Monday, May 21, 2018

Troubled Columbia: Unstable SRV Design, Again

Update

Actually, there is little SRV LERs here. I find this suspicious. Why do we have tons of SRV LERs at plants I identified on my blog(Hatch, Pilgrim Hope...), while almost none at Columbia???

What is wrong with this picture? Columbia doesn't have a single SRV LER. Are they not reporting failures?

05000397

A transformer breakdown and a SRV problem is not a good thing at the same time? I haven't seen many LERs with SRV issues at Columbia?

Training troubles
On December 28, 2017, the licensee informed the inspector of the following operating test results:

• 5 of 6 crews passed the simulator portion of the operating test

• 50 of 57 licensed operators passed the simulator portion of the operating test

• 56 of 57 licensed operators passed the job performance measure portion of the operating test 
Actually, this plant is owned by the US government.
Power Reactor Event Number: 53410
Facility: COLUMBIA GENERATING STATION
Region: 4 State: WA
Unit: [2] [ ] [ ]
RX Type: [2] GE-5
NRC Notified By: SEAN KEEHN
HQ OPS Officer: STEVEN VITTO
Notification Date: 05/18/2018
Notification Time: 13:27 [ET]
Event Date: 05/18/2018
Event Time: 06:51 [PDT]
Last Update Date: 05/18/2018
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL
Person (Organization):
HEATHER GEPFORD (R4DO)
JEFFERY GRANT (IRD)
MICHAEL F. KING (NRR)

Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
2 A/R Y 100 Power Operation 0 Hot Shutdown

Event Text

AUTOMATIC REACTOR SCRAM CAUSED BY MAIN TRANSFORMER TRIP

"At 0651 [PDT] on May 18th, 2018, Columbia Generating station experienced a Main Transformer trip, that caused a Reactor Scram. Reactor Power, Pressure and Level were maintained as expected for this condition. MS-RV-1A (Safety Relief Valve) and MS-RV-1B (Safety Relief Valve) opened on reactor high pressure during the initial transient. MS-RV-1B appeared to remain open after pressure lowered below the reset point. The operating crew removed power supply fuses for MS-RV-1B and it currently indicates intermediate position. SRV (Safety Relief Valve) tail pipe temperatures indicate all valves are closed. Suppression pool level and temperature have remained steady within normal operating levels.

"All control rods inserted and reactor power is being maintained subcritical.

"RPV (Reactor Pressure Vessel) water level is being maintained with condensate and feed system with startup flow control valves in automatic. Reactor Pressure is being maintained with the Turbine Bypass valves controlling in automatic. The main condenser is the heat sink.

"No ECCS (Emergency Core Cooling Systems) systems actuated or injected; the EOC-RPT (End of Cycle-Recirculation Pump Trip) and RPS (Reactor Protection System) systems actuated causing a trip of the RRC pumps and a reactor scram.

"Core recirculation is being maintained with RRC-P-1A (Reactor Recirculation Pump) running.

"No release has occurred.

"At this time there will be no notifications to state, local or other public agencies.

"The NRC Senior Resident has been notified.

"The cause of the event is currently under investigation. Plant conditions are stable."

The plant is in its normal electrical alignment and offsite power is available to the site.

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