Text

Integrated Inspection Report 05000298/2023001
	ML23101A121
Person / Time
Site:	Cooper
Issue date:	04/17/2023
From:	Jeffrey Josey; NRC/RGN-IV/DORS/PBC
To:	Dia K; Nebraska Public Power District (NPPD)
	Josey J
References
	IR 2023001
	Download: ML23101A121 (16)
	v • d • e

April 17, 2023

SUBJECT:

COOPER NUCLEAR STATION - INTEGRATED INSPECTION REPORT 05000298/2023001

Dear Khalil Dia:

On March 31, 2023, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Cooper Nuclear Station. On April 10, 2023, the NRC inspectors discussed the results of this inspection with John Dent and other members of your staff. The results of this inspection are documented in the enclosed report.

No findings or violations of more than minor significance were identified during this inspection.

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, Jeffrey E. Josey, Chief Projects Branch C Division of Operating Reactor Safety Docket No. 05000298 License No. DPR-46

Enclosure:

As stated

Inspection Report

Docket Number:

05000298

License Number:

DPR-46

Report Number:

05000298/2023001

Enterprise Identifier:

I-2023-001-0012

Licensee:

Nebraska Public Power District

Facility:

Cooper Nuclear Station

Location:

Brownville, NE

Inspection Dates:

January 1, 2023, to March 31, 2023

Inspectors:

K. Chambliss, Senior Resident Inspector

Approved By:

Jeffrey E. Josey, Chief

Projects Branch C

Division of Operating Reactor Safety

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at Cooper Nuclear 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

No findings or violations of more than minor significance were identified.

Additional Tracking Items

Type Issue Number Title Report Section Status LER 05000298/2022-003-00 Actuation of Reactor Protection System Initiates a Full Reactor Scram 71153 Closed

PLANT STATUS

Cooper Nuclear Station began the inspection period at rated thermal power. On February 10, 2023, power was lowered to approximately 60 percent for a planned rod pattern adjustment. The plant returned to rated thermal power on February 11, 2023.

The unit remained at rated thermal power for the remainder of the inspection period.

INSPECTION SCOPES

Inspections were conducted using the appropriate portions of the inspection procedures (IPs) in effect at the beginning of the inspection unless otherwise noted. Currently approved IPs with their attached revision histories are located on the public website at http://www.nrc.gov/reading-rm/doc-collections/insp-manual/inspection-procedure/index.html. Samples were declared complete when the IP requirements most appropriate to the inspection activity were met consistent with Inspection Manual Chapter (IMC) 2515, Light-Water Reactor Inspection Program - Operations Phase. The inspectors performed activities described in IMC 2515, Appendix D, Plant Status, observed risk significant activities, and completed on-site portions of IPs. The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel to assess licensee performance and compliance with Commission rules and regulations, license conditions, site procedures, and standards.

REACTOR SAFETY

71111.01 - Adverse Weather Protection

Impending Severe Weather Sample (IP Section 03.02) (2 Samples)

(1) The inspectors evaluated the adequacy of the overall preparations to protect risk-significant systems from impending severe weather during a winter weather advisory on January 23, 2023.

(2) The inspectors evaluated the adequacy of the overall preparations to protect risk-significant systems from impending severe weather during a winter storm warning on February 17, 2023.

71111.04 - Equipment Alignment

Partial Walkdown Sample (IP Section 03.01) (4 Samples)

The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:

(1)division 1 emergency diesel generator on January 11, 2023 (2)reactor equipment cooling subsystem A on February 2, 2023 (3)standby liquid control on February 22, 2023 (4)division 2 standby gas treatment on March 17, 2023

71111.05 - Fire Protection

Fire Area Walkdown and Inspection Sample (IP Section 03.01) (6 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)division 2 emergency diesel generator room, 917-foot 6-inch and 903-foot 6-inch elevations, on January 11, 2023 (2)fire pump building on January 23, 2023 (3)waste collector drain tank room on February 1, 2023 (4)intake structure, 903-feet 6-inch elevation, on February 10, 2023 (5)reactor building reactor equipment cooling area, 931-foot elevation, on February 22, 2023 (6)office building penthouse, 946-foot 11-inch elevation, on March 14, 2023

Fire Brigade Drill Performance Sample (IP Section 03.02) (1 Sample)

(1) The inspectors evaluated the onsite fire brigade training and performance during an unannounced fire drill on March 12, 2023.

71111.06 - Flood Protection Measures

Flooding Sample (IP Section 03.01) (1 Sample)

(1) The inspectors evaluated internal flooding mitigation protections in the reactor building northeast quadrant on January 13, 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) The inspectors observed and evaluated licensed operator performance in the control room during quarterly down power for core management on February 11, 2023.

Licensed Operator Requalification Training/Examinations (IP Section 03.02) (1 Sample)

(1) The inspectors observed and evaluated a simulator emergency preparedness scenario on January 13, 2023.

71111.12 - Maintenance Effectiveness

Maintenance Effectiveness (IP Section 03.01) (2 Samples)

The inspectors evaluated the effectiveness of maintenance to ensure the following structures, systems, and components (SSCs) remain capable of performing their intended function:

(1)residual heat removal function PF02B near (a)(1) on January 9, 2023 (2)high pressure coolant injection function PF01 at (a)(1) on March 6, 2023

71111.13 - Maintenance Risk Assessments and Emergent Work Control

Risk Assessment and Management Sample (IP Section 03.01) (4 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)planned Yellow online risk during emergency diesel generator 1 maintenance window on February 1, 2023 (2)planned Yellow online risk during 4160 V bus 1F undervoltage relay testing on February 8, 2023 (3)planned Yellow online risk during reactor core isolation cooling maintenance window on March 6, 2023 (4)planned Yellow online risk during high pressure coolant injection maintenance window on March 17, 2023

71111.15 - Operability Determinations and Functionality Assessments

Operability Determination or Functionality Assessment (IP Section 03.01) (4 Samples)

The inspectors evaluated the licensee's justifications and actions associated with the following operability determinations and functionality assessments:

(1)repeated alarms for control rod drive accumulator 34-35 on January 23, 2023 (2)safety relief valve B spline nuts not replaced as planned on February 17, 2023 (3)emergency station service transformer voltage below technical specification limits on February 17, 2023 (4)two control rods failed to fully withdraw on February 17, 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) (8 Samples)

(1)emergency diesel generator maintenance window post-maintenance test on February 22, 2023 (2)emergency service station transformer current transformer rewiring post maintenance test on March 13, 2023 (3)reactor core isolation cooling maintenance window post maintenance test on March 14, 2023 (4)reactor core isolation cooling turbine steam supply valve refurbishment and adjustment on March 31, 2023 (5)high pressure coolant injection hydraulic actuator replacement on March 31, 2023 (6)high pressure coolant injection turbine steam supply valve refurbishment and adjustment on March 31, 2023 (7)high pressure coolant injection 250 Vdc overload relay for injection valve replacement on March 31, 2023 (8)alternate shutdown panel emergency diesel generator 2 relay post maintenance testing on March 31, 2023

Surveillance Testing (IP Section 03.01) (3 Samples)

(1)division 2 main steam isolation valve channel logic test on January 24, 2023 (2)4160 V bus undervoltage relay channel functional test on February 8, 2023 (3)service water division 2 annual pump test on February 24, 2023

Inservice Testing (IST) (IP Section 03.01) (2 Samples)

(1)high pressure coolant injection quarterly pump vibration in-service test on January 25, 2023 (2)reactor equipment cooling biennial in-service test on January 31, 2023

71114.06 - Drill Evaluation

Select Emergency Preparedness Drills and/or Training for Observation (IP Section 03.01) (1 Sample)

(1)emergency preparedness drill on January 24,

OTHER ACTIVITIES - BASELINE

===71151 - Performance Indicator Verification The inspectors verified licensee performance indicators submittals listed below:

MS06: Emergency AC Power Systems (IP Section 02.05)===

Main article: IP 71151