ML18242A038

Technical Specification (TS) 5.9.8 - Post Accident Monitoring System (Pams) Report

ML18242A038
Person / Time
Site:	Watts Bar
Issue date:	08/30/2018
From:	Simmons P Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML18242A038 (3)

Text

Tennessee Valley Authority, Post Office Box 2000, Spring City, Tennessee 37381 August 30, 2018 10 cFR 50 4 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C . 20555-0001 Watts Bar Nuclear Plant, Unit 1 Facility Operating License No. NPF-90 NRC Docket No. 50-390

Subject:

Technical specification (TS) 5.9.8 - Post Accident Monitoring system (PAMS) Report The program requirements for the Watts Bar Nuclear Plant WBN) Post Accident Monitoring System (PAMS) requires a report to be submitted within 14 days when Condition B of Technical Specification (TS) Limiting Condition for Operation 3.3.3, "Post Accident Monitoring (PAM) lnstrumentation," is entered. On July 30, 2018, the containment isolation valve indication for steam generator blowdown valve 1-FCV-1-7 was determined to be inoperable. On August 29,2018, WBN entered TS 3.3.3 Condition B for this event when the inoperable condition had been present for 30 days, requiring a Special Report to the NRC. This special report is provided in the Enclosure.

There are no new regulatory commitments in this letter. Please direct any questions concerning this matter to Kim Hulvey, wBN Licensing Manager, at (423) 36s-7720.

Respectfully, Paul Simmons Site Vice President Watts Bar Nuclear Plant Enclosure cc: See Page 2

U.S. Nuclear Regulatory Commission Page 2 August 30, 2018 cc (Enclosure):

NRC Regional Administrator - Region Il NRC Senior Resident lnspector - Watts Bar Nuclear Plant NRC Project Manager - watts Bar Nuclear Plant

Enclosure Technical Specification 5.9.8 PAMS Report Backqround The Watts Bar Nuclear Plant WBN) Technical Specification (TS) 3.3.3, "Post Accident Monitoring (PAM) lnstrumentation,'specifies the operability requirements for PAM instrumentation. TS Table 3.3.3-1, Function 11, 'Containment lsolation Valve Position,"

requires two operable indication channels per penetration flow path. On July 30, 2018, the outboard Steam Generator Blowdown (SGBD) isolation valve 1-FCV-1-7 on WBN Unit 1 was determined to have inoperable valve position indication. During performance of the 18 month remote shutdown transfer switch verification, hand switch 1-HS-'l-7/181 was taken to the open position while starting Motor Driven Auxiliary Feedwater Pump 1B to maintain SGBD in service. While in this configuration, the indicating lights for 1-FCV-1-7 went from Red only to dual Red and Green indication and continued to show dual indication when the valve hand switch was released and returned to the auto position.

TS 3.3.3 Llmiting Condition for Operation (LCO) Condition A allows a single indication channel to be inoperable for 30 days. lf the indication channel is not restored within 30 days, LCO Condition B is entered, which requires action in accordance with TS 5.9.8 to be taken immediately. TS 5.9.8 requires a report to be submitted to the Nuclear Regulatory Commission within 14 days.

The valve identified is located in an area that exceeds '100 degrees Fahrenheit, and allowable personnel stay times are limited. For reasons of personnel safety, corrective actions will be not be performed until the WBN Unit 1 outage in September 2018.

This report outlines the preplanned alternate method of monitoring, the cause of inoperability, and the plans and schedule for restoring the instrumentation channels of the Function to OPERABLE status.

Preplanned Alternate Method of Monitorinq With the outboard SGBD isolation valve indication inoperable, operations personnelwill use blowdown flow indication and indication of closure of 1-FCV-1-181, the inboard blowdown isolation valve, to validate blowdown isolation. An operator will be dedicated to close 1-FCV-1-7 if required.

Cause of lnoperabilitv The outboard SGBD isolation valves are Target Rock solenoid valves with reed switches to support position indication. The valve identified is located in an area that exceeds 100 degrees Fahrenheit, and allowable personnel stay times are limited. For reasons of personnel safety, corrective actions will be not be performed untilthe WBN Unit 1 outage in September 2018.

Actions and Schedule to Restore lnstrumentation Function to Operable Condition Actions to restore the outboard SGBD isolation valve indication will be performed during the next unit 1 refueling outage scheduled to start in September 2018.