ML20236V043
| ML20236V043 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 09/15/1975 |
| From: | Jennifer Davis, Dreher F, Thornburg H NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | |
| References | |
| PN-75-091, PN-75-91, NUDOCS 9807310258 | |
| Download: ML20236V043 (1) | |
Text
W[]ft.
WWAn(L
&J l&
& fddWLgv PmTmMARY NOTIFICATION - NOT FOR PUBLIC DISCLOSURE September 15, 1975 w
PRELIM'. NARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE
--PN-75-91 p,
.2I This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest significance.
The information presented is as initially received without verification or evaluation j
and is basically all that is known by OIE staff as of 9:30 a.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) SUBSEQUENTLY WILL BE ISSUED IF WARRANTED.
Facility: Pilgrim 1
. Boston Edison Company
+ =a Subj ect:
POWER LOSS AND SUBSEQUENT BLOW DOWN During a shut down at 1331 hours0.0154 days <br />0.37 hours <br />0.0022 weeks <br />5.064455e-4 months <br /> on September 13, 1975, to perform maintenance on a valve packing leak, and while switching the turbine generator off line, two switchyard breakers malfunctioned resulting in a loss of power to the emergency busses.
A reactor scran occurred and the emergency diesels started and restored power. Two relief valves operated, one manually and one automatically
- to control reactor pressure.
sq The HPCI initiated automatically a's designed, however, was switched off
(
when reactor level returned to normal. The "B" Target Rock relief valve failed to close and pressure was reduced to 275 psig at which time the valve reseated.
ECCS systems performed as designed to provide make up water to the reactor.
The licensee is investigating the cause of the breakers and Target Rock relief valve failures.
There were no activity releases resulting from the incident. The licensee
/c is initiating a two week preplanned maintenance outage to perform condenser
/
repairs.
Media interest is expected'because of prior local interest. The State of A
F Massachusetts has been and is being kept informed. A press release is not k
planned.
4
~
OIE received notification of this occurrence by telephone from Station SuperifiTendent at 5f00 p.m., 9/13/75.
n
Contact:
FAD.eher, IE x7261 HDThornburg, IE x7353 JGDavis, IE x7541 ts to Distribution:
$Wy Chairman Anders Commissioner Mason S. J. Chilk, SECY Ogo Commissioner Gilinsky Commissioner Rowden G. F. Murphy, JCAE dm n Commissioner Kennedy C. C. Kammerer, CA N [
L. V. Gossick, EDO vidb l
f s.
Q D. F. Knuth, IE J. A. Harris, PA B. C. Rusche, NRR H. H. Brown, ISP T. J. McTiernan, AIA K. R. Chapman, NMSS H. K. Shapar, ELD Transmitted: P Bldg fern. ; E S t do ;,,-; MNBB.Actr+;
Lugeeui[
l