ML19207B977

First Interim Deficiency Rept Re Containment Anchor Bolt Chain Weld Deficiencies.Caused by Breakdown in Institution of Welding Qa/Qc Program Due to Misunderstanding of Weld Acceptance Criteria by Some Inspectors

ML19207B977
Person / Time
Site:	Hartsville
Issue date:	08/30/1979
From:	TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML19207B969	List: ML19207B968 ML19207B977
References
NCR-HNP-A-062, NCR-HNP-A-62, NUDOCS 7909060264
Download: ML19207B977 (2)

Text

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ENCLOSURE HARTSVILLE NUCLEAR iLANT UNITS Al AND B1 CONTAINMENT ANCHOR BOLT CHAIR WELD DEFICIENCIES 10CFR50.55(e) REPORT NO. 1 (INTERIM)

NCR EXP-A-062 On August 2, 1979, TVA notified NRC-0IE Region II, Inspector F. S. Cantrell, of a potentially repo-table condition under 10CFR50.55(e) regarding deficient welds between the containment anchor bolt chair (stiffener plate) and both the containment shell and the containment base plate. This is the first report on the subject reportable condition. The final report will be submitted on or before January 11, 1980.

Description o f Deficiency During the course of investigating items concerning quality contrcl investi-gation reports (QCIR's) on containment anchor bolt chair welds for unit B1, a welding QC group leader noticed cther unacceptable welds between containment anchor bolt chairs and the contaimtent shell and/or the containment base plate. Further investigations by the TVA Welding QC Unit group leader who discovered the problem identified additional unacceptable welds on some of the 900 chair plates on units Al and Bl. These welds had been inspected and signed off by QC welding inspectors (hereinafter referred to as inspectors) as acceptable even though they did not meet the acceptance requirements of QCI N501 and N201 with respect to either weld size, undercut, surface condition, or a combination of the three This deficienc5 is a combination of a breakdown in implementation of the welding QA/QC program and the existence of the unacceptable welds.

At this point it is not known exactly how many welding inspectors are involved. That information will be available at the time of the final report.

Cause of the Deficiency The deficiency is and resulted from a breakdown in implementation of the TVA welding QA/QC program in which some inspectors were allowing wells which did not meet specification requirements to pass inspection. Th s situation appears to have resulted from incomplete understanding on the part of some inspectors as to weld acceptance criteria and not from intentional disregard of acceptance criteria by the inspectors.

Safety Implications Safety implications will be discussed in the final report.

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Corrective Action As a result of this deficiency, TVA has undertaken an extensive investigation of welds that had been previously accepted by the inspectors who passed unacceptable welds on the containment anchor bolt chairs. TVA will correlate the results of this investigation with patterns of acceptance of deficient welds for individual inspectors. In this way TVA will be able to determine appropriate retraining. Also, unacceptable welds found as a result of this deficiency and the investigations thereof will be corrected to comply with applicable requirements.

To date this problem has been discussed with all welding QC inspectors.

The QC welding inspectors who passed unacceptable welds are in the process cf retraining and recertification with particular emphesis placed on weld acceptance criteria of the applicable specification.

Action Taken to Prevent Recurrence This item will be discussed in the final report.

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