ML20236V276
| ML20236V276 | |
| Person / Time | |
|---|---|
| Site: | Quad Cities  |
| Issue date: | 09/02/1975 |
| From: | Jennifer Davis, Thornburg H, Warnick R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | |
| References | |
| PN-75-081, PN-75-81, NUDOCS 9808030052 | |
| Download: ML20236V276 (1) | |
Text
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hs 3 &lk PRELIMINARY NOTIFICATION - NOT FOR PUBLIC DISCLOSURE l
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September 2, 1975 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE
--PN-75-81 gf, This preliminary notification constitutes EARLY notice of events of pe POSSIBLE safety or public interest significance. The information b
presented is as initially received without verification or evaluation and is basically all that is known by 01E staff as of 9:00 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:
Commonwealth Edison Company (Quad-Cities Unit 2)
Subject:
UNIT SHUTDOWN REQUIRED BY FAILURE OF BACKUP SAFETY COMPCNENTS The licensee reported that during a. surveillance test, the HPCI turbine could not be brought up to required speed. During subsequent testing of other ECCS equipment it was determined that the RCIC turbine could not be brought up to full speed due to an overspeed trip problem.
The licensee began a controlled shutdown from 540 MWe as required by Technical Specifications. When the unit was at 408 MWe the feedwater system developed a transient accompanied by unusual vibration, causing a reactor scram on high water level.
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Two 3/4-inch feedwater drain lines broke during the transient.
The feedwater system was isolated to prevent further damage.
E The feedwater pumps were required'to be restarted one more time to
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maintain water level in the reactor subsequent to the transient.
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The reactor pressure was reduced by opening the bypass valves to the condenser to the point (approximately 550 psig) where the RCIC turbine was effective in maintaining level in the reactor vessel at the reduced speed.
The reactor core was covered at all times and reactor water level was always under control.
Core spray and the RHR systems were available if required. The licensee expects the plant to be down several days for evaluation and correction of problems.
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The licensee issued a press release. The states of Iowa and Illinois were notified. A reactor inspector was dispatched to the site on August 31, 1975.
Region III is preparing a press release.
RegionIIIreceivednotificationoft$1soccurrencebytelephone No n.
from QW:monwealth Edison Company at 0630, on August 31, 1975.
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Contact:
RFWarnick, IE x7261 HDThornburg, IE x7353 JGDavis, IE x7541 l
Distribution:
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j in w Chairman Anders Commissioner Mason S. J. Chilk, SECY Com=issioner Gilinsky Commissioner Rowden G. F. Murphy, JCAE
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Commissioner Kennedy C. C. Kammerer, CA to N (i@$$
L. V. Gossick, EDO D. F. Knuth, IE J. A. Harris, PA l
' & Q 0-B. C. Rusche, NRR H. H. Brown, ISP T. J. McTiernan, AIA l
a K. R. Chapman, NMSS H. K. Shapar, ELD
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Transmitted: P Bldg n t N ; H St f. M p; MNBB A.7 J /' ; Luge.
PRELIMINARY NOTIFICATION - NOT FOR PURT.TC DTSCT.0SURT i