Event Notification Report for May 03, 2015
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
05/02/2015 - 05/03/2015
EVENT NUMBERS
51036
Power Reactor
Event Number: 51036
Facility: WOLF CREEK
Region: 4 State: KS
Unit: [1] [] []
RX Type: [1] W-4-LP
NRC Notified By: LARRY HAUTH
HQ OPS Officer: DANIEL MILLS
Region: 4 State: KS
Unit: [1] [] []
RX Type: [1] W-4-LP
NRC Notified By: LARRY HAUTH
HQ OPS Officer: DANIEL MILLS
Notification Date: 05/03/2015
Notification Time: 12:56 [ET]
Event Date: 05/03/2015
Event Time: 10:22 [CDT]
Last Update Date: 05/03/2015
Notification Time: 12:56 [ET]
Event Date: 05/03/2015
Event Time: 10:22 [CDT]
Last Update Date: 05/03/2015
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
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Person (Organization):
GEOFFREY MILLER (R4DO)
GEOFFREY MILLER (R4DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | M/R | Y | 22 | Power Operation | 0 | Hot Standby |
FEEDWATER ISOLATION, TURBINE TRIP AND MANUAL REACTOR TRIP DURING POWER ASCENSION
"On 5/3/2015 during power ascension following Refueling Outage 20, Steam Generator 'C' water level increased rapidly, causing a Feedwater isolation on high Steam Generator water level and an associated Turbine trip. The reactor was subsequently manually tripped.
"At the start of the event, reactor power was approximately 22%. Plant staff was in the process of transferring from Main Feedwater Bypass Feed Regulating Valve control, used for low power control, to Main Feedwater Regulating Valve control as part of power ascension. When the Main Feedwater Regulating Valve for 'C' Steam Generator (AEFCV-530) was opened, it went to about 80% open, causing an overfeed of the 'C' Steam Generator. High Steam Generator water level in 'C' Steam Generator initiated an automatic Feedwater Isolation Signal, automatic Turbine Trip and automatic trip of the operating main feed pump. The operating crew initiated a manual reactor trip.
"The Auxiliary Feedwater System automatically initiated as part of the plant response to the feedwater system transient.
"The plant is presently stable in Mode 3. All equipment functioned normally, except the 'C' Main Feedwater Regulating Valve (AEFCV0530) which did not function to properly control Steam Generator level. This valve did function as designed to close on the Feedwater Isolation Signal.
"NRC Resident Inspector has been contacted."
"On 5/3/2015 during power ascension following Refueling Outage 20, Steam Generator 'C' water level increased rapidly, causing a Feedwater isolation on high Steam Generator water level and an associated Turbine trip. The reactor was subsequently manually tripped.
"At the start of the event, reactor power was approximately 22%. Plant staff was in the process of transferring from Main Feedwater Bypass Feed Regulating Valve control, used for low power control, to Main Feedwater Regulating Valve control as part of power ascension. When the Main Feedwater Regulating Valve for 'C' Steam Generator (AEFCV-530) was opened, it went to about 80% open, causing an overfeed of the 'C' Steam Generator. High Steam Generator water level in 'C' Steam Generator initiated an automatic Feedwater Isolation Signal, automatic Turbine Trip and automatic trip of the operating main feed pump. The operating crew initiated a manual reactor trip.
"The Auxiliary Feedwater System automatically initiated as part of the plant response to the feedwater system transient.
"The plant is presently stable in Mode 3. All equipment functioned normally, except the 'C' Main Feedwater Regulating Valve (AEFCV0530) which did not function to properly control Steam Generator level. This valve did function as designed to close on the Feedwater Isolation Signal.
"NRC Resident Inspector has been contacted."