ML20024F572

Final Deficiency Rept Re Deformed Wire Anchors Separated from Embedded Plate.Initially Reported on 821020.Results of Tests Indicated Cause Due to Axial Tensile Stress Applied to Welds.Item Not Reportable Per 10CFR50.55(e)

ML20024F572
Person / Time
Site:	Marble Hill
Issue date:	08/30/1983
From:	Shields S PSI ENERGY, INC. A/K/A PUBLIC SERVICE CO. OF INDIANA
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
10CFR-050.55E, 10CFR-50.55E, S82-25, SVP-0123-83, SVP-123-83, NUDOCS 8309090483
Download: ML20024F572 (2)

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PUBLIC SERVICE INDIANA S. W. Shields August 30, 1983 senior vice President - S82-25 Nuclear Division SVP-0123-83 Mr. James G. Keppler, Docket Nos.: STN 50-546 Regional Administrator STN 50-547 U. S. Nuclear Regulatory Commission Construction Permit Nos.:

Region III CPPR - 170 799 Roosevelt Road CPPR - 171 Glen Ellyn, Illinois 60137 Marble Hill Nuclear Generating Station - Units 1 and 2

Dear Mr. Keppler:

On October 20, 1982, Mr. T. D. Geib of Public Service Company of Indiana, Inc. (PSI) notified your of fice of a potentially reportable item as required by 10 CFR 50.55(e). During repair of spalled concrete around an embedded plate in the Unit 1 containment, deformed wire anchors were discovered to have separated from the plate. This item varies from that identified on August 18, 1982 (S82-21), since this embedded plate was installed after the resunption of safety related work at Marble Hill.

Tests performed by an independent laboratory to determine the failure mode of the cracked welds have been completed and the results analyzed.

The results of these tests indicate that an axial tensile stress applied to the welds was the primary cause of failure. This stress was developed due to the excessive heat buildup during the process of welding box beams to the embedded plates. This welding method was later changed for similar welds on Unit 2 to prevent cracking or breaking the anchors.

. PSI's architect engineer, Sargent & Lundy, has performed an evaluation of embedded plates with deformed wire anchors on which heavy box beam collars have been welded in the Unit 1 containment and has found those embedded plates to be adequate to support the Marble Hill design loads.

The evaluation was performed utilizing the as-built lecations of the box beam collars on the embedded plates as submitted by the primary

. civil contractor, Newberg-Marble Hill, and assuming that all anchors directly beneath the weld joining the box beam collar to the embedded plate have separated from the plate. Considering that the embedded plates on which anchors were exposed pursuant to Newberg-Marble Hill g NCR 4821, showed that no plate exhibited separation of all the anchors p[\ h 8309090483 830830

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PDR ADOCK 05000546 SEP 2 1983 S PDR P. O. Box 190, New Washington, Indiana 47162 812 . 289 . 3000

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l pOBUC SEIVJLCE INDIANA August 30, 1983 Letter: 3* G* Keppler _2 S82-25 SVP-0123-83 beneath the box beam collar weld, this assumption is conservative.

The reduced embedded plate capacities were then compared to design loads obtained from a detailed time history seismic analysis to determine acceptability.

Based on the above information, PSI has determined this item not reportable under the provisions defined in 10 CFR 50.55(e). If you have any questions regarding this matter, please contact me at your convenience.

Sincerely,

/

S. W. Shields SWS/LGY/bak cc: Director of Inspection and Enforcement U. S. Nuclear Regulatory Commission Washington, D. C. 20555 J. E. Konklin J. F. Schapkcr

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