IR 05000333/2025001
| ML25133A193 | |
| Person / Time | |
|---|---|
| Site: | FitzPatrick  |
| Issue date: | 05/13/2025 |
| From: | Jason Schussler Division of Operating Reactors |
| To: | Rhoades D Constellation Energy Generation, Constellation Nuclear |
| References | |
| IR 2025001 | |
| Download: ML25133A193 (1) | |
Text
May 13, 2025
SUBJECT:
JAMES A. FITZPATRICK NUCLEAR POWER PLANT - INTEGRATED INSPECTION REPORT 05000333/2025001
Dear David Rhoades:
On March 31, 2025, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at James A. FitzPatrick Nuclear Power Plant. On April 24, 2025, the NRC inspectors discussed the results of this inspection with Alex Sterio, 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.
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 I; the Director, Office of Enforcement; and the NRC Resident Inspector at James A. FitzPatrick Nuclear Power Plant.
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 I; and the NRC Resident Inspector at James A. FitzPatrick Nuclear Power Plant. 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, Jason E. Schussler, Chief Projects Branch 1 Division of Operating Reactor Safety
Docket No. 05000333 License No. DPR-59
Enclosure:
As stated
Inspection Report
Docket Number:
05000333
License Number:
Report Number:
Enterprise Identifier: I-2025-001-0051
Licensee:
Constellation Energy Generation, LLC
Facility:
James A. FitzPatrick Nuclear Power Plant
Location:
Oswego, NY
Inspection Dates:
January 1, 2025 to March 31, 2025
Inspectors:
E. Miller, Senior Resident Inspector
V. Fisher, Resident Inspector
D. Beacon, Senior Project Engineer
P. Cataldo, Senior Reactor Inspector
N. Floyd, Senior Reactor Inspector
K. Smetana, Reactor Engineer
A. Turilin, Reactor Inspector
Approved By:
Jason E. Schussler, Chief
Projects Branch 1
Division of Operating Reactor Safety
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at James A. FitzPatrick Nuclear Power Plant, 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
Failure to Address 'B' Emergency Service Water Degraded Pump Case Bolts Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000333/2025001-01 Open/Closed
[P.1] -
Identification 71152A The inspectors identified a Green finding and associated non-cited violation (NCV) of Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Appendix B, Criterion XVI, "Corrective Action," for Constellations failure to identify and correct a condition adverse to quality associated with degraded pump case bolts. Specifically, between 2018 and 2024,
Constellation staff failed to identify severely corroded bolts that provide structural connections between each vertical pump section of the B emergency service water (ESW) pump.
Overthrust of the Residual Heat Removal 'B' Low Pressure Coolant Injection Inboard Injection Valve Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000333/2025001-02 Open/Closed
[H.8] -
Procedure Adherence 71152A The inspectors identified a Green finding and associated NCV of 10 CFR Part 50, Appendix B,
Criterion V, "Instructions, Procedures, and Drawings," for failure to follow procedure during a planned maintenance activity associated with 10MOV-25B, residual heat removal (RHR) B low pressure coolant injection (LPCI) inboard injection valve. Specifically, while performing diagnostic testing,10MOV-25B was overthrust into its seat due to maintenance personnel failing to follow procedure.
Additional Tracking Items
None.
PLANT STATUS
FitzPatrick began the inspection period operating at rated thermal power and remained at, or near, rated thermal power for the 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
71111.01 - Adverse Weather Protection
Seasonal Extreme Weather Sample (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated readiness for seasonal extreme weather conditions prior to the onset of seasonal cold temperatures for the main intake, emergency service water (ESW) system, and residual heat removal (RHR) service water system on January 10, 2025.
Impending Severe Weather Sample (IP Section 03.02) (1 Sample)
- (1) The inspectors evaluated the adequacy of the overall preparations to protect risk-significant systems from impending lake effect snow and a cold weather advisory on January 21, 2025.
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)
'A' standby liquid control system on January 22, 2025
- (2) Control rod drive system on January 28, 2025
- (3) High pressure coolant injection (HPCI) system on January 29, 2025 (4)
'B' ESW system on January 30, 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) Battery room complex 272' and 282', fire areas/zones III/BR-1, IV/BR-2, BR-4, XVI/BR-5 on January 15, 2025
- (2) Cable spreading room 272', fire area/zone VII/CS-1 on January 15, 2025
- (3) Reactor building west 272', fire area/zone X/RB-1B on January 29, 2025
- (4) Pump rooms (screenwell) 255', fire areas/zones 12/SP-1, 13/SP-2 IB/FP-1 and FP-3 on February 12, 2025
- (5) East cable tunnel 258', fire area/zone II/CT-2 on February 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 March 20, 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 operations personnel during planned control rod exercising on March 15, 2025.
Licensed Operator Requalification Training/Examinations (IP Section 03.02) (1 Sample)
- (1) The inspectors observed a simulator scenario evaluation that included an anticipated transient without scram, a reactor coolant leak inside containment, and a failure of all reactor pressure vessel level instrumentation on February 4, 2025.
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) Elevated risk during 71INV-3A, 'A' 419 volt (V) direct current (DC) low pressure coolant injection (LPCI) motor-operated valve (MOV) independent power supply (IPS)unplanned maintenance following a voltage drop, on January 27, 2025
- (2) Emergent replacement of transducer card and capacitor on 'A' 419 V DC LPCI MOV IPS following a voltage drop on January 31, 2025
- (3) Emergent battery cell replacement on the 'A' 419 V DC LPCI MOV IPS following a voltage drop on February 9, 2025
- (5) Emergent replacement of 'C' EDG cylinder 10 fuel injector on March 12, 2025
- (6) Elevated risk during Line 4 planned maintenance on offsite power system on March 20, 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)
'B' safety relief valve due to lowering temperature trend on January 16, 2025
- (2) Operator burden associated with the main generator voltage regulator being taken from automatic to manual on January 27, 2025 (3)
'A' 419 V DC LPCI MOV IPS following a voltage drop on January 28, 2025 (4)71SB-1, 'A' 125 V DC station battery following discovery of battery cell 45 lid crack on February 6, 2025 (5)71BAT-3B, LPCI MOV IPS battery cell degradation on multiple cells on February 20, 2025
- (6) HPCI main pump inboard seal leak on March 3, 2025
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) (6 Samples)
- (1) Secondary containment administration building to reactor building fire and airlock door 24R-272-5 following door repair on January 22, 2025 (2)71INV-3A, 'A' 419 V DC LPCI MOV IPS following a capacitor and interface board replacement on January 31, 2025 (3)71BAT-3A, 'A' 419 V DC LPCI MOV IPS following jumper of a degraded battery cell and 71INV-3A inverter transducer card replacement on February 11, 2025 (4)71BAT-3B, 'B' 419 V DC LPCI MOV IPS following two degraded battery cell replacements on February 25, 2025
- (5) Carbon dioxide fire suppression system for the relay room following failure during functional testing on February 27, 2025 (6)
'C' EDG following replacement of a failed fuel injector on cylinder 10 on March 12, 2025
Surveillance Testing (IP Section 03.01) (3 Samples)
- (2) ST-3PB, Core Spray 'B' Quarterly Operability Test (IST), on March 6, 2025
Inservice Testing (IST) (IP Section 03.01) (2 Samples)
(1)29AOV-86B and 29AOV-86C main steam isolation valve following actuator replacement on February 28, 2025
Diverse and Flexible Coping Strategies (FLEX) Testing (IP Section 03.02) (1 Sample)
- (1) FLEX diesels FLEX-DG1 and FLEX-DG2 annual 30 percent loaded run on February 26, 2024
71114.06 - Drill Evaluation
Additional Drill and/or Training Evolution (1 Sample)
- (1) The inspectors observed and evaluated a simulator scenario that included an anticipated transient without scram, a reactor coolant leak inside containment, and a failure of all reactor pressure vessel level indication on February 4,
OTHER ACTIVITIES - BASELINE
===71151 - Performance Indicator Verification
The inspectors verified licensee performance indicators submittals listed below:
IE01: Unplanned Scrams per 7000 Critical Hours Sample (IP Section 02.01)===
- (1) For the period of January 1, 2024 through December 31, 2024
IE03: Unplanned Power Changes per 7000 Critical Hours Sample (IP Section 02.02) (1 Sample)
- (1) For the period of January 1, 2024 through December 31, 2024
IE04: Unplanned Scrams with Complications (USwC) Sample (IP Section 02.03) (1 Sample)
- (1) For the period of January 1, 2024 through December 31, 2024
===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) Issue Report (IR) 04800103 - 'B' Emergency Service Water Degraded Pump Case Bolts
- (2) IR 04800066 - Review of Corrective Actions Associated with Motor-Operated Valve Overthrust Events
71153 - Follow-up of Events and Notices of Enforcement Discretion Personnel Performance (IP Section 03.03)
- (1) The inspectors evaluated a voltage drop associated with 'A' 419 V DC LPCI MOV IPS battery supply, and the licensees performance, on February 11, 2025.
Notice of Enforcement Discretion (IP Section 03.04) (1 Sample)
- (1) The inspectors evaluated the licensee actions surrounding Notice of Enforcement Discretion (EA-24-113, ADAMS Accession No. ML24270A145), which can be accessed at https://www.nrc.gov/reading-rm/doc-collections/enforcement/notices/noedreactor.html, on March 18,
INSPECTION RESULTS
Failure to Address 'B' Emergency Service Water Degraded Pump Case Bolts Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems
Green NCV 05000333/2025001-01 Open/Closed
[P.1] -
Identification 71152A The inspectors identified a Green finding and associated non-cited violation (NCV) of Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Appendix B, Criterion XVI, "Corrective Action," for Constellations failure to identify and correct a condition adverse to quality associated with degraded pump case bolts. Specifically, between 2018 and 2024, Constellation staff failed to identify severely corroded bolts that provide structural connections between each vertical pump section of the B emergency service water (ESW) pump.
Description:
The ESW system is a two-train system, each providing 100 percent cooling requirements for all safety-related equipment in the corresponding system train, including the EDGs. Upon loss of normal service water, the ESW system supplies the safety-related crescent area coolers. There are five coolers in each train, providing area room cooling to the emergency core cooling system pumps during a design basis loss of coolant accident and loss of offsite power. Each pump is a cast iron, 2-stage, vertical turbine that takes suction from the intake, that is supplied by Lake Ontario and can produce up to 3,700 gallons per minute.
On September 8, 2024, during refuel and maintenance outage (RFO) diver intake cleaning, it was discovered that the B ESW pump case bolts were severely corroded. The pump contains 24 bolts that are submerged in lake water. When the diver touched several bolt heads, they eroded. The station determined that the bolts would need to be replaced prior to startup from the RFO. All bolts required destructive means to remove them.
The inspectors determined FitzPatrick had opportunities during the 2018, 2020 and 2022 RFOs to identify the degraded pump bolts. The station performs intake cleaning as part of an outage preventive maintenance (PM) activity, PM identification number 00339254. The inspectors found that the PM work orders did not specifically direct inspection of the ESW or other safety-related pumps in the area. However, diving coordinators directed inspections of the pumps verbally during cleaning.
In 2018, divers identified similar corrosion on the A and C RHR service water pumps, as documented in IR 04175529 and IR 04175532. These safety-related pumps are adjacent to the ESW pumps. The station replaced the bolts on each of the pumps. The station did not perform an extent of condition review. In 2020 and 2022 the station performed drone inspections, however degradation was not identified by Constellation staff.
Title 10 CFR Part 50 Appendix B Criterion XVI states in part, measures shall be established to assure that conditions adverse to quality, such as failures, malfunctions, deficiencies, deviations, defective material and equipment, and nonconformances are promptly identified and corrected. The inspectors observed the degraded bolts following removal. Given the condition, and the length of time since the pump was last replaced in 2000, the inspectors determined that Constellation failed to adequately identify and correct a condition adverse to quality between 2018 and 2022 associated with the B ESW pump case bolts degrading due to corrosion.
Corrective Actions: The degraded B ESW pump case bolts were all replaced. In addition, the station generated an action item to update the PM task to include pump case inspections during intake diving activities. The station performed a review of past operating history and determined flow rates were adequately achieved during the previous two years.
Corrective Action References: IR 04800103
Performance Assessment:
Performance Deficiency: The inspectors determined that Constellation failed to perform adequate inspections to identify and correct a condition adverse to quality associated with degraded ESW pump case bolts between 2018 and 2022 in accordance with 10 CFR Part 50, Appendix B, Criterion XVI, Corrective Action.
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. This issue is also similar to IMC 0612, Appendix E, Example 3.e, in that the resulting condition was unacceptable and the bolts were replaced. Specifically, the station failed to perform adequate inspections of the B ESW pump between 2018 and 2022, as a result, degraded bolts were not identified until the 2024 RFO diving inspections.
Significance: The inspectors assessed the significance of the finding using IMC 0609, Appendix A, The Significance Determination Process (SDP) for Findings At-Power. The inspectors determined this finding to be of very low safety significance (Green) in accordance with Exhibit 2, because it involved a deficiency affecting the design or qualification of a mitigating structures, systems and components (SSCs) that did not affect its operability or probabilistic risk assessment functionality.
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, Constellation staff did not identify during diving and drone inspections degradation of the B ESW pump case bolts.
Enforcement:
Violation: Title 10 CFR Part 50, Appendix B, Criterion XVI, "Corrective Action," states measures shall be established to assure that conditions adverse to quality, such as failures, malfunctions, deficiencies, deviations, defective material and equipment, and nonconformances are promptly identified and corrected.
Contrary to the above, between September 2018 and October 2022, Constellation failed to adequately perform inspections to ensure that B ESW pump components remained reliable.
Specifically, diving activities failed to identify degraded pump case bolts associated with the B ESW pump, which required immediate replacement.
Enforcement Action: This violation is being treated as an NCV, consistent with Section 2.3.2 of the Enforcement Policy.
Overthrust of the Residual Heat Removal 'B' Low Pressure Coolant Injection Inboard Injection Valve Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems
Green NCV 05000333/2025001-02 Open/Closed
[H.8] -
Procedure Adherence 71152A The inspectors identified a Green finding and associated NCV of 10 CFR Part 50, Appendix B, Criterion V, "Instructions, Procedures, and Drawings," for failure to follow procedure during a planned maintenance activity associated with 10MOV-25B, residual heat removal (RHR) B low pressure coolant injection (LPCI) inboard injection valve. Specifically, while performing diagnostic testing,10MOV-25B was overthrust into its seat due to maintenance personnel failing to follow procedure.
Description:
There are two RHR systems at FitzPatrick. Each RHR system includes two pumps that will receive signals to automatically start during a loss of coolant accident such as high drywell (containment) pressure signal or if there is low reactor pressure vessel (RPV)water level signal. The pumps provide coolant to the RPV once pressure has lowered to allow the LPCI valve, 10MOV-25A, to open. The two valves, 10MOV-25A and 10MOV-25B, can be manually opened and closed by the operators in the main control room during implementation of emergency operating procedures and they are both credited as primary containment isolation valves.
On September 8, 2024, during the refueling outage, FitzPatrick maintenance personnel performed several maintenance activities associated with 10MOV-25B. Maintenance activities included a wiring change to control valve closure, diagnostic testing, and inspection.
Procedure MA-AA-723-300, "Diagnostic Testing of Motor Operated Valves," Revision 14, Step 4.6.4, directs performers to Disable the extended close torque switch bypass limit switch contact, IF installed. Record on Attachment 6. Contrary to procedure HU-AA-104-101, "Procedure Use and Adherence," the personnel performing MA-AA-723-300, Step 4.6.4, failed to perform placekeeping and missed this step. As a result, the valve was overthrust into its seat until the motor stalled. This required extensive inspection and engineering evaluation to determine the viability of the valve to meet its design function prior to restoration.
Procedure HU-AA-104-101, Procedure Use and Adherence, Revision 8, Step 4.4.3 and Step 4.4.4, requires "placekeeping" to be performed for all steps, sub-steps, and actions, including list bullets, precautions, prerequisites, and limitation when sections of Level 2 - Reference Use procedures that manipulate "positionable" components. Contrary to the requirements of HU-AA-104-101, Constellation staff failed to perform a step during performance of MA-AA-723-300.
Corrective Actions: Constellation performed a standdown with supplemental valve maintenance staff, who inspected the actuator for thrust damage, replaced house cover fasteners, replaced breaker thermal overloads, inspected the valve yoke and performed an engineering weak link analysis.
Corrective Action References: IR 04800066
Performance Assessment:
Performance Deficiency: The failure to follow procedure MA-AA-723-300 during diagnostic testing was reasonably within Constellation staff's ability to foresee and prevent. Specifically, the failure to perform a step resulted in an overthrust of the valve disc into its seat that required extensive follow-up evaluation.
Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Human 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. This issue is also similar to IMC 0612, Appendix E, Example 3.e, in that the resulting condition was unacceptable and additional inspections were performed such as magnetic particle examination of the valve yoke, inspection of the motor, stem nut replacement and an engineering weak link analysis. Specifically, while performing as left diagnostic testing on 10MOV-25B, a step was not performed resulting in overthrust of the valve disc into its seat, resulting in additional actions by the station to address a condition adverse to quality.
Significance: The inspectors assessed the significance of the finding using IMC 0609, Appendix A, The Significance Determination Process (SDP) for Findings At-Power. The inspectors determined this finding to be of very low safety significance (Green) in accordance with Exhibit 2, because it
- (1) did not involve a deficiency affecting the design or qualification of a mitigating SSC that affected its operability or probabilistic risk assessment (PRA)functionality;
- (2) was not a degraded condition that represented a loss of the PRA function of a single train technical specification (TS) system for greater than its TS allowed outage time;
- (3) did not represent a loss of the PRA function of one train of a multi-train TS system for greater than its TS allowed outage time;
- (4) did not represent a loss of the PRA function of two separate TS systems for greater than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />;
- (5) did not represent a loss of a PRA system and/or function as defined in the Plant Risk Information Book or the licensees PRA for greater than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />; and
- (6) did not represent a loss of the PRA function of one or more non-TS trains of equipment designated as risk-significant in accordance with the licensees maintenance rule program for greater than three days.
Cross-Cutting Aspect: H.8 - Procedure Adherence: Individuals follow processes, procedures, and work instructions. Specifically, Constellation did not follow procedure while performing as left diagnostic testing on 10MOV-25B and as a result the valve overthrust into its seat.
Enforcement:
Violation: Title 10 CFR Part 50, Appendix B, Criterion V, " Instructions, Procedures, and Drawings," requires, in part, that activities affecting quality shall be prescribed by documented instructions, procedures, or drawings, of a type appropriate to the circumstances and shall be accomplished in accordance with these instructions, procedures, or drawings.
Contrary to the requirements of 10 CFR Part 50, Appendix B, Criterion V, Constellation failed to perform procedure MA-AA-723-300 in accordance with the written instructions in the procedure. Specifically, Constellation failed to follow procedure use and adherence requirements prescribed in HU-AA-104-101 regarding placekeeping and therefore missed Step 4.6.4 in MA-AA-723-300, resulting in overthrust of the LCPI injection valve 10MOV-25B.
Enforcement Action: This violation is being treated as an NCV, consistent with Section 2.3.2 of the Enforcement Policy.
Minor Performance Deficiency 71152A Review of Corrective Actions Associated with Motor-Operated Valve Overthrust Events
Minor Performance Deficiency: In the second quarter of 2023, the inspectors documented an observation in NRC Inspection Report 05000333/2023002 (ML23219A114) associated with safety-related motor-operated valve performance issues identified during the 2022 fall refuel and maintenance outage. Of note, events included the hammering of the 29MOV-74, main steam line drain isolation valve, IR 04527898; and 10MOV-25A, the A LPCI inboard containment isolation valve, IR 04526683. The station performed a work group evaluation associated with the 10MOV-25A failure.
On September 8, 2024, the station experienced an overthrust event associated with the 10MOV-25B, the B LPCI inboard containment isolation valve, IR 04800066.
The inspectors performed a review of Constellations screening, evaluation, and corrective actions associated with the events in 2022 and 2024 to determine if they were related and whether the corrective actions were effective.
The LPCI injection valves have a safety-related function to open and close to ensure coolant can be provided to the RPV following a design basis event. The 10MOV-25A and 10MOV-25B valves are 24-inch model SMB-4. These valves are a unique design in that their gear train, which supplies the motive force to move the valve stem and disc, can relax causing the forces that drive the valve closed or open to reduce in force. The design includes two means to stop the valve. The primary method is to sense the torque using a torque switch which then stops the flow of electricity to the motor upon reaching the limit setting. The relaxation of the gear train causes the torque switch to reset. If provided a continuous signal from the control room hand switch, the valve will re-attempt to close until the torque switch trips again. This can happen as much as five times per second. This repeated event is termed hammering.
As part of the inspection documented in NRC Inspection Report 05000333/2023002, the inspectors identified a hammering event that occurred in 2018. Constellation documented this issue in IR 04542603. The station screened the significance as Level 4 and Class D, the lowest level of significance, and assigned an action item to review the event. Constellations review confirmed a hammering event occurred and that the valve was susceptible to similar failure in the future. The station did not take any additional actions to ensure similar events would be prevented. The inspectors determined that the station did not adequately address the condition described in this IR, resulting in continued vulnerability for this issue to occur again.
In addition, IR 04526683 from 2022 was screened for priority as Significance Level 4 and Class D. The inspectors determined that Constellation did not properly classify the event as Significance Level 3. Specifically, Constellation procedure PI-AA-120, Issue Identification and Screening Process, Revision 14, Attachment 2 provides example yy under Significance Level 3 Guidance - Asset Management-Equipment Reliability, which states, degraded condition or non-conformance affecting the safety-related function of a structure, system, or component. The inspectors determined the degraded/non-conforming condition was consistent with the example and should have been screened as Significance Level 3.
Issue Report 04800066 from 2024 was also screened for priority as Significance Level 4 and Class D. The inspectors determined that Constellation did not properly classify the event as Significance Level 3. Specifically, Constellation procedure PI-AA-120, Issue Identification and Screening Process, Revision 14, Attachment 2 provides example r under Significance Level 3 Guidance - Operational Execution-Fundamentals, which states Failure to follow a Level 2 or 3 procedure that results in undesirable consequences. The inspectors determined that given a maintenance staff member failed to follow a procedure, this IR was not properly classified.
Finally, IR 04526683 did not assign a corrective action (CA) to address the condition adverse to quality as required by PI-AA-125, Corrective Action Program (CAP) Procedure, Step 4.5.2., which states, in part:
Create a Corrective Action (CA)... for any planned action necessary to restore a condition adverse to quality (CAQ). The following guidance should be used to determine if the action is a CA (reference Attachment 1 for additional guidance and examples):
1. Actions that correct a Significance Level 1, 2 or 3 Condition.
2. Actions that correct adverse conditions with a System, Structure, or Component.
Contrary to the procedure step, a CA was not assigned to address the adverse condition of hammering to 10MOV-25A and other valves susceptible to hammering. Action item 3 of IR 04526683 to establish an anti-hammering modification was closed and directed to Work Order 05424360, which was placed on engineering hold due to a part obsolescence issue.
Issue Report 04790272 was written to document it; however, this IR was closed with no further action taken. As a result of the inspectors follow up, the station generated IR 04860293 to restore actions to address the obsolete part.
Title 10 CFR Part 50, Appendix B, Criterion XVI, states, "Measures shall be established to assure that conditions adverse to quality, such as failures, malfunctions, deficiencies, deviations, defective material and equipment, and nonconformances are promptly identified and corrected." Contrary to this requirement, Constellation has not properly screened and implemented corrective actions to address the condition adverse to quality associated with motor-operated valve hammering of designs with a susceptible gear train when control room switches are held after the valve reaches a closed position.
Screening: The inspectors determined the performance deficiency was minor. The inspectors determined that Constellations failure to address the condition adverse to quality associated with hammering was minor because while susceptibility to valve hammering has continued to exist, there has not been a subsequent hammering occurrence.
Observation: Emergency Service Water Pump Bolt Degradation Operability Evaluation 71152A The inspectors assessed the effectiveness of the licensees evaluation and corrective actions to address degraded bolting on the B ESW pump 46P-2B as described in IR 04818293.
Specifically, the inspectors reviewed Constellations evaluation to determine if the system would remain operable during a worst-case design basis seismic event. The subject bolts connect two impeller bowls and the end piece, consisting of three separate connections with eight bolts in each connection.
The inspectors assessed the licensee operability evaluation (ECR 0000465429) and determined that it did not contain specific information for independent conclusion regarding the bolt structural capabilities. Specifically, the inspectors noted that Constellation performed a calculation of stress analysis for the degraded bolting and assumed it to be degraded by 50 percent. However, the inspectors noted Constellation did not take any measurements to quantify the amount of actual bolt degradation. In addition, there was no supporting evidence in the determination of assumptions used in the calculation for the degraded bolts. Further, the stress analysis in the calculation utilized a four-bolt pattern spaced equally apart and equally among the three separate elevations, even though Constellation did not document the specific locations of the degraded bolts during disassembly. The inspectors independently observed the degraded bolts and noted that the heads on some of the bolts were mostly absent. The bolt head is a critical dimension as it holds the parts together. The inspectors independently verified the stress calculations using conservative assumptions to assess structural integrity and determined that there is reasonable assurance the structures would withstand a design basis seismic event. The inspectors verified corrective actions were completed to replace the degraded bolts utilizing bolts with a corrosion inhibiting coating. The inspectors did identify a performance deficiency of more than minor significance, which is discussed in this report.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On April 24, 2025, the inspectors presented the integrated inspection results to Alex Sterio, Site Vice President, and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Procedures
Intake Water Level Trouble
LPCI Independent Power Supply System
Battery Room Ventilation
OP-AA-108-111-
1001
Severe Weather and Natural Disaster Guidelines
OP-JF-102-102-
1001
Guidance for Augmented Rounds at JAF
WC-JF-107-1000
Seasonal Readiness T&RM for JAF
Drawings
Flow Diagram Standby Liquid Control System 11
Flow Diagram High Pressure Coolant Injection System 23
Flow Diagram Control Rod Drive System 03
Flow Diagram Emergency Service Water System 46 and 15
Procedures
High Pressure Coolant Injection
Standby Liquid Control System
Emergency Service Water (ESW)
Control Rod Drive Hydraulic System
Fire Plans
East Cable Tunnel Elev. 258' Fire Area/Zone II/CT-2
West Cable Tunnel Elev. 258' Fire Area/Zone IC/CT-1
Battery Room Complex Elev. 272', 282' Fire Area Zone
III/BR-1, IV/BR-2, BR-4, XVI/BR-5
Cable Spreading Room Elev. 272' Fire Area/Zone VII/CS-1
Reactor Building-West Elev. 272' Fire Area/Zone X/RB-1B
Reactor Building Elev. 369' Fire Area/Zone IX/RB-1A
Pump Rooms (Screenwell) Elev. 255' Fire Area/Zone 12/SP-
1, 13/SP-2 IB/FP-1 & FP-3
Procedures
Fire Drill Performance
71111.11Q Procedures
Control Rod Operability for Partially Withdrawn Control Rods
Control Rod Operability for Fully Withdrawn Control Rods
Corrective Action
Documents
04832611
04835886
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
04844022
Corrective Action
Documents
04382611
04830092
04833244
04834963
04838725
04842145
Procedures
Main Generator, Transformers and Isolated Bus Phase
Cooling
Operator Work-Around Program
Work Orders
05620521
Corrective Action
Documents
04831407
04840773
04844022
Procedures
Motor-Operated Valve Maintenance and Testing Guidelines
Air Operated Valve Categorization
Air Operated Valve Testing Requirements
Post Maintenance Testing
SEP-IST-007
Inservice Testing (IST) Program Plan
29
RCIC Flow Rate and Inservice Test (IST)
058
Core Spray Loop 'B' Class 2 Piping Leakage Test (ISI)
Core Spray 'B' Quarterly Operability Test (IST)
HPCI Quick-Start, Inservice, and Transient Monitoring Test
(IST)
085
Carbon Dioxide Simulated Automatic/Manual Initiation -
Relay Room
004
EDG A and C Full Load and ESW Pump Operability Test
EDG System Quick-Start Operability Test and Offsite Circuit
Verification
Work Orders
211130
294726
05312802
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
05322361
05388383
05388383
05524402
05604524
05620521
05620521
05626419
05631749
71151
Corrective Action
Documents
04793211
04803930
Corrective Action
Documents
04525932
04527898
04527980
04800066
04800612
04801928
Procedures
Issue Identification and Screening Process
Corrective Action Program Procedure
Corrective Action Program Evaluation Manual
Corrective Action
Documents
04802610
04803930
04803957
04804251
04835886
Procedures
LPCI 71BAT-3A Battery Monthly Surveillance Test
001
LPCI Battery Quarterly Surveillance Test
25