05000390/LER-2016-002

LER-2016-002, Technical Specification Action Not Met for Inoperable Containment Isolation Valve

Watts Bar Nuclear Plant, Unit 1
Event date:	03-05-2016
Report date:	05-04-2016
Reporting criterion:	10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
3902016002R00 - NRC Website

LER 16-002-00 for Watts Bar, Unit 1, Regarding Technical Specification Action Not Met for Inoperable Containment Isolation Valve

ML16125A056
Person / Time
Site:	Watts Bar
Issue date:	05/04/2016
From:	Simmons P Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LER 16-002-00
Download: ML16125A056 (7)

comments regarding burden estimate to the FOIA, Privacy and Information Collections Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by internet e-mail to 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

2016 - 00 002

I. PLANT OPERATING CONDITIONS BEFORE THE EVENT

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

II. DESCRIPTION OF EVENT

A. Event

entered Technical Specification (TS) 3.6.3, Containment Isolation Valves, Condition A for a containment isolation valve associated with the ice condenser glycol system {El IS:BC} being inoperable. During a containment walkdown, leakage was found on valve 1-FCV-61-122, Glycol Cooled Floor Return Header Isolation {EIIS:FCV} and the valve was declared inoperable. TS 3.6.3 Condition A requires that a penetration flow path with one containment isolation valve inoperable to be isolated by use of at least one closed and de-activated automatic valve, closed manual valve, blind flange, or check valve with flow through the valve within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. The penetration associated with this containment isolation valve was not isolated until 2113 EST on March 5, 2016.

Because the action specified by TS 3.6.3 was not completed within four hours, this condition is reportable as an operation or condition prohibited by TS per 10 CFR 50.73(a)(2)(i)(B).

B. Inoperable Structures, Components, or Systems that Contributed to the Event No inoperable structures, components, or systems contributed to this event.

C. Dates and Approximate Times of Occurrences Date Time Event 3/05/16 1512 EST 1-FCV-61-122, Glycol Cooled Floor Return Header Isolation declared inoperable.

3/05/16 1935 EST Licensing requested to verify invoking the TS LCO 3.6.3 note allowing the CIV path to remain open with administrative controls in place and determine acceptable time frame for "intermittent.

3/05/16 2113 EST 1-FCV-61-110 was closed and deactivated, isolating the penetration flowpath.

3/05/16 2142 EST Licensing formal interpretation of TS 3.6.3 compliance entered into operating logs.

D. Manufacturer and Model Number of Components that Failed While a leak on valve 1-FCV-61-122 caused the plant to enter TS 3.6.3 Condition A, it was not the cause of personnel failing to comply with the requirements of the Technical Specifications.

E. Other Systems or Secondary Functions Affected

There were no systems or secondary functions affected by this event.

comments regarding burden estimate to the FOIA, Privacy and Information Collections Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by Internet e-mail to 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

2016 - 00 002 F. Method of discovery of each Component or System Failure or Procedural Error While a component issue was involved in this report, it did not cause the condition prohibited by Technical Specifications G. Failure Mode and Effect of Each Failed Component While a leak on valve 1-FCV-61-122 caused the plant to enter TS 3.6.3 Condition A, it was not the cause of personnel failing to comply with the requirements of the Technical Specifications.

H. Operator Actions

Upon receiving clarification of the expectations associated with the TS 3.6.3 Note, operations properly isolated the impacted penetration.

I. Automatically and Manually Initiated Safety System Responses There were no automatic or manual system responses associated with this event.

III. CAUSE OF THE EVENT

A. The cause of each component or system failure or personnel error, if known.

This event was the result of an incorrect understanding of how to comply with the Note associated with TS 3.6.3.

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

The cause of this event was an incorrect understanding of how to comply with the Note associated with TS 3.6.3.

IV. ANALYSIS OF THE EVENT

TS LCO 3.6.3 Condition A, Containment Isolation valves, required the penetration associated with valve 1-FCV-61-122 to be isolated within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. Note 1 associated with TS 3.6.3 allows for a penetration flow path to be unisolated intermittently under administrative controls, such as to perform testing after maintenance. Operations stationed a dedicated operator in accordance with TS LCO 3.6.3 Note 1, but did not isolate the valve. This was based on an understanding that by invoking Note 1 with a dedicated operator stationed to isolate the flowpath that this met the intent of shutting the valve for the 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> time requirement for the action statement of the LCO. Upon being informed by site licensing that this reading of the TS Note was incorrect, the valve was isolated.

comments regarding burden estimate to the FOIA, Privacy and Information Collections Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by internet e-mail to 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

2016 - 00 002

V. ASSESSMENT OF SAFETY CONSEQUENCES

A. Availability of systems or components that could have performed the same function as the components and systems that failed during the event There were no safety system failures associated during this event. In the event a Loss of Coolant Accident (LOCA) had occurred during the inoperability of valve 1-FCV-61-122, the remaining containment isolation valve (1-FCV-61-110) for this penetration was capable of closing and isolating this 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 Corrective Action Program and is being tracked under condition report 1146157.

A. Immediate Corrective Actions

Upon identifying the correct requirements to implement TS 3.6.3 Condition A, the impacted penetration was properly isolated.

B. Corrective Actions to Prevent Recurrence

A shift order defining the correct response when entering TS 3.6.3 Condition A was provided to the operating staff. This issue will be a topic of future operations training.

VII. ADDITIONAL INFORMATION

A. Previous similar events at the same plant

This LER involves an incorrect understanding by operations personnel in how to apply Technical Specification requirements. No similar event was identified with the same causal basis.

B. Additional Information

None.

comments regarding burden estimate to the FOIA, Privacy and Information Collections Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by intemet e-mail to 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.

C. Safety System Functional Failure Consideration

This condition did not result in a safety system functional failure.

D. Scrams with Complications Consideration There was no scram associated with this report.

VIII. COMMITMENTS

None.