IR 05000440/2024001
| ML24113A141 | |
| Person / Time | |
|---|---|
| Site: | Perry  |
| Issue date: | 04/24/2024 |
| From: | Billy Dickson NRC/RGN-III/DORS/RPB2 |
| To: | Penfield R Vistra Operations Company |
| References | |
| EA-23-150 IR 2024001 | |
| Download: ML24113A141 (1) | |
Text
SUBJECT:
PERRY NUCLEAR POWER PLANT - INTEGRATED INSPECTION REPORT 05000440/2024001
Dear Rod Penfield:
On March 31, 2024, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Perry Nuclear Power Plant. On April 17, 2024, the NRC inspectors discussed the results of this inspection with you and other members of your staff. The results of this inspection are documented in the enclosed report.
One finding of very low safety significance (Green) is documented in this report. This finding involved a violation of NRC requirements. We are treating this violation as a non-cited violation (NCV) consistent with Section 2.3.2 of the Enforcement Policy.
If you contest the violation or the significance or severity of the violation 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 III; the Director, Office of Enforcement; and the NRC Resident Inspector at Perry 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 III; and the NRC Resident Inspector at Perry Nuclear Power Plant.
April 24, 2024 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, Billy C. Dickson, Jr., Chief Reactor Projects Branch 2 Division of Operating Reactor Safety Docket No. 05000440 License No. NPF-58
Enclosure:
As stated
Inspection Report
Docket Number:
05000440
License Number:
Report Number:
Enterprise Identifier:
I-2024-001-0076
Licensee:
Vistra Operations Company, LLC
Facility:
Perry Nuclear Power Plant
Location:
Perry, OH
Inspection Dates:
January 01, 2024 to March 31, 2024
Inspectors:
J. Beavers, Senior Resident Inspector
T. Ospino, Resident Inspector
Approved By:
Billy C. Dickson, Jr., Chief
Reactor Projects Branch 2
Division of Operating Reactor Safety
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at Perry 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
LER 2023-003-00 for Perry Nuclear Power Plant, Plant Trip During Reactor Protection System Power Transfer Cornerstone Significance Cross-Cutting Aspect Report Section Initiating Events Green NCV 05000440/2024001-01 Open/Closed EA-23-150
[H.12] - Avoid Complacency 71153 A self-revealed Green finding and an associated Non-Cited Violation (NCV) of Technical Specifications (T.S) 5.4.1was identified on August 10, 2023, when the licensee failed to position the power transfer switch in a slow and steady motion as to prevent over travel as written in Standard Operating Instruction SOI-C71, RPS Power Supply Distribution.
Specifically, the licensee inadvertently over traveled the reactor protection power transfer switch, which interrupted power to both reactor protection system busses. A reactor SCRAM resulted due to a temporary loss of power to both trains of reactor protection system power.
Additional Tracking Items
Type Issue Number Title Report Section Status LER 05000440/2023-003-00 LER 2023-003-00 for Perry Nuclear Power Plant, Plant Trip During Reactor Protection System Power Transfer 71153 Closed
PLANT STATUS
Unit 1 began the inspection period at rated thermal power and remained at or near rated thermal power. On January 24, 2024, the unit was automatically down powered to 75 percent due to a trip of a reactor feed pump. The unit was returned to rated thermal power on January 27, 2024, and remained at or near rated thermal power for the remainder of 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
71111.04 - Equipment Alignment
Partial Walkdown Sample (IP Section 03.01) (1 Sample)
The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:
(1)reactor core isolation cooling system on February 14, 2024
71111.05 - Fire Protection
Fire Area Walkdown and Inspection Sample (IP Section 03.01) (10 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 1ST, associated with steam tunnel, on January 5, 2024 (2)fire zone HB-620, associated with the heater bay, on January 9, 2024 (3)fire zones 1CC-3a, 1CC-3b, 1CC-3c, 1CC-3d, 2CC-3a, 2CC-3b, 2CC-3c, 2CC-3d, associated with control complex, on February 5, 2024 (4)fire zones 1CC-4a, 1CC-4c, 1CC-4d, 1CC-4g, 1CC-4h, associated with control complex, on February 5, 2024 (5)fire zones 2CC-4a, 2CC-4c, 2CC-4d, 2CC-4g, 2CC-4h, associated with control complex, on February 5, 2024 (6)fire zones 1RB-1B, associated with containment, on February 7, 2024 (7)fire zones RW-574, RW-602, RW-673, RW-646, associated with radwaste building, on February 8, 2024 (8)fire zone 1AB-1C, associated with the auxiliary building, on February 14, 2024 (9)fire zone OCC-2CC-4f 654' cable chase, on February 26 2024 (10)fire zone TP-647, associated with turbine building, on March 28, 2024
Fire Brigade Drill Performance Sample (IP Section 03.02) (1 Sample)
(1)the inspectors evaluated the fire brigade drill on February 21, 2024
71111.06 - Flood Protection Measures
Flooding Sample (IP Section 03.01) (1 Sample)
(1)the inspectors evaluated external flooding mitigation protections in the division-3 electrical safety-related manholes #1 and #2 the week of January 9, 2024
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 restoration of 'B' reactor feed pump to service and feedwater manipulations on January 26, 2024
Licensed Operator Requalification Training/Examinations (IP Section 03.02) (1 Sample)
(1)the inspectors observed and evaluated an evaluated simulator scenario on January 29, 2024
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)unit 2 plant vent isokinetic failure on January 15, 2024 (2)work planning and execution of activities related to the residual heat removal 'B'/'C' waterleg pump work between February 19 and March 30, 2024
71111.13 - Maintenance Risk Assessments and Emergent Work Control
Risk Assessment and Management Sample (IP Section 03.01) (5 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)emergent activities associated with the unplanned ONI-C11-1 entry, Inability to move Control rods and the potential consequences on December 31, 2023 (2)reactor core isolation cooling system outage, work order 200847842 (3)issues with the unit 1 plant isokinetic sample pump between February 26 and 27, 2024 (4)risk evaluation to the activities related to the division 2 emergency core cooling systems planned outage between February 19 and 23, 2024 (5)risk evaluation review of activities related to the residual heat removal 'B'/'C' waterleg pump work between February 19 and March 30, 2024
71111.15 - Operability Determinations and Functionality Assessments
Operability Determination or Functionality Assessment (IP Section 03.01) (5 Samples)
The inspectors evaluated the licensee's justifications and actions associated with the following operability determinations and functionality assessments:
(1)operability review after the failure of a power supply in the division 1 emergency diesel generator triggered multiple unplanned alarms on January 21, 2024 (2)functionality review of the division 2 diesel generator 1B starting air compressor after maintenance work between December 27 and 28, 2023 (3)functionality review of the main turbine electro hydrologic oil temperature controller between February 2 and 12, 2024 (4)operability review of the division 2 diesel generator lube oil strainer high differential pressure on January 19, 2024 (5)operability review of the average power range monitoring system after channels C and G were inoperable between March 3 to 4, 2024
71111.18 - Plant Modifications
Temporary Modifications and/or Permanent Modifications (IP Section 03.01 and/or 03.02)
(1 Sample 1 Partial)
The inspectors evaluated the following temporary or permanent modifications:
(1)permanent modification implementation of the dewatering system in the electrical manhole #1 (2)
(Partial)permanent modification implementation of procedural allowance for use of alternate keepfill regarding residual heat removal system
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) (10 Samples)
(1)replacement of the SEL-2411 relay as part of the startup transformer 200-PY system between July and December 14, 2023 (2)replacement of the control rod drive hydraulic power unit 'B' filter SL-1 on December 21, 2023 (3)repair of reactor core isolation cooling pump flow controller on January 22, 2024 (4)repair of 'B' oscillating power range monitor on January 23, 2024 (5)installation, assembling, and disassembling of the division 1 diesel generator left turbo in November 2023 (6)repair of reactor water clean-up flange on 'A' regenerative heat exchanger on December 11, 2023 (7)replacement of 'F' average power range monitor flow card NESC0771-003 on October 18, 2023 (8)recovering of the Unit #2 plant ventilation monitor to include the sample pump replacement between January 15 and 30 2024 (9)replacement of the EHC fluid temperature control valve controller P44-R347 on February 6, 2024 (10)replacement of relay in MCC bucket EF1D09 on January 4, 2024
Surveillance Testing (IP Section 03.01) (5 Samples)
(1)turbine valve operability test surveillance performed on January 6, 2024 (2)main turbine and generator surveillance on January 6, 2024 (3)
'A' standby liquid control surveillance on December 20, 2023 (4)high pressure core spray surveillance on January 30, 2024 (5)
'B' emergency service water surveillance on January 23, 2024
Inservice Testing (IST) (IP Section 03.01) (1 Sample)
(1)replacement and testing of relieve the valve with serial number #50 to #55 between November 2023 and February 20, 2024
Diverse and Flexible Coping Strategies (FLEX) Testing (IP Section 03.02) (1 Sample)
(1)review of the 4160v FLEX generators quarterly test on February 7, 2024
71114.06 - Drill Evaluation
Required Emergency Preparedness Drill (1 Sample)
(1)crew evaluation for an emergency response evaluation on February 5,
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) Unit 1 (January 1, 2023 through December 31, 2023)
IE03: Unplanned Power Changes per 7000 Critical Hours Sample (IP Section 02.02) (1 Sample)
- (1) Unit 1 (January 1, 2023 through December 31, 2023)
IE04: Unplanned Scrams with Complications (USwC) Sample (IP Section 02.03) (1 Sample)
- (1) Unit 1 (January 1, 2023 through December 31, 2023)
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)
'B'/'C' residual heat removal water leg pump leakage
===71152S - Semiannual Trend Problem Identification and Resolution Semiannual Trend Review (Section 03.02) (1 Partial)
(1)
(Partial)
The inspectors reviewed the licensees corrective action program to identify potential trends in work planning and execution Issues that might be indicative of a more significant safety issue.
71153 - Follow-Up of Events and Notices of Enforcement Discretion Event Follow-up (IP Section 03.01)===
(1)the inspectors evaluated NRC Event Notification 56914, notification of environmental report to another government agency and licensees response on January 5, 2024.
(2)the inspectors evaluated 'B' reactor feed pump trip and automatic flow control valve runback from 100% power to 75% power on January 24, 2024.
Event Report (IP Section 03.02) (1 Sample)
The inspectors evaluated the following licensee event reports (LERs):
- (1) LER 05000440/2023-003-00, (ADAMS Accession No. ML23271A026). The inspection conclusions associated with this LER are documented in this report under Inspection Results Section 71153. This LER is Closed.
INSPECTION RESULTS
Observation: 'B'/'C' Residual Heat Removal Water Leg Pump Leakage 71152A The inspectors evaluated the corrective action maintenance on the 'B'/'C' residual heat removal systems' water leg pump, including maintenance work planning and execution during the initial effort in February and the rework in March of 2024. The inspectors selected this sample due to the impact of the component on the residual heat removal systems mitigating systems 'B' and 'C' and the containment function impact on the feedwater leakage control system. During the rework effort, the licensee identified a component installation issue that was the source of the excess leakage following the February pump replacement. The inspectors evaluated this issue using the attributes discussed in NUREG-2165, "Safety Culture Common Language." The inspectors characterized this performance deficiency under the work process behavior trait and specifically the work management (WP.1) attribute, where the organization implements a process of planning, controlling, and executing work activities such that nuclear safety is the overriding priority. The work process includes the identification and management of risk commensurate to the work. The inspectors determined that the significance of this issue was minor in nature, as the overall safety function was maintained during both corrective action work windows. It is worth noting that the second work window was an extra exposure to risk regarding this safety-related equipment and disrupted the standard workweek schedule. The inspectors identified no more than minor findings or violations.
LER 2023-003-00 for Perry Nuclear Power Plant, Plant Trip During Reactor Protection System Power Transfer Cornerstone Significance Cross-Cutting Aspect Report Section Initiating Events Green NCV 05000440/2024001-01 Open/Closed EA-23-150
[H.12] - Avoid Complacency 71153 A self-revealed Green finding and an associated Non-Cited Violation (NCV) of Technical Specifications (T.S) 5.4.1was identified on August 10, 2023, when the licensee failed to position the power transfer switch in a slow and steady motion as to prevent over travel as written in Standard Operating Instruction SOI-C71, RPS Power Supply Distribution. Specifically, the licensee inadvertently over traveled the reactor protection power transfer switch, which interrupted power to both reactor protection system busses. A reactor SCRAM resulted due to a temporary loss of power to both trains of reactor protection system power.
Description:
On August 10, 2023, with the plant operating in Mode 1 and approximately 100 percent power, a Group 1 Main Steam Isolation Valves (MSIVs) primary containment isolation and automatic reactor scram occurred during the transfer of the Reactor Protection System (RPS)
B power supply from the alternate power supply to the normal power supply when both trains of the RPS power distribution were inadvertently de-energized. The NRC resident inspector office staff were immediately notified and responded to the event.
When transferring RPS power from the alternate supply to the normal supply, the power transfer switch uses a break-before-make contact, which creates a temporary loss of power to the respective RPS bus for which power is being transferred. If the switch is over-traveled, then RPS buses can lose power for a brief period. Therefore, the licensee has procedural instructions to move this switch in a slow and steady motion to avoid this condition. However, when transferring the RPS train B power supply from the alternate back to normal, the switch was inadvertently over-traveled, and a reactor scram occurred since both RPS busses briefly lost power. The RPS busses also power the isolation circuitry for the Group 1 isolation such that a loss of power to the circuitry initiates a Group 1 isolation. Therefore, when the reactor SCRAM occurred, a Group 1 isolation additionally caused the MSIVs to close. Following the SCRAM and closure of the MSIVs, plant equipment and personnel responded as required and expected.
All rods inserted on the scram shutting down the reactor. All system actuations and isolation occurred as required, noting that RPS B (outboard) primary containment valves were initially de-energized during the original transfer of RPS B supply power and, therefore, remained de-energized and open during the power loss; all inboard RPS A valves automatically isolated during the transient loss of RPS. Apart from the operation of the power transfer switch, all equipment and personnel responded as required and expected.
To perform a transfer from the B alternate transformer to the normal B MG set, the RPS power transfer switch is rotated from the 45-degree position (ALT B) to the 0-degree position (NORM). Similarly, to transfer the RPS bus A power supply from the normal A MG set to the A alternate transformer, the power transfer switch is rotated from 0-degree (NORM) to the 315-degree position (ALT-A). The operating procedure contains caution: Movement of the MG SET TRANSFER switch 1C71-S1 shall be performed in a slow and steady motion. When placing it in NORM, 3 to 5 degrees of over-travel may cause loss of RPS bus A. The licensee added this caution statement due to a similar incident that occurred in 1988. The control room operator was transferring the RPS B power supply from the alternate feed transformer to the normal B motor-generator set, per the operating procedure, following restoration from RPS breaker maintenance. The transfer of RPS power is a non-paralleling break before make transfer, causing the RPS busloads to be momentarily de-energized. The licensee expected a Division 2 half-scram during the transfer. However, an unexpected break in power to the RPS A bus also occurred, providing the second half-scram signal and a full RPS actuation and reactor scram. Plant operators restated the reactor on August 15, 2023.
The direct cause of the scram was attributed to inadvertent overtravel of the RPS power transfer switch, resulting in a second switch contact associated with RPS A opening, causing the automatic scram. The root cause of the scram was failing to implement a higher-level safety precedence sequence corrective action, such as a design change implementation, to prevent the recurrence of a plant scram due to a known design vulnerability.
The inspectors determined that the failure to perform movement of the RPS transfer switch in a slow and steady motion was a performance deficiency. Had the licensee moved the switch as stated in the procedure, both RPS buses would not have been de-energized, and the plant would not have been challenged with a reactor SCRAM.
A licensee Probabilistic Risk Assessment (PRA) bounding evaluation was performed for the August 10, 2023, automatic scram with loss of condenser. An analysis of this complicated plant scram resulted in a delta Core Damage Frequency (CDF) and a delta Large Early Release Frequency (LERF) that are well below the acceptable thresholds of 1.0E-06/yr and 1.0E-07/yr, respectively, as discussed in Regulatory Guide 1.1.74.
Therefore, in accordance with the regulatory guidance, the risk of this event was considered to be of very low safety significance.
Regarding NEI 99-07, revision 7, Regulatory Assessment Performance Indicator Guideline, this scram has been determined to be an unplanned scram with complications. This event is reportable due to the actuation of RPS, including a reactor scram, isolation of the MSIVs, and the actuation of Emergency Core Cooling Systems (ECCS) under 10 CFR 50.73(a)(2)(iv)(A).
Corrective Actions:
The licensee placed the RPS Power Transfer Switch with a like-for-like switch as an immediate corrective action, and a planned corrective action is to upgrade the switch to remove the known design vulnerability. The RPS power transfer switch design will be upgraded during the next scheduled refueling outage in Spring 2025 to prevent a similar event from occurring again.
Corrective Action References: CR-2023-06215, Automatic Reactor SCRAM and MSIV Closure Following RPS Bus Shift from ALT to NORM B
Performance Assessment:
Performance Deficiency: Procedure SOI-C-71, Steps 7.2.31 and 7.3.28, state, "Movement of MG SET TRANSFER switch 1C71-S1, shall be performed in a slow and steady motion. When placing it in NORM, 3 to 5 degrees of over-travel may cause loss of RPS bus." The licensee failed to follow Procedure SOI-C-71 and inadvertently over traveled the RPS power transfer switch while selecting the normal source of power. This failure caused both RPS busses to lose power temporarily, which subsequently caused a reactor SCRAM Signal. Therefore, the failure to follow operating instructions was a performance deficiency.
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. The inspectors compared the issue to the examples and guidance in IMC 0612, Appendix E, Examples of Minor Issues. Specifically, the error caused a reactor SCRAM. The issue is similar to Inspection Manual Chapter (IMC) 0612, Appendix E, Examples of Minor Issues, example 4.b.
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 assessed the significance of the finding using IMC 0609, Appendix A, The Significance Determination Process for Findings At-Power. The inspectors screened the finding using Exhibit 1, Initiating Events Screening Questions, Section B, Transient Initiators.
The inspectors answered yes to the question, which results in performing a detailed risk evaluation.
A Region III senior reactor analyst (SRA) performed a detailed risk evaluation to assess the significance of the finding. The finding resulted in both trains of RPS being inadvertently de-energized which led to a plant SCRAM. The issue was modeled as an initiating event with a loss of condenser heat sink (LOCHS).
In accordance with the Risk Assessment of Operational Events Handbook guidance, for findings that cause initiating events to occur, the initiating event that was observed is set to 1.0 or True and the conditional core damage probability is calculated. The conditional core damage probability is multiplied by one inverse year (yr-1) to equate this to a change in core damage frequency for the performance deficiency. For this finding, the initiating event Loss of Condenser Heat Sink was set to 1.0 using the events and condition assessment module of the Systems Analysis Program for Hands-On Integrated Reliability Evaluations (SAPHIRE),
Version 8.2.8.
The change in core damage frequency (CDF) due to internal events was estimated to be less than 1E-6/year, which represents a finding of very low safety significance (Green). The dominant core damage sequence for internal events involved failures of suppression pool cooling, containment spray, loss of ultimate heat sink, containment venting, and late injection.
The change in large early release frequency (LERF) was also considered and estimated to be below 1E-7/year.
Cross-Cutting Aspect: H.12 - Avoid Complacency: Individuals recognize and plan for the possibility of mistakes, latent issues, and inherent risk, even while expecting successful outcomes. Individuals implement appropriate error reduction tools. The root cause of the scram was failing to implement a higher-level safety precedence sequence corrective action, such as a design change implementation, to prevent recurrence of a plant scram due to a known design vulnerability.
Enforcement:
Violation: Technical Specification Section 5.4.1.a requires, in part, that written procedures shall be established, implemented, and maintained covering the applicable procedures recommended in Regulatory Guide 1.33, Revision 2, Appendix A, February 1978.
Regulatory Guide 1.33, Revision 2, Appendix A, Section 4 addresses Procedures for Startup, Operation, and Shutdown of Safety-Related BWR Systems, and Section 4.y requires procedures for the reactor protection system.
The licensee established Standard Operating Instruction SOI-C71, RPS Power Supply Distribution, Revision 26. Procedure SOI-C-71, Steps 7.2.31 and 7.3.28, state, "Movement of MG SET TRANSFER switch 1C71-S1, shall be performed in a slow and steady motion.
When placing it in NORM, 3 to 5 degrees of over-travel may cause loss of RPS bus."
Contrary to the above, on August 10, 2023, the licensee failed to follow steps 7.2.31 and 7.3.28 of SOI-C-71, Revision 26, Standard Operating Instruction, and move the MG SET TRANSFER switch in a slow and steady motion. Specifically, the switch was moved in a manner that caused over travel of 3 to 5 degrees and loss of power to both RPS buses with a resultant reactor SCRAM.
Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Observation: 'B' Reactor Feed Pump Trip and Automatic Flow Control Runback From 100 to 75 Percent Power 71153 The inspectors evaluated the 'B' reactor feed pump trip and automatic flow control valve runback from 100 percent power to 75 percent power on January 24, 2024. The reactor experienced a power, pressure, and water level transient. All equipment responded as required to the transient, and the operating crew entered the respective off-normal operating instructions for feed pump malfunction and unexpected change in reactivity. The inspectors identified no plant or operator response issue during the event or eventual plant recovery.
The licensee's troubleshooting effort identified a failed cable in the pump testing circuitry, which actuated the trip solenoid valve due to the ground and directly resulted in the trip of the
'B' reactor feed pump. The licensee replaced the cable, returned the pump to service, and restored reactor power to 100 percent. No more than minor findings or violations were identified by the inspectors.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On April 17, 2024, the inspectors presented the integrated inspection results to Rod Penfield and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Procedures
VLI-E51
Reactor Core Isolation Cooling System
2/14/2024
Fire Plans
Unit-1 RCIC System Pump Room 574-10 Elevation
2/14/2024
Fire Plans
Containment to Drywell Space
2/7/2024
Fire Plans
FPI-0CC
Control Complex Pre-Fire Plan
Revision 13
Fire Plans
FPI-1ST
Steam Tunnel
01/06/2024
Fire Plans
FPI-HB
Heater Bay Building 620 Elevation
01/09/2024
Fire Plans
FPI-RWB
Radwaste Building Pre-Fire Plan
Revision 2
Fire Plans
fz 0CC-2CC-4f
Unit 2 Division 1&4 Cable Chase 6546 Elev.
2/26/2024
Fire Plans
Turbine Bldg. ELE 647
03/28/2024
Procedures
FPI A-B02
Fire Brigade Drills
2/21/2024
Corrective Action
Documents
24-00095
Manhole #1 and Manhole #2 Div. 3 Inspection
01/05/2024
Corrective Action
Documents
24-00210
Inspection Results for DIV 3 Side of Electrical Manhole #2
01/09/2024
Work Orders
200838292
Manhole 1 & 2 / Division 3 Inspection
01/08/2024
Corrective Action
Documents
CR-2024-00351
Unit 2 Plant Vent Isokinetic Declared Inoperable
01/15/2024
Corrective Action
Documents
CR-2024-02641
Post Maintenance Seal Leak on PY-1E12C0003 Residual
Heat Removal B/C Water Leg Pump
03/27/2024
Work Orders
Unit 2 Plant Vent Isokinetic Pump
01/30/2024
Corrective Action
Documents
23-09457
Rod Control and Information System Lockup
2/31/2023
Corrective Action
Documents
24-01329
Division 2 ECCS Outage Delayed Past 50% of LCO due to
Emergent Condition
2/20/2024
Corrective Action
Documents
24-01473
Unit 1 Plant Vent Isokinetic Sample Vacuum Pump Oil Leak
2/26/2024
Procedures
SOI-D17 Section
4.2
Airborne Radiation Monitoring System (Effluents)
Revision 16
Work Orders
200938203
Plant Vent Isokintic Sample Vacuum Pump Leak,
Repair/Replace Parts as Required. Tighten Fitting and Add
Oil.
2/26/2024
Corrective Action
24-00902
Main Turbine EHC Hydraulic Oil Temperature Controller
2/04/2024
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Documents
P44-R437 Is Hunting
Corrective Action
Documents
24-01717
03/03/2024
Corrective Action
Documents
CR-2024-00552
Residual Heat Removal & Reactor Core Isolation Cooling ST
SUPP FIRST DRN SHUTOFF Valve Friction Outside of
Acceptance Criteria
01/21/2024
Corrective Action
Documents
CR-2024-01290
Lube Oil Strainer dp High Alarm Locked in during DIV 2
Diesel Run
2/19/2024
Procedures
PMI-0065-B
Division 2 Diesel Generator Starting Air Dryer Maintenance
2/27/2023
Work Orders
200770226
Maintenance-Starting Air Dryer-1B
2/25/2023
Calculations
34:04
Design of 5ft Manhole all Except #20 + #23
08/21/1975
Drawings
2-0861-0000
UFSAR Figure 2.4-71 Plant Foundation Underdrain System
Revision W
Drawings
SKTCH EMH-1
EMH-1 Junction Box 0JB-5471 - Layout
Revision 0
Engineering
Changes
ECP 22-006-001
Installation of Dewatering System in Electrical Manhole #1
Revision 0
Engineering
Evaluations
Engineering
Evaluation
Request
Notification
601439187
Evaluate Continued Service Waterleg Pump
2/23/2024
Miscellaneous
CFR 50.59
Screen 24-00297
Residual Heat Removal System
Revision 0
Miscellaneous
NOP-LP-4008-01
Change of Notice Form 23-005 EC 22-0026-001 -
Dewatering Electrical Manhole #1
08/31/2023
Corrective Action
Documents
22-05639
Unit 2 OPPS Panel Failed SEL-2411 Relay
07/19/2022
Corrective Action
Documents
23-05637
Unit 2 Startup Transformer Open Phase Protection System
Shutdown due to High Panel Temperature
07/19/2023
Corrective Action
Documents
23-07670
Unable to Adjust Test 2 RPS Instrumentation Potentiometer
during SVI-C51-T0027
10/11/2023
Corrective Action
Documents
23-08559
Div 1 Diesel LB Turbo to Be Installed Appears to Have
Damage to the Mating Surface Area
11/15/2023
Corrective Action
23-08637
Division 1 Diesel Generator Shutdown Based on Abnormal
11/20/2023
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Documents
Noises from Left Bank Turbo
Corrective Action
Documents
23-09183
Unit 2 Startup Transformer Open Phase Panel SEL-2411
Relay Vendor Configuration Issue Discovered During PMT
2/14/2023
Corrective Action
Documents
24-00351
Unit 2 Plant Vent Isokinetic Declared Inoperable
01/15/2024
Corrective Action
Documents
24-00602
Code Required Actions Not Taken for ESW Pump B
Vibrations in Alert Range
01/23/2024
Corrective Action
Documents
24-00654
Control Room Recirculation Relay Found with Nylon Screws
Loose and Free Moving Inside Relay Case
01/25/2024
Corrective Action
Documents
24-00902
Main Turbine EHC Hydraulic Oil Temperature Controller
P44-R437 Is Hunting
2/04/2024
Engineering
Changes
23-1205-000
RWCU Regenerative Heat Exchanger Flange Temporary
Leak Repair
Revision 0
Engineering
Evaluations
601428609
ECP#23-1205 Additional Injection Volume
2/05/2023
Engineering
Evaluations
EER 601435986
EER 601435986 Perp 1520 implemented for MCC EF1D09-
P
01/24/2024
Procedures
EER 000715
Replacement Evaluation for Bailey Controls Control Unit
Model 721003AAAA1
Revision 0
Procedures
GMI-0008
Pressure Relief Device Bench Testing
2/01/2023
Procedures
GMI-0073
V-Belt and Sheave Maintenance
Revision 19
Procedures
PMI-0047
0047 Division 1 & 2 Diesel Generator Turbocharger Cleaning
Intercooler Inspection and Leakage Test
Revision 11
Procedures
PMI-0109
V-Belt and Sheave Inspection
Revision 6
Procedures
SVI-C51-T0027F
APRM F Channel Functional for 1C51-K605F
Revision 13
Procedures
SVI-C51-T0052B
OPRM Channel B Response Time for 1C51-K603B
04/29/2021
Procedures
SVI-E22-T2001
HPCS Pump and Valve Operability Test
Revision 38
Work Orders
200745065
Disassemble / Inspection LB Turbo Div 1 14 Day LCO
11/30/2023
Work Orders
200806478
SVI-P45T2002 ESW B Pump (92D) ESW Pump B and
Valve Operability Test
01/23/2024
Work Orders
200816128
No Work Description Annotated
01/29/2024
Work Orders
200839473
A Momentary Run Is All That Is Intended Come Up
2/07/2024
Work Orders
200854024
SVI-B21T1407C 1 (24M-STB) RPV Low Level 1 Channel C
Response Time For 1B21-N681CX
07/07/2023
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Work Orders
200854265
01/22/2024
Work Orders
200855587
SVI-C85T1314 Mn Turb Bypass Valve OPER
01/06/2024
Work Orders
200872642
Replace Fullers Earth Filter/B33 HPU B SL-1
2/21/2023
Work Orders
200872696
Insp Brushes/Collector Ring Main Gen Alterex
07/06/2023
Work Orders
200872792
A Momentary Run Is All That Is Intended Come Up
2/07/2024
Work Orders
200872793
A Momentary Run Is All That Is Intended Come Up
2/07/2024
Work Orders
200875766
SVI-C41T2001A 2 (92D) Standby Liquid Control A Pump and
Valve Operability Test
2/21/2023
Work Orders
200889509
No Work Description on Respective Block
2/14/2023
Work Orders
200905418
Oil Change, Lube, Inspect Belt and Inspect Muffler
01/30/2024
Work Orders
200925091
No Official Description of Work Description
10/18/2023
Work Orders
200928673
R/1-ECP#23-1205-Rework Welds/Injects
01/08/2024
Work Orders
200935006
Determine the CAUSE of the u2PV Isokinetic Pump Not
Working and Repair/Replace Parts as Required
01/15/2024
Work Orders
200936705
No Work Description Annotated
2/06/2024
Work Orders
ASME OM Code Remove/Replace Relief Valve in Support of
SVI-GEN-T2100
2/20/2024
Miscellaneous
Miscellaneous
OTLC-305-
202406_PY-
SGC1
Evaluation Scenario Guide
2/05/2024
Corrective Action
Documents
CR-2024-01406
RHR B/C Waterleg Pump Leakage Contributes to Primary
Leakage outside Containment
2/22/2024
Corrective Action
Documents
CR-2024-00642
Trip of Reactor Feed Pump Turbine B
01/24/2024