2 septembre 2016
Le réacteur était à 100 % de sa puissance quand la fuite a été détectée à un niveau supérieur à 227 litres par heure. Selon les prescriptions réglementaires, ce niveau impose la mise à l’arrêt du réacteur. La fuite a atteint un niveau maximum de 308 l/h. Un réalignement des circuits a permis de réduire la fuite de moitié au bout de 39 h 33 minutes.
▸ Type : PWR - Puissance : 3 565 MWth - Première divergence : 05 / 1985 -
Available in english only
Event Number : 52218
Facility : WOLF CREEK - 4 State : KS
Unit : [1] - RX Type : [1] W-4-LP
Event Date : 09/02/2016 - Event Time : 08:08 [CDT]
Emergency Class : NON EMERGENCY 10 CFR Section : 50.72(b)(2)(i) - PLANT S/D REQD BY TS
Initial PWR : 100 % Current PWR : 0 %
Event Text
TECHNICAL SPECIFICATION REQUIRED SHUTDOWN
"While operating in MODE 1 at 100 percent rated thermal power and placing Excess Letdown in service for Reactor Coolant System (RCS) leak detection, RCS operational leakage exceeded 1 gpm [gallon per minute] unidentified leakage as identified by performing RCS Water Inventory Balance using the Nuclear Plant Information System Computer. This required the entry into Technical Specification (TS) Limiting Condition of Operation (LCO) 3.4.13 Condition B at 0808 [CDT] on 9/2/16. The associated action is to place the unit into Mode 3 in 6 hours. Trending of containment sump level indicates the leakage is inside containment with the exact location within containment unknown. Containment inspection is being performed to try and identify the source of Reactor Coolant System leakage. NRC Resident Inspector has been notified. Re-alignment of the Letdown System back to its normal arrangement has subsequently reduced RCS leak rate to 0.521 gpm at 0652 CDT on 9/2/16.
"Unusual or Not Understood - Leak Location is not known at this time."
Maximum leak rate recorded was 1.358 gpm. The leak was first discovered at 08/31/16 at 1519 CDT. Safety Related Equipment not operational - Reactor Vessel Level Indicating System (TS 3.3.3).
https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2016/20160906en.html