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Category:LICENSEE EVENT REPORT (SEE ALSO AO
MONTHYEARML17335A5641999-10-18018 October 1999 LER 99-024-00:on 990708,literal TS Requirements Were Not Met by Accumlator Valve Surveillance.Caused by Misjudgement Made in Conversion from Initial DC Cook TS to W Std Ts.Submitted License Amend Request.With 991018 Ltr ML17335A5531999-10-0707 October 1999 LER 99-023-00:on 990907,inadequate TS Surveillance Testing of ESW Pump ESF Response Time Noted.Caused by Inadequate Understanding of Plant Design Basis.Surveillance Tests Will Be Revised & Implemented ML17326A1291999-09-17017 September 1999 LER 99-022-00:on 990609,electrical Bus Degraded Voltage Setpoints Too Low for Safety Related Loads,Was Discovered. Caused by Lack of Understanding of Design of Plant.No Immediate Corrective Actions Necessary ML17326A1121999-08-27027 August 1999 LER 99-021-00:on 990728,determined That GL 96-01 Test Requirements Were Not Met in Surveillance Tests.Caused by Failure to Understand Full Extent of GL Requirements. Surveillance Procedures Will Be Revised or Developed ML17326A1011999-08-26026 August 1999 LER 99-020-00:on 990727,EDGs Were Declared Inoperable.Caused by Inadequate Protection of Air Intake,Exhaust & Room Ventilation Structures from Tornado Missile Hazards. Implemented Compensatory Measures in Form of ACs ML17326A0911999-08-16016 August 1999 LER 99-019-00:on 990716,noted Victoreen Containment Hrrms Not Environmentally Qualified to Withstand post-LOCA Conditions.Caused by Inadequate Design Control.Reviewing Options to Support Hrrms Operability in Modes 1-4 ML17326A0771999-08-0404 August 1999 LER 98-029-01:on 980422,noted That Fuel Handling Area Ventilation Sys Was Inoperable.Caused by Original Design Deficiency.Radiological Analysis for Spent Fuel Handling Accidents in Auxiliary Bldg Will Be Redone by 990830 ML17326A0741999-07-29029 July 1999 LER 99-018-00:on 990629,determined That Valve Yokes May Yield Under Combined Stress of Seismic Event & Static,Valve Closed,Stem Thrust.Caused by Inadequate Design of Associated Movs.Operability Determinations Were Performed for Valves ML17326A0661999-07-26026 July 1999 LER 99-017-00:on 990625,noted That Improperly Installed Fuel Oil Return Relief Valve Rendered EDG Inoperable.Caused by Personnel Error.Fuel Oil Return Valve Was Replaced with Valve in Correct Orientation.With 990722 Ltr ML17326A0651999-07-22022 July 1999 LER 98-014-03:on 980310,noted That Response to high-high Containment Pressure Procedure Was Not Consistent with Analysis of Record.Caused by Inadequate Interface with W. FRZ-1 Will Be Revised to Be Consistent with New Analysis ML17326A0491999-07-13013 July 1999 LER 99-016-00:on 990615,TS Requirements for Source Range Neutron Flux Monitors Not Met.Caused by Failure to Understand Design Basis of Plant.Procedures Revised.With 990713 Ltr ML17326A0331999-07-0101 July 1999 LER 99-004-01:on 971030,failure to Perform TS Surveillance Analyses of Reactor Coolant Chemistry with Fuel Removed Was Noted.Caused by Ineffective Mgt of Tss.Chemistry Personnel Have Been Instructed on Requirement to Follow TS as Written ML17326A0151999-06-18018 June 1999 LER 99-014-00:on 990521,determined That Boron Injection Tank Manway Bolts Were Not Included in ISI Program,Creating Missed Exam for Previous ISI Interval.Caused by Programmatic Weakness.Isi Program & Associated ISI Database Modified ML17325B6311999-06-0101 June 1999 LER 99-S03-00:on 990430,vital Area Barrier Degradation Was Noted.Caused by Inadequate Insp & Maint of Vital Area Barrier.Repairs & Mods Were Made to Barriers to Eliminate Degraded & Nonconforming Conditions ML17325B6421999-06-0101 June 1999 LER 99-013-00:on 990327,safety Injection & Centrifugal Charging Throttle Valve Cavitation During LOCA Could Have Led to ECCS Pump Failure.Caused by Inadequate Original Design Application of Si.Throttle Valves Will Be Developed ML17325B6351999-05-28028 May 1999 LER 99-S02-00:on 990428,vulnerability in Safeguard Sys That Could Allow Unauthorized Access to Protected Area Was Noted. Caused by Inadequate Original Plant Design.Mods Were Made to Wall Opening to Eliminate Nonconforming Conditions ML17265A8231999-05-24024 May 1999 LER 98-037-01:on 990422,determined That Ice Condenser Bypass Leakage Exceeds Design Basis Limit.Caused by Pressure Seal Required by Revised W Design Not Incorporated Into Aep Design.Numerous Matl Condition Walkdowns & Assessments Made ML17325B6001999-05-20020 May 1999 LER 99-012-00:on 990420,concluded That Auxiliary Bldg ESF Ventilation Sys Not Capable of Maintaining ESF Room Temps post-accident.Caused by Inadequate Control of Sys Design Inputs.Comprehensive Action Plan Being Developed ML17325B5861999-05-10010 May 1999 LER 99-002-00:on 990415,discovered That TS 4.0.5 Requirements Were Not Met Due to Improperly Performed Test. Caused by Incorrect Interpretation of ASME Code.App J Testing Will Be Completed & Procedures Will Be Revised ML17325B5811999-05-0404 May 1999 LER 99-011-00:on 990407,air Sys for EDG Will Not Support Long Operability.Caused by Original Design Error.Temporary Mod to Supply Makeup Air Capability in Modes 5 & 6 Was Prepared ML17325B5771999-05-0303 May 1999 LER 99-010-00:on 990401,RCS Leak Detection Sys Sensitivity Not in Accordance with Design Requirements Occurred.Caused by Inadequate Original Design of Containment Sump Level. Evaluation Will Be Performed to Clearly Define Design ML17325B5581999-04-16016 April 1999 LER 99-006-00:on 990115,personnel Identified Discrepancy Between TS 3.9.7 Impact Energy Limit & Procedure 12 Ohp 4030.STP.046.Caused by Lack of Design Basis Control.Placed Procedure 12 Ohp 4030.STP.046 on Administrative Hold ML17325B5471999-04-12012 April 1999 LER 99-009-00:on 990304,as-found RHR Safety Relief Valve Lift Setpoint Greater than TS Limit Occurred.Cause Investigation for Condition Has Not Been Completed.Update to LER Will Be Submitted,Upon Completion of Investigation ML17325B5321999-04-0707 April 1999 LER 99-S01-00:on 990308,discovered That Lock for Vital Gate Leading to Plant 4KV Switchgear Area Was Nonconforming & Vulnerable to Unauthorized Access.Caused by Inadequate Gate Design & Inadequate Procedures.Mods Are Being Made to Gate ML17325B5161999-04-0101 April 1999 LER 99-007-00:on 981020,calculations Showed That Divider Barrier Between Upper & Lower Containment Vols Were Overstressed.Engineers Are Currently Working on Analyses of Loads & Stress on Enclosures ML17325B5221999-03-29029 March 1999 LER 99-001-00:on 960610,degraded Component Cooling Water Flow to Containment Main Steam Line Penetrations,Identified on 990226.Caused by Inadequate Understanding of Design Basis.Additional Investigations Ongoing ML17325B4801999-03-18018 March 1999 LER 99-004-00:on 971030,failure to Perform TS Surveillance Analyses of Rc Chemistry with Fuel Removed Was Noted.Cause of Event Is Under Investigation.Corrected Written Job Order Activities Used to Control SD Chemistry Sampling ML17325B4741999-03-18018 March 1999 LER 99-005-00:on 940512,determined That Rt Breaker Manual Actuations During Rod Drop Testing Were Not Previously Reported.Caused by Lack of Training.Addl Corrective Actions,Including Preventative Actions May Be Developed ML17325B4571999-02-24024 February 1999 LER 99-003-00:on 990107,CR Pressurization Sys Surveillance Test Did Not Test Sys in Normal Operating Condition.Caused by Failure to Recognize Door 12DR-AUX415 as Part of CR Pressure Boundary.Performed Walkdown of Other Doors ML17335A5171999-02-11011 February 1999 LER 99-002-00:on 990112,determined That RCS Pressurizer PORVs Had Not Been Tested,Per Ts.Caused by Inadequate Scheduling Controls Allowing Personnel Error.Surveillance Procedure Was Completed & Updated LER Will Be Submitted ML17335A5141999-02-10010 February 1999 LER 99-001-00:on 990106,noted That GE Hfa Relays Installed in EDGs May Not Meet Seismic Qualification.Caused by Operating Experience Info Incorrectly Dispositioned in 1985. Updated LER Will Be Submitted by 990405 ML17335A5011999-02-0101 February 1999 LER 98-060-00:on 981231,identified That Rt Sys Response Time Testing Did Not Comply with TS Definition.Caused by Inadequate Procedures.Corrective Actions Will Be Developed & Update to LER Will Be Submitted by 990415.With 990201 Ltr ML17335A4951999-01-29029 January 1999 LER 98-059-00:on 981230,interim LER -single Failure in Containment Spray Sys Could Result in Containment Spray Ph Outside Design Occurred.Investigation Into Condition Continuing.Update Will Be Submitted by 990514 Ltr ML17335A4961999-01-27027 January 1999 LER 98-057-00:on 981228,discovered That AFW Valves Were Not Tested IAW Inservice Testing Program.Caused by Failure to Recognize Design Bases Features Re Afws by Personnel. Updated LER Will Be Submittted by 990415.With 990127 Ltr ML17335A4921999-01-19019 January 1999 LER 98-052-01:on 981128,no Analysis for NSR Sc Manual Loader for Tdafwp Could Be Found in Original Design.Cause Due to All Failure Modes Not Considered When Compressed Air Sys Originally Designed.Performed Review of Components ML17335A4721999-01-0606 January 1999 LER 98-055-00:on 981207,potential for Condition Outside of Design Bases for Rod Control Sys Was Noted.Caused by Calibration Error Coupled with Single Rod Failure.Condition Rept Investigation Is Ongoing ML17335A4691999-01-0606 January 1999 LER 98-056-00:on 981211,hot Leg Nozzle Gaps Resulted in Plant Being in Unanalyzed Condition.Analyses Are Being Performed by W to Resolve Problem.Updated LER Will Be Submitted by 990211.With 990106 Ltr ML17335A4661999-01-0505 January 1999 LER 98-049-00:on 981020,emergency Boron Injection Flow Path Was Inoperable.Caused by Original Design Deficiency. Engineering Evaluation of Event Is Continuing ML17335A4631999-01-0404 January 1999 LER 98-054-00:on 981202,discovered That at Least One MSSV Had Not Been Reset as Required by Ts.Engineering Is Continuing Review of Extent of Condition for Event.Updated LER Will Be Submitted by 990129.With 990104 Ltr ML17335A4481998-12-30030 December 1998 LER 98-053-00:on 981130,discovered Use of Inoperable Substitute Subcooling Margin Monitor.Caused by Condition Existing Since Installation of Plant Process Computer in 1992.Updated LER Will Be Submitted.With 981230 Ltr ML17335A4581998-12-28028 December 1998 LER 98-052-00:on 981128,turbine Driven AFW Pump Speed Controller Failure Mode Occurred.Caused Because Not All Failure Modes Were Considered When Compressed Air Sys Was Originally Designed.Verified Current Design Change Process ML17335A4281998-12-22022 December 1998 LER 98-051-00:on 981122,reactor Trip Signal from Manual Safety Injection Not Verified as Required by TS Surveillance,Was Discovered.Maintenance Currently Evaluating Significance & Cause of Event ML17335A4111998-12-17017 December 1998 LER 98-047-00:on 981117,potential for Increase Leakage from Reactor Coolant Pump Seals Was Identified.Util Is Working with W to Resolve Issue.Current Expectations Are to Submit Update to LER by 990215.With 981217 Ltr ML17335A4141998-12-16016 December 1998 LER 98-058-00:on 981216,postulated High Line Break Could Result in Condition Outside Design Bases for AF Occurred. Caused by Deficiencies Associated with Administration of HELB Program.Analysis of AF Will Be Completed by 990122 ML17335A4181998-12-16016 December 1998 LER 98-050-00:on 980814,ancillary Equipment Installed in Ice Condenser Was Not Designed to Withstand Design Basis Accident/Earthquake Loads.Caused by Lack of Established Design Criteria.Developed Design Criteria ML17335A3871998-12-11011 December 1998 LER 98-031-01:on 980610,potential Common Mode Failure of RHR Pumps Were Noted.Caused by Inaccurate Values.Accurate Miniflow Numbers Have Been Determined by Flow Testing ML17335A3821998-12-0808 December 1998 LER 98-039-01 Re EOP Step Conflicts with Small Break LOCA Analysis.Ler 98-039-00 Has Been Canceled.With 981208 Ltr ML17335A3781998-12-0707 December 1998 LER 98-007-00:on 981106,high Energy Line Break Effects in Auxiliary FW Sys Was Noted.Cause of Event Is Under Investigation & Will Be Completed by 990220.Updated LER Will Be Submitted by 990310.With 981207 Ltr ML17335A3771998-12-0303 December 1998 LER 98-046-00:on 981103,determined That Afs Was Unable to Meet Design Flow Requirements During Special Test.Caused by Failure to Consider All Aspects of Sys Operation in Design of Suction Basket Strainers.Sys Will Be Redesigned ML17335A3741998-12-0202 December 1998 LER 97-011-02:on 970822,operation Was Noted Outside Design Bases for ECCS & CSP for Switchover to Recirculation Sump Suction.Caused by Ineffective Change Mgt.Revised Procedure for Switchover 01(02) Ohp 4023.ES-1.3 1999-09-17
[Table view] Category:RO)
MONTHYEARML17335A5641999-10-18018 October 1999 LER 99-024-00:on 990708,literal TS Requirements Were Not Met by Accumlator Valve Surveillance.Caused by Misjudgement Made in Conversion from Initial DC Cook TS to W Std Ts.Submitted License Amend Request.With 991018 Ltr ML17335A5531999-10-0707 October 1999 LER 99-023-00:on 990907,inadequate TS Surveillance Testing of ESW Pump ESF Response Time Noted.Caused by Inadequate Understanding of Plant Design Basis.Surveillance Tests Will Be Revised & Implemented ML17326A1291999-09-17017 September 1999 LER 99-022-00:on 990609,electrical Bus Degraded Voltage Setpoints Too Low for Safety Related Loads,Was Discovered. Caused by Lack of Understanding of Design of Plant.No Immediate Corrective Actions Necessary ML17326A1121999-08-27027 August 1999 LER 99-021-00:on 990728,determined That GL 96-01 Test Requirements Were Not Met in Surveillance Tests.Caused by Failure to Understand Full Extent of GL Requirements. Surveillance Procedures Will Be Revised or Developed ML17326A1011999-08-26026 August 1999 LER 99-020-00:on 990727,EDGs Were Declared Inoperable.Caused by Inadequate Protection of Air Intake,Exhaust & Room Ventilation Structures from Tornado Missile Hazards. Implemented Compensatory Measures in Form of ACs ML17326A0911999-08-16016 August 1999 LER 99-019-00:on 990716,noted Victoreen Containment Hrrms Not Environmentally Qualified to Withstand post-LOCA Conditions.Caused by Inadequate Design Control.Reviewing Options to Support Hrrms Operability in Modes 1-4 ML17326A0771999-08-0404 August 1999 LER 98-029-01:on 980422,noted That Fuel Handling Area Ventilation Sys Was Inoperable.Caused by Original Design Deficiency.Radiological Analysis for Spent Fuel Handling Accidents in Auxiliary Bldg Will Be Redone by 990830 ML17326A0741999-07-29029 July 1999 LER 99-018-00:on 990629,determined That Valve Yokes May Yield Under Combined Stress of Seismic Event & Static,Valve Closed,Stem Thrust.Caused by Inadequate Design of Associated Movs.Operability Determinations Were Performed for Valves ML17326A0661999-07-26026 July 1999 LER 99-017-00:on 990625,noted That Improperly Installed Fuel Oil Return Relief Valve Rendered EDG Inoperable.Caused by Personnel Error.Fuel Oil Return Valve Was Replaced with Valve in Correct Orientation.With 990722 Ltr ML17326A0651999-07-22022 July 1999 LER 98-014-03:on 980310,noted That Response to high-high Containment Pressure Procedure Was Not Consistent with Analysis of Record.Caused by Inadequate Interface with W. FRZ-1 Will Be Revised to Be Consistent with New Analysis ML17326A0491999-07-13013 July 1999 LER 99-016-00:on 990615,TS Requirements for Source Range Neutron Flux Monitors Not Met.Caused by Failure to Understand Design Basis of Plant.Procedures Revised.With 990713 Ltr ML17326A0331999-07-0101 July 1999 LER 99-004-01:on 971030,failure to Perform TS Surveillance Analyses of Reactor Coolant Chemistry with Fuel Removed Was Noted.Caused by Ineffective Mgt of Tss.Chemistry Personnel Have Been Instructed on Requirement to Follow TS as Written ML17326A0151999-06-18018 June 1999 LER 99-014-00:on 990521,determined That Boron Injection Tank Manway Bolts Were Not Included in ISI Program,Creating Missed Exam for Previous ISI Interval.Caused by Programmatic Weakness.Isi Program & Associated ISI Database Modified ML17325B6311999-06-0101 June 1999 LER 99-S03-00:on 990430,vital Area Barrier Degradation Was Noted.Caused by Inadequate Insp & Maint of Vital Area Barrier.Repairs & Mods Were Made to Barriers to Eliminate Degraded & Nonconforming Conditions ML17325B6421999-06-0101 June 1999 LER 99-013-00:on 990327,safety Injection & Centrifugal Charging Throttle Valve Cavitation During LOCA Could Have Led to ECCS Pump Failure.Caused by Inadequate Original Design Application of Si.Throttle Valves Will Be Developed ML17325B6351999-05-28028 May 1999 LER 99-S02-00:on 990428,vulnerability in Safeguard Sys That Could Allow Unauthorized Access to Protected Area Was Noted. Caused by Inadequate Original Plant Design.Mods Were Made to Wall Opening to Eliminate Nonconforming Conditions ML17265A8231999-05-24024 May 1999 LER 98-037-01:on 990422,determined That Ice Condenser Bypass Leakage Exceeds Design Basis Limit.Caused by Pressure Seal Required by Revised W Design Not Incorporated Into Aep Design.Numerous Matl Condition Walkdowns & Assessments Made ML17325B6001999-05-20020 May 1999 LER 99-012-00:on 990420,concluded That Auxiliary Bldg ESF Ventilation Sys Not Capable of Maintaining ESF Room Temps post-accident.Caused by Inadequate Control of Sys Design Inputs.Comprehensive Action Plan Being Developed ML17325B5861999-05-10010 May 1999 LER 99-002-00:on 990415,discovered That TS 4.0.5 Requirements Were Not Met Due to Improperly Performed Test. Caused by Incorrect Interpretation of ASME Code.App J Testing Will Be Completed & Procedures Will Be Revised ML17325B5811999-05-0404 May 1999 LER 99-011-00:on 990407,air Sys for EDG Will Not Support Long Operability.Caused by Original Design Error.Temporary Mod to Supply Makeup Air Capability in Modes 5 & 6 Was Prepared ML17325B5771999-05-0303 May 1999 LER 99-010-00:on 990401,RCS Leak Detection Sys Sensitivity Not in Accordance with Design Requirements Occurred.Caused by Inadequate Original Design of Containment Sump Level. Evaluation Will Be Performed to Clearly Define Design ML17325B5581999-04-16016 April 1999 LER 99-006-00:on 990115,personnel Identified Discrepancy Between TS 3.9.7 Impact Energy Limit & Procedure 12 Ohp 4030.STP.046.Caused by Lack of Design Basis Control.Placed Procedure 12 Ohp 4030.STP.046 on Administrative Hold ML17325B5471999-04-12012 April 1999 LER 99-009-00:on 990304,as-found RHR Safety Relief Valve Lift Setpoint Greater than TS Limit Occurred.Cause Investigation for Condition Has Not Been Completed.Update to LER Will Be Submitted,Upon Completion of Investigation ML17325B5321999-04-0707 April 1999 LER 99-S01-00:on 990308,discovered That Lock for Vital Gate Leading to Plant 4KV Switchgear Area Was Nonconforming & Vulnerable to Unauthorized Access.Caused by Inadequate Gate Design & Inadequate Procedures.Mods Are Being Made to Gate ML17325B5161999-04-0101 April 1999 LER 99-007-00:on 981020,calculations Showed That Divider Barrier Between Upper & Lower Containment Vols Were Overstressed.Engineers Are Currently Working on Analyses of Loads & Stress on Enclosures ML17325B5221999-03-29029 March 1999 LER 99-001-00:on 960610,degraded Component Cooling Water Flow to Containment Main Steam Line Penetrations,Identified on 990226.Caused by Inadequate Understanding of Design Basis.Additional Investigations Ongoing ML17325B4801999-03-18018 March 1999 LER 99-004-00:on 971030,failure to Perform TS Surveillance Analyses of Rc Chemistry with Fuel Removed Was Noted.Cause of Event Is Under Investigation.Corrected Written Job Order Activities Used to Control SD Chemistry Sampling ML17325B4741999-03-18018 March 1999 LER 99-005-00:on 940512,determined That Rt Breaker Manual Actuations During Rod Drop Testing Were Not Previously Reported.Caused by Lack of Training.Addl Corrective Actions,Including Preventative Actions May Be Developed ML17325B4571999-02-24024 February 1999 LER 99-003-00:on 990107,CR Pressurization Sys Surveillance Test Did Not Test Sys in Normal Operating Condition.Caused by Failure to Recognize Door 12DR-AUX415 as Part of CR Pressure Boundary.Performed Walkdown of Other Doors ML17335A5171999-02-11011 February 1999 LER 99-002-00:on 990112,determined That RCS Pressurizer PORVs Had Not Been Tested,Per Ts.Caused by Inadequate Scheduling Controls Allowing Personnel Error.Surveillance Procedure Was Completed & Updated LER Will Be Submitted ML17335A5141999-02-10010 February 1999 LER 99-001-00:on 990106,noted That GE Hfa Relays Installed in EDGs May Not Meet Seismic Qualification.Caused by Operating Experience Info Incorrectly Dispositioned in 1985. Updated LER Will Be Submitted by 990405 ML17335A5011999-02-0101 February 1999 LER 98-060-00:on 981231,identified That Rt Sys Response Time Testing Did Not Comply with TS Definition.Caused by Inadequate Procedures.Corrective Actions Will Be Developed & Update to LER Will Be Submitted by 990415.With 990201 Ltr ML17335A4951999-01-29029 January 1999 LER 98-059-00:on 981230,interim LER -single Failure in Containment Spray Sys Could Result in Containment Spray Ph Outside Design Occurred.Investigation Into Condition Continuing.Update Will Be Submitted by 990514 Ltr ML17335A4961999-01-27027 January 1999 LER 98-057-00:on 981228,discovered That AFW Valves Were Not Tested IAW Inservice Testing Program.Caused by Failure to Recognize Design Bases Features Re Afws by Personnel. Updated LER Will Be Submittted by 990415.With 990127 Ltr ML17335A4921999-01-19019 January 1999 LER 98-052-01:on 981128,no Analysis for NSR Sc Manual Loader for Tdafwp Could Be Found in Original Design.Cause Due to All Failure Modes Not Considered When Compressed Air Sys Originally Designed.Performed Review of Components ML17335A4721999-01-0606 January 1999 LER 98-055-00:on 981207,potential for Condition Outside of Design Bases for Rod Control Sys Was Noted.Caused by Calibration Error Coupled with Single Rod Failure.Condition Rept Investigation Is Ongoing ML17335A4691999-01-0606 January 1999 LER 98-056-00:on 981211,hot Leg Nozzle Gaps Resulted in Plant Being in Unanalyzed Condition.Analyses Are Being Performed by W to Resolve Problem.Updated LER Will Be Submitted by 990211.With 990106 Ltr ML17335A4661999-01-0505 January 1999 LER 98-049-00:on 981020,emergency Boron Injection Flow Path Was Inoperable.Caused by Original Design Deficiency. Engineering Evaluation of Event Is Continuing ML17335A4631999-01-0404 January 1999 LER 98-054-00:on 981202,discovered That at Least One MSSV Had Not Been Reset as Required by Ts.Engineering Is Continuing Review of Extent of Condition for Event.Updated LER Will Be Submitted by 990129.With 990104 Ltr ML17335A4481998-12-30030 December 1998 LER 98-053-00:on 981130,discovered Use of Inoperable Substitute Subcooling Margin Monitor.Caused by Condition Existing Since Installation of Plant Process Computer in 1992.Updated LER Will Be Submitted.With 981230 Ltr ML17335A4581998-12-28028 December 1998 LER 98-052-00:on 981128,turbine Driven AFW Pump Speed Controller Failure Mode Occurred.Caused Because Not All Failure Modes Were Considered When Compressed Air Sys Was Originally Designed.Verified Current Design Change Process ML17335A4281998-12-22022 December 1998 LER 98-051-00:on 981122,reactor Trip Signal from Manual Safety Injection Not Verified as Required by TS Surveillance,Was Discovered.Maintenance Currently Evaluating Significance & Cause of Event ML17335A4111998-12-17017 December 1998 LER 98-047-00:on 981117,potential for Increase Leakage from Reactor Coolant Pump Seals Was Identified.Util Is Working with W to Resolve Issue.Current Expectations Are to Submit Update to LER by 990215.With 981217 Ltr ML17335A4141998-12-16016 December 1998 LER 98-058-00:on 981216,postulated High Line Break Could Result in Condition Outside Design Bases for AF Occurred. Caused by Deficiencies Associated with Administration of HELB Program.Analysis of AF Will Be Completed by 990122 ML17335A4181998-12-16016 December 1998 LER 98-050-00:on 980814,ancillary Equipment Installed in Ice Condenser Was Not Designed to Withstand Design Basis Accident/Earthquake Loads.Caused by Lack of Established Design Criteria.Developed Design Criteria ML17335A3871998-12-11011 December 1998 LER 98-031-01:on 980610,potential Common Mode Failure of RHR Pumps Were Noted.Caused by Inaccurate Values.Accurate Miniflow Numbers Have Been Determined by Flow Testing ML17335A3821998-12-0808 December 1998 LER 98-039-01 Re EOP Step Conflicts with Small Break LOCA Analysis.Ler 98-039-00 Has Been Canceled.With 981208 Ltr ML17335A3781998-12-0707 December 1998 LER 98-007-00:on 981106,high Energy Line Break Effects in Auxiliary FW Sys Was Noted.Cause of Event Is Under Investigation & Will Be Completed by 990220.Updated LER Will Be Submitted by 990310.With 981207 Ltr ML17335A3771998-12-0303 December 1998 LER 98-046-00:on 981103,determined That Afs Was Unable to Meet Design Flow Requirements During Special Test.Caused by Failure to Consider All Aspects of Sys Operation in Design of Suction Basket Strainers.Sys Will Be Redesigned ML17335A3741998-12-0202 December 1998 LER 97-011-02:on 970822,operation Was Noted Outside Design Bases for ECCS & CSP for Switchover to Recirculation Sump Suction.Caused by Ineffective Change Mgt.Revised Procedure for Switchover 01(02) Ohp 4023.ES-1.3 1999-09-17
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML17335A5641999-10-18018 October 1999 LER 99-024-00:on 990708,literal TS Requirements Were Not Met by Accumlator Valve Surveillance.Caused by Misjudgement Made in Conversion from Initial DC Cook TS to W Std Ts.Submitted License Amend Request.With 991018 Ltr ML17335A5531999-10-0707 October 1999 LER 99-023-00:on 990907,inadequate TS Surveillance Testing of ESW Pump ESF Response Time Noted.Caused by Inadequate Understanding of Plant Design Basis.Surveillance Tests Will Be Revised & Implemented ML17335A5631999-09-30030 September 1999 Monthly Operating Rept for Sept 1999 for DC Cook Nuclear Plant,Unit 1.With 991012 Ltr ML17335A5621999-09-30030 September 1999 Monthly Operating Rept for Sept 1999 for DC Cook Nuclear Plant,Unit 2.With 991012 Ltr ML17335A5481999-09-30030 September 1999 Non-proprietary DC Cook Nuclear Plant Units 1 & 2 Mods to Containment Sys W SE (Secl 99-076,Rev 3). ML17335A5451999-09-28028 September 1999 Rev 1 to Containment Sump Level Design Condition & Failure Effects Analysis for Potential Draindown Scenarios. ML17326A1291999-09-17017 September 1999 LER 99-022-00:on 990609,electrical Bus Degraded Voltage Setpoints Too Low for Safety Related Loads,Was Discovered. Caused by Lack of Understanding of Design of Plant.No Immediate Corrective Actions Necessary ML17326A1481999-09-17017 September 1999 Independent Review of Control Rod Insertion Following Cold Leg Lbloca,Dc Cook,Units 1 & 2. ML17326A1211999-08-31031 August 1999 Monthly Operating Rept for Aug 1999 for Cook Nuclear Plant, Unit 2.With 990915 Ltr ML17326A1201999-08-31031 August 1999 Monthly Operating Rept for Aug 1999 for Cook Nuclear Plant, Unit 1.With 990915 Ltr ML17326A1121999-08-27027 August 1999 LER 99-021-00:on 990728,determined That GL 96-01 Test Requirements Were Not Met in Surveillance Tests.Caused by Failure to Understand Full Extent of GL Requirements. Surveillance Procedures Will Be Revised or Developed ML17326A1011999-08-26026 August 1999 LER 99-020-00:on 990727,EDGs Were Declared Inoperable.Caused by Inadequate Protection of Air Intake,Exhaust & Room Ventilation Structures from Tornado Missile Hazards. Implemented Compensatory Measures in Form of ACs ML17326A0911999-08-16016 August 1999 LER 99-019-00:on 990716,noted Victoreen Containment Hrrms Not Environmentally Qualified to Withstand post-LOCA Conditions.Caused by Inadequate Design Control.Reviewing Options to Support Hrrms Operability in Modes 1-4 ML17326A0771999-08-0404 August 1999 LER 98-029-01:on 980422,noted That Fuel Handling Area Ventilation Sys Was Inoperable.Caused by Original Design Deficiency.Radiological Analysis for Spent Fuel Handling Accidents in Auxiliary Bldg Will Be Redone by 990830 ML17335A5461999-08-0202 August 1999 Rev 0 to Evaluation of Cook Recirculation Sump Level for Reduced Pump Flow Rates. ML17326A0871999-07-31031 July 1999 Monthly Operating Rept for July 1999 for DC Cook Nuclear Plant,Unit 1.With 990812 Ltr ML17326A0861999-07-31031 July 1999 Monthly Operating Rept for July 1999 for DC Cook Nuclear Plant,Units 2.With 990812 Ltr ML17326A0741999-07-29029 July 1999 LER 99-018-00:on 990629,determined That Valve Yokes May Yield Under Combined Stress of Seismic Event & Static,Valve Closed,Stem Thrust.Caused by Inadequate Design of Associated Movs.Operability Determinations Were Performed for Valves ML17326A0661999-07-26026 July 1999 LER 99-017-00:on 990625,noted That Improperly Installed Fuel Oil Return Relief Valve Rendered EDG Inoperable.Caused by Personnel Error.Fuel Oil Return Valve Was Replaced with Valve in Correct Orientation.With 990722 Ltr ML17326A0651999-07-22022 July 1999 LER 98-014-03:on 980310,noted That Response to high-high Containment Pressure Procedure Was Not Consistent with Analysis of Record.Caused by Inadequate Interface with W. FRZ-1 Will Be Revised to Be Consistent with New Analysis ML17326A0491999-07-13013 July 1999 LER 99-016-00:on 990615,TS Requirements for Source Range Neutron Flux Monitors Not Met.Caused by Failure to Understand Design Basis of Plant.Procedures Revised.With 990713 Ltr ML17326A0331999-07-0101 July 1999 LER 99-004-01:on 971030,failure to Perform TS Surveillance Analyses of Reactor Coolant Chemistry with Fuel Removed Was Noted.Caused by Ineffective Mgt of Tss.Chemistry Personnel Have Been Instructed on Requirement to Follow TS as Written ML17326A0511999-06-30030 June 1999 Monthly Operating Rept for June 1999 for DC Cook Nuclear Plant,Unit 2.With 990709 Ltr ML17326A0501999-06-30030 June 1999 Monthly Operating Rept for June 1999 for DC Cook Nuclear Plant,Unit 1.With 990709 Ltr ML17326A0151999-06-18018 June 1999 LER 99-014-00:on 990521,determined That Boron Injection Tank Manway Bolts Were Not Included in ISI Program,Creating Missed Exam for Previous ISI Interval.Caused by Programmatic Weakness.Isi Program & Associated ISI Database Modified ML17325B6421999-06-0101 June 1999 LER 99-013-00:on 990327,safety Injection & Centrifugal Charging Throttle Valve Cavitation During LOCA Could Have Led to ECCS Pump Failure.Caused by Inadequate Original Design Application of Si.Throttle Valves Will Be Developed ML17325B6311999-06-0101 June 1999 LER 99-S03-00:on 990430,vital Area Barrier Degradation Was Noted.Caused by Inadequate Insp & Maint of Vital Area Barrier.Repairs & Mods Were Made to Barriers to Eliminate Degraded & Nonconforming Conditions ML17326A0061999-05-31031 May 1999 Monthly Operating Rept for May 1999 for Dcp.With 990609 Ltr ML17326A0071999-05-31031 May 1999 Monthly Operating Rept for May 1999 for DC Cook Nuclear Plant,Unit 2.With 990609 Ltr ML17325B6351999-05-28028 May 1999 LER 99-S02-00:on 990428,vulnerability in Safeguard Sys That Could Allow Unauthorized Access to Protected Area Was Noted. Caused by Inadequate Original Plant Design.Mods Were Made to Wall Opening to Eliminate Nonconforming Conditions ML17265A8231999-05-24024 May 1999 LER 98-037-01:on 990422,determined That Ice Condenser Bypass Leakage Exceeds Design Basis Limit.Caused by Pressure Seal Required by Revised W Design Not Incorporated Into Aep Design.Numerous Matl Condition Walkdowns & Assessments Made ML17325B6001999-05-20020 May 1999 LER 99-012-00:on 990420,concluded That Auxiliary Bldg ESF Ventilation Sys Not Capable of Maintaining ESF Room Temps post-accident.Caused by Inadequate Control of Sys Design Inputs.Comprehensive Action Plan Being Developed ML17325B5861999-05-10010 May 1999 LER 99-002-00:on 990415,discovered That TS 4.0.5 Requirements Were Not Met Due to Improperly Performed Test. Caused by Incorrect Interpretation of ASME Code.App J Testing Will Be Completed & Procedures Will Be Revised ML17325B5811999-05-0404 May 1999 LER 99-011-00:on 990407,air Sys for EDG Will Not Support Long Operability.Caused by Original Design Error.Temporary Mod to Supply Makeup Air Capability in Modes 5 & 6 Was Prepared ML17325B5771999-05-0303 May 1999 LER 99-010-00:on 990401,RCS Leak Detection Sys Sensitivity Not in Accordance with Design Requirements Occurred.Caused by Inadequate Original Design of Containment Sump Level. Evaluation Will Be Performed to Clearly Define Design ML17335A5301999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for DC Cook Nuclear Plant,Unit 1.With 990508 Ltr ML17335A5291999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for DC Cook Nuclear Plant,Unit 2.With 990508 Ltr ML17325B5581999-04-16016 April 1999 LER 99-006-00:on 990115,personnel Identified Discrepancy Between TS 3.9.7 Impact Energy Limit & Procedure 12 Ohp 4030.STP.046.Caused by Lack of Design Basis Control.Placed Procedure 12 Ohp 4030.STP.046 on Administrative Hold ML17325B5471999-04-12012 April 1999 LER 99-009-00:on 990304,as-found RHR Safety Relief Valve Lift Setpoint Greater than TS Limit Occurred.Cause Investigation for Condition Has Not Been Completed.Update to LER Will Be Submitted,Upon Completion of Investigation ML17325B5321999-04-0707 April 1999 LER 99-S01-00:on 990308,discovered That Lock for Vital Gate Leading to Plant 4KV Switchgear Area Was Nonconforming & Vulnerable to Unauthorized Access.Caused by Inadequate Gate Design & Inadequate Procedures.Mods Are Being Made to Gate ML17325B5161999-04-0101 April 1999 LER 99-007-00:on 981020,calculations Showed That Divider Barrier Between Upper & Lower Containment Vols Were Overstressed.Engineers Are Currently Working on Analyses of Loads & Stress on Enclosures ML17325B5491999-03-31031 March 1999 Monthly Operating Rept for Mar 1999 for DC Cook Nuclear Plant Unit 2.With 990408 Ltr ML17325B5441999-03-31031 March 1999 Monthly Operating Rept for Mar 1999 for DC Cook Nuclear Plant,Unit 1.With 990408 Ltr ML17325B5221999-03-29029 March 1999 LER 99-001-00:on 960610,degraded Component Cooling Water Flow to Containment Main Steam Line Penetrations,Identified on 990226.Caused by Inadequate Understanding of Design Basis.Additional Investigations Ongoing ML17325B4801999-03-18018 March 1999 LER 99-004-00:on 971030,failure to Perform TS Surveillance Analyses of Rc Chemistry with Fuel Removed Was Noted.Cause of Event Is Under Investigation.Corrected Written Job Order Activities Used to Control SD Chemistry Sampling ML17325B4741999-03-18018 March 1999 LER 99-005-00:on 940512,determined That Rt Breaker Manual Actuations During Rod Drop Testing Were Not Previously Reported.Caused by Lack of Training.Addl Corrective Actions,Including Preventative Actions May Be Developed ML17325B5671999-03-0202 March 1999 Summary of Unit 1 Steam Generator Layup Chemistry from 980101 to 990218. ML17325B4631999-02-28028 February 1999 Monthly Operating Rept for Feb 1999 for DC Cook Nuclear Power Station,Unit 2.With 990308 Ltr ML17325B4621999-02-28028 February 1999 Monthly Operating Rept for Feb 1999 for DC Cook Nuclear Plant,Unit 1.With 990308 Ltr ML17325B4571999-02-24024 February 1999 LER 99-003-00:on 990107,CR Pressurization Sys Surveillance Test Did Not Test Sys in Normal Operating Condition.Caused by Failure to Recognize Door 12DR-AUX415 as Part of CR Pressure Boundary.Performed Walkdown of Other Doors 1999-09-30
[Table view] |
Text
ACCELERATED UTION DEMONS'ATION SYSTEM REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)
ACCESSION NBR:9007020032 DOC.DATE: 90/06/22 NOTARIZED: NO DOCKET FACIL:50-316 Donald C. Cook Nuclear Power Plant, Unit 2, Indiana & 05000316 AUTH. NAME AUTHOR AFFILIATION BEILMAN,T.P. Indiana Michigan Power Co. (formerly Indiana & Michigan Ele BLIND,A.A. Indiana Michigan Power Co. (formerly Indiana & Michigan Ele RECIP.NAME RECIPIENT AFFILIATION
SUBJECT:
LER 88-003-08:on 880111,repetitive violation of ESF instrumentation LCO tolerances due to highly RA values.
W/9 DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR ENCL SIZE:
TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.
NOTES:
RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ' ID CODE/NAME LTTR ENCL PD3-1 LA 1 1 PD3-1 PD 1 1 GIITTER,J. 1 INTERNAL: ACNW 2 2 AEOD/DOA 1' AEOD/DS P/TPAB 1 1 AEOD/ROAB/DS P 2 2 DEDRO 1 1 NRR/DET/ECMB 9H 1 1 NRR/DET/EMEB9H3 1 1 NRR/DLPQ/LHFB11 1 1 NRR/DLPQ/LPEB10 1 1 NRR/DOEA/OEAB11 1 1 NRR/DREP/PRPB11 2 2 NRR/DST/SELB 8D 1 1 NRR/DST/SICB 7E 1 1 LB8D1 1 1 NRR/DST/SRXB 8E 1 1 EG FILE 02 1 1 RES/DSIR/EIB 1 1 01 1 1 EXTERNAL: EG&G STUART,V.A 4 4 L ST LOBBY WARD 1 1 LPDR 1 1 NRC PDR 1 1 NSIC MAYS,G 1 1 NSIC MURPHY,G.A 1 1 NUDOCS FULL TXT 1 1 NOTE TO ALL "RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOM Pl-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 34 ENCL 34
Indiana Michigan Power Company Cook Nuclear Plant P.O. Box 458 Bridgman. Ml 49106 616 465 5901 INDIANA NfCHIGiAN POWER June 22, 1990 United States Nuclear Regulatory Commission Document Control Desk Rockville, Maryland 20852 Operating Licenses DPR-58 Docket No. 50-316 Document Control Manager:
In accordance with the criteria established by 10 CFR 50.73 entitled Licensee Event Re ortin S stem, the following report is being submitted:
88-003-08 Sincerely, A.A. Blind
~ ~
Plant Manager AAB:clw Attachment CC D.H. Williams, Jr.
A.B. Davis, Region III M.P. Alexich P.A. Barrett J.E. Borggren R.F. Kroeger B. Walters Ft. Wayne NRC Resident Inspector J.G. Giitter, NRC J.G. Keppler M.R. Padgett G. Charnoff, Esp.
Dottie Sherman, ANI Library D. Hahn INPO S.J. Brewer/B.P. Lauzau W(pg 9OO/O2QQ I- Di~
i 9t. Cyr'..";
< )" i(iC)O>> j qq II
NRC FORM 366 V.S. NUCLEAR REGULATORY COMMISSION (569) APPROVED OMB NO,31500104 EXPIRES: 4/30/92 ESTIMATED BURDEN PER RESPONSE TO COMPLY WTH THIS INFORMATION COLLECTION REQUESTt 500 HRS. FORWARD LICENSEE EVENT REPORT ILER) COMMENTS REGARDING BURDEN ESTIMATE TO THF. RECORDS ANO REPORTS MANAGEMENT BRANCH (F630>, U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON. OC 20555, AND TO THE PAPERWORK REDUCTION PROJECT (31500104). OFFICE OF MANAGEMENTANO BUDGET,WASHINGTON, OC20503.
FACILITY NAME (I) DOCKET NUMBER (ll PA D. C. COOK NUCLEAR PLANT - UNIT 2 0 5 0 0 03 ] 6 1 OF0 REPETITIVE VIOLATION OF ESF INSTRUMENTATION LIMITING CONDITIONS FOR OPERATION TOLERANCES DUE TO HIGHLY RESTRICTIVE ALLOWABLE VALUES EVENT DATE(5) LER NUMBER (6) REPORT DATE (TI OTHER FACILITIES INVOLVED (Sl MOIITH OAY YEAR YKAR SEOUENTIAI :rvor','EVtSK MON'TH OAY YEAR FACILITYNAMES DOCKET NUMBER(5)
NVMBEII NUMBEII
.C. COOK - UNIT 1 0 5 0 0 0 0 1 8 8 0 0 0 06 22 90 0 5 0 0 0 THIS REPORT IS SUBMITTED PURSUANT T 0 THE RLQUIREMENTS OF 10 CF R (): (Check One or more ot the torrorrino> (11 OPERATING MODK (9) 1 20.402(tr> 20.405(c) 50.7 3(e) (2) (>v) 73.71(II)
POWER 10.405 ( ~ l(1 I I I) 60.36(c) (Il 50.73(c)(2) (v) 73.71(c)
LEVEL 0 20.405(el(1) (ii) 50.36(c) (2> 50.73( ~ )(2)(v9) OTHER (Soecity tn AOttrect Oererr ~ nd In 7ee f htRC Form 20 405( ~ l(1 l(iiil X 50 73( ~ l(2)R) 50.73(el(21(viii)(A) 366A )
20.406(c) (I 1(iv) 50.73(c>12) lii) 50.73(c)(2>(vi(1) (6) 10.405( ~ Illl(vl 64.73(c I (2)(i i(I 50.73( ~ )(2>(c)
LICENSKK CONTACT FOR THIS LER (12)
- T. P. BEILMAN AREA CODE TELEPHONE NUMBER MAINTENANCE DEPARTMENT SUPERINTENDENT 61 6 65- 59 1 COMPLETE. ONE LINE FOR EACH COMPONE)4T PAILVRE DESCRIBED IH THIS REPORT (13)
CAUSE SYSTEM COMPONENT MANUFAC. MAHUItAC. EPORTABLE TVRER TO HFROS Iy ",~gg@r'Pk>FWmCp~ CAUSE SYSTEM COMPONENT TVRER TO NPRDS Pere Irrpr,";.-:iPN a >pWPP~,i~lyP~
SUPPLEMENTAL REPORT EXPEC'TED (14) MONTH DAY YEAR EXPECTED SUB MISS I 0 N DATE (15)
YES Iit yn, COmnrete fXPfCyfD SVSMISSIOty OATfI NO ABSTRACT ILrmtt to te(k> tercet. r, ~,, eooroeimetely Afteen tinpre toece tyoerrrrtten hnetl (16)
This revision is being submitted to reflect an update on the results of the increased frequency (monthly) calibration checks performed to date.
On March 11, 1988 an equipment trend investigation was being performed on 4KV Bus Loss of Voltage relays and the 4KV Bus Degraded Voltage relays (EIIS/EK-27).
The 'as found'ondition of these relays. during past calibration checks has generally been found to be beyond the Technical Specification (T.S.) allowable values. Each relay was adjusted to within allowable values at the time it was discovered out of specification. All relays were functional and would have performed the ESF function, although at a slightly different voltage than specified in T.S.
An engineering review has determined a plus or minus 3 percent tolerance (as opposed to the current 0.5 percent) to be acceptable for the Loss of Voltage application. The Degraded Voltage application will accept a plus or minus 1.5 percent tolerance and will r'equire installation of more accurate undervoltage relays (Design Change currently underway), A T.S. change request has been submitted. As stated in the original LER, we have increased the calibration frequency from every eighteen months to monthly.
NRC Form 366 (64)91
NRC FORM 366A US. NUCLEAR REGULA'TORY COMMISSION
)669) APPROVEO OMB NO. 31500104 EXPIRESI 4/30/62 LICENSEE EVENT REPORT (LERI ESTIMATED BURDEN PEA RESPONSE TO COMPLY WTH THIS INFORMATION COLLECTION REQUEST; 500 HRS. FORWARD COMMEN'TS REGARDING BURDEN ESTIMATE TO THE RECORDS TEXT CONTINUATION AND REPOATS MANAGEMENT BRANCH (P.530). U.S, NUCLEAR REGULATORY COMMISSION, WASHINGTON. DC 20555, AND TO 1HE PAPERWORK REDUCTION PROJECT 13')500)04), OFFICE OF MANAGEMFNTAND BUDGET,WASHINGTON, DC 20503.
FACILITY NAME 11) DOCKET NUMBER 12)
LER NUMBER LS) PAGE 13)
YEAR .'<."I SEQUENTIAL NUM SR Ill 45VISION NI/M 46 D. C. COOK NUCLEAR PLANT " UNIT 2 TEXT l///44/4 SPPCe JI /PFVPPd. I/>> Pdd/Pe/M//YRC FP//4 366A 3/ l)Tl o s o o o 3 1688 0 3 0 8 02oFO This revision is being submitted to reflect an update on the results of the increased frequency (monthly) calibration checks performed to date.
Conditions Prior to Occurrence Unit 1 and Unit 2 were operating at 90 percent and 80 percent reactor thermal power, respectively, throughout the event. There were no inoperative struc-tures, components, or systems that contributed to this event.
Descri tion of Event On March ll, 1988, an equipment trend investigation was being performed on the 4KV Bus Loss of Voltage relays (EIIS/EK-27) and the 4KV Bus Degraded Voltage relays (EIIS/EK-27). The setpoints for these relays have been found to be outside of the Technical Specification (T.S.) allowable values (T.S. 3.3.2.1 Table 3.3-4, items 8a and 8b). Of 144 individual calibrations on the loss of voltage relays over a seven year period, 68 were found to be outside of the T.S.
tolerances. Of the 66 individual calibrations performed on the degraded voltage relays over a seven year period, 41'ere found to be outside of the T.S.
tolerances. The amount of deviation from the allowable setpoint band was limited and distribution among the relays was random, indicating no particular relay to be defective. A survey of other utilities which use this type of relay revealed that the performance of our relays is consistent with their experience and within manufacturer's specifications. Each relay was readjusted to within allowable values at the time it was discovered out of specification.
The Loss of Voltage relays are installed to sense a loss of offsite or normal auxiliary power to the ESS 4KV buses. Once the loss of voltage has been sensed and after a two-second time delay, these relays in a 2/3 phases logic initiate load shedding and emergency diesel generator starting. The Degraded Bus Voltage relays are installed to sense degraded reserve power feed to the ESS 4KV buses and, on a 2/3 phases logic with a two-minute time delay, trip open the reserve Seed breakers and start the emergency diesel generators. Once the emergency diesel generator has restored bus voltage to normal, safety loads are sequenced on to the safety buses. The Technical Specifications for Units 1 and 2 have existing setpoints of 80 percent (+.5%, -1.0%) for the Loss of Voltage and 90 percent (+1.0%, -.5%) for the Degraded Grid detection. The tolerance on these setpoints are tighter than the relays can obtain, and more importantly, tighter than required for performing their intended function, i.e., sensing loss of normal voltage, initiating load shedding, and diesel starting.
NRC Fon4366A 168S)
V.S, NUCI.EAR REGULATORY COMMISSION APPROV ED OMB 'NO, S(50010<
NRC FORM S66A (689( EXPIRES; ol50(99 WTH THIS EST(MA'TEO BUROFN PER RESPONSE TO COMPLY FORWARD LlCENSEE EVENT REPORT (LER) INFORMATION COLLECTION REQUEST.'00 HRS. THE RECORDS COMMENTS REGARDING BURDEN 'ESTIMATE TO NUCLEAR AND REPORTS MANAGEMENT BRANCH (P 5501. U.S.
TEXT CONTINUATION REGV(.ATORY COMMISSION. WASHINGTON. DC 90555, AND TO OFFICE 1HE PAPERWORK REDUCTION PROJECT IS(500(OOI.
OF MANAGEMENTAND BUDGET, WASHINGTON, DC 90509.
REVISION PAGE (Sl DOCKET NVMBER (EI LER NUMBER L61 FACILITY NAIAE (11 SEQUENTIAL ggS YEAR NUMOER ou NVMSSR COOK NUCLEAR PLANT
" UNIT 2 D. C.
o s o o o 31 88 0 3 0 8 0 3 0F 04 JESA'Jl (IT)
TEXT illmoro Aooco lo (ouuwod. upp oddi doool lVRC Foun Cause of Event Calibration history shows a performance record in line with undervoltage relays used at other plants. We have reviewed the application of undervoltage relays for this function with other utilities and various relay manufacturers.
We have concluded that the undervoltage relays are being properly applied in this mode as a conventional protective relay. This use would not normally involve having an acceptance band. Hany utilities consulted had no Technical Specification required tolerances for this function and others had broader allowance values which more closely reflect the manufacturer's expected performance tolerances.
Anal sis of Event American Electric Power's System voltage studies have been performed and indicate that the worst case voltage on the ESS buses at the Cook Nuclear Plant would be 87.3 percent. We do not expect the ESS bus voltage to drop to a lower voltage than this unless a complete plant blackout condition occurred. Under a blackout condition, the ESS bus voltage would quickly drop well below the 80 percent undervoltage relay setpoint and initiate load shedding and diesel start.
The only function of the 80 percent voltage relays is to seme a total oss 0 f l ESS bus us v voltage. Therefore, the setpoint deviations we'e experienced translate into a different line voltage and time than the Technical Specification calls for, but the time involved for this additional voltage drop is insignificant.
The function of the degraded bus relays are to disconnect the plant from the grid for a sustained degraded condition, i.e., less than 90 percent. voltage for at least.two minutes. They are armed only when the plant is fed from offsite .
power. Plant normal configuration is to be fed from the generator auxiliary transformers except for short periods during startup and shutdown. Therefore, these relays are not normally active during unit operation.
Again, relating to our system studies, we do not believe the shift out of tolerance to be a safety problem for the degraded bus relays. Our studies indicate that the lowest possible offsite voltage to our buses would be 93.3 percent except for the short period during Reactor Coolant Pump (RCP) starting, which is less than one minute. During RCP starting, the bus voltage can dip to 87.3 percent, however, we are protected from an unnecessary trip by the two-minute time delay on this circuit.
N8 C Foun S66A (6$ 91
NRC FORM 366A V.S. NUCLEAR REGULATORY COMMISSION (689 I APPROVED OM8 NO, 3I500106 E XP IR ES: A/30/93 LICENSEE EVENT REPORT (LER) ESTIMATED 8VRDEN PER RESPONSE TO COMPLY WTH THIS INFORMATION COLLECTION REOVEST-, 500 HRS. FORWARD TEXT CONTINUATION COMMENTS REGARDING 8URDEN ESTIMATE TO THE RECORDS AND REPORTS MANAGEMENT BRANCH IP630). U.S. NUCLEAR REGULATORY COMMISSION. WASHINGTON. DC 30555, AND To 1HE PAPERWORK REDUCTION PROJECT I31504104I, OFFICE OF MANAGEMENTAND 8VDGET,WASHINGTON, DC 30503, FACILITY NAME III DOCKET NUMBER I2/
LER NUMBER IEI PAGE IS)
YEAR ': 9 66QUENNAL NUM668
'".n<Y'6' r' NUM 6 n D. C. COOK NUCLEAR PLANT - UNIT 2 0 5 0 0 0 3 1 8 8 0 3 0 8 0 TEXT /llnuup pnpco /F Puquuud, upp pddnenp/ /YRC %%d 366A 9/ I I TI An engineering review has determined a plus or minus 3 percent tolerance (as opposed to the current 0.5 percent) to be acceptable for the Loss of Voltage application. Most of the calibration history data is within 3 percent of the required setpoint. The few exceptions are considered nqrmal random failures.
The Degraded Voltage application will accept a plus or minus 1.5 percent tolerance. This value is suitable for the installation of more accurate undervoltage relays.
Based on the above, it has been concluded that there is no jeopazdy to the health and safety of the public as a result of this event.
Corrective Action The relays were recalibrated to within the allowable values at the time of discovery during the calibration. An engineering review has determined a plus or minus 3 percent tolerance to be acceptable for the Loss of Voltage application and a plus or minus 1.5 percent tolerance for the Degraded Voltage application. A Technical Specification change request has been submitted. In addition, a Design Change regarding the replacement of the currently installed Degraded Voltage relays with more accurate relays is scheduled to be completed at the next refueling outages for both units. As stated in the original LER, we have increased the calibration frequency from every eighteen months to monthly until the trend indicates a different frequency is justified.
Monthly calibration checks have yielded the following results to date:
4KV Loss of Voltage - 528 calibrations 12.3 percent 65 failures 4KV Degraded Voltage - 264 calibrations 15.5 percent 41 failures Failed Com onent Identification None.
Previous Similar Events LER 316/81-015 LER 316/82-108 LER 315/81-017 LER 315/83-069 LER 315/82-051 L'ER 315/83-094 LER 315/82-059 LER 316/82-100 NRC Form 366A I669)