27 mars 2017
Lors opérateurs effectuaient des tests sur des commutateurs de température pour le circuit d’isolement du liquide de refroidissement du cœur du réacteur. Ils ont isolé par inadvertance le circuit d’injection (HPCI) le rendant, de fait, inutilisable. La déclaration a été faite suite à la perte, durant 40 mn, d’une fonction de sécurité nécessaire à atténuer les conséquences d’un accident.
Type : Fukushima 1 (BWR Mark 1) - Puissance : 2 028 MWth - Première divergence : 1 / 06 / 1972 -
Available in english only
Event Number : 52643
Facility : PILGRIM
State : MA
Unit : [1] [- RX Type : [1] GE-3
Event Date : 03/27/2017 - Event Time : 18:25 [EDT]
Emergency Class : NON EMERGENCY 10 CFR Section : 50.72(b)(3)(v)(D) - ACCIDENT MITIGATION
Initial PWR : 100 % - Current PWR : 100 %
Event Text
HPCI DECLARED INOPERABLE DUE TO INADVERTENT ISOLATION
"On March 27, 2017, at 1825 hours EDT, with the reactor at 100 percent core thermal power and steady state conditions, technicians inadvertently caused a High Pressure Coolant Injection (HPCI) System isolation, by testing the incorrect temperature switches in the TIP [Traversing In-core Probe] room. Pilgrim Nuclear Power Station (PNPS) was performing testing on the temperature switches for Reactor Core Isolation Cooling (RCIC), but the HPCI temperature switches were inadvertently actuated causing HPCI to isolate.
"The Limiting Condition for Operation (LCO) Action Statement 3.5.c.2 has been entered and the planned testing has been secured pending further investigation. PNPS is providing an 8-hour non-emergency notification that the HPCI System was declared inoperable in accordance with 10 CFR 50.72(b)(3)(v)(D), an event or condition that could have prevented fulfillment of a safety function needed to mitigate the consequences of an accident. HPCI was returned to Operable within 40 minutes."
The licensee notified the NRC Resident Inspector and the Commonwealth of Massachusetts.
https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2017/20170328en.html