ML17304B438
| ML17304B438 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 08/24/1989 |
| From: | Richards S NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | |
| Shared Package | |
| ML17304B434 | List: |
| References | |
| 50-528-89-30, 50-529-89-30, 50-530-89-30, NUDOCS 8909130134 | |
| Download: ML17304B438 (37) | |
See also: IR 05000528/1989030
Text
U. S.
NUCLEAR REGULATORY COMMISSION
REGION
V
Re ort Nos.
Docket Nos.
License
Nos.
50-528/89-30,
50-529/89-30
and 50-530/89-30
50-528$
50-529,
50-530
=
Licensee:
. Arizona Nuclear
Power Project
P. 0.
Box 52034
Phoenix,
AZ. 85072-2034
E
P1
Y
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l
i
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i
1,
53
Ins ection Conducted:
June
12 through August 6,
1989
Inspectors:
Approved By:
T. Polich, Senior Resident
Inspector
D. Coe, Resident
Inspector
C. Myers, Resident Inspector,
Rancho
Seco
P. squalls,
Resident
Inspector,
Rancho
Seco
ic ar s,
ie
Reactor Projects
Section II
e-29-89
a
e
igne
Ins ection
Summar
Ins ection
on June
12 throu
h Au ust
6
1989.
Re ort Nos. 50-528/89-30,
5-
an
-5
-3
Areas
Ins ected:
Routine, onsite,
regular
and backshift inspection
by
t e two resi ent inspectors,
and two Regional
inspectors.
Areas
inspected
included: previously identified items; review of plant
activities; engineered
safety feature
system walkdowns; monthly
surveillance testing; monthly plant maintenance;
review of licensee
contractor qualifications - Units 1, 2, and 3; restart - Unit 2; missed
procedure
step while flashing generator field - Unit 2; forced outage
due
to pipe break - Unit 2; reactor trip and safety injection - Unit 2; main
feedwater suction piping overpressurization
- Unit 2; load rejection from
100% power - Unit 2; improper maintenance
on atmospheric
dump valve
nitrogen supply reducing regulator valves
(ADV regulator valves)-
Unit 2; integrated
safeguards
surveillance testing - Unit 3; review of
licensee
event reports - Units 1,
2 and 3;
and review of periodic
and
special
reports - Units 1,
2 and 3.
During this inspection the following Inspection
Procedures
were utilized:
40500,
61701,
61726,
62703,
64704,
71707,
71710,
92700 and 93702.
8g09i30184
8~r082g
ADOCK 0 '000528
9
Safet
Issues
Mana ement
S stem
SINS) Items:
None
Results:
Of the nine areas
inspected,
two violations were identified.
One violation pertained to failure to control work on safety-related
equipment with an approved work order.
The second violation pertains to
fire 'protection in that flammable liquid lockers
had expired storage
permits.
General
Conclusions
and
S ecific Findin s
Si nificant Safet
Matters:
None
Summar
of'iolations:
Two
Summar'f Deviations:
None
0 en Items
Summar
Two items closed,
and five new
items were opened.
DETAILS
Persons
Contacted:
The below listed technical
and supervisory
personnel
were
among
those contacted:
Arizona Nuclear
Power Pro 'ect
- R. Adney,
J. Allen,
- R. Badsgard,
J. Bailey,
- B. Ballard,
- C. Belford;
- H. Bieling,
P. Brandjes,
C. Churchman,
- W. Conway,
- J. Haynes,
- D. Heinicke,
P.
Hughes,
- W. Ide,
- D. Karner,
J. Kirby,
J. LoCicero,
- W. Marsh,
A. McCabe,
D. Phillips,
J. Reilly,
- A. Rogers,
C. Russo,
- T. Shriver,
G. Sowers,
R. Younger,
- W. guinn,
Plant Manager,
Unit 3
Relief Plant Manager
Supervisor Nuclear Engineering
Department
Assistant Plant Manager, Unit 3
guality Assurance
Director
Supervisor Fire Protection
Emergency Planning/Fire
Department
Manager
Central
Maintenance
Manager
Work Control Manager, Unit 3
Executive Vice President - Nuclear
Vice President,
Nuclear Production/Site Director
Plant Manager, Unit 2
Radiation Protection
5 Chemistry Manager
Plant Manager, Unit I
Vice President - Nuclear
Director, Nuclear Production Support
Independent
Safety Engineering
Manager
Plant Director
Maintenance
Manager, Unit 1
Outage
Management
Manager
Standards
and Technical
Support
Director'icensing
Manager
Assistant
equality Assurance
Director
Compliance
Manager
Engineering Evaluations
Manager
Plant Standards
and Control Manager
Nuclear Safety
and Licensing Director
The inspectors
also talked with other licensee
and contractor
personnel
during the course of the inspection.
- Attended the Exit meeting held with NRC Resident
Inspectors
on August 10, 1989.
Previousl
Identified Items - Units
1
2
and
3
92702,
92701
a. 'losed
Fol 1 owu
Item
529/88-31-01:
"Maintenance
Work Order
Ste
s Not Si ned
f - Unst
The inspector
reviewed the training records
documenting
retraining of maintenance
personnel
in the proper stepwise
signoff technique to be used in performing work under
a
maintenance
work order.
!
C
f
I
(
II
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l
The inspector questioned
several
crafts personnel
and found
them to be aware of the proper signoff techniques.
The inspector
found the licensee's
actions to be adequate.
This item is closed.
b.
Closed
Followu
Item
529/88-42-02
"Dama ed'Batter
Cell"-
nit
This item involved damage to
a battery cell case in the class
1E, "B" battery,
channel
"D," which the licensee
discovered
during surveillance testing.
Upon discovery
on January
16,
1989 the licensee
had initiated a controlled shutdown in
compliance with technical specifications.
A temporary
modification to jumper out the affected cell was installed,
and
the licensee
restored
the battery to service after completing
the surveillance test to demonstrate
the battery operable in
the modified condition.
The inspector
reviewed the licensee's
event investigation
report, Special
Plant Event Evaluation Report
(SPEER)
89-02-002,
dated
February 7, 1989, which identified that the
damage
most probably occurred during dismantling of scaffolding
in the battery
room on January
12,
1989.
The inspector
found the licensee's
evaluation to be thorough in
identifying the cause of the
damage
and establishing corrective
actions to preclude reoccurrence.
This item is closed.
No violations of NRC requirements
or deviations
were identified.
3.
Review of Plant Activities
71707,
71710;
93702)
a
~
Unit 1
b.
Unit
1 remained in a refueling outage status with fuel off"
loaded during the entire reporting period.
Unit 2
Unit 2 began
the inspection period in mode 3.
On June
23,
1989
the licensee
requested
NRC concurrence
to restart Unit 2 after
completing repairs to Steam
Bypass Control Valve 1008.
The
licensee
determined
the Steam
Bypass Control Valve 1008
had
been incorrectly modified in April 1988.
The licensee
subsequently
submitted
a second letter requesting
NRC
concurrence for restart of Unit 2 after modification of valve
1008
and three other Steam
Bypass
Control valves.
The unit was restarted
on June
29,
1989 and paralleled
onto the
grid on June
30,
1989.
On July 4,
1989 at 12:33
am,
MST,
a
power reduction
was initiated due to an unisolable
leak from a Main Feed
Pump
(MFP) suction drain, line (see
paragraph
10).
The reactor
was taken to mode
2 at 3:31
am,
,
MST.
The plant entered
Node
1 on July 6, 1989.
The unit
operated
at
100%%d power until July 12,
1989 when
and safety injection occurred
(see
paragraph
11).
The reactor
was restarted
on July 20,
1989.
The plant operated until
August 4, 1989,
when
a turbine trip occurred.
The plant was
synchronized
to the grid on August 6,
1989 (see
paragraph
12).
c.
Unit 3
Unit 3 remained in a refueling outage status.
The core was
refueled beginning
on July 24, 1989,
when
Mode
6 was
reestablished.
The fuel reload
was completed'on July 31,
1989.
The unit remained in mode
6 until the end of the inspection
period.
d.
Plant Tours
The following plant areas
at Units 1,
2 and
3 were toured
by
the inspectors
during the inspection:
Auxiliary Building
Containment Building
Control
Complex Building
Diesel
Generator Building
Radwaste
Building
Technical
Support Center
Turbine Building
Yard Area and Perimeter
The following areas
were observed
during the tours:
1.
0 eratin
Lo s and Records
Records
were reviewed against
Tec nica
peci ication and administrative control
.procedure
requirements.
2.
Monitorin
Instrumentation
Process
instruments
were
o serve
or corre ation
etween
channels
and for
conformance with Technical Specification requirements.
'3
~
~Ehif
M
i
C
1"
"d lift
i
g
observed for conformance with 10 CFR 50.54.(k), Technical
Specifications,
and administrative
procedures.
The inspectors
observed
licensee
operators
to be attentive
and alert during backshift
and weekend tours.
4.
E ui ment Lineu s
Various valves
and electrical
breakers
were veri ie
to be in the position or condition required
by Technical Specifications
and administrative
procedures
for the applicable plant mode.
This verification included
routine control board indication reviews
and the conduct
of partial
system lineups.
E ui ment Ta
in
Selected
equipment, for which tagging
requests
a
een initiated, were observed
to verify that
tags
were in place
and the equipment
was in the condition
specified.
General
Plant
E ui ment Conditions
Plant equipment
was
o serve
or in scations
o
system leakage,
improper
lubrication, or other conditions that would prevent the
systems
from fulfillingtheir functional requirements.
Fire Protection
Fire fighting equipment
and controls were
f
i hi hi
1SP if'
d
administrative
procedures.
On August 1, 1989, the inspector identified three
flammable storage
lockers with expired flammable storage
permits in Unit l.
One was
on the Auxiliary Building roof
and expired
on March 2, 1989.
,The other two were
on the
120'levation of the Radwaste
Building and the permits
expired
on July 15,
1989.
The storage of combustible/-
flammable materials with expired permits
was identified as
a potential violation of a license condition
(528/89-30-01).
Plant Chemistr
Chemical analysis results
were reviewed
or con ormance with Technical Specifications
and admin-
istrative control procedures.
Securit
Activities observed for conformance with
regu atory requirements,
implementation of the site
security plan,
and administrative
procedures
included
vehicle
and personnel
access,
and protected
and vital area
integrity.
The licensee
reported
two instances
of security guard
inattentiveness
during this inspection period.
The events
will be followed as part of the next routine security
inspection.
Plant Housekee
in
Plant conditions
and
mater>a
equipment storage
were observed to determine the
general
state of cleanliness
and housekeeping.
Housekeeping
in the radiologically controlled areas
was
evaluated with respe'ct to controlling the spread of
surface
and airborne contamination.
Radiation Protection Controls
Areas observed
included
contro
point operation,
records of licensee's
surveys
within the radiological controlled areas,
posting of
radiation
and high radiation areas,
compliance with
Radiation
Exposure
Permits,
personnel
monitoring devices
being properly worn, and personnel frisking practices.
~
~
~
~
The licensee
discovered
several
radioactive
isotopes
[Cobalt-60 (Co-60), Cesium-137
(Cs-137),
(Mn-54) and Antimony-125 (Sb125)j in the Unit 1 and
3
cooling tower sludge
on July 14,
1989.
This sludge
had
been
dumped on-site in the Water Reclamation Facility
landfill in May 1989.
The licensee's
guality Audits and
Monitoring personnel
identified the problem during
a
routine audit.
Regional
health physics
inspectors will
followup on the licensee's
monitoring and disposal of the
sludge.
One violation of an
NRC license condition was identified.
4.
En ineered Safet
Feature
S stem Walkdowns - Units 1,
2 and
3
Selected
engineered
safety feature
systems
(and systems
important to
safety)
were walked
down by the inspector to confirm that the
systems
were aligned in accordance
with plant procedures.
During
the walkdown'of the systems,
items
such
as hangers,
supports,
electrical
cabinets
and cables,
were inspected
to determine that
they were operable,'and
in a condition to perform their required
functions.
Accessible portions of the following systems
were walked
down during this inspection period.
Unit 1
o
Class
lE Batteries
o
Remote
Shutdown
Panel
o
"B" Emergency
Diesel
Generator
Unit 2
o
Class
1E Batteries
o
Remote
Shutdown
Panel
o
System
o
"A" and
"B", Emergency Diesel
Generator
Unit 3
o
Class
1E Batteries
o
"B" Emergency Diesel Generator
During the inspection period, the inspector walked
down the Unit 3
Class
1E batteries.
The inspector
observed that the inter-cell
bus
ties for the "C" battery
had been
removed from 42 of the 60 cells in
the battery.
The inspector inquired into the work in progress
and
found that the "C" battery
had been out of service for approximately
3 weeks
pending resoluti'on of a problem involving proper torque for
the bolted connector for the inter-cell
bus ties to the cell posts.
Licensee representatives
from electrical
maintenance
stated that the
problem was found to exist only on the "C" battery
and not the other
batteries
which were in service.
The inspector found the ongoing
resolution of the problem to be adequate.
No violations of NRC requirements
or deviations
were identified.
5.
Monthl
Surveillance Testin
- Units 1,
2 and
3
61726)
a
~
b.
Selected
surveillance tests
required to be performed
by the
Technical Specifications
(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 performance of the surveillance tests;
3)
the surveillance tests
had
been
performed at the 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
P
d
~D
Radiation Monitoring Monthly Functional
Test
Remote
Shutdown
Panel
System Instrumentation
Calibration
Unit 2
d
Routine Surveillance Daily Midnight Logs
Pump AFA-POl Operability
Test
Unit 3
Procedure
Descri tion
o
Class
1E Diesel
Generator
and Integrated
Safeguards
Surveillance'Test
Train "A".
No violations of NRC requirements
or deviations
were identified.
6.
Monthl
Plant Maintenance
- Units 1,
2 and
3
62703
a
~
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
gA/gC
involvement, proper
use of safety tags,
proper equipment
alignment
and use of jumpers,
personnel
qualifications,
and
proper retesting.
The inspector verified that reportability
for these activities
was correct.
fl
l
I
II
b.
Specifically, the inspector witnessed
portions of the following
maintenance activities:
Unit 1
Descri tion
o
Plant Protective
System
Power Supply Replacement.
o
Emergency Diesel
Generator
"A" Piston/Cylinder
Replacement.
Unit 2
o
Steam
Bypass
Control Valve Tear
Down of 1008.
o
Steam
Bypass
Control Valve Modifications,
o
Atmospheric
Dump Valve Nitrogen Regulator Rebuild.
o
Main Feed
Pump Drain Line Die Penetrant
Test.
o
Replacement
of the Linear Calibrate Switch on Nuclear
Instrument
Channel
"B".
Unit 3
Descri tion
o
Repacking of Shutdown Cooling System Suction Line
Isolation Valve SI-654.
o
Calibration of High Pressure
Safety Injection
Pump
S04E
Agastat
Time Delay Relay.
No violations of NRC requirements
or deviations
were identified.
7.
Review of Licensee Contractor (}ualifications - Uriits
1
2,
and
3
The inspector
reviewed
the qualifications
and background verifi-
cations of two licensee contract
employees
from two different
contractor organizations.
The inspector
assessed
each individual's
reported training and experience
against their a'ssigned
duties.
In
addition, the inspector
assessed
the adequacy of the contractor
documented
background verification check.
Finally, the inspector
spot checked
the validity of the background
checks
by independently
verifying one of each
employee's
most recent
employment positions
which supported
the required qualification level per ANSI/ANS
3.1-1978Property "ANSI code" (as page type) with input value "ANSI/ANS</br></br>3.1-1978" contains invalid characters or is incomplete and therefore can cause unexpected results during a query or annotation process..
8.
The 'inspector
concluded that the training and experience of each
employee
was accurately
represented
on the employee's
resume, that
the stated qualifications were sufficient for the duties assigned
and that the contractor organization
background verification check
was sufficiently detailed to provide assurance
that the
qualifications were acc'urate.
The inspector
had
no further
questions.
No violations of NRC requirements
or deviations -were identified.
Restart - Unit 2
92700
Palo Verde Unit 2 was voluntarily shutdown
on March 15,
1989 after
problems
were identified with the, Unit 1 Atmospheric
Dump Valves
(ADVs).
The
NRC subsequently
issued
a Confirmatory Action Letter
(CAL) on March 28, 1989, which confirmed the course of action the
licensee
would take prior to requesting
NRC concurrence
to restart
any of the Palo Verde units.
The licensee
compiled
a list of all
NRC concerns,
as well as all
concerns identified by their own investigation.
The
NRC review of
licensee
actions
taken in response
to these
concerns
was
documented
in inspection report 50-529/89-21.
On June
23,
1989, the licensee
responded
in writing to the
CAL dated
March 28,
1989.
The licensee
confirmed that the agreed
upon actions,
to restart
Palo Verde Unit 2 were complete with the exception of
work on Steam
Bypass
Control Valve (SBCV) 1008.
The licensee
also
agreed
to provide due dates for the completion of Unit 2 Post
Restart
items within 30 days of Unit 2 restart.
Additionally, the
licensee
indicated that
a Category
3 Investigation regarding
the
vendor interface with maintenance
during the setting of ADV nitrogen
'regulators
was expected
to be complete
by July 10,
1989.
On June 28,
1989, the licensee
sent another letter to the
NRC
explaining the discovery that
SBCV 1008 internals
were not in the
configuration required
by the design.
Specifically, three
wave
springs
were found in the valve rather than the one required.
The
licensee
also indicated that
a formal investigation
was initiated to
determine
the root cause of the extra wave springs.
Additionally,
the letter stated that
SBCV 1008 was restored to its design
configuration
and tested satisfactorily.
The licensee certified
that the Steam
Bypass
Control System
was fully functional.
The
NRC responded
to the licensee
on June
28, 1989, indicating the
licensee
had
NRC concurrence
to restart
Palo Verde Unit 2.
The Palo Verde Unit 2 reactor
was taken critial on June
29,
1989 at
0401
MST.
No violations of NRC requirements
or deviations
were identified.
Missed Procedure
Ste
While Flashin
Generator
Field - Unit 2
On June
29,
1989, at 1800
MST, with'eactor
power at approximately
12K, the Unit 2 Main Turbine tripped.
The secondary
oper'ator
(licensed reactor operator)
was attempting to flash the main
generator field when
he observed
the field ammeter
increase
to
approximately
4000
amps vice the normal
2100 amps, just prior to the
The licensee's initial review determined that the operator
apparently failed to perform
a portion of the step prior to
attempting to flash the generator field.
The operators
performed
the immediate actions for a turbine trip and
no further attempts
were
made to flash the generator field.
The Plant Manager,
who was
in the Control
Room at the time, requested
that the System Engineer
return to the site to trouble shoot the problem and verify that the
higher than normal current observed
did not damage
the control
circuit.
The licensee's
subsequent
investigation indicated the operator
had
missed
a procedure
step
by not minimizing AC and
DC voltage
regulator settings
and observing the proper indicating lights prior
to flashing'he
generator field.
The licensee is continuing the
investigation
and
has
removed the operator
from control
room duties.
The generator
was successfully
placed in service
on June
30,
1989.
The licensee
changed
the investigation to a
Human Performance
Evaluation,
HPES-89-018,
which was not complete at the
end of the
report period.
The inspector will followup on this
HPES
and the
licensee's
HPES backlog in a future inspection
(529/89-30-01).
No violations of NRC requirements
or deviations
were identified.
Forced
Outa
e
Due To Pi
e Break - Unit 2
93702
On July 4, 1989, at 0033
MST, the licensee
began
a power reduction
from 100$ power'ue to
a leak on
a Main Feed
Pump suction pipe drain
line.
The initial leak
was from a one inch line upsteam of valve
FWN-V110, however,
a one inch line upstream of valve CDN-V628 also
started
leaking
and eventually failed.
The unit was taken off the
grid at 0324
MST and the reactor entered
Mode
2 at 0331
MST.
The licensee initiated an incident investigation to determine
the
cause of the piping failures.
The incident investigation
was not
complete at the
end of the inspection period,
however
the licensee
suspects
that the drain valves failed due to high cyclic fatigue
caused
by a feedwater recirculation valve not being fully closed.
Additionally, the licensee initiated Engineering Evaluation Request
EER-89-FW-013,
which was not complete at the
end of the inspection
period.
This item will be followed in a future inspection
(529/89-30-02).
10
The licensee
completed repairs to the piping and dye penetrant
testing of the other valves
on the Main Feed
Pump suction.
The
licensee
increased
power and paralleled
onto the grid on July 20,
1989.
No violations of NRC requirements
or deviations
were identified.
Reactor Tri
and Safet
In ection - Unit 2
93702
and
92700
On July 12,
1989 at 2212
MST, the Unit 2 reactor tripped from 100%
power on low DNBR due to the loss of power to 13.8
KV bus
NAN-S02,
which supplys
the
1B and
2B Reactor
Coolant
Pumps
RCPs).
The
resulting transient
caused
Reactor
Coolant System
RCS) pressure
to
decrease
below the
1837 psig setpoint for the Safety Injection and
Containment Isolation Actuation Signals
(SIAS) and (CIAS).
The
licensee
declared
an Unusual
Event
(UE) at 2223
pressure,
which decreased
to 1823 psig.
The licensee
terminated
the
UE at 2322
MST after the plant was stabilized in mode
3 with two
RCPs running.
The licensee
did not activate the autodialer at the Shift
Supervisor's
discretion
and the wrong number
was dialed to activate
the county wide beeper
system, resulting in a failure to notify
emergency
response
personnel
as required.
Although these
notification methods failed an adequate
number of 'licensee
personnel
and management
responsed
to the event.
The inspector
responded
to the event
and personally
observed that
the unit had
been stabilized in mode 3.
The inspector closely
followed the licensee's
review of the event,
and in particular, the
licensee
engineering organization's efforts to determine
why RCS
pressure
decreased
to the point at which a SIAS occurred.
The
licensee
concluded that the excessive
RCS depressurization
was
caused
by
a combination of an improper Steam
Bypass
Control
System
(SBCS)
response
and excessive
leakage
past the pressurizer
spray
valves.
Through discussions
with licensee
personnel,
the inspector
determined that the spray valves
had
a 2-3 year history of problems
with the calibration of the valve operators.
Repeated
attempts
had
been previously made to correct the problem, apparently without
success.
In discussions
with licensee
managers, it appeared
that
the spray valve issue
had only recently
been brought to the
attention of a management
level high enough to ensure that
a more
comprehensive 'review of the problem would be undertaken.
The
inspector questioned
why this issue
had taken
such
a long period of
time to be addressed
by management
and suggested
that the licensee
thoroughly review the issue to assess
how it had been previously
handled.
The licensee
agreed that such
a review would be useful.
Pending further inspector
review of the adequacy of the licensee's
previous corrective actions for the spray valve, this was identified
as unresolved
Item 89-30-05.
Regarding
the
SBCS, the licensee
determined that the "Ouick Open"
controllers
had
been calibrated with data that had been superseded.
This resulted in the bypass
valves being open longer than
anticipated,
thereby resulting in an excessive
cooldown of the
RCS.
The loss of power to bus
NAN-S02 was
caused
by a failed potential
transformer fuse.
The licensee
was unable to determine
why the fuse
opened,
and returned
the fuse to the manufacturer for evaluation.
The inspector
reviewed the actions
taken
by the licensee to
determine whether the fuse
had
opened
due to
a valid circuit fault
and considered
the licensee's
actions appropriate.
As discussed
in
Licensee
Event Report
(LER) 50-529/89-009,
the licensee's
review of
the event is continuing.
The
LER will be supplemented
with the
results of this review.
The licensee
restarted
the unit on July 21, 1989, after the
immediate restart
concerns
were addressed.
No violations of NRC requirements
or deviations
were identified.
12.
Main Feedwater
Pum
Suction
Pi in
Over ressurization
- Unit 2
On July 21,
1989, during restart of Unit 2 following a reactor trip
on July 12, the licensee
discovered all six of the main feedwater
pump
(MFP) suction pressure
switches
deformed
due to
overpressurization.
The licensee
evaluated
the cause
and
consequences
of the overpressurization
and determined that it'did
not offset continuation of power escalation.
The licensee
determined that the piping was overpressurized
when
a
recirculation valve was opened, .thereby connecting
the
pump suction
and discharge
piping.
This allowed the
MFP suction piping to be
pressurized
by the
AFM system
due to a leaking check valve.
The inspector
reviewed the event
and the licensee's
resolution of
the problem as part of the lice'nsee's
post trip review.
Based
on
interviews with licensee
personnel
involved in the event,
the
inspector
determined
the following to be
an approximate
time line
for the event.
1989:
7/12
2200 Reactor Trip due to potential transformer
fuse
failure.
7/13
0100 Operations
started
the non-safety related auxiliary
pump (AFN-POl).
0800 Post trip walkdown by systems
engineers
and
operations identified unexpected
cooldown of 7A
heater outlet from 350 degrees
F to 140
de'grees
F.
Also cooldown
was noted affecting leakage
flow through the economizer control valve to the
No.
1000 Operations initiated Long Path Recirculation
(LPR) of
main feedwater inorder to cooldown the feedwater
heaters,
12
7/14
7/19
Operator noted difficulty'in opening
HFP bypass
valve V-13 due to high differential pressure.
(Apparently,
due to pressurization
of the down-
stream piping caused
by the leaking check valve
V-431).
1530
A MFP low pressure trip alarm.
(Apparently due to
failure of the pressure
sensor
due to over
pressurization
of the
HFP suction piping).
1930
B MFP low pressure trip alarm.
Operations
opened
V-46 to initiate LPR in support of
testing to determine
leakage
past
V-431
MFP alarms
were noted
by Operations
and Systems
Engineers
but no work order was written to
investigate
the problem.
V-431 seat
leakage
was repaired.
h'ork Order to investigate
MFP pressure
switch problem
was.written
when alarms
were again, noted during
startup preparations.
7/20
Reactor startup
commenced.
7/21 0030 Reactor Critical.
Six MFP pressure
switches
were replaced
when found to
be unable to calibrate in place.
0700 Pressure
switch was disassembled
in
18C shop
and
found deformed
due to,overpressure.
EER-89-CD-029 initiated.
0840 Hain generator
was synchronized to grid.
0900 Management
informed of concern for
overpressurization.
(Rx power
13K).
o
Calculation to evaluate
consequences
were
initiated.
1200
INC destructively evaluated
a new pressure
switch to
confirm failure mode
due to overpressure
at 1200 psi.
(Rx power 18K)
1330 Onsite engineering
concluded piping stresses
were
acceptable.
1400 Management decision
made to continue
power
escalation.
13
1700 Corporate
engineering
concurred with acceptable
stress
analysis results
EER-89-CD-029 dispositioned.
Based
on
a review of this time line, the inspector
observed
several
weaknesses
in the licensee's
approach
to resolution of this problem.
The licensee's
post trip review did not identify the abnormally
pressurized
feedwater piping due to the recognized
leakage.
Neither did it identify the overpressure
condition
resulting from initiation of LPR.
The post trip review did
address
the leakage
past
V-431 to ensure that it was repaired
prior to startup.
However, the inspector
found that the review
did not formally evaluate
the potential for pressurization
of
the feedwater piping as
a consequence
of the leakage.
As
a
result, the abnormally pressurized
condition of the feedwater
piping was not recognized
or evaluated prior to initiating LPR
to cooldown the feedwater heaters.
Although the operator
noted
unusual difficulty in opening
V-13 to initiate
LPR indicating
an unexpected
high differential pressure
across
the valve, the
potential for,overpressurizing
the
NFP suction piping was not
recognized.
2.
Due to inadequate
communications
between Operations
and Systems
Engineers,
a work order to investigate
and repair the
unexpected
NFP low pressure
alarms
was not initiated in a
timely fashion
when the condition was noted
on July 13, 1989.
The inspector
found that the delay in initiating corrective
actions until July 19,
1989,
appeared
to contribute to the
hurried review and disposition which resulted during startup.
3.
The management
decision to continue
power escalation
appeared
to have
been
based
on an informal resolution of the
consequences
of the overpressurization.
The initial bounding
calculations
and reviews appeared
to have. been
performed in a
hurried and informal manner with questionable
conservatism.
The review was not documented
and checked,
but rather
consensus
was obtained
from various engineering
organizations
over the
phone.
Walkdowns of the affected portions of the systems
were
done without procedures
or written guidance.
In resolving this problem involving non-safety related
equipment,
the inspector
found that the licensee
exhibited
a considerable
relaxation
from the rigor and formality exercised
in the control of
safety related
systems
and equipment.
Although the post trip review
addressed
all identified problems resulting from the trip, the
inspector
found the licensee's
resolution to be less
thorough in
dealing with non-safety related
problems.
The inspector considered
that this lack of a consistent
methodology
appeared
to be
a weakness
in the conduct of the licensee's
post trip review.
With the assistance
of technical
personnel
from the
NRC Office of
Nuclear Reactor Regulation
(NRR), the inspectors .reviewed in some
detail
the. licensee's
engineering
analysis of the effect of the
overpressure
condition
on the
MFW pipe.
The associated
pipe has
a
design
pressure
of 500 psia.
The licensee
analyzed
the pipe for an
overpressure
condition of approximately
1580 psia.
Initially the
licensee
assumed
that the weakest
component of the system
was the
large bore pipe.
The licensee
therefore
analyzed
the pipe, 'assuming
that if the pipe were found acceptable, it would bound all other
components.
The inspector
strongly questioned this assumption,
and
based
on prompting from the
NRC, the licensee
reviewed other
components.
The licensee
then determined that several
30 inch
were actually the limiting components,
and that these
may have exceeded
the minimum yield strength.
The licensee
concluded that the flanges
were acceptable for continued
use
based
in part
on hardness
testing,
magnetic particle testing,
and visual
inspections, all of which indicated that the flanges
were not
damaged
by the event.
The inspector discussed
the various
above observations
with licensee
management
who acknowledged
the inspector's
concerns.
The licensee
indicated that they were continuing their investigation into the
incident and would be revising their Incident Investigation
Report
IIR-2-2-89-001 to include
a more thorough review of the
overpressurization
incident.
This report was not complete at the
end of the inspection period.
Pending further inspector
review of licensee corrective actions,
this was identified as
a second corrective action item for
unresolved
item 89-30-05.
No violations of NRC requirements
or deviations
were identified.
Load
Re 'ection
From 100K Power - Unit 2
93702,
92700
On August 4,
1989, at 0822,
MST, Unit 2 experienced
a load rejection
due to a turbine trip from 100% power .
The operators
stabilized the
plant at 40K reactor
power on the Steam
Bypass Control System after
the turbine trip and subsequently
reduced
power to
10% while the
cause of the trip was being investigated.
The licensee initiated
a Catagory
3 investigation
immediately.
The
licensee
found that the turbine trip was initiated from Control
Element Drive Mechanism
(CEDM), Control System
Power
Bus Under
Voltage
(UV) coils that deenergized
with power still present.
The
drop out voltage
as
found to be abnormally high for UV coils
1 and
3, and within acceptable
limits for coils
2 and 4.
Additionally,
the
CEDM Motor Generator
(MG) output voltage
was found to be set at
233 volts rather than the required
240 plus-or-minus
3 volts.
Coils
1, 2, and
3 were replaced
and the output of the
MG sets
was
increased.
No violations of NRC requirements
or deviations
were identified.
II
4
1
Il
f
t
1
l
15
14.
Im ro er Maintenance
on Atmos heric
Dum
Valves Nitro en
Su
1
Re ucin
Re
u ator
a ves
V.
e
u ator
a ves
-
n>t
62 03
The inspector
reviewed- several
completed
work packages
and
interviewed craftsmen,
supervisors,
engineers
and
a vendor
representative,
all associated
with the Unit 2 ADV regulator valves
(2JSGAPCV0310,
2JSGAPCV0317,
2JSGBPCV0303,
and
2JSGBPCV0323)
due to
ongoing difficulties with the operability and reliability of the
ADV
regulators.
Work order No. 00354032 for ADV regulator valve
2JSGAPCV0317
required the valve to be disassembled,
cleaned
and inspected,
and
re-assembled
per technical
manual
No. J091-32 using sections
applicable to MDL No. 7Gg-'010.
This work order was performed from
April 14 to April 16,
1989.
The 'instructions for re-assembly
and
setting the regulator valve contained in the technical
manual
were
not used;
instead
the regulator valve was re-assembled
and set
based
on verbal information obtained
from a vendor representative.
This
assembly
and setting of the regulator valve caused
a continued
lack
of reliability and operability until the valve was reworked in mid
June
1989.
Upon subsequent
rework of the regulator valve, with the aid of a
different vendor representative, it was determined, that the
regulator valves
were incorrectly set
and that proper reassembly
and
setting could be achieved
by following the instructions in the
technical
manual.
Craftsmen,
supervisors,
and quality control personnel
were aware
that the information provided by 'the first vendor representative
deviated
from the technical
manual;
however,
no actions
were taken
to resolve the issue.
Working per verbal information and failing to follow approved
work
orders
and the vendor technical
manual,
which resulted
in lack of
reliability of the
ADV regulator valves, is considered
a violation
of regulatory requirements
(529/89-30-03).
Arizona Public Service
Company
memorandum
No. 260-00112-WCM, dated
June
21,
1989, briefly
describes
the improper maintenance
and
immediate corrective actions.
Work orders
365985,
365995,
365996,
and 365997 for ADV regulator
valves
2JSGBPCV0303,
2JSGAPCV0310,
2JSGAPCV0317,
and
2JSGBPCV0323,
respectively,
were all performed during June 17-20,
1989,
and
required work to be performed
per vendor technical
manual
No. J691-32.
This technical
manual,
dated
November, 5, 1980,
was
superseded
when the vendor issued
a new technical
manual
dated
December
28,
1983.
The
new technical
manual,
No. J691-83,
was
reviewed
by engineering,
plant standards,
engineering evaluation,
and the material control group,
and subsequently
approved
on
April 19,
1989.
The
new manual,
J691-83
was not used or referenced
in the above work orders,
except in an amendment to work order 365997,
where technical
manual
No. J691-83
was required for several
steps
but technical
manual
No. J691-33
was required for a later
step.
It was not clear as to what technical
manual
should
have
been
16
used
on all four of the work orders
and it was not clear that there
were adequate
measures
to ensure that vendor technical
manuals
were
properly controlled to provide the most recent,
approved versions
for maintenance.,
This item is open pending further review
(529/89-30-04).
Inte rated Safe uards Surveillance Testin
- Unit 3
61701
The inspector
reviewed procedure
Revision 1, "Class
1E
Diesel
Generator
and Train "A" Integrated
Safeguards
Surveillance
Test",
and observed
selected
portions of this test.
During the review of the procedure
the inspector
noted that there
was
no mention of pretest briefings
and that the pre-requisites
for
the procedure
were complex and confusing 'in that not all
pre-requisites
are required for each test section
and not all test
sections
indicated the applicable pre-requisites.
The procedure
did
require that the shift supervisor
and test engineer establish
the
pre-requisites
as required.
The inspector
observed
the pre-test briefing for section 8.3 of the
procedure.
The test director briefed the operators
on the
objectives of the test
and the actions
expected of each operator
during the test.
Ouestions
about the test were properly resolved at
this time.
During the test the inspector
observed that the operators
maintained
control of plant conditions
and the test sequence.
When
a
procedural
problem arose,
the inspector
observed that the test
director and shift supervisor
took proper actions to ensure that
plant administrative
procedures
were properly followed.
Problems
identified by the test appeared
to be properly documented
by plant
personnel
to be resolved
by following the proper
Palo Verde Nuclear
Generating Station procedure.
During this test the inspector also observed
operations of the "A"
Train emergency
diesel
generator.
The operator s properly adhered
to
the plant written procedures.
The equipment functioned
as designed.
No violations or deviations of NRC requirements
were identified.
Oualit
Hotline Review
71707)'he
inspector
reviewed the licensee's
Ouality Hotline status
and
selected
several
current
and closed investigations for review.
The
files 'that were reviewed appeared
to address
the concerns,
and
contained
conclusions
and supporting documentation.
The inspector
will continue
t'o followup on selected
Ouality Hotline concerns
in
future inspections.
No violations or deviations of NRC requirements
were identified.
17
17.
Office of Nuclear Reactor
Re ulation
Reviews
18.
Several
issues
associated
with restart of Unit 2 were referred to
NRR for review.
The issues
were as follows:
Multiple Control Element Assembly
(CEA) slippage
Position indication problems with CEA ¹9
tube plug integrity
Low pressure
safety injection header drain valve weld performed
by an unqualified welder.
NRR interfaced directly with the licensee
on these
issues
and
concluded that the licensee's
actions
were acceptable
for restart of
Unit 2.
Review of Periodic
and
S ecial
Re orts - Units
1
2 and
3
90713
Periodic
and special
reports
submitted
by the licensee
pursuant to
Technical Specifications 6.9.1
and 6.9.2 were reviewed
by the
inspector.
This review included the following considerations:
the report
contained
the information required to be reported
by
NRC
requirements;
test results
and/or supporting information were
consistent with design predictions
and performance specifications;
and the validity of the reported information.
Within the scope of
the above,
the following reports
were reviewed
by the inspector.
Unit
1
o
Monthly Operating
Report for June,
1989.
Unit 2
o
Monthly Operating
Report for June,
1989.
Unit 3
19.
20.
o
Monthly Operating
Report for June,
1989.
No violations of NRC requirements
or deviations
were identified.
Unresolved
items are matters
about which more information is
required to determine
whether
they are acceptable
or may involve
violations or deviations.
One
new unresolved
item identified during
the inspection is discussed
in paragraphs ll and
12.
Exit h1eetin
The inspector
met with licensee
management
representatives
periodically during the inspection
and held an exit meeting
on
August 10, 1989.
The licensee
acknowledged
the inspectors
comments
and concerns.
'