ML18054B501
| ML18054B501 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 03/01/1990 |
| From: | Danielson D, Schapker J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML18054B499 | List: |
| References | |
| 50-255-90-08, 50-255-90-8, NUDOCS 9003200163 | |
| Download: ML18054B501 (4) | |
See also: IR 05000255/1990008
Text
U. S. NUCLEAR REGULATORY COMMISSION
REGION III
Report No.
50~255/90008(DRS)
Docket No. 50-255 -
Licensee:
Consumers Power Company
1945 West Parnall Road
Jackson, Michigan 49201
Facility Name:
Palisades Nuclear Generating Plant
Inspection At:
Palisades Site, Covert, MI.-
Inspection Conducted:
February 21, 1990
.. /~.
/
.
Inspector:
Ii
~~
D. H. Danielson, Chief
Materials and Processes Section
Inspection Summary
License No. DPR-20
Dat~ . I
Date
Inspection on February 21, 1990 (Report No. 50-255/90008(DRS))
Areas Inspected: Routine unannounced inspection of licensee action in response
to previously identified inspection findings (92702).
Results:
Of the areas inspected, one deviation was identified for incomplete
corrective action taken as described in the licensee's response to violation
255/88022-01.
The NRC inspector noted the following:
0
The licensee's engin~ering justification for not performing the cold leg
scans appeared to be adequate.
However, the licensee did not inform the
NRC of the deviation from commitments made for corrective
action to violation 50-255/88022-01.
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DETAILS
1.
Persons Contacted
Consumers Power Company (CPCo)
- C. S. Kozup, Technical Engineer
K. V. Cedarquist, Senior Engineer
U~ S. Nuclear Regulatory Commission (U. S. NRC)
E. R. Swanson, Senior Resident Inspector
J. K. Heller, Resident Inspector
Other members of the plant staff were also contacted.
- Denotes those present *at the exit interview.
2.
Licensee Action on Previously Identified Inspection Findings (92702)
(Closed) Violation (255)88022-01) Inade~uate quality verification
resulting in misplugged or defective tu e plugs in steam generators (SG)
a.
Background
Numerous discrepancies with respect to tube plugging have been
identified since 1983.
Included are misplugged tubes, defective
plug welds and incomplete plug welds.
The licensee's quality verification process appeared inadequate to
assure that these deficiencies were identified and corrected.
As
part of the licensee's commitment to assure that all misplugged tubes
had been identified and corrected, the licensee committed to review .
exlsting video tapes of the tube sheet. If the video tape review was
inadequate to assure that the tube plugging was performed correctly,
a 100% tube sheet verification via video camera in both
11A
11 and
118
11
steam generators was to be conducted.
During the last outage, the licensee performed visual scans of the
hot leg tubesheets of steam generators
11A
11 and
118
11 *
Results of this
scan found no misplugged tubes but identification of a drawing error
disclosed that two tubes were incorrectly indicated as being plugged.
Review of the plugged tube list indicated the tubes were not required
to be plugged.
The drawing was.subsequently corrected. Cold leg
visual scans for leakage only were performed, but they did not
involve inspection for misplugged tubes as the licensee had not
planned to perform inspections on the cold legs of the steam generators.
The NRC inspector informed the licensee at the exit meeting on
December 9, 1989 (reference NRC Inspection Report No. 50-255/89032(DRS),
that corrective actions reviewed for this violation appeared inadequate
and did not meet the corrective action commitments made in their
. response dated February 16, 1989.
2
The licensee*s inservice inspection (ISi) supervisor informed the NRC
inspector that Consumers Power Company had performed a review of the
cold l~gs of the "A" and "B" steam generators via video tapes from
- previous outages and confirmed that no misplugged tubes existed in
the cold legs. However, no documentation was produced to verify that
this.action was completed and the corrective action documents did not
reference this review.
The licensee agreed to provide the documentation for the NRC
inspector
1s review.
Consequently, the NRC inspector informed the
licensee the violation would remain open pending review of corrective
action documentation.
b.
- Inspection
The NRC inspector reviewed the licensee*s additional response to NRC
Inspection Report No~ 50-255/88022-01 in a letter dated February 9, 1990. ~
The licensee*s response states that cold l~g side video tapes of the
1983, 1985, and 1987 plugged tubes were reviewed and all tubes
plugged during those outages were verified as correct except for 16
tubes in the "A" steam generator and 12 tubes in the ~B" steam
generator which could not be confirmed due to insufficient video.
The licensee made the decision not to perform a 100% video verification
of the
11A
11 and
118
11 steam generator cold legs because of the following:
(1)
No misplugged tubes were identified in the hot leg scans.
(2)
No discrepancies were noted in the review of the video tapes
of the 1983, 1985, and 1987 plugged tubes in the cold legs.
(3)
The close proximity cf the Palisades steam generator
replacement.
(4)
The large man-rem exposure required versus the additional
assurance gained.
The NRC inspector reviewed documentation which *indicated that the
licensee had performed reviews of the video tapes which confirmed
correct plugging with the exception of those areas where video
quality or obstruction prevented confirmation. These reviews were
made in the Fall of 1988 and the results were reported in September
1988.
The licensee decided not to perform visual scans on the cold
legs of the steam generators because they had not planned to enter
the cold legs during the outage. However, as reported in NRC
Inspection Report No. 50-255/89032(DRS), entry was made and leaking
tubes were found in steam generator
11A
11 and eddy current examination
(ET) disclosed additional cracked tubes in the cold legs of steam
generators
11A
11 and "B".
The licensee entered the cold legs and
performed ET.with the opportunity to verify the 16 tubes in steam
generator
11A" and 12 tubes in steam generator "B" at a minimal of
man-rem exposure and expense.
3
The NRC inspector agrees the entry into the cold leg side to perform
the visual inspection for 28 tube plugs would not be warranted for
the reasons the licensee cited in their* letter of February 9, 1990."
The probability of a misplugged tube existing in either of these
steam generators is remote.
The "A" steam generator cold leg has
a total of 2,044 ttibe plugs with only 16 tube plugs not verified ~nd
"B" steam generator has 2,442 tube plugs with only 12 which were
not verified. However, cold leg entry was made, and therefore,
reduces the rationale for not performing a remote visual scan of the
28 tubes not previously verified. The NRC inspector does not
believe it is prudent for the licensee to be required to inspect
these tube plugs at this time due to the following:
(1} . The plant operational statu~.
(2) The near-term replacement of thesteam generators.
(3)
Leak before break analysis (tube leakage prior to failure).
(4)
The administratively reduced leak rate requirement (.1 gpm over
a 24-hour period).
(5) The large man-rem exposure required to perform the inspection
at this time.
However, the licensee deviated from their cormnitment as stated in
the response to violation 255/88022-01 without consulting the ~RC
(Reference: Consumers Power Company response dated February 16, 1989,
to the Notice of Violation presented in Inspection Report No.
50-255/88022).
The licensee's corrective action taken in response to
violation 255/88022-01 demonstrates a lack of management oversight to
assure the connnitments made to the NRC are met; this is a deviation
(255/90008-01).
.
No violatioris were identified and one deviation was disclosed as
referenced in the above section of this report.
3. . Exit Meeting
The NRC inspector contacted Mr. c *. Kozup by telecon on February 26, 1990,
. and summarized the scope and findings of the inspection activities. The
licensee acknowledged the inspection findings.
The inspector also
discussed the likely informational content of the inspection report with
regard to documents or processes reviewed by the inspector. The licensee
did not identify any such documents/processes as proprietary.
4