05000390/LER-2017-011

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LER-2017-001, Failure to Enter Technical Specification 3.6.3 for Containment Isolation Valve
Watts Bar Nuclear Plant, Unit 1
Event date: 08-23-2017
Report date: 10-23-2017
Reporting criterion: 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
3902017001R00 - NRC Website
LER 17-011-00 for Watts Bar, Unit 1, Regarding Failure to Enter Technical Specification 3.6.3 for Containment lsolation Valve
ML17296A329
Person / Time
Site: Watts Bar Tennessee Valley Authority icon.png
Issue date: 10/23/2017
From: Simmons P
Tennessee Valley Authority
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML17296A329 (7)


comments regarding burden estimate to the Information Services Branch (T-2 F43). U.S. Nuclear Regulatory Commission, Washington. DC 20555-0001. or by e-mail to Infocollects.Resource@nrc.gov. and to the Desk Officer. Office of Information and Regulatory Affairs, NEOB-10202. (3150-0104). Office of Management and Budget. Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to. the information collection.

I. PLANT OPERATING CONDITIONS BEFORE THE EVENT

Watts Bar Nuclear Plant (WBN) Unit 1 was at 100 percent rated thermal power (RTP) .

II. DESCRIPTION OF EVENT

A. Event Summary On August 23, 2017, Watts Bar Nuclear Plant (WBN) personnel identified Technical Specification (TS) 3.6.3, Containment Isolation Valves, was not entered for on-going work related to 1-FCV-31-330, Incore Instrument Room Air Handler Unit 1B Chilled Water System {EIIS:KM} Isolation Valve {EllS:ISV} . A clearance was placed on the valve May 17, 2017 to support periodic replacement of the valve actuator 0-rings and pressure regulator. Scheduled work was completed on May 19, 2017, however, post maintenance testing was deferred due to additional scheduled work on the Chilled Water System. During a periodic review of upcoming surveillance requirements on August 23, 2017, Operations Work Control discovered the work clearance (1-31-1021-WW) remained in place awaiting post maintenance testing and there was no TS 3.6.3 entry for 1-FCV-31-330 being inoperable. Personnel immediately validated by administrative means the in-place clearance was suitable for compliance with TS 3.6.3 condition A.1 (isolate the affected penetration within

4 hours
4.62963e-5 days
0.00111 hours
6.613757e-6 weeks
1.522e-6 months

) and the tags to comply with TS 3.6.3 condition A.2 (verify the affected penetration flow path is isolated every 31 days) had never been removed or temporarily lifted since initial installation on May 17, 2017.

This event is being reported to the Nuclear Regulatory Commission (NRC) under 10 CFR 50.73(a)(2)(i)(B) as a condition prohibited by Technical Specifications (TS).

B. Inoperable Structures, Components, or Systems that Contributed to the Event No inoperable systems beyond the identified valve contributed to this report.

C. Dates and Approximate Times of Occurrences Date Time Event (EDT) 05/17/17 1642 Clearance 1-31-1021-WW issued for work on 1-FCV-31-330 05/19/17 1020 Maintenance personnel signed-off clearance 1-31-1021-VVVV. Post maintenance testing deferred due other Chilled Water system work.

08/23/17 1011 Operations Work Control personnel discover the failure to track the inoperable valve, 1-FCV-31-330 08/23/17 1029 Entered TS 3.6.3 condition A for penetration X-67 due to work on 1-FCV-31-330 08/23/17 1137 Condition Report 1331287 generated to document deficiency D. Manufacturer and Model Number of Components that Failed During the Event There were no failed components that contributed to this event.

comments regarding burden estimate to the Information Services Branch (T-2 F43), U.S. Nuclear Regulatory Commission. Washington. DC 20555-0001. or by e-mail to Infocollects.Resource@nrc.gov. and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202. (3150-0104). Office of Management and Budget. Washington, DC 20501 If a means used to impose an information collection does not display a currently valid OMB control number. the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

3. LER NUMBER

2017 - 00

E. Other Systems or Secondary Functions Affected

No other systems or secondary functions were affected F. Method of discovery of each Component or System Failure or Procedural Error The failure to properly enter the TS was discovered during a periodic review of upcoming surveillance requirements. The Operations Crew recognized the surveillance could not be performed due to a clearance being in place. Upon further investigation, it was discovered the inoperable valve (1-FCV-31-330) had not been entered into the TS tracking program.

G. Failure Mode and Effect of Each Failed Component Not applicable

H. Operator Actions

Upon discovery of the failure to enter TS 3.6.3 for 1-FCV-31-330, the Operations Work Control Staff immediately entered the TS and ensured compliance with the required actions.

I. Automatically and Manually Initiated Safety System Responses There were no safety system responses associated with this issue.

Ill. CAUSE OF THE EVENT A. The cause of each component or system failure or personnel error, if known.

Failure to enter the inoperable valve into the TS tracking program was a human performance error limited to a single individual.

B. The cause(s) and circumstances for each human performance related root cause.

Failure to enter the inoperable valve into the TS tracking program was a human performance error limited to a single individual

IV. ANALYSIS OF THE EVENT

TS 3.6.3, the containment isolation valve limiting condition for operation (LCO), was derived from the assumptions related to minimizing the loss of reactor coolant inventory and establishing the containment boundary during major accidents. As part of the containment boundary, containment isolation valve operability supports leak tightness of the containment. TS 3.6.3 is applicable in modes 1 through 4. Valve 1-FCV-31-330 is an outside containment isolation valve for the chilled water system. A work clearance was placed to allow periodic replacement of components on the air actuator for 1-FCV-31-330. The clearance boundary also disabled the associated inside containment isolation valve 1-FCV-31-329 thereby meeting the requirements of TS 3.6.3 condition A.1 for penetration X-67. With 1-FCV-31-329 closed and Infocollects.Resource@nrc.gov. and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104). Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to. the information collection.

3. LER NUMBER

2017 00 disabled, the penetration was isolated thereby fulfilling its safety function. Failure to enter TS 3.6.3 condition A.2. to verify the affected flow path isolated every 31 days was determined to be a compliance issue only since the containment penetration was properly isolated per the TS required action at all times.

V. ASSESSMENT OF SAFETY CONSEQUENCES

After investigation, it was determined the safety function of the penetration was constantly maintained by the in-place clearance until time of discovery. At that time, the valve was entered into the TS tracking program to ensure compliance with TS 3.6.3 condition A.2 which verifies the affected penetration flow path is isolated every 31 days. Therefore, while this event is a condition prohibited by TS, the safety implications are minimal.

A. Availability of systems or components that could have performed the same function as the components and systems that failed during the event The in-place work clearance also disabled the inside containment isolation valve 1-FCV-31-329 which served to isolate the containment penetration.

B. For events that occurred when the reactor was shut down, availability of systems or components needed to shutdown the reactor and maintain safe shutdown conditions, remove residual heat, control the release of radioactive material, or mitigate the consequences of an accident Not applicable.

C. For failure that rendered a train of a safety system inoperable, an estimate of the elapsed time from the discovery of the failure until the train was returned to service Not applicable.

VI. CORRECTIVE ACTIONS

This event was entered into the Tennessee Valley Authority (TVA) Corrective Action Program and is being tracked under Condition Report (CR) 1331287.

A. Immediate Corrective Actions

Restored compliance with TS 3.6.3 and conducted investigation.

B. Corrective Actions to Prevent Recurrence or to Reduce Probability of Similar Events Occurring in the Future Coaching was applied for those personnel directly involved with the event. Lessons learned were communicated to the Operations department.

comments regarding burden estimate to the Information Services Branch (T-2 F43), U.S. Nuclear Regulatory Commission, Washington DC 20555-0001. or by e-mail to Infocollects.Resource@nrc.gov. and to the Desk Officer. Office of Information and Regulatory Affairs, NEOB-10202. (3150-0104). Office of Management and Budget. Washington. DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to the information collection.

VII. PREVIOUS SIMILAR EVENTS AT THE SAME SITE

containment penetration within

4 hours
4.62963e-5 days
0.00111 hours
6.613757e-6 weeks
1.522e-6 months

was not met. The event described in this LER is similar since correct actions to comply with the TS were understood, and a human performance error resulted in the correct actions not being performed.

penetration however, an incorrectly placed TS compliance clearance failed to properly isolate the subject penetration. The event described in this LER is different in that TS actions were entered, however a human performance error resulted in the incorrect containment isolation valve being disabled.

VIII. ADDITIONAL INFORMATION

None.

IX. COMMITMENTS

None.