ML16342A842
| ML16342A842 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 06/25/1999 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | |
| Shared Package | |
| ML16342A843 | List: |
| References | |
| 50-275-99-06, 50-275-99-6, 50-323-99-06, 50-323-99-6, NUDOCS 9907060172 | |
| Download: ML16342A842 (28) | |
See also: IR 05000275/1999006
Text
ENCLOSURE
U.S. NUCLEAR REGULATORY COMMISSION
REGION IV
Docket Nos.:
License Nos.:
Report No.:
Licensee:
Facility:
Location:
Dates:
Inspectors:
Approved By:
50-275
50-323
DPR-82
50-275/99-06
50-323/99-06
Pacific Gas and Electric Company
Diablo Canyon Nuclear Power Plant, Units 1 and 2
7 ~/a miles NW of Avila Beach
Avila Beach, California
April 18 through May 29, 1999
David L. Proulx, Senior Resident Inspector
Dyle G. Acker, Resident Inspector
James
F. Melfi, Project Engineer
CliffordA. Clark, Reactor Inspector.
Linda J. Smith, Chief, Project Branch E
ATTACHMENT: Supplemental Information
'P'P070b0i72
990b25
ADQCK 05000275
8
EXECUTIVE SUMMARY
Diablo Canyon Nuclear Power Plant, Units
1 and 2
NRC Inspection Report No. 50-275/99-06; 50-323/99-06
This inspection included aspects of licensee operations, maintenance,
engineering, and plant
support.
The report documents inspection performed during a 6-week period by the resident
inspectors.
~Oerations
Two examples of a noncited violation of Technical Specification 6.8.1.a, in accordance
with Appendix C of the NRC Enforcement Policy, were identified for failure to follow
procedures.
In the first example, carpenters installed a scaffold that blocked a fire
suppression sprinkler in the area of a component cooling water pump, in violation of the
scaffolding procedure.
In the. second example, operators improperly implemented
Equipment Control Guideline 18.4, after declaring the fire suppression
system
inoperable in the area of component cooling water Pump 1-3. Operators initiated an
hourly fire tour instead of a continuous firewatch as required by Equipment Control
Guideline 18.4. The fire protection engineer performed a subsequent
review that
determined that the fire suppression
system was degraded,
but operable.
Four other
recent operator errors, with respect to implementation of the Equipment Control
Guidelines, indicated that improvement was necessary
in this area.
These two
examples of the violation were placed in the corrective action program as Action
Requests A0485075 and A0484540 (Section F1.1).
Maintenance
Maintenance and surveillance activities observed were performed properly
(Sections M1.1 and M1.2).
~En ineerin
I
The design change package associated
with the auxiliary saltwater vault drain system
was an example of sound enginee'ring and was designed to improve the reliability of the
associated
The licensee installed y-strainers and low-point drains to help
remove foreign material from the drain system to minimize fouling of the check valve
seating surfaces (Section E1.1).
A noncited violation, in accordance with Section VII.B.1 of the NRC Enforcement Policy,
was identified for failure to implement Technical Specifications 4.0.5 and 3.7.3.1.
Specifically, in July 1997, the licensee used pump curves instead of the required
reference values in development of acceptance
criteria for inservice testing of the
component cooling water pumps.
The licensee subsequently submitted a relief request
to correct this violation (Section E8.2).
-2-
Plant Su
ort
Routine radiation protection practices were performed well in that personnel donned
protective clothing and dosimetry properly apd that radiological barriers were properly
posted (Section R1.1).
Routine security activities were performed well in that the security officers were alert at
their posts, security boundaries were being maintained properly, and screening
processes
at the Primary Access Point were performed properly (Section S1.1).
Summa
of Plant Status
Unit 1 began this inspection period at 100 percent power.
Unit 1 continued to operate at
essentially 100 percent power until the end of this inspection period.
Unit 2 began this inspection period at 100 percent power.
On April25, 1999, operators reduced
power to 50 percent to support cleaning in the circulating water tunnels.
Following completion
of the circulating water tunnel cleaning, operators returned Unit 2 to 100 percent power on
May 1. Unit 2 continued to operate at essentially 100 percent power until the end of this
inspection period.
I. ~Oerattone
01
Conduct of Operations
01.1
General Comments
71707
The inspectors visited the control room and toured the plant when on site, including
periodic backshift inspections.
Overall, the performance of plant operators reflected a
focus on safety.
Operators frequently implemented self- and peer-checking
in the
performance of routine duties. The use of three-way communications continued to
improve, and operator responses
to alarms were observed to be prompt and appropriate
to the circumstances.
The inspectors noted that operators carefully conducted power maneuvers to support
the Unit 2 circulating water tunnel cleaning, in accordance with procedure requirements.
II. Maintenance
M1
Conduct of Maintenance
a.
Ins ection Sco
e 62707
The inspectors observed portions of work activities covered by the following work
orders:
Work Order
C0161922
~Deacri tion
Centrifugal Charging Pump 2-1 Attempt to Correct Gear Oil Hl
Temperature
-2-
R0189573
R0167678
Calibration of Centrifugal Charging Pump 2-1 Gauge Pl-782
Inspection and PM of CS-2-9001B, with Replacement of Torque
Limiter Plate Per MMD M000073
R0187659
C0128646
Preventive Maintenance on Containment Spray Pump 2-2
Install Splice Plates for Residual Heat Removal Pump 2-1 Seismic
Supports
b.
Observations and Findin s
The inspectors concluded that the applicable work orders were performed properly.
Operators initiated the clearances
properly, and probabilistic risk assessments
were
satisfactorily performed prior to the work.
M1.2
Surveillance Observations
a.
Ins ection Sco
e 61726
The inspectors obse'rved portions of the performance of Procedure STP M-9A, "Diesel
Generator Routine Surveillance Test," Revision 53A, and Procedure STP M-89,
"Emergency Core Cooling System Venting," Revision 28.
b.
Observations and Findin s
The inspectors found that the licensee performed these surveillance tests properly and
documented the data properly. Operators satisfactorily performed risk assessments
'rior
to removing the applicable systems from service.
M8
Miscellaneous Maintenance Issues (92700, 92902)
M8.1
Closed
Licensee Event Re ort LER 50-323/97-005-00:
Reactortripandsafety
injection caused by inadvertent main steam isolation valve closure because of personnel
error.
This issue was discussed
in detail and dispositioned in NRC Inspection Report
50-275; 323/97-19.
No new issues were revealed upon review of this LER.
-3-
E1
Conduct of Engineering
E1.1
Desi
n Chan
e Packa
e Review
a.
Ins ection Sco
e 37551
The inspectors reviewed Design Change DCP P-49392 to determine if the proper
design controls were implemented.
b.
Observations and Findin s
The licensee implemented Design Change DCP P-49392 during Refueling Outage 1R9.
The purpose of this design change was to install newly designed check valves,
y-strainers, and low-point drains on the Unit 1 auxiliary saltwater pump vault drains to
improve the reliability of the associated
NRC Inspection Report 50-275;
323/97-14 identified several issues associated
with the auxiliary saltwater pump vault
drain check valves.
These valves were noted to be unreliable, since these check valves
were found to be stuck in the open position during periodic surveillances because
of
foreign material on the seats.
This rendered the check valves unable to perform their
intended safety function of preventing back flow into the auxiliary saltwater pump vault
during postulated intake structure flooding. Design Change DCP P-49392, which
installed y-strainers and low-point drains upstream of the check valves, was developed
to help minimize the deposition of foreign material on the check valve seating surfaces.
The inspectors also reviewed the as-built drawings and applicable preventive
maintenance
instructions and noted that these items were satisfactorily revised to reflect
Design Change DCP P-49392.
From these reviews, the inspectors determined that
Design Change DCP P-49392 was an example of sound engineering.
c.
Conclusions
The design change package, associated
with the auxiliary saltwater vault drain system,
'as
an example of sound engineering and appeared to improve the reliability of the
associated
Miscellaneous Engineering Issues (92700)
E8.1'losed
Ins ection Followu
Item
IFI 50-275 323/97003-01:
periodic testing required
for main feedwater pump turbine stop valves.
This foilowup item was opened after a loss of main feedwater Pump 2-1 and a reactor
trip on March 29, 1997, when the licensee discovered that the main feedwater pump
turbine stop valves had a design basis specification to close within 5 seconds, but were
not tested to verify this criterion. This followup item involved reviewing the licensee's
resolution for testing of the stop valves.
-4-
Backcaround
After a reactor trip, the licensee identified an equipment problem with the main
feedwater Pump 2-1 governor valve, in which it did not shut promptly because
of
particulates in the main feedwater Pump 2-1 control oil system.
The licensee resolved
this problem, but also questioned other aspects of the main feedwater pump control
system, including whether this failure could affect the main feedwater turbine stop
valves.
A quality assurance
audit determined that certain design basis
accident'equences
relied upon these turbine stop valves to close to limitthe amount of
. feedwater entering containment by stopping the main feedwater pumps.
Further review
identified that the main feedwater pump stop valves were not tested to verify that they
would satisfy the design basis requirements.
The inspectors opened the followup item
to assess
the licensee's resolution of not testing these stop valves.
Assessment
At the time of the reactor trip, the licensee performed a prompt operability assessment
that concluded that the valves were operable based upon startup tests performed on the
main feedwater pumps.
The inspectors found that the licensee implemented
surveillance procedures to test these valves and issued License Amendment Request
98-05 on August 10, 1998, to include a trip response time for the main feedwater
pumps.
The licensee tested these valves using'Procedure
STP V-3P7, "Timing Test-
Main Feedwater Pump Stop Valves." The inspectors considered the licensee's actions
appropriate.
The licensee had Technical Specifications (TSs) that did not assure that the design
basis was maintained for the plant. Title 10 CFR 50.36(c)(2)(ii)(C) states that a TS
limiting condition for operation must be established, for each item that is a structure
.
system or component that functions to mitigate a design basis accident or transient that
presents a challenge to the integrity of a fission product barrier.
Limiting how much
feedwater enters containment was considered important for a postulated feedwater line
or steam line break in containment to limitthe height of water in containment or the
extent of a cooldown of the reactor coolant system.
However, 10 CFR 50.36(c)(2)(iii)
states that licensees are not required to revise TSs issued prior to April 1995 to meet
the requirement concerning the proper content of limiting conditions for operation.
Because the TSs were initiallyissued without including the surveillance of the main feed
pump turbine stop valves, no violation of NRC requirements occurred and this followup
item is closed.
Closed
LER 50-275/97-012-00:
TSs 3.7.3.1 and 4.0.5 not met because
of personnel
error.
In July 1997, the licensee identified that the inservice testing requirements were not met
for component cooling water (CCW) Pump 1-3, because
of an inadequate test
procedure.
This error occurred, in part, because
of changes
in code requirements for
the second 10-year inservice testing interval and a failure to implement required
procedure changes before the next required inservice test.
The CCW pump test
-5-
F
procedure did not comply with TS 4.0.5 and ASME Operations and Maintenance Part 6
requirements as clarified by NUREG-1482. The licensee used pump curves instead of
reference values in determining the acceptance
criterion.
The licensee revised the surveillance test procedures for the CCW pumps to comply
with ASME Operations and Maintenance Part 6, prior to subsequent surveillance tests.
~
Anaiysis of the test results did not show any actual degradation of CCW Pump 1-3.
As corrective actions for this LER, the licensee submitted a relief request to allow using
pump reference curves for the CCW pump testing and performed an Independent
assessment
of the inservice testing program to ensure that all required relief requests
have been submitted.
The licensee received approval for the relief request for the CCW
pumps on February 25, 1998. The licensee has also submitted a relief request for the
auxiliary saltwater pumps.
The inspectors determined that the failure to test CCW Pump 1-3 in accordance
with the
ASME code was a violation of TSs 4.0.5 and 3.7.3.1.
This nonwillful, licensee-identified
and corrected violation is being treated as a noncited violation consistent with
Section VII.B1 of the NRC Enforcement Policy (50-275/99006-01).
E8.3
Closed
LER 275 323/97-003-00:
Reactor vessel level indication system outside
design basis due to personnel error and inadequate vendor communication.
This LER identified an error with their calibration of their reactor vessel level indication
system during an evaluation for the transition to a 24-month fuel cycle. This situation
was discussed
in NRC Inspection Report 50-275;323/97-02.
The inspectors reviewed
this LER and did not identify any new issues, and concluded that the
licensees'orrective
actions were adequate.
This LER is closed.
R1
R1.1
Radiological Protection and Chemistry Controls
T
General Comments
71750
S1
S1.1
The inspectors evaluated radiation protection practices during plant tours and work
observation.
The inspectors determined that routine radiation protection practices were
performed well in that personnel donned protective clothing and dosimetry properly and
that radiological barriers were properly posted.
Conduct of Security and Safeguards Activities
General Comments
71750
During routine tours, the inspectors assessed
the conduct of security and safeguards
activities. The inspectors concluded that routine security activities were performed well
in that the security officers were alert at their posts, security boundaries were being
maintained properly, and screening processes
at the Primary Access Point were
performed properly. During backshift inspections, the inspectors noted that the
protected area was properly illuminated.
Control of Fire Protection Activities
Scaffoldin
Controls
Ins ection Sco
e 71707
The inspectors evaluated the effect of installed scaffolding on safety-related structures,
systems, and components.
Observations and Findin s
Scaffolding Installation
During tours of the facility, the inspectors evaluated the effect of installed scaffolding on
safety-related systems with respect to fire protection.
On May 19, 1999, the inspectors
noted that carpenters erected a scaffold above CCW Pump 1-3. The licensee used this
scaffold for work on penetration seals.
The inspectors noted that the scaffold had the
appropriate seismic qualification and did not interfere with CCW system operation.
However, the inspectors noted that the carpenters installed the scaffold platform such
that the platform blocked the fire suppression sprinkler nozzle above CCW Pump 1-3.
The inspectors were concerned that the fire suppression
capabilities were impaired
without compensatory measures
and notified the shift supervisor of this deficiency..
The shift supervisor inspected the scaffold and agreed that the scaffold impaired the
functionality of the fire suppression system.
The shift supervisor initiated Action
Request (AR) A0485075 to e'nter this item into the corrective action system.
In addition,
the shift supervisor added the impaired sprinkler to the hourly firewatch tour.
The inspectors noted that Procedure AD7.ID5, "Scaffold Material Structures,"
Revision 4A, Section 6.3.7.g, stated that scaffold structures shall not block
passageways,
walkways, fire suppression
equipment, emergency lighting, or personnel
exits. Because carpenters erected a scaffold that obstructed a sprinkler near CCW
'Pump 1-3, the licensee did not comply with this procedure.
TS 6.8.1.a requires the
licensee to implement procedures as recommended
Appendix A, Revision 2. Regulatory Guide 1.33, Appendix A, recommends
administrative procedures,
and Procedure AD7.ID5 partially implemented this
requirement.
Therefore, failure to implement Procedure AD7.IDS is the first example of
a violation of TS 6.8.1.a.
However, this Severity Level IVviolation is being treated as a
noncited violation, consistent with Appendix C of the Enforcement Policy. This violation
example is in the corrective action program as AR A0485075 (50-275/99006-02,
Example 1).
-7-
Licensee investigation of this issue revealed that Procedure AD7.ID5 provided thorough
instructions for the carpenters to follow to ensure that safety-related systems were not
impaired during scaffold installation.
However, Procedure AD7. ID5 contained only
vague direction with respect to operator and engineering walkdowns of scaffolds. The
licensee was evaluating enhancements
to Procedure AD7.ID5 at the end of the
inspection period.
b.2
Operator Response
to Scaffold Problem
The inspectors subsequently reviewed the operator response
to the deficient scaffold.
The inspectors noted that operators considered the fire suppression system for the
vicinityof CCW Pump 1-3 inoperable and implemented Equipment Control
Guideline 18.4, "Sprinkler/Spray Systems."
Equipment Control Guideline 18.4 required
that, if a fire suppression sprinkler system was inoperable in an area containing fire
protection safe shutdown equipment, a continuous firewatch was required.
If a fire
suppression sprinkler or spray system was inoperable in an area without safe shutdown
equipment, an hourly firewatch tour of the area was required.
The licensee's safe
shutdown analysis credited the CCW pumps; therefore, upon discovery that the fire
suppression sprinkler was inoperable, a continuous firewatch was required.
However, operators mistakenly directed that the area of CCW Pump 1-3 be added to
the hourly firewatch tour because of insufficient knowledge of Equipment Control
Guideline 18.4. AR A0484540 and Quality Evaluation Q0012134 were updated to
include this operator error. Quality Evaluation Q0012134 contained four additional
examples of operators failing to properly implement Equipment Control Guidelines.
The
licensee addressed
these errors on a generic basis.
The inspectors considered the
licensee response
to operator performance issues appropriate.
Procedure OP1.DC16, "Control of Plant Equipment not Required by the Technical
Specifications," Revision 2A, Section 5.4.4, stated that the required actions of the
Equipment Control Guidelines shall be implemented.
Because the operators failed to
properly implement Equipment Control Guideline 18.4 when the fire suppression system
was inoperable, this procedure requirement was not met.
TS 6.8.1.a requires the licensee to implement procedures as recommended
in
Regulatory Guide 1.33, Appendix A, Revision 2. Regulatory Guide 1.33, Appendix A,
recommends administrative procedures,
and Procedure OP1.DC16 partially
implemented this requirement.
Therefore, failure to implement Procedure OP1.DC16 is
the second example of a violation of TS 6.8.1.a.
However, this Severity Level IV
violation is being treated as a noncited violation, consistent with Appendix C of the
Enforcement Policy. This violation example is in the corrective action program as
AR A0484540 (50-275/99006-02, Example 2).
The licensee's fire protection engineer evaluated the as-found condition of the scaffold.
The fire protection engineer noted that, although the sprinkler above the scaffold
platform could not perform its function, another sprinkler head existed in the area of the
pump. Therefore, the fire protection engineer determined that the fire suppression
0
-8-
system in the area was degraded but operable.
The fire protection engineer directed
that, as a prudent compensatory'measure,
an hourly firewatch tour be in place and no
combustible materials be allowed in the vicinityof CCW Pump 1-3. The inspector
determined that these measures
were appropriate.
Conclusions
Two examples of a noncited violation of TS 6.8.1.a, in accordance
with Appendix C of
the enforcement policy, were identified for failure to followprocedures.
In the first
example, carpenters installed a scaffold that blocked a fire suppression sprinkler in the
.
area of a CCW pump, in violation of the scaffolding procedure.
In the second example,
operators improperly implemented Equipment Control Guideline 18.4, after declaring the
fire suppression system inoperable in the area of CCW Pump 1-3. Operators initiated
an hourly firewatch tour instead of a continuous firewatch as required by Equipment
Control Guideline 18.4. The fire protection engineer performed a subsequent
review
that determined that the fire suppression
system was degraded but operable.
Four
other recent operator errors, with respect to implementation of the Equipment Control
Guidelines, indicated that improvement was necessary
in this area.
These two
examples of the violation were placed in the corrective action program as
ARs A0485075 and A0484540.
V. Mana ement Meetin s
X1
Exit Meeting Summary
L
The inspectors presented the inspection results to members of licensee management at the
conclusion of the inspection on June 9, 1999. The licensee acknowledged the findings
presented.
The inspectors asked the licensee whether any materials examined during the inspection
should be considered proprietary.
No proprietary information was identified.
ATTACHMENT
SUPPLEMENTAL INFORMATION
PARTIALLIST OF PERSONS CONTACTED
Licensee
J. R. Becker, Manager, Operations Services
W. G. Crockett, Manager, Nuclear Quality Services
R. D. Gray, Director, Radiation Protection
T. L. Grebel, Director, Regulatory Services
D. B. Miklush, Manager, Engineering Services
D. H. Oatley, Vice President and Plant Manager
R. A. Waltos, Manager, Maintenance Services
L. F. Womack, Vice President, Nuclear Technical Services
INSPECTION PROCEDURES (IP) USED
IP 6-1 726
IP 71707
IP 92700
IP 92903
Onsite Engineering
Surveillance Observations
Maintenance Observation
Plant Operations
Plant Support Activities
Onsite Follow up of Written Reports of Nonroutine Events at Power
Reactor Facilities
Follow up - Maintenance
Follow up - Engineering
ITEMS OPENED AND CLOSED
~Oened
None.
Closed
50-323/97-005-00
LER
Reactor trip and safety injection caused by inadvertent main
steam isolation valve closure because of personnel error
(Section M8.1)
50-275; 323/
97-003-01
IFI
Periodic testing requirements for main feedwater pump
turbine stop valves (Section E8.1)
50-275/97-012-00
50-275; 323/
97-003-00
LER
TSs 3.7.3.1 and 4.0.5 not met because
of personnel error
(Section E8.2)
LER
Reactor vessel level indication system outside design basis
(Section E8.3)
0 ened and Closed
50-275/99006-01
50-275/99006-02
Failure to properly implement the inservice testing program
for a component cooling water pump (Section E8.2)
Two examples of failure to followadministrative procedures
'Section F1.1)
i
LIST OF ACRONYMS USED
IFI
IP
LER
NRC
TS
American Society of Mechanical Engineers
action request
component cooling water
inspection followup item
inspection procedure
licensee event report
noncited violation
Nuclear Regulatory Commission
Public Document Room
Technical Specification
)
I