Pages that link to "05000278/LER-2003-001, Loss of Capability of the 10CFR.50 Appendix R Alternate Control Station"

The following pages link to 05000278/LER-2003-001, Loss of Capability of the 10CFR.50 Appendix R Alternate Control Station:

Displayed 6 items.

• 05000278/LER-2003-001 (redirect page) ‎ (← links)
  • 05000278/LER-2001-001 ‎ (← links)
  • IR 05000277/2003004 ‎ (← links)
  • 05000278/LER-1982-008, Forwards LER 82-008/01T-0.Detailed Event Analysis Submitted ‎ (← links)
  • 05000278/LER-1983-002, Forwards LER 83-002/01T-0.Detailed Event Analysis Submitted ‎ (← links)
  • 05000278/LER-1983-006, Forwards LER 83-006/01T-0.Detailed Event Analysis Submitted ‎ (← links)
  • 05000278/LER-1978-019, Forwards LER 78-019/01T-0 ‎ (← links)
  • 05000278/LER-1980-026, Forwards LER 80-026/01T-0 ‎ (← links)
  • 05000278/LER-1982-022, Revised LER 82-022/01X-1:on 821025-1102,RHR HX 3D Leaked Slightly Radioactive Water Into Intake Structure.Caused by Expansion Bellows Leak Between Inner Floating Head & Drain. HX Repaired ‎ (← links)
  • 05000278/LER-1983-011, Forwards LER 83-011/01T-0.Detailed Event Analysis Submitted ‎ (← links)
  • 05000278/LER-1983-008, Followup LER 83-008/01X-1:on 830214,during Refueling Outage, Surveillance Testing Indicated Combined Leakage for Listed Valves Exceeded Limits or Failed to Meet Requirements.Caused by Seat Surface Degradation ‎ (← links)
  • 05000278/LER-1983-012, Forwards LER 83-012/-01T-0.Detailed Event Analysis Encl ‎ (← links)
  • 05000278/LER-1983-005, Forwards LER 83-005/01T-0.Detailed Event Analysis Submitted ‎ (← links)
  • 05000278/LER-1983-007, Forwards LER 83-007/01T-0.Detailed Event Analysis Submitted ‎ (← links)
  • 05000278/LER-1998-004, Forwards LER 98-004-00 Re ESF Actuation of Rwcs Due to High Flow Signal During Sys Restoration on 980820 ‎ (← links)
  • 05000278/LER-1999-001, Forwards LER 99-001-00 Re 990312 ESF Actuation of Rcics Due to High Steam Flow Signal During Sys Restoration.Rept Submitted Per 10CFR50.73(a)(2)(iv) ‎ (← links)
  • 05000278/LER-1998-002, Forwards LER 98-002-00,reporting Failure to Meet TS Requirements for Unit 3 RCIC During Period When Overspeed Trip Function Could Have Resulted in Inadvertent Trip During RCIC Operation ‎ (← links)
  • 05000278/LER-1998-001, Forwards LER 98-001-00,re Failure of 3A Core Spray Pump to Meet TS 3.5.1 as Result of Foreign Matl Intrusion Into Pump Impeller Area ‎ (← links)
  • 05000278/LER-1999-004, Forwards LER 99-004-00 Re Multiple Unplanned ESF Actuations During Planned Mod Activities in Main Cr,Per Requirements 10CFR50.73(a)(2)(iv) ‎ (← links)
  • 05000278/LER-2023-002, Main Steam Isolation Valves Stroke Times Exceed Technical Specification Limit ‎ (← links)
  • 05000278/LER-2023-001, Standby Liquid Control Pump Inoperable for Greater than LCO Window Due to Gas Intrusion ‎ (← links)
  • 05000278/LER-1989-002-03, :on 890829,reactor Vessel lo-lo-lo Level Signal Generated Resulting in Unit 2 RHR Pump Trip Signal.Caused by Combination of Personnel Error & Degraded Equipment.Trip Alarms Cleared & Isolation Valve Replaced ‎ (← links)
  • 05000278/LER-1988-003, :on 880520 & 22,primary Containment Isolation Sys Group III Inboard Isolation & Half Reactor Scram Occurred on Startup Feed,Resulting in Breaker Trip.Caused by Voltage Fluctuations.Breakers Reclosed ‎ (← links)
  • 05000278/LER-1989-001-03, :on 890720,flow Estimate Not Performed When Reactor Bldg Exhaust Flow Recorder Made Inoperable.Caused by Procedure Not Requiring That Flow Rate Be Estimated within 4 H of Removing Recorder.Personnel Counseled ‎ (← links)
  • 05000278/LER-1998-003-03, :on 980328,identified Failure to Meet TS for IST Stroke Timing of Msivs.Caused by Incorrect Interpretation of Required Testing Frequency.Reset Subject Surveillances to Appropriate TS Frequency ‎ (← links)
  • 05000278/LER-1998-002-02, :on 980504,failure to Meet TS for Rcic,Was Revealed.Caused by Incomplete Procedural Guidance.Various Components Including Trip Tappet,Head Lever & Tappet Guide Were Replaced ‎ (← links)
  • 05000278/LER-1987-009-02, :on 871012,RHR Shutdown Cooling & LPCI Isolation Valve MO-3-10-25B Closed Unexpectedly During Testing.Caused by Deficient Procedure ST 1.3-3.Procedure Will Be Revised Prior to Startup ‎ (← links)
  • 05000278/LER-1987-008-02, :on 871005,containment Isolation Valves Automatically Closed.Caused by Personnel Error.Warning Signs for Compartment Doors Ordered & Signs Will Be Installed ‎ (← links)
  • 05000278/LER-1987-001, :on 870317,reactor Scrammed from 85% Power on High Neutron Flux Signals from Neutron Monitoring Sys.Caused by Spurious Electrical Noise Due to Malfunctioning Cabinet Cooling Fans.Cooling Fans Replaced ‎ (← links)
  • 05000278/LER-1987-007-02, :on 870829,HPCI Rendered Inoperable Due to Loss of Instrument Power.Caused by Deteriorated Relay Coil.Relay Replaced & Added to Preventive Maint Program to Be Replaced on 6-yr Interval ‎ (← links)
  • 05000278/LER-1987-010, :on 871026,opening of Reactor Vessel Level Instrument Resulted in Group I Isolation.Caused by Personnel Error.Valve Closed,Variable Leg Refilled & Normal Level Indication Restored.Craftsman Disciplined ‎ (← links)
  • 05000278/LER-1999-005-03, :on 990920,uplanned Esfas During Planned Mod Activitives in Main CR Were Noted.Caused by Inattention to Detail by Individuals Performing Work.All CR Mods Were Ceased to Allow Review of Mod Work Packages.With ‎ (← links)
  • 05000278/LER-1998-001-01, :on 971103,3A CS Pump Failed to Meet TS 3.5.1. Caused by Less than Adequate Focus on Foreign Matl Exclusion During 3R11 Suction Strainer replacement.3A CS Pump Was Disassembled,Matl Was Removed & Pump Was Reassembled ‎ (← links)
  • 05000278/LER-1999-004-03, :on 990901,3A RPS Bus Was Inadvertently Deenergized,During Planned Mod Activities on Main CR Panel. Caused by Electrician Failing to Self Check Work.All CR Work Was Ceased Immediately & Shutdown Meeting Held ‎ (← links)
  • 05000278/LER-1987-004-01, :on 870402,leak Rate of Inboard D MSIV Exceeded Tech Spec Limit.Msiv Will Be Inspected to Determine Cause of Leakage.Msiv Will Be Repaired & Retested Prior to Returning to Operable Status ‎ (← links)
  • 05000278/LER-1986-019-02, :on 860914,reactor Manually Scrammed Due to High Main Steam Line Radiation.Caused by Resin Injection When Pilter Demineralizer H Placed in Svc.Rwcu Sys Operated to Remove Impurities ‎ (← links)
  • 05000278/LER-1987-006-04, :on 870514,primary Isolation Sys Group 3 Outboard Isolation Occurred.Caused by Procedural Inadequacy & Operator Error.Procedure Revised ‎ (← links)
  • 05000278/LER-1986-024-01, :on 861108,partial Group V Primary Containment Isolation Occurred During Testing of RCIC Sys Steam Tunnel Temp Switch.Caused by Loose Wire Connection.Wire Tightened ‎ (← links)
  • 05000278/LER-1986-023-02, :on 861104,reactor Protection Sys Initiated Full Reactor Scram During Main Turbine Shell Warming Procedure.Caused by Inadequate Design & Operator Error. Procedure Revised ‎ (← links)
  • 05000278/LER-1986-022-02, :on 861030,manual Scram Occurred After Resin Injection.Caused by Resin Left in Demineralizer Outlet Plenum or Piping After Recent Filter Element Replacement. Maint Work Instructions Revised ‎ (← links)
  • 05000278/LER-1986-017-02, :on 860807 & 08,hourly Fire Watches Not Performed in Several Areas.Caused by Personnel Error. Security Personnel Counseled ‎ (← links)
  • 05000278/LER-1986-021-02, :on 861021,water Vol in Suppression Chamber Exceeded Max Tech Spec Limit.Caused by Delay in Performance of HPCI Surveillance Test.Procedure Will Be Revised to Record Water Level During Test ‎ (← links)
  • 05000278/LER-1987-001-02, :on 870317,unit Scrammed on High Neutron Flux Signals from Neutron Monitoring Sys.Caused by Malfunctioning Cabinet Cooling Fans Re Electrohydraulic Control Sys (EHC) Circuitry.Fans & EHC Cards Replaced ‎ (← links)
  • 05000278/LER-1999-003-03, :on 990814,HPCIS Was Declared Inoperable Due to Erratic Behavior Resulting in Loss of Single High Train Safety Sys.Caused by Weakness in Procedural Guidance. Readjusted Hydraulic Governor Needle Valve.With ‎ (← links)
  • 05000278/LER-1986-020-02, :on 861007,erroneous Signal in Feedwater Control Sys Generated Feedwater Transient Resulting in Reactor Low Water Level Scram.Caused by Poor Electrical Connection in Temp Element ‎ (← links)
  • 05000278/LER-1986-004-02, :on 860228,RHR Pump 3D Started Unexpectedly.On 860324,sequence of Events Occurred Again.Caused by Two Grounded Wires Inside Pump Breaker Compartment.Ground Wires Repaired ‎ (← links)
  • 05000278/LER-1987-003-02, :on 870331,RHR Sys Isolated Due to Inadvertent High Reactor Pressure Signal.Caused by Personnel Incorrectly Assessing Status of Shutdown Cooling Sys Due to Procedural Inadequacies.Procedures Will Be Revised ‎ (← links)
  • 05000278/LER-1999-002, :on 990406,failure to Maintain Alarmed Access Control to Safeguards Sys Vital Area Door Upon Completion of Scheduled Maint Was Noted.Caused by Noncompliance with Procedures.All Security Personnel Have Been Briefed ‎ (← links)
  • 05000278/LER-1999-002-01, Forwards LER 99-002-01 to Correct Title Contained in Box (4) of LER Coversheet Form.Rev Does Not Change Reportability Requirements or Any Other Info Contained in Original Submittal of LER ‎ (← links)
  • 05000278/LER-1986-018-01, :on 860811,reactor Protection Sys Initiated Full Scram on Low Water Level Condition.Caused by Electrical Fault in Circuit Breaker Compartment Due to Abraded Insulation of Cable.Circuit Breaker Replaced ‎ (← links)
  • 05000278/LER-1987-002-02, :on 870325,reactor Scram Occurred Due to Low Water Level.Caused by Lifting of Lead Electrohydraulic Control (EHC) During Troubleshooting in Main Turbine EHC Sys Circuitry.Lead Reconnected ‎ (← links)
  • 05000278/LER-1986-001, :on 860203,Group III Outboard Isolation Occurred & half-scram Signal Generated.Caused by Lowered Voltage When Recirculation Pump 2B Started.Alternate Feed to New Static Inverter May Be Changed ‎ (← links)
  • 05000278/LER-1986-015-02, :on 860624,w/unit at 100% Power,Rwcu Sys Automatically Isolated.Caused by Wiring Error Resulting in Blown Fuse in RWCU Sys Electrical Circuit.Fuse Replaced.Mod Initiated to Correct Wiring Deficiency ‎ (← links)
  • 05000278/LER-1988-006-02, :on 880624,partial Group II Outboard Isolation of Primary Containment Isolation Sys Occurred.Caused by Accidental Grounding of Terminal in Control Panel.Fuse 16A-F22 Replaced ‎ (← links)
  • 05000278/LER-1999-002-02, :on 990406,safeguard Sys to Unrelated Door Was Inadvertently Disabled by Security Alarm Station Operator. Caused by Noncompliance with Procedures & Less than Adequate Shift Turnover.Briefed Personnel on Event.With ‎ (← links)
  • 05000278/LER-1999-001-03, :on 990312,ESF Actuation of Rcics Occurred Due to High Steam Flow Signal During Sys Restoration.Temporary Change to Restoration Procedure Was Initiated to Open RCIC Outboard Steam Isolation Valve in Smaller Increments ‎ (← links)
  • 05000278/LER-1988-010-02, :on 880923,primary Containment Isolation Sys Group III Isolation Occurred Resulting from Unexplained Momentary Loss of Power to a Reactor Protection Sys Bus. Isolation Reset After Approx 4 H & 25 Minutes ‎ (← links)
  • 05000278/LER-1986-010-01, :on 860411,automatic Actuation of Reactor Protection Sys & Group 2 & 3 Isolations Occurred.Caused by Feedpump Min Flow Bypass Valves (AO-3139A,B & C) Failure Creating Low Reactor Water Level.Valves Fixed ‎ (← links)
  • 05000278/LER-1986-016-02, :on 860719,Group II & III Isolations Occurred Due to High Neutron Flux Scram When Startup Source 3 Lost. Caused by Switchyard Fault & Abnormal Configuration of Fault Detection Circuit ‎ (← links)
  • 05000278/LER-1986-007-02, :on 860305,during Performance of Routine Test RT 5.31, Crossaround Relief Valve Setpoint Check, Rod Sequence Control Sys Bypassed W/Reactor at Less than 21% Power.Caused by Procedure Inadequacy ‎ (← links)
  • 05000278/LER-1986-005-02, :on 860306,low Level Scram & Group II & III Isolations Occurred as Reactor Pressure & Level Adjusted. Caused by Decrease in Main Condenser Vacuum Due to Maint Performed on Pump Drive Shaft ‎ (← links)
  • 05000278/LER-1986-008-02, :on 860304,HPCI Sys Steam Supply Valve MO-3-23-14 Failed to Open During Test.Caused by Disloged Movable Contact on Culter-Hammer Device 538 Relay.Contact Repositioned ‎ (← links)
  • 05000278/LER-1998-009-01, :on 981227,unplanned Esfa Were Noted.Caused by Transformer Insulator Failure.Replaced Failed Insulator. with ‎ (← links)
  • 05000278/LER-1986-006-02, :on 860304,control Room Annunciator Core Spray Sys I Logic Power Failure Alarmed.Caused by Blown Fuses on Core a Spray Logic Due to Grounded Wires.Fuses Replaced ‎ (← links)
  • 05000278/LER-1986-003, :on 860219,partial Containment Isolation Occurred When Plant Operator Removed Wrong Fuse While Applying Blocking Permit.Caused by Loose Fuse Label Strip. Label Secured W/Adhesive ‎ (← links)
  • 05000278/LER-1986-012-02, :on 860426,full Scram Occurred While Testing 500-kV Line Fault Detection Circuit.Caused by Personnel Error.Personnel Instructed to Exercise More Caution in Performance of Tests ‎ (← links)
  • 05000278/LER-1985-023, :on 851117,primary Containment Isolation Sys Valves Would Not Open.Caused by Personnel Removing Wrong Fuse During Maint.Fuse F3 Installed & Isolation Reset.W/ ‎ (← links)
  • 05000278/LER-1986-013-02, :on 860426,neutron Monitoring Scram Occurred. Caused by Personnel Error While Performing Functional & Calibr Check of intermediate-range Monitors.Operator Disciplined ‎ (← links)
  • 05000278/LER-1986-014-01, :on 860426,w/unit Shut Down,Scram Discharge Vol High Level Scram Occurred.Caused by Personnel Error.Operator Disciplined ‎ (← links)
  • 05000278/LER-1985-015-02, :on 850930,combined Leakage of Type B & C Containment Leak Tests Exceeded Allowable Leak Rate Limit. Cause Will Be Investigated During Valve Insp.Valves to Be Repaired & Retested ‎ (← links)
  • 05000278/LER-1998-005-03, :on 981025,inadvertent Unit 3 Electrical Bus E33 Trip (Esfa) During Performance of Unit 2 Electrical Bus E32 Surveillance Test Was Noted.Caused by Personnel Error. Sp S12M-54-E32-XXF4 Was Completed.With ‎ (← links)
  • 05000278/LER-1986-011-02, :on 860425,partial Group III Isolation Occurred Due to Blown Fuse in Primary Containment Isolation Sys.Cause Unknown.Fuse 16A-F20 Replaced ‎ (← links)
  • 05000278/LER-1988-003-02, :on 880520 & 22,primary Containment Isolation Sys Inboard Isolation & Half Reactor Scram Occurred.Caused by Reactor Protection Sys (RPS) Being Lightly Loaded.Rps Alternate Feed Breakers Reclosed ‎ (← links)
  • 05000278/LER-1988-001-02, :on 880408,primary Containment Isolation Sys Actuated During Switching of 4kV Emergency Bus Feed.Caused by Lack of Procedural Guidance & Training.Procedures Revised ‎ (← links)
  • 05000278/LER-1988-002-01, :on 880507,primary Containment Isolation Sys Group II RWCU Isolation Signal Generated as Result of Loss of Power to Temp Switch.Caused by 4-3R4 Tie Breaker Malfunction.Tie Breaker Removed & Serviced ‎ (← links)
  • 05000278/LER-1988-008-02, :on 880829,primary Containment Isolation Sys Group III Inboard Isolations Occurred as Result of Reactor Protection Sys Feed Breaker Trips.Caused by Undervoltage Relay Out of Calibr.Relays Calibr ‎ (← links)
  • 05000278/LER-1988-009-02, :on 880831,feeder Breaker to Emergency Bus E-2 Tripped & Power Lost to Bus Initiating Start & Loading of Generator.Probably Caused by Electricians Working in Cubicle Released for Work ‎ (← links)
  • 05000278/LER-1988-002-02, :on 880507,primary Containment Isolation Sys Group II RWCU Isolation Signal Generated as Result of Loss of Power to Temp Switch.Caused by Tie Breaker Malfunction. Tie Breaker Removed from Svc & Inspected ‎ (← links)
  • 05000278/LER-1988-005-03, :on 880613,RWCU Outboard Isolation Valve Logic Actuation Occurred on False Sys High Flow Signal.Caused by Small Piece of Insulation on Differential Pressure Indicating Switch Cable Missing ‎ (← links)
  • 05000278/LER-1987-001-03, :on 880408,actuation of Primary Containment Isolation Sys Occurred During Switching of 4 Kv Emergency Bus Feed.Caused by Lack of Procedural Guidance & Training for Operators.Training Bulletin Issued ‎ (← links)
  • 05000278/LER-1998-004-03, :on 980820,automatic RWCU Isolation Occurred While Placing B RWCU Sys Demineralizer in Svc.Caused by less-than-adequate Control of Equipment.Isolated B Demineralizer & Returned RWCU Sys to Svc ‎ (← links)
  • 05000278/LER-1988-007-02, :on 880712,partial Group II Outboard Isolation of Primary Containment Isolation Occurred.Caused by Fuse Failure.Fuse Replaced & Isolation Reset ‎ (← links)
  • 05000278/LER-1985-023-02, :on 851117,when Control Room Operator Proceeded to Establish Shutdown Cooling,Suction Valves to Sys Would Not Open.Caused by Plant Operator Removing Wrong Fuse While Applying Maint Permit ‎ (← links)
  • 05000278/LER-1985-021-02, :on 850826,w/unit in Refuel Outage & No Fuel in Reactor Vessel,Reactor Protection Sys Initiated Full Logic Actuation Signals.Caused by Personnel Inadvertently Bumping intermediate-range Monitor Cables ‎ (← links)
  • 05000278/LER-1985-025-01, :on 851101,Tech Specs Violated Due to Inoperable Snubbers.Caused by Procedure Not Indicating That CRD Sys Considered Inoperable Pending Repair of Inoperable Snubbers.Procedures Revised ‎ (← links)
  • 05000278/LER-1988-004-02, :on 880613,discovered That Dampers in Emergency Bus Room Ventilation Duct Penetration Would Not Close.Caused by Ventilation Diffuser Located in Damper Track.Fire Watch in 4 Kv Switchgear Room Continued ‎ (← links)
  • 05000278/LER-1988-005-02, :on 880613,RWCU Outboard Isolation Valve Logic Actuation Occurred on False Sys High Flow Signal.Caused by Equipment Failure.Insp & Rework of Class 1E Splices & Cables Performed.Isolation Reset ‎ (← links)
  • 05000278/LER-1994-006-03, :on 941110,identified That Flow Input Signals to APRMs Reading Higher than Actual Core Flow Conditions. Caused by Change in Plant Operating Strategy.Aprms Adjusted ‎ (← links)
  • 05000278/LER-1997-003-01, :on 970404,TS Noncompliance Due to Loss of 3C RFP High Water Level Trip,Occurred.Caused by Failure to Correlate Turbine/Reset Light Problem to Inoperability. Operating Shift Procedures Revised ‎ (← links)
  • 05000278/LER-1986-009-02, :on 860318,manual Scram Occurred.Caused by Series of Personnel Errors Involving Failure to Withdraw Correct Control Rod & Verify Proper Position of Control Rod. Personnel Counseled & Procedures Revised ‎ (← links)
  • 05000278/LER-1985-015, :on 850930,total Leakage of Type B & C Test Exceeded Leak Rate Limit.Caused by Several Valves Tested W/ Excessive Rates Contributing to Total.Valve Repaired & Retested Prior to Returning Unit to Operation ‎ (← links)
  • 05000278/LER-1986-003-02, :on 860219,partial Containment Isolation Occurred When Operator Removed Wrong Fuse While Applying Blocking Permit.Caused by Misleading Fuse Label & Lack of Adequate Operator Attention.Fuse Label Secured ‎ (← links)
  • 05000278/LER-1985-013, :on 850726,crack Indications Found in 40 RHR & Recirculation Piping Welds.Caused by Igscc.Eighteen Weld Overlays Repaired.Recirculation Inlet Safe Ends to Be Replaced During Next Refueling Outage ‎ (← links)
  • 05000278/LER-1985-020-02, :on 851120,RHR Pump C Tripped & Caught Fire. Caused by Failed Impeller Eye Wear Ring.Fire Extinguished & New Wear Rings Installed ‎ (← links)
  • 05000278/LER-1985-030-01, :on 851217,reactor Protection Sys Initiated Full Scram Due to False Intermediate Range Monitor (IRM) High Flux Signal.Caused by Accidental Bumping of IRM Cable. Sys Logic Reset ‎ (← links)
  • 05000278/LER-1986-002-02, :on 860217,RWCU Sys Isolated While Unit in Shutdown Mode.Caused by Deenergization of RWCU Sys Nonregenerative HX Outlet Temp Switch by Technicians.Design Change Being Considered ‎ (← links)
  • 05000278/LER-1985-029-01, :on 851213,RWCU Sys Isolated & Pump Tripped While Sys in Operation.Caused by Blown Fuse in RWCU Sys Logic.Fuse Replaced ‎ (← links)
  • 05000278/LER-1985-018-02, :on 840711,fault Occurred in cross-tie Between North & South Substations During Lightning Storm.Caused by Insulator Strip Flashover Due to Lightning Strike.Offsite Power Restored to Plant Startup Bus ‎ (← links)
  • 05000278/LER-1985-019-02, :on 851116,RWCU Sys Isolated on Unexpected High Temp Signal.Caused by Instrument Technicians Troubleshooting Wrong Temp Element on RWCU sys.TE-3-12-98 Leads Reconnected & RWCU Reset ‎ (← links)
  • 05000278/LER-1997-001, :on 970122,determined Plant Thermal Power Exceeded 100% Due to Out of Tolerance Test Equipment.Retired Test Apparatus from Future Use & Will Review and Revise Procedures for Feedwater Temp Instruments ‎ (← links)
  • 05000278/LER-1985-021-01, :on 850930,motor-driven Pump Left Out of Svc for More than 7 Days.Caused by Personnel Failure to Indicate on Checklist When Pump Required to Be Returned to Svc. Checklists Revised ‎ (← links)
  • 05000278/LER-1986-001-02, :on 860203,primary Containment Isolation Sys Group Ii/Iii Outboard Isolation Occurred.Caused by Starting Large Pump Motor While Motor Generator Set Out of Svc. Alternate Feed Changed to Static Inverter ‎ (← links)
  • 05000278/LER-1985-014-02, :on 850826,during in-vessel Inservice Insp Program,Crack Indication on 240 Degree Azimuth Core Spray Supply Junction Box Discovered.Caused by Intergranular Stress Corrosion.Brackets Installed ‎ (← links)
  • 05000278/LER-1997-002-02, :on 970309,manual Scram Occurred Due to Loss of Forced Reactor Core Circulation at Power as Result of 13kv Feeder Breaker Auxiliary Switch Failure.Auxiliary Switch Assembly Was Cleaned & Lubricated ‎ (← links)
  • 05000278/LER-1985-021, :on 850930,determined That Motor Driven Fire Pump Left Out of Svc for More than 7 Days.Caused by Personnel Error.During Slit Removal,Steps Will Be Taken to Reduce Amount of Time Fire Pump Out of Svc ‎ (← links)
  • 05000278/LER-1985-028-01, :on 850811,12,0906 & 25,while in Refuel Outage & W/Reactor Vessel Head Removed,Primary Containment Isolation Sys Initiated Various Isolations.Caused by outage- Related Work ‎ (← links)
  • 05000278/LER-1985-027-01, :on 851203 & 04,shutdown Cooling Suction Valves Closed.Caused by Ground in RHR Sys Logic Resulting from Pinched Wire in Differential Pressure Indicating Switch 3-10-121A.Switch Repaired ‎ (← links)
  • 05000278/LER-1985-017-02, :on 851018,reactor Protection Sys Initiated Full Scram Signal Due to False intermediate-range Monitor High Flux Signal.Caused by Personnel Bumping Cable. Technicians Made Aware of Event ‎ (← links)
  • 05000278/LER-1985-026-01, :on 851203,shutdown Cooling Suction Valves Closed as Result of Isolation Signal & RHR Pump Tripped. Caused by Removal of Wrong Fuse.Trips Reset After Fuse Reinstalled.Personnel Counseled ‎ (← links)
  • 05000278/LER-1985-016-03, :on 851018,scram & Group I-III Isolations Occurred Due to Inadvertent Deenergization of Reactor Protection Sys & Primary Containment Isolation Sys Logic. Caused by Procedural Error ‎ (← links)
  • 05000278/LER-1985-024-02, :on 851125,RWCU Received Unexpected Isolation Signal.Caused by Error on Blocking Permit Which Required Removal of Fuse Not Associated W/Work Being Performed. Operator Counseled ‎ (← links)
  • 05000278/LER-1985-022-02, :on 850911,reactor Protection Sys Initiated Full Logic Actuation Signal Due to False Scram Discharge Vol High Level Signal.Caused by Personnel Inadvertently Bumping Switch.Protection Sys Logic Reset ‎ (← links)
  • 05000278/LER-1985-012-01, :on 850807,during off-loading of Reactor Fuel Core,Peripheral Fuel Bundle Isolated from Source Range Monitor.Caused by Inadequate Temporary Procedure Change & Personnel Error.Procedure Modified Further ‎ (← links)
  • 05000278/LER-1985-011, :on 850621,discovered That Fire Watch Not Established for Fire Barriers Between MSIV Room & Torus Room,Per Tech Specs.Caused by Error in Design Drawings & Personnel Oversight.All Drawings Reviewed ‎ (← links)
  • 05000278/LER-1985-011-01, :on 850621,fire Watch Not Established for Degraded Fire Barrier.Caused by Design Drawing & Personnel Errors.Fire Watch Established & Penetration Seal Drawings Corrected.Penetrations Will Be Sealed ‎ (← links)
  • 05000278/LER-1992-002, :on 920117,discovered That DW Oxygen Concentration Level Exceeded Value Specified in Ts,Due to an Analyzer Failure.Round Sheets Have Been Revised to Include Instrument Nitrogen Compressor Run Times ‎ (← links)
  • 05000278/LER-1981-011-03, /03L-0:on 810307,seven MSIVs Failed Individual Tech Spec Leakage Limits.Single Valves Failed on HPCI 2-inch Turbine Exhaust Line.Test Taps Failed on Reactor Core Isolation Cooling 10 & 2-inch Exhaust Lines.Cause Unknown ‎ (← links)
  • 05000278/LER-1981-006-03, /03L-0:on 810227,core Spray Logic Sys B Failed. Caused by Blown Fuse Due to Grounded Lug on Core Spray Pump Circuit Breaker D Latch Check Switch.Circuit Breaker Replaced & Lug on Grounded Circuit Breaker Repositioned ‎ (← links)
  • 05000278/LER-1981-007-03, /03L-0:on 810206,main Steam Line Monitor a Indicated Low Level Radiation Resulting in Trip Setpoint Above Tech Spec Limit.Caused by Instrument Zero Drift. Monitor Calibr & Returned to Svc ‎ (← links)
  • 05000278/LER-1992-009-03, :on 921128,HPCI Sys Found to Be Inoperable When Flow Controller Output Signal 0% Instead of Expected 100%. Caused by Failed HPCI Flow Controller.Replacement of Type Flow Controller W/Like Kind Will Be Evaluated ‎ (← links)
  • 05000278/LER-1980-005-03, /03L-0:on 800207,during Surveillance Test,Setpoint of DPIS 3-13-84,reactor Core Isolation Cooling Turbine Steam Supply High Flow Sensor Found to Be 10 Inches of Water Greater than Tech Spec.Caused by Setpoint Drift ‎ (← links)
  • 05000278/LER-1979-041-03, /03L-0:on 791210,while Shut Down for Maint, Feedwater Flush Valve MO3-2-38A Failed to Close During ST 1.3.1.Caused by Improper Operation of Limit Switch.Switch Cleaned & Adjusted ‎ (← links)
  • 05000278/LER-1979-040-03, /03L-0:on 791206,during Routine Testing,Core C Spray Pump Discharge Pressure Switch PS3-14-44C Found to Be 9.0 Psig Above Tech Spec Limits.Caused by Setpoint Drift. Switch Was Recalibr,Tested & Returned to Svc ‎ (← links)
  • 05000278/LER-1979-021-03, /03X-1:on 790630,during Surveillance Testing,Main Steam Sample Line Inboard Isolation Valve Failed to Close. Probably Caused by Valve Packing Binding or Solenoid Valve Sticking While Valve Was at High Temp ‎ (← links)
  • 05000278/LER-1985-010-01, :on 850410,diesel Generators E-1 & E-3 Started & Drywell Coolers Tripped After Receiving False Reactor Low Level Signal.Caused by Defective Test Equipment Used During Surveillance Test.Generators Shut Down ‎ (← links)
  • 05000278/LER-1985-009-01, :on 850328,insp Plate Discovered Missing from Standby Gas Treatment Sys Suction Plenum,Affecting Secondary Containment Capacity.Caused by Maint Personnel Removing Plate for Fan Insp.Plate Reinstalled ‎ (← links)
  • 05000278/LER-1992-008-03, :on 921015,full PCIS Group I Actuation Occurred Which Caused Reactor Scram.Caused by Unexpected Actuation of Isolation Pressure Switches.Pcis & RPS Scram Logic Reset & Affected Sys Restored ‎ (← links)
  • 05000278/LER-1985-008-01, :on 850313,suppression Pool Water Level Rose to 15.3 ft,0.4 Ft Above Tech Spec Limit.Caused by Operator Mistakenly Opening Torus Test Bypass Valve.Torus Pump Used to Lower Water Level & Operator Disciplined ‎ (← links)
  • 05000278/LER-1992-006-03, :on 921002,plant Determined to Be Outside Design Basis Due to Potential Unisolatable Steam Line.Caused by Valves Incapable of Closing.Valve Motor & Spring Pack Replaced ‎ (← links)
  • 05000278/LER-1996-002-03, :on 960624,room Cooler Associated w/3C LPCI Pump Discovered Inoperable.Caused by Inadequate Post Maint Testing.Room Cooler Fan Motor Wiring Corrected.Provided Staff W/Info Re Breaker Configuration Control ‎ (← links)
  • 05000278/LER-1985-007-01, :on 850301,during Startup from Maint Outage at 30% Power,Reactor Scrammed from Main Condenser Low Vacuum. Caused by Leak on Feedwater Heater A2 Shell Side Relief valve.Leak-off Plug Installed ‎ (← links)
  • 05000278/LER-1996-001-03, :on 960529,HPCI Turbine Control Valve Failed to Open as Expected During Performance of Routine Test O-023A-450-3.Caused by Failed Solder Connection on HPCI Flow.Solder Connection Repaired ‎ (← links)
  • 05000278/LER-1985-006-01, :on 850220,RCIC Inboard Steam Isolation Valve Mo 3-13-15 Found Fitted W/Incorrect Limitorque Operator.No Addl Unsatisfactory Operators Found.Valve Fitted W/Correct Operator ‎ (← links)
  • 05000278/LER-1984-015-02, :on 841126,HPCI Turbine Exhaust Rupture Diaphragm Alarm Annunciated.Caused by Failure of Inner Rupture Disk PSD3-23-6.Rupture Disk Replaced ‎ (← links)
  • 05000278/LER-1985-005-01, :on 850129,total Combined Leakage of Types B & C Tests Exceeded Allowable Leak Rate Limit.Valves W/Unacceptable Leak Rates Repaired & Retested ‎ (← links)
  • 05000278/LER-1984-013-01, :on 840921,during Surveillance Test,Hpci Turbine Exhaust Rupture Diaphragm Alarm Annunicated Following Startup of Turbine.Caused by Ruptured Inner Rupture Disc PSD3-23-6.Disc Replaced ‎ (← links)
  • 05000278/LER-1992-007-03, :on 921004,discovered That Eight Daily Instrument Surveillance Checks Not Performed Per Ts,Due to Three Pages Inadvertently Excluded During Copying Process. Instrument Checks Performed & Acceptable ‎ (← links)
  • 05000278/LER-1985-003, :on 850109,during Surveillance Testing of HPCI Logic Sys,Hpci Turbine Could Not Be Tripped & Declared Inoperable.Caused by Relay Piston Binding Due to Paraffin on Piston.Piston Cleaned ‎ (← links)
  • 05000278/LER-1985-001-02, :on 850101,w/plant at 85% Power,Inverter Supplying Power to HPCI Instrumentation Failed.Caused by Three Failed Microfared Capacitors.Hpci Declared Inoperable Until Failed Inverter Replaced ‎ (← links)
  • 05000278/LER-1992-004-03, :on 920625,HPCI Sy Declared Inoperable Due to High Water Level in Turbine Casing.Level in HPCI Turbine Exhaust Drain Pot Will Be Monitored & Maintained at Normal Level Using Drain Valve ‎ (← links)
  • 05000278/LER-1991-017-01, :on 910924,MSRV SV Wiring Insulation Was Discovered to Be Degraded Due to Improper Installation. Caused by Temp Increase from Insulation Installation.Thermal Insulation Was Properly Reinstalled ‎ (← links)
  • 05000278/LER-1985-016, :on 841224,HPCI Turbine Exhaust Rupture Diaphragm Alarm Annunciated During Operation of HPCI Turbine.Caused by Failure of Inner Rupture Disk PSD3-23-6. Rupture Disk Replaced ‎ (← links)
  • 05000278/LER-1984-014-01, :on 841114,reactor Scram Occurred While Attempting to Replace Recirculation Pump B.Caused by Power Spike from Cold Water from Idle Recirculation Loop. Operating Procedure for Pump Startup Revised ‎ (← links)
  • 05000278/LER-1985-002, :on 850220,automatic Start Capability of RHR & Core Spray Sys Defeated to Permit Repairs to MSIVs W/O Reactor Mode Switch in Refuel Position.Caused by Failure of Operator to Assure Switch in Shutdown Position ‎ (← links)
  • 05000278/LER-1995-007-02, :on 951202,main Turbine Trip Occurred Caused by Full Reactor Scram.Replaced Mechanical Trip Solenoid Valve Terminal Strip That Caused Initial Ground ‎ (← links)
  • 05000278/LER-1992-005-03, :on 920714,offgas Recombiner Low Flow Condition Caused Main Condenser Vacuum to Begin Decreasing & Small Scram Initiated.Caused by Loose Pressure Control Valve Feedback Linkage.Linkages Replaced ‎ (← links)
  • 05000278/LER-1985-004-01, :on 850126,during Surveillance Testing,Hpci Turbine Exhaust Rupture Diaphragm Alarm Annunciated Following Startup.Caused by Failed Rupture Inner Disc PSD3-23-6.Disc Replaced ‎ (← links)
  • 05000278/LER-1984-010-01, :on 840816,loss of Power to Portion of Primary Containment Isolation Sys Outboard Isolation Logic Caused Partial Actuation.Caused by Grounded Leads on Primary Side of Unit 2 Pump Transformer A.Logic Reset ‎ (← links)
  • 05000278/LER-1984-011-01, :on 840821,sudden Runback of Three Reactor Feed Pumps Resulted in Reactor Low Level Scram,Groups I,Ii & III Isolations & Automatic Initiation of HPCI & Rcic.Caused by Intermittent Failure of Component ‎ (← links)
  • 05000278/LER-1992-003-03, :on 920505,IRM Failed Upscale Which Resulted in Reactor Scram Due to Defective Undervessel Connector. Measurements Were Performed on All Defective IRM Channels ‎ (← links)
  • 05000278/LER-1984-009-01, :on 840801,HPCI Sys Declared Inoperable Due to Identification of Mechanical Failure of Second HPCI Steam Supply Line Hanger 3-23-DBN-S4.Cause Unknown.Hanger Repaired & HPCI Returned to Svc ‎ (← links)
  • 05000278/LER-1990-003-02, :on 900306,reactor Scram Occurred Due to Main Turbine Trip.Caused by Improper Setting of Timer Due to Deficient Test Procedure.Procedure Revised ‎ (← links)
  • 05000278/LER-1995-005-03, :on 951108,three of Eleven MSRVs Did Not Lift within TS +1% Tolerance Due to Small Drift in Setpoint of Valves.Refurbished Valves Have Been Properly Setup at Test Facility & Install for All MSRVs & SVs ‎ (← links)
  • 05000278/LER-1995-006-03, :on 951025,TS Violation Occurred Due to Licensed Reactor Power Exceeded.Corrected Program That Calculates TS 8 H Shift Average CTP ‎ (← links)
  • 05000278/LER-1995-004-03, :on 951028,drywell Floor Drain & Equipment Sump Pump Was in TS Violation.Caused by Both Floor & Equipment Drain Sump Pumps Not Operating in Automatic Mode.Provided Pertinent Info from Event to Personnel ‎ (← links)
  • 05000278/LER-1991-018-02, :on 911216,an Isolation of Main Steam Line Drain & Recirculation Sys Occurred During Leak Test.Caused by Pressure Transient in Instrument Line.Pcis Reset at 2,220 & Affected Valves Restored to Proper Position ‎ (← links)
  • 05000278/LER-1984-012-01, :on 840912,section of Standby Gas Treatment Sys Duct Work in Reactor Bldg Sump Room Collapsed.Caused by Valving Error During Transfer of Equipment Cell Exhaust. Ductwork Repaired ‎ (← links)
  • 05000278/LER-1992-001-01, :on 920103 & 04,RCIC Sys Procedure Used to Reset LP Isolation.Control Power Fuse Failed Twice When Logic Reset Depressed.Caused by Shorted Light Socket in RCIC Control Logic.Status Light & Fuses Replaced ‎ (← links)
  • 05000278/LER-1995-003-02, :on 950730,Unit 3 Scram Occurred When a Reactor Feed Pump Speed Increased.Caused by High Reactor Water Level Condition.Reset Appropriate PCIS & RPS Scram Logics ‎ (← links)
  • 05000278/LER-1991-019-02, :on 911218,power Loss to PCIS Led to Isolation of SDC Mode of RHR Sys.Caused by Relay Coil Failure.Temp Decrease Did Not Affect Activities in Progress.Blown Fuse & Relay Replaced & Preventive Maint Evaluated ‎ (← links)
  • 05000278/LER-1984-006-01, :on 840426,inconsistency in Temp Indications for Main Steam Line Tunnel Exhaust Duct Noted.Investigation Showed TE-5931A & TE-5931B Pulled Out of Exhaust Duct.Caused by Improper Scaffolding Installation ‎ (← links)
  • 05000278/LER-1984-001-02, Revised LER 84-001-02:on 840106,turbine Exhaust Rupture Diaphragm Alarm Annunicated Following Startup of HPCI Turbine.Caused by Rupture of Inner Rupture Disc.Inner Rupture Disc Replaced ‎ (← links)
  • 05000278/LER-1991-010-03, :on 910707,reactor Scram Occurred as Result of Main Generator Load Reject Trip Signal.Caused by Lightning. Scram & Isolations Reset,Sys Returned to Normal & Damaged Components Replaced ‎ (← links)
  • 05000278/LER-1984-008-01, :on 840610,three through-wall Cracks Discovered in Loop Jet Pump B Instrumentation Penetration Reducer to safe-end Weld.Caused by Igscc.Circumferential Indications on Welds Repaired ‎ (← links)
  • 05000278/LER-1984-007-01, :on 840602,HPCI Sys Made Inoperable for Maint Work W/Reactor Pressure Greater than 105 Psig.Caused by Failure of Personnel to Realize HPCI Inoperability Would Violate Tech Specs.Individual Counseled ‎ (← links)
  • 05000278/LER-1984-001, :on 840106,HPCI Turbine Exhaust Rupture Diaphragm Alarm Annunciated Following Startup.Caused by Inner Rupture Disk PSD3-23-6 Ruptured.Inner Rupture Disc Replaced ‎ (← links)
  • 05000278/LER-1984-005, :on 840209,reactor Auto Scram on High Neutron Flux Occurred Due to Runback & Subsequent Relay Failure in Main Turbine Electrohydraulic Control Sys.Caused by Faulty Relay Contact.Relay Replaced ‎ (← links)
  • 05000278/LER-1995-002-02, :on 950706,HPCI Steam Admission Valve (MO-3-23-14) Failed to Fully Open When Given Initiation Signal.Caused by Failure of Operator Motor.Operator Motor Replaced.W/Undated Ltr ‎ (← links)
  • 05000278/LER-1991-017-02, :on 910924,Automatic Depressurization Sys Discovered Inoperable Due to Components Being Unqualified. Caused by MSRV Thermal Insulation Being Improperly Installed.Subj Insulation Properly Reinstalled ‎ (← links)
  • 05000278/LER-1976-005-01, /01T:on 760111,three Snubbers on Lines RV-71A, RV-71K & RV-71H Inoperable Due to Empty Reservoirs.Caused by Leaking fittings,O-rings & Gaskets.All Defective Parts Will Be Replaced ‎ (← links)
  • 05000278/LER-1976-006-01, /01T:on 760111,snubber on Main Steam Line D Inoperable Due to Empty Reservoir.Caused by Leaking fittings,O-rings & Gaskets.All Defective Parts Will Be Replaced ‎ (← links)
  • 05000278/LER-1976-019-03, /03L:on 760117,refuel Interlocks Failed to Prevent More than One Control Rod Withdrawing.Caused by Wiring Error,Two Failed Philco Integrated Circuit Chips & Ground Wire Between Rod Position Probe & Buffer Card ‎ (← links)
  • 05000278/LER-1976-026-01, /1P:on 760226,torus Oxygen Concentration Was 5.8% While Drywell Concentration Was 4%.Cause Under Investigation.Oxygen Concentration Restored Below Tech Spec Limits & Surveillance Increased to Assure Compliance ‎ (← links)
  • 05000278/LER-1976-025-03, /03L-0:on 760224,packing Leak on RCIC Steam Isolation Valve Discovered.Caused by Valve Packing Gland Requiring Tightening Due to normal,time-related,packing Matl Compression.Packing Tightened & Sys Returned to Svc ‎ (← links)
  • 05000278/LER-1976-001-03, /03L:on 760102,outboard MSIV 86C Failed to Close. Caused by Solenoid Valve 320X-30 Seat Surface Damaged by Pipe Thread Sealing Matl.Valve Repair Kit Ordered & Will Be Installed Upon Receipt ‎ (← links)
  • 05000278/LER-1976-003-03, /03L:on 760106,main Steam Line Radiation Monitor RIS-251A Did Not Trip at Desired High Trip Setpoint.Caused by Setpoint Drift.Setpoint Adjusted to Acceptable Value ‎ (← links)
  • 05000278/LER-1976-007-01, /01T:on 760111,hydraulic Snubber on a Reactor Recirculation Pump a Inoperable Because of Empty Reservoir. Caused by Leaking fittings,O-rings & Gaskets.Defective Parts Replaced ‎ (← links)
  • 05000278/LER-1976-070-03, /03L:on 761014,main Steam Line High Flow Switch DPIS-3-2-1180 Trip Level Was 1.4% Higher than Tech Spec Limit.Caused by Setpoint Shift.Switch Recalibr & Checked for Repeatability ‎ (← links)
  • 05000278/LER-1976-027-03, /03L:on 760224,drywell Air Lock Inner Door Found to Have Unacceptable Leak.Caused by Permanent Set in Gasket Due to Normal use-related Aging.Gasket Replaced & Packing Glands on Manual Door Operator Shaft Tightened ‎ (← links)
  • 05000278/LER-1976-036-03, /03L:on 760504,recirculation Motor Generator Set 3B Tripped Due to Electrical Malfunction.Caused by Limitorque Valve Operator SMB-3 W/Serveral Broken Control Wires at Terminal Connections.Repairs Made & Valve Tested ‎ (← links)
  • 05000278/LER-1976-037-01, /01T:on 760429,high Steam Flow in HPCI Supply Line Tripped HPCI Turbine.Caused by Rapid Opening of Turbine Stop Valve.Valve Repaired & Turbine Successfully Operated ‎ (← links)
  • 05000278/LER-1976-038-03, /03L:on 760505,HPCI Turbine Exhaust Drain Pot High Level Alarm Received Indicating Valve SV 3-23-54 Had Not Auto Opened.Caused by Failure of Microswitch in Robert Shaw 83844-B1 Level Switch.Microswitch Replaced ‎ (← links)
  • 05000278/LER-1976-040-03, /03L,drywell Air Lock Inner Door Had Unacceptable Leakage.Caused by Oversize Gasket.Gasket Replaced & Tested Satisfactorily ‎ (← links)
  • 05000278/LER-1976-041-03, /03L:on 760507,APRM Channel E Found to Trip at Flux Levels Higher That License Limits.Caused by Setpoint Drift Due to Defective IN4734A Zener Diode.Diode Replaced & Channel Returned to Svc ‎ (← links)
  • 05000278/LER-1976-042-03, /03L:on 760506,HPCI Sys Became Inoperable.Caused by Misinterpretation of Surveillance Test Procedure. Procedure to Be Revised to Ensure Clarity ‎ (← links)
  • 05000278/LER-1976-045-03, /03L:on 760508,reactor Manually Scrammed at 30% Power & Rod 10-23 Failed to Fully Insert on Auto Scram Signal.Cause Not Identified.Rod Successfully Friction Tested & Considered Operable ‎ (← links)
  • 05000278/LER-1976-047-03, /03L:on 760517,torus Water Level Allowed to Drift 0.3 Ft Below Allowable Tech Spec Limit.Caused by Operator Error.Level Restored to Above Low Limit ‎ (← links)
  • 05000278/LER-1976-046-03, /03L:on 760512,main Steam Line High Temp Switch TS-5932C Failed to Trip Via Local Trip Test Pushbutton. Caused by Dirty Contacts on Circuit Board.Contacts Cleaned & Switch Tested Satisfactorily ‎ (← links)
  • 05000278/LER-1976-049-03, /03L:on 760606,refuel Floor Exhaust Vent Radiation Monitor RIS-3-17-458D Exhibited Upscale & Downscale Deflections,Causing High Radiation & Monitor Failure Alarms. Caused by Defective GE 129B2802G12 Radiation Monitor ‎ (← links)
  • 05000278/LER-1976-050-03, /03L:on 760612,APRM Rod Block F Could Not Be Obtained from Simulated High Flux Condition.Caused by Defective Relay.Relay Replaced & APRM Tested Satisfactorily ‎ (← links)
  • 05000278/LER-1976-052-03, /03L:on 760705,RCIC Speed Control Circuit Found Inoperable.Caused by Defective Voltage Dropping Assembly Resistor in Speed Control Circuit of Terry Type GS-1 Turbine.Resistor Replaced ‎ (← links)
  • 05000278/LER-1976-053-01, /01T:on 760712,main Steam Relief Valve 71B Failed Open Causing Unit to Be Shut Down.Caused by Pilot Valve Seat Leakage.Relief Valve Replaced ‎ (← links)
  • 05000278/LER-1976-054-03, /03L:on 760714,MSIV 80B Valve Closure Time Was Greater than Tech Spec Limit.Cause Undetermined.Drywell Entry Made & Valve Stroke Adjusted ‎ (← links)
  • 05000278/LER-1976-056-01, /01T:on 760720,main Steam Relief Valve 71G Failed Open.Caused by Pilot Valve Seat Leakage.Plant Shut Down & Relief Valve Replaced ‎ (← links)
  • 05000278/LER-1976-058-01, /01T:on 760722,hydraulic Shock Suppresor on Recirculation Pump B Found Inoperable.Caused by Loss of Attachment Between Suppressor & Pump.Proper Attachment Reestablished & Snubber Operability Restored ‎ (← links)
  • 05000278/LER-1976-059-01, /01T:on 760702,hydraulic Shock Suppressor on Control Rod Drive Return Line Found W/Empty Reservoir.Caused by Defective Adjusting Screw Seals.Defective Parts Replaced & Suppressor Tested for Leaks & Operability ‎ (← links)
  • 05000278/LER-1976-060-03, /03L:on 760601,no Flow Passed Through Drywell Radiation Monitoring Sys.Caused by Flow Blockage at Conoflow H-598 Pressure Control Valve.Valve Cleaned & Svc Restored ‎ (← links)
  • 05000278/LER-1976-061-01, /01T:on 760819,3 1/2-inch Crack Identified in Weld Between Torus Shell & Inner Support Column Gusset Plate. Caused by Lack of Penetration.Weld Repaired by Original Fabricator ‎ (← links)
  • 05000278/LER-1976-063-01, /01T:on 760902,individual LPCI Pump Flow Limited by Valving Approx 10,200 Gpm While 10,900 Gpm Required. Caused by Lack of Communication Between NSSS & Licensee. Correct Valve Positioning to Be Accomplished After Review ‎ (← links)
  • 05000278/LER-1976-064-03, /03L:on 760907,torus Atmosphere Sampling Inboard Automatic Isolation Valve SV-3671A Leaked Through During Local Leak Rate Test.Caused by High Seat Leakage of 1/2-inch Atkomatic Valve Co Dymo Type Solenoid Valve ‎ (← links)
  • 05000278/LER-1976-065-03, LER 76/065/03L:on 760921,isolation Valve AO-5235 Failed to Respond to Manual Close Signal.Caused by Stuck Plunger. Plunger Freed & Valve Operated Properly ‎ (← links)
  • 05000278/LER-1976-066-01, /01T:on 760921,trip Level Setting for Permissive Core Spray,Lpci Injection Valves & Recirculation Pump Discharge Valve Set at Improper Level.Caused by Lack of Communication Between NSSS & Licensee ‎ (← links)
  • 05000278/LER-1976-067-03, /03L:on 760927,condenser Low Vacuum Switch PS-3-5-11A Tripped 0.26 Inches Below Tech Spec Min.Caused by Setpoint Drift.Switch Calibr,Tested for Repeatability & Returned to Svc ‎ (← links)
  • 05000278/LER-1976-068-03, /03L:on 761005,rod Block Setting on B APRM Found 10% Higher than Tech Spec Requirement.Caused by Setpoint Drift.Trip Card Recalibr & Tested ‎ (← links)
  • 05000278/LER-1976-069-03, /03L:on 761011,core Flow Bias Input to a Logic APRM String Found 4% High.Caused by Absence of Offset Signal in GE Flow Bias Proportional Amplifier.Amplifier Removed from Svc & Signal Normalized.Failure Not Duplicable ‎ (← links)
  • 05000278/LER-1976-072-01, /01T:on 761110,surveillance Test Analysis of Weight Percentage of Sodium Pentaborate in Solution Fell Below Tech Spec Min.Caused by Normal Makeup for Sys Leakage, Water Evaporation & Test Sample Usage ‎ (← links)
  • 05000278/LER-1976-073-03, /03L:on 761110,RCIC Inboard Steam Supply Isolation Valve MO-3-13-15 Failed to Close from Handswitch During Surveillance Test.Cause Unknown.Valve Declared Inoperable & Outboard Isolation Valve Closed ‎ (← links)
  • 05000278/LER-1976-074-03, /03L:on 761123,core Spray B Full Flow Test Return Valve Failed to Close During Surveillance.Caused by Torque Switch Setting to Low.Torque Switch Setting Increased & Valve Satisfactorily Stroked ‎ (← links)
  • 05000278/LER-1977-001-01, /01T:on 770106,ultrasonic Test Indicated Crack Close to Weld 4 in Bypass Piping 4 Around Recirculation Pump Discharge Valve B.Cause Under Investigation.Section Will Be Replaced & Reexamined Prior to Return to Svc ‎ (← links)
  • 05000278/LER-1976-076-01, /01T:on 761208,drywell Oxygen Concentration Increased 0.4% Above License Limit of 4%.Caused by out-of-svc Nitrogen to Drywell Instrument.Need for Limit Adherence Will Be Stressed ‎ (← links)
  • 05000278/LER-1977-002-01, /01T:on 770110,nine Snubbers Found W/Empty Reservoirs.Grinnel Snubber Models AH1372,1373 & 1423 Experienced Seal Degradation,Resulting in Cylinder,Valve Block & Reservoir Leaks.Snubbers to Be Replaced & Tested ‎ (← links)
  • 05000278/LER-1977-003-01, /01T:on 770114,insp of Torus Support Columns Found 11 of 32 Columns Showing Visual Indications of Plate Laminations.Caused by Normal Inperfections in Rolled Steel Produced During Rolling Process.No Strengthening Necessary ‎ (← links)
  • 05000278/LER-1977-004-01, /01T:on 770121,ultrasonic Test Indicated Crack in HAZ on Reducer Side of Reducer to 12-inch Pipe Weld Near Vessel.Caused by Intergranular Stress Corrosion.Repair Will Be Made Prior to Return to Svc ‎ (← links)
  • 05000278/LER-1977-005-01, /01T:on 770128,during Insertion of Fuel Element Pb 0349,rod Inadvertently Released While Resting on Adjacent Element.Caused by Operator Elbow Bumping open-close Switch. Elements Removed & Replaced ‎ (← links)
  • 05000278/LER-1976-071-03, /03L:on 761021,during Routine Surveillance Testing,Drywell Floor Drain Inboard Isolation Valve Failed to Close.Caused by Failed Asco Solenoid Valve T8300C61RU. Solenoid Replaced ‎ (← links)
  • 05000278/LER-1983-013-03, /03L-0:on 830926,suction Valve 14-70 on Torus Dewatering Pump Declared Inoperable & Valve 14-71 Closed. Caused by Defective Thermal Overload Switch.Switch Replaced ‎ (← links)
  • 05000278/LER-1991-016-02, :on 910914,fire Watch Required by TS 3.14.D for Four 4 Kv Switchgear & Two Battery Rooms Not Performed by Fire Watch Patrol.Caused by Lack of Specificity in Clearance Control Form.Fire Watch Established ‎ (← links)
  • 05000278/LER-1991-015-02, :on 910908,core Spray Pump Found to Be Inoperable.Caused by Room Cooler Not Being Available Due to Personnel Error.No Actual Safety Consequences Occurred.Room Cooler Switch Placed in Manual Position ‎ (← links)
  • 05000278/LER-1984-002, :on 840124,reactor Heatup Rate of 111 F/H Occurred During Unit Startup.Caused by Calculation Error. Heatup Rate Reduced by Reactor Operator ‎ (← links)
  • 05000278/LER-1984-003-01, :on 840329,core Spray Logic Fuse 14A-F2B Blew During Instrument Surveillance Testing Due to Shorted Socket on Indicating Light 14A-DS26B.Shorted Socket Removed from Logic Circuit & Fuse Replaced ‎ (← links)
  • 05000278/LER-1982-016-03, /03L-0:on 820831,while Operating at Power,Loss of Position Indication Observed on Motor Operated Steam Supply Valve MO-3-13-131 to RCIC Turbine.Caused by Grounded Relay Coil.Relay & Control Fuse Replaced ‎ (← links)
  • 05000278/LER-1983-021-03, /03L-0:on 831203,moisture Monitoring Sys Indicated Moisture Alarm & Trouble Alarm at Weld 2-AHH-2 on 12-inch Recirculation Piping Loop A.Caused by Logic Board Misinterpretation of Sensor Output ‎ (← links)
  • 05000278/LER-1991-013-03, :on 910825,high Pressure Coolant Injection Sys Discovered Inoperable.Caused by Room Cooler Fan Trip on Thermal Overloads.Operator Immediately Reset Thermal Overloads ‎ (← links)
  • 05000278/LER-1983-019-03, /03L-0:on 831031,core Spray Pump Room D Cooling Fans H & G Failed to Automatically Start.Caused by Blown 6-amp Fuse within Auxiliary Control Circuitry.Fuse Replaced ‎ (← links)
  • 05000278/LER-1995-001-02, :on 950323,Unit 3 Scram on Low Condenser Vacuum Due to Loss of Steam Jet Air Ejector.Scram & PCIS Group Ii/Iii Isolation Logics Were Reset ‎ (← links)
  • 05000278/LER-1991-012-03, :on 910724,controlled Shutdown Initiated Due to Loss of auto-start Capability of Div II Core Spray Sys Concurrent W/Loss of LOCA Signal.Caused by Blown Fuse & Shorting in Light Socket.Fuse Replaced ‎ (← links)
  • 05000278/LER-1983-015-03, /03L-0:on 831013,during HPCI Sys Testing,Both HPCI Turbine Exhaust Rupture Discs Failed Due to High Pressure.Hpci Declared Inoperable.Caused by Water in Exhaust Line During Turbine Start.Disc Replaced ‎ (← links)
  • 05000278/LER-1991-011-03, :on 910710,RPS Half Scram Occurred When RPS B Motor Generator Set Outpoint Breaker Tripped During Troubleshooting.Caused by RPS M/G Set Outpoint Breaker Trip. Scram & Isolations Reset ‎ (← links)
  • 05000278/LER-1983-017-03, /03L-0:on 831020,during post-refueling Outage Startup,W/Unit at Low Power,Offgas Radiation Monitoring Sys Found Inoperable.Caused by Condensation in Offgas Sample Lines.Water Withdrawn from Sample Lines ‎ (← links)
  • 05000278/LER-1983-016-03, /03L-0:on 831017,during Startup,Moisture Sensor in Moisture Monitoring Sys Failed.Caused by Defective Techmark Ltd Sensor.Sensor Will Be Replaced ‎ (← links)
  • 05000278/LER-1983-014-03, /03L-0:on 831004,while Shutdown W/Reactor Mode Switch in Refuel Position,Second Control Rod Could Be Selected When Control Rod 02-35 Selected.Caused by Open Diode on GE Relay Card.Diode Replaced ‎ (← links)
  • 05000278/LER-1984-004, :on 840125,reactor Coolant Temp Dropped Below 120 F When Feedwater Inadvertently Pumped Into Reactor Vessel.Caused by Operator Error.Level Restored to Normal & Main Steam Line Drains Opened ‎ (← links)
  • 05000278/LER-1983-022-03, /03L-0:on 831207,4 Kv Emergency Bus Undervoltage Relay IVA-127 Failed to Operate.Caused by Binding of Relay Rotating Disk Due to Dust Buildup.Relays Cleaned,Tested & Returned to Svc ‎ (← links)
  • 05000278/LER-1983-023-03, /03L-0:on 831213,while Performing Routine Surveillance Test,Torus narrow-range Level Indicator Found Out of Calibr.Level Indicator Replaced,Calibr & Returned to Svc on 831216 ‎ (← links)
  • 05000278/LER-1983-020-03, /03L-0:on 831123,discovered RCIC Turbine Steam Supply Low Pressure Isolation Switch Out of Calibr.Caused by Setpoint Drift.Instrument Recalibr & Returned to Svc ‎ (← links)
  • 05000278/LER-1983-024-03, /03L-0:on 831219,moisture Sensor in Moisture Monitoring Sys Failed.Caused by Defective Techmark Limited Sensor.Inoperable Sensor Will Be Replaced During Next Scheduled or Forced Outage ‎ (← links)
  • 05000278/LER-1983-011-01, /01T-0:on 830407,loss of Control Rod Position Indication Occurred from Control Rods 22-47,58-31 & 54-15. Caused by Improper Use of Jumper Procedure on 830311,26 & 0402.Jumpers Removed.Jumper Procedure Suspended ‎ (← links)
  • 05000278/LER-1991-014-03, :on 910905,HPCI Sys Discovered Inoperable When HPCI Flow Control Loop Power Supply Inverter Inadvertently Turned Off by Installation Workers (non-util;non-licensed). Inverter Will Be Relocated ‎ (← links)
  • 05000278/LER-1991-009-03, :on 910530,standby Liquid Control Sys Declared Inoperable.Caused by Reactor Operator Incorrectly Selecting Procedure Used to Initially Fill & Setup Sys.Individuals Involved Coached ‎ (← links)
  • 05000278/LER-1991-008-03, :on 910520,RHR Pump 3C Unexpectedly Started During RHR B Channel Logic Sys Functional Test.Caused by Personnel Error.Sys Secured & Surveillance Test Completed Satisfactorily ‎ (← links)
  • 05000278/LER-1983-009-01, /01T-0:on 830908,during Surveillance Testing W/One Diesel Generator Inoperable,Breaker Between Diesel Generator E-1 & Emergency Bus E-13 Failed to Close Manually.Cause Unknown.Breaker Tested Successfully ‎ (← links)
  • 05000278/LER-1994-005-03, :on 941011,Unit 3 Scram Occurred Due to Static Inverter Failure.Appropriate PCIS & RPS Scram Logic Reset & Affected Sys Reset to Appropriate Configuration & Failed Unit 3 Transformer Replaced & Properly Setup ‎ (← links)
  • 05000278/LER-1994-004-02, :on 940924,HPIS Inoperable When Steam Supply Valve Was Closed to Isolate Leak.Caused by Packing Leak on MO-3-23-15.Corrective Actions Being Developed.W/Undated Ltr ‎ (← links)
  • 05000278/LER-1983-012-01, /01T-0:on 830425,during Refueling Outage,While Performing Nde,Intergranular Stress Corrosion Cracking Indications Found in Heat Affected Zone of 12 Welds.Caused by Stress Corrosion.Weld Insp Increased ‎ (← links)
  • 05000278/LER-1991-006-03, :on 910410,Tech Spec Violation Occurred When Darm Had Been Isolated.Cause Unknown.Manual Sample/Purge Valve Placed in Sample Position on 910410 & Drywell Atmospheric Radiation Levels Verified ‎ (← links)
  • 05000278/LER-1991-005-03, :on 910410,HPCI Sys Declared Inoperable Due to High Water Level in Turbine Exhaust Line.Caused by Vacuum Relief Valves Failure to Prevent Siphoning of Torus Water. Maint Procedures Which Inspect HPCI Revised ‎ (← links)
  • 05000278/LER-1983-005-01, /01T-0:on 830312,refueling Bridge Interlock Inoperable.Caused by out-of-adjustment Interlock Switch. Switch Adjusted ‎ (← links)
  • 05000278/LER-1994-003-03, :on 940811,HPCI System Was Considered Inoperable & Was Placed in Secured Condition by Reactor Operator.Caused by Individuals Incorrectly Deciding to Work on CR Relay.Hpci System Was Restored ‎ (← links)
  • 05000278/LER-1983-010-03, /03L-0:on 830222,during Refueling Outage,Testing of Recently Installed Fire Detection Sys Mod Revealed Previously Undetected Wiring Errors Between Two Sets of Two Annunciator Circuits.Caused by Wiring Error ‎ (← links)
  • 05000278/LER-1982-026-03, HPCI Sys Declared Inoperable to Investigate Delayed Opening of Turbine Stop Valve Upon Sys Initiation.Caused by Failure of Corroded Steam Trap to Drain Inlet Steam Line.Trap Rebuilt ‎ (← links)
  • 05000278/LER-1982-018-03, /03L-0:on 820924,torus Narrow Range Level Recorder Indicated Erratically.Investigation Determined Torus Water Level within Tech Spec.Caused by Const Personnel Knocking Instrument Out of Calibr.Personnel Counseled ‎ (← links)
  • 05000278/LER-1982-020-03, /03L-0:on 821006,during Surveillance Test,Hpci Room Carbon Dioxide Fire Protection Sys Failed to Inject Automatically.Caused by Dirty Contacts on electro-manual Pilot Control Solenoid Valve.Contacts Cleaned ‎ (← links)
  • 05000278/LER-1983-003-03, /03L-0:on 830127,HEA Relay on Emergency Safeguard Bus E23 Tripped Normal Supply & Locked Out Backup & Diesel Supplies.Caused by Operation of Relay on Bus E23.Activating Devices May Be Defective & Will Be Bench Tested ‎ (← links)
  • 05000278/LER-1983-008-01, /01T-0:on 830214,inboard Main Steam Drain Valve MO-2-74 & Inboard MSIVs 80:A,C & D Failed to Meet Tech Spec Leak Test Limits.Cause Not Known.Failed Valves Scheduled for maint.Thirty-day Followup Rept to Be Submitted After Ma ‎ (← links)
  • 05000278/LER-1982-023-03, /03L-0:on 821209,during Surveillance Testing,Two HPCI Turbine Exhaust Rupture Discs Failed.Caused by High Back Pressure from Water in Exhaust Line.Water Pulled from Torus Due to Faulty Vacuum Breakers ‎ (← links)
  • 05000278/LER-1982-024-03, /03L-0:on 821209,fire Alarm Received from Core Spray Pump Rooms B & D & RHR Pump Room C.Caused by Reversed Wiring in B & D Core Spray & RHR Pump Room C.Wiring Corrected ‎ (← links)
  • 05000278/LER-1991-003-02, :on 910225,high Pressure Coolant Injection Sys Inoperable.Caused by Inadequate Procedure.Weekly Surveillance Revised & New Design to Replace Existing Tappet Assembly ‎ (← links)
  • 05000278/LER-1982-025-03, /03L-0:on 821214 & 18,torus Normal Range Level Recorder Not Responding to Changes in Level.Caused by off-centered Displacer to Force Arm Connection in Level Transmitter.Arm Centered ‎ (← links)
  • 05000278/LER-1993-007, :on 930820,identified That Stated Surveillance Test Not Performed Prior to Exceeding TS Out of Surveillance Date,Resulting in Violation on 930808.Caused by Inadequate Review.Personnel to Be Counselled ‎ (← links)
  • 05000278/LER-1994-002-01, :on 940203,discovered Main Generator Ground Relay Status Light Out.Caused by Internal Rack Out Tab Not Installed on Alterex Field Breaker.Damaged Component Repaired & Breaker Replaced W/Spare ‎ (← links)
  • 05000278/LER-1994-001, :on 940124,HPCI Sys Declared Inoperable During Performance of Quarterly Surveillance Test.Caused by Leak on HPCI Sys Hydraulic Control Line.Hydraulic Control Line Repaired & HPCI Sys Tested ‎ (← links)
  • 05000278/LER-1991-002-01, :on 910121,hourly Fire Watch Patrol for RHR B Fire Damper Not Performed.Caused by Lead Protection Technician Closing Out Wrong Fire Watch Patrol.Effective Means of Communication Established ‎ (← links)
  • 05000278/LER-1991-001-02, :on 910116,reactor Scram Occurred Due to Turbine Control Valve Fast Closure on Main Generator Load Reject Signal Because of Main Transformer Sudden Pressure Lookout Signal.Caused by Component Failure ‎ (← links)
  • 05000278/LER-1990-016-03, :on 901202,main Steam Relief Valve 71J Opened for Approx 3/4 Due to Installation of Jumper in Wrong Panel.Caused by Inadequate pre-job Briefing.Technicians Counseled & Procedures Will Be Revised ‎ (← links)
  • 05000278/LER-1990-015-03, :on 901125,operators Failed to Record Drywell Sump Flow Readings Every 4 H Per Tech Spec 3.6.C.Caused by Personnel Error.Timer Will Be Obtained to Alarm Every 4 H to Prompt Operator to Record Drywell Readings ‎ (← links)
  • 05000278/LER-1989-012-01, :on 891222,determination Made That Potential Existed for Loss of Reactor Coolant Inventory Beyond Makeup Capability of RCIC Sys Relied Upon in Fire Protection Program Analysis for Fire in Fire Area 13N ‎ (← links)
  • 05000278/LER-1990-014-03, :on 901103,unexpected ESF Actuation of Primary Containment Isolation Sys Occurred Due to Personnel Error ‎ (← links)
  • 05000278/LER-1982-015-03, /03L-0:on 820822,drywell Pressure Recorder PR5805 Failed Downscale.Caused by Blown Fuse.Fuse Replaced & Sys Operation Verified ‎ (← links)
  • 05000278/LER-1990-013-03, :on 901009,core Spray Pump Actuation Occurred During Testing Due to Personnel Error ‎ (← links)
  • 05000278/LER-1983-004-03, /03L-0:on 830127,during Power Operation,Torus Purge Air Supply AO-3521-B Did Not Fully Close Upon Completion of Deinerting Operations.Caused by Piece of Plastic Falling Through Pipe Chase.Plastic Removed ‎ (← links)
  • 05000278/LER-1983-002-01, /01T-0:on 830126,during Local Leak Rate Testing of HPCI Breaker Isolation Valve,Valve Did Not Fully Close & HPCI Declared Inoperable.Caused by Solidified Grease in Operator Gear Train.Operator Cleaned & Successfully Tested ‎ (← links)
  • 05000278/LER-1983-006-01, /01T-0:on 830131,during Local Leak Rate Testing of B Containment Atmosphere Dilution Nitrogen Injection Penetration,Determined Valve Leaking Excessively.Caused by Scored Seat & Foreign Matl.Bonnet,Stem & Plug Replaced ‎ (← links)
  • 05000278/LER-1982-012-03, /03L-0:on 820806,at Normal Power,Reactor Bldg 3A Exhaust Radiation Monitor Experienced Downscale Failure. Caused by Failure of Geiger-Mueller Tube (GE Part 194x 927G011) Detector.Tube Replaced & Unit Calibr ‎ (← links)
  • 05000278/LER-1979-036-03, /03L-0:on 791105,leak Rates Exceeded Tech Spec Limits.Caused by Debris Blocking Valve Closure.Sealing Surfaces Cleaned & Polished.Valves Retested & Returned to Svc ‎ (← links)
  • 05000278/LER-1979-014, /O3L-0 on 790522:offsite Source Breaker SU25 Tripped on Low Air Pressure.Caused by Short Circuit in Light Socket & Dirty Contacts on Voltage Relay.Relay Contacts Cleaned & Socket Removed Pending Replacement ‎ (← links)
  • 05000278/LER-1979-015, /O3L-0 on 790523:automatic Depressurization Sys a Auto Blowdown Timer Trip Setting Found 13-s Less than Tech Spec Min.Caused by Setpoint Drift of Time Delay Relay.Relay Readjusted,Tested & Returned to Svc ‎ (← links)
  • 05000278/LER-1979-005-03, /03L-0 on 790208:setpoint of Reactor Core Isolation Cooling Turbine Steam Supply Flow Sensor Was Above Tech Specs Max.Caused by Setpoint Drift on Barton Model 288 Differential Pressure Switch.Switch Recalibrated ‎ (← links)
  • 05000278/LER-1978-023-03, /03L-0 on 781127:D Reactor Bldg Area Exhaust Radiat Monitor Indicated Downscale & Was Determined to Be Inoperable.Caused by Defective Zener Diode in Amplifier of GE sensor-converter Unit,Model 194X927011 ‎ (← links)
  • 05000278/LER-1978-021-01, /01T-0 on 781106:while at Pwr Feedwater Control Sys Failure Resulted in Reactor Low Level Transient & Scram HPCI Initiated But Delivered Unstable Flow & Soon Tripped on Overspeed.Cause Was HPCI Governor Being Out of Calibr ‎ (← links)
  • 05000278/LER-1978-021, Forwards LER 78-021/01T-0 ‎ (← links)
  • 05000278/LER-1978-019-01, /01T-0:on 780929,quantity of Activity in Purge Stream of Offgas Sample Underestimated,Resulting in Three Peaks Exceeding Tech Specs.Purging of Offgas Directly Into Vent Sys During Offgas Process Halted ‎ (← links)
  • 05000278/LER-1978-016-03, /03L-0 on 780904:during Surveillance Test Unit 3 Dmain Steam Radiat Monitor Failed to Cause a Half Scram Due to Defective Transistor.Transitor Was Replaced & Monitor Returned to Svc in 6 Hours ‎ (← links)
  • 05000278/LER-1990-010-03, :on 900804,HPCI Declared Inoperable Due to Failure of Manual & Overspeed Trip Tappet Assembly.Caused by Design Problem Re Tappet Swelling.New Design Being Provided by GE Will Replace Tappet Assembly ‎ (← links)
  • 05000278/LER-1982-017-03, /03L-0:on 820902,during Heavy Rainstorm,Operator Observed That Vent Stack Flow Recorder Indicated Downscale on Both Channels.Caused by Pilot Tubes Filling W/Water During Severe Storm.Indication Returned When Storm Subsided ‎ (← links)
  • 05000278/LER-1993-011-02, :on 931211,terminal Block in Bottom of 4 Kv Cubicle Knocked Off Its Mount.Caused by Improper Coordination of Required TS Surveillance Requirement Shift Supervisor.Supervisor Counselled ‎ (← links)
  • 05000278/LER-1993-010-03, :on 931201,TS Required Shutdown Initiated Due to Failed Residual Heat Removal Sys Valve.Caused by Bent Valve Stem on MO-3-10-025A.RHR Loop Injection Valve Was Dissassembled & New Valve Stem Installed ‎ (← links)
  • 05000278/LER-1980-029-03, /03L-0:on 801209,main Steam Line Radiation Monitor C Indicated Reduced Background Reading W/Trip Setpoint Greater than Tech Spec.Caused by Instrument Zero Drift. Monitor Recalibr ‎ (← links)
  • 05000278/LER-1980-026-01, /01T-0:on 801114,HPCI Flow Controller Showed Downscale Output.Hcpi Declared Inoperable.Caused by Failed Zener Diode & Resistor Resulting in Output Drift.Parts Replaced ‎ (← links)
  • 05000278/LER-1980-021-03, /03L-0:on 800818,during PCIS Logic Sys Functional Testing W/Plant Shutdown,Primary Containment Ventilation Valve AO-3506 Failed to Close.Caused by Asco Model S56756 Solenoid Valve Stuck in Energized Position.Valve Cleaned ‎ (← links)
  • 05000278/LER-1980-019-03, /03L-0:on 800806,while Performing Surveillance Test on RHR Sys W/Unit at power,MO-3-10-25A LPCI Injection Valve Failed to Open.Caused by Multiple Full Penetration Cracks on Drive Sleeve of Type SMB-4 Limitorque Operator ‎ (← links)
  • 05000278/LER-1990-011-03, :on 900910,HPCI Sys Inoperable Due to Dirty Relay Contact in Auxiliary Oil Pump Motor Starter ‎ (← links)
  • 05000278/LER-1990-012-03, :on 891120,miscalibration of Reactor Level Transmitters Resulted in Tech Spec Violation ‎ (← links)
  • 05000278/LER-1993-008-03, :on 931018,identified That Two of Eleven MSRVs & One of Two SVs Did Not Lift within TS Plus or Minus 1% Tolerence Due to Small Drift in Setpoint of Valves.Ts Change Request Being Evaluated ‎ (← links)
  • 05000278/LER-1990-009-03, :on 900727,discovered That Recirculation Loop Temp Increased in Excess of Allowable Heat Up Rate & Temp Reading Not Recorded at Required Intervals.Caused by Personnel Error & Procedural Deficiency ‎ (← links)
  • 05000278/LER-1990-008-02, :on 900727,offgas Recombiner Isolation Occurred Causing Main Condenser Vacuum to Begin Decreasing.Caused by Component/Sys Failure in Offgas Recombiner Condensate Sys. Design of Sys Will Be Evaluated for Root Cause ‎ (← links)
  • 05000278/LER-1993-009-03, :on 931113,HPCI Sys Declared Inoperable When Discharge Valve Would Not Open Due to Misaligned Relay Contact.Following Relay adjustment,MO-3-23-19 Tested Satisfactorily & Associated TS LCO Exited ‎ (← links)
  • 05000278/LER-1993-006-02, :on 930814,LPCI Sys Became Inoperable When Triple Low Water Level Signal Simulated on Unit 2.RWL Instrumentation LT-72B Valved Out of Svc & Equalized Allowing Indicated Water Level to Increase ‎ (← links)
  • 05000278/LER-1993-005-02, :on 930809,HPCI Sys Declared Inoperable Due to Defective Flow Controller.Flow Controller Removed,All Potentiometers & Boards Cleaned,Flow Controller Reinstalled & Necessary Testing & Tuning Performed ‎ (← links)
  • 05000278/LER-1993-004-03, :on 930730,simulated Low Steam Flow Signal to Recombiner Initiated Isolation Signal to Off Gas Recombiner, Causing Main Condenser Vacuum to Begin Decreasing.Special Procedure SP-1438 Revised ‎ (← links)
  • 05000278/LER-1990-007-03, :on 900620,RWCU Isolated While Pressurizing Sys Following Isolation Valve Insp.Caused by Design Weakness. Design of Instrumentation Reviewed & Procedural Controls Enhanced ‎ (← links)
  • 05000278/LER-1982-011-03, /03L-0:on 820620,fuse on Positive Leg to Transmitter Circuit Board Blew Causing Downscale Failure of Drywell 0-70 Psig Pressure Recorder.Caused by Intentional Ground Installed on Positive of Transmitter.Fuse Replaced ‎ (← links)
  • 05000278/LER-1982-010-03, /03L-0:on 820618,downscale Failure of Drywell 0-70 Psig Pressure Recorder Occurred.Caused by Blown 0.3 Ampere Fuse Installed on Positive Side of Power Supply to Transmitter Circuit Board.Fuse Replaced ‎ (← links)
  • 05000278/LER-1982-009-03, /03L-0:on 820530,operator Lost Valve Indication Position on HPCI Sys.Caused by Blown Fuse in Instrument Panel Due to Shortened Solenoid Coil in Turbine Exhaust Drain Valve.Fuse Replaced & Valves Stroked ‎ (← links)
  • 05000278/LER-1982-007-03, /03L-0:on 820519,during Operability Testing,Hpci Steam Inlet valve,MO-14,blew Fuses When Stroked & Turbine Stop valve,HO-5513,failed to Close in Response to Remote Trip Signal.Steam Inlet Valve Repacked & Switch Replaced ‎ (← links)
  • 05000278/LER-1982-005-03, /03L-0:on 820514,during Normal Operation,Reactor Operator Heard Relay in Primary Containment Isolation Sys Energize.Caused by Defective Component in Rosemount Model 510DU Slave Trip Unit.Instrument Replaced ‎ (← links)
  • 05000278/LER-1982-006-01, /01T-0:on 820504,GE Notified Util That Odyn Pressurization Event MCPR Values May Be Nonconservative. Caused by Nonconservative Value of Active Fuel Length Used in Reload 4 Odyn Transient Analysis ‎ (← links)
  • 05000278/LER-1982-006, Forwards LER 82-006/01T-0.Detailed Event Analysis Submitted ‎ (← links)
  • 05000278/LER-1982-003-03, /03L-0:on 820413,core Spray Pump C Failed to Start Following Breaker Racking on 820329 for Valve Maint.Caused by Misaligned Pump Breaker Cell Switch.Breaker Reracked & Operator Counseled ‎ (← links)
  • 05000278/LER-1982-004-03, /03L-0:on 820410,while Performing Surveillance Tests on D Core Spray & D RHR Pumps,Room Cooler Fans Failed to Start W/Control Switches in Auto or Run Position.Caused by de-energized Control Circuit.Circuit re-energized ‎ (← links)
  • 05000278/LER-1982-002-03, /03L-0:on 820331,during Maint Outage,Hydraulic snubbers,1-GG-S-30,1-GG-S-34 & 23-HBS-2A Found to Have Empty Reservoirs.Caused by Deterioration of Lynair 2.5-inch Hydraulic Seals.Seals Replaced & Snubbers Rebuilt ‎ (← links)
  • 05000278/LER-1990-006-03, :on 900511,blown Fuse from Battery Charger 3B Resulted in Declaring HPCI Sys,Core Spray B Logic,Rhr B Logic,Core Spray Subsystem B,Rhr Subsystem B & E2 & E4 Emergency Diesel Generators Inoperable ‎ (← links)
  • 05000278/LER-1990-005-03, :on 900507,Group 2A Primary Containment Isolation Sys Isolation Occurred During Surveillance Test. Caused by Inadequate Worker Practices.Blown Fuse Replaced & Personnel Counseled ‎ (← links)
  • 05000278/LER-1990-004-03, :on 900430,Tech Spec Violation Occurred When MSIV Closure Timing Testing Not Performed in Required Surveillance Interval.Caused by Ambiguous Test Procedure. Surveillance Test Revised ‎ (← links)
  • 05000278/LER-1990-002, :on 900128,ESF Sys Actuations Occurred Due to Reactor Vessel Level Fluctuations After Manual Scram.Caused by Failure of O-ring on Fluid Inlet Port to Servo Valve for Hydraulically Operated Valve.Valve Replaced ‎ (← links)
  • 05000278/LER-1982-001-03, /03L-0:on 820105,during Surveillance Testing W/ Unit at Full Power,Main Steam Line Low Pressure Switch Found Below Min Tech Specs Setting of 850 Psig by 1.3% of Scale. Caused by Setpoint Drift of Barksdale Model B2T12SS Swit ‎ (← links)
  • 05000278/LER-1981-022-03, /03L-0:on 811221,during Surveillance Testing, Torus High Level Switches 3-23-91-A & B Determined to Be Out of Calibr by 1/2 Inch.Instruments Are Robertshaw Type 83035-A2.Caused by Setpoint Drift.Instruments Recalibr ‎ (← links)
  • 05000278/LER-1981-021-03, /03L-0:on 811211,D Core Spray Pump Failed to Start During Surveillance Test Due to Failure of Pump Breaker to Close.Cause Not Determined.Failed Breaker Replaced & Checked Daily for 2 Wks to Verify Core Spray Sys Operability ‎ (← links)
  • 05000278/LER-1981-019-03, /03X-1:on 811121,drywell Wide Range Pressure Recorder PR-3508 Did Not Receive Signal & Was Declared Inoperable.Caused by Intentional Internal Ground in Printed Circuit Assembly.Floating Dc Sys Substituted ‎ (← links)
  • 05000278/LER-1981-020-03, /03L-0:on 811207,reactor Coolant Isolation Cooling Torus Suction Valve MO-3-13-41 Failed to Stroke.Caused by Broken Indicating Rod Jammed within Guide Cap.Broken Rod Removed & Valve Successfully Stroked Electrically ‎ (← links)
  • 05000278/LER-1981-018-03, /03L-0:on 811124,HPCI Turbine Steam Supply Valve MO-3-123-14 Failed Shut & Sys Declared Inoperable.Caused by Blown Fuse in Valve Motor Circuit.Fuse Replaced ‎ (← links)
  • 05000278/LER-1981-012-03, /03L-0:on 810428,snubber from a Recirculation Pump Discharge Header Found to Have Locking Velocity Under Compression Less than Acceptable Value.Cause Not Determined. Snubber to Be Recalibr ‎ (← links)
  • 05000278/LER-1981-017-03, /03L-0:on 811109,reactor Core Isolation Cooling High Steam Flow Isolation Switch Exceeded Tech Spec Limit. Caused by Setpoint Drift of Barton Model 288 Dpis.Instrument Recalibr ‎ (← links)
  • 05000278/LER-1981-015-01, /01X-1:on 811023,offgas Sampling Sys Found Not Receiving Sufficient Flow.Caused by Sample Line Root Valve That Had Been Closed During Welding.Valve Opened & Added to Sys Checkoff List ‎ (← links)
  • 05000278/LER-1981-016-03, /03L-0:on 811027,during Surveillance Testing,Speed Control Problems W/Reactor Core Isolation Cooling Sys Were Observed.Caused by Electronic & Hydraulic Speed Controls Being Out of Tolerance.Adjustments Made to Components ‎ (← links)
  • 05000278/LER-1981-009-03, /03L-0:on 810216,during Surveillance Test,Oil Leak of 3-5 Gpm Found on Oil Supply Line to HPCI Turbine Manual/ Overspeed Trip Mechanism.Caused by Ruptured Diaphragm in Oil Line Pressure Control Valve VC-210 ‎ (← links)
  • 05000278/LER-1981-002-03, /03L-0:on 810109,HPCI Turbine Exhaust Inboard Drain Isolation Valve AO-5247 Failed to Stroke Fully.Caused by Cocked Valve Packing Follower Preventing Free Valve Stem Travel.Follower Realigned & Packing Retensioned ‎ (← links)
  • 05000278/LER-1981-001-01, /01P-0:on 810101, While Operating at 100% Power, During Surveillance Testing,Core Spray Pump D Was Found Nonoperable.Caused by de-energized Condition of Springs in 4 Kv Circuit Breaker.Breaker Replaced ‎ (← links)
  • 05000278/LER-1993-003-03, :on 930310,discovered That Reactor Vessel Head Vents Closed & pressure-temp Data Not Obtained.Caused by Operator Not Fully Moving Control Switches to Auto Position. Head Vents Restored to Proper Position ‎ (← links)
  • 05000278/LER-1993-002-03, :on 930307,automatic Scram on Reactor Water Level When Reactor Feed Pump Feed Tripped on High Vibrations.Evaluation Will Be Performed on Defective Controller to Identify C/As Necessary ‎ (← links)
  • 05000278/LER-1993-001-03, :on 930125,HPCI Sys Declared Inoperable When Discharge Valve Failed to Open.Caused by Misaligned Relay Contact.Relay Adjusted & Tested Satisfactorily.Evaluation Underway ‎ (← links)
  • 05000278/LER-1981-015, Forwards LER 81-015/01T-1.Detailed Event Analysis Submitted ‎ (← links)
  • 05000278/LER-1981-013-01, /01T-0:on 810830,personnel Discovered Water Backed Up Out of Floor Drain Sys Flowing Under Railroad Doors. Caused by Blockage in Drain Sys.Blockage Cleared,Water Pumped Out & Processed Through Radwaste ‎ (← links)
  • 05000278/LER-1981-013, Forwards LER 81-013/01T-0.Detailed Event Analysis Submitted ‎ (← links)
  • 05000278/LER-1983-001-03, /03L-0:on 830103,setpoint of Main Steam Line Low Pressure Switch a (PS-3-2-134A) Found Approx 33% Below Min Tech Spec Limit.Caused by Setpoint Drift of Barksdate Model B2T12SS Pressure Switch.Instrument Recalibr ‎ (← links)
  • 05000278/LER-1982-027-03, /03L-0:on 821227,RCIC Turbine Throttle Valve Tripped Closed Due to Pump Overspeed.Caused by Closed Suction Valve Following Valve Stroking Section of Surveillance Test.Valve Opened & Tested Successfully ‎ (← links)
  • 05000278/LER-1982-021-01, /01T-0:on 821101,during Source check,3A Reactor Vent Stack Radiation Monitor Determined Insensitive.Caused by Drift in Instrument Voltage Plateau.Instrument Realigned & Returned to Svc on 821102 ‎ (← links)
  • 05000278/LER-1982-022-01, /01P:on 821104,determined 3D RHR HX Leaked Slightly Radioactive Water Into Intake Structure Via High Pressure Svc Water Piping During 821025-1102.Sys Isolated & HX Drain Valve Opened ‎ (← links)
  • 05000278/LER-1982-021, Revised LER 82-021/01P:on 821101,3A Reactor Bldg Vent Stack Radiation Monitor Found to Have Less than Desired Sensitivity.Caused by Drift in Channel Voltage Plateau. Monitor Calibr & Returned to Svc ‎ (← links)
  • 05000278/LER-1982-019-03, /03L-0:on 820928,floor Cable Penetration Found W/ 1.5-square-inch Gap Due to Broken Marinite Barrier Board. Probably Caused by Impact to Kick Plate Encompassing Cable Tray Penetration.Board Repaired ‎ (← links)
  • 05000278/LER-1982-013-03, /03L-0:on 820807,torus Narrow Range Level Indicator Failed Downscale.Caused by Failure of Linkage on Foxboro Level Transmitter.Linkage Replaced & Transmitter Recalibr ‎ (← links)
  • 05000278/LER-1982-014-03, /03L-0:on 820811,loss of Channels 1 & 2 Required for Indication of Drywell Temp Occured During Surveillance Testing.Caused by Failed Detector Cards Due to Defective Power Supply for Indicator.Power Supply & Cards Replaced ‎ (← links)
  • 05000278/LER-1991-004-02, :on 910324,reactor Operator Failed to Initial Surveillance Test 5.3, Inoperable Valve Position Daily Log. Caused by Personnel Error Due to Failure to Follow Procedure.Operator Counselled ‎ (← links)
  • 05000278/LER-1990-001-03, :on 900108,HPCI Sys Declared Inoperable During Surveillance Testing When Start Time Exceeded 25 S.Caused by Inadequate Calibr Procedure Which Allowed Setting of 18 S. Ramp Generator & Signal Converter Replaced ‎ (← links)
  • 05000278/LER-1990-002-02, :on 900128,reactor Manually Scrammed Due to Leak of Electrohydraulic Control Sys Fluid.Caused by Lock Nut on Interlock Dump Valve Setting Adjustment Bolt Becoming Unsecured Due to Sys Vibration.Leak Stopped ‎ (← links)
  • 05000278/LER-1981-014-01, /01T-0:on 810928,while in Cold Shutdown Condition W/Crd Sys Off to Support Plant Testing,Problems Were Encountered in Maintaining Vessel Level.Caused by Personnel Error & Incomplete Closure of Feedwater Stop Valve ‎ (← links)
  • 05000278/LER-1981-014, Forwards LER 81-014/01T-0.Detailed Event Analysis Submitted ‎ (← links)
  • 05000278/LER-1989-009-03, :on 891207,HPCI Sys Declared Inoperable When Sys Failed to Start During Pump,Valve & Flow Surveillance Test.Caused by Loose Lock Nut on HPCI Oil Sys Relief Valve. Lead Seal Wire to Be Placed on Valve Caps ‎ (← links)
  • 05000278/LER-1981-004-03, /03L-0:on 810126,reactor Pressure Switch PS-3-2-3-102C,which Trips Recirculation Pump a Found to Exceed Tech Spec Limit.Caused by Setpoint Drift of Static-O-Ring Pressure Switch.Instrument Recalibr ‎ (← links)
  • 05000278/LER-1981-005-03, /03L-0:on 810127,setpoint of Temp Switch TS 5943 B (HPCI Steam Line Area High Temp Isolation) Found to Be Above Tech Spec Limit.Caused by Setpoint Drift.Instrument Recalibr to within Tech Spec Limits,Tested & Returned to Svc ‎ (← links)
  • 05000278/LER-1981-003-01, /01T-0:on 810113,during Surveillance Test W/Unit at Full Power,Oil Leak of Approx 3-5 Gallons Per Minute Discovered on Oil Supply Line to HPCI Turbine Manual/ Overspeed Trip Mechanism.Caused by Ruptured Diaphragm ‎ (← links)
  • 05000278/LER-1981-003, Forwards LER 81-003/01T-0 ‎ (← links)
  • 05000278/LER-1980-030-03, /03L-0:on 801214,backup Nitrogen Bottle Supply to Inboard Containment Isolation Valve AO-3506 Found Valved Out of Svc.Pressure Regulation Adjustment Screw Missing.Cause Unknown.Backup Nitrogen Supply Restored ‎ (← links)
  • 05000278/LER-1989-010-03, :on 891211,monthly Surveillance Test ST 9.7 Not Performed within Surveillance Interval Established by Tech Spec Table 4.1.1.Caused by Combination of Programmatic Weaknesses.Review Performed ‎ (← links)
  • 05000278/LER-1989-011-03, :on 891213,discovered That Two Surveillance Tests of Turbine Stop & Control Valve Encl Not Performed Per Tech Specs.Caused by Incorrect Std Practice of Surveillance Testing.Programmatic Controls Established ‎ (← links)
  • 05000278/LER-2019-001, Failure of Reactor Mode Switch Results in Condition Prohibited by Technical Specifications ‎ (← links)
  • 05000278/LER-1981-008-01, /01T-0:on 810211,main Isolation Valve on Loop B Mistakenly Isolated Instead of Loop a Valve During Installation of Test Connection to 1-inch Containment Atmospheric Dilution Line.Caused by Wrong Valve Designation ‎ (← links)
  • 05000278/LER-1981-008, Forwards LER 81-008/01T-0 ‎ (← links)
  • 05000278/LER-1980-027-01, /01T-0:on 801124,HPCI Valve MO-3-23-14 Kept Driving in Closed Direction Causing Valve Fuses to Blow. Probably Caused by Improper Adjustment of Valve Closing Torque Switch.Valve Disassembled,Inspected & Tested ‎ (← links)
  • 05000278/LER-1980-027, Forwards LER 80-027/01T-0 ‎ (← links)
  • 05000278/LER-1980-018-03, /03L-0:on 800802,during Surveillance Test on PCIS Normally Open Valves W/Unit at Full Power,Reactor Water Cleanup Sys Return Isolation Valve MO-3-12-68 Failed to Close Using Control Switch.Cause Not Determined ‎ (← links)
  • 05000278/LER-1980-017-03, /03L-0:on 800802,during Surveillance Test on PCIS Normally Open Valves,Drywell 2-inch Valve AO-3509 Failed to Close.Caused by Tight Packing on Valve.Packing & Proper Operation Verified ‎ (← links)
  • 05000278/LER-1980-031-03, /03L-0:on 801218,reactor Core Isolation Cooling Inboard Steam Supply Isolation Valve Did Not Automatically Close.Caused by Valve Closing Torque Switch on Type Smb Limitorque Operator for Valve MO3-13-15 Being Open ‎ (← links)
  • 05000278/LER-1980-028-01, /01T-0:on 801203,HPCI Steam Supply Valve, MO-3-23-14,failed to Fully Close.Caused by HPCI Sys Being Inoperable for Valve Insp.Valve Reassembled & Tested ‎ (← links)
  • 05000278/LER-1980-028, Forwards LER 80-028/01T-0 ‎ (← links)
  • 05000278/LER-1980-024-03, /03X-1:on 800911,flow Through Primary Containment Gas Sampler Stopped.Caused by Open Circuit in Sample Exhaust Pump Local Control Switch.Switch Replaced ‎ (← links)
  • 05000278/LER-1980-025-03, /03L-0:on 800917,indication for SV-3978A - G Control Switches Was Lost.Caused by Short in Coil of Dymo Type Solenoid Valve Which Blew Common Fuse in Control Circuit for All Sevel Valves.Fuse Replaced ‎ (← links)
  • 05000278/LER-1980-023-03, /03L-0:on 800908,reactor Water Cleanup Demineralizer Water Inlet Temp Switch Did Not Actuate at 200 F.Caused by Setpoint Drift.Switch Recalibr & Satisfactorily Tested ‎ (← links)
  • 05000278/LER-1989-008-03, :on 891027,primary Containment Isolation Sys Group II & III Isolations Occurred When Spurious Reactor Low Level Signal Sensed by Instruments.Possibly Caused by Air Bubble in Sensing Lines.Line Backfilled ‎ (← links)
  • 05000278/LER-1989-007-04, :on 891026,reactor Vessel Temp & Reactor Coolant Pressure Not Logged Every 15 Minutes as Required by Tech Spec 4.6.A.2 During Performance Integrated Leak Rate Testing.Caused by Procedure Deficiency ‎ (← links)
  • 05000278/LER-1989-006-04, :on 891023,during Reactor Temp Adjustment, Reactor High Pressure Scram Occurred.Caused by Improper Planning & Coordination of Multiple Evolutions.Surveillance & Hydrostatic Test Revised ‎ (← links)
  • 05000278/LER-1989-005-03, :on 891020,reactor Protection Sys Actuation & Primary Containment Isolation Sys Actuation Occurred Due to False High Reactor Pressure Signal & lo-lo Reactor Vessel Level Signal,Respectively.Caused by Spike ‎ (← links)
  • 05000278/LER-1980-020-03, /03L-0:on 800815,while Performing Leak Test, Containment Ventilation Valve AO-3521B Was Found Leaking Excessively.Caused by Valve T-ring Inflating Before Closure.Air Valves Adjusted & Valve Tested ‎ (← links)
  • 05000278/LER-1980-011-03, /03L-0:on 800516,during Power Operation,Instrument Surveillance Test Revealed Setpoint for Pressure Switch 3-2-128B at 33 Psi Above Tech Spec.Caused by Barksdale Model PIH-M8555-V Pressure Switch Setpoint Drift ‎ (← links)
  • 05000278/LER-1980-012-03, /03L-0:on 800520,during Full Power Operation, Routine Testing Revealed Pressure Switch 5121B Setpoint at 700 Psi Above Tech Spec.Caused by Personnel Error.Setpoint Adjusted.Technician Instructed ‎ (← links)
  • 05000278/LER-1980-015-03, /03L-0:on 800707,during Full Power operation,3A Refuel Floor Exhaust Rad Monitor Found Drifting Downscale. Cause Has Not Been Determined.New Gm Tube & Electronic Circuitry Installed ‎ (← links)
  • 05000278/LER-1980-016-01, /01T-0:on 800717,reanalysis by Bechtel of as-built Piping Determined That Stresses on Snubber 3-10-GB-S-44 Exceeded Operability Criteria.Caused by Inadequate Design Due to as-built Condition & Seismic Analysis Info Variance ‎ (← links)
  • 05000278/LER-1980-016, Forwards LER 80-016/01T-0 ‎ (← links)
  • 05000278/LER-1989-004-03, :on 890926,Group Iia Primary Containment Isolation Actuated Closing of RWCU Sys Isolation Valve & Tripping RWCU Pump 3B.Caused by Personnel Error.Isolation Logic Reset & Individual Counselled ‎ (← links)
  • 05000278/LER-1989-003-03, :on 890808,subsequent Sys Walkdown & Analysis Revealed That as-found Configuration Would Result in Piping Stresses Adjacent to Valves Exceeding Code Limits.Caused by Design & Installation Error ‎ (← links)
  • 05000278/LER-1980-010-03, /03L-0:on 800421,while Performing Surveillance Test,Lpci Injection valve,MO-3-10-25B,failed to Open.Caused by Lack of Guide Clearance Between Valve Disc & Valve Guide. Valve Was Repaired & Stroked Satisfactorily ‎ (← links)
  • 05000278/LER-1980-009-03, /03L-0:on 800414,during Normal Operation,Shift Personnel Verified Reported Leak at Suction Piping Header one-inch Drain Line Connection on D RHR Pump.Caused by Fatigue Failure of Pipe.Pump Suction Line Repaired ‎ (← links)
  • 05000278/LER-1980-003-03, /03L-0:on 800303,while Performing Surveillance tests,MO-3-10-25A LPCI on A,Loop Failed to Open & RHR Pump Would Not Start.Caused by Galled Walworth 24-inch Gate, Pressure Seal Bonnet.Valve Repaired & Leak Tested ‎ (← links)
  • 05000278/LER-1980-008-01, /01T-0:on 800305,while at power,E334 Load Ctr Was Shed Automatically Due to Loss of Site Startup Source,But Failed to Recover Automatically.Caused by Agastat Time Delay relay,Model7012PC,not Picking Up on Restoration ‎ (← links)
  • 05000278/LER-1980-008, Forwards LER 80-008/01T-0 ‎ (← links)
  • 05000278/LER-1980-014-03, /03L-0:on 800608,while Performing ST 6.9,valve Mo 3-10-26B Failed to Close After Stroked Open.Caused by Mechanical Problem in Valve.Mo 3-10-26B to Be Disassembled & Repaired ‎ (← links)
  • 05000278/LER-1980-013-03, /03L-0:on 800605,during Surveillance Test,Pressure Switch Ps 3 5 12C Found 0.3 Psig Above Tech Spec Limit. Caused by Setpoint Drift.Switch Recalibr,Tested & Returned to Svc ‎ (← links)
  • 05000278/LER-1980-006-03, /03L-0:on 800213,while at Power,Reactor Core Isolation Cooling Automatic Control from Control Room Found Inoperable.Caused by Logic Circuit Board Failure in Pump Discharge Flow Controller.Defective Controller Replaced ‎ (← links)
  • 05000278/LER-1980-007-01, /01T-0:on 800221,during Routine Plant Equipment Insp,Seismically Qualified Backup Nitrogen Bottle Supplies to Five Containment Ventilation Valves Found Out of Svc. Caused by Lack of Operator Info & Equipment Identification ‎ (← links)
  • 05000278/LER-1980-007, Forwards LER 80-007/01T-0 ‎ (← links)
  • 05000278/LER-1980-004-03, /03L-0:on 800205 During Plant Startup,Reactor Water Conductivity Increased & Exceeded Tech Spec Limits. Caused by Resin Injection.Reactor Was Shut Down & Primary Coolant Chemistry Brought within Tech Spec Limits ‎ (← links)
  • 05000278/LER-1980-004, Forwards LER 80-004/03L-0 ‎ (← links)
  • 05000278/LER-1980-002-03, /03L-0:on 800118,while at Power During Insertion of Tip Probe 5 Into Core,Tip Probe Inshield Light Came On. Probe Could Be Inserted,But Not Withdrawn.Caused by Tip Inshield Limit Switch Being Out of Calibr ‎ (← links)
  • 05000278/LER-1980-001-03, /03L-0:on 800106,during Surveillance Tests,Main Steam Line Radiation Monitor D Failed to Actuate hi-hi Trip to Initiate Channel B one-half Scram & Group 1 Isolation. Cause Unknown.Monitor Replaced ‎ (← links)
  • 05000278/LER-1978-024-03, /03L-0 on 781212:reactor Core Isolation Cooling Valve Mo-13-15 Failed to Close During Surveillance Test 6.11.Caused by Cocked Packing Follower Jamming Valve Stem ‎ (← links)
  • 05000278/LER-1979-006-03, /03L-1 on 790212:at Power & During Surveillance Test,Setpoint of B Core Spray Pump Start Timer Was Less than Tech Spec Min.Caused by Setpoint Drift on GE Model CR-2820 Time Delay Relay.Relay Readjusted & Tested ‎ (← links)
  • 05000278/LER-1979-007-03, /03L-0 on 790212:during Surveillance,Setpoint of a Logic Automatic Depressurization Sys Time Delay Relay Was Greater than Tech Spec Limit.Caused by Setpoint Drift on GE Model CR-2820 Time Delay.Relay Readjusted & Tested ‎ (← links)
  • 05000278/LER-1979-009-03, /03L-0 on 790307:calculated Torus Water Level Did Not Provide Proper Torus Water Vol Per Tech Spec.Caused by Failure to See Pressure Differential Between Drywell & Torus Holds Level in Downcomers Was Below Torus Level ‎ (← links)
  • 05000278/LER-1979-002-01, /01T-0 on 790108:roof Vent Stack Instantaneous Gas Release Rate Above Tech Spec Limit Due to Valve Operator Failure,Causing Loss of Inservice RHR Loop,Rise in Coolant Temp & Gaseous Release Via Core Isolation Cooling Valves ‎ (← links)
  • 05000278/LER-1979-002, Forwards LER 79-002/01T-0 ‎ (← links)
  • 05000278/LER-1979-004-03, /03L-0 on 790117:during Surveillance Test,Setpoint of PS-3-14-44D Found to Be Greater than Tech Spec Max.Caused by Setpoint Drift on static-o-ring Model 5N-AA3 Pressure Switch.Instrument Recalibrated ‎ (← links)
  • 05000278/LER-1979-001-03, /03L-0 on 790111:discovered That Recorded hi-hi Trip Valve for Steam Line Radiation Monitor Was 50 man-rem/h Greater than Tech Spec Limit & No Corrective Action Taken. Caused by Procedural Deficiency ‎ (← links)
  • 05000278/LER-1979-037-03, /03L-0:on 791113,during Surveillance Testing on Rod Sequence Control Sys,Sequence Mode Found Inoperable. Caused by Failure in Integrated Circuit Chip on Sequence Logic Board.Integrated Circuit Chip Was Replaced ‎ (← links)
  • 05000278/LER-1979-019-01, /01T-0 on 790621:during Seismic Support Insp Program, Reactor Core Isolation Cooling Piping Anchor Discovered to Have Two Bolts That Could Not Be Torqued. Caused by Improper Installation of Bolt Shells ‎ (← links)
  • 05000278/LER-1979-011-01, /01T-0 on 790323:during Routine Insp of Drywell & Torus Ventilation Valves,Inflatable Disc Seals Were Found Depressurized.Caused by Procedural Deficiency Following Mod to Drywell & Torus Vent Valves.Procedures Revised ‎ (← links)
  • 05000278/LER-1979-011, Forwards LER 79-011/01T-0 ‎ (← links)
  • 05000278/LER-1979-003-03, /03L-0 on 790111:during Unit Shutdown for Maint an Instrument Shutoff Valve to Pressure Switch Found Closed Due to Personnel Error.Unit Operated 9 Days W/Instrument Out of Svc.Appropriate Disciplinary Action Taken ‎ (← links)
  • 05000278/LER-1979-030-01, /01T-0:on 791002,rigid Hanger Failed Due to Contact Between Two of Four Bolts & Base Plate.Caused by Improper Installation.Two shell-type Bolts Were Replaced W/ wedge-type Bolts & Plate Washers Were Installed ‎ (← links)
  • 05000278/LER-1979-030, Forwards LER 79-030/01T-0 ‎ (← links)
  • 05000278/LER-1979-028-03, /03L-0:on 790910,main Steam Tunnel High Temp Switch TS 5932C Failed to Initiate Logic a Group I Isolation.Caused by Dirty Contacts on Temp Switch Circuit Board.Contacts Cleaned.Temp Switch Returned to Svc ‎ (← links)
  • 05000278/LER-1979-039-01, /01T-0:on 791130,engineering Review Per IE Bulletin 79-02 Identified 16 Supports Associated w/1-inch Control Rod Driveline Insert & Withdrawal Piping as Not Being Seismically Qualified.Caused by Inadequate Design ‎ (← links)
  • 05000278/LER-1979-039, Forwards LER 79-039/01T-0 ‎ (← links)
  • 05000278/LER-1979-038-01, /01T-0:on 791120,during Review of Surveillance Test,Two MSIVs in a Steamline Closed in Times Shorter than Specified in Tech Specs.Caused by Operator Not Recognizing Fast MSIV Closure Time.Operator Procedure Revised ‎ (← links)
  • 05000278/LER-1979-038, Forwards LER 79-038/01T-0 ‎ (← links)
  • 05000278/LER-1979-035-03, /03L-0:on 791102,during Insp of Traveling in Core Probe Sys,Shear Valves in Guide Tube Assemblies Detected Installed Backwards.Caused by Facility Const Error.Five Shear Valves Removed & Properly Reinstalled ‎ (← links)
  • 05000278/LER-1978-014-03, /03L-0:on 780626,at Power Operation,Shutoff Valve on Pressure Switch Found Closed.Caused by Closure During 780621 Testing.Valve Reopened & Valving for Safety Instrumentation Checked ‎ (← links)
  • 05000278/LER-1979-031-01, /01T-0:on 791003,rigid angle-iron Hanger Bolts Found Detached & Hanger Nonfunctional.Caused by Improper Installation.Two Anchor Bolts Were Replaced w/wedge-type Anchor Bolts ‎ (← links)
  • 05000278/LER-1979-031, Forwards LER 79-031/01T-0 ‎ (← links)
  • 05000278/LER-1979-032-01, /01T-0:on 791005,seismic Support Associated W/ Emergency Svc Water Return Line Failed.Two of Four Bolts on Support Plate Failed to Meet Torque Requirements.Caused by Improper installation.Shell-type Bolts Replaced ‎ (← links)
  • 05000278/LER-1979-032, Forwards LER 79-032/01T-0 ‎ (← links)
  • 05000278/LER-1979-027-03, /03L-0:on 790909,during Surveillance Test Performance,High Pressure Svc Water Pump 3D Tripped.Caused by Insecure Motor Leads of High Pressure Svc Water Pump Motor.Procedures Will Be Modified ‎ (← links)
  • 05000278/LER-1979-026-01, /01T-0:on 790904,anchor 3-23-DDN-525 Identified as Failure.Caused by Improper Installation.Anchor Plates Attached to New Plates by Means of Fillet Welds ‎ (← links)
  • 05000278/LER-1979-026, Forwards LER 79-026/01T-0 ‎ (← links)
  • 05000278/LER-1979-022-03, /03L-0 on 790719:annunciator Sys II Drywell Pressure Permits Containment Spray Alarmed During Routine Startup.Caused by Failure of Diaphragm on PS-3-10-119D. Switch Repaired,Tested & Returned to Svc within Five Days ‎ (← links)
  • 05000278/LER-1979-016-03, /03L-0 on 790628:while at Power,Routine Surveillance Test Revealed Setpoint of Switch 2 Was Below Tech Spec Min.Caused by Barton Model 288 Instrument Out of Calibr from Drift.Instrument Recalibr ‎ (← links)
  • 05000278/LER-1979-017, Discusses LER 79-017/03L-0.While Reactor Subcritical & Less than 212 F,Main Steam Line D Radiation Monitor Hi-Hi Trip Failed.Caused by Dirty Trip Relay or Dirty Test Switch Contacts.Repeated Testing Corrected Condition ‎ (← links)
  • 05000278/LER-1979-019, Forwards LER 79-019/01T-0 ‎ (← links)
  • 05000278/LER-1979-013-01, /01T-0 on 790613:main Steam Relief Valve RV3-2-71L Lifted,Causing Torus Water Vol to Exceed Tech Spec Limit by 2.6%.Reactor Manually Scrammed.Valve Replaced & Sent to Wiley Lab to Determine Cause for Failure ‎ (← links)
  • 05000278/LER-1979-013, Forwards LER 79-013/01T-0 ‎ (← links)
  • 05000278/LER-1979-018-03, /03L-0 on 790630:during Surveillance Testing, Reactor Water Sample Line Isolation Valve Failed to Close. Caused by Lack of Valve Operator Spring Tension.Valve Operator Spring Tension Was Increased ‎ (← links)
  • 05000278/LER-1979-017-31, /03L-0 on 790615:while Reactor Subcritical,D Main Steam Line Radiation Monitor Hi-Hi Trip Failed.Caused by Dirty Trip Relay or Dirty Test Switch Contacts. Condition Corrected by Repeated Testing ‎ (← links)
  • 05000278/LER-1979-020-01, /01T-0 on 790621:radioactive Release Rate at Main Stack During Plant Startup Exceeded Tech Specs.Caused by Deficiency in Procedure for Depressurization Following Shutdown.Investigation Underway to Improve Procedure ‎ (← links)
  • 05000278/LER-1979-020, Forwards LER 79-020/01T-0 ‎ (← links)
  • 05000278/LER-1979-034-03, /03L-0:on 791101,during Surveillance Testing, Standby Liquid Control Pump Relief Valve Operated Below Tech Spec Limit.Caused by Setpoint Drift on Jmsk Crosby Valve. Valve Readjusted within Tech Spec Limit ‎ (← links)
  • 05000278/LER-1979-033-03, /03L-0:on 791022,while in Cold Shutdown for refueling,3D RHR Pump Tripped on Overcurrent.Caused by Internal Motor Fan Blade Fatigue Failure.Stator Insulation Repaired & Bottom Fan Installed ‎ (← links)
  • 05000278/LER-1979-025-03, /03L-0:on 790829,during Tests,Reactor Vessel Relay 2E-K18 Failed.Caused by Worn Contact on GE Hfa Relay.Logic Channel Placed in Tripped Conditon & Relay Will Be Replaced During Refueling & Maint Outage ‎ (← links)
  • 05000278/LER-1979-024-01, /01T-0:on 790815,during Response Tests for IE Bulletin 79-02,three or Four Failed Anchor Bolts Were Found on Support to 3D RHR Pump Section Piping.Caused by Improper Installation.Bolts Replaced & Passed Insp ‎ (← links)
  • 05000278/LER-1979-024, Forwards LER 79-024/01T-0 ‎ (← links)
  • 05000278/LER-2074-033, Reporting Abnormal Occurrence No. 50-278-74-33 at Peach Bottom Atomic Power Station for Failure of Main Steam Line High Flow Switch dPIS-3-2-116C to Trip During Surveillance Test ‎ (← links)
  • 05000278/LER-2018-002-01, Reactor Coolant System Pressure Boundary Leakage Resulting in Technical Specification Required Shutdown ‎ (← links)
  • 05000278/LER-2018-004, Failure of a Main Steam Isolation Valve to Fully Close ‎ (← links)
  • 05000278/LER-2018-003, Automatic Reactor Scram Due to Loss of Two Condensate Pumps ‎ (← links)
  • 05000278/LER-2018-002, Reactor Coolant System Pressure Boundary Leakage Resulting in Technical Specification Required Shutdown ‎ (← links)
  • 05000278/LER-2018-001, Reactor Core Isolation Cooling System Pressure Switch Failure Results in Condition Prohibited by TS ‎ (← links)
  • 05000278/LER-1917-001, Regarding Reactor Pressure Boundary Leakage Due to Weld Failure in One-Inch Diameter Instrument Line ‎ (← links)
  • 05000278/LER-2016-001, Regarding Leak in High Pressure Coolant Injection Drain Pipe Results in a Loss of Safety Function ‎ (← links)
  • 05000278/LER-2015-001, Regarding Loss of High Pressure Coolant Injection System Function as a Result of Failed Flow Controller Signal Converter ‎ (← links)
  • 05000278/LER-2013-001, Re Laboratory Analysis Identifies Safety Relief Valves and Safety Valve Set Point Deficiencies ‎ (← links)
  • 05000278/LER-2012-003, Regarding Loss of Control Room Emergency Ventilation Function Due to Failure of Ventilation Fan to Start ‎ (← links)
  • 05000278/LER-2012-002, Regarding Failure of Primary Containment Isolation Valve Due to Foreign Material Results in Condition Prohibited by TS ‎ (← links)
  • 05000278/LER-2012-001, For Peach Bottom Atomic, Unit 3 Regarding Concurrent Inoperability of Two Trains of Core Spray Pressure Switches Results in Condition Prohibited by TS ‎ (← links)
  • 05000278/LER-2011-004, Regarding HPCI Cable Routing Error Results in Degraded Post Fire Safe Shutdown (Fssd) Analysis ‎ (← links)
  • 05000278/LER-2011-001, Regarding Containment Isolation Valve Inability to Close for a Design Basis Event Due to Degraded Lubricant ‎ (← links)
  • 05000278/LER-2011-003, For Peach Bottom Unit 3, Regarding Automatic Depressurization System Safety Relief Valve Actuator Diaphragm Thread Seal Leak ‎ (← links)
  • 05000278/LER-2011-002, For Peach Bottom Unit 3 - Residual Heat Removal Leaking Relief Valve Results in Condition Prohibited by Technical Specifications ‎ (← links)
  • 05000278/LER-2009-007, Regarding Oil Leak from Main Steam Isolation Valve Dashpot Results in Short Valve Stroke Time ‎ (← links)
  • 05000278/LER-2009-006, Regarding Unplanned Manual Scram Due to Shortening Reactor Period During Scheduled Shutdown ‎ (← links)
  • 05000278/LER-2009-005, Common Cause Failure of C and E Wide Range Neutron Monitors ‎ (← links)
  • 05000278/LER-2009-004, Regarding Inoperable Ventilation Fan Results in Condition Prohibited by Technical Specifications ‎ (← links)
  • 05000278/LER-2009-003, Inoperable Containment Isolation Valve Results in Condition Prohibited by Technical Specifications ‎ (← links)
  • 05000278/LER-2009-002, Regarding Inoperable a Wide Range Neutron Monitor Results in Condition Prohibited by Technical Specifications ‎ (← links)
  • 05000278/LER-2009-001, Regarding Control Rods Inoperable During Mode 2 Operations as a Result of Interferences ‎ (← links)
  • 05000278/LER-2007-001, Laboratory Analysis Identifies Safety Relief Valves and Safety Valve Set Point Deficiencies ‎ (← links)
  • 05000278/LER-2006-004, For Peach Bottom, Units 2 and 3, Regarding Plant Modification Created Diesel Generator Building Carbon Dioxide Suppression Room Flooding Vulnerability ‎ (← links)
  • 05000278/LER-2006-001, Regarding Technical Specification Non-Compliance Due to Inoperable Primary Containment Isolation Valve ‎ (← links)
  • 05000278/LER-2005-004, Re Laboratory Analysis Identifies Safety Relief Valve Set Point and Performance Deficiencies ‎ (← links)
  • 05000278/LER-2005-003, Re Residual Heat Removal System Small Bore Piping Leak Due to Weld Deficiency ‎ (← links)
  • 05000278/LER-2005-002, Regarding Technical Specification Non-Compliance Due to a Unit 3 HPCI Suction Valve Logic Limit Switch Out of Adjustment ‎ (← links)
  • 05000278/LER-2005-001, Regarding Loss of High Pressure Coolant Injection System Function as a Result of Inoperable Flow Controller ‎ (← links)
  • 05000278/LER-2004-003, Re Technical Specification Non-Compliance Due to Loose Wire on a HPCI Suction Valve Logic Relay ‎ (← links)
  • 05000278/LER-2004-002, Loss of High Pressure Coolant Injection System Automatic High Level Trip as a Result as a Result of Lifted Lead ‎ (← links)
  • 05000278/LER-2004-001, Re Loss of High Pressure Coolant Injection System Function as a Result of Inoperable Flow Controller ‎ (← links)
  • 05000278/LER-2003-001, Loss of Capability of the 10CFR.50 Appendix R Alternate Control Station ‎ (← links)
  • 05000278/LER-2001-002, Less than Adequate Test Review Results in Low Pressure Emergency Core Cooling Safety Function Degradation ‎ (← links)
• ML031900043 (redirect page) ‎ (← links)
• 05000277/LER-2003-004, Regarding Automatic Scrams Resulting from an Off-Site Electrical Grid Disturbance ‎ (← links)
• 05000277/LER-2003-003, Generator Bus Ground Caused by Foreign Material Results in Automatic Scram ‎ (← links)
• 05000277/LER-2003-002, Regarding Condition Prohibited by Technical Specifications Due to Inoperability of Standby Gas Treatment Filter Train ‎ (← links)
• 05000277/LER-2003-001, Regarding Outboard Main Steam Isolation Valve Instrument All Line Failure Results in Scram on Reactor High Pressure ‎ (← links)