opportunity
to identify and correct these
problems.
The licensee
implemented corrective actions for the
above deficiencies
prior to the Unit 2 refueling outage
(2R7).
The corrective actions
included:
performing
a
10 CFR 50.59 safety evaluation for the normal conduct
of a full-core offload,
establishing
administrative controls to ensure
spent fuel pool
temperature
is maintained within the licensing basis
and the
assumptions
of the supporting
analyses,
establishing
administrative controls to ensure that the core is
not offloaded at
a rate faster than that
assumed
in the supporting
thermal-hydraulic analysis,
and
revising the
UFSAR description of the refueling procedure.
c.
Conclusions
The licensee's
failure to perform
a safety evaluation prior to
performing full-core offload is an unresolved
item pending
NRC review
(URI 50-275,323/96006-05).
This caused
the licensee's
failure to
implement administrative controls for the reload process
(spent fuel
pool temperature
and time for full-core offload).
E4
Engineering Staff Knowledge
and Performance
E4.1
Review of Desi
n Chan
e Packa
e
J-050216
a.
Ins ection
Sco
e
37551
The inspectors
reviewed
DCP J-050216,
including the safety evaluation,
technical description
and drawings,
and the proposed
change
to the
This
DCP replaced
the input to Loop 2-1 reactor coolant
system
cold leg wide range
TE (TE-413B) with an alternate
available
sensor
(TE-411B) in order to provide the
TS required indication at the
dedicated
shutdown
panel
in Unit 2.
The inspectors
discussed
the
-17-
4
changes
with the licensee's
staff and walked
down the dedicated
shutdown
panels
in both units.
b.
Observations
and Findin
s
0
The change
was
implemented
in July 1995
as
an "install and remove"
change. 'he
DCP indicated that the configuration would be restored
during the "next suitable" Unit 2 outage.
The next Unit 2 refueling
outage
was scheduled
for April 1996.
The
DCP included
a proposed
UFSAR change
which was submitted to the
licensee's
licensing organization.
The proposed
UFSAR change
inappropriately included
a change to Table 9.5G-2,
page
10, which was
for Unit
1 only.
Some sections of the Fire Hazards Analysis (including some not affected
by the
UFSAR change for this
DCP) failed to identify with which unit the
various
components
were associated.
An example of an unclear section
was Fire Area TB-7, Fire Zone
19-A (beginning
on page 9.5A-561).
The
DCP included extensive
documentation
of the implications of the
change.
The inspectors
noted that the
DCP package
did not explicitly
state
in the first seve'ral
pages
whioh unit was affected
by the change.
However, consistent with licensee practice,
the
DCP had
an even
number,
which implied that the change
was for Unit 2.
c.
Conclusions
The
DCP was thorough in addressing
most aspects
of the change with some
minor discrepancies
noted.
Weaknesses
in the completeness
of
engineering
work were evident.
E7
equality Assurance
In Engineering Activities
f7. 1
Review of LAs and Their
Im act
on the
a.
Ins ection
Sco
e
37551
The inspectors
reviewed
a sample of 6 approved
LAs to determine their
impact, if any,
on the facility UFSAR.
Specifically, the inspectors
reviewed the applicable portions of the
UFSAR to evaluate
the
consistency
and accuracy of the
UFSAR with the approved
changes
in the
LAs.
b.
Observations
and Findin
s
The inspectors
reviewed
LAs 94 and
93 for Units
1
and 2, respectively.
These
amendments
revised
the
TS requirements
for remote
shutdown
instrumentation
to be consistent
with the Westinghouse
Standardized
TSs
(NUREG 1431).
The licensee
concluded that indication of the
RCS hot and
4
'I
C I ~
gl
~
-18-
cold leg temperatures
was required for remote
shutdown of the plant.
The licensee
also concl,uded that indication of emergency
boration flow
was not required for remote
shutdown.
Although the revised
TS reflected
these
conclusions,
the licensee's
UFSAR did not.
Specifically,
Section
7.4, 1. 1 of the
UFSAR listed emergency
boration flow as
a
required indication for shutdown of the plant outside the control
room
while it remained silent
on the requirement for RCS temperature
indication.
The inspectors
reviewed
LAs 89 and 88.
These
amendments
revised the
TS
to reduce
the minimum required
CCW flow to each of the
CFCUs from
2000
gpm to 1650
gpm during normal operation.
The licensee's
post-loss
of coolant accident
containment
performance
analysis
in the
assumes
a design basis
CCW flow of 2000
gpm to at least
two of the
CFCUs.
The licensee's
safety analysis
accompanying
the
LA request
justified the difference
between
the minimum
CCW flow in TS and the
design
basis
CCW flow in the
UFSAR analysis
based
upon the automatic
isolation of the nonvital
in response
to
a loss of coolant
accident.
The isolation of the nonvital header
under accident
conditions
would redirect sufficient flow to the vital
to
provide
a minimum of 2000
gpm to the
CFCUs.
Although the
UFSAR had
been revised
by the licensee
to reflect these
LAs, the revisions
were incomplete
and,
as
'a result,
the
UFSAR was both
inconsistent with the
LA and internally inconsistent.
Specifically,
Section 9.2.2.2.7 of the
UFSAR states
that during normal operations,
flow through the fan coolers is throttled to pass
the design basis
accident
flows. It further states
that full flow is assured
through
each
CFCU under accident conditions without any automatic or operator
action.
This contradicts
the
LA safety analysis
which assumed
normal
flow rates
less
than the
2000
gpm design basis
and required the
automatic isolation of the nonvital
to achieve full flow
through the
CFCUs,
In addition,
both Section
9.2 '.2.7
and Table 6.2-26
of the
UFSAR define normal
CCW flow through the
CFCUs
as
2000
gpm while
Table 9.2-5 defines
normal
CCW flofv to all of the
CFCUs
as 8,250
gpm
(1650
gpm per unit).
The table incorporated
into Section 9.2.2.2.7 of the
UFSAR stated that
the design
CCW inlet temperature
for the
CFCUs during normal operati ;
was 95'F.
In contrast,
Table 6.2-26 of the
UFSAR lists the design inlet
temperature
during normal operation
as 90'F.
The licensee failed to revise Section 8.3.1.1.9 of the
UFSAR from 3.6kV
to 3.8kV when implementing the increase
in setpoint of the secondary
relay to 3785
VAC authorized
by LA 85/86.
In addition, the
licensee failed to revise the
4kV bus nominal voltages listed in
Appendix 8.3A after raising the secondary
relay setting.
The inspectors
determined
that. the licensee
had also recently noted
these deficiencies
during
a
UFSAR review.
-19-
The licensee
has
issued
an
NCR to address
the
UFSAR inaccuracies
'and,
as
a part of the corrective actions,
the licensee initiated
a review by
system engineers
of the entire
The initial review efforts were
done to gain
a quick assessment
of the
UFSAR's accuracy.
I.
Conclusions
The deficiencies identified in the
UFSAR are continuing to be evaluated.
However,
the number of deficiencies
in the relatively small
sample is
indicative of weaknesses
in this program to review and update
the
in response
to LAs and therefore
is of regulatory concern.
These
deficiencies,
the examples
discussed
in Section 02. 1,
and those
being
identified by the licensee
in their
UFSAR review process
are being
tracked
as
an unresolved
item (URI 50-275/96006-06)
pending further
NRC
review.
f8
Miscellaneous
Engineering
Issues
E8. 1
Review of UFSAR Commitments
A recent discovery of a licensee
operating their facility in
a manner
contrary to the
UFSAR description highlighted the need for a special
focused
review that compares
plant practices,
procedures,
and/or
parameters
to the
UFSAR description.
During the inspection period, the
inspectors
reviewed the applicable sections of the
UFSAR related to the
inspection
areas
discussed
in this report.
The following
inconsistencies
were noted
between
the wording of the
UFSAR and the
plant practices,
procedures,
and/or parameters
observed
by the
inspectors.
The deficiencies
are discussed
in the sections
in the
report that are referenced
below:
02. 1
UFSAR inconsistency with referenced
charcoal
bed methyl
iodide removal efficiency
E2.2
Core offload practices
did not coincide with actual
licensee
practice
E4. I
Inaccuracies
in UFSAR revision written for DCP J-050216
E7. 1
incomplete
UFSAR revisions written for LAs (several
examples
noted)
I
V. Hang ement Neetin
s
Xl
Exit meeting
Summary
The inspectors, presented
the inspection results to members of the licensee
management
at the conclusion of the inspection
on April 18,
1996.
The
licensee
acknowledged
the findings presented.
0
-20-
The inspectors
asked
the licensee
whether
any materials
examined during the
inspection
should
be considered
proprietary.
No proprietary information was
identified.
-21-
PARTIAL LIST OF
PERSONS
CONTACTED
Licensee
J.
R.
D.
H.
E.
S.
G.
T. L.
C.
D.
R.
L.
D.
B.
R.
P.
NRC
Becker, Director, Operations
Behnke,
Senior Engineer,
Regulatory Services
Chaloupka,
Engineer,
Surveillance
Engineering
Chestnut,
Senior Engineer,
Primary Systems
Engineering
Grebel, Director, Regulatory Services
Harbor,
Engineer,
Regulatory Services
Johnson,
Supervisor,'egulatory
Services
Miklush, Manager,
Enineering Services
Powers,
Manager,
Operations
M.
D. Tschiltz, Senior Resident
Inspector
S.
AD Boynton,
Resident
Inspector
J.
A. Sloan,
Senior Resident
Inspector,
San Onofre Nuclear Generating
Station
-22-
IP 37551:
IP 61726:
IP 62703:
IP 71707:
IP 71750:
IP 92700:
IP 92903:
INSPECTION
PROCEDURES
USED
Onsite Engineering
Surveillance
Observations
Maintenance
Observations
Plant Operations
Plant Support Activities
Followup - Operations
Followup
Engineering
ITEMS OPENED,
CLOSED,
AND DISCUSSED
~0en ed
50-275/96006-01
failure to follow Operations
Procedures
OP L-3 and L-4
50-275/96006-02
failure to follow Administrative Procedure
AD2. ID1
50-275/96006-03
failure to perform channel
check of remote
shutdown
instrument
50-275/96006-04
IFI
50-323/96006-05
licensee
long-term corrective actions to improve
source
range
instrument reliability
failure to perform
a
10 CFR 50.59 evaluation for full-
core offload
50-275/96006-06
50-323/96006-06
failure to adequately
review and update
the
Closed
50-275/95016-01
Discussed
failure to follow procedure
during vessel
draindown;
failure to follow procedure for source
range
operational
checks
50-275/94028-01
failure to follow EDG test procedure
LIST OF
ACRONYHS USED
1R7
1TS
AFD
CFCU
CO
ISEG
LA
NI
NO
OP
POA
SCHH
SFM
SUR
TS
Unit
1 Seventh
Refueling Outage
Unit 1, Cycle 8, Transformer
Outage
Axial Flux Distribution
action request
component cooling water
containment
fan cooler unit
control operator
control
room ventilation system
chemical
and volume control
system
design criteria memorandum
design
change
package
emergency diesel
generator
flow control valve
Independent
Safety Evaluation
Group
license
amendment
maintenance
procedure
nonconformance
report
nuclear instrument
nuclear operator
operating
procedure
prompt operability assessment
system
subcooled
margin monitor
Safety Evaluation Report
shift foreman
surveillance test procedure
start-up rate
temperature
element
Technical Specification
Updated Final Safety Analysis Report
work order