L-17-233, High Frequency Supplement to Seismic Hazard Screening Report, Response to NRC Request for Information, Per 10CFR50.54(f) Regarding Recommendation 2.1 of the Near-Term Task Force (NTTF) Review of Insights from the Fukishima Dai-ichi Accident
RS-14-029, Status of Fish Communities and Sport Fishery in the Kankakee River and Tributary Streams: 2005 Basin Survey
NRC 2006-0090, License Amendment Request 251; Technical Specification 5.6.5, Reactor Coolant System Pressure and Temperature Limits Report
05000348/LER-1981-001-03, /03L-0:on 810116,RHR Flow Lost.Caused by Loss of Power to 1A RHR Pump as Result of Feeder Breaker to Start Up Transformer 1A Opening.Diesel Generator 1-2A Energized Bus 1F & RHR Pump Restarted.Transformer 1A re-energized
05000219/LER-1980-033-03, /03L-0:on 800806,24-h After Reactor Mode Switch Was Placed in Run,Torus Oxygen Concentration Found in Excess of 5%.Caused by Torus Oxygen Analyzer Out of Calibr & Reduced Flow Capability of Nitrogen Purge Sys
05000271/LER-1979-031-03, /03L-0:on 791110,during Refueling/Maint Outage, Hangers RCIC-H-82 & HPCI-HD-67B Removed from Svc.Removal Unnoticed During Review.Caused by Personnel Error.Hangers Returned to Svc
05000317/LER-1979-070-03, /03L-0:on 791122,during Log Readings,Discovered That Reactor Protection Sys Channel C Containment Pressure Signal Had Deviated by Greater That 0.1 Volts from Other Channels.Caused by Faulty Isolator 1-E/E-5313C
05000259/LER-1979-029-03, /03L-0:on 791016,design Flow Rate Testing Not Performed on Primary Containment Purge Sys.Caused by Misinterpretation of Tech Specs.Design Flow Completed & Tech Specs Reviewed
05000325/LER-1979-077-03, /03L-0:on 791004,while Performing Cycling Test, Valve X6OD Lost Indication,Valve X82A Switch Would Not Operate & Valves X243 F & X244 E Had Dual Indication.Caused by Defective Switches & Air Tubing Leaks
05000267/LER-1979-059-03, /03L-0:on 791109,during Reactor Shutdown for Maint,Boiler Feeder Snubber BFS-412 Observed Inoperable. Caused by Empty Hydraulic Oil Reservoir.Reservoir Refilled
05000348/LER-1978-024-03, /03L-1 on 780408:while Changing Turbine Governor Valve Control,Load Rejection of Approx 170 MW Resulted in Momentary Temp Average Increase.Control Rods Automatically Initiated & Average Reduced
05000334/LER-1978-062-03, /03L-0 on 780313:constant for Control Rod Changed from 12 to 20 Steps Because Nuisance Alarms Caused Rod Position Deviation Monitor to Be Inoperable.Caused by Failure to Check Negative Effects Before Changing Constant
05000336/LER-1979-039-03, /03L-0:on 791128,while Shut Down for Repair of Feedwater Sys Nozzles,Maint Was Performed W/O Local Leak Rate Test,Therefore Leakage Rate Not Confirmed.Cause Not Stated.Administrative Procedures Mod
05000325/LER-1980-053-03, /03L-0:on 800607,during Normal Reactor Bldg Tour During Refueling,Inner & Outer Doors of 50-ft Air Lock Found Open.Caused by Burned Coil in Inner Door Interlock Solenoid. Coil Replaced & Air Lock Access Restored
05000293/LER-1980-078-01, /01T-0:on 801030,review of Results of Salt Svc Water Sys Per IE Bulletin 79-14,indicated Design Deficiency. Caused by Installation of Salt Svc Water Anchor Point Outside Area Tornado Missile Barrier Protection
05000316/LER-1982-031-03, /03L-0:on 820330,during Preventive Maint Insp,Roll Up Fire Door 314 Would Not Close Upon Automatic Closure Activation.Caused by Adjusting Wheel Rivets Missing from Automatic Closure Mechanism.Discharge Spring Adjusted
05000315/LER-1982-045-03, /03L-0:on 820528,security Officer Discovered Low Pressure Carbon Dioxide Sys for Auxiliary Cable Vault Isolated W/O Personnel on Duty.Caused by Personnel Error. Need for Full Compliance W/Fire Protection Emphasized
05000265/LER-1983-020, Revised LER 83-020/01T-1:on 831028,weld 02B-S9,22-inch Pipe to Cap,Weld 02BS-S12,28-inch Elbow to Pipe & Weld 02BS-F14, 28-inch Pipe to Elbow Weld Had Circumferential Linear Indications
05000366/LER-1983-099, Updated LER 83-099/03X-1:on 830925 & 1005,hydrogen Dioxide Analyzer a Declared Inoperable During Procedure HNP-2-3882 & Out of Calibr,Respectively.Caused by Worn Diaphragms in Sample Pump a & Instrument Drift
B12246, Forwards Reviews of Isap 1.14.2, Install New 480-Volt Load Ctr & Rearrange Equipment in Fire Area S-8, 1.14.4, Install Remote Shutdown Instrumentation Panel & 1.61, Pressurized Thermal Shock, Per 850517 Commitment
L-86-380, Forwards Application to Renew NPDES Permit FL0002208, Per Environ Protection Plans,Section 3.2.4
05000482/LER-1987-052, :on 871118,installed Instrument Termination Splices Failed to Meet Environ Qualification Requirements. Caused by Undetailed Work Instructions,Inadequate Training & Lack of Mfg Instructions.Splices Reworked
05000341/LER-1987-051, :on 870929,differential Pressure Actuation of Emergency Equipment Cooling Water Occurred.Caused by Design Deficiency in Reactor Bldg Closed Cooling Water Sys.Time Delay on Pressure Switches Lengthened
0CAN039808, Submits Response to GL 97-06, Degradation of SG Internals. Util Has Participated in Development of Generic Guidance Documents to Address Degradation of SG Internals W/Listed Industry Groups
05000346/LER-1983-038-03, /03L-1:on 830725,half Trip of Steam & Feedwater Line Rupture Control Sys Actuation Channel 1 & Spurious Trip of Logic Channel 1 Occurred.Caused by Failed Power Supply & Relay Driver Board,Respectively.Parts Replaced
05000344/LER-1988-022, :on 880704,Train a Safety Injection Initiated During Plant Heatup.Caused by Spurious Electronic Spike on One Pressurizer Pressure Channel Generated When Test Switch Placed in Test.Troubleshooting Conducted
05000341/LER-1988-011, :on 880313,failure to Perform Shiftly Surveillance within Required Time Occurred.Caused by Failure to Designate Person to Perform Surveillance When Personnel Reassigned.Requirement Added
05000498/LER-1987-022, :on 871206,control Room Toxic Gas Monitors Inoperable.Caused by Inadequate Training Program for Toxic Gas Monitoring Sys Operation & Channel Checks.Monitor Operation Training & Logging Procedure Planned
05000382/LER-1985-051, :on 851206,reactor Trip Occurred on Low Dnbr. Caused by Operator Error.Plant Conditions Stabilized in Mode 3.Operators Given Guidance Reemphasizing Importance of Adherence to Procedures
05000324/LER-1982-071-03, /03L-1:on 820701,primary Containment Penetrations & Isolation Valves Found to Have Leak Rate Greater than 0.60 L.Valves & Penetrations Repaired & Returned to Svc.No Further Action Planned
05000249/LER-1983-035-03, /03X-1:on 831004,during Drywell Insp,Water Observed Leaking from Recirculation Pump Bowl Drain A. Probably Caused by Socket Weld Joint Bottoming Out.Affected Piping Replaced During Outage
05000249/LER-1983-029-03, /03X-1:on 830726,Reactor Water Level Surveillance Dis 1500-3 & Reactor Water Level Sensor Lits 3-263-73 a Required Initial Dp Loading of 260 Inches of Water to Move Indicator.Caused by Worn Diaphragm Switch
05000334/LER-1983-043-03, /03L-0:on 831229,main Steam Safety Valve Effluent Monitor Declared Inoperable.Cause Unknown.Monitor Left Energized to Ensure Proper Operation & Returned to Svc
05000334/LER-1983-028-03, /03L-0:on 830926,charging Isolation Valve MOV-CH-310 Would Not Reopen After Being Stroked Shut. Caused by Dislodged Contactor Drive Pin Resulting in Misalignment.Pin Realigned
05000334/LER-1983-027-03, /03L-0:on 830925,operator Attempting to Raise Voltage on Sys Station Svc Transformer 1A W/Installed Tap Charger Used Incorrect Voltmeter,Causing Overexcitation of Transformer.Caused by Operator Error
05000334/LER-1983-013-03, /03L-0:on 830505,during Normal Operation,Chlorine Detector B Wick Observed Dry While Electrolyte Reservoir Indicated Full.Caused by Binding Level Indicator. Indicator Freed
05000318/LER-1983-009-03, /03L-0:on 830116,pressurizer Level Deviated from Program Band by More than +/-5% Several Times & Pressurizer Pressure Decreased Below 2,225 Psia.Caused by Temp Swings Due to Startup Testing.Tech Spec Change Requested
05000324/LER-1982-141-03, /03L-0:on 821218,primary Containment Atmosphere Oxygen Analyzer 1-CAC-AT-1263-2 Showed Upscale Indication of Drywell Oxygen Concentration.Caused by 1263-2 Analyzer Zero Shift.Analyzer Calibr & Returned to Svc
05000254/LER-1982-039-03, /03L-0:on 821224,diesel Generator 1/2 Failed to Start Following Preventive Maint.Caused by Crack in 1/4-inch Copper Air Line.Crack Due to Crimp in Right Angle Bend in Line & Fatigue Failure at Stress Point.New Line Rebuilt
05000325/LER-1978-085-03, /03L-0 on 781227:failed to Perform Quarterly Transmitter & Recorder Calibr for Drywell Oxygen Monitor CAC-AT-1259-2 in Mar & Sept 1978 Due to Misunderstanding of Tech Specs.Periodic Test Schedule Will Be Written
05000333/LER-1978-112-03, /03L-0 on 781226:discovered That Surveillance Requirements Not Performed on Air Operated Isolation Valves. Procedures Revised & Testing Completed W/Satisfactory Results
05000265/LER-1983-023-03, /03L-0:on 831128,during Main Steam Line High Flow Calibr Qis 21-1,pressure Switch DPIS 2-261-2K Found to Trip at 148.5 Psid.Caused by Instrument Setpoint Drift.Instrument Recalibr
05000346/LER-1983-040-03, Auxiliary Feed Pump 1-1 Failed to Respond to Speed Change Signals from Automatic & Manual Control.Caused by Design Deficiency in Clutch Mechanism.New Design Slip Clutch Installed
05000265/LER-1983-021-01, /01T-4:on 831027,while Reviewing Ultrasonic Test Data,Three Linear Indications Identified in Reactor Recirculation Sys Piping.Caused by Intergranular Stress Corrosion Cracking
05000237/LER-1983-076-03, Unidentified Drywell Leakage Calculated to Be 3.08 Gpm.Caused by Cut in Seal Ring Seating on Feedwater Check Valve Body.Cut silver-soldered & New Seal Ring Installed
05000267/LER-1983-051-03, /03L-0:on 831119,alternate Cooling Method Diesel Generator Taken Out of Svc When Air Intake Filter Section & Generator Mounting Assembly Found Damaged.Possibly Caused by Mounting Bolt Washout & Concurrent Vibration
05000321/LER-1983-116-03, /03L-0:on 831202,links K96A & N Determined Open at Steam Condensing Mode Flow Control Valve IE11-F053A.Cause Unknown.Links Closed.Operation Verified
05000325/LER-1983-052-03, /03L-0:on 831122,while Performing Operability Test,Control Room Indicators CAC-LI-2601-1 & LI-4177 & Remote Shutdown Panel CAC-LI-3342 Showed Level Indication - 26 Inches.Caused by Cracked Open Drain Valve
05000321/LER-1983-104-03, /03L-0:on 831118,while Performing Hydraulic Shock & Sway Arrestor Insp & Functional Test,Snubber 1B31-SS-A7 Discovered W/Low Reservoir Fluid Level.Caused by Inadequate Fluid Reserve Due to Leakage.Snubber Rebuilt
05000334/LER-1983-039-03, /03L-0:on 831126,level Channel L-RC460 Failed Channel Check (4% Deviation Between Level Channels).Caused by Packing Leak on Instrument Valve.Internals of Instrument Valves Replaced & Ref Leg Refilled
05000324/LER-1983-094-03, /03L-0:on 831102,control Rod 38-23 Did Not Have RTGB Position Indication at 12 & Control Rod 30-39 Did Not Have RTGB Position Indication at 04.Caused by Problems on Indication Reed Switch of Each Rod
05000346/LER-1983-061-03, /03L-0:on 831109,120-volt Ac Essential Instrumentation Panel Y2 Deenergized,Placing Unit in Action Statement of Tech Spec 3.8.2.1.Caused by Blown Main Fuse in Normal Power Supply Inverter YV2
05000237/LER-1983-079-03, /03L-0:on 831018,while Testing MSIVs 1B & 2B,half Scram Received.Relay 590-102H Found Dropped Out.Caused by Misalignment of Plate Operating Actuating Arm for Limit Switch 1B.Actuating Plate Readjusted
05000324/LER-1983-091-03, /03L-0:on 831026,isolation Valve E51-F043C Would Not Reopen.Caused by Broken Bakelite Nipple in Valve Control Switch,Model EF4.Switch Module B47173 Replaced & Valve F043C Cycled & Returned to Svc
05000346/LER-1983-068-03, /03L-0:on 831129,rod 7-12 Dropped to 0% Withdrawn. Asymmetrical Condition Caused Integrated Control Sys to Run Back to 60%.Caused by Opening Motor Programmer Phase Fuse Cc.Fuse Replaced
05000247/LER-1983-038-03, /03L-0:on 831011,during Refueling Water Storage Tank Level Surveillance Test,One of Two Level Alarm Set Points Found Above Max Level.Cause by Drift of Foxboro Model 635-BROCHA Level Alarm Bistable.Bistable Reset
05000271/LER-1983-028-03, /03L-0:on 831014,during Normal Operation,Smoke Coming from RHR Pump 1D Motor Caused Operator to Immediately Remove All Fuses from Pump Motor Breaker,Making LPCI Inoperable.Smoke Caused by Dirt & Oil Film
05000267/LER-1983-044-03, /03L-0:on 831011,bearing Water Makeup Pump P-2105 Removed from Svc W/Reactor Operating at 65% Power.Caused by Two Leaking Valves & Two Leaking Filters in Need of Repair. Pump Returned to Svc within 24 H
05000336/LER-1983-027-03, /03L-0:on 830926,during Refueling as Received Steam Set Pressure Test 2-RC-201 Performed.Valve Failed Test Exceeding Set Pressure by Greater than 1%.Cause Unknown.Valve Rebuilt
05000247/LER-1983-039-99, /99X-0:on 831017,while in Cold Shutdown,Pin Hole Leak Identified in Supply Line to Water Box 21-2.Caused by Internal Corrosion.Pipe Weld Repaired & Fan Cooler Satisfactorily Retested
05000321/LER-1983-048-03, /03L-0:on 831004,plant Svc Water Pump 1C Overload or Lockout Relay Tripped & Alarm Received in Control Room. Caused by Electrical Insulation Breakdown in Motor Winding on Pump 1P41-C001C.Pump Motor Rewound
05000321/LER-1981-112-03, Torus to Rx Bldg Differential Pressure Switches 1T48-N210,N211,2T48-N210 & N211 Proof Press Not within Tech Spec Limit.Caused by Switch Misapplication.Also Reported Per Part 21
05000247/LER-1983-034-03, /03L-0:on 830916,containment Gas & Particulate Monitors R-11 & R-12 Declared Inoperable When Monitors Read Downscale.Cause Not Stated.Connector Repaired & Minor Adjustments Made
05000249/LER-1983-032-03, /03L-0:on 830921,valve LPCI 1501-11B Closed During Installation of Terminal Jumper.Caused by Technician Inadvertently Placing Terminal Jumper on 903-3 Panel Instead of 903-10 Panel
05000265/LER-1983-017-03, /03L-0:on 830924,during RCIC Turbine Area High Temp Switch Calibr QIS-28,temp Switches TS 2-1360-15B,16B & 14D Tripped Above Tech Spec Limit.Caused by Setpoint Drift. Switches Replaced
05000282/LER-1983-021-03, /03L-0:on 830830,during Surveillance Test MV-32035,cooling Water Header Isolation Valve B Failed to Close.Caused by Failure of GE Auxiliary Switch,Part CR105X100P.Switch Replaced
05000324/LER-1983-080-03, /03L-0:on 830831,following Scram,While Utilizing HPCI Sys as Heat Sink for Reactor,Suppression Pool Water Level Exceeded Tech Specs.Caused by HPCI Pump Min Flow Valve Failing in Open Position.Valve Closed
05000366/LER-1983-105-03, /03L-0:on 830930,drywell Floor Drain Leakage Increased in Quantity Greater than 2 Gpm.Caused by Increased Reactor Pressure During Scram Recovery.Leakage Decreased to 2 Gpm After Period of 20 H
05000324/LER-1983-082-03, /03L-0:on 830902,suppression Pool Level Exceeded Specs W/Value of -26.25 Inches.Caused by Failure of Operator to Adequately Monitor Level While Instrumentation Out of Svc Due to Plant Mod.Level Returned to Specs
05000366/LER-1983-092-03, /03L-0:on 830831,RHR Svc Water Pump 2A Declared Inoperable After Motor Bearing Began to Overheat While Trying to Make Up Water to Circulating Water Flume.Caused by Partially Blocked Cooling Water Line
05000324/LER-1983-059-03, /03L-0:on 830822,discovered Automatic Depressurization Sys Initiation Logic a Switch 2E11-PS-N016A Would Not Respond to Applied Test Signal.Caused by Corrosion of Switch Internals & Setpoint Drift
05000366/LER-1983-110-03, /03L-0:on 831025,split Ring Component of Plant Svc Water Pump (2P41-C001C) Seismic Restraint Not in Position.Caused by Vibrations Loosening Nuts & Bolts.Ring Repositioned & Secured in Proper Position
05000366/LER-1983-093-03, /03L-0:on 830901,remote Reactor Pressure Indicator 2C82-R006 Failed to Indicate within 40 Psig of Control Reactor Pressure Indicator 2B21-R004A & Declared Inoperable. Caused by Setpoint Drift.Indicator Calibr
05000324/LER-1983-073-03, /03L-0:on 830824,during Surveillance,Instrument Indication of Reactor Water Cleanup Sys Differential Flow Indicator 2-G31-R615,GE Model 180,indicated High.Caused by Entrapped Air in Transmitter Sensing Lines
05000373/LER-1982-175-03, /03L-0:on 821224,div 2 Position Indicator of Containment Vacuum Breaker 1PCOO1B Would Not Indicate Closed.Cause Undetermined.Work Request Written,Insp Performed & Vacuum Breaker Repeatedly Cycled
05000321/LER-1983-077-03, /03L-0:on 830815,P-1 Computer Programs Calculated Core Max Fraction of Limiting Power Density to Be 1.014 & Cmapr to Be 1.000 Contrary to Tech Spec Requirements.Caused by Inaccurate P-1 Base Distribution Program
05000321/LER-1983-075-03, /03L-0:on 830816,reactor Water Cleanup Sys Differential Flow Transmitter 1G31-NO36 Discovered Out of Calibr.Caused by Setpoint Drift.Transmitter Calibr
05000271/LER-1983-018-03, /03L-0:on 830809,HPCI Sys Declared Inoperable After Tripping & Resetting Occurred During Vibration Test. Caused by Normal Vibration Loosening Set Screw Holding Piston in Position on Ball & Tappet Holder
05000249/LER-1983-028-03, /03L-0:on 830723,differential Pressure Switch Ps 1349A Actuated Above Tech Spec Limit of 32.0 Inches of Water.Caused by Inadvertent Adjustment of High Differential Pressure Isolation Potentiometer
05000321/LER-1983-091-01, /01T-0:on 830827,during Maint Activities in Drywell,Safety Relief Valve Discharge Line Vacuum Breaker (1B21-F037D) Discovered Stuck Partially Open.Nine Other Vacuum Breakers Failed to Seat Properly
05000237/LER-1983-056-03, /03L-0:on 830716,investigation of torus-to-drywell Vacuum Breaker Alarm Revealed Closed Vacuum Breaker But Limit Switch Not Made Up.Caused by Loose Switch Bracket. Switch Repositioned
05000267/LER-1983-026-03, /03L-0:on 830722 & 23,reactor Bldg Sump Pump Proportional Sampler Discovered Inoperable.Caused by Personnel Error.New Sampler Not Functionally Tested Prior to Returning Sys to Svc.Procedures Will Be Revised
05000254/LER-1983-029-03, /03L-0:on 830711,while Repacking 1-1001-65B RHR Svc Water Pump,Pump Inboard Bearing Surfaces Found Pitted & Imbedded W/Dirt.Pump Packing Sleeve Slightly Worn.Caused by Leakage Through Worn Packing & Packing Sleeve
05000321/LER-1983-059-03, /03L-0:on 830610,personnel Received Fission Product Monitor High/Low Flow Alarm & Found Monitor W/No Drywell Sample Flow.Caused by Personnel Lifting Wire from Coil of K5 Relay.Wire Replaced
05000334/LER-1983-016-03, /03L-0:on 830528,supply Breakers to 4,160-volt Buses 1A & 1B Opened Due to Inadvertent Operation of Pilot Wire Protection Relay,Causing Loss of Offsite Ac Source & Reactor Trip.Caused by Ground Fault on Panel
05000244/LER-1983-014-03, /03L-0:on 830329,during Refueling Calibr,Certain Steam Generator Level Transmitter Outputs Shifted Low by 2 to 2.5% of Span.Caused by Instrument Drift.Transmitters Recalibr
05000366/LER-1983-140-03, /03L-0:on 831225,low Nitrogen Pressure Alarm Received on Control Rod Scram Accumulators 2C11-18-43 & 2C11-26-43.Cause Unknown.Accumulators Serviced W/Nitrogen & Returned to Svc
05000346/LER-1983-073-03, /03L-0:on 831219,containment Air Sample Return Valve CV5011E Failed to Close Electrically.Cause Unknown. Valve Cycled Three Times Smoothly W/Normal Running Currents. Operator & Starter Checked
05000271/LER-1983-005-01, /01P-0:on 830203,while Attempting to Reduce Flow Through Nitrogen Makeup line,V-16-20-20 & 22B Failed to Close.Cause Unknown.No Attempt Made to Inspect or Repair Due to Questions on Acceptability of Manual Isolation
05000334/LER-1983-040-03, /03L-0:on 831213,chemical Addition Pump Discharge Valve MOV-QS-1048 Failed to Close Electrically as Required by Tech Spec 3.6.2.3.Caused by Faulty Torque Switch. Compression Spring Replaced
05000280/LER-1982-117-03, /03L-0:on 821129,specific Activity Samples of RCS Indicated Dose Equivalent I-131 Level Greater than Tech Spec Limit.Caused by Fuel Element Defect in Reactor Core. Accelerated Sampling Frequency Implemented
05000346/LER-1982-060-03, /03L-0:on 821111,during Performance of ST 5031.14, Discovered Ventilation Duct Chase 48 Power Supply in Steam & Feedwater Rupture Control Sys Channel 2 Failing at 1-volt/h.Caused by Component Failure.Channel 2 de-energized
05000334/LER-1982-016-03, /03L-0:on 820427,turbine Auto Stop Oil Pressure switch,PS-TB63-5AST,found Inoperable & Trip Setpoints for PS-TB63-4AST & 6AST Found Out of Spec.Caused by Lug Blocking Trip Mechanism & Instrument Drift,Respectively
05000416/LER-1983-039-99, /99X-0:on 830112,during Cold Shutdown,Halon Panel 1H13P911 Detector a Alarmed & Would Not Reset.Hourly Fire Watch Established.Corrective Maint Underway
05000416/LER-1983-034-03, /03L-0:on 830129,fire Door 1A106 Alarmed on Supervision Sys & Would Not Reset.Caused by Failure of Lock/Latch Mechanisms.Lock/Latch Mechanisms Replaced & Doors Returned to Svc
05000237/LER-1983-066-03, /03L-0:on 830918,MSIV 2D 2.5 Closure Time Exceeded Tech Spec Requirement of 3 to 5 S.Caused by Timing Mechanism Out of Adjustment.Mechanism Adjusted
05000325/LER-1983-036-03, During Reactor Startup, Control Power Supply Fuse on Motor Operator Breaker of Sys Flow Control Valve 1-E11-F068 Blew.Caused by Broken Open Position Lamp.Fuse Replaced
05000306/LER-1983-022-03, /03L-0:on 830909,steam Flow Transmitter Found Out of Calibr Low by 1%.Cause Unknown.Transmitter Returned to Vendor for Analysis.Rosemount Model 1153HA6 Differential Pressure Transmitter Replaced
05000325/LER-1983-033-03, /03L-0:on 830829,during Power Operation,Discovered Primary Containment Isolation Sys Reactor Low Level 2 Instrument 1B21-LTM-N024B-1 Showing Higher Level than Expected.Caused by Instrument Drift
05000254/LER-1983-012-01, /01T-1:on 830310,reactor Operator Inadvertently Inserted Control Rods in Reverse Order.Caused by Personnel Error.Control Room Personnel Will Be Instructed in Proper Procedures
05000346/LER-1983-042-03, /03L-0:on 830801 & 06,main Steam Line Room Doors 601 & 602 Found Open & Unattended.Caused by Personnel Error. Personnel Counseled
05000333/LER-1983-019-03, /03L-1:on 830501,low Pressure Coolant Injection Sys Side B Independent Power Supply Inverter Indicated Minor Trouble Alarm.Caused by Failed Gate Firing Module Printed Circuit Board.Board Replaced
05000366/LER-1983-068-03, /03L-0:on 830824,use of P1 Computer Program,Core Max Fraction of Limiting Power Density Exceeded Fraction of Rated Thermal Power by 2%.Caused by High Core Flux Peak Due to Control Rod Pattern
05000321/LER-1983-076-03, /03L-0:on 830806,w/reactor Cleanup Pumps Out of Svc,Determined That Conductivity Monitor Failed Downscale. Caused by Plugged Monitor Sample Line.Pumps Returned to Svc
05000366/LER-1983-075-03, /03L-0:on 830802,hydrogen Recombiner Suction Isolation Valve 2T49-F002A Would Not Pressurize.Caused by Normal Wear & Tear.Valve Repaired
05000254/LER-1983-026-03, /03L-0:on 830705,while Performing Main Steam Line High Flow Calibr,Discovered That Pressure Switch DPIS 1-261-2J Tripped at 146% Steam Flow.Probably Caused by Setpoint Drift.Instrument Recalibr
05000316/LER-1983-057-03, /03L-0:on 830624,stop Valve for Steam Generator 21 (2-MRV-210) Failed to Meet Tech Spec Closure Time.Cause Undetermined.Retest of Valve on 830709 Acceptable
05000237/LER-1983-050-03, /03L-0:on 830617,snubber 42 on Steam Line a Found to Have Loose Pipe Clamp Which Had Dropped 2 Inches from Normal Position.Probably Caused by Inadequate Tightening of Clamp Bolts During Original Installation
05000255/LER-1983-044-01, /01T-0:on 830625,during Planned Power Reduction, Sample from Safety Injection Tank T-82D Showed Boron Concentration Below Tech Specs.Caused by Minor Leak Past Loop Check Valve.Valves Will Be Inspected
05000324/LER-1983-076-03, /03L-0:on 830812,primary Containment Atmosphere Oxygen Analyzer 2-CAC-AT-1259-2,showed Drywell Oxygen Concentration Approx 1% Higher than Redundant Analyzer. Caused by Analyzers Out of Calibr
05000366/LER-1983-029-03, Two Safety/Relief Valve Position Primary Indicators 2B21-N301A & C Found to Actuate Above Tech Spec Limits.Caused by Setpoint Drift.Amend 33 to License NPF-5 Changed Tech Spec Limits
05000346/LER-1983-030-03, /03L-0:on 830614,during Change in ECCS Coil Assembly 1,floor Plugs Forming Part of Negative Pressure Boundary & Fire Barriers Removed.Caused by Personnel Error. Floor Plugs Reinstalled & New Procedure Written
05000321/LER-1983-037-03, /03L-0:on 830510,while Performing Hydrogen & Oxygen Analyzer Instrument Procedure (HNP-1-3882),hydrogen Analyzer (IP33-N002A) Indicated Incorrectly.Caused by Failed Current Transmitter.Transmitter Replaced
05000325/LER-1983-016-03, /03L-0:on 830425,routine Surveillance Revealed Electrolyte Levels of 125-volt Dc Div I & II Battery Cells Out of Allowable Level Band Mark.Caused by Changes in Ambient Battery Room Temps
05000366/LER-1983-025-03, /03L-0:on 830414,during Turbine Bldg Area Temp Functional Test & Calibr,Monitor 2U61-R002 Found Out of Calibr.Caused by Setpoint Drift of Five Temp Switches & Inoperability of One Switch.Monitor Replaced
05000333/LER-1983-014-03, /03L-0:on 830404,during Normal Plant Operations, Four Cells of B Side Station Battery Found to Have Through Wall Cracks Leaking Electrolyte.Caused by Mishandling of Cells During Original Installation.Cells Replaced
05000244/LER-1983-012-03, /03L-1:on 830323,individual Doors for Personnel Hatch Had Higher Leak Rate than Allowed.Caused by Incorrect Maint Procedure on 821007 Requiring Only Door Seal Leak Testing.Procedure Revised.Other Procedures Reviewed
05000265/LER-1983-011-03, /03L-0:on 830711,circuit Breaker Overloads Tripped Repeatedly While Attempting to Open Valve Mo 2-1001-36B from Control Room.Caused by Excessive Close Torque Setting. Overloads Replaced & Torque Decreased
05000366/LER-1983-054-03, /03L-0:on 830713,offgas post-treatment Monitor 2D11-K615B Indicated Downscale.Caused by Failure of Scintillation Detector.Offgas post-treatment Monitor Replaced & Returned to Svc
05000346/LER-1983-012-01, Operating Practice of Requiring One ECCS Room Cooler to Be Valved Into Svc in Each ECCS Room Less Conservative than Updated FSAR Assumptions. Caused by Lack of Procedural Control.Fsar Reviewed
05000333/LER-1983-016-03, During Surveillance Testing on D Max Stillwater Level High Radiation Monitor, Setpoint of high-high Trip Found Below Tech Spec Limit. Caused by Instrument Drift.Setpoint Adjusted
05000267/LER-1983-016-03, /03L-0:on 830331,two Class 1 Hydraulic Shock Suppressors Found Inoperable.Caused by Fully Extended Snubbers,Due to Thermal Pipe Movement.One Snubber Adjusted & Other Replaced
05000249/LER-1983-015-03, /03L-0:on 830406,during Normal Operation W/Dis 287-1 in Progress,Pressure Switch Ps 3-1554 F Would Not Operate at Required Pressure.Caused by Plugged Instrument Snubber.Snubber Cleaned & Switch Replaced
05000325/LER-1983-017-03, /03L-0:on 830326-28 & 0402,listed Control Rods Had No Indications for Identified Positions.Caused by Loose Prototypic Inlet Piping Connectors in Each Rod Attributed to Undervessel Work.Plant Mods Scheduled
05000249/LER-1983-014-03, /03L-0:on 830405,main Steam Line Log Radiation Monitor 3A Experienced Loss of High Voltage Power Causing Monitor to Go Downscale.Caused by Burned Out Resistor on High Voltage Power Supply.Monitor 3A Replaced
05000271/LER-1983-008-03, /03L-0:on 830319,testing Revealed Actual Relief Setpoint on Main Steam Relief Valve to Be Out of Tech Spec Limit.Setpoint Drift Result of Excessive Pilot Valve Leakage.Relief Valve Being Rebuilt & Recalibr
05000321/LER-1983-038-03, /03L-0:on 830322,inspectors Discovered I Beam in Torus Room Supported by C Clamps,Contrary to Tech Spec Requirements.Cause Unknown.Clamp Removed
05000237/LER-1983-021-03, /03L-0:on 830321,diesel Generator Recirculating Lubricating Oil Pump Found Running W/No Pressure.Caused by Loosening Allen Screws.Pump Repaired & Procedure Modified
05000364/LER-1983-019-03, /03L-0:on 830404 & 19,rod Control Sys Declared Inoperable Upon Receipt of Failure Alarm on Power Cabinet 2AC.Following Second Occurrence,Phase Control Card B2 Replaced
05000361/LER-1983-033-03, /03L-0:on 830315,pilot Flames of Train a & B Toxic Gas Isolation Sys Butane Monitors Extinguished.Caused by Low Pressure in Single Hydrogen Supply Bottle.Bottle Replaced
05000293/LER-1983-013-01, /01T-0:on 830403,field Breaker for B Recirculation Pump Motor Generator Set Did Not Trip While Being Removed from Svc for Maint.Caused by bound-up Mechanism Preventing Breaker Opening.Breaker Linkages Lubricated
05000324/LER-1983-024-03, /03L-0:on 830321,during Routine Channel Check, Discrepancies in Level Indication of Reactor Level Instrument 2-B21-LT-NO17D-1 & Redundant Instrument Found. Caused by Small Stem Packing Leak.Leak Repaired
05000346/LER-1983-036-03, /03L-0:on 830715,safety Features Actuation Signal Channel 4 Containment Radiation Monitor RE2007 Failed Low. Monitor Also Inoperable on 830721 Due to Spiking.Exact Cause Unknown
05000334/LER-1983-009-03, /03L-0:on 830311,containment Vacuum Pump CV-P-1B Flow Rate Found Less than Tech Spec Min & Declared Inoperable.Caused by Sticking of Sliding Carbon Vanes Due to Corrosion Products in Rotor Slots.Pump Replaced
05000364/LER-1983-021-03, /03L-0:on 830411,instrumentation Channel Associated W/Refueling Water Storage Tank Water Level Indicator LI-4075A Declared Inoperable Due to Low Indication.Cause Not Determined
05000267/LER-1983-010-03, /03L-0:on 830302,during Release of Radioactive Liquid Effluent from Reactor Bldg Sump,Overflow from Liquid Waste Sump Drained Into Reactor Bldg Sump.Caused by Personnel Error.Release Terminated
05000361/LER-1983-020-03, /03L-0:on 830224,during Mode 5,latch for Door C3-67 Between Control Room & Cable Riser Gallery Discovered Jamming.Caused by Excessive Use.Emergency Maint Performed Per Special Order 83-18
05000282/LER-1983-003-03, /03L-0:on 830228,during Review of Surveillance program,4-kV Voltage & Frequency Test Sp 1015 Found Not Completed by Due Date.Caused by Personnel Oversight.Test Performed.Personnel Counseled
05000286/LER-1983-004-03, /03L-0:on 830604,leak Observed at elbow-to-pipe Weld on Charging Pump 31 Relief Line 210 Downstream of Relief Valve RV231.Cause Not Stated.Valve 231 Replaced & Pump Returned to Svc
05000324/LER-1983-058-03, /03L-0:on 830606,HPCI Sys Steamline Area Differential Temp High Logic a Isolation Signal Occurred, Causing Automatic Closure of HPCI Sys Steam Supply Outboard Valve PCIV 2-E41-F003
05000306/LER-1983-004-03, /03L-0:on 830303,during Surveillance Testing, Excessive Leakage from Maint Airlock Measured.Caused by Deterioration of Grafoil Packing at Outboard Upper Shaft Seal.Packing Tightened
05000416/LER-1983-098-03, /03L-0:on 830718,air Start Solenoid Valve F508C Failed to Operate,Resulting in Diesel Generator Failure to Start.Caused by Open Circuit Coil on Solenoid.Valve Replaced
05000267/LER-1981-047-03, During Testing,One of 12 Helium Circulator Seal Malfunction Pressure Differential Switch Units Tripped Outside Limits.Caused by Dirt Accumulation in Electrical Switch.Switch Replaced
05000261/LER-1983-002-03, /03L-0:on 830215,safety Injection Pump a Tripped After Being Started for Routine Filling of Accumulators. Caused by Faulty Pump Breaker.Overcurrent Trip Device Replaced.Evaluation of Event Continuing
05000366/LER-1983-031-01, /01T-0:on 830530,while Performing Fuel Movement Operation Procedure (HNP-2-9302),11 Fuel Assemblies Discovered Loaded Out of Proper Core Orientation.Caused by Personnel Error.Individual Counseled
05000254/LER-1983-022-03, /03L-0:on 830523,RCIC Steam Supply Valve MO-1-1301-16 Did Not Give Open Position Indication When Operated from Control Room.Valve Found Open.Caused by Loose Wire on Open Limit Switch
05000334/LER-1983-015-03, /03L-0:on 830524,during Normal Power Operation, Relay 5I-VD106X Experienced Spurious Actuation,Causing Inadvertent Isolation of Emergency Bus 1DF from Normal Supply.Caused by Personnel Error
05000346/LER-1983-005-03, /03L-0:on 830127,acceptance Criteria of Containment Airlock Seal Leakage Surveillance Test ST 5061.05 Did Not Agree W/Tech Spec Surveillance Requirements.Caused by Procedure Deficiency
05000254/LER-1983-020-03, /03L-0:on 830510,while Performing Monthly Exercise Qos 1600-1,Div II Indicating Lights for Vacuum Breaker 1-1601-33F Did Not Operate When Valve Exercised.Caused by Slight Binding in Vacuum Breaker Main Shaft
05000334/LER-1983-003-03, /03L-0:on 830110,low Voltage Condition Logged on Battery Bus 1.Caused by Open Circuit in Charge Collector Resistor Preventing Charger Control in Voltage Circuit from Properly Regulating Charger Output Voltage
05000346/LER-1983-021-03, /03L-0:on 830502,operator Found Fuel Handling Access Corridor Door 406 Ajar.Caused by Failure of Closure Mechanism.Closure Mechanism Adjusted to Force Door Closed
05000237/LER-1983-041-03, /03L-0:on 830506,calibr of Drywell Pressure Switch Dis 1500-4,relay 1530-299 Failed to Pick Up When Pressure Switch 1501-620 Functionally Tested.Caused by Loose Connection in Wiring Circuitry
05000237/LER-1983-032-03, /03L-0:on 830425,during Unit Startup,Reactor Water Sample Not Pulled Every 4 H Per Tech Spec Requirements. Caused by Lack of Communication Between Technicians During Shift Change & Failure to Use Flashing Sign
05000265/LER-1983-007-01, /01T-0:on 830509,while Reviewing out-of-svc Documentation,Discovered That Control Rod Drives (CRD) 38-07 & 46-55 on Unit 2 & 06-43 on Unit 1 Made Inoperable W/O Verifiying Shutdown Margin or Insertion
05000272/LER-1982-016-03, /03L-0:on 820326,gaseous Release Initiated from Waste Gas Sys.Caused by Failure of Control Room Operator to Properly Perform Operating Instruction Resulting in Incorrect Vent Monitor Alignment.Ets Limits Not Exceeded
05000361/LER-1982-052-03, /03L-0:on 820419,during Routine Shift Surveillance,Channel B Ammonia Analyzer of Toxic Gas Isolation Sys Was Declared Inoperable.Caused by Instrument Drift.Analyzer Repaired & Recalibr
05000317/LER-1982-013-03, /03L-0:on 820316,w/charging Pump 12 Out of Svc Awaiting Maint,Discharge Relief Valve of Charging Pump 13 Lifted & Remained Open,Rendering Pump Inoperable.Caused by Relief Valve Setpoint Drift.Test Will Be Conducted
05000285/LER-1978-034-03, /03L-0 on 781026:repeated Tripping of Stack Particulate Process Monitor.Caused by Trip Set in Accordance W/Tech Specs Table 2-1 at 9.6x10-2,rather than More Conservative Release Rates 2x10-3
05000311/LER-1983-010-03, /03L-0:on 830126,during Shutdown Operations, Control Air Header 21 Isolated & Tagged for Leak Rate Testing.Porv 2PR1 Closed Resulting in Loss of RCS Vent Path. Caused by Surge in Header 22 Due to Failed Valve
05000254/LER-1983-008-03, /03L-0:on 830210,during Functional Test Qis 35-2, Fuel Pool Radiation Monitor 1-1705-16A Failed to Trip Upscale.Caused by Instrument Calibr Drift.Monitor Recalibr & Function Test Completed Satisfactorily
05000281/LER-1983-003-03, /03L-0:on 830202,w/unit at 100% Power & Emergency Diesel Generator 3 Out of Svc for Maint,Containment Vacuum pump,2-CV-P-1A,failed to Develop Flow.Caused by Binding of Sliding Vanes in Pump Rotor.Pump Replaced W/Shop Spare
05000333/LER-1979-029-03, /03L-0 on 790518:during Snubber insp,14 Snubbers Required Some Work & Six Snubbers Were Determined to Be Potentially Inoperable.Snubbers Removed & Tested.Two Snubbers Failed Test & Were Declared Inoperable
05000311/LER-1983-007-01, /01T-0:on 830210 & 11,during Routine Surveillance Testing,Two Steam Generator Snubbers Failed to Meet Acceleration & Bleed Test Requirements.Caused by Aging of Snubber Piston Seal Rubber Matl.Seals Will Be Rebuilt
05000346/LER-1983-017-03, /03L-0:on 830411,spent Fuel Pool (SFP) Level Verification Surveillance Test Ordered Later than Tech Spec Requirement.Caused by Personnel Error.Sfp Level Verified. Memo on Schedules Planned
05000416/LER-1983-026-03, /03L-0:on 830128,fire Doors 0C220 & 1A211 Alarmed on Supervision Sys & Would Not Reset.Cause Not Determined. Fire Detectors Verified Operable & Hourly Fire Watch Established
05000346/LER-1983-004-03, /03L-0:on 830119,during Cooldown,Jumper on Pressure Switch PSH-RC2B4 Had Been Left in Place Since 820823.Caused by Lack of Administrative Control & Design Error.Procedure Rewritten to Provide Adequate Switch
05000361/LER-1983-007-03, /03L-0:on 830111,iodine Removal Sys Valve 2HV-9398 Failed Tech Spec Surveillance Test & Was Declared Inoperable.Caused by Misaligned Upper Limit Switch.Limit Switch Readjusted & Valve Returned to Svc
05000334/LER-1983-001-03, /03L-0:on 830102,fire Barrier Penetration from East Cable Vault Ceiling to Containment Purge Duct Room Floor Discovered Unsealed.Caused by Area Differential Pressure.Both Penetration Ends Will Be Taped
05000333/LER-1983-006-03, /03L-0:on 830110,Wyle Labs Notified Util That as-found First & Second Actuations of Relief Valve D Were Out of Tech Spec Tolerances of 1,094 to 1,116 Psig.Cause of Setpoint Drift Unknown.Problem Under Investigation
05000361/LER-1983-008-03, /03L-0:on 830114,during Mode 1,Train B post-LOCA Hydrogen Monitor 2AET-8111-2 Failed to Meet Channel Functional Test.Caused by Faulty Detector.Detector Replaced. Monitor Returned to Svc
05000373/LER-1983-002-03, /03L-0:on 830121,functional Testing of HPCS Keep Filled Pressure Alarm Not Performed Monthly from 820415 to 0922.Caused by Personnel Error.Tech Spec Review Will Be Completed by 830401
05000293/LER-1983-001-03, /03L-0:on 830105,inboard Reactor Water Sample Isolation Valve AO-220-44 Did Not Close.Cause Will Be Investigated During Next Outage
05000265/LER-1983-003-03, /03L-0:on 830110,traversing Incore Probe 4 Ball Valve Failed to Fully Close as Travelling Incore Probe Returned to Shield.Caused by Crud Buildup in Internals, Allowing Valve to Only Partially Close.Ball Valve Cleaned
05000324/LER-1982-132-03, /03L-0:on 821217,during Nitrogen Makeup to Primary Containment,Core Auxiliary Cooling Sys 1-inch Drywell Inlet PCIV 2-CAC-V48 Discovered Leaking by Closed Valve Seat. Cause Undetermined.Containment Integrity re-established
05000333/LER-1983-001-04, /04T-0:on 821230,number of Fish Impinged During 24 H Period Exceeded 20,000.Caused by Bad Weather Conditions Experienced During Sampling.Sampling Continued Until Fish Count Fell Below 20,000
05000254/LER-1983-004-03, /03L-0:on 830109,containment Cooling Loop a Taken Out of Svc for Preventive Maint on RHR 1A Hx.New Gaskets for Inner Head & Drain Line of HX Installed to Repair Small Leaks
05000293/LER-1982-057-03, /03L-0:on 821213,during Routine Startup from Outage,Outboard MSIV AO 203-2C Did Not Close within Tech Spec Limit.Caused by Malfunctioning four-way Control Valve. Valve Replaced.Timing Dash Pot Adjusted
05000293/LER-1982-053-03, /03L-0:on 821110,ground Fault Alarm Observed on 125-volt Dc Battery Circuit & Traced to Limit Switch Circuitry for MOV2301-3.Caused by Valve Packing Steam Leakage.Packing Tightened for short-term Fix
05000267/LER-1982-043-03, /03L-0:on 821027 & 28,average Pcrv Cooling Water Sys Inlet & Outlet Temps Fell Below 100 F.Caused by Insufficient Heat to Maintain Loop Averages W/Both Loops in Svc.Auxiliary Heat Obtained & Operators Reinstructed
05000316/LER-1982-092-03, /03L-0:on 821109,during Normal Operation,Auxiliary Cable Vault (Zone 11) Experienced Inadvertent Carbon Dioxide Discharge & Pyralarm Detector Alarming.Caused by Water Entering Base.Detector & Base Replaced
05000346/LER-1982-059-03, /03L-0:on 821108,containment post-accident Radiation Monitor,Channel 2 Read Low.On 821116 & 22 Equipment Fail Alarm Received.Caused by Failed High Voltage Power Supply Board.Board Replaced & Declared Operable
05000289/LER-1982-015-03, /03L-0:on 821103,1.5-inch Irregular Diameter Hole Found in Floor Fire Barrier Penetration Seal.Caused by Unsealed Opening.Fire Watch Posted.Seal Repaired on 821109
05000281/LER-1982-069-03, /03L-0:on 821104,charging Pump Svc Water Pump 2-SW-P-10B Experienced Loss of Suction Pressure.Caused by Insufficient Npsh.Pump Vented to Restore NPSH
05000361/LER-1982-176-01, /01T-0:on 820710,independent Verification Not Performed on Reactor Trip Circuit Breakers 4,6 & 7 Undervoltage Trip Mechanism Operability After Maint.Caused by Personnel Oversight.Maint Program Revised
05000321/LER-1983-027-03, /03L-0:on 830304,core Max Fraction of Limiting Power Density Found Greater than Fraction of Rated Core Thermal Power.Caused by Rod Out Block Preventing Proper Rod Pattern.Tech Spec Rev Proposed
05000267/LER-1983-007-03, /03L-0:on 830215,instrument Power Invertor 1B Failed.Caused by Blown 150 Amp Fuse.Reactor Manually Scrammed,Instrument Bus 2 re-energized & Fuse Replaced
05000293/LER-1983-008-03, /03L-0:on 830214,deviation from Tech Spec Fire Barrier Requirements Found During Conversion of Instrumentation & Control Lab to Ofc Space.Caused by Failure to Change Existing Conditions During Retrofit
05000362/LER-1983-017-03, /03L-0:on 830205,tank Vol & Pressure for Safety Injection Tank 3T-008 Found Outside Allowable Limits.Caused by Leakage Past Header Isolation Valve 3HV-9324 & Backflow Through Outlet Check Valve MU040
05000254/LER-1983-011-03, /03L-0:on 830225,during Low Condenser Vacuum Calibr & Functional Tests,Pressure Switch PS-1-503A Tripped at 20.9 Inches Hg Vacuum.Caused by Setpoint Drift.Switch Recalibr & Functionally Tested
05000254/LER-1983-007-03, /03L-0:on 830214,suppression Chamber Nitrogen Purge Valve AO-1-1601-56 Failed to Isolate During Maint on Drywell High Radiation Monitors.Caused by Failure of Solenoid Pilot Valve.Valve Replaced
05000261/LER-1981-031-01, /01T-0:on 811201,pressurizer Power Operated Relief Valve Block Valves Were Determined Not to Meet Design Specs. Valve Motor Operators Failed to Shut Valves Completely Following 811130 Transient.Block Valves Closed Manually
05000315/LER-1982-100-03, /03L-0:on 821105,during Normal Operation,Fire Door 437 Found Inoperable.Caused by Door Scraping on Stair Step.Clearance Between Door & Step Improved
05000373/LER-1982-141-03, /03L-0:on 821102,RCIC Inboard Testable Check Valve IE51-F066 Failed to Indicate Closed.Cause Still Under Investigation W/Vendor.Alternative Limit Switch Configurations Being Evaluated
05000373/LER-1982-142-03, /03L-0:on 821102,radwaste Valve OWL067 Did Not Fully Close When Tripped W/Simulated Radwaste Discharge hi-hi Trip Signal.Caused by Fouling of Valve Internals W/ Foreign Matls.Valve Cleaned
05000333/LER-1982-049-03, /03L-0:on 821027,during Tech Spec Surveillance Requirement Review,Scram Discharge Vol Vents & Drains Not Cycled on Quarterly Basis.Caused by Supervisory Personnel Error.Addl Surveillance Procedure Developed
05000293/LER-1982-052-03, /03L-0:on 821028,recirculation Pump a MG Set Inadvertently Tripped While Troubleshooting Ground Indication for 125-volt Dc Circuit.Caused by Inadequate Info Available to Troubleshooters.Info Upgraded
05000311/LER-1982-127-03, /03L-0:on 821020,RCS Water Inventory Not Performed within Time Limits.Caused by Personnel Oversight & License Inadequacy.Surveillance Completed,Personnel Counseled & License Change Request Submitted
05000346/LER-1982-055-03, /03L-0:on 821021,safety Features Actuation Sys Channel 4 Radiation Monitor RE-2007 Failed Low.Cause Unknown.Detectors Replaced
05000293/LER-1982-051-03, /03L-0:on 821012,offsite Power Lost.Caused by Accumulation of Salt on Switchyard Insulators Due to Ocean Storm.Breakers Opened & Could Not Be Reclosed.Salt Washed from Insulators & Breakers Reclosed
05000416/LER-1982-183-99, /99X-0:on 821222,smoke Detection Zone Covering Auxiliary Bldg Corridor Area Alarmed & Would Not Reset.No Smoke or Fumes Present.Zone Found Functionally Operable & Alarms Reset
05000416/LER-1983-025-03, /03L-0:on 830124,auxiliary Bldg Equipment Hatch on Elevation 166 Ft Removed.Caused by Deliberate Personnel Action to Allow Transport of Neutron Source Into Containment.Equipment Hatch Replaced
05000416/LER-1983-008-99, /99X-0:on 830104,one Door in Control Bldg (0C409) & One Door in Auxiliary Bldg (1A203) Blocked Open for Planned Maint Activities.Hourly Fire Watch Established
PY-CEI-NRR-1417, Suppls 900717 & 1221 Responses to NRC Bulletin 90-001. Potential Loss of Fill-Oil in Rosemount Transmitters
05000265/LER-1982-021-03, /03L-0:on 821015,turbine Pressure Generator Load Reject & Stop Valve Bypass Alarm Would Not Clear Due to Closing of Relay 2-590-123B,rendering Reactor Protection Sys B1 Subchannel Inoperable.Caused by Personnel Error
05000311/LER-1982-123-03, /03L-0:on 821010,svc Water Flow to Containment Fan Coil Unit Was 2,400 Gpm Rather than Required 2,500 Gpm. Caused by Low Setpoint on Flow Control.Controller Tested & Setpoint Readjusted to Proper Flow
05000293/LER-1982-042-03, /03L-0:on 820929,during Timing Surveillance,Hpci Torus Suction Valve MO-2301-35 Failed to Operate.Caused by Open Field Winding on Operating Motor.Motor Rewound,Valve Tested for Binding & Returned to Svc
05000247/LER-1982-042-03, /03L-0:on 820923,one of Two Level Alarm Setpoints Found Above Max Level Per Tech Specs.Caused by Level Alarm Bistable Setpoint Drift.Setpoint Reset to Required Value. Surveillance Frequency Increased
05000348/LER-1982-057-03, /03L-0:on 821001,during Reactor Coolant Pump Bus Reactor Trip Undervoltage Relay Calibr,Reactor Coolant Pump 1A Undervoltage Relay 27-3 Discovered Out of Spec.Caused by Setpoint Drift.Setpoint Adjusted
05000334/LER-1982-041-03, /03L-0:on 821001,chlorine Detector CLA-VS-101C W/Zero Drip Rate & Dry Electrode Found During Routine Shift Surveillance.Caused by Foreign Matl Blocking Reservoir Orifice.Orifice Cleaned Out W/Wire
05000333/LER-1982-048-03, /03L-0:on 821020,number 4 Plant 115-kV Lines Removed from Svc for 2-h.Caused by Extension Cord Being Dropped Across Two Phases of Line.Line de-energized,fault Cleared & Line re-energized
05000334/LER-1982-033-03, /03L-0:on 820911,operators Unable to Reclose Steam Supply Trip Valve TV-MS-105B of Turbine Driven Auxiliary Feedwater Pump FW-P-2.Caused by Washer Lodged in Valve Trim. Line Isolated
05000321/LER-1982-084-03, /03L-0:on 820916,channel B Main Steam Line Radiation Monitoring Instrument Failed.Cause Unknown.Spare Instrument Installed,Calibr & Tested
05000247/LER-1982-032-01, /01T-0:on 820817,blowdown Outer Isolation Valve PCV 1215A Failed Closed Due to Failure of Solenoid Valve SOV 1315A.Caused by Open Circuit in Pilot Solenoid Valve SOV 1315A Coil.Coil Replaced
05000311/LER-1982-096-03, /03L-0:on 820831,containment Fan Coil Unit 23 Declared Inoperable When Operator Received Indication of Low Svc Water Flow.Caused by Silt Buildup in Cooling Coils.Flow Control Valve Cycled & Unit Tested Satisfactorily
05000293/LER-1982-028-03, /03L-0:on 820804,during Recovery from Scram, MOV 220-2 Indicated Intermediate Position.Caused by Worn Limit Switch Components in Limitorque Actuator.Valve Stem Nut Found Loose from Stakes.Components Replaced
05000293/LER-1982-024-01, /01T-0:on 820813,HPCI Tripped Due to High Reactor Water Level.Caused by Failure of HPCI Gland Seal Condenser Gasket Wetting HPCI Control Circuitry.Circuits Dried & Calibr.Gasket Repaired Using Improved Version of SIL-129
05000293/LER-1983-003-03, /03L-0:on 830113,during Surveillance Test,Reactor Water Cleanup Sys High Flow Isolation DPIS-1243 Found Out of Calibr.Caused by Loose Switch Plant Locking Screw Which Allowed Setpoint to Drift.Setpoint Recalibr
05000267/LER-1983-002-03, /03L-0:on 830104,seven Unsampled Releases Made from Reactor Bldg Sump on 821221 & 22.Caused by Personnel Error.Daily Sample Taking Resumed on 821223.Responsible Personnel Retrained
05000293/LER-1982-023-01, /01T-0:on 820813,during Personnel Access to Torus Room,Removable Hand Rail Fell Against Steam hi-flow Dpis(S) Resulting in Scram.Caused by Personnel Error. Hand Rails Removed
05000267/LER-1983-003-03, /03L-0:on 14 Separate Occasions,Total Primary Coolant Oxidants Exceeded Acceptable Limits.Oxidant Offgassing Caused by Increasing Temps During Normal Reactor Startup & Rise to Power.Oxidant Concentration Reduced
05000267/LER-1982-047-03, /03L-0:on 821201,during Surveillance Testing on Loss of Bearing Water Plant Protection Sys Circuitry for Circulator C,Logic a Module CT2 Found Inoperable.Caused by Failure of Chip Z-32 in Logic Module CT-2A2.Chip Replaced
05000324/LER-1982-137-03, /03L-0:on 821206,during Operability Test of Remote Shutdown Panel,Rhrsw D/P Transmitter 2-E11-POT-N002BX Did Not Respond to Test Input Signal.Caused by Failed Transmitter Differential Pressure Unit.Transmitter Replaced
05000333/LER-1982-055-03, /03L-0:on 821214,turbine Steam High Flow Containment Isolation Switch 13-DPIS-84 Setpoint Found Less Conservative than Tech Specs.Caused by Instrument Drift. Setpoint Adjusted to within Required Value
05000219/LER-1978-022-03, /03L-0 on 781017:during Routine Surveillance Test of Standby Gas Treatment Sys,The Sys II Discharge Valve Failed to Open,Due to Stuck Solenoid in Control Air Supply to Operator for V-28-30
05000293/LER-1978-019-03, Inboard MSIV-AO-203-1D Declared Inoperable & Outboard MSIV-AO-203-2D Secured in Close Condition When MSIV-AO-203-1 Disc Separated from Stem. Caused by High Cycle Bending Fatigue
05000267/LER-1978-032-03, /03L-0:on 780928,surveillance Check of Fixed Low Flow Alarm Bistables for Primary Coolant Dew Point Moisture Monitors Not Performed.Caused by Misinterpretation of Surveillance Requirements
05000334/LER-1982-058-03, /03L-0:on 821122,while Performing Power Range Neutron Flux Channel N-NI 42 Quarterly calibr,1.84 Rate Trip Time Constant Discovered.Caused by Instrument Drift. Time Constant Adjusted to 2.24
05000254/LER-1982-025-03, /03L-0:on 820907,1/2A Standby Gas Treatment Train Heater Found Tripped During Procedure Qop 020-1.Caused by Conservative Switch Setting Due to Inadequate Setpoint Differences.Heater Trip Reset
05000311/LER-1982-103-03, /03L-0:on 820904,while Running Auxiliary Alarm Summary,Control Breaker Alarm Observed for Containment Spray Pump 21.Caused by Opened 4 Kv Breaker Hl Contact.Breaker Racked Out & Pump Declared Operable
05000272/LER-1982-058-03, /03L-0:on 820809,steam Generator 12 Pressure Indication at Remote Shutdown Panel Failed Low.Caused by Transistor Failure in Instrument Power Supply.Failed Transistor Replaced
05000324/LER-1982-096-03, /03L-0:on 820814,review of Primary Containment Isolation Logic Revealed Failure to Meet Requirement to Have Low Condenser Vacuum Switches B21-PS-N056 (A-D) in Svc When Vessel Pressure Was Greater than or Equal to 500 Psig
05000272/LER-1982-055-03, /03L-0:on 820801,during Surveillance Testing of Fire Suppression Sys,Number 1 Fire Pump Would Not Start from Automatic Initiation.Caused by Failed Battery Charger Fuse.Fuse Replaced & Battery Charged
05000263/LER-1982-007-03, /03L-0:on 820726,while Attempting to Add Oil to Governor During Monthly Diesel Generator Test,Personnel Changed Adjustment of Governor Shutdown Solenoid.Caused by Personnel Error.New Governor Installed.Procedure Revised
05000254/LER-1982-012-01, /01T-0:on 820622,following Scram on Unit 2,1/2 Diesel Generator Tripped When a RHR Svc Water Pump Started. Caused by Underexcitation of Diesel Relays.Relays Removed Pending Design Change
05000272/LER-1982-035-99, /99X-0:on 820526 & 0603,fire Pump 2 Failed to Start.Apparently Caused by Control Circuit Malfunction. Investigation Underway.Hope Creek Fire Suppression Sys Will Be Used in Interim
05000311/LER-1981-021-03, /03L-0:on 810519,auxiliary Feedwater Tank Fell Below Min Operating Level.Caused by Personnel Error.When Tank Used as Water Supply for Steam Line Heatup,Supply to Tank Throttled Too Far to Compensate for Water Removed
05000305/LER-1982-024-03, /03L-0:on 820716,while at Full Power,Overpower Delta T Channel 3 Rod Stop Alarm Observed Cycling in & Out. Caused by Malfunction of Tavg Signal Conditioner Causing Channel to Drift.Spare Signal Box Installed & Calibr
05000272/LER-1982-047-03, /03L-0:on 820726,containment Plant Vent Monitor Sample Pump Found de-energized & Failed to Start.Supply Breaker Found Tripped.Cause Undetermined.Breaker Reset & Closed & Pump Sucessfully Started from Control Room
05000237/LER-1982-029-03, /03L-0:on 820712,HPCI Min Flow Valve 2-2301-14 Failed to Reclose After Opening.Caused by Control Wire Caught Under Torque Switch.Wire Secured Away from Torque Switch & Recycled to Verify Operability
05000334/LER-1981-019-01, /01T-0:on 810305,RHR Low Flow Alarm Actuated, Accompanied by Low Current on Operating Pump.Caused by Loss of Suction Pump During Reduction of RCS Level
05000338/LER-1978-108-03, /03X-1 on 781012:during Mode 1 Opers,At 100% Pwr, Feedwater Flow Transmitter FT-1496 on Feedwater Loop C Failed Low.Caused by Blown Fuse.Fuse Subsequently Replaced
05000338/LER-1978-115-03, /03L-0 on 781107:during 1-pt-134 Periodic Test, MOV-QS102A Would Not Return to Normal Closed Position Because of Dirty Contacts on Valves Torgue Switch.Contacts Were Cleaned
05000338/LER-1978-125-01, /01T-0 on 781130:noted That Emergency Diesel Generator Battery Racks Were Improperly Installed.Caused by Failure to Perform Requested Mods
05000346/LER-1982-037-03, /03L-0:on 820816,door 306 Failed to Close Properly,Due to Bent Bottom Seal Plate.Cause Unknown.Seal Plate Replaced to Allow Proper Door Operation
05000334/LER-1982-026-03, /03L-0:on 820725,during Investigation of Spurious Alarms from Subcooling Margin Monitor,Monitor Indicated All Eight Incore Thermocouples Spiking.Cause Unknown.Cable Connectors Cleaned
05000254/LER-1982-019-03, /03L-0:on 820713,during Calibr of Reactor Automatic Relief Valves,Controllers for Valves 1-203-3B, 3D & 3E Found to Trip at Pressures in Excess of Tech Spec Limits.Caused by Setpoint Calibr Below Limits
05000304/LER-1982-017-03, /03L-0:on 820708,during Hot Shutdown & After Taking MSIV 2B Out of Sequence,Msiv Drifted Open & Was Rendered Inoperable.Caused by Failure to Open Drain Valve. Signs Reminding Operators to Verify Drain Position Posted
05000324/LER-1978-075-03, /03L-0 on 781122:HPCI & RCIC Component Tests Were Overlooked Because Rescheduling Technique Provided No Clear Indication of Test Due Dates.Responsible Technician Reinstructed & Admin Operating Instruction AOI-5 Rev
05000334/LER-1982-027-03, /03L-0:on 820725,containment Vacuum Pump 1A Failed to Start While Performing Radcon Sample Procedure.Caused by Foreign Matl Jammed Between Rotor & Cylinder Bore.Pumps Will Be Run for 1-5 Minutes Daily
05000361/LER-1982-040-03, /03L-0:on 820719,control Room Emergency Chiller E-335 Tripped on High Bearing Temp.Caused by Faulty High Temp Bearing Alarm Module.Module Replaced
05000361/LER-1982-057-03, /03L-0:on 820720,condensate Storage Tank T-121 Water Level Fell Below Tech Spec Limit on Four Occasions. Caused by Inadequate Makeup Water Control to Tank.Tech Spec Change Initiated to Install Automatic Level Control
05000334/LER-1982-024-03, /03L-0:on 820718,during Startup,High Temp Alarm Came in on B Component Cooling Pump Bearing.Caused by Failure of Bearing Due to Pump/Motor Misalignment.Pump Vendor Contacted to Investigate Recurring Problem
05000361/LER-1982-084-03, /03L-0:on 820801,control Element Assembly 57 Slipped & Dropped in Excess of Tech Specs.Caused by Slow Operation of Grippers.Control Element Assembly Exercised, Oxide Deposits Removed W/Hydrazine & Circuits Modified
05000361/LER-1982-121-03, /03L-0:on 820920,condensate Storage Tank T-120 Water Level Fell Below Tech Spec Limit While in Mode 2. Caused by Inadequate Makeup Water Control.Corrective Actions Include Better Planning & Timely Water Transfer
05000361/LER-1982-102-03, /03L-0:on 820829,condensate Storage Tank T-121 Water Level Fell Below Tech Spec Limit.Caused by Inadequate Makeup Water Control to Tank & Too Restrictive Tech Spec Limit.Tech Spec Change & Automatic Level Control Proposed
05000334/LER-1982-022-03, /03L-0:on 820707,high Temp Alarm Received on Component Cooling Pump C Bearing.Caused by Pump/Motor Misalignment.Pump Bearing Replaced
05000317/LER-1978-049-03, /03L-0 on 781020:pump for Radiat Monitors Seized, Perhaps Due to Graphite Particles from Pump Being Deposited in Bearings.A Normal End of Life Failure.Code Pump Model 6
05000295/LER-1982-023-03, /03L-0:on 820713,during Normal Operation,Conponent Cooling Supply Valve to Pump Oil Cooler & Seal Plate Isolated.Cause Unknown.Component Cooling Alignment Procedure Changed to Require Complete Lineup Check
05000362/LER-1982-011-03, /03L-0:on 821217,during Mode 5,Zone 41 (Cable Spreading Room) Fire Detectors Removed from Svc to Permit Repair of Cables.Caused by Minor Cable Damage During Const Activities.Cable Replaced
05000259/LER-1982-046-03, /03L-0:on 820701-05,intermittent Trouble Alarms Received from Fire Protection Panel 1-25-311.Caused by Common Control Card Giving Intermittent Trouble Alarms. Circuit Board Replaced
05000267/LER-1978-025-01, /01X-1:on 780703,w/loss of Power to One of Two Redundant Logic Sys,Circulator Seal Malfunctioned & buffer- to-mid-buffer Trip of Helium Circulator Initiated.Caused by Logic Design Problem
05000302/LER-1978-025-04, /04T-0:on 781001,unplanned Radioactive Gas Release Occurred While Attempting to Place Miscellaneous Waste Evaporator in Svc.Caused by Procedural Inadequacy.Procedure Revised
05000220/LER-1978-033-03, /03L-0 on 780916:Surveillance Tests on Barton Model 289 Pressure Indicating Switches Showed Changes in Setpoints Due to Instru Drift.Rev Surveillance Test Scheds Now Adequate to Ensure Early Detection of Drifts
05000366/LER-1982-076-03, /03L-0:on 820629,torus Water Level Recorder Found Inoperable During Steady State Full Power Operation.Caused by Component Failure.Differential Pressure Transmitter Equalizing Valve in Valve Manifold Replaced
05000368/LER-1978-009-03, /03L-0 on 781006:during Post-Core Hot Functional Test,Prior to Initial Criticality,Mode 3 Oper,Emergency Feedwater Valve 2CV-1025-1,hydraulic Pump Motor Failed. Motor Was Replaced & Tested Successfully
05000416/LER-1982-029-03, /03L-0:on 820729,fuel Handling Area Ventilation Radiation Monitoring Pump Removed from Svc,Causing Limiting Condition for Operation.Caused by Incorrectly Written Work Order to Replace Rather than Repair Pump for Oil Leak
05000416/LER-1982-067-03, /03L-0:on 820910,smoke Detectors in Zone Covering Auxiliary Bldg Corridor Area Alarmed & Would Not Reset. Caused by Accumulation of Dust on Ionization Smoke Detector Combined W/High Sensitivity Setting.Detector Cleaned
05000416/LER-1983-013-99, /99X-0:on 830119,while in Cold Shutdown,Three Doors in Auxiliary Bldg Blocked Open to Support Plant Testing.Fire Watches Established.Testing Completed & Doors Closed on 830127
05000317/LER-1982-037-03, /03L-0:on 820701,pressurizer Level Deviated Slightly from Program Level by More than Plus/Minus 5% & Pressurizer Pressure Decreased Below 2,225 Psia to Changes in RCS Temp Necessitated by Startup Tests
05000249/LER-1982-026-03, /03L-0:on 820628,while Performing Dis 500-7, Pressure Switch Ps 504C Tripped at 402 Psig,Exceeding Tech Specs.Caused by Instrument Setpoint Drift.Switch Reset to Correct Setpoint
05000295/LER-1982-021-03, /03L-0:on 820620,penetration Pressurization Sys Zone 2 Could Not Be Repressurized to Over 32 Psig.Caused by Sheared Internal Float on Zone in-line Flowmeter,Resulting in Float Falling & Restricting Makeup Flow
05000267/LER-1982-022-03, /03L-0:on 820521,unplanned Radiological Releases from Reactor Bldg Exhaust Stack Occurred.Caused by Isolation Valve Closure Due to Personnel Error & Airborne Activity Entering Containment Tank Through Water Traps
05000280/LER-1982-024-01, /01T-0:on 820524,weld Leak on a Steam Generator Channel Head Drain Piping at 2-RC-159 Identified During RCS Integrity Test PT-11.Caused by Random Defect in Root Weld, Possibly Due to Split Pass
05000304/LER-1982-015-03, /03L-0:on 820525 & 29,condenser Offgas Radiation Monitor 2RE-0015 Failed Above Alarm Setpoint.Caused by Condensate Buildup Flooding Detector.Monitor Dried & Detector Replaced.Leakage Problem Under Investigation
05000304/LER-1982-014-03, /03L-0:on 820511,2A Steam Generator Pressure Comparator 2PC-516A/B Setpoint Found Drifting W/Max Error of -7.5%.Caused by Failure of Input Buffer Amplifier in Comparator.Comparator (Hagan 118) Replaced
05000295/LER-1982-018-03, /03L-0:on 820422,during Routine Calibr Surveillance,Radiation Monitor ORT-ARO8 for 592-ft Level of Auxiliary Bldg Found Lower than Tech Spec Limit.Cause Unknown.Procedures Being Revised
05000316/LER-1982-039-03, /03L-0:on 820424,low Flow Alarm Would Not Clear After Containment Air Particulate & Gaseous Radiation Monitor Sys (R-11/R-12) Sample Pump Stopped to Perform Required Sampling.Pump & Flowmeter Replaced
05000333/LER-1982-020-03, /03L-0:on 820427,rod Block Monitor B Did Not Indicate Proper Level & Caused Some Relay Chattering When Control Rods Were Selected for Movement.Caused by Failed 5-volt Dc Power Supply.Power Supply Repaired
05000324/LER-1982-051-03, Primary Containment Atmospheric Hydrogen analyzer,2-CAC-AT-1263-1,indicated 0% to 1.8% Change in Hydrogen Concentration in Drywell.On 820325,3% Change Noted.Caused by Erratic Potentiometer
05000267/LER-1982-015-03, /03L-0:on 820418 & 19,w/plant Operating at Power, Emergency Feedwater to Loop 2 Circulator Water Turbine Drives Were Isolated to Repair PV-21244 & PV-21244-1.Caused by Normal Wear,Resulting in Excessive Flow
05000334/LER-1982-015-03, /03L-0:on 820414,while Responding to Vital Bus 3 & Battery Operation Alarms,Power to Vital Bus Was Lost. Caused by Charger Output Exceeding Normal Ac Supply to Inverter Which Transferred Power to Dc Bus Source
05000272/LER-1982-023-03, /03L-0:on 820406,containment-plant Vent Radioactivity Monitors Became Inoperable When Air Supply to Valves 1VC8 & 1VC10 Tagged Out for Maint.Caused by Personnel Failure to Consider Loss of Air to Valves
05000324/LER-1982-075-03, /03L-0:on 820416,during Routine Surveillance, Drywell Floor Drain Flow Integrator 2-G16-FQ-K601 Indicated Continuous Sump Flow W/No Pumps Running.Caused by Operation of Integrator & Square Root Converter Out of Tolerance
05000334/LER-1982-011-01, /01T-0:on 820416,during Records Update Analysis Required by IE Bulletin 79-14,four Existing Supports on Three Parallel Branch Lines to High Head Safety Injection to RCS Cold Legs Were Identified as Deficient
05000267/LER-1982-010-03, /03L-0:on 820407 & 11,pure Helium Leakage in Steam Generator Interspace Found in Excess of Limits.Caused by Faulty Seal.Sys Modified
05000316/LER-1982-030-03, /03L-0:on 820401,both Steam Generator 1 Stop Valve Dump Valves Were Isolated at Same Time.Caused by Incorrect Orientation of Selector Valve MMO-210 During Initial installation.MMO-210 Will Be Reinstalled
05000272/LER-1982-026-03, /03L-0:on 820409 & 13,boric Acid Storage Tanks 11 & 12 & Boron Injection Tank Boron Concentrations Decreased Below Tech Spec Limit.Caused by Leakage of Charging Water Past Damaged Seat on 1SJ4
05000333/LER-1982-015-03, /03L-0:on 820327,during Normal Operation,Personnel Noted Sudden Increase in Indicated Containment Oxygen Concentration on Oxygen Analyzer A.Caused by Leakage on Inlet Side of Sample Sys for Analyzer
05000272/LER-1982-022-03, /03L-0:on 820405,svc Water Flow 14 Containment Fan Coil Unit Was Less than 700 Gpm Required.Caused by Decrease in Output Flow Control Valve 14SW57 High Speed Air Supply. Regulator Blown Down & Setpoint Readjusted
05000267/LER-1982-009-03, /03L-0:on 820306,during Valve Lineup for Authorized Gas Waste Release,Some Gas Released Through Vacuum Tank.Caused by Valve Left Open During Preparations. Unsampled Release Terminated & Valve Lineup Corrected
05000295/LER-1982-012-03, /03L-0:on 820305,during Refueling calibr,1D Steam Generator Level Transmitter 1LT-538 Found Out of Tolerance High by Max of 2.8%.Caused by Zero Shift on Transmitter 1LT-538(F/P 13D 2495)
05000267/LER-1982-006-03, /03L-0:on 820218,primary Coolant Moisture Exceeded Tech Specs.Caused by Contamination W/Moisture During Maint Outage.Reactor Shutdown & Coolant Purification Trains Utilized to Reduce Impurity Levels
05000315/LER-1982-011-03, /03L-0:on 820223,during Surveillance Per Tech Spec 4.8.2.5.2B,three Cells of N Train Battery Found to Have Electrolyte Gravity Less than 1.200 Min Limit.Caused by Low Readings & Loss of Acid.Acid Added & Battery Tested
05000295/LER-1982-011-01, /01T-0:on 820317,RHR Suction Pressure Transmitter 1PT-403 Failed High & Suction Valve 1MOV-RH8702 Started to Close.Caused by Piece of Sheet Metal Accidentally Dropped on Inverter 111 Output Breaker.Breaker Reclosed
05000304/LER-1981-038-03, /03L-0:on 811031,during Refueling Calibr,Loop 2A Steam Flow Channel 2F-512 Found 2.2% Low Out of Allowable Channel Tolerance.Caused by Combination of Xmtr Drift & Square Root Extractor Drift.Devices Recalibr
05000220/LER-1982-005-03, /03L-0:on 820208,115 Kv Line Taken Out of Svc for Maint,Placing Plant in Limited Condition of Operation.Maint on Line Required Due to Open Loop.Line Repaired & Returned to Svc
05000304/LER-1981-019-03, /03L-0:on 810825,during Normal Operation,Steam Generator Level X Meter 2LT-537 Found to Be High.Caused by Zero Shift.Transmitter Calibr & Returned to Svc
05000293/LER-1982-002-03, /03L-0:on 820118,sensing Line to Pressure Switch Found Frozen.Line Froze Again on 820119.On 820123,fire Pump Found Out of Calibr.Caused by Subzero Weather Which Reduced Effectiveness of Heating Sys.Priority Maint Requests Is
05000334/LER-1981-047-01, /01T-0:on 810606,emergency Cooling Water Supply Valve to High Head Safety Injection Pumps Was Discovered Unlocked & Closed.Cause Not Stated.Valve Opened.New Chain & Lock Installed.Investigation Underway
05000304/LER-1981-029-03, /03L-1:on 811115,2C Steam Generator Pressure Channel 2P-524 Failed High.Caused by Loose Ferrite Disc in Transmitter.Disc Secured,Transmitter Recalibr & Pressure Channel Returned to Svc
05000267/LER-1982-005-03, /03L-0:on 820215,loop 2 Steam Generator Penetration Rupture Disk 1 Leak Alarm Pressure Switch Found Isolated.Caused by Closed Pressure Switch Isolation Valve.Valve Opened
05000295/LER-1982-007-03, /03L-0:on 820216 & 17,1D Steam Generator Pressure Channel 1P-535 Failed Sporadically While in Hot Shutdown. Cause Not Stated.Several Transmitter Components Replaced. Transmitters in Critical Applications to Be Evaluated
05000293/LER-1982-004-01, /01T-0:on 820222,during Refuel/Mod Outage, Determined That Test Points on 20-inch Vent & Purge Butterfy Valve Flanges Were Not Type B Tested.Caused by Procedural Inadequacy.Procedures Revised
05000295/LER-1982-010-03, /03L-0:on 820302,containment Purge Exhaust (CPE) Isolation Valve 1RV-0003 Failed to Fully Close on Receipt of Automatic Closing Signal Generated from de-energization of CPE Radiation Monitors.Caused by Tygon Tubing Being Stu
05000309/LER-1982-006-03, /03L-0:on 820217,while Disassembling Spent Fuel Pit Cooling Pump Discharge Valve,Two 5/8-inch Studs Were Broken.Caused by Corrosion.All Type 416 Bolting in Valves Containing Borated Water Will Be Replaced
05000318/LER-1982-005-01, /01T-0:on 820223,discovered Jet Impingement Barrier in Main Steam Penetration Room Not Completely Installed.Caused by Personnel Error.Maint Procedure to Be Changed
05000295/LER-1982-004-03, /03L-0:on 820203,during Visual Insp,Snubber BDRS-1761 on Steam Generator Blowdown Piping Found in Airbound Condition Which Substantiated Inoperability.Caused by Poor Seal Condition.Snubber Tested & Reinstalled
05000315/LER-1982-009-03, /03L-0:on 820128,leak Discovered in Essential Svc Water Pipe Downstream of Outlet Valve from East Heat Exchanger.Caused by Cavitation Due to Throttling of Butterfly Valve.Mod Initiated
05000249/LER-1982-006-03, /03L-0:on 820122,quarterly Storage Battery Surveillances Not Performed for Third Quarter 1981. Caused by Miscoordination Between Implementing New Battery Check Procedure & Revising Computer Program
05000267/LER-1982-004-01, /01T-0:on 820202,inadvertent Radioactive Liquid Waste Release Occurred from Receiver a During Plant Shutdown for Design Mods to Circulator Auxiliary Sys.Caused by Improper Valve Lineup.Event Reviewed W/Operators
05000320/LER-1982-003-03, /03L-0:on 820111,during Weekly Scheduled Preventive Maint,Pump NR-P-1B Failed to Start.Caused by Loose Fuse Clip in Control Power Switchgear.Clip Repaired
05000325/LER-1982-004-03, /03L-0:on 820111,1-CAC-AR-1259 post-accident Monitoring Control Room Recorder/Indicator Exhibited Unvarying Indication of Drywell Oxygen Concentration.Caused by Broken Drive Cord Due to Normal Wear.Cord Replaced
05000320/LER-1981-038-01, /01L-0:on 811228,wind Direction & Wind Speed Monitoring Instruments on Meteorological Tower Became Inoperable Due to Ice Formation.Instruments Deiced Naturally.Util Awaiting Instrument Jacket Heaters Delivery
05000272/LER-1982-001-03, Pressurizer Overprotection Sys Valve 1PR1 Was Isolated Due to Leakage. on 820107,while Draining Rcs,Valve 1RP2 Would Not Open. Caused by Generic Problem.Reactor Vessel Head Removed
05000311/LER-1981-091-03, /03X-1:on 810817,unit Attained 85% Rated Thermal Power.Turbine Overspeed Protection Surveillance Required within 24-hr of Attaining 85% Power Was Overlooked.Personnel Counseled & Reminded of 24-hr Requirements
05000348/LER-1981-075-03, /03L-0:on 811222,fuel Storage Pool Area Radiation Monitor R-5 Declared Inoperable.Caused by Loose Electrical Connection on Breaker at 120-volt Control Power Panel Supplying Monitor.Connection Tightened.Monitor re-energized
05000293/LER-1981-065-03, /03L-0:on 811230,during Investigation of Failure of MSIV AO-203-2A,discovered Two hold-down Bolts on Poppet W/O Lock Plates.Caused by Failure to Follow Procedures During Previous Valve Overhaul
05000295/LER-1982-001-03, /03L-0:on 820112,discharge Damper on Oc Fan Found Failed Open W/Fan Off,Leaving Aircraft Fire Protection Sys for Auxiliary Bldg Air Supply Intake Inoperable.Caused by Frozen Bore in Air Operated Relay Valve
05000271/LER-1981-037-03, /03L-0:on 811227,while Attempting to Start RHRSW Pump P-8-1A,breaker Tripped Contrary to Tech Specs.Caused by Worn Bushings on Operating Mechanism.Circuit Breaker Replaced.Breaker Mfg by Ge,Model Am 4.16 250-8HB
05000311/LER-1981-131-03, /03L-0:on 811228,low Reading Noticed on 24 Reactor Coolant Loop Flow Channel 2.Channel Declared Inoperable. Caused by Failure of Flow Transmitter.Flow Transmitter Replaced & Calibr Satisfactorily
05000311/LER-1981-127-03, /03L-0:on 811215,operator Received Diesel Generator 2A Urgent Trouble Alarm.Caused by Failure of Prelubrication Oil Heater.Diesel Run Periodically to Maintain Oil Temp Above 110 F Until New Heater Is Installed
05000237/LER-1981-051, Has Been Cancelled
05000237/LER-1981-077-03, /03L-0:on 811216,ATWS Div 2 B & D Pressure Switches Found to Be Valved Out of Svc.Caused by Instrument Mechanic Valving Error.Switches Valved Back Into Svc & Individual Cautioned
05000304/LER-1981-033-03, /03L-0:on 811211,auxiliary Feedwater Pumps Failed to Automatically Start on Steam Generator Lo Lo Level Signal Following Reactor Trip.Caused by Pump Trip Due to Falsely Sensed Suction Pressure Following Pump Start
05000265/LER-1981-017-03, /03L-1:on 810907,relief Valve 2-203-3E in auto- Depressurization Sys Failed to Open.Caused by Grooves Worn in Disc Guide Sleeve by Rings of Main Valve Disc as Result of High Vibration
05000237/LER-1981-072-03, /03L-0:on 811203,standby Gas Treatment Sys Train B Tripped Following Group II & III Isolation Signal & Declared Inoperable.Caused by Plugged Orifice on Air Flow Controller, Stopping Air Flow & Falsely Indicating Fan Flow
05000366/LER-1981-123-03, /03L-0:on 811208,standby Gas Treatment Filter Train 2T46-C001B Tripped & Would Not Restart While Venting Primary Containment.Caused by Heater Control Relays Chattering.Relay Replaced
05000254/LER-1981-023-03, /03L-0:on 811126,small Steam Leak Found on Instrument Isolation Valve to Reactor Core Isolation Cooling Drain Pot Level Switch.Caused by Improperly Installed Isolation Valve.Weld Repaired & Sys Returned to Operability
05000304/LER-1981-030-03, /03L-0:on 811126,motor Driven Auxiliary Feedwater Pumps 2B & 2C Failed to Start.Caused by Low Suction Pressure Trips Being Set Too High Due to Calibr Error on Pressure Gauges.Gauges Reset
05000249/LER-1981-037-03, /03L-0:on 811119,while Performing Diesel Generator Operability Surveillance,Diesel Generator Exhibited High Coolant Water Temp.Caused by Defective Discharge Check Valve on Diesel Generator Cooling Water Pump
05000325/LER-1981-086-03, /03L-0:on 811125,during Routine Surveillance Discovered Primary Containment Atmospheric Monitor Oxygen Analyzer 1-CAC-AT-1259-2,Model F3M3 Tripped.Caused by Condensation.Analyzer Sample Lines Blown Down
05000295/LER-1981-048-03, /03L-0:on 811111,containment Particulate & Gas Rad Monitors (1RE-0011 & 12) Failed Due to Tripped Blower. Caused by Mechanical Failure of Conde P/N 6SFCWSB Blower.New Blower Will Be Installed
05000286/LER-1981-009-03, /03L-0:on 811110,battery Charger 31 Tripped.Cause Not specified.Delta-P Air Flow Sensing Switch Replaced
05000271/LER-1981-027-03, MSIV-80C Failed to Close on Receipt of Group 1 Isolation Signal During Reactor Scram. Caused by Actuator Failure.Actuator Completely Overhauled & Guide Rods,Spring Plate & Bushings Replaced
05000334/LER-1981-098-03, /03L-0:on 811107,w/reactor at 92%,technicians Performing 1B H2 Analyzer Maint Surveillance Procedure Reported Smoke Originating from H2 Analyzer Cabinet.Caused by Electrical Short within Wiring Harness.Short Repaired
05000254/LER-1981-022-03, /03L-0:on 811107,while Performing Routine Maint of 1/2 Diesel Generator,Babbitt Found in Oil Pan Due to Warped Bearing Cap 11.Caused by Pinhole Leak in Crossover Fuel Line Which Possibly Diluted Lube Oil to Bearing Cap
05000316/LER-1981-062-03, /03L-0:on 811029,while Performing Surveillance Test During Reactor Startup,Valve IMO-910,RWST to Charging Pump Suction,Would Not Open from Control Room.Cause of Hard Seating Undetermined.Torque & Switch Settings Verified
05000317/LER-1981-074-01, Determined That Component Cooling Isolation Valve to Containment CC-3832-CV Would Fail in Unconservative Position on Loss of Instrument Air. Administrative Controls Revised
05000293/LER-1981-061-01, /01T-0:on 811113,deep Gouges in Skin of Torus Internal Surface Found at Bottom of Bay 11 After Sandblasting.Apparently Caused by Carbon Arc Gauging.Repair Program Being Prepared
05000334/LER-1981-094-01, /01T-0:on 811116,overchlorination of Main Unit Condenser Occurred,Causing Discharge Limits to Be Exceeded. Caused by Personnel Error.Chlorination Monitoring Procedures Will Be Revised to Prevent Recurrence
05000293/LER-1981-062-01, /01T-0:on 811116,Wyle Labs Informed Util That Two Target Rock 2 Stage Safety/Relief Valves Had Not Passed Initial Setpoint Tests & Required High Pressure to Actuate. Cause Undetermined.Erosion of Pilot Discs Being Evaluated
05000220/LER-1981-008-01, /01X-1:on 810316,ultrasonic Testing Revealed Indication on Southeast Reactor Feedwater Nozzle Inside Bore.Caused by Inadequate Investigation.Dye Penetrant & Surface Exam Revealed Indication Nonreportable
05000237/LER-1981-065-01, /01T-0:on 811103,during Quarterly Surveillance, MSIVs 2-203-1A,1B & 1D Had Closure Times Less than Tech Specs.Caused by Misadjusted Timing Mechanism Due to Damper Seal Misalignment.Msiv 1B Due to Normal Operation
05000366/LER-1981-100-03, /03L-0:on 811016,diesel Generator 2c Failed to Reach Rated Speed & Voltage in Less That 12-s.Caused by Dirt in Field Flashing Relay.Relay Cleaned & Generator Successfully Tested
05000245/LER-1980-017, Has Been Cancelled
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
05000267/LER-1981-069-03, /03L-0:on 811104-09, Plant Operated in Degraded Mode.Caused by Moisture in Pcrv W/Reactor Power Less than 2% Resulting in Increased Offgassing When Plant Taken to High Power Levels for Core Temp Fluctuation Testing
05000267/LER-1981-067-03, /03L-0:on 811029,loop 2 Steam Generator Penetration Interspace Pressurization Isolation Valve Found Closed.Cause Unknown.Valve Reopened
05000247/LER-1981-024-03, /03L-0:on 811014,snubber 70-SR-13 on Pressurizer Relief Line & Bergen Patterson Hydraulic Snubber Hssa 3 Shaft Found Broken.Caused by Transverse Impact Load on Snubber Piston Rod.Snubber Replaced & Rod Analyzed
05000249/LER-1981-034-03, /03L-0:on 811026,source Range Monitor Channels 21 & 22 Found to Trip at Level Exceeding Tech Spec Limit.Caused by Drift of High Alarm Setpoint Potentiometer.Setpoints Adjusted
05000295/LER-1981-046-03, /03L-0:on 811023,U1 Offgas Particle & Gas Radiation Monitors Not Pulling Representative Sample & Release Path Not Being Continuously Monitored.Caused by Air in-leakage Due to Worn O-rings on Detector Housing Assembly
05000267/LER-1981-065-03, /03L-0:on 811017,hot Reheat Header Activity Monitors Temporarily Out of Svc for Completion of Radiography.Caused by Exccessive Leakage in Feedwater Heater 5.Radiography Required to Verify Welds
05000206/LER-1981-028-01, /01T-0:on 811030,during Safety Injection Sys Testing,Safeguards Load Sequencer 2 Failed Due to Internal Lockup Condition in Logic Card.Caused by Design Weakness in Card.Procedure Changes Implemented
05000293/LER-1981-057-03, /03L-0:on 811009 & 10,during Refueling,Limitorque Motor Operators on MOV 1001-32 & MOV 1001-36A Found to Have Loose & Broken CAP Screws Anchoring Motors to Valves. Probably Caused by Vibration Loosening hold-down Bolts
05000271/LER-1981-029-03, /03L-0:on 811018,during Two Rod Interlock Test, Rod Block Associated W/One Control Rod Withdrawal Permit Circuit Found Inoperable.Caused by False all-rods-in Signal to Reactor Manual Control Sys.Probe Replaced
05000324/LER-1981-114-03, /03L-0:on 811018,during Surveillance,Primary Containment Atmospheric Oxygen Analyzer 2-CAC-AT-1259-2 Showed Torus Oxygen Concentration 1% Higher than Indicated by Others.Caused Moisture Buildup Decreasing Flow
05000324/LER-1981-115-03, /03L-0:on 811019,during Investigation of Inoperability of RHRSW Subsys,Hydraulic Snubber 2-SW-175, SS166 Found Inoperable.Caused by Separation of Snubber Piston from Shaft Due to Piping Vibration
05000306/LER-1981-025-01, /01T-0:on 811029,during Test,Containment Purge Supply Penetration Leaked in Excess of Test Equipment Capacity.Probably Caused by Deformed Seating Matl,Small Dirt Accumulations on Valve Seats or Bolt Movement
05000282/LER-1981-024-03, /03L-0:on 811014,status Light Found Off & Breaker for Boric Acid Heat Tracing Switchrack Tripped.Caused by Personnel Failure to Respond to Trouble Alarm.Tripped Breaker Replaced
05000302/LER-1981-065-03, /03L-0:on 811008,during Performance of Remote Shutdown Instrumentation Calibr,Transmitters SP-1A-LT2 & SP-1B-LT2 Found Out of Tolerance.Caused by Instrument Drift. Instruments Recalibr
05000321/LER-1980-125, Has Been Cancelled
05000267/LER-1981-058-03, /03L-0:on 810911,station Battery Taken Out of Svc for Overcharging While Diesel Generator Was Under Repair. Caused by Operator Error.Battery Taken Off Overcharge & Returned to Svc
05000267/LER-1981-054-03, /03L-0:on 810820,emergency Feedwater to Loop 1 Helium Circulator Water Turbine Drive Was Isolated.Caused by Repair Necessary to Stop Leakage Between Seat Ring & Valve Body of Pressure Control Valve.Gasket Resurfaced
05000296/LER-1981-047-03, /03L-0:on 810907,during Normal Operation,Rhr Sys II Drywell Spray Isolation Valve 3-FCV-74-75 Failed to Operate Remotely.Caused by Broken Lug on Worm Shaft Clutch Gear on SMB-2 Limitorque Valve.Clutch Gear Replaced
05000260/LER-1981-044-03, /03L-0:on 810913,during Normal operation,hydrogen- Dioxide Analyzer B Sample Return Pump Discovered Inoperable. Caused by Failure of Pump Motor.Motor Repaired & Reinstalled
05000321/LER-1981-103-03, /03L-0:on 810914,during steady-state Operation, Recombiner Bldg Vent Radiation Monitor Failed Monthly Functional Test & Declared Inoperable.Caused by Component Failure.Defective Fuse Replaced
05000220/LER-1981-045-03, /03L-0:on 810916,temporary Change to Operating Procedures N1-ST-V4 Not Reviewed within 7-day Limitation. Caused by Mail Mixup.Processing Methods Revised
05000295/LER-1981-042-03, /03L-0:on 810908,during Normal Operation,Quarterly Surveillance on post-accident Sampling Sys Missed on Units 1 & 2.Caused by Radiation Protection Foreman Neglecting to Mark Scheduled Surveillance Date
05000265/LER-1981-018-03, /03L-0:on 810908,09,14,15,17,22,23 & 24 While Performing Main Steamline Local Leak Rate Tests,Ten Occurrences of Excessive Leakage Were Measured W/Respect to Primary Containment Isolation Valves
05000259/LER-1981-050-03, /03L-0:on 810903,during Operation,Interlocks for Doors 235 & 221 Failed Causing Breach of Secondary Containment.Caused by Personnel Actions Deactivating Emergency Bypass Pushbuttons
05000315/LER-1981-040-03, /03L-0:on 810901,during Operability Test of West RHR Pump IMO-322,RHR Pump Recirculation Valve Would Not Close Electrically.Caused by Motor Being Cut Out by Torque Switch Due to Packing Drag.Torque Switch Setting Increased
05000304/LER-1981-021-03, /03L-0:on 810903,during Test of Diesel Generator Cardox Sys,Diesel Room 2B Supply Fan Damper Failed in Open Position.Caused by Instrument Air Valve Valving Out
05000295/LER-1981-040-03, /03L-0:on 810830 & 0905,loop B Overtemp Delta T Indicator Found Reading Higher than Other Indicators.Caused by Deviation from Normal Gain Characteristics of Function Generator,Hagen Model 127-113.Generator Replaced
05000296/LER-1981-044-03, /03L-0:on 810830,during Performance of SI 4.1.A-8, Scram Discharge Vol 50-gallon Scram Switch 3-LS-85-45B Failed to Operate.Caused by Inoperable Switch.Switch Float Chamber Backflushed
05000293/LER-1981-048-03, /03L-0:on 810830,torus Temp Tech Spec Limit of 80 F Was Exceeded by One Degree F.Caused by One RBCCW Heat Exchanger Being Out of Svc & Entire RBCCW Heat Load Carried by Inservice Heat Exchanger.Operators Counseled
05000315/LER-1981-038-03, /03L-0:on 810820,during Routine Insp of 1AB Emergency Diesel,Taper Pin Fuel Rack Assembly Was Loose & Upon Removal Discovered to Be Broken.Cause Unknown.Insp of Linkage Pins Has Been Added to 18-month Insp
05000295/LER-1981-036-03, /03L-0:on 810106,during Surveillance Testing on Diesel 1A,abnormal Amount of Lube Oil Was Seen Leaking from Right Cylinder Head Cover 6.Caused by Broken Rocker Arm Due to Binding Between Arm & Rocker Stand.Diesel Repaired
05000271/LER-1981-019-03, /03L-0:on 810306,during Surveillance Testing of Standby Gas Treatment Charcoal Cells,Interfering Leak Found on Chromatogram.Cause Not Stated.Charcoal Replaced & Tested Satisfactorily
05000220/LER-1981-035-03, /03L-0:on 810721,site Operations Review Committee Failed to Review Temporary Change within 7-day Limit.Caused by Mail Mixup.All Temporary Procedure Changes Will Be Hand Carried to Committee Secretary
05000245/LER-1981-011, Has Been Cancelled
05000220/LER-1981-033-01, /01T-0:on 810709,while Operating at Approx 290 Mwe,Shaft Driven Feedwater Pump Start Resulted in Reactor Water Conductivity & Chloride Excursion.Caused by Incomplete Flush of Feedwater Sys.Reactor Water Cleanup Sys Initiated
05000272/LER-1981-051-04, /04X-1:on 810501,dead Shortnosed Sturgeon Removed from 12A Circulating Water Intake Trash Bar.Fish Assumed to Be Dead Prior to Impingement
05000293/LER-1981-033-03, /03L-0:on 810621,unidentified Drywell Leak Rate Exceeded Tech Specs.Cause Unknown.Inboard Clean Up Valve Electrically Backseated & Repacked
05000311/LER-1981-045-99, /99X-0:on 810423,inadvertent Safety Injection Occurred During Unit Cooldown.Caused by Personnel Error in Decreasing Automatic Setpoint.Personnel Counseled on Requirements to Follow Procedures
05000220/LER-1981-027-03, /03L-0:on 810623,leak Rate Test on Reactor Feedwater Isolation Valves 31-03 & 31-04 Showed Unacceptable Leakage.Caused by Limitorque Operator Failing to Put Out Enough Torque to Make Valve Seat Properly.Setting Increased
05000315/LER-1981-013-03, Source Range Ni Channels Declared Inoperable.Caused by Defective Source Range Detector N-32 Possibly Due to Dried Moisture Connectors. Detector Replaced
05000220/LER-1981-026-03, /03L-0:on 810624,while Performing Surveillance Test Procedure of Torus/Drywell Vacuum Relief Valves, Switches Which Monitor Distance Between Clapper & Seat Found Out of Spec.Cause Not Stated.Switches Recalibr
05000348/LER-1982-062-03, /03L-0:on 821231,noble Gas Activity Monitor R15 Declared Inoperable.Caused by Blown Fuse.Fuse Replaced & Monitor Returned to Svc
05000295/LER-1982-050-03, /03L-0:on 821224,overtemp delta-T Setpoint Loop 1B Indicator Observed Out of Tolerance High W/Respect to Three Redundant Loops.Caused by Drifting Function Generator 1NM-441B.Generator Recalibr
05000324/LER-1982-142-03, /03L-0:on 821218,PCIV B32-F058B,located at RIP X-241B,found Closed.Caused by Const Personnel Accidently Bumping Valve &/Or Associated Instrument Piping.Valve Opened & Personnel Counseled
05000346/LER-1982-068-03, /03L-0:on 821220,core Imbalance Vs Core Power Limit Computer Alarm C963 Inoperable.Caused by Mistake in Alarm Subroutine.Alarm Statement Corrected So Limits & Value for Imbalance Scaled Same
05000220/LER-1982-017-03, /03L-0:on 821206,during Maint Outage,Leakage from Valves 68-06 & 68-09 Found Exceeding Tech Specs.Caused by Poor Seal Design.Mods Will Be Completed During Current Outage & Followed by Retest
05000361/LER-1982-161-03, /03L-0:on 821206,condensation Storage Tank T-120 Water Level Fell Below Tech Spec.Caused by Inadequate Makeup Water Control.Operators Reinstructed.Engineering Evaluation Underway
05000361/LER-1982-163-03, /03L-0:on 821208,during Mode 1, Auxiliary Feedwater Pump 2P-140 Tripped on Overspeed.Caused by Failure of Resistor in Pump Speed Sensor Circuitry. Resistor Replaced
05000361/LER-1982-162-03, /03L-0:on 821207,w/plant in Mode 1,low Pressure Tubine Stop Valve 2UV-2200V on Low Pressure Turbine 3 Failed to Fully Close.Caused by Excessive Galling Between Disc Stub Shaft & Casing Bore.Stub Shaft Cleaned
05000366/LER-1982-143-03, /03L-0:on 821215,personnel Found Fire Protection Isolation Valves - Position & Lubrication Checks Procedure Performed 2 Days Late.Caused by Personnel Error.Personnel Admonished as to Importance of Surveillance
05000295/LER-1982-047-03, /03L-0:on 821205,RCS Loop C Indication Changed Suddenly,Delta Temp Pegged Low & Temp Average Pegged High. Caused by RTD Mechanism Failure.Spare RTD Placed in Svc.Part Will Be Replaced During Shutdown
05000366/LER-1982-131-03, /03L-0:on 821215,after Returning to Full Power, Inoperable Traveling in-core Probe Prevented Updating LPRM Calibr Data for Process Computer.Caused by Failed Electrical Connector.Connector Repaired
05000325/LER-1982-121-03, /03L-0:on 821130,RTGB Control switch,1-VA-CS-2581 for Standby Gas Treatment Sys 1B Was in Standby,Not Preferred Position.Caused by Failed Spring Return Function. Switch Repaired,Cleaned & Restored to Svc
05000346/LER-1982-054-03, /03L-0:on 821021,Door 107 to Radiation Equipment Found Partially Open & Blocked by Hose When Personnel Attempted to Perform Routine Flush on RE-1878.Caused by Personnel Error.Personnel Counseled
05000334/LER-1982-050-04, /04T-0:on 821103,during Third Quarter 1982 Composite of Weekly Effluent Samples,Tritium Activity Exceeded Ets.Caused by Normal Operation.Discharge Reported. ETS Will Be Amended to Increase Limit Per 10CFR20
05000373/LER-1982-168-03, /03L-0:on 821201,steam Leak Discovered on Pressure Sensing Line for RCIC Instruments DPIS 1E31-N0007B & Ps 1E31-N022B&D.Caused by Failure of Compression Fitting on Instrumentation Steam Pressure Line.Leak Repaired
05000373/LER-1982-135-03, /03L-0:on 821021,div 1 ID18-N009B Reactor Bldg Ventilation Process Radiation Monitor Drifted High.Caused by Failed Geiger-Muller Tube Mfg by Lnd.Tube Replaced
05000265/LER-1982-018-03, /03L-0:on 821006,emergency Diesel Generator Tripped on High Temp.Caused by Fouling of Diesel Generator Cooling Water Sys Hx.Hx Replaced.Diesel Generator Tested & Found Operable
05000254/LER-1982-033-03, /03L-0:on 821005,1A2 Battery Cell 12 Dropped Below Tech Spec Limits,Resulting in Battery a Failure to Pass Discharge Test.Caused by Battery Age & Repetitive Discharge Testing.New 24/48-volt Dc Battery Will Be Installed
05000213/LER-1982-007-03, /03L-0:on 820927,operator Received Rod Drive Slave Cycler Failure/Rod Stop Alarm,Rendering All Bank B Subgroups Inoperable.Caused by Master Cycler Relay Hanging Up Due to Poor Relay Contact.Mercury Wetted Contacts Rewet
05000293/LER-1982-040-03, /03L-0:on 820920,found Reactor Protection Sys Initiation Function of Turbine Stop Valve Completed 1 Day Late.Caused by Decision to Defer Test Due to MSIV D Line Isolation.Tracking Sys Implemented to Prevent Recurrences
05000346/LER-1982-049-03, /03L-0:on 820920 & 22,Channels 2 & 3 on Containment post-accident Radiation Monitor Re 4597BA Were Reading High.Caused by Problem in Microprocessor Software. New Set of Software Installed & Faulty Actuator Replaced
05000334/LER-1982-037-03, /03L-0:on 820921,steam Generator 1A Level Protection Channel III Signal Comparator LC-FW476A Declared Inoperable Due to Faulty Actuation & Trip Setpoint Drift Found During Surveillance Testing.Hagan Comparator Replaced
05000334/LER-1982-035-03, /03L-0:on 820917,delta Flux Exceeded Required Target Band.Caused by Low Heater Drain Tank Level,Leading to Load Reduction.Control Rods Borated Out to Return Delta Flux to within Target Band
05000272/LER-1982-057-03, /03L-0:on 820803,during Routine Operation, Circulator 13A Tripped Resulting in Rapid Load Reduction. Caused by Grass & Debris Clogging Travelling Screen.Screen Cleaned & Circulator Returned to Svc
05000272/LER-1982-061-03, /03L-0:on 820811,svc Water Flow Indication for Containment Fan Coil Unit 13 Erratic.Caused by Silt Plugging High Side Sensing Line of Outlet Flow Transmitter.Sensing Lines Blown Down.Transmitter Returned to Svc
05000237/LER-1978-061-03, /03L-0 on 781108:AO-2-1601-24 Failed to Close Due to Solenoid Valve Stuck Open W/Dirt in Valve Internals. Solenoid Valve Replaced,Tested & Returned to Svc
05000346/LER-1978-112-03, /03L-0:on 781109,ST 5011.01, Boron Injection Flowpath Test Performed 7.5-h Later than Allowed.Caused by Sys Design Requiring Frequent Additions of Water.Facility Change Request Prepared
05000317/LER-1978-043-04, /04T-0 on 780912:approximately 6200 Menidia (Atlantic Silversides) Were Collected Between 0900 & 1000 Hours from U-1 Travelling Screens.Studies After 1000 Hours Did Not Reveal Any Unusual Numbers of Impinged Fish
05000412/LER-1990-021, :on 901113,ESF Actuation & Feedwater Isolation Occurred During MSIV Stroke Testing.Caused by Operator Error.Feedwater Isolation Signal Reset & Isolation Valves Reopened
05000321/LER-1983-070-03, /03L-0:on 830810,during Performance of RHR Pump Operability Procedure,Neither Flow Indicator 1E11-R603A Nor Flow Recorder IE11-R608 Indicated Flow for RHR Loop A.Caused by Failed Flow Transmitter
05000366/LER-1983-064-03, /03L-0:on 830811,during post-maint Review of DCR 83-76 Determined Torus Vent Valves Instrument Air Piping Returned to Svc W/O Performance of HNP-6907.Caused by Personnel Oversight
05000321/LER-1983-079-03, /03L-0:on 830809,main Steam Line & Reactor Water Sample Valve Relay 1A71-K7A Determined Operating in Degraded Mode.Caused by Component Failure.Coil & Contacts Replaced
05000366/LER-1983-072-03, /03L-0:on 830802,personnel Observed Amber (Open) Indicating Light for Safety Relief Valve Did Not Light W/Switch in Open Position.Cause Unknown.Jumper Wire Placed on Terminal
05000237/LER-1983-055-01, /01T-0:on 830719,one 1/8 by 1/16-inch Hole Found on Bellows Seal on Torus to Drywell Vacuum Breaker Line Containing Breakers 2-1601-32A & B.Cavity Filled to Original Thickness & Surface Buffed
05000295/LER-1983-020-03, /03L-0:on 830713,unidentified RCS Leak Rate of Approx 1.6 Gpm Found.Caused by Packing Leakage of 0.8 Gpm of Two Boron Injection Tank Inlet Valves.Work Requests Issued & Leakage Reduced to Less than 1 Gpm
05000321/LER-1983-058-03, /03L-0:on 830629,only One Closed Indicating Light Activated for Torus a to Drywell Vacuum Breaker 1T48-F323A. Cause Undetermined.Events to Be Investigated & Repairs Made During Next Cold Shutdown
05000321/LER-1983-063-03, /03L-0:on 830626,torus Water Level Indicator B (1T48-R622B) Found Indicating Erroneously.Caused by Sensing Line Being Full of Air Instead of Water Due to Packing Leak. Packing Tightened
05000366/LER-1983-049-03, /03L-0:on 830701,during Performance of Procedure HNP-2-3882,surveillance Personnel Noted That Hydrogen & Oxygen Analyzer a Inoperable.Caused by Gas Flow Meter Not Controlling Reagent Gas & Stripped Gear Drive
05000346/LER-1983-028-03, /03L-0:on 830603 & 17,fuel Handling Area Radiation Monitors RE8446 & 7 Found Deenergized.Caused by Blown Radiation Monitoring Cabinet Fuse.Fuse Replaced
05000320/LER-1983-015-03, /03L-0:on 830527,one Halon Bottle Found W/Low Pressure & Low Weight During Surveillance of Air Intake Tunnel Halon Sys.Caused by Development of Leak in Bottle or Fittings.Bottle Replaced
05000320/LER-1983-014-03, Air Intake Tunnel Halon Sys Actuated,Causing Actuation of Deluge Sys & Trip of Auxiliary & Fuel Handling Bldgs Supply & Exhaust Fans.Caused by Short in Actuation Leads.Sys Repaired
05000247/LER-1983-017-03, /03L-0:on 830422,leak Observed in Isolation Valve Seal Water Sys.Caused by Damage to 3/8-inch Stainless Steel Weld Connection FW10016.Weld Repaired
05000318/LER-1983-025-03, /03L-0:on 830426,saltwater Inlet Valves to Circulating Water Pump Room Air Coolers SW5250 & SW5251 Discovered Open While Automatic Safety Injection Actuation Signal Disabled.Caused by Inadequate Procedure
05000346/LER-1983-024-03, /03L-0:on 830511,while Starting Up from 830510 Reactor Trip,Quadrant Power Tilt in Quadrant Yz Exceeded Tech Spec steady-state Limit.Caused by Inherent Design of B&W NSSS & Negative Moderator Temp Coefficient
05000416/LER-1983-046-03, /03L-0:on 830412,monthly Functional Surveillance for Div I Chlorine Detection Sys Not Performed by 830410. Caused by Personnel Error
05000348/LER-1983-015-03, /03L-0:on 830328,instrumentation Channel Associated W/Steam Generator 1C Flow Transmitter FT-497 Declared Inoperable Due to Erroneous High Indication.Caused by Obstruction of Low Pressure Sensing Line.Line Cleared
05000416/LER-1983-060-03, /03L-0:on 830329,during Cold Shutdown,Load Shedding & Div I LSS Sequencing Panel Failure Alarm Actuated.Caused by Failure of 15-volt Dc Power Supply Used to Power Solid State Electronics for Sys Logic
05000280/LER-1981-054-03, /03L-0:on 810923,during Cold Shutdown,Higher than Normal Activity Detected in Storm Drain Sys.Attributed to Leaks from Stripper Feed Steam Heater Caused by Four Tubes Leaking in Heat Exchanger Bundle & Receiver Pumps Failure
05000324/LER-1981-073-03, /03L-0:on 810920,24 & 1007,diesel Generator 4 Did Not Attain Rated Speed in Required Time When Started.Caused by Intermittent Electrical Connection on Diesel Right Starting Air Bank Dc Solenoid Valve.Connection Repaired
05000261/LER-1980-014, Updated LER 80-014/01T-1:on 800702,vendor Info Indicated That No Certification of Qualification Was Available for PVC Electric Cable Pigtails Used on Eight Penetrations.Cable Pigtails Meet Design Specs & Accident Requirements
05000321/LER-1981-095-03, /03L-0:on 810908,reactor Core Isolation Cooling Steam Line Delta P Switch Actuated at Level Outside Tech Specs Range.Caused by Setpoint Drift.Switch Recalibr.Rept Will Be Updated When Switch Is Replaced
05000261/LER-1981-020-03, /03L-0:on 810902,containment Spray Check Valve SI-890B & Associated Flow Path Declared Inoperable.Caused by Failure to Perform Post Maint Testing Prior to Startup Due to Oversight.Valve Tested.Procedures Will Be Revised
05000267/LER-1981-052-03, /03L-0:on 810812,standby Bearing Water Makeup Pump Removed from Svc.Caused by Need to Repair Bonnet Leak in Valve in Suction Line to Pump.Pump Returned to Svc After Repair Completed
05000295/LER-1981-031-03, /03X-1:on 810624,during Normal Operation,Fire Sump Radiation Monitor ORT-PR25 Spiked High for Several Minutes. Caused by Natural End of Life of Detector Tube.Tube Replaced
05000267/LER-1981-049-03, /03L-0:during 810802-07,increase Occurred in Offgassing from Core & Core Outlet Temps.Caused by Increased Primary Coolant Moisture & Oxidants from Refueling Shutdown
05000366/LER-1981-078-03, /03L-0:on 810820,reactor Core Isolation Cooling Flow Controller Demand Was at Less than 100% While in Either Auto or Manual.Caused by Faulty Resistor in Ramp Generator. Units Replaced
05000220/LER-1981-040-03, /03L-0:on 810818,chromated Water Found in Diesel Generator 102 Raw Water Due to Water Leaking Through Heat Exchangers.Cause Unknown.Raw Water Lines Drained & All Chromate Recovered
05000213/LER-1981-013-03, /03L-0:on 810803,EG2A Emergency Diesel Generator Could Not Be Phased on to Conduct Routine Surveillance Test. Caused by Lack of Governor Control.Motor Operated Potentiometer Replaced in Governor Control Circuit
05000334/LER-1981-070-03, /03L-0:on 810729,review of Containment Isolation Valve Stroke Time Surveillance Test Showed That Four Containment Purge & Exhaust Dampers Exceeded Required Stroke Time.Caused by Personnel Error
05000334/LER-1981-072-03, /03L-0:on 810731,surveillance Test Conducted on Inner Air Lock of Containment Failed Leakage Rate Tech Spec Requirement.No Cause Stated.Air Lock Seal Replaced & Test Successfully Completed
05000324/LER-1981-089-03, /03L-0:on 810817,primary Containment Atmospheric Oxygen Analyzer 2-CAC-AT-1263-2,Model F3M3 Found W/Drywell Oxygen Concentration High.Probably Caused by Instrument Drift.Analyzer Recalibr.Analyzers to Be Replaced
05000271/LER-1981-021-03, /03L-0:on 810730,containment Isolation Valve V20-94 Failed to Close During Surveillance Testing.Possibly Caused by Normal Wear W/Accumulation of Minor Amounts of Dirt.Insp of Air Solenoid Valve Was Inconclusive
05000324/LER-1981-078-03, /03L-0:on 810804,RHR SW Subystem Pump a Would Not Start Due to Pump Suction Header Low Pressure Lockout Signal from Header Pressure Switch.Caused by Loose Plug in Switch Diaphragm Housing,Allowing Diaphragm Fluid to Leak
05000293/LER-1981-044-03, /03L-0:on 810801,problems Encountered W/Start of Recirculation Pump Motor Generator Set P201A.Caused by Blown Capacitor,Preventing Scoop Tube Positioner from Entering Startup Position.High Speed Limiter Card Replaced
05000271/LER-1981-022-03, /03L-0:on 810801,MSIV-80D Failed to Close When Control Switch Was Placed in Closed Position.Caused by Foreign Particle Lodged in Spool Valve,Preventing Air from Operating Main Piston.Msiv Fully Stroked
05000237/LER-1981-049-01, /01T-0:on 810814,valves 2-203-1A & 2-203-1D Had Closure Time Limits of 2.1-s & 1.7-s,respectively.Caused by Misadjusted Timing Mechanisms on Valves.Valves Adjusted
05000304/LER-1981-017-03, /03L-0:on 810710,components in Step 11 of PT-10 Did Not Actuate Via SI Signal from Train a During Quarterly Safeguards Surveillance.Caused by Wrong Position of 120-volt Ac Power Supply Breaker Switch for Relays
05000315/LER-1981-025-03, /03L-0:on 810714,during Leak Rate Testing,Several Valves Found Leaking.Caused by Sand Deposits on Seating Surfaces & Erosion of Valve Seats.Valves Repaired
05000311/LER-1981-057-03, /03L-0:on 810708,auxiliary Feed Storage Tank Level Dropped Below Required Level.Caused by Lack of Demineralized Water Available for Makeup.Personnel Counseled & Tank Restored to Required Level
05000364/LER-1981-027-03, /03L-0:on 810714,during Test,A Train Penetration Room Filtration Sys Was Declared Inoperable When Associated Fan Damper Failed to Open.Caused by Faulty Solenoid Valve. Valve Replaced.Sys Returned to Svc
05000260/LER-1981-035-03, /03L-0:on 810708,while Performing Level Switch Testing,Scram Discharge Instrument Vol Tank Level Switch 2-LS-85-45F Failed to Operate.Caused by Inoperable Robertshaw Level Switch Model SL-305-EI-X.Switch Replaced
05000133/LER-1981-003-03, /03L-0:on 810629,during Nonroutine Insp of Liquid Waste Sys,Vent Monitor Alarm Setpoint Background Reading Found High.Caused by Personnel Error.Setpoint Restored & Personnel Reinstructed
05000295/LER-1981-032-03, /03L-0:on 810629,RCS Charging Pump 1A Balancing Drum Line Was Found Leaking from Circumferential Indication Upstream of Weld Connecting Line to Suction of Pump Casing. Caused by Vibration of Drum Piping.Piping Repaired
05000261/LER-1981-018-03, /03L-0:on 810701,Channel I (PI-474) of a Steam Generator Steam Line Pressure Indicated High Compared to Two Redundant Channels.Caused by Throttled Root Isolation Valve MSV-14.Valve Reopened
05000321/LER-1981-064-03, /03L-0:on 810701,HPCI Steam Line Pressure Switches 1E41-N001B & D Actuated at 101 & 106 Psig,Respectively. Caused by Switch Setpoint Drift.Switches Recalibr
05000261/LER-1981-016-03, /03L-0:on 810611,during Startup,Motor Driven Auxiliary Feedwater Pump a Tripped Due to Low Discharge Pressure While Feeding Steam Generators.Event Reoccurred on 810716.Caused by Backleakage Through Discharge Valve AFW-40
05000260/LER-1981-033-03, /03L-0:on 810702,reactor Low Pressure Permissive Switch for Recirculation Pump Discharge Valve Actuation Switch 1 Failed.Cause Unknown.Switch Freed & Exercised to Verify Operability.Considered Random Failure
05000324/LER-1981-051-03, /03L-0:on 810608,during Operability Testing,When Manual Start Was Initiated,Diesel Generator 4 Started & Then Stopped.Caused by Moisture in Run Control Solenoid Valve, Model X53-HM-2150.Moisture Removed
05000321/LER-1981-078-03, /03L-0:on 810712,torus Water Temp Found Above Allowable Temp Level.Caused by Testing of Reactor Core Isolation Cooling & HPCI Turbines.Temp Was Reduced to Allowable Level
05000296/LER-1981-032-03, /03L-0:on 810701,leak Discovered at Vent Nipple of RHR Pump Room Cooler 3A.Cause Unknown.Crack Was Silver Soldered
05000324/LER-1981-061-03, /03L-0:on 810629,during Test,Diesel Generator Failed to Develop Generator Field Voltage.Caused by Failed Electrical Coil in Field Shorting Device 17 Preventing Generator Field from Flashing When Diesel Started
05000324/LER-1981-056-01, /01T-0:on 810624,notification Received That 38 Pipe Supports Would Have Failed During Design Basis Seismic Event.Caused by Higher than Normal Slenderness Ratio. Identified Supports Upgraded
05000293/LER-1981-028-99, /99L-0:on 810617,facility Organization Was Revised to Eliminate Chief Operation Engineer Position & Create Watch Engineer Position.Caused by Need for Direct Communication of Operating Experience to Mgt
05000321/LER-1981-062-03, /03L-0:on 810630,during Normal Operations, Isolation Valve for drywell-to-torus Sys Differential Pressure Instruments Found Closed,Isolating Instruments. Caused by Personnel Error.Valve Position Corrected
05000261/LER-1981-017-03, /03L-0:on 810619,auxiliary Feedwater Pump a Tripped on Low Discharge Pressure.Caused by Improper Throttle Setting of Discharge Valve.Valve Repositioned
05000366/LER-1981-069-03, /03L-0:on 810630,average Power Range Monitor Surveillance Not Performed within Required Time Limit. Caused by Personnel Error.Surveillance Performed
05000334/LER-1981-062-03, /03L-0:on 810619,auxiliary Flow Path to Steam Generator 1A Was Isolated.Caused by Maint on Leaking Feed Flow Transmitter Instrument Line Penetration Into Auxiliary Feed Flow Header A.Piping Refabricated
05000366/LER-1981-067-03, /03L-0:on 810626,site Notified That Procedures Used for Checking Positions of Psw Valves Serving safety- Related Equipment Were Inadequate.Caused by Erroneous Determination That HNP2-3182 Confirms Valve Position
05000366/LER-1981-058-03, /03L-0:on 810622,during steady-state Operation at 2,194 Mw,Reactor Bldg to Torus Vacuum Breaker Isolation Valve 2T48-F310 Failed Open.Cause Attributed to Torus Differential Pressure Switch Setpoint Drift.Switch Recalibr
05000304/LER-1981-014-03, /03L-0:on 810619,svc Water Inlet Valve to RCFC, 2MOVSW0002,failed to Stroke Open on Train B Actuation Signal Per Tech Spec,During Quarterly Safeguard Surveillance.Cause Not Determined
05000295/LER-1981-004-03, Microswitch 2FIC-611A, Controlling Only Valve on RHR Recirculation Line B,Found to Be Defective.Caused by Faulty Procedure Used to Check Switch Calibr.Procedure Revised & Switches Tested
05000315/LER-1981-019-03, /03L-0:on 810608,section of Piping W/Hand Valve Found to Have Never Been Leak Tested.Review of Plant Documents Failed to Determine Time of Installation or Purpose.Request Issued to Remove Valve & Seal Weld Piping
05000321/LER-1981-059-03, /03L-0:on 810620,delta P Was Not Established within Required Time After Mode Switch Was Placed in Run Mode.Caused by Steam Supply to Vaporizer Not Being Available Due to Slow Inerting of Drywell to Less than 4% O
05000237/LER-1981-005-03, During Local Leak Rate Testing,Measured Leakage of Single Isolation Valve Exceeded Tech Specs.Caused by Normal Deterioration of Valve Seat. Valve Replaced
05000295/LER-1981-023-03, /03L-0:on 810422,discrepancies in PT-210 Were Not Reported.Fan Dampers Failed to Open on Fan Start,Fan Failed to Start & Relief Dampers Failed to Close on Fan Trip.Caused by Lack of Tech Spec Directions.Mods Under Investigat
05000311/LER-1981-035-01, /01T-0:on 810616,during Repair of Valve Bonnet Leak,Check Valves 21MS46 & 23MS46 Found to Be Internally Damaged.Cause of Damage Being Investigated.Check Valves Repaired
05000334/LER-1981-041-04, /04T-1:on 810513,tritium Level in Quarterly Composite of Weekly Grab Samples Collected from Oh River Was Found Higher than Tech Spec Requirements.Caused by Normal Plant Discharge.New Tech Spec Limits Submitted
05000311/LER-1981-030-03, /03L-0:on 810530,during Startup Operations, Auxiliary Feed Pump 21 Outboard Bearing Went Into High Temp Alarm & Was Removed from Svc.Caused by Failure of Outboard Bearing & Seal Assembly.Components Replaced
05000220/LER-1981-023-03, /03L-0:on 810603,while Performing Local Leak Rate Testing,During Refueling Outage,Torus Vacuum Breaker Valve 68-08 Failed to Meet Tech Spec Requirements.Caused by Worn Seating & Packing Matl.Rubber Goods Replaced
05000311/LER-1981-034-03, /03L-0:on 810603,during Refill of Boron Injection Tank,Samples Indicated Concentration Less That 20,000 Ppm. Caused by Boron Tank Not Completely Drained Prior to Refill.Tanks Borated to Between 20,000 & 22,500 Ppm
05000320/LER-1979-014-01, /01L-0:on 790328,during Normal Operation,Unit Experienced Loss of Feedwater.Intensive Study of Procedural Activities Carried Out by Nrc.Summary of Violations,Causes, Sequence of Events & Corrective Actions Encl
05000265/LER-1981-006-03, /03L-0:on 810312,differential Pressure Between Drywell & Suppression Chamber Was Lost.Caused by Isolation of Differential Pressure Sys Due to Short in Electrical Circuit Resulting in Blown Fuse.Fuse Replaced
05000295/LER-1981-022-03, /03L-0:on 810528,instrument Inverter 114 Failed Concurrent W/Performance of Instrument Functionals,Resulting in Reactor Trip.Caused by Shorted Primary Windings of Master Sola Output Transformer.Unit Returned to Manufacturer
05000324/LER-1981-050-03, /03L-0:on 810613,during Routine Surveillance, Primary Containment Atmosphere Monitor Oxygen Analyzer 2-CAC-ATH-1259-2 Was Showing Erratic Indications of Drywell & Suppression Pool Oxygen Concentrations.Caused by Bad Tube
05000206/LER-1981-007-01, /01T-0:on 810515,pump to Motor Coupling Failed During Qualification Testing of RHR Pump Motors.Caused by Corrosive Effects of Environ & Unnatural Stresses to Coupling Due to Test Setup.Couplings Will Be Replaced
05000266/LER-1981-005-03, /03L-0:on 810515,control Room Emergency Filtration Sys Fans,Common to Both Units,Found Operating Outside Design Flow Rates Per Tech Specs.Caused by Improperly Balanced Backdraft Damper at Fan Discharge.Dampers Readjusted
05000304/LER-1981-007-03, /03L-0:on 810508,valve Drifted Open While Unit Was in Hot Shutdown & After Taking 2D MSIV Oos.Caused by Both MSIV Drain Valve Not Opening After Closure & Hydraulic Leakage Pressurizing Piston Opening Side
05000267/LER-1981-029-03, /03L-0:on 810420,1D Emergency Diesel Engine of 1B Emergency Generator Set Failed Weekly 50% Load Test. Caused by Failed Injector 1.Injector & Precombustion Chamber Replaced & Generator Returned to Svc
05000334/LER-1981-044-03, /03L-0:on 810430,refueling Water Storage Tank Channel C Level Indicator Found Reading High.Caused by Level Transmitter.Transmitter Replaced.Corrective Action Incorrectly Reported to Have Taken Place 810416
05000298/LER-1981-006-03, /03L-0:on 810414,during Normal Surveillance Testing of Scram Discharge Header Cms,Three of Four Channels Installed Failed.Caused by Component Failure.Marginal Crystals Used in Transmitter Replaced by Manufacturer
05000333/LER-1981-040-03, /03L-0:on 810505,RHR Flow Indicator 10-FI-133A Was Found Out of Calibr.Probably Caused by Instrument Drift. Indicator Recalibr
05000324/LER-1981-048-01, /01T-0:on 810513,while Evaluating RIP Isolation Valve Failure,Eccs Actuation Instrument E41-LSH-NO15B Isolation Was Not Recognized.Caused by Personnel Emphasis on Returning Isolation Valve to Svc.Control Switch Replaced
05000366/LER-1981-041-03, /03L-0:on 810426,diesel Generator 1B Declared Inoperable.Caused by Spurious Trip from High Crankcase Pressure Switch W/Generator in Manual Start Mode.Generator Proven Operable & Returned to Svc
05000366/LER-1981-044-03, /03L-0:on 810504,HPCI Min Flow Valve Would Not Operate After Being Closed W/Control Switch During Operability Test.Caused by Pressure Switch HPCI Pump Discharge Failing W/Valve Closing.Bourdon Tube Replaced
05000259/LER-1981-014-03, /03L-0:on 810424,MSIVs 1-14,1-15,1-37,1-38,1-51 & 1-52 Exceeded Tech Specs Allowable Leak Rate During Testing.Caused by Slight Steam Erosion Due to Deterioration of Valve Seating Surfaces.Maint & Retest Performed
05000306/LER-1981-004-03, /03L-0:on 810406,during testing,turbine-driven Auxiliary Feedwater Pump 22 Failed to Come Up to Rated Speed.Caused by Low Governor Setting.Governor Adjusted to Proper Speed
05000213/LER-1981-002-03, /03L-0:on 810322,operator Noticed Mar Readings of HPSI Pump Closed Discharge Pressure Had Not Been Plotted. Caused by New Operators Not Knowledgeable About Test or Requirements & Procedure Not Spelled Out
05000324/LER-1981-018-03, /03L-0:on 810210,primary Containment Atmospheric Monitor Hydrogen analyzer,2-CAC-AT-1263-1,model 7C,showed Varying Indications.Cause Unknown.Indication Was Found Steady Upon Investigation
05000293/LER-1981-005-03, /03L-0:on 810202,unidentified Reactor Drywell Coolant Leakage Rates Measured Above Tech Spec Level.Cause Not Stated.Recirculation Pump Suction Valves a & B & Discharge Valves Backseated
05000293/LER-1981-007-03, /03L-0:on 810217,reactor Coolant Leak Detection Air Sampling Sys Declared Inoperable.Caused by Blown Fuses. Fuses Replaced.Pump Will Be Rebuilt
05000267/LER-1981-010-03, /03L-0:on 810120,five Sample Flow Circuits Found Out of Calibr.Caused by Change of Instrument Characteristics.Calibr Values Revised & Flow Transmitters Recalibr.Alarm Setpoint Functional Test Values Also Changed
05000324/LER-1980-100-03, /03L-0:on 801231,low Power Range Monitor 36-21C Found Providing Faulty Input Signal to Rod Block Monitor A. Cause Unknown.Monitor Bypassed.Supplemental Rept Will Be Issued
05000317/LER-1981-010-03, /03L-0:on 810123,nipple Broken on Valve CV-5178, Salt Water Emergency Return Isolation from ECCS Pump Room Coolers.Caused by Lead Brick Fall During Const of Lead Shield Wall.Valve Isolated & Nipple Replaced
05000267/LER-1981-007-03, /03T-0:on 810108,during Pcrv Cooling Water Sys Data Evaluation,Violation of Limiting Conditions of Operation Found Re Loop 2 Inlet & Outlet Average Temp Below Tech Spec Limit.Caused by Insufficient Heat Input
05000259/LER-1981-001-03, /03L-0:on 810105,core Spray Sparger to Reactor Pressure Vessel D/P Switch 1-PDIS-75-28 Found Set Above Tech Spec Limit.Caused by Barton Model 288 Setpoint Drift.Switch Replaced W/New Switch on 810115
05000293/LER-1980-095-03, /03L-0:on 801209,fire Brigade Not Summoned When Electrical Fire Occurred in Security Bldg Mechanical Room. Caused by Personnel Error.Personnel Instructed of Necessity to Follow Procedures for Summoning Brigade
05000266/LER-1981-001-01, /01T-0:on 810102,while Performing Monthly Ventilation Sys Test,Supply Breaker for Safeguards Motor Control Ctr 1B42 Tripped.Caused by Dust in Instantaneous Trip Valve on Breaker.Breaker Cleaned & Tested
05000267/LER-1980-056, Has Been Cancelled
05000324/LER-1980-105-03, /03L-0:on 801202,TIP Machine a Found W/O TIP Indication Which Prevented Closing of a TIP Ball Valve. Caused by Bent Tube Guide Chafing & Extending Probe Cable Until Breakage Occurred
05000334/LER-1980-087-03, /03L-0:on 801113,operator Attempted to Perform Operation Surveillance Test on Intermediate Range Nuclear Instrument While Reactor Was Critical.Caused by Operator Error & Possible Inadequate Situational Analysis Guidance
05000334/LER-1980-084-03, /03L-0:on 801107,boron Injection Tank Low Temp Annunciation Received.Caused by Ground in Inservice Heat Trace Circuit.Ground Eliminated
BSEP-81-0015, Ro:On 810103 During Normal Reactor Startup & Heatup W/ Reactor Pressure at 717 Psig,Safety Relief Valve B21-F013G Lifted,Causing Feed Pump to Trip.Low Level Reactor Scram Resulted.Pilot to F013G Replaced
05000293/LER-1981-016-03, /03L-0:on 810430,reactor Core Isolation Cooling Valve Mo 1301-17 Failed to Close on Demand Following Switch Actuation.Caused by Deteriorated Packing Jammed Between Valve Stem & Packing Gland.Packing Replaced
05000259/LER-1981-007-03, /03L-0:on 810210,during Fire Door Insp,Fire Door Damper (Door 472) Not Closed.Caused by Paint Buildup in Operating Mechanism.Damper Closed & Other Dampers Inspected. Procedure for Insp & Preventive Maint Will Be Written
05000334/LER-1981-009-03, /03L-0:on 810117,MOV-SI-864B Containment Isolation Valve Stroked Shut But Failed to Reopen During Surveillance Test.Caused by Valve Open Torque Cutout Switch Being Out of Adjustment.Switch Adjusted & Returned to Svc
05000348/LER-1980-077-03, /03L-0:on 801128,loop Suction Valve for a Train RHR Closed,Resulting in a Train RHR Being Inoperable.Caused by Dirty Contacts on Circuitry Card for Pressure Transmitter.Card Cleaned
05000334/LER-1980-105-03, /03L-0:on 801205,thermocouple Readings Indicated Temps Below Tech Spec Level Around Boron Injection Tank Outlet Isolation Valves.Caused by Thermocouples Not in Full Contact W/Pipes.Heat Tracing Sys Study Is Being Conducted
05000267/LER-1980-071-03, /03L-0:on 801106,malfunction of Helium Circulator 1B Speed Modifier Caused Loss of Plant Protective Sys Function of High Speed Trips to One of Three Channels.Caused by Resistance Change in Speed Element Cable Assembly
05000309/LER-1980-017-01, /01T-1:on 800822,during Steady State power,25,000 Gallon Blended Makeup Made to Rwst.Boron Sample Indicated Concentration of 1,704 ppm;16 Ppm Below Tech Spec Required Value of 1,720 Ppm.Caused by Insufficient Sample
05000324/LER-1980-068-03, /03L-0:on 800909,during Reactor Startup,Hpci Sys Turbine Control Valve 2E41-V9 Would Not Open W/Auxiliary Oil Pump Running.Caused by Cracked Electronic Governor Reverse Actuator Assembly Plug.Plug & Affected Components Repla
05000293/LER-1980-066-03, /03L-0:on 800901,during Surveillance Testing, Diesel Fire Pump Was Declared Inoperable.Caused by Broken Governor Control Assembly.Assembly Repaired & Returned to Svc
05000259/LER-1981-016-01, /01T-0:on 810501,fire Pump Automatic Start Logic Found Inoperable During post-mod Tests.Caused by Wiring Being Removed from Terminal Points in Main Relay Panel 52. Permanent Wiring Replaced
05000260/LER-1981-018-03, /03L-0:on 810418,xenon Transient Observed Following Control Rod Sequence Exchange.Caused by Earlier Load Reduction in Conjunction W/New Control Rod Pattern. Control Rods Inserted & R Factor Brought within Limits
05000324/LER-1981-034-03, /03L-0:on 810225,discovered Reactor Core Isolation Cooling Sys Component Test Had Not Been Performed as Required.Caused by Failure of Operating Instructions to Provide for Rescheduling Tests Not Performed on Due Date
05000259/LER-1981-013-03, /03L-0:on 810424,Athens 161 Kv Line Tripped & Cooling Tower Transformer 1 de-energized.Caused by Rolled Current Transformer Leads B & C for Breaker 1928.Lead B in Breaker 1922 Loose.Rolled Leads Corrected
05000260/LER-1981-017-03, /03L-0:on 810409,unit 2 Reactor Zone Ventilation Sys Found Isolated.Caused by Temporary Alteration Which Bypassed Isolation During Relay Replacement.Controlled Shutdown Initiated
05000325/LER-1981-039-03, /03L-0:on 810409,while Preparing to Synchronize Main Generator to Sys Grid,Number 1 Diesel Generator Loss of Excitation Occurred,Making Diesel Generator Inoperable. Caused by Blown Fuse in Diesel PT Compartment.Fuse Replaced
05000324/LER-1981-039-03, /03L-0:on 810410,reactor Core Isolation Cooling Turbine Tripped.Caused by Loss of Turbine Speed Control Due to Open Voltage Dropping Resistor R1 in Electronic Governor Module.Resistor Replaced
05000301/LER-1981-001-03, /03L-0:on 810324,steam Generator Loop a Pressure Safeguards Actuation Setpoint Found Below Tech Spec.Caused by Setpoint Drift in Foxboro Model 63U-BC-OHCA-F Bistable. Bistable Replaced
05000317/LER-1980-053-01, /01T-0:on 800926,during Survey of Masonry Wall Design,Three Stacked Shielding Walls Were Identified as Having Possible Impact on safety-related Sys.Caused by Installation Prior to Implementing Mod Control Program
05000285/LER-1980-021-03, /03L-0:on 800910,transformer T4 of DG-1 Failed. Transformer Feeds Diesel Oil Immersion Heater & Alarm Relays.Caused by Moveable Armature Located on Immersion Heater Contractor.Armature Repaired
05000325/LER-1980-069-03, /03L-0:on 800827,during Normal Surveillance,Rhr Flow Indicator on Remote Shutdown Panel Demonstrated Erratic Indications W/Sys Shutdown.Caused by Mechanical Failure of Meter Movement.Movement Calibr & Returned to Svc
05000029/LER-1979-012-03, /03L-0:on 790312,during Normal Operation & Monthly Surveillance,Relay TDC-2 Operated at 12.52-s.Caused by Sticky Relay Mounted as Integral Part of Time Delay Relay, Due to Dust Buildup.Relay Replaced
05000293/LER-1980-065-03, /03L-0:on 800828,while Inerting Drywell,Discovered That Nitrogen Purge Supply Isolation Valve AO 5033B Would Not Close Via Control Switch.Caused by Defective Solenoid Vent Valve.Valve Repaired
05000324/LER-1981-037-03, /03L-0:on 810301,low Level Switch 2-B21-LIS-NO31D-3,model 4418C,actuated Outside Limit.Caused by Instrument Setpoint Drift.Switch Recalibr
05000324/LER-1980-089-03, /03L-0:on 801120,emergency Recirculation Fan 18-14-3450 Would Not Start During Control Bldg Emergency Filters Ventilation Sys Functional Test.Caused by Fan Motor Thermal Overloads Tripping.Thermal Overloads Reset
05000324/LER-1980-076-03, /03L-0:on 801119,switch 1 of 2-B21-PS-N021D Found Out of Calibr.Caused by Instrument Drift.Switch Recalibr & Returned to Operation.Instrument to Be Replaced
05000333/LER-1980-086-03, /03L-0:on 801110,fire Detection Sys for Reactor Core Made Inoperable to Allow Required Electrical Conduit Rerouting.Caused by Implementation of Required Fire Protection Mod.Fire Watch Established While Sys Repaired
05000293/LER-1980-087-03, /03L-0:on 801106,leak Rate in Drywell Calculated at 5.95 Gpm.Caused by Leaking Packing on B Recirculation Pump Discharge Motor Operated Valve 202-5B.Valve Repacked
05000282/LER-1980-033-03, /03L-0:on 801028,steam Flow Transmitter 1FT-464 Observed Reading Low.Caused by Zero Adjustment Shift in Barton Model 384 Differential Pressure Transmitter.Device Recalibr
05000348/LER-1980-070-03, /03L-0:on 801028,svc Water Bldg Train a Battery Sys Declared Inoperable Due to Low Cell Specific Gravity. Caused by Close Terminal Proximity & Poor Post Seal Design Allowing Formation of Acid Residue Which Shunted Current
05000317/LER-1980-061-03, /03L-0:on 801024,emergency Diesel Generator 11 Would Not Carry Greater than 2,500 Kw for Greater than 60 Minutes.Caused by High Cylinder Temp Due to Fouling of Injector Tips.Tips Replaced
05000293/LER-1980-085-03, /03L-0:on 801023,HPCI Sys Turbine Reached 150% of 4,000 Rpm Full Flow Speed,Rendering Sys Inoperable.Caused by Failure of Turbine Governor & Resistor in Speed Control Circuitry.Governor & Resistor Replaced
05000254/LER-1980-029-01, /01T-0:on 801103,during Suppression Chamber Mods to Make Weld fit-up,safety Relief Valve Line 1-3019E-8 Suffered 4-inch Crack at Pipe Penetration.Caused by Excessive Force.Pipe Will Be Repaired Before Startup
05000267/LER-1980-036-03, /03L-0:on 800706,during Rise to Power & Outpassing of Moisture from Circulator buffer-mid-buffer Upset & cross-tower Leakage of Buffer Helium Dryer Due to HV-21352. Valve Disc Replaced by Brass Model
05000298/LER-1980-023-04, /04T-0:on 800714,during Normal Operation,Condenser Cooling Water Outlet Temp Limit of 103 F Was Exceeded.Caused by Abnormally High River Temp & Removal of Several Rows of Low Pressure Turbine Blades
05000293/LER-1980-036-01, /01T-0:on 800806,found Hourly Fire Check of Auxiliary Offgas Bldg Not Performed on Continuous Basis Since 800707 While Fire Detection Units Were Inoperable. Caused by Communications Lapse Between Personnel
05000298/LER-1980-026-03, /03L-0:on 800701,during Routine Measurement of Identified Reactor Leakage,Drywell Equipment Drain Sump Flow Instrument Found Inoperable.Caused by Broken Slide Wire in Recorder & Blown Fuse in Power Supply.Fuse & Wire Replace
05000265/LER-1980-021-03, /03L-0:on 800914,core Spray Valve MO-2-1402-3A Would Not Reopen from Control Room.Caused by Sticky Torque Switch on Valve Operator.Valve Motor Operator Will Be Inspected During Next Outage
05000219/LER-1980-030-03, /03L-0:on 800716,during Valve Operability Test, Electromagnetic Relief Valve D Failed to Open.Plant Shut Down.Caused by Deficient Maint Procedure.Valve Plunger & Pilot Valve Operating Lever Clearance Adjusted
05000298/LER-1980-016-01, /01T-0:on 800707,during Normal Operation,D RHR Svc Water Booster Pump Taken Out of Svc for Longer than 24-h for Preventive Maint.Pump Overhauled After Tests Per ASME Section XI
05000296/LER-1981-017-03, /03L-0:on 810408,reactor Water Level Switch 3-LI-3-46B Was Removed from Panel 9-5 & Taken to Instrument Shop for Repair.Caused by Indicator Movement Sticking Due to Faulty Bearing.Indicator Repaired,Tested & Returned to Svc
05000320/LER-1980-053-03, /03L-0:on 801117,incore Thermocouples N-8 & N-9 Exhibited Erratic Behavior.Cause Undetermined.Situation Being Evaluated
05000293/LER-1980-051-03, /03L-0:on 800813,while Performing Surveillance Test,Reactor Water Level Instrument L1S 263-72B,switches 3 & 4,exceeded Setpoint Limit.Caused by Setpoint Drift. Instrument Recalibr & Returned to Svc
05000320/LER-1981-002-01, /01L-0:on 810126,emergency Diesel Generator B Determined Inoperable on 810119.Caused by Auxiliary Operator Not Completing Switching Order.No Corrective Action.Operator Counseled
05000325/LER-1981-015-03, /03L-0:on 810127,rod Block Monitor B Failed to Initiate RTGB Downscale Alarm & Rod Out Block at Downscale Alarm Setpoint.Caused by Mechanically Stuck Contacts in Control Relay K-2 in Cabinet Circuitry.Relay Replaced
05000325/LER-1980-090-03, /03L-0:on 801101,during Routine Surveillance, Containment Atmospheric Control Monitor 1-CAC-AT-1259 Was Observed Indicating Downscale.Caused by Instrument Drift. Monitor Recalibr Satisfactorily
05000260/LER-1980-059-03, /03L-0:on 801230,FR-77-16 Observed Downscale During Drywell Equipment Drain Sump Pump Operation.Caused by Shift in Model 555 GE Transmitter FT77-16 Zero Adjustment. Transmitter Recalibr,Tested & Returned to Svc
05000324/LER-1980-114-03, /03L-0:on 801229,low Level Switch 2B21-LIS-NO31D-3 Actuated Outside Tech Specs.Caused by Instrument Drift. Switch Recalibr
05000324/LER-1980-116-03, /03L-0:on 801231,pressure Switch 2-E11-PS-N010A Actuated Outside Tech Spec Limits.Caused by Instrument Drift.Switch Recalibr
05000254/LER-1980-033-03, /03L-0:on 801217,while Placing Standby Gas Treatment in Normal Standby Operation,Suction Valve MO-1-7503 Failed to Open from Control Room.Caused by Dirty Auxiliary Contacts.Contacts Were Cleaned & Replaced
05000267/LER-1980-077-03, /03L-0:on 801224,one Bearing Water Makeup Pump Removed from Svc During Normal Operation.Caused by Need to Repair Valve Leak.Valves Repaired & Pump Returned to Svc
05000333/LER-1980-094-03, /03L-0:on 801216,water Level Switch 02-3-LIS-58A Found Set Outside Tech Specs.Caused by Instrument Drift. Instrument Recalibr
05000260/LER-1980-055-03, /03L-0:on 801208,core Spray Discharge Pressure switch,2-PS-75-16,found Set Outside Tech Spec Limits.Caused by Mercroid Model DA-7004-804 Setpoint Drift.Switch Inspected & Calibr
05000293/LER-1980-094-04, /04T-0:on 801229,lab Rept Indicated Excessive Concentration of I-131 in Milk Sample Collected on 801120. Caused by Chinese Weapons Test.Consumption of Milk Poses No Threat to Health of Public
05000317/LER-1980-071-03, /03L-0:on 801220,turbine End High Pressure Bearing for Auxiliary Feed Pump 12 Exceeded Tech Spec Limit.Caused by Condensation in Oil.Bearing Replaced & Oil in Pump Bearings Changed
05000333/LER-1980-095-03, /03L-0:on 801217,reactor Core Isolation Cooling Sys High Steam Flow Switch 13-DPIS-84 Found Set Outside Tech Specs.Caused by Instrument Drift.Switch Recalibr
05000254/LER-1980-032-01, /01T-0:on 801211,during Installation of Hanger Per IE Bulletin 79-14,two 1/2-inch Anchor Bolt Holes Were Drilled Which Penetrated Primary Containment.Caused by Faulty Design.Plugs Welded in Holes
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
05000325/LER-1980-092-03, /03L-0:on 801220,reactor Vessel Conductivity Measured Over Tech Spec Level.Caused by Removal of Reactor Water Cleanup Sys from Svc for Valve Maint.Valves Repaired & Sys Returned to Svc
05000324/LER-1980-104-03, /03L-0:on 801128,containment Atmospheric Monitor 2-CAC-AT-1263 Tripped Due to Low Sample Flow.Caused by Moisture Accumulation in Monitor Sample Inlet,Air Dryer & Photohelic Unit.Moisture Drained & Purged
05000293/LER-1980-090-04, /04T-0:on 801215,analysis Rept Received Indicating Excessive Mussel Sample.Caused by Facility Operation
05000267/LER-1980-073-03, /03L-0:on 801121,effluent Discharge Antifoam Concentration Exceeded Tech Spec Limit for 3-h Period.Caused by High Blowdown Flow Rate.Procedure Will Be Implemented to Prevent Recurrence
05000333/LER-1980-079-03, /03L-0:on 801008,RCIC Sys Made Inoperable to Allow Repair of Steam Leaks on Manual Valves Associated W/Steam Line Drains.Leaks Caused by Normal Aging & Thermal Cycling. Valve Body to Bonnet Gaskets Replaced
05000306/LER-1980-030-03, /03L-0:on 801008,diesel Generator D2 Tripped on High Crankcase Pressure When Eductor Hose Failed.Caused by Burst Eductor Hose.Hose Replaced on Both Diesel Engines
05000293/LER-1980-068-03, /03L-0:on 800924,logging of Reactor Protection Sys Motor Generator Set Current & Voltage Was Inadvertently Terminated During Last Refueling Outage.Caused by Inadequate Station Procedures.Procedures 2.1.15 Revised
05000298/LER-1980-034-03, /03L-0:on 800908,during Routine insp,4160-volt Breaker RHR Id Found Not Capable of Closing Automatically. Caused by Failure of GE Magna Blast 4160 Vac Breaker to Charge Rendering Pump Inoperable.Switch Replaced
05000293/LER-1980-080-01, /01T-0:on 801031,reactor Vessel Relief Valve Rv 203-3A Opened.Caused by Nitrogen Regulator Valve Which Froze in Open Position.Drywell Instruments Will Be Operated by Compressed Air W/Nitrogen Supply Isolated
05000318/LER-1980-045-03, /03L-0:on 801017,failure of CTMT Particulate Radioactivity Detector Discovered.Caused by Open Termination within Connector Assembly for Detector Due to Age & Handling.Open Lead Repaired
05000293/LER-1980-082-03, /03L-0:on 801008,containment Isolation Valve MO-1001-34B Did Not Close When Actuated by Control Switch. Caused by Failure of Valve Torque Switch.Valve Replaced, Satisfactorily Tested & Returned to Svc
05000293/LER-1980-083-04, /04T-0:on 801103,analyses Rept Indicated That Concentration of Cs-137 Found in Cranberries from Manomet Point Bog on 800919 Was 354 Picocuries/Kg.Caused by Fallout
05000321/LER-1980-115-01, /01T-0:on 801031,util Notified That Nine Masonry Block Walls in Control Bldg Show Local Stresses Above Allowable Codes.Caused by Equipment Mounted on Walls After Original Installation.Walls Will Be Reinforced
05000271/LER-1980-037-01, /01P-0:on 801027,linear Indication Was Discovered by Ultrasonic Testing at Weld F3B on Reactor Cleanup Water Suction Line CUW-18.Cause Undetermined.Addl Examinations to Be Conducted by ASME
05000293/LER-1980-077-03, /03L-0:on 800930,excessive Moisture in Sample Lines Prevented Chemical Personnel from Obtaining Representative Sample of Drywell Atmosphere.Caused by Condensation Accumulating in Lines & Saturating C-19
05000293/LER-1980-076-03, /03L-0:on 800923,flow Integrator Fq 7032 for Drywell Floor Sump Pump Was Not Operating.Cause Undetermined
05000293/LER-1980-070-01, /01T-0:on 801010,480 Volt Breaker 52-204 Tripped Twice within 10 Minutes de-energizing 480 Volt Bus B14, Disabling Loop a of Rbccw.Cause Unknown.Breaker Closed,Bus Returned to Svc & Loop a Returned to Normal
05000306/LER-1980-026-03, /03L-0:on 800916,while Performing Fire Protection Mod Work in Auxiliary Feedwater Pump 22,workman Accidentally Bumped Overspeed Trip Mechanism,Tripping Valve & Making Pump Inoperable for 15 Minutes.Caused by Personnel Error
05000325/LER-1980-083-03, /03L-0:on 800926,during Normal Surveillance, Containment Atmospheric Monitor Oxygen Analyzer 1-CAC-ATH- 1259-2 Observed Indicating Upscale.Caused by Loss of Sample Flow to Analyzer Due to Excessive Condensation in Line
05000293/LER-1980-062-03, /03L-0:on 800903,following Surveillance Testing, a Diesel Generator Declared Inoperable Due to Snapped Fuel Line in Area of Diesel Generator Cylinder 9R.Caused by Severed Fuel Crossover T Type Connector
05000267/LER-1980-048-03, /03L-0:on 800901,during Surveillance Test,All Six Ultrasonic Noise Channels Were Found Inoperable.Microphone &/Or Transmitter Gain Had Been Reduced to Spurious Trips. Cause Not Stated.Gain Returned to Acceptable Levels
05000324/LER-1980-059-03, /03L-0:on 800903,during RHR Sys Flow Calibr, PT 55.8PC,square Root Transmitter 2E11-FY-3338 Found Not Responding Properly.Caused by Defective resistor,R5,in Transmitter Circuitry.Resistor Replaced
05000293/LER-1980-063-03, /03L-0:on 800828,reactor Coolant Leak Detection Air Sampling Sys (C-19) Declared Inoperable.Caused by Excessive Moisture in Sample Lines.Valve Packing Leak Will Be Overhauled During Refueling Outage
05000265/LER-1980-019-03, /03L-0:on 800829,recirculation Pump Motor Generator a Field Breaker Opened.Caused by Failure of Control Power Transformer for Recirculation Motor Generator A.Transformer Replaced
05000293/LER-1980-055-03, /03L-0:on 800821,motor Overload Alarm Was Received on Mo 1301-62 Valve in Reactor Cooling Isolation Sys.Caused by Valve Thermal Overload Device.Evaluation of Capacity Rating of Overloaded Device Being Conducted
05000267/LER-1980-044-03, /03L-0:on 800816,while Operating at 30% Power, Boiler Feed Pump a Was Removed from Svc Due to Unstable Governor Controls.Boiler Feed Pump B Was Out of Svc Also. Caused by Governor Worm Gear Being Loose on Shaft
05000267/LER-1980-045-03, /03L-0:on 800816,fitting on Hydraulic Oil Line Ruptured Spraying Oil on Hot Steam Pipes & Producing Heavy Smoke.Fitting Ruptured Due to Normal Usage & Was Replaced. Valve Group Was Isolated to Prevent Addl Oil Loss
05000317/LER-1980-048-01, /0LT-0:on 800903 During Maint for Control Room 12 Air Conditioner,Unit 11 Compressor Was Not Running & Later Tripped on Overload.Faulty Reset Switch Replaced & Procedures Revised to Require Check of Air Conditioner
05000293/LER-1980-060-03, /03L-0:on 800825,while Performing HPCI Sys Performance Test,Hpci Sys Declared Inoperable Due to Oscillating Steam Throttle Valve.Caused by Dirt Filtering Through Sys.Sys Recalibr
05000293/LER-1980-045-03, /03L-0:on 800804,after Injecting Furmanite Into Leaking Packing Gland on Reactor Core Isolation Cooling Outboard Isolation Valve,Valve Would Not Close Electrically. Probable Cause Was Improper Torque Setting
05000334/LER-1980-021, Has Been Cancelled
05000285/LER-1980-017-03, /03L-0:on 800804,during Normal Power Operation, Personnel Discovered Setpoint Selector Switches for RMO-61, Particulate Radiation Monitor,In Wrong Position.Caused by Personnel Error While Performing Test on Radiation Monitor
ST-HL-AE-1568, Forwards marked-up FSAR Pages Reflecting Changes in Response to NRC Verbal Questions on FSAR Chapter 14.2.Changes Will Be Submitted in Future FSAR Amend
05000334/LER-1980-008-01, /01T-1:on 800225,during in-plant Insp,Potential Overstress Condition of Cable Spreading Room Floor Indicated Due to Postulated Seismic Loading.Caused by Utilizing Underside of Floor to Higher Degree than Original Design
05000333/LER-1980-073-03, /03L-0:on 800815 During Surveillance,Offgas Radiation Monitor B Found Out of Calibr.Caused by Instrument Drift & Detector Aging.Adjusted & Restored Monitor to Operable Status 3 Days After Discovery
05000259/LER-1979-014, Has Been Cancelled
05000320/LER-1980-017, Has Been Cancelled
05000320/LER-1979-013, Has Been Cancelled
05000333/LER-1980-063-03, /03L-0:on 800717,during Normal Shutdown, Surveillance Revealed That Average Power Range Monitor E Indicated 48 When Required to Read Between 49 & 51.Caused by Instrument Drift.Monitor Recalibr
05000324/LER-1980-045-03, /03L-0:on 800707,during Normal Surveillance,A & D source-range Monitors Withdrawn from Core & Would Not Drive In.Caused by Detector Drive Motor Blown Fuses.Fuses Replaced & Monitors Returned to Svc
05000285/LER-1980-012-03, /03L-0:on 800708,during Performance of ST-RPS-3, F.2,discovered That Trip Unit 3 Setpoints Had Drifted Out of Spec in Nonconservative Direction.Caused by Normal Setpoint Drift.Setpoints Adjusted
05000317/LER-1980-033-03, /03L-0:on 800702,during Routine Test,Containment Air Cooler 14 Could Not Be Stopped or Shifted to Low Speed from Control Room.Caused by Relay 424 in Fan Controller Failing to Drop Out When de-energized
05000325/LER-1980-057-03, /03L-0:on 800703,during Performance of Standby Liquid Control Relief Valve Test,Valve 1-C41-FO29B Did Not Lift.Caused by Valve Setpoint Drift.Setpoint Adjusted & Penetrant Test Performed Satisfactorily
05000219/LER-1980-027-01, /01T-0:on 800716,during Tour by Plant Mgt & NRC Personnel,Reactor Bldg to Suppression Chamber Vacuum Breaker Inlet Pipe Found Covered W/Plastic.Caused by Personnel Error.Plastic Removed from Vacuum Breaker Inlet Opening
05000325/LER-1980-059-01, /01T-0:on 800710,util Informed by GE That Process Computer Was Not Using Correct Fuel Lengths When Calculating Max Total Peaking Factor.Cause Not Stated.Procedures Revised to Correct Tpf Ref Value
05000333/LER-1980-057-03, /03L-0:on 800628,during Normal Shutdown,One Cell in Each 24 Volt Battery for Diesel Fire Pump Failed to Meet Min Specific Gravity Requirements of Surveillance Test. Caused by Charger Being Out of Svc During Surveillance
05000333/LER-1980-058-03, /03L-0:on 800628,during Normal Shutdown Operations,Functional Tests of Average Power Range Monitor Instruments Found Not Conducted Per Tech Specs.Caused by Manual Scheduling of Computer Outage
05000301/LER-1980-007-01, /01T-0:on 800619,at Full Power,Test IT-04 Was Performed W/Emergency Diesel Generator 3D Out of Svc. Emergency Safeguards Train Equipment Would Have Been Inoperable on Loss of Ac Power.Caused by Personnel Error
05000346/LER-1977-019-01, /01T-0:on 771117,auxiliary Feedwater Valves AF 599 & AF 608 Found Closed,Rendering Steam & Feedwater Rupture Control Sys Pressure Switch Inputs Inoperable.Caused by Procedural Deficiency.Tests Revised
05000346/LER-1978-023-03, /03L-0:on 780224,temp Indication for Reactor Protection Sys Channel 2 Spiked Tripping Channel & Shut Down Reactor.Caused by Faulty Connector Due to Dirt on Contacts. Channel 2 Temp String Modules Removed & Connectors Cleaned
05000293/LER-1980-034-03, /03L-0:on 800701,HPCI Turbine Discharge Line Snubber S23-3-31 Found Severed.On 800716,snubber 23-3-36 Found Severed.Cause Not Stated.Analysis Initiated.Temporary Snubber Installed
05000313/LER-1978-006-03, /03L-0:on 780305,studs on Lower Steam Generator Primary Manway Cover Sheared Off.Caused by Crack of 90% of Stud Diameter.Studs Ultrasonically Checked for Cracks & One Removed
05000346/LER-1977-106-03, /03L-0:on 771206,two 345 Kv Air Circuit Breakers on K Bus Tripped Due to Fault on Oh Edison Co Beaver Line. Caused by Galloping Conductors on Transmission Line.Load Dispatcher Opened Air Breaker & Reclosed Circuit Breakers
05000346/LER-1978-073-03, /03L-0:on 780620,relay Wiring Error Found in Logic to Channel 2 Safety Features Actuation Sys.Caused by Mfg Defect:Relay Incorrectly Wired to Socket.Wiring Corrected & Verified by Surveillance Test 5031.07
05000346/LER-1978-043-03, /03L-0:on 780428,RCS Pressure in Safety Features Actuation Sys Channel 2 Failed Low After Monthly Test.Broken Wire Found on Test Switch Caused by Movement of Slightly Loose Switch in Panel.Switch Tightened & Wire Repaired
05000346/LER-1977-103-03, /03L-0:on 771204,reactor Protection Sys Channel 3, Loop 1 Hot Leg Temp Indicator Failed High.Cause Unknown. Channel 3 Cleaned,Tested & Declared Operational
05000346/LER-1978-010-03, /03L-0:on 780115, Reactor Coolant Pump Monitor on Channel 1 Found Out of Tolerance & Reactor Protection Sys Declared Inoperable.Caused by Defective Module.New Module Calibr & Installed
05000346/LER-1978-081-03, /03L-0:on 780719,required Surveillance Testing on Diesel Generators Not Performed.Caused by Procedures Inadequacy.Mod T-3029 to ST 5081.01 Written & Performed on 780720,verifiying Sureveillance Requirements
05000309/LER-1980-012-03, /03L-0:on 800506,during Monthly Surveillance Test Procedure,Low Power Safety Injection Loop 3 Header Stop Valve Failed to Operate as Required.Caused by Broken Weld in Coupling of Operating Extension Shaft
05000317/LER-1980-027-01, /01T-0:on 800520,following Routine Tube Cleaning on Saltwater Side of Svc Water Heat Exchanger 12,low Pressure Alarms Were Received on Subsys 11 & 12.Caused by Failed Tube in Exchanger 11 Instrument Compressor Cooler
05000333/LER-1980-045-03, /03L-0:on 800429,during Normal Operation,Rod to Block Monitor a Became Inoperable When Control Rod 26-19 Was Selected Due to Inadequate Number of Low Power Range Monitor Inputs.Caused by Age.Monitor Strings Will Be Replaced
05000309/LER-1980-011-03, /03L-0:on 800422,during Special Testing of Trip Matrix Portion of Reactor Protection Sys,One Set of Relay Contacts on Relay Would Not Open Reliably Upon de-energization of Relay.Cause Not Stated
05000339/LER-1980-001-03, /03L-0:on 800423,w/unit in Mode 6 Following Fuel Loading,Rhr Sys Inlet Valve MOV-2700 Ran Closed,Causing Loss of Operable RHR Loop.Caused by Blown Signal Comparator Card Power Supply Fuse in Process Control Sys.Card Replaced
05000267/LER-1980-021-03, /03L-0:on 800421,w/reactor Shut Down,Main Steam Pressure Low Instrument Discovered Inoperable.Caused by Bad Connection Due to Dirty Contact.Contacts Cleaned & Module Returned to Svc
05000346/LER-1980-038-03, /03L-0:on 800420,during Performance of Svc Water Sys Refueling Relief Valve Test,Svc Water Discharge Header Pressure Relief Valve Was Found Discharging Continuously & Would Not Reseat.Caused by Failure of Adjusting Ring
05000318/LER-1980-024-03, /03L-0:on 800417,during Containment Entry ,Leak in Middle Seal Instrument Line Flexible Hose Discovered.Cause Unknown.Failed Part Is Inside Containment Bldg & Is Still Radiologically Contaminated
05000317/LER-1980-025-04, /04T-0:on 800307,environ Samples Collected & Analyzed in Accordance W/Ets,Confirmed Measured Levels of Radioactivity in Excess of Ten Times Background Value.Caused by Use of More Sensitive Background Value
05000309/LER-1980-008-03, /03L-0:on 800321,during Special Testing of Trip Matrix Portion of Reactor Protective Sys,Found One Set of Relay Contacts on One Matrix Relay Would Not Open Reliably Upon de-energization.Cause Not Stated
05000267/LER-1980-017-03, /03L-0:on 800311,w/plant Shut Down Due to Loss of Main Cooling Water Return Line,Plant Liquid Effluent Sample Required by SR Nr 1.1 Not Taken.Caused by Preempted Time Due to Plant Upset.Sampling Resumed on Next Shift
05000295/LER-1979-089, Has Been Cancelled
05000304/LER-1980-005, Has Been Cancelled
05000295/LER-1980-006, Has Been Cancelled
05000295/LER-1980-004, Has Been Cancelled
05000304/LER-1979-048, Has Been Cancelled
05000295/LER-1979-064, Has Been Cancelled
05000295/LER-1979-067, Has Been Cancelled
05000304/LER-1979-047, Has Been Cancelled
05000293/LER-1977-009-03, During Standby Operation, HPCI Was Inoperable for 5-h.Caused by Burnt Out Undervoltage Coil in Breaker for Motor Operated Valve Mo 2301-3,steam Supply Valve to Hpci.Caused by Overheating
05000267/LER-1980-029-03, /03L-0:on 800602,at Approx 60% Power,Reactor Bldg Pressure Could Not Be Maintained Subatmospheric.Caused by Frozen Air Line to Reactor Bldg Louver Pneumatic Actuator Due to Liquid Nitrogen Proximity
05000293/LER-1980-025-03, /03L-0:on 800602,fire Detection Alarm from HPCI Quadrant Sounded in Control Room on Panel C-94.Roving Fire Patrol Initiated & Immediate Investigation Conducted.Caused by Leak at Flange on HPCI Drain Line Valve AO2301-29
05000301/LER-1980-005-03, /03L-0:on 800609,during Training Walkdown of Safeguards Electrical Supply Cabinets,Noted That Tie Breaker Between AO5 & AO6 Safeguards Buses Was Shut.Probably Caused by Improper Electrical Lineup After Loss of Ac Test
05000293/LER-1980-027-03, /03L-0:on 800605,stack Gas Grab Sample Pump P143 Tripped.Caused by Binding in Pump Due to Accumulation of Dirt.Pump Refurbished & Returned to Svc
05000285/LER-1980-011-03, /03L-0:on 800528,during 1980 Refueling Outage Type B & C Containment Leak Rate Tests,Total Leakage Exceeded 0.6La Limit.Caused by Leaking Fuel Transfer Tube, Electrical,Mechanical Sleeve & Piping Penetrations
05000267/LER-1980-027-03, /03L-0:on 800603 to 11,three Separate Instances of Reactor Operation Took Place W/Inoperable Class 1 Shock Suppressors.Caused by Rotated Reservoir,Low Oil Level Due to Cracked Fitting & Piston Rod Seal Leak
05000267/LER-1980-025-03, /03L-0:on 800523,during 800523-30,total Primary Coolant Oxidants Were Greater than 10 Ppm W/Average Core Outlet Temp Above 1,200 F on Six Occasions.Caused by Moisture Increase & Carbon Monoxide & Dioxide Combination
05000293/LER-1980-021-04, /04T-0:on 800508,algae Sample from Discharge Outfall Area Contained Reportable Concentration of Co-60, According to Yankee Environ Lab 800616 Analysis Rept.Cause Not Stated
05000333/LER-1980-054-04, /04L-0:on 800530,during Normal Shutdown,Both Recorders for Gaseous Release Rate from Reactor Bldg Ventilation Sys & Plant Process Computer Were Out of Order During Same 16-h Period.Caused by Personnel Error
05000267/LER-1980-028-03, /03L-0:on 800520,during Circulating Water Sys Chlorination,Total Chlorine Residual Exceeded Limit.Caused by Chlorine Demand Decrease Following Steady Increase. Chlorination & Blowdown Reduced
05000306/LER-1980-016-03, /03L-0:on 800529,during Instrument Calibr, Instrument Was Dropped on Trip Throttle Valve Linkage, Tripping Valve & Making Pump Inoperable for 3 Minutes. Caused by Personnel Error
05000285/LER-1980-006-01, /01T-0:on 800415,as Required by IE Bulletin 79-01B,util Has Been Obtaining & Reviewing Test Data on Electrical Equipment.Samples Failed to Meet Acceptance Criteria.Caused by Steam & Moisture in Environ
05000213/LER-1980-009-01, /01T-0:on 800516,while Performing Local Leak Rate Testing,Leakage Rate Exceeded Tech Spec Limits.Caused by Failure of Component Cooling Water Check Valve Due to Warped Seating Surface.Surfaces Reworked
05000285/LER-1979-007-01, /01T-3:on 800305,during Review Required by IE Bulletin 79-01,Barksdale Pressure Switch Not Found Environmentally Qualified.Caused by Switch Not Being Properly Specified for Intended Svc.Switch Will Be Upgraded
05000293/LER-1980-009-04, /04T-0:on 800310,facility Received Analyses Rept from Util Lab Indicating Reportable Concentrations of Cr-51 & Co-60 in Sample of Mussel Taken from Facility Discharge Canal.Cause Not Stated
05000321/LER-1980-024-03, /03L-0:on 800229,while Performing Manual Start on 1C Diesel Generator W/Reactor at 99%,discovered Manual Voltage Regulator to Be Inoperable.Caused by Failure of Diodes Supplying Voltage to Manual Adjusting Motor
05000271/LER-1980-009-03, /03L-0:on 800228,during Surveillance,Testing,Rhr Svc Water Pump P-8-1C Failed to Start.Caused by Broken Lead on Closing Coil in Circuit Breaker.Circuit Breaker Replaced
05000298/LER-1979-005-03, /03X-1 on 790216:reactor Recirculation Motor Generator Set a Tripped During Normal Operation.Caused by Failure of Level Switch NBI-LIS-58A Due to Corrosion. Corrosion Cleaned from Inside Switch Case & Switch Replaced
05000333/LER-1980-050-03, /03L-0:on 800509,MSIV Failed Leak Tightness Limit of Tech Spec.Caused by Packing Leakage Due to Age.Valve Repacked
05000271/LER-1980-018-01, /01P-0:on 800611,leakage Developed in Feedwater Line.Plant Shutdown to Cold Condition Initiated.Caused by Failure of Feedwater Check Valve Bonnet Seal.Seal Will Be Repaired Prior to Resuming Operation
05000285/LER-1980-009-99, /99T-0:on 800522,during Maint on Stack Iodine Process Monitor,New Sensitivity Calibr Was Required.Caused by Use of Wrong Calibr Procedure.Training Will Be Conducted to Ensure Familiarity W/Procedures
05000309/LER-1980-013-03, /03L-0:on 800507,during Routine Power Operation, Auxiliary Operator Noticed S-charging Pump Was Not Lined Up W/Required Degree of Separation.Caused by Personnel Error. Surveillance Test Procedure Revised
05000333/LER-1980-033-03, /03L-0:on 800409,during Normal Operation,Diesel Fire Pump Was Intentionally Made Inoperable for Approx 45 Minutes.Caused by Need to Replace Engine Cooling Heat Exchanger Goose Neck,Corroded Due to Normal Wear & Tear
05000333/LER-1980-031-03, /03L-0:on 800405,drywell to Torus Differential Pressure Did Not Meet 1.75 Psi Requirement of Tech Spec. Caused by Rapid Temp Decrease in Sys Cooling Drywell.Reactor Bldg Cooling Water Temp Restored
05000293/LER-1980-015-03, /03L-0:on 800401,during Performance of Surveillance Test,Dry Chemical Fire Protection Sys Failed to Automatically Initiate.Caused by Erratic Pyrotronics, Dtf 190 heat-actuated Device.Unit Replaced
05000336/LER-1980-020-03, /03L-0:on 800429,during Power Operation,Rcs Pressure Was Too Low Due to Stuck Pressurizer Spray Valve & Reactor Tripped on Low Steam Generator Level During Load Reduction.Caused by Loose Valve Seat.Valve Repaired
05000267/LER-1980-019-03, /03L-0:on 800327,operation in Degraded Mode of Limiting Condition 4.2.10 Occurred on Six Occasions & Reactor Dewpoint Limit of Limiting Condition 4.2.11 Was Exceeded Once.Caused by Problem W/Buffer Helium Sys
05000267/LER-1980-018-03, /03L-0:on 800327,w/plant Operating at Approx 51% Thermal Power,One Loop 2 Hot Reheat Header Activity Monitor Found Inoperable.Caused by Failure of Motorola Chip (MPS-66A)in Operational Amplifier to Detector Preamp
05000321/LER-1980-031-03, /03L-0:on 800330,while Operating at 99.8% of Rated Mwt,Main Stack Radiation Monitor Sample Pump Failed.Cause Attributed to Moisture Swelling Carbon Vanes in Pump,Locking Pump.Sampling Procedure Will Be Revised
05000267/LER-1980-015-03, /03L-0:on 800320,during Operation at Approx 60% Power,Emergency Feedwater Header Supply to Loop 2 Helium Circulation Water Turbine Drives Was Isolated to Repair Leaking Pressure Control Valve.Caused by Loose Block Bolt
05000317/LER-1980-002-04, /04T-0:on 800322,instantaneous Hourly Average for Condenser Temp Rise Observed in Excess of Tech Spec Limit. Caused by Operator Inattention to Temp Rise Across Condenser & Environ Conditions
05000338/LER-1980-035-99, /99X-0:on 800313,Westinghouse Informed Util of Potential for Supplied Control Rod Guide Tube Support Pins to Break Due to Stress Corrosion Cracking.Caused by Low Solution Heat Treatment Temp
05000318/LER-1980-019-02, /02L-0:on 800312,while Performing QC Insp,Cable A2Y0929P Was Found Incorrectly Routed,Which Violated Cable Separation Criteria.Caused by Personnel Not Following Designed Routing of Cable.Temporary Cable Installed
05000366/LER-1980-025-03, /03L-0:on 800308,during Shutdown,While Performing Rhr(Lpci) Pump Start Timers Calibr,Relay 2E11-K75A Setpoint Exceeded Tech Specs.Caused by Setpoint Drift.Relay Recalibr
05000318/LER-1980-010-03, /03L-0:on 800224,during Surveillance Testing, Control Element Assemblies 31 & 34 Dropped Into Core.Caused by Fault in Timer Module.Module Replaced
05000366/LER-1980-047-03, /03L-0:on 800405,while Performing Remote Shutdown Panel Instrument Checks,Torus Water Level Instrument 2T48-R070 Found Downscale.Caused by Technician Failing to Verify Markings of Transmitter 2T48-N070 W/Proper Tubing
05000320/LER-1979-015-13, /13L-0:on 790328,while Investigating Leakage of Radwaste & Makeup Sys,Personnel Received Radiation Doses in Excess of Allowable Quarterly Limit.Individual Exposures Less than Five man-rem.Sampling & Area Surveys Suspended
05000318/LER-1980-025-03, /03L-0:on 800428,during Steady State Operation, Channel a Trip Functions Were Bypassed in Accordance W/Tech Specs.Bypass Necessary to Determine Cause of Erratic Channel a Computer Flow Alarms.Caused by Defective Thermocouple
05000282/LER-1980-010-03, /03L-0:on 800311,during Surveillance Test, Containment Isolation Valve 11 Opened at 0.57 Psi.Caused by Apparent Drift in Barton Model 288A Differential Pressure Switch.Setpoint Adjusted & Valve Retested Satisfactorily
05000271/LER-1980-012-01, /01T-0:on 800328,during Seismic Analysis Required by IE Bulletin 79-14,discovered That Pipe Supports RHR-H-83 & RSW-H-168 May Be Inadequate to Support Seismic Loads. Caused by Deviations from Hanger Design Details
05000318/LER-1980-018-03, /03L-0:on 800311,during Routine Insp Tour,Watch Stander Noticed Leak Weld on 23 Charging Pump Suction Relief Valve Causing Degradation of Sys Designed to Contain Radioactive Fluid.Caused by vibration-induced Metal Fatigue
05000318/LER-1980-017-03, /03L-0:on 800316,saltwater Svc Water Heat Exchanger 22 Was Taken Out of Svc.Caused by Need to Repair Tube Leak.Tube Leak Found & Plugged
05000317/LER-1980-014-03, /03L-0:on 800310,during Surveillance Testing, Reactor Core Drain Tank & Quench Tank Oxygen Sample Valves Failed to Shut on Safety Injection Actuation Signal.Caused by Corrosion on Output Relay Terminals
05000267/LER-1980-013-03, /03L-0:on 800310,during 58% Thermal Power Operation,Indicated Flow for Two Low Level Primary Coolant Dewpoint Moisture Monitors Discovered Less than Requirements.Caused by Inaccurate Flow Elements
05000324/LER-1980-024-03, /03L-0:on 800311,while Decontaminating Torus in Preparation for Mods,Coating Found Blistered Under Normal Water Line.Caused by Demineralized Water Entrapped Between Steel Liner & Coating.Samples to Be Tested in DBA Environ
05000267/LER-1980-012-01, /01T-0:on 800311,while Facility Was Operating at Less than 2% Power,Orifice Valves Not Set for Equal Flows & Temp Limit Was Exceeded.Caused by Inability to Close Orifice Valve to Equal Flow Position.Valve Freed Up
05000254/LER-1980-003-03, /03L-0:on 800206,while Performing Procedure Qos 1000-3,RHR to Suppression Chamber Dump Valve,Mo 1-1001- 36A,circuit Breaker Tripped Out.Caused by Burned Out 480/120-volt Transformer in Circuit Breaker Cabinet
05000324/LER-1980-010, Supplemental LER 80-010/03L-1:on 800114,during Normal Plant operation,OD-1 Determined That Max Critical Power Ratio Was Below Tech Specs for Bundle 43-28.Caused by Problems W/Low Power Range Monitor & Core Flow Input.Power Redu
05000318/LER-1980-004-03, /03L-0:on 800121,during Steady State Operation, Received Indication of Several Spurious Loss of Load Trips on Channel B.Cause of Event Unknown.Troubleshooting Revealed Electrical Noise on Input Leads
05000318/LER-1980-005-03, /03L-0:on 800122,five Channel B Trip Units Were Bypassed Due to Spurious High Power Levels.Caused by Noise from Excore Nuclear Instrument Upper Subchannel Detector. Troubleshooting Planned for Next Cold Shutdown
05000324/LER-1980-016-03, /03L-0:on 800117,during Normal Operation,Torus Level Recorder 2-CAL-LR-2602 Differed from Actual Torus Level.Caused by Missing Screw in Mounting Assembly,Causing Loose Chart Drive Gear Mechanism.Screw Replaced
05000325/LER-1980-010-03, /03L-0:on 800122,while Performing Main Steam Line High Radiation Functional Check,Drawer 1D12-RM-K603B Found Out of Calibr.Instrument Drift Is Recurring Problem. Drawer Recalibr & Returned to Svc
05000029/LER-1980-002-03, /03L-0:on 800116,during Normal Operation,Primary Vent Stack Iodine Monitor Failed.Caused by Natural end-of- Life of One Pump Motor Bearing.Pump Motor Replaced
05000318/LER-1980-003-03, /03L-0:on 800110,repairs to Number 21 Diesel Generator Jacket Coolant Sys Required Diesel Be Out of Svc. Caused by Leaking Gasket on Jacket Cooling Water Discharge Header.Leak Located & Repaired
05000334/LER-1978-054-03, /03L-0 on 781005:During Surveillance Test on Containment High Pressure Bistable,The Setpoint Was 2.3 Lbs Instead of 2.0.Caused by Faulty Elco Connector on Loop Signal Comparator.Comparator Was Replaced
05000325/LER-1978-081-03, LER 78- 081/03L-0 on 781028:main Steamline Drain Isolation Valve B21-F019 Failed to Operate Due to Faulty Brush Holder in Valve Motor.Motor Replaced & Valve Declared Operable
05000277/LER-1979-032-01, /01T-1 on 790626:insp of Seismic Class I Supports Revealed 92 W/Safety Factors of Less than 5,w/8 Having Safety Factors of Less than 1.Caused by Inadequate Design. All Mods Completed by 790719
05000267/LER-1980-009-01, /01T-0:on 800225,while in Shutdown Condition,Test Evaluation Determined Bistable Trip Modules,When Used W/Mtu for Calibr of Process Trips,Induced Calibr off-set Which Could Allow Trips Outside Tech Specs.Bistables Recalibr
05000301/LER-1980-001-01, /01T-0:on 800221,during Full Power Operation, Momentary Loss of Red Instrument Bus Occurred,Resulting in Power Range Channel N41 Failing Low.Caused by Faulty Capacitor in 2DY01 Power Supply.Capacitor Replaced
05000254/LER-1980-004-03, /03L-0:on 800215,while Performing Reactor low-low Water Level Calibr Test,Procedure QIS-11,level Switch LIS-1-263-72A Failed.Caused by Slight Misalignment of Mercury Wetted Magnetic Switch W/Actuating Magnet
05000317/LER-1980-004-03, /03L-0:on 800110,low Flow Alarm Received for Containment Particulate & Gaseous Radiation Monitor Sys. Caused by Gasket Leakage at Particulate Detector Sample Psig.Gaskets Replaced & Flow Restored to Normal
05000336/LER-1978-014-03, /03L-0 on 780617:while Performing Monthly Control Element Assembly Surveillance Testing,Assembly 2 Dropped to Zero Steps from 178 Steps.No Component Failures Causing Control Element Assembly to Drop
05000277/LER-1978-038-01, /01T-0 on 780908:one Point on Piping Outboard MO-12-15 Had Stress During DBE Above Code Allowable. Restraint to Be Added to Code
05000324/LER-1978-083-03, /03L-0 on 781208:chloride Leak detector(CDD-CIT-1) Was Found Inoperable During Periodic Test Due to Faulty Interrupter Switch in Recording Unit.Switch Was Replaced & Chloride Leak Detector Declared Operable
05000267/LER-1979-005-03, /03L-0 on 790209:during Semiannual Loss of Outside Electrical Power Test,Output Circuit Breaker Did Not Close.Cause Unknown.Breaker Replaced W/Equivalent Spare
05000317/LER-1979-027-03, /03L-0 on 790719:metrascope Position of Control Element Assemblies Was Lost.Caused by Faulty Metrascope Power Supply.Faulty Components Replaced,Setpoints Calibr & Alarms Cleared
05000267/LER-1979-021-03, /03L-1 on 790720:during Review of Surveillance Tests,Discovered That Halon Fire Suppression Sys Surveillance Test for Second Quarter Not Performed.Caused by Inadequate Control & Direction Re Refueling Work Load
05000272/LER-1979-052-01, /01T-0 on 790809:review of OL Amend 4 Indicates That 12 Inch Per Minute Rise Rate Restriction May Reduce Margin for Loss of Normal Feedwater & Main Feedline Rupture Accident.Nrc Should Issue OL Mod
05000267/LER-1979-023-03, /03L-0 on 790727:while Performing Normal Surveillance,Fixed Feedwater Low Flow Switch Found Inoperable. Caused by Component Failure from Normal Wear. Module Was Repaired,Reinstalled & Retested Satisfactorily
05000317/LER-1979-015-03, /03L-0 on 790507:low Pressure Safety Injection Pump Stopped for 15 Minutes Due to Spurious Recirculation Actuation Signal.Caused by Voltage Transient.Test Procedures Revised
05000324/LER-1978-064-03, /03L-1 on 780820:during Testing 3 Hydraulic Snubbers Found Inoperable.Snubber E11-95SS20 Was Low on fluid,G41-22SS85 Was Mechanically Disconnected & E11-37SS95 Had Cracked Support.Each Was Repaired or Replaced
05000324/LER-1978-077-03, /03L-0 on 781215:during test,E41-DPIS-N005 Failed to Operate.Caused by Inoperable Relay Due to Faulty Maintenance Work;Relay Wire Was Left Unterminated
05000324/LER-1979-037-03, /03L-0 on 790519:control Panel Instrument 2-CAC-ATH-1263-2 Gave Downscale Reading & 2-CAC-ATH-1259-2 Was Out of Calibr.Caused by Being Out of Calibr.Both Instruments Recalibr & Returned to Svc
05000265/LER-1979-009, Forwards LER 79-009/03L-0.Corrects Docket Number of Original Forwarding Ltr
05000325/LER-1979-026-03, /03L-1 on 790507:during Normal Operation,Oxygen Analyzer Indicated High Oxygen Concentration.Caused by Split Hose from Air Sample Inlet Fitting.Tubing Repaired & Replaced
05000271/LER-1978-009-03, /03L-0 on 780331:during Control Rod Testing, Rod Block Monitor a Was Bypassed Several Times.Caused by Supervisory Misunderstanding.Misunderstanding Clarified & Precautionary Procedures Added
05000324/LER-1979-039-03, /03L-0 on 790519:leak Rate Test on Airlock Not Completed within 72-h.Caused by Administrative Oversight. Test Completed Satisfactorily
05000325/LER-1979-014-03, /03L-0 on 790519:operator Noted Containment Atmosphere Dilution Less than 4,350.Caused by Frozen Pressure Control Valve.Regulator on Pressure Control Valve Adjusted
05000318/LER-1978-030-03, /03L-0 on 780828:discovered Control Element Assembly Motion Inhibit Not Operable for Position Deviation. Caused by Bad K2 Relay on Relay Card.Relay Replaced & Motion Inhibit Returned to Svc
05000309/LER-1979-010, /03X-1 on 790315:corrects Statement Contained in LER 79-010/03L-0.Contrary to Statement,Release Did Occur & Was Reported in LERs 79-008/03L-0 & 79-009/03T-0
05000325/LER-1979-027-03, /03L-1 on 790503:reactor Core Isolation Cooling Inboard Steam Isolation Valve 1-ES1-F007 Would Not Open. Cause Not Ascertained.Breaker for F007 Valve Cycled Several Times Locally & Auxiliary Contacts Cleaned
05000334/LER-1978-064-03, /03L-0 on 781222:comparator in 1A Main Steam Flow Instrumentation Channels Inoperable;Channel Bistables Tripped.Caused by Failure of Comparator
05000334/LER-1978-065-03, /03L-0 on 781228:during a Surveillance Test on Control Room Emergency Habitability Sys,Sys Could Not Maintain the Room at Required 1/8 Inch Wc Above Outside Atmosphere.Caused by Leaks in Control Room
05000325/LER-1979-028-03, /03L-0 on 790504:during Reactor Startup,Operator Had Neither Full in Nor Full Out Indications on Rod 22-47.Out Indication Now Works & No Problem Found.Rod Can Not Presently Be Driven in to Check in Indication
05000324/LER-1979-007-01, /01T-0 on 790227:during Reactor Annulus Pressurization Analysis,Pipe Whip Restraint in Each Unit Did Not Conform.Caused by Improper Design of Restraint.Architect & Owner Will Design Addl Restraint
05000318/LER-1978-044-03, /03L-0 on 781203:reactor Protection Sys Channel C T-cold Was Erratic & Read Approx 4 F Higher than Pressure Other Channels.Caused by Bad Delta T-thermal Margin/Low Pressure Calculator Mode Switch
05000271/LER-1980-004-03, /03L-0:on 800109,power Supply Overheated & Failed, Resulting in Loss of All Rod Position Indication,Rpis Alarm,All Rod Drift Alarms,Rwm Rod Block & Overtravel Alarm. Caused by Failure of Cooling Fan in Power Supply
05000271/LER-1980-006-01, /01T-0:on 800122,received Low Flow Alarm on Off Gas Sampling Sys.Flow Disturbance Rendered Both Radiation Monitors 17-150A & B Inoperable.Apparently Caused by Flow Blockage.Flow Increased,Clearing Blockage
05000324/LER-1979-004-03, /03L-0 on 790110:chart Recorder for CAC-AT-1259 Was Reading Inaccurately,Since Sample Pump for Drywell Monitor CAC-AT-1259 Was Producing Poor Flow,Due to Malfunction
05000267/LER-1980-003-03, /03L-0:on 800110,while Reactor Was in Shutdown Condition,Three Hangers Found Impaired,Which Caused 21 Sys to Be Impaired.Caused by Failure to Reinstall Hangers Following Removal for Sys Mod.Hangers Will Be Modified
05000318/LER-1980-002-03, /03L-0:on 800107,refueling Water Tank Narrow Range Level Indicator Was in Alarm W/Low Level,But Instrument Did Not Indicate Alarm Conditions.Caused by Faulty Indicator Alarm light-emitting Diode.Diode Replaced
05000317/LER-1980-001-03, /03L-0:on 800104,high Pressure Safety Injection Loop 12A Stop Would Not Move to Throttled Position.Caused by Loose Termination on One Electrical Lead Terminating at Valve Torque Switch.Terminal Screw Tightened
05000317/LER-1980-006-03, /03L-0:on 800103,while Performing Routine Surveillance Test,Control Element Assembly 60 Was Dropped Into Core.Cause Unknown.All Parameters Found Normal & No Problems Encountered.No Further Action Anticipated
05000282/LER-1980-002-03, /03L-0:on 800107,during Surveillance Test of Diesel Generator D-1,relay Misoperation Occurred Which Would Have Prevented Automatic Synchronization of Generator Onto Bus 15.Caused by Stuck Relay Plunger.Plunger Freed
05000324/LER-1980-008-03, /03L-0:on 800110,while Performing Reactor Core Isolation Cooling Instrument Check,Reactor Core Isolation Cooling Trip & Throttle Valve MOV-V8 Would Not Trip.Caused by Burned Solenoid.Solenoid Repaired
05000267/LER-1979-064-03, /03L-0:on 791205,during Surveillance Test on Class 1 Hydraulic Snubbers,Three Snubbers Found Inoperable & Two Installed W/Incorrect Orientation.Caused by Piston Ring Being Out of Tolerance on One Snubber
05000293/LER-1979-042-03, /03L-0:on 791101,oxygen Analyzer Valves A0-5065- 10,12,15,16,17,23 & 26 Did Not Meet Primary Containment Isolation Timing Requirements.Caused by Faulty Position Indication Lights on A0-5045-12 & 15
05000317/LER-1979-017-03, /03L-0 on 790515:during Overspeed testing,12 Diesel Generator Auxiliary Blowers Failed,Rendering Diesel Inoperative.Caused by Interference Between Lobes of Blower. Blower Returned to Vendor for Rebuilding
05000219/LER-1979-032-03, /03L-0:on 790914,leaks Discovered in Both Containment Spray Sys.Caused by Corrosion Accelerated by Galvanic Action.Matl Change in Nipple Recommended
05000366/LER-1979-037-03, /03L-0 on 790517:during Cold Shutdown,Technicians Inadvertently Set Isolation Trip Setpoint of Alarm Units 2G31-K603A&B for Leakage Flow of 134 Gallons/Minute. Caused by Incorrect Procedure.Procedure Revised
05000267/LER-1979-016-01, /01T-0 on 790521:punch Gap of Pcrv Rupture Disc M-11702 Found Out of Tolerance W/Vendor Specs.Caused by Undocumented Change of Punch Gap Specs.Tolerances Returned to Original Specs
05000325/LER-1979-037-03, /03L-0 on 790515:average Power Range Monitor a Upscale Rod Block Alarm Out of Spec High. Caused by Instrument Drift.Instrument Setpoint Lowered
05000348/LER-1978-090-03, /03L-0 on 781206:while Reviewing FNP-1STP-1.0, Discovered Tech Spec 4.5.2.a.b Requirements Were Not Being met.V8132A&B Were Open as Required But Breakers to Valid Operators Were Not Locked Open,Due to Personnel Error
05000318/LER-1978-046-03, /03L-0 on 781217:during Surveillance,Noted That Control Element Assembly 18 Would Not Electrically Drive Down in Manual Individual or Manual Group.Caused by Inoperable Timer for Assembly
05000317/LER-1979-081-03, /03L-0:on 791225,containment Air Particulate & Gaseous Radiation Monitor Pump Tripped Off Due to Low Air Flow.Cause Undetermined.Air Flows Realigned & Readjusted. Operating Instructions Being Modified
05000293/LER-1980-001-01, /01T-0:on 800123,fire Hazard Analysis Determined That Fire in Electrical Raceways in Several Areas of Plant Would Jeopardize Redundant Div of ECCS Sys.Cause Not Stated. Mods Planned to Be Completed by Oct 1980
05000317/LER-1979-077-03, /03L-0:on 791213,control Room Air Conditioning Compressor 12 Tripped & Became Inoperable.Caused by Displacement of Crankcase Oil to Evaporator Coil Due to Operation at Low Ambient Temp.Oil Recovered
05000321/LER-1979-106-03, /03L-0:on 791216,during Shutdown,Hpci Steam Supply Valves Closed at 116 Psig,Isolating HPCI & Violating Tech Specs.Cause Not Stated.Design Change Has Been Submitted to Change Setpoint of Pressure Switches
05000317/LER-1979-079-03, /03L-0:on 791219,high Differential Pressure Detected Across Filters of Fuel Pool Exhaust Fans.Caused by Excessive Buildup of Dirt on Filter Media.Maint Procedure 1-32-M-M-3 Initiated to Inspect Filters Monthly
05000325/LER-1979-108-03, /03L-0:on 791211,during Normal Plant Operation, Drywell Pressure Indicator CAC-PI-3341 Was Reading 3 Psig W/Normal Pressure of 0.5 Psig.Caused by Indicator Zero Being Out of Tolerance.Indicator Recalibr
05000324/LER-1979-105-03, /03L-0:on 791201,while Replacing Indicating Light Bulb During Rod Block Monitor Rod Block Test,Bulb Broke & Rod Block Monitor B Tripped.Caused by Base of Broken Bulb Coming in Contact W/Ground.Bulb Replaced
05000271/LER-1979-034-01, /01P-0:on 791211,during Seismic Analyses of Seismic Class 1 Pipe Supports,Discovered That Pipe Supports in Portion of Two Sys May Not Support Seismic Loads.Caused by Incorrect Design or Application of Supports
05000325/LER-1979-083-03, /03L-0:on 791024,reading on Torus Level Instrument 1-CAC-LT-3342 Was Six Inches Low.Caused by Inaccurate Calibr Resulting from Debris in Sight Glass.Calibr Instruction Revised to Include Cleaning of Sight Glass
05000325/LER-1979-073-03, /03L-0:on 790930,while Performing Control Rod Operability Check,Control Rod 34-43 Had No Indication at Notch 47.Caused by Problem Located in Prototypic Inlet Piping.Engineering Work Request Written
05000338/LER-1978-134-03, /03L-0 on 781223:trip Status Indication Was Not Received When Turbine Stop Valve TV-3 Was Closed During Periodic Test 1-Pt-34.3.Caused by Limit Switch for Turbine Stop Valve TV-3 Out of Adjustment
05000267/LER-1979-046-03, /03L-0:on 791011,noted That Sequence of Manual Switching of Primary Coolant Low Level Dew Point Moisture Monitors Can Result in Degraded Mode of Limiting Conditions for Operation.Sys Operating Procedure Revised
05000325/LER-1979-078-03, /03L-0:on 791011,valve Actuation Switch Jammed, Making Torus Suction Inoperable.Cause Not Stated.Actuation Switch Replaced from Stock.Work Request Been Submitted to Determine If Generic Problem Exists
05000309/LER-1979-021-03, /03L-0:on 790918,during Cold Shutdown Test of Containment Spray Pump,Operator Observed Decrease in Pump Amps & Discharge Pressure.Caused by Personnel Error.Spare Pump Placed in Svc & Appropriate Personnel Reprimanded
05000333/LER-1979-071-01, /01T-0:on 791004,pipe Stress Reanalysis Revealed That Pipe Support H15-124 on Emergency Svc Water Return Piping Was Inoperable.Cause Not Stated.Mod of H15-124 Was Completed within 7-day Time Frame
05000267/LER-1979-039-03, /03L-0:on 790924,authorized Liquid Waste Release Was Made,Requiring Raising Setpoints on Liquid Waste Activity Monitors Above Normal.Caused by Failure to Return Monitors to Normal Setpoints Prior to Starting Release
05000320/LER-1979-012-03, /03L-0:on 790305,fire Barrier Seals Made of Firewall 50 Cracked,Spalled & Separated While in Mode 1, Making Seals Nonfunctional.Caused by Cracks Developing in Fire Barrier Penetration Seals.Continuous Fire Watch Begun
05000317/LER-1979-020-03, /03L-0 on 790706:while Performing post-mod Test on Rcs,Power Relief Valves RC-402-ERV Failed to Fully Close After Lifting.Cause Not Determined.Pilot Valve Stroke Adjusted & Relief Valve Stroked Satisfactorily
05000318/LER-1979-046-03, /03L-0:on 791214,plant Computer Taken Out of Svc for Corrective Maint,Rendering Incore Detector Sys Inoperable.Caused by Computer Rapid Access Disc Counter Incrementing Improperly,Forcing Computer to Stop
05000271/LER-1979-035-03, /03L-0:on 791215,during Surveillance Testing Msivs,Inboard Valve V2-80A in Main Steam Line a Closed But When Repositioned to Open,Was Found to Be Partially Open.Caused by Spring Plate Binding on Guide Shaft
05000267/LER-1979-052-03, /03L-0:on 791022,at 9% Power B Instrument Air Compressor Found to Have Insufficient Output While a Compressor Out of Svc.Caused by Bent Piston Rod & Worn Valves.Parts Replaced or Rebuilt
05000325/LER-1979-098-01, /01T-0:on 791115,steam Exhaust Check Valve F040 Failed Leak Test.Caused by Sheared Bolt & Nut Lodged in Seat of Reactor Core Isolation Cooling Steam Exhaust Isolation Valve F001.Bolt & Nut Removed.Leak Test Successful
05000325/LER-1979-095-03, /03L-0:on 791106,Units 1 & 2 Chlorine Detectors Failed to Respond to Test Solution.Cause Not Known.Plant Chlorine Source Moved Outside Exclusion Area Until Detectors Repaired
05000267/LER-1979-051-03, /03L-0:on 791017,at 5% Power,Sys 21 Loop 1 Surge Tank Level Decreased to Low Level Setpoint,Tripping Loop 1 Bearing Water Pumps & Making Circulators Inoperable.Caused by Procedural Inadequacy & Operator Error
05000267/LER-1979-055-03, /03L-0:on 791026,during Surveillance Testing,Check Valve V-22370 Was Stuck Open,Making Fire Water Booster Pumps Inoperable for Helium Circulator Drive.Cause Unknown.Valve to Be Opened & Inspected
05000309/LER-1979-027-03, /03L-0:on 791029,leakage Near Safety Injection Tank Discharge Check Valve 1 Exceeded Tech Spec Limits. Caused by O-ring Failure on Bearing Cap of Swing Check valve.O-ring Replaced & Bearing Cap Seal Welded
05000324/LER-1979-087-03, /03L-0:on 791029,containment Valve Would Not Operate During Core Auxiliary Cooling Sys Component Test. Caused by Travel Stops Out of Adjustment.Travel Stops Correctly Set
05000325/LER-1979-096-01, /01T-0:on 791110,nonisolable Weld on Pump a Suction Line Test Connection Discovered Leaking.Cause Unknown.Line Cut,Plugged & Capped.Affected Weld Connections Will Be Metallurgically Evaluated
05000325/LER-1979-085-03, /03L-0:on 791015,core Spray/Rhr Pump Running Annunciator Would Not Reset.Caused by Accumulated Condensate in Switch Resulting in Sticking of Reset Spring Cylinder. Spring Replaced & Conduit Refitted for Tighter End Seal
05000267/LER-1979-047-03, /03L-0:on 791010,prestressed Concrete Realtor Vessel Cooling Water Sys Determined Impaired.Caused by Insufficient Hangar Base Plate & Bolts Out of Concrete.Base Redesigned & Modified to Provide Adequate Strength
05000317/LER-1979-049-03, /03L-0:on 790924,loop Isolation Valve SI-617 Failed to Operate When Motor Operator Received Open Signal. Caused by Contact Misalignment of Movable Contactor. Contactor Realigned & Tested
05000324/LER-1979-084-03, /03L-0:on 790912,1/8-inch Diameter Hole Developed in Nuclear Svc Water Header on Elbow Between 2SW-103-30-157 & 2SW-20-157.Caused by Cement Lining Becoming Detached from Pipe,Allowing Corrosion to Create Hole.Pipe to Be Repl
05000324/LER-1979-081-03, /03L-0:on 790926,both Doors to Reactor Bldg Breezeway Airlock Could Be Opened Simultaneously.Caused by Loose Door Position Solenoids Preventing Interlock Feature from Working.Lock Washers Installed to Ensure Tightness
05000277/LER-1979-043-01, /01T-0:on 790906,two of Four Bolts on Hanger 32-GE-S41 Failed During Insp Program.Caused by Improper Installation of Bolt Anchor Shells.Defective Bolts Have Been Removed & Replaced by Wedge Type Anchor Bolts
05000317/LER-1979-044-03, /03L-0:on 790913,water Leak Discovered Coming from Cracked Weld on Reactor Coolant Charging Pump Discharge Relief Valve Flange.Caused by Pinhole Crack in heat-affected Zone of Socket Weld.Valve Replaced
05000324/LER-1979-075-03, /03L-0:on 790818,during Normal Operator Surveillance of Control Panels,Operator Noticed Low Flow Indicated on 2-CAC-1263.Cause Undetermined.Unit Will Be Monitored
05000267/LER-1979-026-03, /03L-0:on 790807,bearing Water Makeup Pump P-2105 Removed from Svc to Perform Line Repair W/Reactor at 65% Power.Caused by Hole in Recirculation Line of Pump,Requiring Removal from Svc.Line Repaired.Pump Returned to Svc
05000325/LER-1979-059-03, /03L-0:on 790810,during Reactor Startup Discovered Number 7 Superimposed on Number 1 Digit for Position Indication on Rod 14-47.Caused by Problem in Drywell Prototypic Inlet Piping Probe
05000324/LER-1979-064-03, /03L-0 on 790731:GE Notified Util That Error Existed in Tech Specs for Max Critical Power Ratio.Caused by Use of Incorrect Void Coefficient Data.Revision to Tech Specs Currently Underway
05000366/LER-1981-059-03, /03L-0:on 810622,defective Transmitter 2T48-N0101A Discovered in post-accident Torus Water Level Indicator 2T48-R622A During Testing.Caused by Low Fluid Level in Ref Leg Sensing Line.Line Backfilled
05000317/LER-1979-060-03, /03L-0:on 791020,while Performing Load Test of Diesel Generator 12,operator Unable to Achieve Full Load. Caused by High Exhaust Temp on Cylinder 2 & Clogged Injectors.Injectors Overhauled & Adjusted
05000311/LER-1981-039-03, /03L-0:on 810608,determined post-accident Monitoring Instrumentation Had Not Been Completed Since 810422.Caused by Personnel Failure to Enter New Procedure Info Notification Sys.Personnel Counseled
05000348/LER-1981-010-03, /03L-0:on 810318,diesel Generator 1B Declared Inoperable Following Trip on Overspeed During Surveillance Test FNP-1-STP-28.2.Caused by Blown Fuses in Speed Governor. Fuses Replaced
05000267/LER-1980-022-03, /03L-0:on 800424,during 800424-0510,operation W/Total Primary Coolant Oxidants Greater than 10 Ppm & Average Core Outlet Temp Greater than 1,200 Degrees Occurred on Five Occasions.Caused by Reaction of Moisture W/Core
05000267/LER-1979-054-03, /03X-1 on 791029,standby Diesel Engine 1B Tripped on High Cooling Water Temp During Surveillance Test.Caused by Cooling Water Valves Lined Up Incorrectly.Cooling Water Restored & Personnel Instructed in Proper Methods
05000341/LER-1985-039, :on 850716,after Starting HPCI Sys to Perform Startup Test,Oil Leak Developed at Operator of Turbine Stop Valve.Caused by Loose Flange Between Pilot Valve Assembly & Valve Operator.Flange Bolts Tightened
05000334/LER-1983-023-03, /03L-0:on 830910,during Performance of Bvt 1.1-1.47.4 & 1.3-1.47.5 Discovered Valves & Flanges W/ Unacceptable Leakage.Caused by Inability to Hold Applied Pressure.Valves/Flanges Replaced
05000346/LER-1983-047-03, /03L-0:on 830831,during Independent Offsite Ac Source Bus Transfer Procedure,Automatic Unit Power Supply to Each 345 Kv Transmission Line Failed.Caused by Dirt in Source Selector Switch
05000306/LER-1983-020-03, /03L-0:on 830829,maint Air Lock Door Exhibited Leakage of 21,000 Sccm Exceeding Tech Spec Limit.Caused by Deterioration of Grafoil Packing at Inboard Shaft Seals. Packing Will Be Replaced Prior to Startup
05000324/LER-1983-070-03, /03L-0:on 830907,core Spray or RHR Pumps Running Annunciation Received W/No Abnormalities or Pumps Running. Caused by Microswitch NO20A Failure.Switch Replaced
05000366/LER-1983-039-03, /03L-0:on 830614,Procedure HNP-2-3901 Re Relief Valve Operability Discovered Erroneously Revised.Caused by Personnel Error.Procedure re-revised
05000237/LER-1983-082-03, /03L-0:on 831225,while Performing Weekly & Daily Turbine Checks During Normal Operation,Control Valve 4 Failed to Give half-scram When Tested.Probably Caused by Failed Test Switch CVTS-4.Recorder Installed
05000373/LER-1982-156-03, /03L-0:on 821119,while Performing STP-23A,reactor Coolant Conductivity Exceeded Limit.Caused by Personnel Error.Personnel Advised That Startup Test Insufficient Reason to Bypass Condensate Polishers
05000321/LER-1983-099-03, /03L-0:on 830901,drywell Torus Recorder Indicated Downscale & Declared Inoperable Due to Lack of Power.Caused by Personnel Error.Power Restored by Closing Power Link
05000366/LER-1983-073-03, /03L-0:on 830802,during Performance of HPCI Turbine Exhaust Diaphragm Pressure Instrument Procedure Ft&C,B HPCI Instrument Out of Calibr.Caused by Setpoint Drift.Instrument Recalibr
05000321/LER-1983-085-03, /03L-0:on 830802,drywell Equipment Drain Sump Isolation Valve 1G11-F020 Had Double Position Indication in Full Closed Position.Caused by Loose Set Screw in Valve Closed Limit Switch Actuator.Actuator Adjusted
05000366/LER-1983-066-01, /01T-0:on 830727,while Investigating Problems W/Pressure transmitters,12 Open Links Discovered in MSIV Leakage Control Sys 2E32.Caused by Personnel Error.Links Closed
05000366/LER-1983-026-03, /03L-0:on 830610,diesel Generator 2C Failed to auto-start After Manual Trip.Caused by Shutdown Solenoid Stuck in Shutdown Position.Solenoid Cleaned
05000267/LER-1983-014-03, /03L-0:on 830309,emergency Set 1B Emergency Diesel 1D Tripped Due to Dc Electrical Sys Intermittent Ground. Caused by Loose Conduit Termination Lock Nut.Nut Tightened & Secured
05000333/LER-1983-020-03, /03L-0:on 830520,during Monthly Valve Cycling Surveillance Test of 23 MO-60 (HPCI Outboard Containment Isolation Bypass Valve),Valve Motor Tripped on Overload. Caused by Hard Valve Packing
05000334/LER-1983-017-03, /03L-0:on 830528,following Reactor Trip,One Source Range Nuclear Detector Observed Not Indicating & Other Source Range Began Spiking High.Both Declared Inoperable. Cause Not Determined.Both Detectors Replaced
05000325/LER-1983-007-03, During Extended Refueling Outage,One Fuel Bundle Located Around Control Rods 22-15, 34-23,34-27 & 26-43.Caused by Procedual Inadequacy.Rods Inserted & Procedure Revised
05000334/LER-1982-004-03, /03L-0:on 820127,backup RHR Pump Lost out-of-svc When Normal Ac Power Source Lost Due to Fault in Section of 4 Kv Bus Cable.Cause for Cable Fault Unknown.Cable Returned to Vendor for Analysis
05000254/LER-1983-006-03, /03L-0:on 830213,during Monthly Surveillance Test on Condenser Pit 5-ft Trip Circuits,Level Switch 1-4441-25B Failed to Give Circulating Water Pump Trip Signal.Caused by Broken Wire in Switch Mechanism.Switch Replaced
05000267/LER-1983-018-03, /03L-0:on 830517,w/reactor Shutdown,All Outside Power Lost Due to High Winds & Snow.Emergency Diesel Generator Load Shedding & Sequencing Relays Failed to Operate.Caused by Coil Failures.Relays Tested
05000366/LER-1983-038-03, /03L-0:on 830605,reactor Bldg Exhaust Vent Radiation Monitor D (2D11-K609D) Failed Upscale.Caused by Sensor & Converter Unit (2D11-N010D) Failing Electronically. Unit Replaced & Calibr W/Monitor
05000416/LER-1983-056-03, /03L-0:on 830318,standby Fresh Air Fan Failed During Planned Maint Activity.Caused by Faulty Relay.Relay Replaced & Functionally Tested.Investigation of Relay Failure Continuing.Update Rept Will Be Submitted by 830615
05000346/LER-1982-050-03, /03L-0:on 820921,breaker BE106 Opened,Causing MCCE12A to de-energize.Caused by Momentary Ground Due to Failure of Essential Pressurizer Heater (UB3-2).Maint Work Order 82-2433 Issued
05000265/LER-1982-017-03, /03L-0:on 821001,small Leak Discovered in HPCI Sys Supply Steam Line Break Flange.Caused by Failed Flange Gasket.Gasket Replaced like-for-like During & Prior to Outage.Leakage Stopped W/Flange Bolt Adjustments
05000366/LER-1982-116-03, /03L-0:on 821014,during Full Load Operation, Drywell Hydrogen & Oxygen Analyzer B Found Inoperative. Caused by Failure of Diaphragm Capscrew on Sample Pump Connecting Rod.Capscrew Replaced & Analyzer Recalibr
05000311/LER-1982-107-03, /03L-0:on 820923,axial Flux Distribution Went Out of Target Band Due to Turbine Load Reduction When Turbine Generator Stator Water Temp Increased.Temp Increase Caused by Clogged Ports on Valve Positioner 2ST1
05000334/LER-1983-006-03, /03L-0:on 830212,trip Valve (TV-MS-101B) Failed to Close During Stroke Test.Caused by Combination of Debris That Caused Slight Cylinder Scoring & Loose Pivot Arm.Piston Dressed Up & Cylinder Wall Honed
05000334/LER-1982-047-03, /03L-0:on 821013,pressurizer Level Channel I Indicator LI-RC-459 Recorded to Be Out of 4% Tolerance Band. Caused by Leaking Instrument Valve Resulting in Loss of Level in Ref Leg of LT-RC-459.Valve Internals Replaced
05000334/LER-1982-038-03, /03L-0:on 820925,during Attempt to Secure Turbine Driven Auxiliary Feed pump,TV-MS-105B Failed to Close.Caused by Nut Lodging in TV-MS-105B Valve Body Due to Failed Check Valve MS-20.Nut Removed
05000366/LER-1983-111-03, /03L-0:on 831010,while Reviewing Procedure HNP-1- 1061, Daily Outside Rounds, Low Flow & Pressure Readings Noted on Plant Svc Water Pump 2P41-C001A.Pump 2A Shut Down. Caused by Worn Out Pump.Pump 2A Repaired
05000206/LER-1982-014-03, /03L-0:on 820429,four Snubbers Identified as Having Empty Reservoirs.Upon Further Testing,One Snubber Failed to Pass Stroke Test.Caused by Excessive Hydraulic Fluid Leakage.Snubbers Rebuilt
05000334/LER-1983-026-03, /03L-0:on 830919,while Filling Safety Injection Accumulator 1A,accumulator Low Level Alarms & Containment Sump Alarm Received in Control Room.Reducer Did Not Provide Proper Drawback.Reducer Repaired