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Category:LICENSEE EVENT REPORT (SEE ALSO AO
MONTHYEARML18066A6271999-09-0202 September 1999 LER 98-011-01:on 981217,inadequate Lube Oil Collection Sys for Primary Coolant Pumps Was Noted.Caused by Design Change Not Containing Appropriate Level of Rigor.Exemption from 10CFR50,App R Was Requested.With 990902 Ltr ML18066A6221999-08-20020 August 1999 LER 99-002-00:on 990722,TS Surveillance Was Not Completed within Specified Frequency.Caused by Failure to Incorporate Revised Frequency Into Surveillance Schedule in Timely Manner.Verified Implementation.With 990820 Ltr ML18066A3781999-01-20020 January 1999 LER 98-013-00:on 981222,safeguards Transfer Tap Changer Failure Caused Inadvertant DG Start.Caused by Failed Motor Contactor.Contactor Was Replaced.With 990120 Ltr ML18068A4851998-10-29029 October 1998 LER 97-011-01:on 971012,starting of Primary Coolant Pump with SG Temps Greater than Cold Leg Temps Occurred.Caused by Inadequate Procedures & Operator Decision.Sop Used for Starting Primary Coolant Pump Enhanced ML18066A2831998-08-18018 August 1998 LER 98-010-00:on 980721,reactor Manually Tripped.Caused by Failure of Coupling Which Drives Feedwater Pump Main Lube Oil Pump.Main Lube Oil Pump Coupling & Associated Components Replaced & Satisfactorily Tested ML18066A2261998-06-30030 June 1998 LER 98-009-00:on 980531,small Pinhole Leak Found on One of Welds,During Leak Test Following Replacement of Pcs Sample Isolation Valves.Caused by Welder Error.Leaking Welds Repaired ML18066A1781998-06-0909 June 1998 LER 98-008-00:on 980511,noted That Procedure Did Not Fully Satisfy Requirement to Test High Startup Rate Trip Function. Caused by Misunderstanding of Testing Requirements.Revised TS Surveillance Test Procedure & Reviewed Other Procedures ML18065B2451998-05-13013 May 1998 LER 98-007-00:on 980413,HPIS Sys Was Noted Inoperable During TS Surveillance Test.Caused by Performance of Flawed Procedure.Operators & Engineers Will Be Trained to Improve Operational Decision Making Through Resources & Knowledge ML18065B1151997-12-0909 December 1997 LER 97-013-00:on 971110,failure to Closure Test Two Check Valves Resulted in Violation of TS 6.5.7 Occurred.Caused by Close Function for Check Valves.Check Valves Tested to Confirm Proper Closure Capability ML18067A7751997-11-11011 November 1997 LER 97-011-00:on 971012,primary Coolant Pump Was Started W/Sg Temperatures Greater than Cold Leg Temperature.Caused by Inadequate Procedures & Operator Decision Making.Critique of Event Conducted W/Operators Involved ML18067A7581997-10-30030 October 1997 LER 97-010-00:on 970930,determined That Inadequacy in App R Analysis Resulted in Condition Outside Design Basis of Plant.Caused by Missing Cable in Circuit & Raceway Schedule. Developed New Evaluation Re ASD Valves Validation ML18067A7461997-10-23023 October 1997 LER 97-009-00:on 970923,discovered Procedure Weakness Re Implementation of App R Shutdown Methodology.Caused by Human Error.Revised Off-Normal Procedure ONP-25.2, Alternate Safe Shutdown Procedure. ML18067A7191997-10-10010 October 1997 LER 97-008-00:on 970912,spurious Valve Operation Could Result in Loss of Shutdown Capabilities Per 10CFR50,App R, Section Iii.L,Was Discovered.Caused by Failure to Validate Info from App R.Design Bases for SW Backup Reviewed ML18067A6951997-09-24024 September 1997 LER 97-007-00:on 970826,discovered Inadequate Testing of DG Sequencer Control Relay Contacts.Caused by Oversight on Part of Personnel Involved in Installation of Facility Change FC-800.Tested 106D-1/XL & 106D-2/XL Relay Contacts ML18067A5651997-06-0303 June 1997 LER 96-013-01:on 961115,DC Breaker Failed During Testing for as-found Trip Setting.Failure Caused by Oversight within Preventive Maint Program.Breaker Was Replaced & Tested ML18067A5461997-05-12012 May 1997 LER 97-006-00:on 970412,overtime Limits Were Exceeded for Radiation Protection Technicians.Caused by Inadequate Design,Review & Proper Verifications of Overtime Work Schedule.Communicate Overtime Limitation Responsibilities ML18067A4431997-03-24024 March 1997 LER 97-004-00:on 970221,trip of High Pressure Safety Injection Pump Occurred While Filling Safety Injection Tank Resulting in TS Violation.Caused by Particle Lodged Between Surface of Indication disk.Y-phase Relay Was OOS ML18067A4391997-03-21021 March 1997 LER 97-005-00:on 961220,operation of Plant Outside Design Basis Occurred Due to an Unacceptable Repair on Main Steam Isolation Valves.Pipe Plugs Permanently Repaired ML18067A4401997-03-21021 March 1997 LER 97-003-00:on 961101,four Piping Lines Were Determined to Be Potentially Susceptible to Pressurization Due to Containment Temperature Increase During an Accident.Cac Discharge Piping Will Be verified.W/970321 Ltr ML18066A8931997-02-21021 February 1997 LER 97-002-00:on 970123,failure to Meet TSs 4.5.2d(1)(b) for Testing of Emergency Escape Airlock Occurred.Caused by Missed Surveillance.Emergency Escape Air Lock Testing Was Completed & Declared operable.W/970221 Ltr ML18066A8751997-02-0505 February 1997 LER 97-001-00:on 970106,TAVE Temp Dropped Below Minimum Temp for Criticality.Caused by Control Rod Withdrawal Rate to Increase Power Not Sufficient to Match Increase in Steam. Turbine Bypass Valve Actuator repaired.W/970205 Ltr ML18066A8041996-12-23023 December 1996 LER 96-014-00:on 961124,class 1E Raychem Cable Splices Were Installed Incorrectly.Caused by Incorrectly Made Electrical Splices.Total of 270 Splices Have Been Replaced within Containment ML18066A7831996-12-16016 December 1996 LER 96-013-00:on 961115,DC Breaker Failure During Testing for as-found Trip Setting Occurred.Cause Under Investigation.All molded-case Circuit Breakers in DC Distribution Panels Were Replaced ML18065A9951996-10-0404 October 1996 LER 96-002-01:on 960116,initiated TS Required Shutdown Due to Safeguards Cable Fault.Both Sets (Six Cables) of Cables Were Replaced & Installed Through Turbine Generator Bldg ML18065A9171996-09-0909 September 1996 LER 95-012-00:on 960809,TS Violation Occurred,Due to No Senior Reactor Operator in Cr.Caused by Extensive Remodeling.Cr Remodeling completed.W/960909 Ltr ML18065A8961996-08-29029 August 1996 LER 96-011-00:on 960730,CR Continuous Air Monitor Alarm Setpoint Improperly Established.Caused by Failure to Utilize Mod Process in 1988 Leading to Failure to Properly Select & Calibrate Instruments ML18065A8811996-08-20020 August 1996 LER 96-005-01:on 960207,determined Fuse on Main Supply to Two Safety Related DC Panels & Panel Branch Circuit Breakers Not Properly Coordinated.Caused by Lack of Thorough Associated Circuits Analysis.Supply Fuse to Panels Replaced ML18065A8741996-08-16016 August 1996 LER 96-010-00:on 960717,high Pressure Safety Injection Pump Tripped While Filling Safety Injection Tank.Caused by Faulty 150/151Y-207 Time Overcurrent Relay.All Similar Relays in Time Overcurrent Application Have Been Inspected ML18065A8651996-08-12012 August 1996 LER 96-009-00:on 960712,identified Penetration Seal Deficiency on Fire Barriers Caused by Failure to Perform & Document Comprehensive Fire Barrier Evaluation.Developed Basis document.W/960812 Ltr ML18065A8601996-08-0202 August 1996 LER 96-006-01 on 960207,discovered Limits of Design Analysis Could Have Been Violated.Subsequent Tests & Analyses Facility Did Not Exceed Basis.Operating Procedures Have Been Revised to Treat 2530 Megawatts Limit as Absolute Limit ML18065A8321996-08-0101 August 1996 LER 96-003-01:on 960115,alternate Shutdown Panel Inverter Resulted in Unavailability of Panel.Replaced Defective Inverter Alarm Logic Board ML18065A7691996-06-12012 June 1996 LER 96-008-00:on 960513,fire Door Not Maintained Open in Accordance W/Design Basis.Cause Under Investigation. Engineering Evaluation Performed & Revised Documents, Surveillance & Test procedures.W/960612 Ltr ML18065A6901996-05-0101 May 1996 LER 95-001-01:on 950302,malfunction of Left Channel DBA Sequencer Resulted in Inadvertent Actuation of Left Channel Safeguards Equipment.Replaced microprocessor.W/960501 Ltr ML18065A6681996-04-22022 April 1996 LER 96-007-00:on 960321,inadequate Emergency Lighting & Ventilation in post-fire Safe Shutdown Areas.Caused by App R Program Documentation Insufficient to Demonstrate Regulatory Compliance.Lighting modified.W/960422 Ltr ML18065A5721996-03-11011 March 1996 LER 96-006-00:on 960207,average Reactor Power Level Exceeded License Limit Due to Insufficient Procedural Guidance. GOP-12 Revised to Treat 2,530 Mwt Limit as Absolute Limit Requiring Immediate Corrective Action If Exceeded ML18065A5261996-03-0101 March 1996 LER 96-005-00:on 960202,fuse on Main Supply to Two SR DC Panels & Panel Branch Circuit Breakers Not Properly Coordinated.Caused by Inadequate Electrical/App R Design Review.Implemented Hourly Fire tours.W/960301 Ltr ML18065A5111996-02-19019 February 1996 LER 94-012-02:on 940427,determined That Internal Ground in Thermal Margin Monitor Causes Nonconformance W/Rps Design Basis.Incorporated RPS Failure Modes & Effects Analysis in Plant DBD.W/960219 Ltr ML18065A5061996-02-19019 February 1996 LER 96-004-00:on 960118,SIS Disabled W/Primary Coolant Sys Greater than 300 F.Caused by Personnel Error.Permanent Maint Procedure to Disable/Enable SIS Actuation on Low Pressurizer Pressure Will Be Revised to Align W/Ts ML18065A5021996-02-15015 February 1996 LER 96-003-00:on 960115,technicians Found Low Voltage cut- Off for Alternate Shutdown Panel Inverter Set That Resulted in Unavailability of Panel.Caused by Inadequate Post Mod. Readjusted Set Point to Minimum setting.W/960215 Ltr ML18065A4581996-01-31031 January 1996 LER 96-001-00:on 960103,failed to Test Duplicate Equipment. Caused by STS No Longer Containing Requirement for cross- Train Testing of Duplicate Components.Will Submit Request to Delete Subj Requirements from TS.W/960131 Ltr ML18065A4421996-01-19019 January 1996 LER 95-016-00:on 951226,did Not Analyze Primary Coolant Samples within 72 H.Caused by Belief Acceptability to Save Pcs Samples for Choride Analysis Past 72 H.Counseled Chemistry Supervision.W/960119 Ltr ML18065A4041996-01-15015 January 1996 LER 95-014-00:on 950119,PCP Oil Collection Deficiencies Created by FC-860 Piping Mod.Caused by Inadequate DBD for Sys & Lack of Review by Experienced Fire Protection Personnel.Updated Design Basis documentation.W/960115 Ltr ML18065A3291995-12-0404 December 1995 LER 95-013-00:on 951103,circuit Fuse Coordination Deficiency Which Affects App R Safe Shutdown Equipment Noted.Design of Fuse Coordination in Potential Transformer Circuits Will Be Evaluated & Modified as required.W/951204 Ltr ML18065A2361995-11-0202 November 1995 LER 95-012-00:on 950701,discovered Unqualified Electrical Connection in Containment SW Outlet Valve Controller.Caused by Failure of Assigned Engineers to Available Info.Replaced Wire Nuts W/Inline Butt connections.W/951102 Ltr ML18065A2051995-10-20020 October 1995 LER 95-008-01:on 950728,discovered That None of Four Containment High Pressure Channels Would Initiate Reactor Trip Due to Programmatic Deficiencies.Administrative Procedure (AP) 9.44,AP 9.45 & AP 10.44 Will Be Revised ML18065A0841995-09-18018 September 1995 LER 95-011-00:on 950817,CR 40 Withdrawal Occurred When Given Insertion Signal Due to skill-based Error in Crimping & Removing Foreign Matl from CRDM Motor Connection Box.Crd Package replaced.W/950918 Ltr ML18065A0681995-09-14014 September 1995 LER 95-010-00:on 950815,ESFA Resulted in Manual Rt Following Isolation of Pcs.Replaced Failed Instrument Line ML18065A0651995-09-0808 September 1995 LER 95-009-00:on 950728,discovered Lack of Procedural Guidance for Pump Repair Following Fire.Proposed Use of Power Supply Breaker Did Not Adequately Address Effect of Loss of Control Power.Performed Independent Assessment ML18064A8781995-08-28028 August 1995 LER 95-008-00:on 950728,discovered During Design Change Testing That None of Four Containment High Pressure Channels Would Initiate Rt.Caused by Programmatic Deficiencies. Reviewed Selected Tests & Mods from Recent Refueling Outage ML18064A8831995-08-21021 August 1995 LER 95-007-00:on 950720,discovered That 12 Instrument Loops Had V-bolted Type Qualified Cable Splices Connected to Wires W/Exposed Kapton Insulation.Caused by Human Error.All V- Bolted Splices Replaced w/in-line design.W/950821 Ltr 1999-09-02
[Table view] Category:RO)
MONTHYEARML18066A6271999-09-0202 September 1999 LER 98-011-01:on 981217,inadequate Lube Oil Collection Sys for Primary Coolant Pumps Was Noted.Caused by Design Change Not Containing Appropriate Level of Rigor.Exemption from 10CFR50,App R Was Requested.With 990902 Ltr ML18066A6221999-08-20020 August 1999 LER 99-002-00:on 990722,TS Surveillance Was Not Completed within Specified Frequency.Caused by Failure to Incorporate Revised Frequency Into Surveillance Schedule in Timely Manner.Verified Implementation.With 990820 Ltr ML18066A3781999-01-20020 January 1999 LER 98-013-00:on 981222,safeguards Transfer Tap Changer Failure Caused Inadvertant DG Start.Caused by Failed Motor Contactor.Contactor Was Replaced.With 990120 Ltr ML18068A4851998-10-29029 October 1998 LER 97-011-01:on 971012,starting of Primary Coolant Pump with SG Temps Greater than Cold Leg Temps Occurred.Caused by Inadequate Procedures & Operator Decision.Sop Used for Starting Primary Coolant Pump Enhanced ML18066A2831998-08-18018 August 1998 LER 98-010-00:on 980721,reactor Manually Tripped.Caused by Failure of Coupling Which Drives Feedwater Pump Main Lube Oil Pump.Main Lube Oil Pump Coupling & Associated Components Replaced & Satisfactorily Tested ML18066A2261998-06-30030 June 1998 LER 98-009-00:on 980531,small Pinhole Leak Found on One of Welds,During Leak Test Following Replacement of Pcs Sample Isolation Valves.Caused by Welder Error.Leaking Welds Repaired ML18066A1781998-06-0909 June 1998 LER 98-008-00:on 980511,noted That Procedure Did Not Fully Satisfy Requirement to Test High Startup Rate Trip Function. Caused by Misunderstanding of Testing Requirements.Revised TS Surveillance Test Procedure & Reviewed Other Procedures ML18065B2451998-05-13013 May 1998 LER 98-007-00:on 980413,HPIS Sys Was Noted Inoperable During TS Surveillance Test.Caused by Performance of Flawed Procedure.Operators & Engineers Will Be Trained to Improve Operational Decision Making Through Resources & Knowledge ML18065B1151997-12-0909 December 1997 LER 97-013-00:on 971110,failure to Closure Test Two Check Valves Resulted in Violation of TS 6.5.7 Occurred.Caused by Close Function for Check Valves.Check Valves Tested to Confirm Proper Closure Capability ML18067A7751997-11-11011 November 1997 LER 97-011-00:on 971012,primary Coolant Pump Was Started W/Sg Temperatures Greater than Cold Leg Temperature.Caused by Inadequate Procedures & Operator Decision Making.Critique of Event Conducted W/Operators Involved ML18067A7581997-10-30030 October 1997 LER 97-010-00:on 970930,determined That Inadequacy in App R Analysis Resulted in Condition Outside Design Basis of Plant.Caused by Missing Cable in Circuit & Raceway Schedule. Developed New Evaluation Re ASD Valves Validation ML18067A7461997-10-23023 October 1997 LER 97-009-00:on 970923,discovered Procedure Weakness Re Implementation of App R Shutdown Methodology.Caused by Human Error.Revised Off-Normal Procedure ONP-25.2, Alternate Safe Shutdown Procedure. ML18067A7191997-10-10010 October 1997 LER 97-008-00:on 970912,spurious Valve Operation Could Result in Loss of Shutdown Capabilities Per 10CFR50,App R, Section Iii.L,Was Discovered.Caused by Failure to Validate Info from App R.Design Bases for SW Backup Reviewed ML18067A6951997-09-24024 September 1997 LER 97-007-00:on 970826,discovered Inadequate Testing of DG Sequencer Control Relay Contacts.Caused by Oversight on Part of Personnel Involved in Installation of Facility Change FC-800.Tested 106D-1/XL & 106D-2/XL Relay Contacts ML18067A5651997-06-0303 June 1997 LER 96-013-01:on 961115,DC Breaker Failed During Testing for as-found Trip Setting.Failure Caused by Oversight within Preventive Maint Program.Breaker Was Replaced & Tested ML18067A5461997-05-12012 May 1997 LER 97-006-00:on 970412,overtime Limits Were Exceeded for Radiation Protection Technicians.Caused by Inadequate Design,Review & Proper Verifications of Overtime Work Schedule.Communicate Overtime Limitation Responsibilities ML18067A4431997-03-24024 March 1997 LER 97-004-00:on 970221,trip of High Pressure Safety Injection Pump Occurred While Filling Safety Injection Tank Resulting in TS Violation.Caused by Particle Lodged Between Surface of Indication disk.Y-phase Relay Was OOS ML18067A4391997-03-21021 March 1997 LER 97-005-00:on 961220,operation of Plant Outside Design Basis Occurred Due to an Unacceptable Repair on Main Steam Isolation Valves.Pipe Plugs Permanently Repaired ML18067A4401997-03-21021 March 1997 LER 97-003-00:on 961101,four Piping Lines Were Determined to Be Potentially Susceptible to Pressurization Due to Containment Temperature Increase During an Accident.Cac Discharge Piping Will Be verified.W/970321 Ltr ML18066A8931997-02-21021 February 1997 LER 97-002-00:on 970123,failure to Meet TSs 4.5.2d(1)(b) for Testing of Emergency Escape Airlock Occurred.Caused by Missed Surveillance.Emergency Escape Air Lock Testing Was Completed & Declared operable.W/970221 Ltr ML18066A8751997-02-0505 February 1997 LER 97-001-00:on 970106,TAVE Temp Dropped Below Minimum Temp for Criticality.Caused by Control Rod Withdrawal Rate to Increase Power Not Sufficient to Match Increase in Steam. Turbine Bypass Valve Actuator repaired.W/970205 Ltr ML18066A8041996-12-23023 December 1996 LER 96-014-00:on 961124,class 1E Raychem Cable Splices Were Installed Incorrectly.Caused by Incorrectly Made Electrical Splices.Total of 270 Splices Have Been Replaced within Containment ML18066A7831996-12-16016 December 1996 LER 96-013-00:on 961115,DC Breaker Failure During Testing for as-found Trip Setting Occurred.Cause Under Investigation.All molded-case Circuit Breakers in DC Distribution Panels Were Replaced ML18065A9951996-10-0404 October 1996 LER 96-002-01:on 960116,initiated TS Required Shutdown Due to Safeguards Cable Fault.Both Sets (Six Cables) of Cables Were Replaced & Installed Through Turbine Generator Bldg ML18065A9171996-09-0909 September 1996 LER 95-012-00:on 960809,TS Violation Occurred,Due to No Senior Reactor Operator in Cr.Caused by Extensive Remodeling.Cr Remodeling completed.W/960909 Ltr ML18065A8961996-08-29029 August 1996 LER 96-011-00:on 960730,CR Continuous Air Monitor Alarm Setpoint Improperly Established.Caused by Failure to Utilize Mod Process in 1988 Leading to Failure to Properly Select & Calibrate Instruments ML18065A8811996-08-20020 August 1996 LER 96-005-01:on 960207,determined Fuse on Main Supply to Two Safety Related DC Panels & Panel Branch Circuit Breakers Not Properly Coordinated.Caused by Lack of Thorough Associated Circuits Analysis.Supply Fuse to Panels Replaced ML18065A8741996-08-16016 August 1996 LER 96-010-00:on 960717,high Pressure Safety Injection Pump Tripped While Filling Safety Injection Tank.Caused by Faulty 150/151Y-207 Time Overcurrent Relay.All Similar Relays in Time Overcurrent Application Have Been Inspected ML18065A8651996-08-12012 August 1996 LER 96-009-00:on 960712,identified Penetration Seal Deficiency on Fire Barriers Caused by Failure to Perform & Document Comprehensive Fire Barrier Evaluation.Developed Basis document.W/960812 Ltr ML18065A8601996-08-0202 August 1996 LER 96-006-01 on 960207,discovered Limits of Design Analysis Could Have Been Violated.Subsequent Tests & Analyses Facility Did Not Exceed Basis.Operating Procedures Have Been Revised to Treat 2530 Megawatts Limit as Absolute Limit ML18065A8321996-08-0101 August 1996 LER 96-003-01:on 960115,alternate Shutdown Panel Inverter Resulted in Unavailability of Panel.Replaced Defective Inverter Alarm Logic Board ML18065A7691996-06-12012 June 1996 LER 96-008-00:on 960513,fire Door Not Maintained Open in Accordance W/Design Basis.Cause Under Investigation. Engineering Evaluation Performed & Revised Documents, Surveillance & Test procedures.W/960612 Ltr ML18065A6901996-05-0101 May 1996 LER 95-001-01:on 950302,malfunction of Left Channel DBA Sequencer Resulted in Inadvertent Actuation of Left Channel Safeguards Equipment.Replaced microprocessor.W/960501 Ltr ML18065A6681996-04-22022 April 1996 LER 96-007-00:on 960321,inadequate Emergency Lighting & Ventilation in post-fire Safe Shutdown Areas.Caused by App R Program Documentation Insufficient to Demonstrate Regulatory Compliance.Lighting modified.W/960422 Ltr ML18065A5721996-03-11011 March 1996 LER 96-006-00:on 960207,average Reactor Power Level Exceeded License Limit Due to Insufficient Procedural Guidance. GOP-12 Revised to Treat 2,530 Mwt Limit as Absolute Limit Requiring Immediate Corrective Action If Exceeded ML18065A5261996-03-0101 March 1996 LER 96-005-00:on 960202,fuse on Main Supply to Two SR DC Panels & Panel Branch Circuit Breakers Not Properly Coordinated.Caused by Inadequate Electrical/App R Design Review.Implemented Hourly Fire tours.W/960301 Ltr ML18065A5111996-02-19019 February 1996 LER 94-012-02:on 940427,determined That Internal Ground in Thermal Margin Monitor Causes Nonconformance W/Rps Design Basis.Incorporated RPS Failure Modes & Effects Analysis in Plant DBD.W/960219 Ltr ML18065A5061996-02-19019 February 1996 LER 96-004-00:on 960118,SIS Disabled W/Primary Coolant Sys Greater than 300 F.Caused by Personnel Error.Permanent Maint Procedure to Disable/Enable SIS Actuation on Low Pressurizer Pressure Will Be Revised to Align W/Ts ML18065A5021996-02-15015 February 1996 LER 96-003-00:on 960115,technicians Found Low Voltage cut- Off for Alternate Shutdown Panel Inverter Set That Resulted in Unavailability of Panel.Caused by Inadequate Post Mod. Readjusted Set Point to Minimum setting.W/960215 Ltr ML18065A4581996-01-31031 January 1996 LER 96-001-00:on 960103,failed to Test Duplicate Equipment. Caused by STS No Longer Containing Requirement for cross- Train Testing of Duplicate Components.Will Submit Request to Delete Subj Requirements from TS.W/960131 Ltr ML18065A4421996-01-19019 January 1996 LER 95-016-00:on 951226,did Not Analyze Primary Coolant Samples within 72 H.Caused by Belief Acceptability to Save Pcs Samples for Choride Analysis Past 72 H.Counseled Chemistry Supervision.W/960119 Ltr ML18065A4041996-01-15015 January 1996 LER 95-014-00:on 950119,PCP Oil Collection Deficiencies Created by FC-860 Piping Mod.Caused by Inadequate DBD for Sys & Lack of Review by Experienced Fire Protection Personnel.Updated Design Basis documentation.W/960115 Ltr ML18065A3291995-12-0404 December 1995 LER 95-013-00:on 951103,circuit Fuse Coordination Deficiency Which Affects App R Safe Shutdown Equipment Noted.Design of Fuse Coordination in Potential Transformer Circuits Will Be Evaluated & Modified as required.W/951204 Ltr ML18065A2361995-11-0202 November 1995 LER 95-012-00:on 950701,discovered Unqualified Electrical Connection in Containment SW Outlet Valve Controller.Caused by Failure of Assigned Engineers to Available Info.Replaced Wire Nuts W/Inline Butt connections.W/951102 Ltr ML18065A2051995-10-20020 October 1995 LER 95-008-01:on 950728,discovered That None of Four Containment High Pressure Channels Would Initiate Reactor Trip Due to Programmatic Deficiencies.Administrative Procedure (AP) 9.44,AP 9.45 & AP 10.44 Will Be Revised ML18065A0841995-09-18018 September 1995 LER 95-011-00:on 950817,CR 40 Withdrawal Occurred When Given Insertion Signal Due to skill-based Error in Crimping & Removing Foreign Matl from CRDM Motor Connection Box.Crd Package replaced.W/950918 Ltr ML18065A0681995-09-14014 September 1995 LER 95-010-00:on 950815,ESFA Resulted in Manual Rt Following Isolation of Pcs.Replaced Failed Instrument Line ML18065A0651995-09-0808 September 1995 LER 95-009-00:on 950728,discovered Lack of Procedural Guidance for Pump Repair Following Fire.Proposed Use of Power Supply Breaker Did Not Adequately Address Effect of Loss of Control Power.Performed Independent Assessment ML18064A8781995-08-28028 August 1995 LER 95-008-00:on 950728,discovered During Design Change Testing That None of Four Containment High Pressure Channels Would Initiate Rt.Caused by Programmatic Deficiencies. Reviewed Selected Tests & Mods from Recent Refueling Outage ML18064A8831995-08-21021 August 1995 LER 95-007-00:on 950720,discovered That 12 Instrument Loops Had V-bolted Type Qualified Cable Splices Connected to Wires W/Exposed Kapton Insulation.Caused by Human Error.All V- Bolted Splices Replaced w/in-line design.W/950821 Ltr 1999-09-02
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML18066A6901999-11-0101 November 1999 Rev 5 to Palisades Nuclear Plant Colr. ML18066A6761999-09-30030 September 1999 Monthly Operating Rept for Sept 1999 for Palisades Nuclear Plant ML18066A6271999-09-0202 September 1999 LER 98-011-01:on 981217,inadequate Lube Oil Collection Sys for Primary Coolant Pumps Was Noted.Caused by Design Change Not Containing Appropriate Level of Rigor.Exemption from 10CFR50,App R Was Requested.With 990902 Ltr ML18066A6351999-08-31031 August 1999 Monthly Operating Rept for Aug 1999 for Palisades Nuclear Plant ML18066A6771999-08-31031 August 1999 Operating Data Rept Page of MOR for Aug 1999 for Palisades Nuclear Plant ML18066A6221999-08-20020 August 1999 LER 99-002-00:on 990722,TS Surveillance Was Not Completed within Specified Frequency.Caused by Failure to Incorporate Revised Frequency Into Surveillance Schedule in Timely Manner.Verified Implementation.With 990820 Ltr ML18066A6061999-07-31031 July 1999 Monthly Operating Rept for July 1999 for Palisades Nuclear Plant.With 990803 Ltr ML18066A5201999-06-30030 June 1999 Monthly Operating Rept for June 1999 for Palisades Nuclear Plant.With 990702 Ltr ML18066A4841999-05-31031 May 1999 Monthly Operating Rept for May 1999 for Palisades Nuclear Plant.With 990603 Ltr ML18066A6371999-04-30030 April 1999 Revised Monthly Operating Rept for Apr 1999 for Palisades Nuclear Plant ML18068A5941999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for Palisades Nuclear Plant.With 990503 Ltr ML18066A4161999-04-0101 April 1999 Rev 4 to COLR, for Palisades Nuclear Plant ML18066A4501999-03-31031 March 1999 Monthly Operating Rept for Mar 1999 for Palisades Nuclear Plant.With 990402 Ltr ML18066A4671999-03-31031 March 1999 Rev 0 to SIR-99-032, Flaw Tolerance & Leakage Evaluation Spent Fuel Pool Heat Exchanger E-53B Nozzle Palisades Nuclear Plant. ML18068A5351999-02-28028 February 1999 Monthly Operating Rept for Feb 1999 for Palisades Nuclear Plant.With 990302 Ltr ML18066A3931999-01-31031 January 1999 Monthly Operating Rept for Jan 1999 for Palisades Nuclear Plant.With 990202 Ltr ML18066A3781999-01-20020 January 1999 LER 98-013-00:on 981222,safeguards Transfer Tap Changer Failure Caused Inadvertant DG Start.Caused by Failed Motor Contactor.Contactor Was Replaced.With 990120 Ltr ML20206F6131998-12-31031 December 1998 1998 Consumers Energy Co Annual Rept. with ML18066A3651998-12-31031 December 1998 Monthly Operating Rept for Dec 1998 for Palisades Nuclear Plant.With 990105 Ltr ML18066A3421998-11-30030 November 1998 Monthly Operating Rept for Nov 1998 for Palisades Nuclear Plant.With 981202 Ltr ML18066A3301998-11-11011 November 1998 Part 21 Rept Re Potential Safety Hazard Associated with Wrist Pin Assemblies for FM-Alco 251 Engines at Palisades Nuclear Power Plant.Caused by Insufficient Friction Fit Between Pin & Sleeve.Supplier of Pin Will No Longer Be Used ML18068A4921998-10-31031 October 1998 Monthly Operating Rept for Oct 1998 for Palisades Nuclear Plant.With 981103 Ltr ML18068A4851998-10-29029 October 1998 LER 97-011-01:on 971012,starting of Primary Coolant Pump with SG Temps Greater than Cold Leg Temps Occurred.Caused by Inadequate Procedures & Operator Decision.Sop Used for Starting Primary Coolant Pump Enhanced ML18066A3181998-09-30030 September 1998 Monthly Operating Rept for Sept 1998 for Palisades Nuclear Plant ML18066A2901998-08-31031 August 1998 Monthly Operating Rept for Aug 1998 for Palisades Nuclear Power Plant.With 980903 Ltr ML18066A3191998-08-31031 August 1998 Revised Monthly Operating Rept Data for Aug 1998 for Palisades Nuclear Plant ML18066A2831998-08-18018 August 1998 LER 98-010-00:on 980721,reactor Manually Tripped.Caused by Failure of Coupling Which Drives Feedwater Pump Main Lube Oil Pump.Main Lube Oil Pump Coupling & Associated Components Replaced & Satisfactorily Tested ML18066A2771998-08-13013 August 1998 Part 21 Rept Re Deficiency in CE Current Screening Methodology for Determining Limiting Fuel Assembly for Detailed PWR thermal-hydraulic Sa.Evaluations Were Performed for Affected Plants to Determine Effect of Deficiency ML20237E0301998-07-31031 July 1998 ISI Rept 3-3 ML18066A2701998-07-31031 July 1998 Monthly Operating Rept for July 1998 for Palisades Nuclear Plant.W/980803 Ltr ML18066A2311998-06-30030 June 1998 Monthly Operating Rept for June 1998 for Palisades Nuclear Plant ML18066A2261998-06-30030 June 1998 LER 98-009-00:on 980531,small Pinhole Leak Found on One of Welds,During Leak Test Following Replacement of Pcs Sample Isolation Valves.Caused by Welder Error.Leaking Welds Repaired ML18066A3061998-06-18018 June 1998 SG Tube Inservice Insp. ML20249C4951998-06-17017 June 1998 Rev 1 to EA-GEJ-98-01, Palisades Cycle 14 Disposition of Events Review ML18066A1781998-06-0909 June 1998 LER 98-008-00:on 980511,noted That Procedure Did Not Fully Satisfy Requirement to Test High Startup Rate Trip Function. Caused by Misunderstanding of Testing Requirements.Revised TS Surveillance Test Procedure & Reviewed Other Procedures ML18066A1711998-06-0101 June 1998 Part 21 Rept Re Impact of RELAP4 Excessive Variability on Palisades Large Break LOCA ECCS Results.Change in PCT Between Cycle 13 & Cycle 14 Does Not Constitute Significant Change Per 10CFR50.46 ML18066A1741998-05-31031 May 1998 Monthly Operating Rept for May 1998 for Palisades Nuclear Plant.W/980601 Ltr ML18066A2321998-05-31031 May 1998 Revised MOR for May 1998 for Palisades Nuclear Plant ML18068A4701998-05-31031 May 1998 Annual Rept of Changes in ECCS Models Per 10CFR50.46. ML18065B2451998-05-13013 May 1998 LER 98-007-00:on 980413,HPIS Sys Was Noted Inoperable During TS Surveillance Test.Caused by Performance of Flawed Procedure.Operators & Engineers Will Be Trained to Improve Operational Decision Making Through Resources & Knowledge ML18066A2331998-04-30030 April 1998 Revised MOR for Apr 1998 for Palisades Nuclear Plant ML18068A3461998-04-30030 April 1998 Monthly Operating Rept for Apr 1998 for Palisades Nuclear Plant.W/980501 Ltr ML18066A3411998-04-22022 April 1998 Rev 0 to EMF-98-013, Palisades Cycle 14:Disposition & Analysis of SRP Chapter 15 Events. ML18065B2071998-03-31031 March 1998 Monthly Operating Rept for Mar 1998 for Palisades Nuclear Plant.W/980403 Ltr ML20217C2741998-03-31031 March 1998 Independent Review - Is Consumers Energy Method (W Method) of Determining Palisades Nuclear Plant Best Estimate Fluence by Combining Transport Calculation & Dosimetry Measurements Technically Sound & Does It Meet Intent of Pts ML18066A2341998-03-31031 March 1998 Revised MOR for Mar 1998 for Palisades Nuclear Plant ML18068A3041998-02-28028 February 1998 Monthly Operating Rept for Feb 1998 for Palisades Nuclear Plant.W/980302 Ltr ML18066A2351998-02-28028 February 1998 Revised MOR for Feb 1998 for Palisades Nuclear Plant ML18065B1641998-02-0505 February 1998 Rev 0 to Regression Analysis for Containment Prestressing Sys at 25th Year Surveillance. ML18067A8211998-01-31031 January 1998 Monthly Operating Rept for Jan 1998 for Palisades Nuclear Plant.W/980203 Ltr 1999-09-30
[Table view] |
Text
NRC Form 366 U.S. N.UCLEAR REGULATORY COMMISSION~,
19*831 APPROVED OMB NO. 3160-0104 EXPIRES: 8/31 /86 '
LICENSEE EVENT REPORT ILER)
FACILITY NAME 111 DOCKET NUMBER 121 PAGE 131 Palisades Plant I I I I I I I
.0 5 0 0 0 2 5 5 1 I OF I 0 8:
TITLE 141 FUEL ROD FAILURE AND SUBSEQUENT LOSS OF SPECIAL NUCLEAR MAT.ERIAL DISCOVERED FOLLOWING REFUELING OPERATIONS - SUPPLEMENTAL REPORT ,
EVENT DATE 161 LER NUMBER 161 REPORT DATE 161 OTHER FACILITIES INVOLVED 181 SEQUENTIAL
- REVISION FACILITY NAMES MONTH DAY YEAR YEAR NUMBER NUMBER MONTH DAY YEAR N/A 939j3 old4 011 N/A THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR l: (Ch<<k,,,,. or"""9of1M following/ 1111 OPERATING POWER MOOE 191 I
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CAUSE SYSTEM COMPONENT TUR ER TO NPROS CAUSE SYSTEM COMPONENT TUR ER TO NPROS 1* .I I I I I I I I I I I I I . ':*::~
I '
I I I I I I I I I I I I I SUPPLEMENTAL REPORT EXPECTED 1141 MONTH DAY YEAR
'l EXPECTED YES Vf y ... com~oto EXPECTED SUBMISSION DATE!. ;i NO SUBMISSION DATE 1161 I I I ABSTRACT IUmit to 1400.,,.coa, i.e.. epprr>1ti,,..toly fifteen aing~.,,.c* typewritten lin ..I 116)
On june 30, 1993, at approximately.2300. hours, while draining the refueling cavity in preparation far* re~attaching the reactor head to the reactor vessel, an object located in the reactor cavity tilt pit exhibited contact dose rates of approximately 7000R/hr.
A review of a remote camera inspection video tape led to the postulation that the object was a piece of fuel rod.* Further remote camera inspection of the tilt pit resulted in the discovery of three additional pieces of what appeared to be a fuel rod. Subsequent investigation determined that fragmented pi.eces of failed fuel rod S-15 dislodged from fuel assemb.ly 1-024 during refueling operations.
- The failure of the fuel rod was caused by a' core shroud and fuel assembly interface problem that resulted in the wear and failure of a single fuel rod. The damaged fuel rod became dislodged from the _fuel a~sembly during refueli~g operations.
Corrective action for this event includes increased. f~el assembly inspections, inspection of the core shroud during the next full core offload, Cycle 11 core redesign incorporating stainless st~el rods in selected fuel assemblies, limiting the use of the standard bi-metallic fuel assembly design to four cycles or less; continued periodic reactor noise analysis, procedure changes, and implementation of the Failed Fuel Response Plan.
9310190062 931014 ;
PDR ADOCK 05000255 S PDR I L.
NRC Form JeeA U.S. NUCLEAA REGULATORY COMMISSIO" 19*831 APPA0\/£0 OMB NO. 3160-0104 EXPIRES:. 8131186
.LICENSEE EVENT REPORT llERI TEXT CONTINUATION FACILITY NAME 111 . OOCKE'T NUMBER 121 LER NUMBER Ill S£QUEHT1.Al '11£\/ISION YEAA NUMBER NUMBER Palisades Plant o 6 *5 0 0 *O 2 .5 5 9 3 - 0 0 4 - O. 1 0 2 0~ 8 :
EVENT DESCRIPTION On June 30, 1993~ at appr~ximately 2~00 h~urs, ~hil~ draining the refueling cavity in preparation for re-attaching the reactor head .to the reactor vessel, radiological dose rates in the reactor cavity near the t n t pit [OF] exceeded the dose rates typically experienced during previous similar refueling cavity draining evolutions. At the time of the event the reactor head was in place over the reactor vessel resting on shims.
Typical dose rates at the floor level of the refueling cavity ne.ar the tilt pit (elev.
625-feet) are 200-300 mR/hr; however, during this event the dose rate on the refueling machine bridge (elev. 649;feet) was 700 mR/hr with no water in the tilt pit. A~ object located on the tilt pit floor (elev. 610-feet).; exhibited contact dose rates of approximately 7000R/hr.
- The refueling cav-ity was immediately evacuated and the radiol6gical conditions assessed. Approximately two feet of water was added to the tilt pit to provide shielding. Prop~~ radiol-0gical postings and boundaries were established, and access to the containfuent area was controlled. At the time of the event the reactor was in a refueling mode. There was no radiological release to the environment as* a .result of this event, and there were no personnel exposures that exceeded either 10 C~R Part 20 limits .or CPCo administr*tive limits .. This event had no adverse effect on the health and safe.ty of the *public.
A remote ~amera inspection of the tilt pit ~ai.conduct~d and a cylindrical Object approximately five (5) feet in length and approximately fou~-tenths (0.4) i~ch in diameter was identified. It was suspected that the -Object was a piece *of a*fuel rod
[AC]. On July 1, 1993 the NRC was notified of the possibility of a fuel rod in the reactor cavity.tilt pit.
- Further remote camera inspection of the tili pit resulted tn the identification of three more pieces of what appeared to be a fuel rod. The* total length of all four pieces was* estimated to be about 12 feet. A review of the video tape.*from the remote camera inspection of the thre~ additibnal objects revealed that one of the pieces had an end cap and the serial number was visible. Based on the serial number, it was determined that*the fuel rod came from'fu~l assembly 1-024 which was in the reactor core. The 1-024 fuel assembly had been removed from the reactor during refueling, taken to the tilt pit, rotated_l80 degrees and returned to its core position~
In response to these de~~lopments, CPCo formed .a project.team to develop an action plan for recovery of the fuel rod pieces from the tilt pit, recovery of the damaged fuel assembly from the reactor core, and analysis of the entire event. *
- On July .4, 1993 the:three fUel rod fragments*were retrieved and relocated to storage baskets in the tilt pit. It was determined th~ fourth piece was not a fuel rod fragment and tt was not recovered.* By July 6, 1993 a plan.had be~n *developed and.
approved by the Plant General.Manager and the NRC for the recovery of fuel assembly I-024 from the reactor <ore. The reactor head was removed and placed on the reactor head stand. Preparatio~s were then made to remove the Upper Guide Structure (UGS) from the reactor v.essel. During the lift ._of the. UGS, the load cell readout indicated a load *I.:
greater than anticipated. A remote camera i~spection of the underside of the UGS
- confirmed that a fuel assembly still in its core position was being lifted with, the UGS. The UGS lift was halted and the containment was evacuated. An Unusual Event was
NRC F0tm 3HA .
U.S. NUCLEAA REOUL..*.-l'ORY COMMISSION 19*831
. APPflOVEO OM.B 0jO. 3160-010*
' EXPIRES: 11311116 LICENSEE EVENT REPORT (LERI TEXT CONTINUATION FACILITY NAME f1 I. OOCll;ET NUMBER 121 LER NUMBER 131
- PAOE l'I SEQUENTIAL REVISION YEAA NUMBER NUMBER Palisades Plant Q 5 Q Q Q 2 5 5 9 3 - Q Q . 4 - Q 1 Q 3 OF Q 8 declared at 2254 hours0.0261 days <br />0.626 hours <br />0.00373 weeks <br />8.57647e-4 months <br /> on July 6, 1993 .. Ther~ was no radiological release to the environment as a result of the lifting of a fuel assembly with the UGS, and there were no exposures that exceeded either 10 CFR Part 20 limits or .CPCo administrative li~its.
The lifting of a fuel as~embly with.the UGS had no adverse effect ori the health and safety of the public.
A.closer examination of the location of the fuel assembly attached to the UGS indicated that the fuel assembly was attached to. the UGS in a location where fuel assemblies had been stuck to the UGS on two previous occasions. (See.LERs 88015, dated October 3, 1988 and 92017, dated March 30, 1992.} All reactor vessel work was stopped pending recovery of the fuel assembly stuck to the UGS. Containment integrity was established by closing the equipment hatch and routine work activities in the containment were suspended. Procedures_ w~re then developed for the recovery of the stuck fuel assembly.
On July 8, 1993 the fliel *assembly, .while still in its ~ore position, was successfully removed from the UGS and placed on the reactor vessel core support plate. The UGS was then lifted without further incident and was placed in its storage location in the
. reactor cavity. The fuel assembly that was lifted with the UGS was then moved to the spent fuel pool for examination. Also on July 8,_1993, an NRC Augmented Inspection*
I.
Team (All) arrived at Palisades to investigate the broken fuel rod.found in the reactor cavity tilt pit, the lifting of a fuel assembly ~uring removal of the UGS, and other recent issues. **
On July ll, 1993 fuel assembly 1-024 was removed from the reactor core. Prior to removal from the reactor core, fuel assembly 1-024 had been visually inspected to ensure that additional fuel rods would not be damaged during removal from the reactor core. The visual inspection of fuel assembly 1-24 while it was in th~ reactor core was.
accomplished by removing an adjacent fuel assembly and an adjacent control rod. Prior to removal, it w~s noted th~t.the upper end piece of the failed fuel rod was still contained within the uppermost spacer grid of the 1-0~4 fuel ~ssembly. During the removal of the 1-24 fuel assembly from the reactor core, this piece of fuel rod dropped from the fuel assembly and landed on top of another fuel assembly tieplate in the core.
The piece that had fallen from fuel assembly 1-024 was retrieved from the core and was stored with the other three fuel rod pieces. The 1-024 fuel assembly was subsequently relocated to the spent fuel pool, along with the pieces of damag~d fuel rod, where inspections by CPCo personne 1 and the fue 1 vendor could be conducted. .*
Inspection of the 1-024. fuel assembly and the broken fuel rod have bee*n completed.
Inspection of.the reactor core and lower vessel area for loose fuel pellets, other debris, and'other indications of fuel damage bas been completed. The results of these inspections were used t~ determine a root cause for the failur~ of fuel assembly 1-024 I.
and to develop corrective actions associated with this event. *
- This event is reportable to the NRC in accordance with 10CFR50.73(a}(2)(ii} as an event wherein a principal safety barrier (i.e., fuel cladding) was seriously degraded.
'*I NRC f0tm 3&8A U.S. HUCLEAA REOUL.ATORY COMMISSlO" lf.831 Al'PflOVEO OMB NO. 3160~104 :
. EXPIRES: 1131.116 LICENSEE EVENT REPORT ILER) TEXT CONTINUATION FACILITY H.AME 111 OOCKET HUMBER 121 LEA NUMBER 131 PAOE 141 SEQUENTIAL REV1SION YEM HUMBER
- NUMBER Palisades Plant olslololol2lsls 913 - oIo 14 - 0 11 014. OF o1s I i
CAUSE OF THE EVENT The failure of the fuel rod from fuel assembly 1-024 .was caused by a core shroud and
. fuel assembly interface problem that resulted in the wear and fail~re of a single fuel rod.
This event involved the failure of a principal safety barrier (fuel cladding) and is considered a failure of equipment important to safety.
ANALYSIS OF THE EVENT Fragmented pieces of failed fuel rod S-15 from fuel assembly 1-024 were found in the reactor side tilt pit following th~ initial draining of the re~ctor cavity near the end of Cycle IP refueling outage. Based on inspections of the failed fuel assembly, fragmented fuel rod pieces, and the core shroud corner location where fuel assembly 1-024 was located, the following conclusions have been made:
- 1. The fuel rod was failed and severely damaged during Cycle 10 operation;
- 2. The upper *portion of the fuel rod and the associated corners of spacers 6 through 9 were rubbing against the core shroud during Cycle 10 operation.
- 3. A circumferential break in Span 9 e~isted on the failed rod during Cycle 10 operation. This is *believed to be due to secondary hydriding. The initial primary failure is believed to have originated in Span 5 or 6 due to rod fretting against the core shroud.
- 4. The rod was peeled from the fuel assembly while being handled over the reacto~
side tilt pit during the initial ~nd of Cycle 10 core fuel shuffle.*
- 5. As the rod was peeled from the fuel assembly, it was broken into several pieces.
This peeling is believed to be the caus~ of damage to the corners of spacers 1 through 5 .
.6. A total of six fragmented rod ~ieces were found. The entire length of the failed rod has been accounted. for; however, approximately three feet of partial circumferential cladding (1/3 to 1/2 circumference) remains missing. *
- 7. The missing partial cladding is believed to have worn or broken away during Cycle 10 operation. One to three cladding shards may exist that are equivalent in size to one of the shards found (which was one~foot long, about 90 degrees circumference, and worn down by the core shroud). *
- 8. Approximately five feet of fuel, 213 pellets, is missing from the retrieved fragmented rod pieces~
.__ _______________________________________ -..):
. 'r I
NRC Form 388A 111*131 . "*" """. . ""~"" """"" 'l AP9110VEO OMB N*O. j 1&0-01 O*
EJl:PIRES: 8131 /H LICENSEE EVENT .REPORT (LERI TEXT CONTINUATION FACl~ITY NAME 111 OOCKET NUMBER 121 . LEll NUMBER 131 . PAGE l'l SEQUENTIAL REVISION*
NUMBER NUMBER Palisades Plant 0 5 0 0 Q 2 5 5 9 3 - 0 Q 4 - Q 1 Q .5 OF Q 8 Root Causes That Are Considered Likely*
- A core shroud and fuel assembly interface probl~m is considered the likely proximate cause. The root cause(s) must still.be determined coriside~ing potential contributing.
factors~
Root causes being considered~
- 1. Shroud distortion due to operating conditions.
- 2. Shroud distortion due to loose or broken bolting.
- 3. Misalignment between the UGS and the core support barrel.
- 4. The problem may have always *existed from :the original as-built conditions; however, the add~tion of some ~ontributing factors caused the I-024 failed rod
.event. * *
- Contributing factors being considered:
- 1. Fuel assembly I-024 was in the car~ five ~ycle~.
- 2. Minor damage *on fuel assembly 1-024 may have existed from a handling event.
- 3. Fue.l assembly I-024 had loose spacer grids.
- 4. Increased PCS flow due to the steam generator replacement after Cycle 9.
- 5. Crire bar~el vibration changes.
- 6. Localized PCS flow changes* due to introduction of (HTP) High Thermal Performance fuel assemblies.
- 7. Fuel assembly* bow. *
- 8. -~uel assembly twist.
Six of the above contributing factors 1, 3, 4, 5, 6, and 7 are considered key factors to be specifically addressed for operation of CycJe:11 and future cycles. Contributing factor 2 was addressed to some extent during the root cause analysis. Refueling equipment was *inspected for damage or snag hazards to verify no generi.c handling damage issue existed. Contributing factor 8 may have some subtle contribution with respect to how a fuel assembly interfaces with its surroundings; however, fuel assembly twist was a minor contributor to the failed rod event since the fuel assembly's upper and lower tie pl~tes are held in position by the Upper Guide Structure lower alignment plate and the lower core support plate, respectively. *Any fuel assembly* twist would tend to be reduced or eliminated due to the tight positioning tolerance provided by the alignment ins and ali nment holes. *
\" '
\ J NRC Fotm 3HA 19*8ll
.* "' """"' "'~'"' """""'"\.1i\*
.. *APPROVED OMS )jo. l160~10*
EXPIRES: 8131186 LICENSEE EVENT REPORi: (LERI TEXT CONTINUATION FACILITY NAME.11) oocic:t; NUMBER 121 LER NUMBER 131 PAGE 1'1 SEQUENTIAL REVISION YEAR NUMBER NUMBER
,1 Palisades Plant 0 5 0 0 0 2,. 5 5 9 *3 - 0 *4 - 1 8 l 0 0 0 6 OF 0 Disposition of Missing Material
- Material "missing from fuel assembly 1-024 and failed fuel rod. S-15 is suinmarized as: . 'I Mi ss.ing Cladding SJ .gr~ms Missing Pellets 938 grams Missing Insulator Disk 2 grams Missing Spacer Pieces (not quant Hi ~d, see below)
A total ~f six fra~mented rod.pieces were found and ~etrieved. The entire length of the failed fuel rod has been accounted for; however; :approximately three feet of*
partial circumferential cladding (1/3 to 1/2 cir,cumference) is missing. The missiryg partial cladding is believed to have worn away during Cycle 10 operation at least to some extent. We believe that o~e to three cladding shards may exist that aie
- equivalent in size to one of the shards. retrieved (which was one-foot lon*g, about 90 degrees in circumference, and apparently .worn away by interaction with the core shroud). The missing cladding shards may have broken intb smaller ~ieces.
Approximat~ly five feet of fuel pellet material is missing from the retrieved fragmented fuel. rod pieces. Remedial corre~tive action with.respect to accountability and ~mpact of. the missing fuel is ~iscussed in our September 30, 199~ letter.
- In addition to the missing fuel rod material~ spacer material is'mtssing fro~ the damaged corner of fuel ~ssembly I-024. Most of the-missing material consists of small portions of the side plates in the area of the failed.fuel rod. A very small amount of internal strip material and one lantern spring from, spacer 9 are als.o *missing.
A search for !Jlissing material was performed in the core location where fuel assembly I-024 resided. The bottom of the reactor vessel under the core support plate, the top
.of the core, the r~act6r cavity iilt pit, the transfer tube, and the spent fuel pool side south tilt pit were also inspett~d.
- The.missin~ partial claddin~ was:not located.
Three small pieces of spacer side p~ate fu~terial were located on the core shroud and on the core plate, and were retrieved using the ~ormal ~acuuming equipment. It is
- possible that' .other missing spacer pieces and small cladding pieces were retrieved during the several. tilt pit, reactor cavity fl*oor, or core region vacuumings that.took pl a.ce during the refueling outage.
Some spacer .and cladding materi~l has nof'.*been found; If this material. still resides
- within the primary coolant system, the 'potential exists for fuel rod fretting after the primary coolant pumps are returned to service. The impact of fuel **rod fretting will be
- mitigated since 136 of the 204 total fu~l assemblies incorporate a debris resistant design.
Additionally, it is recognized that d~bris i~ the PCS *ha~ the potential td affect PCS*
r internal components such as valve i nt'erna 1s. and steam. generator tubes.* The majority ~f j
NRC Form 388A U.S. NUCLEAR REGULATORY COMMISSION 11*831 APPROVED OMB NO. 3160-010' EXPIRES: 8/31 /86 LICENSEE EVENT REPORT (LERI TEXT CONTINUATION FACILITY NAME 111 ' DOCKET NUMBER 121 LER NUMBER 13) PAGE 1'1 SEQUENTIAL.
- REVISION YEAR. NUMBER NUMBER*
- Palisades Plant Q* 5 Q Q Q 2 5 5 9 3 - Q Q 4 - Q *1 Q 7 OF Q 8 .
the 5~ gram~ (0.12 pounds, plus.a slight additio~ due to spacer material) of missing non-fuel material is zircaloy. The missing material will cause little fretting wear against stainless steel or Inconel components. The effect of the missing 53 g~ams of material on other components, such as valve internals, is considered to be minimal based on previous experience at Palisade~.
CORRECTIVE ACTION Corrective action for this event includes:*
I. Inspection of a minimum of four fuel* assemblies in the shroud corner locations every refueling outage.
- 2. Performing a detailed inspection of th.e core* shroud after the next core offload.
- 3. Attempting to retrieve the as-built drawings and documentation of clearances between the core shroud and the fuel assembl*ies.
- 4. Limitiri~ the use of the standard b\-metallic fuel assembly design to four cycles
- 5. Continued inspection of the High Thermal Performance spacer grid assemblies to confirm they meet their de~ign.
- 6. For Cycle 12, implement the planned shield fuel assembly design*, or configure
. *-burned fuel assemblies placed in the shroud corner positions such that the fuel assembly bow .is oriented toward the core and away from the shroud.
- 7: Continued pe.riodic reactor noise *analysis utilizing the ex-cor'e neutron detectors.
In additio~, 16 "L" fuel assemblies ~ill b~.used in the Cycle 11 .co~e design and will be located in the baffle corner locatiQns. The 16 "L" fuel assemblies have 14 fuel rods replaced by .oversized stainless stee1 rod_s . . Eight of the stainless steel rods are oriented in the corner of th~ *fuel assembly which interfaces with th& shroud corner to mitigate the consequences of a potential fuel assembly failure similar to that -
experienced by the 1-024 fuel assembly. The* other three corners of each assembly have two stainless steel rods each.
Miscellaneous further correcti~e actions iricl~de:
- 1. Incorporating the lessons learned from this event into the fuel performance monitoring procedures~
- 2. Evaluating the need to perform supplemental noise monitoring during Cycle 11 utilizing externally mounted vibration monitoring equipment.
- 3. Implementation of the Failed Fuel Response Pla~ to monitor future fuel failure.
) NRC Form 399A U.S. NUCLEAA REGUl.ATORY COMMissio ..
19*831 APl'llOllED OMB NO. 31&0-<l104
[)(PIRES: 813118&
LIC.ENSEE EVENT REPORT I (LERI TEXT CONTINUATION FACILITY NAME Ill DOC II.ET NUMBER 121 LER NUMBER 131 SEOUEHTIAl REVISION YEM NUMBER NUMBER Palisaqes Plant 0 5 0 0 0 2 5 5 9 .3 - 0 0 4* - 0 1 Q 8 OF Q 8 ADDITIONAL INFORMATION
- A. detailed description and the results of the* root cause analysis for this event are contained-in a letter from Consumers Power Company to the NRC dated' September 30, 1993 .
.'