05000454/LER-1998-018, Corrected LER 98-018-00:on 980912,inoperable Unit 1 DG Was Noted.Caused by Low Lube Oil Pressure Condition.Immediately Entered Into Lcoar for AC Sources TS 3.8.1.1,Action a
05000336/LER-1988-003, :on 880130,inadvertent Automatic loss-of-normal Power Actuation Occurred on Two of Engineered Safeguards Actuation Sys.Immediate Cause Not Apparent.Wiring Error Identified & Corrected
05000245/LER-1988-010, :on 881115,noticed That One of Hydraulic Snubbers Had No Visible Signs of Fluid in Reservoir.Caused by Small Crack at Base of Plastic Reservoir.Visual Insp of All Snubbers in Containment Performed
05000336/LER-1989-007, :on 890613,condensate Polishing Facility Radiation Monitor 2-CND-RE-245 Operated W/O Source Check. Caused by Personnel Error.No Corrective Action Taken as Check Added to Procedure Before Violation
05000336/LER-1987-010-01, :on 870730,inadequacies Identified in Fire Protection Coating on Raceway Support Structures in Main Cable Vault & Hallway Leading to Charging Pumps.Hourly Fire Watch Started & Automatic Sprinkler Installed
05000455/LER-1998-003-04, :on 980416,high RCS Activity & ESF Actuation Occurred.Caused by Inadequate RCS Cleanup & Weak Administrative Controls.Posted Area Surrounding Refueling Cavity as High Radiation Area
05000414/LER-1989-016, :on 890616,both Channels of Upper Range Reactor Vessel Level Instrumentation Found Inoperable.Caused by Supervision Assigning Unqualified Technician to Return Instrumentation to Svc on 890528
05000327/LER-1998-002-03, :on 980716,inadequate Surveillance Testing Was Discovered.Caused by Misinterpretation of ANSI Standard. Revised Appropriate Procedures to Provide Required Guidance
05000413/LER-1987-040, :on 871105,turbine-driven Auxiliary Feedwater Pump Automatically Opened & Steam Generator Blowdown Containment Isolation Valves Closed.Caused by Procedural Deficiency.Procedures Revised
05000266/LER-1998-019, :on 980615,discovered That Containment Hydrogen Monitors Lacked Environmentally Qualified Coating on Terminal Strips.Caused by Terminal Strips Being Disturbed W/O Subsequent Reapplication of Coating.Replaced Coating
05000461/LER-1989-010, :on 890206,train B of Standby Gas Treatment Sys Automatically Actuated While Power Restored to Div I,Class IE Ac Power Sys.Caused by Use of Incorrect Sequence for Power Restoration Leads.Work Plans Reviewed
05000295/LER-1997-020-02, :on 970908,identified That Main Steam Instrument Cabling Routed Through Main Steam Tunnels in Contradiction to Ufsar.Cause & Corrective Actions Will Be Submitted in Supplemental LER
05000298/LER-1997-013, :on 960807,plant Was Noted Outside Design Basis Due to Inadequate Scram Discharge Volume Mod.Inadequate Design Review May Have Caused Condition.Cause Is Unknown. Implemented Mod MP96-121 in May 1997
05000245/LER-1997-037-01, :on 970930,house Heating Boiler Ash Was Found to Be Slightly Contaminated.Caused by Unmonitored Release Path for Airborne Effluents IAW Requirements of TS 4.8.D.4. Restricted Boiler Use Until SE Was Performed
05000353/LER-1999-004-02, :on 990701,determined That Thirteen MSRVs Failed to Meet 1% Setpoint Tolerance Due to Setpoint Drift.Caused by Corrosion Induced Bonding Between Pilot Disc & Seat.All Fourteen Srvs Pilot Valves Were Replaced
05000352/LER-1999-005, :on 990611,RPS & ESF Actuations Were Noted. Caused by Personnel Error During Turbine Routine Testing. Revised Backup Overspeed & Power/Load Unbalance Test Routine Test Procedure.With
05000289/LER-1999-001-01, :on 990122,short Sections of Piping Caused by Misplacement of Sensing Elements & Insulation.Caused by Failure to Adhere to Vendor instruction.Re-installed Heat Trace Sys
05000413/LER-1999-004, :on 990310,operation Prohibited by TSs Was Noted.Caused by Incorrect TS Requirements for Cravs & Auxiliary Bldg Filtered Ventilation Exhaust Sys Actuation Instrumentation.Submitted Lar.With
05000259/LER-1997-004-04, :on 971010,discovered That RHR Swp LCO Is non- Conservative.Caused by Error in Preparation & Approval of Original TS 3.5.C.Will Submit TS Change to NRC to Remove non-conservatism from TS 3.5.C
05000346/LER-1997-016-01, :on 971217,monthly ECCS Valve Position SR Was Missed.Caused by Flow Path That Was Not Part of Contiguous ECCS Flow Path Envisioned for Compliance W/Ts 4.5.2.Verified Valves Open on 971222
05000348/LER-1999-002-02, :on 990527,Unit 1 Reactor Trip Occurred Following Loss of 1A SG Feedwater Pump.Caused by Personnel Error.Unit Was Stabilized in Hot Standby.With
05000424/LER-1998-006-02, :on 981008,auxiliary FW Train B Breaker Buckets Were Not Seismically Qualified.Caused by Personnel Error. Seismic Clips Were Secured & Event Will Be Addressed in Electricians Training.With
05000289/LER-1998-010-01, :on 980825,potential Violation of Design Criteria During Single Auxiliary Transformer Operation Occurred.Caused by Failure to Adequately Define Job Performance Stds.Temporary Change Notice Issued
05000454/LER-1997-003-02, :on 970218,equipment Hatch Gallery Was Not Properly Attached to Containment Structure.Caused by Original Construction Deficiency.Unit 1 Containment Equipment Hatch Gallery Will Be Restored
05000317/LER-1997-003-01, :on 970424,fuel Moved in Spent Fuel Pool Without Charcoal Absorber Banks Being in Svc.Caused by Personnel Error.Fuel Movement Suspended Until All Appropriate Personnel Could Be Trained
05000302/LER-1997-012, :on 970531,portions of Industrial Cooling Sys Failed to Meet Es Requirements.Caused by Design Error. Upgraded Associated Piping,Supports & Coolers Inside Containments Are Required
05000413/LER-1997-004-02, :on 970514,inadequate Surveillance Determined. Caused by Interpretation of Conflicting TS Requirements. Station Procedures Revised to Ensure TS Surveillance 4.5.3.2 Is Met
05000289/LER-1997-005-01, :on 970410,declared motor-operated Reactor Bldg Purge Valves Inoperable Due to Inadequate Closing Torque. Caused by Deficient Design Analysis.Will Perform Evaluation of Valve Specific Seating Torque Test Data
05000443/LER-1997-005, :on 970314,misposition of Main Steam Line Radiation Monitors Was Discovered.Caused by Human & Misjudgement Errors.Design Change Was Implemented to Relocate MSLRMs Approx 24 Inches Upstream
05000423/LER-1997-025, :on 970310,failure to Enter TS 3.0.3 Was Noted Upon Loss of Vital AC Bus VIAC-1.Caused by Failure to Address Inconsistency Between TS 3.3.2 & TS 3.8.3.1 During Development.Procedures Will Be Revised
05000245/LER-1997-017-01, :on 970222,failed to Meet TS 3.1.C, Reactor Protection Sys Power Monitoring. Caused by Personnel Error. Revised OP 344A to Delete Installation of Jumper
05000443/LER-1997-004, :on 970206,remote Shutdown Sys Circuits Were Not Tested Completely.Caused by Procedural Technical Inaccuracies Resulting in Required Testing Not Performed. Operability Determination Was Completed
05000354/LER-1996-024-01, :on 961029,two Redundant Vacuum Breakers on a Station Svc Water Sys Loop Were Tested & Found Inoperable Due to Accumulation of Deposits on Internal Moving Parts. Both Vacuum Breakers on a Station,Repaired
05000321/LER-1997-001-01, :on 970129,pressure Boundary Leakage Results in Condition Prohibited by Tss.Cause of Event Cannot Be Determined Conclusively.Maint Personnel Repaired Line.W/
05000482/LER-1996-015, :on 961023,failure to Comply with TS 3.6.1.1, Containment Integrity Occurred.Cause Under Investigation. TSC 033-85 Was Deleted & Removed from CR on 961112
05000213/LER-1996-028, :on 961016,containment Personnel Air Lock Hydraulic Sys Did Not Meet App J Criteria Due to Failure to Recognize Hydraulic Sys as Separate Penetration.Hydraulic Sys Penetrations Will Be Modified
05000443/LER-1996-010, :on 961125,response Time Testing of Main Steam Isolation & Reactor Trip Circuits Occurred.Cause of Event Not Determined.Operability Determinations for Sgpnrh & Prhpfr Have Been Completed
05000318/LER-1996-006, :on 961210,discovered EDG Had Been Inoperable for Six Days.Caused by Personnel Error.Checked Fuse Holder Covers,Conducted Tailgate Training & Revised Procedure Re Installation of Fuse Holder Covers
05000327/LER-1996-012-01, :on 960330,two Cold Leg Accumulator Sample Isolation Valves & Missing Data Sheet in Surveillance Package Were Inoperable.Caused by LCO Not Being Entered. Isolation Valves Were Tested
05000328/LER-1996-006-04, :on 961206,automatic Reactor Trip Occurred. Caused by Loss of Power to Start Bus 2A,start of Four EDG & Loading of EDG 2B-B.Refurbished Breaker Installed in 2A Start Bus & Breaker Tested Acceptable
05000325/LER-1996-007, :on 960609,high Pressure Coolant Injection Sys Declared Inoperable Due to Steam Supply Valve Packing Leak. Refurbished Valve & Corrected Off Center Condition
05000271/LER-1996-004, :on 960202,discrepancies Identified in App J Leak Rate Testing Program.Caused by Design Analysis Problem. Procedure Revised
05000266/LER-1996-008, :on 960806,inner Doors of Unit 1 Containment Upper Hatch Failed an Airlock Door Seal Test.Caused by Failure to Comply with Procedures TS-10A & TS-10A,App B. Containment Upper Hatch Repair Completed
05000301/LER-1996-001-01, :on 960518,reactor Trip Occurred Due to Spurious Closure of Turbine Stop Valves.Caused by Equipment Failure.Extensive Troubleshooting Performed,Valve Examined in Place,Removed & Replaced
05000328/LER-1996-002-05, :on 960822,discovered Failure to Properly Identify Steam Generator Tube May Have Exceeded Tech Spec Plugging Criteria.Caused by Misjudgement by Two Independent Analysts.Evaluation Performed
05000271/LER-1995-014, :on 950725,identified Deficiencies in Safe Shutdown Capability Analysis Resulted in Incomplete Implementation of 10CFR50 App R.Implemented Enhanced Awareness of Potential App R Vulnerabilities
05000354/LER-1996-016, :on 960427,unplanned High Pressure Coolant Injection Sys Inoperability Due to Blown Fuse & Trip Unit Card Failure.Caused by Shorted Capacitor.Trip Unit Card & Fuse Were Replaced
05000370/LER-1996-001-01, :on 960208,RWST Level Transmitter Frozen.Caused by Insufficient Equipment Monitoring.Integrity & Proper Operation of Refueling Water Level Transmitter Panels Verified During Routine Maint & Periodically Checked
05000327/LER-1996-002-01, :on 960215,SRs Associated W/Fire Protection Hose Stations Not Performed as Required by Ts.Caused by Inadequate Procedure Rev.Entered Action of LCO & Established Measures to Address Issue
05000259/LER-1992-002-05, :on 920324,reactor Protection Sys Experienced Unexpected Failure,Causing Actuation of Esf.Cause Not Determined.Bus 1B Placed on Alternative Power,Alarms Reset & ESF Actions Returned to Normal
05000328/LER-1985-004-02, :on 850215 & 17,reactor Trips Occurred Due to lo-lo Steam Generator Water Level.Caused by Personnel Error & Failed Filter Cartridge Cover.New Cover Installed & Personnel Counseled
05000382/LER-1995-006-04, :on 951207,failed to Provide Backup Overcurrent Protection Due to Personnel Error.Installed Backup Overcurrent Protection for Circuits & Tested Two Breakers
05000325/LER-1992-009, :on 920331,control Room Operator Noted Abrupt Increase in Indicated Oxygen Concentration on H2/O2 Analyzer & Pump Diaphragm Failed.Caused by Normal Wear.Fuel Oil Injector Pump Replaced.W/Undated Ltr
05000301/LER-1995-005-01, :on 951025,plugged 46 Tubes Due to Degradation in Roll Transition,Tubesheet Crevice & Tube Support Plate Regions.Performed Closeout Insps Following Maint of Each Sg
05000483/LER-1995-006, :on 951002,plant Had to Be Shutdown Due to Excessive RCS Leakage & FW Isolation Signal Due to High SG Level.Applied Weld Overlay Per ASME Code Case N-504
05000317/LER-1995-003-01, :on 950730 & 31,entered TS 3.0.3 Due to High Bay Water Temps.Administration Limit for Bay Water Temp Raised & Current Unit 1 & Unit 2 SW Tube Type HXs Will Be Replaced
05000259/LER-1992-002-02, :on 920302,unplanned ESF Actuations Occurred, Resulting from Short in Indicating Light Socket.Caused by Adequate Design Requirement.Esfs Reset to Normal Configuration
05000266/LER-1995-004, :on 950328,loss of Voltage Relays Not Calibr to TS Limits.Caused by Review of Setpoint Changes from Temporary Values to Permanent Was Less than Adequate.Ts 15.3.0 Was Entered at 0703
05000302/LER-1995-002, :on 950207,EDG Lops Signal Generated,Stripping Emergency Safeguards Bus a & Opening & Locking Out Supply Breaker (Brkr 3211).Caused by Personnel Error.Shop Personnel Counseled & Event Reviewed
05000318/LER-1994-005-01, :on 940924,reactor Trip Experienced Due to Main Turbine Governor Valve Opening.Wire on 21 Governor Valve LVDT Tightened & Wiring on All Other Unit 2 Main Turbine Throttle & Governor Valves Checked
05000260/LER-1991-007, :on 910409,ESF Actuation Occurred When Group 1 Primary Containment Isolation Initiated.Caused by Leaking Packing on Check Valve Differential Pressure Transmitters. Trapped Air Vented & Line Backfilled
05000271/LER-1991-002, :on 910215,discovered That Tech Spec Fire Protection Sys Surveillances Exceeded Specified Test Interval Since 860618.Caused by Misinterpretation of Test Interval.Training Provided
05000318/LER-1994-003-01, :on 940711,commenced Reactor Shutdown for Leak from Fatigue Crack in SIT Line.Support for Line Redesigned & Installed to Reduced Levels of Vibration to Acceptable Level & Similar Lines Examined
05000458/LER-1994-019, :on 940624,SSW Pumps Automatically Started During Surveillance Testing of Div II Remote Shutdown Control Circuitry.Caused by Procedural Deficiency. Surveillance Tp STP-200-0602 Will Be Revised
05000328/LER-1990-016-01, :on 901117,determined That Unit 2 Operated in Noncompliance W/Tech Spec 2.2.1 & LCO 3.3.1 Because of Nonconservative Calibr of Nis Intermediate Range Channels. Caused by Procedural Inadequacies
05000293/LER-1994-002, :on 940309,HPCI System Was Declared Inoperable Due to Inoperable Mov.Caused by Failure of Torque Switch. Plant Design Changes Will Be Generated to Make Torque Switch Replacement & Install New Spring Pack
05000285/LER-1993-019, :on 931209,AFW Pumps Rendered Inoperable Due to Inappropriate Testing Lineup.Surveillance Test SE-ST-AFW-3005 Will Be Revised
05000309/LER-1990-007, :on 901002,power Range Safety Channels Level I Bistables Found to Be Out of Calibr
05000338/LER-1993-017, Lr 93-017-00:on 930616,containment Hydrogen Analyzer Heat Trace Channel Calibration Not Performed on Staggered Test Basis Due to Inadequate Implementation of TS Amend.Test Procedure Satisfactorily Performed
05000325/LER-1993-003-03, :on 930608,RPS MG a Tripped,Resulting in Successful ESF Actuations & Isolations Due to Defective Procedure.Voltage Adjust Potentiometer for MG a Voltage Regulator Replaced on 930617
05000293/LER-1993-014, :on 930531,automatic Scram Occurred,Resulting from Operation of Auxiliary Transformer Differential Relay During Power Ascension.Uat Phase B & C Differential Relays Left Interchanged as Investigative Aid
05000456/LER-1993-002-05, :on 930201,identified Nonconservatism in Heatup/Cooldown & Cold Overpressure Protection PORV Setpoint Curves.Caused by Design Deficiency.Curve Book & Surveillance Procedures Revised
05000321/LER-1994-002-03, :on 940325,personnel Error Resulted in ESF Actuations.Personnel Counseled & Trained & EDG Control Circuit Wire Repaired
05000324/LER-1991-001-03, :on 910125,reactor Scram Occurred During Calibr of Feedwater Computer Point.Caused by Incorrect Procedure in Summary Sheet.Maint Procedures Reviewed & Revised
05000366/LER-1989-008-03, :on 891102,RWCU Sys Experienced Partial Primary Containment Isolation Sys Group 5 Isolation Involving Valve 2G31-F004.Caused by Component Failure of Relay 2G31-R616D. Relay Replaced
05000272/LER-1996-011-02, :on 960620,pressurizer Safety Relief Valves Were Found Outside of TS Tolerance.Caused by Minor Testing Instrument Error.Valves Were Refurbished & Successfully Retested to within TS Tolerance
05000400/LER-1997-012, :on 970505,determined That Previous Auxiliary Control Panel Had Not Verified Operability of Interposing Relays.Caused by Misinterpretation of Tss.Reviewed Other Remote Shutdown Panel Transfer Circuitry
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
05000315/LER-1988-002-01, :on 880326,ice Buildup in Ice Condenser Flow Passages Declared Inoperable.Caused by Sublimation of Ice or High Humidity in Containment Air.Flow Passages Manually Cleaned to Remove Frost
05000397/LER-1988-024, :on 880703,single Primary Containment Monitor Intermittently Exceeded 150 F Temp & Time Limit.Cause Contributed to Leaking Main Steamline Safety Relief Valves & Leaking Tailpipe Vacuum Breaker Valves
05000389/LER-1989-001-02, :on 890222,water Level in Spent Fuel Pool Raised High Enough to Flood Intake Ventilation Ducts Lining Perimeter of Pool,Rendering Ventilation Sys Inoperable. Caused by Personnel Error.Ductwork Drained
05000498/LER-2015-001, Regarding Manual Reactor Trip Due to Lowering Steam Generator Levels and Valid Auxiliary Feedwater System Actuation Following a Manual Main Turbine Trip
05000220/LER-2005-002, Re Fuel Moved with an Inoperable Source Range Monitor Due to Human Error Resulting in a Technical Specification Violation
05000413/LER-2003-004, A Containment Spray System Inoperable for Longer than Technical Specifications Allow Due to Heat Exchanger Fouling
05000277/LER-1998-007-02, :on 981107,failure to Meet TS & Associated LCO Requirments of Absolute Difference in APRM & Calculated Power of Less than 2% Was Noted.Caused by Substitute Valves Being Used.Removed Substitute Valves.With
05000454/LER-1997-013-03, :on 970522,valve Mistakenly Opened & Caused post-LOCA Leakage to Exceed Limit.Cause Unknown.Licensee Identified Affected Sys & Procedures That Vent or Open Affected Sys
05000461/LER-1997-011, :on 860929,failed to Verify Breaker Closed at seven-day Frequency Required by TS Due to Omission of Breaker from Surveillance Procedure.Caused by Inadequate Procedures.Revised Procedures
05000318/LER-1996-001-01, :on 960227,breakers 552-41,552-21 & 552-61 Tripped Open in Plant Switchyard.Caused by Failure of Auxiliary Relay Card in Breaker 552-41.Failed Relay Card Replaced