ML20236U533

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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

____. _ _ - _ _. _ _ _

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 during the shutdown. No emergency systems were required. The suppres-4 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

~

H. H. Brown, ISP T. J. McTiernan, AIA e'

D. F. Knuth, IE J. A. Harris, PA o f B. C. Rusche, NRR g

b o K. R. Chapman, NMSS H. K. Shapar, ELD b b H Sty _ @n ; MNBB 2.

Luge fn N

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Transmitted: P Bldg,1 0;

I PRELIMINARY NOTIFICATION - NOT FOR PUBLIC DISCLOSURE