ML19224D472
| ML19224D472 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 06/21/1979 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Jeffery Grant TOLEDO EDISON CO. |
| References | |
| NUDOCS 7907120257 | |
| Download: ML19224D472 (1) | |
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Jtill 211979 Docket No. 50-346 Toledo Edison Company ATTN:
Mr. James S. Grant Vice President - Energy Supply Edison Plaza 300 Madison Avenue Toledo, OH 43652 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 regarding this Bulletin or the actions required by you, please contact this office.
Sincerely, M
> James G. Keppler Director
Enclosure:
IE Bulletin No. 79-02 Revision No. -
cc w/ encl:
Mr. T. Murray, Station Superintendent Central Files Director, NRR/DPM Director, NRR/ DOR PDR mocal PDR NSIC TIC Harold W. Kohn, Power Siting Commission Helen W. Evans, State of
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U.S. NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT REGION 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 or. March 8,1979, IE inspection g
experience and many inquiries from licensees indicate that additional informa-tion and clarification 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 supersedes 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 cf satisfying the Bulletin requitcments.
While performing inservice inspections during a Sfarch-April 1978 refueling outage at Millstone Unit 1, structural failures 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 prcperly.
Deficiency reports, in accordance with 10 CFR 50.55(e), filed by Iong Island Lighting Company on Shoreham Unit 1, indicate that design of basa plates using rigid plate assumptions has resulted in underestimation of loads on some anchor bolts.
Initial investigation indicated tnat nearly fifty percent of the base plates could not be assumed to behave as rigid plates.
In addition, licensee inspection of anchor bolt installations at Shoreham has shown over fifty percent of the bolt installations to be deficient.
Vendor Inspection Audits by NRC at Architect Engineering firms have shown a wide 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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