MANUAL REACTOR SCRAM DUE TO REACTOR RECIRCULATION PUMPS DEGRADATION
"At 1215 [EDT] on 6/24/2016, James A. FitzPatrick (JAF) was
at 100% power when Breaker 710340 tripped and power was lost to L-gears
L13, L23, L33, and L43. These provide non-vital power to Reactor
Building Ventilation (RBV), portions of Reactor Building Closed Loop
Cooling (RBCLC), and 'A' Recirculation pump lube oil systems. Off-site
AC power remains available to vital systems and Emergency Diesel
Generators (EDG) are available.
"Due to the loss of RBV, Secondary Containment differential
pressure increased. At 1215 [EDT], Secondary Containment differential
pressure exceeded the Technical Specifications (TS) Surveillance
Requirement SR-3.6.4.1.1 of greater than or equal to 0.25 inches of
vacuum water gauge. The Standby Gas Treatment (SBGT) system was manually
initiated and Secondary Containment differential pressure was restored
by 1219 [EDT].
"The 'A' Recirculation pump tripped at 1215 [EDT] and
reactor power decreased to approximately 50%. 'B' Recirculation pump
temperature began to rise due to the degraded RBCLC system. At 1236
[EDT], a manual scram was initiated. Reactor Pressure Vessel (RPV) water
level shrink during the scram resulted in a successful Group 2
isolation. All control rods have been inserted. The RPV water level is
being maintained with the Feedwater System and pressure is being
maintained by main steam line bypass valves. A cooldown is in progress
and JAF will proceed to cold shutdown (Mode 4). Due to complete loss of
RBCLC system, the Spent Fuel Pool (SFP) cooling capability is degraded
but the Decay Heat Removal system remains available. SFP temperature is
slowly rising and it is being monitored. The time [duration] to 200
degrees is approximately 117 hours.
"The initiation of reactor protection systems (RPS) due to
the manual scram at critical power is reportable per 10 CFR
50.72(b)(2)(iv)(B) and 10 CFR 50.72(b)(3)(iv)(A). The general
containment Group 2 isolations are reportable per 10 CFR
50.72(b)(3)(iv)(A). In addition, the temporary differential pressure
change in Secondary Containment is reportable per 10 CFR
50.72(b)(3)(v)(C), as an event that could have prevented fulfillment of a
safety function."
The licensee notified the NRC Resident Inspector and the State of New York.
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