Semantic search
Jump to navigation
Jump to search
| Issue date | Title | Topic | |
|---|---|---|---|
| ML20029E512 | 12 May 1994 | LER 93-008-01:on 930706,high Pressure Injection Suction Valve Determined to Be Inoperable.Caused by Lack of Engineering Review for Motor Brake Voltage Requirements. Valves Locked & Brake removed.W/940512 Ltr | |
| ML20029D767 | 3 May 1994 | LER 94-002-00:on 940404,performance of Surveillance Check Power Distibution Breaker Alignment & Power Availability Verification Resulted in Entry Into LCO 3.0.3.Caused by Procedure Error.Procedures revised.W/940503 Ltr | |
| ML20046C558 | 4 August 1993 | LER 93-008-00:on 930706,possibility of MOV W/Brakes Failing to Perform Safety Function Under Degraded Voltage Conditions Due to Lack of Engineering Review.Identified & Reviewed MOV W/Motor Brakes for Safety significance.W/930804 Ltr | |
| ML20046B412 | 28 July 1993 | LER 93-007-00:on 930628,noticed That Hydrogen Pressure Setpoint Found to Be Set Above 10 Psig.Caused by Personnel Error.Mod Design Package Developed to Raise Pressure Regulator setpoint.W/930728 Ltr | |
| ML20045F774 | 30 June 1993 | LER 93-001-01:on 930305,cooldown Exceeding Limits of TS 3.4.9.1 Experienced After Switching from SG Cooling to Dh Sys Cooling.Caused by Failure of Cv Controller.Valve Repaired & Valve Operation Instructions Revised | |
| ML20045D774 | 18 June 1993 | LER 93-006-00:on 930520,inadequately Secured Separation Barrier Identified That Could Affect Control Switches for safety-related Equipment on Main Control Board.Caused by Human Error.Placard Posted to Restrict area.W/930618 Ltr | |
| ML20045B438 | 10 June 1993 | LER 93-005-00:on 930518,notified That Control Circuit for Makeup & Purification Sys Letdown Isolation Valve Did Not Meet Electrical Isolation Criteria Due to Human Error.Mod in Development Will Be expanded.W/930610 Ltr | |
| ML20044D210 | 10 May 1993 | LER 93-004-00:on 930408,inappropriate Personnel Action Resulted in Degraded Class 1E Bus Voltage & Actuation of Edg.Licensee Established Addl Administrative Controls on Switchyard activities.W/930510 Ltr | |
| ML20044D165 | 10 May 1993 | LER 93-003-00:on 930408,determined That Insufficient Instrument Error Considered When Operating Limits for Core Flood Tank Selected.Caused by Programmatic Deficiency.Alarm Bistables Reset & Allowed Margin expanded.W/930510 Ltr | |
| ML20024H200 | 20 May 1991 | LER 91-003-00:on 910420,emergency Feedwater Actuation & Manual Reactor Trip Occurred.Caused by Water Instrusion Into Pump Loss of Circulating Water Pump.Plant Modification Previously initiated.W/910520 Ltr | |
| ML20024H174 | 17 May 1991 | LER 90-002-02:on 900216,determined That Fire Dampers May Not Be Operable Under Expected Ventilation Flow Conditions Due to Design Error.Design Basis Documents updated.W/910517 Ltr | Safe Shutdown Fire Barrier Continuous fire watch Fire Watch Hourly Fire Watch |
| ML20029B075 | 28 February 1991 | LER 91-002-00:on 910129,startup Transformer Incapable of Maintaining Voltage Output Above Setpoint of Second Level Undervoltage Relays Under Es Actuation Conditions.New Offsite Power Supply installed.W/910228 Ltr | |
| ML20029A653 | 25 February 1991 | LER 91-001-00:on 910124,engineered Safeguards Train a HPI Recirculation Isolation Valve MUV-53 Declared Inoperable Due to Undersized Thermal Overload Elements for Motor Operator.Cause Undetermined.Elements replaced.W/910225 Ltr | |
| ML20028H713 | 21 January 1991 | LER 89-022-01:on 890614,erroneous Indication of Loss of Main Feedwater Pumps Occurred Resulting in Manual ESF Actuation. Temporary Loss of Supervisory Indicating Lights Expected During Bus Realignment.Procedures revised.W/910121 Ltr | Manual Operator Action |
| ML20043H575 | 22 June 1990 | LER 90-009-00:on 900523,discovered That Paperwork for Mod to Replace Feedwater Vent Valve Still Open 12 Months After Work Completed.Caused by Lost Blanket Work Request Re post-maint Testing.New Work Request initiated.W/900622 Ltr | Hydrostatic |
| ML20043G651 | 14 June 1990 | LER 90-008-00:on 900514,determined That Fault Current Could Develop Across Engineered Safeguards 480-volt Bus Output Breakers.Caused by Failure to Perform Adequate Short Circuit Analysis.Deficient Trip Devices replaced.W/900614 Ltr | |
| ML20043C522 | 31 May 1990 | LER 89-035-01:on 890906,determined That Dc Powered Components Exhibited Discrepancy in Rated Voltages & Actual Voltages.Caused by Inadequate Control of Design Process.Inoperable Components replaced.W/900531 Ltr | |
| ML20043B809 | 23 May 1990 | LER 90-007-00:on 900112,discovered That Door Between Control Room Complex & Turbine Bldg Removed for Mod Work,Resulting in Inoperability of Both Trains of Emergency Ventilation Sys.Door Replaced & Warning Signs affixed.W/900523 Ltr | |
| ML20042G764 | 9 May 1990 | LER 90-006-00:on 900410,reevaluation of Design Calculations Discovered Deficient Valve Operator Installation.Sufficient Thrust Not Developed to Open or Close Valves Due to Undersized Spring Packs.Spring Packs ordered.W/900509 Ltr | |
| ML20042F978 | 7 May 1990 | LER 89-031-01:on 890828,480-volt Engineered Safeguards Stepdown Transformer a Faulted Causing Decay Heat Train Closed Cycle Cooling Pump a to Deenergize.Caused by Degraded Insulation.Transformer replaced.W/900507 Ltr | Safe Shutdown Shutdown Margin Emergency Lighting Fatality |
| ML20012D809 | 22 March 1990 | LER 90-003-00:on 900220,instrument Fluctuation Noted During Surveillance of Chilled Water Pump.Caused by Location of Flow Element within Chilled Water Sys.Relief Request Submitted & Field Problem Rept generated.W/900322 Ltr | |
| ML20012D028 | 19 March 1990 | LER 90-002-00:on 900216,determined That Fire Dampers May Not Be Operable Under Expected Ventilation Flow Conditions Due to Design Error.Caused by Failure of Original Design Criteria to Address Need.Documentation updated.W/900319 Ltr | Safe Shutdown Fire Barrier Continuous fire watch Fire Watch Hourly Fire Watch |
| ML20011F173 | 21 February 1990 | LER 90-001-00:on 900221,RCS Leakage Calculations Indicated That Unidentified Leakage Exceeded Tech Spec Limits.Caused by Failed Packing on Block Valve.Valve Repacked During Feb 1990 Maint outage.W/900221 Ltr | Unidentified leakage |
| ML19354D909 | 17 January 1990 | LER 89-016-03:on 890426,administrative Problems Caused Deficiencies in Environ Qualification Program That Resulted in Plant Equipment Not Being Properly Qualified.Effort to Correct Environ Qualification Deficiencies Underway | |
| ML20006E394 | 8 January 1990 | LER 89-041-00:on 891208,partial,simultaneous Withdrawal of Two Control Rod Safety Groups Occurred & Safety Group 3 Control Transferred to Auxiliary Power Supply.Cause Undetermined.Select Relays replaced.W/900207 Ltr | |
| ML20005F160 | 8 January 1990 | LER 89-040-00:on 891208,emergency Diesel Generators a & B Actuated Due to Degraded Voltage When Condensate Pump Started.Operator Guidelines & Procedures for Starting Condensate Pumps Being revised.W/900108 Ltr | |
| ML20011D840 | 22 December 1989 | LER 89-030-01:on 890824,determined That Pump Discharge Pressure & Flow Less than Required.On 890826,plant Entered Hot Standby.Caused by Installation of Incorrect Impeller in Pump.Original Impeller Reinstalled Upon repair.W/891222 Ltr | Ultimate heat sink |
| ML20011D228 | 15 December 1989 | LER 89-026-01:on 890629,emergency Diesel Generator 1B Failed post-maint Test & Could Not Be Returned to Svc within Time Allowed by Tech Specs.Caused by Rotor Not Turning.Crankcase Vapor Ejector cleaned.W/891215 Ltr | |
| ML19332E769 | 7 December 1989 | LER 89-039-00:on 891107,determined That Control Circuits for Two Makeup Valves Did Not Meet Separation Criteria of 10CFR50 App R.Caused by Cognitive Personnel Error.Roving Fire Watch Patrol Confirmed in effect.W/891207 Ltr | Safe Shutdown Fire Watch |
| ML19332F017 | 30 November 1989 | LER 89-038-00:on 891029,util Engineers Discovered That Administrative Controls Not in Place for Three Makeup & Purification Sys Valves.Caused by Personnel Error.Plant Procedures revised.W/891130 Ltr | Safe Shutdown |
| ML19332D139 | 27 November 1989 | LER 89-037-00:on 891026,determined That Instrumentation Used to Balance HPI Flow Through Four Injection Lines During Small Break LOCA Inadequate.Caused by Inadequate Review of B&W Guidelines.Flow Instrument installed.W/891127 Ltr | Time of Discovery |
| ML19327C261 | 17 November 1989 | LER 89-036-00:on 891018,determined That Plant Operating Outside Design Basis Since Borated Water Storage Tank Level Transmitters Not Seismically Qualified.Caused by Personnel Error.Unqualified Transmitters replaced.W/891117 Ltr | Earthquake |
| ML19325F337 | 10 November 1989 | LER 89-033-00:on 890908,second Level Undervoltage Relay Sys Setpoint for Engineered Safeguards Buses Not Conservative & Led to Operation Outside Plant Design Basis.Caused by Personnel Error.Setpoint changed.W/891110 Ltr | |
| ML19325F334 | 10 November 1989 | LER 89-035-00:on 890906,discrepancy Noted in dc-powered Component Rated Voltages & Actual Voltages Seen by Components.Caused by Inadequate Control of Design Process. All Components Replaced Prior to startup.W/891110 Ltr | |
| ML19325E737 | 27 October 1989 | LER 85-034-01:on 850310,valve Alarm Function for Core Flood Tank Isolation Valves Failed to Meet Acceptance Criteria.On 850809,unit Entered Mode 3 & Then Raised RCS Pressure Above 750 Psig W/O Meeting Operability surveillances.W/891027 Ltr | |
| ML19324B392 | 26 October 1989 | LER 88-002-02:on 880107,emergency Feedwater Actuation Occurred on Loss of Both Main Feedwater Pumps.Caused by Instrumentation & Control Technician Error.Idle Feedwater Pump Started & Actuation reset.W/891026 Ltr | Overspeed trip |
| ML19324B387 | 26 October 1989 | LER 89-034-00:on 890926,two Conditions Determined to Be Outside Plant Design Basis Re Solenoid Control Valves.Caused by Cognitive Personnel Error.Test Solenoid Valve Circuits Provided W/Isolation fuses.W/891026 Ltr | |
| ML19327B230 | 23 October 1989 | LER 89-016-02:from 890227-0601,deficiencies Re Environ Qualification of Plant Equipment Discovered.Caused by Deficiencies in Detailed Development & Implementation of Environ Qualification Program.Program reviewed.W/891023 Ltr | |
| ML20024D250 | 26 July 1983 | Updated LER 83-019/03L-1:on 830406,breaker in Engineered Safeguards Motor Control Ctr 3B1 Shorted Out,Causing Various Pieces of Equipment on Train B to Be Inoperable.Caused by Personnel Error.Breaker Removed & cleaned.W/830726 Ltr | Boric Acid Fire Watch |
| ML20024D149 | 26 July 1983 | Updated LER 82-003/01T-0:on 820128,RCS Leakage Calculations Showed Unidentified Leakage at Rate Greater than 1 Gpm. Caused by Thermally Induced Cyclic Failure.New Valve Will Be Installed in Improved location.W/830726 Ltr | Pressure boundary leak |
| ML20024D106 | 26 July 1983 | Updated LER 82-004/01T-1:on 820129,while Performing Visual Insp of Reactor Coolant Pump a Seal Package,Rcpb Leakage Discovered from Crack in Seal Weld.Caused by Installation Error.Seal Replaced & Procedures revised.W/830726 Ltr | Time of Discovery Pressure Boundary Leakage |
| ML20024C095 | 27 June 1983 | LER 83-023/01T-0:on 830613,fire Damper FD-86,in Duct Work Between Auxiliary Bldg & Control Complex,Discovered Missing. Cause Unknown.Continuous Fire Watch Established.Evaluation underway.W/830627 Ltr | Fire Barrier Continuous fire watch |
| ML20023E097 | 1 June 1983 | LER 83-021/03L-0:on 830504,three Hydraulic Snubbers Failed Functional Test During Dec Outage & 107 Snubbers Failed Test During Refuel Iv.Caused by Seal Failure & Valve Assembly Contamination.All Snubbers modified.W/830531 Ltr | |
| ML20023C525 | 9 May 1983 | LER 83-020/03L-0:on 830409,discovered That Surveillance Interval for Fire Detection Instrumentation in Emergency Diesel Generator & Control Rooms Exceeded by 6 Months.Caused by Procedural Inadequacy.Procedure SP-411 Will Be Revised | |
| ML20023B409 | 27 April 1983 | LER 83-018/01T-0:on 830413,preliminary Repts Received from B&W Indicating That 51 of 120 Upper Core Barrel Bolts Ultrasonically Tested May Be Defective.Cause Unknown. Investigation Underway.Supplemental Rept Will Be Written | |
| ML20028E056 | 13 January 1983 | LER 82-075/03L-0:on 821215,during Cold Shutdown,Circuit Breaker on Control Complex Ventilation Radiation Monitor RMA-5 Tripped.Caused by Broken Pump Vane Binding Pump. Pump Replaced | |
| ML20028A532 | 10 November 1982 | LER 82-063/03L-0:on 821011,reactor Bldg Average Air Temp Exceeded 130 F Limit.Caused by Strain on Instrument Air Line Causing Line to Split.Line Replaced on 821011 | |
| ML20027D702 | 29 October 1982 | LER 82-061/03L-0:on 820929,fan Damper Operator on Industrial Cooler Failed,Resulting in Reactor Bldg Average Air Temp Exceeding 130 F.Caused by Water in Instrument Air Sys Due to Personnel Failing to Close Valve FSV-250.Dampers Wired Open | |
| ML20027B888 | 24 September 1982 | LER 82-055/03L-0:on 820825,feedwater Ultrasonic Flow Indicator FW-313-FI Found Inoperable.Caused by Instrument Failure Due to High Ambient Temp at Instrument Cabinet Location.Instrument Repaired.Flow Transmitters Replaced | |
| ML20027B900 | 24 September 1982 | LER 82-056/03L-0:on 820827,during Normal Operation,Primary Containment Average Air Temp Exceeded 130 F Tech Spec Limit. Caused by Failure of Pneumatic Control Line for Industrial Coolers.Control Line Replaced & Coolers Returned to Svc |