Text

Comprehensive Engineering Team Inspection Report 05000482/2024014
	ML24341A034
Person / Time
Site:	Wolf Creek
Issue date:	12/17/2024
From:	Vincent Gaddy; NRC/RGN-IV/DORS/EB1
To:	Reasoner C; Wolf Creek
References
	IR 2024014
	Download: ML24341A034 (18)
	v • d • e

December 17, 2024

SUBJECT:

WOLF CREEK GENERATING STATION - COMPREHENSIVE ENGINEERING TEAM INSPECTION REPORT 05000482/2024014

Dear Cleve Reasoner:

On November 13, 2024, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Wolf Creek Generating Station and discussed the results of this inspection with Jamie McCoy, Site Vice President 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 and was determined to be Severity Level IV. 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 IV; the Director, Office of Enforcement; and the NRC Resident Inspector at Wolf Creek Generating Station.

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 IV; and the NRC Resident Inspector at Wolf Creek Generating Station. 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, Vincent G. Gaddy, Chief Engineering Branch 1 Division of Operating Reactor Safety Docket No. 05000482 License No. NPF-42

Enclosure:

As stated

Inspection Report

Docket Number:

05000482

License Number:

NPF-42

Report Number:

05000482/2024014

Enterprise Identifier:

I-2024-014-0002

Licensee:

Wolf Creek Nuclear Operating Corp.

Facility:

Wolf Creek Generating Station

Location:

Burlington, KS

Inspection Dates:

October 21, 2024, to November 13, 2024

Inspectors:

C. Baron, Contractor

D. Bryen, Reactor Inspector

W. Cullum, Senior Reactor Inspector

S. Graves, Senior Reactor Inspector

R. Kumana, Senior Reactor Inspector

D. Reinert, Senior Reactor Analyst

F. Thomas, Reactor Inspector

Approved By:

Vincent G. Gaddy, Chief

Engineering Branch 1

Division of Operating Reactor Safety

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting a comprehensive engineering team inspection at Wolf Creek Generating 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

Failure to Perform an Evaluation Pursuant to 10 CFR 50.59 for Adding Operator Actions to Mitigate a Chemical Volume and Control System (CVCS) Rupture Cornerstone Significance/Severity Cross-Cutting Aspect Report Section Mitigating Systems Green Severity Level IV NCV 05000482/2024014-01 Open/Closed

[H.4] -

Teamwork 71111.21M The inspectors identified a Green finding of 10 CFR 50, Appendix B, Criterion III, Design Control when the licensee added additional equipment, which was not previously relied upon, to mitigate a Chemical Volume and Control System (CVCS) rupture in the Auxiliary Building, and an associated Severity Level IV Non-cited Violation (NCV) of 10 CFR 50.59, Changes,

Tests, and Experiments, when the licensee did not perform a written evaluation which provides the bases for the determination that the change, test, or experiment does not require a license amendment pursuant to paragraph 50.59(c)(2).

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.

REACTOR SAFETY

===71111.21M - Comprehensive Engineering Team Inspection The inspectors evaluated the following components and listed applicable attributes, permanent modifications, and operating experience:

Structures, Systems, and Components (SSCs) (IP section 03.01)===

Main article: IP 71111.21

(1) NK44, 125VDC Panel DP-NK44

Updated Safety Analysis Report (USAR), technical specifications (TS), and TS bases document

Visual inspection of bus for as-built configuration and material condition

Environmental conditions

Short circuit and equipment protection

Load voltage

Component maintenance history

System Health Report

(2) EEJ01A, Residual Heat Removal Heat Exchanger 1A

Residual heat removal system piping and instrumentation diagram

Vendor manual for installation, operation, and maintenance of the heat exchanger

System operating procedures

Corrective action program documents

Visual inspection of the as-built configuration and material condition

(3) EJFCV0618, Residual Heat Removal Heat Exchanger Bypass Valve 618

Calculations for required thrust, actuator capability, and available margin

Valve and actuator vendor manuals for installation, operation, and

maintenance

Inservice and diagnostic testing records including procedures and results for position

Indication and stroke time testing

Maintenance work order history records of visual inspections, lubrications, and elastomer replacement

Corrective action program documents

Visual inspection of the as-built configuration and material condition (4)480V Bus NG01/Transformer XNG01

Updated final safety analysis report, technical specifications, and technical specifications bases document.

Electrical drawings

Component maintenance history and corrective action program documents

Procedures for transformer inspection, maintenance, and testing

Voltage analysis and short circuit calculations

Visual inspection of switchgear for as-built configuration and material condition

Environmental conditions for equipment

System health report

Vendor manual and plant design drawings

(5) EFHV0051, Train A Component Cooling Water Heat Exchanger Essential Service Water Inlet Valve

Piping and instrumentation drawings

Vendor documentation

Calculations for torque and thrust

Visual inspection of the component

Corrective actions related to the component

Preventative maintenance history

System operating procedures and emergency operation

(6) SGL10A, Residual Heat Removal Room Cooler

Piping and instrumentation drawings

Room heat load calculations

Tube plugging limit calculation

Vendor documentation

Visual inspection of the component

Corrective actions related to the component

Preventative maintenance history

(7) Essential Service Water Train B HVAC Fan CGD01B

Design requirements within purchase specifications

Functionality tests of the essential service water pumphouse ventilation system

Room heat load calculations

Component maintenance history and corrective action program reports

Essential service water pumphouse ventilation system piping and instrumentation diagram

Vendor manual for installation, operation, and maintenance of the essential service water pumphouse ventilation fans

Visual inspection of the as-built configuration and material condition

(8) NK13, 125VDC Battery

Updated Safety Analysis Report (USAR), technical specifications (TS), and TS bases document

Visual inspection of battery cells, support structure, conductors, and material condition

Environmental conditions

Maintenance and testing history

Cell temperature calculation

System Health Report

Evaluation of Operator Actions to Locally Align Swing Charger (OPA-NK025)

(9) AFW Motor-Driven Pump, PAL01B

Pump Head and Flow Requirements

NPSH Requirements

Minimum Recirculation Flow Requirements

Basis for Inservice Testing Acceptance Criteria

Evaluation of Recent Inservice Testing Results

Evaluation of Limiting Runout Flow Conditions

Evaluation of Operator Actions to Terminate Flow to Faulted Steam Generator (OPA-SLB)

Testing Requirements for Manual Valves Credited with Isolating Flow

Evaluation of Seismic Hazards in AF Pump Room

Evaluation of Automatic Transfer of Pump Suction from CST to ESW

(10) Condensate Storage Tank, TAP01

Evaluation of Tanks Capacity Requirements

Evaluation of Protection of Tank from External Hazards

Evaluation of Freeze Protection of Tank and Associated Piping

Evaluation of Level Setpoints for Automatic Transfer of AF Pumps and Alarms

Evaluation of Tank Floating Barrier and Associated Vents

Modifications (IP section 03.02) (5 Samples)

(1) Change Package 20007, 7300 Controls Upgrade - Protection Set

(2) Change Package 20500, Component Cooling Water Heat Exchanger EEG01A Pitting Repair

(3) Change Package 20394, Emergency Diesel Generator Jacket Water Bleeder Vent Valves

(4) Change Package 14726, AKR-30 Battery Charger Supply Breaker Setting Changes

(5) Change Package 20082, Replace Check Valves ALV0030 and ALV0042 with New Design 10 CFR 50.59 Evaluations/Screening (IP section 03.03) (20 Samples)

(1) GS-M-005, Aluminum in Containment

(2) GS-M-006, Zinc in Containment

(3) CP 20734, Replacement of Post Accident PR/SR Recorder with Yokogawa

(4) AN-07-009, GOTHIC Model for Component Cooling Water Pump Room Temperature

(5) GK-M-014, Cooling and Heating Load Calculation Control Building Class 1E Electrical Equipment Areas During Accident Conditions - Train A

(6) SYS-EP-200, Safety Injection Accumulator Operation

(7) YY-49, High Energy Line Break in the Auxiliary Building (8)

===020663, Main Feedwater Regulating Valve Body to Bonnet Stud Repair (9)020616, BBPV8702B Motor rotor change - magnesium to aluminum (10)020631, System Descriptions M-10B and M-10EN Update

(11) STS KJ-005B, Manual/Auto Start Sync & Loading of EDG NE02 (12)020535.11.01-C-035, Essential Service Water System Train B Room Coolers - Auxiliary Building (P-287 Parts 2 - 6)

(13)020292, Substation Transformers No. 8,9,10 & 11 and Breakers Replacement R25 (14)020538, PFSSD Modification to Address IN 92-18 for Multiple 'A' Train MOVS-Refuel (15)020551, Cyber Security Equipment Upgrade (16)020671, Containment WI-FI Upgrade

(17) XX-M-070, FAC Program Minimum Wall Thickness Calculation for Small Bore Piping and Components

(18) AL-16-W, Determine the Available NPSH for the Auxiliary Feedwater Pumps, with Dissolved Nitrogen in the Condensate Storage Tank

(19) CP 020624, TDAFW Sprinkler Main Drain Addition

(20) EMG E-0 REV. 48, EMG Procedure Revision Screen Operating Experience Samples (IP section 03.04)===

Main article: IP 02066

(1) CR 10017549, IRIS Event 475377 Callaway Emergency Exhaust Fan

(2) CR 10015425, Part 21 on NPS Part Number 16-AAT907B, 48 VDC Power Supplies

(3) CR 10020756, RCP ESBU-TB-91-04 Revision in M-712-00202

INSPECTION RESULTS

Failure to Perform an Evaluation Pursuant to 10 CFR 50.59 for Adding Operator Actions to Mitigate a Chemical Volume and Control System (CVCS) Rupture Cornerstone Significance/Severity Cross-Cutting Aspect Report Section Mitigating Systems Green Severity Level IV NCV 05000482/2024014-01 Open/Closed

[H.4] -

Teamwork 71111.21M The inspectors identified a Green finding of 10 CFR 50, Appendix B, Criterion III, Design Control when the licensee added additional equipment, which was not previously relied upon, to mitigate a Chemical Volume and Control System (CVCS) rupture in the Auxiliary Building, and an associated Severity Level IV Non-cited Violation (NCV) of 10 CFR 50.59, Changes, Tests, and Experiments, when the licensee did not perform a written evaluation which provides the bases for the determination that the change, test, or experiment does not require a license amendment pursuant to paragraph 50.59(c)(2).

Description:

The inspectors reviewed a change to calculation YY-49, High Energy Line Breaks in the Auxiliary Building, and the associated 10CFR50.59 screening. The calculation change resulted in a reduction in time for time-critical operator actions that were already in place to isolate the rupture, and an addition of new time-sensitive operator actions required to mitigate a rupture in the Chemical Volume and Control System (CVCS) in the Auxiliary Building. The new operator actions were associated with initiating the Emergency Exhaust System (EES) within one hour to improve the atmospheric conditions in the Auxiliary Building.

Procedure AI 21-016, Operator Time Critical Actions Validation, which included the reduction in time to isolate the CVCS rupture and the new time sensitive actions to initiate EES, was released prematurely on 3/15/2022 before the change to calculation YY-49 was issued. The 50.59 screening for the change to calculation YY-49 was performed on 6/1/2022.

Since the procedure change to AI 21-016 was already issued which established the new operator actions, the plant staff performing the 50.59 review did not realize that new operator actions were being established since they already appeared in the procedure. As a result, the 50.59 review incorrectly established that the change to calculation YY-49 screened out and a 50.59 evaluation was not performed.

Corrective Actions: The licensee entered the issue into the corrective action program.

Corrective Action References: CR 10037557

Performance Assessment:

Performance Deficiency: The licensee failed to establish measures that assure the design basis is correctly translated in specifications, drawings, and procedures as required by 10 CFR 50, Appendix B, Criterion III, Design Control. Specifically, the licensee issued a procedure change notice prior to a formal design change which resulted in additional operator actions during a CVCS rupture.

Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Design Control 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 licensee added manual actions to initiate the Emergency Exhaust System (EES) within one hour following a Chemical Volume and Control System (CVCS) rupture. There was no technical evaluation for these additional operator actions or the use of EES following a CVCS rupture. The EES was previously not relied upon for the mitigation of a CVCS rupture.

Significance: The inspectors assessed the significance of the finding using IMC 0609 Appendix A, The Significance Determination Process (SDP) for Findings At-Power.

Inspectors used Exhibit 2, Mitigating Systems Screening Questions, to evaluate the significance. The finding screened to Green because the finding is a deficiency affecting the design or qualification of a mitigating SSC, and the SSC maintained its operability or PRA functionality. Specifically, the new time sensitive operator actions were validated and the operability of the EES was not called into question.

Cross-Cutting Aspect: H.4 - Teamwork: Individuals and work groups communicate and coordinate their activities within and across organizational boundaries to ensure nuclear safety is maintained. The inspectors determined that the performance deficiency was reflective of current performance since the issue occurred within the nominal three year period. The cross-cutting aspect of Teamwork was chosen because there was a breakdown in communication between the individual who issued the procedure change ahead of the revision to the calculation.

Enforcement:

The ROPs significance determination process does not specifically consider the regulatory process impact in its assessment of licensee performance. Therefore, it is necessary to address this violation which impedes the NRCs ability to regulate using traditional enforcement to adequately deter non-compliance.

Severity: The inspectors used guidance in Enforcement Manual Section 2.1.3, Enforcement of 10 CFR 50.59 and Related FSAR Violations, along with Enforcement Policy Section 6.1, and Enforcement Manual Appendix E, Examples of Minor Violations. Inspectors determined that the significance of the issue is consistent with Severity Level IV. Specifically, the associated finding screened as Very Low Safety Significance using the Significance Determination Process.

Violation: Title 10 of the Code of Federal Regulations Part 50.59(d)(1) states that, The licensee shall maintain records of changes in the facility, of changes in procedures, and of tests and experiments made pursuant to 50.59(c). These records must include a written evaluation which provides the bases for the determination that the change, test, or experiment does not require a license amendment pursuant to 50.59(c)(2).

Contrary to this requirement, from August 22, 2022 to November 13, 2024, the licensee did not include a written evaluation which provides the bases for the determination that the change, test, or written experiment does not require a license amendment pursuant to 50.59(c)(2). Specifically, the licensee did not perform an evaluation for the addition of a time sensitive operator action to operate the EES within one hour following a CVCS rupture in the Auxiliary Building. The EES is a system that was not previously relied upon to mitigate this event.

Title 10 of the Code of Federal Regulations Part 50, Appendix B, Criterion III, Design Control, requires in part that, Measures shall be established that assure the design basis is correctly translated in specifications, drawings, and procedures.

Contrary to this requirement, the licensee did not establish measures to assure that the design basis is correctly translated in specification, drawings, and procedures. Specifically, the licensee released a procedure change which incorporated new operator actions prior to a change in calculation that required those additional operator actions.

Enforcement Action: This violation is being treated as a non-cited violation, 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 November 13, 2024, the inspectors presented the comprehensive engineering team inspection results to Jamie McCoy, Site Vice President and other members of the licensee staff.

DOCUMENTS REVIEWED

Inspection

Procedure

Type

Designation

Description or Title

Revision or

Date

v t e Inspection Report - Wolf Creek - 2024014
80 \| 81 \| 82 \| 83 \| 84 \| 85 \| 86 \| 87 \| 88 \| 89 \| 90 \| 91 \| 92 \| 93 \| 94 \| 95 \| 96 \| 97 \| 98 \| 99 00 \| 01 \| 02 \| 03 \| 04 \| 05 \| 06 \| 07 \| 08 \| 09 \| 10 \| 11 \| 12 \| 13 \| 14 \| 15 \| 16 \| 17 \| 18 \| 19 \| 20 \| 21 \| 22 \| 23 \| 24 \| 25 \| 26 \|
2024 Quarterly Integrated 1Q (0) 2Q (0) 3Q (0) 4Q (0) Assessments Mid Cycle End of Cycle 10(0) 12(0) 14(0) Security 401(0) 402(0) 420(0) Operator Exams 301(0) Emergency Planning Other

IR 05000482/2024014