IR 05000254/2023003
| ML23313A154 | |
| Person / Time | |
|---|---|
| Site: | Quad Cities  |
| Issue date: | 11/09/2023 |
| From: | Robert Ruiz NRC/RGN-III/DORS/RPB1 |
| To: | Rhoades D Constellation Energy Generation, Constellation Nuclear |
| References | |
| IR 2023003 | |
| Download: ML23313A154 (28) | |
Text
SUBJECT:
QUAD CITIES NUCLEAR POWER STATION - INTEGRATED INSPECTION REPORT 05000254/2023003 AND 05000265/2023003
Dear David Rhoades:
On September 30, 2023, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Quad Cities Nuclear Power Station. On October 10, 2023, the NRC inspectors discussed the results of this inspection with Brian Wake, Site Vice President, and other members of your staff. The results of this inspection are documented in the enclosed report.
Three findings of very low safety significance (Green) are documented in this report. One of these findings 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 Quad Cities Nuclear Power Station.
If you disagree with a cross-cutting aspect assignment or a finding not associated with a regulatory requirement 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 Quad Cities Nuclear Power Station.
November 9, 2023 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, Robert Ruiz, Chief Reactor Projects Branch 1 Division of Operating Reactor Safety Docket Nos. 05000254 and 05000265 License Nos. DPR-29 and DPR-30
Enclosure:
As stated
Inspection Report
Docket Numbers:
05000254 and 05000265
License Numbers:
Report Numbers:
05000254/2023003 and 05000265/2023003
Enterprise Identifier:
I-2023-003-0058
Licensee:
Constellation Nuclear
Facility:
Quad Cities Nuclear Power Station
Location:
Cordova, IL
Inspection Dates:
July 01, 2023 to September 30, 2023
Inspectors:
Z. Coffman, Resident Inspector
C. Hunt, Senior Resident Inspector
J. Masse, Project Engineer
Approved By:
Robert Ruiz, Chief
Reactor 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 Quad Cities Nuclear Power Station, 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
Unit 2 SBO Breaker Failed to Close During Quarterly Surveillance Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green FIN 05000254,05000265/2023003-01 Open/Closed
[H.8] -
Procedure Adherence 71111.12 A self-revealed finding of very low safety significance (Green) was identified when the licensee failed to perform testing on station blackout (SBO) equipment in accordance with Regulatory Guide (RG) 1.155, Station Blackout, appendix A, Section 2, Instructions,
Procedures, and Drawings. Specifically, the licensee failed to perform a post-maintenance test (PMT) in accordance with established procedures following planned maintenance on feed breaker 7103 on November 15, 2022. As a result, the licensee failed to identify a misalignment of breaker 7103 which occurred following the maintenance. This misalignment prevented the breaker from closing during a Unit 2 station blackout diesel generator quarterly load test on February 15, 2023.
Failure of the Unit 1 Station Blackout Diesel to Obtain Full Load Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green FIN 05000254,05000265/2023003-02 Open/Closed
[P.5] -
Operating Experience 71152A The inspectors identified a finding of very low safety significance (Green) for the licensee's failure to identify and evaluate relevant industry operating experience regarding the site's station blackout (SBO) diesel generators. As a result, during surveillance testing on April 27, 2023, the Unit 1 SBO diesel generator was unable to obtain full rated load due to a failed fuel injector. A similar failure was the subject of an NRC Part 21 Notification in 2017 but was not identified by the licensee or evaluated in the corrective action program (CAP). As a result, the vulnerability was never addressed until the failure on April 27, 2023.
Failure to Correct a Condition Adverse to Quality Associated with a 4 kilovolt (kV) Breaker Fuse Block Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000254,05000265/2023003-03 Open/Closed
[H.5] - Work Management 71152A A self-revealed finding of very low safety significance (Green) and associated non-cited violation of 10 CFR 50, appendix B, criterion XVI, "Corrective Action," was identified for the licensee's failure to correct a condition adverse to quality. Specifically, the licensee failed to replace the trip fuse block in the bus 23-1, cubicle 2, which powers the 2A core spray pump, after identifying in 2007 that the fuse block was susceptible to age-related wear that could prevent the breaker from fulfilling its safety function. As a result, on June 28, 2023, the trip fuse block became loose and prevented the 2A core spray pump from being able to be tripped as designed for load shedding during a design basis loss of coolant accident concurrent with a loss of offsite power.
Additional Tracking Items
None.
PLANT STATUS
Unit 1
The unit began the inspection period at full-rated thermal power, where it remained for the rest of the inspection period, except for short-term power reductions for control rod sequence exchanges, testing, and as requested by the transmission system operator.
Unit 2
The unit began the inspection period at full-rated thermal power. On August 11, 2023, the unit was automatically tripped due to a failure of the Unit 2 essential service system power supply.
The unit returned to full-rated thermal power on August 14, 2023, where it remained except for short-term power reductions for control rod sequence exchanges, testing, and as requested by the transmission system operator.
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 hot temperatures and elevated river debris for the following systems:
intake bay and intake filtration systems on July 14, 2023
71111.04 - Equipment Alignment
Partial Walkdown Sample (IP Section 03.01) (3 Samples)
The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:
(1)safe shutdown makeup pump system on September 27, 2023
- (2) Unit 2B residual heat removal walkdown on September 14, 2023 (3)1B core spray walkdown on August 7, 2023
Complete Walkdown Sample (IP Section 03.02) (1 Sample)
- (1) The inspectors evaluated system configurations during a complete walkdown of the Unit 1 high-pressure coolant injection (HPCI) system on August 15, 2023.
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) Fire Zone 11.3.3, "UNIT 2 RB 544-0 ELEV. NW Corner Room - 2A Core Spray," on July 12, 2023
- (2) Fire Zone 8.2.1.A, "Unit 1 TB 547'-0" ELEV. Condensate Pump Room," on August 8, 2023
- (3) Fire Zone 8.2.8.E, "Unit 1 TB 639' Elev Main Turbine Floor," on August 13, 2023
- (4) Fire Zone 6.3, "Aux Electric Room," on September 13, 2023
- (5) Fire Zone 3.0, "SB 609'-0" Elev. Cable Spreading Room," on September 26, 2023
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)control room observation during Unit 2 startup following a trip on August 13, 2023
Licensed Operator Requalification Training/Examinations (IP Section 03.02) (2 Samples)
- (1) The inspectors observed and evaluated training drills in the simulator on July 11, 2023.
- (2) The inspectors observed and evaluated training drills in the simulator on August 30, 2023.
71111.12 - Maintenance Effectiveness
Maintenance Effectiveness (IP Section 03.01) (4 Samples 1 Partial)
The inspectors evaluated the effectiveness of maintenance to ensure the following structures, systems, and components (SSCs) remain capable of performing their intended function:
- (1) Action Request (AR) 4673482, "U1 SBO [station blackout] Not Able to Obtain Full Load," on August 7, 2023
- (2) AR 4676657, "PSU Scram Discharge Vents and Drains Failed to Reopen," on August 25, 2023
- (3) AR 4554743, "U2 SBO Breaker to Bus 23-1 Failed to Close," on July 5, 2023
- (4) AR 4687703, "Received 902-3 B-16 CS DISCH HDR HI/LO PRESSURE," on September 20, 2023 (5)
(Partial)
AR 4687356, "Lost Light Indications for 2A Core Spray," on September 15, 2023
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) Work Orders (WOs) 4775283-04, 4775283-76, 4813850-01, 5260627-01 on August 21, 2023
71111.13 - Maintenance Risk Assessments and Emergent Work Control
Risk Assessment and Management Sample (IP Section 03.01) (2 Samples)
The inspectors evaluated the accuracy and completeness of risk assessments for the following planned and emergent work activities to ensure configuration changes and appropriate work controls were addressed:
- (1) E-2 certification meeting and risk management for work week 9/10/2023 on August 31, 2023 (2)risk management for work week 9/18/2023 on September 18, 2023
71111.15 - Operability Determinations and Functionality Assessments
Operability Determination or Functionality Assessment (IP Section 03.01) (6 Samples 1 Partial)
The inspectors evaluated the licensee's justifications and actions associated with the following operability determinations and functionality assessments:
- (1) AR 4693019, "1B SBO Starting Air Pressure," on July 28, 2023
- (2) AR 4688157, "MSL Pilot Valve 2-0203-1A Rising Temperature Trend," on August 9, 2023
- (3) AR 4695471, "U2 EDG [emergency diesel generator] Starting Air Header Pressure Low," on August 22, 2023
- (4) AR 4698645, "US EDG Starting Air Header PCV Reads High Out of Band,"
August 26, 2023
- (5) AR 4691426, "1A SBLC [standby liquid control] Pump Flow Rate Above IST Required Action Range," on July 19, 2023
- (6) AR 4701747, "Unit 1 HPCI - Torus Suction Line Failed UT Vent Verification," on September 28, 2023 (7)
(Partial)
AR 4692968, "MOV 2-1001-18A/B Incorrect Use of Close Control Scheme," on August 31, 2023
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)
- (2) Loop 2B residual heat removal service water pump operability test following planned maintenance on July 24, 2023
- (3) Unit 1B standby liquid control pump flow rate test following planned maintenance on August 1, 2023
- (4) Unit 2 HPCI PMT on gland seal exhaust condenser high level switch following troubleshooting on September 1, 2023
- (5) PMT activities after replacing the Unit 1B residual heat removal room cooler outlet valve on September 8, 2023
- (6) Unit 2 125 Vdc battery charger PMT after 4-hour load test on September 13, 2023
- (7) WO 5389091, "Wiring Verification on Torque and Limit Switches on 2-1001-18A," on September 14, 2023
- (8) PMT activities associated with WO 05266486, "Replace 2-1001-65B Low Pressure Discharge Elbow," on September 22, 2023
- (9) PMT activities associated with a planned work window on the 1/2 emergency diesel generator on September 22, 2023
- (10) PMT activities replacing Unit 1B fuel pool radiation monitor after high rad alarm (AR 4704898) on September 26, 2023
71114.06 - Drill Evaluation
Drill/Training Evolution Observation (IP Section 03.02) (1 Sample)
- (1) The inspectors evaluated training drills on August 29,
OTHER ACTIVITIES - BASELINE
===71151 - Performance Indicator Verification The inspectors verified licensee performance indicators submittals listed below:
MS05: Safety System Functional Failures (SSFFs) Sample (IP Section 02.04)===
- (1) Unit 1 (July 1, 2022, through June 30, 2023)
- (2) Unit 2 (July 1, 2022, through June 30, 2023)
MS06: Emergency AC Power Systems (IP Section 02.05) (2 Samples)
- (1) Unit 1 (July 1, 2022, through June 30, 2023)
- (2) Unit 2 (July 1, 2022, through June 30, 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) AR 4673482, "U1 SBO Not Able to Obtain Full Load," on August 8, 2023
- (2) AR 4693375, "WHR [work hour rule] Violation," on July 31, 2023
- (3) AR 4687356, "Lost Light Indication for 2A Core Spray," on September 22, 2023
71152S - Semiannual Trend Problem Identification and Resolution Semiannual Trend Review (Section 03.02)
- (1) The inspectors reviewed operations department performance from January through July 2023 on September 12, 2023.
71153 - Follow Up of Events and Notices of Enforcement Discretion Personnel Performance (IP Section 03.03)
- (1) The inspectors evaluated personnel performance during and after the Unit 2 trip on August 11,
INSPECTION RESULTS
Unit 2 SBO Breaker Failed to Close During Quarterly Surveillance Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green FIN 05000254,05000265/2023003-01 Open/Closed
[H.8] -
Procedure Adherence 71111.12 A self-revealed finding of very low safety significance (Green) was identified when the licensee failed to perform testing on station blackout (SBO) equipment in accordance with Regulatory Guide (RG) 1.155, Station Blackout, appendix A, Section 2, Instructions, Procedures, and Drawings. Specifically, the licensee failed to perform a post-maintenance test (PMT) in accordance with established procedures following planned maintenance on feed breaker 7103 on November 15, 2022. As a result, the licensee failed to identify a misalignment of breaker 7103 which occurred following the maintenance. This misalignment prevented the breaker from closing during a Unit 2 station blackout diesel generator quarterly load test on February 15, 2023.
Description:
In response to the SBO rule outlined in 10 CFR 50.63, Loss of All Alternating Current Power, the licensee installed two non-safety related SBO diesel generators capable of providing power to safety-related buses and safe shutdown loads in the event of a total or partial loss of offsite power concurrent with the unavailability of the stations onsite emergency diesel generators.
On February 15, 2023, the licensee attempted to close the 4160 Volt feed breaker, 7103, during the performance of a quarterly Unit 2 SBO diesel generator surveillance but the breaker did not close. The licensee performed troubleshooting and determined that the breaker was approximately 0.25 inches out from its fully racked in position. The licensee corrected this condition by racking the breaker out and back in, which allowed the breaker to successfully close as required. It took 39 minutes for operators to successfully close breaker 7103 following the discovery of the degraded condition. The licensee documented the condition in the corrective action program (CAP) under issue report AR 4554743.
Breaker 7103 is the non-safety related feed breaker that connects non-safety related bus 71 to safety-related bus 23-1 and allows the Unit 2 SBO diesel generator to power division I safety-related loads. Breaker 7104 is a similar breaker that connects bus 71 to bus 24-1 which is the safety-related bus for division II loads.
Licensee document, NO-AA-10, Quality Assurance Topical Report, states that the licensee is committed to appendices A and B of RG 1.155, Station Blackout." RG 1.155, appendix A, Section 2, states, in part, that inspections, tests, and administrative controls should be prescribed by documented instructions and procedures and should be accomplished with these documents.
Licensee procedure, MA-AA-716-012, Post Maintenance Testing, Section 4.2.4, states that a PMT shall be performed following any corrective and some preventive maintenance activities on plant equipment that may have impacted the equipments ability to perform its intended function. These activities may include maintenance that affects electrical distribution equipment.
The inspectors reviewed issue report AR 4554743 and the circumstances associated with this event. The last time breaker 7103 was racked out for maintenance was on November 15, 2022, per WO 5155649, for local breaker testing in accordance with QCOS 6500-06, 4160 and 480 V Breaker Local Control Test for Appendix R. Both breakers 7103 and 7104 were racked out and back in on the same day, but it was not known at the time that breaker 7103 was approximately 0.25 inches out from its correct alignment.
Following the maintenance, the licensee ran the Unit 2 SBO diesel generator in accordance with QCOS 6620-01, SBO DG 1(2) Quarterly Load Test. This procedure is written to power either the division I or division II safety-related bus through either breaker 7103 or 7104, respectively, but not both simultaneously. The licensee's maintenance strategy for SBO diesel generator load tests alternates the division to be powered on a quarterly basis to equalize run time on plant equipment. Following completion of QCOS 6500-06, the licensee successfully performed a PMT of breaker 7104 by completing QCOS 6620-01 and powering bus 24-1 from bus 71 through breaker 7104. The Unit 2 SBO diesel generator was then shut down without a PMT on breaker 7103.
The inspectors reviewed WO 5155649 and noted that it called for a run of the Unit 2 SBO diesel generator following the completion of the maintenance but did not have specific tasks to perform PMTs on the breakers manipulated. Additionally, during shift turnover, the Unit 2 supervisor on-shift during the maintenance did not communicate the need for a PMT to the oncoming Unit 2 supervisor. Therefore, when it came time to perform the SBO diesel generator run per QCOS 6620-01, the surveillance was run through breaker 7104 based on the licensees maintenance strategy. Operators did not recognize that breaker 7103 also required a PMT since there was not one scheduled for the maintenance that was performed.
Ultimately, the inspectors determined that the licensee failed to perform any PMT, in accordance with MA-AA-716-012, following maintenance activities on breaker 7103 that could have impacted the breakers ability to perform its intended function. This resulted in the misalignment of the breaker not being discovered for approximately 92 days rather than promptly following the maintenance activity.
Corrective Actions: The licensee restored breaker 7103 to proper alignment which allowed it to close as designed. The licensee updated future work orders with the performance of QCOS 6500-06 to verify that PMT instructions exist to preclude missing the PMT again.
Corrective Action References: AR 4554743, U2 SBO Breaker to Bus 23-1 Failed to Close
Performance Assessment:
Performance Deficiency: The inspectors determined that the failure to perform PMT in accordance with documented instructions, procedures, and drawings was a performance deficiency. Specifically, the licensee failed to schedule and perform PMT after activities were performed on breaker 7103 having the potential to impact its intended function.
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. Specifically, when breaker 7103 did not close, the Unit 2 SBO generator could not perform its function to provide power to the division I safety-related bus.
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 screened the finding using exhibit 2 and determined that the finding required a detailed risk evaluation per step 6. Specifically, the inspectors treated the failure of breaker 7103 to close as a loss of the probabilistic risk assessment function of one non-Technical Specification (TS) train of equipment designated as risk-significant in accordance with the licensees maintenance rule program for greater than 3 days. A detailed risk evaluation was performed to assess the significance of the finding. The finding was assumed to result in a degraded condition in which the SBO diesel generator crosstie breaker 7103 would fail to close. The condition was assumed to exist for an exposure period of 92 days.
An NRC senior reactor analyst (SRA) used a recently modified standardized plant analysis risk (SPAR) model to analyze the finding. The model modification was necessary to properly credit post-Fukushima diverse and flexible coping strategies (FLEX) strategies, incorporate FLEX equipment reliability consistent with the information in PWROG-18042-NP, revision 1, FLEX Equipment Data Collection and Analysis, (Agencywide Documents and Management System [ADAMS] ML22123A259), which is considered best available information, and to include all four SBO diesel generator (DG) cross-tie breakers in the common cause component group for CRB-7103. The change in core damage frequency (CDF) due to internal events was estimated to be less than 1E-7/yr. The dominant core damage sequence involved a weather-related loss of offsite power, failure of high-pressure injection systems, and failure of low-pressure injection systems following successful depressurization. At this internal events CDF value, the risk contribution from external events and large early release frequency were not required to be evaluated, however, the NRC was already aware of fire risk information from the licensee that, when considered with the internal events information from SPAR, resulted in a change in core damage frequency that remained below 1E-6/yr.
Cross-Cutting Aspect: H.8 - Procedure Adherence: Individuals follow processes, procedures, and work instructions. Specifically, operators failed to perform the required PMT, per MA-AA-716-012, after completing maintenance activities on plant equipment that may have impacted the equipments ability to perform its intended function.
Enforcement:
Inspectors did not identify a violation of regulatory requirements associated with this finding.
Failure of the Unit 1 Station Blackout Diesel to Obtain Full Load Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green FIN 05000254,05000265/2023003-02 Open/Closed
[P.5] -
Operating Experience 71152A The inspectors identified a finding of very low safety significance (Green) for the licensee's failure to identify and evaluate relevant industry operating experience regarding the site's station blackout (SBO) diesel generators. As a result, during surveillance testing on April 27, 2023, the Unit 1 SBO diesel generator was unable to obtain full rated load due to a failed fuel injector. A similar failure was the subject of an NRC Part 21 Notification in 2017 but was not identified by the licensee or evaluated in the CAP. As a result, the vulnerability was never addressed until the failure on April 27, 2023.
Description:
On April 27, 2023, while performing a Unit 1 SBO diesel generator quarterly load test per QCOS 6620-01, SBO DG 1(2) Quarterly Load Test, the licensee noted that the Unit 1 SBO diesel generator was unable to obtain full load. In addition, the licensee noted that during the subsequent cooldown following the test the engine did not respond as expected. The licensee entered the condition into the CAP under issue report AR 4673482. The 1A and 1B SBO engines are tied together as a tandem SBO unit which are connected to one generator.
Following troubleshooting, the license determined that the cause of the degraded condition was a damaged gear within the fuel injector of cylinder number 7 of the 1A SBO engine. This damaged gear caused the fuel injector to become stuck, which in turn caused the engine to lock up due to having a solid fuel injector linkage design. The degraded condition did not allow the other cylinders in the engine to fire properly as the governor tried to regulate the speed and ramp the engine up to full load. The licensee noted that although the damaged gear was the root of the problem, the lack of spring-loaded fuel injector linkages was a contributing factor to the generator not obtaining full load. The use of spring-loaded injector linkages was a vendor recommended system upgrade which mitigates the consequences of such an event.
Licensee document, NO-AA-10, Quality Assurance Topical Report, states that the licensee is committed to appendices A and B of Regulatory Guide (RG) 1.155, Station Blackout.
RG 1.155, appendix A, Section 8, states, in part, measures should be established to ensure that failures, malfunctions, deficiencies, deviations, defective components, and nonconformance are promptly identified, reported, and corrected.
Licensee procedure PI-AA-115, Operating Experience, Section 3.11, outlines the responsibilities of the site operating experience coordinators. The procedure states, in part, that the site operating experience coordinator initiates an issue report when the station is impacted by a Part 21 notification even if the notification does not specifically call out the station.
The inspectors reviewed the circumstances surrounding the event and the causal evaluation performed by the licensee. The inspectors also reviewed Part 21 Notification, 2017-02-00, dated January 10, 2017 (ADAMS ML17019A351). Notification 2017-02-00 identified a condition reported by Engineering Systems, INC., similar to the degraded condition experienced by the licensee on April 27, 2023. Specifically, Arkansas Nuclear One (ANO)experienced a seized fuel injector on an electro-motive diesel (EMD) generator that adversely affected the ability of diesel generator to carry load. The affected diesel employed a solid fuel injector linkage design. With that design, the seizure of one fuel injector causes the common fuel layshaft to lock and prevented it from rotating. This in turn prevented the engines governor from controlling the fuel delivered to the engine and prevented the diesel generator from adequately controlling and/or carrying the required load. The notification highlighted that many utilities have switched to spring-loaded injector linkages which allow the engine to continue to operate in the event of a frozen injector rack.
The inspectors noted that both Quad Cities and ANO use EMD generators to provide onsite power to safety-related and safe shutdown equipment during emergencies. As such, the degraded condition outlined in Part 21 Notification, 2017-02-00, was applicable to Quad Cities. The inspectors determined that the safety-related emergency diesel generators at Quad Cities have the spring-loaded fuel injector design; however, both SBO diesel generators have the solid fuel injector linkage design. The inspectors reviewed the licensees CAP and determined that although several issue reports were generated in response to the event at ANO by another plant in the Constellation fleet which also employs EMD generators (Dresden Station), there was not a specific issue report generated for the Quad Cities station.
As a result, the licensee was not aware that this Part 21 Notification was applicable to the Quad Cities SBO diesel generators and no actions were taken in the CAP to address the specific vulnerability. Therefore, the inspectors determined that the failure to identify and evaluate relevant industry operating experience regarding the stations SBO diesel generators was a performance deficiency.
Corrective Actions: The licensee replaced the failed fuel injector and satisfactorily retested the Unit 1 SBO diesel generator. The licensee created work orders to upgrade the fuel injector linkages on both SBO diesel generators to the spring-loaded design.
Corrective Action References: AR 4673482, "U1 SBO Not Able to Obtain Full Load"
Performance Assessment:
Performance Deficiency: The inspectors determined that the failure to identify and evaluate relevant industry operating experience regarding the stations SBO diesel generators was a performance deficiency. Specifically, RG 1.155, Station Blackout," appendix A, Section 8, states, in part, that measures should be established to ensure that failures, malfunctions, deficiencies, deviations, defective components, and nonconformance are promptly identified, reported, and corrected. Licensee procedure PI-AA-115, Operating Experience, Section 3.11, states, in part, that the site operating experience coordinator initiates an issue report when the station is impacted by a Part 21 Notification even if the notification does not specifically call out the station.
Contrary to the above, the licensee failed to identify that an NRC Part 21 Notification was applicable to the site's SBO diesel generators and enter the condition into the CAP for evaluation.
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. Specifically, the failed fuel injector prevented the Unit 1 SBO diesel generator from obtaining full load.
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 screened the finding using exhibit 2 and determined this finding was of very low safety significance (Green).
Cross-Cutting Aspect: P.5 - Operating Experience: The organization systematically and effectively collects, evaluates, and implements relevant internal and external operating experience in a timely manner. Specifically, the licensee failed to recognize that Part 21 Notification, 2017-02-00, was applicable to the station SBO diesel generators in 2017.
Additionally, following a review of the licensee's causal evaluation and maintenance rule a(1)determination from the failure on April 27, 2023, the inspectors noted that the site remained unaware of this relevant industry operating experience until it was pointed out by the inspectors during follow up conversations.
Enforcement:
Inspectors did not identify a violation of regulatory requirements associated with this finding.
Failure to Correct a Condition Adverse to Quality Associated with a 4 kilovolt (kV) Breaker Fuse Block Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000254,05000265/2023003-03 Open/Closed
[H.5] - Work Management 71152A A self-revealed finding of very low safety significance (Green) and associated non-cited violation of 10 CFR 50, appendix B, criterion XVI, "Corrective Action," was identified for the licensee's failure to correct a condition adverse to quality. Specifically, the licensee failed to replace the trip fuse block in the bus 23-1, cubicle 2, which powers the 2A core spray pump, after identifying in 2007 that the fuse block was susceptible to age-related wear that could prevent the breaker from fulfilling its safety function. As a result, on June 28, 2023, the trip fuse block became loose and prevented the 2A core spray pump from being able to be tripped as designed for load shedding during a design basis loss of coolant accident concurrent with a loss of offsite power.
Description:
On June 28, 2023, while performing QCOS 1400-01, Core Spray System Flow Rate Test, for the 2A core spray pump, the main control room lost light indication for the pump.
Subsequent troubleshooting by the licensee revealed that the fuse block for the trip coil in bus 23-1, cubicle 2, associated with the 2A core spray pump, had become unseated during breaker operation. The fuse block was reseated, and light indication was restored in the main control room. Following troubleshooting, the surveillance was completed satisfactory. The licensee entered the condition into the corrective action program (CAP) under issue report AR 4687356. The licensee performed a causal evaluation and determined that while the fuse block connection was loose, the 4kV breaker for the 2A core spray pump would not have opened from any electrical trip signals. As such, the degraded condition adversely affected the ability of the Unit 1/2 emergency diesel generator to load shed on a loss of coolant accident with a concurrent loss of offsite power as described in the stations TSs.
The inspectors reviewed the licensees causal evaluation under issue report AR 4687356, and the circumstances surrounding the event. In 2007, the licensee generated multiple IRs to replace the close and trip fuse blocks in the site 4kV buses. The purpose of the replacement was to prevent possible future breaker failures to close or open due to loose connections at the fuse blocks resulting from the age-related wear; a condition adverse to quality identified through fleet operating experience at the Dresden Nuclear Power Station. The licensee specifically generated issue report AR 683402683402on October 11, 2007, to replace the trip and close fuse blocks in safety related 4kV bus 23-1, cubicle 2, for the 2A core spray pump.
Safety-related buses 13-1, 14-1, and 24-1, were also identified to be susceptible to this condition and additional IRs were generated to replace the associated fuse blocks in those 4kV bus cubicles.
The licensee generated issue report AR 511923511923 action item 24, on October 24, 2007, to track the completion of the fuse block replacements until March 13, 2013, where the action item was closed to the work orders already generated in the work control program. However, between 2007 and 2023, the work orders to replace the fuse blocks in three of the four safety related buses were never executed. The inspectors noted that work orders for fuse block replacements associated with bus 13-1 were ultimately moved out of refueling outage Q1R21 in 2011 and were not rescheduled until identified by the licensee during the extent of condition review performed under issue report AR 4687356. Likewise, work orders for fuse block replacements associated with bus 14-1 were ultimately moved out of refueling outage Q1R25 in 2019 and were also not rescheduled until identified by the licensee during the extent of condition performed under issue report AR 4687356. Thus, a condition adverse to quality affecting both safety related bus 13-1 and 14-1 was not being tracked by the licensee in the CAP or the work control program until corrected by actions taken under issue report AR 4687356. Finally, the fuse block replacements for bus 23-1 were moved out of refueling outage Q2R25 in 2020 and rescheduled for refueling outage Q2R27 in 2024, but the trip fuse block in bus 23-1, cubicle 2, associated with the 2A core spray pump, failed prior to replacement.
Overall, the inspectors determined that the fleet operating experience related to loose fuse block connections in safety-related 4kV cubicles applied to the fuse blocks in safety-related bus 23-1, cubicle 2, associated with the 2A core spray pump. A loose connection at a fuse block, due to age-related wear, had the potential to cause a breaker failure and therefore was a condition adverse to quality as defined by the licensees CAP under PI-AA-125. The licensee entered the condition into the CAP in 2007 and scheduled a replacement of the affected fuse blocks during a refueling outage to minimize inadvertent operation of equipment while the unit was online and to minimize the risk to technicians working around energized equipment during the replacement. However, the licensee deferred the replacement of the fuse blocks through multiple refueling outages between 2007 and 2023 until a loose trip fuse block connection caused a failure on June 28, 2023. Therefore, the inspectors determined that the failure to replace the trip fuse block on the 4kV breaker associated with the 2A core spray pump was a performance deficiency.
Corrective Actions: The licensee entered the condition into the CAP under issue report AR 4687356 and performed a causal evaluation. Corrective actions were generated to replace the trip and close fuse blocks in the remaining affected 4kV buses.
Corrective Action References: AR 4687356, "Lost Light Indication for 2A Core Spray," and AR 683402683402 "Replace Close & Trip Fuse Blocks at Bus 23-1 Cub 2"
Performance Assessment:
Performance Deficiency: The inspectors determined that the licensee's failure to replace the trip fuse block in 4kV circuit breaker 23-1, cubicle 2, was a performance deficiency.
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. Specifically, while the breaker for the 2A core spray pump was unable to trip, the ability of the Unit 1/2 emergency diesel generator to sequentially load emergency core cooling system equipment as required following a loss of coolant accident concurrent with a loss of offsite power was adversely affected.
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 that this finding was of very low safety significance (Green).
Cross-Cutting Aspect: H.5 - Work Management: 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 and the need for coordination with different groups or job activities. Specifically, the licensee deferred work orders to replace the affected fuse blocks in safety-related buses 13-1, 14-1, and 23-1 through multiple refueling outages between 2007 and 2023. In addition, for bus 13-1 and 14-1, the licensee failed to reschedule the work after its last deferral and was no longer actively tracking its completion.
Enforcement:
Violation: Title 10 CFR Part 50, appendix B, criterion XVI, Corrective Action, requires, in part, that measures be established to ensure conditions adverse to quality, such as failures, malfunctions, deficiencies, deviations, defective material and equipment, and non-conformances are corrected.
Contrary to the above, from October 11, 2007, to June 28, 2023, the licensee failed to correct a condition adverse to quality. Specifically, the licensee identified fleet operating experience related to loose fuse block connections in safety-related cubicles applied to the fuse blocks in safety related bus 23-1, cubicle 2, associated with the 2A core spray pump. Loose connections at a fuse block, due to age-related wear, had the potential to cause breaker failures to close or open. The licensee entered the condition into the CAP on October 11, 2007, and scheduled a replacement of the affected fuse blocks during a refueling outage to minimize inadvertent operation of equipment while the unit was online and to minimize the risk to technicians working around energized equipment during the replacement. However, the licensee deferred the replacement of the fuse blocks through multiple refueling outages between 2007 and 2023 until a loose trip fuse block connection caused a failure on June 28, 2023.
Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Minor Violation 71152A Work Hour Rule Minor Violation Minor Violation: The inspectors reviewed a violation of Title 10 Code of Federal Regulations (CFR) 26.205(d)(2)(ii) for the licensee's failure to schedule and control work hours for personnel subject to work hour controls. Specifically, on July 29, 2023, the licensee failed to appropriately schedule and control work hours for an equipment operator as defined in station procedure LS-AA-119, Fatigue Management and Work Hour Limits. As a result, the equipment operator filled a position covered by work hour rules with less than the requisite 34-hour rest break in a 9-day period.
Screening: The inspectors determined the performance deficiency was minor. Specifically, the performance deficiency did not adversely affect a cornerstone objective and was similar to minor example 10.a of Inspection Manual Chapter 0612, appendix E.
Enforcement:
This failure to comply with 10 CFR 26.205 constitutes a minor violation that is not subject to enforcement action in accordance with the NRCs enforcement policy.
Observation: Work Hour Rule Violation Issue Follow Up 71152A On July 29, 2023, an equipment operator violated work hour rules by not having the requisite 34-hour rest break in a 9-day period. Specifically, during scheduling of the equipment operators shift, the proposed schedule was incorrectly entered into the site scheduling program. As such, the scheduling system did not flag the proposed schedule as a potential violation of work hour rules. Additionally, the equipment operator was not aware of the work hour requirements for their position and did not perform a self-check of their hours prior to taking the shift. As a result, the individual took the shift with less than the required rest break time per licensee procedure LS-AA-119, Fatigue Management and Work Hour Rules. The licensee entered this issue into the CAP under issue report AR 4693375.
Following the discovery of the work hour rule violation, the individual was replaced with a qualified equipment operator and the shift validated that the activities performed by the individual had not adversely affected safety-related systems, structures, or components and that all rounds data recorded by the individual were valid and accurate. Additional actions taken by the licensee included assigning work hour rule training to all licensed and non-licensed operators on shift.
The inspectors reviewed the circumstances surrounding the event, including the licensees causal evaluation, and actions taken by the licensee in the CAP. The inspectors determined that the actions taken by the licensee were appropriate, given the circumstances, and commensurate with the safety significance of the event.
This issue constitutes a minor violation of regulatory requirements documented in the Inspection Results section of this inspection report.
Observation: Negative Operations Department Performance Trend in Procedural Adherence 71152S The final NRC Safety Culture Policy Statement (SCPS) that was published on June 14, 2011, provides the NRCs expectation that individuals and organizations performing regulated activities establish and maintain a healthy safety culture that recognizes the safety and security significance of their activities and the nature and complexity of their organizations and functions. Because safety and security are the primary pillars of the NRCs regulatory mission, consideration of both safety and security issues, commensurate with their significance, is an underlying principle of the SCPS. NUREG-2165, Safety Culture Common Language, lists the traits, attributes, and examples of a healthy nuclear safety culture.
In accordance with Inspection Procedure (IP) 71152, Problem Identification and Resolution, Section 03.02, the inspectors performed a semiannual assessment of the licensee operations department to identify any potential trends that might indicate the existence of a more significant safety issue. During their review, inspectors determined that there was negative trend in operator behaviors in the area of WP.4, Procedure Adherence, of NUREG-2165, where individuals follow processes, procedures, and work instructions. Specific examples reviewed by the inspectors are provided below. Where applicable, the associated violation or finding is referenced.
AR 4554743, U2 SBO Breaker to Bus 23-1 Failed to Close During an SBO diesel quarterly surveillance the licensee discovered that the Unit 2 SBO diesel bus 71 to bus 23-1 feed breaker was not fully racked in. Later investigation by the licensee determined that the breaker was misaligned following planned maintenance in the previous quarter, and the condition was not discovered because the operations department failed to perform PMT of the breaker as required by the PMT program.
The inspectors also determined that this issue constituted a regulatory Finding, the write up of which can be found in Section 71111.12 of this inspection report.
AR 4557933, Level 4 C&T While hanging a clearance tagout to perform maintenance on the Unit 1 turbine building ventilation system, operators inadvertently isolated the Unit 2 turbine building ventilation system at the same time. This was due to operators manipulating a component in the shared instrument air line between the two units that was not recognized by the tagout preparers.
AR 4563396, Level 4 C&T Event While taking the 1D condensate pump out of service for pre-outage work, operators inadvertently tripped hydrogen injection to the Unit 1 condensate pumps. The licensees investigation revealed that operators failed to review the card notes indicating that the expected plant response after removing the desired fuse for the clearance order was that the hydrogen addition system would trip. Had the notes been reviewed, operators would have identified that the tagout could not be placed as written given the desired system lineup at the time.
AR 4672979, Tagout 02-EHC-FULLERS-027 Deficiency in Preparation After operations hung a tagout to support planned maintenance on the Unit 1 electrohydraulic control (EHC) system, maintenance technicians determined that the tagout was actually written for the Unit 2 EHC system. The licensee determined that during the equipment tagout process, neither the creator, approver, nor the challenger identified that the tagout boundary was created for the wrong unit.
AR 4672799, Tagout 02-RHS-DSWBKR-001 Deficiency in Preparation After operations hung a tagout to support planned work on the 2D residual heat removal service water pump, maintenance technicians identified that neither the suction nor the discharge of the pump was tagged closed as required per procedure. The licensee determined that during the equipment tagout process, operators did not follow all the procedural requirements to ensure that the maintenance boundary was properly established.
AR 4669974, Error in Jumper Manipulation During QCOS 6600-50 While performing surveillance testing on the Unit 1, division II, emergency core cooling system, jumpers for the test were closed in the incorrect order causing the 'B' loop of residual heat removal pumps to start unexpectedly. The error was due to technicians relying on flagging of the jumper locations with tape instead of verifying each jumper location against the appropriate steps in the procedure. Contributing to this, the operations supervisor failed to enforce human performance standards by allowing the technicians to use flagging instead of strict procedural adherence.
AR 4675690, Shift Staffing Operations department failed to have a shift technical adviser on site for greater than 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> because of multiple incomplete or inadequate turnovers between licensed operators. The inspectors determined that this issue constituted a violation of regulatory requirements as documented in NRC Integrated Inspection Report 05000254/2023002, 05000265/2023002.
AR 4693375, WHR Violation Where an equipment operator violated work hour rules by not having the minimum required breaks within a 9-day period. The licensee determined that gaps in attention to detail and self-verification resulted in the individuals hours not being entered into the scheduling tool correctly; therefore, the built-in software did not flag the individuals hours as expected.
Additionally, the equipment operator was not keeping tracking of their hours worked and was not aware that the work hour rule was applicable to their position.
The inspectors determined that this issue constituted a minor violation documented in this inspection report under Section 71152.
The licensee documented a corrective action program evaluation (CAPE) under issue report AR 4669326 identifying a similar adverse trend with human performance behaviors in the operations department. The licensee attributed two causes to the trend: 1) operators do not always value procedures and follow them with rigor to prevent events and 2) operations department leaders do not always enforce excellence standards in the use of human performance tools and supervisors have failed to hold personnel accountable for behaviors that deviate from the standards. Licensee actions to address the adverse trend have included one-on-one interviews with operations personnel, reinforcing operator fundamentals, and leadership fundamental assessments for first line supervisors.
The inspectors continue to monitor operator performance in this area.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On October 10, 2023, the inspectors presented the integrated inspection results to Brian Wake, Site Vice President, and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Engineering
Changes
Review of Capabilities of Intake Components to Perform
Design Function
Procedures
Seasonal Readiness
Corrective Action
Documents
HPCI Condensate Pump Did Not Auto Start
08/31/2023
M-46
DIAGRAM OF HIGH-PRESSURE COOLANT INJECTION -
HPCI PIPING
05/05/1998
Drawings
M-70
Diagram of Safe Shutdown Make-Up Pump System
HPCI Turning Gear Performance on HPCI System Operability
Engineering
Changes
U1 HPCI SIGNAL CONVERTER REPLACEMENT
LOCKED EQUIPMENT PROGRAM
QCOP 1000-50
Unit Two RHR System Preparation for Standby Operation
QCOP 2900-01,
Unit 1(2)
Safe Shutdown Makeup Pump System Preparation for Standby
Operation
QCOS 1000-26
RHR Valve Position Verification
QCOS 1000-49
Cold Shutdown RHR System Check Valve Test
Procedures
QCOS 2300-10
HPCI Monthly Valve Position Verification
QCOS 1400-10
CORE SPRAY OPERABILITY VERIFICATION
HPCI LOGIC FUNCTIONAL TEST
05/10/2023
CORE SPRAY PUMP B FLOW RATE (IST)
05/26/2023
SAMPLE HPCI TURB MN PUMP GEAR SET RESVR OIL
09/19/2023
HPCI VENT VERIFICATION
07/27/2023
1B CS VALVE LINEUP VERIFICATION (NO VENTING)
07/20/2023
TSAR, SAFETY SYSTEM MANUAL VALVE POSITION
VERIFICATION
08/14/2023
SAFETY SYSTEM MANUAL VALVE POSITION
VERIFICATION
09/11/2023
Work Orders
HPCI SYSTEM TURBINE OVERSPEED TEST
11/27/2012
Fire Plans
FZ 3.0
Cable Spreading Room
08/2022
FZ 6.3
Aux Electric Room
08/2022
Fire Plans
FZ 8.2.8.E
Unit 1 TB 639' Elevation Main Turbine Floor (Outside Shield
Wall)
08/2022
U2 SBO Breaker to Bus 23-1 Failed to Close
2/15/2023
U1 SBO Not Able to Obtain Full Load
04/27/2023
PSU Scram Discharge Vents and Drains Failed to Reopen
05/09/2023
1-1402-65B Stop Check Sticks in Closed Position
05/24/2023
Lost Light Indication for 2A Core Spray
06/28/2023
Received 902-3 B-16 CS DISCH HDR HI/LO PRESSURE
06/29/2023
Post-Maintenance Testing
Corrective Action
Documents
QCOS 6500-06
4160 and 480 V Breaker Local Control Test for Appendix R
M-46, Sheet 2
Diagram of High-Pressure Coolant Injection HPCI Piping
05/14/1998
M-78
Diagram of Core Spray Piping
06/06/2005
Drawings
QCAN 901(2)-3
B-16
Core Spray Discharge Header High/Low Pressure
Miscellaneous
CS1400: Core
Spray
Core Spray Maintenance Rule Functional Failure Definition
Maintenance Rule Implementation Per NEI 18-10
Maintenance Rule Implementation Per NEI 18-10
Maintenance Rule 18-10 - Performance Monitoring and
Dispositioning Between (a)(1) and (a)(2)
OP-QC-102-106
Operator Response Time Program at Quad Cities
QCOP 0300-28
Alternate Control Rod Insertion
Procedures
QCOS 1400-10
Core Spray Operability Verification
Cut/Weld Sensing Lines to Support Turbine Overhaul
03/27/2023
Cut Line 1-2305-10"-B to Support Removal of 1-2314 Valve
03/28/2023
Replace 1A RHRSW Suction Piping; 1-1002-24"-L
04/01/2023
00185137-02, Com, 4160 & 480 Volt BRKR Local Control Test
(SBO Work Window)
11/16/2022
Work Orders
Replace HPCI Drain "Pot" 1-2365
04/10/2023
Corrective Action
Documents
CO 02-RHS-B PMP-003 Effects RMA Checklist
09/18/2023
Calculations
QCD-1100-M-
28
Calculation Of Corrected Flow Rate due to Changes in Specific
Gravity from The Sodium Pentaborate Solution for SBLC Test
Flowmeter, FI 1-1160
2/15/1997
Unit 1 HPCI - Torus Suction Line Failed UT
08/17/2015
Unit 2 SBLC Test Flowmeter Found Leaking During Run
09/01/2022
SBLC Spare Flowmeter is Degraded
05/22/2023
SBLC Flowmeter Degraded Condition
05/23/2023
New SBLC Flowmeter Defective from Storeroom
05/24/2023
EOID: Unit 2 Enrivons Recorder Pnt. 5 at HIGH SPEC
06/13/2023
MSL Pilot Valve 2-0203-1A Rising Temperature Trend
07/01/2023
2-203-1A Pilot Valve Temp at 180F
07/08/2023
1A SBLC Pump Flow Rate Above IST "Required Action
Range"
07/19/2023
QDC Unit 1 SBLC Pump Flow Data Scatter
07/24/2023
U2 MSIV 1A Pilot Valve Temp is Indicated at 195F
07/24/2023
MOV 2-1001-18A/B Incorrect Use of Close Control Scheme
07/24/2023
NRC ID: 1B SBO Starting Air Pressure
07/27/2023
Follow Up to IR 4689372 2-0203-1A Temp Increasing
08/02/2023
U2 EDG Starting Air Header Pressure Low
08/09/2023
U2 EDG Starting Air Header PCV Reads High Out of Band
08/26/2023
Unit 1 HPCI - Torus Suction Line Failed UT Vent Verification
09/11/2023
Corrective Action
Documents
AR 924101924101Unit 1 HPCI - Torus Suction Line - Failed UT Verification
06/25/2009
Key Diagram SBO 480V AC SWGR 65 And MCC 65-1 FRONT
2/18/1997
Drawings
M-3032
DIAGRAM OF SBO DG ENGINE STARTING AIR PIPING AND
INSTRUMENTATION
06/07/2002
NRC GL 08-01 Venting and Gas Accumulation Evaluation for
Engineering
Changes
Design Engineering Review of ESI Functional Qualification
Report 124245-QR-1 and Seismic Report SR-08-01 For DG Air
Start Motors, CID 1438384-1
000
Engineering
Evaluations
EA 639420
Operability Evaluation of the 2-0203-1A Main Steam Isolation
Valve Pilot Valve
Miscellaneous
C0278
Station Blackout Diesel Generator Vendor Manual and
Auxiliaries
10/14/2015
Operability
Evaluations
639697
OpEvap for IR 04698645
Operability
Evaluations
QDC-4600-M-
1112
Design Review of Emergency Diesel Generator Starting Air
System Capability
IST Pump Evaluation Form
QCOP 6600-12
Diesel Generator Air Start System Pressure Verification
QCOP 6620-06
SBO DG Starting Air System Regulated Pressure Verification
Procedures
QCOS 1100-07
SBLC Pump Flow Rate Test
MM Annual Inspection of Receiver Tank 1-4680-21B
05/18/2023
MM Replace Relief Valve 1-4689-26B
05/10/2023
A SBLC PUMP FLOW RATE COMPREHENSIVE (IST)
07/19/2023
EM Troubleshoot Water in Oil for SBO Starting Air Compressor
Motor 1B
05/03/2023
MM Inspect and Clean the U1 B SBO Starting Air Compressor
05/18/2023
HPCI System UT Vent Verification
09/11/2023
QCOS 6620-01 SBO DG Quarterly Load Test
07/30/2023
Work Orders
Verify Wiring on Torque and Limit Switches On 2-1001-18A
Match Schematic Diagram 4E-2438J Sheet 2
09/14/2023
Degraded Union On 1-B RHR Room Cooler
09/07/2023
1/2 EDG Load Test Aborted WO 5396055-01
09/22/2023
Corrective Action
Documents
RIS 1-1705-16B Erratic Causing RB Vent Trip & SBGT Start
09/25/2023
Corrective Action
Documents
Resulting from
Inspection
RA24 NRC Question for Ops PMT
08/02/2023
QCIS 1700-07
Reactor Building Ventilation and Fuel Pool Radiation
Monitoring Calibration and Functional Test
QCOP 6900-41
Unit 2 125 VDC Electrical System
QCOS 1000-04
RHR Service Water Pump Operability Test
QCOS 1000-04
RHR Service Water Pump Operability Test
QCOS 1000-06
RHR Pump / Loop Operability Test
QCOS 1000-28
RHR Service Water Pump Comprehensive/Performance Test
QCOS 1000-50
Low-Medium Risk RHR Powered Operator Valve Test
QCOS 1100-07
SBLC Pump Flow Rate Test
Procedures
QCOS 2300-15
HPCI Drain Pot/Steam Line Drain Level Switch, Valve, and
Alarm Functional Verification
QCOS 5750-09
ECCS Room and DGCWP Cubicle Cooler Monthly
Surveillance
4kV Breaker 232
07/30/2023
Work Orders
Replace 2-1001-65B Low Pressure Discharge Elbow
09/19/2023
71151
Corrective Action
Documents
Unit 2 EDG Identification of MSPI Discrepancy for O.6.18
08/31/2023
EDG FUEL INJECTOR CONTROL LINKAGE
VULNERABILITY IDENTIFIED
01/17/2017
U1 SBO Not Able to Obtain Full Load
04/27/2023
U1 SBO FUEL INJECTOR CTRL LINKAGE VULNERABILITY
IDENTIFIED
06/28/2023
U2 SBO FUEL INJECTOR CTRL LINKAGE VULNERABILITY
IDENTIFIED
06/28/2023
Lost Light Indication for 2A Core Spray
06/28/2023
WHR Violation
07/29/2023
Corrective Action
Documents
AR 511923511923Plant Engineering Group Actions
07/21/2006
U2 SBO Breaker to Bus 23-1 Failed to Close
2/15/2023
Level 4 C&T
2/28/2023
Level 4 C&T Event
03/19/2023
Potential Adverse Trend With 'HU' Behaviors in Operations
04/11/2023
Error in Jumper Manipulation during QCOS 6600-50
04/13/2023
Tagout 02-RHS-DSWBKR -001 Deficiency in Preparation
04/25/2023
Tagout 02-EHC-FULLERS-027 Deficiency in Preparation
04/25/2023
Shift Staffing
05/04/2023
Corrective Action
Documents
WHR Violation
07/28/2023
Calibration
Records
4696165
As-Found Condition U2 ESS Inv PS Board
08/13/2023
Corrective Action
Documents
Design Enactment to Moisture Separator High Alarms
08/20/2023
M-61
DIAGRAM OF EXTRACTION STEAM PIPING
08/16/2000
M-64
DIAGRAM OF CONDENSATE BOOSTER PIPING
08/28/1998
Drawings
M-66
DIAGRAM OF HEATER DRAIN PIPING
01/29/2002
Modify Unit 1 HP/LP Feedwater Heater Logic Power Feeds
From UPS
Engineering
Changes
Feedwater Heater Trip SPV (BOP Trip Logic)
Engineering
Evaluations
QDC-78434
Failure Analysis of Logic Power Supply for Inverter
09/05/2023
SER 08/11/2023
Significant Events Recorder Data during the scram on
August 11, 2023.
08/11/2023
Miscellaneous
Support/Refute
08/11/2023
Support / Refute Template for the August 11 Scram
08/11/2023
QCAN 901(2)-6
Moisture Separator 1(2)B High Level
Procedures
TIC 3729
Preventative Maintenance Inspection of Uninterruptible Power
Supply for E.S.S.
08/12/2023
Heater Level Control Balance of Plant W: S2HTR1IM
04/21/2022
IM Troubleshoot ISV #5 LVDT
08/12/2023
Intermediate Stop Valve #5 Test Solenoid
08/11/2023
MM Replace Shut Off Valve on Intermediate Stop Valve #5
08/12/2023
MM Uncouple / Recouple 2-5699-CIV5 & ISV5
08/13/2023
Work Orders
PSU: IM Troubleshoot 2A MSDT Emergency LCV Slow to
Respond
08/11/2023