IR 05000250/2025003
| ML25342A106 | |
| Person / Time | |
|---|---|
| Site: | Turkey Point  |
| Issue date: | 12/09/2025 |
| From: | Shawn Smith NRC/RGN-II/DORS/PB6 |
| To: | Coffey R Florida Power & Light Co |
| References | |
| IR 2025003 | |
| Download: ML25342A106 (0) | |
Text
SUBJECT:
TURKEY POINT NUCLEAR GENERATING, UNITS 3 AND 4 - INTEGRATED INSPECTION REPORT 05000250/2025003 AND 05000251/2025003
Dear Robert Coffey:
On September 30, 2025, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Turkey Point Nuclear Generating, Units 3 and 4. On October 9, 2025, the NRC inspectors discussed the results of this inspection with Mr. Michael Durbin, Site Vice President and other members of your staff. The results of this inspection are documented in the enclosed report.
Due to the temporary cessation of government operations, which commenced on October 1, 2025, the NRC began operating under its Office of Management and Budget-approved plan for operations during a lapse in appropriations. Consistent with that plan, the NRC operated at reduced staffing levels throughout the duration of the shutdown. However, the NRC continued to perform critical health and safety functions and make progress on other high-priority activities associated with the ADVANCE Act and Executive Order 14300. On November 13, 2025, following the passage of a continuing resolution, the NRC resumed normal operations.
However, due to the 43-day lapse in normal operations, the Office of Nuclear Reactor Regulation granted the Regional Offices an extension on the issuance of the calendar year 2025 inspection reports that should have been issued by November 13, 2025, to December 31, 2025. The NRC resumed the routine cycle of issuing inspection reports on November 13, 2025.
Two findings of very low safety significance (Green) are documented in this report. Two of these findings involved violations of NRC requirements. Two Severity Level IV violations without an associated finding are documented in this report. We are treating these violations as non-cited violations (NCVs) consistent with Section 2.3.2 of the Enforcement Policy.
If you contest the violations or the significance or severity of the violations documented in this inspection report, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the U.S. Nuclear Regulatory Commission, ATTN:
Document Control Desk, Washington, DC 20555-0001; with copies to the Regional Administrator, Region II; the Director, Office of Enforcement; and the NRC Resident Inspector at Turkey Point Nuclear Generating, Units 3 and 4.
December 9, 2025 If you disagree with a cross-cutting aspect assignment in this report, you should provide a response within 30 days of the date of this inspection report, with the basis for your disagreement, to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, DC 20555-0001; with copies to the Regional Administrator, Region II; and the NRC Resident Inspector at Turkey Point Nuclear Generating, Units 3 and 4.
This letter, its enclosure, and your response (if any) will be made available for public inspection and copying at http://www.nrc.gov/reading-rm/adams.html and at the NRC Public Document Room in accordance with Title 10 of the Code of Federal Regulations 2.390, Public Inspections, Exemptions, Requests for Withholding.
Sincerely, Steven P. Smith, Chief Projects Branch 6 Division of Operating Reactor Safety Docket Nos. 05000250 and 05000251 License Nos. DPR-31 and DPR-41
Enclosure:
As stated
Inspection Report
Docket Numbers:
05000250 and 05000251
License Numbers:
Report Numbers:
05000250/2025003 and 05000251/2025003
Enterprise Identifier:
I-2025-003-0016
Licensee:
Florida Power & Light Company
Facility:
Turkey Point Nuclear Generating, Units 3 and 4
Location:
Homestead, FL 33035
Inspection Dates:
July 01, 2025 to September 30, 2025
Inspectors:
A. Donley, Senior Resident Inspector
A. Knotts, Resident Inspector
Approved By:
Steven P. Smith, Chief
Projects Branch 6
Division of Operating Reactor Safety
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at Turkey Point Nuclear Generating, Units and 4, in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRCs program for overseeing the safe operation of commercial nuclear power reactors.
Refer to https://www.nrc.gov/reactors/operating/oversight.html for more information.
List of Findings and Violations
Non-Functional Fire Door Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000250/2025003-01 Open/Closed
[P.1] -
Identification 71111.05 The inspectors identified a Green finding and associated non-cited violation (NCV) of Turkey Point Unit 3 subsequent renewed facility operating license, DPR-31, condition 3.D, Fire Protection, for the licensee's failure to implement and maintain in effect all provisions of the approved fire protection program that comply with 10 CFR 50.48(a) and 10 CFR 50.48(c).
Specifically, the licensee failed to maintain the Unit 3 west electrical penetration room fire door (019-1) design requirements in accordance with licensee procedure, 3-SMM-016.6, Fire Door Inspection Unit 3/Common, which specifies the requirements for a functional fire barrier per 0-ADM-016, Fire Protection Program.
Failure to Remove Foreign Material from Protective Relay Results in 4A 4kV Bus Lockout and Subsequent Unit 4 Reactor Trip Cornerstone Significance Cross-Cutting Aspect Report Section Initiating Events Green NCV 05000251/2025003-02 Open/Closed
[H.13] -
Consistent Process 71111.12 A self-revealed very low safety significance (Green) finding and associated NCV of Turkey Point Unit 4 Improved Technical Specification (ITS) section 5.4, "Procedures," was identified for the licensees failure to perform an adequate foreign material exclusion (FME) closeout inspection prior to a maintenance run of the Unit 4A emergency diesel generator (EDG).
Specifically, Turkey Point (PTN) failed to complete work order (WO) 409550189 instruction step 4.2 to satisfactorily perform a FME closeout inspection for the 4A EDG relay and metering panel as indicated by tape holding the 160-voltage differential relay in an actuated position, which resulted in the 4A 4kV bus being locked out and an automatic reactor trip of Unit 4 coincident with an automatic safety injection.
Condition Prohibited by TS due to Inoperable Power Range Nuclear Instrument Cornerstone Severity Cross-Cutting Aspect Report Section Not Applicable Severity Level IV NCV 05000250/2025003-03 Open/Closed Not Applicable 71111.12 The inspectors identified a Severity Level (SL) IV NCV of Turkey Point Unit 3 Improved Technical Specification 3.3.1, Reactor Trip System Instrumentation, for the failure to complete required actions for an inoperable power range nuclear instrument (NI). Specifically, the licensee entered Mode 2 and started up the reactor following a refueling outage with one power range neutron flux low channel inoperable from November 14-19, 2024, and the required channel was not placed in trip or the required mode change made. Consequently, the licensee entered a condition prohibited by technical specifications.
4C Component Cooling Water Auto-Start Signal Inoperable Cornerstone Severity Cross-Cutting Aspect Report Section Not Applicable Severity Level IV NCV 05000251/2025003-04 Open/Closed Not Applicable 71111.15 A self-revealed SL IV NCV of ITS 3.3.2, Engineered Safety Features Actuation System (ESFAS) Instrumentation, limiting condition for operations (LCO) was identified when the licensee failed to ensure both trains of ESFAS auto-start feature for the 4C component cooling water (CCW) pump were operable.
Additional Tracking Items
Type Issue Number Title Report Section Status LER 05000250/2024-003-01 LER 2024-003-01 for Turkey Point, Unit 3, Condition Prohibited by Technical Specifications 71111.12 Closed LER 05000250/2024-003-00 LER 2024-003-00 for Turkey Point Unit 3, Condition Prohibited by Technical Specifications 71111.12 Closed LER 05000251/2025-004-00 LER 2025-004-00 for Turkey Point, Unit 4, Unplanned Reactor Scram 71111.12 Closed LER 05000251/2025-003-00 LER 2025-03-00 for Turkey Point, Unit 4, 4B Component Cooling Pump and its Associated Breaker Inoperable 71111.15 Closed LER 05000251/2025-002-01 LER 2025-002-01 for Turkey Point Unit 4, Emergency Diesel Generator Actuation 71111.18 Closed LER 05000251/2025-002-00 LER 2025-002-00 for Turkey Point, Unit 4, Emergency Diesel Generator Actuation 71111.18 Closed
PLANT STATUS
Unit 3 began the inspection period at rated thermal power (RTP). On August 9, 2025, the unit experienced a turbine trip and reactor trip due to a loss of power to the turbine control system.
The unit was returned to RTP on August 12, 2025, and remained at or near RTP for the remainder of the inspection period.
Unit 4 operated at or near RTP for the entire inspection period.
INSPECTION SCOPES
Inspections were conducted using the appropriate portions of the inspection procedures (IPs) in effect at the beginning of the inspection unless otherwise noted. Currently approved IPs with their attached revision histories are located on the public website at http://www.nrc.gov/reading-rm/doc-collections/insp-manual/inspection-procedure/index.html. Samples were declared complete when the IP requirements most appropriate to the inspection activity were met consistent with Inspection Manual Chapter (IMC) 2515, Light-Water Reactor Inspection Program - Operations Phase. The inspectors performed activities described in IMC 2515, Appendix D, Plant Status, observed risk significant activities, and completed on site portions of IPs. The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel to assess licensee performance and compliance with Commission rules and regulations, license conditions, site procedures, and standards.
REACTOR SAFETY
71111.04 - Equipment Alignment
Partial Walkdown Sample (IP Section 03.01) (2 Samples)
The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:
- (1) Unit 4 alternate shutdown panel standby alignment on August 4, 2025
- (2) Train 1 auxiliary feed water (AFW) standby alignment after A AFW pump overspeed trip test on August 21, 2025
71111.05 - Fire Protection
Fire Area Walkdown and Inspection Sample (IP Section 03.01) (3 Samples)
The inspectors evaluated the implementation of the fire protection program by conducting a walkdown and performing a review to verify program compliance, equipment functionality, material condition, and operational readiness of the following fire areas:
- (1) Fire zone 19, Unit 3 west electrical penetration room on August 13, 2025
- (2) Fire zones 45, 55, and 58, Unit 3 charging pump room, Unit 4 charging pump room, and auxiliary building hallway on September 5, 2025
- (3) Fire zones 67 and 68, 4A and 4B 4160V switchgear rooms on September 12, 2025
Fire Brigade Drill Performance Sample (IP Section 03.02) (1 Sample)
- (1) The inspectors evaluated the onsite fire brigade training and performance during an actual event when smoke was reported coming from the new electrical equipment room on July 29, 2025
71111.11Q - Licensed Operator Requalification Program and Licensed Operator Performance
Licensed Operator Performance in the Actual Plant/Main Control Room (IP Section 03.01) (1 Sample)
- (1) The inspectors observed and evaluated licensed operator performance in the control room during Unit 3 reactor startup following a turbine trip and subsequent reactor trip on August 11, 2025
Licensed Operator Requalification Training/Examinations (IP Section 03.02) (1 Sample)
- (1) The inspectors observed and evaluated reactor operator performance during an emergency preparedness training exercise to test site readiness for implementation of the common emergency plan on August 5, 2025
71111.12 - Maintenance Effectiveness
Maintenance Effectiveness (IP Section 03.01) (2 Samples)
The inspectors evaluated the effectiveness of maintenance to ensure the following structures, systems, and components (SSCs) remain capable of performing their intended function:
- (1) Maintenance rule evaluation, EVT-059-2024-51158, for N-3-43A, power range channel III, signal cable low resistance and inoperability, on September 30, 2025
- (2) Work order (WO) 41001497, emergency diesel generator (EDG) voltage regulator and governor testing, resulting in a 4A 4kV bus lockout and subsequent reactor trip (action request (AR) 2517978), on June 21, 2025
71111.13 - Maintenance Risk Assessments and Emergent Work Control
Risk Assessment and Management Sample (IP Section 03.01) (2 Samples)
The inspectors evaluated the accuracy and completeness of risk assessments for the following planned and emergent work activities to ensure configuration changes and appropriate work controls were addressed:
- (1) Unit 4 planned high risk during 4A component cooling water (CCW) pump in-service test, while 4B CCW pump was inoperable, on August 21, 2025
- (2) Unit 3 emergent high risk during first time evolution of replacing positioner #1 on the flow controller for the 3A main feedwater regulating valve, on August 28, 2025
71111.15 - Operability Determinations and Functionality Assessments
Operability Determination or Functionality Assessment (IP Section 03.01) (3 Samples)
The inspectors evaluated the licensee's justifications and actions associated with the following operability determinations and functionality assessments:
- (1) AR 2517143, 4C CCW pump auto start feature inoperable
- (2) AR 2522437, PCV-3-605, residual heat removal (RHR) bypass pressure control valve, instrument air leak
- (3) AR 2524098, CV-3-2908 3A emergency containment cooler main control valve low margin for minimum stroke time
71111.18 - Plant Modifications
Temporary Modifications and/or Permanent Modifications (IP Section 03.01 and/or 03.02) (1 Sample)
The inspectors evaluated the following temporary modification:
- (1) Engineering change (EC) 300494, temporary modification to isolate switchyard protective relay trips to Unit 4 startup transformer breaker (4AB05)
71111.24 - Testing and Maintenance of Equipment Important to Risk
The inspectors evaluated the following testing and maintenance activities to verify system operability and/or functionality:
Post-Maintenance Testing (PMT) (IP Section 03.01) (3 Samples)
- (1) WO 40990457, 4A EDG operability test following major maintenance
- (2) WO 41002322, D52, spare vital battery PMT following replacement of battery string after test failure, AR 2520429
- (3) WO 40998820, PMT of the 4A intake cooling water pump (ICW) following emergent replacement of a shorted motor
Inservice Testing (IST) (IP Section 03.01) (1 Sample)
(1)3-OSP-019.1, Intake Cooling Water Inservice Test, on August 14,
OTHER ACTIVITIES - BASELINE
===71151 - Performance Indicator Verification The inspectors verified licensee performance indicators submittals listed below:
MS05: Safety System Functional Failures (SSFFs) Sample (IP Section 02.04)===
- (1) Unit 3 (July 1, 2024, through June 30, 2025)
- (2) Unit 4 (July 1, 2024, through June 30, 2025)
71152S - Semiannual Trend Problem Identification and Resolution Semiannual Trend Review (Section 03.02)
- (1) The inspectors reviewed the licensees corrective action program to identify potential trends in fire door reliability that might be indicative of a more significant safety issue.
No negative trends that could lead to a safety significant issue were identified.
71153 - Follow-up of Events and Notices of Enforcement Discretion Event Follow-up (IP Section 03.01)
- (1) The inspectors evaluated Unit 3 turbine trip and subsequent reactor trip due to turbine control system channel failures and the licensees response on August 9, 2025.
Event Report (IP Section 03.02) (4 Samples)
The inspectors evaluated the following licensee event reports (LERs):
- (1) LER 05000250/2024-003-00 and LER 0500250/2024-003-01, Condition Prohibited by Technical Specifications (Agencywide Documents Access and Management System (ADAMS) Accession No. ML25015A089 and ML25065A080)
The inspectors reviewed both the updated LER submittal and the previous LER submittal. The inspection conclusions associated with this LER (Severity Level (SL)
IV non-cited violation (NCV)) are documented in this report under Inspection Results Section 71111.12. This LER is Closed.
- (2) LER 05000251/2025-002-00 and LER 05000251/2025-002-01, Emergency Diesel Generator Actuation (ADAMS Accession No. ML25129A103 and ML25174A283)
The inspectors determined that the cause of the condition described in the LER and updated LER was not reasonably within the licensee's ability to foresee and correct and therefore was not reasonably preventable. No performance deficiency nor violation of NRC requirements was identified. This LER is Closed.
- (3) LER 05000251/2025-03-00, 4B Component Cooling Pump and its Associated Breaker Inoperable, (ADAMS Accession No. ML25216A111)
The inspection conclusions associated with this LER (SL IV NCV) are documented in this report under Inspection Results Section 71111.15. This LER is Closed.
- (4) LER 05000251/2025-04-00, Unplanned Reactor Scram, (ADAMS Accession No.
The inspection conclusions associated with this LER (Green finding and associated NCV) are documented in this report under Inspection Results Section 71111.12. This LER is Closed.
INSPECTION RESULTS
Non-Functional Fire Door Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000250/2025003-01 Open/Closed
[P.1] -
Identification 71111.05 The inspectors identified a Green finding and associated non-cited violation (NCV) of Turkey Point Unit 3 subsequent renewed facility operating license, DPR-31, condition 3.D, Fire Protection, for the licensee's failure to implement and maintain in effect all provisions of the approved fire protection program that comply with 10 CFR 50.48(a) and 10 CFR 50.48(c).
Specifically, the licensee failed to maintain the Unit 3 west electrical penetration room fire door (019-1) design requirements in accordance with licensee procedure, 3-SMM-016.6, Fire Door Inspection Unit 3/Common, which specifies the requirements for a functional fire barrier per 0-ADM-016, Fire Protection Program.
Description:
While conducting a plant walkdown on August 13, 2025, the inspectors noted degraded concrete around fire door 019-1, Unit 3 west electrical penetration room. The inspector reviewed the licensee's fire door inspection procedure, 3-SMM-016.6, Fire Door Inspection Unit 3/Common, Revision 1, to confirm design requirements and acceptance criteria for the maximum floor gap for fire doors. Step 6.2.5 stated an acceptance criterion of "Bottom of door to floor without sill = 1-inch maximum gap." The inspectors performed measurements of the gap at the bottom of the door and determined it exceeded the 1-inch acceptance criterion. The licensee performed an inspection and confirmed the gap exceeded the 1-inch procedural requirements. Operations declared the door non-functional, opened a fire impairment (FPI), and initiated a fire watch.
The inspectors concluded that the licensee did not maintain the design parameters of the fire door. The design requirements of the fire protection program related to this issue are established to prevent the potential spread of fire between zones. Licensee surveillance procedure, 3-SMM-016.6, specifies the design requirements for functional fire barriers in accordance with 0-ADM-016, Fire Protection Program, Revision 44. Procedure 0-ADM-016 is the implementing procedure for the fire protection program and section 5.6.5 Fire Rated Assemblies, classifies fire door 019-1 as a Group 2 fire barrier, requiring the fire door inspection surveillances to be completed on a 2-year frequency. The last successfully completed 3-SMM-016.6 was on June 20, 2024. The fire door design requirements were not maintained in accordance with required procedures, which impacted the function to prevent the spread of a fire between fire zones.
Corrective Actions: The licensee confirmed the inspectors observations on August 14, 2025, documented the issue in action request (AR) 02521521, initiated FPI 14982, and established a fire watch.
Corrective Action References: AR 02521521
Performance Assessment:
Performance Deficiency: The licensees failure to maintain the design requirements for fire door 019-1, which resulted in a non-functional door, fire impairment, and fire watch, was a performance deficiency within the licensees ability to foresee and prevent.
Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Protection Against External Factors attribute of the Mitigating Systems cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. The functional integrity of the fire barrier penetration ensures that fires will be confined or adequately retarded from spreading to adjacent portions of the facility.
The fire door did not meet all its required parameters for a functional barrier for a design-basis fire. Specifically, the licensee procedural requirements were not met, and the as left condition impacted the ability of the door to perform its function which affected the fire barriers functionality. The inspectors used IMC 0612 Appendix E, Examples of Minor Issues, to inform answers to the more than minor screening questions and found this condition consistent with more than minor Example 2.d in that the licensee requirements were not met and impacted the fire barriers functionality.
Significance: The inspectors assessed the significance of the finding using IMC 0609 Appendix F, Fire Protection and Post - Fire Safe Shutdown SDP. The inspectors assigned this issue to the fire confinement finding category because it related to a fire door. The inspectors determined this issue to have a high degradation rating in accordance with IMC 0609, Appendix F, Attachment 2, Degradation Rating Guidance, because of holes in the door surface with greater than 1 inch opening. The finding was determined to be of very low safety significance (Green) because the degraded fire confinement element will continue to provide adequate fire endurance to prevent fire propagation through the fire confinement element, given the combustible loading and location of equipment important to a safe shutdown in the fire area, in accordance with IMC 0609, Appendix F, Attachment 1, Step 1.4.4: Fire Confinement, Question 1.4.4-A.
Cross-Cutting Aspect: P.1 - Identification: The organization implements a corrective action program with a low threshold for identifying issues. Individuals identify issues completely, accurately, and in a timely manner in accordance with the program. Specifically, the degraded concrete floor around the fire door was not identified, nor was the impact on the fire door functionality identified.
Enforcement:
Violation: Turkey Point Unit 3 subsequent renewed facility operating license, DPR-31, condition 3.D, Fire Protection, states, in part, that the licensee shall implement and maintain in effect, all provisions of the approved fire protection program that comply with 10 CFR 50.48(a) and 10 CFR 50.48(c). Licensee procedure, 0-ADM-016, Fire Protection Program, Revision 44, is one of the fire protection programs implementing documents. 0-ADM-016, section 5.6.5,Fire Rated Assemblies, requires, that all fire rated assemblies (walls, floors, ceilings, fire barrier penetration seals, raceway protection, and other fire barriers) separating fire areas or otherwise protecting specified nuclear safety functions and all sealing devices in fire rated assembly penetrations (fire doors, fire windows, fire dampers, cable, piping, and ventilation duct penetration seals) shall be functional. With one or more of the Group 2 required fire rated assemblies and/or sealing devices non-functional, within eight hours, the licensee is required to establish a fire watch on at least one side of the affected assembly.
Contrary to the above, prior to August 13, 2025, the licensee failed to implement and maintain in effect all provisions of the approved fire protection program as described in 0-ADM-016.
Specifically, the licensee failed to ensure that the Unit 3 west electrical penetration room fire door, 019-1, did not exceed the maximum floor gap requirements due to degraded concrete conditions around and underneath the door.
Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Failure to Remove Foreign Material from Protective Relay Results in 4A 4kV Bus Lockout and Subsequent Unit 4 Reactor Trip Cornerstone Significance Cross-Cutting Aspect Report Section Initiating Events Green NCV 05000251/2025003-02 Open/Closed
[H.13] -
Consistent Process 71111.12 A self-revealed very low safety significance (Green) finding and associated NCV of Turkey Point Unit 4 Improved Technical Specification (ITS) section 5.4, "Procedures," was identified for the licensees failure to perform an adequate foreign material exclusion (FME) closeout inspection prior to a maintenance run of the Unit 4A emergency diesel generator (EDG).
Specifically, Turkey Point (PTN) failed to complete work order (WO) 409550189 instruction step 4.2 to satisfactorily perform a FME closeout inspection for the 4A EDG relay and metering panel as indicated by tape holding the 160-voltage differential relay in an actuated position, which resulted in the 4A 4kV bus being locked out and an automatic reactor trip of Unit 4 coincident with an automatic safety injection.
Description:
Turkey Point (PTN) entered a planned maintenance window for the 4A emergency diesel generator (EDG) on June 11, 2025, at 1700. On June 21, 2025, the licensee began their EDG maintenance run in accordance with 4-OP-023.1, Revision 16 due to the replacement of the electronic governor and digital reference unit (DRU). Prior to the EDG run, PTN maintenance was required to perform relay and metering alarm checks in accordance with 0-PME-005.22, Revision 3. The alarm checks were completed satisfactorily on June 21, 2025.
During the 4A EDG maintenance run at 1438, 30 sec after the EDG was synced to the 4A 4kV bus, the 4A EDG breaker tripped on overcurrent and a lockout of the 4A 4kV bus occurred. This lockout resulted in a loss of power to the 4A reactor coolant pump (RCP) and a subsequent automatic trip of the Unit 4 reactor on low reactor coolant system (RCS) flow.
An automatic safety injection (SI) and phase A containment isolation also occurred due to a 100-psig differential pressure between the 4A steam generator and main steam header. The loss of power to the 4A 4kV bus lockout resulted in two steam generator blowdown sample motor operated valves (MOVs) failing to close. These valves are a part of containment phase A isolation signal. PTN declared an unusual event due to the MOVs failing to close within 15 minutes.
From the licensees investigation, it was noted the 160-voltage differential relay in the 4A EDG control panel had a contact taped closed. This was a condition left over from performance of 0-PME-005.22. Because the relay was taped, the 4A EDG voltage regulator demand was aligned to the 4kV bus vice the output of the 4A EDG, which is not the preferred alignment. It was also noted in the field that the XRCG-C phase fuses were blown. In the event configuration, the fuses were part of the sensing line of the voltage regulator circuit.
During the EDG maintenance run, the licensee determined that the taped relay, coincident with the blown C phase fuses created an overcurrent condition which caused the 4A EDG breaker to trip and lock out the 4A 4kV bus. The tape was removed from the relay, and the fuses were replaced. On June 21, at 2112, the 4A 4kV bus was energized from the U4 startup transformer, and the 4kV bus lockout was reset. The 4A 4kV bus was fully restored and returned to operable on June 21, at 2125. The 4A EDG was not restored to operable until June 25, after the completion of the maintenance window.
0-PME-005.22 was performed under work order (WO) 40950189. Step 4.2 of the WO instructions required implementation of a FME area 2. This is accomplished in accordance with licensee procedure MA-AA-101-1000, Foreign Material Exclusion Procedure, Revision 33. Also, step 6.1 of the WO instructions required that maintenance personnel, Ensure all affected equipment has been restored to the as found configuration unless modified by an approved design change document.
The licensee noted an issue with the 4A EDG voltmeter circuit on June 13, 2025. The 4A 4kV bus voltage was reading zero, yet it was determined that this was only an indication issue and not an actual loss of phase voltage. The issue was documented under AR 2517447 and maintained the discrepancy in their daily plant status report due to reduced equipment reliability. A work request (WR) was generated under WR number 94275326, and it was actioned to be worked on June 20. The licensee understood this was a loss of margin to their post-accident monitoring (PAM) indications, which additional failures could result in a 30-day Technical Specification Action 3.3.3 FU 21. The cause was later found to be due to the blown XRCG-C phase fuses.
Corrective Actions: The licensee reset and cleared the bus lockout, restored the 4A 4kV bus.
The tape was removed from the 160-voltage differential relay and the blown XRCG fuses were replaced. The site successfully completed the 4A EDG maintenance run and restored the 4A EDG to operable. Procedure 0-PME-005.22 was revised to provide clear, detailed guidelines regarding foreign material and industry best practices for actuating relays following alarm checks.
Corrective Action References: AR 2517978, 2518338
Performance Assessment:
Performance Deficiency: The licensees failure to perform an adequate foreign material closeout inspection was a performance deficiency. Specifically, PTN failed to perform WO 409550189 instruction step 4.2 to satisfactorily perform a FME closeout inspection for the 4A EDG relay and metering panel as indicated by tape holding the 160-voltage differential relay in an actuated position. The WO classified the work as a foreign material exclusion area 2, which required the use of licensee procedure, MA-AA-101-1000, Foreign Material Exclusion Program, Revision 33. Section 4.6.1 states, Prior to closing an electrical cabinet, ensure all parts are accounted for ensure that nothing is stored in the cabinet. Due to the blown fuse in the voltage sensing line and the taped relay, the 4A 4kV bus locked out and an automatic reactor trip of Unit 4 coincident with an automatic SI occurred.
Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Human Performance attribute of the Initiating Events cornerstone and adversely affected the cornerstone objective to limit the likelihood of events that upset plant stability and challenge critical safety functions during shutdown as well as power operations. Specifically, the performance deficiency led to a complicated reactor trip on Turkey Point Unit 4.
Significance: The inspectors assessed the significance of the finding using IMC 0609 Appendix A, The Significance Determination Process (SDP) for Findings At-Power. IMC 0609 Appendix A, exhibit 1, Section C.1 requires, Go to Detailed Risk Evaluation section because the degraded condition resulted in the 4A 4kV safety-related bus to lock out, which led to the loss of A train safeguards equipment. A regional senior reactor analyst (SRA)conducted a detailed risk assessment of the degraded condition. The SRA used SAPHIRE 8, Version 8.2.11; the Turkey Point Units 3&4 SPAR Model, Version 8.81, dated 7/28/2023; NRC IMC 0609, Appendix A; and the Risk Assessment Standardization Project Manual, Volume 1.
The SRA used the guidance in Risk Assessment Standardization Project Manual Volume 1 to evaluate the issue as an event assessment since the competent which had the performance deficiency was not considered operable due to test and maintenance during the time the performance deficiency existed, and the event happened during testing of this component.
The dominant accident sequence was a loss of the 4A vital bus, a failure of the reactor protection system resulting in an ATWS, an unfavorable moderator temperature coefficient, and one PORV unavailable due to the block valve being closed at power. The resulting CCDP was less than 1E-6 thus the finding characterized as a finding of very low safety significance (Green). The event was also evaluated for large early release frequency (LERF)considerations using NRC IMC 0609 Appendix H.
Cross-Cutting Aspect: H.13 - Consistent Process: Individuals use a consistent, systematic approach to making decisions. Risk insights are incorporated as appropriate. Specifically, the licensee failed to ensure appropriate FME area 2 work practices were implemented in accordance with work order task instructions. This resulted in the 160-voltage differential relay not restored to its as-found configuration, leading to a condition that caused a Unit 4 reactor trip.
Enforcement:
Violation: Improved Technical Specification (ITS) section 5.4.1 requires, in part, that written procedures shall be established, implemented, and maintained as covered in the Quality Assurance Topical Report (QATR), which includes procedures listed in Regulatory Guide 1.33, Revision 2, Appendix A, February 1978. Section 9a specifies that maintenance that can affect the performance of safety-related equipment should be properly pre-planned and performed in accordance with written procedures, documented instructions or drawings. The licensee implements ITS 5.4.1 requirements in procedure MA-AA-101-1000, Foreign Material Exclusion Program, Revision 33. Step 4.6.1 states, in part, Prior to closing an electrical cabinet, ensure all parts are accounted for ensure that nothing is stored in the cabinet.
Contrary to the above, on June 21, 2025, the licensee failed to implement procedures recommended by Regulatory Guide 1.33 as described in the QATR and ITS 5.4.1.
Specifically, PTN failed to perform WO 409550189 instruction step 4.2 to satisfactorily implement MM-AA-101-1000. As a result, tape was left on the 160-voltage differential relay contact after alarm testing resulting in the 4A 4kV safety bus lockout.
Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Condition Prohibited by TS due to Inoperable Power Range Nuclear Instrument Cornerstone Severity Cross-Cutting Aspect Report Section Not Applicable Severity Level IV NCV 05000250/2025003-03 Open/Closed Not Applicable 71111.12 The inspectors identified a Severity Level IV NCV of Turkey Point Unit 3 Improved Technical Specification 3.3.1, Reactor Trip System Instrumentation, for the failure to complete required actions for an inoperable power range nuclear instrument (NI). Specifically, the licensee entered Mode 2 and started up the reactor following a refueling outage with one power range neutron flux low channel inoperable from November 14-19, 2024, and the required channel was not placed in trip or the required mode change made. Consequently, the licensee entered a condition prohibited by technical specifications.
Description:
Turkey Point performs cable testing on each power range detector during a refueling outage. The testing is completed in accordance with 0-CMI-059.10, Excore Neutron Detector Post Installation Inspection and Testing early in the refueling outage after reactor shutdown and later in the outage after the refueling cavity is drained. Work order (WO)40880658-01 was completed during the Unit 3 refueling outage on 10/17/2024 and did not identify any issues with power range cables. The second test performed on 11/6/2024 (WO 40880658-02) measured significantly lower resistance readings in the cable for power range channel III, N-3-43. Instrument & control (I&C) identified the cable resistance readings were lower than the acceptance criteria and initiated action request (AR) 02500812 and work request (WR) 94267348 to evaluate and correct the issue. A mode hold assignment was issued to engineering for further evaluation. Engineering reviewed prior evaluations (AR 2305849 and 2308296) to justify the low resistance readings as acceptable for use as is and removed the mode hold without performing any corrective actions.
The inspectors performed an independent review of cable testing history. Previous outages in 2021, 2020, 2019, 2017 identified similar instances of degraded or low cable resistance readings in the power range detectors, as documented in ARs 2233079, 2305849, 2308296, 2410943, and 2421599. Most of these ARs documented a drop in resistance readings during the first test early in the outage, while the second test late in the outage documented the resistance readings returned to acceptable range. The engineering evaluation in AR 2305849/2308296 documented a table with a trend of resistance readings for the center conductor to inner shield insulation and showed typically the first measurement (early outage)was low but the second measurement (late outage, post-drain down) returned to acceptable values. Due to the insulation resistance values substantially increasing, thus meeting the acceptance criteria, no further action was deemed necessary (i.e., no corrective actions taken after acceptable value obtained). This was not the case during this event. The first (early outage) resistance readings were acceptable, but the later outage readings were not within the acceptance criteria.
AR 2410943 documented low cable resistance readings late in the outage in November 2021 and subsequent troubleshooting revealed moisture intrusion in junction box internals. Once a vacuum pump was used to dry out any connectors and the box, the cable resistance readings returned to acceptable values. Therefore, moisture intrusion was a known occurrence in these cables, as indicated by low cable resistance measurements and previous station operating experience (OE) was not considered to justify not taking corrective action in this event. Since corrective action was not taken to remove the moisture in the cabling (a condition adverse to quality) before starting up the reactor, N-3-43 was declared operable on 11/14/2024, but in a degraded condition.
The licensee entered Mode 2 on 11/14/2024 and proceeded with power ascension. During power ascension operations and I&C observed unexpected detector response from N-3-43A (upper detector), until ultimately the detector could not be calibrated or gain adjusted at 63 %
reactor power on 11/19/2024. N-3-43 was declared inoperable, operations entered LCO 3.3.1 and completed the required action to trip the associated bistables.
Corrective Actions: A Failure Investigation Process (FIP) team found that N-3-43A signal cable in containment had water intrusion because of condensation during the refueling outage, which caused a change in cable impedance. After the cable was purged of water, a healthy signal returned to N-3-43A and the N-3-43 channel was calibrated and returned to service on 11/22/2024. A past operability evaluation was performed and identified that, from 11/14/2024 to 11/19/2024, N-3-43 was inoperable for the low power range trip, Function 2.b of Table 3.3.1-1 of Improved Technical Specification (ITS) 3.3.1, and the action statements were not completed as required. The license submitted an event report to the NRC on 1/15/2025 under 10 CFR 50.73(a)(2)(i)(B), a condition prohibited by ITS.
Corrective Action References: ARs 02500812, 02501747, 02501844, 02501865, 2502363, 2502365
Performance Assessment:
The NRC determined that any associated Reactor Oversight Process (ROP) aspects would be Green or minor; therefore, this violation is addressed using traditional enforcement in accordance with IMC 0612 Appendix B, Block TE3.
Enforcement:
In accordance with IMC 0612 Appendix B, when a traditional enforcement violation is present, the default screening path is to pursue only the traditional enforcement aspect given any ROP aspect would be Green or minor.
Severity: This violation is characterized as a Severity Level (SL) IV violation based on its similarity to SL IV example 6.1.d.1 in the Enforcement Policy. The inspectors also reviewed NRC Enforcement Policy, Section 2.2.1, "Factors Affecting Assessment of Violations," which states, in part, that in determining the appropriate enforcement response to a violation, whenever possible, the NRC uses risk information in assessing the safety or security significance of violations and assigning severity levels. The inspectors determined the issue to be of very low safety significance because during the period three redundant channels were operable and fully capable of performing their safety functions, so the reactor trip function was not lost during N-3-43 channel inoperability.
Violation: Turkey Point Nuclear Station, Unit 3 Improved Technical Specification Limiting Condition of Operation 3.3.1, requires, in part, that reactor trip system (RTS) instrumentation for each function in Table 3.3.1-1 shall be operable in the modes of applicability as defined in Table 3.3.1-1. Table 3.3.1-1 lists the low power range as Function 2.b and requires entry into Condition E when any of the four channels are inoperable and requires placing the inoperable channel in trip within six hours. If the required actions for Condition E are not met within the established completion time, Condition T requires the Unit to be in Mode 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
Contrary to the above, from November 14 to November 19, 2024, the licensee failed to identify the low power range trip function associated with RTS to be inoperable when Unit 3 entered Mode 2. Because the licensee did not recognize the inoperability of the low power trip function of N-3-43, they failed to complete the required actions in TS 3.3.1, Conditions E and T, within the established completion times.
Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
4C Component Cooling Water Auto-Start Signal Inoperable Cornerstone Severity Cross-Cutting Aspect Report Section Not Applicable Severity Level IV NCV 05000251/2025003-04 Open/Closed Not Applicable 71111.15 A self-revealed SL IV NCV of ITS 3.3.2, Engineered Safety Features Actuation System (ESFAS) Instrumentation, limiting condition for operations (LCO) was identified when the licensee failed to ensure both trains of ESFAS auto-start feature for the 4C component cooling water (CCW) pump were operable.
Description:
On June 4, 2025, after completion of the 4B CCW pump motor inspection, the licensee attempted to rack in the 4B CCW pump breaker, 4AB13. During the rack in process, the breaker came out of alignment, resulting in it being stuck in an intermediate position.
Action request (AR) 2516841 was written to document the issue. The licensee determined that the 4B CCW pump was inoperable. Typically, the 4C CCW pump serves as a swing pump, a backup pump to either CCW train A or B. With the 4B CCW pump inoperable and unavailable, the 4C CCW pump was relied upon to perform the required safety functions, including the ability to automatically start on a loss of offsite power (LOOP) or safety injection (SI). Initial investigation noted an 8-inch airgap between the secondary contacts which led the site to believe that 4AB13 was racked down enough for the 4C CCW pump to automatically start during a LOOP or SI. A prompt operability determination was requested to confirm operability of the 4B 4kV bus and the 4C CCW pump auto-start feature.
On June 9, 2025, the licensee continued troubleshooting breaker 4AB13 per WO 41020936.
Field action request 02 was performed, and electrical maintenance personnel discovered that the 152/HH switch, associated with 4B CCW breaker position, was left in an intermediate state. The 5-5T contact associated with the 152/HH switch was found locked open. This would have prevented the auto-start circuit from energizing the 4C CCW pump if actuated from the 4B emergency load sequencer in the event of a LOOP or SI. Therefore, the auto-start feature associated with the 4C CCW pump was disabled and its associated ESFAS signal was inoperable. A past operability review was performed under AR 2517143 for the B train 4C CCW pump auto-start feature. The past operability review (POR) determined the B train of 4C CCW ESFAS signal was inoperable from June 4, 2025, until June 9, 2025.
Licensee Event Report (LER) 05000251/2025-003-00, 4B Component Cooling Pump and its Associated Breaker Inoperable, (ADAMS Accession Number ML25216A111) was submitted by the licensee for this event. The LER determined the B train of ESFAS was inoperable from June 4 to June 9, 2025, and that ITS LCO 3.3.2 Condition C and Condition O, required action statements, were not completed as required.
Corrective Actions: A jumper was installed to restore the AutoStart feature of the 4C CCW pump.
Corrective Action References: Condition reports 2516841 and 2517143
Performance Assessment:
The NRC determined this violation was not reasonably foreseeable and preventable by the licensee and therefore is not a performance deficiency.
Enforcement:
The ROPs significance determination process does not specifically consider the regulatory process impact in its assessment of licensee performance. Therefore, it is necessary to address this violation which impedes the NRCs ability to regulate using traditional enforcement to adequately deter non-compliance.
Severity: This violation is characterized as an SL IV violation based on its similarity to SL IV example 6.1.d.1 in the Enforcement Policy. The inspectors also reviewed NRC Enforcement Policy, Section 2.2.1, "Factors Affecting Assessment of Violations," which states, in part, that in determining the appropriate enforcement response to a violation, the NRC considers, whenever possible, risk information in assessing the safety or security significance of violations and assigning severity levels. The inspectors determined the issue to be of very low safety significance because the 4C CCW pump remained capable of a manual start, therefore the function was not lost.
Violation: Turkey Point ITS 3.3.2, "Engineered Safety Features Actuation System (ESFAS)
Instrumentation," Condition C, requires that with one automatic actuation logic train inoperable, the train be restored to operable status within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. And Condition O requires that if the associated completion time of Condition C is not met, the unit be in Mode 3 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and be in Mode 4 within 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br />.
Contrary to the above, from June 4 to June 9, 2025, with one automatic actuation logic train inoperable, train B of the ESFAS auto-start function to the 4C CCW pump, the licensee did not take the required actions of ITS 3.3.2 Condition C or O, to restore the train to operable status or be in Mode 3 or 4 within the required timeframe.
Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified that no proprietary information was retained or documented in this report.
- On October 9, 2025, the inspectors presented the integrated inspection results to Mr.
Michael Durbin, Site Vice President and other members of the licensee staff.
THIRD PARTY REVIEWS The inspectors reviewed Institute on Nuclear Power Operations reports that were issued during the inspection period.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Corrective Action
Documents
Resulting from
Inspection
action request
20831
Miscellaneous
Equipment
Qualification
Documentation
Package 3.0
Automatic Switch Company Solenoid Valves
3-OSP-075.1
Auxiliary Feedwater Train 1 Operability Verification
3-OSP-075.5
Auxiliary Feedwater System Flowpath Verification
Procedures
4-OSP-300.2
Pre-Staging Equipment and Alternate Shutdown Panel
4C264 Switch and Instrumentation Alignment Check
Corrective Action
Documents
Resulting from
Inspection
action request
21521, 2523558
Drawings
5610-A-178
Fire Barriers and Penetrations Zone 068-F
0-ADM-016.2
Fire Brigade Program
0-AM-016.3
Fire Protection Impairments (FPI)
0-ONOP-016.10
Safe Shutdown Manual Actions
0-SFP-016.1
Fire Barrier Penetration Seal Inspection
0-SME-091.4
Fire and Smoke Detection System Annual Test Circuits 7, 8,
20, 21, 22, 23, and 39
2/15/22
PFP-4-TB-18
Unit 4 Turbine Building
Procedures
Unit 3&4 Auxiliary Building
Corrective Action
Documents
action requests
233079, 2410712, 2410943, 2421599, 2461340, 2471827,
2471836, 2305849, 2308296, 2502365
5614-E-28
Electrical Auxiliaries Diesel Generator 4K4A Governor
Control
5614-M-16A-24
Emergency Diesel Generator 4K4A
Drawings
5614-M-16A-27
Emergency Diesel Generator 4K4A Relay, Switch,
Equipment and Contact, Location and Settings
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
005-EB-01
Maintenance Rule Scope Evaluation System 005 Lower
Medium Voltage System - 4.16KV (Class IE Power System)
08/16/2016
2-EK-01
Final Scope Evaluation System 022-EK Emergency Diesel
Generators
2/01/2018
Miscellaneous
GEK-41831
General Electric Instruction Booklet GEK-41831 for Voltage
Balance Relay type CFVB
0-PME-005.22
Testing and Independent Verification of Operational Trip Test
0-PME-023.07
Testing and Independent Verification of General Electric
Type CFVB Relays
0A
4-OP-023.1
Diesel Generator Test for Voltage Regulator or Governor -
Adjustment or Replacement
Maintenance Rule Program Administration
Procedures
Foreign Material Exclusion Procedure
Work Orders
work order 40880977, 40805819, 40724329, 40637812, 40542902
0-ADM-225
Online Risk Assessment and Management
Procedures
Guarded Equipment
Drawings
5614-E-25 Sheet
2C
Reactor Auxiliaries Component Cooling Water Pump 4C
Breaker 4AD04
4-OSP-030.1
Component Cooling Water Pump Inservice Test
5610-030-DB-001
Component Cooling Water System
5610-049-DB-001
Reactor Protection System and Engineered Safety Features
Actuation System (Vol. 8)
5610-050-DB-002
Turkey Point Units 3 and 4 Residual Heat Removal System
Component Design Requirements
01/02/2024
Procedures
Issue Investigation
Work Orders
WO 40983040, 40969822, 40975206
Corrective Action
Documents
action requests
2510426, 2510609, 2510432, 2510642, 2510455, 2514764
Work Orders
work orders
41009406, 41012146, 40792046, 40849583, 40953912,
40984277
Corrective Action
Documents
action request
22718
Procedures
0-GME-005.01
4.16KV Equipment Grounding and Testing
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
0-PME-019.04
Intake Cooling Water Pump Motor Changeout
4-OP-023.1
Diesel Generator Test for Voltage Regulator or Governor -
Adjustment or Replacement
01/23/2024
Shipping Records
PTN REC
258824
Receipt Inspection Report
09/04/2025
Work Orders
work orders
40651848, 40998731, 40976919, 41026382, 41029241
71151
Procedures
0-ADM-032
NRC Performance Indicators Turkey Point
Corrective Action
Documents
action requests
2517433, 02511460, 02515920, 02514596, 02518758,
2522568, 02516105, 02521402, 02524074, 02522678,
2524073, 02521521, 02514515, 02514337, 02521845,
2514019, 02523721, 02516099
Procedures
3-SMM-016.6
Fire Door Inspection Unit 3/Common
Corrective Action
Documents
Resulting from
Inspection
action requests
2516604