ML19224D474
| ML19224D474 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 06/21/1979 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Bryan J UNION ELECTRIC CO. |
| References | |
| NUDOCS 7907120262 | |
| Download: ML19224D474 (1) | |
Text
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o UNITED STATES E'
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NUCLEAR REGULATORY COMMISSION TIb
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REGION lli J'f 799 AOOSEVELT ROAD o,
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0 GLEN ELLYN, ILLINOIS 60137 0
JUN 211979 Docket No. 50-483 Docket No. 50-486 Union Electric Company ATTN:
Mr. John K. Bryan Vice President - Nuclear P. O. Box 149 St. Louis, MO 63166 Gentlemen:
Enclosed is IE Bulletin No. 79-02 Revision No.
1, which requires action by you with regard to your power reactor facility with an operating license or a construction permit.
Should you have any questions r garding this Bulletin or the actions required by you, please contact this office.
Sincerely, h
/gtJamesG.Keppler C-Director Enclo ure:
IE Bulletin No. 79-02 Revision No. I cc w/ encl:
Mr. W. H. Webe r, Manage r,
Nuclear Construction Central Files Director, NRR/DPM Director, NRR/ DOR FDR Loes.1 PDR
%!C TIC Region I & IV hs. K. Drey Hon. C. J. Frass, Chairman 11issouri Public Service Commission 327 008 7 0 07120 2 (>R
- n U.S. NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT RECION III June 21, 1979 IE Bulletin No. 79-02 (Revision No. 1)
(7906200183)
PIPE SUPPORT BASE PLATE DESIGNS USING CONCRETE EXPANSION ANCHOR BOLTS Description of Circumstances:
Since the issuance of IE Bulletin 79-02 on March 8, 1979, IE inspection experience and many inquiries from liceusees indicate that additional informa-tion and larification is needed.
This revision is intended to serve that purpose. None of the requirements of the original Bulletin have been deleted, and the due date for completion of the requested actions (July 6, 1979) has not been changed. The following text supercedes the text of Bulletin 79-02.
Changes from the original text are identified by lines in the margin. The purpose of this revision is to identify acceptable ways of satisfying the Bulletin requirements.
While performing inservice inspections during a March-April.178 refueling outage at Millstone Unit 1, structural f,ilures of piping supports for safety equipment were observed by the licensee.
Subsequent licensee inspections of undamaged supports showed a large percentage of the concrete anchor bolts were not tightened properly.
Deficiency reports, in accordance vith 10 CFR 50.55(e) filed by Long Island Lighting Company on Shoreham Unit 1, indicat e +'..at design of base plates using rigid plate assumptions has resulted in underestimation of loads on some anchor bolts.
Initial investigation indicated that nearly fifty percent of the base plates could not be assumed to behave as rigid plates.
ln addition, licensee inspection of anchor bolt installations at Shoreham has shown over fifty percent of the bolt installations to be deficiant.
Vendor Inspection Audits by NRC at Architect Engineering firms have shown a vide range of design practices and installation procedures which have been employed for the use of concrete expansion anchors. The current trends in the industry are toward more rigorous controls and verification of the instal-lation of the bolts.
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