IR 05000301/1993016
| ML20058E166 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 11/24/1993 |
| From: | Jeffrey Jacobson, Schaper J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML20058E164 | List: |
| References | |
| 50-301-93-16, NUDOCS 9312060196 | |
| Download: ML20058E166 (5) | |
Text
.
-
.
.
.
-
,
U. S. NUCLEAR REGULATORY COMMISSION REGION 111
<
Report No. 50-301/93016(DRS)
i Docket No. 50-301 License No. DPR-27 Licensee:
Wisconsin Electric Power Company
[
231 West Michigan - P379
!
Milwaukee, WI 53201 facility Name: Point Beach Nuclear Plant - Unit 2 Inspection At: Two Rivers, WI 54241 l
Inspection Cond ted: October 12-14, and November 10, 1993
)
Inspector:
3d
///23/9
'
s i F. Schapker Date
{\\li
/\\
'
Approved By-d#s t We
/ + e t7
(
J. ly escobson, Chief Date s
Mattria[s and Processes Section
.v b
i inspection Summary
,
i
!
Inspection on October 12-14. and November 10. 1993 (Recort No.
!
50-301/93016(DRS))
Areas Insoected:
Routine unannounced inspection of inservice inspection (ISI)
activities including review of program (73051), procedures (73052),
observation of work activities (73753), data review and evaluation (73755),
and review of the erosion / corrosion program (49001).
Results: Of the areas inspected, no violations or deviations were identified.
During the course of the inspection, the following were noted:
Based on the areas reviewed, the licensee appears to have an effective 151 program. The licensee contracts for some ISI services and performs 151 activities to ASME Section XI requirements, utilizing state of the art ISI equipment and procedures.
The erosion / corrosion program is in the process of being upgraded to utilize EPRI's CHEC NDE program.
The licensee requested EPRI to provide assistance in revising the program. The EPRI report provided suggestions to enhance the effectiveness of the program and necessary guidance to assure the effective application of CHEC NDE. The licensee's efforts to improve the E/C program is considered a strength.
The licensee customized the eddy current Data Analysis Guidelines to reflect the inspection history of the individual unit.
As a result, i
,
enhanced guidance was provided in the interpretation of signals.
The revised guidelines were considered to be a significant improvement.
9312060196 931124 PDR ADOCK 05000301 g
_.
.
.
..
.
--
.-
i
..
. _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
.
.
.
.
,
i
!
\\
DETAILS
'
I.
Persons Contacted
,
Wisconsin t'lectric Power Company (WEPCo)
j
- G. Maxfield, Plant Manager
- J. Becka, Manager, Regulatory Services i
T. Staskal, Senior Project Engineer
- K. Crowley, Senior Engineer, Performance Engineering
- C. Prothero, Senior Engineer, Performance Engineering
- F. Fleutje, Regulatory Administrative Specialist
'
J. Michaelson, Quality Assurance Supervisor
,
- J. Brander, ISI Specialist
'
- J. Valentine, ISI Engineer i
Hartford Steam Boiler Enaineerino and insurance Company (HSB)
I r
j J. Gault, ANII
'
i Westinghouse Electric Corporation (WEC)
i i
D. Obuzenu, Level III Eddy Current Examiner i
U. S. Nuclear Reaulatory Commission (NRC)
- K. Jury, Senior Resident Inspector l
J. Gadzala, Resident Inspector
!
- Denotes those attending the exit meeting on November 10, 1993.
t Other licensee and contractor personnel were contacted during the course of this inspection.
2.
Inservice inspection Review of olan (73051)
The NRC inspector reviewed the third ten-year inservice inspection a.
(ISI) plan, first period, second outage. The ISI plan conformed to the requirements of ASME Section XI, 1986 Edition.
Relief requests in accordance with 10CFR50.55A (G)(5)(IV) had been i
applied for by the licensee.
The services of an Authorized Nuclear Inservice Inspector (ANII) were procured and the ISI procedures, inspection reports, and personnel certifications were reviewed by the ANII.
The licensee contracted EBASCO Services, Inc. and Professional Welding Associates to assist the WEPCo Quality Assurance Department in performing the ISI. Westinghouse Electric Company (WEC) was contracted to perform eddy current examination (ET) of the steam generator tubing.
,
I
I
-
.
.
.
.
.
b.
ISI Documentation Review (737551
'
i The NRC inspector reviewed documents relating to the following:
Nondestructive examination (NDE) procedures utilized for j
ISI.
- NDE personnel certifications in accordance with Stvi-TC-1 A.
NDE examination reports.
Ultrasonic examination (UT), liquid penetrant examination (PT), and radiograph data reports for the pressurizar safety nozzles.
i l
ET examination data and graphic reports.
\\
ET data analysis guidelines.
Documentation reviewed complied with the ASME Section XI, 1986
!
Edition requirements.
t c.
Observation of Work Activities (737531 j
The NRC inspector observed the following work activities in
'
progress:
l ET examination of steam generator tubes.
l Radiograph review of pressurizer safety nozzles.
Work activities were performed in accordance with approved
!
procedures, utilizing calibrated NDE equipment, and certified i
personnel. Detection and evaluation of flaws were completed in
'
accordance with the ASME Code and regulatary requirements.
i 3.
Eddy Current Examination of Unit 2 Steam Generator Tubes (73753. 73755)
!
a.
General Point Beach, Unit 2, utilizes Westinghouse model 44 SGs.
The
!
licensee had previously performed prever.tive sleeving of
.
approximately 46% of the tubes due to degradation (IGA /lGSCC) in
'
the tubesheet crevices and plans to replace the SGs in the near future. The licensee's ET program appeared to be conservative in l
assuring the safe operation of the SG's for Unit 2.
The licensee
'
completed the five year EPRI recommended sampling schedule for tube examinations this outage.
The licensee employed WEC to perform ET of the SG tubes.
Inspection of the SG tubes included:
,
.
-.
-
.
.
-.
-
-
-
.
.-.
. -...
.
,
.
.
-
-
,
full-length inspection of 2915 A" SG tubes and 2938 "B" SG
'
tubes using the bobbin coil probe.
350 sleeves in the "A" SG, and 474 in the
"B" SG were examined using the bobbin coil probe.
Motorized rotating pancake coil {MRPC) of distorted
'
indications included 65 intersections in "A" SG, and 57 intersections in the "B" SG.
Examination results showed most of the indications were attributed
'
to corrosion degradation due to primary water stress corrosion cracking (PWSCC) at the 140t leg ro i transition.
The tube support plates in both hot and cold legs and the hot leg tubesheet crevices have experienced degradation due to IGA and IGSCC.
!
l The "A" SG had 115 tubes with indications, of which 45 were
.'
t degraded (20-39%) and 21 were defective (>40%).
The "B" SG had
'
162 tubes with indications, of which 91 were degraded and 12 were
>
l defective. All defective tubes were plugged.
Both primary and secondary data analyses were performed at the Westinghouse Remote Data Analysis Center at the Waltz Mill site in Madison, Pennsylvania, with only resolution analyst data managers i
'
at the Point Beach site.
l Data collection and analysis met the requirements of the ASME 1986
!
Section XI, IWA-3200 and mandatory requirements of Appendix IV.
b.
Inspection The NRC inspector observed ET of the SG tubes in progress,
verified calibration / certification of ET equipment and calibration standards, and reviewed the examiners / analyst qualification certifications. The NRC inspector also reviewed the ET Data Analyst Guidelines for Unit 2 SGs, and reviewed a sample of ET graphics for indication resolution.
j The licensee's ET program and tube degradation preventive maintenance program is acceptable.
The bobbin coil is presently used to inspect the roll transition region.
The procedure requires that distorted bobbin coil signals in this region be inspected with MRPC. Based on industry experience, the tube roll transition regions are known to be susceptible to circumferential cracking. The bobbin coil is relatively insensitive to i
circumferential cracks, unless the crack has a significant axial component.
Industry experience has shown that some i
circumferential cracks have too small of an axial component to be detected by the bobbin coil, even as a distorted signal.
i
.
.
. ~
.
.
.
.
-
Although no circumferential cracks were detected during this inspection at the roll transition region, the Unit 2 SGs have indications of PWSCC in this region. A sample inspection of the sleeve region and roll transition area using tiRPC would enhance future SG tube examinations.
Review of the revised Data Analysis Guidelines showed significant improvement from the previous guidelines which included both Point Beach Units 1 and 2 as one. The revised edition segregates the units and identifies the significant differences and inspection history. The new guidelines should aid the data analyst in the evaluation of eddy current signals.
4.
Erosion / Corrosion Monitorino Activities (49001)
The licensee's erosion / corrosion (E/C) program is currently in the
'
process of being revised to implement the Chec NDE program.
Prior to
,
the outage, the licensee requested onsite assistance from EPRI to:
'
Review the scope and methods used for implementing the E/C program I
and to suggest ways in which the program might be improved.
r Provide assistance in addressing modeling issues related to the
!
use of EPRI's Checmate and Chec NDE computer codes.
j
,
Identify ways in which the codes and related methodologies could
be enhanced based on the licensee's experiences.
The EPRI visit was not an independent review or audit, but provided
i irrportant guidance in the implementation of the licensee's E/C program.
The licensee indicated that the suggested improvements are being implemented into the program.
The NRC inspector reviewed the EPRI draft report for the above
!
referenced EPRI visit. The suggested program improvements will
substantially improve the current E/C program and provide additional conservatism to assure E/C is identified and corrected.
i j
l No violations or deviations were identified.
5.
Exit Interview The NRC inspector met with the licensee representatives (denoted in l
Section 1) at the conclusion of the inspection on November 10, 1993.
j The inspector summarized the purpose and findings of the inspection.
The licensee representatives acknowledged this information. The inspector also discussed the likely informational content of the I
inspection report with regard to dc;.uments or processes reviewed during the inspection. The licensee representatives did not identify any such documents or processes as proprietary.
]
_
_.
.
_
_
-
4