IR 05000269/2019003

Integrated Inspection Report 05000269/2019003, 05000270/2019003, 05000287/2019003, and 07200004/2019002

ML19311C347
Person / Time
Site:	Oconee, 07000004
Issue date:	11/07/2019
From:	Frank Ehrhardt NRC/RGN-II/DRP/RPB1
To:	Burchfield J Duke Energy Carolinas
J. Worosilo, RGN-II/DRP/RPB1
References
IR 2019003
Download: ML19311C347 (25)

Text

{{#Wiki_filter:ber 7, 2019

SUBJECT:

OCONEE NUCLEAR STATION - INTEGRATED INSPECTION REPORT 05000269/2019003, 05000270/2019003, 05000287/2019003, AND 07200004/2019002

Dear Mr. Burchfield,

Jr.: On September 30, 2019, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Oconee Nuclear Station. On October 21, 2019, 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.

One finding of very low safety significance (Green) is documented in this report. This finding involved a violation of NRC requirements. One Severity Level IV violation without an associated finding is documented in this report. 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 significance or severity 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 II; the Director, Office of Enforcement; and the NRC Resident Inspector at Oconee.

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 II; and the NRC Resident Inspector at Oconee.

J. Burchfield, Jr. 2 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 10 CFR 2.390, Public Inspections, Exemptions, Requests for Withholding.

Sincerely, /RA/ Frank J. Ehrhardt, Chief Reactor Projects Branch 1 Division of Reactor Projects Docket Nos. 50-269, 50-270, 50-287, 72-004 License Nos. DPR-38, DPR-47, DPR-55, SNM-2503

Enclosure:

IR 05000269/2019003, 05000270/2019003, 05000287/2019003, and 07200004/2019002

Inspection Report

Docket Numbers: 50-269, 50-270, 50-287, 72-004 License Numbers: DPR-38, DPR-47, DPR-55, SNM-2503 Report Numbers: 05000269/2019003, 05000270/2019003, 05000287/2019003, 07200004/2019002 Enterprise Identifier: I-2019-003-0022, I-2019-002-0084 Licensee: Duke Energy Carolinas, LLC Facility: Oconee Nuclear Station Location: Seneca, SC Inspection Dates: July 01, 2019 to September 30, 2019 Inspectors: J. Nadel, Senior Resident Inspector J. Parent, Resident Inspector A. Ruh, Resident Inspector A. Thomas, Acting Resident Inspector C. Fontana, Emergency Preparedness Inspector G. Hutto, Senior Resident Inspector (McGuire) S. Sanchez, Senior Emergency Preparedness Inspector J. Tornow, Physical Security Inspector J. Walker, Emergency Preparedness Inspector Approved By: Frank J. Ehrhardt, Chief Reactor Projects Branch 1 Division of Reactor Projects Enclosure

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at Oconee 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 Inadequate Control of Heavy Load in Spent Fuel Pool Cornerstone Significance Cross-Cutting Report Aspect Section Barrier Integrity Green [H.4] - 71111.13 NCV 05000287/2019003-01 Teamwork Open/Closed Inspectors identified a Green finding and associated non-cited violation (NCV) of Technical Specification (TS) 5.4.1, Procedures, when the licensee failed to properly pre-plan and control a heavy load lift in the Unit 3 spent fuel pool.

Failure to Notify the NRC within Eight Hours following the Discovery of a Condition that could have Prevented the Fulfillment of the Unit 1 Core Flood Systems Safety Function Cornerstone Significance Cross-Cutting Report Aspect Section Not Applicable NCV 05000269/2019003-02 Not Applicable 71111.15 Open/Closed The inspectors identified a Severity Level (SL) IV NCV of 10 CFR 50.72(b)(3)(v) when the licensee failed to notify the NRC within eight hours following the discovery of a condition that could have prevented the fulfillment of a safety function. Specifically, the Unit 1 core flood system, which is a system needed to mitigate the consequences of an accident, was inoperable because the Unit 1A core flood tank vent valve, 1CF-5, failed to close during a normal venting evolution.

Additional Tracking Items Type Issue Number Title Report Section Status LER 05000269/2019-001-00 LER 2019-001-00 for 71153 Closed Oconee Nuclear Station, Unit 1, Standby Shutdown Facility Reactor Coolant Makeup Pump Oil Suction Tubing Failure.

PLANT STATUS

Unit 1 operated at or near 100 percent rated thermal power (RTP) for the entire inspection period.

Unit 2 operated at or near 100 percent RTP for the entire inspection period.

Unit 3 operated at or near 100 percent RTP for the entire 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 plant status activities described in IMC 2515 Appendix D, Plant Status and conducted routine reviews using IP 71152, Problem Identification and Resolution. 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.

71111.01 - Adverse Weather Protection External Flooding Sample (IP Section 03.04)

(1) The inspectors evaluated readiness to cope with external flooding for the following areas:

• Standby shutdown facility (SSF) and the auxiliary, turbine, and service buildings regarding maintenance of a 6-inch water sill and resolution of nonconforming conditions in Nuclear Condition Report (NCR) 1905081.

71111.04Q - Equipment Alignment Partial Walkdown Sample (IP Section 03.01)

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

(1) SSF alignment during dual Keowee Hydro Unit Outage on July 16-17, 2019

(2) Unit 3 "A" train high pressure injection (HPI) system, on August 6, 2019

(3) 230kV Switch Yard Battery #2 alignment following service test & recharge on August 14, 2019

71111.04S - Equipment Alignment Complete Walkdown Sample (IP Section 03.02)

(1) Inspectors evaluated system configuration during a complete walkdown of the Unit 1 turbine driven emergency feedwater system, with additional in-office review.

71111.05Q - Fire Protection Quarterly Inspection (IP Section 03.01)

The inspectors evaluated fire protection program implementation in the following selected areas:

(1) Unit 2 auxiliary building Elevation 838', Fire Zone 117 on August 1, 2019

(2) Unit 3 auxiliary building Elevation 822', Fire Zone 112 on August 1, 2019

(3) Unit 1 auxiliary building Elevation 822', Fire Zone 110 on August 2, 2019

(4) Unit 1 and 2 auxiliary building Elevation 838', Fire Zone 119 on August 2, 2019

==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 Units 1, 2, and 3 turbine stop valve testing, on August 8, 2019.

Licensed Operator Requalification Training/Examinations (IP Section 03.02)==

(1) The inspectors observed and evaluated licensed operators perform a requal simulator exercise which involved a 1A reactor building cooling unit cooler rupture, 1A2 reactor coolant pump high vibration, delta Tc failure,1CC-8 failed closed causing a reactor trip, station blackout, and turbine driven emergency feedwater pump failure to auto start, on August 27, 2019.

71111.12 - Maintenance Effectiveness Routine Maintenance Effectiveness Inspection (IP Section 02.01)

The inspectors evaluated the effectiveness of routine maintenance activities associated with the following equipment and/or safety significant functions:

(1) NCR 2272633, 230kV Yellow Bus CCVTs failed Doble testing and were taken out of service for repair

71111.13 - Maintenance Risk Assessments and Emergent Work Control Risk Assessment and Management Sample (IP Section 03.01)

The inspectors evaluated the risk assessments for the following planned and emergent work activities:

(1) Risk assessment and work controls for July 16-17, 2019, during a dual Keowee Hydro Unit Outage

(2) Risk assessment and work controls for July 19, 2019, during CT-1 Open Phase Protection Mod tie-in

(3) Risk assessment and work controls for rigging a heavy load (3SF-2 valve) across the spent fuel pool on August 20, 2019

(4) Risk assessment and work controls for August 20-21, 2019, during an SSF outage to perform maintenance on CCW-289

71111.15 - Operability Determinations and Functionality Assessments Operability Determination or Functionality Assessment (IP Section 02.02)

The inspectors evaluated the following operability determinations and functionality assessments:

(1) Immediate determination of operability (IDO) for NCR 2280231, Unit 1 low pressure service water operability with pinhole leak downstream of 1LPSW-356

(2) IDO of the SSF standby battery system for a seismic event with temporary equipment (battery charger) staged adjacent to battery and its structural supports

(3) IDO for NCR 2285443, Unit 1 protected service water (PSW) piping following NRC identification of potential seismic interaction concern with unsecured door

(4) IDO for NCR 2286307, 3B low pressure service water (LPSW) pump min flow line degraded due to partial blockage and use of manual bypass valve

(5) IDO for NCR 2283504, Unit 1A Core Flood Tank following failure of 1CF-5 vent valve

(6) IDO for NCR 02283825, SSF Diesel Fuel Oil Tank Inspection Issue

(7) IDO for NCR 2282444, KPF-9 breaker closed unexpectedly when 86E lockout relay was reset

==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) Changes to bases for TS 3.7.10 allowing an underground Keowee hydro unit to be credited for protected service water operability

71111.19 - Post-Maintenance Testing Post-Maintenance Test Sample (IP Section 03.01)

[[IP sample::=

=IP 71111.18|count=6}}

The inspectors evaluated the following post maintenance tests:

(1) Work Order (WO) 20340144-01, testing of modified switch for 2LWD-1 containment isolation valve on July 11, 2019

(2) WO 20173119-05, Unit 3 HPI flow transmitter FT0007A replacement post-maintenance test (PMT) on July 29, 2019

(3) PT/2/A/0600/013, "Motor Driven Emergency Feedwater Pump Test," on August 7, 2019

(4) PT/0/A/0400/005, "SSF Auxiliary Service Water Pump Test," on August 24, 2019

(5) PT/1/A/0261/010, "Essential Siphon Vacuum System Test," on August 26, 2019

(6) WO 20329003, testing of 1PSW-24 valve following replacement of valve positioner board on September 4, 2019

71111.22 - Surveillance Testing The inspectors evaluated the following surveillance tests: Surveillance Tests (other) (IP Section 03.01)

(1) WO 20249209-01, PT/0/A/0620/016, Keowee Hydro Emergency Start Test on, July 9, 2019

Inservice Testing (IP Section 03.01) (2 Samples)

(1) PT/3/A/0203/006 A, Low Pressure Injection Pump Test - Recirculation on the 3B Low Pressure Injection Pump on July 3, 2019

(2) PT/3/A/0251/001, Low Pressure Service Water Pump Test on the 3B LPSW Pump on

August 11, 2019 FLEX Testing (IP Section 03.02) (1 Sample)

(1) WO 20325326, U0 Flex Equipment: Perform Functional Test and Inspection on July 22, 2019

71114.02 - Alert and Notification System Testing Inspection Review (IP Section 02.01-02.04)

(1) The inspectors evaluated the maintenance and testing of the alert and notification system during the week of September 16, 2019.

71114.03 - Emergency Response Organization Staffing and Augmentation System Inspection Review (IP Section 02.01-02.02)

(1) The inspectors evaluated the readiness of the Emergency Response Organization during the week of September 16, 2019.

71114.04 - Emergency Action Level and Emergency Plan Changes Inspection Review (IP Section 02.01-02.03)

(1) The inspectors evaluated submitted Emergency Action Level, Emergency Plan, and Emergency Plan Implementing Procedure changes during the week of September 16, 2019. This evaluation does not constitute NRC approval.

71114.05 - Maintenance of Emergency Preparedness Inspection Review (IP Section 02.01 - 02.11)

(1) The inspectors evaluated the maintenance of the emergency preparedness program during the week of September 16, 2019.

==71114.06 - Drill Evaluation Select Emergency Preparedness Drills and/or Training for Observation (IP Section 03.01) (1 Sample)

(1) Inspectors observed an emergency preparedness drill on July 17, 2019, that involved a faulted steam generator with a tube leak and damaged fuel. There was also a fuel handling accident in the spent fuel pool and a fire brigade response due to smoke coming from the Keowee hydro main step-up transformer.

OTHER ACTIVITIES - BASELINE

===71151 - Performance Indicator Verification The inspectors verified licensee performance indicators submittals listed below: EP01: Drill/Exercise Performance (IP Section 02.12)==

(1) Drill & Exercise Performance for the period July 1, 2018, through June 30, 2019.

EP02: ERO Drill Participation (IP Section 02.13) ===

(1) Emergency Response Organization Drill Participation for the period July 1, 2018, through June 30, 2019.

EP03: Alert & Notification System Reliability (IP Section 02.14) (1 Sample)

(1) Alert & Notification System Reliability for the period July 1, 2018, through June 30, 2019.

MS05: Safety System Functional Failures (SSFFs) Sample (IP Section 02.04) (3 Samples)

(1) Unit 1 (July 1, 2018 - June 30, 2019)

(2) Unit 2 (July 1, 2018, June 30, 2019)

(3) Unit 3 (July 1, 2018 - June 30, 2019)

MS08: Heat Removal Systems (IP Section 02.07) (3 Samples)

(1) Unit 1 (July 1, 2018 - June 30, 2019)

(2) Unit 2 (July 1, 2018 - June 30, 2019)

(3) Unit 3 (July 1, 2018 - June30, 2019)

BI01: Reactor Coolant System (RCS) Specific Activity Sample (IP Section 02.10) (3 Samples)

(1) Unit 1 (July 1, 2018 - June 30, 2019)

(2) Unit 2 (July 1, 2018 - June 30, 2019)

(3) Unit 3 (July 1, 2018 - June 30, 2019)

71152 - Problem Identification and Resolution Annual Follow-up of Selected Issues (IP Section 02.03)

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

(1) NCR 2270635 - Resolution of NRC identified problem regarding conflicting technical conclusions on failure mode of the SSF diesel fuel oil pump seal (aging vs. foreign material intrusion)

(2) NRC 2288543 - Engine Systems, Inc. (Part 21) - Oconee review and evaluation of applicability and effect

71153 - Followup of Events and Notices of Enforcement Discretion Event Report (IP Section 03.02)

The inspectors evaluated the following licensee event reports (LERs):

(1) LER 05000269/2019-001-00, Unit 1 Standby Shutdown Facility Reactor Coolant Makeup Pump Oil Suction Tubing Failure (ML19225C402). The circumstances surrounding this LER are documented in Inspection Report 05000269/2019090 Section 71152B.

OTHER ACTIVITIES

- TEMPORARY INSTRUCTIONS, INFREQUENT AND ABNORMAL

60855.1 - Operation of an Independent Spent Fuel Storage Installation at Operating Plants Operation of an Independent Spent Fuel Storage Installation at Operating Plants

(1) The inspectors evaluated the licensees independent spent fuel storage installation cask loading for Dry Storage Cask (DSC) 159 from July 8, 2019 through July 10, 2019. Specifically, the inspectors observed the following activities;

• Fuel selection and fuel loading
• Heavy load movement of empty/loaded DSC
• Transfer and transport evolutions
• Radiological field surveys

INSPECTION RESULTS

Inadequate Control of Heavy Load in Spent Fuel Pool Cornerstone Significance Cross-Cutting Report Aspect Section Barrier Integrity Green [H.4] - 71111.13 NCV 05000287/2019003-01 Teamwork Open/Closed Inspectors identified a Green finding and associated non-cited violation (NCV) of Technical Specification (TS) 5.4.1, Procedures, when the licensee failed to properly pre-plan and control a heavy load lift in the Unit 3 spent fuel pool.

Description:

On August 20, 2019, the licensee transported a heavy load across the Unit 3 spent fuel pool in support of a permanent plant modification to upgrade the fuel pool transfer tube isolation valve. Engineers developed an engineering change (EC) 412504 to provide a technical basis for the maintenance activity, a basis for a future engineered lift plan, and to assess and manage the increase in risk that may result from the maintenance activity. The EC concluded that the developed mitigation and handling measures were within the guidelines of site rigging/lifting procedures and the site licensing basis associated with NUREG-0612, Control of Heavy Loads at Nuclear Power Plants, Phase I commitments.

Since the modification (EC 412504) planned to utilize the spent fuel bridge auxiliary hoist to handle a heavy load near spent fuel, a new safe load path was developed and documented in an engineered lift plan. While traversing over the fuel assemblies, the load was to be secured to the bridge by four wire rope safety slings and engineered temporary saddle beams. Once the load was no longer over fuel, near the far end of the pool, the safety slings could be removed, and the load would be suspended from a combination of the bridge auxiliary hoist and four submersible lift bags. The lift plan included an additional restriction that the load shall never be suspended closer than 15 feet horizontally from spent fuel. To satisfy this restriction, reactor engineering relocated spent fuel to create a 17-foot radius from the end of the pool. During planning reviews, these actions and restrictions were considered adequate. However, factors that would apply at the location where the load would transition to a suspended load (such as limitations on the positioning of the bridge and the location of the engineered saddle beams) had not been considered.

As a result, during execution of the modification while transitioning the load to the suspended configuration, riggers suspended the 7,100 pound and 121/2 foot tall valve within approximately five horizontal feet of spent fuel. This load was suspended by the 4,000-pound bridge hoist and a set of four 2,000-pound lift bags. During the transition to the bridge hoist, an air supply line to one of the four lift bags became detached due to contact with the removed safety slings. The bag maintained its buoyancy and was repaired by a diver. The load was then drifted to the final installation area and securely installed on the fuel transfer tube.

NRC inspectors identified that although the equipment used was adequate to suspend the load, the failure to adequately pre-plan the location and physical transition to a suspended configuration resulted in a failure to satisfy the engineered lift plan safe load path restriction of maintaining a 15-foot clearance from fuel. Workers also failed to identify the inability to meet the restriction during work execution because there was an impression that the amount of fuel removed from the area was adequate and because the knowledgeable lift engineer was present for the work. These failures negatively impacted the defense-in-depth approach taken to minimize the potential for adverse interaction of heavy loads with spent fuel.

Corrective Actions: The licensee initiated evaluations to identify organizational causal factors and issued a crew learning to the team to explain the difference between shall and should as defined in procedure AD-HU-ALL-0004, Procedure and Work instruction Use and Adherence.

Corrective Action References: NCR 2289055

Performance Assessment:

Performance Deficiency: The failure to properly pre-plan and control a heavy load lift near spent fuel was a performance deficiency. Specifically, engineers failed to establish conditions that ensured all lift plan restrictions could be met during the evolution and the installation team executed the lift without recognizing that safe load path restrictions were violated.

Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Procedure Quality attribute of the Barrier Integrity cornerstone and adversely affected the cornerstone objective to provide reasonable assurance that physical design barriers protect the public from radionuclide releases caused by accidents or events. Specifically, if the heavy load were dropped on the spent fuel racks, damage to fuel assemblies and a release of fission products could have occurred.

Significance: The inspectors assessed the significance of the finding using IMC 0609 Appendix A, The Significance Determination Process (SDP) for Findings At-Power. Using Exhibit 3, Barrier Integrity Screening Questions associated with the spent fuel pool, the finding was determined to be Green because it did not adversely affect the decay heat removal capabilities or water inventory of the spent fuel pool, was not associated with crane operations that caused mechanical damage to fuel cladding or a fuel bundle misplacement, and did not affect the spent fuel pool neutron absorber, or soluble boron concentration.

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. Inspectors concluded that the error occurred because of a lack of coordination and planning among various departments regarding the location of the transition to a suspended configuration and the amount of spent fuel to remove from the vicinity.

Enforcement:

Violation: Oconee Unit 3 Technical Specification 5.4.1, Procedures, states, in part, that written procedures shall be implemented covering the applicable procedures recommended in Appendix A of Regulatory Guide (RG) 1.33, February 1978. Regulatory Guide 1.33, Quality Assurance Program Requirements (Operation), Appendix A, Paragraph 9.a, Procedures for Performing Maintenance, requires that maintenance that can affect the performance of safety-related equipment should be properly pre-planned and performed in accordance with written procedures, documented instructions, or drawings appropriate to the circumstances. Contrary to the above, on August 20, 2019, EC 412504 and the subsequent engineered lift plan were not properly pre-planned resulting in WO 20185881 being performed with procedures, instructions, and drawings that were not appropriate to the circumstances. Specifically, the plans failed to appropriately describe and control the location where the load could transition from a secured load to a suspended load while maintaining the desired clearance from spent fuel. This failure resulted in a 7,100 pound and 121/2 foot tall valve being suspended within approximately five horizontal feet of spent fuel.

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

Failure to Notify the NRC within Eight Hours following the Discovery of a Condition that could have Prevented the Fulfillment of the Unit 1 Core Flood Systems Safety Function Cornerstone Severity Cross-Cutting Report Aspect Section Not Severity Level IV Not 71111.15 Applicable NCV 05000269/2019003-02 Applicable Open/Closed The inspectors identified a Severity Level (SL) IV non-cited violation (NCV) of 10 CFR 50.72(b)(3)(v) when the licensee failed to notify the NRC within eight hours following the discovery of a condition that could have prevented the fulfillment of a safety function.

Specifically, the Unit 1 core flood system, which is a system needed to mitigate the consequences of an accident, was inoperable because the Unit 1A core flood tank vent valve, 1CF-5, failed to close during a normal venting evolution.

Description:

At approximately 0400 on July 24, 2019, the licensee began to vent the 1A core flood tank (CFT), by opening 1CF-5, due to a rise in pressure resulting from increased seasonal temperatures. The 1A CFT pressure lowered to an acceptable value and the licensee tried to close 1CF-5 to halt the venting. However, 1CF-5 failed to close and the depressurization of the 1A CFT continued until pressure dropped below the TS allowed minimum. The licensee entered TS Limiting Condition for Operation (LCO) 3.5.1, Condition B for one CFT inoperable. The licensee dispatched operators to restore nitrogen overpressure to the tank by aligning the nitrogen feed system. At 0526, the licensee restored the pressure in 1A CFT to above the TS allowed minimum utilizing a continuous nitrogen feed-and-bleed process. At 0744, the licensee closed the manual isolation valve downstream of 1CF-5 and isolated the nitrogen feed, stabilizing 1A CFT pressure at an acceptable level.

Later that day, licensee engineers determined that although the nitrogen feed-and-bleed process was established to raise the CFT pressure back above the TS allowed minimum, the 1A CFT remained inoperable until the closure of the downstream manual isolation valve (approximately 2 hours later). This conclusion was based on: 1) a safety analysis that credited 1A CFT injection later during an accident than what the 1A CFT would have been able to accomplish on the morning of July 24, 2019, and 2) calculated depressurization rate without crediting the continuous feed of nitrogen, since nitrogen would be manually isolated by procedure under accident conditions. The total inoperability time of the 1A CFT remained less than any required action time to shut down the Unit, so operation in a condition prohibited by technical specifications did not occur.

Resident inspectors reviewed licensee corrective action documents and noted that no discussion of a potential 10 CFR 50.72 missed notification was documented. The inspectors questioned the licensee on whether a 10 CFR 50.72 notification should have been made due to the vent valve failure causing the loss of the CFT safety function. The licensee confirmed that they had missed notifying the NRC within eight hours.

Corrective Actions: The licensee took corrective actions that included initiating a Licensee Event Report to be submitted to the NRC within 60 days, incorporating this operating experience into continuing and initial senior reactor operator, shift technical advisor, and shift manager training, initiating a Crew Learning, and developing an Operations Supplemental Information Package.

Corrective Action References: NCR 2288160.

Performance Assessment:

The inspectors determined this violation was associated with a minor ROP performance deficiency.

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: Based on the examples provided in Section 6.9 of the Enforcement Policy, dated May 28, 2019 Inaccurate and Incomplete Information of Failure to Make a Required Report, the performance deficiency was determined to be a SL IV violation. Specifically, Example 6.9 states that a SL IV violation involves a failure to make a report to the NRC in accordance with 10 CFR 50.72.

Violation: 10 CFR 50.72, Immediate notification requirements for operating nuclear power reactors, Section (b)(3)(v) requires, in part, the licensee to notify the NRC as soon as practical and in all cases within eight hours of the occurrence of any event or condition that at the time of discovery could have prevented the fulfillment of the safety function of structures or systems that are needed to mitigate the consequences of an accident. Contrary to the above, on July 24, 2019, the licensee failed to notify the NRC within eight hours of the Oconee Unit 1A core flood tank vent valve, 1CF-5, failing to close, which rendered the 1A CFT inoperable and resulted in the loss of the core flood systems safety function, which is needed to mitigate the consequences of an accident.

Enforcement Action: This violation is being treated as an 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 October 21, 2019, the inspectors presented the integrated inspection results to J. Ed Burchfield, Jr. and other members of the licensee staff.

DOCUMENTS REVIEWED

Inspection Type Designation Description or Title Revision Procedure or Date 60855.1 Miscellaneous Oconee Nuclear Station 0 Independent Spent Fuel Storage Installation 10 CFR 2.212 Evaluation for Phase VIII CR 2281189 NUH-003 Updated Final Safety Analysis 14 Report for the Standardized NUHOMS Horizontal Modular Storage System for Irradiated Nuclear Fuel Procedures AD-HU-ALL- Procedure and Work 10 0004 Instruction Use and Adherence AD-HU-ALL- Human Performance Tools 3 0005 MP/0/A/1500/024 Independent Spent Fuel 000 Storage Installation Phase VIII DSC Loading and Storage Work Orders WO 20324189 71111.01 Calculations OSC-10671 PMP Flood Building 1 Assessment and Leak Rate Data OSC-8849 Design Inputs for Aux. Bldg. 1 Flood Protection due to MFDW Line Break or Crack in East Penetration Rooms OSC-9010 HELB Flood Impoundment 3 Design, Units 1, 2, and 3 for East Penetration Room Corrective 1905081, 2126024, 2287997 Action Documents Drawings O-0320-C Standby Shutdown Facility 9 Sections Concrete O-0950-C Electrical Equipment Layout 45 Outdoors Computer Cable Routing O-0954-A Electrical Equipment Layout 1 Standby Shutdown Facility O-PDF-0003 Event Flood Barriers 5 O-PDF-0003 Event Flood Barriers 5A Engineering 401069 Resolution of Nonconformance 3 Changes Related to ONS Site Grade and Removal of Sandbags Inspection Type Designation Description or Title Revision Procedure or Date NSM ON-2347 Power Supply for SSF Flood 0 Barrier Sump Pump Miscellaneous Oconee Nuclear Oconee Nuclear Door Ways 1/9/2016 Station Site Survey Data Site Directive Control of Passive Design 9 3.2.16 Features Procedures AP/0/A/1700/006 Natural Disaster 31 MP/0/A/3005/001 Flood Outlet Devices and 3 Flood Barriers PM RP/0/A/1000/035 Severe Weather Preparations 4 71111.04Q Calculations OSC-10671 Civil Assessment for 1 Probabilistic Maximum Precipitation (PMP) Flood Concerns, Building: 230 kV Relay House Corrective NCR 2282472, 2282507, Action 2284859 Documents PRR 2282557, TRF 2285442 Drawings O-0702-B One Line Diagram 4160 and 26 600V Essential Load Centers Auxiliary Power Systems Standby Shutdown Facility O-0703-K One Line Diagram 600V and 79 208V Essential Motor Control Centers Auxiliary Power Systems Standby Shutdown Facility O-0703-L One Line Diagram 24 208/120VAC & 120VAC Power Panelboards O-PDF-0003 ARCH - Event Flood Barriers - 005 Plan OFD-101A-3.3 Unit 3 High Pressure Injection 31 System OFD-121A-1.4 Flow Diagram of Condensate 35 System (Hotwell Pumps, Condensate Coolers, Generator Water Coolers, & Hydrogen Coolers) OFD-121A-1.7 Flow Diagram of Condensate 45 System (Upper Sure Tanks 1A

                                          & 1B, Upper Surge Tank

Dome, & Condensate Storage Tank) Inspection Type Designation Description or Title Revision Procedure or Date OFD-121A-1.8 Flow Diagram of Condensate 25 System (Condensate Make-up

                                        & Emergency FDW Pump

Suction) OFD-121B-1.3 Flow Diagram of Feedwater 41 System (Final Feedwater) OFD-121D-1.1 Flow Diagram of Emergency 38 Feedwater System OFD-127C-1.2 Flow Diagram of Nitrogen 5 System (Nitrogen Supply to 1FDW-315/1FDW-316) OSFD-121D-1 Summary Flow Diagram of 9 Emergency Feedwater System Miscellaneous EC 408447 Resolution of Nonconformance 003 Related to ONS Site Grade and Removal of Sandbags OSS-0254.00- (MECH) Design Basis 39 00-1005 Specification for the Standby Shutdown Facility Auxiliary Service Water System OSS-0254.00- (ELECT) DBD for the 017 00-2014 4160/600/120V SSF Essential AC Power System Procedures AD-DC-ALL- Writers Manual for Procedures 9 202 and Work Instructions AD-EG-ALL- Configuration Management 5 1106 and Margin Management AD-HU-ALL- Procedure and Work 10 0004 Instruction Use and Adherence AD-OP-ALL- Plant Status Control 3 204 AM/0/A/1300/059 Pump - Submersible - 012 Emergency SSF Water Supply

                                        - Installation and Removal

AP/0/A/1700/025 Standby Shutdown Facility 063 Emergency Operating Procedure OP/0/A/1600/005 SSF Normal Power 43 OP/0/A/1600/007 SSF Diesel Air System 020 OP/0/B/1600/011 SSF Systems Isolation 27 Procedure OP/1/A/1106/006 Emergency Feedwater System 132 Work Orders WO 20273756-02, 20304779 71111.05Q Fire Plans CSD-ONS-PFP- Pre-Fire Plan for U1 Auxiliary 000 1AB-0822 Building Elevation 822 CSD-ONS-PFP- Pre-Fire Plan for U1 Auxiliary 000 Inspection Type Designation Description or Title Revision Procedure or Date 1AB-0838 Building Elevation 838 CSD-ONS-PFP- Pre-Fire Plan for U2 Auxiliary 000 2AB-0838 Building Elevation 838 CSD-ONS-PFP- Pre-Fire Plan for U3 Auxiliary 000 3AB-0822 Building Elevation 822 Miscellaneous O-0310-K-016 Auxiliary & Reactor Building - 012 Unit 1 Fire Protection Plan & Fire Barrier, Flood & Pressure Boundaries Plan at EL 838+0

                                        & 844+6

Procedures AD-EG-ALL- Duties of a Fire Watch 8 22 MP/0/A/1705/032 Fire Extinguishers - Auxiliary 002 A Building - Monthly Inspection 71111.11Q Procedures AD-EP-ALL-0803 Evaluation and Critique of Drills 4 and Exercises AD-LS-ALL-0006 Notification/Reportability 2 Evaluation AD-OP-ALL- Conduct of Operations 15 1000 AD-OP-ALL- Conduct of Abnormal 3 1001 Operations AD-TQ-ALL-0420 Conduct of Simulator Training 15 and Evaluation AP/1/A/1700/011 Recovery from Loss of Power 059 AP/1/A/1700/016 Abnormal Reactor Coolant 036 Pump Operation AP/1/A/1700/020 Loss of Component Cooling 012 EP/1/A/1800/001 Unit 1 EOP Immediate Manual 002 Actions and Subsequent Actions OMP 1-18 Oconee - Specific 045 Implementation Standard During Abnormal and Emergency Events OMP 1-24 Operations Communication 017 Standard OP-OC-ASE-44 Simulator Exercise Guide 02 PT/3/A/0290/004 Turbine Stop Valve Testing 014 RP/0/A/1000/001 Emergency Classification 006 RP/0/A/1000/002 Control Room Emergency 013 Coordinator Procedure 71111.12 Corrective NCR 2272633 Action Inspection Type Designation Description or Title Revision Procedure or Date Documents Procedures AD-EP-ALL-0803 Evaluation and Critique of Drills 4 and Exercises AD-LS-ALL-0006 Notification/Reportability 2 Evaluation AD-OP-ALL- Conduct of Operations 15 1000 AD-OP-ALL- Conduct of Abnormal 3 1001 Operations AD-TQ-ALL-0420 Conduct of Simulator Training 15 and Evaluation AP/1/A/1700/011 Recovery from Loss of Power 059 AP/1/A/1700/016 Abnormal Reactor Coolant 036 Pump Operation AP/1/A/1700/020 Loss of Component Cooling 012 EP/1/A/1700/001 Unit 1 EOP Immediate Manual 002 Actions and Subsequent Actions OMP 1-18 Oconee - Specific 045 Implementation Standard During Abnormal and Emergency Events OMP 1-24 Operations Communication 017 Standard OP-OC-ASE-44 Simulator Exercise Guide 02 RP/0/A/1000/001 Emergency Classification 006 RP/0/A/1000/002 Control Room Emergency 013 Coordinator Procedure 71111.13 Calculations OSC-1160 Postulated Cask Drop 6 Accident-Poison Racks Drawings 21777-28 Refueling Machine General D3 Arrangement O-308C-SLP Auxiliary Building Plan at Elev. 1 838 + 0 & 844 + 0 Safe Load Paths Miscellaneous Projected ERAT Risk Profile Oconee Nuclear Station Plant Status Package on July 16 and 17, 2019 NUMARC 93-01 Industry Guideline for 4a Monitoring the Effectiveness of Maintenance at Nuclear Power Plants Regulatory Guide Monitoring the Effectiveness of 4 1.160 Maintenance at Nuclear Power Plants Inspection Type Designation Description or Title Revision Procedure or Date Procedures AD-EG-ALL- Conduct of Probabilistic Risk 3 1004 Analysis Engineering AD-EG-ALL- Preparation and Control of 14 1132 Design Change Engineering Changes AD-NF-ALL-0501 Electronic Risk Assessment 4 Tool (ERAT) AD-NF-NGO- Probabilistic Assessment 3 0502 (PRA) Model Technical Adequacy AD-WC-ALL- On-Line Work Management 14 200 AD-WC-ALL- On-Line Risk Management 1 240 Process OP/0/A/1107/011 Sharing Startup Transformers 014 F Between Units PD-MN-ALL- Nuclear Rigging & Lifting 7 0009 Program Work Orders WO 20173938, 20330072 71111.15 Calculations KC-2190 Failure Mode and Effects 4 Analysis (FMEA) for the Keowee 13.8kV Switchgear

                                       (KPF) Power Feeds to

Protected Service Water System (PSW) Switchgear

                                       (B6T/B7T)

OSC-473 LPSW Between Discharge 39 Nozzles of Decay Heat Cooler 2B, RB Component Coolers 1A, A, 2A, Aux. Bldg. and T.B. Basement Floor Piping Analysis Problem No. 2-14-05 OSC-5649 LPSW Test Acceptance 19 Criteria OSC-8159 SSF Diesel Fuel Oil Storage 2 Tank Inspection Corrective NCR 1937031, 2283825, Action 2283504, 2285028, 2288160 Documents PRR 2283847, 2285047, 285048, 2285049 273613, 2285443 Drawings KEE-0117-01-0A Elementary Diagram Keowee 1 Oconee Remote Controls Inspection Type Designation Description or Title Revision Procedure or Date KEE-0119 Elementary Diagram PSW 2 Emergency Power 13.8kV Feeder Bkr KPF-9 Control Circuit KM 303- Instruction Manual for 15kV 9 0036.001 Switchgear O-0706 One Line Diagram Essential 15 SSF 125 VDC Auxiliary Power Systems OFD-124B-1.1 Flow Diagram of Low Pressure 67 Service Water System

                                        (Auxiliary Building Services)

Engineering 115245 Replace Charging Spring 0 Changes Relays in Bkrs KPF-09 & 10 91875 Keowee AC Power Supply Tie- 78 ins Miscellaneous LCOTR Number SSF Standby Battery Cell #5 O-0-19-00905 does not meet Category A or B Tracking Only NSD-104 Material 40 Condition/Housekeeping, and Seismic Concerns OSS-0254.00- (ELECT) SSF 125 VDC 14 00-2020 Essential Power System Procedures MP/0/A/5050/039 Diesels - SSF - 12 and 16 013 Cylinder - Preventive Maintenance and Inservice Inspection - 10 and 12 Year OP/0/A/1600/006 Operation of SSF KSF1/KSF2 026 Inverters and SSF CSF/CSFS Battery Chargers OP/1/A/1104/001 Core Flooding System 81 PT/3/A/0251/001 Low Pressure Service Water 96 Pump Test performed on August, 9, 2019 Work Orders WO 20328847, 02063567 WR 20147967 71111.18 Calculations KC-2079 Governor Oil Pressure Tank, 7 Oil and Air Minimum Design Pressure OSC-9314 NFPA 805 Transition Risk- 6 Informed Performance-Based Fire Risk Evaluation Corrective 01905036, 02294192 Inspection Type Designation Description or Title Revision Procedure or Date Action Documents Miscellaneous Technical Specification Bases 4 3.7.10 Duke Letter RA- Duke Energy Response to 19-0116 dated NRC Request for Additional February 26, Information (RAI) Related to 2019 Oconee License Amendment Request 2017-05 Procedures AP/0/A/2000/002 Keowee Hydro Station - 22 Emergency Start EP/2/A/1800/001 Unit 2 EOP Enclosures 5.41 - 7 0Q 5.46 71111.19 Drawings OEE-260-15 Elementary Diagram Waste 10 Disposal System RB Normal Sump Discharge VLV. 2LWD- 001 2LWDVA0001 OEE-165-04 Elementary Diagram Protected 5 Service Water Steam Generator 1B Flow Control MOV 1 PSW-24 OFD-101A-3.3 Flow Diagram of High Pressure 31 Injection System (Charging Section) OFD-101A-3.4 Flow Diagram of High Pressure 46 Injection System (Charging System) Engineering 415742 Changes Procedures IP/0/A/0101/001 Low Risk maintenance 18 Configuration Control IP/3/A/0202/001 High Pressure Injection System 006 D Emergency HP Injection Flow Instrument Calibration PT/0/A/0400/005 SSF Auxiliary Service Water 069 Pump Test PT/1/A/0261/010 Essential Siphon Vacuum 020 System Test PT/2/A/0152/014 Liquid Waste Disposal System 8 Valve Stroke Test Work Orders WO 20173119-05, 20173938, 240445, 20274863 71111.22 Calculations OSC-2280 LPSW NPSHA and Minimum 20 Required Lake Level OSC-4489 Predicted Unit 3 LPSW System 11 Response to a Large-Break Inspection Type Designation Description or Title Revision Procedure or Date LOCA with Single Failure Using a Benchmarked Hydraulic Computer Model OSC-5649 LPSW Test Acceptance 19 Criteria (TAC) OSC-6098 LPSW Instrument Uncertainty 1 Corrective NCR 2271297 Action Documents Drawings OEE-120 Elementary Diagram Channel 18 A Keowee Emergency Start OEE-120-01 Elementary Diagram Channel 18 B Keowee Emergency Start OEE-120-1-A Elementary Diagram Channel 10 B Keowee Emergency Start Contact Development OEE-120-A Elementary Diagram Channel 10 A Keowee Emergency Start Contact Development OEE-320 Elementary Diagram Channel 6 A Keowee Emergency Start

                                        (Unit 3)

OEE-320-1 Elementary Diagram Channel 6 B Keowee Emergency Start

                                        (Unit 3)

Miscellaneous ESI - EMD Owners Group 9 Recommended Maintenance Program - Mechanical Nuclear Standby Emergency Diesel Generators ONTC-3-124A- Test Acceptance Criteria 2 0001-001 Procedures PT/0/A/0620/016 Keowee Hydro Emergency 53 Start Test PT/3/A/0203/006 Low Pressure Injection Pump 094 A Test - Recirculation Work Orders WO 20249209-01, 20321990, 20325326-01, 20325326-05 71114.06 Miscellaneous ONS Drill 19-02 Scenario Manual Critique Report for July 17, 2019 Drill 71151 Miscellaneous Safety System Functional Failures (SSFF) PI Summary Report for period ending in June 2019, Units 1, 2, 3 Mitigating Systems 26 Inspection Type Designation Description or Title Revision Procedure or Date Performance Index (MPSI) Basis Document MSPI Derivation Report for period ending June 2019, Units 1, 2, 3 Heat Removal System MSPI Indicator Margin Report for period ending June 2019, Units 1, 2, 3 Heat Removal System CP/0/A/2005/022 Determination of Reported 006 Tech Spec Dose Equivalent Iodine-131 71152 Corrective 2186873, 1824462, 02288543, Action 02289565 Documents Miscellaneous Preventive Maintenance Change 02277613 2| ]]