05000412/LER-1989-019, :on 890622,plant Shut Down Due to Tube Leak in Steam Generator C.Caused by Operating Shift Performing Numerous Concurrent Tasks While Controlling Steam Generator Levels.Event Reviewed W/All Licensed Operators
05000298/LER-1989-008, :Insufficient Operator Guidance to Assure Adequate Svc Water Flow During Design Basis LOCA Identified During NRC Insp on 870511-0619.Caused by Procedural Deficiency.Procedures Revised
05000412/LER-1989-015, :on 890514,steam Driven Auxiliary Feedwater Pump Shutdown Due to Speed Oscillations Caused by Hydraulic Governor Hunting.Caused by Inadequate Preplanning. Surveillance Tests Revised
05000412/LER-1987-016, :on 870816,motor Driven Auxiliary Feedwater Pump 2FWE-P22 Started Inadvertently.Caused by Isolation of Pressure Switch 2FWE-PS158B,which Provided Erroneous Low Signal.Ltr Issued Detailing Lessons Learned
05000245/LER-1987-033, :on 870812,LPCI Subsystem a Inadvertently Initiated.Caused by Technician Error When Test Plug Connected to Wrong Jack During Surveillance on Automatic Pressure Relief Sys.Procedure Reviewed
05000327/LER-1987-044, :on 870724,determined That Moderate Energy Line Breaks Might Impair Components Required for Safe Shutdown. Caused by Inadequate Analysis of Breaks Due to Inadequate Communication.Bldg Walls Sealed
05000461/LER-1987-034, :on 870707,process Radiation Monitor Declared Inoperable Due to Failed Channel Functional Test Not Placed in Tripped Condition within 1 H.Caused by Personnel Error. Personnel Counseled Re Communications
05000341/LER-1987-041, :on 870329,accident Range Monitor Inoperable. Caused by Inadequate Sys Turn Over Following Preoperational Testing.Channel Parameters Will Be Verified Daily & Tech Spec Interpretation Issued
05000312/LER-1987-043, :on 870924,improper Monitoring of New Effluent Release Point Occurred.On 871005,air Sample Cartridge Not Delivered for Analysis Due to Fan A-546 Being Off.Events Caused by Personnel Error.Air Samples Taken
05000327/LER-1989-006, :on 890216,discovered That Auxiliary Bldg Waste Packaging Area Door Breached W/O Issuance of Breaching Permit.Caused by Inadequate Training & Programmatic controls.Plant-wide Dispatch Issued on 890223
05000424/LER-1987-041, :on 870623,reactor Trip Occurred Due to Automatic Trip of Main Turbine.Caused by Excessive Field Current Signal Due to Improperly Calibr Field Excitation Transducer.Transducer Recalibr
05000322/LER-1987-030, :on 870911,primary Containment Purge Filter Operated for 1,398 H Since Last Charcoal Sample Removed. Caused by Lack of Accurate Method for Tracking Run Time Hours.Schedule Activity Work Sheet Created
05000317/LER-1987-013, :on 870911,reactor Automatically Tripped.Caused by Loose Connection in Breaker Which Controls Pump Starts. Reactor Coolant Pump (RCP) Surge Capacitators Replaced W/ Inductors Located at RCP Breaker Switchgear
05000412/LER-1987-011, :on 870730,two Surveillance Procedures in Progress Requiring Channel IV Steam Pressure Bistables for Steam Generator 21C to Be in Tripped Condition.Caused by Personnel Error.Test Engineer Reassigned
05000336/LER-1987-004, :on 870202 & 0208,automatic Actuations of Emergency Safeguards Actuation Sys Resulted in Containment Purge Valve Isolations.Caused by Broken Window on Beta Scintillation Detector.Detector Replaced
05000312/LER-1987-040, :on 870817,discovered That Source Daily Check During Releases Via Regenerant Tank Pathway Not Performed Per Tech Specs.Caused by Inadequate Tech Spec Review. Procedures Revised & Temporary Changes Made
05000483/LER-1987-019, :on 870817,personnel Discovered That Local Leak Rate Test Not Performed on 870508 When Flanges Reinstalled. Caused by Inadequate Surveillance Procedure.Task Sheets, Tracking Schedule & Procedures Revised
05000328/LER-1987-008-01, :on 871127,w/unit in Mode 5,Train a Containment Ventilation Isolation Occurred.Caused by Spurious High Radiation Spike in Radiation Monitor.Special Task Force Group Established to Determine Root Cause
05000328/LER-1987-006-02, :on 870518,discovered Error in Core Cycle Exposure & Height Dependent Power Factor.Caused by Personnel Error in Utilization of Vendor Supplied Data.Qa Qualification of Incore Will Validate Program
05000482/LER-1987-021, :on 870516,hourly Fire Watch,Per Tech Spec 3.7.11,performed Late.Caused by Personnel Error.Signoff Will Be Added at End of Each Fire Watch Impairment Log to Ensure Verification by Fire Watch Personnel
05000317/LER-1986-007-01, :on 861011,automatic Actuation of Reactor Protection Sys on High Axial Shape Index Initiated Reactor Trip.Caused by Lack of Detailed Procedural Guidance for Specific Plant Conditions
05000388/LER-1986-019-01, :on 861218,22 & 25,facility Entered Limiting Condition for Operation 3.0.3 Three Times to Sample Wetwell. Caused by Off Normal Valve Lineup of Containment Radiation Monitoring Sys.Operating Strategy Reviewed
05000341/LER-1987-001, :on 870126,during Calibr Activities in RWCU Sys,Esf Isolation Actuation Received.Caused by Inadequate Communication Between Instrument Repairman & Shift Personnel.Personnel Counseled
05000269/LER-1986-012-04, :on 861015,water Supply Available to Standby Shutdown Facility (Ssf) Insufficient to Enable Ssf to Accomplish Function.Caused by Failure to Define Design Bases of Ssf.Listed Plant Mods Completed
05000213/LER-1986-023, :on 860518,nuclear Instrumentation power-range Channel 34 Spuriously Generated Dropped rod-load Runback Signal.Caused by Load Limiter Mechanically Binding.Load Limiter Clutch Adjusted
05000334/LER-1986-003, :on 860326,during Monthly Test for Diesel Generator,Area Smoke Detector Alarmed,But No Fire Alarm Received in Control Room.Caused by Two Inoperable Detectors. Test Procedure Revised
05000529/LER-1986-016-01, :on 860416,pressurized Heaters Operated in Condition Contrary to Tech Specs.Caused by Personnel & Procedural Error.Improper Amperage Calculation Formula Corrected
05000423/LER-1986-001, :on 860116,during Hot Standby Mode,Reactor Tripped Due to Safety Injection Signal from Rate Compensated Steam Line Low Pressure of Steam Generator A.Caused by Quick Opening of Atmospheric Steam Dump Valve
05000341/LER-1987-055, :on 871210,isolation of RCIC Sys Steam Line Occurred.Caused by Inadequacy in Sys Operating Procedure.Rev Made to Operating Procedure Which Directs Operator to Throttle Inboard & Outboard Isolation Valves
05000293/LER-1985-020, :on 850726,operations Personnel Notified by Chemistry Group That Emergency Diesel Fuel Oil Storage Tank a Test Results Did Not Meet Tech Spec Criteria.Caused by Personnel Error & Procedural Inadequacy
05000333/LER-1992-046, :on 921017,primary Containment Shutdown for Cooling Suction Isolation Valve Automatically Closed Due to Procedure Deficiency.Plant Procedures Will Be Revised to Reflect Changes to 10CFR50.72 & 10CFR50.73
05000334/LER-1985-007, :on 841130,during QC Insp of Hydraulic Snubbers,Oil Reservoirs to Four Snubbers Positioned So That Existence of Positive Fluid Head to Snubber Seals Could Not Be Verified.Two Snubbers Found Inoperable
05000364/LER-1984-012-01, :on 841026,reactor Tripped Due to General Warnings in Both Trains of Solid State Protection Sys. Caused by Operator Error During Operability Test.Operator Counseled
05000251/LER-1984-004-02, :on 840307,while Purging,Spurious Signal to Process Radiation Monitor R-11 Actuated Containment & Control Room Ventilation Sys Logic,Closing Purge Valve & Placing Ventilation Sys in Recirculation Mode
05000324/LER-1995-002-02, :on 950510,HPCI Sys Failed to Operate as Required During Performance of HPCI Periodic Test.Caused by End of Burnout.Verified Adequacy of Similar Resistors in Unit 1 & 2HPCI & RCIC Sys
05000293/LER-1991-011, :on 910604,inadvertent Primary Containment & Secondary Containment Isolation Signal Occurred Due to Util Licensed Operator Error.Responsible Engineer Counseled
05000325/LER-1991-011, :on 910424,unexpected Trip on Electrical Protection Assembly Output Breaker in Alternate Power Source Caused Power Loss to Bus B.Caused by Component Failure of Electrical Protection Assembly
05000446/LER-1994-013, :on 940817,four of Twenty Valves Tested Had Lift Settings Outside the Plus or Minus 1 Percent Setpoint Tolerance.Cause Not Determined.Setpoint Changes Request Submitted
05000325/LER-1994-004, :on 940126,loss of RPS a Bus Power & Associated ESF Actuations Occurred.Caused by Operator Error.Reviewed Event W/Involved Operator
05000382/LER-1994-009-01, :on 940218,SRO Discovered Object Hanging from Spent Fuel Handling Machine.Caused by Inadequate Barriers. Power Strip to Computer Deengergized
05000324/LER-1993-009-03, :on 931016,ADS Relays Energized Due to Volt Ohm Meter Improperly Set During Performance of Maint Surveillance Test
05000295/LER-1992-019-01, :on 921008,autostart of ESF Components Occurred During Safeguards Testing.Caused by Procedural Deficiency. Incorrect Switches Replaced & Technical Staff Electrical Group Performed Visual Insp of Other Switches
05000282/LER-1993-008, :on 930624,observed That Valve CV-31740, Instrument Air to Unit 1 Containment Closed Due to Failure of Coil in Solenoid Operated Pilot Valve.Valve Reopened Locally to Restore Instrument Air
05000293/LER-1993-002, :on 930225,RCIC Sys Declared Inoperable During Surveillance Testing.Caused by Galling of Valves Stem & Bonnet Chamber.Valve Stem & Bonnet Chamber Will Be Replaced & Parts Will Be Purchased Following Design
05000324/LER-1989-005-02, :on 890313,HPCI Removed from Svc Due to Limitorque Torque Switches Set Too High.Caused by Software Error Which Caused Indicated Output Torque to Read High. Setting Adjusted.Also Reported Per Part 21
05000346/LER-1994-005, :on 941103,RPS Channel 4 Response Times Exceeded.Caused by Incorrect Buffer Amplifier Module Ordered from Warehouse.Correct Buffer Amplifier Installed
05000341/LER-1989-008, :on 890316,emergency Equipment Cooling Water Sys Actuated During Surveillance.Caused by Personnel Error. Accountability Meeting Held Between Personnel Involved & Mgt.Potential Design Change Will Be Evaluated