05000260/LER-1983-074-03, /03X-3:on 831110,during HPCI Startup,Rupture Occurred in Turbine Exhaust Inner Rupture Diaphragm After Isolation,Due to Auto Initiation Signal.Cause Unknown.Addl Testing to Be Performed
05000260/LER-1983-063-01, Discovered 2-LT-85-45A (West Side SDIV Level Transmitter) Did Not Initiate Trip When SDIV Level Exceeded 50-gallon Setpoint.Caused by Small Puncture Holes in Module Diaphragm
05000296/LER-1983-059-01, /01T-0:on 831208,during Refueling outage,crack- Like Indication Detected.Caused by Intergranular Stress Corrosion Cracking on Weld DSHS-3-2.Head Spray Piping Will Be Removed Before Startup
05000260/LER-1983-074-01, /01T-0:on 831110,HPCI Sys Initiated,But Immediately Became Inoperable.Caused by Blown Turbine Exhaust Rupture Disc,Fike Model 16-CPV-CBT.Disc Replaced
05000260/LER-1983-061-01, /01T-0:on 831004,hydrogen Analyzers a & B Removed from Svc to Replace Pump Assembly After Notification from Manufacturer That Assemblies Would Not Perform Per Tech Spec.Caused by Mfg Deficiency
05000296/LER-1983-054-01, /01T-0:on 830919,during Refueling Outage,While Performing Leakage Test,Combined Leakage of MSIV Lines A,C & D Exceeded Limit.Caused by 26-inch Global Valve Leaking Past Main Seat.Valve Repaired
05000296/LER-1983-024-01, Mlhgr for Rod Withdrawal Error Scenario Exceeded 1% Plastic Strain Linear Heat Generation Rate Limit for Eight LTA Bundles.Caused by Lack of Communication Between GE Personnel
05000259/LER-1983-049-01, /01T-0:on 830811,while Performing Ultrasonic Insp of Core Spray,Rhr Head Spray & Reactor Water Cleanup Piping, crack-like Indications Detected & Confirmed on Welds.Caused by Intergranular Stress Corrosion Cracking
05000259/LER-1982-096-01, /01T-0:on 821206,during Startup,Control Rod 18-51 Double Notched from 08 to 12,resulting in Large Reactivity Insertion & Causing Reactor to Scram.Cause Attributed to Normal Degradation of Control Rod Drive Seals
05000259/LER-1983-036-01, /01T-0:on 830630,during Cycle 5 Refueling Outage, Seven of 13 two-stage Relief Valves Tested for as-found Set Pressure Initially Failed to Lift within Allowable 1% Tolerance.Cause Being Evaluated
05000296/LER-1983-051-01, /01T-0:on 830812,control Valve Fast Closure/Stop Valve Scram Bypass Pressure Switches PS-1-81A & B & PS-1-91A & B Operated Above Tech Spec Limit.Caused by Calibr Drift.Switches Recalibr
05000259/LER-1983-021-01, /01T-0:on 830424,130 Fuel Bundles Unloaded from Core Into high-density Spent Fuel Storage Rack (Hdsfsr) Did Not Have Required post-installation Boron Test.Caused by Personnel Failure to Verify Hdsfsr Acceptability
05000296/LER-1983-031-01, /01T-0:on 830520,while Performing SI 4.2.B-7, Pressure Switches 3-PS-3-74B Switches 1 & 2 & 3-PS-68-96 Switch 2 Had as-found Calibr Values Below Tech Spec Limits. Caused by Setpoint Drift.Switches Recalibr
05000296/LER-1983-008-01, /01T-0:on 830207,while Performing SI 4.1.A-7, Reactor Protection Sys Water Level Switches 3-LIS-3-203 B & D Switch 1 Found Out of Tolerance.Caused by Setpoint Drift. Barton Model 288 Switches Recalibr & Functionally Tested
05000259/LER-1982-099-01, /01T-0:on 821208,during Periodic Leak Detection Program,Weeping Leak Found in Cracked 1/2-inch Core Spray Sys Sample Connection Pipe.Caused by Fatigue Failure Induced by Vibration.Repairs Made
05000260/LER-1982-039-01, /01X-0:on 821204,during Fuel Outage,Level Switches LS-73-57A & 57B Found Inoperable.Caused by Stuck Robert Shaw Model 82798-C3 Level Switch Floats.Floats Freed & Level Switches Recalibr
05000296/LER-1982-037-01, During Instrumentation Calibr for Core Standby Cooling Sys Suppression Chamber, Calibr Valve on Level Switch LS-73-57A Found Open Rendering Switches Inoperable.Caused by Open Valve.Valve Closed
05000259/LER-1978-034-01, /01T-0 on 781205:during Refueling Outage 6 MSIVs Exceeded Leakage Limits.Caused by Degradation of Valve Seating Surfaces Thru Normal Oper
05000259/LER-1978-028-01, /01T-0 on 780919:Foxboro Model 610 Pwr Supplies Provided Under TVA Contact 75K11-8680 Were Not Seismically Qualified,Qualified Pwr Supplies Have Been Provided & Will Be Installed
05000259/LER-1982-075-01, /01T-0:on 820924,four Degraded Voltage Relays, Three Timers & One loss-of-voltage Relay Found to Be Outside Allowable Tech Spec Setpoint Range.Caused by Setpoint Drift. Relays Recalibr & Returned to Svc
05000296/LER-1982-036-01, /01T-0:on 820824,during Surveillance Instruction 4.1.A-14,pressure Switches PS-1-81A & B & PS-1-1-91B Operated Above Tech Spec Limits.Caused by Barksdale Model B2T A1255 Pressure Switch Calibr Drift.Switches Recalibr
05000259/LER-1982-054-01, /01T-0:on 820804,during Computer Analysis of Branch Lines for Suppression Chamber Attached Piping,Drywell & Torus Purge Sys Found to Have Branch Line Anchored to Floor.Caused by Design Deficiency.Anchor Design Changed
05000260/LER-1982-023-01, /01T-0:on 820723,equalizer Valve on Differential Pressure Switch 2-Pdis-73-1B three-valve Block Manifold Would Not Close,Rendering Switch Inoperable.Caused by Improperly Seated Valve Manifold Equalizer Valve
05000260/LER-1982-011-03, /03L-0:on 820215,during Operation,While Performing Chamber Water check,2-LI-64-66 Indicated Improper Torus & Level & Declared Inoperable.Caused by Instrument Drift & Possible Air in Ref Leg.Transmitter Calibr
05000296/LER-1981-074-01, /01T-0:on 811230,2-stage Relief Valves Initially Failed to Lift within Allowable Range During as-found Set Pressure Tests.Cause Under Evaluation.Valves Will Be Reset, Repaired & Retested Prior to Installation
05000296/LER-1981-029-03, Fire Protection Preaction Sprinkler Sys for Reactor Bldg Elevations 565-593 & 621 Found Isolated.Caused by Personnel Lack of Familiarity W/ Isolation Valve Operating Characteristics.Valve Opened
05000259/LER-1981-056-03, /03L-0:810930,while Performing Special Instructions 4.7.D.1B-2,closure Times for MSIVs 1-14,1-26, 1-37 & 1-51 Exceeded Time Limits.Cause Undetermined.Timing of hydro-line Operator Adjusted
05000259/LER-1982-079-01, /01T-0:on 821011,during Performance of SI 4.5.A.1.C,test Bypass Valves FCV-75-22 & FCV-75-50 Did Not Meet Required Closing Time.Caused by Variation in Torque Limit Switch Mechanism Settings.Valve Switches Reset
05000259/LER-1982-071-01, /01T-0:on 820909,HPCI Condensate Storage Tank Low Level Switches LS-73-56A & LS-73-56B Failed to Operate. Caused by Dirty & Corroded Level Switches Activating Plates. Plate Points Cleaned
05000259/LER-1983-020-01, /01T-0:on 830418,line A,B,C & D MSIVs Exceeded Allowable Leakage Rates.Caused by Deterioration of MSIV Seating Surfaces During Operation.Valves Will Be Repaired Prior to Startup & MSIV Improvement Program Implemented
05000296/LER-1980-058-03, /03L-0:on 801207,MSIV 1-14,1-15,1-26,1-27,1-37 & 1-38 & 1-51 Found Leaking.Caused by Seating Surface Deterioration Due to Normal Wear.Valves Repaired
05000259/LER-1981-016-01, /01T-0:on 810501,fire Pump Automatic Start Logic Found Inoperable During post-mod Tests.Caused by Wiring Being Removed from Terminal Points in Main Relay Panel 52. Permanent Wiring Replaced
05000260/LER-1981-019-01, /01T-0:on 810425,bypass Installed on Main Steam High Temp Isolation Relays to Control Unit Conditions for Maint on Ventilation Sys.Caused by Electrical Components Malfunction.Repairs Initiated & Ventilation Restored
05000259/LER-1981-009-01, /01T-0 on 810304,IE Info Notice 80-45 Evaluation Determined That Reactor Protection Sys for Units 2 & 3 Were Deficient Upon Loss of Power W/Subsequent Restoration.Caused by Design Deficiency.Caution Added to Instructions
05000259/LER-1980-039-01, /01T-0:on 800507,util Notified by GE That Qualification of Containment Atmospheric Monitoring Sys Hydrogen Sensors Has Not Been Demonstrated to Meet Purchase Specs.Operating Procedures & Instructions Changed
05000259/LER-1979-003-01, /01T-1 on 790120:during Cold Shutdown,Local Leak Rate Test Indicated Excessive Total Leakage.Caused by Leaking Valve Seating Surface in Eight Valves.Valves Repaired & Retested
05000259/LER-1979-001-01, /01T-0 on 790118:reactor Scrammed Due to High Flux Actuating Intermediate Range Monitor high-high Neutron Monitoring Circuit;Reactor Neared Criticality.Caused by Withdrawal of High Reactivity Worth Rod
05000259/LER-1979-032-01, /01T-0:on 791128,residual Heat Removal Supply to D Heat Exchanger Restraint R16 Determined Nonfunctional as Installed.Caused by Erroneous Application of Typical Hanger Design.Sys Will Function During Seismic Event
05000296/LER-2078-002, For Browns Ferry Nuclear Plant, Unit 3, Bendix Connectors of Type Used Inside Primary Containment Have Failed a Post-Aging Environmental Test at Wyle Laboratory Testing Facility
05000260/LER-2078-004, Relief Valve 2-1-5 Opened and Failed to Reseat During Steady State Operation
05000296/LER-2078-010, For Browns Ferry Nuclear Plant, Unit 3, Both RBM Channels Which Became Continuously Bypassed During Power Ascension
05000296/LER-2078-006, For Browns Ferry Nuclear Plant, Unit 3, Electrical Connector Carrying Thermocouple Circuits Monitoring Primary Containment Atmospheric Temperature Not Included as Part of Modification Which Qualified Connector Assemblies for Ac
05000259/LER-2078-205-01, Four Main Steam Isolation Valves Which Exceeded the Leakage Limits of Technical Specification 4.7.A.2.i While Performing Local Leak Rate Testing During Refueling
05000260/LER-1979-011-01, /01T-0 on 790526:while Pulling Control Rods,First Rod 26-27 in Group 3 Was Inadvertently Withdrawn Three Notches.Caused by Unexplained Factors.Procedures Were Revised
05000296/LER-1978-025-01, /01T-0 on 780917:during refueling,4 Mstvs Exceeded Leakage Limits.Defective Valves Will Be Repaired & Retested
05000260/LER-1980-042-03, LER:80-042/03L-0:on 800929,during Leak Rate Testing on Main Steam Isolation Valves,Valves 1-14,1-15,1-26 & 1-52 Exceeded Allowable Leakage Rate.Caused by Seating Surface Deterioration.Valves Repaired & Retested
05000260/LER-1978-016-01, /01T-0:on 780930,cracking Discovered in 1-inch Instrument Line & 3/4-inch Bonnet Vent Line on FCV-68-1. Cause Undetermined
05000296/LER-1981-029-01, /01T-0:on 810616,fire Protection Preaction Sprinkler Sys for Reactor Bldg Elevations 565,593 & 621 Were Found Isolated.Caused by Personnel Error.Valve Opened. Personnel Familiarized W/Isolation Valve Operation
05000260/LER-1983-004-01, /01T-0:on 830220,reactor Water Level Switch Setpoints Discovered out-of-tolerance.Caused by Setpoint Drift in Barton 288 Switches.Switches Recalibr & Will Be Replaced Per DCR 1398
05000259/LER-1983-073-01, /01T-0:on 831231,reactor Coolant Sample Indicated Chloride Concentration of 525 Ppb & Conductivity & Offgas Radiation Level Increased While Ph Decreased.Caused by Resin Intrusion Into Reactor Vessel.Trap Replaced
05000259/LER-1983-009-01, Design Review of Emergency Diesel Generator Engine Coolers Showed Coolers May Not Be Able to Maintain Cooling Water Below Hot Setpoint. Caused by Design Error.Setpoint Raised