Event Notification Report for February 15, 2024
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
02/14/2024 - 02/15/2024
Power Reactor
Event Number: 56970
Facility: Watts Bar
Region: 2 State: TN
Unit: [1] [2] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: Tyson Jones
HQ OPS Officer: Kerby Scales
Region: 2 State: TN
Unit: [1] [2] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: Tyson Jones
HQ OPS Officer: Kerby Scales
Notification Date: 02/16/2024
Notification Time: 02:05 [ET]
Event Date: 02/15/2024
Event Time: 22:24 [EST]
Last Update Date: 02/21/2024
Notification Time: 02:05 [ET]
Event Date: 02/15/2024
Event Time: 22:24 [EST]
Last Update Date: 02/21/2024
Emergency Class: Non Emergency
10 CFR Section:
50.72(b)(3)(iv)(A) - Valid Specif Sys Actuation
10 CFR Section:
50.72(b)(3)(iv)(A) - Valid Specif Sys Actuation
Person (Organization):
Miller, Mark (R2DO)
Miller, Mark (R2DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | Y | 100 | Power Operation | 100 | Power Operation |
| 2 | N | Y | 100 | Power Operation | 100 | Power Operation |
EN Revision Imported Date: 2/22/2024
EN Revision Text: ACTUATION OF EMERGENCY DIESEL GENERATOR SYSTEM
The following information was provided by the licensee via email:
"At 2224 EST on February 15, 2024, with both units 1 and 2 in mode 1 at 100 percent power, an actuation of the emergency diesel generator (EDG) system on 1A-A, 1B-B, and 2B-B EDGs occurred while removing clearances. The 2A-A EDG did not start because it was still under a clearance. The reason for the emergency diesel generator system auto-start was clearance removal sequencing errors. The emergency diesel generator system automatically started as designed when the common emergency start signal was received.
"This event is being reported in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the emergency diesel generator system.
"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."
* * * RETRACTION ON 2/21/2024 AT 1549 EST FROM TYSON JONES TO KAREN COTTON * * *
The following information was provided by the licensee via email:
"In accordance with NUREG-1022, Section 2.8 and Section 4.2.3, Watts Barr is retracting the previous report EN 56970 pursuant to 10 CFR 50.72(b)(3)(iv)(A). The start signal for the 1A-A, 1B-B, and 2B-B emergency diesel generators (EDG)s was from activation of the common emergency start of the 2A-A EDG. The actuation was not from a loss of offsite power (LOOP) to any shutdown board or from any parameters that would initiate a safety injection (SI) signal, for which the EDG is designed to provide a design basis safety function. Also, the starts were not from intentional manual actuation. Starting the EDGs did not make them inoperable and each EDG was able to perform its design safety function.
"The common emergency start relay for each diesel is not safety related. It is an anticipatory and redundant circuit to start other EDGs in the event of a LOOP or SI related to the specific EDG. With the 2A-A EDG out of service, the associated common emergency circuit would not be required to perform any function. The starts were not initiated in response to actual plant conditions or parameters satisfying the requirements for initiation of the system. Since the starts were not initiated via an automatic signal from a LOOP, SI, or traditional operator action, the signal is not a valid actuation in accordance with 10 CFR 50.72(b)(3)(iv)(A). Therefore, EN 56970 is being retracted.
"The NRC Resident Inspector has been notified of this retraction."
Notified R2DO (Miller)
EN Revision Text: ACTUATION OF EMERGENCY DIESEL GENERATOR SYSTEM
The following information was provided by the licensee via email:
"At 2224 EST on February 15, 2024, with both units 1 and 2 in mode 1 at 100 percent power, an actuation of the emergency diesel generator (EDG) system on 1A-A, 1B-B, and 2B-B EDGs occurred while removing clearances. The 2A-A EDG did not start because it was still under a clearance. The reason for the emergency diesel generator system auto-start was clearance removal sequencing errors. The emergency diesel generator system automatically started as designed when the common emergency start signal was received.
"This event is being reported in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the emergency diesel generator system.
"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."
* * * RETRACTION ON 2/21/2024 AT 1549 EST FROM TYSON JONES TO KAREN COTTON * * *
The following information was provided by the licensee via email:
"In accordance with NUREG-1022, Section 2.8 and Section 4.2.3, Watts Barr is retracting the previous report EN 56970 pursuant to 10 CFR 50.72(b)(3)(iv)(A). The start signal for the 1A-A, 1B-B, and 2B-B emergency diesel generators (EDG)s was from activation of the common emergency start of the 2A-A EDG. The actuation was not from a loss of offsite power (LOOP) to any shutdown board or from any parameters that would initiate a safety injection (SI) signal, for which the EDG is designed to provide a design basis safety function. Also, the starts were not from intentional manual actuation. Starting the EDGs did not make them inoperable and each EDG was able to perform its design safety function.
"The common emergency start relay for each diesel is not safety related. It is an anticipatory and redundant circuit to start other EDGs in the event of a LOOP or SI related to the specific EDG. With the 2A-A EDG out of service, the associated common emergency circuit would not be required to perform any function. The starts were not initiated in response to actual plant conditions or parameters satisfying the requirements for initiation of the system. Since the starts were not initiated via an automatic signal from a LOOP, SI, or traditional operator action, the signal is not a valid actuation in accordance with 10 CFR 50.72(b)(3)(iv)(A). Therefore, EN 56970 is being retracted.
"The NRC Resident Inspector has been notified of this retraction."
Notified R2DO (Miller)
Power Reactor
Event Number: 56968
Facility: Callaway
Region: 4 State: MO
Unit: [1] [] []
RX Type: [1] W-4-LP
NRC Notified By: Mike Larson
HQ OPS Officer: Bill Gott
Region: 4 State: MO
Unit: [1] [] []
RX Type: [1] W-4-LP
NRC Notified By: Mike Larson
HQ OPS Officer: Bill Gott
Notification Date: 02/15/2024
Notification Time: 05:45 [ET]
Event Date: 02/15/2024
Event Time: 02:47 [CST]
Last Update Date: 02/15/2024
Notification Time: 05:45 [ET]
Event Date: 02/15/2024
Event Time: 02:47 [CST]
Last Update Date: 02/15/2024
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):
Vossmar, Patricia (R4DO)
Vossmar, Patricia (R4DO)
| 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 |
AUTOMATIC TURBINE TRIP/REACTOR TRIP
The following information was provided by the licensee via email:
"At 0247 CST on 2/15/2024, Callaway Plant was in mode 1 at approximately 100 percent power when a turbine trip and reactor trip occurred. All safety systems responded as expected with the exception of an indication issue on the feedwater isolation valves, which were confirmed closed. A valid feedwater isolation signal and auxiliary feedwater actuation signal were also received as a result of the reactor trip. The plant is being maintained stable in mode 3.
"All control rods fully inserted from the reactor trip signal and decay heat is being removed via the auxiliary feedwater system and steam dumps.
"The NRC Resident Inspector was notified."
The following information was provided by the licensee via email:
"At 0247 CST on 2/15/2024, Callaway Plant was in mode 1 at approximately 100 percent power when a turbine trip and reactor trip occurred. All safety systems responded as expected with the exception of an indication issue on the feedwater isolation valves, which were confirmed closed. A valid feedwater isolation signal and auxiliary feedwater actuation signal were also received as a result of the reactor trip. The plant is being maintained stable in mode 3.
"All control rods fully inserted from the reactor trip signal and decay heat is being removed via the auxiliary feedwater system and steam dumps.
"The NRC Resident Inspector was notified."
Power Reactor
Event Number: 57077
Facility: Watts Bar
Region: 2 State: TN
Unit: [1] [2] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: Tony Pate
HQ OPS Officer: Sam Colvard
Region: 2 State: TN
Unit: [1] [2] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: Tony Pate
HQ OPS Officer: Sam Colvard
Notification Date: 04/15/2024
Notification Time: 14:38 [ET]
Event Date: 02/15/2024
Event Time: 22:24 [EDT]
Last Update Date: 04/15/2024
Notification Time: 14:38 [ET]
Event Date: 02/15/2024
Event Time: 22:24 [EDT]
Last Update Date: 04/15/2024
Emergency Class: Non Emergency
10 CFR Section:
50.73(a)(1) - Invalid Specif System Actuation
10 CFR Section:
50.73(a)(1) - Invalid Specif System Actuation
Person (Organization):
Miller, Mark (R2DO)
Miller, Mark (R2DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | Y | 100 | Power Operation | 100 | Power Operation |
| 2 | N | Y | 100 | Power Operation | 100 | Power Operation |
INVALID ACTUATION OF EMERGENCY DIESEL GENERATORS
The following information was provided by the licensee via email:
"At 2224 EST on February 15, 2024, with both units 1 and 2 in Mode 1 at 100 percent power, an invalid start of the emergency diesel generator (EDG) system on 1A-A, 1B-B, and 2B-B EDGs occurred while removing clearances. The 2A-A EDG did not start because it was still under a clearance. The 1A-A, 1B-B, and 2B-B EDGs started and functioned successfully.
"The start signal for the 1A-A, 1B-B, and 2B-B EDGs was generated from the common emergency start of the 2A-A EDG. The signal was not from a loss of offsite power (LOOP) to any shutdown board or from any parameters that would initiate a safety injection (SI) signal, for which the EDG is designed to provide a design basis safety function. Also, the starts were not from intentional manual actuation. Starting the EDGs did not make them inoperable and each EDG was able to perform its design [basis] safety function.
"The common emergency start relay for each diesel is not safety related. It is an anticipatory and redundant circuit to start other EDGs in the event of a LOOP or SI related to the specific EDG. With the 2A-A EDG out of service, the associated common emergency circuit would not be required to perform any function. The starts were not initiated in response to actual plant conditions or parameters satisfying the requirements for initiation of the system.
"This event was originally reported under EN 56970 on February 16, 2024, at 0205 EST in accordance with 10 CFR 50.72(b)(3) (iv)(A) as an event that results in a valid actuation of the emergency diesel generator system. This EN was retracted on February 21, 2024, at 1549 EST.
"This event is being reported in accordance with 10 CFR 50.73(a)(1) and 10 CFR 50.73(a)(2)(iv)(A) as an event that results in an invalid actuation of the emergency diesel generator system.
"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."
The following information was provided by the licensee via email:
"At 2224 EST on February 15, 2024, with both units 1 and 2 in Mode 1 at 100 percent power, an invalid start of the emergency diesel generator (EDG) system on 1A-A, 1B-B, and 2B-B EDGs occurred while removing clearances. The 2A-A EDG did not start because it was still under a clearance. The 1A-A, 1B-B, and 2B-B EDGs started and functioned successfully.
"The start signal for the 1A-A, 1B-B, and 2B-B EDGs was generated from the common emergency start of the 2A-A EDG. The signal was not from a loss of offsite power (LOOP) to any shutdown board or from any parameters that would initiate a safety injection (SI) signal, for which the EDG is designed to provide a design basis safety function. Also, the starts were not from intentional manual actuation. Starting the EDGs did not make them inoperable and each EDG was able to perform its design [basis] safety function.
"The common emergency start relay for each diesel is not safety related. It is an anticipatory and redundant circuit to start other EDGs in the event of a LOOP or SI related to the specific EDG. With the 2A-A EDG out of service, the associated common emergency circuit would not be required to perform any function. The starts were not initiated in response to actual plant conditions or parameters satisfying the requirements for initiation of the system.
"This event was originally reported under EN 56970 on February 16, 2024, at 0205 EST in accordance with 10 CFR 50.72(b)(3) (iv)(A) as an event that results in a valid actuation of the emergency diesel generator system. This EN was retracted on February 21, 2024, at 1549 EST.
"This event is being reported in accordance with 10 CFR 50.73(a)(1) and 10 CFR 50.73(a)(2)(iv)(A) as an event that results in an invalid actuation of the emergency diesel generator system.
"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
Part 21
Event Number: 57079
Rep Org: Paragon Energy Solutions
Licensee:
Region: 2
City: Fort Worth State: TX
County:
License #:
Agreement: N
Docket:
NRC Notified By: Richard Knott
HQ OPS Officer: Bill Gott
Licensee:
Region: 2
City: Fort Worth State: TX
County:
License #:
Agreement: N
Docket:
NRC Notified By: Richard Knott
HQ OPS Officer: Bill Gott
Notification Date: 04/16/2024
Notification Time: 23:29 [ET]
Event Date: 02/15/2024
Event Time: 00:00 [CDT]
Last Update Date: 07/27/2024
Notification Time: 23:29 [ET]
Event Date: 02/15/2024
Event Time: 00:00 [CDT]
Last Update Date: 07/27/2024
Emergency Class: Non Emergency
10 CFR Section:
21.21(a)(2) - Interim Eval Of Deviation
10 CFR Section:
21.21(a)(2) - Interim Eval Of Deviation
Person (Organization):
Franke, Mark (R2DO)
Part 21/50.55 Reactors (EMAIL)
Franke, Mark (R2DO)
Part 21/50.55 Reactors (EMAIL)
EN Revision Imported Date: 7/29/2024
EN Revision Text: INITIAL PART 21 REPORT - POTENTIAL DEFECT WITH CIRCUIT BREAKER
The following information was provided by the licensee via email:
"Pursuant to 10CFR 21.21 (a)(2), Paragon Energy Solutions, LLC is providing this interim notification of ongoing analysis for Part 21 reportability of a potential defect with a Schneider Electric Medium Voltage VR Type Circuit Breaker Part Number V5D4133Y000.
"On February 15, 2024, Paragon completed initial documentation of a potential defect with the subject circuit breaker in which Duke-Oconee had identified failure to close on demand or delayed operation to close with extended application of the remote closing signal. Since the primary safety function of the circuit breaker is to close and maintain continuity of power to downstream loads, failure to close could potentially contribute to a substantial safety hazard.
"This is the first reported instance of this failure mode, and Paragon suspects the issue to be related to aging of the circuit breaker's lubrication. Paragon requires more time to complete testing and analysis to confirm the failure mode and determine reportability.
"Date when evaluation is expected to be complete: 5/03/2024."
Affected licensee: Oconee. Paragon is currently evaluating the extent of condition as it pertains to other plants and equipment that may utilize the same or similar circuit breakers.
* * * UPDATE ON 05/02/24 FROM R. KNOTT TO T. HERRITY VIA EMAIL AND PHONE CALL * * *
Due to inconclusive results, the completion date of the testing is revised to 05/31/2024.
Notified R2DO (Miller) and Part 21/50.55 Reactors (email).
* * * UPDATE ON 5/31/2024 AT 1534 EDT FROM RICHARD KNOTT TO ERNEST WEST * * *
The following is a synopsis of the updated information received:
The only known affected licensee is Oconee. Paragon is evaluating if the issue pertains to other equipment or plants.
Paragon has conducted additional testing with the original equipment manufacturer, Schneider Electric, but will require more time to complete their evaluation. Evaluation is expected to be complete by 6/30/2024.
Other circuit breaker types that may be affected are:
5GSB2-250-1200 (uses KVR type element)
5GSB2-350-1200 (uses KVR type element)
5GSB3-350-1200 (uses KVR type element)
5GSB3-350-2000 (uses KVR type element)
Paragon recommends licensees with the breaker types listed above monitor for failure to close on demand or delayed. If any improper operation is found, report it to Paragon for evaluation.
Contact Information:
Richard Knott
Vice President Quality Assurance
Paragon Energy Solutions
817-284-0077
rknott@paragones.com
Notified R2DO (Franke) and Part 21/50.55 Reactors (email).
* * * UPDATE ON 6/29/2024 AT 1137 EDT FROM RICHARD KNOTT TO ERNEST WEST * * *
The following is a synopsis of the updated information received:
Paragon Energy Solutions has provided a new expected date for completion of their evaluation: 7/28/2024.
The only known affected licensee remains Oconee.
Notified R2DO (Suggs) and Part 21/50.55 Reactors (email).
* * * RETRACTION ON 7/27/2024 AT 0836 EDT FROM RICHARD KNOTT TO KAREN COTTON * * *
The following is an excerpt from a Part 21 final update received via email:
"Paragon has been working closely with OEM (Schneider Electric) to conduct the failure analysis. After extensive inspection and testing by Schneider Electric, the condition has not been able to be recreated following cleaning and relubrication activities, nor has any non-conformances with breaker parts and materials been identified that would cause delayed closing of the breaker mechanism. Paragon has reviewed the final OEM analysis report and concludes the issue exhibited with this breaker is related to lubrication maintenance and not the result of any defect in design or manufacturing. Paragon will be updating instruction manuals associated with this breaker element for all clients recommending more frequent cleaning, relubricating, and cycling frequencies.
"Based on the evaluation conducted, Paragon has concluded the deviation discussed above is not reportable per 10CFR Part 21."
Notified R2DO (Coovert) and Part 21/50.55 Reactors (email).
EN Revision Text: INITIAL PART 21 REPORT - POTENTIAL DEFECT WITH CIRCUIT BREAKER
The following information was provided by the licensee via email:
"Pursuant to 10CFR 21.21 (a)(2), Paragon Energy Solutions, LLC is providing this interim notification of ongoing analysis for Part 21 reportability of a potential defect with a Schneider Electric Medium Voltage VR Type Circuit Breaker Part Number V5D4133Y000.
"On February 15, 2024, Paragon completed initial documentation of a potential defect with the subject circuit breaker in which Duke-Oconee had identified failure to close on demand or delayed operation to close with extended application of the remote closing signal. Since the primary safety function of the circuit breaker is to close and maintain continuity of power to downstream loads, failure to close could potentially contribute to a substantial safety hazard.
"This is the first reported instance of this failure mode, and Paragon suspects the issue to be related to aging of the circuit breaker's lubrication. Paragon requires more time to complete testing and analysis to confirm the failure mode and determine reportability.
"Date when evaluation is expected to be complete: 5/03/2024."
Affected licensee: Oconee. Paragon is currently evaluating the extent of condition as it pertains to other plants and equipment that may utilize the same or similar circuit breakers.
* * * UPDATE ON 05/02/24 FROM R. KNOTT TO T. HERRITY VIA EMAIL AND PHONE CALL * * *
Due to inconclusive results, the completion date of the testing is revised to 05/31/2024.
Notified R2DO (Miller) and Part 21/50.55 Reactors (email).
* * * UPDATE ON 5/31/2024 AT 1534 EDT FROM RICHARD KNOTT TO ERNEST WEST * * *
The following is a synopsis of the updated information received:
The only known affected licensee is Oconee. Paragon is evaluating if the issue pertains to other equipment or plants.
Paragon has conducted additional testing with the original equipment manufacturer, Schneider Electric, but will require more time to complete their evaluation. Evaluation is expected to be complete by 6/30/2024.
Other circuit breaker types that may be affected are:
5GSB2-250-1200 (uses KVR type element)
5GSB2-350-1200 (uses KVR type element)
5GSB3-350-1200 (uses KVR type element)
5GSB3-350-2000 (uses KVR type element)
Paragon recommends licensees with the breaker types listed above monitor for failure to close on demand or delayed. If any improper operation is found, report it to Paragon for evaluation.
Contact Information:
Richard Knott
Vice President Quality Assurance
Paragon Energy Solutions
817-284-0077
rknott@paragones.com
Notified R2DO (Franke) and Part 21/50.55 Reactors (email).
* * * UPDATE ON 6/29/2024 AT 1137 EDT FROM RICHARD KNOTT TO ERNEST WEST * * *
The following is a synopsis of the updated information received:
Paragon Energy Solutions has provided a new expected date for completion of their evaluation: 7/28/2024.
The only known affected licensee remains Oconee.
Notified R2DO (Suggs) and Part 21/50.55 Reactors (email).
* * * RETRACTION ON 7/27/2024 AT 0836 EDT FROM RICHARD KNOTT TO KAREN COTTON * * *
The following is an excerpt from a Part 21 final update received via email:
"Paragon has been working closely with OEM (Schneider Electric) to conduct the failure analysis. After extensive inspection and testing by Schneider Electric, the condition has not been able to be recreated following cleaning and relubrication activities, nor has any non-conformances with breaker parts and materials been identified that would cause delayed closing of the breaker mechanism. Paragon has reviewed the final OEM analysis report and concludes the issue exhibited with this breaker is related to lubrication maintenance and not the result of any defect in design or manufacturing. Paragon will be updating instruction manuals associated with this breaker element for all clients recommending more frequent cleaning, relubricating, and cycling frequencies.
"Based on the evaluation conducted, Paragon has concluded the deviation discussed above is not reportable per 10CFR Part 21."
Notified R2DO (Coovert) and Part 21/50.55 Reactors (email).