Event Notification Report for March 21, 2024
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
03/20/2024 - 03/21/2024
Non-Agreement State
Event Number: 57044
Rep Org: US Army
Licensee: US Army
Region: 3
City: Detroit State: MI
County:
License #: 21-32838-01
Agreement: N
Docket:
NRC Notified By: Nathan Krzyaniak
HQ OPS Officer: Bill Gott
Licensee: US Army
Region: 3
City: Detroit State: MI
County:
License #: 21-32838-01
Agreement: N
Docket:
NRC Notified By: Nathan Krzyaniak
HQ OPS Officer: Bill Gott
Notification Date: 03/22/2024
Notification Time: 08:35 [ET]
Event Date: 03/21/2024
Event Time: 17:00 [EDT]
Last Update Date: 03/22/2024
Notification Time: 08:35 [ET]
Event Date: 03/21/2024
Event Time: 17:00 [EDT]
Last Update Date: 03/22/2024
Emergency Class: Non Emergency
10 CFR Section:
20.2201(a)(1)(i) - Lost/Stolen LNM>1000x
10 CFR Section:
20.2201(a)(1)(i) - Lost/Stolen LNM>1000x
Person (Organization):
Hills, David (R3DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
ILTAB (EMAIL)
Hills, David (R3DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
ILTAB (EMAIL)
LOST TRITIUM AIMING POST LIGHTS
The following information was provided by the licensee:
At around 1700 CDT on March 21, 2024, the Detroit Army Arsenal's radiation safety officer (RSO) noticed a picture of two Army M58 Aiming Post Lights, which typically contain 5 Ci of tritium each, on a Reddit sub-group. The post indicated that the devices were a "going away gift" from the Army, and that the individual was no longer in the Army. The sealed sources appeared to be intact, but the RSO could not see the serial numbers.
The RSO plans on reporting this to his chain of command and to the Army Criminal Investigative Service.
THIS MATERIAL EVENT CONTAINS A 'Less than Cat 3' LEVEL OF RADIOACTIVE MATERIAL
Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. For additional information go to http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf
The following information was provided by the licensee:
At around 1700 CDT on March 21, 2024, the Detroit Army Arsenal's radiation safety officer (RSO) noticed a picture of two Army M58 Aiming Post Lights, which typically contain 5 Ci of tritium each, on a Reddit sub-group. The post indicated that the devices were a "going away gift" from the Army, and that the individual was no longer in the Army. The sealed sources appeared to be intact, but the RSO could not see the serial numbers.
The RSO plans on reporting this to his chain of command and to the Army Criminal Investigative Service.
THIS MATERIAL EVENT CONTAINS A 'Less than Cat 3' LEVEL OF RADIOACTIVE MATERIAL
Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. For additional information go to http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
Power Reactor
Event Number: 57042
Facility: Waterford
Region: 4 State: LA
Unit: [3] [] []
RX Type: [3] CE
NRC Notified By: Nathan Marsh
HQ OPS Officer: Bill Gott
Region: 4 State: LA
Unit: [3] [] []
RX Type: [3] CE
NRC Notified By: Nathan Marsh
HQ OPS Officer: Bill Gott
Notification Date: 03/22/2024
Notification Time: 01:17 [ET]
Event Date: 03/21/2024
Event Time: 23:37 [CDT]
Last Update Date: 03/27/2024
Notification Time: 01:17 [ET]
Event Date: 03/21/2024
Event Time: 23:37 [CDT]
Last Update Date: 03/27/2024
Emergency Class: Unusual Event
10 CFR Section:
50.72(a) (1) (i) - Emergency Declared 50.72(b)(2)(iv)(B) - RPS Actuation - Critical 50.72(b)(3)(iv)(A) - Valid Specif Sys Actuation
10 CFR Section:
50.72(a) (1) (i) - Emergency Declared 50.72(b)(2)(iv)(B) - RPS Actuation - Critical 50.72(b)(3)(iv)(A) - Valid Specif Sys Actuation
Person (Organization):
Heather Gepford (R4DO)
John Monninger (R4)
Andrea Veil (NRR)
Grant, Jeffery (IR)
Victor Dricks (R4 PAO)
Heather Gepford (R4DO)
John Monninger (R4)
Andrea Veil (NRR)
Grant, Jeffery (IR)
Victor Dricks (R4 PAO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 3 | A/R | Y | 98 | Power Operation | 0 | Hot Standby |
EN Revision Imported Date: 3/28/2024
EN Revision Text: NOTIFICATION OF UNUSUAL EVENT DUE TO FIRE IN THE PROTECTED AREA
The following information was provided by the licensee:
A Notification of Unusual Event, HU4.4 (see note below) was declared based a fire in the protected area requiring off site assistance to extinguish. The fire was in the main transformer yard. The fire was detected at 2328 CDT on March 21, 2024, and the fire was declared out at 0009 CDT on at March 22, 2024. An automatic reactor trip was initiated due to a loss of offsite power to the "B" train and a failure to automatically transfer from unit auxiliary transformer "B" to startup transformer "B."
The licensee notified State and local authorities and the NRC Resident Inspector.
The NRC remained in Normal.
Notified DHS SWO, FEMA Operations Center, CISA Central, FEMA NWC (email), CWMD Watch Desk (email), DHS NRCC THD Desk (email), and DHS Nuclear SSA (email).
NOTE: Due to a typographical error initiating condition HU4.1 was initially recorded for the event. The correct initiating condition is HU4.4 as now shown.
* * * UPDATE AT 0345 EDT ON 03/22/24 FROM LARRY GONSALES TO BILL GOTT * * *
The licensee terminated the Notification of Unusual Event at 0221 CDT on 3/22/24.
The licensee notified the NRC Resident Inspector.
Notified R4DO (Gepford), IR-MOC (Grant), NRR-EO (Felts), DHS-SWO, FEMA Operations Center, CISA Central, FEMA NWC (email), CWMD Watch Desk (email), DHS NRCC THD Desk (email), and DHS Nuclear SSA (email).
* * * UPDATE AT 0420EDT ON 03/22/24 FROM JOHN LEWIS TO BILL GOTT * * *
RPS ACTUATION
The following information was provided by the licensee via email:
"On March 21, 2024, at 2328 CDT, Waterford 3 Steam Electric Station, Unit 3 was operating at 98 percent power when an automatic reactor trip was initiated due to a loss of offsite power to the 'B' train and a failure to automatically transfer from unit auxiliary transformer 'B' to startup transformer 'B.'
"Emergency feedwater actuation signal 2 (EFAS), safety injection actuation signal (ECCS), containment isolation actuation signal and emergency diesel generators automatically actuated. The unit is currently stable in Mode 3. All control rods fully inserted and all other plant equipment functioned as expected. Forced circulation remains with one reactor coolant pump per loop running. Decay heat removal is via the main condenser. 'A' train safety bus is being supplied by off-site power, and 'B' train safety bus is being supplied by emergency diesel generator 'B.'
"Following the loss of offsite power to the 'B' train, it was reported that main transformer 'B' and startup transformer 'B' were both on fire. The Emergency Director declared an Unusual Event at time 2337 CDT. The fire was reported extinguished at 0009 CDT on March 22, 2024, and the Unusual Event was terminated at 0221 CDT on March 22, 2024. Offsite assistance was requested. The local fire department responded to the site but the fire was extinguished by the on-shift fire brigade. NRC Region IV management was contacted regarding the emergency plan entry at 0030 CDT on March 22, 2024.
"This event is being reported as a 4-hour non-emergency notification in accordance with 10 CFR 50.72(b)(2)(iv)(B) as an actuation of the reactor protection system (RPS) when the reactor is critical and as an 8-hour non-emergency notification in accordance with 10 CFR 50.72(b)(3)(iv)(A) as valid actuation of the EFW system, ECCS, Containment Isolation and Emergency Diesel Generators.
"The NRC Resident Inspector has been notified."
Notified R4DO (Gepford)
* * * RETRACTION OF NOTICE OF UNUSUAL EVENT FROM ON 03/26/24 AT 1721 FROM L. BROWN TO K. COTTON * * *
"The initial notification in event notice #57042 by Waterford Steam Electric Station, Unit 3, reported a Notice Of Unusual Event (NOUE) emergency declaration due to a fire in the protected area requiring off site support to extinguish. The basis for retraction of the initial emergency notification is that this event did not meet the definition of a fire in the protected area that requires off site support to extinguish. Guidance provided in Nuclear Energy Institute (NEI) 99-01, Rev. 6 and implemented in Waterford's Emergency Plan procedure, initiating Condition HU4.4 states, 'The dispatch of an offsite firefighting agency to the site requires an emergency declaration only if it is needed to actively support firefighting efforts because the fire is beyond the capability of the Fire Brigade to extinguish.' (NOTE: The Initial Notification Form sent from the Control Room at 2341 CDT on March 21, 2024, requested by and provided to the NRC Headquarter Operations Center via e-mail at 0302 CDT on March 22, 2024, stated that the Emergency Classification had been made on Initiating Condition HU4.4 rather than HU4.1)"
"When the event occurred on March 21, 2024, the Emergency Director declared an Unusual Event at 2337 CDT and requested offsite support based on the information available at that time including the initial assessment by the fire brigade leader and expected need for offsite support to extinguish the fire. As reported in the 0420 EDT update on March 22, 2024, the fire was reported extinguished at 0009 CDT on March 22, 2024, by the Waterford Fire Brigade without the need of offsite support."
Notified R4DO (Kellar).
* * * UPDATE AT 1209 EDT ON 03/27/24 FROM JOHN LEWIS TO KAREN COTTON * * *
"The initial notification in EN 57042 by Waterford Steam Electric Station, Unit 3, reported an emergency declaration of an Unusual Event due to a fire in the protected area requiring off site support to extinguish. The basis for the update to the initial notification is that this event did not meet the definition of a Fire in the Protected Area that requires offsite support to extinguish. As provided in NEI 99-01, Rev. 6 and implemented in Waterford's emergency plan procedure, initiating condition HU4.4 states, 'The dispatch of an offsite firefighting agency to the site requires an emergency declaration only if it is needed to actively support firefighting efforts because the fire is beyond the capability of the Fire Brigade to extinguish.' Additionally, EAL 4.1 for a fire not extinguished within 15 minutes of detection in any Table H-1 fire area was not applicable because the fire did not occur in a Table H-1 fire area.
"When the event occurred on March 21, 2024, the Emergency Director declared an Unusual Event at 2337 CDT and requested offsite support based on the information available at that time including the initial assessment by the fire brigade leader and expected need for offsite support to extinguish the fire. As reported in the 0420 EDT update on March 22, 2024, the fire was reported extinguished at 0009 CDT on March 22, 2024, by the Waterford Fire Brigade without the need of offsite support.
"(NOTE: The Initial Notification Form sent from the Control Room at 2341 CDT on March 21, 2024, requested by and provided to the Headquarters Operation Center via e-mail at 0302 CDT on March 22, 2024, stated that the emergency classification had been made on initiating condition HU4.4 rather than HU4.1)
"In accordance with NRC Approved guidance in FAQ 21-02 (ML21117A104), Waterford 3 is retracting the initial event notification made at 0117 EDT on March 22, 2024. The remaining events that were reported in EN 57042 as a 4-hour non-emergency notification in accordance with 10 CFR 50.72(b)(2)(iv)(B) as an actuation of the reactor protection system (RPS) when the reactor is critical and as an 8-hour non-emergency notification in accordance with 10 CFR 50.72(b)(3)(iv)(A) as valid actuation of the EFW (emergency feedwater) system, ECCS (emergency core cooling system), containment isolation and emergency diesel generators are still applicable and require no additional update at this time."
The licensee also provided a site map.
Notified R4DO (Kellar)
EN Revision Text: NOTIFICATION OF UNUSUAL EVENT DUE TO FIRE IN THE PROTECTED AREA
The following information was provided by the licensee:
A Notification of Unusual Event, HU4.4 (see note below) was declared based a fire in the protected area requiring off site assistance to extinguish. The fire was in the main transformer yard. The fire was detected at 2328 CDT on March 21, 2024, and the fire was declared out at 0009 CDT on at March 22, 2024. An automatic reactor trip was initiated due to a loss of offsite power to the "B" train and a failure to automatically transfer from unit auxiliary transformer "B" to startup transformer "B."
The licensee notified State and local authorities and the NRC Resident Inspector.
The NRC remained in Normal.
Notified DHS SWO, FEMA Operations Center, CISA Central, FEMA NWC (email), CWMD Watch Desk (email), DHS NRCC THD Desk (email), and DHS Nuclear SSA (email).
NOTE: Due to a typographical error initiating condition HU4.1 was initially recorded for the event. The correct initiating condition is HU4.4 as now shown.
* * * UPDATE AT 0345 EDT ON 03/22/24 FROM LARRY GONSALES TO BILL GOTT * * *
The licensee terminated the Notification of Unusual Event at 0221 CDT on 3/22/24.
The licensee notified the NRC Resident Inspector.
Notified R4DO (Gepford), IR-MOC (Grant), NRR-EO (Felts), DHS-SWO, FEMA Operations Center, CISA Central, FEMA NWC (email), CWMD Watch Desk (email), DHS NRCC THD Desk (email), and DHS Nuclear SSA (email).
* * * UPDATE AT 0420EDT ON 03/22/24 FROM JOHN LEWIS TO BILL GOTT * * *
RPS ACTUATION
The following information was provided by the licensee via email:
"On March 21, 2024, at 2328 CDT, Waterford 3 Steam Electric Station, Unit 3 was operating at 98 percent power when an automatic reactor trip was initiated due to a loss of offsite power to the 'B' train and a failure to automatically transfer from unit auxiliary transformer 'B' to startup transformer 'B.'
"Emergency feedwater actuation signal 2 (EFAS), safety injection actuation signal (ECCS), containment isolation actuation signal and emergency diesel generators automatically actuated. The unit is currently stable in Mode 3. All control rods fully inserted and all other plant equipment functioned as expected. Forced circulation remains with one reactor coolant pump per loop running. Decay heat removal is via the main condenser. 'A' train safety bus is being supplied by off-site power, and 'B' train safety bus is being supplied by emergency diesel generator 'B.'
"Following the loss of offsite power to the 'B' train, it was reported that main transformer 'B' and startup transformer 'B' were both on fire. The Emergency Director declared an Unusual Event at time 2337 CDT. The fire was reported extinguished at 0009 CDT on March 22, 2024, and the Unusual Event was terminated at 0221 CDT on March 22, 2024. Offsite assistance was requested. The local fire department responded to the site but the fire was extinguished by the on-shift fire brigade. NRC Region IV management was contacted regarding the emergency plan entry at 0030 CDT on March 22, 2024.
"This event is being reported as a 4-hour non-emergency notification in accordance with 10 CFR 50.72(b)(2)(iv)(B) as an actuation of the reactor protection system (RPS) when the reactor is critical and as an 8-hour non-emergency notification in accordance with 10 CFR 50.72(b)(3)(iv)(A) as valid actuation of the EFW system, ECCS, Containment Isolation and Emergency Diesel Generators.
"The NRC Resident Inspector has been notified."
Notified R4DO (Gepford)
* * * RETRACTION OF NOTICE OF UNUSUAL EVENT FROM ON 03/26/24 AT 1721 FROM L. BROWN TO K. COTTON * * *
"The initial notification in event notice #57042 by Waterford Steam Electric Station, Unit 3, reported a Notice Of Unusual Event (NOUE) emergency declaration due to a fire in the protected area requiring off site support to extinguish. The basis for retraction of the initial emergency notification is that this event did not meet the definition of a fire in the protected area that requires off site support to extinguish. Guidance provided in Nuclear Energy Institute (NEI) 99-01, Rev. 6 and implemented in Waterford's Emergency Plan procedure, initiating Condition HU4.4 states, 'The dispatch of an offsite firefighting agency to the site requires an emergency declaration only if it is needed to actively support firefighting efforts because the fire is beyond the capability of the Fire Brigade to extinguish.' (NOTE: The Initial Notification Form sent from the Control Room at 2341 CDT on March 21, 2024, requested by and provided to the NRC Headquarter Operations Center via e-mail at 0302 CDT on March 22, 2024, stated that the Emergency Classification had been made on Initiating Condition HU4.4 rather than HU4.1)"
"When the event occurred on March 21, 2024, the Emergency Director declared an Unusual Event at 2337 CDT and requested offsite support based on the information available at that time including the initial assessment by the fire brigade leader and expected need for offsite support to extinguish the fire. As reported in the 0420 EDT update on March 22, 2024, the fire was reported extinguished at 0009 CDT on March 22, 2024, by the Waterford Fire Brigade without the need of offsite support."
Notified R4DO (Kellar).
* * * UPDATE AT 1209 EDT ON 03/27/24 FROM JOHN LEWIS TO KAREN COTTON * * *
"The initial notification in EN 57042 by Waterford Steam Electric Station, Unit 3, reported an emergency declaration of an Unusual Event due to a fire in the protected area requiring off site support to extinguish. The basis for the update to the initial notification is that this event did not meet the definition of a Fire in the Protected Area that requires offsite support to extinguish. As provided in NEI 99-01, Rev. 6 and implemented in Waterford's emergency plan procedure, initiating condition HU4.4 states, 'The dispatch of an offsite firefighting agency to the site requires an emergency declaration only if it is needed to actively support firefighting efforts because the fire is beyond the capability of the Fire Brigade to extinguish.' Additionally, EAL 4.1 for a fire not extinguished within 15 minutes of detection in any Table H-1 fire area was not applicable because the fire did not occur in a Table H-1 fire area.
"When the event occurred on March 21, 2024, the Emergency Director declared an Unusual Event at 2337 CDT and requested offsite support based on the information available at that time including the initial assessment by the fire brigade leader and expected need for offsite support to extinguish the fire. As reported in the 0420 EDT update on March 22, 2024, the fire was reported extinguished at 0009 CDT on March 22, 2024, by the Waterford Fire Brigade without the need of offsite support.
"(NOTE: The Initial Notification Form sent from the Control Room at 2341 CDT on March 21, 2024, requested by and provided to the Headquarters Operation Center via e-mail at 0302 CDT on March 22, 2024, stated that the emergency classification had been made on initiating condition HU4.4 rather than HU4.1)
"In accordance with NRC Approved guidance in FAQ 21-02 (ML21117A104), Waterford 3 is retracting the initial event notification made at 0117 EDT on March 22, 2024. The remaining events that were reported in EN 57042 as a 4-hour non-emergency notification in accordance with 10 CFR 50.72(b)(2)(iv)(B) as an actuation of the reactor protection system (RPS) when the reactor is critical and as an 8-hour non-emergency notification in accordance with 10 CFR 50.72(b)(3)(iv)(A) as valid actuation of the EFW (emergency feedwater) system, ECCS (emergency core cooling system), containment isolation and emergency diesel generators are still applicable and require no additional update at this time."
The licensee also provided a site map.
Notified R4DO (Kellar)
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
Power Reactor
Event Number: 57043
Facility: Callaway
Region: 4 State: MO
Unit: [1] [] []
RX Type: [1] W-4-LP
NRC Notified By: Greg Cizin
HQ OPS Officer: Bill Gott
Region: 4 State: MO
Unit: [1] [] []
RX Type: [1] W-4-LP
NRC Notified By: Greg Cizin
HQ OPS Officer: Bill Gott
Notification Date: 03/22/2024
Notification Time: 01:46 [ET]
Event Date: 03/21/2024
Event Time: 20:56 [CDT]
Last Update Date: 04/25/2024
Notification Time: 01:46 [ET]
Event Date: 03/21/2024
Event Time: 20:56 [CDT]
Last Update Date: 04/25/2024
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):
Gepford, Heather (R4DO)
Gepford, Heather (R4DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | Y | 100 | Power Operation | 100 | Power Operation |
EN Revision Imported Date: 4/26/2024
EN Revision Text: AUTOMATIC TURBINE DRIVEN AUXILIARY FEEDWATER PUMP ACTUATION
The following information was provided by the licensee via email:
"At 2056 on 3/21/24, Callaway Plant was in Mode 1 at approximately 100 percent power when an automatic start of the turbine driven auxiliary feedwater pump occurred. The event occurred while restoring inverter NN12 from maintenance. NN12 is the normal in-service inverter for the group 2 120-VAC instrument bus (NN02). The actuation occurred while swapping from the swing inverter (NN18) to the normal in-service inverter (NN12).
"All safety systems responded as expected. At 2334, the turbine driven auxiliary feedwater pump was secured.
"The plant is being maintained in a stable condition, in mode 1.
"The NRC Resident Inspector was notified"
The licensee is investigating the cause of the automatic start.
* * * RETRACTION ON 4/25/2024 AT 1432 EDT FROM GREG CIZIN TO ERNEST WEST * * *
"Event Notification (EN) 57043, made on 03/21/2024 pursuant to 10 CFR 50.72(b)(3)(iv)(A), is being retracted based upon further investigation into the cause of the turbine driven auxiliary feedwater pump (TDAFP) actuation. The TDAFP received an invalid manual initiation signal caused by a voltage transient that was generated on the NK02 125-VDC bus upon closure of downstream breaker NK0211 (while restoring inverter NN12 from maintenance). This actuation signal was due to degradation of a 48-VDC power supply (PS1) within engineered safety features actuation system (ESFAS) logic cabinet SA036C. This degradation likely prevented the power supply from sufficiently filtering the transient that occurred on the 125-VDC bus associated with the NN12 inverter."
Notified R4DO (Warnick)
EN Revision Text: AUTOMATIC TURBINE DRIVEN AUXILIARY FEEDWATER PUMP ACTUATION
The following information was provided by the licensee via email:
"At 2056 on 3/21/24, Callaway Plant was in Mode 1 at approximately 100 percent power when an automatic start of the turbine driven auxiliary feedwater pump occurred. The event occurred while restoring inverter NN12 from maintenance. NN12 is the normal in-service inverter for the group 2 120-VAC instrument bus (NN02). The actuation occurred while swapping from the swing inverter (NN18) to the normal in-service inverter (NN12).
"All safety systems responded as expected. At 2334, the turbine driven auxiliary feedwater pump was secured.
"The plant is being maintained in a stable condition, in mode 1.
"The NRC Resident Inspector was notified"
The licensee is investigating the cause of the automatic start.
* * * RETRACTION ON 4/25/2024 AT 1432 EDT FROM GREG CIZIN TO ERNEST WEST * * *
"Event Notification (EN) 57043, made on 03/21/2024 pursuant to 10 CFR 50.72(b)(3)(iv)(A), is being retracted based upon further investigation into the cause of the turbine driven auxiliary feedwater pump (TDAFP) actuation. The TDAFP received an invalid manual initiation signal caused by a voltage transient that was generated on the NK02 125-VDC bus upon closure of downstream breaker NK0211 (while restoring inverter NN12 from maintenance). This actuation signal was due to degradation of a 48-VDC power supply (PS1) within engineered safety features actuation system (ESFAS) logic cabinet SA036C. This degradation likely prevented the power supply from sufficiently filtering the transient that occurred on the 125-VDC bus associated with the NN12 inverter."
Notified R4DO (Warnick)