ML19276H478
| ML19276H478 | |
| Person / Time | |
|---|---|
| Site: | Dresden, Byron, Braidwood, Quad Cities, Zion, LaSalle  |
| Issue date: | 11/08/1979 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Reed C COMMONWEALTH EDISON CO. |
| References | |
| NUDOCS 7911290004 | |
| Download: ML19276H478 (1) | |
Text
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El Tc=as Docket Nos. 50-10, 50-237, 50-249, 50-254, 50-265, 50-295, 50-304, 50-373, 50-374, 50-454, 50-455, 50-456 and 50-457 Commonwealth Edison Company ATTN:
Mr. Cordell Reed Manager of Nuclear Operations Post Office Box 767 Chicago, IL 60690 Gentlemen:
Enclosed is IE Bulletis No. 79-02, Revision No. 2 which requires action by you with regard to your power reactor facilities with an operating license or a construction parmit.
Should you have any questions regarding this Bulletin Revision or the actions required by you, please contact this office.
Sincerely, James G. Keppler Director
Enclosure:
IE Bulletin No. 79-02, Revision No. 2 cc w/ encl:
Mr. D. L. Peoples, Director Mr. Gunner Sorensen, Site of Nuclear Licensing Project Superintendent Mr. B. B. Stephenson, Mr. R. Cosaro, Project Station Superintendent Superintendent Mr. N. Kalivianakis, Central Files Station Superintendent Director, NRR/DPM Mr. N. Wandke, Station Director, NRR/ DOR Superintendent PDR Mr. L. J. Burke, Site Local PDR Project Superintendent NSIC Mr. T. E. Quaka, Quality TIC Assurance Supervisor Anthony Roisman, Esq., Attorney Mr. R. H. Holyoak Mr. Dean Hansell, Office Station Superintendent of Assistant Attorney General
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UNITED STATES SSINS No.:
6E;0 NUCLEAR REGULATORY COMMISSION Accession No.:
OFFICE OF INSPECTION AND ENFORCEMCd 7908220136 WASHINGTON, D.C.
20555 November 8, 1979 IE Bulletin No. 79-02 (Revision 2)
PIPE SUPPORT BASE P!. ATE DESIGNS USING CONCRETE EXPANSION ANCHOR BOLTS Description of Circumstances:
Inspection experiences and the review of licensee response have identified several R2 areas where the Bulletin intent has not been adequately addressed by licensees.
R2 Revision No. 2 of the Bulletin is intended to clarif, the intent of the Bulletin R2 and establish the NRC positions on minimum factors of s,fety, anchor bolt preload, R2 and the expected date of completion for certain Bulletin actions.
R2 Since the issuance of IE Bulletin No. 79-Oc on March 8, 1979, IE inspection R1 experience and many inquiries from l uensees indicate that additional informa-R1 tion and clarification is needed.
This revision is intended to serve that R1 purpose.
None of the requirements of tF: oriM aal Bulletin have been deleted, R1 and the due date for completion of the requested actions (July 6, 1979) has R1 not been changed.
The following text supersedes the text of Bulletin No. 79-02.
R1 Changes from the original text are identified by R1, R2 in the margin. The purpose R1 of this revision is to identify acceptable ways of satisfying the Bulletin R1 requirements.
R1 While performing inservice inspections during a March-April 1978 refueling outage at Millstone Unit 1, structural failures of piping supports for safety equipment were observed by t.he licensee.
Subsequent licensee inspections of undamaged supports showed is large percentage of the concrete anchor bolts were not tightened properly.
Deficiency reports, in accordance with 10 CFR 50.55(e), filed by Long Island Lighting Company on Shoreham Unit 1, indicate that 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.
In addition, licensee inspection of anchor bolt installations at Shoreham has shown over fif ty 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 installation of the belts.
The data available on dynamic testing fatigue failures can occur at loads s R1 and R2 - Identifies those additions Entire document previously entered into system under:
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