ML071990428
| ML071990428 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 07/17/2007 |
| From: | Barber G S Division Reactor Projects I |
| To: | |
| Barber G S, RGN-I/DRP/610-337-5232 | |
| References | |
| 05000219071707 PNO-I-07-006 | |
| Download: ML071990428 (3) | |
Text
DCS No.: 05000219071707Date: July 17, 2007PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE -- PNO-I-07-006This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or publicinterest significance. The information is as initially received without verification or evaluation, andis basically all that is known by the Region I staff on this date.FacilityAmergen Energy Company, LLCOyster CreekForked River, NJDocket: 50-219Licensee Emergency Classification Notification of Unusual Event Alert Site Area Emergency General Emergency X Not Applicable
SUBJECT:
REACTOR SCRAM ON LOW REACTOR VESSEL WATER LEVEL DUE TO ATRIP OF THE 'C' REACTOR FEED PUMP On July 17, 2007, at 5:22 a.m., the Oyster Creek reactor scrammed due to a low reactor waterlevel following a trip of the 'C' Reactor Feed Pump (RFP). Reactor water level reached the low-low level setpoint which, among other actions, automatically isolated the main steam isolationvalves and initiated the isolation condensers. The isolation condensers steam off plantcondensate to remove decay heat. Although there was no abnormal amount of radioactivityreleased during the event, a small amount of activity was released by steaming off condensatethat contained trace amounts of radioactive tritium. The preliminary estimates of the activityreleased was about 1.05 curies which resulted in a worst case offsite dose of about 0.005 millirem which is about 3000 times less than the annual organ limit of 15 millirem and 25millirem total body. Immediately prior the scram, reactor water level had decreased due to a steam flow/feed flowmismatch. After the scram, water level increased due to excessive feeding causing a highreactor water level which necessitated cycling two Electromagnetic Relief Valves (EMRVs). The steam relief from the EMRVs caused an increase in the torus temperature that wascontrolled by using the Containment Spray System in torus cooling mode. No emergencyaction level was declared as a result of this event. The reactor was placed in a cold shutdowncondition at 2:00 p.m., July 17, 2007. Preliminary information indicates that the 'C' RFP tripped due to an electrical fault. Plannedlicensee actions include a review to determine the cause of the 'C' RFP trip, repairs to the 'C'RFP, and a review of plant and operator response during the event. The NRC resident inspector responded to the site and has been supported by regionalinspectors during the NRC's initial assessment of this event. The NRC is continuing to assessthe licensee's response to this event. The facts of this Preliminary Notification were verifiedwith the Oyster Creek Plant Manager and were current as of 4:00 p.m., July 17, 2007.
2AmerGen has issued an event notification (EN #43495) in accordance to 10 CFR 50.72 andhas issued press releases. The state of New Jersey has been notified. This PN will be updated as close to plant restart as possible.ADAMS Accession Number: ML071990428 CONTACT:G. Scott Barber(610) 337-5232 3DISTRIBUTIONS
- BY E-MAIL:OWFN TWFNChairman Klein Comm. McGaffigan Jr.NMSSComm. JaczkoOIGComm. LyonsRES OIPOCA OGC EDO OE NRR SECYRegional OfficesBY FAX: DOT:TransINPO NSACRI Resident OfficeLicensee:AmerGen Energy Company, LLC Oyster Creek Nuclear Generating StationADAMS ML071990428 SUNSI Review Complete: GSB (Reviewer's Initials)DOCUMENT NAME: T:\DRP\PNs\PNO-I-07-006 Oyster Creek scram due to a loss of C RFPRev 2.wpdAfter declaring this document "An Official Agency Record" it will be released to the Public.To receive a copy of this document, indicate in the box:
" C" = Copy without attachment/enclosure
" E" = Copy with attachment/enclosure " N" = No copyOFFICERI/DRP RI/ORARI/ORARI/DRPNAMESBarber/GSBDScrenci/DPS MMcLaughlin/MMDLew/DCLDATE07/17/0707/17 /0707/17/0707/18 /07OFFICIAL RECORD COPYRegion I Form 83 (Rev. July 2, 2003)