ML17347B593
| ML17347B593 | |
| Person / Time | |
|---|---|
| Site: | Turkey Point  |
| Issue date: | 02/14/1990 |
| From: | Butcher R, Crlenjak R, Mcelhinney T, Schnebli G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML17347B591 | List: |
| References | |
| 50-250-89-54, 50-251-89-54, IEIN-84-57, IEIN-89-063, IEIN-89-63, NUDOCS 9003090404 | |
| Download: ML17347B593 (23) | |
See also: IR 05000250/1989054
Text
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0
Cy
n
UNITED STATES
NUCLEAR REGULATORY COMMISSION
REGION II
101 MARIETTASTREET, N.W.
Report Nos.:
50-250/89-54
and 50-251/89-54
Licensee:
Florida Power
and Light Company
9250 West Flagler Street
Miami, FL
33102
Docket Nos.:
50-250
and 50-251
Facility Name:
Turkey Point
3 and
4
License Nos.:
and
Inspection
Conducted:-
Decem
r 23,
1989 through January
26,
1990
Inspector.s:. ~~-..-
R.
C.
Bu
er,
Sen "or Re ident Inspector
I
~g-r Z
F.. Mc~inney,
Reside
Inspector
c
~
G.
A.
S hnebli,
Res'den
Inspector
Approved by:
R.
V. Crlenjak, Section Chief
Division of Reactor Projects
D te Signed
c'c
Date Signed
Z=
/ci
/
Da
e
S gned
Dat
Si
ned
SUMMARY
Scope:
I
This routine resident
inspector
inspection
entailed direct inspection
at the
site
in the
areas
of monthly surveillance
observations,
monthly maintenance
observations,
operational
safety,
plant events
and Management
meetings.
Results:
Two Violations,
one IFI and
one Unresolved
Item were identified:
Violation for closure of an
NCR prior to completion of required actions.
Violation for fai lure to take corrective
action in response
to, terminal
block corrosion identified in November
1988
on Unit 3 MSIVs.
IFI for final root cause
of accelerated
terminal block corrosion.
Unresolved
Item for failure
to
provide
weepholes
for terminal
boxes
containing environmentally qualified terminal blocks.
The inspectors
also noted conservative
operations
when licensee
management
took
Unit 3 offline on December
25,
1989, to replace
corroded terminal blocks.
This
action
was taken at
a time when record
power
demands
forced rotating blackout
periods'"Unresolved
Items
are
matters
about
which more information is required
to
determine
whether they are acceptable
or
may involve violations or deviations.
0
0
REPORT DETAILS
1.
Persons
Contacted
Licensee
Employees
J.
- J
- J
J.
R.
T.
R.
S.
E.
o'G
- V
J.
G.
R.
- L
- D
K.
- G
R.
J.
- F
G.
M.
J.
"A.
V. Abbatiello, Quality Assurance
Supervisor
W Anderson,
Quality Assurance
Supervisor
Arias, Sr. Technical Assistant to Plant Manager
C. Balaguero,
Assistant
Technical
Department
Supervisor
W. Bladow, Quality Assurance
Superintendent
E. Cross,
Plant Manager-Nuclear
J. Earl, Quality Control Supervisor
A. Finn, Assistant Operations
Superintendent
J. Gianfrencesco,
Assistant
Maintenance
Superintendent
T. Hale, Engineering Project Supervisor
N. Harris, Vice President
Hayes,
Instrument
and Controls,
Supervisor
Heisterman, .Assistant
Superintendent
of Electrical Maint
A. Kaminskas,
Technical
Department
Supervisor
A. Labarraque,
Senior Technical Advisor
Marsh,
Reactor
Engineering
Supervisor
G. Mende, Operations
Supervisor
W. Pearce,
Operations
Superintendent
Powell, Regulatory
and Compliance Supervisor
Remington,
System
Performance
Supervisor
M. Smith, Service
Manager - Nuclear
N. Steinke,
Chemistry Supervisor
C. Strong,
Mechanical
Department
Supervisor
R.
Timmons, Site Security Superintendent
S. Warriner, Quality Control, Supervisor
B. Wayland,
Maintenance
Superintendent
D. Webb, Operations - Assistant Superintendent,
Planning
T. Zielonka,, Engineering Supervisor
enance
and Scheduling
Other
licensee
employees
contacted
included
construction
craftsman,
engineers,
technicians,
operators,
mechanics,
and electricians.
- Attended exit interview on January
26,
1990.
Note:
An Alphabetical Tabulation of acronyms
used in this report is
listed in paragraph
11.
2.
Followup on Items of Noncompliance
(92702)
A review
was
conducted
of the
following noncompliance
to
assure
that
corrective actions
were adequately
implemented
and resulted in conformance
with regulatory requirements'erification
of corrective action was
achieved
through record reviews,
observation
and discussions
with licensee
personnel.
Licensee
correspondence
was
evaluated
to
ensure
that
the
2
responses
were timely and that corrective actions
were implemented within
the time periods specified in the reply.
(Closed)
Violation 50-250,251/89-27-04.
Concerning
the installation. of
erroneous
label plates
on the
SI block switch.
The licensee's
actions,
required
by their response
to this violation, (FPL letter L-89-325), dated
September
1,
1989,
were
completed
and
found
to
be
adequate
by the
inspectors.
This item is closed.
(Closed)
URI 50-250,251/89-52-08.
Followup on investigation of NCR 86-421
is
being
closed
by
the
inspectors
without
required
actions
being
completed.
This item concerned deficiencies
found in lead wire insulation
for Limitorque
DC Motors manufactured
by Peerless-Winsmith.
The
subject
NCR required
the
spare
motors
be
returned
to the
vendor
for
repair.
The
NCR was closed
based
on
QC verifying that
recommended
actions
had
been
completed.
The inspectors
were unable to verify the motors
were
sent to the vendor for repair.
After further investigation,
the licensee
determined
the motors were not returned
to the vendor.
There
were three
motors
in question.
Two motors were stored inside the Electrical Depart-
ment
QC locker.
One of these
was
tagged
"Do Not Use"
and after further
review the
motor
was
separated
from it's paperwork
and sent to training.
The other motor in the
QC locker was inspected
and found not to have
the
suspect
motor leads.
This motor was returned to stores.
The third motor
was
stored
in
the
warehouse
without
any
hold
tags.
The
motor
was
inspected
and
found to
have
the
suspect
insulation
on the heater
only.
These
are not used at the plant, therefore,
they were
removed
and the motor
was returned
to stores.
Appendix B, Criterion
XV, as
implemented
by the approved
FPLTQAR 1-76A, Revision
13,
TQR 15.0,
Revision
6, required that
measures
be established
to control materials,
parts,
or components
which do not conform to requirements
in order to
prevent their inadvertent
use or installation.
Furthermore,
nonconforming
items
shall
be reviewed
and accepted,
rejected,
repaired
or
reworked in
accordance
with documented
procedures.
QP 15.2,
Revision 3, required
the
cognizant
QC organization to review and document that specified corrective
actions
from the
NCR are
completed.
15.2 also required that
items
identified
as
discrepant
be controlled
to
ensure
the
items
are
not
inadvertently installed or operated.
Contrary to the above, site
QC closed
86-421
on
May
2,
1988,
without
properly
verifying
the
Peerless"Winsmith
MOV DC Motors were returned to the vendor for lead wire
repair.
Additionally,
a
spare
motor remained
in the
warehouse
without
adequate
controls to preclude inadvertent
use.
This item is identified as
violati on 50-250,251/89"54-01.
Fol 1owup
on Inspector
Fol 1owup Items
(92701)
(Closed)
IFI 50-250,251/88-30-02.
Concerning
the
This issue
was previously discussed
in IRs 50-250,251/88-30
and 89-18.
The
licensee's
corrective
actions
included
installation
of
an
ethylene-propylene
versus
Buna-N
and the installation of lock
washers
on the actuator
cap
screws.
With the exception
of one failure,
which was corrected
by retorquing
on April 5,
1989,
the actions
taken
by
the licensee
appear
to have corrected this problem.
This item is closed.
(Closed)
IFI
50-250,251/88-40-02.
Concerning
the
in stal
1 ati on
of
permanent
labeling for
system
reach
rods.
The inspectors
verified
the permanent
labeling discussed
in this issue
had
been installed.
This
item is closed.
Onsite
Followup
and
In-Office Review of Written
Reports
of Nonroutine
Events
and
10 CFR Part 21 Reviews
(92700/90712/90713)
The
Licensee
Event Reports
and/or
10 CFR Part 21 Reports
discussed
below
were
reviewed
and
closed.
The
inspectors
verified that
reporting
requirements
had been
met,
root cause
analysis
was performed,
corrective
actions
appeared
appropriate,
and
generic
applicability
had
been
considered.
Additionally,
the
inspectors
verified
the
licensee
had
reviewed
each
event,
corrective
actions
were
implemented,
responsibility
for corrective
actions
not fully completed
was clearly assigned,
safety
questions
had
been
evaluated
and resolved,
and violations of regulations
or TS conditions
had been identified.
When applicable,
the criteria of 10 CFR 2, Appendix
C, were applied.
(Closed)
50-250,251/P2185-03.
Concerning faulty AK and
AKR low voltage
power circuit breakers
by
GE.
The
licensee
determined,
by
record
searches,
this
type
breaker
was
not applicable
to the facility and
no
further action
was required.
This item is closed.
(Closed)
50-250,251/P2185-04.
Concerning
possible
damage to control wire
insulation
in
Brown
Boveri
K-Line Circuit
Breakers.
This
issue
was
identified to the
licensee
in
a letter
from the
vendor dated
March
19,
1985 'he
licensee
performed
an
evaluation
which
was
completed
and
documented
under JPE-PTP0-85-820-E,
dated
August 23,
1985. This evaluation
concluded
the
issue
was
not
a
problem
at
the facility and
current
maintenance
procedures
provide for periodic
inspection
of the
breakers
which would be sufficient to identify this problem.
This item is closed.
(Closed)
LER 50"250/88-12.
Concerning
the verification of fire detection
operability
not
being
performed
due
to
weaknesses
in administrative
controls.
The licensee's
actions
required
in this
LER were reviewed
and
found to be adequate.
This item is closed.
(Closed)
50-250,251/P2187-02.
Potential
Overpressurization
of the
System.
In July
1984,
issued
a notification of potential
overpressurization
of the
CCW System
due to
an
RCP thermal barrier heat
exchanger
tube rupture.
The
CCW surge
tank
was provided with
a relief
valve and
a normally open air operated
vent valve.
On
a high radiation
signal
from
CCW radiation
monitors
R-17A
and
B,
the
vent
valve will-
isolate.
During the
postulated
with the
surge
tank relief
valve
setpoint
at
100
psig,
the
maximum
system
pressure
would
be
approximately
220 psig.
The design
pressure
used for
CCW system
stress
analysis
was
150
psig.
The
licensee
performed
a review of the stress
analysis
to identify any piping that
could
be
overstressed
with the
pressure
increase.
The
licensee
concluded
that
the
increased
piping
stresses
would not
exceed
the
ASME Section III Code Stress
Allowables.
The licensee
determined that since this did not pose
a substantial
safety
hazar'd it was not reportable
under
The
licensee
initiated
design
changes
as
recommended
by Westinghouse
to replace
the air operated
vent valve with a normally locked open
manual
valve.
The setpoint of the
relief valve
was to
be
reduced
to
25 psig to protect
the
system
in the
event
the
manual
valve
was isolated.
However,
upon further
review,
the
licensee
discovered
that thi s modification could violate the
CCW closed
system
outside
of
containment
assumption
which
would invalidate
the
containment
isolation design basis,
therefore
the design
changes
were not
implemented.
The licensee
also identified another
concern.
During the
overpressurization
event
and the failure of MOV-626 (CCW from
thermal'arrier
heat
exchangers
isolation) to close
on
a high flow signal,
the
surge tank relief valve will lift. This allows radioactive
gas
and liquid
to enter the waste
hold
up tank which provides
a release
of radioactive
gas
to
the
atmosphere
via the
plant
stack.
This transient
could
be
terminated
by closing
valve
736,
which
is
downstream
of
MOV-626.
analyzed this condition
and determined that the release
would
represent
a
small
fraction of the
10 CFR 100 limits.
The
inspectors
reviewed
ONOP 3108.2,
"High Activity in Component
Cooling Water",
dated
May 16,
1989,
which required
the operator
to isolate
valve
736 in the
event
of
the
surge
tank
relief
valve lifting due
to
overpressurization.
This item is closed.
5.
Monthly Surveillance
Observations
(61726)
The
inspectors
observed
TS required
surveillance
testing
and verified:
The test
procedure
conformed
to the
requirements
of TS,
testing
was
performed in accordance
with adequate
procedures,
test instrumentation
was
calibrated,
limiting cond)tions for, operation
were
met, test results
met
acceptance
criteria requirements
and were reviewed
by personnel
other than
the
individual directing
the
test,
deficiencies
were
identified,
as
appropriate,
and
were
properly
reviewed
and
resolved
by
management
personnel
and
system
restoration
was
adequate.
For
completed tests,
the
inspectors verified testing frequencies
were met and tests
were
performed
by qualified individuals.
The
inspectors
witnessed/reviewed
portions
of
th'e
following test
activities:
3-0SP-050.2
Residual
Heat
Removal
Pump Inservice Test
3/4-0SP-059.5
Power
Range Nuclear Instrumentation Shift Checks
and Daily Calibrations
3/4-OSP-041.
1
Reactor
C'oolant
System
Leak Rate Calculation
No Violations or deviations
were identified in the areas
inspected.
6.
Monthly Maintenance- Observations
(62703)
Station
maintenance
activities of safety related
systems
and
components
were observed
and reviewed to ascertain
they were conducted
in accordance
.
with approved
procedures,
regulatory guides,
industry codes
and standards,
and in conformance with TS.
The following items
were
considered
during this review,
as appropriate:
LCOs
were
met while components
or
systems
were
removed
from service;
approvals
were
obtained
prior
to initiating work; activities
were
accomplished
using approved
procedures
and
were
inspected
as applicable;
procedures
used
were
adequate
to control
the activity; troubleshooting
activities
were controlled
and repair
records
accurately
reflected
the
maintenance
performed;
functional
testing
and/or
calibrations
were
performed prior to returning components
or systems
to service;
gC records
were
maintained;
activities
were
accomplished
by qualified personnel;
parts
and materials
used
were properly certified; radiological controls
were properly
implemented;
gC hold points
were established
and
observed
where
required;
fire
prevention
controls
were
implemented;
outside
contractor
force activities
were
controlled
in
accordance
with the
approved
gA program;
and housekeeping
was actively pursued.
The
inspectors
witnessed/reviewed
portions of the following maintenance
activities in progress:
Troubleshooting
4B
RCP excessive
vibration.
Repair of Unit 4 condenser
internals.
Replacement
of Unit 4B
pump motor upper
end bell
and
pump
mechanical
seal.
Troubleshooting
No violations or deviations
were identified in the areas
inspected.
7.
Operational
Safety Verification (71707)
The inspectors
observed control
room operations,
reviewed applicable
logs,
conducted
discussions
with control
room
operators,
observed
shift
turnovers
and confirmed operability of instrumentation.
The
inspectors
verified
the
operability
of
selected
emergency
systems,
verified
maintenance
work orders
had
been
submitted
as
required
and followup and
prioritization of work was
accomplished.
The inspectors
reviewed tagout
records,
verified 'ompliance
with
TS
LCOs
and verified the
return
to
service of affected
components.
0
By observation
and direct
interviews,
verification
was
made
that
the
physical security plan was being
implemented.
Plant
housekeeping/cleanliness
conditions
and
implementation
of
radiological controls
were observed.
Tours of the
intake
structure,
diesel,
auxiliary, control
and turbine
buildings were conducted
to observe
plant
equipment
conditions
including
potential fire hazards,
fluid leaks
and excessive
vibrations.
The
inspectors
walked
down accessible
portions of the following safety
related
systems
to verify operability and proper valve/switch alignment:
A and
B EDGs
Control
Room Vertical Panels
and Safeguards
Racks
ICW Structure
4160 Volt Buses
and
480 Volt Load and Motor Cont~ol Centers
Unit 3 and
Platforms
Unit 3 and
4 Condensate
Storage
Tank Area
AFW Area
Unit 3 and
4 Main Steam Platforms
Auxiliary Building
a
0
Temporary
Instruction
2515/94.
Inspection
for Verification of
Licensee
Changes
Made
to
Comply
with
Moderator
Dilution
Requirements
Multi-Plant Action Item B-03.
This temporary
instruction was issued to verify those
changes
made to administrative
controls or plant modifications
committed to by licensee's
in their
response
to
DOR
Information
Memorandum
No,7,
"PWR
Moderator
Dilution", issued
October 4,
1977,
have
been completed.
The licensee
responded
to this
issue
in
a letter to
the
NRC,
dated
December
8,
1977.
The
licensee's
evaluation,
indicated
that
no
dilution sources,
other
than
those
previously
analyzed,
had
flow
paths
into the
reactor
coolant
system.
The
NRC responded
to the
licensee's
letter
on
February
21,
1979,
stating
no further action
regarding this generic
issue
was required.
This item is closed.
b.
In
response
to findings
reported
in
Design
Validation Inspection
Report
50-250,251/89-203,
the
inspector s
fol lowed
up
on
the
licensee's
corrective
actions regarding
procedures
3/4-0NOP-30,
step
5.6.3,
which could not
be
implemented
due to the Unit
3
hose
not
being of sufficient length
and Unit 4 did not
have
hoses
provided.
In walking through
procedure
3/4-0NOP-30,
step 5.6.3,
dated
October
10,
1989, the following discrepancies
and/or
comments
were noted.
Step 5.6.3.3 states
to connect
the emergency cooling water hoses
to the Emergency
Hose Connections
on
B charging
pump oil cooler,
3-10-288
and 3-10-289.
The
hose
connection
for 3-70-179A,
Connection Inside Unit 3 Charging
Pump
Room, would not mate with
the
hose
connections
on
the
emergency
cooling
water
hoses
stationed
in Unit 3.
Step
5.6.3
states if
B
charging
pump
is
out
of service,
connections
must
be
installed
on
an
pump.
The
0
emergency
cooling water
hoses
stationed
in Unit 3 and Unit 4
charging
pump
rooms
would not
reach
the
C charging
pump
in
either room.
There
was
no designated
storage
area for the emergency cooling
hoses.
The
hoses
were laid
on the floor in the charging
pump
rooms.
The procedure
does not specify what service water connections
to
use for the
emergency
supply of cooling water
on the loss of
CCW.
SW connection
3-70-179A inside
the Unit 3 charging
pump
room
and
SW connection
4-70-118B outside
the Unit 4 charging
pump
room were utilized during the walkdown.
The licensee
was
made
aware of the
above
comments
and is going to
address
them with a response
to IR 50-250,251/89-203.
No violations or deviations
were identified in the areas
inspected.
8.
Plant Events
(93702)
The following plant events
were reviewed to determine facility status
and
the
need for further followup action.
Plant
parameters
were
evaluated
during transient
response.
The significance
of the event
was evaluated
along with the
performance
of the appropriate
safety
systems
and
the
actions
taken
by the
licensee.
The
inspectors
verified that
required
notifications were
made to the
NRC.
Evaluations
were performed relative
to the
need for additional
NRC response
to the event.
Additionally, the
following issues
were
examined,
as
appropriate:
Details
regarding
the
cause
of the event;
event chronology; safety
system performance;
licensee
.
compliance
with approved
procedures;
radiological
consequences,
if any;
and proposed corrective actions.
On December
23,
1989, with Unit 4 at 94~ power,
a reactor trip occurred at
11: 14 p.m.
due to the closure of the
4A MSIV.
The closure of the
caused
an increase
in pressure
in the
4A SG which caused
the narrow range
level to "shrink" below the low-low level reactor trip setpoint of
15%.
The plant
responded
as
expected,
with
AFW starting automatically.
The
licensee
formed
ERT 89-23 to investigate
the cause
of the event.
The team
determined
that corrosion
across
terminal
block contacts for the
A train
125V
DC opening solenoid valve caused
a fuse to blow.
This de-energized
the solenoid valve to the vent position resulting in air bleeding
from the
bottom of the MSIV piston.
This caused
the
MSIV disc to lower into the
steam flow, resulting in the MSIV rapidly closing..
The
TB was found with
approximately 1/8" of water inside with the cover not fully secured.
The
licensee
decided to inspect additional
TBs to determine
the extent of
water inleakage
and the resultant terminal corrosion.
One terminal
block
on the
4B MSIV and
one block on the Unit 4 feedwater
deck
showed corrosion
similar to the
4A MSIV terminal
block.
These
terminal
blocks
were
replaced.
The
Unit
3
MSIV inspection
revealed
approximately
one .half
gallon of water in the
B train box on the
3C MSIV.
The terminal block had
heavy corrosion.
The
TB cover was sealed
properly and the point of water
entry was not identified.
The
3B MSIV B train
TB had
a small
amount of
water with heavy terminal block corrosion.
The
TB cover was also properly
sealed
and the point of water entry
was not identified.
Similar to the
no weephole
was provided to prevent water accumulations
The licensee
determined that additional
inspections
were required.
These
inspections
included the following areas:
Platform;
Platform;
AFW area;
Turbine Building;
EOG Building; Unit 4 Containment;
Auxiliary Building;
ICW area;
CCW area.
The
ERT reviewed
the inspection
results
to correlate
terminal
block corrosion with water intrusion.
The
results
showed
no correlation
between corrosion
and water intrusion
since
not all
boxes
with water
intrusion
had
corroded
terminals.
The
inspections
did reveal
numerous
minor TB hardware deficiencies
which were
subsequently
resolved.
Since
water
had
to
be
present
for terminal
corrosion,
the licensee
implemented
a weekly inspection
for the
36 boxes
that
showed
evidence
of water
intrusion
until
the
root
cause
of the
terminal block corrosion
was resolved.
Unit 4 was returned to service
on
December
28,
1989, at 6:51 a.m., after resolving all startup
issues.
The
ERT continued its investigation
into the root cause
of the accelerated
corrosion of the
GE Type
EB25 terminal blocks.
Issues
covered during the
investigation
included the root cause of the terminal block corrosion
and
the lack of drainage
(weephole) for the
TBs and are discussed
below:
1.
Root Cause of Terminal Block Corrosion.
The
EQ Doc Pac (No.
13. 1) for the
EB25 terminal blocks specified
that they are qualified for aging of 40 years.
The terminal
blocks
were in place
for approximately
one year prior to this
failure.
The
EB25 terminal blocks were required to be inspected
for corrosion,
dirt,
and deterioration
every refueling
outage.
NRC IR 50-250,251/87-08
identified corrosion
on
a terminal block
located
in
TB 4120
on the Unit 4 feedwater
deck.
The licensee
added
the
inspection
requirement
to
ADM-704,
Environmental
Qualification Maintenance
Index,
EQ Tab.
13, in response
to the
finding.
However,
the Unit 4 MSIV terminal blocks
had corroded
before
their
scheduled
inspection.
Therefore,
the
licensee
investigated
the reason
for the accelerated
corrosion
on these
terminal
blocks.
The corroded
block from the
4A MSIV was sent
to a laboratory for chemical analysis.
The laboratory concluded
the
cause
of corrosion
was high moisture
in contact with zinc
plated
steel
screws
coupled with other materials
such
as tin,
over brass,
brass
fittings secured
with nickel plated
brass
screws.
These
dissimilar
metals
set
up
a
galvanic
reaction
which
was
enhanced
by the
presence
of chlorine.
In
addition to chemical testing,
the licensee
performed
a detailed
inspection
of
TBs externally
and internally, listing various
attributes.
A matrix was
formed with the attributes to identify
any commonality
between
the boxes.
The licensee
also performed
an accelerated
corrosion test of the
EB25 terminal blocks inside
a salt
fog chamber.
The final root cause
of the accelerated
corrosion
and the corrective
actions
was not completed
at the
end of the inspection
per iod.
This item is identified as IFI
50-250,251/89-54"03.
The
licensee
determined
that similar corrosion
had
occurred
previously.
88-214
identified,
in early
November
1988,
corroded terminal blocks in TBs
3930A,
3932A,
3933B,
3934B
and
3935B,
which are
located
on
the
Unit
3
MSIV Platform.
The
terminal blocks
(GE
EB25)
were installed for approximately
one
year
when
they exhibited
the corrosion.
The terminal blocks
were replaced with identical
EB25 blocks and the corroded
block
was sent to an offsite laboratory in an effort to determine
the
cause of corrosion.
The disposition specified
on the
NCR was to
forward
the results
of the
tests
to Project
Engineering for
evaluation.
The
analysis
report
from the
laboratory
dated
December
16,
1988,
attributed the primary cause
of corrosion to
the terminal
blocks
exposure
to
a
high chlorine
environment.
However,
no corrective
actions
were initiated to address
the
buildup of corrosion products
on the terminal blocks.
The failure to initiate corrective actions constitutes
a
violation of NRC requirements.
10 CFR 50, Appendix B, Criterion
XVI, as
implemented
by the approved
FPLQTAR 1-76A. revision
15,
TQR 16.0, revision 5, required that in the
case
of significant
conditions
adverse
to quality, the cause of the condition shall
be determined
and action taken to preclude repetition.
QP 16. 1;
revision
9,
required
each
organization establish
a
system to
followup and assure
completion of corrective
action resulting
from their respective
audits,
inspections,
surveillances,
tests
or operations.
2. 17,
revision
1,
required
the
cause
of
failure for any
EQ component
be documented,
and it needed to be
determined if the
cause
was related
to
a
service
environment
failure mode or not.
Subsequently,
Unit 4 experienced
a reacto~ trip on December
23,
1989, which was caused
by the
4A MSIV closing.
The closure of
the
4A MSIV was attributed
to terminal block corrosion leading
to
a short circuit between
contacts,
blowing
a control
power
fuse.
Additionally, the
40 years
specified life of the terminal
blocks
was
not
met
since
the
blocks
were
installed
for
approximately
one year before failure. This item is identified
as Violation 50-250,251/89-54-02.
Lack of Weepholes
in TBs
The licensee
found approximately
1/8 " of water inside the
4A
MSIV and approximately
6" (1/2 gallon) of water inside the
3C
The licensee
also identified that the
TB cover
was not properly secured
for the
4A MSIV TB which could account
for the water intrusion.
However,
the
3C
secured
properly.. This
led the
licensee
to believe the water could be
entering
from inside the conduit
system
or through
the conduit
0
10
hubs
entering
the
TB.
Since
the
conduit
system
was
not
completely
sealed,
water could enter at
a high point and drain
to
a low point.
These
TBs did not
have
a weephole
to prevent
water, accumulations
The TBs were installed during the previous
Unit 4 refueling outage.
They were specified
as
being
NEMA 4
Stainless
Steel
TBs.
This meant they were weatherproof but not
necessarily
watertight.
The specification
that
was
used
for
installation
did not require
these
TBs to
have
a
weephole.
Problems
related
to
moisture
intrusion
in
safety-related
electrical
equipment
were addressed
in
NRC IN 84-57, dated July
17,
1984.
A study by the Office of
AEOO revealed
that
most of
the electric
components
were
shor t-circuited
and
corroded
when
failure occurred.
In most
cases,
the
shorting
was
caused
by
moisture
leaking into the equipment
housing
and junction boxes.
Contributing factors to the moisture intrusion included:
(1)
installed
equipment
had
lost
its
environmental
protection
boundary
as
a
result
of
maintenance
activities.
(2)
unsealed
conduits
and
other
possible
pathways
were
allowed to exist that permitted moisture to leak into
the equipment
housing.
(3)
moisture
and
steam
may
have
entered
at
unsealed
conduit
ends
located
at
higher
elevations
which
eventually went to equipment at lower elevations
~
Additionally, the
NRC
issued
on
September
5,
1989,
alerting
licensees
that electrical circuits within electrical
enclosures
could
become
submerged
in water if appropriate
drainage
was
not provided.
This notice further
emphasized
the
information contained
in IN 84-57 concerning
the
TB drain holes
and
the
conformance
with the
EQ test
set
up.
The
licensee
addressed
IN 84-57 in September
1985.
Electrical
Maintenance
Department
recommended
emphasizing
proper
work practices
in
future training
and
a
change
to
MOV procedures
to
check for
moisture
problems.
18C
Department
evaluated
the
problem
and
determined that all safety related
equipment installed required
environmental
seals
such
as
NEMA enclosures
and
the
use
of
Raychem seals.
This related to installations inside containment
which would be subject to the harsh
post-LOCA environment,
which
were
EQ items.
However,
since this time,
EQ terminal
blocks
were
installed
outside
containment
subject
to
an
HELB harsh
environment.
Additionally,
had not experienced
electrical
circuit
shorts
due
to moisture
intrusion to safety
related
equipment.
Therefore,
the
only action
taken
by
18C
was
to
counsel
the supervisors
and technicians
on this issue.
was in the review process
at the time of the event,
therefore
no
action
had
been
completed.
Engineering
has provided
a revision
to the
design
documents
to
include
drainage
holes
in future
4
0
installations.
The final recommendation
on backfitting existing
boxes with drainage
holes will be
made after
the final root
cause
i s determined
of the
MSIV fuse failure.
The
Eg testing
performed
for the
ES25
terminal
blocks
simulated
a
environment.
The
blocks
were installed
inside
a
TB provided
with a weephole.
The weephole
was to prevent
submergence
of the
terminal blocks during the test,
where pressures
between
47 psig
58 psig
were
experienced.
The pressurization
would force
steam
into the enclosures
and
subsequently
condense.
The MSIV
TBs were located in an outdoor area
and were required
to remain
functional
for
30
minutes
at
212
degrees
F at
atmospheric
pressure.
There would be less
tendency to drive steam into the
enclosure.
However,
since
the
TBs were not able to keep water
from entering,
water
was able
to accumulate.
The worst
case
identified was on'he
3C MSIV which had the lower portion of the
terminal block submerged.
The
8 point terminal block only used
the
upper
4 points,
therefore,
the
submergence
did not affect
the operability of the
MSIV.
However,
more
water
could
have
entered
the enclosure
and possibly
cover
an energized
contact.
At the time of inspection,
the licensee
was in the
process
of
determining
what effect
the
lack of TB weepholes
had
on the
terminal
block
environmental
qualification.
Therefore,
this
item will be tracked
as
URI 50-250,251/89-54-04.
On December
24,
1989, with Unit 3 at
100% power, the licensee
declared
the
3B and
3C MSIVs inoperable'he
licensee
had performed inspections
on the
Unit
3
MSIV terminal
blocks
following the
December
23,
1989,
Unit
4
reacto~ trip discussed
above.
The licensee
found similar corrosion
on the
3B and
3C MSIVs.
The licensee
made
a conservative
decision to declare
the
valves inoperable
and take Unit 3 offline.
TS 3.8 required all
MSIVs be
when
RCS temperature
exceeded
350 degrees
F. If this condition
could not be met within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />,
the reactor
was to be
shutdown
and
temperature
reduced
below
350
degrees
F.
With
more
than
one
TS 3.0. 1
is
entered.
Since
two
were
declared
TS 3.0. 1 was entered
at 11:00 p.m.
Unit 3 was brought to Mode
2.
The terminal strips for the
3B and
3C MSIVs were
replaced
and
the
valves
were declared
at 4:55 a.m.
on December
25,
1989.
Unit 3
was returned to service at 8:50 a.m. that day.
On
January
9,
1990,
Unit
4
was
shutdown
to
troubleshoot
excessive
vibration of the
4B
RCP motor and to repair various
components
which could
cause
a Unit 4 shutdown during the upcoming Unit 3 refueling outage.
The
4B
RCP vibration
had
increased
to approximately five mi ls,
which is the
upper limit recommended
by the vendor,
Balance weights were
added to the
pump coupling
and vibrations were decreased
to less
than
one
mil, well within acceptable
limits.
The additional
equipment
repaired
during this mini-outage to ensure reliability included:
( 1) Replacement
of
4B
pump
motor
upper
end bell
due
to
a slight
. oil
leak;
(2)
replacement
of
4B
RHR .pump
mechanical
seal;
(3) detailed
inspection
of
Unit
4
Condenser
to identify the
cause
of
numerous
tube
leaks.
This
inspection
revealed that portions of the shroud
around
0
0
12
had broken loose
from its mountings
and the loose
sheet
metal
was beating
against
the tubes
causing
some of the
tube
leaks previously identified.
The loose
shroud
was
removed or repaired
and additional
suspect
tubes
were
plugged.
All foreign material
found during this inspection
was
removed;
(4) repairs
to
4A Containment
Pump Float Switch; (5) repacking
and
furmaniting of several
leaking valves
and flanges;
(6) replacement
of B-6
RPI cable;
(7) Ray-Chem
MSIV terminal connections.
The unit was returned
to service
on January
19,
1990, which was slightly over two days
ahead of
schedule.
9.
On January
12,
1990,
at
10:43 a.m., while performing liquid release
from
the
B MT per
LRP 90-027,
PRMS R"18 (Liquid Release
Gross Activity Monitor )
failed.
There
was
no display indication,
the chart recorder failed high
and
no automatic
closure of RCV-018 occurred.
The tank had
been
sampled
and analyzed prior to initiating the release
and was independently
sampled
and
analyzed
fo 1 l owi ng
the fa i 1 ure
of
R-18.
The
1 icen see
made a,
significant event report
per
The'icensee's
sample
results
were within acceptable
limits prior to
and following the
liquid release.
PRMS-18 was tested satisfactorily
and returned to service
at 4:25 p.m.
on January
13,
1990.
Management
Meetings (94702)
A management
meeting
was
held
on January
9,
1990,
and was the fourteenth
in a series of management
meetings
between
the
NRC and
FPL following the
issuance
of Confirmatory
Order
87-85
in
October
1987.
The
previous
meeting
was held
on September
19,
1989,
and the
SALP meeting
was held at
the site
on October 26,
1989.
A plant tour
was conducted
by the resident
inspectors
to update
NRC Management
on plant conditions.
The
licensee
made
presentations
on
the
operating
history
since
the last
management
meeting,
initiatives
in
the
planning
and
scheduling
department,
improvements
in maintenance
indicators,
involvement
of engineering
and
technical
support
system
engineers
in resolving plant problems,
security
upgrade
status,
gA effectiveness
by
means
of self
assessment
and
improvements.
On January
22,
1990,
Commissioner
J.
R,
Curtiss visited
the site for
discussions
with
the
Resident
Inspectors
and
management.
The
Commissioner attended
the
morning
Plan-Of-The-Day
meeting,
followed by
a
plant tour conducted
by the
licensee.
Following the tour,
the
licensee
made
presentations
concerning
corporate
organization,
general
plant
performance
overview including training,
maintenance
indicators,
system
engineer
program,
use
of
self
assessments,
security
upgrades
and
performance,
and
the
upcoming dual unit outage
including the
emergency
power upgrade.
10.
Exit Interview (30703)
e
The
inspection
scope
and
findings
were
summarized
during
management
interviews
held throughout
the reporting
period with the Plant Manager-
Nuclear
and selected
members
of his staff.
An exit meeting
was
conducted
13
on
January
26,
1990.
The
areas
requiring
management
attention
were
reviewed.
No proprietary
information
was
provided
to
the
inspectors
during the reporting period.
The inspectors
had the following findings:
50-250,251/89-54-01,
Violation.
Closure
of
an
prior
to
completion of required actions.
(paragraph
2)
50-250,251/89-54-02,
Violation.
Failure to take corrective action in
response
to terminal
block corrosion
identifed in November
1988
on
the Unit 3 MSIVs.
(paragraph
8)
50-250,251/89-54-03,
- IFI.
Followup
on
final
root
cause
of
accelerated
terminal block corrosion.
(paragraph
8)
50-250,251/89-54-04,
URI.
Weepholes
not provided for terminal
boxes
containing environmentally qualified terminal blocks.
(paragraph
8)
Acronyms and Abbreviations
ADM
ANSI
CFR
DOR
ERT
FPLTQAR
ICW-
IEB
IFI
IN
IR
LCO
LER
LRP
MSIV .
al
Data
e Report
Administrative
Office for Analysis
and Evaluation of Operation
American National Standards
Institute
Administrative Procedures
American Society of Mechanical'nmgineers
Component
Cooling Water
Code of Federal
Regulations
Division of Research
Emergency Diesel
Generator
Environmental Qualification
Event Response
Team
Florida Power
8 Light
Florida Power
8 Light Topical Quality Assuranc
Final Safety Analysis Report
General
Electric
High Head Safety Injection
Intake Cooling Water
Inspection
and Enforcement Bulletin
Inspector
Followup Item
Independent
Management
Apprais'al
Information Notice
Inspection
Report
Limiting Condition for Operation
Licensee
Event Report
Liquid Release
Permit
Motor Operated
Valve
Maintenance
Procedures
Monitor Tank
14
NRC
ONOP
OP
PRMS
TQR
TS
Non-conformance
Report
National
Equipment Manufactures
Association
Non-Cited Violation
Nuclear Regulatory
Commission
Off Normal Operating
Procedure
Operating
Procedure
Power Operated Relief Valve
Plant Supervisor
Nuclear
Process
Radiation Monitoring System
Pressurized
Water Reactor
Quality Assurance
Quality Control
Quality Procedure
Pump
Radiation Control Valve
Residual
Heat
Removal
Rod Position Indication
Systematic
Assessment
of Licensee
Performance
Terminal
Box
Topical Quality Requirement
Technical Specification
Unresolved
Item