ML20059K975
| ML20059K975 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 06/29/1993 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| References | |
| PNO-I-93-033, PNO-I-93-33, NUDOCS 9311160258 | |
| Download: ML20059K975 (2) | |
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DCS No:' 50213930627 Date: June 29,1993 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE PN1-9333 This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest significance. The infonnation is as initially received without verification or evaluation, and is basically-all that is known by the Region I staff on this date.
Facility:
Licensee Emergency Classification:
Haddam Neck X
Notification of Unusual Event Connecticut Yankee Atomic Power Company Alen P. O. Box 270 Site Area Emergency Hanford, Connecticut 06141-0270 General Emergency Not Applicable Docket No.: 50-213 License No.: DPR-61 Event No.:
25682, 25701, 25706 Event Iecation Code: POW
Subject:
AUGMENTED INSPECTION TEAM DISPATCHED TO HADDAM NECK TO INVESTIGATE UNUSUAL EVENTS DURING ELECTRICAL TESTING On June 22,26 and 27,1993, the licensee declared Unusual Events (UEs) as a result of problems during electrical system testing. The facility is in cold shutdown on day 45 of its refueling outage.
The licensee classified each event appmpriately, in accordance with station procedures. However, during the last event, the licensee miscommunicated the event classification to the state, initially identifying it as an "Alen." The first event occurred when the site experienced a loss of all offsite power during testing of a "115 kV breaker failure protection" feature (non-safety related). The licensee determined the event was caused by a wiring error in the breaker failure protection circuit. A second loss of offsite power event occurred during the peiformance of technical specification "A" train partial loss of power surveillance testing. This event was caused by a blown fuse in the power supply for the undervoltage relay of the opposite non-safety 4.16 kV bus. The third event occurred when a safety related motor control center (MCC-5) failed to automatically shift to the alternate power supply during the "B" train partial loss of power surveillance test. The licensee is currently investigating this failure.
NRC management determined that the repetitive loss of offsite power, the apparent impact of non-safety related protective features on vital power supplies, concerns regarding a lack of redundancy with respect to safety-related loads powered by MCC-5, and the miscommunication of the event classification to the state, warranted review and evaluation by an Augmented Inspection Team (AIT). An AIT was dispatched on June 29,1993.
The State of Connecticut was notified of the AIT. The NRC plans to issue a press release upon completion of the AIT chaner.
This notification is current as of 2:00 p.m. on June 29,1993.
CONTACT:
Larry Doerflein Jim Trapp (215) 337-5378 (215) 337-5186 l
g-9311160258 930629 b
PDR I&E PNO-I-93-33 PDR g Sg T
' DCS No: 5021393 %
Date: June 29,1993 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE PN1-9333 DISTRIBUTION:
OWFN MNBB L-St.
NL Mail:
ADM:DMB Chairman Selin AEOD**
Comm. Rogers IRM Comm. Curtiss OIG**
NRC Ops Ctr**
Comm. Remick
, Comm. de Planque INPO**
OCAA NSAC**
OIP Phillips OCA-EDO ACRS**
OGC NMSS OPA NRR** (Phone Verif: A. Byrdsong 964-1168 or 964-1166)
OE OSP Regional Offices RI Resident Office EWW OIG Licensee:
(Reactor Licensees)
" General list for sending PN hy FAX Region I Form 83 (Rev. November 1992)