Event Notification Report for May 17, 2023
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
05/16/2023 - 05/17/2023
Power Reactor
Event Number: 56522
Facility: Diablo Canyon
Region: 4 State: CA
Unit: [1] [] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: Don Townsend
HQ OPS Officer: Karen Cotton-Gross
Region: 4 State: CA
Unit: [1] [] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: Don Townsend
HQ OPS Officer: Karen Cotton-Gross
Notification Date: 05/17/2023
Notification Time: 18:21 [ET]
Event Date: 05/17/2023
Event Time: 06:49 [PDT]
Last Update Date: 05/17/2023
Notification Time: 18:21 [ET]
Event Date: 05/17/2023
Event Time: 06:49 [PDT]
Last Update Date: 05/17/2023
Emergency Class: Non Emergency
10 CFR Section:
26.719 - Fitness For Duty
10 CFR Section:
26.719 - Fitness For Duty
Person (Organization):
Azua, Ray (R4DO)
FFD Group, (EMAIL)
Azua, Ray (R4DO)
FFD Group, (EMAIL)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | Y | 100 | Power Operation | 100 | Power Operation |
FITNESS-FOR-DUTY VIOLATION
The following information was provided by the licensee via email:
On May 17, 2023, at 0649 PDT, it was determined that a prohibited item had been found inside the protected area.
The NRC Resident Inspector has been notified.
The following information was provided by the licensee via email:
On May 17, 2023, at 0649 PDT, it was determined that a prohibited item had been found inside the protected area.
The NRC Resident Inspector has been notified.
Part 21
Event Number: 56603
Rep Org: Engine Systems, Inc.
Licensee: Engine Systems, Inc.
Region: 1
City: Rocky Mount State: NC
County:
License #:
Agreement: Y
Docket:
NRC Notified By: Dan Roberts
HQ OPS Officer: Eric Simpson
Licensee: Engine Systems, Inc.
Region: 1
City: Rocky Mount State: NC
County:
License #:
Agreement: Y
Docket:
NRC Notified By: Dan Roberts
HQ OPS Officer: Eric Simpson
Notification Date: 06/30/2023
Notification Time: 17:09 [ET]
Event Date: 05/17/2023
Event Time: 00:00 [EDT]
Last Update Date: 06/30/2023
Notification Time: 17:09 [ET]
Event Date: 05/17/2023
Event Time: 00:00 [EDT]
Last Update Date: 06/30/2023
Emergency Class: Non Emergency
10 CFR Section:
21.21(d)(3)(i) - Defects And Noncompliance
10 CFR Section:
21.21(d)(3)(i) - Defects And Noncompliance
Person (Organization):
Lally, Christopher (R1DO)
Part 21/50.55 Reactors, - (EMAIL)
Lally, Christopher (R1DO)
Part 21/50.55 Reactors, - (EMAIL)
PART 21 - EMERGENCY DIESEL GENERATOR - INCORRECT BUS BAR INSTALLATION
The following is a summary of the information provided by Engine Systems, Inc. (ESI) via fax:
Copper bus bars are used at rectifier diode pigtail connections CR1, CR2, CR3, CR4, and CR7 to provide a common connection point for associated wiring to minimize the number of conductors on a single fastener. It is intended for the conductors to clamp directly to the bus bar, thereby maintaining a low resistance conduction path between components. ESI has determined the bus bars were installed incorrectly whereby the conductors are not clamped in direct contact, resulting in current now passing through the stainless steel fasteners. This configuration is undesired and will result in unnecessary heat generation which may lead to failure of the connection and therefore failure of the automatic voltage regulator (AVR) assembly. The AVR is relied upon to automatically regulate emergency diesel generator (EDG) terminal voltage. Failure of the AVR would impact the ability of the EDG to perform its safety-related function and therefore may impact the nuclear plant's ability to manage safety-related loads during an emergency event.
This Part 21 applies to the bus bar installation for part numbers 72-12300-100-ESI, 72-14200-100-ESI, and 72-14000-100-6020. These part numbers impact Constellation Energy - Nine Mile Point, Avaltec/CFE - Laguna Verde (Div III), and Avaltec/CFE - Laguna Verde (Div II), respectively.
Corrective Actions:
Voltage regulator installed: Bus bar installation should be corrected immediately by restacking the components to ensure direct contact with all conductors.
Voltage regulators in inventory (not installed): The bus bar installation should be corrected prior to installation. If desired, the customer may perform on site or the voltage regulator chassis may be returned to ESI for rework.
The following is a summary of the information provided by Engine Systems, Inc. (ESI) via fax:
Copper bus bars are used at rectifier diode pigtail connections CR1, CR2, CR3, CR4, and CR7 to provide a common connection point for associated wiring to minimize the number of conductors on a single fastener. It is intended for the conductors to clamp directly to the bus bar, thereby maintaining a low resistance conduction path between components. ESI has determined the bus bars were installed incorrectly whereby the conductors are not clamped in direct contact, resulting in current now passing through the stainless steel fasteners. This configuration is undesired and will result in unnecessary heat generation which may lead to failure of the connection and therefore failure of the automatic voltage regulator (AVR) assembly. The AVR is relied upon to automatically regulate emergency diesel generator (EDG) terminal voltage. Failure of the AVR would impact the ability of the EDG to perform its safety-related function and therefore may impact the nuclear plant's ability to manage safety-related loads during an emergency event.
This Part 21 applies to the bus bar installation for part numbers 72-12300-100-ESI, 72-14200-100-ESI, and 72-14000-100-6020. These part numbers impact Constellation Energy - Nine Mile Point, Avaltec/CFE - Laguna Verde (Div III), and Avaltec/CFE - Laguna Verde (Div II), respectively.
Corrective Actions:
Voltage regulator installed: Bus bar installation should be corrected immediately by restacking the components to ensure direct contact with all conductors.
Voltage regulators in inventory (not installed): The bus bar installation should be corrected prior to installation. If desired, the customer may perform on site or the voltage regulator chassis may be returned to ESI for rework.
Power Reactor
Event Number: 56625
Facility: Columbia Generating Station
Region: 4 State: WA
Unit: [2] [] []
RX Type: [2] GE-5
NRC Notified By: Dan Sharpe
HQ OPS Officer: Adam Koziol
Region: 4 State: WA
Unit: [2] [] []
RX Type: [2] GE-5
NRC Notified By: Dan Sharpe
HQ OPS Officer: Adam Koziol
Notification Date: 07/17/2023
Notification Time: 14:13 [ET]
Event Date: 05/17/2023
Event Time: 03:39 [PDT]
Last Update Date: 07/17/2023
Notification Time: 14:13 [ET]
Event Date: 05/17/2023
Event Time: 03:39 [PDT]
Last Update Date: 07/17/2023
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):
Roldan-Otero, Lizette (R4DO)
Roldan-Otero, Lizette (R4DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | N | N | 0 | Refueling | 100 | Power Operation |
60-DAY OPTIONAL TELEPHONIC NOTIFICATION FOR AN INVALID ACTUATION OF AN EMERGENCY AC ELECTRICAL POWER SYSTEM
The following information was provided by the licensee email:
"At 0339 CDT on May 17, 2023, diesel generator 3 (DG3) had an auto-start during a surveillance test of excess flow check valves in containment atmosphere instrument sensing lines. During the surveillance, workers failed to recognize residual pressure in the system from the test. Per procedure, MS-PS-47C (main steam pressure switch) was placed back in service, resulting in initiation logic for both the high pressure core spray (HPCS) system and DG3 auto-start. Because the HPCS system was tagged out of service for maintenance it did not actuate.
"The auto-start of DG3 was an expected response to the high drywell pressure indication. The signals cleared, and DG3 was shutdown per procedure.
"As indicated in 10 CFR 50.73(a)(1), in the case of an invalid actuation reported under 10 CFR 50.73(a)(2)(iv)(A), the licensee may, at its option, provide a telephonic notification to the NRC Operations Center within 60 days of discovery of the event instead of submitting a written licensee event report. This 60-day telephone notification is being made in accordance with 10 CFR 50.73(a)(1) for invalid actuations reported under 10 CFR 50.73 (a)(2)(iv)(A).
"This actuation was invalid since it was caused by programmatic issues in quality of procedural guidance and not the result of actual plant conditions warranting auto-start of DG3. The actuations were not initiated in response to actual plant conditions, this was not an intentional manual initiation, and there were no parameters satisfying the requirements for initiation. Therefore, this event has been determined to be an invalid actuation.
"Diesel generator 3 system responded as designed to the actuation signal. The HPCS system did not actuate since it was tagged out of service. There was no impact on the health and safety of the public or plant personnel.
"The following information is provided as specified in NUREG-1022:
(a) The diesel generator 3 was actuated.
(b) The actuation of DG3 was complete.
(c) The DG3 train was started and functioned successfully.
"The NRC Resident Inspector has been notified."
The following information was provided by the licensee email:
"At 0339 CDT on May 17, 2023, diesel generator 3 (DG3) had an auto-start during a surveillance test of excess flow check valves in containment atmosphere instrument sensing lines. During the surveillance, workers failed to recognize residual pressure in the system from the test. Per procedure, MS-PS-47C (main steam pressure switch) was placed back in service, resulting in initiation logic for both the high pressure core spray (HPCS) system and DG3 auto-start. Because the HPCS system was tagged out of service for maintenance it did not actuate.
"The auto-start of DG3 was an expected response to the high drywell pressure indication. The signals cleared, and DG3 was shutdown per procedure.
"As indicated in 10 CFR 50.73(a)(1), in the case of an invalid actuation reported under 10 CFR 50.73(a)(2)(iv)(A), the licensee may, at its option, provide a telephonic notification to the NRC Operations Center within 60 days of discovery of the event instead of submitting a written licensee event report. This 60-day telephone notification is being made in accordance with 10 CFR 50.73(a)(1) for invalid actuations reported under 10 CFR 50.73 (a)(2)(iv)(A).
"This actuation was invalid since it was caused by programmatic issues in quality of procedural guidance and not the result of actual plant conditions warranting auto-start of DG3. The actuations were not initiated in response to actual plant conditions, this was not an intentional manual initiation, and there were no parameters satisfying the requirements for initiation. Therefore, this event has been determined to be an invalid actuation.
"Diesel generator 3 system responded as designed to the actuation signal. The HPCS system did not actuate since it was tagged out of service. There was no impact on the health and safety of the public or plant personnel.
"The following information is provided as specified in NUREG-1022:
(a) The diesel generator 3 was actuated.
(b) The actuation of DG3 was complete.
(c) The DG3 train was started and functioned successfully.
"The NRC Resident Inspector has been notified."