ML20085B513

Responds to 720519 Request for Insp of Reactor Vessel Head to Reassure Safety Significance.Rept Concludes Reactor Satisfactory for Unrestricted Operations.Ltr Rept Describing Spurious Actuation on 720517 Encl

ML20085B513
Person / Time
Site:	Palisades
Issue date:	06/01/1972
From:	Bacon J CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	Jensch S, Nyer W, Williams C AFFILIATION NOT ASSIGNED, Battelle Memorial Institute, PACIFIC NORTHWEST NATION, Atomic Safety and Licensing Board Panel
Shared Package
ML20085B488	List: ML20085B498 ML20085B513 ML20085B521 ML20085B527 ML20085B575 ML20085B598
References
NUDOCS 8307080168
Download: ML20085B513 (2)

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J. ...ai.h.. Company Geners! Attorner H r General Off.cas: 212 West Michigan Avenue. Jackson. Michigan 492O1. Area Code 517788 0500 C . E . Merritt O . M. Peterson Stuart H. Rednee w m.. a. wi.n., s June 1,.L972 Senoor Anarners Judd L. B. con Allen S. Wasa Charles D. Dawson R. , . Godbout o.... dye.H..."

Paula O. Hemisk AEC DOCKET NO. 50-255 - PALISADES PIANT Wayne A. Mirkby Albert D. McCallum W. R Mills John M. Restrick Dav6d R. Reed Joh. M. smith Mr. Samuel W. Jensch, Chainnan Dr. Clarke Williams A . r, ud'r*

1. "'"'" Atomic Safety and Licensing Board Brookhaven National Laboratory U. S. Atomic Energy Commission Upton, L.I., New York 11973 Washington, D. C. 20545 Mr. Warren E. Nyer Idaho Nuclear Corporation P.O. Box 1845 Idaho Falls, Idaho 83401 Gentlemen:

By letter,of May 19, 1972, AEC-DL requested the Applicant to remove the Palisades reactor vessel head and inspect the upper guide structure and, if necessary, other components to "obtain greater assurance" that the shoulder bolt failure reported in our communi-cations of May 15 and 16 was not "sy.nptomatic of some problem, not presently recognized, that might have greater safety significance than the cause of the failure" postulated by the Applicant. The Applicant was advised that the results of the inspection should be reported to the Directorate of Operations, together with an analysis of the suitability of the reactor for future operation.

O The requested inspection was made, and a copy of the 'IWX re-

/JL port to the Directorate of Operations, dated May 26, 1972, is enclosed.

g' The inspection confirmed that the portion of the shoulder bolt recovered d; frcan the No. 2 steam generator on May 7 had come from the No.1 locating bolt position on the UGS ring shim. The 5/8" shoulder bolt at the No. 7 position on the ring shim was also found to have been severed, and the loose portion was removed. Both bolt failures are believed to have resulted from impact forces occurring in the May 1969 shipping accident, together with normal loads to which the bolts have been subjected. Lock bars have been installed at the other ring shim bolt locations to prevent the other bolts from escaping. Even if 8307080160 720712 + gh I PDR ADOCK 05000255 j s

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o Atomic Cafety and Licensing Board o 2 June 1, 1972 all the remaining bolts failed, reactor operation would not be affected. The report concludes that the reactor is satisfactory for unrestricted operation at licensed power levels. The Plant is presently being returned to power operation.

Also enclosed is a May 26, 1972, letter report from Ralph B. Sewell to E. J. Bloch describing the spurious actuation of a differential relay on the 2400-volt startup transformer during a test conducted on May 17 while the Plant was in a hot standby con-dition, and the failure of a level switch on a diesel generator fuel reservoir on May 18 under hot standby conditions. Both problems have been corrected. The safety injection system test mentioned in the sixth paragraph on page 2 of the letter has been performed, and the results were entirely satisfactory.

Yours very truly,

/s/ Judd L. Bacon JLB/bbm Judd L. Bacon CC: Eric V. Brown, Sr., Esq.

Myron M. Cherry, Esq. ,

Lewis D. Drain, Esq.

Marvin F. Metge, Esq.

Joseph F. Scinto, Esq.

George F. Trowbridge, Esq.

Mr. Stanley T. Robinson, Jr.

Algie A. Wells, Esq.

Nathaniel H. Goodrich, Esq.

Curtis G. Beck, Esq.

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