NG-13-0102, Response to Request for Additional Information, License Amendment Request to Adopt National Fire Protection Association Standard 805, Performance-Based Standard for Fire Protection for Light Water Reactor Generating Plants
WM 16-0008, Wolf Creek Generating Station, Redacted Version of Revision 29 to Updated Safety Analysis Report, Chapter 6.0 - Engineered Safety Features
NL-15-1392, Enclosure 9 - Hatch Justification Matrix
NL-15-1392, Enclosure 6 - Farley Justification Matrix
RC-14-0032, Virgil C. Summer Unit 1, License Amendment Request LAR-14-02392, Request for NRC Approval of Proposed Changes to Emergency Action Levels. Attachments Iii, Iv, V & Vi: Technical Bases for Proposed EALs (Clean Copy), NEI 99-01 Revision 6 EA
NL-08-009, Indian Point Energy Center - Hydrogeologic Site Investigation Report - Appendix H Through I
05000416/LER-1989-016, :on 891107,during Severe Thunderstorm,Lightning Struck Site,Causing Scram & HPCS Low Water Level Channels to Trip.Design Change Package Issued to Install Lightning Dissipation Sys on Vulnerable Structures
05000316/LER-1985-043, Resubmitted LER 85-043-00:on 851227,auxiliary Bldg Ventilation Grab Sample Not Obtained within Tech Spec Time Constraints.Caused by Personnel Error.Administrative Action Taken W/Individual Involved
IA-86-669, Partial Response to FOIA Request for Info Re Generic Safety Issues & Gimcs.Forwards App C Document.App B & C Documents Available in PDR
ST-HL-AE-5333, Forwards Response to NRC Bulletin 96-001, Control Rod Insertion Problems
3F1295-22, Forwards Evaluation Results Re Insp Rept 50-302/95-22.Rept Included Review of Unauthorized Make-Up Tank Evolutions of 940904-05 & Verified Other Make-up Tank Info Recently Given to Util
05000412/LER-1989-006, :on 890116,component Cooling Pump C Exhibited Sudden Loss of Flow & Immediately Secured.Caused by Expansion Joint Liner/Weld Failure,Allowing Liner to Be Drawn Into Pump Impeller.Part 21 Related
05000277/LER-1989-019-01, :on 890830,discovered That Five Doors Requiring Monthly Functional Tests,Per Tech Specs,Not Included on Surveillance Test.Caused by Deficiency in Methodology & Refs Used During Surveillance
05000259/LER-1988-036, :on 881018,unanalyzed Conditions Identified Re Loading & Sequencing of Loads on safety-related Electrical Distribution Sys.Caused by Inadequate Design Control & Review Program at Time of Original Design
05000259/LER-1989-011-02, :on 890503,determined That Emergency Equipment Cooling Water anti-siphon Check Valves Have Potential for Transporting Uncontrolled & Unfiltered Secondary Containment Atmosphere to Outside Atmoshere
05000327/LER-1989-013, :on 890503,train B Control Room Isolation Signal Received in Main Control Room.Caused by Operator Bumping Radiation Monitor Pump Motor Breaker While Changing Recorder Chart Paper.Chart Paper Replaced
05000425/LER-1989-019, :on 890502,overspeed Trip Device Malfunctioned During Weekly Turbine Trip Device Operability Test.When Button Pushed Turbine Tripped,Resulting in Reactor Trip. Caused by Defective Weld Joint.Weld Repaired
05000293/LER-1989-021, :on 890615,automatic Actuation of Inboard & Outboard RWCU Sys Portion of Primary Containment Isolation Sys Occurred.Caused by Air in Sensing Lines of RWCU Sys Flow Sensors.Lines Bled to Eliminate Air
05000412/LER-1989-016, :on 890427,radwaste in Transit Not Properly Posted.Caused by Failure of Prework Briefing to Discuss Disposition of Mop Heads & Failure of Technician to Tag Bag. Checklist Will Be Developed
05000302/LER-1989-025, :on 890629,plant Separated from Normal Offsite Power Source.Electrical Storm Was in Progress.Caused by Electrical Fault in 230 Kv Switchyard.Damaged Current Transformer Replaced
05000412/LER-1989-012, :on 890427,technicians Failed to Identify & Block Trip Signal to Train a 4-kV Emergency Bus Feeder Breaker,Causing Loss of Power to Train a Emergency Bus. Operators Counseled & Relay Testing Evaluated
05000341/LER-1989-013, :on 890624,reactor Bldg HVAC Isolated & Standby Gas Treatment Sys Automatically Started.Caused by Personnel Error.Potential Design Change Written to Improve Testability at Panel
05000483/LER-1989-002, :on 890228 & 0303,unplanned ESF Actuations Occurred.Caused by Shield Breakage of Coaxial Cable & Technician Inadvertent Push of ESF Actuation Push Button, Respectively.Cable Replaced
05000416/LER-1989-013, :on 890814,MSIV B21F022B Failed to Close Upon Demand from Automatic & Remote Manual Actuation Signals. Caused by Elastomer Seat Matl Extruding Into Exhaust Port Vent Hole.Dual Valves Replaced.Part 21 Related
05000458/LER-1989-021, :on 890427,during Refueling,Unplanned ESF Actuation Occurred.Caused by Power Transient to Several Trip Cards Resulting from Shorting of Test Connection.Rhr Shutdown Cooling Restored & Actuation Reset
05000327/LER-1988-047, :on 881225,erratic Feedwater Controls Caused Feedwater Isolation on hi-hi Steam Generator (S/G) Level & Resulted in Reactor Trip.Caused by Difficulty in Controlling S/G Levels.Valve Controllers fine-tuned
05000412/LER-1989-019, :on 890622,plant Shut Down Due to Tube Leak in Steam Generator C.Caused by Operating Shift Performing Numerous Concurrent Tasks While Controlling Steam Generator Levels.Event Reviewed W/All Licensed Operators
05000499/LER-1989-012, :on 890414,radiation Monitor on Fuel Handling Bldg Exhaust Air Duct Went Into High Alarm & Actuated HVAC Sys.Caused by Clogged Filter on Radiation Monitor.Sample Lines from Duct to Monitor Will Be Checked
05000369/LER-1988-048, :on 880822,noted That Shrinkage of Boraflex Neutron Absorbing Matl Could Cause Increase in Reactivity, Per NRC Info Notice 87-043.Caused by Design Deficiency.Util & Westinghouse Performed Analyses
05000458/LER-1989-030, :on 890617,pressure Transmitter Root Valve for Penetration Valve Leakage Control Sys Found Closed.Caused by Personnel Error & Misapplication of Test Tagging Procedure. Root Valve Opened & Control Sys Restored
05000293/LER-1989-025, :on 890805,HPCI Sys Declared Inoperable & 7-day Tech Spec Limiting Condition for Operation Entered.Caused by Failure of Gland Seal Condenser Blower Motor to Start.Blower Motor Brushes Replaced & Blower Tested
05000298/LER-1989-007, :on 890217 Svc Water Sys Flowrate Concerns Associated W/ Original Sys Design Identified During NRC Insp NRC Insp on 870511-0619.Caused by Inadequate Design. Reduction of Diesel Generator Room Temps Being Pursued
05000327/LER-1989-018-01, :on 890619,discovered That Both Trains of Auxiliary Bldg Gas Treatment Sys (ABGTS) Automatic Actuation Could Have Been Rendered Inoperable.Caused by Removal of Radiation Monitor During Testing
05000334/LER-1989-005-01, :on 890416,motor-operated Valve MOV-RW-116B & Auxiliary River Water Sys Supply Valve to Normal River Water Header B Opened & Header Pressure Dropped to Low Setpoint. Caused by Failed Reach Rod.Valve Closed
05000324/LER-1989-010-02, :on 890619,unit Received Group 1 Isolation While in Hot Shutdown W/Reactor Pressure at 150 Psig.Caused by High Steam Flow Isolation Signal.No Corrective Measures Considered Necessary
05000458/LER-1989-017, :on 890407,determined That intermediate-range Monitor Surveillance Test Procedures Not Performed within Allowable Tech Spec Schedule Tolerance.Caused by Scheduling Error.Manual Changes Will Be Verified
05000339/LER-1989-002-02, :on 890220,two Valves Which Isolate Flow from Discharge Header of Lhsi Pumps to Cold Legs of RCS Simultaneously Closed During Hydrostatic Tests.Caused by Need to Provide Overpressure Protection
05000298/LER-1989-012, :on 890407,actuation of ESF Group Isolations Occurred Subsequent to Planned Manual Scram.Caused by design.State-of-the-art Digital Turbine Control Sys Being Installed
05000325/LER-1988-033, :on 881214,determined That Valve Body Erosion Generic Concern on Both Units.Erosion Resulted from Flow Induced Cavitation Due to Throttling Isolation Valves Below Design Limit.Instructions Re RHR Loops Revised
05000338/LER-1988-022, :on 881013,determined That Various Pipes in Safety Injection Sys & Chemical Vol & Control Sys Collected or Trapped Gas Which Might Affect Functions of Sys.Caused by Not Completely Venting Sys After Refill
05000423/LER-1989-011-01, :on 890527 & 0603,as-found Local Leak Rate Testing Containment Unfiltered Leakage Exceeded Tech Spec Limit.Caused by Poor wedge-to-seat Fit.Wedge Angle Changed & Valve Seats Resurfaced to Ensure Proper Seal
05000412/LER-1989-023, :on 890804,identified Potential Generic Problem W/Westinghouse Solid State Protection Sys Auxiliary Relays. Mod Made to Control Circuits for Valves.Relays Rewired to Use Two Pairs of Contacts.Part 21 Related
05000346/LER-1988-029, :on 881218,control Rod Group 3 Safety Rods Dropped Into Core as Result of Troubleshooting in CRD Sys Causing Reactor to Go Subcritical.Caused by Personnel Error. Maint Personnel Trained
05000483/LER-1989-005, :on 890518,ESF Safety Injection Actuation on Train a Received Due to Low Steamline Pressure Signal During Operational Test.Caused by Personnel Error.Procedure Revised
05000213/LER-1989-004, :on 890125,flood Protection of Main Diesel Fuel Oil Tank Determined Inadequate.Caused by Design, Analysis &/Or Procedural Inadequacies.Probability of Flood Occuring During Spring of 1989 Analyzed
05000260/LER-1989-010-01, :on 890323,radiation Monitor Experienced Downscale Spike Following Upscale Spike,Resulting in Unplanned ESF Actuations.Caused by Arcing from Exposed Conductors on Communication Line.Cord Taped
05000352/LER-1989-036, :on 890525,pressure Setpoint Testing of 14 Reactor Main Steam Sys Target Rock Corp Pilot Operated two- Stage Safety Relief Valves Revealed That Only One Valve Lifted within Tech Specs Limit
05000425/LER-1989-012, :on 890330,while Performing Maint,Technician Inadvertently Placed 2RE-2562A & 2RE-2562C in Purge Instead of Activating Paper Drive on 2RE-2562A.Caused by Technician Failing to Pay Attention to Detail
05000352/LER-1989-019, :on 890314,informed That Certain Electrical Equipment Located in High Energy Line Break Compartment May Not Perform Intended Safety Function,Causing Reliance on Unqualified Equipment.Environ Seals Added
05000346/LER-1988-025, :on 881129,inadvertent Initiation of Steam & Feedwater Rupture Control Sys Occurred While Filling & Draining Steam Generators.Caused by Personnel Error.Standing Order Issued to Provide Control Band
05000333/LER-1989-007-01, :on 890509,surveillance of Fire Barrier Penetrations Missed Due to Misinterpretation of Barriers. Fire Watch Established & Required Surveillance Completed & Ref Manual Revised
05000334/LER-1989-003-01, :on 890311,actuation of Control Room Emergency Breathing Air Pressurization Sys Occurred.Caused by Electrical Failure High of a Train Control Room Radiation Monitor.Control Room Radiation Level Verified
05000327/LER-1988-033, :on 881004,unplanned Reactor Trip Signal Generated Due to Reactor Protection Sys (RPS) Channel I Instrument Failure During RPS Channel II Calibr.Possibly Caused by Component Aging
05000317/LER-1989-005, :on 890314,instrument Air Boundary Check Valve Determined by Test to Allow Excessive Back Leakage.Caused by Matl Wear Causing Poor Seating Surface.Check Valve Isolated & New Flow Path Was Initiated
05000341/LER-1987-038, :on 870815,automatic Initiation of Div I Emergency Equipment Cooling Water (EECW) Occurred.Caused by Inadequate Sys Design for Pressure compensation.Motor- Operated Valves Installed to EECW Makeup Tanks
05000271/LER-1998-021, :on 980803,noted Failure to Meet IST Requirements for Diesel Fuel Oil Day Tank Level Control Valves.Caused by Inadequate Licensing Basis Documentation Retrievability.Subject Valves Were Tested
05000413/LER-1987-031, :on 870729,vent Gas Radiation Monitor Found Inoperable.Caused by non-conservative High Radiation Alarm Setpoint.Setpoint Returned to Original Setting & Policy Will Be Clarified
05000461/LER-1987-042, :on 870812,reactor Scrammed on High Flux on APRM Channels B & D.Caused by Personnel Failure to Follow Procedures.Training Provided for Control & Instrumentation & Startup Personnel
05000461/LER-1987-044, :on 870730,violation of Plant Tech Spec 4.3.1.1,Table 4.3.1.1-1,Item 2a Occurred.Caused by Personnel Error Resulting from Procedural Deficiency.Procedure Revised to Ensure Thorough Channel Check
05000327/LER-1987-052, :on 870723,potential Problem Identified W/ Emergency Diesel Generator Speed During Containment Spray Pump Startup Following Phase B Containment Isolation.Caused by Design Error.Procedures Established
05000483/LER-1987-016, :on 870625,monthly Sampling & Analysis of Unit Vent Gaseous Effluents Not Performed as Required by Tech Specs.Caused by Personnel Error.All Technicians Instructed to Follow Appropriate Surveillance Procedures
05000245/LER-1987-043, :on 871116,hydraulic Snubbers HSS-21 & HSS-95 Found to Be Low on Hydraulic Fluid & Declared Inoperable on Testing.Caused by Displaced O-rings.Snubbers Rebuilt, Retested & Reinstalled
05000423/LER-1987-042-01, :on 871117,Tech Spec Surveillance Requiring Measuring Detector Plateau Curve for Each intermediate-range & power-range Neutron Detector Not Performed.Caused by Procedural Inadequacy.New Procedure Written
05000498/LER-1987-012, :on 871102,high Head Safety Injection Sys Cold Leg Injection Valves Closed.Caused by Inadequate Training & Personnel Error.Mgt Reemphasized Proper Use of Procedures, Annunciators & Attention to Details
05000414/LER-1987-030-01, :on 871105,feedwater Isolation Signal Generated in hi-hi Steam Generator.Caused by Technician Failure to Correctly Identify Root Valve Associated W/Inoperable Level Transmitter.Root Valve Reopened
05000336/LER-1987-012-01, :on 871116,reactor Tripped on Low Steam Generator Level.Caused by Failure of Feedwater Regulating Valve to Respond to Closing Signals from Control Board in Automatic or Manual Modes
05000461/LER-1987-065, :on 871104,reactor Tripped Due to Decay of Containment Air Header Pressure During Div 2 Surveillance. Caused by Inadequate Surveillance Procedure & Operator Error.Rev Planned
05000259/LER-1987-029-01, :on 871105,ESF Actuations Occurred During Mod Activities.Caused by Personnel Error.Individuals Involved Cautioned
05000267/LER-1987-025, :on 871030,offsite Electrical Power Lost When Reserve Auxiliary Transformer (RAT) Deluge Actuated.Caused by Installation Error.Rat Deluge Sys Reset & Electrical Power Restored
05000412/LER-1987-031, :on 871020,leaks Discovered Through Clamp on RCS Loop a Cold Leg Bypass Isolation Valves 2RCS*44,2RCS*37 & 2RCS*46 in Excess of Tech Spec Limits.Cause Undetermined. Valves Repaired or Replaced
05000245/LER-1987-023-01, :on 870708,insp of Core Spray Sys Pump Anchors Revealed Nonconformance to Original Design & Same Condition Suspected to Exist for LPCI Sys Pump Anchors.Caused by Nonconforming Condition.Support Sys Modified
05000029/LER-1987-012, :on 870706,reactor Scram on High Main Coolant Pressure Occurred During Main Turbine Overspeed Trip Test. Caused by Personnel Error.Personnel Instructed on Need for Communications & Headphones Installed in Hall
05000259/LER-1987-015-01, :on 870709,reactor Protection Sys (RPS) Circuit Protector Tripped de-energizing RPS Bus a Causing RPS Half Scram.Caused by Mods Craftsmen Working Near Circuit Jarring Panel.Craftsmen Counseled
05000318/LER-1987-007-01, :on 871012,unplanned Actuation of Auxiliary Feedwater Actuation Sys (Afas) Experienced.Caused by Simultaneous Deenergization of Two Afas Sensor Cabinets. New Labels Made to Inform of Cabinet Locations
05000277/LER-1987-010-01, :on 870630,outboard Containment Isolation Valves Received Isolation Signals While RWCU Sys Isolation Control Relay Being Replaced.Caused by Inadequate Blocking Method.Involved Operators Counseled
05000424/LER-1987-043, :on 870628,improper Performance of Containment Pressure Surveillance Discovered.Caused by Personnel Error. Temporary Change to Procedure 1400-1 Incorporated Into Applicable Data Sheets
05000267/LER-1987-022, :on 870929,Loop I Shutdown Actuation Initiated by Plant Protective Sys (Pps).Caused by Failure of Logic Chip Z40 in PPS Module CS-1A1.Module Containing Failed Chip Replaced W/Operable Spare Module
05000259/LER-1987-024-01, :on 870930,unplanned RWCU Isolation Occurred. Caused by Degraded Electrical Connections on Temp Switch. Isolation Reset & Sys Returned to Svc.Connections on Temp Switch Repaired
05000341/LER-1987-024, :on 870625,plant Shut Down Due to Inoperabilty of Reactor Recirculation Sys Loop.Caused by Loss of Spring Pressure on Brush Due to Excessively Worn Brush.Increased Insp Frequency Implemented
05000312/LER-1987-043, :on 870924,improper Monitoring of New Effluent Release Point Occurred.On 871005,air Sample Cartridge Not Delivered for Analysis Due to Fan A-546 Being Off.Events Caused by Personnel Error.Air Samples Taken
05000334/LER-1989-002-01, :on 890213,reactor Trip Occurred Due to Feedwater Regulating Valve (MFRV) Malfunction.Caused by Failure of electro-pneumatic transducer.Electro-pneumatic Transducers for Valves Replaced
05000328/LER-1989-001-04, :on 890212,reactor Trip Signals Generated from Electromagnetic Interference When Spike Received on source- Range Channel N-31.Caused by Noise Induced Into Channel Cabling Due to Welding.Welding Suspended
05000296/LER-1987-003-04, :on 870918,RWCU Sys Isolated Unexpectedly During Troubleshooting Maint on Secondary Containment Isolation Damper.Cause Unknown.No Corrective Action Planned. Testing May Identify Corrective Actions Needed
05000440/LER-1987-044, :on 870624 & 28,RCIC Sys Automatically Isolated.Caused by Pressure Oscillations in Rcic/Leak Detection High Flow Instrument Process Lines.Leaking Transmitter Test Connection Repaired
05000213/LER-1987-008, :on 870625,control Rod 31 Dropped Into Core & Overfeed to Steam Generator 2 Occurred.Caused by Faulty Fuse & Inadequate Maint Procedure,Respectively.Fuse Replaced & Procedure Revised
05000286/LER-1989-001, :on 890204,initiated Safety Injection Via High Steam Flow Safety Injection Logic.Caused by Uneven Refilling of Steam Flow Instrumentation Lines.Safety Injecton Terminated & Plant Cooldown Proceeded
05000341/LER-1987-045, :on 870908,fuse Removed Resulting in Loss of Dc Control Power Causing Loss of Power Supply to Swing Bus & to LPCI Loop Selection Valves.Caused by Personnel Error.Dc Control Circuitry for Bus 72C Redesigned
05000282/LER-1987-009-01, :on 870618,safety Injection Pump 11 Did Not Start When Given Start Signal.Caused by Failure to Leave Ite Type 5HK250 4160V Breaker Completely Racked in & Lack of Specific Procedures for Racking Breakers
05000325/LER-1988-030, :on 881130,testing of Safety Relief Valves Revealed That 9 of 11 Valves Tested Lifted at Pressures Outside Tech Spec Tolerance of +/- 1%.Caused by Corrosion Induced Bonding of Pilot Valved Disc
05000293/LER-1989-004, :on 890127,discovered Two Primary Containment Air Operated Valves Inoperable Resulting in Unit Shutdown. Caused by Pressure Drop Rate of Stored Air Supply for Valves.New Tubing Installed
05000298/LER-1987-021, :on 840624,850503,24,0730 & 0816 Unplanned Actuations of Automatic Diesel Generators Occurred W/O Being Reported.Caused by Past Understanding of Term ESF Actuation as Applied to Diesel Generators
05000219/LER-1987-032, :on 870824,augmented Offgas Sys H2 Analyzer Not Calibr,Per Tech Spec.Caused by Personnel Error.Ler Will Be Required Reading for All Involved Depts to Stress Importance of Thorough Review of Plant Procedures
05000338/LER-1987-013, :on 870614,loss of Normal Power Supply to Emergency Bus Occurred During Testing.Caused by Failure to Follow Procedures.Electrical Maint Procedure Will Be Revised & Personnel Will Be Instructed
05000395/LER-1989-002, :on 890115,discovered That Scaffolding & Shielding Installations in East & West Penetration Rooms May Have Adverse Impact on Operability of safety-related Sys During Seismic Event.Caused by Personnel Error
05000369/LER-1989-001-03, :on 890117,failure to Take Compensatory Measures When Both Trains of Control Room Area Ventilation Were Inoperable.Caused by Lack of Attention to Detail by Planner a in Scheduling Pending Work Request
05000334/LER-1989-001-01, :on 890117,reactor Trip Due to Low Steam Generator Level Coincident W/Steam Flow - Feedwater Flow Mismatch.Caused by Operator Error.Operators Counseled Re Event
05000440/LER-1987-040, :on 870604,RCIC Sys Leak Detection High Steam Flow Trip Unit Noted to Be Reading Downscale.Caused by Steam Condensing in High Side Instrument Process Line of Associated Transmitter
05000369/LER-1988-005, :on 880323,spurious Train a Safety Injection & Main Steam Isolation Resulting in Reactor Trip Occurred. Cause Undetermined.Operations Personnel Implemented Procedure AP/1/A/5500/01
05000267/LER-1989-001, :on 890105,plant Protective Function Sys Loop Shutdown Function Unexpectedly Actuated,Causing High Primary Coolant Moisture Level.Caused by Leak in Core Support Floor Liner Cooling Tube
05000259/LER-1989-001-02, :on 890118 & 881209,determined That Seismic Documentation Could Not Be Established for Various Positions of 4,160-volt & 480-volt safety-related Circuit Breakers. Breakers Placed in Qualified Position
05000423/LER-1987-048, :on 871203 & 05,drain Hoses Discovered Strung Through Train B Recirculation Spray Sys Cubicle & Control Bldg Equipment Room Door,Respectively.Caused by Human Error. Memo to Reinforce Correct Methods Issued
05000440/LER-1987-059, :on 870821,RWCU Containment Isolation Occurred Due to Indicated High Differential Flow.Caused by Particulate Buildup in Flow Control Valve Positioner Air Flow Restriction Orifice
05000370/LER-1987-006-04, :on 870528,loss of Flow Alarm in Control Room for Containment Radiation Monitor Received.Containment Purge Sys Not Immediately Secured Due to Concern Over Possible Release of Unmonitored Containment Atmosphere
05000461/LER-1987-051, :on 870828,rod Pattern Control Sys,Rod Withdrawal Limiter High Power Setpoint Channel Functional Test Not Performed within 1 Hr Prior to Control Rod Movement in Mode 1.Caused by Personnel Error
05000325/LER-1987-018, :on 870502,loop Isolation Valve 1-E11-F024A Would Not Fully Close Against Sys Operating Pressure.Caused by Undersized Belleville Washer Spring Pack in Valve Operator.Washer Spring Packs Replaced
05000395/LER-1987-026, :on 871103,weekly Fire Svc Diesel Battery Test Exceeded Grace Period Allowed by Tech Spec Section 4.0.2. Caused by Personnel Error.Test Performed & Event Discussed During Maint Weekly Safety Meeting
05000424/LER-1987-031, :on 870603,while in Mode 3,steam Generator 2 Exceeded hi-hi Water Level Setpoint Resulting in Trip of Both Main Feedwater (MFW) Pumps & MFW Isolation.Caused by Procedural Error.New Max Level Established
05000250/LER-1986-034, :on 860921,during Performance of Secondary Plant Periodic Tests,Reactor Trip & Auxiliary Feedwater Actuation Occurred.Caused by Personnel error.Pre-amp for Source Range Neutron Flux Detector Replaced
05000318/LER-1986-007, :on 860912,reactor Manually Tripped Due to Partial Loss of Feedwater Flow to Steam Generator 21.Caused by Jumpering Across Two Terminals.Probes Rewired
05000529/LER-1986-046-01, :on 860922,safety Injection Actuation Signal Automatically Actuated.Caused by Malfunctioning of Channel B Manual Actuation Handswitch.Faulty Handswitch Replaced
05000341/LER-1986-028, :on 860915,inadvertent ESF Actuation of Isolation Valve Occurred During Testing.Probably Caused by Personnel Error Resulting from Test Lead Inadvertent Short Circuiting Across Relay Contacts
05000298/LER-1987-013, :on 870518,bus 4160V 1G Inadvertently Deenergized Due to Loss of Voltage During Transfer of Power from Startup to Normal Source.Cause Unknown.Investigation Conducted.No Furtherinvestigation Planned
05000338/LER-1986-018-01, :on 860915,w/unit in Hot Shutdown,Reactor Trip Breakers Opened When Individual Rod Position Indicators Determined Inoperable.Caused by Failed Transformer on Firing Card.Firing Card Replaced
05000325/LER-1986-030, :on 861120 & 1204,reactor Protection Sys Buses Deenergized on Units 2 & 1,respectively.Caused by Tripping of Motor Generator Set Output Breakers.Breaker Removed, Tested,Reinstalled & Returned to Svc
05000366/LER-1986-023-01, :on 860903,reactor Protection Sys Scram Occurred.Caused by Leaking Oil Filter Gasket Initiating Main Turbine trip.Electro-hydraulic Control Leak Repaired, Procedures Revised & Personnel Counseled
05000461/LER-1987-029, :on 870524,motor Driven Reactor Feed Pump Feedwater Regulating Valve 1FW004 Malfunctioned Causing High Water Level Transient.Caused by Failure of Regulating Valve. Mode Selector Switch Placed in Shutdown
05000298/LER-1987-011, :on 870517,while Conducting Monthly Turbine Valve Testing,Unplanned Actuation of Reactor Protection Sys & Containment Isolation Valve Groups 2,3 & 6 Initiated. Caused by Personnel Error.Procedure Revised
05000286/LER-1986-010-01, :on 860905,motor-operated Disconnect Switch on Generator Transmission Line Opened,Causing Turbine/Reactor Trip.Caused by Moisture in Underground Conduit Containing Control Wiring.New Conduit Installed
05000440/LER-1987-029, :on 870501,during Containment Venting,Operators Overrode Interlock to Maintain RCIC Suction Transfer W/O Reducing Suppression Pool,Violating Interlock Time Per Tech Spec.Operators Counseled.Design Change Planned
05000321/LER-1986-032, :on 860823,during Demonstration of Operability of LPCI Components,Lpci Injection Valve a Did Not Indicate Fully Closed.Caused by Failure to Correctly Assemble Valve Coupling.Vendor Manual Updated
05000298/LER-1986-016, :on 860813,reactor Scram Occurred.Caused by Lack of Proper Preplanning for Relay Replacement & Specific Procedural Guidance.Need for Preplanning of Maint Activities Reemphasized
05000416/LER-1986-040, :on 861027,determined That Two Weekly Surveillances of Breaker Alignment Not Performed in Required Tech Spec Time Interval.Caused by Nonlicensed Operator Oversight.Procedures Now Hand Carried
05000461/LER-1987-024, :on 870501,RWCU Sys Automatically Isolated Two Times Due to High Differential Flow Signal.Caused by Flow Perturbations Compounded by Error in Circuitry & Personnel Error.Sys Stabilized & Returned to Svc
05000321/LER-1987-008-01, :on 870422,reactor Scram & Partial Primary Containment Isolation Sys Group 2 Isolation Occurred.Caused by Procedure Inadequacy.Reactor Water Level Restored & Scram Signal Reset.Procedures Revised
05000251/LER-1986-023-01, :on 861025,operators Noted Loss of Ready to Start Light & Simultaneous Annunciation of Emergency Diesel Generator B Trouble Alarm.Caused by Low Lube Oil Temp Causing Shorting of Above Wire to Ground
05000414/LER-1986-045-01, :on 861011,turbine-driven Auxiliary Feedwater Pump Found to Be Inoperable from Standby Shutdown Facility. Caused by Incorrectly Installed Solenoid Valve Due to Design Deficiency.Valve Retubed
05000325/LER-1986-020, :on 860716 & 0806,hourly Fire Watches Performed Late.Caused by Inadequate Supervision & Detention in Control Bldg Elevator.Disciplinary Action Taken & Fire Watch Schedule Will Be Changed
05000321/LER-1986-003-01, :on 860128,high Drywell Pressure Signal Caused Several ESF Actuations to Occur During Hydrostatic/Pneumatic Test H-64.Caused by Personnel Error.Personnel Counseled & Incident Reviewed
05000306/LER-1986-004, :on 860801,electrician Opened Switch for Circuit 2 on Dc Panel 21 to Isolate Ground to Single Circuit,Causing Auxiliary Feedwater Pump to Start.Caused by Personnel Error.Personnel Counseled
05000369/LER-1986-019-02, :on 861014,failure to Perform Nuclear Svc Water Valve Stroke Timing Quarterly Periodic Test within Required Interval Discovered.Caused by Mgt Deficiency Due to Inadequate Administrative Controls
05000397/LER-1986-032, :on 861007,review of Plant Records Revealed That Control Rod Block intermediate-range Neutron Monitoring Quarterly Calibr Not Performed.Caused Insufficient Programmatic Controls.Items Now Tracked
05000281/LER-1986-014-02, :on 861010,results of Type C Containment Leakage Testing Indicated That Inside & Outside Containment Sump Trip Valves Had Leakage Greater than 300 Scfh.Caused by Erosion of Plug & Seat.Valves Will Be Replaced
05000528/LER-1986-062, :on 870211,discovered That Max Surveillance Interval for Monthly Functional Test of Plant Protection Sys (36ST-9SB02) Exceeded on 860222.Caused by Communication Error.Surveillance Program Enhanced
05000312/LER-1987-016, :on 870206,discovered That Cable Pulls Made Into safety-related Breaker Cubicle Cabinets for Both Trains of Emergency Electrical Power Left for Several Wks Causing Invalid Seismic Analysis.Caused by Const Error
05000316/LER-1986-022, :on 860710 & 11,two power-range Nuclear Instrumentation Ni Channels (N-41 & N-42) Inoperable Due to Personnel Failure to Properly Document & Control Drawing Error.Administrative Controls Strengthened
05000213/LER-1986-036, :on 860708,while Metering Charging Pump Out of Svc,Charging Pump a Taken Out of Svc Due to Broken Shaft. Caused by Metal Fatigue.Plant Placed in Hot Shutdown. Procedures Re Pumps Revised
05000260/LER-1986-010-02, :on 860702,sensitive Ultrasonic Exam Revealed Crack Indications in Recirculation Sys Reactor Vessel Inlet Nozzle Safe Ends.Corrective Action Proposals Await Development of Acceptance Criteria
05000251/LER-1987-003-01, :on 870127,process Radiation Monitor (PRM) R-12 Spiked High.Caused by Inability of Drawers to Filter Out Electrical Transients.Prm R-11 & R-12 Reset.Cause of Transients Evaluated
05000312/LER-1986-013, :on 860630,0706,22 & 23,CR/TSC Essential HVAC Sys a & B Autostarted.Incidents Part of Recurring Problems W/Design,Control & Operation of Cr/Tsc Essential HVAC Sys.W/
05000325/LER-1987-002-02, :on 870127,during Maint on Standby Gas Treatment (Sgbt) Train 1B,redundant Sgbt Train 1A Autostarted & Reactor Bldg Ventilation Sys Automatically Isolated.Caused by Inadequate Procedure
05000341/LER-1987-001, :on 870126,during Calibr Activities in RWCU Sys,Esf Isolation Actuation Received.Caused by Inadequate Communication Between Instrument Repairman & Shift Personnel.Personnel Counseled
05000220/LER-1986-015, :on 860530,reactor Scram Occurred,Initiating Reactor Bldg Emergency Ventilation.Caused by Lifted Neutral Leg of Output Protective Relaying Circuit.Lifted Lead Replaced & Reactor Scram Reset
05000315/LER-1986-002, :on 860217,discovered That Three Reactor Trip Sys Interlock Setpoints Not Set Per Tech Spec Requirements. Caused by Misinterpretation of Tech Specs.Procedures Revised to Agree W/Tech Specs
05000263/LER-1986-014, :on 860515,reactor Protection Sys Trip Occurred.Caused by Noise Spike on Intermediate power- Range Monitor 14 Tripping Channel a of Reactor Protection Sys.Channel a Trip Reset
05000280/LER-1986-029, :on 860929,svc Water to Charging Pump Svc Water Subsystem Lost.Caused by Leak on Blowdown Line for in-line Strainer.Line Repaired
05000529/LER-1986-046, :on 860922,inadvertent Safety Injection Actuation Signal Automatically Actuated.Caused When One Channel of Manual Trip Path Test Actuated & Second Channel Handswitch Malfunctioned.Handswitch Replaced
05000312/LER-1987-005, :on 870113,condensate Storage Tank Level Instrument Used to Determine Auxiliary Feedwater Pump Capacities During Periodic Surveillance Testing Not Adequately Calibr.Cause Not Stated
05000528/LER-1986-053, :on 860911,reactor Tripped on Low Steam Generator Pressure.Caused by Procedural Inadequacy Re Use of Circuit Card Extender Board During Maint.Notice Distributed & Procedures Revised
05000263/LER-1986-011, :on 860509,EFT Sys (Control Room HVAC) Automatically Transferred to Toxic Chemical Mode Due to Hydrogen Chloride Monitor Tape Break.Caused by Small Imperfection on Tape
05000409/LER-1986-029, :on 860918,reactor Scrammed on Low Recirculation Flow When Forced Circulation Pump 1B Tripped. Caused by Closed Seal Inject Supply Valve.Valve Controller Rebuilt & Procedure Change Implemented
05000483/LER-1986-034, :on 860908,pre-action Sprinkler Sys Protecting Cable Trays of Auxiliary Bldg Inoperable W/O Continuous Fire Watch.Caused by Personnel Error.Design & Annunciator Response Procedure Evaluated
05000251/LER-1986-017-01, :on 860809,auxiliary Feedwater Flow Initiated Following Testing of Automatic Feedwater Sys.Caused by Personnel Error.Operator Counseled & Procedure AP-103.16 Re Technical Advisor Duties Revised
05000250/LER-1987-004, :on 870112,discovered That One Train of Auxiliary Feedwater Out of Svc When Both Units Above Hot Shutdown.Caused by Erroneous Flow Indication of Indicator FI-1457A.Flow Transmitter Replaced
05000250/LER-1987-003, :on 870112,annunciator E 8/3 Generator Field Ground Alarmed.Caused by Turbine Plant Cooling Water Leak in Exciter Housing.Leaking Exciter Air Cooler Isolated & Drained
05000331/LER-1987-001, :on 870114,RWCU Sys Isolated on Signal from F Temp Differential Switch.Caused by Steam Leak in Root Isolation Valve.Corrective Maint Action Request Generated to Repack Root Valve & Investigate Leak
05000414/LER-1986-009-01, :on 860424,steam Generator Level Channel, Which Was Out of Calibr,Not Placed in Tripped Position within Specified Time Frame.Caused by Personnel Error. Shift Supervisor Counseled
05000529/LER-1986-039-01, :on 860903,control Room Essential Filtration Actuation Signal (CREFAS) Generated After CREFAS Module Removed from Bypass Before All Trip Inputs Cleared. Appropriate Disciplinary Action Taken
05000482/LER-1986-009, :on 860224,control Room Ventilation Isolation Signal Initiated Due to Loss of Sample Flow in Intake Radiation Monitors GK-RE-04 & GK-RE-05.Cause Unknown. Evaluation Continuing.Monitors Returned to Svc
05000346/LER-1986-037, :on 860812,Teledyne Assumptions for Bechtel Analyses of Makeup & Purification Sys Inlet to Letdown Coolers Inconsistent W/Normal Plant Operating Conditions. Assumptions Will Be Included in Procedures
05000370/LER-1986-016-02, :on 860812,main Supply Breaker to 125-volt Dc Vital Instrumentation & Control Power Distribution Ctr Accidentally Bumped Open,Causing Reactor Trip.Caused by Personnel Error.Protective Covers Installed
05000382/LER-1986-017, :on 860811,chemistry Technicians Failed to Sample Proper Gas Decay Tank.Caused by Operations Personnel Realigning Inservice Tanks W/O Informing Chemistry Technicians.Procedure Revised
05000321/LER-1986-033, :on 860806,reactor Protection Sys Bus a Lost Because Motor Generator a Set Output Breaker Tripped.Caused by Failure of Motor Generator Set Overvoltage Relay 1C71-K751A.Relay Replaced
05000321/LER-1986-030, :on 860802,main Turbine & Reactor Feedwater Pumps Tripped Due to Feedwater Flow Oscillations.Caused by Opening of Min Flow Bypass Valves Due to Setpoint Error. Procedure Revised & Instruments Calibr
05000440/LER-1986-046, :on 860813 & 14,independent Sample Analysis & Release Rate Calculation/Discharge Line Valving Verifications Not Performed Prior to Commencing Liquid Radwaste Batch Discharge Releases.Caused by Personnel Error
05000424/LER-1987-010, :on 870321 & 24,reactor Protection Sys Actuations Occurred.Caused by Initial Adjustments of Automatic Controllers for Steam Dump & Bypass Feedwater Regulating Valve Controllers.Controls Adjusted
05000237/LER-1987-001-01, :on 870102 & 0121,ultrasonic Testing Revealed Through Wall Indications on Pipe Welds PD5-D20 & 8-12.Caused by Igscc.Engineering Evaluation on Indications Performed
05000341/LER-1987-009, :on 870325,RHR Pump C Tripped Due to Inboard Isolation Valve Closing.Caused by Intermittent Failure of Master Trip Unit.Futher Investigation of Master Trip Unit Will Be Made by Mfg.Isolation Logic Reset
05000341/LER-1986-017, :on 860624,discovered That Emergency Equipment Cooling Water Sys Capacity Inadequate to Remove Drywell Cooler Heat Loads During Small Break Inside Drywell W/O Degrading Performance.Design Change Issued
05000322/LER-1986-026, :on 860703,automatic Initiation of Reactor Bldg Standby Ventilation Sys a Side Occurred.Caused by Technician Dropping Screwdriver in Panel & Deenergizing Relay During Surveillance Test.Test Procedure Revised
05000409/LER-1986-019, :on 860627,reactor Scrammed on High Power/ Recirculation Flow Signal.Caused by Improper Setting of Linkage Control to Reactor Feedwater Pump 1B.Linkage Readjusted & New Procedure Written
05000282/LER-1986-009-01, :on 861205,audit Determined That Refueling Water Storage Tank Outlet Valves MV-32098 & MV-32099 Not Tested Monthly.Caused by Misinterpretation of Tech Specs. Tech Specs Clarified
05000370/LER-1986-009-04, :on 860623,ESF Train a Feedwater Isolation Signal Actuated During Reactor Trip Breaker Testing.Caused by Defective Procedure.Isolation Valves Reopened.Procedures Will Be Revised.Personnel Will Review Event
05000529/LER-1986-037-01, :on 860626,main Steam Line Isolation Signal Actuated Due to Steam Generator 1 Level Swell.Caused by Cognitive Operator Error.Operator Counseled
05000213/LER-1986-026, :on 860622,while in Mode 1,reactor Trip Occurred When Power Increased Above 10%.Caused by Ceiling Tile Stuck in Relay,Causing RCS Low Flow Indication.Debris Removed & Scram Circuits Tested
05000400/LER-1986-008-03, :on 861206,digital Rod Position Indication Sys Not Operable During Power Ascension Test.Caused by Failure to Review Procedure Against Requirements of Tech Spec Special Test Exception 3.10.5
05000249/LER-1986-008-08, :on 860618,Group II Primary Containment Isolation Received,Causing Isolation of Reactor Bldg Ventilation & Start of Standby Gas Treatment Sys.Caused by Personnel Error.Personnel Cautioned Re Maint
05000213/LER-1986-030, :on 860627,during Operation in Mode 1,dropped rod-load Runback Signal Generated Spuriously on Channel 34 of Nuclear Instrumentation Sys.No Rod Motion in Progress. Cause Not Yet Defined.Sys Will Be Replaced
05000281/LER-1986-007-02, :on 860617,reactor Trip Occurred Due to High Level in Steam Generator A.Caused by Failure of Valve FCV-2478 to Close Due to Metal Debris Between Plug & Valve Seat.Metal Debris Removed & Valve Reassembled
05000335/LER-1986-007-03, :on 860804,4,160-volt Bus 1A3 Deenergized Due to Inadvertent Actuation of Differential Current Protective Relay.Caused by Technician Failure to Ensure Breaker Cubicle Door Fully Open While Inserting Breaker
05000220/LER-1986-024, :on 860803,turbine Trip & Subsequent Scram Occurred.Caused by Increase in Reactor Water Level.Hpci Mode of Feedwater Reset,Reactor Water Level Restored & Instrument & Control Personnel Notified to Remove Signal
05000423/LER-1987-012, :on 870320,Tech Spec Surveillance on Snubber Visual Insp Missed.Caused by Engineering Oversight & Outdated Snubber List.List Updated & All Snubbers Inspected
05000341/LER-1986-021, :on 860720,while in Cold Shutdown,Rwcu Inboard Isolation Valve Autoisolated Three Times.Caused by Blown Fuses & Broken Differential Temp Thermocouple Flange.Fuses Replaced
05000245/LER-1986-019-01, :on 860531,automatic Initiation of Standby Gas Treatment Sys Occurred as Result of Steam Tunnel Ventilation Radiation Monitor Trip.Caused by Radiation Monitor Out of Adjustment.Calibr Procedure Revised
05000237/LER-1986-011-05, :on 860520 Full Scram Occurred Twice Due to Low Reactor Water Level.Caused by Reactor Feedwater Regulating Valve B Booster Relay Failure & Personnel Error.Relay Replaced & Violation Rept Completed
05000461/LER-1987-011, :on 870310 & 11,shifting of Main Control Room Ventilation Sys to High Chlorine Mode Occurred.Caused by Exceeding Trip Setpoint.Mods to Raise Alarm Setpoint on Chlorine Detectors Planned
05000461/LER-1987-010, :on 870308,main Control Room Ventilation Sys Train a Shifted to High Chlorine Mode on Signal from Chlorine Detector OXE-VC018B.Caused by Discolored Chlorine Sensitive Tape.Maint Work Request Written
05000213/LER-1986-023, :on 860518,nuclear Instrumentation power-range Channel 34 Spuriously Generated Dropped rod-load Runback Signal.Caused by Load Limiter Mechanically Binding.Load Limiter Clutch Adjusted
05000280/LER-1986-014, :on 860511,temporary Degradation of Dc Bus Voltage B Experienced,Resulting in ESF Actuation.Caused by Inadequate Procedure in Design Change to Replace Batteries. Procedure Will Be Revised
05000327/LER-1986-019, :on 860505,auxiliary Bldg Ventilation Isolation Occurred While Mod to 400-volt Shutdown Board 1A1-A Performed.Caused by Personnel Error Causing Loss of Power to Radiation Monitor & Subsequent Spike
05000423/LER-1988-023, :on 881006,MSIV Closed During Performance of Partial Stroke Surveillance Test,Resulting in Reactor Trip Due to Low Level in Steam Generator.Caused by Procedural Inadequacy.Surveillance Procedure Changed
05000400/LER-1987-008, :on 870227,loss of Main Feedwater & Automatic Start of Both motor-driven Auxiliary Feedwater Pumps Occurred.Caused by Transient in Turbine Load.Motor Replaced & Tested & Valve Returned to Svc
05000423/LER-1986-023, :on 860311,inappropriate Calibr Method Used & on 860312,monitors Calibr Nonconservatively.Caused by Defective Procedure.Calibr Methods for Radiation Monitors Reviewed & Four Monitors Recalibr
05000483/LER-1985-054, :on 851226,reactor Trip Occurred.Caused by Spurious Trip Generated by Loop 1 Over Temp Delta Temp Instrumentation.Circuit Card Generating Signal Replaced
05000249/LER-1987-002-09, :on 870225,while Unit Operating at 87% Power, HPCI Sys Discovered Inoperable.Caused by Oil Pressure Regulation Valve Failure.Similar Event Occurred on 870313. Limits of PS4 Reset to 60 Psig Increasing
05000352/LER-1987-006, :on 870218 & 19,control Room Ventilation Sys Isolated & Control Room Emergency Fresh Air Supply Sys Train B Initiated.Caused by Chlorine Analyzer D Falsely Indicating Chlorine Present.Ventilation Isolation Reset
05000413/LER-1985-020, :on 850314,reactor Trip Occurred Due to Power Range High Flux Rate Signal.Caused by Loose Detector Cable Inside Power Range Cabinets.Work Request Initiated to Repair Loose Cable
05000327/LER-1986-028, :on 860702,discovered Failure to Comply W/Asme Section XI Accuracy & Range Requirements for Instruments Used for Pump Testing.Caused by Personnel Error.Instruments Calibr to Required Accuracy
05000320/LER-1986-007-02, :on 860727,grab Sample Not Taken & Analyzed within Tech Spec Limit of 24 H.Caused by Declaring Epicor II Ventilation Sys Monitor Inoperable on 860724.Another Grab Sample Obtained
05000483/LER-1986-008, :on 860403,control Room Emergency Ventilation Sys Train a Discovered Inoperable Since 860318.Caused by Procedural Deficiencies & Personnel Error.Procedures Revised & Personnel Reminded of Tech Spec Requirements
05000272/LER-1986-011-01, :on 860627,continuous Fire Watch Not Maintained for Inoperable Fire Door,Contrary to Tech Specs.Caused by Personnel Error.Hourly Fire Watch Posted & Info Directive AP-25 Will Be Issued
05000250/LER-1986-030, :on 860627,reactor Trip & Subsequent Safety Injection Actuation Occurred,Due to Personnel Performing Sections of Operating Procedure 14004.1.Caused by Personnel Error.Affected Procedure Revised
05000341/LER-1986-003, :on 860311,during Surveillance Test of Div II Isolation Logic,Rwcu Sys Isolated.Caused by Repairman Incorrectly Lifting Thermocouple Lead in Div I Isolation Logic.Personnel Counseled
05000213/LER-1986-028, :on 860610,switchgear Room Halon Sys Declared Inoperable.Caused by Failure to Perform Adequate Retest of Sys Mod & Document Basis for Test Waiver.Continuous Fire Watch Posted
05000344/LER-1986-006, :on 860605-06 & 10,sodium Hydroxide Additive Flowrate Inadequate.Caused by Repeatability Problem in Establishing Ref Position of Kerotest Globe Valves.Valve Internals Replaced
05000213/LER-1986-024, :on 860609,at 100% Power,Dropped Rod Turbine Load Runback Initiated.Caused by Spurious Signal in Power Range 34.Load Runback Reset Manually & Power Range Channels Will Be Replaced
05000528/LER-1986-041, :on 860614 & 0531,channel Check on Radiation Monitor Missed.Radiation Protection Technicians Counseled on Verbatim Compliance W/Approved Procedures.Caution Also Added to Applicable Procedure
05000245/LER-1986-005, :on 860205 & 0521,reactor Scrammed on APRM Hi Hi Flux.Caused by Malfunction of Mechanical Pressure Regulator Sys.Mechanical Regulation Sys Adjusted to Optimize Performance.Complete Overall of Sys Planned
05000328/LER-1986-003-05, :on 860530,spurious Spikes on Radiation Monitors Caused Two Containment Ventilation Isolations. Caused by Loose Alarm Circuit Wire & Electromagnetic Interference.Wire Tightened
05000373/LER-1986-022-02, :on 860612,RHR Shutdown Cooling Isolation Occurred During Performance of LES-PC-107.Caused by Operator Error.Operator Counseled on Unacceptability of Actions & Need for Attention to Details
05000213/LER-1986-019, :on 860506,tube in Steam Generator 2 Not Plugged.Caused by Typo in Procedure & Inadequate Review Process.Procedure Sur 5.7-82 Will Be Revised to Include Signed Double Verification
05000259/LER-1986-015-01, :on 860424 & 29,during Installation of Permanent Switch Protective Covers on Reactor Protection Sys (RPS) MG Panel Switches,Rps Trip Occurred.Caused by Accidental Bump of Control Switch
05000311/LER-1986-003-02, :on 860502,safety Injection Occurred,Resulting in Reactor Trip.Caused by High Steam Flow Coincident W/Low Average Reactor Coolant Temp (Tave).Operating Procedures Revised to Ensure Tave within Programmed Band
05000409/LER-1986-015, :on 860506,while Reactor Shut Down,Spike Occurred on Nuclear Instrumentation Channel 6,generating Scram Signal.Caused by Burned Out Filament in Tube in Positive High Voltage Power Supply
05000414/LER-1986-010-01, :on 860426,steam Generator 2A Channel 3 Level Indicator Pegged High Causing Steam Generator hi-hi Level Alarm Actuation.Caused by Vent Valve on Ref Leg of Level Transmitter leaking-by.Indicator Repaired
05000237/LER-1985-037-03, :on 851007,reactor Bldg Ventilation Tripped & Isolated W/Standby Gas Treatment Sys Autostarting as Required.Caused by Operator Removing Wrong Fuse.Station Tailgate Session Conducted
05000321/LER-1986-020, :on 860425,RWCU Sys Inboard & Outboard Primary Containment Isolation Valves 2G31-F001 & 2G31-F004 Isolated on High Leakage Flow Signal.Caused by Disconnected Jumper During Functional Test.Isolation Reset
05000280/LER-1986-028, :on 860925,individual Rod Position Indicators for All Control Rods Moved Down Approx 25 Steps.Caused by Failed Normal Negative Power Supply.Two Negative Power Supplies Replaced & Calibr
05000440/LER-1988-020, :on 880605,reactor Scram Occurred Due to High APRM Neutron Flux Levels.Caused by Personnel Error.Automatic Mode of Flux Control Disabled Until Adjustments Completed & Personnel Involved Disciplined
05000285/LER-1988-011, :on 880327,containment Integrity Lost Because Swagelok Cap on PC-743 Test Tee Removed for Leak Rate Testing Not Reinstalled Until Discovered on 880419.Caused by Inadequate Procedure.Procedure Upgraded
05000338/LER-1988-005, :on 880113,turbine Trip,Reactor Trip & Main Feedwater Isolation Occurred.Caused by hi-hi Level in Steam Generator Which Resulted from Generator Level Oscillations. Main & Auxiliary Feedwater Secured & Restored
05000348/LER-1988-016, :on 880525,fire Door 408 Inoperable for More than 7 Days.Caused by Damage on Door Secured in Open Position to Facilitate Access While Doing Work in Area.Door Repaired & Returned to Functional Status
05000321/LER-1988-009-02, :on 880520,reactor Scram Occurred When Three MSIVs Less than 90% Opened.Caused by Procedure Deficiency. Nitrogen to MSIVs Restored,Plant Procedures Temporarily Revised & Permanent Revs Scheduled
05000440/LER-1986-008, :on 860430,containment Fire Hose Reel Inboard/ Outboard Supply Isolation Valves Discovered in Open Position.Valves Opened Before Start of Core Alterations on 860321 by Shift Operators.Personnel Counseled
05000327/LER-1986-006-01, :on 860318,roving Fire Watch Person Unable to Enter Two Rooms to Check for Fires Due to Inoperable Fire Doors.Caused by Loose Screw in Pull Handle.Door Repaired & Returned to Svc
05000483/LER-1986-015, :on 860423,auxiliary Feedwater Actuation Sys & Steam Generator Blowdown Isolation Occurred.Caused by Radwaste Technician Unintentionally Opening Dc Fused Disconnect Switch.Incident Reviewed W/Staff
05000341/LER-1988-020, :on 880508,incorrect HPCI Surveillance Test Procedure Performed Causing Reactor Scram.Procedure Intended to Be Performed in Cold Shutdown or Refueling Condition. Procedure 24.202.04 Revised
05000414/LER-1988-017-01, :on 880424,main Feedwater Isolation Occurred Due to hi-hi Level Turbine Trip Signal from Steam Generator. Caused by Personnel Error.Steam Generator Levels Brought Under Control Using Auxiliary Feedwater
05000293/LER-1988-012, :on 880425,automatic Start of Loop a Reactor Bldg Closed Cooling Water Sys Pump a Occurred.Caused by Accelerated Wear Induced Failure of Coupling in Pump B. Failed Coupling Replaced & Addl Measures Taken
05000293/LER-1988-013, :on 880425,inadvertent Manual Start of Emergency Diesel Generator (EDG) B Occurred.Caused by Personnel Error.Improvements to Local Control Panel to EDG Identified & Tracked
05000370/LER-1988-008-03, :on 880731,steam Generator Main Feedwater Regulating Valve Failed in Closed Position & Reactor Manually Tripped.Caused by Personnel Error.Broken Wire on Valve 2CFSV0320 Repaired
05000321/LER-1988-005-02, :on 880419,reactor Scram Occurred After Personnel Exchanged Turbine Lubrication Oil Coolers.Caused by Personnel Error.Involved Operations Personnel Counseled & Procedures Revised
05000482/LER-1988-014, :on 880821,ESFAS Auxiliary Feedwater Pump Low Suction Pressure Instrumentation Channel Check Procedure Found Not to Meet Tech Spec 4.3.2.1 Requirements.Caused by Contractor & Personnel Error.Procedure Changed
05000352/LER-1988-015, :on 880418,emergency Diesel Generator auto-started Due to Unplanned Test Start Signal.Caused by Personnel Error.Training Memo Issued to All Field Engineers Requiring Completion of Stated Form
05000312/LER-1988-006, :on 880414,potential Deviation from Quality Initiated to Rept Spurious Actuations of Control Room Technical Support Ctr Essential HVAC Sys.Caused by High Temp Indications.Temp Switch Changed
05000328/LER-1988-019, :on 880407,inadequate Work Control Caused ECCS Pumps to Be Inoperable Resulting in Inadvertent Entry Into Tech Spec 3.0.3.Plant Procedure Revised to Ensure Activities Controlled During Work Impact Evaluation
05000280/LER-1986-001-01, :on 860107,reactor Trip Occurred Due to Loss of Instrument Air.Caused by Hot Gas Bypass Valve in Dryer Improperly Adjusted to Maintain Air Temp Above Freezing. Operator Attempted to Gain Manual Control
05000263/LER-1986-002, :on 860107,during HPCI Sys Monthly Surveillance Test,Hpci Pump Flow Controller Would Not Respond in Auto Mode.Caused by Switch Contacts Prohibiting Reading of Setpoint.Switch Mechanisms Cleaned
05000324/LER-1988-008-02, :on 880331,full Reactor Protection Sys Trip Occurred When Mode Switch of APRM Rotated Beyond Switch Mechanical Stop Position.Caused by Improperly Configured Switch.Switch Replaced
05000341/LER-1988-023, :on 880528 & 0713,RWCU Sys Manually Isolated by Operator Action.Caused by Separate Instrument Line Compression Failures.Instrument Lines Repaired & RWCU Sys Operating Procedures Revised
05000259/LER-1986-024, :on 860822,determined That nonsafety-related Piping Sys Penetrating Reactor bldg-turbine Bldg Wall Not Seismically Qualified.Caused by Design Oversight.Util Will Demonstrate Plant Qualification
05000529/LER-1985-006-01, :on 851231,while in Mode 6,containment Purge Isolation Signal & Control Room Emergency Filtration Actuation Signal Received on Both Channels.Caused by Improper Reset by Operator.Operator Counseled
05000213/LER-1986-001, :on 860107 & 12,discovered That Two Tech Spec Fire Doors Inoperable.Caused by Contractor Personnel Error. All Plant & Contractor Personnel Reinstructed in Station Procedures & Regulations
05000413/LER-1988-021-01, :on 880623,fire Protection Console Operator Erroneously Initiated Hourly Firewatch for Interior Doghouse.Caused by Inaccurate Info on Fire Protection Graphic Display.Firewatch Reestablished
05000414/LER-1988-024, :on 880622,turbine Driven Auxiliary Feedwater Pump Automatic Start Due to Loss of Alternate Control Power. Cause Undetermined.Procedure Changes Implemented
05000325/LER-1988-015-01, :on 880612,control Bldg Emergency Air Filtration & HVAC Sys Automatically Isolated Due to Actuation of Chlorine Detector in Tank Car Storage Area. Cause Undetermined
05000334/LER-1988-003-01, :on 880225,inadvertent Start of Auxiliary Feedwater Pump Occurred.Caused by Procedural Deficiency in Surveillance Test.Procedure Revised to Transfer Steam Inlet Valve Control W/Valves Open
05000370/LER-1988-002-04, :on 880527,both Trains of Annulus Ventilation Sys Became Inoperable During Shutdown Activity.Caused by Deficient Communication Among Work Groups.Rept Will Be Reviewed W/Personnel
05000327/LER-1987-006-01, :on 870124,operation of All Equipment Affected by Safety Injection Test Signal Not Verified.Caused by Deficient Surveillance Instructions SI-26.1A & SI-26.2A. SI-26.1A & SI-26.2A Revised
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
05000328/LER-1988-001-01, :on 880111,ltr Received from S&W Revealing That Lower Support Frame of Containment Spray HXs 2A & 2B Could Be Overstressed During Design Basis Seismic Event.Caused by Design Deficiency.Frames Modified
05000370/LER-1987-021-02, :on 871130,reactor Trip Occurred.Caused by Reversed Wiring on Generator Stator Cooling Differential Pressure (D/P) Switch Circuitry Combined W/Calibr Drift of D/P Switch & Gauge.Wiring Will Be Corrected
05000483/LER-1988-002, :on 880107,two RHR Trains Rendered Inoperable When Operator Inadvertently Closed cross-connect Valve. Caused by Control Switches Being in Close Proximity to Each Other.Control Switches Covered W/Plastic
05000412/LER-1988-001, :on 880105,refueling Water Storage Tank Level Indicators Declared Inoperable When Instruments Failed to lo-lo Position.Caused by Sensing Lines Freezing.Design Changes Implemented
05000344/LER-1987-037, :on 871206,reactor Tripped Manually Following Load Rejection Transient.Caused by Failure of Load Decrease Pushbutton in Electrohydraulic Control Sys.Load Decrease Pushbutton Replaced
05000328/LER-1988-005, :on 880212,smoke Discovered Coming from Speed Increaser Unit for Centrifugal Charging Pump 2A-A.Caused by Bolts Backing Out Due to Lack of Periodic Adjustments.Speed Increaser Lube Oil Pump 2A-A CCP Replaced
05000414/LER-1988-010-01, :on 880203,during NRC Equipment Qualification Insp,Damaged RHR Sys Rotork Electric Motor Operated Valve Actuator Discovered.Caused by Improper Installation of Motor to Actuator on Valve 2ND2A.Valve Repaired
05000324/LER-1988-004-02, :on 880224,standby Gas Treatment Sys Trains 2A & 2B Autostarted & Reactor Bldg Ventilation Autoisolated. Caused by Blown Power Supply Fuse in Div I Trouble/Start Relay Logic Circuitry.Fuse Replaced
05000293/LER-1988-004, :on 880202,unplanned Automatic Actuations of Portions of Primary Containment & Reactor Bldg Isolation Control Sys Occurred.Caused by Inadequate Instructions. Sys Restored to Svc.Instructions Revised
05000293/LER-1987-018, :on 871123,24 & 26,automatic Actuations in RWCU Sys Portion of Primary Containment Isolation Control Sys Occurred.Caused by Partially Clogged Pressure Gauge Snubbers & Failed Coil
05000316/LER-1985-005, :on 850130,one Cell on Train AB Battery Had Unacceptable Specific Gravity Reading.Cell Replacement Completed & Cross Tie Breaker Opened Restoring Both Dc Bus Trains
05000247/LER-1986-009, :on 860315,LPSI Setpoint Found Out of Spec. Review of Cause Continuing.Instruments Calibr on 860315. Calibr Confirmed on 860319
05000324/LER-1986-004-02, :on 860303,primary Containment Group 6 Isolation,Automatic Isolation of Reactor Bldg Vent Sys & Automatic Start of Standby Gas Treatment Sys Occurred. Caused by Blown Fuse F-5.Fuse Replaced
05000366/LER-1985-037-01, :on 851218,during Surveillance Procedure 57SV-E41-003-2,RCIC Outboard Primary Containment Isolation Valve 2E51-F008 Isolated.Caused by Personnel Error. Personnel Disciplined & Valve Reopened
05000327/LER-1986-005-01, :on 860218,0301 & 05,fire Watch Could Not Enter Applicable Rooms to Check for Fires Due to Inoperable Fire Doors.Caused by Faulty Screw.On 860303,fire Watch Not Initiated Due to Personnel Error
05000250/LER-1985-031, :on 851007,w/unit at 100% Power,Turbine Runback to Approx 540 Mwe Occurred.Caused by Failure of RPI Inverter Due to Positive Dc Spike Coming from 3AR2 Relay Coil.Fuses & Relay Coil Replaced
05000387/LER-1984-044, :on 840613,average Rod Scram Insertion Time Required by Tech Spec 3.1.3.4 Not Met for All Rods. Apparently Caused by Poor Control Rod Scram Pilot Valve Performance.Valves Modified
05000220/LER-1985-018, :on 851010,low Air Pressure Start Test of Tech Spec Section 4.6.7.b.4 Failed.Caused by Need to Energize or Manually Bypass Solenoids on Governor Sys.Mods to Governor Sys & Sys Manual Start Performed
05000312/LER-1985-021, :on 851119,emergency Diesel Generator a Automatically Started When Bus 4A Normal Supply Breaker Tripped on Overvoltage Condition.Caused by Technicians Disconnecting Ground Wiring
05000483/LER-1985-050, :on 851127,control Room Ventilation Isolation & Containment Purge Isolation Signal Occurred.Caused by Failed Microprocessor Fuse for Radiation Monitor & Tripped Breaker.Fuse Replaced & Breaker Closed
05000320/LER-1984-017, :on 841024,sonar Insp of Flood Protection Dike Revealed Degradation of Submerged Toe in Vicinity of River Water Pump Houses.Sept 1985 Insp Revealed Same Degradation. Baseline Degradation Criteria Changed
05000361/LER-1985-039, :on 850722,toxic Gas Isolation Sys Train B Actuated When Hydrocarbon Analyzer Malfunctioned.Control Room Emergency Air Cleanup Sys Actuated as Required.Toxic Gas Isolation Sys Reset
05000249/LER-1985-020-05, :on 850925,no Particulate Sample for Reactor Bldg Ventilation Sys Collected for Wk.Caused by Failure to Replace Screen in Filter Holder After Last Sample.Signs to Be Posted in Future
05000341/LER-1985-076, :on 851109,emergency Diesel Generator 11 Auto Start Did Not Clear & Generator Would Not Shut Down During Dedicated Shutdown Sys Test.Caused by Misconfigured Contacts in Auxiliary Switch
05000416/LER-1985-037, :on 850620,smoke Detector in Control Bldg HVAC Chase Failed to Annunciate on Control Room Console During Routine Testing.Caused by Erroneous Zone Description Entry Onto Data Base.Controls Re Data Mod Underway
05000316/LER-1985-038-01, :on 851110,ESF Actuation Occurred Due to Lower Containment Airborne Monitor Particulate Channel Train B High Alarm.Caused by Error in Inputing High Alarm Setpoint Exponent Value.Technician Counseled
05000315/LER-1985-054, :on 851026,w/unit in Mode 3,ESF Actuation Signal Received from Steam Generator 11 hi-hi Level.Caused by Inadvertent Overfill of Generator.Level Returned to Normal.Operator Counseled
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
05000409/LER-1985-019, :on 851026,partial Reactor Scram Occurred Due to Momentary Short in CRD Gas Pressure Circuit.Caused by Worn Mechanical Seal Allowing More Seal Water to Flow Through than Normal.Seal Leakage Reduced
05000312/LER-1984-016, :on 840425,RCS Pump Seal Return Line Isolation Valve Exceeded Tech Spec Stroke Time Limit.Caused by Weaknesses in Documentation & Surveillances of Equipment. Valve Restroked.Surveillance Procedure Revised
05000483/LER-1985-052, :on 851209,reactor Tripped Twice Due to Water Level in Steam Generators Reaching lo-lo Level Trip Setpoint.Caused by MSIV Fast Closure Due to Circuit Card Failure.Circuit Card Replaced
05000298/LER-1985-020, :on 850810,surveillance Testing on Automatic Depressurization Sys Improperly Conducted.Caused by Personnel Error & Lack of Procedures Re Design Change 84-01. Procedures Revised & Personnel Counseled
05000362/LER-1984-038-01, :on 840922,power Reduction from 100% Power Initiated to Perform Scheduled Surveillances & Maint Items. Caused by Iodine Spiking.Primary Coolant Activity Monitored
05000315/LER-1985-031, :on 850709,RHR Sys Local Flow Measurements Did Not Coincide W/Process Instrumentation Installed in Safety Injection Path.Similar Discrepancy Discovered on 850715 Re RHR Cooldown Flow Indication
05000366/LER-1985-028-01, :on 850809 & 12 During line-by-line Review of Tech Specs & Implementing Procedures,Personnel Noted Three Surveillance Requirements for high-range Radiation Recorder Not Satisfied After Addition of Amends
05000483/LER-1985-003, :on 850115-24,spurious Control Room Ventilation Isolation Signals Occurred.Caused by Incompatibility Between Software & Hardware in Microprocessing Unit for Radiation Monitor.Necessary Hardware Installed
05000370/LER-1984-032-01, :on 841207,Westinghouse Notified Util of CRD Mechanism Fabrication Error.Caused by Loose Guide Screw. Drive Mechanisms Inspected & Repaired as Necessary During Outage
05000483/LER-1985-034, :on 850718,trip Occurred as Result of Power Range High Negative Flux Rate Signal.Caused by Inadequate Cooling of Rod Drive Power Cabinet.Caution Tag Added to Handswitch Controlling Room Cooler
05000275/LER-1985-002-01, :on 850719,while Restoring Train a to Svc, Inadvertent Actuation of Train B Safety Injection Occurred. Caused by Operator Inadvertently Moving Reset Block Switch Instead of Block Position
05000370/LER-1985-019-02, :on 850712,main Generator Tripped When Both Channels of Generator X Phase Differential Current Protective Divices Actuated.Caused by Component Failure. Damage Repaired & Equipment Monitored
05000315/LER-1985-047, :on 850916,listed Equipment Not Calibr at Tech Spec Required Frequency.Caused by Not Including Instruments in Plant Nuclear Test Schedule.Calibr Completed & Added to Schedule
05000259/LER-1985-030, :on 850705,deficiency Found in Testing Requirements for Primary Containment Isolation Valves 1-55 & 1-56.Caused by Tech Specs Not Being Revised.Status of Valves Changed to Normally Open
05000328/LER-1984-020, :on 841216,inadvertent Train a Safety Injection & Reactor Trip Occurred During Valve Reseating.Caused by Personnel Error Malfunctioning Safety Injection Handswitch. Switch Repaired
05000369/LER-1985-007-03, :on 850205,two ESF Actuations Occurred During Work on Reactor Protection & Nuclear Instrumentation Sys Channels.Caused by Procedures Allowing Simultaneous Sys Work.Procedures Revised
05000395/LER-1985-026, :on 850908,at 100% Power,Turbine Driven Emergency Feedwater Pump Indicator Read 250 Rpm.Caused by Seat Leakage Past Steam Supply Control Valve.Valve Repaired & Reset
05000482/LER-1985-042, :on 850705 & 11,ESF Actuation Occurred Resulting in Feedwater Isolation,Main Turbine Trip & Main Feedwater Pump Trips.Caused by High Water Levels in Steam Generator & Overlap Between Setpoints
05000315/LER-1985-019, :on 850420,ice Inventory within Ice Condenser Determined to Be Below Tech Spec Limits.Cause Unknown.Ice Weight of Deficient Rows Increased by Ice Replenishment Program
05000250/LER-1985-016, :on 850613,automatic Start of Emergency Diesel Generator a Occurred.Caused by Personnel Error.Generator Stopped & Returned to Normal Standby Condition,Per Operating Procedure 0-OP-023
05000339/LER-1985-007-03, :on 850701,reserve Station Svc Transformer B in Manual Operation W/Load Tap Changers Fixed at Neutral Position Due to Internal Transformer Problem,Requiring Operator Action to Maintain Bus Voltages
05000327/LER-1985-035-01, :on 850829,control Power for Diesel Generator 2B-B Lost for Several Seconds.Caused by Personnel Error Resulting in Loose Connector from Test Rig to Breaker Lugs. Suction Valves Returned to Normal
05000374/LER-1985-029-02, :on 850610,reactor Level Switches 2B21-N037AA & AB Found to Be Piped in Reverse of Sys Design.Caused by Field Change on Design Drawings Not Transferred to Contractor Installation Drawings
05000483/LER-1985-026, :on 850607,reactor Trip Occurred Due to High Negative Flux Rate.Caused by Thyristor Bank Insulator Failure.Thyristor Bank & Power Supplies Replaced
05000321/LER-1985-023-01, :on 850616,reactor Water Conductivity Monitoring Inoperable Due to Conductivity Cell.Caused by Broken Gauge Which Had Been Removed on 850614.Reactor Water Conductivity Cell Reestablished
05000370/LER-1985-016-02, :on 850528,QC Personnel Reported Discovery of Violation of Safety Train Cable Separation Criteria.Caused by Inadequate Controls by Const Dept to Ensure That Electray Reinstalled Following Removal
05000220/LER-1985-005, :on 850416,reactor Scram Occurred Due to APRM High Flux Level.Caused by Partial Closing of Turbine Control Valves Due to Disturbance in Turbine Control Sys.Work Requests Issued to Troubleshoot Sys
05000341/LER-1992-007, :on 921028,two MSIVs Exceeded Administrative Allowable Leakage Rate During Periodic Leak Rate Testing. Caused by Normal Degradation of Valve Components &/Or Contaminants.Valves Repaired/Reworked
05000389/LER-1985-006-02, :on 850516,two Control Element Assemblies in Subgroup 12 Dropped.Caused by Personnel Error in Pulling Wrong Circuit Card During Maint.Personnel Informed of Error & Greater Caution Will Be Exercised in Future
05000409/LER-1985-012, :on 850517,reactor Partial Scram Occurred Due to Low Gas or Oil Signal from CRD Mechanism.Caused by Decrease in Accumulator Pressure on CRD Mechanism 8 or 21 Until Low Pressure Setpoint Reached
05000282/LER-1992-012-01, :on 920917,DG D1 Experienced Unplanned Automatic Start During Performance of Manual Air Roll of Engine.Caused by Failure to Use Written Procedure.Operator Counseled & Instructed to Have Procedures in Hand
05000315/LER-1985-011, :on 850407,containment Purge Begun Per Approved Procedure Which Established More than on Purge Supply & Exhaust Path.Procedure Not Allowed Per Tech Spec 3.6.1.7. Procedures Changed
05000259/LER-1985-011-01, :on 850411,control Circuit Fuse Blew,Causing Partial Initiation of Primary Containment Isolation Sys. Caused by Failure of Relay 16AK72 Coil.Coil Replaced.New Fuse Installed.Recurrence Control Not Required
05000336/LER-1996-021-01, :on 960227,snubber Failure in Pressurizer Spray Line Occurred.Caused by Corrosion.Replaced Snubber Serial 12883 W/Identical Model PSA-1 Snubber
05000336/LER-1985-005, :on 850401,retest of Control Switch Caused Loss of Normal Power Signal to Be Generated to 4.16 Kv Emergency Bus 24D.Caused by Personnel Error.Personnel Instructed to Use Increased Caution in Researching Circuits
05000483/LER-1985-018, :on 850329,diesel Generator B Inadvertently Started During Surveillance Testing of Load Shedder & Emergency Load Sequencer.Caused by Technician Error. Technician Counseled & Cabinets Labeled
05000388/LER-1985-013, :on 850327,standby Liquid Control Pump a Failed 92-day Flow Verification Surveillance Test.Caused by Faulty Suction & Discharge Valves Internal to Positive Displacement Pump.Repairs Completed
05000254/LER-1985-014-03, :on 850403,fuel Pool Radiation Monitor 1A Spiked High.Caused by Electrical Noise Interference.Monitor Reset
05000395/LER-1985-005, :on 850317,reactor Trip Occurred from 100% Power Due to lo-lo Level in Steam Generator A.Caused by Burned Contact in MSIV Test Switch.Msiv Switch Replaced & All MSIVs Tested
05000395/LER-1985-004, :on 850322,noncompliance W/Reg Guide 1.108 Requirements Re Diesel Generator Testing Identified.Caused by Test Frequency Based on Per Diesel Generator Unit Basis. Procedure Revs Initiated
05000483/LER-1984-028, :on 840813,inadvertent Safety Injection Occurred.Caused by Failed Redundant Pressure Loop Going Undetected Due to Failed Lamp on Partial Trip Status Panel. Lamp Replaced
05000366/LER-1984-037, :on 841218,airlock Leaked in Excess of Tech Spec Limits.Caused by Loose Packing Follower on Inner Door Shaft Seal.Seal Repaired
05000250/LER-1984-034, :on 841213,containment Isolation Valve CV-3-204 Remained Open.Caused by Malfunction of Solenoid Valve.Air Supply to Valve Secured.Solenoid Valve Removed,Tested & Replaced
05000483/LER-1985-011, :on 850222,reactor Manually Tripped & Emergency Diesel Generator B Started & Loaded When Startup Transformer Lost.Caused by Interlock Between Transformer & Deluge Sys Due to Water Leakage & Power Loss to Rods
05000413/LER-1984-029-02, :on 841206,Westinghouse Notified Util of Insp Results Re CRD Mechanism Design.During 841215 Insp of All Unit 1 Drive rods,14 Unacceptable Drive Rods Found.Rods Replaced & Returned to Westinghouse
05000316/LER-1985-006-01, :on 850204,8-inch by 16-inch Opening Found in Wall in Quadrant 1 of Reactor Cable Tunnel,Constituting Inoperable Fire Barrier.Opening Believed to Have Existed Since Initial Plant Const.Opening Repaired
05000315/LER-1984-030-01, :on 841129,hydrogen Sampling Not Performed Per Tech Specs.Caused by Repairs Taking Place at Time Sampling Was to Be Performed.Shorter Sampling Intervals Established
05000388/LER-1985-007, :on 850129,RHR Sys Shutdown Cooling Suction Valve Closed Unexpectedly.Cause Not Stated.Pressure Switch Checked & Shutdown Cooling Established.Switch May Be Replaced Pending Evaluation
05000327/LER-1985-010, :on 850201,containment Ventilation Isolation Occurred on Train B Valves to Upper & Lower Containment Radiation Monitors RM-90-106 & 112.Caused by Failure of Power Supply.Power Supply Replaced
05000327/LER-1985-007, :on 850131,while Performing Surveillance Instruction 166.21,Train B Emergency Gas Treatment Sys Room Cooler Would Not Start.Caused by Blown Control Fuse.Fuse Replaced
05000388/LER-1985-005, :on 850119,following Reactor Scram Due to Turbine High Vibration,Suppression Chamber Vacuum Breaker Surveillance Test Completed After Tech Spec Time Limit. Caused by Cognitive Error
05000296/LER-1984-013-03, :on 841122,HPCI Inoperable When Outboard Steam Supply Isolation Valve Failed to Open.Caused by Motor Pinion Gear to Isolation Valve Being Installed Backwards. Gears Correctly Repositioned
05000389/LER-1984-009-03, :on 841104,during Scheduled Refueling Outage, Containment Isolation Signal Inadvertently Actuated
05000325/LER-1985-013, :on 850307 & 22,control Bldg HVAC Sys Manually Isolated Due to Receipt of High Chlorine Alarms at Chlorination Sys Storage Location.Cause Not Determined
05000327/LER-1984-055, :on 840817 & 20,during Work on Storage Facility for Plant Maint Insulators,Doors A028 & A029 Left Open. Caused by Personnel Failure to Realize Outer Door Part of Vital Area Boundary.Procedure Revised
05000388/LER-1985-010, :on 850223,ESF Actuation Occurred.Caused by Tripped Reactor Protection Sys Power Supply Breaker.Breaker Reset & Affected Sys Restored
05000483/LER-1985-009, :on 850215,Train a of Control Room Emergency Ventilation Sys Declared Inoperable Due to Absence of Flow Restricting Orifice.Caused by Discrepancy Between Tech Spec Flow & Design Flow
05000328/LER-1985-004-02, :on 850215 & 17,reactor Trips Occurred Due to lo-lo Steam Generator Water Level.Caused by Personnel Error & Failed Filter Cartridge Cover.New Cover Installed & Personnel Counseled
05000387/LER-1985-001-01, :on 850213,while Removing Jumpers from Refuel Floor Wall Duct Trip Units,Zone III Isolated on High Radiation Signal.Caused by Reactor Bldg Recirculation Fans Not Starting.Investigation Continuing
05000353/LER-1992-008-02, :on 920717,various Actuations of Primary Containment,Reactor Vessel Isolation Sys & Reactor Encl Secondary Containment Isolation Occurred.Caused by Blown Fuse.Fuse Sent to Mfg for Failure Analysis
05000250/LER-1985-004, :on 850129,reactor Tripped.Caused by ESF Actuation Due to Nonlicensed Operations Personnel Removing Unit 3 Motor Generator Sets a & B from Svc Rather than Unit 4 Sets.Personnel Counseled
05000250/LER-1984-023, :on 840822,while at 100% Power,Turbine Runback to 45% Power Occurred.Caused by Dropped Control Rod in Shutdown Bank a & Blown Stationary Gripper Fuse.Loose Cable Connector Replaced
05000483/LER-1984-032, :on 840820,control Room Ventilation,Containment Purge & Fuel Bldg Ventilation Isolations Actuated.Caused by Failed 15-volt Dc Power Supply in ESF Actuation Sys Cabinet. Power Supply Replaced
05000397/LER-1984-086, :on 840814,equipment Operator Failed to Complete Fire Tour Assigned Per Tech Specs.Fire Tour Reestablished & Continued Per Tech Spec 3.7.7.Operator Reprimanded
05000416/LER-1992-002-03, :on 920320,determined That Actuators for Suppression Pool Makeup Sys Dump Valves Undersized,Per Generic Ltr 89-10.Caused by Use of Min Flowrate in Actuators.Torque Switch Setting Reset
05000483/LER-1984-006, :on 840618,sample Pump for Vent Wide Range Gas Monitor Turned Off,Causing Alarm.Caused by Operator Error. Alarm Response Procedure Issued for RM-11 & RM-23 Radiation Monitor Control & Display Modules
05000327/LER-1984-054, :on 840827,reactor Trip & Turbine Trip Initiated from Steam flow-feed Feed Mismatch & Low Steam Generator Level.Caused by Loss of Power from Relay Rack 1-R-15.Relay Rack Breaker Reset
05000331/LER-1984-021, :on 840617,during Surveillance Test for Standby Diesel Generator B Operability,Diesel Tripped on High Crankcase Pressure While Loaded to Approx 2,400 Kw.Caused by Scavenging Air Blower Failure.Blower Repaired
05000499/LER-1992-002, :on 920122,over Temp Delta Temp Trip Occurred. Caused by Personnel Error.Stp Setpoint Methodology Changed to Incorporate Current Changes to Safety Analyses
05000277/LER-1995-004-02, :on 950814,TS Violation Occurred When RWCU Temp Switch Was Inoperable Due to Design Deficiency.Revised Calibr Sheet for TIS-2-12-099 to Add Note to Ensure Proper Installation of Thermistor
05000416/LER-1984-028, :on 840507,during Storm,Arcing Occurred Across Open Disconnect for 500 Kv Switchyard Breaker,Causing Loss of Power Which Resulted in Reactor Water Cleanup Reactor Isolation.Plant Shut Down
05000311/LER-1984-010-01, :on 840423,during Startup Operations,Turbine Trip & Reactor Trip Occurred.Caused by high-high Level in Steam Generator 23.Feedwater Flow Nozzle Replaced & All Sys Performed as Designed
05000373/LER-1984-035, :on 840619,cracks Found on Engine Side of Diesel Fire Pump Ob Flywheel.Cause Under Investigation by Util & Cummins Engine Co,Inc.New Flywheel Installed & Pump Tested & Returned to Svc
05000321/LER-1984-011-01, :on 840620,following Repair of Valve 1E41-F001, HPCI Turbine Isolated During Testing.Caused by Emulsification of HPCI Turbine Lubricating Oil & Broken Ball on Tappet.Hpci Repaired & Returned to Svc
05000333/LER-1984-008, :on 840313,100 F/H Heat Up Rate Exceeded Tech Spec Limits.Caused by Personnel Error.Personnel Counseled & Alarm Points Incorporated in Plant Process Computer
05000413/LER-1991-025, :on 910730,hi-hi Auxiliary Feedwater turbine- Driven Pump Sump Level Annunicator Continuously Alarmed in Control Room.Caused by Design Deficiency.Throttle Valve in Discharge Header Opened
05000281/LER-1984-009-01, :on 840415,reactor Trip Occurred as Result of Intermediate Range High Flux Trip.Caused by Spike on Range Detector NI-35.Emergency & Function Restoration Procedures Performed
05000275/LER-1984-013, :on 840407,while in Mode 3,both Subsystems to ECCS Discovered Inoperable Since 840406.Caused by Operator Failing to Identify That Limiting Condition for Operation Exceeded & Operative Procedures Revised
05000361/LER-1984-001, :on 840111,preparation of Fire Hazard Analysis & Review of Fire Protection Surveillance Results Identified Deficiencies in Fire Protection Program.Review in Progress. Complete Rept Will Be Submitted by 840228
05000373/LER-1984-019, :on 840320,while Investigating Differential Flow Indication Problem,Incorrect Calibr Data Used to Calibr Reactor Water Cleanup Sys Inlet Flow Transmitter.Caused by Conflicting Instrument Data Sheets
05000277/LER-1994-009-01, :on 940921,six Valves Associated W/Primary Containment Isolation Sys Group II Isolation Logic Closed. Caused by Lifting Common Neutral Lead on Relay 16A-K63 Part of PM Activity.Pcis Valves Replaced.W/Undated Ltr
05000341/LER-1991-009, :on 910429,loss of Power to Bus 65F Occurred Due to Mispositioned Knife Switch.Procedure 42.302.06 & Similar Electrical Surveillance Procedures Will Be Revised as Needed No Later than Sept 1991
05000277/LER-1994-008-02, :on 940909,discovered That ECCS & EDG May Have Been TS Inoperable on 940803 When ESW Outlet Valve MO-0498 Closed & Left Unattended,Causing ECT to Overflow.Valve Opened & ECT Level Restored to Normal Range.W/Undated Ltr
05000423/LER-1991-009-01, :on 910408,Train a Svc Water Portion of Svc Water Sys Declared Inoperable Due to Pipe Wall Thinning Caused by Erosion.Eroded Section of Piping Replaced W/ Erosion Resistant Piping
05000277/LER-1994-004-01, :on 940718,HPCI System Was Declared Inoperable. Caused by Problem W/Hpci Signal Isolator.Signal Isolating Device XS-2-23-144 Removed & Replaced
05000352/LER-1994-010, :on 940626,operator Pulled an Incorrect Fuse Which Caused Indicating Lights to Extinguish.Caused by Less than Adequate Attention to Detail.Both RO & Co Were Disciplined to Meet Management Expectation
05000331/LER-1983-010-03, /03L-0:on 830411,during Refueling Outage,One Snubber Found Inoperable,One Indeterminant,One Had Missing Bushing & One W/Bushing Disengaged.Caused by Procedure Error During Previous Maint
05000458/LER-1991-006, :on 910401,operations Cooperative Student Failed to Replace High Radiation Area Barrier Rope Barricade.New Procedural Requirments to Replace High Radiation Entrance Barriers Initiated
05000263/LER-1993-009-01, :on 930826,draftsman Discovered Unmarked Computer Diskette Containing Safeguards Info Drawings on Desk.Caused by Inadequate Safeguard Controls Procedures. Heightened Security Measures Implemented
05000352/LER-1994-007, :on 940427,refuel Floor Secondary Containment Isolated & SGTS Initiated Due to Low Negative Differential Pressure Signal.Caused by Severe Storm.Normal Ventilation to Refuel Floor Restored After Storm Passed
05000277/LER-1994-002-03, :on 940426,confirmed That Circulating Water Intake Composite Sampler Sys Not Properly Functioning.Caused by Small Valve on Sys That Became Plugged.Composite Sample Valve & Line Flushed
05000277/LER-1990-034, :on 901112,discovered That Emergency Diesel Generator Droop Selector Switches in Parallel Position. Caused by Personnel Error.Personnel Involved Counseled on Importance of Attention to Detail
05000445/LER-1990-044, :on 901130,reactor Operator Performed Test on Wrong Train of Charging Sys Due to Procedural Inadequacy. Results for Previously Performed Tests & Enhancements of Test Info on Work Orders Reviewed
05000336/LER-1990-010-01, :on 900621,door Identified as Being in Configuration Not Consistent W/Bechtel Design Drawings Due to Lack of Knowledge of HELB Requirements for Area
05000336/LER-1990-009-01, :on 900617,facility Experienced Inadvertent Partial Actuation of Train B of Auxiliary Exhaust Actuation Sys.Cause Undetermined.Two Addl Actuations Occurred on 900711
05000277/LER-1994-001-01, :on 940119,TS Violation Occurred Due to Fire Detection Sys Breaker Open W/No Hourly Firewatch in DG Cardox Room.Closed Breaker & Restored Fire Detection Instrumentation
05000277/LER-1993-015-01, :on 931201,TS Violation Occurred Due to Improperly Secured Main Stack Particulate Filter.Filters Changed & Gas Marnelli Samples Obtained to Identify & Quantify Nuclides in Main Stack Effluent
05000334/LER-1990-011, :on 900719,ESF Actuation - Inadvertent Trip of Reactor Coolant Pump a Occurred During Maint Surveillance Procedure.Caused by Personnel Error.Procedures Revised
05000333/LER-1990-023, :on 901019,manual Reactor Scram Due to Blocked Circulating Water Intake Screens
05000369/LER-1990-032, :on 901117,unit Experienced Turbine Trip, Followed by Reactor Trip.Cause Unknown.Control Room Personnel Initiated Turbine Exhaust Hood Spray
05000440/LER-1990-031, :on 901022,control Rod Withdrawn W/O First Demonstrating by Channel Check That Scram Discharge Vol Level Instrumentation Operable
05000352/LER-1993-010-04, :on 930820,actuation of PCRVICS & ESF Occurred After Reactor Enclosure Exhaust Plenum Radiation Monitor Spuriously Tripped.Cause Not Determined.Sensor Converter for Radiation Monitor Replaced During Testing
05000266/LER-1990-007, :on 900712,error Indicating Potential for Failure to Comply W/Peak Cladding Temp Acceptance Limit Noted.Caused by Human Error.Util Committed to Reduced Height Dependent Heat Flux Hot Channel Factor Limit
05000339/LER-1990-009-02, :on 901028,2J 416-volt Emergency Bus Deenergized Due to Design Deficiency
05000155/LER-1993-005, :on 930714,discovered That Primary Containment Spray Motor Operator Capability May Have Been Insufficient to Open MOV-7064 Under Degraded Conditions.Torque Switch Will Be Reset & Votes Testing Performed
05000304/LER-1988-001, :on 880108,nuclear Station Operator Failed to Log Delta I W/Nuclear Instrumentation Channel in Test.Caused by Failure to Respond to Control Room Indication.Operator Training Conducted
PY-CEI-NRR-0015, Forwards Public Version of Rev 1 to Emergency Plan OM-15A, Incorporating Encl Responses to Questions in NRC 811221 & s & Addressing SER Outstanding Issue 19
05000353/LER-1993-007-02, :on 930617,alarm Indicated TIP Sys Shear Valve Was Inoperable.Cause Interminate.Isolated Occurrence
05000213/LER-1993-006, :on 930523,EDG Failure Occurred Due to Diode Assembly Short.C/As:Installed New Diode Assemblies & Ventilation Fan Motors for Both Generators
05000409/LER-1990-003, :on 900608,five Required Fire Protection QA Audits Missed.Caused by Scheduling Error Since 890101.Util Reverted to Original QA Audit Schedule
05000245/LER-1990-009-01, :on 900511,determined That House Heating Steam Sys Could Potentially Degrade Environ Classified, Eeq Mild Environs. Caused by Incorrect Conclusion Drawn from 1973 Study.Plant Mods Implemented
05000277/LER-1990-011-01, :on 900503,discovered That Tech Spec 3.4.1 Not Performed on 6-wk Frequency as Required.Caused by Personnel Error.Tracking of Surveillance Activities Scheduled to Be Transferred to Improved Software Package
05000483/LER-1990-005, :on 900501,reactor Trip,Auxiliary Feedwater Actuation & Feedwater Isolation Occurred Due to Turbine Trip on Loss of Main Generator Stator Cooling Water.Caused by Blown Fuse.Fuse Replaced & Logic Changed
05000382/LER-1990-005, :on 900420,condenser Vacuum Pump Discharge Wide Range Gas Monitor Setpoint Discovered to Be Incorrect.Caused by Inadequate Change Procedure for Data Base Manual. Administrative Procedures Revised
05000328/LER-1990-010, :on 900416,containment Ventilation Isolation Occurred.Caused by Allowing Gaseous Radiation Level to Increase Too Close to Alarm Setpoint.Recovery from Isolation Initiated
05000285/LER-1990-011, :on 900402,inadvertent Actuation of Pressurizer Pressure Low Signal Occurred While Performing Calibr Procedure.Caused by Inappropriate Action by Technician Involved.Validation of Procedures Reviewed
05000412/LER-1993-003, :on 930205,steam Generator Blowdown Sys Isolated Due to High Level in Steam Generator Blowdown Tank. Caused by Discrepancies Between Actual & Indicated Tank Level.Temporary Operating Procedure Written
05000413/LER-1990-023, :on 900330,ESF Actuation Occurred.Caused by Defective Procedure for Erroneous Info.Procedure Will Be Revised & Incident Will Be Reviewed by Exempt Performance Personnel
05000324/LER-1989-013, :on 890909,HPCI Auxiliary Oil Pump Developed Shaft Seal Leak.Caused by Failure of Shaft Seal Due to Degradation of Adhesive That Bonds Seal Elastomer to Metal Retaining Ring
05000293/LER-1991-001, :on 910125,automatic Primary Containment Isolation Control Sys Group 5 Actuation Occurred,Resulting in Closing of RCIC Turbine Steam Supply Isolation Valves. Caused by High Flow Conditions
05000322/LER-1990-007, :on 900907,unplanned Actuation of ESF Sys Occurred During I&C Surveillance Test.Caused by Inadequate procedure.SP44.650.16 Revised to Require That Leads Lifted & Individually Separated
05000352/LER-1990-005, :on 900211,no Fire Watch Insps for Rooms 103, 114 & 117 on Elevation 177 Ft in Reactor Encl Performed by Personnel.Caused by Personnel Error.Person Involved Disciplined.Training Program Improved
05000499/LER-1990-003, :on 900214,discovered That Train B Fuel Handling Bldg Exhaust Air Filter Outlet Damper Would Not Open.Caused by Wiring Error Due to Failure of Technicians to Follow Work Instructions.Technicians Counseled
05000413/LER-1990-011, :on 900215,discovered That Control Room Doors Were More Difficult to Open than Normal.Ventilation Sys Found to Be Incapable of Maintaining Positive Pressure. Caused by Design Deficiency.Walls Sealed
05000318/LER-1989-012-01, :on 891227,core Alterations Performed W/Only One of Two Containment Vent Valves Closed.Caused by Procedural Deficiency.Procedures Revised to Include Valve & Surveillance Test Program Instruction Revised
05000327/LER-1990-002-02, :on 900127,control Room Isolation Occurred When Circuit Breaker Opened Supplying Power to Radiation Monitor. Caused by Failure by Personnel to Exercise Sufficient Caution.Responsible Engineers Reinstructed
05000334/LER-1990-004, :on 900124:discovered That Control Rod Positions Not Recorded on Operator Logs on 890425 When Control Rod Insertion Limit Monitor & Deviation Alarm Out of Svc.Cause Not Stated.Personnel Counseled
05000482/LER-1989-020, :on 891117,determined That as-built Configuration of Housing for Both Trains of Containment Cooling Fan HXs Not Seismically Qualified to Withstand Sse. Addl Seismic Restraints Installed
05000414/LER-1989-020-01, :on 891111,low Filtered Exhaust Flow Discovered by Control Room Operators During Observation of Indications. Caused by Design Oversight Re Interaction of Sys/Components. Clothes Dryer Filters to Be Modified
ST-HL-AE-4779, 1993 Annual Environ & Annual Radiological Environ Operating Repts South Tx Project Electric Generating Station. W/
05000423/LER-1990-002, :on 900109,partial Train a Containment Depressurization Actuation Signal Generated.Caused by Personnel Error.Warnings Added to Production Maint Mgt Sys for Recirculation Spray Sys Pump Breakers
05000334/LER-1989-019-01, :on 891227,discovered That Manual Reactor Trip Operating Surveillance Test Not Performed within Required Frequency Prior to Previous Reactor start-up on 891224. Caused by Inadequate start-up Procedures
05000277/LER-1989-016, :on 890720 & 22,LPRM Detector 4B-40-33 Spiked High,Resulting in Full Reactor Scram Signal While in Cold Shutdown.Caused by Design/Mfg Defect in GE Detector. Detector Placed in Bypass Position
05000327/LER-1989-030, :on 891204,fire Suppression Sys Deluge Valve Isolated More than 1 H W/O Required Continuous Fire Watch Establishment.Caused by Personal Communication Breakdown. Valve Opened & Foreman in Charge Counseled
05000413/LER-1989-029-01, :on 891213,determined That Max Actuator Torque Switch Setting Insufficient to Overcome Friction Force Due to Age Hardening of Elastomeric Seat Matl on Bif/General Signal Corp Valve.Also Reported Per Part 21
05000293/LER-1989-031, :on 891024,closing Times for Two in-series Primary Containment Isolation Valves Exceeded Acceptance Criteria During Shutdown Testing.Cause Undetermined.Closing Time Retested W/Satisfactory Results
W3F1-2016-0037, Annual Radiological Environmental Operating Report - 2015
RC-14-0129, Response to Request for Additional Information on License Amendment Request LAR-06-00055 and to Adopt NFPA 805
DCL-2003-510, Annual Report for 2002 on Discharge Monitoring, in Accordance with Order 90-09, NPDES No CA0003751
AEP-NRC-2024-86, Unit 2 - Decommissioning Funding Plan for Independent Spent Fuel Storage Installation
05000318/LER-1989-003, :on 890307,plant Shutdown Due to Air Leak on Feedwater Regulating Valve (Frv).Caused by Failure to Identify Need to Perform Adequate Preventive Maint on Positioner.Frv Controller Placed in Manual
05000369/LER-1987-012-02, :on 870709,diesel Generator Load Sequencer 1A Actuated in LOCA Mode During Routine Periodic Test of Slave Relays in Solid State Protection Sys.Caused by Defective Procedures.Slave Relay Test Procedures Revised
05000327/LER-1987-025, :on 870506,determined That Tech Spec Surveillance Requirement 4.6.4.3.a Acceptance Criteria Not Being Fully Implemented.Caused by Inadequate Procedure. Surveillance Instructions to Be Revised
05000213/LER-1986-041, :on 860830,feedwater Regulating Valve FW-FCV-1301-1 to Steam Generator 1 Became Stuck Open,Causing Manual Reactor Trip.Caused by Failure of Weld Between Stem & Plug.Failed Part of Weld Sent to Mfg
05000483/LER-1987-008, :on 870504,util Maint Electricians Blocked Open Fire Door W/O Establishing Continuous Fire Watch.Caused by Lack of Understanding of Tech Spec Requirements.Util Maint Personnel Counseled
05000259/LER-1986-028-01, :on 860828,personnel Access Doors from Turbine Bldg Into Reactor Bldg Opened at Same Time Resulting in Momentary Loss of Secondary Containment.Caused by Rectifier Solenoid Failure.Rectifier Replaced
05000369/LER-1986-007-01, :on 860325,reactor Tripped on Steam Generator Lb lo-lo Level Signal.Caused by Failure of Bussman Fuses. Indicating Fuses Will Be Replaced W/Nonindicating Fuses
05000289/LER-1988-005-02, :on 880925,RCS Heatup Rate Increased to 60 F Per Hour When Third Reactor Coolant Pump Started.Caused by Procedural Error.Operators Trained & Procedures Revised Re Primary Monitoring Method Used
05000348/LER-1986-009, :on 860714,ESF Actuated When Penetration Room Filtration Sys Started Automatically.Caused by Personnel Error During Removal of Radiation Monitor R-25A from Svc for Maint.Technician Counseled
05000305/LER-1986-003, :on 860326,potential Problem Found w/long-term Reliability of Both Backup Emergency Ac Diesel Generators. Caused by Numerous Fast Starts of Diesel Generator W/O Full Main Lube Oil Pressure
05000315/LER-1986-006-01, :on 860326,discrepancy Noted Between Reactor Protection & Engineered Safeguards Sys Time Response Test Procedure & Tech Spec Requirements.Reactor Coolant Pump Undervoltage Relay Response Time Omitted.Procedure Revised
05000374/LER-1984-054, :on 840818,isolations of Reactor Water Cleanup Occurred.Under Same Conditions,Two Other Reactor Water Cleanup Isolations Occurred.Caused by High Differential Flow.Corrective Actions Under Review
05000315/LER-1984-018-01, :on 840814,CRID IV Inverter Abnormal Alarm Activated Due to Crid Failure,Resulting in Reactor Trip & Safety Injection.Caused by Leaking Water from Emergency Shower & Eyewash Station.Design Change Planned
05000499/LER-1995-004, :on 950404,TS 3.0.3 Entered Due to Inoperability of Digital Rod Position Indication Sys.Caused by Loose Connection of Control Wire Internal to Automatic Transfer Switch.Wire Reterminated
05000250/LER-1984-022, :on 840721 & 22,daily Calibr of Nuclear Power Range (Thermal Power Calculation) Not Performed Per Tech Specs.Caused by Personnel Oversight.Checks for Calculations Made & Supervisory Discussions Held
05000285/LER-1984-012, :on 840717,boron Concentration in Safety Injection & Refueling Water Tank Below Tech Spec Limits. Caused by Analytical Error.Boron Concentration Maintained at Higher Level
05000397/LER-1984-036, :on 840423,during Initial Power,Test Equipment Installed to Facilitate Troubleshooting Feedwater Control Sys Injected Test Signal Into Feedwater Control Circuit. Caused by Improperly Positioned Bypass Switch
05000370/LER-1990-008-04, :on 901227,during Rod Movement Testing Shutdown Bank E Fell Into Core.Manual Reactor Trip Initiated.Caused by Possible Equipment Failure.Technical Review Performed. Reactor Restarted
05000352/LER-1987-035, :on 870715,unexpected Actuation of Nssss Occurred.Caused by Personnel Error Since Scope of Work Performed & Procedures Followed Not Specific.Preventive Maint Program Revised