IR 05000282/2023011
| ML23131A329 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 05/16/2023 |
| From: | Hironori Peterson NRC/RGN-III/DORS/RPB3 |
| To: | Domingos C Northern States Power Company, Minnesota |
| References | |
| IR 2023011 | |
| Download: ML23131A329 (1) | |
Text
SUBJECT:
PRAIRIE ISLAND NUCLEAR GENERATING PLANT - BIENNIAL PROBLEM IDENTIFICATION AND RESOLUTION INSPECTION REPORT 05000282/2023011 AND 05000306/2023011
Dear Christopher P. Domingos:
On April 20, 2023, the U.S. Nuclear Regulatory Commission (NRC) completed a problem identification and resolution inspection at your Prairie Island Nuclear Generating Plant and 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.
The NRC inspection team reviewed the stations problem identification and resolution program and the stations implementation of the program to evaluate its effectiveness in identifying, prioritizing, evaluating, and correcting problems, and to confirm that the station was complying with NRC regulations and licensee standards for problem identification and resolution programs.
Based on the samples reviewed, the team determined that your staffs performance in each of these areas adequately supported nuclear safety.
The team also evaluated the stations processes for use of industry and NRC operating experience information and the effectiveness of the stations audits and self-assessments.
Based on the samples reviewed, the team determined that your staffs performance in each of these areas adequately supported nuclear safety.
Finally, the team reviewed the stations programs to establish and maintain a safety conscious work environment, and interviewed station personnel to evaluate the effectiveness of these programs. Based on the teams observations and the results of these interviews the team found no evidence of challenges to your organizations safety conscious work environment. Your employees appeared willing to raise nuclear safety concerns through at least one of the several means available.
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.
May 16, 2023 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 Prairie Island Nuclear Generating Plant.
This letter, its enclosure, and your response (if any) will be made available for public inspection and copying at http://www.nrc.gov/reading-rm/adams.html and at the NRC Public Document Room in accordance with Title 10 of the Code of Federal Regulations 2.390, Public Inspections, Exemptions, Requests for Withholding.
Sincerely, Hironori Peterson, Chief Reactor Projects Branch 3 Division of Operating Reactor Safety Docket Nos. 05000282 and 05000306 License Nos. DPR-42 and DPR-60
Enclosure:
As stated
Inspection Report
Docket Numbers:
05000282 and 05000306
License Numbers:
Report Numbers:
05000282/2023011 and 05000306/2023011
Enterprise Identifier:
I-2023-011-0034
Licensee:
Northern States Power Company, Minnesota
Facility:
Prairie Island Nuclear Generating Plant
Location:
Welch, MN
Inspection Dates:
April 03, 2023 to April 20, 2023
Inspectors:
M. Abuhamdan, Reactor Inspector
A. Dahbur, Senior Reactor Inspector
L. Haeg, Senior Project Manager
C. Norton, Senior Resident Inspector
K. Pusateri, Resident Inspector
Approved By:
Hironori Peterson, Chief
Reactor Projects Branch 3
Division of Operating Reactor Safety
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting a biennial problem identification and resolution inspection at Prairie Island Nuclear Generating Plant, in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRCs program for overseeing the safe operation of commercial nuclear power reactors. Refer to https://www.nrc.gov/reactors/operating/oversight.html for more information.
List of Findings and Violations
Failure to Incorporate Design Bases for Door 283 Into Procedures Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000282,05000306/2023011-01 Open/Closed None (NPP)71152B The inspectors identified a finding of very low safety significance (Green) and an associated non-cited violation (NCV) of Title 10 of the Code of Federal Regulations (10 CFR) Part 50,
Appendix B, Criterion III, Design Control, when the licensee failed to incorporate the design basis function of Door 286 into plant procedures. This incorporation into procedures was necessary to ensure that the screenhouse ventilation system (ZR) design function would be maintained to supply required ventilation to the safety-related cooling water pump rooms in the plant screenhouse.
Additional Tracking Items
None.
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 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.
OTHER ACTIVITIES - BASELINE
71152B - Problem Identification and Resolution Biennial Team Inspection (IP Section 03.04)
- (1) The inspectors performed a biennial assessment of the effectiveness of the licensees Problem Identification and Resolution program, use of operating experience, self-assessments and audits, and safety conscious work environment.
Problem Identification and Resolution Effectiveness: The inspectors assessed the effectiveness of the licensees Problem Identification and Resolution program in identifying, prioritizing, evaluating, and correcting problems. The inspectors also conducted a 5-year review of Units 1 and 2 components cooling water system. The corrective actions for the following non-cited violations (NCVs), minor violations, and findings were evaluated as part of the assessment: NCV 2022010-02, MV 2021-004-04.
Operating Experience: The inspectors assessed the effectiveness of the licensees processes for use of operating experience.
Self-Assessments and Audits: The inspectors assessed the effectiveness of the licensees identification and correction of problems identified through audits and self-assessments.
Safety Conscious Work Environment: The inspectors assessed the effectiveness of the stations programs to establish and maintain a safety-conscious work environment.
INSPECTION RESULTS
Assessment 71152B Assessment of the Corrective Action Program Effectiveness of Problem Identification Overall, the station was effective at identifying issues at a low threshold and was properly entering them into the corrective action program (CAP) as required by station procedures.
During interviews, workers were familiar with how to enter issues into the CAP and stated that they were encouraged to use it to document issues. During plant walkdowns, the team observed that issues were being identified in the field and that they were being properly addressed in the CAP. The team determined that the station was generally effective at identifying negative trends that could potentially impact nuclear safety. For the areas reviewed, the team did not identify any issues in problem identification.
Effectiveness of Prioritization and Evaluation of Issues In-depth reviews of a risk-informed sampling of action requests work orders, and root and apparent cause and condition evaluations were completed. The team determined that the licensee had established a low threshold for entering deficiencies into the CAP, that the issues were generally being appropriately prioritized and evaluated for resolution, and that corrective actions (CAs) were implemented to mitigate the future risk of issues occurring that could affect overall system operability and/or reliability.
The inspectors noted that issues were properly screened with most either classified as conditions adverse to quality (CAQ) or non-corrective action program (NCAP) items. Through a selective review of CAP and NCAP items, the inspectors identified one example where the licensee's screening failed to identify a CAQ issue. Specifically, CAP 501000069662, related to 122 spent fuel pool (SFP) wide range level indicator locked up, was initially classified as a non-condition adverse to quality (NCAQ) issue. Based on further review, as the associated equipment was part of FP-BDB-EQP-01, "Equipment Important to Beyond Design Basis (BDB) Compliance," the CAP was determined that it should have been classified as a CAQ. This issue was documented in CAP 501000071987.
The inspectors also did a selective review of issues identified by the NRC either documented as observations or for which findings or other enforcement was issued. These issues were properly documented and screened in the CAP.
Issue evaluations were generally sound and of good quality. Most issues were screened as low significance and were assigned a work group evaluation (the lowest level of review);more significant issues were assigned an apparent or if highly significant, a root cause evaluation. The inspectors verified that the assigned evaluations were consistent with the significance of the issue as defined in the licensees process.
The inspectors did identify one example where the licensee had inadequately evaluated a CAQ. Specifically, CAP 501000056948, related to a wrong 24V light bulb installed in 120V socket, concluded that the issue was understood without further evaluation necessary, and that a detailed extent of condition was not needed. As such, no further actions were generated. Failure to quarantine the incorrect light bulbs allowed a latent condition to exist until Instrument and Control technicians later identified that a 24V light bulb was being placed in a 120V light socket. In addition, the condition evaluation also did not consider whether it was appropriate for a transient in non-safety related circuit (light bulb for radiation monitor) to cause the safety-related inverter to transfer to the inverter internal bypass source. In addition, objective evidence that the inverter worked as designed was not included with the condition evaluation. This issue was documented in CAP 501000072453.
Effectiveness of Corrective Actions The team concluded that the licensee was generally effective in developing CAs that were appropriately focused to correct the identified problem and to address the root and contributing causes for significant CAQ to preclude repetition. The licensee generally completed CAs in a timely manner and in accordance with procedural requirements commensurate with the safety significance of the issue. For NRC-identified issues, the team determined that the licensee generally assigned CAs that were effective and timely. The inspectors also did a selective review of CAs that were still open at least two years after the issue was identified to verify that it was appropriate for these items to remain open, and that the licensee was managing them correctly; no issues were identified.
However, the inspectors noted that there were several minor examples where CAP program requirements as stated in FP-PA-ARP-01, "CAP Process," had not been followed:
CAP 500001451829, "PART 21 REPORT-Battery Misaligned Separator Plate," was closed without actions or documentation of actions taken, or sufficient documentation for the basis of non-performance. Further review identified that, in alignment with the vendor recommendations, the station was monitoring the cell voltage monthly and tracking this replacement under a separate CAP 501000011209. This issue was documented in CAP 501000072095.
A maintenance notification (10164526) was generated from CAP 501000052128, "122 Battery Room Chiller Tripped," and captured work conducted to restore the system to proper operation; however, the notification did not roll to a record to capture how the CAQ was corrected.
A minor violation of Procedure H10.1 ASME Inservice Testing Program, Section 11.1.2 and American Society of Mechanical Engineers (ASME) Code, Section ISTC-5115 Corrective Action, was identified by the inspectors for the licensee failure to take appropriate corrective action in accordance with the ASME Code requirements for a valve that failed the Inservice test. During Surveillance 1151A, "Train A Cooling Water System Quarterly Test," CV-31652 11 Cooling Water Strainer Backwash Valve, failed the limit stroke time. The valve open stroke time was 2.56 seconds, the limit stroke time is 2.0 seconds. The licensee documented this failure in CAP 501000071174 and declared the valve inoperable per IST and determined that although control valve CV-31652 was inoperable, the 11 cooling water strainer was capable of meeting all required safety functions and remain operable without replacing/repairing or determining the cause of the deviation to show the valve operating acceptably as required per H10.1 and the ASME code. A maintenance notification was generated to replace the valve. The work order is currently scheduled for July of 2023. The inspectors determined that this issue is minor because the overall system is operable and capable to meet all required safety functions and there is a work order to replace the valve in near future and the licensee initiated an action to monitor and test the valve monthly until it is replaced.
Assessment 71152B Assessment of Operating Experience and Self-Assessment and Audits The inspectors reviewed operating experience (OpE) captured in the corrective action program (CAP) and sampled OpE from NRC, industry, vendors, and third-party groups. Overall, for the samples selected, the OpE was appropriately screened and evaluated for applicability, and was effectively used by the station. It was also noted that it was properly considered as a potential precursor in issue evaluations, and during interviews and observations of daily plant meetings, the inspectors concluded that it was seen as a useful learning tool and being used appropriately in daily plant activities.
Nuclear Oversight audits and department self-assessments were generally of good quality, thorough and critical with identified issues being properly dispositioned in the CAP. The audits and assessments were performed in accordance with licensee procedures. Of note, the inspectors observed that the overall conclusions of the licensees self-assessment of the CAP program done prior to this NRC inspection, was consistent with the inspectors observations.
No violations or findings were identified.
Assessment 71152B Assessment of the Safety Conscious Work Environment The team assessed safety conscious work environment (SCWE) at Prairie Island. The team conducted individual interviews and focus groups discussions. The team reviewed corrective action program (CAP) documents, nuclear safety culture monitoring panel reports, the results of pulse surveys, the 2022 safety culture assessment, and CAP documents written as a result of the 2022 assessment. The team did not identify any SCWE issues. The team concluded that an environment exists at Prairie Island where personnel are free to raise nuclear safety concerns without fear of retaliation. No issues of concern were identified.
Assessment 71152B Assessment of the 5-Year Review of Cooling Water System The inspectors performed an expanded 5-year review of the Units 1 and 2 cooling water systems; specifically, by performing system walk-downs and evaluating condition reports, engineering changes, and work orders. Overall, the inspectors determined that the licensee was effectively managing issues associated with this system. The inspectors did not identify any findings or violations.
Failure to Incorporate Design Bases for Door 283 Into Procedures Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000282,05000306/2023011-01 Open/Closed None (NPP)71152B The inspectors identified a finding of very low safety significance (Green) and an associated non-cited violation (NCV) of Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Appendix B, Criterion III, Design Control, when the licensee failed to incorporate the design basis function of Door 286 into plant procedures. This incorporation into procedures was necessary to ensure that the screenhouse ventilation system (ZR) design function would be maintained to supply required ventilation to the safety-related cooling water pump rooms in the plant screenhouse.
Description:
Door 286 is a screened metal door which allows air flow through it and serves as part of the intake air flow path to the safety-related cooling water pump rooms in the plant screenhouse.
On March 27, 2023, a plant employee placed an approximately 1-square foot sign on Door 286 which partially blocked flow to the cooling water pump rooms. This sign remained on Door 286 until it was identified and removed on March 30, 2023. The licensee wrote QIM 501000071836 to document the issue in the corrective action program (CAP). The licensee wrote that, "The analysis for the ZR system, ENG-ME-178, 'Safeguards Screenhouse Ventilation Analysis' revision 1, used test data for air flow rates through door 286 obtained in 2007, and the analyzed configuration of Door 286 and the associated flow area of the door does not include the reduction in flow area from the sign."
Calculation ENG-ME-178, "Safeguards Screenhouse Ventilation Analysis" revision 1, stated, "The purpose of this calculation was to validate the equipment in the safeguards area of the Screenhouse will be capable of performing its required design function with the post-accident room temperatures predicted in the calculation."
The inspectors noted that the same issue had occurred on July 30, 2017, in a licensee-documented CAP, 500001391945, Sign on Door 286 Partially Blocking Flow. The CAP identified that the sign found on the door had not been installed during ventilation testing in 2007 and therefore constituted partial blockage of a design-basis credited flow path.
Corrective actions from the CAP included removal of the sign and performed a condition evaluation to determine past operability. Engineering determined no inoperability had occurred and the CAP was closed.
During the inspection, the NRC inspectors identified that Door 286 was not designated as a safeguards ventilation zone door per procedure H62, "Site Doors", revision 6, even though it met the description for that type of door. Section 4.11 states, "These doors provide ventilation paths and boundaries for safeguards equipment in the Screenhouse."
Corrective Actions: The licensee entered this issue into the corrective action program as Quality Issue 501000071836 and implemented actions to ensure Door 286 would be updated to identify it as a flow path credited as part of the safety-related screenhouse ventilation analysis and identify that no additional signs should be placed on the door.
Corrective Action References: Quality Issue 501000071836, 23PIR Door 286 Sign Blocking Flow Path
Performance Assessment:
Performance Deficiency: The inspectors determined that the licensees failure to incorporate the design Basis function of Door 286 into plant procedures was contrary to 10 CFR Part 50, Appendix B, Criterion III, Design Control, and a performance deficiency.
Screening: The inspectors determined the performance deficiency was more than minor because if left uncorrected, it would have the potential to lead to a more significant safety concern. Specifically, the failure to assure that plant procedures incorporated the design basis of Door 286 as a critical ventilation flow path could have allowed for the obstruction of the safety-related cooling water pump room in the plant screenhouse to the point of inoperability.
Although the as-found flow area was above that assumed in design basis calculations, the licensee did not have procedural controls in place to maintain the ventilation flow path area above that required in the accident analysis. And absent NRC intervention, the Door 286 flow path could affect the capability of the cooling water system to perform its safety functions.
Significance: The inspectors assessed the significance of the finding using Inspection Manual Chapter 0609 Appendix A, The Significance Determination Process (SDP) for Findings At-Power. Specifically, the inspectors determined the finding was very low safety significance (Green) because the inspectors answered NO to question A.1 of Exhibit 2, Mitigating Systems Screening Questions.
Cross-Cutting Aspect: Not Present Performance. No cross-cutting aspect was assigned to this finding because the inspectors determined the finding did not reflect present licensee performance.
Enforcement:
Violation: Title 10 CFR Part 50, Appendix B, Criterion III, Design Control, requires in part, that measures shall be established to assure that applicable regulatory requirements and the design basis are correctly translated into procedures and instructions.
Contrary to the above, from July 30, 2013 (estimated) through April 19, 2023, the licensee failed to assure applicable design basis requirements were correctly translated into procedures and instructions. Specifically, the licensee did not correctly translate the safeguards ventilation door design basis requirements into procedures, and this was necessary to assure the safety-related screenhouse ventilation system (ZR) and safety-related cooling water systems would continue to be able to perform design functions.
Enforcement Action: This violation is being treated as an NCV, consistent with Section 2.3.2 of the Enforcement Policy.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
On April 20, 2023, the inspectors presented the biennial problem identification and resolution inspection results to Christopher P. Domingos, Site Vice President and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
500001470250
4.16 kV Lower Voltage Limit Restricts 34
03/16/2015
501000031487
CV-31653 Stroked Slow During SP 1151A
09/05/2019
501000039794
Part 21 Eval of EQ Rosemont Transmitters
04/17/2020
501000049399
NRC Communication on SFP Indication
03/11/2021
501000050482
Action Not Performed as Written
04/13/2021
501000050543
1HC-945 Has 63% Output w/Setpoint at 0
04/15/2021
501000052128
2 Batt RM Chiller Tripped
05/16/2021
501000052665
2-S Relay Rm U/C Fans Not Running
05/29/2021
501000052865
FWP Motor Stator Temps
06/05/2021
501000055583
EDG Equipment Trend for D6
08/28/2021
501000056654
Turbine Driven AFW Start Signal SP 2083A
10/03/2021
501000056948
Inverter Bypassed
10/08/2021
501000057291
EL 88 Battery Low Electrolyte Level
10/15/2021
501000057355
Loss of Power to 2RY Transformer
10/17/2021
501000061303
Part 21 Lists Prairie Island Impacted
03/14/2022
501000061742
(ACE) Comp Not Performed After 22 DDCLP Maint
03/28/2022
501000062448
MDFP Panel NFPA Code Issue
04/21/2022
501000062738
Incorrect Voltage Lamps Found in CR
05/03/2022
501000062784
SP 1091 Complete Unsat
05/04/2022
501000064478
22 NSCA Gen Obs LA.2
07/06/2022
501000064497
07/06/2022
501000064513
07/06/2022
501000064520
22 NSCA Neg Obs LA.1
07/06/2022
501000064521
22 NSCA Neg Obs CL.4
07/06/2022
501000066665
D6 Dampers Found in Unexpected Position
09/25/2022
501000069398
Inverter Fan Not Working
2/21/2022
501000069662
2 Spent Fuel Pool Wide Range Level Indicator Locked Up
01/04/2023
501000070471
Inverter Fan Not Working
2/05/2023
20000004654
Apparent Cause Evaluation - Received Multiple Unexpected
Alarms
05/28/2019
71152B
Corrective Action
Documents
2000020940
Apparent Cause Evaluation - Comprehensive Pump Test
03/28/2022
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Was Not Performed After DDCLP Maintenance
Equipment Cause Evaluation for CRDM Cooling System
Trouble
04/22/2015
QIM
501000043114
MIC: Acceptable Thinning Detected
08/10/2020
QIM
501000070475
Calibrated Gauge, No As Found Data
2/06/2023
501000071987
04/05/2023
501000072023
Corrective Action Documentation Records
04/04/2023
501000072066
CV-31652 Nonconforming to IST Code
04/07/2023
501000072086
Potential Error in POD
04/06/2023
501000072095
CA Lacking Documentation
04/07/2023
501000072274
PI&R Response Longer than 24 Hours
04/13/2023
501000072453
CE for 11 Inverter Bypass
04/18/2023
501000072530
Light Bulb Change Procedure Improvement
04/19/2023
Corrective Action
Documents
Resulting from
Inspection
501000072531
Fan Impact on Inverter Operability
04/19/2023
NF-40301-1
WIRING DIAGRAM DC DISTRIBUTION PANELS "A" TRAIN
NF-40302-1
WIRING DIAGRAM AC DISTRIBUTION PANELS 111, 1111,
113, 1113, 115, 117 (A TRAIN)
NF-40624-1
EXTERNAL WIRING DIAGRAM RADIATION MONITORING
SYSTEM
X-HIAW-1001-
963(1)
Interconnecting Diagram NRP Plant Radiation Monitoring
System
E
X-HIAW-1001-
963-5
CONSOLE WIRING DIAGRAM CABINET NO. 1
XH-1001-963-11
CONSOLE WIRING DIAGRAM CABINET NO. II RADIATION
MONITORING SYSTEM
Drawings
XH-1001-963-6
WIRING DIAGRAM
Engineering
Changes
601000002441
Revise 11 and 12 MFW Stator Temp SPT
Nuclear Safety Culture Monitoring Panel Reports
01/2021 -
2/2022
Miscellaneous
CAP Screen Team Meeting
04/05/2023
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Prairie Island Pulse Survey Results
01/2023
Xcel Energy Nuclear Safety Culture Assessment
6/20-23/2022
610000001577
Operating Experience IR 2021004 Peach Bottom
04/13/2022
610000001578
Operating Experience IR 2021002 Calvert Cliffs
07/29/2022
610000001814
Operating Experience - Quad Cities White Finding SDP
2/15/2022
P8405L-047
Human Performance
FP-PA-EFR-01
Effectiveness Review Manual
SWI NE-22
Shuffle Works TM Fuel Movement Planning System
5AWI 15.5.1
Plant Equipment Control Process
C18.1
ENGINEERED SAFEGUARDS EQUIPMENT SUPPORT
SYSTEMS
FL-ESP-RXP-
2M
REFUELING/FUEL HANDLING ACTIVITIES (PWR)
FP-OP-OL-01
Operability
FP-OP-RSK-01
Risk Monitoring and Risk Management
FP-PA-ARP-01
CAP Process
FP-WM-IRM-01
Integrated Risk Management
FP-WM-MMP-01
Minor Maintenance Process
FP-WM-WOI-01
Work Identification, Screening, Validation, and Cancellation
Procedures
SP 1951
SPENT FUEL POOL ASSEMBLY VERIFICATION
606000001409
06/16/2022
606000001546
FSA: Problem Identification & Resolution at PINGP
09/19-
23/2022
Self-Assessments
606000001690
22 Ops HU/FUND/STAND Live Look
06/17/2022
00364879
REPLACE 2FT-925 SI F TO RCS COLD LEG XMTR DUE
TO DRIFT
07/06/2015
700093327
LARGE MTR/PMP THERMOGRAPHY INSP
06/09/2022
Work Orders
700101411
PM 4910-1 9-LARGE MTR/PMP THRMGPHY INSP
2/10/2023