IR 05000335/2025002
| ML25217A097 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie, 07200061  |
| Issue date: | 08/06/2025 |
| From: | Shawn Smith NRC/RGN-II/DORS/PB6 |
| To: | Coffey R Florida Power & Light Co |
| References | |
| IR 2025001, IR 2025002 | |
| Download: ML25217A097 (1) | |
Text
SUBJECT:
SAINT LUCIE PLANT, UNITS 1 AND 2 - INTEGRATED INSPECTION REPORT 05000335/2025002 AND 05000389/2025002 AND 07200061/2024001 AND 07200061/2025001
Dear Robert Coffey:
On June 30, 2025, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Saint Lucie Plant, Units 1 and 2. On July 8, 2025, the NRC inspectors discussed the results of this inspection with Mr. Carlos Santos, Site Vice President and other members of your staff. The results of this inspection are documented in the enclosed report.
Two findings of very low safety significance (Green) are documented in this report. Two of these findings involved violations of NRC requirements. We are treating these violations as non-cited violations (NCVs) consistent with Section 2.3.2 of the Enforcement Policy.
A licensee-identified violation which was determined to be of very low safety significance is documented in this report. We are treating this violation as an NCV 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 Saint Lucie Plant, Units 1 and 2.
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 Saint Lucie Plant, Units 1 and 2.
August 6, 2025 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. 05000335 and 05000389 and 07200061 License Nos. DPR-67 and NPF-16
Enclosure:
As stated
Inspection Report
Docket Numbers:
05000335, 05000389, and 07200061
License Numbers:
Report Numbers:
05000335/2025002, 05000389/2025002, 07200061/2024001, and
07200061/2025001
Enterprise Identifier:
I-2025-002-0022; I-2024-001-0150; I-2025-001-0087
Licensee:
Florida Power & Light Company
Facility:
Saint Lucie Plant, Units 1 and 2
Location:
Jensen Beach, FL 34957
Inspection Dates:
March 31, 2025 to June 30, 2025
Inspectors:
J. Baptist, Senior Resident Inspector
B. Bowker, Senior Reactor Inspector
S. Bruneau, Resident Inspector
P. Cooper, Senior Reactor Inspector
T. Griffin, Project Engineer
E. Morris, Senior Resident Inspector
S. Roberts, Senior Project Engineer
S. Sandal, Senior Reactor Analyst
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 Saint Lucie Plant, Units 1 and 2, 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. A licensee-identified non-cited violation is documented in report section: 7115
List of Findings and Violations
Failure to Evaluate Cask Crane Support Structure in accordance with AISC Cornerstone Significance Cross-Cutting Aspect Report Section Barrier Integrity Green NCV 05000389/2025002-01 Open/Closed None (NPP)60856 A finding of very low safety significance (Green) and an associated non-cited violation (NCV)of Title 10 of the Code of Federal Regulations (CFR) Part 50, Appendix B, Criterion III,
Design Control, was identified by the inspectors for the licensees failure to establish adequate measures to assure that appropriate quality standards were specified and included in the design documents. Specifically, the site incorrectly evaluated the acceptability of the Seismic Category I crane support structure that supports the single-failure-proof Cask Handling Crane based on the material yield stress documented in the certified material test results rather than the specified material yield stress as described in the American Institute for Steel Construction (AISC) methodology.
Failure to Maintain Flex 480V Diesel Generator Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000389,05000335/2025002-02 Open/Closed
[P.2] -
Evaluation 71152S The inspectors identified a Green finding and associated NCV of 10 CFR 50.155(c)(1) when the licensee failed to maintain FLEX equipment's capability to respond to beyond design basis external events.
Additional Tracking Items
Type Issue Number Title Report Section Status LER 05000335/2025-001-01 LER 2025-001-01 for St.
Lucie Unit 1, Safety Injection Tank Above Technical Specifications Limit 71153 Closed LER 05000335/2025-001-00 LER 2025-001-00 for St.
Lucie, Unit 1, Safety Injection Tank Above Technical Specifications Limit 71153 Closed
LER 05000335/2024-002-00 LER 2024-02-00 for St.
Lucie, Unit 1, Manual Reactor Trip Due To 3 CEA's Dropping Into Reactor Bottom 71153 Closed
PLANT STATUS
Unit 1 and Unit 2 began the inspection period at or near rated thermal power. On April 15, 2025, Unit 1 power was reduced to 15% due to a hydraulic oil leak in the turbine control system. Unit 1 was returned to rated thermal power on April 18,
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) (4 Samples)
The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:
- (1) Unit 1 1A charging pump while the 1C charging pump was out of service for scheduled maintenance. Inspection completed on April 9, 2025.
- (2) Unit 1 1A emergency diesel generator (EDG) alignment while the 1B EDG was out of service for scheduled maintenance. Inspection completed on April 21, 2025.
- (3) Unit 2 2A charging pump while the 2B charging pump was out of service for scheduled maintenance. Inspection completed on April 22, 2025.
- (4) Unit 1 1B EDG alignment while the 1A EDG was out of service for scheduled maintenance. Inspection completed on May 6, 2025.
71111.05 - Fire Protection
Fire Area Walkdown and Inspection Sample (IP Section 03.01) (5 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) Unit 1 fire zone 5, component cooling water (CCW) on April 15, 2025
- (2) Unit 1 fire zone 6, 1A EDG on April 15, 2025
- (3) Unit 1 fire zone 77 and 78, electrical penetration room 1A and 1B on April 16, 2025
- (4) Unit 1 fire zone 31, shutdown heat exchanger 1B on April 16, 2025
- (5) Unit 1 fire zone 7, 1B EDG on May 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 unannounced fire drill on April 25, 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 2 2A EDG run and reactor coolant temperature channel calibrations on April 7, 2025, restoration of Unit 1 ventilation system on April 9, 2025, Unit 1 power reduction to 15% in response to a hydraulic oil leak in the turbine control system on April 15, 2025, and Unit 1 power increase following repairs to turbine control system hydraulic oil leak on April 16, 2025.
Licensed Operator Requalification Training/Examinations (IP Section 03.02) (1 Sample)
- (1) The inspectors observed and evaluated a licensed operator continuing training evaluation in the control room simulator that included dropped control rods, rapid downpower, loss of offsite power, and a loss of coolant accident on May 27, 2025.
71111.12 - Maintenance Effectiveness
Maintenance Effectiveness (IP Section 03.01) (1 Sample)
The inspectors evaluated the effectiveness of maintenance to ensure the following structures, systems, and components (SSCs) remain capable of performing their intended function:
- (1) Unit 2 2A charging pump check accumulator pressure completed April 23, 2025 (Work Order (WO) 40981266)
Quality Control (IP Section 03.02) (1 Sample)
The inspectors evaluated the effectiveness of maintenance and quality control activities to ensure the following SSC remains capable of performing its intended function:
- (1) Unit 1 1B EDG 18-month preventive maintenance material, review completed April 24, 2025 (WO 40963332)
71111.13 - Maintenance Risk Assessments and Emergent Work Control
Risk Assessment and Management Sample (IP Section 03.01) (6 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 2 elevated risk while 2A turbine cooling water pump was out of service for planned maintenance during the week of April 7, 2025
- (2) Unit 1 elevated risk while the 1B EDG was out of service for planned maintenance during the week of April 21, 2025
- (3) Unit 2 elevated risk while the 2B charging pump was out of service for planned maintenance on April 22, 2025
- (4) Unit 1 elevated risk while the 1B startup transformer was out of service for planned maintenance during the week of April 28, 2025
- (5) Unit 1 elevated risk while the 1A EDG was out of service for planned maintenance during the week of May 5, 2025
- (6) Unit 1 elevated risk while the 1AB 4KV electrical bus was out of service for corrective maintenance during the week of May 26, 2025
71111.15 - Operability Determinations and Functionality Assessments
Operability Determination or Functionality Assessment (IP Section 03.01) (6 Samples)
The inspectors evaluated the licensee's justifications and actions associated with the following operability determinations and functionality assessments:
- (1) Unit 1 through-wall leak on bottom of the 1A intake cooling water (ICW) header line I-30"-CW-90 downstream of flange joining to line I-30"-CW-21, review completed April 4, 2025 (action request (AR) 2511102)
- (2) Unit 1 component cooling water pump 1A and 1C discharge piping spring can supports identified with broken springs, review completed April 11, 2025 (ARs
===2510811 and 2510812)
- (3) Unit 2 2A charging pump stopped unexpectantly during testing, review completed April 14, 2025 (AR 2513235)
- (4) Unit 1 1B EDG soakback pump piping oil leak, review completed April 15, 2025 (AR 2513332)
- (5) Unit 2 control room air handling unit HVA/ACC-3B low oil level, review completed April 16, 2025 (AR 2513269)
- (6) Unit 1 1A ICW pump identified water leak, review completed May 7, 2025 (AR 2514684)
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 or permanent modifications:
- (1) Unit 1 replacement of HVE-6A motor with qualified replacement, review completed on April 4, 2025 (Engineering Change 299543)
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)===
(1)1-OSP-25.09A, "Train A Emergency Core Cooling System Ventilation Surveillance,"
following planned maintenance on HVE-9A. Review completed April 10, 2025. (WO
===40964205) (2)1-NOP-02.02, "Charging and Letdown," following replacement of Unit 1 A charging pump discharge relief valve V2326. Review completed on April 11, 2025. (WO 40970102)
(3)0-OSP-83.04B, "Periodic Testing of the FLEX 480V Diesel Generator B," following corrective maintenance to the electronic control unit and cooling water system.
Review completed on April 14, 2025. (WO 40973648)
(4)1-OSP-02.01A, "1A Charging Pump Code Run," following corrective maintenance on 1A charging pump. Review completed on April 21, 2025. (WO 41015412)
(5)1-OSP-59.01B, "1B Emergency Diesel Generator Monthly Surveillance," following 1B EDG 18 month planned preventative maintenance. Review completed on April 24, 2025 (WO 40982626)
(6)2-CME-02.02, "Overhaul of Charging Pump Motors CHG PP-2A, 2B, & 2C," following replacement of Unit 2 2B charging pump motor. Review completed April 26, 2025.
(7)2-NOP-14.02, "Component Cooling Water System Operation," following planned preventative maintenance on Unit 2 2C CCW pump. Review completed April 29, 2025. (WO 402000689)
Surveillance Testing (IP Section 03.01)===
- (1) ADM-09.25, "Surveillance Frequency Control Program," Attachment 3, "Unit 1 Surveillance Requirements," for safety injection tank water volume verified within limits, completed on April 23, 2025 (2)2-OSP-59.01B, "2B Emergency Diesel Generator Monthly Surveillance," completed on April 28, 2025 (3)0-OSP-37.01, Emergency Cooling Water Canal - Periodic Test," completed on May 1, 2025 (4)2-OSP-09.01C, "2C Auxiliary Feedwater Pump Code Run," completed on May 8,
OTHER ACTIVITIES - BASELINE
===71151 - Performance Indicator Verification The inspectors verified licensee performance indicators submittals listed below:
BI01: Reactor Coolant System (RCS) Specific Activity Sample (IP Section 02.10)===
- (1) Unit 1 (March 1, 2024, through March 31, 2025)
- (2) Unit 2 (March 1, 2024, through March 31, 2025)
BI02: RCS Leak Rate Sample (IP Section 02.11) (2 Samples)
- (1) Unit 1 (March 1, 2024, through March 31, 2025)
- (2) Unit 2 (March 1, 2024, through March 31, 2025)
71152A - Annual Follow-up Problem Identification and Resolution Annual Follow-up of Selected Issues (Section 03.03)
The inspectors reviewed the licensees implementation of its corrective action program related to the following issues:
- (1) Diverse and flexible coping strategy (FLEX) 480V diesel generator B and C failed to run during full load test (AR 2509060) was selected for follow-up to verify licensee's corrective actions were adequate to resolve the deficiencies and mitigate recurrence of the FLEX 480V diesel generators failures, review completed May 30, 2025.
- (2) NRC inspectors conducted a Problem Identification and Resolution (PI&R) inspection sample with a focus on safety conscious work environment (SCWE) the week of June 16, 2025, as a follow-up to issues identified in Saint Lucie Plant, Units 1 & 2 - Biennial PI&R Inspection Report 05000335/2024011 and 05000389/2024011 (ADAMS Accession No. ML24262A044) issued on September 18, 2024. Prior to this sample, inspectors documented PI&R samples with a focus on safety culture in Saint Lucie Plant, Units 1 and 2 - Integrated Inspection reports 05000335/2024004 and
===05000389/2024004 (ADAMS Accession No. ML25029A238) and 05000335/2025001 and 05000389/2025001 (ADAMS Accession No. ML25114A129) to determine whether actions taken by the licensee addressed the SCWE concerns identified during the PI&R inspection.
During the June 2025 inspection, NRC staff interviewed senior licensed operators and other personnel at various levels within the Operations department. Results indicated that employees were generally aware of their responsibility and felt empowered to raise nuclear safety and quality concerns. Inspectors did not find any evidence that public safety concerns went unreported and found that the licensee had taken meaningful and sustained actions to promote and maintain a healthy SCWE following the previously identified work environment concerns in the Operations department. Most individuals expressed confidence that their concerns would be taken seriously and addressed appropriately. The feedback was consistent with recent licensee internal SCWE assessments and organizational health surveys reviewed during the inspection.
Corrective actions taken in response to the SCWE issues identified in the September 2024 NRC inspection report were thorough and fully implemented. These included organizational changes, targeted communication from senior leadership, SCWE training for supervisory personnel, and focused employee engagement efforts in the affected departments. Observations of daily supervisory status meetings identified a commitment to awareness of industry best practices and reinforced the traits of a healthy nuclear safety culture. The licensee also conducted a follow-up organizational health discussion to verify the effectiveness of the corrective actions. Results showed improved confidence in employee perceptions of management support and freedom to raise concerns, further supporting the conclusion that the SCWE had improved.
Supervisors and managers also demonstrated an understanding of SCWE principles and consistently articulated an expectation that concerns should be raised promptly.
Observations of routine work activities supported the conclusion that management fosters open communication and regularly reinforces the importance of a questioning attitude. Employees described several instances where concerns were elevated through normal supervisory channels or the Employee Concerns Program (ECP), and most characterized those interactions as professional and constructive. No interviewees reported fear of reprisal.
Following the 2024 PI&R inspection, the NRC communicated plans to conduct Inspection Procedure (IP) 93100, "Safety-Conscious Work Environment Issue of Concern Follow-up," to evaluate the effectiveness of the sites proposed corrective actions. However, based on ongoing NRC inspection activities and review of updates to site policies, staff communications, ongoing training, independent monitoring, process improvements, and management accountability, the NRC has concluded that an IP 93100 inspection is not warranted at this time. The licensee has taken clear, timely, and measurable steps to address the previously identified concerns and has demonstrated a commitment to maintaining an open environment for raising safety concerns. The NRC will continue to monitor the safety culture as part of the agencys baseline inspection program, which includes daily observations by resident inspectors and periodic sampling through regional inspections.
71152S - Semiannual Trend Problem Identification and Resolution Semiannual Trend Review (Section 03.02)===
- (1) The inspectors reviewed the licensees corrective action program for potential adverse trends associated with electrical fuse failures, that might be indicative of a more significant safety issue. No adverse trend was identified.
71153 - Follow Up of Events and Notices of Enforcement Discretion Event Report (IP Section 03.02)
The inspectors evaluated the following licensee event reports (LERs):
- (1) LER 05000335/2025-001-00 and 2025-001-01, Safety Injection Tank Above Technical Specifications Limit (ADAMS Accession No. ML25085A185).
The inspection conclusions associated with this LER are documented in this report under the Inspection Results section as a licensee identified violation. This LER is Closed.
- (2) LER 05000335/2024-002-00, Manual Reactor Trip Due to 3 CEA's Dropping Into Reactor Bottom (ADAMS Accession No. ML25013A038). The inspectors determined that it was not reasonable to foresee or correct the cause discussed in the LER therefore no performance deficiency was identified. The inspectors did not identify a violation of NRC requirements. This LER is Closed.
Reporting (IP Section 03.05) (1 Sample)
The inspectors evaluated the following licensees event reporting determinations to ensure it complied with reporting requirements.
- (1) The inspectors reviewed AR 2514429 related to a notification to the NRC per 10 CFR 50.72(b)(2)(xi), non-emergency event, for a healthy smalltooth sawfish (endangered species) that was taken from the plant's intake and released in good condition on April 15,
OTHER ACTIVITIES
- TEMPORARY INSTRUCTIONS, INFREQUENT AND ABNORMAL
===60853 - Onsite Fabrication of Components and Construction of an Independent Spent Fuel Storage Installation 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) 2690, Inspection Program for Storage of Spent Reactor Fuel and Reactor-Related Greater-than-Class C Waste at Independent Spent Fuel Storage Installations (ISFSI) and for 10 CFR Part 71 Transportation Packagings."
Pad Construction Inspection [02.01, 02.04, 02.05, 02.06]===
- (1) The existing ISFSI pads were designed and constructed to store TN NUHOMS Horizontal Storage Modules (HSMs). The inspectors verified that the licensee completed additional evaluations which establish that the ISFSI storage pads and areas have been designed to adequately support the static and dynamic loads of the HOLTEC HI-STORM FW system, considering potential amplification of earthquakes through soil-structure interaction, and soil liquefaction potential or other soil instability due to vibratory ground motion.
===60854 - Preoperational Testing Of An ISFSI The inspectors evaluated the licensee's performance during NRC observed preoperational testing and training exercises to verify that the licensee has developed, implemented, and evaluated preoperational testing activities to safely load spent fuel from the spent fuel pool (SFP) into a dry storage system (DSS), transfer the loaded DSS to the independent spent fuel storage installation (ISFSI), and retrieve spent fuel from an ISFSI.
Preoperational Testing Of An ISFSI===
- (1) The inspectors reviewed preoperational and operational procedures and verified that hold points and critical tasks are clearly marked. In accordance with NRC-issued certificate of compliance (CoC) No. 1032, Amendment 6 the inspectors observed the implementation of the following activities:
- December 9 - 13, 2024 at the Holtec Camden, NJ Facility:
o Multi-purpose canister (MPC) welding, non-destructive evaluation (NDE) inspections, pressure testing, draining, moisture removal by vacuum drying, and helium backfilling
- March 10 - 28, 2025 at the St. Lucie Nuclear Plant:
o Preparation of the HI-STORM FW MPC Storage System for fuel loading o
Moving the MPC and the transfer cask into the spent fuel pool or cask loading pool o
Transfer of the MPC from the transfer cask to the overpack o
Placement of the HI-STORM FW MPC Storage System at the ISFSI o
Selection and verification of specific fuel assemblies to ensure type conformance o
Loading specific assemblies and placing assemblies into the MPC (using a dummy fuel assembly), including appropriate independent verification o
Remote installation of the MPC lid and removal of the MPC and transfer cask from the spent fuel pool or cask loading pool Additionally, the inspectors evaluated the effectiveness of the licensees corrective actions and oversight (including contractor oversight), by reviewing the ISFSI quality assurance program, corrective actions documents, and records associated with the dispositioning of nonconforming conditions to ensure that issues were being properly identified, prioritized, and evaluated commensurate with their safety significance.
===60855 - Operation Of An ISFSI The inspectors performed a review of the licensees ISFSI activities to verify compliance with regulatory requirements.
Operation Of An ISFSI===
- (1) From March 31 - April 3, 2025, during the on-site inspection, the inspectors observed and reviewed licensee activities in each of the five safety focus areas including occupational exposure, public exposure, fuel damage, confinement, and impact to plant operations.
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. Additionally, the inspectors performed independent walkdowns of the heavy load lifting equipment, ISFSI storage pad, and the ISFSI haul path. The inspector also performed an independent radiation survey of the ISFSI pad.
===60856 - Review of 10 CFR 72.212(b) Evaluations The inspectors evaluated the licensees compliance with the requirements of 10 CFR 72.212.
Review of 10 CFR 72.212(b) Evaluations===
- (1) The inspectors reviewed the licensees written evaluations to determine if they were in accordance with 10 CFR 72.212(b)(5) and evaluated the conditions set forth in the CoC to determine if conditions had been met prior to use. The inspectors examined applicable reactor site parameters, such as hypothetical fire and explosions, tornadoes, wind generated missile impacts, seismic qualifications, lightning, flooding and temperature, to determine if they had been evaluated for acceptability with bounding values specified in the Updated Final Safety Analysis Report (UFSAR) and the NRC Safety Evaluation Report (SER). The inspectors also examined 50.59 evaluations related to the construction and operation of the ISFSI and plant interfaces to determine if they were performed and to determine if changes to certain facility design bases and FSAR commitments required prior NRC approval. The emergency plan, quality assurance program, training program, and radiation protection program were reviewed to determine if there was a decrease in effectiveness and if changes made required prior NRC approval.
INSPECTION RESULTS
Failure to Evaluate Cask Crane Support Structure in accordance with AISC Cornerstone Significance Cross-Cutting Aspect Report Section Barrier Integrity Green NCV 05000389/2025002-01 Open/Closed None (NPP)60856 A finding of very low safety significance (Green) and an associated non-cited violation (NCV)of Title 10 of the Code of Federal Regulations (CFR) Part 50, Appendix B, Criterion III, Design Control, was identified by the inspectors for the licensees failure to establish adequate measures to assure that appropriate quality standards were specified and included in the design documents. Specifically, the site incorrectly evaluated the acceptability of the Seismic Category I crane support structure that supports the single-failure-proof Cask Handling Crane based on the material yield stress documented in the certified material test results rather than the specified material yield stress as described in the American Institute for Steel Construction (AISC) methodology.
Description:
The requirements for seismic design of the Seismic Category I Cask Handling Crane Support Structure are specified in Section 3.8.4.3.2.3 the licensees UFSAR where it states, in part. that the structural steel conforms to the AISC, Specification for the Design, Fabrication, and Erection of Structural Steel for Buildings, Seventh Edition.
The inspectors reviewed design calculation 2001-15060, U-2 Evaluation/ Design of Crane Support Structure Revision 1, approved on March 26, 2003, and noted the licensee stated, in part, that a Computer program is used to compute the maximum Interaction Coefficient (IC)
(ratio or the actual / allowable stress) of the frame members based on specified minimum yield strength for A36 material. If the interaction coefficient is greater than 1.0, then, the member is overstressed and will be reevaluated based on Certified Material Test Reports (CMTR) or will be replaced with new section with 50 ksi steel.
The inspectors reviewed the evaluation where several members of A36 material were preliminarily determined to be overstressed and were revaluated utilizing CMTR values ranging from 37.685 - 50.887 ksi versus the specified minimum yield stress of 36 ksi.
AISC design standards referenced in the USAR for the design of structural steel defined yield stress in its definition of a symbol section: Fy: Specified minimum yield stress of the type of steel being used, ksi. As used in this Specification, yield stress denotes either the specified minimum yield point (for those steels with a yield point) or specified minimum yield strength (for those steel without a yield point). The inspectors concluded that the use of material yield strength from CMTR data instead of material specified minimum yield stress to determine allowable bending stress was not in conformance with the AISC design standard.
Corrective Actions: The licensee initiated actions to reevaluate the crane support structure that will be utilized to inform future actions, including modifications, if needed.
Corrective Action References: AR 02517794, 2025 ISFSI Inspection - Cask Handling Crane
Performance Assessment:
Performance Deficiency: The inspectors determined that the failure to provide adequate design control measures to assure that appropriate quality standards were specified and included in the design documents was a performance deficiency. Specifically, the site incorrectly evaluated the acceptability of the Seismic Category I crane support structure that supports the single-failure-proof Cask Handling Crane based on the material yield stress documented in the certified material test results rather than the specified minimum material yield stress as described in the AISC methodology.
Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the SSC and Barrier Performance attribute of the Barrier Integrity cornerstone and adversely affected the cornerstone objective to provide reasonable assurance that physical design barriers protect the public from radionuclide releases caused by accidents or events. Specifically, compliance with AISC requirements ensured safety-related structures would function as designed during accident and maximum seismic conditions.
Significance: The inspectors assessed the significance of the finding using IMC 0609 Appendix A, The Significance Determination Process (SDP) for Findings At-Power. Using IMC 0609, Attachment 4, Initial Characterization of Findings, Table 2, the inspectors determined the finding affected the Barrier Integrity cornerstone because it was associated with the SFP. Based on answering No to questions A through E in Table 3, the inspectors determined the finding could be evaluated using IMC 0609 Appendix A, Exhibit 3, for the Barrier Integrity cornerstone screening questions. The inspectors determined the violation screened as Green by answering No to Questions E.1 through E.4 because the structural components designed using CMTR yield strength remained functional.
Cross-Cutting Aspect: Not Present Performance. No cross-cutting aspect was assigned to this finding because the inspectors determined the finding did not reflect present licensee performance.
Enforcement:
Violation: 10 CFR Part 50, Appendix B, Criterion III, Design Control, requires in part, that measures shall be established to assure that applicable regulatory requirements and the design basis are correctly translated into specifications, drawings, procedures, and instructions.
Contrary to the above since March 26, 2003, the licensee failed to correctly translate the licensing basis for the Seismic Category I crane support structure into specifications, drawings, procedures, and instructions. Specifically, the licensee incorrectly utilized the certified material test results instead of the specified minimum yield stress as described in the American Institute for Steel Construction (AISC), Specification for the Design, Fabrication, and Erection of Structural Steel for Buildings, Seventh Edition for the evaluation of the Seismic Category I crane support structure.
Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Failure to Maintain Flex 480V Diesel Generator Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000389,05000335/2025002-02 Open/Closed
[P.2] -
Evaluation 71152S The inspectors identified a Green finding and associated NCV of 10 CFR 50.155(c)(1) when the licensee failed to maintain FLEX equipment's capability to respond to beyond design basis external events.
Description:
Saint Lucie's (PSL) diverse and flexible coping strategy (FLEX) program requires three available 480V diesel generators to provide AC power for battery chargers, a charging pump, and other equipment for Unit 1 and Unit 2 during a FLEX extended loss of AC power event. PSL established a preventive and predictive maintenance program through procedure ADM-17.34, Diverse and Flexible Coping Strategies (FLEX) Program, Rev. 27, and FLEX-AA-100-1006, FLEX 480V Diesel (TAD1353GE and TAW1643GE), Rev. 4. which includes starting the three 480V diesel generators every six months with a full load test annually. A predictive maintenance program includes analyzing the radiator coolant annually.
On January 7, 2025, the C FLEX 480V diesel generator failed 37 minutes into the 1-hour full load run due to a failed electronic control unit. On February 13, 2025, the B FLEX 480V diesel generator automatically shutdown on high coolant temperature 15 minutes into the 1-hour full load run due to the radiator being plugged with corrosion. The previous successful tests of the FLEX 480V diesel generators occurred on January 31, 2024, full load and July 3, 2024, unloaded for the C FLEX 480V diesel generator and January 31, 2024, full load and July 3, 2024, unloaded for the B 480V diesel generator. The C Flex diesel was repaired and returned to available on March 14, 2025, and the B Flex diesel was repaired and returned to available on April 11, 2025. The simultaneous failures of two FLEX 480V diesel generators resulted in one of the two PSL units being incapable of implementing the Phase 2 AC power FLEX strategy if required for an exposure time of greater than 21 days.
Corrective Actions: Corrective Actions: The C Flex 480V diesel generator was repaired and successfully retested on March 4, 2025. The B FLEX 480V diesel generator was repaired and successfully retested on April 11, 2025.
Corrective Action References: ARs 2507914, 2505138, 2509060
Performance Assessment:
Performance Deficiency: The licensees failure to develop and implement testing and maintenance procedures to ensure that portable FLEX equipment is maintained in a manner to provide acceptable service in support of FLEX strategies was a performance deficiency.
Specifically, the diesel engine coolant analysis program established by PSL failed to identify and correct severe corrosion in the B FLEX 480V diesel generator which ultimately resulted in the diesel generator being incapable of supporting FLEX strategies due to overheating. ADM-17.34, Diverse and Flexible Coping Strategies (FLEX) Program, Rev. 27, Section 4.6.3 states in part that testing and maintenance procedures ensure that portable FLEX equipment is maintained in a manner to provide acceptable service in support of FLEX strategies.
Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Equipment Performance 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.
Significance: The inspectors assessed the significance of the finding using IMC 0609 Appendix A, The Significance Determination Process (SDP) for Findings At-Power. FLEX issues are addressed by Exhibit 2, with question E.2 directing to go to Detailed Risk Evaluation section because the finding did involve equipment credited in the PSL Phase 2 Flex providing AC power strategy such that the function could not be implemented in accordance with existing plant procedures and the exposure time was greater than 21 days.
A detailed risk evaluation was performed by a regional Senior Reactor Analyst using Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE) Version 8.2.12 and NRC Saint Lucie Unit 1 and Unit 2 Standardized Plant Analysis Risk (SPAR) models Version 8.83. The SPAR models were adjusted to reflect Saint Lucie Flexible Coping Strategy (FLEX) implementation for the site. A conditional analysis was carried out to evaluate the risk increase due to the unavailability of the B 480V FLEX Diesel Generator (DG). An exposure period of 247 days, including repair time, was used and no credit was provided in the analysis for recovery of B FLEX 480V DG. The dominant sequences involved weather-induced loss of offsite power initiators followed by failure of emergency diesel generators, failure of the FLEX diesel generators and failure to recover offsite electrical power. The overall risk of the finding was mitigated by the remaining capability of equipment available to respond to an extended loss of AC power. The analysis determined that the estimated increase in Core Damage Frequency (CDF) and Large Early Release Frequency (LERF) was less than 1E-06/year for delta-CDF and less than 1E-07/year for delta-LERF, representing a finding of very low safety significance (GREEN) for Unit 1 and Unit 2.
Cross-Cutting Aspect: P.2 - Evaluation: The organization thoroughly evaluates issues to ensure that resolutions address causes and extent of conditions commensurate with their safety significance. Although corrosion was identified in the FLEX 480V diesel generator radiator coolant in 2023 the licensee did not evaluate the cause(s) to take appropriate corrective actions to resolve the cause.
Enforcement:
Violation: 10 CFR 50.155(c)(1) requires, "the equipment relied on for the mitigation strategies and guidelines required by paragraph (b)(1) [Mitigation strategies for beyond-design basis external events] of this section must have sufficient capacity and capability to perform the functions required by paragraph (b)(1) of this section." Contrary to this requirement from the period of January 31,2024 to April 11, 2025, the licensee failed to have sufficient capability to perform functions required by paragraph (b)(1). Specifically, the B FLEX 480V diesel generator required by paragraph(b)(1) was incapable of performing Phase 2 AC power mitigation of beyond-design-basis event strategy for one of the two PSL units due to excessive corrosion causing failure to reject diesel heat to the atmosphere and overheating the unit.
Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Licensee-Identified Non-Cited Violation 71153 This violation of very low safety significance was identified by the licensee and has been entered into the licensee corrective action program and is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Violation: Saint Lucie Unit 1 technical specification (TS) limiting condition for operation (LCO)3.5.1 Condition B failure to meet SR 3.5.1.2 safety injection tank borated water volume. Surveillance requirement 3.5.1.2 requires safety injection tank borated water volume to be between 1090 ft3 and 1170 ft3.
Contrary to the above, following replacement of Unit 1 1A1 safety injection tank level indicator on January 27, 2025, the licensee identified the 1A1 safety injection tank borated water volume had been greater than 1170 ft3 (inoperable) from January 8, 2025, to January 27, 2025, and the required actions of TS LCO 3.5.1 Condition B, restore the safety injection tank to operable status, had not been completed within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
Significance/Severity: Green. The inspectors assessed the significance of the violation using IMC 0609 Appendix A, Mitigating SSCs and PRA Functionality (except Reactivity Control Systems). Specifically, the six mitigating SSC questions in IMC 0609 Appendix A, Exhibit 2.A were answered no.
Corrective Action References: AR 02506489, AR 02506437, AR
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On July 8, 2025, the inspectors presented the integrated inspection results to Mr. Carlos Santos, Site Vice President and other members of the licensee staff.
- On June 27, 2025, the inspectors presented the ISFSI inspection results to Mr. Paul Rasmus, General Manager and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
60854
Miscellaneous
HI-2114830
Final Safety Analysis Report on the HI-STORM FW MPC
Storage System
SYSTEM
Rev. 10
60856
Corrective Action
Documents
25 ISFSI Inspection - MPC Lid Cutting
60856
Corrective Action
Documents
25 ISFSI Inspection - Cask Tip Over Calc
Corrective Action
Documents
FLEX 480V D/G B Coolant Low PH and Corrosion Identified
09/28/2023
Procedures
ADM-09.22
Equipment Out Of Service
Rev. 35
Procedures
ADM-17.34
Diverse and Flexible Coping Strategies (FLEX) Program
Rev. 27
Procedures
FLEX-AA-100-
1006
FLEX 480V Diesel (TAD1353GE and TAW1643GE)
Rev. 4