ML17272A019

Watts Bar, Unit 1 - Technical Specification (TS) 5.9.8 - Post Accident Monitoring System (Pams) Report

ML17272A019
Person / Time
Site:	Watts Bar
Issue date:	09/29/2017
From:	Simmons P Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML17272A019 (3)

Text

Tennessee Valley Authority, Post Office Box 2000, Spring City, Tennessee 37381 September 29,2017 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 August 16,2017, containment high range radiation monitor 1-RM-90-272 was declared inoperable.

On September 15, 2017, 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) 365-7720.Respectfully, Paul Simmons Site Vice President Watts Bar Nuclear Plant Enclosure cc: See Page 2 U.S. Nuclear Regulatory Commission Page 2 September 29,2017 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 l2, "Containment Radiation (High Range)," requires two monitors for upper containment and two monitors for lower containment.

On August 16,2017, 1-RM-90-272, one of the two upper containment area radiation monitors was declared inoperable when its green operable light would not remain lit.TS 3.3.3 Limiting 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.On-line efforts to repair this indication were unsuccessful prior to exceeding the 30 day period of inoperability specified by TS 3.3.3. Parts to correct this issue were obtained after the 30 day period expired.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 Monitorino A prompt determination of operability performed by site engineering determined the monitor will perform its safety function with the green operational light not in service provided that the integrated computer system (lCS) alarm setpoint for 1-RM-90-272is active (audible) for Operations response.

ln addition, a second upper containment high range radiation monitor remains operable and capable of providing indication during an accident.Gause of lnoperabilitv The issue is associated with a failed subcomponent within the ratemeter for 1-RM-90-272.

Actions and Schedule to Restore lnstrumentation Function to Ooerable Condition Repairs to 1-RM-90-272were performed and this containment radiation monitor was returned to a fully operable status on September 28, 2017.