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| I I I I I I I SUPPLEMENTAL REPORT EXPECTED (14) | | I I I I I I I SUPPLEMENTAL REPORT EXPECTED (14) |
| Expected Month l Day i Year Submission lyes (If yes. complete EXPECTED SUBMISSION DATE) X l NO Ll ll ll ABSTRACT (Limit to 1400 spaces, i.e approximately fifteen single-space typewritten lines) (16) | | Expected Month l Day i Year Submission lyes (If yes. complete EXPECTED SUBMISSION DATE) X l NO Ll ll ll ABSTRACT (Limit to 1400 spaces, i.e approximately fifteen single-space typewritten lines) (16) |
| At [[estimated NRC review hours::1800 hours]] on March 3,1989 Reactor Vessel Low Water Level 3 Confinned Automatic Depressurization System (ADS) Pennissive Switch LS-1821-NO38A was found with its setpoint out-of-tolerance in excess of its Reject Limit. The failure was in the conservative direction. This discovery was made during the perfonnance of a routine surveillance while Unit I was in Mode 3, Hot Shutdown. | | At 1800 hours on March 3,1989 Reactor Vessel Low Water Level 3 Confinned Automatic Depressurization System (ADS) Pennissive Switch LS-1821-NO38A was found with its setpoint out-of-tolerance in excess of its Reject Limit. The failure was in the conservative direction. This discovery was made during the perfonnance of a routine surveillance while Unit I was in Mode 3, Hot Shutdown. |
| Because its "As Found" setpoint was still within Technical Specification limits, LS-IB21-NO38A would have properly perfonned its ADS low level confinned function as required in the event of low reactor water level. | | Because its "As Found" setpoint was still within Technical Specification limits, LS-IB21-NO38A would have properly perfonned its ADS low level confinned function as required in the event of low reactor water level. |
| 50R differential pressure instruments which exceed their Reject limits are rejected from further service and replaced.- The switch replacement and calibration were conpleted by [[estimated NRC review hours::2245 hours]] on March 4, 1989. The rejected instrument was disassenbled and inspected to attengt to detennine the root cause of failure. No definite cause of failure could be detennined. Nothing abnonnal was found. The level switch which precipitated this event will be replaced by an analog trip system during the fourth refueling of Unit I, currently scheduled to begin in the Spring of 1991. | | 50R differential pressure instruments which exceed their Reject limits are rejected from further service and replaced.- The switch replacement and calibration were conpleted by 2245 hours on March 4, 1989. The rejected instrument was disassenbled and inspected to attengt to detennine the root cause of failure. No definite cause of failure could be detennined. Nothing abnonnal was found. The level switch which precipitated this event will be replaced by an analog trip system during the fourth refueling of Unit I, currently scheduled to begin in the Spring of 1991. |
| This event is voluntarily reported to the Nuclear Regulatory Comnission in conpliance with the requirements of Inspection Enforcement Bulletin 86-02 (IEB 86-02). | | This event is voluntarily reported to the Nuclear Regulatory Comnission in conpliance with the requirements of Inspection Enforcement Bulletin 86-02 (IEB 86-02). |
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Line 107: |
| : 3) at the time. | | : 3) at the time. |
| The' subject instrissent tripped as expected due to low reactor level during the reactor scram which. | | The' subject instrissent tripped as expected due to low reactor level during the reactor scram which. |
| occurred at [[estimated NRC review hours::2302 hours]] on March 2, 19894 (See LER 373/89-009-00.~) . | | occurred at 2302 hours on March 2, 19894 (See LER 373/89-009-00.~) . |
| The "As Found" setpoint for LS-1821-N038A was 55.2 inches of water colisun ("WC), corresponding to 24.6 ' | | The "As Found" setpoint for LS-1821-N038A was 55.2 inches of water colisun ("WC), corresponding to 24.6 ' |
| ' inches of indicated reactor water. level ("Ihr). The desired setpoint (at atmospheric pressure) of this | | ' inches of indicated reactor water. level ("Ihr). The desired setpoint (at atmospheric pressure) of this |
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| j: | | j: |
| 1 As required by Comonwealth Edison's SOR Long Tenn Action Plan, SOR differential pressure switches which driftbeyondtheirrejectlimitsareconsideredtechnicallyinoperable. Accordingly LS-1821-N038A was | | 1 As required by Comonwealth Edison's SOR Long Tenn Action Plan, SOR differential pressure switches which driftbeyondtheirrejectlimitsareconsideredtechnicallyinoperable. Accordingly LS-1821-N038A was |
| ' declared inoperable at [[estimated NRC review hours::1800 hours]] on March 3, 1989. | | ' declared inoperable at 1800 hours on March 3, 1989. |
| ;j | | ;j |
| ' The'inoperability of this-switch rendered the trip system of ADS Division I inoperable. Technical | | ' The'inoperability of this-switch rendered the trip system of ADS Division I inoperable. Technical |
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| 1 h l The Consnonwealth Edison SOR Long Tenn Action Plan requires that SOR instruments which exceed their' Reject Limits be rejected from further service 44d replaced. Work Request L88000 was written to replace L | | 1 h l The Consnonwealth Edison SOR Long Tenn Action Plan requires that SOR instruments which exceed their' Reject Limits be rejected from further service 44d replaced. Work Request L88000 was written to replace L |
| the rejected instrument with another identical instrument which had been certified for use at LaSalle. | | the rejected instrument with another identical instrument which had been certified for use at LaSalle. |
| L The' switch replacement and calibration were conpleted by [[estimated NRC review hours::2245 hours]] on March 4, 1989 and ADS Division I was declared operable, within the seven days allowed by Technical Specification 3.3.3. | | L The' switch replacement and calibration were conpleted by 2245 hours on March 4, 1989 and ADS Division I was declared operable, within the seven days allowed by Technical Specification 3.3.3. |
| p The rejected instrument was disassenbled and inspected at the station to attengt to detennine the root l: | | p The rejected instrument was disassenbled and inspected at the station to attengt to detennine the root l: |
| .-cause of failure. | | .-cause of failure. |
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Category:LICENSEE EVENT REPORT (SEE ALSO AO
MONTHYEARML20046B1481993-07-30030 July 1993 LER 93-012-00:on 930702,reactor Core Isolation Cooling Sys Declared Inoperable Due to Associated Bus Voltage Dropping Below TS Limits.Sent Operator to Cycle Timer Which Caused Affected Contact to reclose.W/930730 Ltr ML20045D9331993-07-0202 July 1993 LER 93-004-00:on 930604,unexpected CRD Low Charging Water Header Scram Received Followed by Charging Water Header A2/B2 Alarm.Caused by Crud or Foreign Matl Passing Through Suction Filter.Filters Cleaned & reused.W/930702 ML20045D7501993-06-23023 June 1993 LER 93-003-00:on 930524,Div 1 ECCS Initiation Signal Received & LPCS Pump,Lpci Pump 2A & EDG Unit 0 Automatically Started.Caused by Personnel Error.Pumps Secured & Event Documented in Personnel file.W/930623 Ltr ML20044E4161993-05-28028 May 1993 LER 92-009-01:on 920923,spurious Auto Start of CR Ventilation Emergency make-up Train Occurred Due to High Radiation Spike.Radiation Monitor Circuit modified.W/930528 Ltr ML20044E4191993-05-21021 May 1993 LER 93-011-00:on 930423,manual Scram Initiated.Caused by Disconnected Linkage on Valve Positioner on Heater Drain Valve Due to Loose Jam Nut.Tailgate Session Will Be Held W/ Instrument Maint Dept Re Jam nuts.W/930521 Ltr ML20044D5161993-05-15015 May 1993 LER 92-007-01:on 920613,high Radiation Spike Received from CR Ventilation Process Radiation Monitor,Initiating Emergency Makeup Train B.Caused by Normal Variations in Radiation Readings.Spike modified.W/930515 Ltr ML20044D5571993-05-14014 May 1993 LER 93-010-00:on 930414,DG Cooling Water Pump Automatically Tripped on Magnetic Overload.Caused by Inexperienced Trainee in Operation of Control Lever.Lesson Plans & Training Programs for Operators to Be reviewed.W/930514 Ltr ML20044C9801993-05-0707 May 1993 LER 91-010-01:on 910719 & 0805,CR a Ventilation Emergency Makeup Fan auto-started on Spurious Trip of CR Air Intake Process Radiation Monitor.Caused by Normal Variations in Background Radiation.Supply Board replaced.W/930507 Ltr ML20044B6161993-02-25025 February 1993 LER 93-002-00:on 930126,Unit 1 Manual Scram Due to a SRV Being Stuck Open Due to Duct Tape Being Over Actuators Air Valve Manifold Exhaust Port.Maint Procedures That Involve Cleanliness reviewed.W/930225 Ltr ML20024G9771991-05-10010 May 1991 LER 91-005-00:on 910410,determined That Tech Spec Required Surveillance of Suppression Chamber Oxygen Sampling Missed. Caused by Inadequate Review of Tech Spec Change.Drywell & Suppression Chamber Checked for oxygen.W/910510 Ltr ML20044A3851990-06-25025 June 1990 LER 90-008-00:on 900525,Tech Spec Hourly Fire Watch Missed Due to Miscommunications Between Security Personnel & Radiation Protection Personnel.Fire Watch re-established & Memo issued.W/900625 Ltr ML20043F1721990-06-0505 June 1990 LER 90-009-00:on 900510,RWCU Outboard Suction Isolation Valve 2G33-F004 Auto Closed Which Tripped RWCU Pump B. Caused by Procedure Deficiency.Procedure LTS-500-209 Will Be revised.W/900605 Ltr ML20043F1281990-06-0101 June 1990 LER 90-009-00:on 900511,apparent Ruptured Diaphragm Found on Pressure Differential Switch in RCIC Steam Line.Caused by Torn Diaphragm Inside Switch.Replacement Switch Installed, Calibr & Functionally Tested satisfactorily.W/900608 Ltr ML20043B5681990-05-23023 May 1990 LER 89-027-01:on 891113,primary Containment Isolation Sys Group 1 Isolation Occurred During Surveillance Testing. Caused by Burnt Out Window Light Bulbs on Alarm Window. Light Bulbs Replaced & Jumpers installed.W/900523 Ltr ML20043A7721990-05-18018 May 1990 LER 90-007-00:on 900421,reactor Protection Sys Bus a Transfer & Reactor Recirculation Hydraulic Power Unit a Inboard Isolation Valves Closed,Causing Partial Group II isolation.Out-of-svc Procedure revised.W/900518 Ltr ML20043D0591990-05-18018 May 1990 LER 90-008-00:on 900502,ESF Actuation of Control Room B Emergency Ctk Ventilation Makeup Fan Occurred.Caused by Procedure deficiency.LTS-800-205 & Similar Procedures Will Be revised.W/900601 Ltr ML20042H0211990-05-10010 May 1990 LER 90-006-00:on 900412,loop a Primary Containment Chilled Water Sys Inboard Isolation Valves & Reactor Bldg Closed Cooling Water Sys Inboard Isolation Valve Went Closed.Caused by Inadequate Procedure.Procedures revised.W/900510 Ltr ML20042F9001990-05-0404 May 1990 LER 90-005-00:on 900411,experienced Loss of Dc Power to Portion of Div I Primary Containment Isolation Sys Logic Which Resulted in Isolation Signal & Actuation.Caused by Failure to Update Drawings & procedures.W/900504 Ltr ML20042F1941990-04-30030 April 1990 LER 89-025-01:on 891101,sys Auxiliary Transformer Feed to Bus 142Y Tripped Open When Door Containing Undervoltage Relays Closed.Caused by Misalignment of Door.Door Repaired. W/900430 Ltr ML20012D5341990-03-16016 March 1990 LER 90-003-01:on 900201,RCIC Isolation Signal Occurred During Warmup.Caused by Spurious High Steam Flow Signal.Rcic Sys Piping Integrity Verified & Isolation Logic Reset.W/ 900316 Ltr ML20012D5371990-03-16016 March 1990 LER 90-002-01:on 900129,oil in Diesel Generator Governor 1A Found to Be Low & Could Not Be Seen in Sight Glass.Caused by Slow Leak from Compensation Needle Valve Plug.Proper Amount of Oil Added & Operability Test performed.W/900316 Ltr ML20012C4931990-03-15015 March 1990 LER 90-004-00:on 900213,control Room B HVAC Intake Radiation Monitor Lost Power Causing auto-start of Emergency make-up Train B.Caused by Blown Fuses.Fuses Replaced.Logic Revs for Radiation Monitors Will Be installed.W/900315 Ltr ML20012B6501990-03-0909 March 1990 LER 90-002-00:on 900209,Operating Surveillance LOS-TG-W1 Determined to Have Exceeded Required Testing Interval,Per Tech Spec 3/4.7.10.Caused by Personnel Error.Personnel Counseled & Ref Procedures Will Be revised.W/900309 Ltr ML20012B5521990-03-0808 March 1990 LER 90-001-00:on 900206,full Reactor Scram Occurred During Instrument Surveillance Testing.Caused by Actuation of APRM E Trip Circuitry.Shutdown Margin Revised & Caution Card Placed on Control Room Bench board.W/900308 Ltr ML20011F8251990-03-0202 March 1990 LER 90-003-00:on 900201,RCIC Received Div 2 Isolation on RCIC High Steam Line Flow.Caused by Spurious High Steam Flow Signal Generated When Steam/Water Mixture Admitted to RCIC Steam Line.Isolation Logic reset.W/900302 Ltr ML20011F5551990-02-28028 February 1990 LER 90-002-00:on 900129,after Filling Diesel Generator 1A Governor W/Oil,Generator Started & Declared Inoperable. Caused by Slow Leak Coming from Compensation Needle Valve Plug.Oil Added & Plug Washer replaced.W/900228 Ltr ML20006F5951990-02-21021 February 1990 LER 90-001-00:on 900122,RWCU Sys Received Div 1 Leakage Detection Ambient Temp High Isolation Signal,Causing Trips of RWCU Pumps a & C.Caused by Broken Thermocouple Input Lead.Lead Wire Reconnected & Isolation reset.W/900221 Ltr ML20011F4921990-02-16016 February 1990 LER 89-013-01:on 890907,Group I Isolation Received During Performance of Instrument Surveillance LIS-MS-401.Caused by Depressurization of Main Steam Line Low Pressure Switch. Surveillance Revised to Split Into Two parts.W/900216 Ltr ML20006E4501990-02-15015 February 1990 LER 89-010-01:on 890715 & 17,voltage Oscillations Noted on Div II Battery Charger,Resulting in Inoperability of HPCS Sys.Caused by Failure of Charger in High Voltage Shutdown Relay.Charger Energized & Relay replaced.W/900215 Ltr ML20006E4451990-02-14014 February 1990 LER 89-009-01:on 890619,diaphragm Leak Discovered in RCIC Steam Line High Flow Isolation Switch.Caused by 1 & 1/2-inch Tear in Diaphragm.Pressure Differential Switch Replaced & Calibr.Reported Per NRC Bulletin 86-002.W/900214 Ltr ML20006E3981990-02-14014 February 1990 LER 89-008-01:on 890228,reactor Vessel Low Water Level 2 Switch Found W/Setpoint in Excess of Reject Limit.Caused by Setpoint Drift.Channel Placed in Tripped Condition & All Static-O-Ring Pressure Switches to Be replaced.W/900214 Ltr ML20006E3951990-02-14014 February 1990 LER 89-010-01:on 890303,automatic Depressurization Sys Permissive Switch Found W/Setpoint in Excess of Reject Limit.Caused by Setpoint Drift.All Static-O-Ring Reactor Vessel Level Switches Will Be replaced.W/900214 Ltr ML19354D8361990-01-15015 January 1990 LER 89-018-00:on 891216,plant 250-volt Battery & RCIC Sys Declared Inoperable Due to Low Battery Electrolyte Temps. Caused by Failure of Div I Switchgear Heat Removal Sys Damper Actuators.Air Intake Dampers closed.W/900115 Ltr ML20042D3921990-01-0404 January 1990 LER 89-011-01:on 890826,spurious Reactor Protection Sys Actuation Occurred.Definite Cause of Trip Not Determined. Brief Disturbance in Reactor Protection Sys Allowed Some Contactors to Trip.Procedure revised.W/900104 Ltr ML20005E2741989-12-22022 December 1989 LER 89-028-00:on 891204,RHR Shutdown Cooling Suction Header Outboard Isolation Valve Automatically Isolated.Caused by Miscommunication Between Technician & Station Operator.Task Force Developed to Review event.W/891222 Ltr ML19351A6301989-12-15015 December 1989 LER 89-006-01:on 890214,reactor Vessel Low Water Level 3 Switch Setpoint Found Out of Tolerance.Caused by Setpoint Drift.Level Switch to Be Replaced by Analog Trip Sys During First Quarter 1990.W/891215 Ltr ML20011D1341989-12-14014 December 1989 LER 89-017-00:on 891117,flow Switch FS-2E22-N006 Found W/ Setpoint Out of Tolerance Above Reject Limit.Caused by Setpoint Drift.Work Request Written to Replace Flow Switch. W/891214 Ltr ML19351A6751989-12-12012 December 1989 LER 89-027-00:on 891113,primary Containment Isolation Sys Group I Isolation Occurred While Performing Instrument Surveillance.Caused by Loss of Power to Leak Detection Sys Logic.Isolation reset.W/891213 Ltr ML19332F0081989-12-0808 December 1989 LER 89-016-00:on 891109,RWCU Isolation Occurred While Instrument Surveillance on Ventilation Differential Temp Isolation Functional Test in Progress.Caused by Faulty Thermocouple.Thermocouple repaired.W/891208 Ltr ML20005D6621989-12-0606 December 1989 LER 89-026-00:on 891106,inadvertent Primary Containment Isolation Actuation Occurred While Clearing out-of-svc. Caused by Inadequate Logic Setup During Mod Installation. Trip Status & Output Switches repositioned.W/891206 Ltr ML19332F2431989-12-0101 December 1989 LER 89-025-00:on 891101,sys Auxiliary Transformer Feed to Bus 142Y Tripped Open When Equipment Operator Closed Door Containing Relays.Caused by Misalignment of Door.Isolations Reset,Bus Energized & Circuit Logic tested.W/891201 Ltr ML19332E6581989-11-29029 November 1989 LER 89-015-00:on 891030,shift Control Room Engineer Noted That Quarterly Standby Liquid Control Operating Surveillance LOS-SC-Q1 Was Past Critical Date.Caused by Clerical Data Entry Error.Missed Surveillance performed.W/891129 Ltr ML19332D5181989-11-22022 November 1989 LER 89-018-01:on 890515,RCIC Received Div I & Div II Isolation on RCIC High Steam Line Flow.Caused by Spurious High Steam Flow Signal When Steam Added to RCIC Steam Line. Special Test Initiated.Isolation Logic reset.W/891122 Ltr ML19327C2601989-11-17017 November 1989 LER 89-014-00:on 891020,primary Containment Isolation Sys Group 4 Isolation Occurred Causing Isolation Dampers to Close.Caused by Opening of Div 2 125-volt Dc Breaker.Power Supply replaced.W/891117 Ltr ML19325F3411989-11-13013 November 1989 LER 89-024-00:on 891013 & 30,unsealed Openings in Main Control Room Floor & Main Control Room West Wall Discovered. Caused by Wide Gap Between Structural Beam & Cable Tray. Openings Sealed & Fire Watch established.W/891113 Ltr ML19324C1751989-11-0808 November 1989 LER 89-012-01:on 890309,diaphragm Leak Found in Pressure Differential Switch 1E31-N013BB.Caused by Tear Found in Diaphragm.Replacement Switch Installed,Calibr & Functionally Tested satisfactorily.W/891108 Ltr ML20024E9121983-08-26026 August 1983 LER 83-093/03L-0:on 830801,discovered full-in Indication on Core Display for Control Rod 34-47 Inoperable.Caused by Failed Switching Transistor on Data Memory Board 19.Data Memory Board replaced.W/830826 Ltr ML20024B8381983-07-0505 July 1983 LER 83-060/03L-0:on 830606,following Turbine Trip & Scram Due to High Vibration on Main Turbine,Reactor Recirculation Breaker 4B Closed.Cause Undetermined.Auxiliary Contacts cleaned.W/830705 Ltr ML20024B0721983-06-16016 June 1983 Updated LER 83-012/03X-1:on 830210,w/reactor in Cold Shutdown,Setpoints for Switches 1E31-N612A/B Found Above Tech Spec Limits.Cause Unknown.Switches calibr.W/830616 Ltr ML20024A6961983-06-14014 June 1983 LER 83-051/03L-0:on 830516,reactor Protection Sys Trip Channel H2 Limit Switch Failed to Operate Properly.Cause Unknown.Limit Switch readjusted.W/830614 Ltr 1993-07-30
[Table view] Category:RO)
MONTHYEARML20046B1481993-07-30030 July 1993 LER 93-012-00:on 930702,reactor Core Isolation Cooling Sys Declared Inoperable Due to Associated Bus Voltage Dropping Below TS Limits.Sent Operator to Cycle Timer Which Caused Affected Contact to reclose.W/930730 Ltr ML20045D9331993-07-0202 July 1993 LER 93-004-00:on 930604,unexpected CRD Low Charging Water Header Scram Received Followed by Charging Water Header A2/B2 Alarm.Caused by Crud or Foreign Matl Passing Through Suction Filter.Filters Cleaned & reused.W/930702 ML20045D7501993-06-23023 June 1993 LER 93-003-00:on 930524,Div 1 ECCS Initiation Signal Received & LPCS Pump,Lpci Pump 2A & EDG Unit 0 Automatically Started.Caused by Personnel Error.Pumps Secured & Event Documented in Personnel file.W/930623 Ltr ML20044E4161993-05-28028 May 1993 LER 92-009-01:on 920923,spurious Auto Start of CR Ventilation Emergency make-up Train Occurred Due to High Radiation Spike.Radiation Monitor Circuit modified.W/930528 Ltr ML20044E4191993-05-21021 May 1993 LER 93-011-00:on 930423,manual Scram Initiated.Caused by Disconnected Linkage on Valve Positioner on Heater Drain Valve Due to Loose Jam Nut.Tailgate Session Will Be Held W/ Instrument Maint Dept Re Jam nuts.W/930521 Ltr ML20044D5161993-05-15015 May 1993 LER 92-007-01:on 920613,high Radiation Spike Received from CR Ventilation Process Radiation Monitor,Initiating Emergency Makeup Train B.Caused by Normal Variations in Radiation Readings.Spike modified.W/930515 Ltr ML20044D5571993-05-14014 May 1993 LER 93-010-00:on 930414,DG Cooling Water Pump Automatically Tripped on Magnetic Overload.Caused by Inexperienced Trainee in Operation of Control Lever.Lesson Plans & Training Programs for Operators to Be reviewed.W/930514 Ltr ML20044C9801993-05-0707 May 1993 LER 91-010-01:on 910719 & 0805,CR a Ventilation Emergency Makeup Fan auto-started on Spurious Trip of CR Air Intake Process Radiation Monitor.Caused by Normal Variations in Background Radiation.Supply Board replaced.W/930507 Ltr ML20044B6161993-02-25025 February 1993 LER 93-002-00:on 930126,Unit 1 Manual Scram Due to a SRV Being Stuck Open Due to Duct Tape Being Over Actuators Air Valve Manifold Exhaust Port.Maint Procedures That Involve Cleanliness reviewed.W/930225 Ltr ML20024G9771991-05-10010 May 1991 LER 91-005-00:on 910410,determined That Tech Spec Required Surveillance of Suppression Chamber Oxygen Sampling Missed. Caused by Inadequate Review of Tech Spec Change.Drywell & Suppression Chamber Checked for oxygen.W/910510 Ltr ML20044A3851990-06-25025 June 1990 LER 90-008-00:on 900525,Tech Spec Hourly Fire Watch Missed Due to Miscommunications Between Security Personnel & Radiation Protection Personnel.Fire Watch re-established & Memo issued.W/900625 Ltr ML20043F1721990-06-0505 June 1990 LER 90-009-00:on 900510,RWCU Outboard Suction Isolation Valve 2G33-F004 Auto Closed Which Tripped RWCU Pump B. Caused by Procedure Deficiency.Procedure LTS-500-209 Will Be revised.W/900605 Ltr ML20043F1281990-06-0101 June 1990 LER 90-009-00:on 900511,apparent Ruptured Diaphragm Found on Pressure Differential Switch in RCIC Steam Line.Caused by Torn Diaphragm Inside Switch.Replacement Switch Installed, Calibr & Functionally Tested satisfactorily.W/900608 Ltr ML20043B5681990-05-23023 May 1990 LER 89-027-01:on 891113,primary Containment Isolation Sys Group 1 Isolation Occurred During Surveillance Testing. Caused by Burnt Out Window Light Bulbs on Alarm Window. Light Bulbs Replaced & Jumpers installed.W/900523 Ltr ML20043A7721990-05-18018 May 1990 LER 90-007-00:on 900421,reactor Protection Sys Bus a Transfer & Reactor Recirculation Hydraulic Power Unit a Inboard Isolation Valves Closed,Causing Partial Group II isolation.Out-of-svc Procedure revised.W/900518 Ltr ML20043D0591990-05-18018 May 1990 LER 90-008-00:on 900502,ESF Actuation of Control Room B Emergency Ctk Ventilation Makeup Fan Occurred.Caused by Procedure deficiency.LTS-800-205 & Similar Procedures Will Be revised.W/900601 Ltr ML20042H0211990-05-10010 May 1990 LER 90-006-00:on 900412,loop a Primary Containment Chilled Water Sys Inboard Isolation Valves & Reactor Bldg Closed Cooling Water Sys Inboard Isolation Valve Went Closed.Caused by Inadequate Procedure.Procedures revised.W/900510 Ltr ML20042F9001990-05-0404 May 1990 LER 90-005-00:on 900411,experienced Loss of Dc Power to Portion of Div I Primary Containment Isolation Sys Logic Which Resulted in Isolation Signal & Actuation.Caused by Failure to Update Drawings & procedures.W/900504 Ltr ML20042F1941990-04-30030 April 1990 LER 89-025-01:on 891101,sys Auxiliary Transformer Feed to Bus 142Y Tripped Open When Door Containing Undervoltage Relays Closed.Caused by Misalignment of Door.Door Repaired. W/900430 Ltr ML20012D5341990-03-16016 March 1990 LER 90-003-01:on 900201,RCIC Isolation Signal Occurred During Warmup.Caused by Spurious High Steam Flow Signal.Rcic Sys Piping Integrity Verified & Isolation Logic Reset.W/ 900316 Ltr ML20012D5371990-03-16016 March 1990 LER 90-002-01:on 900129,oil in Diesel Generator Governor 1A Found to Be Low & Could Not Be Seen in Sight Glass.Caused by Slow Leak from Compensation Needle Valve Plug.Proper Amount of Oil Added & Operability Test performed.W/900316 Ltr ML20012C4931990-03-15015 March 1990 LER 90-004-00:on 900213,control Room B HVAC Intake Radiation Monitor Lost Power Causing auto-start of Emergency make-up Train B.Caused by Blown Fuses.Fuses Replaced.Logic Revs for Radiation Monitors Will Be installed.W/900315 Ltr ML20012B6501990-03-0909 March 1990 LER 90-002-00:on 900209,Operating Surveillance LOS-TG-W1 Determined to Have Exceeded Required Testing Interval,Per Tech Spec 3/4.7.10.Caused by Personnel Error.Personnel Counseled & Ref Procedures Will Be revised.W/900309 Ltr ML20012B5521990-03-0808 March 1990 LER 90-001-00:on 900206,full Reactor Scram Occurred During Instrument Surveillance Testing.Caused by Actuation of APRM E Trip Circuitry.Shutdown Margin Revised & Caution Card Placed on Control Room Bench board.W/900308 Ltr ML20011F8251990-03-0202 March 1990 LER 90-003-00:on 900201,RCIC Received Div 2 Isolation on RCIC High Steam Line Flow.Caused by Spurious High Steam Flow Signal Generated When Steam/Water Mixture Admitted to RCIC Steam Line.Isolation Logic reset.W/900302 Ltr ML20011F5551990-02-28028 February 1990 LER 90-002-00:on 900129,after Filling Diesel Generator 1A Governor W/Oil,Generator Started & Declared Inoperable. Caused by Slow Leak Coming from Compensation Needle Valve Plug.Oil Added & Plug Washer replaced.W/900228 Ltr ML20006F5951990-02-21021 February 1990 LER 90-001-00:on 900122,RWCU Sys Received Div 1 Leakage Detection Ambient Temp High Isolation Signal,Causing Trips of RWCU Pumps a & C.Caused by Broken Thermocouple Input Lead.Lead Wire Reconnected & Isolation reset.W/900221 Ltr ML20011F4921990-02-16016 February 1990 LER 89-013-01:on 890907,Group I Isolation Received During Performance of Instrument Surveillance LIS-MS-401.Caused by Depressurization of Main Steam Line Low Pressure Switch. Surveillance Revised to Split Into Two parts.W/900216 Ltr ML20006E4501990-02-15015 February 1990 LER 89-010-01:on 890715 & 17,voltage Oscillations Noted on Div II Battery Charger,Resulting in Inoperability of HPCS Sys.Caused by Failure of Charger in High Voltage Shutdown Relay.Charger Energized & Relay replaced.W/900215 Ltr ML20006E4451990-02-14014 February 1990 LER 89-009-01:on 890619,diaphragm Leak Discovered in RCIC Steam Line High Flow Isolation Switch.Caused by 1 & 1/2-inch Tear in Diaphragm.Pressure Differential Switch Replaced & Calibr.Reported Per NRC Bulletin 86-002.W/900214 Ltr ML20006E3981990-02-14014 February 1990 LER 89-008-01:on 890228,reactor Vessel Low Water Level 2 Switch Found W/Setpoint in Excess of Reject Limit.Caused by Setpoint Drift.Channel Placed in Tripped Condition & All Static-O-Ring Pressure Switches to Be replaced.W/900214 Ltr ML20006E3951990-02-14014 February 1990 LER 89-010-01:on 890303,automatic Depressurization Sys Permissive Switch Found W/Setpoint in Excess of Reject Limit.Caused by Setpoint Drift.All Static-O-Ring Reactor Vessel Level Switches Will Be replaced.W/900214 Ltr ML19354D8361990-01-15015 January 1990 LER 89-018-00:on 891216,plant 250-volt Battery & RCIC Sys Declared Inoperable Due to Low Battery Electrolyte Temps. Caused by Failure of Div I Switchgear Heat Removal Sys Damper Actuators.Air Intake Dampers closed.W/900115 Ltr ML20042D3921990-01-0404 January 1990 LER 89-011-01:on 890826,spurious Reactor Protection Sys Actuation Occurred.Definite Cause of Trip Not Determined. Brief Disturbance in Reactor Protection Sys Allowed Some Contactors to Trip.Procedure revised.W/900104 Ltr ML20005E2741989-12-22022 December 1989 LER 89-028-00:on 891204,RHR Shutdown Cooling Suction Header Outboard Isolation Valve Automatically Isolated.Caused by Miscommunication Between Technician & Station Operator.Task Force Developed to Review event.W/891222 Ltr ML19351A6301989-12-15015 December 1989 LER 89-006-01:on 890214,reactor Vessel Low Water Level 3 Switch Setpoint Found Out of Tolerance.Caused by Setpoint Drift.Level Switch to Be Replaced by Analog Trip Sys During First Quarter 1990.W/891215 Ltr ML20011D1341989-12-14014 December 1989 LER 89-017-00:on 891117,flow Switch FS-2E22-N006 Found W/ Setpoint Out of Tolerance Above Reject Limit.Caused by Setpoint Drift.Work Request Written to Replace Flow Switch. W/891214 Ltr ML19351A6751989-12-12012 December 1989 LER 89-027-00:on 891113,primary Containment Isolation Sys Group I Isolation Occurred While Performing Instrument Surveillance.Caused by Loss of Power to Leak Detection Sys Logic.Isolation reset.W/891213 Ltr ML19332F0081989-12-0808 December 1989 LER 89-016-00:on 891109,RWCU Isolation Occurred While Instrument Surveillance on Ventilation Differential Temp Isolation Functional Test in Progress.Caused by Faulty Thermocouple.Thermocouple repaired.W/891208 Ltr ML20005D6621989-12-0606 December 1989 LER 89-026-00:on 891106,inadvertent Primary Containment Isolation Actuation Occurred While Clearing out-of-svc. Caused by Inadequate Logic Setup During Mod Installation. Trip Status & Output Switches repositioned.W/891206 Ltr ML19332F2431989-12-0101 December 1989 LER 89-025-00:on 891101,sys Auxiliary Transformer Feed to Bus 142Y Tripped Open When Equipment Operator Closed Door Containing Relays.Caused by Misalignment of Door.Isolations Reset,Bus Energized & Circuit Logic tested.W/891201 Ltr ML19332E6581989-11-29029 November 1989 LER 89-015-00:on 891030,shift Control Room Engineer Noted That Quarterly Standby Liquid Control Operating Surveillance LOS-SC-Q1 Was Past Critical Date.Caused by Clerical Data Entry Error.Missed Surveillance performed.W/891129 Ltr ML19332D5181989-11-22022 November 1989 LER 89-018-01:on 890515,RCIC Received Div I & Div II Isolation on RCIC High Steam Line Flow.Caused by Spurious High Steam Flow Signal When Steam Added to RCIC Steam Line. Special Test Initiated.Isolation Logic reset.W/891122 Ltr ML19327C2601989-11-17017 November 1989 LER 89-014-00:on 891020,primary Containment Isolation Sys Group 4 Isolation Occurred Causing Isolation Dampers to Close.Caused by Opening of Div 2 125-volt Dc Breaker.Power Supply replaced.W/891117 Ltr ML19325F3411989-11-13013 November 1989 LER 89-024-00:on 891013 & 30,unsealed Openings in Main Control Room Floor & Main Control Room West Wall Discovered. Caused by Wide Gap Between Structural Beam & Cable Tray. Openings Sealed & Fire Watch established.W/891113 Ltr ML19324C1751989-11-0808 November 1989 LER 89-012-01:on 890309,diaphragm Leak Found in Pressure Differential Switch 1E31-N013BB.Caused by Tear Found in Diaphragm.Replacement Switch Installed,Calibr & Functionally Tested satisfactorily.W/891108 Ltr ML20024E9121983-08-26026 August 1983 LER 83-093/03L-0:on 830801,discovered full-in Indication on Core Display for Control Rod 34-47 Inoperable.Caused by Failed Switching Transistor on Data Memory Board 19.Data Memory Board replaced.W/830826 Ltr ML20024B8381983-07-0505 July 1983 LER 83-060/03L-0:on 830606,following Turbine Trip & Scram Due to High Vibration on Main Turbine,Reactor Recirculation Breaker 4B Closed.Cause Undetermined.Auxiliary Contacts cleaned.W/830705 Ltr ML20024B0721983-06-16016 June 1983 Updated LER 83-012/03X-1:on 830210,w/reactor in Cold Shutdown,Setpoints for Switches 1E31-N612A/B Found Above Tech Spec Limits.Cause Unknown.Switches calibr.W/830616 Ltr ML20024A6961983-06-14014 June 1983 LER 83-051/03L-0:on 830516,reactor Protection Sys Trip Channel H2 Limit Switch Failed to Operate Properly.Cause Unknown.Limit Switch readjusted.W/830614 Ltr 1993-07-30
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML20217C9121999-10-12012 October 1999 SER Input Authorizing Licensee Proposed Request to Modify Definition of Core Alteration in Section 1.0 of TS & Update Sections 3/4.1,3.4.3 & 3/4.9 to Reflect Proposed Definition Change ML20217F9091999-09-30030 September 1999 Monthly Operating Repts for Sept 1999 for LaSalle County Stations,Units 1 & 2.With ML20217A1691999-09-22022 September 1999 Part 21 Rept Re Engine Sys,Inc Controllers,Manufactured Between Dec 1997 & May 1999,that May Have Questionable Soldering Workmanship.Caused by Inadequate Personnel Training.Sent Rept to All Nuclear Customers ML20212C4501999-08-31031 August 1999 Monthly Operating Repts for Aug 1999 for LaSalle County Station,Units 1 & 2.With ML20210R0671999-07-31031 July 1999 Monthly Operating Repts for July 1999 for LaSalle County Station,Units 1 & 2.With ML20210C1681999-07-0909 July 1999 Seventh Refueling Outage ASME Section XI Summary Rept ML20209H1501999-06-30030 June 1999 Monthly Operating Repts for June 1999 for LaSalle County Station,Units 1 & 2.With ML20195J7871999-05-31031 May 1999 Monthly Operating Repts for May 1999 for LaSalle County Station,Units 1 & 2.With ML20209E1431999-05-31031 May 1999 Cycle 8 COLR, for May 1999 ML20195B2591999-05-19019 May 1999 Rev 66a to CE-1-A,consisting of Proposed Changes to QAP for Dnps,Qcs,Znps,Lcs,Byron & Braidwood Stations ML20206N2071999-04-30030 April 1999 Monthly Operating Repts for Apr 1999 for LaSalle County Station,Units 1 & 2.With ML20205L8421999-03-31031 March 1999 Rev 2 to EMF-96-125, LaSalle Unit 2 Cycle 8 Reload Analysis ML20205L8301999-03-31031 March 1999 Administrative Technical Requirements App B (Amend 26) LaSalle Unit 2 Cycle 8 COLR & Reload Transient Analysis Results, for Mar 1999 ML20205R2721999-03-31031 March 1999 Monthly Operating Repts for Mar 1999 for LaSalle County Station,Units 1 & 2.With ML20205L8391999-03-22022 March 1999 Rev 2 to 960103, Neutronics Licensing Rept for LaSalle Unit 2,Cycle 8 ML20204C8141999-02-28028 February 1999 Monthly Operating Repts for Feb 1999 for LaSalle County Station,Units 1 & 2.With ML20199E4601998-12-31031 December 1998 Monthly Operating Repts for Dec 1998 for LaSalle County Station,Units 1 & 2.With ML20207C7371998-12-31031 December 1998 Annual Rept for LaSalle County Station for Jan 1998 Through Dec 1998 ML20205M7061998-12-31031 December 1998 Unicom Corp 1998 Summary Annual Rept. with ML20198B3801998-12-14014 December 1998 SER Accepting one-time Request for Relief from Certain Provisions of Section XI of ASME Boiler & Pressure Vessel Code,Per 10CFR50.55a for Certain Plant Safety/Relief Valves ML20206N2261998-12-0909 December 1998 LER 98-S03-00:on 981116,protected Area Was Entered Without Current Authorization for Unescorted Access Due to Programmatic Deficiency Error.Changed Badge Control Process ML20197K0981998-11-30030 November 1998 Monthly Operating Repts for Nov 1998 for LaSalle County Station,Unts 1 & 2.With ML20196B1441998-11-23023 November 1998 Safety Evaluation Accepting Licensee Response to GL 95-07, Pressure Locking & Thermal Bindings of Safety-Related Power-Operated Gate Valves ML20196A4191998-11-19019 November 1998 Safety Evaluation Accepting QA TR CE-1-A,Rev 66 Re Changes in Independent & Onsite Review Organization by Creating NSRB ML20195D3191998-10-31031 October 1998 Monthly Operating Repts for Oct 1998 for LaSalle County Station.With ML20154H6781998-09-30030 September 1998 Monthly Operating Repts for Sept 1998 for LaSalle County Nuclear Power Station,Units 1 & 2 ML20153D0191998-09-18018 September 1998 Part 21 Rept Re Defect in Gap Conductance Analyses for co- Resident BWR Fuel.Initially Reported on 980917.Corrective Analyses Performed Demonstrating That Current Operating Limits Bounding from BOC to Cycle Exposure of 8 Gwd/Mtu ML20153C7621998-09-18018 September 1998 Safety Evaluation Acceping NRC Bulletin 95-002, Unexpected Clogging of RHR Pump Strainer While Operating in Suppression Pool Cooling Mode ML20153C6771998-09-17017 September 1998 Part 21 Rept Re Defect Relative to MCPR Operating Limits as Impacted by Gap Conductance of co-resident BWR Fuel at Facilities.Operating Limit for LaSalle Unit 2 & Quad Cities Unit 2 Will Be Revised as Listed ML20151W0241998-08-31031 August 1998 Monthly Operating Repts for Aug 1998 for LaSalle County Station.With ML20237E2921998-08-21021 August 1998 Special Rept:On 980811,channel 5 of Lpms Became Inoperable. Caused by Channel Failed pre-amplifier Located Inside Primary Containment at Inboard Side of Electrical Penetration E-19.Initiated Repairs of Channel ML20237E2331998-08-21021 August 1998 Revised Pages of Section 20 of Rev 66 to CE-1-A, QA Topical Rept ML20237B4861998-07-31031 July 1998 Monthly Operating Repts for July 1998 for LaSalle County Nuclear Power Station Units 1 & 2 ML20236V7701998-07-31031 July 1998 Revised LaSalle Unit 1 Cycle 8 COLR & Reload Transient Analysis Results ML20236P8231998-07-14014 July 1998 Special Rept:From 980614-17,various Fire Rated Assemblies Were Inoperable for Period Greater than Seven Days.Caused by Test Equipment Being Routed Through Fire Doors.Established Fire Watches & on 980619 Assemblies Were Declared Operable ML20236N6751998-07-0909 July 1998 Part 21 & Deficiency Rept Re Notification of Potential Safety Hazard from Breakage of Cast Iron Suction Heads in Apkd Type Pumps.Caused by Migration of Suction Head Journal Sleeve Along Lower End of Pump Shaft.Will Inspect Pumps ML20236L8041998-07-0606 July 1998 Safety Evaluation Granting Licensee 980304 Request for Second 10-yr Interval Pump & Valve IST Program Plan,Rev 2, Including Changes to 2 ASME Boiler & Pressure Vessel Code Relief Requests Previously Submitted in Rev 1 ML20236P3611998-06-30030 June 1998 Monthly Operating Repts for June 1998 for LaSalle County Nuclear Power Station,Units 1 & 2 ML20249C4891998-06-22022 June 1998 Special Rept:On 980522,Fire Detection Zone 1-31 Was Noted out-of-service for More than 14 Days.Detection Sys Was Taken out-of-service on 980508 to Prevent False Alarms During Hot Work Activities.Sys Was Returned to Operable Status 980528 ML20248M3101998-05-31031 May 1998 Monthly Operating Repts for May 1998 for LaSalle County Nuclear Power Station,Units 1 & 2 ML20236V7771998-05-31031 May 1998 Rev 1 to 24A5180, Supplemental Reload Licensing Rept for LaSalle County Station Unit 1 Reload 7 Cycle 8 ML20217Q7041998-05-0404 May 1998 Safety Evaluation Accepting Util Request to Leave Leak Chase Channels Plugged During Performance of Containment ILRT ML20247M4491998-04-30030 April 1998 Monthly Operating Repts for Apr 1998 for LaSalle County Station ML20216F4941998-03-31031 March 1998 Monthly Operating Repts for Mar 1998 for LaSalle County Station,Units 1 & 2 ML20217N6581998-03-30030 March 1998 Special Rept on Fire Detection,Deluge Sys & Fire Rated Assemblies During Period of 980303-25.Established Fire Watches Until Affected Equipment Is Returned to Operable Status ML20216D9511998-02-28028 February 1998 Monthly Operating Repts for Feb 1998 for LaSalle County Station,Units 1 & 2 ML20247M4631998-02-28028 February 1998 Rev Monthly Operating Rept for Feb 1998 for LaSalle County Station ML20203D7241998-02-20020 February 1998 Special Rept:On 980118,Fire Detection Zones 1-18 & 2-18 Taken out-of-svc to Prevent False Alarms During Hot Work Activities on Auxiliary Electric Equipment Room Ventilation Sys.Fire Watches Will Remain in Place ML20202G9851998-01-31031 January 1998 Monthly Operating Repts for Jan 1998 for LaSalle County Station,Units 1 & 2 ML20199K1651998-01-23023 January 1998 Rev 65h to Topical Rept CE-1-A, Comm Ed QA Tr 1999-09-30
[Table view] |
Text
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, .: _l Y 1' Commow oalth Edison
- - LtSalle County Nuctrar Station ,
- .4 . Rurat Route #1, Box 220
l~ 3- Marseilles, Illinois 61341 N O : Telephone 815/357 6761
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February 14, 1990 l
Director of. Nuclear Reactor Regulation U.S. Nuclear Regulatory Coasaission Mail Station F1-137 j Washington, D.C. 20555
Dear Sir:
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Licensee Event Report #89-010-01, Docket #050-373 is being 9 sutaitted to your office to supercede previously submitted Licensee Event Report 89-010-00 which was reported pursuant to NRC 1.E. Bulletin 86-02, " Static-O-Ring Differential Pressure Switch."
NO G. J. Diedert h hlstationManager LaSalle County Station GJD/NWJ/kg ~l Enclosure I
.xc: Nuclear Licensing Administrator NRC Resident Inspector NRC Region III Administrator l
INPO - Records Center l l
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I ll pff223OO49 S ADOCK O 9$0 hob 73 PDC . ') ,'f'!
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p LICENSEE EVENT REPORT (LER) Fonn Rev 2.0 Docket Nunber (2) Pace (3)
Facility Name (1)
L W 11e County Station Unit 1 01 51 01 01 01 31 11 3 1lofl0l5 Title (4) "
Setool'nt Drift of Low Level Confinned Automatic Depressurization System Pennissive Switch LER N m r (6) Report Date (7) Other Facilities involved (8)
Event Date (5) Facility Names Docket Wweer(s)
Day Year Year / Sequential Revision Month Day Year Month
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01 51 01 01 01 1 I L
01 3 01 3 81 9 81 9
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0l 1 0l2 11 4 91 0 0151010101 l l l TH15 REPORT IS SUBMI1TED PUR$UANT TO THE REQUIREMENTS OF 10CFR (Check one or more of the followine) (11)
MODE W 3 20.402(b) 20.405(c) _ 50.73(a)(2)(iv) _
73.71(b) 20.405(a)(1)(1) 50.36(c)(1) _ 50.73(a)(2)(v) _
73.7t(c) .;
- i. POWER _ _
50.36(c)(2) 50.73(a)(2)(vil) ]L Other (Specify-L LEVEL 20.405(a)(1)(ll) _ _
50.73(a)(2)(vill)(A) in Abstract (10) 0l0l0 _ 20.405(a)(1)(lii) _
50.73(a)(2)(l) _
50.73(a)(2)(vill)(B) below and in
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'/'j'j/ 'j'j'j'j'j/'/'/// _ 20.405(a)(1)(v) _ _
LICENSEE CONTACT FOR THIS LER (12)
TELEPHONE NUISER Name AREA CODE Ned Jacklin. Technical Staff Enoineer, extension 2397 8 l 1 15 315171-l6171611 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)
CAUSE ' SYSTEM COMPONENT MANUFAC- REPORTABLE CAUSE SYSTEM COMPONENT MANUFAC- REPORTABLE TURER' TO WPROS TURER TO WPRDS=
X 5I B l l Li S SI31812 Y I l i I I l l i I I I l l l .
I I I I I I I SUPPLEMENTAL REPORT EXPECTED (14)
Expected Month l Day i Year Submission lyes (If yes. complete EXPECTED SUBMISSION DATE) X l NO Ll ll ll ABSTRACT (Limit to 1400 spaces, i.e approximately fifteen single-space typewritten lines) (16)
At 1800 hours0.0208 days <br />0.5 hours <br />0.00298 weeks <br />6.849e-4 months <br /> on March 3,1989 Reactor Vessel Low Water Level 3 Confinned Automatic Depressurization System (ADS) Pennissive Switch LS-1821-NO38A was found with its setpoint out-of-tolerance in excess of its Reject Limit. The failure was in the conservative direction. This discovery was made during the perfonnance of a routine surveillance while Unit I was in Mode 3, Hot Shutdown.
Because its "As Found" setpoint was still within Technical Specification limits, LS-IB21-NO38A would have properly perfonned its ADS low level confinned function as required in the event of low reactor water level.
50R differential pressure instruments which exceed their Reject limits are rejected from further service and replaced.- The switch replacement and calibration were conpleted by 2245 hours0.026 days <br />0.624 hours <br />0.00371 weeks <br />8.542225e-4 months <br /> on March 4, 1989. The rejected instrument was disassenbled and inspected to attengt to detennine the root cause of failure. No definite cause of failure could be detennined. Nothing abnonnal was found. The level switch which precipitated this event will be replaced by an analog trip system during the fourth refueling of Unit I, currently scheduled to begin in the Spring of 1991.
This event is voluntarily reported to the Nuclear Regulatory Comnission in conpliance with the requirements of Inspection Enforcement Bulletin 86-02 (IEB 86-02).
- - .~ . _. _
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Fom Rev 21 j iFACILITY NAlt (1).
Lire *KEE EVENT REPORT (LER) TEXT CONTINUATION DOCKET NUPSER (2). LER C R (6) Pace (3)- j e . Year g/// Sequ;ntial // Revision i thaber~ /j/j/
J /// / Number _ -$
lie County Station' unit 1.*
O l'5 l'0 1 0 l'0 l'31 il 3 819
- 0 l l'l 0 - 0 l- 1 01 2 0F 01 5 f '
' , TEXT . . Energy Industry identification System (Ells) codes are identified in the text as [XX]-;
n i j
PLANT [ AND SYSTEM IDEWilflCATION i
General Electric - Bolling Water Reactor i
'l n
- Energy Industry identification System (Ells) codes are identified in the text as (XX].
l A. CONDITION PRIOR TO EVENT Unit (s): l, Event Date: 3/3/89 Event Time: 1000 Hours- ]
3 Mode (s) Name: Hot Shutdown . Power Level (s): '05 Reactor Mode (s):
L
, 8. DESCRIPTION OF EVENT Reactor Vessel (NB)'[AD) Low Water Level 3 Confimed Automatic Depressurization System (ADS) (58]
' Pemissive Switch LS-1821-NO38A was found with its setpoint out-of-tolerance in excess of its Reject.
Limit in the conservative direction.. This discovery,was made at 1800, hours on March 3, 1989,.during the perfomance of 'LaSalle Ins'trument Surveillance LIS-N8-106, " Unit 1 Reactor Vessel Low Water Level .
Confimed Automatic Depressurization System Pemissive Calibration." Unit I was in Hot Shutdown (Pode
- 3) at the time.
The' subject instrissent tripped as expected due to low reactor level during the reactor scram which.
occurred at 2302 hours0.0266 days <br />0.639 hours <br />0.00381 weeks <br />8.75911e-4 months <br /> on March 2, 19894 (See LER 373/89-009-00.~) .
The "As Found" setpoint for LS-1821-N038A was 55.2 inches of water colisun ("WC), corresponding to 24.6 '
' inches of indicated reactor water. level ("Ihr). The desired setpoint (at atmospheric pressure) of this
~
switch is 19.40 "ItiL (58.9 "WC) with a tolerance of +/- 0.71 " Inn. (>/- 0.50 "WC), Action Limits of +/-
3.% ."Init (+/- 2.80 "WC), and Reject- Limits of +/- 4.10 "Indt (+/- 2.90 "WC). The upper Reject Limits is ' i
' 23.5 "It#L, so the "As Found" setpoint exceeded the Reject Limit by 1.1 "Infl. :The Technical' Specification Limiting Condition for operation is >/= 11.00 "IniL (</= 64.84 "WC) with a Nominal' Trip Setpoint of 12.50 "InlL (63.78 "WC). The infonnation in this paragraph is graphically displayed in
-i Figure 1. l LS-1821-NO38A is an SOR differential pressure switch of a type.which displays a shift in setpoint when
> placed at an elevated static pressure. This switch functions to confirm a low level in the reactor vessel and allow operation of Olvision 1 of ADS. This function was not inpaired by the out-of-tolerance ,
Jsetpoint.,
- This event is voluntarily reported to the Nuclear Regulatory Comnission in compliance with the
. requirements of Inspection Enforcement Bulletin 86-02 (IE8 86-02). Personnel error did not influence
{
fe the cause or severity of this event. The actions taken by plant personnel in response to this event were timely and appropriate.
a
LICE *ME EVENT REPORT (LER) TEXT CONTINUATION Fom Rev 2.0 DOCKET NUSER (2) LER NHSER (6) Pee (3) ';
FACILITY NAME (1)
Year / . Sequential //j/ Revision k-J' - g//j/
/ Neter fM/ Nueer_ [
b 0 l'1 1 0 0 l-- 01 3 0F 01 5 h.
leMlle County Station Unit l' 0 l 5 1 0 1 0 1 0 l 31 71 3 8l9 - - 1
,> TEXT' Energy Industry identification System (Ells) codes are identified in the text as (XXJ C. APPARENT CAUSE OF EVENT This event was doparently caused by setpoint drift. After an initial actuation of a SOR dP switch, subsequent actuations (within a short time after the initial trip) tend to occur at a low differential pressure (conservative direction). This may also have contributed to the calibratton'setpoint being-foundintheconservativedirectionoutsidetherejectband.
~F
-The instrument wa: disasseeled and inspected at the station.to attenyt to detennine the cause of-fallure. No damage or other abnormalities were noted.
D. SAFETY ANALYSIS OF EVENT
? This event did not degrade plant safety. ,
LS-1821-#038A would have functioned as required in the event of low water level in the reactor vessel.
'Its "As Found" setpoint was within Technical Specification Ilmits. Also, since a vessel water level of L -129 " Inn. must occur before ADS automatically initiates, it is certain that this switch would have tripped by the time reactor water level became low enough.to generate an initiation signal. i h
- 1. * )
l l E. CORRECTIVE ACTIONS I 3
j:
1 As required by Comonwealth Edison's SOR Long Tenn Action Plan, SOR differential pressure switches which driftbeyondtheirrejectlimitsareconsideredtechnicallyinoperable. Accordingly LS-1821-N038A was
' declared inoperable at 1800 hours0.0208 days <br />0.5 hours <br />0.00298 weeks <br />6.849e-4 months <br /> on March 3, 1989.
- j
' The'inoperability of this-switch rendered the trip system of ADS Division I inoperable. Technical
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l' Action i -Specification 3.3.3 requires the ADS trip systems to be operable in Plant Conditions 1, 2 and 3.
' Statement C of this specification requires that an inoperable ADS trip system must be restored to l
operability within seven days, provided the other ADS trip systems, High Pressure Core Spray (HPCS) l- )
l [9G), and Reactor Core Isolation Cooling (RCIC) [8N] remain operable.
1 h l The Consnonwealth Edison SOR Long Tenn Action Plan requires that SOR instruments which exceed their' Reject Limits be rejected from further service 44d replaced. Work Request L88000 was written to replace L
the rejected instrument with another identical instrument which had been certified for use at LaSalle.
L The' switch replacement and calibration were conpleted by 2245 hours0.026 days <br />0.624 hours <br />0.00371 weeks <br />8.542225e-4 months <br /> on March 4, 1989 and ADS Division I was declared operable, within the seven days allowed by Technical Specification 3.3.3.
p The rejected instrument was disassenbled and inspected at the station to attengt to detennine the root l:
.-cause of failure.
l l-i l
l
- n LICENSEE EVENT REPORT (LER) TEXT CONTINUATION Form Rev 2.0 FACILITY NAME (1) DOCKET NU SER (2) LER NU SER (6) Pace (3)
Year- /// Sequential /jjj/
/ Revision j/jj
// Nueer /// Nweer__
LaSalle County Station Unit I- 0'l 5 1 0 l'0 l 0 1 31 71 3 8l9 - 0l110 - 0l 1 01 4 0F 01 5 l-TEXT Energy Industry identification System (Ell 5) codes are identified in the text as [XX)
'E. CORRECTIVE ACTIONS (Continued)
Modifications are planned to remove all SOR reactor vessel level switches at LaSalle and replace them with analog trip units. The analog trip units were chosen partly because of their setpoint stability.
They are expected to inprove the perfonnance of the Reactor Vessel Wter Level Sensing System. The level switch which precipitated this event will be replaced under modification M01 1-87-097 during the fourth refueling of Unit 1, currently scheduled to begin in the Spring of 1991. Action item Record AIR 373-123-87-00003 is tracking the completion of this modification. ,
F. PREVIOUS EVENTS l: LER Wunt>er Title t
374/96-007-00 Excessive Static-0-Ring Pressure Switch Drift 374/96-011-01 Failure of 12.5" DP Level Switch to Respond to Low Level ,
374/96-019-01 Reactor vessel Low Level Confimed ADS Pemissive Switch Out of Tolerance Due to Setpoint Drift 373/87-013-01 Automatic Depressurization System Low Level Confimed Switch Setpoint Found Out. of j.
Tolerance Due'to Setpoint Drift 374/87-011-01 Residual Heat Removal Peip Minimun Flow Bypass Differential Pressure Switch found L
l- Out of Tolerance Due to Setpoint Drift 373/88-028-01 Setpoint Drift of Reactor Vessel Low W ter Level Switch 373/88-029-01 Setpoint Drift of Low Level Confinned Automatic Depressurization System Permissive Switch 374/88-005-01 High Pressure Core Spray Minimun Flow Bypass Flow Switch Out of Tolerance Due to L Setpoint Drift 374/88-013-01 Low Pressure Core Spray Mininen Flow Bypass Differential Switch Found Above RejectionLimit 374/88-015-01 Residual Heat Renoval Pung Minimum Flow Bypass Differential Pressure Switch Found l Out of Tolerance Due to Setpoint Drift L 373/89-003-00 Setpoint Drift of Reactor Vessel Low hter Level Switch I
L 373/89-005-01 Main Steam High Flow Switch Outef-Tolerance Due to Setpoint Drift '
l 373/89-008-01 Setpoint Drift of Reactor Vessel Low Wter Level (Level 2) Switch 374/89-004-01 2A Residual Heat Removal Minimum Flow Bypass Switch Found Greater than Reject Limit During Surveillance Testing 374/89-006-01 Setpoint Drift of Low Level Cor. firmed Automatic Depressurization System Pennissive Switch L
G. COMPONENT "AILURE DATA i
Manufacturer Nomenclature Model Number MFG Part Nueer 50R Inc. Differential 103-AS-8212-WX-C I A- NA
! Pressure Switch JJTTX6 l: .
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> p.y , Form Rev 2.0 =j J LlWE IM REPORT (t1R)' TEXT COWilNUATION 'l DOCKET NUSER (2)' LER NilSER (6) Pee (3)
FACILITY NAME (1)
Year. ' fjj/
// Sequential /gj . Revision .i
'D f '
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' Alle County Stat ion Uni t 1. . . ' O' l 5 1 0 1 0 1 0 1 31 71 3 819 - 0lIl0 - 0 11 1 01 5 0F 01 5 ll 1 EXT . Energy industry identification System (Ells) codes are identified in the text as [XX). '
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Inches Of Indicated ;
Reactor Water Level-i "As Found" Setpoint-(Atmospheric Pressure)- + 24.60" 23.50" g - - -
5 23.36" ,
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> 20.11" Desired .i Reject . Setpoint F-Action Tolerance 19.40" Setpoint .j Limits = Limits e
. Atmos. Press .q l . . . .
> 18.69" .
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L. ; 15.44" 15.30" 1 q
.i Calculated Trippoint (Rated Pressure) ; 13.39" Technical Specification Nominal Setpoint. +- 12.50" l Technical-Specification Limit > 11.00" )
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[ Figure 1: Static 0-Ring Setpoint Information :l 1
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