ENS 48506

From kanterella

Jump to navigation Jump to search

v t e ENS Event
06:45 Sep 18, 2012
Title	60-Day Optional Telephonic Notification of Invalid Actuation of Containment Isolation Signals
Event Description	This 60-day telephone notification is being made per the reporting requirements specified by 10 CFR 50.73(a)(2)(iv)(A) and 10 CFR 50.73(a)(1) to describe an invalid actuation of a general containment isolation signal affecting more than one system. On September 18, 2012, at 0045 hours5.208333e-4 days <br />0.0125 hours <br />7.440476e-5 weeks <br />1.71225e-5 months <br /> Central Daylight Time (CDT), during performance of surveillance procedure 1-SR-3.3.6.2.3(B), Reactor/Refueling Zone Ventilation Radiation Monitor 1-RM-90-141/143 Calibration and Functional Test, a Primary Containment Isolation System (PCIS) partial Group 6 isolation occurred. The partial Group 6 isolation caused the initiation of Standby Gas Treatment (SBGT) subsystems 'A' and 'B' and Control Room Emergency Ventilation (CREV) subsystem 'A', and the isolation of the Unit 1 H2O2 analyzer and the 1-RM-90-256 Continuous Air Monitor (CAM). Due to the isolation of the 1-RM-90-256 CAM, Operations personnel declared the drywall CAM inoperable and entered Technical Specifications (TS) Limiting Condition for Operation (LCO) 3.4.5 Condition B. Plant conditions which initiate PCIS Group 6 actuations are Reactor Vessel Low Water Level (Level 3), High Drywall Pressure, and Reactor Building Ventilation Exhaust High Radiation (Reactor Zone or Refuel Zone). At the time of the event, these conditions did not exist, therefore, the partial actuations were invalid. The affected equipment responded as designed. On September 18, 2012, at 0123 hours0.00142 days <br />0.0342 hours <br />2.03373e-4 weeks <br />4.68015e-5 months <br /> CDT, Operations personnel commenced restoring the affected systems to normal. At 0132 hours0.00153 days <br />0.0367 hours <br />2.18254e-4 weeks <br />5.0226e-5 months <br /> CDT, the 1-RM-90-256 CAM was returned to service, the SBGT subsystems 'A' and 'B' were secured, and TS LCO 3.4.5.B was exited. At 0133 hours0.00154 days <br />0.0369 hours <br />2.199074e-4 weeks <br />5.06065e-5 months <br /> CDT, the CREV subsystem 'A' was secured and at 0138 hours0.0016 days <br />0.0383 hours <br />2.281746e-4 weeks <br />5.2509e-5 months <br /> CDT, the Unit 1 hours1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> analyzer was returned to service. This condition was the result of improper test setup during performance of 1-SR-3.3.6.2.3(B). It was determined that a jumper installed during the performance of 1-SR-3.3.6.2.3(B) to prevent an invalid actuation was not installed correctly. When the detector lead was lifted, an isolation signal was received. The surveillance procedure was stopped and the equipment was restored to pre-test condition. There were no safety consequences or impact to the health and safety of the public as a result of this event. This event was entered into the Corrective Action Program as Problem Evaluation Report 611238. The NRC Resident Inspector has been notified of this event.

ENS 48506 +/-
Where
Browns Ferry Alabama (NRC Region 2)
Reporting

10 CFR 50.73(a)(1), Submit an LER, Invalid Actuation
Time - Person (Reporting Time:+1375.92 h57.33 days <br />8.19 weeks <br />1.885 months <br />)
Opened:	Rodney Nacoste 15:40 Nov 14, 2012
NRC Officer:	Howie Crouch
Last Updated:	Nov 14, 2012
48506 - NRC Website Loading map...
v • d • e

v t e Emergency Notification System
Browns Ferry with 10 CFR 50.73(a)(1), Submit an LER
WEEKMONTHYEAR		60-Day Optional Telephonic Notification of an Invalid Actuation of a General Containment Isolation Signal Affecting More than One System	60-Day Optional Telephonic Notification of an Invalid Specified System Actuation 2026-02-04T04:15:00 [Table view]
[ENS list for Browns Ferry]

Retrieved from "https://kanterella.com/w/index.php?title=ENS_48506&oldid=423479"