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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
- Power GB Slade General Manager POWERiNii MICHlliAN'S PROliRESS Palisades Nuclear Plant: 27780 Blue Star Memorial Highway. Coven. Ml 49043 October 18; 1993 Nuclear Regulatory Commission*
Document Control Desk Washington, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT - LICENSEE EVENT REPORT 93-010 - EXCEEDING THE PRIMARY COOLANT SYSTEM COOLDOWN RATE AS DEFINED IN THE TECHNICAL SPECIFICATIONS .
Licensee Event Report (LER)93-010 is attached. This event is reportable in accordance with 10CFR50.73(a)(2)(i)(B) as. operation of the plant outside the plant's Technical Specifications .
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fe;~ 1d B si ade _j General Manager CC Administrator, Region Ill, USNRC NRC Resident Inspector - Palisades Attachment n-or.n c... J\ , '* ..
9310250185 931018 PDR
- ADOCK 05000255 S PDR t *.*
- A CM5NE7?GYCOMPAN'r'.
- CELL 1l t
NRC Form 366 19*831
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- LICENSEE EVENT REPORT (LERI
- U.S. NUCLEAR REGULATORY COMMISSION APPROVED OMB NO. 3160-0104 EXPIRES: 8/31 /86 FACILITY NAME 111 DOCKET NUMBER 121 PAGE 131 I
I Palisades Plant 015101010121515 1 OF 018 TITLE 141 EXCEEDING THE PRIMARY COOLANT SYSTEM COOL DOWN RATE AS DEFINED IN THE
.~ TECHNICAL SPECIFICATIONS EVENT D.ATE 161 LER NUMBER 161 REPORT DATE 161 OTHER FACILITIES INVOLVED !Bl SEQUENTIAL REVISION FACILITY NAMES MONTH DAY *YEAR YEAR NUMBER NUMBER MONTH DAY YEAR
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' N/A 0 1~1°1°1°1 I
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0 19 ih 9 3 913 ( ol 1 lo o lo i I o 1 I fl q I ~ N/A 0161010101 I THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR t: IChKk OM°' more of tM following/ 1111 N
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below and in Text, 20.4061oll1 llivl 60.73toll2lliil 60. 7 3toll211viiillBI NRC Form 366AI 20.4061oll1 llvl 60. 7 31oll211iiil 60.731oll211xl LICENSEE CONTACT FOR THIS LER 1121 NAME TELEPHONE NUMBER Cris T. Hillman, Staff Licensing Engineer 6ARtA1CI°~ I 716141 -18191113 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT 1131 '
MANUFAC* REPORTABLE MANUFAC* REPORTABLE CAUSE SYSTEM COMPONENT TUR ER TO NPROS CAUSE SYSTEM COMPONENT TUR ER TO NPROS 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 I n
SUPPLEMENTAL REPORT EXPECTED 1141 MONTH DAY YEAR '
EXPECTED SUBMISSION YES Vf y ... comp/ere EXPECTED SUBMISSION DATE!
~NO DATE 1161 ABSTRACT fl..imit to 1400 spaco:i. i.e., approxirnaioty fihoen 6in(ll.-st>>e* typt1written line:i) 1161 I I I On September 17, .1993' at 1356 hours0.0157 days <br />0.377 hours <br />0.00224 weeks <br />5.15958e-4 months <br />, with the plant in cold shutdown, a primary coolant system (PCS) cooldown was in progress to perform repairs on a leaking pressurizer relief valve nozzle. During the cooldown, the PCS cooldown rate of 20°F/hr in any one hour, as defined in the Technical Specifications, was exceeded.
The cause of this event was a combination of personnel error and inadequate procedures.
Corrective action for this event includes evaluations of the affect on reactor vessel material as a* result of this event, evaluations of the heat-up and cooldown processes used at Palisades, procedure evaluations, veri fi ca ti on of proper temperature monitoring techniques for heat-up and cooldown, verifying equipment operation and reliability, remedial training and simulator performance evaluations of the operating crew involved in this event, management discussions with the operating crews about the implications of this event, and incorporating the. lessons learned from this event into training lesson plans.
\J.S. N\JCLEAA R£GUL.llTORY COM ... tSSIO"19-831 AP9ROVED OMB NO. 3160-0*0*
EXPIRES: 8131.116 LICENSEE EVENT REPORT (LERI TEXT CONTINUATION FACILITY NAME 11 I OOCl'lET NUMBER 121 LER NUMBEJI 131 PAGE ' "
SEQUENTIAi. REVISION YEM NUMBER NUMBER Palisades Plant Q 5 0 0 Q 2 .5 5 9 3 - Q 1 Q - 0 Q Q 2 OF Q 8 EVENT DESCRIPTION On September 17, 1993, at 1356 hours0.0157 days <br />0.377 hours <br />0.00224 weeks <br />5.15958e-4 months <br />, with the plant in cold shutdown, a primary coolant system (PCS) cooldown was in p~ogress. During the cooldown, the PCS cooldown rate of 20°F in any one hour with the cold leg temperature less than 170°F, as defined in Technical Specification 3.l.2a, was exceeded. At the time of the event, the shutdown cooling system [BP] was in service to reduce PCS temperature. The primary coolant pumps had been removed from servi.ce to permit depressurization of the primary ~oolant system following the identification of, and subsequent increased leakage from a through-wall crack on the pressurizer [AB;PZR] power operated relief valve [AB;RV] nozzle. During this period, the leakrate from the PORV nozzle was initially estimated to be 0.1 gallons per minute (gpm), based on the level increase in the containment sump. The PCS cooldown rate was subsequently calculated to be 49°F in the hour following the removal of the primary coolant pumps from service based on the most limiting temperature indicators.
This event is reportable to the NRC in accordance with 10CFR50.73(a)(2)(i)(B) as operation of the plant outside the plant's technical specifications.
CAUSE OF THE EVENT The cause of this event was a combination of personnel error and inadequate procedures.
Because this event involved personnel error, the following informatio~ is provided in accordance with 10CFR50.73(b)(2){J):
(J)(l) Operator action which affected the course of this event was the removal from service of the primary coolant pumps. The removal from service of the primary coolant pumps was a planned evolution during the normal cooldown process of the reactor and was controlled by procedure. System Operating Procedure (SOP) 1, "Primary Coolant System," contributed to the event in that it provided only general guidance as to the frequency of recording PCS heat-up or cooldown information, specifically, " ... data shall be recorded hourly or more frequently ... " Furthermore, the procedure did not sufficientlj caution the operator on what to expect once the PCPs were removed from service.
(J)(2)(i) The error was cognitive in that the reactor operators monitoring the cooldown were aware of the limits for the cooldown rate. They had. recorded times and temperatures that should have alerted them to the excessive
- cooldown rate, but failed to recognize and act on the information.
U.S. NUCLEAA ~EGUU.TORY COMMtSSlC'<
19-831 APP'IOVED OMB '<0. 3160-0'0'.
- EXPIRES: 8/31 :86 LICENSEE EVENT REPORT !LERI TEXT CONTINUATION
<.i.CILITY NI.ME 111 DOCKET NUMBER 121 LER NUMBER 131 P.i.GE !'1 SEQUENTIAi. ' REV15'0.N YEM NUMBER NUMBER Palisades Plant 0 5 0 0 0 2 5 5 9 3 - 0 1 0 - 0 0 0 3 c* 0 8 (J)(2)(ii) The error (1) was contrary to an approved procedure in that the PCS cooldown rate defined in the technical specifications and in SOP 1 was exceeded; (2) was aggravated by the procedure in that SOP 1 did not address how the PCS cooldown rate would be affected once the PCPs were removed from servfce, and (3) did not directly result from an activity or task not monitored or covered by the procedure in that the operators could have controlled the cooldown ~sing the guidance in SOP 1. -
(J)(2)(iii) There were no unusual conditions in the work area, the control room, that directly contributed to the error. .
(J)(2)(iv) The individuals involved in this event were licensed reactor operators.
This event_ did not involve the failure of any equipment important to safety.
ANALYSIS OF THE EVENT Prior to this event, a primary cool-ant system (PCS) heat-up was in progress following completion of the 1993 refueling outage activities. During the heat-up, a primary c6olant system (PCS) leak check discovered an uni~olatable leak on top of the pressurizer. *A PCS cool down was commenced in accordance with system operating procedure (SOP) 1, "Primary Coolant System."
The last two operating primary coolant pumps (PCPs) were removed from service in accordance with SOP 1 between 1348 hours0.0156 days <br />0.374 hours <br />0.00223 weeks <br />5.12914e-4 months <br /> and 1356 hours0.0157 days <br />0.377 hours <br />0.00224 weeks <br />5.15958e-4 months <br /> on September 17, 1993, when PCS temperature reached 170~F. Normally, the PCPs are not removed from service at this PCS temperature; however, due to the presence of the leak in the pressurizer, the PCPs were removed from service to permit depressurization of the PCS in an attempt to reduce the leakrate.
The initial evaluation of the event determined that between 1356 hours0.0157 days <br />0.377 hours <br />0.00224 weeks <br />5.15958e-4 months <br /> and 1456 hours0.0169 days <br />0.404 hours <br />0.00241 weeks <br />5.54008e-4 months <br />, immediately following the removal of primary coolant pump P50C from service, the PCS cooldown rate of 20°F in any one hour when the cold leg temperature is less than 170°F, as defined in Technical Specification 3.l.2a, was exceeded. The cooldown rate was calculated in accordance with the existing procedural requirements using the temperature difference between the outlet temperature of the shutdown cooling heat exchanger at 1356 hours0.0157 days <br />0.377 hours <br />0.00224 weeks <br />5.15958e-4 months <br /> and 1456 hours0.0169 days <br />0.404 hours <br />0.00241 weeks <br />5.54008e-4 months <br />. The calculation showed that the PCS temperature had dropped 26°F in that hour using the shutdown cooling heat exchanger outlet temperat~re at the time the PCPs were removed from service as the reference point. An engineering analysis was performed as part of the corrective action for this event and determined that T~olp' at the time the PCPs were removed from service, should be used as the reference point.
Using this previously unrecognized information, the maximum cooldown rate in any one hour was calculated to be 49°F. Based on this new information regarding the use of Tcold
NRC F0tm 3eeA U.S. NUC.lEAA 'IEGUL.>.TORY COMMISSION 19-831 ~OVEO O"'B NO. 316_0-<l'O*
EXP!RES: 813 1:86
. LICENSEE EVENT REPORT !LERI TEXT CONTINUATION FAClllTY NAME 111 DOC.KET NUMBER 121 lER NUMBEJI 131 PAGE 1*1 SEQUENTIAL REVlSION YEAA NUMBER NUMBER Palisades Plant Q 5 Q Q Q 2 5 5 9 3 :- Q 1 Q - Q Q Q 4. OF Q 8 at the time the PCPs were removed frbm service as the. reference point, other previous plant cooldowns were reviewed. We determined that the cooldown rate (using T;old as the reference point following removal of the PCPs from service) _has exceeded the technical
- J specification limit of 20°F/hr on nearly all of the previous cooldowns since the 1.
incorporation of the 20°F/hr limit with Amendment 131 to the Technical Specifications in 1990. . .
This event has also b~en evaluated by the licensed personnel responsible for exceeding the PCS cooldown rate, and, in a9dition, a Human Performance Enhancement System (HPES) evaluation *has been condOcted to determine what human factors may have significantly impacted this event. The results of both of these evaluations with respect to human performance are discussed below.
The evaluations. concluded that while two licensed reactor operators (ROs) had been assigned the responsibility for .the cooldown, both failed to adequately monitor the rate of PCS cooldown. ~actors that contributed to this failure were:
- 1. The pressurizer leak event drew the attention of the operators away from adequately monitoring the PCS ~ooldown rate.
The ROs felt a sense of urgency to depres~urize the PCS to stop the leak. Upon completion of depres*surizing th.e PCS-, a reduction in attentiveness to plant conditions occurred. * *
- 2. Neither ..of the ROs were specifica77y assigne_d nor did either of the ROs assume the responsibility of monitoring PCS cooldown rate following removal from service of the PCPs.
The shift supervisor conducted a pre-job briefing to discuss (1) th~ PCS cooldown, (2) securing. the operating PCPs and charging flow, (3) depressurizing the PCS, and (4) preparing for the PCS drain-down to a level below the leak.
The r.os knew they were responsible for monitoring the PCS cooldown rate but had not communicated the coordination of the activity.
- 3. The shutdown cooling {Sf!C) return temperature indicated on temperature recorder (TR) 0351 increased when the first primary coolant pump was r.emoved from service.
The ROs expected the SOC return temperature to drop when the first PCP was removed from service. Wh~n the ROs noted the temperature increase they felt they could shut down the second PCP with little or no effect on PCS temperature.
The PCS cooldown rate was exceeded when the second PCP was removed from service.
~RC Form 388A U.S. NUCLEAR ~ECiUL)ITQRY COMl*USSIC~
li-131 ...-ovro Ol.lB.NO. 3'60-0'0' EXF'IRES: 8131 *116 LICENSEE EVENT REPORT (LERI TEXT CONTINUATION FACILITY NAME 111 DOCIC.ET NUMBER 121 LER NUMBE!I 131 PAGE 141 SEQUENTIAL REVISION YEM NUMBER NUMBER Palisades Plant 0 5 0 0 0 2 5 5 9 3 - 0 1 0 - 0 0 0 5 Q< 0 8
- 4. Methods for monitoring PCS cooldown, after the primary coolant pumps are removed from service, differs from the method used when the PCPs are in-service.
With the primary coolant system pumps running, the critical functions monitor (CFMS) displays an actual cooldown *rate. *After the PCPs are removed from service, the CFMS generated cooldown rate becomes invalid and TR-0351 is used for monitoring the cooldown rate. TR-0351 digitally displays and records SOC heat exchanger inlet and return temperatures. The cooldown rate must be manually calculated from the TR-0351 readings.
- 5. Lack of supervisory overview.
The SRO failed to adequately monitor the RO actions during the cool down.*
Safety Significance An erigineering evaluation was performed to evaluate the effects of the PCS cooldown of September 17, 1993 with respect to 10CFR50, Appendix G pressure and temperature limits for the Palisades reactor vessel. On September 17, 1993, a maximum cool down rate of 49°F per hour was achieved with the PCS temperature less than or equal to 170°F. The maximum cooldown rate allowed by technical specifications under these conditions is 20°F per hour. The analysis was also used to determine the need to perform an analysis in accordance with the requirements of ASME B&PV Code Section XI, Appendix E.
During the cooldown on September 17, 1993, the following primary coolant system conditions were established:
- PCS pressure was being maintained at approximately 235-270 psia (in the manual mode) when the PCPs were removed from service between 1348 hours0.0156 days <br />0.374 hours <br />0.00223 weeks <br />5.12914e-4 months <br /> and 1356 hours0.0157 days <br />0.377 hours <br />0.00224 weeks <br />5.15958e-4 months <br />.
- At 1410 hours0.0163 days <br />0.392 hours <br />0.00233 weeks <br />5.36505e-4 months <br /> all charging pumps were removed from service eliminating the possibility of mass addition to the PCS.
- At 1413 hours0.0164 days <br />0.393 hours <br />0.00234 weeks <br />5.376465e-4 months <br /> the PCS was depressurized.
- The PCS was cooling down, therefore, there was no pressur~ increase due to swell.
Since all the mass and volume increase terms were either controlled or eliminated during the cooldown of September 17, 1993 the only remaining limit is the 10CFR50, Appendix G, limits.
~RC Form JeeA U.S. NUCLEAA REGUL-'TORY COM .... 155'0<
19*831 APl"IOVED O°"'B NO. 3'60--010*
EXPIRES: 8131.116 LICENSEE EVENT REPORT (LERI TEXT CONTINUATION FACILITY NAME-11 I DOCKE"T NUMBER 121 . LER NUMBER Ill PAGE "'
SEOUENTIAi.. RE\/1SION YEAA NUMBER NUMBER Palisades Plant 0 5 0 0 0 2 5 5 9 3 - 0 1 0 - 0 0 0 6 o* O 8 Table 1 shows the operating limits for the Palisades reactor vessel for fait fluence up to 1.8 El9 N/cm 2 in the lO"F to 200°F temperature range. The data was calculated from equations for the circumferential weld with measurement uncertainty included found from a previous engineering analysis and.is presented graphically in Figure 1. The data preserited differs from the Technical Specification, Figure 3-2, in that Figure 1 accounts for pressure and temperature measurement uncertainties. Consequently, the PT.
limits in Figure 1 are used when evaluating the effe~ts of actual plant operating data.
TABLE 1 - Allowable PCS pressure (psig) for various PCS temoeratures and cooldown rates PCS1Temperature Cool down 10°F 50°F 100°F 150°F 200°F Rate 0 deg/hr 383.8 389.4 402 .8 , 430.4 487.6 20 .deg/hr 325.2 331.1 345.4 374.9 435.8 40 deg/hr 264.9 271. 2 286.5 317.99 383.1 60 deg/hr 199.4 206.1 222.5 256.4 326.3
- 90 deg/hr 139 .1 146.4 163.9 200.1 274.8 100 70.8 78.6 97.5 136.4 216.9 deg/hr Flgln 1
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I As tan be seen on Figure 1, for the short time (approximately 10 minutes) that the PCS was pressurized following trip of the first primary coolant pump (PCS temp = 170°F, pressure= 260.psia (245 psig) or less) a cooldown rate of 60°F/hr can be supported without violating 10CFR50, Appendix G, limits. Following depressurization of the PCS to
'<RC F"'m Jee.o. U.S. NUCLEAA REGUL.o.TORY C:;M ... 1SSlCN li-831 ...-ovro o"'e ><O. 3150.,j"*
EXPIRES: 813 L'86 LICENSEE EVENT REPORT (LERI TEXT CONTINUATION FACILITY NAME 111 DOCIC:ET NUMBER 121 LER NUMBER Ill ?AGE 1'1
- SEQUENTIAL. REVISION YEM NUMBER NUMBER Palisades Plant Q 5 Q Q Q 2 5 .5 9 3 - Q 1 Q - Q Q Q 7 OF 0 8 16 psia, cooldown rates of up to l00°F/hr can be supported without violating 10CFR50, Appendix G, limits.
There are two other margins that have not been taken into account in the low temperature over-pressure protection (LTOP}, 10CFR50, Appendix G, limits in this analysis. First, the 10CFR50, Appendix G, limits have a term accounting for primary coolant pump differential pressure .. This term reduces the allowable indicated pressure for a given*
temperature since the location of pressure measurement is downstream (through the '
reactor internals) from the location of interest (beltline welds). Once the primary coolant pumps are removed from service, the associated flow losses essentially go to zero and the allowed indicated pressure increases. Second, during the September 17, 1993 event, the shutdown cooling system was in service. In the development of the LTOP setpoints, no credit is taken for the relief capacity of the shutdown cooling system relief valve.
The ASME B&PV Code Section XI, Appendix E, provides a methodology for determining the effects of exceeding cooldown limits. Appendix E need only be utilized if heat-up and/-0r cooldown limits have been exceeded during the course of a transient. As indicated earlier in the analysis, no 10CFR50, Appendix G1 limits were exceeded during the cooldown on September 17, 1993, therefore, no Appendix E analysis is necessary.
Conclusion
/' '
Although,the allowed cooldown rat~ of 20°F/hr was exceeded during the September 17, 1993 PCS cooldown, the lOCFR50, Apperidix G, limits pertaining to reactor vessel protection from brittle fracture were not violated. The caltulated maximum cooldown from this event was approximately 49°F/hr; however, cooldown rates up to 60°F/hr can be supported under th~ conditions which existed on September 17, 1993. Following depressurization,
- cooldown rates of up to 100°F/hr can be supported. Since no *heat-up or cooldown limits related to 10CFR50, Appendix G, were violated, an analysis, in accordance with ASME Section XI, Appendii E, is .not necessary.
CORRECTIVE ACTION There are numerous corrective actions associated with this event that are summarized as:
- evaluations of the effect on reactor vessel material as a result of this event and other previous events;
- evaluations and revision of the heat-up and cooldown processes used at Palisades;
- evaluations of procedures and incorporation of identified changes;
- operator training on procedure changes;
NRC F0<m JeeA i.J.S. NUC\.EAA qEGUU.TORY COMMISSION
..* {i-831 -OVEO OMB NO. J\60.¢10*
EXPIRES: 8/J 1 i86 LICENSEE EVENT REPORT (LERI TEXT CONTINUATION FACILITY NAME 111 DOCKET NUMBER 121 lEll NUMBEll 131 PAGE "1 SEQUENTIAL REVISION YEM NUMBEll NUMBER Palisades Plant Q 5 Q Q Q 2 5 5 9 3 - Q 1 Q - Q Q Q 8 CF Q 8
- verificatiori of proper temperature monitoring techniques for heat-up and cool down;
- verification of equipment operation and reliability;
- removal from licensed operator duties pending evaluation for the SRO and ROs d1rectly involved in this event;
- remedial training and simulator perfo~manc~ evaluations of the operating crew
.involved in this event prior to their return to licensed.operator duties;
- discussion with all the operating crews about the implications of this event and similar past events involving personnel error; and
- incorporating the lessons learned from this event into training lesson plans.
ADDITIONAL INFORMATION None