05000296/LER-1981-019-01, /01T-0:on 810423,upper & Lower Gland Seal Condenser Head Gaskets Blew Upon Initiation of HPCI Sys. Caused by Gaskets Stretched Out of Place Due to Overpressurization of Condenser Tube Side.Gaskets Replaced
05000296/LER-1981-018-03, /03L-0:on 810414,core Max Fraction of Limiting Power Density Found Exceeding Tech Spec Limit Following Local Power Range Monitor Calibr.Possibly Caused by Instrument Drift.Monitor Recalibr within Tech Spec Limits
05000296/LER-1980-051-03, /03L-0:on 801116,redundant Drywell Hydrogen Sensor 3-H2E-76-39A Would Not Calibr to Ref Gas.Sensor Declared Inoperative.Caused by Sensor 47E226428G2 Failure.Unit Shut Down for Refueling 801123 & Sys Replaced
05000259/LER-1980-090-03, /03L-1:on 801210,during Normal Operation, Continuous Air Monitor for Reactor/Turbine Ventilation Exhaust Declared Inoperable.Caused by Iodine Channel Indication Downscale.Instrument Repaired
05000260/LER-1978-014-03, HPCI Sys Sustained Damage to High Pressure Pump & Reduction Gear Set Which Drives Low Pressure Pump.Caused by Failure to Open Valve in Lubrication Oil Line.Instruction Revised
05000260/LER-1983-082-03, /03L-0:on 831223,during Normal Operation, Recirculation Pump 2A Tripped Due to Actuation of Relay 2A-K21A Neutral Overvoltage.Caused by Gouged Insulation on Phase C Conductor in Cable 2PP1005
05000259/LER-1983-052-03, /03L-0:on 830912,while Performing Surveillance Instruction 4.11.C.3 & 4 on Reactor Bldg Elevation 593 Fixed Spray Zone 1E Heat Detector Relay Discovered Inoperable. Caused by Random Failure.Relay Replaced
05000296/LER-1982-067-03, /03L-0:on 821225,coupling Unit on Diesel Generator C Lube Oil Pump Found Broken.Caused by Deterioration of Coupling Spider Due to Normal Svc.Pump Mfg by Viking & Coupling by Lovejoy.Coupling Replaced
05000260/LER-1983-078-03, /03L-0:on 831207,while Isolating Valve 1-FCV-74-66 for Maint,Rhr Crosstie Connection Isolated.Caused by Maint Activities on RHR Sys on Units 1 & 3.Crosstie Connection Restored
05000260/LER-1983-073-03, /03L-0:on 831128,percent Power/Core Max Limiting Power Density Ratio Found Less than Tech Spec Limit.Caused by Xenon Transient Due to Reactor Scram & Pulling of Rods to Prescram Pattern.Rods Inserted
05000260/LER-1983-072-03, /03L-0:on 831108,during Performance of High Flow Steam Line Calibr Functional test,Pdis-1-36B,1-13B & 1-050B Experienced Setpoint Drift.Barton Model 278 Pressure Switches Also Experienced Setpoint Drift
05000259/LER-1983-065-03, /03L-0:on 831107,high Water Level Surveillance in Scram Discharge Tank Not Performed in Compliance W/Tech Spec Table 3.1.A.Caused by Failure to Include Surveillance Instruction in Master Schedule
05000260/LER-1983-066-31, /03L-0:on 831031,operator Observed Low Flow Alarm in Hydrogen Monitor B (H2AN-76-104).Caused by Moisture Collecting in Sample Lines.Lines Blown Down
05000259/LER-1983-063-03, /03L-0:on 831102,flow Distribution Through Standby Gas Treatment Train B Failed Acceptance Criteria.Caused by Accumulation of Sand in Moisture Separator.Moisture Separator Repaired
05000260/LER-1983-071-03, /03L-0:on 831104,while Performing Surveillance Insp 4.2.B-7,2-PS-3-74A Pressure Switch 1 Had as-found Setpoint of 214.43 Psig.Caused by Calibr Drift.Barksdale B 2T-M12SS Switch Recalibr
05000260/LER-1983-070-03, /03L-0:on 831103,downstream HEPA MSA Ask 1743-1217 Filters in Standby Gas Treatment Train C Measured 98% DOP Removal.Caused by Degradation & Wear of Filters Through Normal Use.Filters Replaced
05000260/LER-1983-075-03, /03L-0:on 831116,during Startup,Following Reactor Scram,R Factor Found Below R Setpoint of 1.0.Caused by Xenon Transient Due to Reactor Scram & Pulling of Rods to Prescram Pattern.Rods Inserted
05000260/LER-1983-065-03, /03L-0:on 831013,reactor Protective Sys Channel a Manually Tripped W/O Performing Functional Test on Scram Discharge Instrument Vol Channel B.Caused by Personnel Oversight.Tech Spec Criteria Stressed
05000259/LER-1983-060-03, /03L-0:on 831018,containment Atmosphere Dilution Tank a Nitrogen Level Decreased to Below 74% Full.Caused by Leaks in Velan Valves.Vendor Requested to Replenish Lost Nitrogen Vol on 831017
05000296/LER-1983-058-03, /03L-0:on 831017,during Refueling Outage,Drywell Temp Recorder 3-TR-64-52 Found Out of Calibr.Caused by Instrument Drift.Recorder Calibr,Tested & Returned to Svc
05000260/LER-1983-068-03, /03L-0:on 831021,during Normal Operation,Rhr Loop II Flow Instrumentation Pegged Upscale.Caused by Short in GE Type 531 Recorder Which Drove FR-74-64 & FI-74-64 Upscale Causing Fuse to Blow.Fuse Replaced
05000260/LER-1983-064-03, /03L-0:on 831016,during Normal Operation,Operator Observed RHR Loop II Flow Instrumentation Pegged Upscale. Caused by Defective Slidewire in Recorder FR-74-64.Recorder Replaced
05000296/LER-1983-057-03, /03L-0:on 831010,observed That More than One Rod Could Be Selected W/O Use of One Rod Permissive Bypass Which Violates Tech Spec 3.10.A.1.Caused by Stuck Reed Relay on Relay Logic Card GE 193B1441G-1
05000259/LER-1983-058-03, /03L-0:on 831007,during Emergency Cooling Water Pipe Replacement,Check Valve 1-67-660,Daniels Series 1600, Discovered Installed Backwards.Sys Modified W/New Piping & Valves
05000260/LER-1983-062-03, /03L-0:on 831004,while Performing Surveillance Instruction 4.9.A.1(a),second Starter on Diesel Generator C Engaged W/Diesel While Operating at 900 Rpm.Caused by Air Leak in Solenoid Valve.New Valve Installed
05000259/LER-1983-056-03, /03L-0:on 831003,radiochemical Lab Personnel Discovered Inlet Sample Hose CAM O-90-252 (Common) Disconnected.Caused by Personnel Moving Hose for Unknown Reasons.Sample Hose Reconnected
05000296/LER-1983-056-03, /03L-0:on 830929,pressure Switch PS-3-204D Found W/Setpoint of 1,125 Psig,Exceeding Trip Level Setting of 1,120 Psig.Caused by Setpoint Drift.Switch Recalibr,Tested & Returned to Svc
05000260/LER-1983-060-03, /03L-0:on 830930,test Bypass Valve FCV-75-50 Exceeded Closure Limit.Caused by Close Tolerance of Valve Limit Switch & Tight Valve Packing.Switch Adjusted
05000260/LER-1983-059-03, /03L-0:on 830929,drywell Equipment Drain Sump Pump Excessive Operation Annunciation Discovered Alarming Frequently.Caused by Failure of Cycl-flex 60-minute Timer. Timer Replaced & Calibr
05000259/LER-1983-054-03, /03L-0:on 830927,review of Records Indicated That During 7 Months Prior to Shutdown,Addl Samples Required by Tech Spec 4.6.B.6 Not Taken.Caused by Lack of Administrative Controls
05000259/LER-1983-055-03, /03L-0:on 830901,discovered Core Spray Test Bypass Valves FCV-75-22 & 50 Not Tested During Aug.Caused by Missing Test When Core Spray Sys Slow Test Frequency Changed to Quarterly.Operability Test Revised
05000260/LER-1983-057-03, /03L-0:on 830923,while Performing S.I.4.9.A.4.b, Undervoltage Start of Diesel Generator,Diesel Generator 1A Oversped & Tripped.Caused by Electronic Governor Inhibited by Logic Breaker Malfunction
05000260/LER-1983-054-03, /03L-0:on 830916,west Side Scram Discharge Vol High Water Level Switch LS-85-45C Would Not Reset Following Scram.Caused by Setpoint Drift.Switch Recalibr
05000259/LER-1983-051-03, /03L-0:on 830824,during Refueling,Continuous Air Monitor 1-90-250 Declared Inoperable Due to Broken Drive Belt.Caused by Normal Wear Due to Continuous Operation.Belt Replaced
05000260/LER-1983-050-03, /03L-0:on 830823,while Performing SI4.2.B-57,RHR Pump 2C Cooler Fan Would Not Operate.Caused by Tripping of Overload Relay,Ge Model CR124C028.Overload Relay Reset & Surveillance Instruction Completed
05000296/LER-1983-052-03, /03L-0:on 830816,diesel Generator 3ED Failed to Reach Rated Speed on Automatic Start.Caused by Failed Woodward Governor Microswitch 11SM3-T.Switch Replaced.Diesel Generator Returned to Svc
05000260/LER-1983-033-03, Following Rod Adjustment & Preconditioning,Linear Heat Generation Rate & MAPLHGR Greater than Tech Spec Limits.Caused by Xenon Transient.Core Flow Reduced
05000259/LER-1983-071-03, /03L-0:on 831212,analyst Discovered Broken Vacuum Pump Belt on Reactor & Turbine Vent Monitor 1-RM-90-250. Caused by Normal Wear Due to Continuous Operation.Std V-belt for Schwitzer Model 325 Air Pump Replaced
05000296/LER-1983-045-03, /03L-0:on 830802,w/unit at 97% Power,Hydrogen Analyzer B Inoperable Due to Loss of Flow.Caused by Moisture in Sample Lines.Lines Blown Down & Dried.Sys Returned to Svc
05000259/LER-1983-050-03, /03L-0:on 830815,while Performing Surveillance Instruction 4.2.B-45,relay 10A-K34A Found to Operate at 8.2 & Relay 10A-K75B Found to Operate at 25.87 S.Caused by Setpoint Drift.Relays Recalibr
05000259/LER-1983-046-03, /03L-0:on 830726,during Routine Insp,Inspector Noted Standby Gas Treatment Train B Inoperable.Caused by Type Thed 136090 GE Molded Case Breaker Tripping.Breaker Reset
05000260/LER-1983-049-03, /03L-0:on 830725,while Performing Surveillance Instruction 4.2.B-60,core Spray Ne Room Cooler Fan Would Not Operate.Caused by Tripped Overload Relays in Full Voltage Nonreversing Magnetic Starter.Relays Replaced
05000260/LER-1983-083-03, /03L-0:on 831229,during Normal Operation,Hydrogen Analyzer B Hydrogen Sample Inlet Pump Discovered Inoperable. Caused by Seized Bearing Due to Improper Bearing Clearance in Metal Bellows Corp Motor Pn 25626
05000260/LER-1983-047-03, /03L-0:on 830725,during Normal Operation,W/Hpci Removed from Svc to Calibr Tachometer,Hpci Rendered Inoperable.Caused by Wiring Error During Tachometer Calibr. Wires Reterminated.Procedure Revised
05000260/LER-1983-084-03, /03L-0:on 831229,strainer on Pump C3 Became Restricted by Debris & All Flow Lost to North Header.Caused by River Debris.Strainer Cleaned & Pump Returned to Operability
05000259/LER-1983-045-03, /03L-0:on 830713,insp Revealed Failure of Coupling on Lube Oil Circulating Pump on Diesel Generator 1A.Caused by Wear from Normal Svc.Procedure Changed to Require Annual Changeout
05000259/LER-1983-043-03, /03L-0:on 830716,control Room Emergency Ventilation Sys Unit B Control Arm on Damper Fco 31-152 Found Disconnected.Caused by Loose Control Arm to Damper Nut.Nut Tightened & Arm Reconnected
05000296/LER-1983-040-03, /03L-0:on 830630,one Relay on 4kV Shutdown Boards 3EA,C & D & Two Relays on 3EB Exceeded Tech Spec Limit.Caused by Setpoint Drift Due to Increase in Ambient Temp.Relays Recalibr
05000259/LER-1983-019-03, /03L-0:on 830410,smoke Detector XS-39-66XM Alarmed Due to Leakage of Water Into Detector.Source of Water Not Determined.Detector Replaced & Will Be Relocated to Avoid Leakage
05000259/LER-1983-074-03, /03L-0:on 831228,during Refueling,Degraded Flow Condition Discovered on Radiation Monitor 1-RM-90-250. Caused by Normal Wear & Degradation of Schwitzer Series 325 Sample Pump.Pump Replaced
05000259/LER-1983-002-03, /03L-0:on 830117,during Surveillance Insp,Control Rod 10-39 Failed to Operate at Position 46.Probably Caused by Crud Accumulation in Valve Flow Orifice.Insert Directional Control Valve Replaced
05000260/LER-1983-001-03, /03L-0:on 830128,interlock Providing Rod Withdrawal Block Inoperable When Refuel Platform Moved Over Core.Caused by Failure of Limit Switch 2 Due to Stuck Plunger
05000259/LER-1982-098-03, /03L-0:on 821205,0-90-252 Radwaste Continuous Air Monitor Taken Out of Svc for 7.5 H to Repair Particulate Detector.Caused by Torn Mylar Film Covering Detector.Mylar Film Replaced
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
05000260/LER-1982-037-03, /03L-0:on 821122,while Performing Local Leak Rate Tests During Refueling Outage,Total as-found Leakage from Primary Containment Found Greater than Allowable,Per Tech Spec 4.7.A.2.g.Caused by Deterioration of Valve Seating
05000260/LER-1983-079-03, /03L-0:on 831212,discovered That Surveillance Instruction 4.2.B-1, Instrumentation That Initiates or Controls Core Standby Cooling Sys,Reactor Low Water Level, Not Performed within Max Frequency Interval
05000296/LER-1983-050-03, /03L-0:on 830809,reactor Bldg Vacuum Breakers, Barton Model 289 Differential Pressure Switch,Operated at 0.511 Psid.Caused by Calibr Drift.Switch Recalibr
05000296/LER-1983-049-03, /03L-0:on 830808,indication on Indicator LI-64-54A Decreased 1.8 Inches W/No Actual Torus Water Level Change.Caused by Unstable Power Supply PX-64-54.Power Supply Replaced
05000260/LER-1983-022-03, /03L-0:on 830503,scram Discharge Vol Scram Switch Failed to Operate.Reactor Protection Sys Logic Switch Tripped Upon Actuation.Caused by Magnetrol Model Switch Drift Outside Operating Band.Switch Adjusted
05000260/LER-1983-037-03, /03L-0:on 830705,increased Vibration & Motor Noise Found Emanating from Rmov Board Motor Generator Set 2EA. Caused by Worn Inboard/Outboard Bearings on Drive Motor. Bearings Replaced & Greased
05000260/LER-1983-036-03, /03L-0:on 830704,alarm Signal Detected on Reactor Bldg Elevation 593 Fire Protection Panel 2-25-311,Zone 2B, Heat Detector TE-39-46B & Could Have Masked Signals from Other Detectors.Caused by Bent Heat Detector
05000259/LER-1983-042-03, /03L-0:on 830629,reactor Bldg Elevation 621 Fire Protection Panel 1-25-303,Zone S,W & X Trouble Alarm Sounded.Caused by Spring Loaded 8A Fuse Holder Releasing. Fuse & Fuse Holder Repaired
05000260/LER-1983-035-03, /03L-0:on 830621,during Local Power Range Monitor Calibr,Calculated R Factor,Maplhgr & Linear Heat Generation Rate Limits Exceeded.Caused by Uncalibr Range Monitor Distribution Due to Set Up of New Rod Pattern
05000296/LER-1983-037-03, /03L-0:on 830617,during Normal steady-state Operation,Charging Water for RHR & Core Spray Switched from Condensate Head Tank to PSC Head Tank W/Charging Water Pressure Falling to 42 Psig.Sys Restored
05000259/LER-1983-032-03, /03L-0:on 830612,during Refueling Outage,Trouble Alarm Came in for Control Bay Elevation 593 Fire Protection Panel 1-25-325,zone 14.Caused by Power Loss to Some Smoke Detectors Due to Loose Wires
05000259/LER-1983-030-03, /03L-0:on 830612,during Refueling Outage,Stack Gas Sample Pump B Tripped Making Both Stack Monitoring Channels Inoperable.Caused by Overcurrent.Pump B Replaced.Failures Being Investigated
05000260/LER-1983-034-03, /03L-0:on 830615,during Normal Operation,Hpci Sys Declared Inoperable.Caused by Blown Inverter Fuse F1. Fuse Replaced.Failure Considered Random
05000296/LER-1983-036-03, /03L-0:on 830618,two Control Rods Indicated Uncoupled by Rod Overtravel Alarm.Caused by Disconnected Inner Filter,Damaged Spud &/Or Crud Accumulation.Control Rod Electrically Disarmed
05000296/LER-1983-043-03, /03L-0:on 830727,CAM3-90-256 Removed from Svc to Replace Sample Pump.Caused by Sample Pump Nearing End of Normal Svc Life.Sample Pump Replaced
05000296/LER-1983-041-03, /03L-0:on 830719,during Normal Operations,Control Rod Exercise SI 4.3.A.2 Not Performed within Required Schedule.Caused by Personnel Error.Personnel Counseled
05000260/LER-1983-041-03, /03L-0:on 830721,following Preconditioning Operations,Tech Spec Limit for Linear Heat Generation Rate Exceeded in Four Nodes.Caused by Insufficient Communication Between Operators During Flow Increases
05000260/LER-1983-044-03, /03L-0:on 830712,during Performance of 4.2.B-26, Level Switches LS-73-56A & B Mfg by Robertshaw Failed to Operate Properly.Caused by Dirt in Mechanical Linkage. Switches Cleaned
05000259/LER-1983-041-03, /03L-0:on 830720,control Room Emergency Ventilation Sys B Failed to Achieve Flowrate Required by Tech Spec.Caused by Partially Closed Manual Damper Due to Wing Nut Loosened by Vibration
05000260/LER-1983-043-03, /03L-0:on 830720,during Transient Operation, Following Control Rod Sequence Exchange,R Calculation Less than R Setpoint.Caused by Xenon Transient W/Operation Closer to Thermal Limits.Control Rods Repositioned
05000260/LER-1983-039-03, /03L-0:on 830716,during Transient Operation, Following Control Rod Sequence Exchange & Scram Testing, Program P1 Indicated R Calculated Less than R Setpoint. Caused by Failure of TIP Machine Indexer D
05000260/LER-1983-009-03, /03L-0:on 830319,HPCI Turbine Failed Due to Erratic Flow Controller.Caused by Trapped Air in Hydraulic Oil Control Sys Due to Maint Work
05000259/LER-1983-015-03, /03L-0:on 830310,temp Switch TS-71-2L Operated at 2049F,exceeding Tech Spec Requirements.Caused by Temp Switch Calibr Drift.Switch Replaced,Functionally Tested & Returned to Svc
05000259/LER-1983-014-03, /03L-0:on 830310,while Performing Primary Containment Isolation Valve Operability Test,Drywell Equipment Drain Isolation Valve Closed in 45 S,Exceeding Limit.Caused by Oily,Gummy Film Covering Internals
05000296/LER-1983-016-03, /03L-0:on 830302,during Normal Operation,Reactor Water Level Indicator LI-3-46A Observed to Be Fluctuating Erratically & Declared Inoperable.Caused by Calibr Drift. Indicator Replaced
05000296/LER-1983-015-03, /03L-0:on 830225,during Monthly Vibration Tests on 480-volt Reactor Motor Operator Valve Board MG Sets,High Readings Detected on Coupling of 3EN Motor Generator Set. Caused by Damage from Wear During Operation
05000260/LER-1983-024-03, /03L-0:on 830515,recirculation Pump 2A Tripped After Isolation Valve 2-24-744 Failed Closed.Caused by Sheared Coupling Pins.Crane Model XP-3600 Valve Repaired & Pump Returned to Svc
05000260/LER-1983-026-03, /03L-0:on 830521,during Rod Sequence Exchange, Calculated R Factor Less than R Setpoint.Caused by R Factor Calculated Out During Power Shaping Rod Moves.Rod Pattern Adjusted & Verified
05000260/LER-1983-027-03, /03L-0:on 830520,differential Pressure Switch for Pressure Suppression chamber-reactor Bldg Vacuum Breakers Found Operating Above Tech Spec Limits.Caused by Switch Drift.Switch 2-PDIS-64-20 Recalibr
05000296/LER-1983-030-03, /03L-0:on 830504,hydrogen Analyzer B Removed from Svc to Replace Defective Hydrogen Sample Inlet Pump Motor. Caused by Worn End Bell.Pump & Motor Assembly Replaced & SI 4.7.H Successfully Completed
05000260/LER-1983-023-03, /03L-0:on 830602,while Performing ST 4.1,A-6 Drywell Pressure Switch Found Operating Above Tech Spec Trip Setting,Initiating Drywell High Pressure Half Scram. Caused by Setpoint Drift
05000296/LER-1983-027-03, /03L-0:on 830418,offgas post-treatment Radiation Monitors (3-RM-90-265/266) Rendered Inoperable.Caused by Sample Pump Failure Due to Normal end-of-life Operation. Sample Pump Replaced
05000260/LER-1982-007-03, /03L-0:on 820126,while Performing SI 4.2.A-3, Reactor low-water Level Switch Lis-3-56A Switch Number 2 Was Found 8% Out of Tolerance.Caused by Setpoint Drift.Yarway Model 4418c Switch Recalibr & Functionally Tested
05000259/LER-1983-008-03, /03L-0:on 830210,secondary Containment Breached When Turbine Bldg to Reactor Bldg Doors Opened Simultaneously.Caused by Failure of Interlock Sys.Reactor Bldg Doors Not Closed Far Enough to Engage Strike
05000296/LER-1983-010-03, /03L-0:on 830209,main Steam Line Low Pressure Switch Found W/Low Setpoint.Caused by Instrument Drift. Switch 3-PS-1-76 Recalibr
05000296/LER-1983-009-03, /03L-0:on 830209,sample Pump Found Inoperative During Reactor & Turbine Bldg Vent Monitor CAM 3-RM-90-250 Daily Source & Background Check.Caused by Blown Fuse.Faulty Allied RS5D Relay Caused Control Room Alarm Malfunction
05000296/LER-1983-011-03, /03L-0:on 830211,during Monthly Lubrication Insps, Leak Discovered on 480-volt Reactor motor-operated Valve Board motor-generated Set 3EN.Caused by Damage During Installation of Seal Rings.Seal Rings Replaced
05000296/LER-1982-055-03, Pressure Switch PS-3-204D Found W/Setpoint of 1,125.9 Psig.Caused by Calibr Drift. Static O-ring Model 9N-AA45-X9-TT Pressure Switch Recalibr
05000296/LER-1983-001-03, /03L-0:on 830107,during Surveillance Testing Drywell Containment Spray Isolation Valve 3-FCV-74-74 Failed to Operate.Caused by Fractured Worm Shaft Clutch Gear Due to Impact Load.New Clutch Gear Installed
05000296/LER-1982-066-03, /03L-0:on 821221,discovered Mar 1982 Charcoal Sample from Control Room Emergency Ventilation Sys Had Low Methyl Iodine Removal Efficiency.Cause Unknown.Proper Tray Filter Replacement Not Performed Due to Personnel Error
05000296/LER-1982-056-03, /03L-0:on 821128,particulate Channel on 3-90-256 Drywell CAM Went Downscale Due to Moisture in Sample Chamber.Caused by Accumulation of Condensation in Sample Chamber of NMC Model AM-331F CAM.O-rings Replaced
05000296/LER-1982-054-03, /03L-0:on 821110 low-pressure Main Steamline Pressure Switch 3-PS-1-76 Had Setpoint Less than Tech Spec Requirements.Caused by Setpoint Drift.Switch Recalibr & Returned to Svc
05000260/LER-1982-036-03, /03L-0:on 821113,during Refueling Outage,Reactor Bldg Continuous Air Monitor 2-90-250 Became Inoperable Due to Broken Drive Belt on Sample Pump.Caused by Normal Wear. Std v-belt for Switzer Model 325 Svc Air Pump Replaced
05000259/LER-1982-092-03, /03L-0:on 821116,reactor Pressure Switches PS-68-93 & PS-68-64 Found Operating Below Tech Spec Requirements.Caused by Calibr Drift.Switches Recalibr & Returned to Svc
05000259/LER-1982-091-03, /03L-0:on 821109,during Diesel Generator Monthly Test,Control Room Operator Unable to Raise Speed of Diesel Generator D.Caused by Failed Woodward Governor Co Microswitch.Switch Replaced
05000296/LER-1982-051-03, /03L-0:on 821021,during Normal Operation,Drywell CAM 3-90-256 Removed from Svc for Maint Due to Erratic Flow. Caused by Vibration.Packing on Flow Control Valve NMC Model AM-331 Bf Continuous Air Monitor Tightened
05000296/LER-1983-023-03, /03L-0:on 830330,during Normal Operation,While Performing Surveillance Instruction SI 4.2.B-69,pressure Switch PS-3-204C Had as-found Setpoint of 1123 Psig.Caused by Instrument Drift.Switch Recalibr
05000259/LER-1983-017-03, /03L-0:on 830322,diesel Generator 1D Declared Inoperable When Lube Oil Circulating Pump Motor Tripped Off. Trip Caused by 480-volt Motor Leads Shorting Out,Due to Breakdown of Insulating Tape.Wiring Replaced
05000296/LER-1983-022-03, /03L-0:on 830321,during Routine Testing,Primary Containment Isolation Valve 3-FCV-77-2A Failed to Close. Caused by Oil Accumulation on Solenoid Valve Shaft, Preventing Air leak-off.Replacement Planned W/New Design
05000296/LER-1982-040-03, /03L-0:on 820818,while Performing Daily Source & Background Check of Reactor & Turbine Bldg Monitor,Inlet Sample Line Discovered Disconnected.Caused by Personnel Error.Sample Line Reconnected
05000260/LER-1982-006-03, /03L-0:on 820125,while Performing SI 4.1.A-7,low Water Level Switch LIS-3-203B,switch 1 Found 3% Out of Tolerance.Caused by Setpoint Drift.Switch Recalibr
05000296/LER-1983-012-03, /03L-0:on 830217,drywell Pressure Switch 3-PS-64-58C Operated Above Tech Spec Limit.Caused by Calibr Drift.Switch Recalibr
05000296/LER-1981-067-03, /03L-0:on 811116,continuous Air Monitor 3-RM-90-249 Failed to Sample Turbine Room Roof Exhaust W/ Fans in Operation.Caused by Worn Std V-belt for Schwitzer Model 325 Vacuum Pump.Belt Replaced & Monitor Tested
05000260/LER-1983-003-03, /03L-0:on 830213,during Refueling,Continuous Air Monitor 2-RM-90-250 Rendered Inoperable Due to Broken Drive Belt.Caused by Normal Wear Due to Continuous Operation.Std V-belt for Schwitzer Model 325 Air Pump Replaced
05000296/LER-1982-050-03, /03L-0:on 821022,during S.I.4.4.A.1,standby Liquid Control Sys Test,Valve 3-63-518 Discovered Inoperable.Caused by Separation of Plug from Globe Valve Due to Severe Throttling Svc.Plug Replaced
05000296/LER-1982-049-03, /03L-0:on 821018,reactor Low Water Level Switch LIS-3-203D Failed to Trip Below Tech Spec Level.Caused by CAM Switch Rubbing Actuator Arm.Barton Model 288 Switch Repaired & Returned to Svc
05000260/LER-1982-032-03, /03L-0:on 821006,MSIVs 1-14,1-15,1-26,1-27,1-37, 1-38 & 1-52 Exceeded Allowable Leak Rate of 11.5 Std Cubic Ft Per Hour.Caused by Atwood-Morrill Globe Valves Leaking Past Main Seat.Valves Will Be Repaired
05000260/LER-1982-030-03, /03L-0:on 821006,small Pinhole Leak Discovered in 3-inch Fire Protection Line Which Supplies Water to Cable Tray Fixed Water Spray Sys.Caused by through-wall Pitting Corrosion attack.Through-wall Hole Welded & Tested
05000259/LER-1982-077-03, /03L-0:on 820918,control Rod 38-39 Declared Inoperable Due to Fuse Failure Alarms & high-water Level Alarms Indicating.Caused by Control Rod Drive Hydraulic Control Unit Accumulator Level Switch Being Grounded
05000259/LER-1982-076-03, /03L-0:on 820925,turbine Bldg Roof Vent Monitor CAM 1-90-251 Became Inoperable.Caused by Failure of Pump Drive Motor,Model 6K562C Due to End of Natural Life.Drive Motor Replaced
05000260/LER-1982-029-03, /03L-0:on 820921,pinhole Leak Discovered in 3-inch Fire Protection Line Supplying Water to cable-tray Fixed Water Spray Sys.Caused by through-wall Pitting Corrosion Attack.Ultrasonic Testing to Be Done by 830201
05000296/LER-1982-042-03, /03L-0:on 820831,diesel Generator 3C Right Bank Air Starters Failed to Develop Min Rpm.Caused by Loose Bolts on Right Bank Air Start Valve 853-3.Bolts Tightened
05000259/LER-1982-065-03, /03L-0:on 820827,during Normal Operation While Performing Liquid Effluents Release Procedure,Discharge Isolation Setpoint Not Set as Required.Caused by Inadequate Instructions for Setpoint Verification
05000296/LER-1982-061-03, /03L-0:on 821203,drywell Atmosphere CAM RM 3-90-256 Inoperable Due to Moisture Damaged Particulate Detector.Caused by Accumulation of Condensation in Sample Chamber of CAM Due to Leakage Past O-rings
05000259/LER-1982-097-03, /03L-0:on 821203,review Revealed Several Isolation Valves Tested Less Frequently than Required by Tech Spec.Caused by Misinterpretation of NRC Guidelines When Implementing Asme,Section Xi.Instructions Revised
05000259/LER-1978-033-03, /03L-0 on 781025:radwater Airborne Effluent Monitor Recorder RM-90-252 Failed to Oper Resulting in Loss of Continuous Effluent Monitoring.Caused by Broken Input Signal Lead
05000259/LER-1978-031-03, /03L-0 on 781016:two Zones of Fire Protec Fixed Spray Piping in Reactor Bldg Were Found Transposed Due to Misinterpretation of Drawings Causing Incorrect Installation of Piping.Piping Has Been Reconnected to Agree W/Drawings
05000259/LER-1978-030-03, /03L-0:on 781013,four Heat Detectors Found to Be Connected to Incorrect Spray Zones.Elec Panel 1-25-281A Was Wired Incorrectly Causing Improper Sequencing.Detectors Were Rewired & Returned to Oper Per Tech Specs
05000259/LER-1982-095-03, /03L-0:on 821201,while Performing Diesel Generator B Redundant Start Tests,Faulty Relay Found.Caused by Burned Contact Due to Normal Wear While Stuck in Closed Position. Relay Replaced
05000259/LER-1982-072-03, /03L-0:on 820908,during Startup,Rod Worth Minimizer (RWM) Applied Rod Blocks When Rod 30-51 Selected. Caused by Listing Two Rods Twice in RWM Sequence Due to Typing Error.Rwm Sequence Corrected & Returned to Svc
05000259/LER-1982-070-03, /03L-0:on 820908,while Calibr Reactor Protection Sys high-water Level Switches on Scram Discharge Tank,Level Switch LS-85-45E Operated at 27 Gallons,Contrary to Tech Specs.Caused by Calibr Drift on Level Switch SL-305-EI-X
05000259/LER-1982-058-03, /03L-0:on 820810,elevation 620 MSL Wind Direction Recorder (1-XR-90-102-2) Read Downscale.Caused by Lightning Striking Near Environ Tower.Blown Fuses Replaced
05000259/LER-1982-055-03, /03L-0:on 820807,environ Data Station Delta Air Temp for 620-737 MSL (TDR-90-103) & 620-887 MSL (TDR-90-140) Observed to Read Downscale.Caused by Hewlett Packard Model 3450 Digital Voltmeter Failing on Ohms Range
05000260/LER-1982-024-03, /03L-0:on 820730,computer Heat Balance Calculated Reactor Thermal Power Nonconservatively Due to Erroneous Feedwater Flow Signal During steady-state Operation at 63% Power.Caused by Leaking Instrument Sensing Line Root Valve
05000259/LER-1982-050-03, /03L-0:on 820727,while Performing SI 4.9.A.4.c, Dergraded Voltage Relays on 4-KV Shutdown Boards A,B & C Operated Above Allowable Tech Spec Setpoint.Apparently Caused by Setpoint Drift Due to Increased Room Temp
05000259/LER-1982-052-03, /03L-0:on 820729,during Normal Operation,While Conducting SI 4.11.C.1,heat & Smoke Detection Operability Check,Control Power Switches for Carbon Dioxide Sys Found in Off Position.Caused by Personnel Error
05000259/LER-1982-047-03, /03L-0:on 820721,while Performing SI 4.2.A-3 (Reactor Water Level Indicating Switch) LIS-3-56D,switches 1 & 2 Operated at 454.56 Inches.Caused by Sticking Pointer on Indicator.Pointer Adjusted
05000296/LER-1982-031-03, /03L-0:on 820716,two Degraded Voltage Relay Timers on 4-kV Sdb 3EC & 3ED Found Set at 0.26-s.Caused by Timer Setpoints Change in 820329 Tech Spec Revision,But Not Incorporated Into SI 4.9.A.4.c.Timers Recalibr
05000259/LER-1982-048-03, /03L-0:on 820718,coil for Relay 16A-K37 Failed, Resulting in Partial Primary Containment Isolation.Caused by Burned Out GE Type CR 120A,Model 5000001G002 Coil.Relay Coil Replaced
05000259/LER-1982-049-03, /03L-0:on 820721 & 23,SI 4.1.A-11 (MSIV Closure Functional Test) & SI 4.5.E.1.c (HPCI Motor Operated Valve Operability Test) & SI 4.5.E.1.d & E (HPCI Flow Rate) Not Performed.Caused by Defective Procedure
05000260/LER-1982-021-03, /03L-0:on 820720,hydrogen Analyzer B Became Inoperable.Caused by Valcor Engineering Corp Solenoid Operator P/N V52630-529-1 Failure.Solenoid Replaced But Failed Again.Valve Will Be Repaired During Refueling Outage
05000260/LER-1982-025-03, /03L-0:on 820719,during Startup,Relay Coil Failed, Resulting in Partial Primary Containment Isolation.Caused by Burned Out Coil Relay,Causing Relay to Fail in Safe Direction for Primary Containment Isolation
05000260/LER-1982-022-03, /03L-0:on 820721,calculated R Factor Less than R Factor Used to Set Average Power Range Monitor Scram & Rod Block.Caused by High Core Exposure & Reduced Core Reactivity.Tech Spec Changes Issued
05000296/LER-1982-032-03, /03L-0:on 820722,two Degraded Voltage Relays on 4-kV Shutdown Boards 3EB & 3ED Found to Operate Above Max Allowable Setpoint.Setpoints Apparently Drifted Up Due to Increased Room Temp Since Last Calibr.Relays Recalibr
05000259/LER-1982-044-03, /03L-0:on 820625 & 0709,drywell Sump Pump Discharge Valve 1-FCV-77-2A Failed to Close.Caused by Failed Solenoid Valve.Valve VSG-3521 Replaced.All Versa Solenoid Valves Will Be Replaced During Future Outages
05000259/LER-1982-046-03, /03L-0:on 820701-05,intermittent Trouble Alarms Received from Fire Protection Panel 1-25-311.Caused by Common Control Card Giving Intermittent Trouble Alarms. Circuit Board Replaced
05000296/LER-1982-030-03, /03L-0:on 820713,flow Bias Compactor Trip Initiated.Flow Bias a Drifted from Accurate Value of 94% to 100% Causing high-flow Trip Points.Caused by Proportional Amplifier FQ-68-5 Drifting Upscale.Amplifier Replaced
05000259/LER-1982-043-03, /03L-0:on 820630 & 0704,delta Air Temp Recorder 620-737 MSL (TDR-90-103) Observed Reading Downscale.Caused by Blown Fuses Due to Lightning Striking in Vicinity of Environ Data Station.Fuses Replaced
05000259/LER-1982-045-03, /03L-0:on 820701,trouble Alarm Received for Control Bay Elevation 593 Fire Protection Panel 1-25-325. Caused by Failed Soldered Connections as Result of Mechanical Stresses
05000296/LER-1982-027-03, /03L-0:on 820623,hydrogen Analyzer a Inboard Sample Return Valve 3-FSV-76-57 Failed in Closed Position. Caused by V52630-529-1 Solenoid Assembly Failure Due to Damaged Lead Wire to Solenoid Operator
05000296/LER-1982-012-03, /03L-0:on 820422,drywell Pressure Switch 3-PS-64-58C,switches 1 & 2 Found Operating at 2.517 Psig, Respectively,Outside Tech Spec Limit Plus/Minus 2.5 Psig. Caused by Calibr Drift.Switch Recalibr
05000259/LER-1982-024-03, /03L-0:on 820402,low Bias Instrumentation for Average Power Range Monitor B Trip Sys Caused Automatic Rod Block & Sys to Be Nonconservative Re flow-biased Scram & Rod Block Setpoints.Caused by Failure of Transmitter
05000259/LER-1982-026-03, /03L-0:on 820422,XR-90-104 Channel C of Windspeed Indication for 887 MSL Elevation Found Inoperable.Caused by Slipping Gear in Tx Instruments Recorder,Model FS11D6D. Recorder Repaired & Returned to Svc
05000296/LER-1982-013-03, /03L-0:on 820423,while Performing SI 4.2.B-6, Pressure Switch 3-PS-64-57D Operated Above Tech Spec Limits. Caused by Setpoint drift.Static-O-Ring Switch Model 12N-AA4 Recalibr,Tested & Returned to Svc
05000296/LER-1982-014-03, /03L-0:on 820425,continuous Air Monitor 90-249 Alarmed & Insp Revealed Low Flow Alarm In.Caused by Vacuum Pump Failure Due to Normal Operation.Unit Changed Out & Returned to Svc
05000296/LER-1982-007-03, /03X-1:on 820318,ice Storm Caused Loss of Offsite Power to 4-kV bus-tie Board.Caused by Interruption of Power to Cooling Tower Transformers & 4-kV Switchgear Feeding bus-tie Board Due to Loss of 161-kV Lines
05000259/LER-1982-027-03, /03L-0:on 820425,recorders 1-RR-90-249 & O-RR-90-252 Found Out of Tolerance.Caused by Calibr Drift. Turbine Bldg Fans Stopped & Dampers Closed.Recorders Recalibr
05000260/LER-1982-014-03, /03L-0:on 820420,HPCI Sys Made Inoperable for Calibr of Speed Sensing & Control Circuits W/O Performing Surveillance Tests.Caused by Personnel Error in Failing to Determine Inoperability
05000296/LER-1982-008, Forwards LER 82-008/03L-0.Detailed Event Analysis Encl
05000296/LER-1982-015-03, /03L-0:on 820415,surveillance Functional Tests for Reactor Low Water Level SI4.1.A-7 & Pressure Suppression Chamber High Level SI4.2.B-27 Not Performed within Required 1-month Frequency.Scheduling Procedures Revised
05000259/LER-1982-016-03, /03L-0:on 820217,during Operation,Reactor Low Water Level Switch 1 (1-LIS-3-203C) Had as-found Calibr of 537.31 Inches.Caused by Instrument Drift.Switch Recalibr & Functionally Tested
05000259/LER-1982-015-03, /03L-0:on 820209,instrumentation O-XR-90-102-1, O-XR-90-102-2 (620 MSL Windspeed & Direction) & O-XR-90-103 (737 MSL Wind Direction) Failed.Caused by Lightning Striking Environ Data Station.Instrumentation Replaced
05000260/LER-1982-008-03, /03L-0:on 820127,after Calibr,Rod Block Monitor Channel B Failed to Pass Functional Test of SI 4.2.C-2. Caused by Electronic IC Failure Possibly Due to Voltage Spike During Calibr.Ge 136B1333G1 Gain Change Card Replaced
05000260/LER-1982-010-03, /03L-0:on 820121,during Full Power Operation SI 4.1.B.2 (APRM Output Signal Calibr) Not Performed within Required Frequency During 811014-28.Caused by Personnel Error
05000259/LER-1981-078-03, During Refueling Outage, Continuous Air Monitor 1-RM-90-250 Declared Inoperable for 12 1/2-h.Only Four of Seven Required Hourly Samples Taken & Sampled.Caused by Personnel Error
05000259/LER-1982-007-03, /03L-0:on 820113,XR-90-104 Lost Indication for Wind Direction & Wind Speed Channel C,Elevation 887 Msl. Caused by Anemometer & Vane Icing Due to Inclement Weather. Anemometer & Vane Allowed to Thaw
05000259/LER-1982-010-03, /03L-0:on 820112,stack Monitor Was Declared Inoperable After Low Flow Alarm.Caused by 6 Ft Segment of Sample Line Freezing,Inhibiting Sampling Flow to Monitor
05000259/LER-1982-001-03, /03L-0:on 820103,meteorological Instrumentation O-Tdr-90-103 Air Temp Delta T & O-XR-90-102-1 (30 Ft Air Speed) Failed.Caused by Lightning Damage to Transistors Q3 & Q4 & Blown Fuses in Panel 9-34 & at Meterological Station
05000259/LER-1981-094-03, /03L-0:on 811226,B Dihydrogen Dioxide Sample Return Pump Tripped & Would Not Reset.Caused by Locked Cam Bearing Due to Misalignment or Insufficient Lubrication. Cams & Cam Bearings Replaced
05000259/LER-1982-002-03, /03L-0:on 820106,drywell High Pressure Switch 1-PS-64-58C Found Isolated.Apparently Caused by Performance of Surveillance Instruction 4.2.B.5.Switch Returned to Normal & All Other Valving Involved Verified Correct
05000259/LER-1981-068-03, /03X-1:on 811106,while Transferring 1B 480-volt Shutdown Board to Normal Per Tech Specs,Normal Breaker Failed to close,de-energizing Board.Caused by Safety Pin Inserted in Push Rod.Board Breaker Replaced
05000260/LER-1981-065-03, /03L-0:on 811211,HPCI Suppression Chamber High Level Switches Discovered to Be Set 8 Inches Above Normal Level.Caused by Change to Tech Specs Not Being Reflected in Table 3.2.B.Switches Physically Lowered
05000260/LER-1981-068-03, /03L-0:on 811211,reactor Low Water Level Switch 2-LIS-3-203D Switch 1 Operated Below Limit.Caused by Switch Calibr Drift.Barton Model 288A Switch Calibr & Returned to Svc.Util Preparing Action Re Design Change
05000259/LER-1981-090-03, /03L-0:on 811215,during Normal operation,1-A Diesel Generator Right Bank air-start Motors Failed to Disengage,Rendering Generator Inoperable.Probably Caused by Malfunction of air-start Solenoid Valve
05000260/LER-1981-058-03, Dw/Torus Differential Pressure Found Less than Tech Spec Limit.No Cause Given. Alarm Setpoint at 1.26 Psi Per Design Instructions.Setpoint Raised to Alert Operator to Start Compressor Manually
05000259/LER-1981-084-03, /03L-0:on 811207,during Main Steam Line Low Pressure Calibr & Functional test,1-PS-1-72 Operated Below Tech Spec Limits.Caused by Setpoint Drift.Pressure Switch Recalibr & Design Change Request to Replace Switch Planned
05000259/LER-1981-083-03, /03L-0:on 811205,main Steam Line Radiation Monitor 1-RM-90-137 Indicated Incorrectly.Caused by Amplifier Drift. Amplifier Readjusted
05000259/LER-1981-077-03, /03L-0:on 811127,windspeed Recorder at 33 Ft Indicated Hard Upscale.Caused by Failure of Transistor Q3 on Millivolt to Current Card.Transistor Replaced,Recorder Functionally Tested & Indicator Returned to Svc
05000296/LER-1981-069-03, /03L-0:on 811118,3 EN Rmov Motor Generator Set Was Removed from Svc Due to High Vibration.Caused by Deterioration of Coupling Resulting from Loss of Lubricant. Coupling Replaced & Motor Generator Set Realigned
05000259/LER-1981-081-03, /03L-0:on 811124,1 EN Rmov Board Motor Generator Set Was Removed from Svc Due to Loss of Lubrication on Generator Coupling.Caused by Loss of Lubricant.Coupling Replaced & New Lubricant Installed
05000259/LER-1981-080-03, /03L-0:on 811124,reactor Core Isolation Cooling Sys Failed to Pass Pump Flow Rate Requirements During Operability Tests.Caused by Transmitter Amplifier Card Failure.Gemac 1589K75G702 Amplifier Card Replaced
05000259/LER-1981-074-03, /03L-0:on 811119,containment Atmosphere Dilution Tank Level Indicator a Found to Be 69% Following Calibr. Caused by Instrument Drift.Tank Filled to Greater than 74%. Recurrence Control Not Required
05000259/LER-1981-082-03, /03L-0:on 811125,reactor Core Isolation Cooling Declared Inoperable to Replace Differential Pressure Flow Transmitter.Caused by Fluid Leaking from Instrument Bellows Onto Spanning Resistors.Transmitter Replaced
05000260/LER-1981-060-03, /03L-0:on 811103,while Performing Mmi 40, Connection from Pressure Gauge to Bladder in Accumulator 24 Broke,Rendering Pump a Inoperable.Caused by Connector Being Overtightened.Bladder Replaced
05000259/LER-1981-066-03, /03L-0:on 811103,while Performing Special Instruction 4.2.B-69,recirculation Pump a Tripped.Caused by Personnel Error.Personnel Cautioned to Observe Proper Work Practices
05000260/LER-1981-061-03, /03L-0:on 811106,during Normal Operation,Nrc Inspector Observed That High Alarm on Drywell Air Sampler Was Set Above 3X Background.Setpoints Reset & Program Established to Determine Setpoint Values
05000259/LER-1981-067-03, /03L-0:on 811106,during Normal Operation,Nrc Inspector Observed High Alarm on Drywell Air Sampler Set Above 3X Background.Caused by Setpoints Not Revised Down Following Decrease in Background.Setpoints Reset
05000260/LER-1981-055-03, /03L-0:on 811020,reactor Water Level Switches LIS-3-203C & D6 Switches 1 & 2 Were Out,Of Tolerance.Caused by Setpoint Drift.Switches Recalibr.Switches to Be Replaced W/Analog Transmitters & Trip Units
05000260/LER-1981-056-03, /03L-0:on 811021,bearings on 2B Dihydrogen Dioxide Sample Return Pump Seized.Pump & Motor Replaced
05000296/LER-1981-046-03, 3 EA Rmov Board Motor Generator Set Removed from Svc.Caused by Coupling Failure Due to Loss of Lubricant.Generator to Flywheel Coupling Replaced.Couplings Inspected Weekly for Signs of Leakage
05000296/LER-1981-063-03, /03L-0:on 811023,during Normal Operation,Air Monitor 3-RM-90-256 Rendered Inoperable for Corrective Maint.Caused by Broken Drive Belt from Normal Wear Due to Continuous Operation.Belt Replaced
05000296/LER-1981-002-03, /03L-0:on 810104,excess Flow Check Valves in B3 & B7 Instrument Lines to Panel 25-7 Would Not Restrict Flow Properly.Cause Not Stated.Internals Changed & SI 4.7.D.1.d Successfully Completed
05000259/LER-1981-065-03, /03L-0:on 811027,containment Atmosphere Dilution Tank a Indicated 3% Below Operable Level.Caused by Leaky Capacitor in Power Supply That Resulted in Output Voltage Drop.Power Supply Replaced & Loop Calibr Verified
05000259/LER-1981-063-03, /03L-0:on 811025,reactor Bldg Torus Vacuum Breaker Valve Found Inoperable W/Indicator Light Out.Caused by Insulation Breakdown That Shorted Relay Coil.Coil Replaced & New Fuse Installed
05000296/LER-1981-060-03, /03L-0:on 811012,during Normal Operation,Rhr Sys II Upper Suppression Spray Isolation Valve 3-FCV-74-75 Failed to Open in Required Time Limit.Caused by Worn Lugs on Clutch.Defective Parts Replaced
05000296/LER-1981-059-03, /03L-0:on 811012,reactor Core Isolation Cooling Sys Valve 3-FCV-71-34 Failed to Close.Caused by Arcing Shield Binding Contactor.Ge 600-volt,FVR,Model IC2800 1607 Contactor Freed & Properly Aligned
05000296/LER-1981-058-03, /03L-0:on 811008,diesel Generator 3D Made Inoperable to Replace Blocking Diode in Engine Control Panel Annunication Circuit.Caused by Diode Failure Allowing Generator to Start When Alarm Reset Button Pushed
05000296/LER-1981-057-03, /03L-0:on 811007,reactor Water Level Switch LIS-3-58D Switch 1 Was Found Outside Tech Spec Limits. Caused by Setpoint Drift.Switch Insp,Calibr & Successfully Tested
05000259/LER-1981-061-03, /03L-0:on 811010,diesel Generator C Shut Down Prior to Normal Time Frame to Troubleshoot & Time ECR Relay. Cause Undetermined.Ecr Relay Calibr & Time Acceptable
05000296/LER-1981-055-03, /03L-0:on 811002,while Performing Special Instruction 4.1.A-7,LIS-3-203D Switch 1 Found Out of Tolerance by 0.31 Inches of Water.Caused by Setpoint Drift. Bellows-type Pressure Switch Recalibr
05000296/LER-1981-053-03, /03L-0:on 810929,during Normal Operation,Torus Water Level Transmitter 3-LT-64-66 Was Indicating 6.5% Lower than Allowed by Tech Specs.Caused by Instrument Drift. Transmitter Recalibr
05000296/LER-1981-054-03, /03L-0:on 810930,while Performing Special Instructions 4.2.F-10,pressure Switch PS-64-67 Found to Operate at 0.14 Psig Above Limit.Caused by Instrument Drift. Switch Recalibr & Returned to Svc
05000260/LER-1981-045-03, /03L-0:on 810916,during Scram,When Manually Initiated,Hpci Gland Seal Condenser Upper Head Gasket Began Leaking.Caused by Head Gasket Stretching Out of Place Due to Overpressurization.Gasket Replaced
05000260/LER-1981-044-03, /03L-0:on 810913,during Normal operation,hydrogen- Dioxide Analyzer B Sample Return Pump Discovered Inoperable. Caused by Failure of Pump Motor.Motor Repaired & Reinstalled
05000259/LER-1981-050-03, /03L-0:on 810903,during Operation,Interlocks for Doors 235 & 221 Failed Causing Breach of Secondary Containment.Caused by Personnel Actions Deactivating Emergency Bypass Pushbuttons
05000296/LER-1981-045-03, /03L-0:on 810831,during Startup from Hot Standby, Xenon Transient Was Experienced,Causing Frp/Cmflpd (R) Calculated to Be Less than R Setpoint.Control Rods Moved to Mitigate Effects.Observers Instructed to Set R Low
05000296/LER-1983-002-03, /03L-0:on 830112,primary Purge Sys Failed to Achieve Required Flow Rate of Greater than 10% of Design. Caused by Filter Internals Clogged W/Sand Dust from Sandblasting.New Filters Installed
05000296/LER-1982-065-03, /03L-0:on 821218,w/diesel Generator 3B Inoperable Due to Battery Testing,Control Power Off Alarm Received for Diesel Generator 3C.Diesel Generator 3C Declared Inoperable & Shutdown Initiated.Caused by Failed Coil in Relay Nv
05000296/LER-1982-063-03, /03L-0:on 821213,during Normal Operation,Turbine & Reactor Zone Exhaust Continuous Air Monitor Became Inoperable.Caused by Blown Fuse.Monitor Out of Svc for 24 H. Fuse Replaced
05000259/LER-1982-083-03, /03L-0:on 821013,sample Line Heater Discovered Unplugged,Causing Drywall Continuous Air Monitor to Fail Due to Condensation in Three Detectors.Caused by Personnel Error.Heater Plugged in
05000259/LER-1982-082-03, /03L-0:on 821011,continuous Air Monitor 1-90-256 Assumed Downscale Position Due to Miswiring of Alarm Circuit.Caused by Inadequate post-replacement Functional Test After Bell Replacement.Maint Instruction Written
05000296/LER-1982-046-03, /03L-0:on 820928,while Performing SI 4.9.A.4.b on Diesel Generator 3D,mechanical Remote Speed Control Governor Failed to Function Properly.Caused by Governor Friction Drive Plates Slipping Excessively.New Governor Installed
05000259/LER-1982-069-03, /03L-0:on 820907,during Startup Testing,Rod Sequence Control Sys Found Inoperable.Caused by Failure of GE Sequence Generator Card Model 195B948GAA.Card Replaced & Testing Satisfactorily Completed
05000296/LER-1982-038-03, /03L-0:on 820822,calculated R Factor Was Less than R Factor Used to Set Average Power Range Monitor Scram & Rod Block (1.0) for 2-h & 46 Minutes.Caused by Control Rod Pattern Adjustment in Nonequilibrium Xenon Conditions
05000259/LER-1982-063-03, /03L-0:on 820827,reactor Bldg/Turbine Air Lock Doors Opened at Same Time.Caused by Lock Being Out of Adjustment & Not Latching.Differential Air Pressure Caused Door 238 to Open When Door 237 Opened.Lock Repaired
05000259/LER-1982-061-03, /03L-0:on 820826,continuous Air Monitor 1-RM-90-250 Declared Inoperable.Caused by Broken Drive Belt Due to Normal Wear.Drive Belt Replaced
05000259/LER-1982-064-03, /03L-0:on 820823,determined Station II Cable Tray Fixed Spray Sys Did Not Meet Tech Specs.Caused by Apparent Restriction in Supply Line Strainer.Strainer Cleaned & Flushed
05000259/LER-1982-059-03, /03L-0:on 820818,during Calibr of Differential Pressure Switch That Initiates Pressure Suppression Chamber to Reactor Bldg Vacuum Breakers,Switch 1-PDIS-64-21 Operated Above Tech Specs.Caused by Calibr Drift.Switch Recalibr
05000296/LER-1982-039-03, /03L-0:on 820823,pressure Switch 3-PS-64-58C, Switch 2,found Operating Above Tech Spec Trip Level Setting. Caused by Switch Calibr Drift.Static O Ring Switch Model 12-AA4 Recalibr,Tested & Returned to Svc
05000296/LER-1983-046-03, /03L-0:on 830801,while Performing Normal Instrument Checks,Temp Indicator TI-64-55A Found Out of Tolerance.Caused by Calibr Drift.Ge Type 180 Temp Indicator Replaced & New Indicator Calibr
05000260/LER-1983-046-03, /03L-0:on 830801,HPCI Declared Inoperable.Caused by Inverter Transformer 2 Failure.Transformer Replaced & HPCI Tested Satisfactorily
05000259/LER-1983-047-03, /03L-0:on 830804,temp Switches 1-TS-69-30F & 1-TS-69-30G Operated at 157 F & 145 F,Respectively,Below Tech Spec Limit.Caused by Drift in Fenwal Type 17002-40 Temp Switch Setpoints.Switches Replaced
05000259/LER-1983-039-03, /03L-0:on 830701,during Seismic Switch Test & Calibr Procedure SI 4.2.J.2.B,switches B & C Would Not Operate Properly.Caused by Faulty Transistor & Dirty Potentiometer.Parts Replaced
05000260/LER-1983-030-03, /03L-0:on 830607,torus Exhaust Valve FCV-64-34 Bypass to Standby Gas Treatment Sys Failed to Operate within 5 Time Limit.Caused by Indicating Limit Switches Being Out of Adjustment.Switches Adjusted
05000296/LER-1983-033-03, /03L-0:on 830601,diesel Generator 3EA Lube Oil Circulating Pump Motor Tripped Off.Caused by Failure of Motor Bearings.Delco Model 12724-Y1 Motor Replaced
05000296/LER-1983-029-03, /03L-0:on 830504,during Insp of 3EA 480-volt Reactor Motor Operated Valve Board Motor Generator Set, Generator Side Flywheel Bearing Found Damaged.Caused by Mispositioning of Row Balls.Bearing Replaced
05000259/LER-1983-025-03, /03L-0:on 830502,standby Gas Treatment Sys Circuitry Switch 1-PdIS-64-15 Found Set Above Max Tech Spec Limit.Caused by Incorrect Switch Setting.Setpoint Corrected. Caution Tags Placed on Panel
05000260/LER-1983-018-03, /03L-0:on 830413,core Max Fraction of Critical Power Determined That Min Critical Power Ratio Exceeded. Caused by Withdrawal of Deep Control Rods.Control Rods Inserted to Reduce Core Max Fraction of Critical Power
05000296/LER-1981-040-03, /03L-0:on 810814,fuel Reprocessing Plant/Core Max Fraction of Limiting Power Density Calculated to Be Less than Setpoint.Caused by Xenon Transient During Cold Shutdown.Control Rods Moved
05000259/LER-1981-045, Forwards LER 81-045/03L-0.Detailed Event Analysis Encl
05000260/LER-1981-037-03, /03L-0:on 810708,value for R Factor Found Out of Limits.Caused by Extenuating Circumstances Delaying Actions Necessary to Maintain Compliance W/Limit.Personnel Briefed on Close Monitoring of R Factor During Startup
05000260/LER-1981-041-03, /03L-0:on 810709,unit Crossconnect Capability Between Units 2 & 3 Reduced to One RHR Pump When RHR Pump 3C Became Inoperable.Caused by Pump Motor Failure on Ground Overcurrent During Testing
05000259/LER-1979-034-03, /03L-0:on 791126,while Conducting Relay Testing on Unit 3 Recirculation Pump Boards,Relays Inadvertently Tested on Unit 1 Pump Board,Shutting Down Both Recirculation Motor Generator Sets.Caused by Personnel Error
05000259/LER-1981-022-03, /03L-0:on 810507,during Refueling,Relay 14A-K19B Found to Exceed Tech Spec Table 3.2.B Requirement for Operation of 6 to 8-s.Caused by Time Delay Relay Out of Calibr.Time Delay Relay Adjusted
05000296/LER-1981-023-03, /03L-0:on 810510,during Redundant Start Test,Left Bank Starters Would Not Develop Min Rotational Speed.Caused by Sticking Vanes Due to Dirty motor.Ingersoll-Rand Air Start Motors Replaced
05000296/LER-1981-019-03, During Shutdown,When HPCI Sys Initiated,Upper & Lower HPCI Gland Seal Condenser Head Gaskets Were Blown.Caused by Overpressurization of Tube Side of HPCI Gland Seal Condenser.Gaskets Replaced
05000296/LER-1981-022-03, /03L-0:on 810511,during Normal Operation,Valve FCV-74-57 Motor Starter Thermal Tripped Upon Opening & Closing.Caused by Broken Bolts Which Hold Motor Together. Motor Bolts & Bearings Replaced
05000259/LER-1981-021-33, /033-0:on 810505,continuous Air Monitor for Reactor/Turbine Bldg Ventilation Declared Inoperable.Caused by Failure of Model SC-2-15 Iodine Detector.Continuous Air Monitor Repaired & Tested
05000259/LER-1981-015-03, /03L-0:on 810428,during Refueling Outage,Air Monitor 1-RM-90-250 for Reactor Turbine Bldg Ventilation Found Inoperable Due to Instrument Indicating Downscale. Caused by Failed Detector High Voltage.Voltage Repaired
05000259/LER-1981-017-03, /03L-0:on 810423,Athens 161Kv Line & D Cooling Tower Switch Gear Tripped.Diesel Generators Failed to Immediately Demonstrate Operability Per Tech Spec 4.9.B.1. Caused by Personnel Error.Operators Will Review Incident
05000260/LER-1981-005-03, /03L-0:on 810119,core Max Fraction of Limiting Power Density Exceeded Limit for One Node in Core.Caused by Operation Close to Limit in Conjunction W/Minor (Normal) Perturbation in Monitored Parameters.Power Reduced Slightly
05000260/LER-1981-003-03, /03L-0:on 810112,core Spray Pump Discharge Pressure Switch 2-PS-75-16 Found Outside Tech Spec Limits. Caused by Setpoint Drift.Switch Recalibr & Replaced
05000296/LER-1981-001-03, /03L-0:on 810106,both Smoke Detectors in Reactor Bldg Fixed Spray Zone Were Inoperable.Caused by Loose Screw in Terminal Block.Screw Replaced
05000296/LER-1981-003-03, /03L-0:on 810107,during Refueling Outage,Fuel Pool Cooling Sys Auto Isolated When Power Was Removed.Fuel Pool Sampling Not Performed on 8-h Schedule.Caused by Personnel Error.Personnel Reinstructed
05000259/LER-1980-088-03, /03L-0:on 801202,diesel Generator 1c Tie Breaker 1812 on 4-kV Shutdown Board C Tripped.Caused by Faulty Diode in Overspeed Trip Annunciator Relay Circuit Permitting Spurious Signal to Operate Overspeed Trip Relay
05000259/LER-1981-007-03, /03L-0:on 810210,during Fire Door Insp,Fire Door Damper (Door 472) Not Closed.Caused by Paint Buildup in Operating Mechanism.Damper Closed & Other Dampers Inspected. Procedure for Insp & Preventive Maint Will Be Written
05000259/LER-1981-018-03, /03L-0:on 810504,during Refueling,While Performing Automatic Depressurization Sys Timer Calibr,Relay 2E-K35 Was Operating in 126,exceeding Tech Spec Limits.Caused by Normal Aging & Use.Relay Was Recalibr
05000260/LER-1981-007-03, /03L-0:on 810129,during Power Increases,Tech Spec Limit of 13.33 Kw/Ft for Linear Heat Generation Rate Exceeded in One Node.Node Reached 13.77 Kw/Ft.Caused by Xenon Transient Resulting from Increased Core Power
05000260/LER-1980-056-03, /03L-0:on 801215,reactor Water Level Switch LIS-3-56A Switch 2 Setpoint Found Outside of Tech Spec Limits.Caused by Yarway Model 4418c Setpoint Drift.Switch Recalibr & Functionally Tested for Repeatability
05000296/LER-1981-024-03, /03L-0:on 810514,HPCI Turbine Tripped on Overshoot During Fast Start Test.Caused by Loose Cable Connector at Egr Actuator Preventing Proper Egr Operation.Connectors Tightened
05000259/LER-1981-011-03, /03L-0:on 810421,local Fire Protection Panel Circuit Breaker 25-331 Tripped & de-energized Panel.Cause Unknown.Breaker Reset
05000260/LER-1981-018-03, /03L-0:on 810418,xenon Transient Observed Following Control Rod Sequence Exchange.Caused by Earlier Load Reduction in Conjunction W/New Control Rod Pattern. Control Rods Inserted & R Factor Brought within Limits
05000259/LER-1981-028-03, /03L-0:on 810531,standby Gas Treatment Train C Relative Humidity Control Heater Circuit Breaker Found Tripped During Testing.Caused by Mechanical Failure.Circuit Breaker Replaced
05000260/LER-1981-011-03, /03L-0:on 810311,during Normal Operation,Core Spray Sys I Flow Indicator 2-FI-75-21 Failed to Indicate Flow.Caused by Failure of Transmitter Model 555111BDA3AAA. Transmitter Replaced & Required Testing Performed
05000296/LER-1980-045-03, /03L-0:on 801105,during Normal Operation,While Performing SI 4.2.A.6,setpoint for 3-PS-1-76 Found Below Tech Spec Limits.Caused by Model B2TA12SS Switch Setpoint Drift.Switch Recalibr,Verified & SI 4.2.A.6 Completed
05000296/LER-1980-055-03, /03L-0:on 801210,continuous Air Monitor 3-RM-90-250 Declared Inoperable.Caused by Electronic Window Card Malfunction in Model AM-331F(BF).Card Repaired
05000296/LER-1980-050-03, /03L-0:on 801115,breaker for Standby Liquid Control Pump B Motor Tripped When Pump Started.Caused by Overcurrent Tripping Device on B Phase Tripping at Lower Value than Other Phases.Breaker Replaced
05000296/LER-1980-049-03, /03L-0:on 801114,RHR Pump 3D Tripped on Instantaneous Overcurrent While Starting.Caused by Loose Relay Adjustment Locknut.Locknut Tightened & Relay Adjusted
05000259/LER-1980-084-03, /03L-0:on 801112,alternate Feeder Breaker 1930 Failed to Close.Caused by Lack of Contact Between Fuse Clip & Breaker Fuse & Dirty Auxiliary Contacts.Fuse Clip Adjusted & Contacts Cleaned
05000296/LER-1980-047-03, /03L-0:on 801108,during Normal Operation, Difficulties Encountered While Trying to Determine EECW Flow to 3B & D Core Spray Room Cooler.Caused by Biofouling,Silt Accumulation & Corrosion
05000296/LER-1980-043-03, /03L-0:on 801019,flow Bias Circuitry of Average Power Range Monitor High Flux Drifted High & Declared Inoperative.Caused by Water from Removal of RHR Heat Exchanger Head Draining on Panel 25-7,shorting Out Leads
05000259/LER-1980-079-03, /03L-0:on 801025,electrical Ground Occurred at HPCI Egr Actuator,Causing Failure of Egm Output Transistors Q9 & Q10.Caused by Corrosion Between Egr Actuator Connector & Connector Pins.Actuator & Box Replaced
05000296/LER-1981-017-03, /03L-0:on 810408,reactor Water Level Switch 3-LI-3-46B Was Removed from Panel 9-5 & Taken to Instrument Shop for Repair.Caused by Indicator Movement Sticking Due to Faulty Bearing.Indicator Repaired,Tested & Returned to Svc
05000296/LER-1981-004-03, Diesel Generator 3A & Breaker 1836 Tripped from Generator Overspeed During Testing.Caused by Vs Relay on Speed Sensing Panel Energizing at Less than 870 Rpm,Closing Breaker 1836
05000260/LER-1981-009-03, /03L-0:on 810302,recirculation Motor Generator Sets 2B & 2A Tripped.Caused by Resistance Temp Detector Operating 2A-K45B Relay & Tripping 2B Set.Set 2A PT Fuse Compartment Door Jarred & Circuit Interrupted
05000296/LER-1980-056-03, /03L-0:on 801215,during Refueling,Diesel Generator Voltage Available Relay Found Dropped Out.Caused by Open Wire in Cable.Cable Replaced
05000260/LER-1981-013-03, /03L-0:on 810111,surveillance Test on Jet Pumps SI 4.6.E.1,was Inadvertently Omitted.Caused by Personnel Error.Employee Who Handles Tracking Sys Has Been Cautioned Re Necessity to Perform SI as Scheduled
05000296/LER-1981-009-03, /03L-0:on 810203,diesel Generator 3C Failed to Stop within Appropriate Time.Diesel Shut Down & on Attempted Restart Failed Two Out of Three Times.Failure to Stop Caused by Relay Failure.Cause of Inoperability Unknown
05000296/LER-1981-008-03, /03L-0:on 810202,RHR Pump Found Inoperable.Caused by Loose Pump 3D Breaker Trip Adjustment Nut & Adjustment Change,Causing Breaker to Trip Free on Attempting to Close. Breaker Replaced.Adjustment Locknut Tightness Checks Add
05000296/LER-1980-061-03, /03L-0:on 801230,SLC Pump Discharge Relief Valve 3B Would Not Relieve within Tech Spec.Caused by Galled Valve Disc or Disc Binding W/Valve Guide.Valve Replaced
05000259/LER-1980-092-03, /03L-0:on 801230,standby Gas Treatment Train C Relative Humidity Heaters Did Not Function Properly.Caused by Open TE-65-60B Switch.Switch Repaired
05000260/LER-1980-059-03, /03L-0:on 801230,FR-77-16 Observed Downscale During Drywell Equipment Drain Sump Pump Operation.Caused by Shift in Model 555 GE Transmitter FT77-16 Zero Adjustment. Transmitter Recalibr,Tested & Returned to Svc
05000296/LER-1980-060-03, /03L-0:on 801231,seventeen Scram Accumulator Level Switches Found Inoperable.Caused by Dirty Floats. Switches Cleaned;One Replaced
05000259/LER-1980-075-03, /03L-0:on 801006,valve Position Indication for Steam Supply valve,FCV-71-3,lost.Caused by Corrosion on Terminal Block Inside Junction Box.Corroded Terminals Bypassed Temporarily & Will Later Be Replaced
05000296/LER-1981-011-03, /03L-0:on 810224,coupling Damage Was Found on 3DA Rmov Bd MG Set.Caused by Misalignment & Loss of Lubricant.Coupling Seal Found Separated.Mg Set Realigned, Coupling Replaced & All Other Set Couplings Repaired
05000259/LER-1980-066-03, /03L-0:on 800902,during Normal Operations, Annunciation on Torus Hydrogen Containment Atmosphere Monitor Was Observed.Caused by Failure of Model 3.5 SS Relay in Safe Direction.Monitor Repaired & Returned to Svc
05000296/LER-1980-037-03, /03L-0:on 800909,during Normal Operation,While Surveillance Testing,Hydrogen Analyzing Sys H2M-76-39 Would Not Calibr to Specs.Caused by Instrument Failure.Hydrogen Analyzing Sys Will Be Changed to Newly Designed Sys
05000259/LER-1980-063-03, /03L-0:on 800820,during Normal operation,CAM-1-RH- 90-251 for Turbine Bldg Roof Vent Removed from Svc for Period Exceeding 1-h Due to Failure of Schwitzer Series 325 Model 145473 Vacuum Pump.Pump Replaced
05000259/LER-1980-064-03, /03L-0:on 800820,during Normal operation,CAM-1- RM-90-249 for Turbine Bldg Roof Vents Removed from Svc for Period Exceeding 1-h.Caused by Personnel Error.Personnel Cautioned to Observe Time Limit
05000296/LER-1980-029-03, /03L-0:on 800802,Surveillance Procedure 2.1 Performed W/Computer Valve Improperly Set Resulting in Use of Previous Day Values for Max Average Planar Linear Heat Generation Rate.Caused by Personnel Error
05000259/LER-1980-055-03, /03L-0:on 800708,during HPCI Special Instruction 4.5.E.1.d & E,Pdv 73-43 Failed to Operate Properly.Caused by Valve Stuck Closed Due to Loose Valve Guide.Valve Disassembled & Cleaned & Valve Guide Tightened
05000259/LER-1980-043-03, /03L-0:on 800411,during Test Instruction 36A, W/Unit at 85% power,1A RHR Heat Exchanger Was Found Leaking. Caused by Six Loosened Lock Nuts.Gasket Replaced & Tested Per Mechanical Maint Instruction 49
05000259/LER-1980-029-03, /03L-0:on 800407,HPCI Turbine Tripped Due to Failed Rupture Disc in Turbine Exhaust Line.Teflon Sheet Failed Providing No Protection to Rupture Disc.Cause of Teflon Sheet Failure Unknown.Disc Replaced
05000259/LER-1980-050-03, /03L-0:on 800624,during Performance Check,Found Pressure Switch PS-47-144 Miswired.Caused by Personnel Failure to Follow Proper Procedures for Working on Cssc Equipment.Pressure Switch Rewired Correctly
05000259/LER-1980-045-03, /03L-0:on 800602,at 80% Power,Hpci Failed to Meet Flow Requirements Because Turbine Stop Valve Tripped.Caused by Worn Mechanical Overspeed Trip Piston.New Parts Installed & Tested
05000259/LER-1980-040-03, /03L-0:on 800506,during Routine Startup,Valve 1-FCV-90-257-A Would Not Fully Open After Closing.Caused by Short Circuit Due to Failure of Micro Switches in Valve Actuator.Switches Failed Due to Condensation in Actuator
05000259/LER-1980-041-03, /03L-0:on 800508,during Normal Operation,Smoke Detector in Reactor Bldg Alarmed & Would Not Clear.Caused by Increased Detector Sensitivity.Detector Replaced & Fire Watch Established Until Repairs Made
05000259/LER-1980-020-03, /03L-0:on 800301,during Normal Operation,W/High Winds & Freezing Rain,Trinity Offsite 161-kV Power Source Was Lost Intermittently.Caused by Ice Loading & High Winds Requiring Operation of Line Protective Relay
05000259/LER-1980-033-03, /03L-0:on 800417,during Normal operation,480-volt Reactor Motor Operated Valve Board 1E Tripped & Locked Out on Overcurrent.Caused by Short Circuit on Hot Side of Spare Breaker Compartment 3A.Breaker Changed
05000259/LER-1980-024-03, /03L-0:on 800312,during Refueling Outage W/Units 2 & 3 Under Normal Operation,Nut Came Off Bracket Holding Insulated Communications Ground Wire Above Athens 161-K Line,Causing Fault Resulting in Trip of Breakers
05000259/LER-1980-008-03, During Scheduled Refueling Outage,Hpci Turbine Had Crack in Coupling Bearing Support Pedestal.Possibly Caused by Water Hammer in Main Steam Supply Line
05000260/LER-1980-009-03, /03L-0:on 800213,during Normal Operation,Steam Line B Radiation Monitor 2-RM-90-138 Failed Downscale Resulting in Half Scram & Half Isolation.Caused by Loss of Power Output from Power Drawer.Power Drawer Replaced
05000260/LER-1980-010-03, /03L-0:on 800216,during Hot Shutdown,Crack Was Found in HPCI Turbine Coupling Bearing Support Pedestal. Probably Caused by Water Hammer While Warming HPCI from out- of-svc Condition.New Pedestal Installed
05000259/LER-1980-010-03, /03L-0:on 800129,during Scheduled Refueling Outage,Found That Various Instrument Sensing Line Hangers in HPCI Pump Room Were Broken.Caused by Water Hammer While Warming HPCI Sys.Hangers Repaired
05000259/LER-1980-009-03, /03L-0:on 800125,SI 4.2.A-10,reactor Bldg Monitoring Was Performed Three Weeks Late.Caused by Oversight by Cognizant Section.Personnel Instructed to Be More Aware of Due Dates
05000259/LER-1980-006-03, /03L-0:on 800122,during Refueling Operations, Control Rod Driveline Accumulator Level Switch LS-1-305-129 on Unit 38-11 Was Found Inoperable.Caused by Broken Reed Switch.Switch Replaced
05000260/LER-1983-032-03, /03L-0:on 830610,number of Offsite Power Sources Available Reduced to One When Main Transformer 2B Removed from Svc for Maint.Caused by Inadequate Brazing of Low Voltage Coil Connections.Connections Repaired
05000259/LER-1979-002-03, /03L-0 on 790129:during Normal Operation While Performing Surveillance Test,Standby Liquid Control Pump 1B Relief Valve Opened Below Tech Spec Min.Caused by Valve Seat Surface Deterioration
05000259/LER-1979-028-03, /03L-0:on 791017,flow Control Valve 73-27 Would Not Open.Caused by Dirty Contacts on Control Valve 73-27 Limitorque Operator Limit Switches.Limit Switch Contacts Cleaned
05000259/LER-1979-030-03, /03L-0:on 791023,during Surveillance Testing,Torus Hydrogen Sensor Gave High Indication for 4% Calibr Gas. Caused by Degradition of Sensor.Redundant Sensor Placed in Svc
05000259/LER-1979-021-03, /03L-0:on 790902,containment Isolation Valve FCV-71-3 Would Not Close.Caused by Failure of Peerless Electric Motor S/N GV7995.Operating Limits of Valve Reset & Tested.Motor Replaced
05000259/LER-1979-020-03, /03L-0:on 790831,containment Oxygen Concentration Exceeded 4% & drywell-suppression Chamber Differential Pressure Decreased Below 1.0 Psid During Normal Operation. Caused by Deferral of Planned Shutdown
05000296/LER-2078-001, For Browns Ferry Nuclear Plant, Unit 3, Torus Oxygen Sensor O2M-76-42 Found to Be Erratic & Did Not Meet Requirements of Technical Specification 4.7.H During Normal Operation
05000260/LER-2077-012, For Browns Ferry Nuclear Plant, Unit 2, Two Hydraulic Snubbers Were Found Inoperable During the Performance of Surveillance Instruction 4.6.H
05000296/LER-2077-016, For Browns Ferry Nuclear Plant, Unit 3, Torus Oxygen Sensor O2M-76-42 Failed to Operate Properly During Normal Operation
05000296/LER-2078-005, For Browns Ferry Nuclear Plant, Unit 3, Six CRD Accumulator Level Switches Which Would Not Alarm with Level Increases During Plant Operation While Performing Electrical Maintenance Instruction 50
05000296/LER-2078-003, For Browns Ferry Nuclear Plant, Unit 3, Valve FCV 3-74-52 Was Found Inoperable During Performance of Surveillance Instruction 4.5.B.1.C
05000260/LER-2078-002, For Browns Ferry Nuclear Plant, Unit 2, Reactor Pressure Switch PS-68-95 Not Functioning as Required by Tech Spec Table 4.2.B During Normal Operation While Performing Surveillance Instruction ST 4.2.B-7
05000260/LER-2078-001, Surveillance Samples Were Taken from Charcoal in Unit 2 Primary Containment Purge System Following Maintenance Outage
05000260/LER-2078-008, For Browns Ferry Nuclear Plant, Unit 2, Reactor Building Ventilation Radiation Monitoring Channel Failed During Refueling Outage
05000296/LER-1981-025-03, /03L-0:on 810515,HPCI Suppression Chamber High Level Switch 3-LS-73-57B Failed to Operate During Testing. Caused by Stuck Float Chamber.Switch Float Chamber Flushed & Tested
05000260/LER-1980-051-03, /03L-0:on 801121,reactor Water Level Switch 2-LIS-3-58C Switch 4 Found Inoperable at Proper Setpoint. Caused by Dirty Switch Contacts.Contacts Cleaned & Checked at Proper Setpoint
05000260/LER-1980-044-03, /03L-0:on 801012,refueling Zone Inboard Isolation Time Delay Relay R3A Found Out of Tolerance & Nonrepetitive. Caused by Relay Failure.Relay,Agastat Model 7022 Ab,Replaced & Calibr
05000260/LER-1980-054-03, /03L-0:on 801004,refuel Interlocks Switch 2 Jammed in Overtravel Position,Rendering Switch Inoperable & Allowing Movement Toward Core in Startup Mode.Caused by Switch Operating Arm Rotating 180 Degrees
05000260/LER-1980-018-03, /03L-0:on 800321,during Normal operation,2A Reactor Recirculation Motor Generator Set Tripped.Caused by Generator Stator Temp High Relay Actuation
05000296/LER-1980-009-03, /03L-0:on 800404,during Normal Operation,Relay 16A-K63B Overheated & Failed,Blowing Fuse Causing Containment Isolation Sys Group 6 Valves to Fail Closed. Caused by Natural Aging of Relay.Relay & Fuse Replaced
05000260/LER-1980-016-03, /03L-0:on 800310,after Startup,Discovered Roof Valve Failure After Being Closed During Short Outage to Allow Repair on Instrument Panel.Caused by Blocked Sensing Line & Slow Leak.Valve Mechanically Cleared
05000296/LER-1979-025-03, /03L-0:on 791212,following Return to Svc After Refueling Outage,Reactor Core Isolation Cooling Failed to Reach Rated Flow.Caused by Short in Reactor Core Isolation Cooling Egm Box.Ground Wire Causing Short Removed
05000260/LER-1980-003-03, /03L-0:on 800122,during Normal Operation,Momentary Breach of Secondary Containment Occurred When Air Lock Doors Between Turbine & Reactor Bldg Were Simultaneously Opened.Caused by Misaligned Latch Lock & Latch Bolt
05000260/LER-1979-017-03, /03L-0 on 790615:during Normal Operation,Setpoint on Pressure Switch PS-3-22D Exceeded Specified Limit.Caused by Drift in Model B2T-A12SS Switch.Switch Recalibr & Satisfactorily Tested
05000260/LER-1979-018-03, /03L-0 on 790727:indicating Lights Failed for Reactor Bldg to Torus Vacuum Breaker,Fcv 2-64-21.Valve Inoperative Contrary to Tech Specs.Caused by Control Circuit Fuse Blowing Due to Failure of Coil for Relay 16A-K40
05000260/LER-1979-007-03, /03L-0 on 790503:during Refueling Outage,Five MSIVs Exceeded Leakage Limits.Caused by Irregularities on Valve Seating Surfaces & Entrapment of Debris Under Seating Surfaces.Valves Will Be Repaired & Retested
05000296/LER-1978-028-03, /03L-0 on 781014:during Refuel outage,1 Smoke Detector XS-39-108ZE in Mech Equip Room on Elevation 617 Caused False Alarm That Would Not Clear.Caused by Normal Natural Aging of Detector
05000260/LER-1980-021-03, /03L-0:on 800506,during Routine Shutdown, Particulate Channel 2-RR-90-249 Was Erratic & Declared Inoperable.Caused by Failure of Recorder Amplifier.Amplifier Replaced.Failure Attributed to Normal Aging
05000296/LER-1979-015-03, /03L-0:on 790915,annunciator Panel XA-55-20B Became Inoperable,Making Two Fire Alarm Circuits Inoperable. Caused by Inverter Printed Circuit Card Failure Due to Natural Aging.Circuit Card Replaced
05000260/LER-1979-001-03, /03L-0 on 790113:during Test of high-pressure Injection Coolant Sys,Steam Supply Valve FCV-73-16 Failed to Open,Rendering Sys Inoperative.Caused by Failure of Limitorque Valve Operator Limit Switch
05000260/LER-1979-004-03, /03L-0 on 790414:reactor Bldg,Turbine Bldg & Refueling Zone Vent Exhaust Monitor RM-90-250 Failed Surveillance Test SI 4.8.B-4.3,Section 4e.Caused by Failure of Input Card for Radiation Monitor
05000296/LER-1979-002-03, /03L-0 on 790117:during Maintenance of Reset Switch,Short Circuit Damaged Power Supply & Sensor Circuit Board,Rendering Fixed Spray Automatic Initiation Circuit for Fire Protection Inoperable
05000296/LER-1979-009-03, /03L-0 on 790717:hydrogen Ignition Damaged HEPA Filters.Caused by Improper Offgas Recombiner Preheater Operation.Sys HEPA Filters & Charcoal Bed Inspected.Three Filters Replaced.Procedures Will Be Revised
05000260/LER-1978-018-03, /03L-0 on 781103:reactor Pressure Switch PS-6B-96, Switch 1 Failed to Operate During Surveillance Testing. Switch Exercised & Adjusted
TMI-22-017, 2021 Annual Radiological Environmental Operating Report
05000259/LER-1978-032-03, /03L-0 on 781022:offgas Sampling Pump a Malfunctioned & Pump B Motor Would Not Start.Caused by Vanes Sticking on Pump A,Model MB21 Mfg by Metal Bellows Corp. Bearings & Centrifugal Switch Failed on Pump B Motor
05000259/LER-1981-064-03, /03L-0:on 811027,switch 1 of Recirculation Discharge Valve Closure & Switch 2 of Cs/Rhr Valve Opening Permissive Were Outside Tech Spec Limits.Caused by Setpoint Drift.Switches Reset.Design Change Request Initiated
05000296/LER-1980-046-03, /03L-0:on 801030,during Steady State Operation W/Unit at 92% Power,Damaged Standby Liquid Control Hydraulic Accumulator Air Valve Resulted in Loss of Charge While Performing MMI-40.Caused by Worker Tightening Valve
TMI-21-019, Submittal of 2020 Annual Radiological Environmental Operating Report
05000296/LER-1981-070-03, /03L-0:on 811211,during Normal Operation, HPCI Suppression Chamber High Level Switches Found 8 Inches Above Normal.Caused by Tech Spec Change Revising Normal Water Levels.Level Switches 73-57A & B Lowered
05000296/LER-1983-038-03, /03L-0:on 830624,while Performing SI 4.2.F-6 (Suppression Chamber Water temp),TI-64-55A Temp Indicator Found Out of Tolerance.Cause Not Stated.Failure Determined to Be Random Occurrence
05000260/LER-1983-058-03, /03L-0:on 830927,operator Observed Diesel Generator 1C Trouble Alarm.Caused by Failed Control Power Transformer for Immersion Water Heaters & Lube Oil Circulating Pump.Transformer Replaced
05000260/LER-1983-056-03, /03L-0:on 830920,while Performing SI 4.2.B-57, Discovered That RHR Pump 2C Cooler Fan Would Not Operate. Caused by GE CR124CO28 Overload Relay Tripping.Overload Relay Replaced
05000296/LER-1983-007-03, /03L-0:on 830128,during Monthly Vibration Checks, Generator/Flywheel Ball Bearing Developed High Vibration Levels.Cause Suspected to Be Normal Wear.Bearing Replaced
05000296/LER-1983-006-03, /03L-0:on 830128,during Shutdown,While Performing Monthly Vibration Tests on 480-volt Reactor Motor Operated Valve Motor Generator Sets,High Vibration Readings Detected. Caused by Leak in Seal Ring.Coupling & Rings Replaced
05000259/LER-1983-038-03, /03L-0:on 830627,trouble Alarm Came in for Control Bay Elevation 593 Fire Protection Panel 1-25-325,Zone 14,due to Power Loss to Some Smoke Detectors.Power Loss Caused by Loose Wire Connected to Detector XS-39-104BE
05000259/LER-1983-026-03, /03L-0:on 830525,containment Atmosphere Dilution Tank B Level Transmitter LT-84-13A Indicated Above Tech Spec Limit.Caused by Transmitter Zero Drift.Transmitter Recalibr
05000259/LER-1983-010-03, /03L-0:on 830224,while Performing SI 4.7.B-3, Standby Gas Treatment Train B Declared Inoperable Due to Failure to Meet Flow Distribution Requirements.Caused by Debris in HEPA Filters.Filters Replaced
05000260/LER-1983-028-03, /03L-0:on 830526,during Normal Operation,Hpci Sys Declared Inoperable Due to Blown Inverter Fuse.Fuse Replaced.Hpci Turbine Control Valve Failed to Open Due to Misadjusted Rod.Rod Adjusted
05000259/LER-1983-027-03, /03L-0:on 830526,discovered That Surveillance Instruction 4.8.3.4-3 for Reactor Bldg Vent Monitoring Sys Calibr Not Performed within Required Interval.Caused by Personnel Error.Calibr Performed
05000296/LER-1983-028-03, /03L-0:on 830429,while Investigating Blown Fuse in Annunication,Relay 16A-K79 Failed.Caused by Coil Over Heating Melting Spool Matl & Stuck Armature in Energized Position.Relay Replaced
05000296/LER-1982-002-03, /03L-0:on 820121,during Surveillance Test SI 4.11.C.1 & 5 Smoke Detector in Auxiliary Instrument Room 3 Would Not Alarm.Caused by Loose Annunciator Point Card Due to Incorrect Installation of Retainer Bar
05000259/LER-1982-011-03, /03L-0:on 820124,continuous Air Monitor O-RM-90-252 Found Out of Calibr.Caused by Component Failure. NMC Count Rate Card Number CRA14-A & Triplett Number 420-G Iodine Meter on Continuous Air Monitor Replaced
05000260/LER-1983-021-03, /03L-0:on 830423,calculated R Factor Less than Flow Bias Tech Spec Setpoint.Caused by Pulling Group of Eight Rods Four Notches to Fully Withdrawn Position.Tech Spec Revs Submitted
05000259/LER-1982-089-03, /03L-0:on 821103,during Primary Containment Purge Sys Filter Pressure Drop Test,Primary Purge Sys Failed to Achieve Required Flow Rate.Caused by Clogged HEPA Filters. New Filters Installed & Satisfactorily Tested
05000260/LER-1983-012-03, /03L-0:on 830323,during Startup Testing at 50.4% Power,Discovered Process Computer Contained Nonconservative Kf Factor.Caused by Increased Recirculation Stops at End of Previous Cycle for Increased Flow Operation
05000296/LER-1983-025-03, /03L-0:on 830419,during Normal Operation,Drywell Temp Indicators IS-64-67,TI-64-52A & TM-64-52 Drifted Out of Tolerance & Beyond Tech Spec Limit.Instruments Recalibr & Functional Tested
05000260/LER-1983-010-03, /03L-0:on 830322,CRD 10-39 Failed to Scram While Performing SI 4.3.C.Caused by Valve Stem Separating from Valve Seat in Valve 85-617
05000259/LER-1983-022-03, /03L-0:on 830429,downstream HEPA Filters in Standby Gas Treatment Sys Trains a & B Exceeded Tech Spec 18-month Test Frequency.Caused by Personnel Error.Procedure SI 4.7.B-4 Review Rescheduled
05000259/LER-1982-084-03, /03L-0:on 821018,reactor Water Level Switches 1 & 2 of LIS-3-203B as-found Calibr Violated Tech Specs. Caused by Instrument Drift.Switches Recalibr,Functionally Tested & Returned to Svc
05000296/LER-1983-013-03, /03L-0:on 830217,while Performing ST 4.2.F.7, Suppression Pool Level Instrument Loop 64-66 Found Out of Tolerance.Caused by Setpoint Drift of Level Transmitter & Level Indicator.Transmitter Recalibr & Tested
05000259/LER-1982-090-03, /03L-0:on 821104,secondary Containment Breached When Turbine to Reactor Bldg Doors Opened Simultaneously During Door Interlock Maint.Caused by Insufficient Control While Interlocks Inoperable.Door Watch Instructions Written
05000259/LER-1983-072-03, /03L-0:on 831227,mean Sea Level Wind Speed Recorder XR-90-104 Read Zero.Caused by Ice Formation on Wind Speed Sensor
05000260/LER-1983-020-03, /03L-0:on 830410,during Power Maneuvers for Recirculation Sys Testing,Calculated R Factor Was Less than R Setpoint for 2 H 45 Minutes.Caused by Power Peaking Due to Xenon Transients from Previous Power Changes
05000260/LER-1981-026-03, /03L-0:on 810520,inservice Insp Ultrasonic Exam Did Not Receive Required Evaluation.Caused by Effect of Reduced Recording Level Not Being Recognized Until Recent Questions Were Raised in Area.Procedures Clarified
05000259/LER-1982-073-03, /03L-0:on 820910,while Performing Maint on Diesel Generator A,Fuel Oil Flowed Out Discharge Filter Drain Valve When Transfer Pumps Supplied Oil to Day Tank.Caused by Personnel Error.Responsible Person Reinstructed
05000259/LER-1980-087-03, /03L-0:on 801201,while Performing SI 4.2.B.24,core Spray Sparger to RPV Differential Pressure Switch PDIS-75-28 Found to Operate Out of Tech Specs Limits.Caused by Instrument Drift.Switch Inspected & Recalibr
05000260/LER-1981-010-03, /03L-0:on 810306,during Normal Operation,Special Instruction 4.1.B.2 Was Not Performed.Caused by Personnel Error.Personnel Cautioned to Perform Instructions as Scheduled