Event Notification Report for December 11, 2017
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
12/10/2017 - 12/11/2017
EVENT NUMBERS
53112
Power Reactor
Event Number: 53112
Facility: WATTS BAR
Region: 2 State: TN
Unit: [] [2] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: BRIAN McILNAY
HQ OPS Officer: MARK ABRAMOVITZ
Region: 2 State: TN
Unit: [] [2] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: BRIAN McILNAY
HQ OPS Officer: MARK ABRAMOVITZ
Notification Date: 12/11/2017
Notification Time: 11:06 [ET]
Event Date: 12/11/2017
Event Time: 08:57 [EST]
Last Update Date: 12/11/2017
Notification Time: 11:06 [ET]
Event Date: 12/11/2017
Event Time: 08:57 [EST]
Last Update Date: 12/11/2017
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):
SHAKUR WALKER (R2DO)
SHAKUR WALKER (R2DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | M/R | Y | 97 | Power Operation | 0 | Hot Standby |
MANUAL REACTOR TRIP IN RESPONSE TO INDICATION OF MULTIPLE DROPPED CONTROL RODS
"While operating at 97% power, the Watts Bar Unit 2 reactor was manually tripped at 0857 EST on December 11, 2017 due to multiple dropped control rods. All control and shutdown bank rods inserted properly in response to the manual reactor trip. All safety systems including Auxiliary Feedwater actuated as designed. The plant is stable with decay heat removal through Auxiliary Feedwater and the Steam Dump System.
"The cause of the dropped rods is being investigated.
"The manual actuation of the Reactor Protection System (RPS) is being reported as a four hour report under 10 CFR 50.72 (b)(2)(iv)(B). The actuation of the Auxiliary Feedwater System (an engineered safety feature) is being reported as an eight hour report under 10 CFR 50.72 (b)(3)(iv)(A).
"The NRC Senior Resident Inspector has been notified for this event."
No safety or relief valves lifted during this event.
"While operating at 97% power, the Watts Bar Unit 2 reactor was manually tripped at 0857 EST on December 11, 2017 due to multiple dropped control rods. All control and shutdown bank rods inserted properly in response to the manual reactor trip. All safety systems including Auxiliary Feedwater actuated as designed. The plant is stable with decay heat removal through Auxiliary Feedwater and the Steam Dump System.
"The cause of the dropped rods is being investigated.
"The manual actuation of the Reactor Protection System (RPS) is being reported as a four hour report under 10 CFR 50.72 (b)(2)(iv)(B). The actuation of the Auxiliary Feedwater System (an engineered safety feature) is being reported as an eight hour report under 10 CFR 50.72 (b)(3)(iv)(A).
"The NRC Senior Resident Inspector has been notified for this event."
No safety or relief valves lifted during this event.