Just saying, a well maintained plant scram should go like this, a component fails, then the scram should occur without any other component failures or observed component degradation and the operator should be error free. Multiple equipment failures showing up in one scram is very serious...
6/02 Event Report: The transient began with a trip of Reactor Feed Pump 'A', followed by a Reactor Scram and a trip of Reactor Feed Pump 'C'.It is startling after all this NRC attention and all the recent problem in River Bend: it initiated from a feed water trips, then another feed water trip and then issues with the Reactor Feedwater Master Level Controller problems.
Actually is sounds like a out of control Reactor Feedwater Master Level Controller set this whole thing off.
NRC to me: Jan 21, 2015 No: IV-15-003 "during which you expressed concern related to equipment issues leading to scrams and operator performance following scram."The Pilgrim special inspection turned into being a train wreck, we recently got a special inspection on Indian Point, along with the two special inspection at River Bend. That is four inspection ongoing at Entergy Plants...at least 38% of their sites under special inspection. The double hitter River Bend special Inspection should be released within days.
Imagine that, another set of feed pump trips, pathetic!!!
Unprecedented NRC attention at River Bend with feed pump trips, out of control reactor water lever control and scrams...now we got another one.
The symptoms of a totally impotent NRC...
The next Pilgrim scram or down power is right around the corner?
| Power Reactor | Event Number: 51112 |
| Facility: RIVER BEND Region: 4 State: LA Unit: [1] [ ] [ ] RX Type: [1] GE-6 NRC Notified By: JACK MCCOY HQ OPS Officer: DANIEL MILLS | Notification Date: 06/02/2015 Notification Time: 02:00 [ET] Event Date: 06/01/2015 Event Time: 21:11 [CDT] Last Update Date: 06/02/2015 |
| 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 | Person (Organization): JACK WHITTEN (R4DO) |
| Unit | SCRAM Code | RX CRIT | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
| 1 | A/R | Y | 90 | Power Operation | 0 | Hot Shutdown |
| REACTOR SCRAM DUE TO LOW REACTOR WATER LEVEL "At 2111 [CDT] River Bend Nuclear Station sustained an Automatic Reactor Scram due to low Reactor Water Level (Level 3). The plant is currently stable, with level being maintained in a normal band of 10 - 51 inches with Condensate and Feedwater. Reactor Pressure is in the prescribed band of 500-1090 psig. The plant is in Mode 3, Hot Shutdown, and will remain in Mode 3 until investigation of the scram is complete. The transient began with a trip of Reactor Feed Pump 'A', followed by a Reactor Scram and a trip of Reactor Feed Pump 'C'. Reactor water level was recovered with Reactor Feed Pump 'B' to a normal post scram level band. There was a problem noted with the Reactor Feedwater Master Level Controller; this was mitigated by the Operator placing the controller to manual. There was no subsequent Level transient. Reactor Pressure was stabilized in normal pressure band with Turbine bypass valves. During the transient, a Reactor Recirculating Flow Control Valve Runback was not received as expected. Reactor Recirculating Pump 'A' responded as expected to transient [switching to low pump speed], Reactor Recirculating Pump 'B' tripped during transient. A Level 3 isolation signal was received, all expected isolations occurred. "The cause of the transient is currently under investigation." The reactor is stable in Mode 3 with decay heat being removed via turbine bypass valves, and a normal electrical line up. The NRC Resident Inspector has been notified. * * * UPDATE FROM JACK MCCOY TO HOWIE CROUCH AT 0712 EDT ON 6/2/15 * * * "At 2231 on 6/1/15, Reactor Water Cleanup System isolated on High Reactor Water Cleanup System Heat Exchanger room temperature due to loss of Turbine Building chill water during the initial transient. All Reactor Water Cleanup System Valves isolated as expected. Reactor Water Cleanup was the only system affected by this isolation signal." The licensee has notified the NRC Resident Inspector |
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