9 janvier 2016
C’est un orage qui est à l’origine du problème. Même présenté de façon sibylline, suite à l’arrêt du circuit de vapeur, ce sont les soupapes qui ont permis de refroidir le réacteur selon la NRC. Toujours selon cette autorité, le circuit d’injection d’eau de sécurité a été enclenché. Selon les données standards de la NRC, sur ce type de problème, il est fort probable que de la radioactivité ait été dispersée dans l’environnement...
Type : BWR Mark3 - Puissance : 3 091 MWth - Première divergence : 10/1985
Available in english only.
Event Number : 51644
Facility : RIVER BEND
State : LA - Unit : [1]
RX Type : [1] GE-6 - Event Date : 01/09/2016 - Event Time : 02:37
Last Update Date : 01/09/2016 Emergency Class : NON EMERGENCY 10 CFR Section : 50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Initial PWR : 100 %
Current PWR : 0 %
Event Text
AUTOMATIC REACTOR SCRAM ON MAIN STEAM ISOLATION DUE TO ELECTRICAL FAULT
"On 1/9/16 at 0237 [CST], River Bend Station sustained a reactor scram during a lightning storm. An electrical transient occurred resulting in a full main steam isolation [MSIV] (Group 6) and a Division II Balance of Plant isolation signal. During the scram, level 8 occurred immediately which tripped the feed pumps. A level 3 signal occurred also during the scram. Subsequent level 3 was received three times due to isolated vessel level control. The plant was stabilized and all spurious isolation signals reset, then the MSIVs were restored. The plant is now stable in Mode 3 and plant walkdowns are occurring to assess the transient."
During the scram, all rods inserted into the core. The plant was initially cooled down using safety relief valves. Offsite power is available and the plant is in its normal shutdown electrical lineup.
The licensee has notified the NRC Resident Inspector.
https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2016/20160111en.html#en51644