Event Notification Report for May 21, 2025
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
05/20/2025 - 05/21/2025
Part 21
Event Number: 57827
Rep Org: Curtiss Wright Flow Control Co.
Licensee:
Region: 3
City: Cincinnati State: OH
County:
License #:
Agreement: Y
Docket:
NRC Notified By: Margie Hover
HQ OPS Officer: Kerby Scales
Licensee:
Region: 3
City: Cincinnati State: OH
County:
License #:
Agreement: Y
Docket:
NRC Notified By: Margie Hover
HQ OPS Officer: Kerby Scales
Notification Date: 07/25/2025
Notification Time: 09:47 [ET]
Event Date: 05/21/2025
Event Time: 00:00 [EDT]
Last Update Date: 11/20/2025
Notification Time: 09:47 [ET]
Event Date: 05/21/2025
Event Time: 00:00 [EDT]
Last Update Date: 11/20/2025
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):
Zurawski, Paul (R3DO)
Part 21/50.55 Reactors, - (EMAIL)
Zurawski, Paul (R3DO)
Part 21/50.55 Reactors, - (EMAIL)
EN Revision Imported Date: 11/21/2025
EN Revision Text: PART 21 INTERIM REPORT OF DEVIATION
The following is a synopsis of information provided by Curtiss-Wright (CW) via email:
On 5/21/2025, Xcel Energy notified Curtiss-Wright about the failure of two NAMCO limit switches provided under CW project CJ21087 (tag number CJ2108701, serial numbers 01 and 04). The limit switches were dedicated by CW and shipped on 2/28/2025 to Xcel Energy. The switches failed a bench test performed by Xcel Energy, which aimed to verify that the contacts properly revert to their original state during spring return. Xcel Energy found that the contacts reverted to their original state prior to the audible click/snap, which is supposed to indicate contact changeover.
The two units were returned to Curtiss-Wright on 5/29/2025. The test result was fully duplicated on one of the switches. For the other switch (serial number 04), the switch contacts intermittently failed to return to the original state at all, requiring manual assistance to do so.
On 6/26/2025, CW sent the parts to NAMCO for repair. CW retested the parts after the repair. Part 04 still had the same issue with failing to reset as noted earlier. That limit switch was returned to NAMCO for a full evaluation.
CW anticipates an update to this notification with final results on 9/23/2025.
Potentially affected U.S. nuclear power plants: unknown at the time of the notification.
Contact Information:
Mark Papke
Quality Assurance Manager
Curtiss-Wright
4600 East Tech Drive
Cincinnati, OH 45245
mpapke@curtisswright.com
* * * UPDATE ON 9/23/25 AT 0850 EDT FROM MARGIE HOVER TO KAREN COTTON * * *
The following information was provided by Curtiss-Wright (CW) via email:
On 6/26/2025 CW sent the relays to NAMCO for repair and the parts were returned to CW on June 26. CW retested the limit switches and one failed for the same issue as noted earlier, the failed limit switch was returned to NAMCO for a full evaluation.
The failure is still under investigation and CW has been in communication with NAMCO, the manufacturer.
Once the evaluation is complete this report will be updated. CW anticipates an update to this notification with final results on 11/24/2025.
Notified R3DO (Szwarc) and the Part 21/50.55 Reactors group
* * * UPDATE ON 11/21/25 AT 1635 EDT FROM MARGIE HOVER TO JORDAN WINGATE * * *
The following information was provided by Curtiss-Wright (CW) via email:
The NAMCO evaluation/report issued to CW on September 4, 2025, concluded that the failure was caused by improper sizing of the hub on the top of the shuttle/slide assembly. The hub was too small which prevented proper fit with the latch and, therefore, the switch could not open or close as intended.
NAMCO confirmed that this failure was only reported on PN: EA700-80926, Date Code: 0425 and also confirmed that the design of PN: EA700-80926 nor supplier of the shuttle/slide assembly has not changed in many years. NAMCO has changed their supplier for the shuttle/slide assembly since the manufacture of PN: EA700-80926, Date Code: 0425. It should also be noted that NAMCO now performs the slow latch test as stated above on all limit switches, not just the E700 series.
To address this issue, CW will be revising all affected NAMCO limit switches' dedication plans to incorporate the slow latch test. CW recommends that end users should perform slow latch testing as a part of their bench or field test procedures upon receiving any Namco limit switches. These actions should preclude a possible recurrence of this failure mechanism.
Please note that CW has not supplied P/N: EA700-80926 of the impacted date code 0425 to any other end users.
Notified R3DO (Orlikowski) and the Part 21/50.55 Reactors group
EN Revision Text: PART 21 INTERIM REPORT OF DEVIATION
The following is a synopsis of information provided by Curtiss-Wright (CW) via email:
On 5/21/2025, Xcel Energy notified Curtiss-Wright about the failure of two NAMCO limit switches provided under CW project CJ21087 (tag number CJ2108701, serial numbers 01 and 04). The limit switches were dedicated by CW and shipped on 2/28/2025 to Xcel Energy. The switches failed a bench test performed by Xcel Energy, which aimed to verify that the contacts properly revert to their original state during spring return. Xcel Energy found that the contacts reverted to their original state prior to the audible click/snap, which is supposed to indicate contact changeover.
The two units were returned to Curtiss-Wright on 5/29/2025. The test result was fully duplicated on one of the switches. For the other switch (serial number 04), the switch contacts intermittently failed to return to the original state at all, requiring manual assistance to do so.
On 6/26/2025, CW sent the parts to NAMCO for repair. CW retested the parts after the repair. Part 04 still had the same issue with failing to reset as noted earlier. That limit switch was returned to NAMCO for a full evaluation.
CW anticipates an update to this notification with final results on 9/23/2025.
Potentially affected U.S. nuclear power plants: unknown at the time of the notification.
Contact Information:
Mark Papke
Quality Assurance Manager
Curtiss-Wright
4600 East Tech Drive
Cincinnati, OH 45245
mpapke@curtisswright.com
* * * UPDATE ON 9/23/25 AT 0850 EDT FROM MARGIE HOVER TO KAREN COTTON * * *
The following information was provided by Curtiss-Wright (CW) via email:
On 6/26/2025 CW sent the relays to NAMCO for repair and the parts were returned to CW on June 26. CW retested the limit switches and one failed for the same issue as noted earlier, the failed limit switch was returned to NAMCO for a full evaluation.
The failure is still under investigation and CW has been in communication with NAMCO, the manufacturer.
Once the evaluation is complete this report will be updated. CW anticipates an update to this notification with final results on 11/24/2025.
Notified R3DO (Szwarc) and the Part 21/50.55 Reactors group
* * * UPDATE ON 11/21/25 AT 1635 EDT FROM MARGIE HOVER TO JORDAN WINGATE * * *
The following information was provided by Curtiss-Wright (CW) via email:
The NAMCO evaluation/report issued to CW on September 4, 2025, concluded that the failure was caused by improper sizing of the hub on the top of the shuttle/slide assembly. The hub was too small which prevented proper fit with the latch and, therefore, the switch could not open or close as intended.
NAMCO confirmed that this failure was only reported on PN: EA700-80926, Date Code: 0425 and also confirmed that the design of PN: EA700-80926 nor supplier of the shuttle/slide assembly has not changed in many years. NAMCO has changed their supplier for the shuttle/slide assembly since the manufacture of PN: EA700-80926, Date Code: 0425. It should also be noted that NAMCO now performs the slow latch test as stated above on all limit switches, not just the E700 series.
To address this issue, CW will be revising all affected NAMCO limit switches' dedication plans to incorporate the slow latch test. CW recommends that end users should perform slow latch testing as a part of their bench or field test procedures upon receiving any Namco limit switches. These actions should preclude a possible recurrence of this failure mechanism.
Please note that CW has not supplied P/N: EA700-80926 of the impacted date code 0425 to any other end users.
Notified R3DO (Orlikowski) and the Part 21/50.55 Reactors group
Part 21
Event Number: 57729
Rep Org: Framatome ANP
Licensee: Framatome Inc
Region: 1
City: Lynchburg State: VA
County:
License #:
Agreement: N
Docket:
NRC Notified By: Gayle Elliott
HQ OPS Officer: Jordan Wingate
Licensee: Framatome Inc
Region: 1
City: Lynchburg State: VA
County:
License #:
Agreement: N
Docket:
NRC Notified By: Gayle Elliott
HQ OPS Officer: Jordan Wingate
Notification Date: 05/22/2025
Notification Time: 09:15 [ET]
Event Date: 05/21/2025
Event Time: 00:00 [EDT]
Last Update Date: 05/22/2025
Notification Time: 09:15 [ET]
Event Date: 05/21/2025
Event Time: 00:00 [EDT]
Last Update Date: 05/22/2025
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):
Josey, Jeffrey (R4DO)
Josey, Jeffrey (R4DO)
EN Revision Imported Date: 5/27/2025
EN Revision Text: PART 21 REPORT- CIRCUIT BREAKER DEFECT
The following information is a summary provided by the licensee via phone and email:
Twenty-one (21) breakers were installed at Arkansas Nuclear One (ANO) by Framatome Inc during a recent refurbishment. During the refurbishment, shorter bell cranks were installed to mitigate an identified interference. These shorter bell cranks result in a higher force being needed to close the breaker which could result in failure of the pushrods. In the event of a pushrod failure, the breaker may not trip when required, resulting in a substantial safety hazard.
Framatome has provided written correspondence to ANO to advise on this issue.
Model: 5-3AF-GEU-350-1200 Breaker
Affected plants: Arkansas Nuclear One
Gayle Elliott
Director, Licensing Regulatory Affairs
Framatome Inc.
gayle.elliott@framatome.com
EN Revision Text: PART 21 REPORT- CIRCUIT BREAKER DEFECT
The following information is a summary provided by the licensee via phone and email:
Twenty-one (21) breakers were installed at Arkansas Nuclear One (ANO) by Framatome Inc during a recent refurbishment. During the refurbishment, shorter bell cranks were installed to mitigate an identified interference. These shorter bell cranks result in a higher force being needed to close the breaker which could result in failure of the pushrods. In the event of a pushrod failure, the breaker may not trip when required, resulting in a substantial safety hazard.
Framatome has provided written correspondence to ANO to advise on this issue.
Model: 5-3AF-GEU-350-1200 Breaker
Affected plants: Arkansas Nuclear One
Gayle Elliott
Director, Licensing Regulatory Affairs
Framatome Inc.
gayle.elliott@framatome.com
Power Reactor
Event Number: 57725
Facility: River Bend
Region: 4 State: LA
Unit: [1] [] []
RX Type: [1] GE-6
NRC Notified By: Jason Fortenberry
HQ OPS Officer: Jordan Wingate
Region: 4 State: LA
Unit: [1] [] []
RX Type: [1] GE-6
NRC Notified By: Jason Fortenberry
HQ OPS Officer: Jordan Wingate
Notification Date: 05/21/2025
Notification Time: 10:50 [ET]
Event Date: 05/21/2025
Event Time: 06:26 [CDT]
Last Update Date: 05/21/2025
Notification Time: 10:50 [ET]
Event Date: 05/21/2025
Event Time: 06:26 [CDT]
Last Update Date: 05/21/2025
Emergency Class: Non Emergency
10 CFR Section:
50.72(b)(2)(i) - Plant S/D Reqd By TS
10 CFR Section:
50.72(b)(2)(i) - Plant S/D Reqd By TS
Person (Organization):
Josey, Jeffrey (R4DO)
Grant, Jeffery (IR MOC)
Felts, Russell (NRR EO)
Josey, Jeffrey (R4DO)
Grant, Jeffery (IR MOC)
Felts, Russell (NRR EO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | Y | 100 | Power Operation | 50 | Power Operation |
TECHNICAL SPECIFICATION REQUIRED SHUTDOWN
The following information was provided by the licensee via phone and email:
"On May 21, 2025, at 0656 CDT, River Bend Station (RBS) was operating at 100 percent reactor power when a plant shut down was initiated due to technical specification (TS) requirements. At 0324 on May 21, 2025, unidentified drywell leakage exceeded a 2 gallon per minute change over a 24-hour period. TS limiting condition of operation 3.4.5 condition 'C' was entered with a required action to verify the source of the unidentified leakage increase is not from service sensitive type 304, type 316 austenitic stainless steel, or other inter-granular stress corrosion cracking susceptible material within 4 hours. This required action could not be completed within the completion time.
"This event is being reported under 10 CFR 50.72(b)(2)(i) as an event or condition that results in a TS required plant shut down.
"The NRC Resident has been notified."
The following information was provided by the licensee via phone and email:
"On May 21, 2025, at 0656 CDT, River Bend Station (RBS) was operating at 100 percent reactor power when a plant shut down was initiated due to technical specification (TS) requirements. At 0324 on May 21, 2025, unidentified drywell leakage exceeded a 2 gallon per minute change over a 24-hour period. TS limiting condition of operation 3.4.5 condition 'C' was entered with a required action to verify the source of the unidentified leakage increase is not from service sensitive type 304, type 316 austenitic stainless steel, or other inter-granular stress corrosion cracking susceptible material within 4 hours. This required action could not be completed within the completion time.
"This event is being reported under 10 CFR 50.72(b)(2)(i) as an event or condition that results in a TS required plant shut down.
"The NRC Resident has been notified."
Agreement State
Event Number: 57727
Rep Org: Florida Bureau of Radiation Control
Licensee: Gables Radiology Associates, PA
Region: 1
City: Miami State: FL
County:
License #: 4649-1
Agreement: Y
Docket:
NRC Notified By: Mark Seidensticker
HQ OPS Officer: Sam Colvard
Licensee: Gables Radiology Associates, PA
Region: 1
City: Miami State: FL
County:
License #: 4649-1
Agreement: Y
Docket:
NRC Notified By: Mark Seidensticker
HQ OPS Officer: Sam Colvard
Notification Date: 05/21/2025
Notification Time: 14:12 [ET]
Event Date: 05/21/2025
Event Time: 00:00 [EDT]
Last Update Date: 05/21/2025
Notification Time: 14:12 [ET]
Event Date: 05/21/2025
Event Time: 00:00 [EDT]
Last Update Date: 05/21/2025
Emergency Class: Non Emergency
10 CFR Section:
Agreement State
10 CFR Section:
Agreement State
Person (Organization):
Lilliendahl, Jon (R1DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
ILTAB, (EMAIL) (EMAIL)
Lilliendahl, Jon (R1DO)
NMSS_EVENTS_NOTIFICATION (EMAIL)
ILTAB, (EMAIL) (EMAIL)
AGREEMENT STATE REPORT - LOST SOURCE
The following information was provided by the Florida Bureau of Radiation Control (BRC) via email:
"The radiation safety officer (RSO) called the BRC to report a lost Ge-68 pin source from their PET scanner. It was discovered missing about a week ago. The RSO said the source had a reference date of April 1, 2021, with an initial activity of 1.49 mCi. Apparently, the previous consultant tried to send it back to Eckert and Zeigler in 2021, but it was returned twice from the common carrier due to not being packaged properly. Eckert and Zeigler apparently never received the source. The RSO has copies of the paperwork from the common carrier, but the dates do not line up. The BRC Miami inspection office will follow up with an investigation."
Florida Incident Number: FL25-049.
The following information was provided by the Florida Bureau of Radiation Control (BRC) via email:
"The radiation safety officer (RSO) called the BRC to report a lost Ge-68 pin source from their PET scanner. It was discovered missing about a week ago. The RSO said the source had a reference date of April 1, 2021, with an initial activity of 1.49 mCi. Apparently, the previous consultant tried to send it back to Eckert and Zeigler in 2021, but it was returned twice from the common carrier due to not being packaged properly. Eckert and Zeigler apparently never received the source. The RSO has copies of the paperwork from the common carrier, but the dates do not line up. The BRC Miami inspection office will follow up with an investigation."
Florida Incident Number: FL25-049.