ML20236U533

PNS-75-053:on 750720,licensee Reported That During Attempt to Reseat D Rv Which Was Observed to Be Leaking,Valve Was Manually Actuated.Valve Did Not Reseat.Reactor Was Manually Scrammed.Licensee Investigating Cause of Rv Failure

ML20236U533
Person / Time
Site:	Pilgrim
Issue date:	07/21/1975
From:	Jennifer Davis, Dreher F, Thornburg H NRC OFFICE OF INSPECTION & ENFORCEMENT (IE)
To:
References
PN-75-053, PN-75-53, NUDOCS 9807300250
Download: ML20236U533 (1)

Text

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I PRELIMINARY NOTIFICATION - NOT FOR PUBLIC DISCLOSURE July 21, 1975 l 1

I PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE --PN-75-53 l l

This preliminary notification constitutes EARLY notice of events of i

> POSSIBLE safety or public interest significance. The information presented is as initially received without verification or evaluation l

and is basically all that is known by OIE staff as of 1:30 p.m. on the date of this notification. IT SHOULD BE SPECIFICALLY NOTED THAT THIS  ;

NOTIFICATION MAY CONTAIN INFORMATION THAT LATER MAY BE DETERMINED TO BE INACCURATE OR INCONSISTENT. AN OFFICE OF INSPECTION AND ENFORCEMENT NOTIFICATION OF AN INCIDENT OR OCCURRENCE (BLUE SHEET) SUBSEQUEITILY I

• WILL BE ISSUED IF WARRANTED.

' Facility: ' Pilgrim 1 Boston Edison Company

Subject:

BLOWDOWN DUE TO FAILURE OF A SAFETY / RELIEF VALVE TO RESEAT FOLLOWING MANUAL ACTUATION The licensee reported that at 12:55 p.m. on July 20, 1975, during an i attempt to reseat the D relief valve which was observed to be leaking, i the valve was manually actuated; however, it did not reseat. The reac-tor was manually scrammed. The attempt to properly reseat the relief valve was conducted at operating temperature and pressure and a reactor er

~

power level of~54%. The reactor pressure was reduced from 980 psig to )

200 psig at which time the valve closed. All systems oper'ated normally '

4 during the shutdown. No emergency systems were required. The suppres-sion pool temperature reached a temperature of 112 degrees F during the blowdown. The licensee is investigating the cause of the valve failure and the effects of the blowdown. Region I expects the plant to be shutdown for 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.

Media interest is expected because of news attention being given to Pilgrim 1. $

/l The State of Massachusetts is being kept informed. A press release is not planned. dI h!

OIE received notification of this occurrence by telephone from the gl

<, licensee at 11:50 a.m. on July 21, 1975. i

Contact:

FAdreher, IE x7261 HDThornburg, IE x7353 JGDavis, IE x7541' l gfD_istributfon: ..

l 8 Chairman Anders Commissioner Mason S. J. Chilk, SECY l @ Commissioner Gilinsky Commissioner Rowden G. F. Murphy, JCAE l 5 Commissioner Kennedy C. C. Kammerer, CA o O M L. V. Gossick, EDO ~

e' D. F. Knuth, IE J. A. Harris, PA o f B. C. Rusche, NRR g H. H. Brown, ISP T. J. McTiernan, AIA b o K. R. Chapman, NMSS H. K. Shapar, ELD b b

\ c: Transmitted: P Bldg,1 0; H Sty _ @n ; MNBB 2.  ; Luge fn N

! I PRELIMINARY NOTIFICATION - NOT FOR PUBLIC DISCLOSURE