IR 05000352/2023001

Integrated Inspection Report 05000352/2023001 and 05000353/2023001

ML23118A027
Person / Time
Site:	Limerick
Issue date:	04/28/2023
From:	Sarah Elkhiamy Division of Operating Reactors
To:	Rhoades D Constellation Energy Generation, Constellation Nuclear
References
IR 2023001
Download: ML23118A027 (1)

Text

April 28, 2023

SUBJECT:

LIMERICK GENERATING STATION, UNITS 1 AND 2 - INTEGRATED INSPECTION REPORT 05000352/2023001 AND 05000353/2023001

Dear David Rhoades:

On March 31, 2023, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Limerick Generating Station, Units 1 and 2. On April 17, 2023, the NRC inspectors discussed the results of this inspection with Michael Gillin, Site Vice President, 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, Sarah H. Elkhiamy, Chief Projects Branch 4 Division of Operating Reactor Safety

Docket Nos. 05000352 and 05000353 License Nos. NPF-39 and NPF-85

Enclosure:

As stated

Inspection Report

Docket Numbers:

05000352 and 05000353

License Numbers:

NPF-39 and NPF-85

Report Numbers:

05000352/2023001 and 05000353/2023001

Licensee:

Constellation Energy Generation, LLC

Facility:

Limerick Generating Station, Units 1 and 2

Location:

Sanatoga, PA

Inspection Dates:

January 1, 2023 to March 31, 2023

Inspectors:

A. Ziedonis, Senior Resident Inspector

L. Grimes, Resident Inspector

Approved By:

Sarah H. Elkhiamy, Chief

Projects Branch 4

Division of Operating Reactor Safety

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees

performance by conducting an integrated inspection at Limerick Generating Station, Units 1 and

2, 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

None.

PLANT STATUS

Unit 1 operated at or near rated thermal power for the entire inspection period.

Unit 2 began the inspection period at rated thermal power. On March 2, 2023, the unit entered a

planned end of cycle coastdown condition toward the end of the two-year operating cycle, which

resulted in a planned gradual slow reduction of thermal power. On March 18, 2023, the unit was

shutdown, from approximately 90 percent thermal power, for a maintenance outage to replace

the 'A' recirculation pump seal as a result of degraded conditions that were identified by the

licensee. The unit was returned to approximately 90 percent thermal power on

March 23, 2023, and continued in an end of cycle coastdown status 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 DProperty "Inspection Manual Chapter" (as page type) with input value "NRC Inspection Manual 2515,</br></br>Appendix D" contains invalid characters or is incomplete and therefore can cause unexpected results during a query or annotation process., Plant Status, observed risk significant activities, and completed on-site portions of

IPs. The inspectors reviewed selected procedures and records, observed activities, and

interviewed personnel to assess licensee performance and compliance with Commission rules

and regulations, license conditions, site procedures, and standards.

REACTOR SAFETY

71111.04 - Equipment Alignment

Partial Walkdown (IP Section 03.01) (3 Samples)

The inspectors evaluated system configurations during partial walkdowns of the following

systems/trains:

(1)

Unit 1 feedwater system during online noble chemistry injection during the week of

January 2, 2023

(2)

Unit 1 circulating water system following flooding in pump house lower level on

January 19, 2023

(3)

Unit 2 emergency diesel generator (EDG) D21 jacket water system on

January 23, 2023

71111.05 - Fire Protection

Fire Area Walkdown and Inspection (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)

Unit 1 fire area 37, 'D' core spray pump room on January 9, 2023

(2)

Unit 1 fire area 80, D13 EDG room and fuel oil and lube oil tank room on

January 17, 2023

(3)

Unit common fire outbuilding area, circulating water pump house on

January 20, 2023

(4)

Unit 2 fire area 57, high-pressure coolant injection (HPCI) pump room on

February 10, 2023

(5)

Unit 2 fire area 68, reactor building control rod drive equipment and neutron

monitoring areas on March 17, 2023

71111.06 - Flood Protection Measures

Flooding (IP Section 03.01) (1 Sample)

The inspectors evaluated internal flooding mitigation protections in the:

(1)

Unit 1 reactor building safeguards system access area rooms 200 and 304, and core

spray pump rooms on March 29, 2023

71111.07A - Heat Exchanger/Sink Performance

Annual Review (IP Section 03.01) (1 Sample)

The inspectors evaluated readiness and performance of:

(1)

Unit 1 'A' residual heat removal (RHR) heat exchanger heat transfer rate test on

January 31 and February 1, 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 a Unit 2 planned power reduction for the removal of 5B feedwater heater

from service on February 24, 2023; during a Unit 2 planned power reduction for the

removal of 5A and 5C feedwater heaters from service on March 1, 2023; during

shutdown for maintenance outage 2M57 on March 18, 2023; and during reactor

startup from 2M57 on March 22, 2023

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

(1)

The inspectors observed and evaluated licensed operator requalification training

scenarios in the simulator on February 13, 2023

71111.12 - Maintenance Effectiveness

Maintenance Effectiveness (IP Section 03.01) (1 Sample)

The inspectors evaluated the effectiveness of maintenance to ensure the following

structures, systems, and components remain capable of performing their intended function:

(1)

Unit 2 recirculation pump 'A' seal during the week of February 21, 2023

71111.13 - Maintenance Risk Assessments and Emergent Work Control

Risk Assessment and Management (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)

Unit 1 risk assessment and emergent work in response to a main generator exciter

cooling service water leak during the week of January 2, 2023

(2)

Unit 1 planned action green risk during HPCI maintenance on

January 9 and 10, 2023

(3)

Unit common emergent work in response to an unplanned trip of the 'A' main control

room chiller on March 17, 2023

(4)

Unit 2 elevated risk condition due to the drywell being de-inerted during reactor start-

up and plant heat-up on March 22, 2023

71111.15 - Operability Determinations and Functionality Assessments

Operability Determination or Functionality Assessment (IP Section 03.01) (5 Samples)

The inspectors evaluated the licensee's justifications and actions associated with the

following operability determinations and functionality assessments:

(1)

Unit common main control room envelope during corrective maintenance in support of

sewer line repairs during the week of January 9, 2023

(2)

Unit 1 HPCI system with non-functional barometric condenser vacuum pump during

the week of January 9, 2023

(3)

Unit 1 control rod position indication following loss of core display and 4-rod display

on March 10 and March 13, 2023

(4)

Unit 2 'C' source range monitor (SRM) following circuit wind-up condition on

March 20, 2023

(5)

Unit 2 HPCI steam admission motor-operated valve following NRC identification of

oil/grease separation on March 18 and 21, 2023

71111.18 - Plant Modifications

Temporary Modifications and/or Permanent Modifications (IP Section 03.01 and/or 03.02) (1 Sample)

The inspectors evaluated the following temporary or permanent modifications:

(1)

Unit 1 main generator air cooler mechanical line stop device installation following

discovery of a service water leak on January 24 and 25, 2023

71111.20 - Refueling and Other Outage Activities

Refueling/Other Outage (IP Section 03.01) (1 Sample)

(1)

The inspectors evaluated Unit 2 maintenance outage (2M57) activities from

March 18, 2023 through March 23, 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) (6 Samples)

(1)

Unit 1 HPCI pump, valve and flow test following planned maintenance on

January 10 and 11, 2023

(2)

Unit 2 'C' RHR pump, valve and flow test following planned maintenance on

January 20, 2023

(3)

Unit 1 D11 diesel generator slow start operability test run on February 28, 2023

(4)

Unit 2 'A' SRM following corrective maintenance on March 19, 2023

(5)

Unit 2 'D' inboard main steam isolation valve following packing replacement on

March 20, 2023

(6)

Unit 2 'A' recirculation pump seal following replacement on March 22, 2023

Surveillance Testing (IP Section 03.01) (2 Samples)

(1)

ST-6-049-230-1, Unit 1 reactor core isolation cooling (RCIC) pump, valve and flow

test on February 2 and 6, 2023

(2)

ST-6-049-230-1, Unit 2 RCIC pump, valve and flow test on February 15, 2023

Reactor Coolant System Leakage Detection Testing (IP Section 03.01) (1 Sample)

(1)

ST-6-107-590-2, Unit 2 reactor coolant system elevated unidentified leak rate during

the week of February 27, 2023

Diverse and Flexible Coping Strategies (FLEX) Testing (IP Section 03.02) (1 Sample)

(1)

'B' FLEX diesel generator functional test on January 18, 2023

71114.06 - Drill Evaluation

Drill/Training Evolution Observation (IP Section 03.02) (1 Sample)

The inspectors evaluated:

(1)

The inspectors observed and evaluated licensed operator requalification training

scenarios in the simulator on February 6, 2023

OTHER ACTIVITIES - BASELINE

71151 - Performance Indicator Verification

The inspectors verified licensee performance indicators submittals listed below:

IE03: Unplanned Power Changes per 7000 Critical Hours (IP Section 02.02) (2 Samples)

(1)

Unit 1 for the period of January 1, 2022 through December 31, 2022

(2)

Unit 2 for the period of January 1, 2022 through December 31, 2022

MS07: High-Pressure Injection Systems (IP Section 02.06) (2 Samples)

(1)

Unit 1 for the period of January 1, 2022 through December 31, 2022

(2)

Unit 2 for the period of January 1, 2022 through December 31, 2022

MS08: Heat Removal Systems (IP Section 02.07) (2 Samples)

(1)

Unit 1 for the period of January 1, 2022 through December 31, 2022

(2)

Unit 2 for the period of January 1, 2022 through December 31, 2022

INSPECTION RESULTS

No findings were identified.

EXIT MEETINGS AND DEBRIEFS

The inspectors verified no proprietary information was retained or documented in this report.

• On April 17, 2023, the inspectors presented the integrated inspection results to

Michael Gillin, Site Vice President, and other members of the licensee staff.

THIRD PARTY REVIEWS

Inspectors reviewed Institute on Nuclear Power Operations reports that were issued during the

inspection period.