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Category:LICENSEE EVENT REPORT (SEE ALSO AO
MONTHYEARML20046A4871993-07-23023 July 1993 LER 93-001-00:on 930607,determined RCP Uv & Underfrequency Portion of Rt Sys,& TDAFP Autostart Signal from RCP Bus Uv Contained Design Deviation Due to Personnel Error. Procedural Guidance enhanced.W/930723 Ltr ML20044D1331993-05-11011 May 1993 LER 91-007-01:on 910629,two Neutral Overcurrent Relays on Unit 1B Auxiliary Transformer Actuated,Resulting in Generator Trip & Reactor Trip.Caused by Electrical Fault. Loose Strand Removed from conductor.W/930511 Ltr ML20024G7191991-04-23023 April 1991 LER 91-001-00:on 910401,reactor Trip Occurred When Rod Dropped in Core.Caused by Defective Circuit Card in Rod Control Sys.Suspect Circuit Cards Replaced & Sent to Westinghouse for evaluation.W/910423 Ltr ML20043F1681990-06-0808 June 1990 LER 90-001-00:on 900512,reactor Tripped Due to lo-lo Water Level in Steam Generator 2A.Caused by Procedural Inadequacy. Procedure FNP-2-STP-151 Revised to Provide Addl Initial Conditions to Prevent Subj event.W/900608 Ltr ML20012D9591990-03-20020 March 1990 LER 90-002-00:on 900222,two Cases Found Where Surveillance Testing Procedures Did Not Perform All Tests Required by Tech Specs.Caused by Inadequate Procedural Guidance. Procedures revised.W/900320 Ltr ML20012C3031990-03-13013 March 1990 LER 90-001-00:on 900213,fire Watch Not Established within Required Time Period Due to Personnel Error.Administrative Procedure FNP-0-SOP-0.4 Revised & Personnel Retrained on requirements.W/900313 Ltr ML20012B4851990-03-0606 March 1990 LER 83-039/03X-2:on 830726,discovered That Handwheel for Inner Door of Personnel Airlock in Shut Position & Partially Opened.Caused by Excessive Use of Door During Outages.Door Repaired & Returned to Operable status.W/900306 Ltr ML19354E3341990-01-23023 January 1990 LER 89-016-00:on 891228,discovered That Required Surveillance for Plant Vent Stack Radioactive Gas Monitor Not Performed.Caused by Personnel Improperly Scheduling Surveillance for Time Later than Due date.W/900123 Ltr ML20011D5611989-12-18018 December 1989 LER 89-015-00:on 891118,reactor Tripped Due to Turbine Trip. Caused by Voltage Transient in Power Circuit to Digital electro-hydraulic Control Sys & Inverter Failure.Inverter Repaired & Returned to svc.W/891218 Ltr ML19332F9061989-12-13013 December 1989 LER 89-008-00:on 891113,containment Integrity Not Maintained for Approx 30 S.Caused by Personnel in That Inner Door Was Left Blocked Open.Personnel Counseled & Interim Administrative Controls established.W/891213 Ltr ML19332F6761989-12-12012 December 1989 LER 89-007-00:on 891112,both Motor Driven Auxiliary Feedwater Pumps Failed to Start Manually by Operator.Caused by Cognitive Personnel Error Re Design Change.Wiring Discrepancy Corrected & Pump Returned to svc.W/891212 Ltr ML19351A4571989-12-12012 December 1989 LER 89-014-00:from 891115-16,Tech Spec 3.0.3 Entered Voluntarily to Repair Leaking Containment Purge Isolation Dampers.Caused by Need to Repair Dampers.Dampers Closed & Automatic Isolation Feature restored.W/891212 Ltr ML19332F0851989-12-0707 December 1989 LER 89-006-00:on 891112,safety Injection & Reactor Trip Initiated Due to Low Steam Line Pressure.Caused by Personnel Error Involving Misconfiguration of Circuit Valve.Personnel Involved counseled.W/891207 Ltr ML19327C2621989-11-14014 November 1989 LER 89-012-00:on 891018,reactor Tripped Due to lo-lo Steam Generator Level Due to Closure of Governor Valves.Caused by Design Error in Digital electro-hydraulic Control Sys.Valve Position Limiter Feature removed.W/891114 Ltr ML19327C2671989-11-14014 November 1989 LER 89-013-00:on 891019,reactor Tripped Due to lo-lo Level in Steam Generator 2C.Caused by Operator Incorrectly Transferring Steam Generator Level Control to Main Feedwater.Involved Personnel counseled.W/891114 Ltr ML19354D4691989-11-0101 November 1989 LER 89-005-00:on 890930 & 1001,core Alterations Performed W/O Establishing Containment Refueling Integrity.Caused by Cognitive Personnel Error.Personnel Involved in Event Counseled.Containment Procedure strengthened.W/891101 Ltr ML19327B5451989-10-25025 October 1989 LER 89-011-00:on 890925,discovered That Tech Spec 4.6.3.1.a Surveillance Requirement Re Containment Air Lock Outer Door Not Done.Caused by Personnel Error.Individuals Involved Counseled Re Importance of Subj requirements.W/891025 Ltr ML19325D4941989-10-17017 October 1989 LER 89-004-00:on 890616,determined That Calculations Were Not Available to Demonstrate That Svc Water Sys Capable of Supplying Design Flow to safety-related Loads Under Scenario of Seismic event.W/891017 Ltr ML19325D2461989-10-12012 October 1989 LER 89-010-00:on 890920,reactor Tripped Manually Following Loss of Operating Steam Generator Feed Pump.Caused by Inadvertent Opening of Overspeed Trip Test Valve.Individual Involved in Event Counseled to Be More aware.W/891012 Ltr ML19325C7481989-10-10010 October 1989 LER 89-009-00:on 890525,determined That Power Range Nuclear Instrumentation Channels Reading Approx 7% Low.Equalizing Valves on Two of Three Instruments Were Leaking.Valves Repaired & Power Range Instruments adjusted.W/891010 Ltr ML20024F6841983-08-31031 August 1983 LER 83-031/03L-0:on 830806,during Testing,Instrumentation Channel Associated W/Level Transmitter LT-474 Declared Inoperable.Caused by Setpoint Drift of Comparator Card.Card Adjusted & Instrumentation Channel Declared Operable ML20024F6781983-08-31031 August 1983 LER 83-042/03L-0:on 830802,post-LOCA Hydrogen Recombiner 1A Declared Inoperable.Caused by Failure of Temp Indicator.New Indicator Installed & Declared Operable ML20024D0871983-07-26026 July 1983 LER 83-038/03L-0:on 830627,during Turbine Driven Auxiliary Feedwater Pump Inservice Test,Pump Failed to Start from Train a Steam Supply & Declared Inoperable.Caused by Valve HV-3226 Failing to Stroke properly.W/830726 Ltr ML20024C1251983-06-30030 June 1983 LER 83-027/03L-0:on 830607,during Performance of FNP-1-STP-43.0,train a Penetration Room Filtration Sys Declared Inoperable When Exhaust Fan Damper 3357A Would Not Open.Caused by Comparator Card failure.W/830630 Ltr ML20024C4011983-06-22022 June 1983 LER 83-025/03L-0:on 830528,during Calibr Procedure FNP-2-STP-612.0,reactor Coolant Pump 2A Undervoltage Relay 27-3 Declared Inoperable.Caused by Setpoint Drift.Relay Setpoint Adjusted ML20024C4061983-06-22022 June 1983 LER 83-024/03L-0:on 830525,following Increased Count Rate on Containment Atmosphere Particulate Monitoring Sys R-11, RCS Unidentified Leakage Found Above Tech Specs.Cause Not Stated.Loop B Drain Valve Tightened ML20023B5821983-04-29029 April 1983 LER 83-014/03L-0:on 830330,during Surveillance Test of Main Feedwater Pump Turbine 1A,RCS Tavg Decreased Below 541 F. Caused by Overfeeding of Steam Generators Due to Excessive Leak Past Main Feedwater Pump Discharge Valve ML20023B5281983-04-27027 April 1983 LER 83-015/03L-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 ML20023B5321983-04-27027 April 1983 LER 83-012/03L-0:on 830402,overtemp-delta Temp Loop 2 Channel II Declared Inoperable When Bistables 422C1-2 Tripped.Caused by Power Supply Failure of Comparator Card. Card Replaced & Loop Calibr ML20028G3051983-01-28028 January 1983 LER 82-062/03L-0:on 821231,noble Gas Activity Monitor R15 Declared Inoperable.Caused by Blown Fuse.Fuse Replaced & Monitor Returned to Svc ML20028G3111983-01-28028 January 1983 LER 83-001/03L-0:on 830102,RCS Subcooling Monitor Channel 2 Declared Inoperable Following Receipt of Main Control Board Alarms.Caused by Faulty Printed Circuit Card.Connector Pins on Card Cleaned ML20028G3091983-01-28028 January 1983 LER 82-063/03L-0:on 821230,B Train Chlorine Detector Declared Inoperable When Control Room Supply Damper Would Not Close.Caused by Faulty Solenoid Valve.Valve Replaced ML20027D9171982-11-0505 November 1982 LER 82-042/03L-0:on 821013,containment Auxiliary Personnel Hatch Failed to Meet Outer Door Acceptance Criteria.Caused by Worn Gaskets.Gaskets Replaced ML20027D3451982-10-26026 October 1982 LER 82-056/03L-0:on 820927,control Rod Bank D Declared Inoperable When Rods Would Not Move in Manual Control.Caused by Bank Select Relay Sticking,Causing Control Banks B & D to Be Selected Simultaneously.Relay Inspected & Reinstalled ML20027B7491982-09-21021 September 1982 LER 82-038/03L-0:on 820823,inboard & Outboard Pumps of Containment Atmosphere Monitors R-11 (Particulate Monitor) & R-12 (Gaseous Monitor) Declared Inoperable.Caused by Defective Relay & High Flow Switch.Relay & Switch Replaced ML20027B7471982-09-21021 September 1982 LER 82-036/03L-0:on 820824,2B Auxiliary Feedwater Pump Dc Control Power Breaker Inadvertently Opened.Caused by Personnel Error.Breaker Immediately Reclosed & Personnel Counseled ML20027B7461982-09-21021 September 1982 LER 82-051/03L-0:on 820823,1B Control Room Air Conditioner Failed,Rendering B Train Control Room Emergency Air Cleanup Sys Inoperable.Caused by Failed Fan Drive Belts.Belts Replaced & Sys Returned to Svc ML20027B7451982-09-21021 September 1982 LER 82-049/03L-0:on 820822,diesel Generator 1-2A Inadvertently Rendered Inoperable.Caused by Unauthorized Replacement of Lube Oil Strainers & Personnel Error. Generator Returned to Svc ML20052H6541982-04-30030 April 1982 LER 82-015/03L-0:on 820408,radiation Monitor 25A (Spent Fuel Storage Pool Area Gaseous activity-ventilation Sys Isolation) Declared Inoperable While Performing Test.Caused by Dirty Contacts on Mod Selector Switch.Contacts Cleaned ML20052H6591982-04-30030 April 1982 LER 82-017/03L-0:on 820413,FI-497 (Steam Generator 1C Feedwater Flow) Instrumentation Channel Declared Inoperable When Max Allowable Channel Check Error Was Exceeded.Caused by Faulty Transmitter Amplifier Card.Card Replaced ML20052C1391982-04-22022 April 1982 LER 82-014/03L-0:on 820326,28 & 0408,B Train Chlorine Detector Declared Inoperable Due to Detector Tape Not Advancing.Caused by Movement Indicator Binding Detector Tape & Sheared Pin in Tape Drive Mechanism ML20052C1371982-04-22022 April 1982 LER 82-014/03L-0:on 820328,while Performing Calibr & Functional Test,T average-low-low B Instrumentation Loop Declared Inoperable Due to Indicator Reading.Caused by Setpoint Drift.Power Supply Card Replaced ML20052C1401982-04-22022 April 1982 LER 82-015/03L-0:on 820325,radiation Monitor R29B Instrumentation Channel Declared Inoperable When Displays on All Readout Consoles Were Inaccurate.Caused by Dirty Contacts & Faulty Link.Contacts Cleaned ML20052C1351982-04-22022 April 1982 LER 82-012/03L-0:on 820326,during Routine Insp,Turbine Driven Auxiliary Feedwater Pump Declared Inoperable When Outboard Bearing Oil Bubbler Found Broken & Oil Drained. Possibly Caused by Workers Handling Scaffolding in Area ML20052A6571982-04-16016 April 1982 LER 82-013/03L-0:on 820317,containment Atmosphere Activity Monitors R-11 (Particulate Monitor) & R-12 (Gaseous Monitor) Declared Inoperable Due to Failure of Vacuum Pump.Caused by Failed Outboard Pump.Filter & Gasket Replaced ML20052A6671982-03-25025 March 1982 LER 82-009/03L-0:on 820228,instrumentation Loop Associated w/FT-474 (Steam Generator a Flow Transmitter) Declared Inoperable.Caused by Leaking Equalizing Valve.Valve Stem Repaired ML20052A6611982-03-25025 March 1982 LER 82-005/03L-0:on 820226,4160-volt B Train Ac Electrical Power Circuit Declared Inoperable When Emergency Bus 2G de-energized.Bus 2G de-energized When Breaker 2-DG15 Opened. Cause Under Investigation ML20052A6711982-03-25025 March 1982 LER 82-010/03L-0:on 820226,instrumentation Loop Associated w/LI-474 (Steam Generator a Level Indicator) Declared Inoperable.Caused by Loss of Necessary Level in Ref Leg While Steam Generator Not in Svc.Leg Refilled ML20052A6631982-03-25025 March 1982 LER 82-008/03L-0:on 820226,instrumentation Loop Associated w/LI-485 (Steam Generator B Level Indication) Declared Inoperable When Reading Was Out of Tolerance W/Other Channels.Caused by Obstruction in Ref Leg ML20050C1861982-03-19019 March 1982 LER 82-006/01T-0:on 820310,levels in Fire Protection Tanks a & B Fell to Approx 85,000 Gallons Each as Result of Inadvertent Actuation of Fire Protection Deluge Sys on Cooling Tower 1A.Caused by Personnel Error 1993-07-23
[Table view] Category:RO)
MONTHYEARML20046A4871993-07-23023 July 1993 LER 93-001-00:on 930607,determined RCP Uv & Underfrequency Portion of Rt Sys,& TDAFP Autostart Signal from RCP Bus Uv Contained Design Deviation Due to Personnel Error. Procedural Guidance enhanced.W/930723 Ltr ML20044D1331993-05-11011 May 1993 LER 91-007-01:on 910629,two Neutral Overcurrent Relays on Unit 1B Auxiliary Transformer Actuated,Resulting in Generator Trip & Reactor Trip.Caused by Electrical Fault. Loose Strand Removed from conductor.W/930511 Ltr ML20024G7191991-04-23023 April 1991 LER 91-001-00:on 910401,reactor Trip Occurred When Rod Dropped in Core.Caused by Defective Circuit Card in Rod Control Sys.Suspect Circuit Cards Replaced & Sent to Westinghouse for evaluation.W/910423 Ltr ML20043F1681990-06-0808 June 1990 LER 90-001-00:on 900512,reactor Tripped Due to lo-lo Water Level in Steam Generator 2A.Caused by Procedural Inadequacy. Procedure FNP-2-STP-151 Revised to Provide Addl Initial Conditions to Prevent Subj event.W/900608 Ltr ML20012D9591990-03-20020 March 1990 LER 90-002-00:on 900222,two Cases Found Where Surveillance Testing Procedures Did Not Perform All Tests Required by Tech Specs.Caused by Inadequate Procedural Guidance. Procedures revised.W/900320 Ltr ML20012C3031990-03-13013 March 1990 LER 90-001-00:on 900213,fire Watch Not Established within Required Time Period Due to Personnel Error.Administrative Procedure FNP-0-SOP-0.4 Revised & Personnel Retrained on requirements.W/900313 Ltr ML20012B4851990-03-0606 March 1990 LER 83-039/03X-2:on 830726,discovered That Handwheel for Inner Door of Personnel Airlock in Shut Position & Partially Opened.Caused by Excessive Use of Door During Outages.Door Repaired & Returned to Operable status.W/900306 Ltr ML19354E3341990-01-23023 January 1990 LER 89-016-00:on 891228,discovered That Required Surveillance for Plant Vent Stack Radioactive Gas Monitor Not Performed.Caused by Personnel Improperly Scheduling Surveillance for Time Later than Due date.W/900123 Ltr ML20011D5611989-12-18018 December 1989 LER 89-015-00:on 891118,reactor Tripped Due to Turbine Trip. Caused by Voltage Transient in Power Circuit to Digital electro-hydraulic Control Sys & Inverter Failure.Inverter Repaired & Returned to svc.W/891218 Ltr ML19332F9061989-12-13013 December 1989 LER 89-008-00:on 891113,containment Integrity Not Maintained for Approx 30 S.Caused by Personnel in That Inner Door Was Left Blocked Open.Personnel Counseled & Interim Administrative Controls established.W/891213 Ltr ML19332F6761989-12-12012 December 1989 LER 89-007-00:on 891112,both Motor Driven Auxiliary Feedwater Pumps Failed to Start Manually by Operator.Caused by Cognitive Personnel Error Re Design Change.Wiring Discrepancy Corrected & Pump Returned to svc.W/891212 Ltr ML19351A4571989-12-12012 December 1989 LER 89-014-00:from 891115-16,Tech Spec 3.0.3 Entered Voluntarily to Repair Leaking Containment Purge Isolation Dampers.Caused by Need to Repair Dampers.Dampers Closed & Automatic Isolation Feature restored.W/891212 Ltr ML19332F0851989-12-0707 December 1989 LER 89-006-00:on 891112,safety Injection & Reactor Trip Initiated Due to Low Steam Line Pressure.Caused by Personnel Error Involving Misconfiguration of Circuit Valve.Personnel Involved counseled.W/891207 Ltr ML19327C2621989-11-14014 November 1989 LER 89-012-00:on 891018,reactor Tripped Due to lo-lo Steam Generator Level Due to Closure of Governor Valves.Caused by Design Error in Digital electro-hydraulic Control Sys.Valve Position Limiter Feature removed.W/891114 Ltr ML19327C2671989-11-14014 November 1989 LER 89-013-00:on 891019,reactor Tripped Due to lo-lo Level in Steam Generator 2C.Caused by Operator Incorrectly Transferring Steam Generator Level Control to Main Feedwater.Involved Personnel counseled.W/891114 Ltr ML19354D4691989-11-0101 November 1989 LER 89-005-00:on 890930 & 1001,core Alterations Performed W/O Establishing Containment Refueling Integrity.Caused by Cognitive Personnel Error.Personnel Involved in Event Counseled.Containment Procedure strengthened.W/891101 Ltr ML19327B5451989-10-25025 October 1989 LER 89-011-00:on 890925,discovered That Tech Spec 4.6.3.1.a Surveillance Requirement Re Containment Air Lock Outer Door Not Done.Caused by Personnel Error.Individuals Involved Counseled Re Importance of Subj requirements.W/891025 Ltr ML19325D4941989-10-17017 October 1989 LER 89-004-00:on 890616,determined That Calculations Were Not Available to Demonstrate That Svc Water Sys Capable of Supplying Design Flow to safety-related Loads Under Scenario of Seismic event.W/891017 Ltr ML19325D2461989-10-12012 October 1989 LER 89-010-00:on 890920,reactor Tripped Manually Following Loss of Operating Steam Generator Feed Pump.Caused by Inadvertent Opening of Overspeed Trip Test Valve.Individual Involved in Event Counseled to Be More aware.W/891012 Ltr ML19325C7481989-10-10010 October 1989 LER 89-009-00:on 890525,determined That Power Range Nuclear Instrumentation Channels Reading Approx 7% Low.Equalizing Valves on Two of Three Instruments Were Leaking.Valves Repaired & Power Range Instruments adjusted.W/891010 Ltr ML20024F6841983-08-31031 August 1983 LER 83-031/03L-0:on 830806,during Testing,Instrumentation Channel Associated W/Level Transmitter LT-474 Declared Inoperable.Caused by Setpoint Drift of Comparator Card.Card Adjusted & Instrumentation Channel Declared Operable ML20024F6781983-08-31031 August 1983 LER 83-042/03L-0:on 830802,post-LOCA Hydrogen Recombiner 1A Declared Inoperable.Caused by Failure of Temp Indicator.New Indicator Installed & Declared Operable ML20024D0871983-07-26026 July 1983 LER 83-038/03L-0:on 830627,during Turbine Driven Auxiliary Feedwater Pump Inservice Test,Pump Failed to Start from Train a Steam Supply & Declared Inoperable.Caused by Valve HV-3226 Failing to Stroke properly.W/830726 Ltr ML20024C1251983-06-30030 June 1983 LER 83-027/03L-0:on 830607,during Performance of FNP-1-STP-43.0,train a Penetration Room Filtration Sys Declared Inoperable When Exhaust Fan Damper 3357A Would Not Open.Caused by Comparator Card failure.W/830630 Ltr ML20024C4011983-06-22022 June 1983 LER 83-025/03L-0:on 830528,during Calibr Procedure FNP-2-STP-612.0,reactor Coolant Pump 2A Undervoltage Relay 27-3 Declared Inoperable.Caused by Setpoint Drift.Relay Setpoint Adjusted ML20024C4061983-06-22022 June 1983 LER 83-024/03L-0:on 830525,following Increased Count Rate on Containment Atmosphere Particulate Monitoring Sys R-11, RCS Unidentified Leakage Found Above Tech Specs.Cause Not Stated.Loop B Drain Valve Tightened ML20023B5821983-04-29029 April 1983 LER 83-014/03L-0:on 830330,during Surveillance Test of Main Feedwater Pump Turbine 1A,RCS Tavg Decreased Below 541 F. Caused by Overfeeding of Steam Generators Due to Excessive Leak Past Main Feedwater Pump Discharge Valve ML20023B5281983-04-27027 April 1983 LER 83-015/03L-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 ML20023B5321983-04-27027 April 1983 LER 83-012/03L-0:on 830402,overtemp-delta Temp Loop 2 Channel II Declared Inoperable When Bistables 422C1-2 Tripped.Caused by Power Supply Failure of Comparator Card. Card Replaced & Loop Calibr ML20028G3051983-01-28028 January 1983 LER 82-062/03L-0:on 821231,noble Gas Activity Monitor R15 Declared Inoperable.Caused by Blown Fuse.Fuse Replaced & Monitor Returned to Svc ML20028G3111983-01-28028 January 1983 LER 83-001/03L-0:on 830102,RCS Subcooling Monitor Channel 2 Declared Inoperable Following Receipt of Main Control Board Alarms.Caused by Faulty Printed Circuit Card.Connector Pins on Card Cleaned ML20028G3091983-01-28028 January 1983 LER 82-063/03L-0:on 821230,B Train Chlorine Detector Declared Inoperable When Control Room Supply Damper Would Not Close.Caused by Faulty Solenoid Valve.Valve Replaced ML20027D9171982-11-0505 November 1982 LER 82-042/03L-0:on 821013,containment Auxiliary Personnel Hatch Failed to Meet Outer Door Acceptance Criteria.Caused by Worn Gaskets.Gaskets Replaced ML20027D3451982-10-26026 October 1982 LER 82-056/03L-0:on 820927,control Rod Bank D Declared Inoperable When Rods Would Not Move in Manual Control.Caused by Bank Select Relay Sticking,Causing Control Banks B & D to Be Selected Simultaneously.Relay Inspected & Reinstalled ML20027B7491982-09-21021 September 1982 LER 82-038/03L-0:on 820823,inboard & Outboard Pumps of Containment Atmosphere Monitors R-11 (Particulate Monitor) & R-12 (Gaseous Monitor) Declared Inoperable.Caused by Defective Relay & High Flow Switch.Relay & Switch Replaced ML20027B7471982-09-21021 September 1982 LER 82-036/03L-0:on 820824,2B Auxiliary Feedwater Pump Dc Control Power Breaker Inadvertently Opened.Caused by Personnel Error.Breaker Immediately Reclosed & Personnel Counseled ML20027B7461982-09-21021 September 1982 LER 82-051/03L-0:on 820823,1B Control Room Air Conditioner Failed,Rendering B Train Control Room Emergency Air Cleanup Sys Inoperable.Caused by Failed Fan Drive Belts.Belts Replaced & Sys Returned to Svc ML20027B7451982-09-21021 September 1982 LER 82-049/03L-0:on 820822,diesel Generator 1-2A Inadvertently Rendered Inoperable.Caused by Unauthorized Replacement of Lube Oil Strainers & Personnel Error. Generator Returned to Svc ML20052H6541982-04-30030 April 1982 LER 82-015/03L-0:on 820408,radiation Monitor 25A (Spent Fuel Storage Pool Area Gaseous activity-ventilation Sys Isolation) Declared Inoperable While Performing Test.Caused by Dirty Contacts on Mod Selector Switch.Contacts Cleaned ML20052H6591982-04-30030 April 1982 LER 82-017/03L-0:on 820413,FI-497 (Steam Generator 1C Feedwater Flow) Instrumentation Channel Declared Inoperable When Max Allowable Channel Check Error Was Exceeded.Caused by Faulty Transmitter Amplifier Card.Card Replaced ML20052C1391982-04-22022 April 1982 LER 82-014/03L-0:on 820326,28 & 0408,B Train Chlorine Detector Declared Inoperable Due to Detector Tape Not Advancing.Caused by Movement Indicator Binding Detector Tape & Sheared Pin in Tape Drive Mechanism ML20052C1371982-04-22022 April 1982 LER 82-014/03L-0:on 820328,while Performing Calibr & Functional Test,T average-low-low B Instrumentation Loop Declared Inoperable Due to Indicator Reading.Caused by Setpoint Drift.Power Supply Card Replaced ML20052C1401982-04-22022 April 1982 LER 82-015/03L-0:on 820325,radiation Monitor R29B Instrumentation Channel Declared Inoperable When Displays on All Readout Consoles Were Inaccurate.Caused by Dirty Contacts & Faulty Link.Contacts Cleaned ML20052C1351982-04-22022 April 1982 LER 82-012/03L-0:on 820326,during Routine Insp,Turbine Driven Auxiliary Feedwater Pump Declared Inoperable When Outboard Bearing Oil Bubbler Found Broken & Oil Drained. Possibly Caused by Workers Handling Scaffolding in Area ML20052A6571982-04-16016 April 1982 LER 82-013/03L-0:on 820317,containment Atmosphere Activity Monitors R-11 (Particulate Monitor) & R-12 (Gaseous Monitor) Declared Inoperable Due to Failure of Vacuum Pump.Caused by Failed Outboard Pump.Filter & Gasket Replaced ML20052A6671982-03-25025 March 1982 LER 82-009/03L-0:on 820228,instrumentation Loop Associated w/FT-474 (Steam Generator a Flow Transmitter) Declared Inoperable.Caused by Leaking Equalizing Valve.Valve Stem Repaired ML20052A6611982-03-25025 March 1982 LER 82-005/03L-0:on 820226,4160-volt B Train Ac Electrical Power Circuit Declared Inoperable When Emergency Bus 2G de-energized.Bus 2G de-energized When Breaker 2-DG15 Opened. Cause Under Investigation ML20052A6711982-03-25025 March 1982 LER 82-010/03L-0:on 820226,instrumentation Loop Associated w/LI-474 (Steam Generator a Level Indicator) Declared Inoperable.Caused by Loss of Necessary Level in Ref Leg While Steam Generator Not in Svc.Leg Refilled ML20052A6631982-03-25025 March 1982 LER 82-008/03L-0:on 820226,instrumentation Loop Associated w/LI-485 (Steam Generator B Level Indication) Declared Inoperable When Reading Was Out of Tolerance W/Other Channels.Caused by Obstruction in Ref Leg ML20050C1861982-03-19019 March 1982 LER 82-006/01T-0:on 820310,levels in Fire Protection Tanks a & B Fell to Approx 85,000 Gallons Each as Result of Inadvertent Actuation of Fire Protection Deluge Sys on Cooling Tower 1A.Caused by Personnel Error 1993-07-23
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML20217P0761999-10-0606 October 1999 Non-proprietary, Farley Units 1 & 2 LBB Calculation Results Due to SG Replacement & SG Snubber Elimination Programs ML20217G0361999-09-30030 September 1999 Monthly Operating Repts for Sept 1999 for Jm Farley Nuclear Plant,Units 1 & 2.With ML20212E7451999-08-31031 August 1999 Monthly Operating Rept for Aug 1999 for Hcgs,Unit 1.With Summary of Changes,Tests & Experiments Implemented During Aug 1999.With ML20216E4941999-08-31031 August 1999 Monthly Operating Repts for Aug 1999 for Jmfnp.With ML20210T2161999-08-0606 August 1999 Draft SE Supporting Proposed Conversion of Current TS to ITS for Plant ML20211B2011999-08-0404 August 1999 Informs Commission About Results of NRC Staff Review of Kaowool Fire Barriers at Farley Nuclear Plant,Units 1 & 2 & Staff Plans to Address Technical Issues with Kaowool & FP-60 Barriers ML20210R6031999-07-31031 July 1999 Monthly Operating Repts for July 1999 for Jm Farley Nuclear Plant,Units 1 & 2.With ML20196J3791999-06-30030 June 1999 Safety Evaluation of TR WCAP-14750, RCS Flow Verification Using Elbow Taps at Westinghouse 3-Loop Pwrs. Rept Acceptable ML20209G0661999-06-30030 June 1999 Monthly Operating Repts for June 1999 for Jm Farley Nuclear Plant,Units 1 & 2.With L-99-267, Monthly Operating Repts for June 1999 for Jm Farley Nuclear Plant,Units 1 & 2.With1999-06-30030 June 1999 Monthly Operating Repts for June 1999 for Jm Farley Nuclear Plant,Units 1 & 2.With L-99-023, Monthly Operating Repts for May 1999 for Jfnp Units 1 & 2. with1999-05-31031 May 1999 Monthly Operating Repts for May 1999 for Jfnp Units 1 & 2. with ML20206G7471999-05-0404 May 1999 Safety Evaluation Accepting Corrective Actions Taken by SNC to Ensure That Valves Perform Intended Safety Functions & Concluding That SNC Adequately Addressed Requested Actions in GL 95-07 L-99-020, Monthly Operating Repts for Apr 1999 for Jm Farley Nuclear Plant,Units 1 & 2.With1999-04-30030 April 1999 Monthly Operating Repts for Apr 1999 for Jm Farley Nuclear Plant,Units 1 & 2.With ML20206C9461999-04-30030 April 1999 1:Final Cycle 16 Freespan ODSCC Operational Assessment L-99-161, Monthly Operating Repts for Mar 1999 for Jm Farley Nuclear Plant,Units 1 & 2.With1999-03-31031 March 1999 Monthly Operating Repts for Mar 1999 for Jm Farley Nuclear Plant,Units 1 & 2.With ML20205N0961999-03-31031 March 1999 Monthly Operating Repts for Mar 1999 for Jm Farley Nuclear Plant,Units 1 & 2.With ML20204D7271999-03-15015 March 1999 ISI Refueling 15,Interval 2,Period 3,Outage 3 for Jm Farley Nuclear Generating Plant,Unit 1 ML20207M6421999-02-28028 February 1999 Monthly Operating Repts for Feb 1999 for Jm Farley Nuclear Plant,Units 1 & 2.With ML20203A2651999-01-31031 January 1999 Monthly Operating Repts for Jan 1999 for Jm Farley Nuclear Plant,Units 1 & 2.With ML20199D8611999-01-12012 January 1999 SER Accepting Relief Request for Inservice Insp Program for Plant,Units 1 & 2 ML20199E6591998-12-31031 December 1998 Monthly Operating Repts for Dec 1998 for Jm Farley Nuclear Plant,Units 1 & 2.With ML20206C8081998-12-31031 December 1998 Alabama Power 1998 Annual Rept ML20198K4091998-12-18018 December 1998 COLR for Jm Farley,Unit 1 Cycle 16 ML20198B2561998-11-30030 November 1998 Monthly Operating Repts for Nov 1998 for Jm Farley Nuclear Plant,Units 1 & 2.With ML20195E2281998-11-16016 November 1998 Safety Evaluation Authorizing Relief Request for Second 10-year ISI Program Relief Request 56 for Plant,Unit 1 ML20195C9681998-10-31031 October 1998 Monthly Operating Repts for Oct 1998 for Jm Farley Nuclear Plant,Units 1 & 2.With ML20155E0271998-10-29029 October 1998 SER Approving & Denying in Part Inservice Testing Program Relief Requests for Plant.Relief Requests Q1P16-RR-V-3 & Q2P16-RR-V Denied Since Requests Do Not Meet Size Requirement of GL 89-04 ML20154B6121998-10-0101 October 1998 Safety Evaluation Granting Second 10-year ISI Requests for Relief RR-13 & RR-49 Through RR-55 for Jm Farley NPP Unit 1 ML20151V8341998-09-30030 September 1998 Non-proprietary Rev 2 to NSA-SSO-96-525, Jm Farley Nuclear Plant Safety Analysis IR Neutron Flux Reactor Trip Setpoint Change ML20154H6001998-09-30030 September 1998 Monthly Operating Repts for Sept 1998 for Jm Farley Nuclear Plant,Units 1 & 2.With ML20154H0121998-09-30030 September 1998 Submittal-Only Screening Review of Farley Nuclear Plant IPEEE (Seismic Portion) ML20197C8991998-08-31031 August 1998 Monthly Operating Repts for Aug 1998 for Jm Farley Nuclear Plant,Units 1 & 2.With ML20237C5471998-08-20020 August 1998 Suppl to SE Re Amends 137 & 129 to Licenses NPF-2 & NPF-8, Respectively.Se Being Supplemented to Incorporate Clarifications/Changes & Revise Commitment for Insp of SG U-bends in Rows 1 & 2 for Unit 2 Only ML20236Y1121998-07-31031 July 1998 Voltage-Based Repair Criteria 90-Day Rept ML20237B1891998-07-31031 July 1998 Monthly Operating Repts for July 1998 for Jm Farley Nuclear Plant,Units 1 & 2 ML20237A2181998-07-24024 July 1998 Jm Farley Unit 2 ISI Rept Interval 2,Period 3 Outage 1, Refueling Outage 12 ML20236U6141998-07-23023 July 1998 Safety Evaluation Authorizing Use of Alternative Alloy 690 Welds (Inco 52 & 152) as Substitute for Other Weld Metal ML20236R8671998-07-0909 July 1998 Safety Evaluation Concluding That Southern Nuclear Operating Co USI A-46 Implementation Program Has Met Purpose & Intent of Criteria in GIP-2 & Staff SSER-2 on GIP-2 for Resolution of USI A-46 ML20236M5981998-06-30030 June 1998 Monthly Operating Repts for June 1998 for Jm Farley Nuclear Plant,Units 1 & 2 ML20154H0461998-06-30030 June 1998 Technical Evaluation Rept on Review of Farley Nuclear Plant IPEEE Submittal on High Winds,Flood & Other External Events (Hfo) ML20248M3121998-05-31031 May 1998 Monthly Operating Repts for May 1998 for Jm Farley Nuclear Plant,Units 1 & 2 ML20247F3631998-04-30030 April 1998 Monthly Operating Repts for Apr 1998 for Jm Farley Nuclear Plant,Units 1 & 2 ML20217D2591998-04-21021 April 1998 Safety Evaluation Accepting Licensee Proposed Alternative Re Augmented Exam of Reactor Vessel Shell Welds for Plant ML20247E8851998-03-31031 March 1998 FNP Unit 2 Cycle 13 Colr ML20217H3191998-03-31031 March 1998 Safety Evaluation Accepting Proposed Changes to Plant Matl Surveillance Programs ML20216D5941998-03-31031 March 1998 Monthly Operating Repts for Mar 1998 for Joseph M Farley Nuclear Plant,Units 1 & 2 ML20217D4081998-03-24024 March 1998 Safety Evaluation Accepting Proposed Changes to Maintain Calibration Info Required by ANSI N45.2.4-1972 ML20216H6731998-03-17017 March 1998 SER Accepting Quality Assurance Program Description Change for Joseph M Farley Nuclear Plant,Units 1 & 2 ML20216J6851998-03-16016 March 1998 Revised Pages 58 & 59 to Fnp,Units 1 & 2,Power Uprate Project BOP Licensing Rept ML20216D9811998-02-28028 February 1998 Monthly Operating Repts for Feb 1998 for Jm Farley Nuclear Plant,Units 1 & 2 1999-09-30
[Table view] |
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, 40 inv6 vss Comer Parks'y Post Office Box 1295 Birmingham, Alabama 35201 Telephone 705 066 5!,81 W. Q. Heireton, til Senior Vice Pre sident ggggg
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Nuclear Operatir>ns the saathom electrc system 10 CFR 50.73 October 17. 1989 Docket No. 50-348 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Vashington, D.C. 20555 Dear Sir Joseph M. Farley Nuclear Plant - Unit 1 LJcensee Event Report No. LER 89-004-00 Joseph H. Farley Nuclear Plant, Unit 1, Licensee Event Report No. LER 89-004-00 is being submitted in accordance with 10CFR50.73.
If you have any questions, please advise.
i Respectfully s ted,
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1 On June 16, 1989, during a Self-Initiated Safety System Assessment (SSSA) of the Service Vater System, it was determined that calculations t vere not available to demonstrate that the service water system was capable of rupplying design flov to safety related loads under the
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I l scenario of zn LOSP, a seismic event, or combination of these two j events and that those scenarios may be more limiting than the assumed ,
design condition for the service water system.
The original design assumed the LOCA vith LOSP vould be the bounding scenario for d' other postulated events. The LOCA vith LOSP event generates an St signal, isolating major non-safety rel3ted loads on the service water r stem.
l The LOSP, seismic, or combination LOSP/ seismic events postulated by the SS5A vould not result in the automatic isolation of major non-=afety related service water loads and therefore may represent e more limiting design condition for the system.
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Vestinghou1e - Pressurized Vater Reactor Energy Industry Identification System coder are identified in the text as l IXX). '
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i Summary of Event !
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On June 16, 1989, during a self-Initiated Safety System Assessment (SSSA) of the Service Vater System [BI), it was determined that calculations were not availabic to demonstrate that the service water system was capable of ;
supplying design flow to safety related loads under the scenario of an LOSP, a seismic event, or combination of these two events. The SSSA team !
discovered that these scenarios may be more limiting than the assumed design condition for the service water system.
The original design assumed the LOCA vith LOSP vould be the bounding scenario for all other postulated events. The LOCA vith LOSP event -
generates an SI signal, isolating major non-safety related service water loads. ,
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The LOSP, seismic, or combination LOSP/ Seismic events postulated by the SSSA l
' vould not result in the autor.atic isolation of major non-safety related service water loads and therefore may represent a more limiting design ,
condition for the system. '
Background Information l ,
l i In 1988, Alabama Power Company made the decision to conduct a self-initiated safety system assessment. The purpose of the assessment was to evaluate i
the ef fectiveness of the existing Configuration Management program for Farley Nuclear Plant. A detailed SSSA plan was developed which delineated
- the methodology for conducting the assessment, including the means for addressing SSSA.
operability and reportability concerns identified during the ;
- June 19-23,A team of 10 personnel coniucted the SSSA on May 22-26, June 5-9, and 1989, i
Description of Event
! i on June 16, 1989 based on the SSSA team documented finding, it was determined that a potential problem with the system capability for supplying design flow to safety related loads under the scenario of an LOSP, seismic event, or combination LOSP and seismic event existed. On June 16, revisions to operatti.c procedores vere implemented to isolate significant non-safety related loads upon from a seismic ev(nt.indication of an LOSP or a major lice break resulting These compensatory measures are being implemented
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until further evalu0tien and analysis can be conducted.
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Cause of Event j The original Service Water system design assumed the LOCA vith LOSF event ,
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would be the bounding oesign condition for the system. Tbs cause of this ;
i event was that the original assumption appears to be in error. No l
- documented evidence could be found to demonstrate that the original design assumption was a more limiting design condition than the scenarios i
identified by the SSSA. j Reportabili,ty Analysis and Safety Assessment When the potential concern with the service water flov balance was i
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identified in June, prompt actions were taken to establish interim
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compensatory measures and the NEC resident inspector was notified.
The service water system was considered operable based on the establishment of interim compensatory measures, j l
i In June when the flow balance concern was ra'. sed, reportability of the event was addressed. At that time, available flov balance calculations did not conclusively show that inadequate flow rates to safety related ,
components would occur during an LOSP and/or seismic event. Tnus, it was ;
determined that there was no known condition which constituted a reportable condition. Upon completi n of the service water flow balance model development, reportability would again be evaluated. The model is I currently scheduled for c.c.ipletion in February 1990. I l In September 1989, Alabre 1 Power Company briefed NRC Region II management on the status of the SSL program. Based on discussions with the staff,
! Mabama Power Company decided to submit a voluntary report concerning the
- potential flow inadequacy.
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Corractive Action In June 1989, when the SFSA team notified Farley Nuclear Plant of the potential l' flow balance concern, interim compensatory measures were taken. These measures vere implemented priot to co'rpletion of the SSSA. The measures consisted of revising plant procedures to require operator actions to isolate the turbine r building and other major non-safety related loads upon indication of an 14SP or a !
major line break resulting from a seismic event. A1.1 on-shift licensed personnel vere ir. formed of the potential concern via Operatiers Night Orders. A subsequent training notice was issued to all licensed personnel noting the :
procedure changes implemented as interim compensatory actions and other concerns and procedure changes resulting from the SSSA. In September 1989, during a :
review of the SSSA corrective action status, several of the operations procedures ;
I vere further revised to provide additional guidance to the operators. i
A flow balance model is currently being developed such that the LOSP and/or seismic events can be accurately and quantitatively analyzed to demonstrate
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adequate flov vill exist to all safety related components. The model is still in the development stage vitti verification of inputs being performed and actual '
field flow measuremer , planned to validate the model versus the current field conditions. The model is scheduled for completion by Februar* 1990.
,
Based on the results of the service water S$$A, Alabama Pov t Company performed a ,
mini-SSSA on the component cooling vater (CCV) system (which was focused on '
assessing the design of the CCW system). No significant design analysis weaknesses i vare found. In addition, Alabama Power Company Intends to continue ito SSSA program '
, to review other selected safety systems during the next three to five years.
'
T % refore, a program is in place to correct service water issues and to evaluate the 1 original design assumptions for other safety systems, i 1 '
Adi'!. fonal Informatien No components failed during this event.
4 No similar 1.F.Rs have been submitted by farley Nuclear PJant. '
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