ML16342D656
| ML16342D656 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 05/19/1997 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | |
| Shared Package | |
| ML16342D657 | List: |
| References | |
| 50-275-97-05, 50-275-97-5, 50-323-97-05, 50-323-97-5, NUDOCS 9705230208 | |
| Download: ML16342D656 (16) | |
See also: IR 05000275/1997005
Text
ENCLOSURE
U.S. NUCLEAR REGULATORY COMMISSION
REGION IV
Docket Nos.:
License Nos.:
Report No.:
Licensee:
Facility:
Location:
Dates:
Inspector:
Approved By:
50-275
50-323
DPR-82
50-275/97-05
50-323/97-05
Pacific Gas and Electric Company
Diablo Canyon Nuclear Power Plant, Units
1 and 2
7 1/2 miles NW of Avila Beach
Avila Beach, California
April 21-24, 1997
Paul C. Gage, Reactor Inspector, Maintenance
Branch
Dr. Dale A. Powers, Chief, Maintenance
Branch
Division of Reactor Safety
ATTACHMENT:
Supplemental
Information
9705230208
970519
ADQCK 05000275
8
-2-
EXECUTIVE SUMMARY
Diablo Canyon Nuclear Power Plant, Units
1 and 2
NRC Inspection Report 50-275/97-05; 50-323/97-05
This inspection consisted of a review of the licensee's
planned and implemented activities
associated
with the inservice inspection program.
The inspection report covers
a 4-day
period onsite by one region-based
inspector.
Maintenance
Nondestructive examinatiqns
were performed in a professional
and thorough
manner.
Examiners were experienced
and knowledgeable
of their assigned
tasks
(Section M1.1).
The inservice inspection procedures
contained sufficient detail and instructions to
perform the applicable nondestructive
examinations
and were consistent with the
requirements
of the American Standard
Mechanical Engineers
Code (Section M3.1).
were performed by appropriately certified individuals in
accordance
with approved procedures
(Sections M5 ~ 1).
-3-
Re ort Details
Summar
of Plant Status
During this inspection period, Unit
1 was in Mode 5 for Refueling Outage 1R08, while
Unit 2 was at 100 percent power.
II. IVlaintenance
M1
Conduct of Maintenance
M1
~ 1
Nondestructive
Examination Observations
a.
Ins ection Sco
e 73753
The inspector observed the performance of an ultrasonic examination and a liquid
penetrant examination on a Class 2 weld on a 3-inch stainless steel pipe.
These
examinations
related to the chemical and volume control system design change that
routed the normal charging system connection upstream of the flow element in the
reactor coolant pump seal injection line. The inspector also reviewed the certified
material test reports of the penetrant,
cleaner, and developer materials.
The
inspector monitored the processes
involved in the automated
ultrasonic examination
of the feedwater nozzle weld on Steam Generator 1-1.
b.
Observations
and Findin s
The inspector verified that approved Procedure
N-PT-1, "Solvent Removable Visible
Dye Liquid Penetrant
Examination. Procedure,"
Revision 6, was followed while
performing required nondestructive
examinations
involving the chemical and volume
control system design change.
The inspector noted that the chloride and halogen
limitations had not been exceeded.
The inspector observed that the nondestructive
examination examiners verified the surface temperature
of the welds were within
the minimum and maximum procedural requirements,
and all observed work was
performed with the work package present and in active use.
During the conduct of the liquid penetrant examination, the inspector observed that
the designated
Class 2 pipe was not identified as safety-related
material.
Such
identification was required in accordance
with Administrative Procedure
CF5.ID2,
"Control of Material in Storag," Revision 2.
Procedure MA3.ID1, "Nondestructive
Examination Program," Revision 1, required that, if problems were discovered, the
examiners were to identify them and initiate resolution.
The inspector noted that
problems, which can be corrected in process,
were not required to be handled in
accordance
with Procedure
OM7.ID1, "Problem Identification and Resolutions-
Action Requests,"
Revision 7.
The licensee's
personnel,
without inspector
prompting, identified the discrepancy
and took immediate actions to correctly
identify the pipe with a safety-related
material sign.
Before the ultrasonic examinations were conducted,
the inspector observed the
system calibration, which included both axial and circumferential scans.
The
transducer selection, sensitivity calibration, and construction of the distance
amplitude correction curve were performed in accordance
with the associated
procedure.
The inspector verified that the correct calibration blocks were used (i.e.,
they were similar to the components
to be examined
in terms of material, diameter,
and wall thickness).
The nondestructive'xamination
examiners documented
their
calibration and examination results of all pertinent information specified by the
procedure.
The inspector noted that the ultrasonic examination of the
circumferential pipe weld was conducted with a shear wave mode (45-degree
angle
beam) in two directions (perpendicular
and parallel to the weld axis) using
a
transducer with a frequency of 2.25 Hz. The inspector verified that designated
Procedure
N-UT-1, "Ultrasonic Examination Procedure
For Pipe Weids," Revision 10,
had been approved
and was being followed.
The inspector also observed the
examiner perform a calibration check at the beginning of the examination.
Discussions with the examiners performing the ultrasonic and liquid penetrant
examinations
indicated that they were experienced
and knowledgeable
nondestructive
examination personnel.
They were cognizant of the procedural
and
documentation
requirements,
and understood
the examination techniques.
The examinations of the steam generator welds were performed using 0, 30, and
~
45 degree longitudinal wave modes in accordance
with Procedure
N-UT-B,
"Automated Ultrasonic Data Acquisition and Analysis Procedure,"
Revision 5.
The
inspector noted that the automated
ultrasonic technique utilized a non-Class A
software system for the acquiring, processing,
and displaying information for the
examiner to determine acceptable
weld configurations, including Class
1 welds.
The inspector verified that the implementation of the VIPER software system
was
performed through quality-related Procedure
CF2.TE1, "TES Software Quality
Assurance
Program," Revision 0. The inspector noted that the automated
ultrasonic
procedure
required adequate
calibration and linearity checks of the system including
the sensors,
software, and subsequent
displayed output.
II
0
-5-
The inspector noted that the definition of a Class A cc mputer system was
delineated
in Procedure
CF2.ID2, "Software Quality Assurance for Computer
Systems,"
Revision 1. The definition included a system that directly supports
Technical Specifications,
or an analysis system used directly for safety-related
plant
systems.
The inspector found the definition to be appropriate.
The inspector determined that the software utilized by the automated
ultrasonic
technique was not classified as Class A. The licensee staff noted that Procedure
CF2.ID2 exempted computer systems
used to manage information for the
convenience
of the user, provided the user fully accepted
responsibility for the
results, established
and implemented procedural controls for quality-related
activities, and assured that alternate means of demonstrating
validity were in place
(periodic calibration of a measuring system).
The inspector determined that the
licensee subjected the VIPER software system to a less detailed verification and
validation than expected for a Class A software designation.
The inspector found
that the implementation process utilized by the licensee regarding the automated
ultrasonic examination to be nonconservative.
Although this approach
did not
violate any regulatory requirements,
the issue was discussed
with the licensee's
staff for action as they. deem appropriate..
c.
Conclusions
The observed
examinations were performed in a professional
and thorough manner.
Examiners were experienced
and knowledgeable
of their assigned
tasks.
IVI3
Maintenance Procedures
and Documentation
M3.1 Inservice Ins ection Pro ram Plan and Procedures
73753
a.
Ins ection Sco
e 73753
The inspector reviewed the licensee's
inservice inspection plan and schedule for the
current inspection interval to determine if changes
to the inspection plan concerning
component selection, etc., have been properly documented
and approved.
The
inspector also reviewed the licensee's
inservice inspection procedures.
The
inspector reviewed Revision 0 of the licensee's
inservice inspection program plan
(dated November 19, 1996) for the second
10-year inspection interval for Diablo
Canyon Powe~ Plant, Unit 1. The inspector reviewed the nondestructive
examination procedures
used during the observed examinations to verify that they
were consistent with the requirements
of Section XI of the ASME Code, 1989
Edition, without Addenda.
-6-
b.
Observations
and Findin s
The inspector noted that the NRC was in the process of reviewing and
evaluating the licensee's submitted inspection plan to determine compliance
with 10 CFR 50.55a(g).
As documented
in Section 5.2.8 of the Final Safety
Analysis Report, the ASME Boiler and Pressure
Vessel Code,Section XI, 1989
Edition without addenda,
was used as the basis for the inservice inspection
program.
An NRC letter dated March 12, 1997, documented
a request for
additional information regarding the licensee's submittal of the current inservice
inspection program plan and associated
requests for relief from the ASME Boiler and
Pressure
Vessel Code,Section XI requirements.
The inservice inspection program plan described the ASME Code Class
1, 2, and 3
components
subject to surface, volumetric, and visual examinations,
and included
NRC-approved requests for relief for each item where the licensee determined that a
code-required
examination was not practical
~ Tables in the program plan identified
the name of the component
or system, code class, item number, and general
identification.
Also included were the required nondestructive
examination methods
and applicable remarks or references to requests for relief that have been approved.
The procedures
were found to be well written, and they contained sufficient detail
and instructions to perform the intended examinations.
C.
Conclusion
Nondestructive examination procedures
were well written and provided sufficient
detail to support the performance of the inservice inspection program plan.
IVI5
Maintenance Staff Training and Qualification
M5.1 Personnel
Qualification and Certification
a o
Ins ection Sco
e 73753
The inspector reviewed the qualifications and certifications of the inspection
personnel
involved with the inservice inspection program.
The inspector reviewed
Procedure
2.1, "Qualifications and Certifications of Personnel,"
Revision 8, to verify
that the certification process met the requirements of American Society for
Nondestructive Testing's "Recommended
Practice SNT-TC-1A," 1984 Edition.
The
inspector reviewed the applicable qualification files of four nondestructive
examination Level II examin=rs and all the Level III examiners.
-7-
b.
Observations
and Findin
s
The licensee representative
informed the inspector that the performance of some of
inservice inspection examinations
were contracted out, but were performed by
nondestructive
examination examiners who were certified by the licensee.
The
inspector observed that the inservice inspection supervisor exhibited a high degree
of competency,
was fully cognizant of ASME code requirements
and inservice
inspection program commitments.
The inspector noted that the reviewed
qualification and certification files contained the appropriate examinations
and
certifications for the designated
nondestructive
examination methods.
The records
showed that the personnel
had been certified in accordance
with the 1984 Edition
of SNT-TC-1A. As required by the ASME code, all of the individuals had maintained
current documentation
regarding near-distance
acuity and color vision examinations.
c.
Conclusion
The nondestructive
examinations
were performed by knowledgeable
and
appropriately certified individuals in accordance
with approved procedures.
X1
Exit Meeting Summary
The inspector presented
the inspection results to members of licensee management
at the conclusion of the inspection on April 24, 1997.
The licensee personnel
acknowledged
the findings presented.
The inspector asked the licensee personnel whether any materials examined during
the inspection should be considered
proprietary.
No proprietary information was
identified.
C
'
ATTACHMENT
SUPPLEMENTAL INFORMATION
PARTIAL LIST OF PERSONS CONTACTED
Licensee
D. Adamson, Level III Examiner, Technical and Environmental Services Nondestructive
Examinations
K. Bych, Director, Nuclear Quality Services Maintenance
W. Crockett, Manager, Nuclear Quality Services
D. Gonzalez, Supervisor,
Inservice Inspection
H. Karner, Auditor, Nuclear Quality Services Maintenance
S. LaForce, Engineer, Regulatory Services
R. Martin, Engineer, Regulatory Services
F. Sattler, Auditor, Nuclear Quality Services Maintenance
D. Taggart,'Director, Nuclear Quality Services
D. Vosberg, Director, Nuclear Steam Supply Systems
NRC
D. Allen, Resident Inspector
M. Tschiltz, Senior Resident Inspector
INSPECTION PROCEDURES USED
ll
Inservice Inspection