Event Notification Report for October 15, 2021
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
10/14/2021 - 10/15/2021
EVENT NUMBERS
55526
55526
Power Reactor
Event Number: 55526
Facility: Diablo Canyon
Region: 4 State: CA
Unit: [2] [] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: Meagan Nolan
HQ OPS Officer: Kerby Scales
Region: 4 State: CA
Unit: [2] [] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: Meagan Nolan
HQ OPS Officer: Kerby Scales
Notification Date: 10/15/2021
Notification Time: 23:28 [ET]
Event Date: 10/15/2021
Event Time: 17:49 [PDT]
Last Update Date: 10/15/2021
Notification Time: 23:28 [ET]
Event Date: 10/15/2021
Event Time: 17:49 [PDT]
Last Update Date: 10/15/2021
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):
ALEXANDER, RYAN (R4)
ALEXANDER, RYAN (R4)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | M/R | Y | 90 | Power Operation | 0 | Hot Standby |
EN Revision Imported Date: 11/15/2021
EN Revision Text: MANUAL REACTOR TRIP AND AUTOMATIC AUXILIARY FEEDWATER ACTUATION
"On October 15, 2021, at 1749 PDT with Diablo Canyon Power Plant Unit 2 operating at approximately 90 percent power, the reactor was manually tripped in accordance with plant procedures due to increasing water level in feedwater heater 2-5B. The reactor trip was uncomplicated and the Auxiliary Feedwater system started as expected. The plant is stable in Mode 3.
"This notification is being made in accordance the requirements of 10 CFR 50.72(b)(2)(iv)(B) as a manual actuation of the reactor protection system and 10 CFR 50.72(b)(3)(iv)(A) as an automatic actuation of a specified safety system.
"The cause of the increased feedwater level is under investigation. There was no impact to the health and safety of the public or plant personnel.
"The Resident Inspector has been notified."
EN Revision Text: MANUAL REACTOR TRIP AND AUTOMATIC AUXILIARY FEEDWATER ACTUATION
"On October 15, 2021, at 1749 PDT with Diablo Canyon Power Plant Unit 2 operating at approximately 90 percent power, the reactor was manually tripped in accordance with plant procedures due to increasing water level in feedwater heater 2-5B. The reactor trip was uncomplicated and the Auxiliary Feedwater system started as expected. The plant is stable in Mode 3.
"This notification is being made in accordance the requirements of 10 CFR 50.72(b)(2)(iv)(B) as a manual actuation of the reactor protection system and 10 CFR 50.72(b)(3)(iv)(A) as an automatic actuation of a specified safety system.
"The cause of the increased feedwater level is under investigation. There was no impact to the health and safety of the public or plant personnel.
"The Resident Inspector has been notified."