ML20086H068

Telecopy AO 75-70:on 751024,drywell Purge Supply Isolation Valve AO-3520 Operated W/O Manual Initiation.Caused by Incorrect Implementation of Mod.Valve Failed Closed & Will Be Repaired

ML20086H068
Person / Time
Site:	Peach Bottom
Issue date:	10/24/1975
From:	Ullrich W PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20086H066	List: ML20086H062 ML20086H068
References
AO-75-70, NUDOCS 8401130384
Download: ML20086H068 (1)

Text

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O - ~ Il i _- ~ PHILADELPiiIA ELECTRIO COMPANY. -- ' 1 _ panch onetem ten-4n unear n+netnA - --- -~~" - Delta,' Pennsylvania  ; 314 October 24, 1975 I i Mr. James P. O'Reilly, Director Office of Inspection and Enforcement g_

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United States Nuclear Regulatory Commission

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h*?f z ?_hmM{m ,J, 1 631 Park Avenue. s King of Prussia, Pennsylvania 19406 {.

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Subject:

Abnormal Occurrence 24-Hour Notification a Confirming R. S. Fleischmann's phone conversation with Mr. Walt Baunack, ]1 Region 1. United States Nuclear Regulatory Commission on October 24, 1975

Reference:

License Number DPR-56 <

                                                                                                                                              ,1 Technical Specification 

Reference:

3.7.D.1

 -                     Report No.:

d l Report Date: 50-279-75-{)70 October 2 , 1975 x Cecurrence Date: October 24, 1975 i' Facility: Peach Bottom Atomic Power Station 2] j R.D. 1. Delta, Pennsylvania 17314 i i Identification of Occurrence: 3 Drywell Purge Supply Isolation Valve (AO-3520) opening. E Conditions Prior to Occurrence: $ Reactor power 57%. i w i Description of Occurrence: I \ Valve AO-3520 apparently operated without manual initiation. I Designation of Apparent Cause of Occurrence: I 4 It appears that an air piping modification made-to similar valves to , correct a similar problem in early 1974 was implemented incorrectly on this valve. '

    '                 Analysis' of Occurrence:                           .

1 The other isolation valve in series with this valve would have isolated if necessary. Therefore, there is minimal safety significance. Corrective Action: The valve was, failed closed and will be repaired. All other valves of similar air piping arrangement will be inspected. i Failure Data:

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1 Abnormal Occurrence Report 50-278-74-15 Very truly yours,

                                                                                                                                            )

W. T. Ullrich, Superintendent

       ;              Peach Bottom Atomic Power Station i

l i . 8401130384 751103 _. _..m. A' __ P,DRADOCK05000g8 . j

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