IR 05000348/2019003

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Integrated Inspection Report 05000348/2019003 and 05000364/2019003
ML19311C482
Person / Time
Site: Farley  Southern Nuclear icon.png
Issue date: 11/07/2019
From: Alan Blamey
NRC/RGN-II
To: Gayheart C
Southern Nuclear Operating Co
Geanette D
References
EPID I-2019-003-0026 IR 2019003
Download: ML19311C482 (14)


Text

ber 7, 2019

SUBJECT:

JOSEPH M. FARLEY NUCLEAR PLANT - INTEGRATED INSPECTION REPORT 05000348/2019003 AND 05000364/2019003

Dear Ms. Gayheart:

On September 30, 2019, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Joseph M. Farley Nuclear Plant. On October 22, 2019, the NRC inspectors discussed the results of this inspection with Mr. Charles Kharrl 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. We are treating this violation as a non-cited violation (NCV) consistent with Section 2.3.2 of the Enforcement Policy.

If you contest the violation or significance or severity of the violation documented in this inspection report, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the U.S. Nuclear Regulatory Commission, ATTN:

Document Control Desk, Washington, DC 20555-0001; with copies to the Regional Administrator, Region II; the Director, Office of Enforcement; and the NRC Resident Inspector at Farley.

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/

Alan J. Blamey, Chief Reactor Projects Branch 2 Division of Reactor Projects Docket Nos. 05000348 and 05000364 License Nos. NPF-2 and NPF-8

Enclosure:

As stated

Inspection Report

Docket Numbers: 05000348 and 05000364 License Numbers: NPF-2 and NPF-8 Report Numbers: 05000348/2019003 and 05000364/2019003 Enterprise Identifier: I-2019-003-0026 Licensee: Southern Nuclear Operating Co., Inc Facility: Joseph M. Farley Nuclear Plant Location: Columbia, AL Inspection Dates: July 01, 2019 to September 30, 2019 Inspectors: P. Meier, Senior Resident Inspector K. Miller, Resident Inspector M. Kirk, Resident Inspector Approved By: Alan J. Blamey, Chief Reactor Projects Branch 2 Division of Reactor Projects Enclosure

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at Joseph M. Farley Nuclear Plant 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 Unit 1 turbine driven auxiliary feed water pump steam supply valve failure Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green None (NPP) 71111.15 Systems NCV 05000348/2019003-01 Open/Closed A self-revealed green finding and associated non-cited violation (NCV) of Technical Specification 5.4.1, Procedures was identified when the licensee failed to follow procedural guidance in 2012 for work that affected the performance of the Unit 1 turbine driven auxiliary feedwater system. Instrument air tubing was installed incorrectly on the Unit 1 C steam generator steam supply to the turbine driven auxiliary feedwater pump valve actuator causing premature failure that rendered one of two required steam supply valves inoperable.

Additional Tracking Items None.

PLANT STATUS

Unit 1 began the report period at approximately 100 percent rated thermal power (RTP) and operated at or near 100 percent RTP until September 29. On September 29, Unit 1 was taken offline for a planned refueling outage and stayed offline through the end of the report period.

Unit 2 began the report period at or near 100 percent RTP until July 24, when reactor power was reduced to approximately 85 percent due to the partial loss of cooling tower fans. Unit 2 achieved approximately 100 percent RTP on July 25 following restoration of cooling tower fans. The Unit 2 reactor was manually tripped on September 21, due to indicated high vibration on the 2C Reactor Coolant Pump. The reactor was restarted on September 22 and eventually achieved 100 percent RTP on September 25 and operated at or near 100 percent RTP level through the end of the report 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.

REACTOR SAFETY

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 (FSAR Chapter 2; FNP-0-AOP-21.0):
  • Unit 1 and 2 auxiliary buildings
  • Unit 1 and 2 containment equipment doors
  • Diesel Building

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) Unit 1 'A' motor driven auxiliary feedwater system during the Unit 1 'B' motor driven auxiliary feedwater pump surveillance on August 14, 2019 (WO SNC9954030).
(2) Unit 2 'B' train containment spray system with the 'A' train of containment spray inoperable for planned maintenance on August 27, 2019 (FNP-2-SOP-9.0A; PI&D D205038).
(3) Unit 1 turbine driven auxiliary feedwater system with the Unit 1 motor driven auxiliary feedwater pump out of service for maintenance on September 16, 2019 (WO SNC658041).

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

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

(1) Unit 1 auxiliary building 100 ft. elevation hallway (fire zone 171) on August 15, 2019 (FNP-1-FPP-1).
(2) Unit 1 'C' charging pump room (fire zone 173) on August 15, 2019 (FNP-1-FPP-1).
(3) Unit 1 'B' charging pump room (fire zone 174) on August 15, 2019 (FNP-1-FPP-1).
(4) Unit 1 'A' charging pump room (fire zone 181) on August 15, 2019 (FNP-1-FPP-1).

71111.06 - Flood Protection Measures Inspection Activities - Internal Flooding (IP Section 02.02a.)

The inspectors evaluated internal flooding mitigation protection in the:

(1) Unit 2 component cooling water heat exchanger room on July 2, 2019 (CR10611070; Calculation BM-99-1932-001).

==71111.11Q - Licensed Operator Requalification Program and Licensed Operator Performance Licensed Operator Performance in the Actual Plant/Main Control Room (IP Section 03.01) (1 Sample)

(1) The inspectors observed and evaluated licensed operator performance in the Control Room during a response following a Unit 2 reactor trip due to 2C reactor coolant pump high vibration concerns on September 21, 2019 and Unit 2 re-start activities on September 23, 2019 (CR 10648227).

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

(1) The inspectors observed and evaluated the control room simulator crew response to an emergency response drill on August 13, 2019.
(2) The inspectors observed and evaluated just-in-time training of the operators in the control room simulator on September 22, 2019, in preparation for the Unit 2 re-start following a September 21, 2019, reactor trip.

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) Fire pump house material condition on July 9-10, 2019 (CR10622995).
(2) Service water intake system material condition (FNP-0-M-82).

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) Unit 2 turbine driven auxiliary feedwater system planned maintenance on July 17, 2019 (WO SNC979772).
(2) Unit 1 'C' component cooling water pump heat exchanger and Unit 1 'C' service water pump maintenance on July 29 - August 1, 2019 (NMP-AD-050).
(3) Troubleshooting and repair associated with the Unit 1 rod control urgent failure alarm that occurred on August 5, 2019 (CR10635629).
(4) Risk associated with the Unit 2 turbine building service water isolation and Unit 2

'A' containment spray pump out of service for planned maintenance on August 27, 2019 (WO SNC963267).

(5) Unit 1 'B' motor driven auxiliary feedwater pump planned maintenance; high risk work in the high voltage switchyard; heavy lift of the new Unit 1 hydrogen cooler over the Unit 1 main turbine crossover piping on September 16, 2019 (WO SNC658041).

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) Two locations of through wall leaks on Unit 2 service water piping located near the 2A and 2C service water pumps identified on July 31, 2019 (CR 10633466, CR

===10633640).

(2) Unit 1 turbine driven auxiliary feedwater pump steam supply valve not opening on demand on July 11, 2019 (CR10627909).
(3) Unit 1 turbine driven auxiliary feedwater water pump magnetic speed sensor 'A' damage identified on July 22, 2019 (CR10630906).
(4) Unit 2 'E' 600 volt load center cooler not running with a high room temperature identified on July 29, 2019 (CR10633003).
(5) Plant computer thermal power calculation accuracy concern for Unit 2 identified on August 12, 2019 (CR10636696).
(6) Unit 2 'B' train service water lubrication and cooling strainer would not backwash on September 17, 2019 (CR10646730).

71111.18 - Plant Modifications Severe Accident Management Guidelines (SAMG) Update (IP Section 03.03)

(1) Verified the site Severe Accident Management Guidelines are updated with the PWR owner's group revised generic severe accident technical guidelines in accordance with the processes in NEI 14-01, revision 1 (FNP-1-SAG-1; ML15357A213).

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

The inspectors evaluated the following post maintenance tests:

(1) Unit 1 'B' steam generator pressure transmitter (PT-484) replacement on July 3, 2019 (WO SNC636729).
(2) Unit 2 turbine driven auxiliary feedwater pump maintenance and trip-and-throttle valve lubrication on July 17, 2019 (WO SNC979772).
(3) Unit 1 'C' component cooling water pump breaker replacement on July 30 through August 1, 2019 (WO SNC677643).
(4) Unit 2 'B' atmospheric relief valve actuator air line replacement on August 8, 2019 (WO SNC1034961).
(5) Unit 1 'B' motor driven auxiliary feedwater pump breaker replacement on August 16, 2019 (WO SNC658041).

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

(1) Unit 1 primary coolant system (RCS) gross activity determination on September 10, 2019 (FNP-1-STP-741.0).
(2) Unit 2 1-2A emergency diesel generator load rejection surveillance on September 19, 2019 (FNP-2-STP-80.20).

Inservice Testing (IP Section 03.01) ===

(1) Unit 2 'A' motor driven auxiliary feedwater pump quarterly surveillance on July 2, 2019 (FNP-2-STP-22.1).

FLEX Testing (IP Section 03.02) (1 Sample)

(1) Observed surveillances of FLEX diesel generators and diesel pumps on August 21, 2019 (WO SNC944230).

==71114.06 - Drill Evaluation Select Emergency Preparedness Drills and/or Training for Observation (IP Section 03.01) (2 Samples)

(1) The inspectors observed and evaluated a full participation training drill from the control room (simulator) and technical support center with the technical support center, emergency operations facility, operational support center and control room (simulator) fully staffed on June 26, 2019. Event classification, notification, and dose assessment opportunities were provided to contribute to drill and exercise performance indicators. The scenario primarily involved a steam generator tube rupture that resulted in offsite dose.
(2) The inspectors observed and evaluated a full participation training drill from the technical support center with the technical support center, emergency operations facility, operational support center and control room (simulator) fully staffed on August 13, 2019. Event classification, notification, and dose assessment opportunities were provided to contribute to drill and exercise performance indicators. The scenario primarily involved a rod ejection resulting in a small break LOCA and a degraded containment barrier.

OTHER ACTIVITIES - BASELINE

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

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

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

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

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

BI02: RCS Leak Rate Sample (IP Section 02.11) (2 Samples)

(1) Unit 1 (July 1, 2018 - June 30, 2019).
(2) Unit 2 (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) Poor maintenance practices involving work planning and procedure usage resulting in degraded safety-related equipment (CAR 276360 & 275073).

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

(1) The inspectors evaluated the licensee's response to a Unit 2 down-power to 85% due to a cooling water tower power supply loss on July 24, 2019 (CR10631722).
(2) The inspectors evaluated a Unit 2 manual reactor trip and the licensee's response due to concerns with high vibrations on the 2C reactor coolant pump on September 21, 2019 (CR10648227; EN54287).

INSPECTION RESULTS

Unit 1 turbine driven auxiliary feed water pump steam supply valve failure Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green None (NPP) 71111.15 Systems NCV 05000348/2019003-01 Open/Closed A self-revealed green finding and associated non-cited violation (NCV) of Technical Specification 5.4.1, Procedures was identified when the licensee failed to follow procedural guidance in 2012 for work that affected the performance of the Unit 1 turbine driven auxiliary feedwater system. Instrument air tubing was installed incorrectly on the Unit 1 C steam generator steam supply to the turbine driven auxiliary feedwater pump valve actuator causing premature failure that rendered one of two required steam supply valves inoperable.

Description:

On July 11, 2019, with Unit 1 in mode 1 at 100% reactor power, while performing a surveillance on the turbine driven auxiliary feedwater pump steam supply from the 1C steam generator (valve 3235B), the licensee discovered that the valve did not indicate open in the control room when taken to start via the control room hand switch in accordance with the surveillance procedure (FNP-1-STP-21.3). Work order SNC1033896 identified a leak on the instrument air flex hose on the actuator to be the cause of the failure. Subsequently, the licensee declared the 1C steam supply valve inoperable.

The failed Swagelok FM series flex hose replaced the original copper tubing. The residents determined that work order SNC378304 (April 2012) performed repairs to the valve that required dismantling of the actuator. While the April 2012 work order did not contain detailed work instructions, the subsequent work order SNC401204 (October 2013) to rebuild the operator contained an as found picture of the actuator with the FM series flex hose installed.

Standard engineering specifications and existing procedural guidelines dictate the tubing material and installation requirements. Farley engineering specification SS-1109-02 specifies the requirements for piping, including instrument tubing for safety-related applications. The specification requires copper tubing for control air and supply, as in the case of the steam supply valve actuator. This was in effect since August 1982. FNP-0-PMP-303, version 8, is a safety-related plant modification procedure that provides guidelines for on-site routing and supporting of all codes and classes of tubing. FNP-0-PMP-303, dated June 13, 2002, allows for the use of flex tubing connecting to control valves, such as the failed flex hose discussed above, in lieu of the specified copper tubing.

However, the procedure specifically states for seismic category I valves (i.e. 3235B) only the instrument air supply tubing may be replaced with blanket approval. The supply tubing is that tubing between the instrument air header and the first component on the air operated valve. The tubing in question is located on the actuator itself and does not connect to the air header. Therefore, an engineering design package would be required to change from copper tubing to flex tubing. A design package could not be located. In addition, FNP-0-PMP-303 also requires that if flexible tubing be used, it should be installed in accordance with vendor recommendations. Based on the resident inspector reviews and Swagelok Hose and Tubing instructions (MS-01-180, revision S, June 2019), the flex tubing was not installed correctly. Upon examining a February 2013 picture of valve 3235B and field measurements, the inspectors determined that the flex tubing exceeded the vendor minimum bend radius, which reduces hose life in accordance with the Swagelok guide. In addition, the steam supply valve is subject to constant vibration while Unit 1 is at power. The vendor guidance recommends evaluating system vibration because metal flex hoses may not be appropriate for systems with constant vibration. An evaluation to assess the constant vibration could not be located. Therefore, the resident inspector determined that the licensee did not follow FNP-0-PMP-303 correctly by mis-applying the option to replace the copper tubing with flex tubing and not following the vendor recommendations for the installation of the flex tubing. This resulted in the unexpected failure of the air line and the steam supply valve.

Corrective Actions: The leaking flex hose was replaced with copper tubing, as originally designed, via work order SNC 1033896. Following successful post maintenance testing and stroke time testing, valve 3235B was declared operable on July 15, 2019.

Corrective Action References: CR10627909; WO SNC1033896

Performance Assessment:

Performance Deficiency: The licensee failed to implement a procedure in accordance with Tech Spec 5.4.1a. and Regulatory Guide 1.33, Revision 2, Appendix A. Specifically, the licensee did not follow FNP-0-PMP-303, Guidelines for Site-Routing and Supporting of Tubing, in 2012 for work that affected the performance of safety-related equipment and resulted in the inoperability of the Unit 1 turbine driven auxiliary feed water pump steam supple valve, 3235B.

Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Equipment Performance attribute of the Mitigating Systems cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. The mitigating system cornerstone was affected because the safety function of the Unit 1 turbine driven auxiliary feedwater system is to supply water to the steam generator for core cooling during certain design bases accidents. If left uncorrected, the risk of core damage slightly increases.

Significance: The inspectors assessed the significance of the finding using Appendix A, The Significance Determination Process (SDP) for Findings At-Power. The finding was not a deficiency affecting the design or qualification of a structure, system, or component; and did not represent a loss of system and/or function. It was determined that the finding may have represented an actual loss of at least a single train for greater than its Technical Specification allowed outage time and a detailed risk analysis was required in accordance with IMC 0609 Appendix A. A regional SRA conducted a quantitative risk evaluation using SAPHIRE Version 8.2.9 and Farley SPAR model Version 8.57. In completing the evaluation, the SRA assumed that the common cause failure probability for both turbine driven auxiliary feedwater pump steam supply valves was not part of the degraded condition caused by the improper use of procedure FNP-0-PMP-303. While improper use of a procedure would normally be a candidate for common cause contribution, in this case the tubing on HV3235A (from SG 1B)was not modified, nor planned to be, and therefore valve HV3235A was not affected by the procedure. The Senior Reactor Analyst (SRA) also assumed an exposure time using the t/2 rules from RASP Handbook Volume 1, Section 2.4, as the tubing failure could have occurred at any time after the previously successful run on March 27, 2019. The result was a change in core damage frequency of less than 1E-6/year, which was of very low safety significance (Green). The dominant sequence was a total loss of service water with operator failure to recover, failure of auxiliary feedwater, and failure of main feedwater. Remaining mitigation capability included recovery of the failed valve and motor driven auxiliary feedwater pumps.

Cross-Cutting Aspect: Not Present Performance. No cross cutting aspect was assigned to this finding because the inspectors determined the finding did not reflect present licensee performance.

Enforcement:

Violation: Technical Specifications 5.4.1.a requires, in part, written procedures shall be implemented covering the applicable procedures recommended in Regulatory Guide 1.33, Revision 2, Appendix A, February 1978. Section 9.a of Appendix A of Regulatory Guide 1.33 requires in part, maintenance that can affect the performance of safety-related equipment should be properly performed in accordance with written procedures, documented instructions, or drawings appropriate to the circumstances.

Contrary to the above, the turbine driven auxiliary feedwater pump steam supply valve from the 1C steam generator actuator airline replacement performed in 2012 was done without specific work procedures or instructions. FNP-0-PMP-303 provides specific guidelines for the replacement of instrument air line copper tubing. Despite this, the existing copper tubing was inappropriately replaced and installed incorrectly resulting in an inoperable steam supply to the turbine driven auxiliary feedwater pump.

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 22, 2019, the inspectors presented the integrated inspection results to Mr.

Charles Kharrl and other members of the licensee staff.

DOCUMENTS REVIEWED

Inspection Type Designation Description or Title Revision or

Procedure Date

71111.15 Drawings D-2000132 P&ID - River Water, Service Water and Circulating Water 24

System

Procedures NMP-AD-012 Operability Determinations and Functionality Assessments 13.3

11