ML19323A597
| ML19323A597 | |
| Person / Time | |
|---|---|
| Site: | Zion File:ZionSolutions icon.png |
| Issue date: | 07/28/1977 |
| From: | Klinger G, Nolan F, Sniezek J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| References | |
| FOIA-79-149 PNO-III-77-131A, NUDOCS 8004210433 | |
| Download: ML19323A597 (1) | |
Text
_
IC b
July 28, 1977
/PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE--PNO 132A This preliminary notification censtitutes EARLY notice of an event of POSSIBLE saf z'.y or public interest sistnif ic ance. The inf ormation presented is as inirially received without verification or evaluation and is basically all that is kncvn by IE staff on this date.
Facility: ComcLonwealth Edison Company, Zion-Unit 2 C
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(DN 50-304), Zion, IL
Subject:
BY?ASSING OF SAFETY SIGNALS
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This supplenents PNO-77-131.
A meeting was held with Commonwealth Edison Corporate personnel on July 26, 1977, to discuss a July 12 incident in which some safety cystes circuits were temporarily disabled during routine testing while the plant was in a hot shutdown condition.
- te testing involved use of artificial signals in 31 safety circuits which sre intecdad to detect abnor=al conditions in part of the reactor With the safety sensors disabled for the test, the cooling system.
have automatically plants esergency core cooling system would not Other safety circuits respended to certain types of potential accidents.
vera unaffected and would have protected against potential accidents involving large pipe breaks.
During this coeting, the seriousness of this event and the associated draining of the 5,300 gallons of primary coolant from the reactor coolant cysten were discussed. If the draining of primary coolant had continued 5.r approx 1=ately 30 minutes longer, damage to the reactor coolant pu=p seals could have occurred. This could have resulted in a significant i
loss of primary coclant to the containment building.
The event appears to be a result of inadequate manage =ent attention and The licensee has instituted a program of corrective procedulal contro.'.s.
action to preclude repetition including revisions to procedures and administrative practice.
This PN is being issued because of high potential public interest expected upon an issuance of a planned press release by the NRC.
Contact:
GKlingler, XE x27451 GConstable, IE x27451 JSniezek I2 x27451 Distribution: Transmitted H St Cctruissionar Kennedy C. C. Kammerer, CA G. F. Murphy, JCAE Octruissioner Gilinsky S. J. Chilk, SECY H. H. 'w'hiteside, $CSE H. R. Myers, HCEE Transmitted: MNBB P Eldg SS Bldg L. V. Gossick, EDO E. G. Casa, NRR C. V. Snith, NMSS S. H. Hanauer, EDO J. A. Harris, PA J. G. Mcdonald, MIPC Luge (MAIL)
, E. Volgenau, IE R. G. Ryan, OSP T. J. mci 1ernan, OIA Legion
- 9. K. Shapir, ELD M1pmEEEmaEEBMW
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FRELIMINARY NOTIF~ CATION i
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