05000327/LER-1985-036-01, :on 850825,26,28 & 0913,hourly Fire Watch Not Performed within 1 H.Caused by Improper Shift Relief or Inaccessibility to Areas.Fire Watches Reestablished as Soon as Practical
05000336/LER-1995-045, :on 951214,plant Shutdown Initiated Due to Indeterminate Structural Integrity of Charging Valve 2-CH-435.Repaired Valve
05000400/LER-1988-013-02, :on 880603,emergency Bus 1A-SA Deenergized Resulting in Automatic Start of Emergency Diesel Generator 1A-SA.Cause Undetermined.Failure of Battery Room Ventilation Damper Traced to Sticking Limit Switch
05000400/LER-1987-042, :on 870709,wrong Fuses Pulled During Process of Placing Clearance OP-87-1290 Resulting in Automatic Reactor/ Turbine Trip.Caused by Personnel Error.Operator Training Conducted Re Fuse Labeling Conventions
05000400/LER-1990-018, :on 900823,loss of Component Cooling Water Inventory Occurred.Caused by Lifted Reactor Coolant Drain Tank HX Valve Caused by Incorrect Relief Valve Setpoint. Inlet Isolation Valve Administratively Closed
05000400/LER-1989-004, :on 890207,loss of All Three Circulating Water Pumps Resulted in Loss of All Flow to Main Condenser, Causing Reactor Trip.Caused by Air Entering Circulating Water Pump Seal Water Sys.Components Repaired
05000400/LER-1988-011-01, :on 880511,Westinghouse Notified Plant of Unanalyzed Condition Re Inadvertent Actuation of Low Temp Overpressure Protection Sys.Automatic Actuation Function Disabled & Permanent Mod Under Consideration
05000400/LER-1987-034, :on 870611,air Leakage by Inner & Outer Doors of Personnel Air Lock Excessive.Caused by Flat Spots on O-ring Seal.Seals on Inner & Outer Doors Replaced & Procedure OMM-001 Revised
05000400/LER-1987-033, :on 870607,experienced Trouble W/Engine Barring Device Not Rotating Engine as Required Using Plant Svc Air. Caused by Low Plant Svc Air Pressure.Mod Installed Attaching Engine Barring Device to Starting Air Tank Air
05000400/LER-1988-008, :on 880217,emergency Svc Water Pump Started Then Tripped.Caused by Problem W/Overcurrent Relay. Overcurrent Relay Replaced & Emergency Safeguards Sequencer Sys Test Procedure Revised
05000400/LER-1987-045, :on 870716,RCS Pressure Fell Below Accumulator Pressure,Initiating Partial Injection of All Three Accumulators.Caused by Reactor Operator Error.Operating Shift Disciplined & Procedure Revised
05000250/LER-1987-015, :on 870522,design Basis Reconstitution Revealed Potential Loss of HVAC in Inverter & Battery Rooms.Caused by Mods to Original Plant Design.Maint & Insp Procedures Implemented for Air Conditioning Units
05000250/LER-1987-014, :on 870519,while Unit in Mode 6,determined That Design Discrepancy Existed in Containment Spray Sys.Caused by Flow Orifice in Discharge Line Not Incorporated in Field. Design Mods Will Be Implemented for Correction
05000250/LER-1988-027, :on 881006,mechanic Found to Be Contaminated When Exiting Containment Bldg.Specific Cause Unidentified. Addl Temporary Controls Implemented & Area Mopped
05000250/LER-1989-009, :on 890519,design Inadequacy in App R Safe Shutdown Analysis Identified by Util Engineers.Caused by Design Inadequacy.Fire Watches Established for Unit 4 & Will Be Established for Unit 3
05000250/LER-1987-024, :on 870913,reactor Controls Manipulated by Nonlicensed Person Under Supervision of Licensed Operator. Caused by Personnel Error.Personnel Counseled
05000316/LER-1995-008-01, :on 950905,inadequate Procedural Guidance Resulted in Autostart of Essential SW Pump on Unexpected ESF Signal.Event Was Evaluated & Determined to Be of No Safety Significance
05000315/LER-1991-005, :on 910718,emergency Diesels Declared Inoperable When Design Documents Could Not Be Located to Demonstrate Capability of EDG to Withstand Effects of Tornado.Edg Room Fans Will Be Run
05000316/LER-1989-012, :on 890624,monthly Channel Checks Required by Tech Spec 3.3.3.6,Table 3.3-10 for Containment Water Level Instruments Not Included in Surveillance Procedure.Caused by Personnel Error.Procedure Revised on 890624
05000316/LER-1989-003, :on 890119,valve Stem Seal Leak Allows Air Into Sensor Capillary Tubing Causing Reactor Vessel Level Indication Sys Calibr Shift.Caused by Leakage of High Point Fill Valve Stem Seals
05000316/LER-1987-010-01, :on 870902,insps Revealed Frost & Ice Buildup on Lattice Frames of Greater That 3/8 Inch in 46 Flow Passages & 6 of 24 Ice Condenser Bays.Caused by Abnormal Degradation.Ice Condenser Defrosted
05000315/LER-1987-008, :on 870604,ESF Actuation Occurred Due to Extreme High Level in Steam Generator 12.Caused by Mispositioning of Both Level Controller & Feedwater Flow Selector Switch.Level Controller Refurbished
05000316/LER-1987-011-01, :on 871002,Train a Safety Injection Signal Occurred.Caused by Personnel Error.Safety Injection Signal Reset,Plant Returned to pre-event Status & Personnel Reminded to Reevaluate When Work Exceeds Scope
05000530/LER-1989-001, :on 890303,electrical Grid Disturbance Resulted in Main Generator Output Breakers Opening,Resulting in Reactor Power Cutback & Steam Bypass Control Sys Actuation. Caused by Malfunction in Subj Control Sys
05000528/LER-1989-006-01, :on 890731,containment Purge Isolation Actuation Signal Initiated Due to Loss of Power to Panel 1E-PNB-D26.Cause Not Identified.Power Restored & Radiation Monitor RU-38 Placed Back on Line
05000528/LER-1989-021, :on 891106 & 09,discovered That Locked High Radiation Area Gate Open & Unguarded,Contrary to Tech Spec 6.12.2 Requirements.Caused by Personnel Error.Gates Secured & Addl Locking Mechanisms Installed on Doors
05000528/LER-1989-005, :on 890412,determined That Deficiencies Identified by Control Components,Inc of Atmospheric Dump Valves Constituted Reportable Part 21 Condition.Caused by Improperly Seated Piston Ring.Valve Replaced
05000397/LER-1991-026, :on 910918,main Control Room Received Alarms, Indicating RWCU HX Room High Temp & RWCU Outboard Isolation Valve Automatically Closed.Caused by Failed Electric Component.Circuit Input Card Replaced
05000397/LER-1989-033, :on 890811,RWCU Isolation Occurred When Fuse in Power Supply to Leak Detection Monitor Blew,Giving False High Alarm Signal to Isolation Logic.Cause Unknown.Fuse Replaced & RWCU Sys Restored to Operation
05000397/LER-1988-033, :on 880907,determined That Tech Spec Re Control Room Emergency Filtration Sys Verification Not Performed Since Startup in Dec 1983.Caused by Personnel Error. Temporary Procedure Will Be Initiated
05000397/LER-1988-023, :on 880629,Tech Spec Violation of Secondary Containment to Outside Differential Pressure Occurred.Caused by Sys Configuration Error.Instrument Setpoint Change Request Initiated
05000397/LER-1988-032, :on 880905,inadvertent Containment Isolation of RCIC Sys Steam Supply Line Occurred While Reactor Pressure Held at 90 Psig.Caused by Personnel Error.Startup Halted & Excess Flow Check Valves Reopened
05000397/LER-1988-034, :on 880909,pipe Failure Caused by Introduction of Liquid Nitrogen Into Primary Containment Supply Purge. Inerting Nitrogen Supply Valve & Containment Supply Purge Shut to Terminate Containment Inerting
05000400/LER-1987-032, :on 870602,radiation Monitor REM-21WL-3541 Sample Chamber Instead of REM-21WS-354 Drained for Disconnection Leaving Monitor Inoperable.Caused by Personnel Error.Procedure HPP-495 Prepared
05000397/LER-1988-006, :on 880213,series of Reactor Pressure Vessel Level Transients Resulted in Low Reactor Protective Sys Actuation Following Manual Scram.Caused by Procedural Inadequacy.Procedures Modified
05000397/LER-1988-009, :on 880401,standby Gas Treatment Sys Tech Spec Surveillances Not Performed within Time Limits.Caused by Personnel Error.Personnel Counseled & Procedure Revised to Provide Guidance When Surveillance Exceeded
05000397/LER-1987-033, :on 871218,plant Tech Spec Sections 4.0.5 Re ASME Valve in-service Testing Requirements & 3.6.3 Concerning Containment Valve Operability Not Met.Caused by Personnel Error.No Corrective Action
05000389/LER-1986-011-02, :on 860709,during Full Power,Both Diesel Generators Simultaneously Taken Out of Svc.Caused by Personnel Error & Broken Roll Pin in Governor of Diesel Generator 2A2.Maint Personnel Counseled
05000400/LER-1992-012-02, :on 920802,one of Three Secondary Relays Failed to Actuate,Causing TS 3.0.3 to Be Entered.Caused by Failure of under-voltage Relay to Actuate.Procedure Will Be Revised to Provide Guidance for Tripped Condition