IR 05000416/2021001

GG2021001-IR-TS, Grand Gulf Nuclear Station - Integrated Inspection Report 05000416/2021001

ML21123A300
Person / Time
Site:	Grand Gulf
Issue date:	05/05/2021
From:	Jason Kozal NRC/RGN-IV/DRP
To:	Franssen R Entergy Operations
References
IR 2021001
Download: ML21123A300 (24)

Text

May 5, 2021

SUBJECT:

GRAND GULF NUCLEAR STATION - INTEGRATED INSPECTION REPORT 05000416/2021001

Dear Mr. Franssen:

On March 31, 2021, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Grand Gulf Nuclear Station. On April 15, 2021, the NRC inspectors 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.

Two findings of very low safety significance (Green) are documented in this report. Both findings involved violations of NRC requirements. We are treating these violations as non-cited violations (NCVs) consistent with Section 2.3.2 of the Enforcement Policy.

If you contest the violations or the significance of the violations 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 Grand Gulf Nuclear 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 Grand Gulf Nuclear 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 (10 CFR) 2.390, Public Inspections, Exemptions, Requests for Withholding.

Sincerely, Jason W. Digitally signed by Jason W. Kozal Kozal Date: 2021.05.05 09:06:34 -05'00'

Jason W. Kozal, Chief Reactor Projects Branch C Division of Reactor Projects Docket No. 05000416 License No. NPF-29

Enclosure:

As stated

Inspection Report

Docket Number: 05000416 License Number: NPF-29 Report Number: 05000416/2021001 Enterprise Identifier: I-2021-001-0087 Licensee: Entergy Operations, Inc.

Facility: Grand Gulf Nuclear Station Location: Port Gibson, MS Inspection Dates: January 1, 2021, to March 31, 2021 Inspectors: R. Alexander, Senior Emergency Preparedness Inspector D. Antonangeli, Health Physicist J. Braisted, Reactor Inspector A. Donley, Project Engineer N. Greene, Senior Health Physicist R. Lanfear, Physical Security Specialist T. Steadham, Senior Resident Inspector M. Thomas, Resident Inspector Approved By: Jason W. Kozal, Chief Reactor Projects Branch C Division of Reactor Projects Enclosure

SUMMARY

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

Failure to Follow Procedures and Maintain Doses ALARA for a Work Activity Cornerstone Significance Cross-Cutting Report Aspect Section Occupational Green [H.5] - Work 71124.02 Radiation Safety NCV 05000416/2021001-01 Management Open/Closed The inspectors identified a Green, non-cited violation of Technical Specification 5.4.1 for the licensees failure to follow radiation protection procedures, resulting in not maintaining doses as low as reasonably achievable (ALARA) for work activities involving the rebuild of main steam isolation valve 1B21F022A. The final accrued dose exceeded the revised dose estimate by more than 50 percent, with an actual accrued dose of greater than 5 person-Rem.

Failure to Ensure Functionality of Drywell Unidentified Leakage Monitoring System Cornerstone Significance Cross-Cutting Report Aspect Section Initiating Events Green [P.2] - 71152 NCV 05000416/2021001-02 Evaluation Open/Closed The inspectors identified a Green finding and associated non-cited violation of Technical Specification 3.4.7 when the licensee failed to ensure that the drywell air cooler condensate flow rate monitoring system could perform its intended function. Specifically, on December 21, 2020, and January 7, 2021, flow obstructions prevented the system from being capable of performing its intended function.

Additional Tracking Items

None.

PLANT STATUS

Grand Gulf Nuclear Station, Unit 1, began the inspection period at rated thermal power. On January 8, 2021, the unit was down powered to 75 percent in order to secure a feedwater heater drain tank valve leak. The unit was returned to rated thermal power on January 10, 2021. On January 30, 2021, the unit was down powered to 60 percent to conduct a control rod sequence exchange. The unit was returned to rated thermal power later that day.

The unit remained at or near 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 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.

Starting on March 20, 2020, in response to the National Emergency declared by the President of the United States on the public health risks of the Coronavirus Disease 2019 (COVID-19),resident inspectors were directed to begin telework and to remotely access licensee information using available technology. During this time, the resident inspectors performed periodic site visits each week; conducted plant status activities as described in IMC 2515, Appendix D, Plant Status; observed risk-significant activities; and completed on-site portions of IPs. In addition, resident and regional baseline inspections were evaluated to determine if all or portions of the objectives and requirements stated in the IP could be performed remotely. If the inspections could be performed remotely, they were conducted per the applicable IP. In some cases, portions of an IP were completed remotely and on-site. The inspections documented below met the objectives and requirements for completion of the IP.

71111.01 - Adverse Weather Protection

Impending Severe Weather Sample (IP Section 03.02) (1 Sample)

(1) The inspectors evaluated the adequacy of the overall preparations to protect risk-significant systems from winter storm impending severe weather on January 10, 2021.

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) Low pressure core spray walkdown following maintenance on February 3, 2021

(2) Division 2 emergency diesel generator on February 2, 2021

(3) Division 1 emergency diesel generator while the Division 2 emergency diesel generator was out of service for maintenance on March 10, 2021

(4) Division 1 control room air conditioning while Division 2 was tagged out of service for maintenance on March 10, 2021

Complete Walkdown Sample (IP Section 03.02) (1 Sample)

(1) The inspectors evaluated system configurations during a complete walkdown of the drywell unidentified leakage monitoring system on March 1, 2021.

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) Division 1 emergency diesel generator, Fire Zone 1D310 on January 21, 2021

(2) Low pressure core spray pump room, Fire Zone 1A119, on February 3, 2021

(3) Division 1 control building heating, ventilation, and air conditioning room, Fire Zone OC302, on February 12, 2021

(4) Division 2 control building heating, ventilation, and air conditioning room, Fire Zone OC303, on February 17, 2021

(5) Division 1 switchgear room, Fire Zone OC202, on March 18, 2021

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

(1) The inspectors evaluated the onsite fire brigade training and performance during an announced fire drill on March 10, 2021.

71111.06 - Flood Protection Measures

Inspection Activities - Internal Flooding (IP Section 03.01) (1 Sample)

The inspectors evaluated internal flooding mitigation protections in the:

(1) Division 1 residual heat removal pump room on February 26, 2021

71111.07A - Heat Sink Performance

Annual Review (IP Section 03.01) (1 Sample)

The inspectors evaluated readiness and performance of:

(1) Low pressure core spray pump room cooler cleaning and testing on March 25, 2021

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) Main steam isolation valve maintenance on March 24, 2021

(2) System T51, emergency core cooling room coolers on March 25, 2021

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) Drywell leakage monitoring system on March 1, 2021

71111.13 - Maintenance Risk Assessments and Emergent Work Control

Risk Assessment and Management Sample (IP Section 03.01) (6 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) Risk management during Division 2 work window on January 25, 2021

(2) Risk management during Division 1 work week on February 26, 2021

(3) Risk management on March 9, 2021, while standby fresh air B was tagged out for maintenance on March 10, 2021

(4) Yellow risk management while the Division 2 emergency diesel generator was out of service on March 8, 2021

(5) Risk management during work on protected equipment (spent fuel pool cooling system) on March 11, 2021

(6) Maintenance risk management during Division 2 emergency diesel generator operability concerns on March 18, 2021

71111.15 - Operability Determinations and Functionality Assessments

Operability Determination or Functionality Assessment (IP Section 03.01) (7 Samples)

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

(1) Condition Report CR-GGNS-2021-00318, Division 2 emergency diesel generator engine crankcase pressure switch found out of tolerance on February 11, 2021

(2) Condition Report CR-GGNS-2021-00469, Division 2 emergency diesel generator left bank turbo gasket deficiency on February 17, 2021

(3) Condition Report CR-GGNS-2021-00529, environmental qualification of ring terminals on February 26, 2021

(4) Condition Report CR-GGNS-2021-00271, operability of drywell cooler condensate drain line monitoring instruments on February 12, 2021

(5) Condition Report CR-GGNS-2021-01801, Division 1 emergency diesel generator jacket water pipe hanger found with unsecured locking fastener on March 18, 2021

(6) Condition Report CR-GGNS-2021-01175, crimp tool failed as-found calibration on March 24, 2021

(7) Condition Report CR-GGNS-2021-01923, Z51-F073A standby service water to control room air conditioning condenser A had evidence of a leak on March 31, 2021

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) Technical Specification 5.4.7 bases change on March 24, 2021

71111.19 - Post-Maintenance Testing

Post-Maintenance Test Sample (IP Section 03.01) (4 Samples)

The inspectors evaluated the following post-maintenance test activities to verify system operability and functionality:

(1) Work Order 538764, replace Division 2 emergency diesel generator governor oil on February 11, 2021

(2) Work Order 52954348, post maintenance test on the control room air conditioning B system following maintenance on March 12, 2021

(3) Work Order 542110, replace cable splices for 1B21F022C, inboard main steam isolation valve C on March 24, 2021

(4) Work Order 52923654, perform acid flush of 1T51B002, low pressure core spray room cooler on March 25, 2021

71111.22 - Surveillance Testing

The inspectors evaluated the following surveillance tests:

Surveillance Tests (other) (IP Section 03.01)

(1) Work Order 52962731-01, Procedure 06-IC-1P45-M-0001 drywell floor drain sump level switch surveillance on March 11, 2021

Inservice Testing (IP Section 03.01) (1 Sample)

(1) Work Order 52961348-01, Procedure 06-OP-1C41-Q-0001 standby liquid control pump B functional test on March 2, 2021

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

(1) Increased unidentified drywell leakage on February 11, 2021

FLEX Testing (IP Section 03.02) (1 Sample)

(1) Flex pump B annual testing on February 1, 2021

71114.01 - Exercise Evaluation

Inspection Review (IP Section 02.01-02.11) (1 Partial)

(1) (Partial)

The inspectors evaluated the biennial emergency plan exercise conducted on March 16, 2021. However, as of the end of the 1st Quarter 2021, the licensee had not completed its critique process for the exercise. As such, the inspectors had not completed the full evaluation of the exercise and the critique process. The inspectors will complete the inspection in the 2nd Quarter, and the results of the inspection will be documented in NRC Inspection Report 05000416/2021002.

71114.08 - Exercise Evaluation Scenario Review

Inspection Review (IP Section 02.01 - 02.04) (1 Sample)

(1) The inspectors reviewed the licensee's preliminary exercise scenario that was submitted to the NRC on January 14, 2021 (ADAMS Accession No. ML21014A192)for the exercise scheduled to occur on March 16, 2021. The inspectors discussed the preliminary scenario with Mr. M. Lewis, Manager, Emergency Preparedness, and other members of the emergency preparedness staff on February 11, 2021. The inspectors' review does not constitute NRC approval of the scenario.

71124.02 - Occupational ALARA Planning and Controls

Radiological Work Planning (IP Section 03.01) (4 Samples)

The inspectors evaluated the licensees radiological work planning. The inspectors evaluated the following work activities:

(1) RWP 2020-1519, rebuild 1B21F022A and support work

(2) RWP 2020-1801, install feedwater debris strainers

(3) RWP 2020-1517, 1G33F250 valve work

(4) RWP 2020-1523, 1B33F067A recirculation pump discharge valve work and support Verification of Dose Estimates and Exposure Tracking Systems (IP Section 03.02) (4 Samples)

The inspectors evaluated dose estimates and exposure tracking. The inspectors reviewed the following ALARA planning documents:

(1) RWP 2020-1531, RF-22 diving (suppression pool)

(2) RWP 2020-1800, turbine control system (EHC) upgrade

(3) RWP 2020-1915, emergent work for maintenance, tours, and inspections (Normal and Low Risk Only)

(4) RWP 2020-1073, reactor water cleanup heat exchanger room steam leak

71124.04 - Occupational Dose Assessment

Source Term Characterization (IP Section 03.01) (1 Sample)

(1) The inspectors evaluated licensee performance as it pertains to radioactive source term characterization.

External Dosimetry (IP Section 03.02) (1 Sample)

(1) The inspectors evaluated licensee performance as it pertains to external dosimetry that is used to assign occupational dose, including issuance, use, and storage of dosimetry.

Internal Dosimetry (IP Section 03.03) (1 Sample)

The inspectors evaluated the internal dosimetry program implementation.

(1) The inspectors reviewed the following:

Whole Body Counts

• 18-03-180245

• 19-07-020146

• 19-07-020734

• 20-03-201432 In-Vitro Internal Monitoring

• Work Order 503946 - Bioassay for Contaminated Divers, 02/14/2020 Dose Assessments Performed Using Air Sampling and Derived Air Concentration-Hour Monitoring

• None were available during this inspection

Special Dosimetric Situations (IP Section 03.04) (3 Samples)

The inspectors evaluated the following special dosimetric situation:

(1) Licensees implementation of requirements to manage radiation protection of 12 declared pregnant workers

(2) EDEX dose assessment and redacted NRC Form 5 for six individuals using multipack dosimetry

(3) Neutron dose tracking forms for workers in a neutron source field

OTHER ACTIVITIES - BASELINE

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

EP01: Drill/Exercise Performance (IP Section 03.12) ===

(1) October 1, 2020, through December 31, 2020

IE01: Unplanned Scrams per 7000 Critical Hours Sample (IP Section 03.01) (1 Sample)

(1) January 1, 2020, through December 31, 2020

EP02: ERO Drill Participation (IP Section 03.13) (1 Sample)

(1) October 1, 2020, through December 31, 2020

EP03: Alert & Notification System Reliability (IP Section 03.14) (1 Sample)

(1) October 1, 2020, through December 31, 2020

BI01: Reactor Coolant System Specific Activity Sample (IP Section 03.10) (1 Sample)

(1) January 1, 2020, through December 31, 2020

BI02: RCS Leak Rate Sample (IP Section 03.11) (1 Sample)

(1) January 1, 2020, through December 31, 2020

71152 - Problem Identification and Resolution

Annual Follow-up of Selected Issues (IP Section 02.03) (1 Sample)

The inspectors reviewed the licensees implementation of its corrective action program related to the following issues:

(1) Condition Report CR-GGNS-2020-09741, drywell condensate drain line flow meter reading downscale on March 26, 2021

71153 - Followup of Events and Notices of Enforcement Discretion Event Followup (IP Section 03.01)

(1) The inspectors evaluated the notification of unusual event due to high drywell leakage and the licensee's response on January 11,

INSPECTION RESULTS

Failure to Follow Procedures and Maintain Doses ALARA for a Work Activity Cornerstone Significance Cross-Cutting Report Aspect Section Occupational Green [H.5] - Work 71124.02 Radiation Safety NCV 05000416/2021001-01 Management Open/Closed The inspectors identified a Green, non-cited violation of Technical Specification 5.4.1 for the licensees failure to follow radiation protection procedures, resulting in not maintaining doses as low as reasonably achievable for work activities involving the rebuild of main steam isolation valve 1B21F022A. The final accrued dose exceeded the revised dose estimate by more than 50 percent, with an actual accrued dose of greater than 5 person-Rem.

Description:

During Refueling Outage 22, the work activity to rebuild main steam isolation valve (MSIV) 1B21F022A and support work required two additional rebuilds to correctly fix the valve stem. On April 15, 2020, after the initially scheduled work, the MSIV A failed its local leak rate test (LLRT), and upon investigation its valve stem was deemed scored. Due to the failed LLRT, the licensee determined the need to conduct a discovery rebuild of the MSIV A. After the first additional rebuild, the valve again failed its LLRT, and the new valve was found scored again after the test. The licensee identified that the valve bonnet was out of tolerance, which was then corrected during a second additional rebuild, resulting in passing the LLRT. It is noteworthy to mention that the licensees mechanical group experienced similar issues with scoring of the valve stem in 2012 but did not review or consider these lessons learned during the planning process for this work activity. Thus, the as low as reasonably achievable planning group did not include this operating experience aspect in the job scope, resulting in poor work management for the job.

An apparent cause evaluation was conducted by the licensee after completion of this job to determine the contributing factors in the causes of these multiple LLRT failures and rebuilds performed on this valve. The first contributing cause identified was that the valve bonnets were installed incorrectly because they were supplied out of tolerance, and the licensee failed to verify the tolerances of the poppets after machining the seating surfaces. Additionally, the licensee used a hot shop lathe during the troubleshooting process relative to the poppets being nonconcentric after machining, and also used liquid graphite versus the vendor-recommended blue check dye during the LLRT, which all contributed to the challenges with this job. Lastly, the instructions in the work order for inspection of the machined parts differed from the vendor recommended method, which resulted in out of tolerance machined parts passing inspections and being properly installed. The licensee requested assistance from the vendor, who helped identify the issues and assisted in the final rebuild of the MSIV. All these factors could be considered foreseeable and preventable.

The licensees post job review of the work activity package included statements that acknowledged the preventable failures in the planning process of this job:

• The valve failed post maintenance LLRT. This was the opportunity for the station to pull back into a strategic questioning attitude/approach.

• This confirms, with a high degree of certainty, the legacy aspect on these MSIV stem issues were the result of the bonnet tolerances.

• After all facts (through the CR-GGNS-2020-05234 B-ACA evaluation) about the work history were determined, it was identified that the station missed the opportunity for a strategical approach to planned 1B21F022A MSIV work scope.

Procedure EN-RP-100, ALARA Program, Section 4.0[7], states, in part, review maintenance and modification packages to verify lessons learned and other exposure saving ideas are incorporated into work packages thereby continuously improving job plans.

Section 4.0[8] of Procedure EN-RP-100, states, in part, that personnel responsibilities include, minimizing the potential for unnecessary exposure due to poor communications or lack of proper planning/scheduling.

Thus, the inspectors concluded that there were missed opportunities for the licensee to correctly scope, manage, and effectively plan the job. Specifically, MSIV A had a history going back to April 2012 that involved issues with scoring of the valve stem, indicating that a comprehensive approach to this valve work would have been beneficial.

These additional MSIV A rebuilds caused the initial dose projection of 2.777 person-Rem for the work activity to be revised two times to 8.013 person-Rem. The actual accrued dose to workers was 10.239 person-Rem. After a detailed review of the work activity, the NRC determined the revised dose estimate should not have exceeded 6.111 person-Rem. As a result, the NRC determined the actual accrued dose was more than 50 percent (i.e.

68 percent) of the justified revised dose estimate.

Corrective Actions: The licensee evaluated the work activity in a post-job review document, in which they addressed the issues discussed in this write-up. Thus, the licensee documented the issue into their corrective action program, conducted an apparent cause evaluation, and evaluated their work orders.

Corrective Action References: Condition Report CR-GGNS-2020-05234

Performance Assessment:

Performance Deficiency: The licensee failed to follow their ALARA planning procedures and did not properly plan the scope of work activities involving the MSIV A 1B21F022A rebuild.

Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Program and Process attribute of the Occupational Radiation Safety cornerstone and adversely affected the cornerstone objective to ensure the adequate protection of the worker health and safety from exposure to radiation from radioactive material during routine civilian nuclear reactor operation. Additionally, the finding was similar to Example 6(i) in Appendix E to Inspection Manual Chapter 0612, Power Reactor Inspection Reports - Examples of Minor Issues. This example states that an issue is more than minor if it results in a collective dose greater than 5 person-Rem, and the actual dose accrued exceeds the estimated dose by greater than 50 percent. In this case, the actual dose exceeded the revised dose estimate, as determined by the NRC, by nearly 68 percent.

Significance: The inspectors assessed the significance of the finding using Inspection Manual Chapter 0609 Appendix C, Occupational Radiation Safety SDP. The inspectors determined the finding had very low safety significance (Green) because:

(1) it was associated with ALARA planning and work controls; and

(2) the licensees latest 3-year rolling average collective dose was less than 240 person-Rem.

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 failed to properly plan the work activity by not reviewing available operating experience, lessons learned, and vendor recommendations, and not considering risks associated with proceeding with alternate parts and materials for the LLRT, resulting in multiple failures.

Enforcement:

Violation: Technical Specification 5.4.1 requires, in part, that written procedures shall be established, implemented, and maintained covering the procedures recommended in Regulatory Guide 1.33, Appendix A, Revision 2, dated February 1978. Section 7(e) of Appendix A requires radiation protection procedures. Licensee Procedure EN-RP-110, ALARA Program, described the responsibilities for outage planning/working groups and supervisory personnel, which included review maintenance and modification packages to verify lessons learned and other exposure saving ideas are incorporated into work packages thereby continuously improving job plans, as well as, minimizing the potential for unnecessary exposure due to poor communications or lack of proper planning/scheduling.

Contrary to the above, on April 15, 2020, the licensee failed to review maintenance and modification packages to verify lessons learned and other exposure saving ideas are incorporated into work packages thereby continuously improving job plans, which resulted in not minimizing the potential for unnecessary exposure due to the lack of proper planning/scheduling. Specifically, the licensee failed to incorporate all available information into the work packages that would help avoid equipment errors and help minimize occupational dose for the work activity by accounting for past operating experience of a scored MSIV valve stem and reviewing vendor recommendations for proper installation and testing of parts. This resulted in multiple reworks of the job and not maintaining doses ALARA for workers.

Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.

Failure to Ensure Functionality of Drywell Unidentified Leakage Monitoring System Cornerstone Significance Cross-Cutting Report Aspect Section Initiating Events Green [P.2] - 71152 NCV 05000416/2021001-02 Evaluation Open/Closed The inspectors identified a Green finding and associated non-cited violation of Technical Specification 3.4.7 when the licensee failed to ensure that the drywell air cooler condensate flow rate monitoring system could perform its intended function. Specifically, on December 21, 2020, and January 7, 2021, flow obstructions prevented the system from being capable of performing its intended function.

Description:

On September 12, 2020, operators identified that recorder 1E31R609, a drywell cooler condensate drain line flow recorder, was reading downscale. Operators declared the associated system inoperable and entered Technical Specification (TS) Action Statement 3.4.7.C.1, which required a channel check of the drywell particulate and airborne radioactivity monitors to be performed at least once every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. This issue was documented in Condition Report CR-GGNS-2020-09741 as a suspected line blockage based on site operating experience.

On October 28, 2020, after performing a channel check and other observations of the system, operations personnel declared the system to be operable and exited TS 3.4.7.C.1. During a subsequent forced outage, technicians flushed the drywell cooler condensate drain line under Work Order 550987 and identified some sludge and a lot of algae in the line. Technicians continued to flush the line until it ran clear.

On December 21, 2020, operators identified a step change increase in drywell unidentified leakage rate from an average of approximately 0.10 gallon per minute (gpm) to 2.93 gpm, which slowly began trending back down to normal. The issue was entered into the corrective action program as Condition Report CR-GGNS-2020-12316. Operators determined that no degraded or nonconforming condition existed, and the licensee closed the condition report with no specific actions taken because, it alone [did] not represent a condition requiring correction within the corrective action process.

On January 7, 2021, unidentified leakage increased from a nominal 0.13 gpm to approximately 16 gpm and remained elevated for over 15 minutes. Operators declared a Notification of Unusual Event but did not identify any reactor or containment parameters indicative of a reactor coolant system leak. The inspectors independent assessment concurred with the licensees in that the cause was most likely that an obstruction in the drywell cooler condensate drain line system had become dislodged, allowing approximately 220 gallons of water to enter the drywell floor sump in a relatively short period of time.

With an obstruction in the system, water was allowed to accumulate in the drain line portion of the system, thereby creating a hold-up volume. This would have rendered the system incapable of detecting a 1 gpm leak, as any additional leakage would have accumulated in the hold-up volume until such time as the obstruction cleared itself due to the static height of water or the volume filled completely and overflowed allowing a different unidentified leakage monitoring system to detect the leak.

The licensee initially considered the drywell cooler condensate drain line flow monitoring system to be operable after the obstruction cleared. The inspectors were concerned that there was no objective evidence that the obstruction had been completely removed from the system and that the mechanism that allowed the obstruction to develop likely remained present, as there were no corrective actions to address the condition. Further, as discussed in Updated Final Safety Analysis Report (UFSAR), Section 7.6.2.4.2.1, the system design basis was to monitor for unidentified leakage with a sensitivity of detecting a 1 gpm leak within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. The inspectors were concerned that with at least three recent cases of obstructions in the system and the uncertainty of whether an obstruction still existed, there was reasonable doubt of whether the system could perform its intended function of detecting a leak of at least 1 gpm. After discussions with the licensee, operators declared the drywell cooler condensate drain line flow monitoring system inoperable on January 22, 2021, and entered TS Action Statement 3.4.7.C.1.

Corrective Actions: Licensee corrective actions included declaring the system inoperable, entering the applicable TS action statement, and developing corrective actions for long term modifications of the system to increase equipment reliability and availability.

Corrective Action References: This issue was entered into the licensees corrective action program as Condition Report CR-GGNS-2021-00133.

Performance Assessment:

Performance Deficiency: The failure to ensure that the drywell air cooler condensate flow rate monitoring system was capable of performing its intended function is 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 Initiating Events cornerstone and adversely affected the cornerstone objective to limit the likelihood of events that upset plant stability and challenge critical safety functions during shutdown as well as power operations. Specifically, the performance deficiency contributed to the inoperability of the system.

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. Because the inspectors answered no to all screening questions in Exhibit 1, the finding screened to very low safety significance (Green).

Cross-Cutting Aspect: P.2 - Evaluation: The organization thoroughly evaluates issues to ensure that resolutions address causes and extent of conditions commensurate with their safety significance. Specifically, the licensee failed to adequately evaluate previous instances of obstructions/clogs in the system.

Enforcement:

Violation: As required by Technical Specification 3.4.7.C.1, with the drywell air cooler condensate flow rate monitoring system inoperable, a channel check of the required drywell atmospheric monitoring system is required once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. If this action is not performed, TS 3.4.7.F requires that the Unit be placed in Mode 3 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and Mode 4 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.

Contrary to the above, from December 21, 2020, through January 22, 2021,with the drywell air cooler condensate flow rate monitoring system inoperable, the licensee failed to perform a channel check of the drywell atmospheric monitoring system once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, and the licensee failed to place the Unit in Mode 3 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> of not performing the required channel check.

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 February 4, 2021, the inspectors presented the radiation safety inspection results to Mr. R. Franssen, Site Vice President, and other members of the licensee staff.

• On March 18, 2021, the inspectors presented the performance indicator verification inspection (portion of EP Exercise) results to Mr. M. Lewis, Emergency Preparedness Manager, and other members of the licensee staff.

• On April 15, 2021, the inspectors presented the integrated inspection results to Mr. R. Franssen, Site Vice President, and other members of the licensee staff.

DOCUMENTS REVIEWED

Inspection Type Designation Description or Title Revision or

Procedure Date

71111.04 Corrective Action CR-GGNS- 2021-01801, 2021-01923

Documents

71111.04 Drawings GFIG-OPS-Z5100 Control Room HVAC System (Z51) Figures 4

71111.04 Drawings M-0049 P & I Diagram Control Room HVAC System 32

71111.04 Drawings M-1070B Standby Diesel Generator System Unit 1 39

71111.04 Drawings M-1070D Standby Diesel Generation System 19

71111.04 Drawings M-1087 Low Pressure Core Spray System 35

71111.04 Drawings SFD-1087 System Flow Diagram Low Pressure Core Spray System 4

71111.04 Procedures 04-1-01-E21-1 Low Pressure Core Spray System 46

71111.04 Procedures 04-1-01-P75-1 Standby Diesel Generator System 114

71111.04 Procedures 04-1-02-1H22- Panel No: 1H22-P400 118

P400

71111.04 Procedures 04-S-01-Z51-1 Control Room HVAC System 59

71111.04 Procedures GGNS-CS-16 Structural Operability Criteria for Pipe Supports 0

71111.04 Procedures GGNS-M-300.2 Design Specification for Pipe Hangers, Supports, Restraints, 20

and Anchors

71111.04 Procedures GGNS-M-300.6 Installation of Nuclear Service Pipe Supports 30

71111.04 Procedures PS-S-002 Pipe Support Operability Standard 1

71111.05 Corrective Action CR-GGNS- 2021-00612, 2021-01922

Documents

71111.05 Fire Plans A-10 Pre-Plan 2

71111.05 Fire Plans C-03 Pre-Plan, Division I SWGR Area and Battery Room 4

71111.05 Fire Plans DG-02 Pre-Plan 6

71111.05 Miscellaneous Section UFSAR - Fire Zone 1A119: LPCS Room, Elev. 93'0"

9A.5.3.4.d

71111.05 Miscellaneous Section 9A.5.61 UFSAR

71111.05 Procedures EN-DC-330 Fire Protection Program 7

71111.07A Corrective Action CR-GGNS- 2021-00748, 2021-00842, 2021-01141, 2021-02295

Documents

71111.07A Work Orders WO 557193, 52923654

71111.12 Corrective Action CR-GGNS- 2021-01141, 2021-02146, 2021-02147

Documents

Inspection Type Designation Description or Title Revision or

Procedure Date

71111.12 Miscellaneous Maintenance Rule Expert Panel Meeting Minutes 03/10/2021

71111.12 Work Orders WO 539705, 542110

71111.13 Procedures 07-S-53-G46-28 Fuel Pool Backwash Tank Level 8

71111.13 Procedures EN-OP-119 Protected Equipment Postings 13

71111.15 Corrective Action CR-GGNS- 2017-10799, 2021-00271, 2021-00318-CA-01, 2021-00469,

Documents 2021-00529, 2021-01175, 2021-01633, 2021-01635, 2021-

01656, 2021-01736, 2021-01801, 2021-01923, 2021-02146,

21-02160, 2021-02199

71111.15 Drawings GGNS-CS-16 Structural Operability Criteria for Pipe Supports 0

71111.15 Drawings GGNS-M-300.2 Design Specification for Pipe Hangers, Supports, Restraints, 20

and Anchors

71111.15 Drawings GGNS-M-300.6 Installation of Nuclear Service Pipe Supports 30

71111.15 Drawings M-0049 Control Room HVAC System 47

71111.15 Drawings M-1061C Standby Service Water System 38

71111.15 Drawings PS-S-002 Pipe Support Operability Standard 1

71111.15 Engineering EC-79383 Markup to Calculation MC-Q1P41-11001 to Include Moderate 0

Changes Energy Line Break of a Division of SSW

71111.15 Miscellaneous EQDP-EQ22.2 Environmental Qualification File for AMP Terminal and Splice 2

71111.15 Procedures 04-S-01-Z51-1 Control Room HVAC System 59

71111.15 Procedures MC-Q1P41-03016 Standby Service Water Maximum Allowable Post-LOCA 3

System Leakage

71111.15 Procedures MC-Q1P41-11001 GGNS Standby Service Water Ultimate Heat Sink Thirty Day 0

Performance at EPU

71111.15 Work Orders WO 465516, 465517, 511824, 511826, 520220, 520222, 527791,

27792, 539705, 540568, 542110, 542737, 52601795,

2602396

71111.18 Miscellaneous 2011-068 Licensing Basis Design Change Request dated October 5,

2011

71111.19 Corrective Action CR-GGNS- 2021-00842, 2021-02147

Documents

71111.19 Procedures EN-OP-102 Protective and Caution Tagging 24

71111.19 Work Orders WO 538764, 542110, 52923654, 52954348

71111.22 Corrective Action CR-GGNS- 2021-01697

Documents

Inspection Type Designation Description or Title Revision or

Procedure Date

71111.22 Miscellaneous Chemistry Drywell Atmosphere Sample Results from Elevated

Drywell Readings seen in December 2020

71111.22 Miscellaneous Reactor Coolant Isotopic Filter and Filtrate Chemistry Sample

Results from December 2020 and January 6, 2021

71111.22 Miscellaneous Containment Sump Chemistry and Radioactivity Results

71111.22 Miscellaneous CEP-IST-1 Inservice Testing Bases Document 316

71111.22 Miscellaneous CEP-IST-2 Inservice Testing Plan 320

71111.22 Miscellaneous CEP-IST-3 Inservice Testing Cross Reference Document 316

71111.22 Miscellaneous CEP-IST-4 Standard on Inservice Testing 309

71111.22 Miscellaneous DR-ECH-EN-OP-

109

71111.22 Miscellaneous SEP-GGNS-IST-1 GGNS Inservice Testing Bases Document 7

71111.22 Miscellaneous SEP-GGNS-IST-2 GGNS Inservice Testing Plan 9

71111.22 Procedures 06-IC-1P45-M- Drywell Floor Drain Sump Level Switch Functional Test 110

0001

71111.22 Procedures 06-OP-1C41-Q- Standby Liquid Control Functional Test 130

0001

71111.22 Procedures EN-DC-332 Inservice Testing Duties and Responsibilities 3

71111.22 Procedures EN-MA-157 Maintenance Configuration Control 4

71111.22 Work Orders WO 52916477, 52961348-01, 52962731

71114.01 Corrective Action CR-GGNS- 2017-03208, 2017-03213, 2017-03223, 2017-03230, 2017-

Documents 03233, 2017-03307, 2017-03312, 2017-03400, 2019-02074,

2019-02075, 2019-02190, 2019-02376, 2019-02378, 2019-

2419, 2019-02494, 2019-04502, 2019-05235, 2019-07102,

2019-07105, 2019-07133, 2019-08685, 2019-08772, 2019-

08773, 2019-09376, 2020-05531, 2020-07609, 2020-09467,

20-09773, 2020-10239, 2020-10942, 2020-10945, 2020-

10970, 2020-10971, 2020-10979, 2020-10991, 2020-11324,

20-11325, 2021-01480

71114.01 Miscellaneous GGNS 2021 Ingestion Pathway Exercise Manual 03/15/2021

71114.01 Miscellaneous GGNS Exercise Participant Logs - EOF, TSC, OSC, Control 03/16/2021

Room, Offsite Radiation Teams, and EOF Dose Assessor

71114.01 Miscellaneous GGNS HH2 Exercise Participant Logs - TSC and OSC 03/17/2021

71114.01 Miscellaneous 2021-3-17 GGNS HH2 Exercise Manual 03/15/2021

Inspection Type Designation Description or Title Revision or

Procedure Date

71114.01 Procedures EN-EP-609 Emergency Operations Facility (EOF) Operations 6

71114.01 Procedures EN-EP-610 Technical Support Center (TSC) Operations 5

71114.01 Procedures EN-EP-611 Operations Support Center (OSC) Operations 6

71114.01 Self-Assessments QA-7-2020- Emergency Preparedness 03/31/2020

GGNS-1

71124.02 Corrective Action CR-GGNS- 2020-02693, 2020-04017, 2020-04183, 2020-04962, 2020-

Documents 05787, 2020-07170, 2020-08618, 2020-09126, 2020-11508,

20-11510

71124.02 Procedures EN-RP-105 Radiation Work Permits 19

71124.02 Procedures EN-RP-110 ALARA Program 14

71124.02 Procedures EN-RP-110-01 ALARA Initiative Deferrals 1

71124.02 Procedures EN-RP-110-03 Collective Radiation Exposure Reduction Guidelines 4

71124.02 Procedures EN-RP-110-04 Radiation Protection Risk Assessment Process 8

71124.02 Procedures EN-RP-110-06 Outage Dose Estimating and Tracking 1

71124.02 Radiation Work RWP 2020-1073 RWCU HX Steam Leak 0

Permits (RWPs)

71124.02 Radiation Work RWP 2020-1517 1G33F250 Valve Work 0

Permits (RWPs)

71124.02 Radiation Work RWP 2020-1519 Rebuild 1B21F022A and Support Work 2

Permits (RWPs)

71124.02 Radiation Work RWP 2020-1531 RF-22 Diving (Suppression Pool) 4

Permits (RWPs)

71124.02 Radiation Work RWP 2020-1532 1B33F067A Recirc Pump Discharge Valve Work and Support 1

Permits (RWPs)

71124.02 Radiation Work RWP 2020-1800 Turbine Control System (EHC) Upgrade 3

Permits (RWPs)

71124.02 Radiation Work RWP 2020-1801 Install Feedwater Debris Strainers 1

Permits (RWPs)

71124.02 Radiation Work RWP 2020-1915 Emergent Work for Maintenance, Tours, and Inspections 5

Permits (RWPs) (Normal and Low Risk Only)

71124.02 Self-Assessments Pre-NRC Inspection: Occupational ALARA Planning and 11/23/2020

Control Assessment

71124.04 Corrective Action CR-GGNS- 2019-04670, 2019-07317, 2019-07751, 2019-07830, 2020-

Documents 01178, 2020-02505, 2020-05199, 2020-11672, 2020-11673,

Inspection Type Designation Description or Title Revision or

Procedure Date

HQN-2020-00505

71124.04 Miscellaneous EDEX Multipack Dosimetry - Compartmental Dose Value for 01/27/2021

Six Individuals

71124.04 Miscellaneous Environmental Dosimetry Company Annual Quality Assurance 03/25/2020

Report

71124.04 Miscellaneous 100518-0 NVLAP Certificate of Accreditation to ISO/IEC 17025:2017 - 01/01/2021

Landauer Inc. - Ionizing Radiation Dosimetry

71124.04 Miscellaneous 19-07-20146 Dose Investigation Report 05/15/2019

71124.04 Miscellaneous 19-07-20734 Dose Investigation Report 07/18/2019

71124.04 Miscellaneous 2019/2020 Dosimeter of Legal Record that Exceeded the 25% Differential 02/02/2021

for 2019-2020

71124.04 Miscellaneous Attachment 7.1 Grand Gulf Nuclear Power Station 5-Year Exposure Reduction 0

Plan 2021-2025

71124.04 Miscellaneous ENTERGY-066 Proposal for Neutron Dosimetry Evaluation, Rev. 02 01/06/2021

71124.04 Miscellaneous GGN-RPT-20- GEM-5 Passive Monitor Sensitivity Tests 04/02/2020

001-R1

71124.04 Miscellaneous GGN-RPT-20- Background Determination of DLRs Taken Home in the Area 04/13/2020

2-R0 Surrounding GGNS (DLR to SRD)

71124.04 Miscellaneous GIN-2020-00226 2020-2022 10CFR61 Waste Stream Analysis for Dry Active 12/17/2020

Waste (DAW)

71124.04 Miscellaneous NRC Form 5 Occupational Dose Record for a Monitoring Period (for six 2019-2020

individuals)

71124.04 Procedures EN-RP-131 Air Sampling 17

71124.04 Procedures EN-RP-152 Conduct of Radiation Protection 6

71124.04 Procedures EN-RP-201 Dosimetry Administration 5

71124.04 Procedures EN-RP-203 Dose Assessment 10

71124.04 Procedures EN-RP-204-01 Effective Dose Equivalent (EDEX) Monitoring 3

71124.04 Procedures EN-RP-206 Dosimeter of Legal Record Quality Assurance 7

71124.04 Procedures EN-RP-208 Whole Body Counting / In-Vitro Bioassay 7

71124.04 Procedures EN-RP-210 Area Monitoring Program 1

71124.04 Procedures EN-RP-317-09 Calibration of Dosimeters 5

71124.04 Radiation Surveys GGN-2102-00013 Dosimetry 02/02/2021

71124.04 Self-Assessments LO-GLO-2019- Pre-NRC Inspection Occupational Dose Assessment 11/22/2020

Inspection Type Designation Description or Title Revision or

Procedure Date

00186

71124.04 Self-Assessments QA-14-15-2019- Combined RP and Radwaste (RW) Audit 10/21/2019

GGNS-1

71124.04 Work Orders WO 503946 Bioassay for Contaminated Divers 02/14/2020

71151 Corrective Action CR-GGNS- 2021-00024, 2021-00884, 2021-00956, 2021-01087, 2021-

Documents 01525

71151 Miscellaneous DEP PI Evaluation Reports for LORQ Scenario GSES-LOR- 10/05/2020,

2019 CPE02 10/12/2020

71151 Miscellaneous Key ERO Participation Roster & Qualification Records 10/2020 -

2/2020

71151 Miscellaneous GIN 2020-00171 Alert Notification System Test - October 2020 10/27/2020

71151 Miscellaneous GIN 2020-00206 GGNS October 28, 2020 Blue Team 4th Quarter Drill Report 11/27/2020

71151 Miscellaneous GIN 2020-0190 Alert Notification System Test - November 2020 11/17/2020

71151 Miscellaneous GIN 2020-0196 Alert Notification System Test - December 2020 12/16/2020

71151 Procedures 01-S-10-3 Emergency Planning Department Responsibilities 24

71151 Procedures EN-FAP-EP-005 Emergency Preparedness Performance Indicators 14

71151 Procedures EN-LI-114 Regulatory Performance Indicator Process 17

71152 Corrective Action CR-GGNS- 2020-09741, 2020-11212, 2020-11213, 2020-11214, 2021-

Documents 00083, 2021-00133, 2021-00271

71152 Miscellaneous LCOTR 1-TS-20- Technical Specification

243

71153 Miscellaneous Informs Event Message Nos. 1 through 3

71153 Miscellaneous Drywell Fission Product Monitor Sample Result from 010721

0430

71153 Miscellaneous 55056 Event Notification 71153 Miscellaneous EN-EP-310, ERO Notification System Activation Instructions

71153 Miscellaneous EPP01-01 Emergency Director's Checklist (Control Room)

21