Event Notification Report for September 29, 2024
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
09/28/2024 - 09/29/2024
Power Reactor
Event Number: 57351
Facility: Sequoyah
Region: 2 State: TN
Unit: [1] [] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: Timothy Wood
HQ OPS Officer: Natalie Starfish
Region: 2 State: TN
Unit: [1] [] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: Timothy Wood
HQ OPS Officer: Natalie Starfish
Notification Date: 09/29/2024
Notification Time: 08:40 [ET]
Event Date: 09/29/2024
Event Time: 05:56 [EDT]
Last Update Date: 09/29/2024
Notification Time: 08:40 [ET]
Event Date: 09/29/2024
Event Time: 05:56 [EDT]
Last Update Date: 09/29/2024
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):
Suber, Gregory (R2DO)
Suber, Gregory (R2DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | A/R | Y | 100 | Power Operation | 0 | Hot Standby |
EN Revision Imported Date: 10/1/2024
EN Revision Text: AUTOMATIC REACTOR TRIP DUE TO TURBINE TRIP
The following information was provided by the licensee via phone and email:
"At 05:56 EDT on 09/29/2024, with Unit 1 in Mode 1 at 100 percent power, the reactor automatically tripped due to a turbine trip. The motor driven auxiliary feedwater (MDAFW) level control valves (LCV) for loop 1 failed to respond from the main control room. All others systems responded normally post-trip.
"Operations responded and stabilized the plant. Decay heat is being removed by the auxiliary feedwater (AFW) and steam dump systems. Unit 2 is currently stable in Mode 6 for a maintenance outage and was not affected.
"Due to the reactor protection system actuation while critical, this event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B) and an eight-hour, non-emergency notification per 10 CFR 50.72 (b)(3)(iv)(A) as an event that results in a valid actuation of the AFW system. The AFW system started automatically and is operating as designed with the exception of the MDAFW LCVs for loop 1.
"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."
EN Revision Text: AUTOMATIC REACTOR TRIP DUE TO TURBINE TRIP
The following information was provided by the licensee via phone and email:
"At 05:56 EDT on 09/29/2024, with Unit 1 in Mode 1 at 100 percent power, the reactor automatically tripped due to a turbine trip. The motor driven auxiliary feedwater (MDAFW) level control valves (LCV) for loop 1 failed to respond from the main control room. All others systems responded normally post-trip.
"Operations responded and stabilized the plant. Decay heat is being removed by the auxiliary feedwater (AFW) and steam dump systems. Unit 2 is currently stable in Mode 6 for a maintenance outage and was not affected.
"Due to the reactor protection system actuation while critical, this event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B) and an eight-hour, non-emergency notification per 10 CFR 50.72 (b)(3)(iv)(A) as an event that results in a valid actuation of the AFW system. The AFW system started automatically and is operating as designed with the exception of the MDAFW LCVs for loop 1.
"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."
Agreement State
Event Number: 57354
Rep Org: Louisiana Radiation Protection Div
Licensee: Syngenta Crop Protection, LLC
Region: 4
City: St. Gabriel State: LA
County:
License #: LA-2219-L01
Agreement: Y
Docket:
NRC Notified By: James Pate
HQ OPS Officer: Ian Howard
Licensee: Syngenta Crop Protection, LLC
Region: 4
City: St. Gabriel State: LA
County:
License #: LA-2219-L01
Agreement: Y
Docket:
NRC Notified By: James Pate
HQ OPS Officer: Ian Howard
Notification Date: 09/30/2024
Notification Time: 16:42 [ET]
Event Date: 09/29/2024
Event Time: 00:00 [CDT]
Last Update Date: 09/30/2024
Notification Time: 16:42 [ET]
Event Date: 09/29/2024
Event Time: 00:00 [CDT]
Last Update Date: 09/30/2024
Emergency Class: Non Emergency
10 CFR Section:
Agreement State
10 CFR Section:
Agreement State
Person (Organization):
Gepford, Heather (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
Gepford, Heather (R4DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
AGREEMENT STATE REPORT - STUCK SHUTTERS
The following information was provided by the Louisiana Radiation Protection Division via email:
"This event is considered an equipment failure with open shutters. The failure occurred while Syngenta Crop Protection was performing their required license condition shutter checks on August 29, 2024. There were two nuclear gauges that failed the shutter operational checks.
"The two nuclear gauges are in the failed open shutter position.
"The first gauge is a Texas Nuclear series 5100, model 5189 and serial number 51, with a source activity of 25 mCi [Cs-137] and the second gauge is a RONAN Engineering, model SA1-F37 and serial number 6268CM, with a source activity of 2000 mCi [Cs-137 and Co-60].
"Syngenta Crop Protection is planning to bring a third party to work on or replace the nuclear gauges. BBP Sales will be the third party. Syngenta Crop Protection plans on having BBP Sales out to the facility as soon as possible."
LA Event Report ID Number: LA20240010
The following information was provided by the Louisiana Radiation Protection Division via email:
"This event is considered an equipment failure with open shutters. The failure occurred while Syngenta Crop Protection was performing their required license condition shutter checks on August 29, 2024. There were two nuclear gauges that failed the shutter operational checks.
"The two nuclear gauges are in the failed open shutter position.
"The first gauge is a Texas Nuclear series 5100, model 5189 and serial number 51, with a source activity of 25 mCi [Cs-137] and the second gauge is a RONAN Engineering, model SA1-F37 and serial number 6268CM, with a source activity of 2000 mCi [Cs-137 and Co-60].
"Syngenta Crop Protection is planning to bring a third party to work on or replace the nuclear gauges. BBP Sales will be the third party. Syngenta Crop Protection plans on having BBP Sales out to the facility as soon as possible."
LA Event Report ID Number: LA20240010