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Category:LICENSEE EVENT REPORT (SEE ALSO AO
MONTHYEARML17355A3891999-07-20020 July 1999 LER 99-001-00:on 990623,manual Rt from 100% Power Following Multiple Control Rod Drops Was Noted.Caused by Manual Action Taken by Reactor Control Operator.Inspected & Repaired Stationary Gripper Regulating Cards.With 990720 Ltr ML17354B1921998-11-18018 November 1998 LER 98-007-00:on 981020,containment Purge Supply,Valve Opened Wider than TS Limit.Caused by Improper Setting of Mechanical Stops.Incorporated Improved Standard Method of Measuring Angular Valve Position Into Sp.With 981118 Ltr ML17354B1361998-10-16016 October 1998 LER 98-004-00:on 980921,automatic Reactor Trip Occurred. Caused by Inadequate re-correlation of Intermediate Range Neutron Flux Instrumentation Reactor Trip Bistable. Enhanced Applicable Plant Procedures.With 981016 Ltr ML17354B0341998-07-15015 July 1998 LER 98-003-00:on 980619,discovered That Auxiliary Feedwater Sys Was Inoperable Due to Inadequate Inservice Testing of Valves.Caused by Misunderstanding of Testing Criteria.Util Revised Procedures & Verified Operability of Valves ML17354A9841998-06-18018 June 1998 LER 97-007-01:on 970730,automatic Reactor Trip Occurred Due to Closure of B Msiv.Caused by Failed BFD22S Relay.Six Relays on 3A,3B & 3C MSIVs Were Replaced & Implemented Plant Change to Disable Electronic Trip Function on 3 AFW Pumps ML17354A9741998-06-0909 June 1998 LER 98-002-00:on 980513,discovered Potential LOCA-initiated Electrical Fault Which Places ECCS Outside Design Basis. Caused by Inadequate Review of Effect on non-safety Circuit failures.Re-powered PC-*-600A Relays ML17354A8511998-03-24024 March 1998 LER 97-009-01:on 971114,discovered That CR Console Switch for 3B Sgfp Was Not in Start Position.Caused by Inadequate Procedural Guidance.Revised Procedures 3/4-OP-074,informed Personnel of Event & Performed Walkdown of CR ML17354A8441998-03-18018 March 1998 LER 98-001-00:on 980216,manual Reactor Trip Occurred Due to Loss of Turbine Control Oil Pressure W/Steam Leak in Auxiliary Feedwater Steam Supply Piping.Auxiliary Governor Maint Instructions Will Be revised.W/980318 Ltr ML17354A7361997-12-12012 December 1997 LER 97-009-01:on 971114,identified That CR Console Switch for 3B SG Feedwater Pump Was Not in Start Position.Caused by Inadequate Procedural Guidance.Procedures 3/4-OP-074,SGFP Were revised.W/971212 Ltr ML17354A6801997-10-0808 October 1997 LER 97-008-00:on 970909,containment Sump Debris Screens Outside Design Basis Due to Stress Damage Was Discovered. Caused by Inadequate Procedural Guidance & Personnel Error. Discrepancies Found on Screens corrected.W/971008 Ltr ML17354A6121997-08-29029 August 1997 LER 97-007-00:on 970730,automatic Reactor Trip Occurred. Caused by Closure of B Main Steam Isolation Valve.Failed W Relay & Equivalent Relays Were replaced.W/970829 Ltr ML17354A6081997-08-18018 August 1997 LER 97-006-00:on 970722,manual Reactor Trip Occurred Due to Failed Rod Control Power Supplies.Replaced Twelve Power Supplies in Rod Control Logic & Power cabinets.W/970818 Ltr ML17354A5801997-07-14014 July 1997 LER 97-005-00:on 970618,RCP Oil Collection Sys Was Found Outside Design Basis.Caused Because Design Did Not Consider Component Parts to Be Potential Leakage Sources.Entire RCP Oil Collection Sys Was reviewed.W/970714 Ltr ML17354A5141997-05-22022 May 1997 LER 97-002-00:on 970423,automatic Reactor Tripped.Caused by Actuation of Turbine Overspeed Protection Circuit. Administrative Procedures Governing Inadequate Work Controls Will Be Revised to Capture Lessons learned.W/970522 Ltr ML17354A5061997-05-0909 May 1997 LER 97-003-00:on 970410,mode Changed W/O Meeting Requirements of TS 3.0.4 Due to Inadequate Procedural Guidance.Night Order Was Issued to Inform Personnel That S/G Blowdown Keylock Switches Were Left in drain.W/970509 Ltr ML17354A5051997-05-0909 May 1997 LER 97-004-00:on 970411,auxiliary Feedwater Automatic Start Upon Trip of All Main Feedwater Pumps,Occurred.Caused by Mispositioned Valve Closing.Valves Listed as Inappropriately Positioned Were repositioned.W/970509 Ltr ML17354A4781997-04-25025 April 1997 LER 97-001-00:on 970327,ECCS Recirculation Loop Leakage Was Found to Be in Condition Outside Design Basis Due to Gasket Movement During Installation During Spring 1966 Reassembly. Gasket Replaced & Pump tested.W/970425 Ltr ML17354A4581997-03-28028 March 1997 LER 97-002-00:on 970303,manual Reactor Trip Following Rod Control Urgent Failure Alarm Occurred.Caused by Phase Failure Detection on Stationary a Circuits of 2BD Rod Control Cabinet.Air Conditioning replaced.W/970328 Ltr ML17354A4511997-03-26026 March 1997 LER 97-001-00:on 970118,missed Surveillance on CR Position Verification Occurred Due to Inoperable Rod Deviation Monitor.Faulty Circuit Common Connection Was Corrected & Rdm Operability Was restored.W/970326 Ltr ML17354A4061997-02-0303 February 1997 LER 96-004-03:on 970107,identified Three Instances of Inadequate Surveillance Testing.Caused by Inadequate Surveillance Procedures.Surveillance Procedures Revised ML17354A3771996-12-27027 December 1996 LER 96-012-00:on 961204,determined Containment Average Temp Being Determined Based on Only Two Temp Elements Instead of Three as Required by Tss.Caused by Log Only Requiring One Entry.Log revised.W/961227 Ltr ML17354A3261996-11-0606 November 1996 LER 96-011-00:on 961009,potential for Overpressurizing Post Accident Containment Vent Filter Housings Occurred.Caused by Improper Change Mgt.Monitoring Sys Operating Procedures revised.W/961106 Ltr ML17354A3071996-10-22022 October 1996 LER 96-010-00:on 960924,manual Reactor Shutdown Occurred. Caused by Failed Rod Control Sys Regulation Card in 2AC Power cabinet.2AC Power Cabinet DC Power Supplies,Cabling & Connectors checked.W/961022 Ltr ML17353A8711996-08-27027 August 1996 LER 96-009-00:on 960729,failed to Reflect Heavy Load Design Info in Procedural Controls.Caused by Failure to Incorporate 1982 Procedure Changes.Suspended Lifting of Heavy Loads & Took Turbine Bldg Crane OOS.W/960827 Ltr ML17353A7411996-06-18018 June 1996 LER 96-008-00:on 960521,surveillance Method for Testing Emergency Diesel Generators (EDG) Determined Inadequate. Caused by Personnel Error.All Four EDGs Rapid Start Tested & EDG Surveillance Procedures modified.W/960618 Ltr ML17353A7401996-06-18018 June 1996 LER 96-004-02:on 960524,identified Inadequate Surveillance Testing.Caused by Inadequate Surveillance Procedures.Entered Tech Spec Statements,Tested Required Instruments Functions & Revised Plant procedure.W/960618 Ltr ML17353A6901996-05-13013 May 1996 LER 96-004-01:on 960220,identified Potential Tech Spec non-compliance Associated W/Surveillance Testing of AFW Actuation Circuitry on Sg.Caused by Inadequate Surveillance Procedures.Procedures revised.W/960513 Ltr ML17353A6741996-05-0606 May 1996 LER 96-001-00:on 960409,manual Rt Occurred Due to Turbine Governer Control Oil Perturbation.Disassembled & Inspected Governor Valve for Cleanliness & Corrosion products.W/960506 Ltr ML17353A6651996-04-29029 April 1996 LER 96-007-00:on 960329,inadvertent ESF Actuation Occurred During Refueling Outage Due to Cognitive Personnel Error. Personnel Involved Counseled & Integrated Safeguards Test Procedures Being revised.W/960429 Ltr ML17353A6601996-04-25025 April 1996 LER 96-006-00:on 960327,manual Rt Occurred Due to 3C Transformer Lockout & Loss of 3B SG Mfp.Replaced SAM Timer Relay in 3AC16.W/960425 Ltr ML17353A6491996-04-23023 April 1996 LER 96-005-00:on 960326,certain Safety Injection Accumulator Filled Evolutions Resulted in cross-tied Configuration.C/A: Night Order Written & Operations Procedure 3/4-OP-064 revised.W/960423 Ltr ML17353A6051996-03-18018 March 1996 LER 96-003-00:on 960222,two Arpi Inoperable & TS 3.0.3 Entered.Proposed License Amend Submitted to Revise Allowed Misalignment from +/-12 Steps to =/-18 Steps Between Arpi & Dpi at Less than 90% power.W/960318 Ltr ML17353A6041996-03-18018 March 1996 LER 96-004-00:on 960220,surveillance Testing of AFW Actuation Circuitry Was Inadequate.Caused by Inadequate Surveillance Procedures.Tested Untested Portions of Actuation Logic for AFW Automatic Start signal.W/960318 Ltr ML17353A5861996-03-0606 March 1996 LER 96-002-00:on 960209,automatic Turbine Trip/Rt Occurred Due to High SG Level.Caused by Personnel Error.Replaced Both Hinge Pins on B Sgfp Discharge Check valve.W/960306 Ltr ML17353A5761996-03-0101 March 1996 LER 96-001-00:on 960131,intake CWS Flow Rates Found W/ Potential to Be Less than Required by Design Basis.Caused by Influx of Aquatic Grass & Algae Onto Basket Strainers of Icw Flow Path.Mechanically Cleaned strainers.W/960301 Ltr ML17353A4451995-11-0909 November 1995 LER 95-007-00:on 951017,manual Rt Occurred Following Drop of Four Control Rods.Caused by Water Intrusion Into Rod Control Power Cabinet 2BD.Inspected Control Power Cabinet 2BD for Other Water damage.W/951109 Ltr ML17353A4241995-10-12012 October 1995 LER 95-006-00:on 950913,analysis Showed That CCW Exchangers Susceptible to Damage Due to flow-induced Vibration.Ccw Sys Has Been Flow Balanced to Closer tolerances.W/951012 Ltr ML17353A3601995-09-13013 September 1995 LER 95-005-00:on 950818,containment Pressure Testing Procedure Resulted in Inhibiting Both Trains of Containment Pressure from Initiated Esf.Revised Procedure to Require Testing of Each Train separately.W/950913 Ltr ML17353A2951995-07-17017 July 1995 LER 94-005-02:on 941103,both Units Outside Design Basis Due to Design Defect in Safeguards Bus Sequencer Test Logic. Resumed Monthly Manual Testing of Sequencer ML17352B1581995-05-0505 May 1995 LER 95-004-00:on 950407,unit Being Shutdown to Investigate Recurring non-urgent Failure Alarms from Redundant Rod Control Power Supplies.Reactor Manually Tripped.All Four PS-3 Power Supplies replaced.W/950505 Ltr ML17352B1181995-04-0707 April 1995 LER 95-003-00:on 950309,intake Cooling Water Flow Rate Through CCW Heat Exchangers Fell Below Assumed Design Basis. Caused by an Influx of Aquatic Grass & Algae Onto Basket Strainers.Strainers cleaned.W/950407 Ltr ML17352B0701995-03-13013 March 1995 LER 95-002-00:on 950215,inadequate Definition of Loops Filled Resulted in Units in Condition Prohibited by Ts. Issued TS Position Statement to Define Term Loops Filled as Used in TS 6.4.1.1.4.W/950313 Ltr ML17352B0321995-02-0909 February 1995 LER 94-005-01:on 941103,design Defect Found in Safeguards Bus Sequencer Test Logic,Placing Facility Outside Design Basis.Design Mods to Eliminate Software Logic Problems Will Be Implemented During Next Refueling outages.W/950209 Ltr ML17352B0101995-01-20020 January 1995 LER 94-006-00:on 941226,C Main Feedwater Control Valve Failed Closed,Causing Reactor & Turbine Trips.Caused by Loose Screw Terminal Connection.I/P Transducers Replaced W/ New Model W/Different Design Wire connection.W/950120 Ltr ML17352A9511994-12-13013 December 1994 LER 94-006-00:on 941130,Unit 4 Tripped Automatically.Caused by Failure of Flexible Link Connection Between Main Generator B Phase Bus & Associated Isolated Phase Bus Bar. All Bolts on Flexible Link checked.W/941213 Ltr ML17352A8871994-11-10010 November 1994 LER 94-005-00:on 941103,design Defect in Safeguards Bus Sequencer Test Logic Places Both Units Outside Design Basis. Caused by 3A Sequencer Failed to Respond as Expected to Opposite Unit SI signal.W/941110 Ltr ML17352A8851994-11-10010 November 1994 LER 94-004-00:on 941103,Unit 3 Outside Design Basis Due to Two of Three Required Safety Injection Pumps Inoperable. Control Switches for 3A & 3B Safety Injection Pumps Immediately Returned to automatic.W/941110 Ltr ML17352A8421994-10-21021 October 1994 LER 94-004-00:on 940923,Unit 4 Tripped Automatically from Rated Power.Caused by Faulty Regulator Transistor.Faulty Backup Power Supply Replaced & Maint History for Power Supplies reviewed.W/941021 Ltr ML17352A8431994-10-20020 October 1994 LER 94-005-00:on 940924,Unit 4 Manually Tripped.Caused by Manual Actuation.Light Bulb & Socket replaced.W/941020 Ltr ML17352B1671994-08-16016 August 1994 LER 94-003-00:on 940720 & 21,util Discovered That Several Required Valve Stroke Time Surveillances Had Not Been Performed.Caused by Personnel Error.Personnel Reassigned & Procedures and Surveillance Tracking Software Enhanced 1999-07-20
[Table view] Category:RO)
MONTHYEARML17355A3891999-07-20020 July 1999 LER 99-001-00:on 990623,manual Rt from 100% Power Following Multiple Control Rod Drops Was Noted.Caused by Manual Action Taken by Reactor Control Operator.Inspected & Repaired Stationary Gripper Regulating Cards.With 990720 Ltr ML17354B1921998-11-18018 November 1998 LER 98-007-00:on 981020,containment Purge Supply,Valve Opened Wider than TS Limit.Caused by Improper Setting of Mechanical Stops.Incorporated Improved Standard Method of Measuring Angular Valve Position Into Sp.With 981118 Ltr ML17354B1361998-10-16016 October 1998 LER 98-004-00:on 980921,automatic Reactor Trip Occurred. Caused by Inadequate re-correlation of Intermediate Range Neutron Flux Instrumentation Reactor Trip Bistable. Enhanced Applicable Plant Procedures.With 981016 Ltr ML17354B0341998-07-15015 July 1998 LER 98-003-00:on 980619,discovered That Auxiliary Feedwater Sys Was Inoperable Due to Inadequate Inservice Testing of Valves.Caused by Misunderstanding of Testing Criteria.Util Revised Procedures & Verified Operability of Valves ML17354A9841998-06-18018 June 1998 LER 97-007-01:on 970730,automatic Reactor Trip Occurred Due to Closure of B Msiv.Caused by Failed BFD22S Relay.Six Relays on 3A,3B & 3C MSIVs Were Replaced & Implemented Plant Change to Disable Electronic Trip Function on 3 AFW Pumps ML17354A9741998-06-0909 June 1998 LER 98-002-00:on 980513,discovered Potential LOCA-initiated Electrical Fault Which Places ECCS Outside Design Basis. Caused by Inadequate Review of Effect on non-safety Circuit failures.Re-powered PC-*-600A Relays ML17354A8511998-03-24024 March 1998 LER 97-009-01:on 971114,discovered That CR Console Switch for 3B Sgfp Was Not in Start Position.Caused by Inadequate Procedural Guidance.Revised Procedures 3/4-OP-074,informed Personnel of Event & Performed Walkdown of CR ML17354A8441998-03-18018 March 1998 LER 98-001-00:on 980216,manual Reactor Trip Occurred Due to Loss of Turbine Control Oil Pressure W/Steam Leak in Auxiliary Feedwater Steam Supply Piping.Auxiliary Governor Maint Instructions Will Be revised.W/980318 Ltr ML17354A7361997-12-12012 December 1997 LER 97-009-01:on 971114,identified That CR Console Switch for 3B SG Feedwater Pump Was Not in Start Position.Caused by Inadequate Procedural Guidance.Procedures 3/4-OP-074,SGFP Were revised.W/971212 Ltr ML17354A6801997-10-0808 October 1997 LER 97-008-00:on 970909,containment Sump Debris Screens Outside Design Basis Due to Stress Damage Was Discovered. Caused by Inadequate Procedural Guidance & Personnel Error. Discrepancies Found on Screens corrected.W/971008 Ltr ML17354A6121997-08-29029 August 1997 LER 97-007-00:on 970730,automatic Reactor Trip Occurred. Caused by Closure of B Main Steam Isolation Valve.Failed W Relay & Equivalent Relays Were replaced.W/970829 Ltr ML17354A6081997-08-18018 August 1997 LER 97-006-00:on 970722,manual Reactor Trip Occurred Due to Failed Rod Control Power Supplies.Replaced Twelve Power Supplies in Rod Control Logic & Power cabinets.W/970818 Ltr ML17354A5801997-07-14014 July 1997 LER 97-005-00:on 970618,RCP Oil Collection Sys Was Found Outside Design Basis.Caused Because Design Did Not Consider Component Parts to Be Potential Leakage Sources.Entire RCP Oil Collection Sys Was reviewed.W/970714 Ltr ML17354A5141997-05-22022 May 1997 LER 97-002-00:on 970423,automatic Reactor Tripped.Caused by Actuation of Turbine Overspeed Protection Circuit. Administrative Procedures Governing Inadequate Work Controls Will Be Revised to Capture Lessons learned.W/970522 Ltr ML17354A5061997-05-0909 May 1997 LER 97-003-00:on 970410,mode Changed W/O Meeting Requirements of TS 3.0.4 Due to Inadequate Procedural Guidance.Night Order Was Issued to Inform Personnel That S/G Blowdown Keylock Switches Were Left in drain.W/970509 Ltr ML17354A5051997-05-0909 May 1997 LER 97-004-00:on 970411,auxiliary Feedwater Automatic Start Upon Trip of All Main Feedwater Pumps,Occurred.Caused by Mispositioned Valve Closing.Valves Listed as Inappropriately Positioned Were repositioned.W/970509 Ltr ML17354A4781997-04-25025 April 1997 LER 97-001-00:on 970327,ECCS Recirculation Loop Leakage Was Found to Be in Condition Outside Design Basis Due to Gasket Movement During Installation During Spring 1966 Reassembly. Gasket Replaced & Pump tested.W/970425 Ltr ML17354A4581997-03-28028 March 1997 LER 97-002-00:on 970303,manual Reactor Trip Following Rod Control Urgent Failure Alarm Occurred.Caused by Phase Failure Detection on Stationary a Circuits of 2BD Rod Control Cabinet.Air Conditioning replaced.W/970328 Ltr ML17354A4511997-03-26026 March 1997 LER 97-001-00:on 970118,missed Surveillance on CR Position Verification Occurred Due to Inoperable Rod Deviation Monitor.Faulty Circuit Common Connection Was Corrected & Rdm Operability Was restored.W/970326 Ltr ML17354A4061997-02-0303 February 1997 LER 96-004-03:on 970107,identified Three Instances of Inadequate Surveillance Testing.Caused by Inadequate Surveillance Procedures.Surveillance Procedures Revised ML17354A3771996-12-27027 December 1996 LER 96-012-00:on 961204,determined Containment Average Temp Being Determined Based on Only Two Temp Elements Instead of Three as Required by Tss.Caused by Log Only Requiring One Entry.Log revised.W/961227 Ltr ML17354A3261996-11-0606 November 1996 LER 96-011-00:on 961009,potential for Overpressurizing Post Accident Containment Vent Filter Housings Occurred.Caused by Improper Change Mgt.Monitoring Sys Operating Procedures revised.W/961106 Ltr ML17354A3071996-10-22022 October 1996 LER 96-010-00:on 960924,manual Reactor Shutdown Occurred. Caused by Failed Rod Control Sys Regulation Card in 2AC Power cabinet.2AC Power Cabinet DC Power Supplies,Cabling & Connectors checked.W/961022 Ltr ML17353A8711996-08-27027 August 1996 LER 96-009-00:on 960729,failed to Reflect Heavy Load Design Info in Procedural Controls.Caused by Failure to Incorporate 1982 Procedure Changes.Suspended Lifting of Heavy Loads & Took Turbine Bldg Crane OOS.W/960827 Ltr ML17353A7411996-06-18018 June 1996 LER 96-008-00:on 960521,surveillance Method for Testing Emergency Diesel Generators (EDG) Determined Inadequate. Caused by Personnel Error.All Four EDGs Rapid Start Tested & EDG Surveillance Procedures modified.W/960618 Ltr ML17353A7401996-06-18018 June 1996 LER 96-004-02:on 960524,identified Inadequate Surveillance Testing.Caused by Inadequate Surveillance Procedures.Entered Tech Spec Statements,Tested Required Instruments Functions & Revised Plant procedure.W/960618 Ltr ML17353A6901996-05-13013 May 1996 LER 96-004-01:on 960220,identified Potential Tech Spec non-compliance Associated W/Surveillance Testing of AFW Actuation Circuitry on Sg.Caused by Inadequate Surveillance Procedures.Procedures revised.W/960513 Ltr ML17353A6741996-05-0606 May 1996 LER 96-001-00:on 960409,manual Rt Occurred Due to Turbine Governer Control Oil Perturbation.Disassembled & Inspected Governor Valve for Cleanliness & Corrosion products.W/960506 Ltr ML17353A6651996-04-29029 April 1996 LER 96-007-00:on 960329,inadvertent ESF Actuation Occurred During Refueling Outage Due to Cognitive Personnel Error. Personnel Involved Counseled & Integrated Safeguards Test Procedures Being revised.W/960429 Ltr ML17353A6601996-04-25025 April 1996 LER 96-006-00:on 960327,manual Rt Occurred Due to 3C Transformer Lockout & Loss of 3B SG Mfp.Replaced SAM Timer Relay in 3AC16.W/960425 Ltr ML17353A6491996-04-23023 April 1996 LER 96-005-00:on 960326,certain Safety Injection Accumulator Filled Evolutions Resulted in cross-tied Configuration.C/A: Night Order Written & Operations Procedure 3/4-OP-064 revised.W/960423 Ltr ML17353A6051996-03-18018 March 1996 LER 96-003-00:on 960222,two Arpi Inoperable & TS 3.0.3 Entered.Proposed License Amend Submitted to Revise Allowed Misalignment from +/-12 Steps to =/-18 Steps Between Arpi & Dpi at Less than 90% power.W/960318 Ltr ML17353A6041996-03-18018 March 1996 LER 96-004-00:on 960220,surveillance Testing of AFW Actuation Circuitry Was Inadequate.Caused by Inadequate Surveillance Procedures.Tested Untested Portions of Actuation Logic for AFW Automatic Start signal.W/960318 Ltr ML17353A5861996-03-0606 March 1996 LER 96-002-00:on 960209,automatic Turbine Trip/Rt Occurred Due to High SG Level.Caused by Personnel Error.Replaced Both Hinge Pins on B Sgfp Discharge Check valve.W/960306 Ltr ML17353A5761996-03-0101 March 1996 LER 96-001-00:on 960131,intake CWS Flow Rates Found W/ Potential to Be Less than Required by Design Basis.Caused by Influx of Aquatic Grass & Algae Onto Basket Strainers of Icw Flow Path.Mechanically Cleaned strainers.W/960301 Ltr ML17353A4451995-11-0909 November 1995 LER 95-007-00:on 951017,manual Rt Occurred Following Drop of Four Control Rods.Caused by Water Intrusion Into Rod Control Power Cabinet 2BD.Inspected Control Power Cabinet 2BD for Other Water damage.W/951109 Ltr ML17353A4241995-10-12012 October 1995 LER 95-006-00:on 950913,analysis Showed That CCW Exchangers Susceptible to Damage Due to flow-induced Vibration.Ccw Sys Has Been Flow Balanced to Closer tolerances.W/951012 Ltr ML17353A3601995-09-13013 September 1995 LER 95-005-00:on 950818,containment Pressure Testing Procedure Resulted in Inhibiting Both Trains of Containment Pressure from Initiated Esf.Revised Procedure to Require Testing of Each Train separately.W/950913 Ltr ML17353A2951995-07-17017 July 1995 LER 94-005-02:on 941103,both Units Outside Design Basis Due to Design Defect in Safeguards Bus Sequencer Test Logic. Resumed Monthly Manual Testing of Sequencer ML17352B1581995-05-0505 May 1995 LER 95-004-00:on 950407,unit Being Shutdown to Investigate Recurring non-urgent Failure Alarms from Redundant Rod Control Power Supplies.Reactor Manually Tripped.All Four PS-3 Power Supplies replaced.W/950505 Ltr ML17352B1181995-04-0707 April 1995 LER 95-003-00:on 950309,intake Cooling Water Flow Rate Through CCW Heat Exchangers Fell Below Assumed Design Basis. Caused by an Influx of Aquatic Grass & Algae Onto Basket Strainers.Strainers cleaned.W/950407 Ltr ML17352B0701995-03-13013 March 1995 LER 95-002-00:on 950215,inadequate Definition of Loops Filled Resulted in Units in Condition Prohibited by Ts. Issued TS Position Statement to Define Term Loops Filled as Used in TS 6.4.1.1.4.W/950313 Ltr ML17352B0321995-02-0909 February 1995 LER 94-005-01:on 941103,design Defect Found in Safeguards Bus Sequencer Test Logic,Placing Facility Outside Design Basis.Design Mods to Eliminate Software Logic Problems Will Be Implemented During Next Refueling outages.W/950209 Ltr ML17352B0101995-01-20020 January 1995 LER 94-006-00:on 941226,C Main Feedwater Control Valve Failed Closed,Causing Reactor & Turbine Trips.Caused by Loose Screw Terminal Connection.I/P Transducers Replaced W/ New Model W/Different Design Wire connection.W/950120 Ltr ML17352A9511994-12-13013 December 1994 LER 94-006-00:on 941130,Unit 4 Tripped Automatically.Caused by Failure of Flexible Link Connection Between Main Generator B Phase Bus & Associated Isolated Phase Bus Bar. All Bolts on Flexible Link checked.W/941213 Ltr ML17352A8871994-11-10010 November 1994 LER 94-005-00:on 941103,design Defect in Safeguards Bus Sequencer Test Logic Places Both Units Outside Design Basis. Caused by 3A Sequencer Failed to Respond as Expected to Opposite Unit SI signal.W/941110 Ltr ML17352A8851994-11-10010 November 1994 LER 94-004-00:on 941103,Unit 3 Outside Design Basis Due to Two of Three Required Safety Injection Pumps Inoperable. Control Switches for 3A & 3B Safety Injection Pumps Immediately Returned to automatic.W/941110 Ltr ML17352A8421994-10-21021 October 1994 LER 94-004-00:on 940923,Unit 4 Tripped Automatically from Rated Power.Caused by Faulty Regulator Transistor.Faulty Backup Power Supply Replaced & Maint History for Power Supplies reviewed.W/941021 Ltr ML17352A8431994-10-20020 October 1994 LER 94-005-00:on 940924,Unit 4 Manually Tripped.Caused by Manual Actuation.Light Bulb & Socket replaced.W/941020 Ltr ML17352B1671994-08-16016 August 1994 LER 94-003-00:on 940720 & 21,util Discovered That Several Required Valve Stroke Time Surveillances Had Not Been Performed.Caused by Personnel Error.Personnel Reassigned & Procedures and Surveillance Tracking Software Enhanced 1999-07-20
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML20217L9371999-10-20020 October 1999 Safety Evaluation Supporting Licensee Proposed Alternative from Certain Requirements of ASME Code,Section XI for First 10-Yr Interval Request for Relief for Containment Inservice Insp Program ML17355A4471999-09-30030 September 1999 Monthly Operating Repts for Sept 1999 for Turkey Point,Units 3 & 4.With 991008 Ltr ML17355A4121999-08-31031 August 1999 Monthly Operating Repts for Aug 1999 for Turkey Point,Units 3 & 4.With 990909 Ltr ML17355A3981999-07-31031 July 1999 Monthly Operating Repts for July 1999 for Turkey Point,Units 3 & 4.With 990809 Ltr ML17355A3891999-07-20020 July 1999 LER 99-001-00:on 990623,manual Rt from 100% Power Following Multiple Control Rod Drops Was Noted.Caused by Manual Action Taken by Reactor Control Operator.Inspected & Repaired Stationary Gripper Regulating Cards.With 990720 Ltr ML17355A3841999-06-30030 June 1999 Monthly Operating Repts for June 1999 for Turkey Point,Units 3 & 4.With 990713 Ltr ML17355A3681999-06-30030 June 1999 Revised Update to Topical QA Rept, Dtd June 1999 ML17355A3611999-06-30030 June 1999 Refueling Outage ISI Rept. ML17355A3511999-05-31031 May 1999 Monthly Operating Repts for May 1999 for Turkey Point,Units 3 & 4.With 990609 Ltr ML17355A3331999-04-30030 April 1999 Monthly Operating Repts for Apr 1999 for Turkey Point,Units 3 & 4.With 990511 Ltr ML20217B9871999-04-0808 April 1999 Changes,Tests & Experiments Made as Allowed by 10CFR50.59 for Period Covering 971014-990408 ML17355A2881999-04-0505 April 1999 COLR for Turkey Point Unit 4 Cycle 18. ML17355A2911999-03-31031 March 1999 Monthly Operating Repts for Mar 1999 for Turkey Point,Units 3 & 4.With 990414 Ltr ML17355A2551999-02-28028 February 1999 Monthly Operating Repts for Feb 1999 for Turkey Point Nuclear Power Plant,Units 3 & 4.With 990315 Ltr ML17355A2261999-01-31031 January 1999 Monthly Operating Repts for Jan 1999 for Turkey Point,Units 3 & 4.With 990211 Ltr ML17355A2201999-01-20020 January 1999 Refueling Outage ISI Rept. ML17355A1911998-12-31031 December 1998 Monthly Operating Repts for Dec 1998 for Turkey Point,Units 3 & 4.With 990112 Ltr ML18008A0461998-11-30030 November 1998 Monthly Operating Repts for Nov 1998 for Turkey Point,Units 3 & 4.With 981209 Ltr ML17354B1921998-11-18018 November 1998 LER 98-007-00:on 981020,containment Purge Supply,Valve Opened Wider than TS Limit.Caused by Improper Setting of Mechanical Stops.Incorporated Improved Standard Method of Measuring Angular Valve Position Into Sp.With 981118 Ltr ML17354B1891998-11-0909 November 1998 Simulatory Certification Update 2. ML17354B1901998-10-31031 October 1998 Monthly Operating Repts for Oct 1998 for Turkey Point,Units 3 & 4.With 981112 Ltr ML17354B1591998-10-23023 October 1998 COLR for Turkey Point Unit 3 Cycle 17. ML17354B1361998-10-16016 October 1998 LER 98-004-00:on 980921,automatic Reactor Trip Occurred. Caused by Inadequate re-correlation of Intermediate Range Neutron Flux Instrumentation Reactor Trip Bistable. Enhanced Applicable Plant Procedures.With 981016 Ltr ML17354B1311998-09-30030 September 1998 Monthly Operating Repts for Sept 1998 for Turkey Point Unit 3 & 4.With 981012 Ltr ML17354B0971998-09-0909 September 1998 Part 21 Rept Re Possible Machining Defect in Certain One Inch Stainless Steel Swagelok Front Ferrules,Part Number SS-1613-1.Caused by Tubing Slipping Out of Fitting at Three Times Working Pressure of Tubing.Notified Affected Utils ML17354B0981998-08-31031 August 1998 Monthly Operating Repts for Aug 1998 for Turkey Points,Units 3 & 4.With 980915 Ltr ML17354B0771998-07-31031 July 1998 Monthly Operating Repts for July 1998 for Turkey Point,Units 3 & 4.W/980810 Ltr ML17354B0341998-07-15015 July 1998 LER 98-003-00:on 980619,discovered That Auxiliary Feedwater Sys Was Inoperable Due to Inadequate Inservice Testing of Valves.Caused by Misunderstanding of Testing Criteria.Util Revised Procedures & Verified Operability of Valves ML17354B0241998-06-30030 June 1998 Monthly Operating Repts for June 1998 for Turkey Point,Units 3 & 4.W/980709 Ltr ML17354B0171998-06-29029 June 1998 Rev 1 to PTN-FPER-97-013, Evaluation of Turbine Lube Oil Fire. ML17354A9841998-06-18018 June 1998 LER 97-007-01:on 970730,automatic Reactor Trip Occurred Due to Closure of B Msiv.Caused by Failed BFD22S Relay.Six Relays on 3A,3B & 3C MSIVs Were Replaced & Implemented Plant Change to Disable Electronic Trip Function on 3 AFW Pumps ML17354A9741998-06-0909 June 1998 LER 98-002-00:on 980513,discovered Potential LOCA-initiated Electrical Fault Which Places ECCS Outside Design Basis. Caused by Inadequate Review of Effect on non-safety Circuit failures.Re-powered PC-*-600A Relays ML20248F7441998-05-31031 May 1998 Reactor Vessel Working Group,Response to RAI Regarding Reactor Pressure Vessel Integrity ML17354A9711998-05-31031 May 1998 Monthly Operating Repts for Turkey Point,Units 3 & 4. W/980611 Ltr ML17354A9231998-04-30030 April 1998 Monthly Operating Repts for Apr 1998 for Turkey Point,Units 3 & 4.W/980511 Ltr ML17354A8821998-03-31031 March 1998 Monthly Operating Repts for Mar 1998 for Turkey Point,Units 3 & 4.W/980409 Ltr ML17354A8511998-03-24024 March 1998 LER 97-009-01:on 971114,discovered That CR Console Switch for 3B Sgfp Was Not in Start Position.Caused by Inadequate Procedural Guidance.Revised Procedures 3/4-OP-074,informed Personnel of Event & Performed Walkdown of CR ML17354B0001998-03-18018 March 1998 Florida Power & Light Topical Quality Asurance Rept, Dtd June 1998 ML17354A8441998-03-18018 March 1998 LER 98-001-00:on 980216,manual Reactor Trip Occurred Due to Loss of Turbine Control Oil Pressure W/Steam Leak in Auxiliary Feedwater Steam Supply Piping.Auxiliary Governor Maint Instructions Will Be revised.W/980318 Ltr ML17354A8311998-02-28028 February 1998 Monthly Operating Repts for Feb 1998 for Turkey Point,Units 3 & 4.W/980311 Ltr ML17354A7871998-01-31031 January 1998 Monthly Operating Repts for Jan 1998 for Turkey Point,Units 3 & 4.W/980209 Ltr ML17354A7581997-12-31031 December 1997 Monthly Operating Repts for Dec 1997 for Turkey Point,Unit 3 & 4.W/980112 Ltr ML17354A7361997-12-12012 December 1997 LER 97-009-01:on 971114,identified That CR Console Switch for 3B SG Feedwater Pump Was Not in Start Position.Caused by Inadequate Procedural Guidance.Procedures 3/4-OP-074,SGFP Were revised.W/971212 Ltr ML17354A7381997-11-30030 November 1997 Monthly Operating Repts for Nov 1997 for Turkey Point,Units 3 & 4.W/971215 Ltr ML17354A7211997-10-31031 October 1997 Monthly Operating Repts for Oct 1997 for Turkey Point,Units 3 & 4.W/971114 Ltr ML17354A7491997-10-13013 October 1997 SG Insp Rept. ML17354A8851997-10-13013 October 1997 FPL Units 3 & 4 Changes,Tests & Experiments Made as Allowed by 10CFR50.59 for Period Covering 960408-971013. ML17354A6801997-10-0808 October 1997 LER 97-008-00:on 970909,containment Sump Debris Screens Outside Design Basis Due to Stress Damage Was Discovered. Caused by Inadequate Procedural Guidance & Personnel Error. Discrepancies Found on Screens corrected.W/971008 Ltr ML17354A6791997-10-0606 October 1997 COLR Unit 4 Cycle 17, for Turkey Point ML17354A6811997-09-30030 September 1997 Monthly Operating Repts for Sept 1997 for Turkey Point,Units 3 & 4.W/971009 Ltr 1999-09-30
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I REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)ACCESSION NBR:9201090114 DOC.DATE: 91/12/18 NOTARIZED:
NO DOCKET FACIL:50-250 Turkey Point Plant, Unit 3, Florida Power and Light C 05000250 AUTH.NAME AUTHOR AFFILIATION POWELL,D.R; Florida Power 6 Light Co.PLUNKETT,T.F.
Florida Power&Light Co.RECIP.NAME
-RECIPIENT AFFILIATION
SUBJECT:
LER 91-011-00:on 911011,Appendix R Safe Shutdown Analysis design inadequacy identified due to failure to recognize potential for spurious actuation of auxiliary relay.Manual Action List in Safe Shutdown Analysis revised.W/911218 ltr.DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR ENCL)SIZE'TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.NOTES'RECIPIENT ID CODE/NAME PD2-2 LA AULUCK,R INTERNAL: ACNW AEOD/DS P/TPAB NRR/DET/ECMB 9H NRR/DLPQ/LHFB10 NRR/DOEA/OEAB NRR/DST/SELB 8D'PLB8D1 F112 FILE 01 EXTERNAL EGGG BRYCE i J~H NRC PDR" NSIC POORE,W.COPIES LTTR ENCL 1 1 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1" 3 3 1 1 1 1 RECIPIENT ID CODE/NAME PD2-2 PD AEOD/DOA AEOD/ROAB/DSP NRR/DET/EMEB 7E NRR/DLPQ/LPEB10 NRR/DREP/PRPB11 NRR/DST/SICB8H3 NRR/DST/SRXB 8E RES/DSIR/EIB L ST LOBBY WARD NSIC MURPHY,G.A NUDOCS FULL TXT COPIES LTTR ENCL 1'1 1 2 2 1 1 1'1 2 2 1'1 1 1 1 1 1 1 1 1 1 1 D D D NOTE TO ALL"RIDS" RECIPIENTS:
D D PLEASE HELP US TO REDUCE WASTE!CONTACT THE DOCUMENT CONTROL DESK, ROOM PI-37 (EXT.20079)TO ELIMINATE YOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 31 ENCL 31 P..Box 029100, Miami, FL, 33102-9100 APL~Pi'18m>L-91-341 10 CFR 50.73 U.S.Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C.20555 Gentlemen:
Re: Turkey Point Units 3 Docket No.50-250 Reportable Event: 91-011-00 Date of Event: October 11, 1991 10 CFR 50 A endix R Safe Shutdown Anal sis Desi n Inade uac The attached Licensee Event Report 250-91-011-00 is being provided in accordance with the requirements of 10 CFR 50.73(a)(2)(ii) to provide notification of the subject event.Very truly yours, T.F.Plunkett.Vice President Turkey Point Nuclear I TFP/CLM/clm Attachment cc: Stewart D.Ebneter, Regional Administrator, Region II, USNRC Senior Resident Inspector, USNRC, Turkey Point Plant 0.r r)~.1>3 v4 AOOCK Qr 1(.)oi.)':.red F Lr:=.'n FPL Group company FACILITY NAME ll)LICENSEE'EVENT"REPORT'LER)
DOCKET NUMBER{2)PAGE l3)TITLE l4)TURKEY POINT UNIT 3 05000250'oF 4 10 CFR 50 A endix R Safe Shutdown Anal sis Design Inade uac EVENT DATE l5)LER NUMBER 6 RPT DATE l7)OTHER FACILITIES INV.<8)MON DAY YR eSEQ I Rl MON DAY YR-FACILITY NAMES DOCKET t lS)10 91 91'011 00 12 18 91 TURKEY"POINT UNIT'4 05000251 OPERATING MODE l>)1 PO'HER LEVEL l10)45 10 CFR'0.73 a'ii L'ICENSFE CONTACT FOR THIS LER (12)David R.Powell, Licensing Superintendent TELEPHONE NUMBER 305-246-6559 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT l13)CAUSE SYSTEM COMPONENT NPRDS?CAUSE COMPONFNT MANUFACTURER NPRDS?SUPPLEMENTAL REPORT EXPECTED,l1,4)
WO,gl~;."-YES Q l1f yes, cceylete EXPECTED SUBMISSION DATE)EXPECTED QUBMIS S ION~, DATE l15)MONTH DAY ABSTRACT l16)On October 11, 1991, at: 0700"EDT,-,Florida-.;Power;,and Light'identified an Appendix R Safe Shutdown Analysis design inadequacy at Turkey Point.Originally considered
'not'eportable, further review resulted in the decision to report'the condition'as one n'ot'covered by procedures..As described in the Turkey Point Appendix R,Alternate Shutdown analysis, our design and procedures are required to be able to shut down the plant for a fire which'.may'-,occur in the control room or the=cable spreading room.Additionally, a.loss of offsite power is assumed to occur.The procedure for control.room evacuation directs the removal of power from the safeguards relay'racks,,but"this'ction may.not prevent a spurious.short from occurring on,the:output side of a safeguards relay.The resulting spurious actuation of a, safeguards auxiliary relay, coupled with disabling of the Emergency Diesel Generator (EDG)lo'ad sequencer,:will result in.4zipping of.the ZDG output breaker..This scenario applies to the 3B;and the 4B"EDGs.The Manual Action List in the Safe Shutdown Analysis, and the Off-Normal Operating Procedure" for control room evacuation, have both'"been
- revised to require the removal-of f'uses which.will prevent the.spurious.actuation of the.auxiliary relay.
LICENSEE QENT REPORT (LER)TEXT QVJIEUATIOE FACILITY NAME DOCKET NUMBER TURKEY POINT UNIT 3 05000250 LER NUMBER 91-011-00 PAGE NO.02 OF 04 EVENT DESCRIPTION On October 11, 1991, at 0700 EDT, with Unit 3 in Mode 1 at 45 percent power and Unit 4 in Mode 6 (Refueling), a system engineer (non-licensed utility personnel) identified a potential design inadequacy with the Turkey Point 10 CFR 50 Appendix R Safe Shutdown analysis.A Nonconformance Report (NCR)was generated to determine if the postulated spurious scenario was valid, and, if so, what corrective actions were necessary.
Two suggested corrective actions were offered;one hardware modification, and one procedure enhancement.
The NCR disposition stated that the postulated scenario was valid, and provided two corrective actions, both procedural.
The corrective actions were implemented by the time the NCR disposition was approved.In.addition, the disposition stated that there was no plant operability concern resulting from the NCR.On that basis, the condition was originally deemed to be not reportable; In response to concerns raised by the resident inspector, the 10 CFR 50 Appendix R requirements, the Turkey Point Safe Shutdown Analysis, and the facility Upgraded Final Safety Analysis Report were further examined.On November 21, 1991, at 1438, the condition was determined to be one not covered by the plant's operating and emergency procedures at the time the NCR was generated, and therefore reportable under 10 CFR 50.72(b)(1), and under 10 CFR 50.73 (a)(2).10 CFR 50 Appendix R Alternate Shutdown criteria require that design and procedures be able to shut down the plant, for a fire which may occur in the control room.Additionally, a loss of offsite power is assumed to occur.The following discussion describes the relays and components for Unit 3 Train B.The scenario described also applies to Unit 4 Train B.The B Trains are the"protected" trains for the Appendix R Safe Shutdown analysis.Accoz'ding to Turkey Point's current Safe Shutdown Analysis, circuit 3E24Z is protected by removing power from the Safeguards
[JE]relay[RLY]racks.This is reflected in procedure O-ONOP-105, Control Room Evacuation, in Attachment 7, Step 6.This action will not prevent a possible spurious actuation from occurring on the output side of the safeguards relays.One of theses relays (9524/3A)is associated with the 3B EDG.A spurious short of relay SI23X contacts 2-6'ill result in actuation of relay 9524/3A.This relay actuation, coupled with disabling of the EDG load sequencer per O-ONOP-105, will result in tripping of the 3B EDG output breaker[52].The condition was reported pursuant to 10 CFR 50.72 (b)(1)(ii)at 1530 on November 21, 1991.
LICENSEE ENT REPORT (LER)TEXT tlTINUATION FACILITY NAME TURKEY POINT UNIT 3 DOCKET NUMBER 05000250 LER NOMBER 91-011-00 PAGE NO: 03 OF 04 II.EVENT CAUSE The cause of this condition was design inadequacy.
The Appendix R Safe Shutdown Analysis design'eview for Plant Change/Modification 87-264 failed to recognize the potential for this possible spurious scenario;therefore, mitigating manual actions were not included in the Safe Shutdown Analysis Manual Action List.III.EIGHT SAFETY ANALYSIS The EDG output breaker circuitry has been designed to trip the breaker upon receipt of a Safety Injection (SI)signal.If an SI signal is received while the EDG is responding to a Loss of Offsite Power (LOOP), or during periodic testing with the EDG paralleled to the grid, the EDG output breaker trips automatically, without tripping the EDG.The objective of this feature is to re-strip the busses and allow loading of the Safeguards equipment, for the"LOOP followed by SI" event, and to separate the EDG from the grid, for the"parallel testing followed by SI" event.Although the postulated scenario is a valid spurious actuation scenario, there are at least two concurrent events required to trip the EDG output breaker;(1)fire in the control room safeguards rack, and (2)failure of the 12 conductor cable 3E24Z/B 3C23B-3QR45 by shorting conductors 1 and Pl.The probability of this scenario exists only during an Alternate Shutdown condition, and even then is considered highly unlikely.The design basis for this Appendix R fire scenario renders the EDG output breaker unusable;however, the design basis also allows the use of manual action to achieve and maintain hot standby conditions.
Any of several manual actions, such as removal of the fuses on the trip portion of the EDG breaker circuit, tripping of the SI auxiliary relays breaker, or removal of the fuses that power the SI auxiliary relays, would allow closure of the EDG output breaker.Since the postulated scenario would result in obvious symptoms, e.g., loss of lighting, operators would be reasonably expected to recognize the symptoms and take manual actions.In addition, the control room is manned around the clock, and fire extinguishers are available in the control room.These mitigating factors provide added insurance against the postulated scenario.Thus the health and safety of the public was not materially affected.Nevertheless, the choice.of action is important, and therefore the optimum corrective action warrants inclusion in the control room evacuation procedure.
Removal of the fuses that power the SI auxiliary relays, including 9524/3A, does not affect any equipment or functions that are required for Alternate Shutdown, and hence is considered the optimum manual action.
I ICENSEEEMT REPORT (LER)TEXT QFZINUATION FACILITY NAME DOCKET NOMBER TURKEY POINT UNIT 3 05000250 LER NUMBER>>PAGE No.91-011-00 04 OF 04 IV.CORRECTXVE ACTIONS Procedure 0-ONOP-105 was revised with an On The Spot Change (OTSC)on October 11, 1991, to.include steps to remove fuses FU-1(+)and FU-1(-), thereby de-energizing the SI auxiliary relays during control room evacuation.
The OTSC was reviewed and approved by.the E'lant.Nuclear Safety.,Committee on October 15, 1991.,2.'-,.Change.Recpxest Notice CRN-, M-5490~as.:issued to correct the'-.-:Appendix R Safe Shutdown.Analysis Manual..Action List by adding steps to-pull fuses ZV-1(+)and FU-1(-).The CRN was approved on Oct.ober'll,'1991.3;"'The feeder.cableroutingto the SI auxi'liary relays has also been reviewed to verify that other possible cable to cable failures" will.not result'n the energization of the SI-, auxiliary,.relays.
W'll f 0~v~~f'%~V'.ADDXTXONAX, XNFORMATXON
- 1'P%>t9 a%~Licensee Event Report 50-250/89-09 described another Appendix R design izadequacy"," involving the operation of, valves supplying water-:.to-.the:suction.';of the-;charging imps.:
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